Salvage syntheses and their relationship to nucleic acid metabolism. The intraerythrocytic stages of plasmodia are capable of synthesizing purine nucleotides and apparently deoxycytidylate by salvage syntheses. Data obtained by studying the incorporation of radioactive precursor molecules into intact cells and kinetic experiments on purified enzyme preparations suggest biosynthetic routes which, generally, are similar to those of the host's cell metabolism. However, details on the regulation of both the uptake of nucleosides and bases into the intraerythrocytic stages of plasmodia and of the metabolic routes involved in this incorporation are still lacking.


A quantitative long-term cryobiological study of malarial parasites. A study spanning 10 years indicates that the erythrocytic stages of malarial parasites can be stored indefinitely in the vapour phase of liquid nitrogen without significant loss of infectivity. The results also suggest that loss due to the recovery procedures exceeds any loss that may have occurred during freezing and thawing. When feasible, large pools of material should be divided into smaller aliquots before storing the organisms at a low temperature, since freezing a second time produces significant losses of infectivity. Sporozoites and exoerythrocytic stages may be treated similarly, but the optimum conditions for freezing these forms have yet to be determined.


Purification of intracellular forms of Plasmodium chabaudi and their interactions with the erythrocyte membrane and with serum albumin. A procedure using bovine serum albumin gradients was developed for the separation of P. chabaudi-infected mouse erythrocytes from uninfected cells. This procedure can be used for the purification of erythrocytes containing different developmental stages of the parasite. The purified parasites were able to synthesize in vitro all the proteins that they are capable of synthesizing in vivo. The intracellular forms of P. chabaudi were found to be associated with erythrocyte membrane components and this associated membrane was shown to lack glycophorin. The free parasites bound albumin from serum; this binding, which showed some specificity with respect to the origin of the albumin, might play a role in the stabilization or protection of the extracellular parasites.


Biochemical markers for strain differentiation in malarial parasites. Genetic differences between micro-organisms can be identified by studying variations in enzyme forms and DNA characteristics. Enzyme electrophoresis has revealed considerable genetic diversity in populations of malarial parasites and has enabled populations reproductively isolated from one another to be identified. Studies on rodent malarial parasites from four regions of Africa have shown that each species and subspecies can be distinguished by its pattern of enzyme forms. In subspecies in which enzyme polymorphism occurs, the frequencies of each combination of enzyme forms suggest an extensive degree of random mating in the population. Populations of Plasmodium falciparum are also enzymically polymorphic, similar enzyme variants being found in isolates from several parts of the world.


Interactions of rodent malarial parasites with Friend erythroleukemia cells in vitro. The ability of Plasmodium chabaudi and P. yoelii to bind to Friend erythroleukemia cells in vitro was examined. Extensive binding of P. yoelii and weaker binding of P. chabaudi was observed. Binding to mouse fibroblasts was not seen, although there was some binding to cells of a mouse mastocytoma. The binding of P. yoelii to Friend cells was sensitive to specific antiserum. The development of P. berghei and P. yoelii in Friend cells was followed by microscopic examination and measurement of the infectivity of those cells in mice. Friend cells infected with both species appeared to develop morphologically normal intracellular forms of the parasites. P. yoelii-infected cells were infective in sensitive mice for 3 days after addition of the parasites, and this infectivity was not sensitive to treatment in vitro with mouse anti-P. yoelii serum.


Should cultivated exoerythrocytic parasites be considered as a source of antigen for a malaria vaccine? Routine procedures for growing exoerythrocytic stages of avian malaria parasites in continuous culture have been available for many years. This system, adapted for the cultivation of mammalian forms, would have certain advantages in vaccine production, the great advantage being the potential for self-replication by both the host cell and the parasite. Many obstacles must be overcome, however, before efforts in this direction can be successful. The recent demonstration that merozoites of the exoerythrocytic cycle are immunogenic supports the view that efforts should be made to develop a mammalian culture system based on the exoerythrocytic stage.


Cultivation of bloodstream Trypanosoma brucei. Animal-infective forms of Trypanosoma brucei (Strain 427) were successfully propagated in HEPES-buffered RPMI 1640 medium in the presence of bovine fibroblast-like cells for over 310 days. The organisms grown in this system were morphologically identical to the long slender bloodstream forms, retained their infectivity for mammalian hosts, and displayed variant-antigen on their surface. Technical details for establishing such bloodstream form cultures are described in the present paper.


Preliminary studies on the histochemical differentiation of strains of Onchocerca volvulus microfilariae in Togo. Skin snips were taken from 75 people living in four villages of northern Togo. The 7824 microfilariae that emerged were examined by staining for the presence of acid phosphatase. Four distinct patterns of enzyme staining were observed, and descriptions of the stained microfilariae are given. The study confirms the view that a number of biological strains or variants of Onchocerca volvulus coexist in West Africa, and suggestions are made for further research that could result in the practical application of these observations in onchocerciasis control programmes.


Effect of Helisoma duryi on the survival, growth, and cercarial production of Schistosoma mansoni-infected Biomphalaria glabrata. Biological control of the intermediate hosts of S. mansoni and S. haematobium by means of a competitor snail,Helisoma duryi, has been suggested. In the present laboratory study, information was obtained concerning the interspecific competition between H. duryi and B. glabrata. The results indicated that the growth rate, mortality rate, and cercarial production of S. mansoni-infected B. glabrata were highly influenced by H. duryi. These observations agree with results obtained in earlier experiments concerning the interspecific competition between H. duryi and S. mansoni-infected B. pfeifferi. The exact characteristics of the influencing factor have not yet been determined, but the observations indicated that H. duryi could possibly be used as a biological control agent.


A programme of multiple-antigen childhood immunization in Yaoundé, Cameroon: first-year evaluation, 1975-1976. The Yaoundé multiple-antigen childhood immunization programme began in November 1975, making it one of the first expanded programmes on immunization operational in Africa. During the first 9 months, more than 22 000 children were immunized against poliomyelitis, measles, tuberculosis, smallpox, whooping cough, tetanus, and diphtheria. Evaluation of the programme showed the following rates of immunization coverage in the target population; 30% for DPT (one dose or more), 27% for poliomyelitis (one dose or more), 27% for BCG, 33% for measles, and 20% for smallpox. Eighty per cent of children received the correct vaccines for their age and vaccination status. Seroconversion to measles vaccine was 89% in those over 12 months of age but only 50% in those between 6 and 11 months of age. The major factor in low immunization coverage was felt to be inadequate publicity. The cost of the programme was estimated to be US $10 920. The cost of immunizing a child completely was estimated at US $1.90. Some logistic problems encountered during this initial year of operation are discussed.


Differential diagnosis of cerebellopontine angle tumours with special reference to the galvanic test. In the present paper an attempt to evaluate the diagnostic importance and reliability of the various vestibular tests was made. Special attention was paid to the galvanic test and its typical patterns of retrolabyrinthine lesions. The galvanic test is an important diagnostic method allowing a differentiation between a lesion of the vestibular endorgan and its peripheral neuron at an early stage. 40 surgically confirmed cases (24 acoustic neuromas and 16 cerebellopontine angle tumours) were analysed. In 36 cases the neurootologic diagnosis was correct while 4 cases of acoustic neuroma were not recognized as such. The diagnostic failure and some common pitfalls in the neuro-otological diagnosis of CPAT are discussed.


Pre- and post-operative brainstem responses in a case of acoustic neuroma, sparing the VIII nerve. A case is reported of a patient with an acoustic neuroma presenting with a 2 month history of tinnitus and a 25dB hearing loss with evidence of recruitment. The neuroma was removed via a posterior fossa approach with preservation of hearing. Preoperative and postoperative brainstem electric response (BSER) studies are compared. The preoperative results demonstrated a marked reduction in amplitude and increase in latency on the affected side which returned to normal after removal of the neuroma.


Neuraminidase- and trypsin-induced exposure to membrane receptors for IgG and IgM molecules on human peripheral blood lymphocytes. Brief incubation of human peripheral blood lymphocytes with vibrio cholerae neuraminidase (VCN) or trypsin revealed hidden membrane receptors for IgG and IgM molecules. The hidden receptors were found on T lymphocytes as shown by double-label and mixed rosetting experiments and by studies of T-enriched populations. Although IgM receptors were undetectable on freshly isolated lymphocytes, a mean of 17.1% of VCN-treated lymphocytes rosetted with ox erythrocytes coated with IgM antibody (EA-IgM). Prior to trypsin treatment a mean of 14.6% of human T lymphocytes rosetted with ox red cells coated with IgG antibody (EA-IgG). After incubation with trypsin this figure increased significantly (P less than 0.005) to 44.5%. VCN-treatment also significantly increased (P less than 0.005) the mean percentage of EA-IgG rosette-forming T cells to 38.5%. The T-cell receptor for IgG was shown to be trypsin-resistant while the IgM receptor was shown to be trypsin-sensitive. Using mixed rosettes, a tentative T-cell subset was identified which expressed both IgG and IgM membrane receptors. Also, a minor subset with IgM receptors alone and a larger subset with only IgG receptors were identified.


Increase in autologous erythrocyte binding by T cells with ageing in man. Studies made of 115 normal subjects of both sexes aged 20--94 years showed that autologous rosette-forming cell levels in human peripheral blood lymphocytes were related to age and sex. However, no such relationship was found in response to phytohaemagglutinin performed in the same subjects. The nature of these autorosettes in human peripheral blood lymphocytes was studied. A significant decrease in autorosette levels was observed after passage through nylon wool at high RBC/WC ratios, and at any ratio after E-rosette depletion. The results suggesting a T-cell origin of autorosettes were confirmed by the existence of mixed autologous erythrocyte and sheep red blood cell rosettes.


Prevention of autoimmune thyroiditis in T cell-depleted rats by injections of crude thyroid extract. The effect of intraperitoneal injections of crude allogeneic thyroid extract on the development of autoimmune thyroiditis in PVG/c rats subjected to thymectomy and repeated sublethal irradiation has been examined. Treatment with rat thyroid extract during the course of irradiation and before the onset of thyroiditis prevented the expected development of thyroid lesions and autoantibodies to thyroglobulin in these animals. Rats treated with crude rat liver extract under the same conditions developed thyroid disease similar to that of untreated controls. Treatment of thymectomized and irradiated rats with thyroid extract after the completion of the irradiation schedule failed to reduce the incidence and severity of thyroiditis in these animals as compared to that of untreated controls. The possible significance of these findings in relation to the pathogenesis of autoimmune thyroiditis in T cell-depleted rats is discussed.


In vitro cell response of Treponema pallidum-infected rabbits. III. Impairment in production of lymphocyte mitogenic factor. Production of mitogenic factor was examined in rabbits infected intratesticularly with T. pallidum and in control animals injected with saline or saline extract of normal rabbits' testes. Lymph nodes and spleen from animals killed 2, 6 and 12 weeks after injection were used as the source of lymphocytes, cultured in serum-free medium in the presence of Reiter antigen. The active supernatants of lymph node cells (LNAS) and spleen cells (SPAS) were examined for the presence of mitogenic factor using normal rabbit peripheral lymphocytes. The LNAS of control animals showed a mitogenic index (MI) between 4 and 6 and the infected animals less than 2. The SPAS of infected and control rabbits showed an MI of less than 2. The lower mitogenicity in LNAS of infected and that of SPAS of infected and control animals seems to be due to the presence of inhibitors of DNA synthesis.


Neurosurgical treatment of the dyskinesias. I have attempted to review what I consider to be the principal conclusions of a 25 year study of the neurosurgical treatment of the dyskinesias. The concept that the pathological disinhibition which is responsible for the production of these syndromes can be modified by destructive lesions within the thalamus or by prosthetic mobilization of inhibitory mechanisms of the cerebellum is supported by the results presented in this report. Neurosurgical treatment of the dyskinesias is potentially a relatively safe and efficacious means of alleviating incapacitation of a large group of patients. However, meticulous attention to patient selection as well as adherence to the general principles of surgical technique which have been reviewed are essential if the full potential of these approaches is to be realized.


The effects of serotonin precursors on the pressor response to intravenous clonidine in conscious rats. 1. The interaction of the biosynthetic precursors of serotonin with the alpha-adrenoceptor-mediated pressor response to intravenous clonidine was investigated in unanaesthetized rats. 2. Pretreatment with 100 mg/kg of either L-tryptophan or 5-hydroxytryptophan (5-HTP) reduced the magnitude of the pressor response elicited by intravenous clonidine (25 microgram/kg) to 15% and 11%, respectively, of that observed in control rats. 3. The depression by L-tryptophan of the clonidine-induced pressor response could be prevented by pretreatment with either the L-aromatic amino acid decarboxylase inhibitor Rö44602 or the serotonin antagonist methysergide.


The effects of low voltage current on healing of thermal third degree wounds. Bilateral third degree burns were created on the flanks of eight miniature swine. Each animal had one side treated daily with low intensity direct (LIDC) of 400 microamperes (muA) by contact electrode for 2 hours morning and afternoon until healing occurred. The polarity of the electrode was negative in 4 pigs and positive in 4 pigs. One group of 4 pigs had the eschar surgically removed 24 hours post burn. Weekly biopsies and cultures were taken of treated and control wounds. Results indicated: local treatment of 400 muA LIDC did not hasten or delay healing of thermal third degree burns; escharectomy hastened wound healing by 10 days, and superficial proteus infection occurred in 80% of all wounds.


The study of cerebrospinal fluid dynamics in apparently 'arrested' hydrocephalus in children. 18 children having hydrocephalus, which could be regarded clinically as 'arrested', underwent cerebral angiography and a constant infusion manometric test. Intracranial pressure was directly recorded in 3 cases. The above examinations indicated that hydrocephalus was still 'active' in 8 children. This was confirmed by the good results of the surgical treatment.


[Chemotherapy of osteosarcoma (author's transl)]. The cyclic chemotherapy scheme OS I/75 was tried in 6 patients with newly diagnosed osteosarcoma and in 3 patients with secondary metastases. The treatment consists of high dose methotrexate, followed by citrovorum-factor rescue, doxorubicine (Adriblastin) and cyclophosphamide (Endoxan). All 6 primary patients are in a continuous remission of 6+ to 21+ months (median 12+ months). The length of remission in the patients with metastases is 5.5+ and 8+ months. The haematological side effects led to an average prolongation of the cycle by 11 days in a planned cycle duration of 42 days. However, they were readily manageable. Among the other side effects two cases of Adriblastin myocardiopathy are remarkable which became apparent after methotrexate and ifosfamide. In order to improve possibilities for treatment regional centralisation of patient care and interdisciplinary and supraregional cooperation of treatment centres are necessary. A prospective treatment programme has been developed for the Federal Republic of Germany and Austria.


[T-cell leukaemia in adults: report of two cases (author's transl)]. Two cases of T-cell chronic lymphoid leukaemia in adults were classified by recently developed immunological methods. Clinically there was splenomegaly, hepatomegaly, marked anaemia, para-aortic lymph nodes, cutaneous infiltration, little peripheral lymph-node enlargement and significant marrow infiltration. Immunological tests of membrane antigens revealed T-cell determinants. T-CLL may differ in its course and prognosis from B-CLL and may require different treatment.


Nuclear RNA content and synthesis in anterior pituitary in intact, castrated and androgen sterilized rats. The content and uridine incorporation into nuclear RNA of anterior pituitary gland was studied in vitro in intact, castrated and neonatally testosterone treated rats of both sexes. In female rats a higher RNA content and a lower uridine incorporation rate could be observed than in males. The castration resulted in a marked increase of RNA content and uridine incorporation in male rats. Ovariectomy was followed by a decrease of RNA content which was accompanied by an increase of incorporation rate. Estradiol administration produced a biphasic change of RNA content and uridine incorporation in ovariectomized rats. From these findings a repressive action of estrogens on the nuclear RNA synthesis may be suggested. Neonatal testosterone treatment resulted in alterations of RNA synthesis which could be observed in both sexes.


Activity of delta5,3beta-hydroxysteroid dehydrogenase in cultured interstitial cells of mouse testes. Leydig cells isolated from mouse testes were cultured as monolayers for 18 days. Activity of delta5,3beta-hydroxysteroid dehydrogenase (delta5,3beta-OH-SDH) was demonstrated either in cells in suspension prior to the culture or in cultured cells. The dynamics of the enzyme activity in cultured cells was investigated for 11 days. Approximately 50% of cells in suspension prior to culture showed the activity of delta5,3beta-OH-SDH, while a majority of cells in culture contained active enzyme in the cytoplasm.


Effect of estradiol and progesterone on udder growth in goats in vivo and lipid synthesis in goat mammary tissue in vitro. The effect of estradiol-17beta (E) and progesterone (P) and E, P and deprenon (D; an inhibitor of prolactin secretion) treatment on udder growth, colostrum-like formation and on the induction of lipid synthesis in mammary organ culture were studied. Administration of E and P for 8-14 days induced udder growth and colostrum formation. Intensive mammary growth and udder distention with secretion occurred following hormone treatment. Simultaneous administration of D prevented both udder growth and colostrum formation. In mammary explants from E, P and D treated goats the rate of incorporation 14C-acetate into lipids was increased by insulin (I), cortisol (F) and prolactin (M) as compared with the effect of I or I plus F. The tissue from placebo treated goats and goats treated with E and P responded to M either slightly or not at all. The high sensitivity of mammary tissue from goats treated with E, P and D to M was demonstrated immediately following the administration of E and P for 8 days and also 10 days after the treatment, but not 23 days following hormone administration.


In vitro conversion of [4-14C]-androstenedione and [4-14C]-testosterone by ovarian tissue of pregnant rabbits. The follicles, corpora lutea and interstitial tissue from 15 and 28 days pregnant rabbits were incubated with radioactive androstenedione and testosterone. Both precursors were aromatized to estradiol-17beta and estrone by ovarian follicles from 15 and 28 days pregnant rabbits but not by the corpora lutea and interstitial tissue. Testosterone appeared to be the better precursor for estrogens synthesis. Interconversion of androstenedione and testosterone was observed in each ovarian compartment.


Aldosterone binding in bovine ciliary body. The presence of aldosterone binding which was not identical with dexamethasone binding was verified in the ciliary body of the bovine eye in vitro. The site of aldosterone binding was presumably located in the non-pigmented layer of ciliary epithelium. Specific aldosterone binding was found also in lens epithelium but not in corneal epithelium. The finding of receptor-like aldosterone binding confirms the concept of possible mineralocorticoid-dependent active sodium transport through the ciliary and lens epithelium in the eye.


Effect of insulin and glucose on the activity of insulin-degrading enzymes in rat liver. The degradation of insulin by insulin protease and glutathion-insulin transhydrogenase (glutathioneproteindisulphide oxidoreductase--EC 1.8.4.2, GIT) was measured in rat liver either after replacing food and water by 15% glucose solution, or after daily insulin administration 8 U daily for 3 days or after fasting. The breakdown of radioiodinated insulin was followed by measuring the increase of TCA soluble radioactivity during incubation of cell fractions with 125I insulin at 37 degrees C. The highest GIT activity was observed in liver microsomes of rats after glucose feeding and after insulin administration, whereas enzyme activity of fasted animals did not essentially differ from corresponding values of normally fed controls. The insulin protease in cytosol of liver cells remained unchanged after these procedures. The important role of GIT in insulin degradation seems to be conclusively demonstrated.


Danazol inhibits steroidogenesis in the rat testis in vitro. The effects of danazol on steroidogenesis in vitro in the rat testis were examined by studying: 1) androgen synthesis in rat Leydig cells cultured with danazol, 2) danazol binding to rat testis microsomal cytochrome P-450, and 3) enzyme kinetics of danazol inhibition of the microsomal enzymes of testicular steroidogenesis. Concentrations of danazol as low as 1 micrometer suppressed LH-stimulated testosterone and androstenedione production in cultured Leydig cells. The addition of danazol to a preparation of testicular microsomes elicited a type I cytochrome P-450 binding spectrum, with an apparent spectral dissociation constant (Ks) of 4.8 micrometer. Danazol inhibited progesterone and 17alpha-hydroxy-progesterone binding to microsomal P-450 with apparent spectral inhibition constants of 2.4 micrometer and 2.8 micrometer, respectively. Danazol competitively inhibited 3beta-hydroxy-delta5-steroid dehydrogenase-isomerase (apparent enzymatic inhibition constant, KI = 5.8 micrometer), 17alpha-hydroxylase (KI = 2.4 micrometer), 17,20 lyase (KI = 1.9 micrometer), and 17beta-hydroxysteroid dehydrogenase (KI = 4.4 micrometer). These findings indicate that low concentrations of danazol directly inhibit steroidogenesis in the rat testis in vitro.


Elevation of serum 25-hydroxycalciferol levels in androgen-treated and ultraviolet-irradiated rats. Administration of 4-8 mg testosterone propionate significantly raised 25-hydroxycalciferol levels in the ultraviolet irradiated rats compared to the ultraviolet irradiated controls, but failed to influence serum 25-hydroxycalciferol levels in the non-irradiated animals. Estradiol benzoate and progesterone did not influence serum 25-hydroxycalciferol levels regardless of the ultraviolet irradiation. These findings implicate that testosterone enhances vitamin D biosynthesis induced by ultraviolet irradiation in rats, in accordance with the clinical observation that males often show higher levels of serum 25-hydroxycalciferol than females.


Lennox-Gastaut syndrome and computerized axial tomography findings. Computerized axial tomography (CAT) in 38 patients with Lennox-Gastaut syndrome showed normal findings in 20 patients and abnormalities in 18; diffuse cerebral atrophy (8) was the most common abnormality. These findings are not basically different from those recently reported by Gastaut and Gastaut (1976). Emphasis is laid upon age and possible increase of diffuse abnormalities with advancing age. The observation of 2 cases with cerebellar atrophy is also discussed.


Enhancing effect of low dose cyclophosphamide treatment on the in vitro antibody response. We have studied the effect of cyclophosphamide (CY) administration on the subsequent in vitro antibody response in the mouse. Treatment with a low dose (20 mg/kg) of CY four days before culture results in an increased IgM response to the T-independent antigen trinitrophenylated polyacrylamide (TNP-PAA), without affecting the background response of unstimulated cultures. This suggests that CY treatment eliminates a short-lived suppressor cell, involved in the regulation of the in vitro B cell response. In contrast, the same regimen decreases the ability of nude mouse spleen cells to respond to TNP-PAA, showing that the target of CY-enhancing effect is a mature T cell. The increased response observed in conventional mice should be the result of a balance between the direct suppressive effect of CY on B cells and the elimination of a suppresor T cell, the latter phenomenon being of predominant significance in our conditions. The target of CY-enhancing effect is nonadherent to plastic, but adherent to Sephadex G-10 columns.


Structure of mouse Fc receptor.

Structure of mouse Fc receptor. A variety of mouse cell types were externally labeled with radioactive iodine and solubilized in detergent. A single chain radioactive molecule of mol. wt. 120 000 was precipitated from lysates of surface-labeled lymphocytes, macrophages and fibroblasts by complexes between pneumococcal type 3 polysaccharide and its homologous rabbit antibody in the IgG form, but not as F(ab')2 or Facb. The same results were obtained using an alternative precipitating system, namely ovalbumin and IgG and F(ab')2 forms of rabbit anti-ovalbumin. The 120 000 mol. wt. compound could not be detected on a thymoma cell line (5178) previously known to lack the Fc receptor. On the basis of these criteria the material was therefore identified as mouse Fc receptor. Although very susceptible to proteolysis, the fragments resulting from digestion remain associated by disulfide bonds in such a way as to still bind to the antibody-antigen precipitate. The proteolytic fragmentation products (mol. wts. 75 000, 45 000, 20 000 and 10 000) only become apparent upon chemical reduction, but the ease with which the molecule is degraded explains the wide variation in mol. wts. reported for the Fc receptor, and is perhaps a clue to explain the biological role of the molecule.


Imbalances in T cell subpopulations associated with immunodeficiency and autoimmune syndromes. Abnormal proportions of the distinct T cell subpopulations binding the Fc portion of IgM (T-M) cells and those bearing receptors for the Fc portion of IgG (T-G) cells, were observed in blood samples from patients who had congenital or acquired abnormalities of the thymus, severe combined immunodeficiency, or an unexplained primary deficiency in cell-mediated immunity; most had too few circulating T-M cells and often an overabundance of T-G cells. In an in vitro evaluation of lymphocyte from one of three thymoma patients with an elevated T-G subpopulation, removal of T-G cells abrogated the suppression of T-M cell help of B cell differentiation induced by pokeweed mitogen. A spectrum of patients with sex-linked infantile agammaglobulinemia, variable hypogammaglobulinemia, and selective IgA deficiency, and a few patients with autoimmune syndromes infrequently had distorted representation of these T cell subpopulations in the circulation. This suggests that B cell dysfunction in many of these patients is not merely due to numerical excesses or insufficiencies of helper or suppressor T cells.


Regulation of delayed-type hypersensitivity. I. T suppressor cells for delayed-type hypersensitivity to sheep erythrocytes in mice. Mice injected with 1 X 10(8) sheep red blood cells (SRBC) into the footpad showed high levels of delayed-type hypersensitivity (DTH) to SRBC 4-8 days after the injection. In contrast, mice injected intravenously with 1 X 10(9) SRBC were unresponsive to DTH induction through 1 X 10(8) SRBC injected into the footpad. This suppression of DTH was maintained for at least 6 weeks and was transferable spleen, lymph node and thymus cells to normal syngeneic recipients. Bone marrow cells, on the other hand, did not contain the suppressor cells. The suppression of DTH was antigen-specific in that DTH to chicken red blood cells and contact sensitivity to 2,4-dinitrofluorobenzene was not affected. The suppressor cells were theta-positive and Ig-negative. They appeared in the spleen in optimum number 3-4 days after induction. The suppressor cells affected both the induction and manifestation of DTH. The presence of suppressor and effector cells for DTH inducible by different routes of antigenic presentation reflects the dynamic balance in the regulation of DTH.


B cell antigens on effectors for natural cell-mediated cytotoxicity. Cell suspensions enriched for N cells, the effector cell for human natural cell-mediated cytotoxicity, were observed to react strongly with a rabbit antiserum directed against an antigen associated with B cells. Treatment of the effector suspension with the antiserum resulted in inhibition of natural cell-mediated cytotoxicity. The blocking occurred, however, only with the intact antibody indicating that inhibition was caused through the formation of antigen-antibody complexes. The antiserum was then employed to arm natural effector cells to react specifically with B cell lines. Specific arming was achieved after the formation of antigen-antibody complexes was prevented by initially reacting the effector suspension with F(ab')2 of the anti-B cell antibody. This study also supports the identity of the subset of cells responsible for antibody-dependent and natural cell-mediated cytotoxicity and the similarity in their mechanisms.


Organ culture studies of nude mouse thymus. There is evidence that peripheral lymphoid organs of nude mice, born from homozygous matings, contain a small proportion of theta-positive lymphocytes indicating that nude mice may not be totally devoid of T cell function. It has been suggested that such lymphocytes may develop within the dysplastic nude thymus itself. While this suggestion receives no support from morphological studies, it has been claimed that on explanation to organ culture the developing nude thymus becomes lymphoid. In this present study we confirm the presence of theta-positive lymphocytes in peripheral lymphoid tissues of homozygous nude mice born of nude parents. However, when we have organ-cultured nude thymus, explained from homozygous nude embryos at days 13, 14, 16 and 18 of gestation, we have found no histological sign of lymphopoiesis nor have we detected any theta-positive cells in such cultured material. On the contrary, the nude thymus in vitro develops into the polycystic structure characteristic of the adult nude thymus. We conclude that the small number of theta-positive cells present in the periphery result from extrathymic differentiation.


T lymphocyte tissue culture lines produced by cell hybridization. This study describes the generation of permanent T cell tissue culture lines by cell fusion techniques. The AKR strain-derived T cell tumor BW 5147 was hybridized in the presence of polyethylene glycol with various T cell populations isolated from antigen-sensitized mice. Surface analysis of resulting hybrid cell lines showed expression of both Thy-1.2 and H-2 antigens which are characteristic for the lymphocyte used for fusion. In contrast, in hybrids derived from spleen cells neither expression of Ig nor of B cell-typicyl Ia determinants was found suggesting either preferential hybridization of BW 5147 cells with T lymphocytes or extinction of B cell markers in hybrid cells. These hybrid lines which may display the immunological properties of the T cell population chosen are presently investigated for their antigen reactivity.


Natural cytotoxicity in man: activity of lymph node and tumor-infiltrating lymphocytes. Lymphocytes from blood, lymph node and tumor have been tested for cytotoxicity against the K562 cell line which is known to be highly sensitive to lysis by spontaneously reactive cells. Cytotoxicity was found in all 13 samples from healthy donors and in 17/32 cancer patients. By contrast, activity was determined in only 1/18 lymph node and 1/14 preparations of tumor-infiltrating lymphocytes. Lymph node cells were similarly nonreactive against 3 other cell lines known to be sensitive to natural cytotoxicity. Studies of the composition of the effector populations revealed no absolute deficit of a particular cell type although there were differences between them resulting from the different isolation procedures used. Enrichment of the lymph node population for non-T, non-B lymphocyte was ineffective in inducing cytotoxicity in previously nonreactive samples although this procedure uniformly increased the cytotoxic potential of blood lymphocytes. Tests with blood taken during operation showed that the lack of reactivity in these preparations was unlikely to be a result of the effects of anesthesia or surgery. The reason for the low cytotoxicity in the lymph node and tumor-infiltrating lymphocytes is as yet undefined.


Suppressor T cells in low zone tolerance. II. Characterization of suppressor T and amplifier cells by physical and serological methods. Suppressor cells involved in low zone tolerance to bacteriophage fd have been characterized by serological and physical methods. Suppressor T cells are peripheral T2 cells which are Ly-1-, Ly-2+ and Ia+. They are of high electrophoretic mobility, sediment 5 mm/h at 1 x g in a linear Ficoll 70 gradient, but are not restricted to a distinct band in a discontinuous bovine serum albumin gradient. Adherent phagocytic cells of low electrophoretic mobility can act as amplifier cells with a much shorter half-life than suppressor T cells.


Growth regulation of a murine lymphoma cell line by a 2-mercaptoethanol or macrophage-activated serum factor. A mouse lymphoma cell line has been established that is dependent for growth on the presence of an activated serum component. This growth factor is found in an inactive form in fetal bovine serum (FBS) and can be activated by 2-mercaptoethanol and by macrophages. A factor-containing fraction can be separated from FBS by Sephadex G-100 chromatography and once activated, can be used as a substitute for whole serum in the culture medium without adverse effect on the cell growth. The significance of these findings with respect to the study of the immune response and cancer research is discussed.


Thymocyte subpopulations in young and adult mice. I. Separation by density gradient and steroid treatment. Thymocyte subpopulations obtained after centrifugation on Ficoll density gradients have been studied in young and 6-week-old mice. Whereas the totality of the thymocytes appeared theta-positive, gradient fractionation showed the existence of a subpopulation of immunoglobulin and theta-negative lymphocytes among the lightest cells. Similar separation was obtained in both age groups in terms of the distribution of such theta-negative cells as well as of phytomitogen responses. However, cell pools with characteristics of cortical cells were less well represented in 2 to 10-day-old mice than in adult mice, indicating that post-natal thymic development is essentially associated with the appearance of cortical cells. The gradient did not however, provide a clear separation assessed on other parameters such as theta antigen, concanavalin A and phytohemagglutinin responses and steroid sensitivity. Cellular heterogeneity for a given cell density is discussed in relation to the hypothesis of two separate maturation pathways of thymocytes.


Thymocyte subpopulations in young and adult mice. II. Study of steroid-resistant populations by means of a specific heteroantiserum. Mouse steroid-resistant (Sr) cells of the thymus have been studied by means of a specific heteroantiserum. This antiserum was obtained in the rabbit after immunization with Sr thymocytes followed by absorption with high density cells isolated on a Ficoll density gradient shown to include a majority of steroid-sensitive (Ss) cells. Antigens defined by this antiserum were found on Sr thymocytes and on a significant portion of spleen and lymph node cells, but not on Ss cortical thymocytes. Cells sensitive to this antiserum appear early in the thymus (by day 15 of gestation) at the same time as Ss cells. These results suggest (a) the existence of an autonomous Sr cell line, with its own antigenic markers appearing early in ontogeny (at the same time as Ss cells), and showing wide heterogeneity in density, possibly linked to variable degrees in maturation, and (b) the medullary origin or some peripheral lymphocytes in lymph node and spleen cells that share antigenic markers with Sr thymocytes.


Serum half-life and organ distribution of radiolabeled colony stimulating factor in mice. Granulocyte-macrophage colony stimulating factor (GM-CSF) from mouse lung conditioned medium has recently been purified. This GM-CSF was radioiodinated using the chloramine T method, but dimethylsulfoxide was needed to prevent the loss of biological activity during the iodination. 125I-labeled GM-CSF was isolated from the reaction mixture by gel filtration and affinity chromatography with concanavalin A-Sepharose. One hour after intravenous injection of 125I-labeled GM-CSF almost 80% of the radioactivity was still localized in the serum. 125I-labeled GM-CSF was cleared from the blood of C57BL mice with a serum half-life of 7.3 +/- 1.3 hours. Six hours after intravenous injection 125I-GM-CSF appeared to be distributed throughout most of the tissues of C57BL mice. There was no selective concentration of 125I-labeled GM-CSF in the bone marrow, but levels in the kidney were three times higher than expected from the distribution of 125I-labeled mouse serum albumin. 125I detected in the blood 6 hours after injection of 125I-labeled GM-CSF was precipitable with trichloroacetic acid and bound to concanavalin A-Sepharose. 125I detected in the urine was not macromolecular and appeared to result from the degradation of 125I-labeled GM-CSF.


Analysis of populations of macrophage-granulocyte progenitor cells stimulated by activities in mouse lung-conditioned medium. Granulocyte and macrophage progenitor cells which clone in semi-solid agar cultures were characerized by separating murine bone marrow cells by equilibrium density centrifugation. These in vitro colony forming cells (CFU-c), when induced by stimuli in mouse lung-conditioned medium, were found to be heterogeneous in their density properties. Differences were found in the dose responsiveness of two major subpopulations of these progenitor cells. One population (modal density 1.074 gcm-3) responded in an identical manner to stimuli present in mouse lung-conditioned medium and pregnant mouse uterus extract. A second population (modal density 1.070 gcm-3) was found to be markedly different in its dose responsiveness to mouse lung-conditioned medium, from the other subset (1.074 gcm-3). The cloning of the low density progenitor cells and the observed dose responsiveness was found to correlate with an activity present in a stimulus in mouse lung-conditioned medium but was not identical to the stimulus in pregnant mouse uterus extract. No subpopulation, however, gave exclusively granulocyte or macrophage colonies.


Direction-specific optokinetic modulation of monosynaptic hind limb reflexes in cats. The excitability of hindlimb extensor and flexor motoneurons is tonically modulated by animal tilt and a large visual stimulus rotating about the animal's line of sight. This direction-specific modulation is opposite for extensor and flexor motoneurons and opposite for optokinetic and vestibular stimuli, thus combining to a functionally significant pattern of postural reflexes.


Biochemical variation in the Rana esculenta complex: a new hybrid form related to Rana perezi and Rana ridibunda. Investigations of the green frogs from western Europe for electrophoretic variations at 4 enzyme loci demonstrated a new form which must be considered as a hybrid between Rana ridibunda and R. perezi. Biochemical evidence supports the hypothesis that its reproduction is hybridogenetic, as it is for R. esculenta.


Histologic changes in mouse lymph nodes after treatment with antitheta-globulin. The DBA/2 mice were treated with 4 successive subcutaneous injections of rabbit anti-theta-gammaglobulin and the histology of the axillary lymph nodes was studied 1, 2, 4, 7, 14 and 21 days after the last dose. The histology of the lymph nodes was assessed according to the standardized reporting system of Cottier et al. (1973). The histologic findings were compared with those found in mice treated with anti-thymus-gammaglobulin, normal rabbit gammaglobulin and those in untreated DBA/2 mice. Anti-theta-gammaglobulin was found to be a potent suppressor of the small lymphocytes in the lymph node paracortical areas. At the same time, it elicited a strong humoral immune response in the nodes manifested as proliferation of large pyroninophilic cells and plasma cells in the medulla and germinal centers. The standardized reporting system of Cottier et al. was found to be extremely suitable for assessing the histology of the experimental animals' lymph nodes and its acceptance into general use is strongly advocated.


Chimeric drift in allophenic mice.

Chimeric drift in allophenic mice. The composition of the immune system of 33 allophenic mice of four different types [C57BL/6  in equilibrium DBA/1, C57BL/6 in equilibrium (CBA X CBA/H-T6), C57BL/6 in equilibrium (A X SJL), DBA/1 in equilibrium (CBA X CBA/H-T6)] was studied. It was found that the parental composition of the peripheral white blood cells changed significantly during a two-month interval in 11/33 or 33% of the mice studied. This phenomenon has been termed chimeric drift. The animals were sacrificed between 9 and 16 months of age, and the parental composition of the peripheral white blood cells, spleen white blood cells, and thymocytes was determined on the day of sacrifice. It was foound that the peripheral white blood cell and spleen white blood cell compositions showed a high degree of correlation. However 8/33 or 24% of the mice studied showed discordance of the spleen and thymocyte cell populations. Seven of the 8 mice which showed spleen-thymocyte discordance, had also shown evidence of chimeric drift earlier in their lives. We suggest that this is evidence that chimeric drift may have an immunological basis.


Study on the exocrine pancreatic function by the oral administration of N-benzoyl-L-tyrosyl-para-aminobenzoic acid. N-benzoyl-L-tyrosyl-p-aminobenzoic acid (Bz-ty-PABA) was orally administered to 11 controls, 10 patients with chronic pancreatitis, 7 patients with diabetes mellitus and 6 patients with liver cirrhosis. The cumulative 6 h recovery rate of PABA in the urine was significantly lower (P less than 0.005) in patients with chronic pancreatitis (49.1 + or - 10.1 percent), diabetes mellitus (50.4 + or - 20.4 percent) and liver cirrhosis (52.5 + or - 13.0 percent) than in the control group (79.5 + or - 12.0 percent) (mean + or -S.D.). This test is considered to be useful in the diagnosis of pancreatic exocrine insufficiency, especially in chronic pancreatitis. Patients with diabetes mellitus frequently has demonstrable abnormality of pancreatic exocrine function. Liver cirrhosis causing severe impairment of liver functions seemed to interfer with the elimination of PABA.


alpha1-Antitrypsin variants in different racial groups in Malaysia. In a study of Malaysians of different racial groups, 1,510 sera (908 from Malays, 371 from Chinese and 231 from Indians) were identified for their protease inhibitor (Pi) types. The gene frequencies for the alleles PiM, PiS and PiX in Malays were, respectively, 0.979, 0.015, and 0.007. In Chinese, the frequencies were 0.981, 0.019 and 0.000, and in Indians they were 0.976, 0.24, and 0.000. It is interesting that the usually rare PiX type is found in appreciable frequency in the Malays. Two different types with unusual behavior and obscure origin were also found.


Reactive and non-reactive lymphocytes in experimental allergic encephalomyelitis. Myelin basic protein (BP),induces an increased in vitro proliferative response of peritoneal exudate cells (PEC), compared with that given by pheripheral blood lymphocytes (PBL), in guinea-pigs with experimental allergic encephaloMYELITIS (EAE). This response is determined by the nature of the lymphocytes in such exudates. We have also found that: (a) the majority of peritoneal lymphocytes from non-sensitized animals are E-rosetting (T cells) (59 percent) or null cells (greater than 40 percent) with EAC-rosetting (B cells) comprising 1 percent or less of cells; (b) both T cells and null cells respond equally to BP as determined by a technique combining rosette-formation and autoradiography; (c) the increased in vitro peritoneal lymphocyte response in animals with EAE cannot be explained solely by the number of null cells since peripheral blood and lymph nodes also contain appreciable numbers of null cells.


Cellular basis of persistent tolerance induced by an aggregate free heterologous immunoglobulin. Attempts were made to break the tolerance of lymph node B cells to deaggregated human gamma globulin. Using allotype-congenic mice, lymph node cells from virgin or tolerant (5 mg) CBA/Igb donors were transferred tonormal CBA/Iga recipients and the proportion of responding donor B cells estimated 1 and 13 days later. The response of the non-tolerant virgin cells diminished with time but was still detectable at 13 days whereas the response of the tolerant cells was tenfold lower than normal cells at day 1 and was not detectable at 13 days. This functional deletion of tolerant cells was not reversed by enzymatic stripping of the immuno-globulin receptors before transfer, nor by removing T cells-which might have had a suppressor action. In other experiments Igb mice were thymectomized or left as controls at various times before tolerance induction. Lymph node cells from these mice were transferred, together with non-tolerant Iga cells, to irradiated recipients. The cell from tolerant thymectomized donors strongly suppressed the response of non-tolerant cells, whereas the tolerant control cells showed no suppressor activity. It is considered that B-cell tolerance can be maintained by something other than receptor blockade, or active suppression-although the latter can arise in some circumstances.


Receptors for IgM and IgM-antigen complexes on human T-lymphocytes reacting with specific anti-human-T-cell antiserum. A receptor on T lymphocytes that can bind IgM-type antibodies, without, as well as after prior complex formation between the antibody and Esh (sheep red blood cells) has been detected. No prior in vitro incubation of freshly drawn and isolated peripheral blood lymphocytes is required for the expression of the IgM antibody binding receptor on T cells. Results obtained in experiments designed for the simultaneous detection of lymphocytes reacting with specific rhodamine labelled antihuman-T cell antiserum and forming rosettes with EA-IgM complexes of Esh and the IgM antiserum fraction showed the receptor for IgM antibody to be present exclusively on T cells. Pre-incubation of T cells with free IgM or its Fc fragments leads to inhibition of rosette formation with EA-IgM. Treatment of the IgM type pentameric antibody with dithioerythritol to cleave pentameric IgM reduces the percentage of EA-IgM rosette forming cells (RFC) significantly. The possible biological significance of this receptor is discussed.


Differentiation of functionally active mouse T lymphocytes from functionally inactive bone marrow precursors II. Limited recovery of T-cell responses from mouse bone marrow in tissue culture. The limited differentiation of mature T cell function from mouse bone marrow in tissue culture is described and compared with similar differentiation occuring in vivo in irradiated bone marrow protected mice. Data are presented to show that a pool of precursors, similar in size to that able to produce early (transient?) regeneration in thymectomized recipients, is responsible for the development of mitogen responsive T cells active in MLC (proliferation) and CML (development of cytotoxic cells) assays. In contrast, a helper cell population which augments antibody formation from T-depleted normal spleen cells derives from a pool of similar precursors yet does not seem to be theta positive. Similarly, larger cells (perhaps typical of those giving rise to suppressor T cells in vivo) give rise to a suppressor cell pool after 4 days of culture, though again only a fraction of this suppressor activity could be attributed to theta positive cells. It is suggested that much of the data for regenration of T lymphocytes in vitro from T-depleted sources needs to be re-interpreted in terms of this evidence for a pool of post-thymic precursors of T cells in such T-deficient cell populations.


The influence of antigen presentation on the generation of T-helper cells with different functions. Thymocytes adoptively transferred into syngeneic irradiated recipients can be primed with antigen (KLH) to generate two types of helper function termed 'specific' and 'non-specific'. Low doses of KLH given without adjuvant generate high levels of non-specific compared to 'specific' helper T cells. Large doses of KLH given in adjuvant (FCA) generate high levels of both types of helper T cell. Explantations for this observation are discussed.


Selective accumulation of cells with 'B' properties in stimulated lymph nodes. Draining lymph nodes from mice which had been stimulated with bacterial adjuvants or the skin sensitizing agent, oxazolone, showed a marked increase in cell content, presumably due to lymphocyte immigration. A surprisingly large proportion of these cells exhibit properties of B lymphocytes: the presence of surface Ig, lack of Thy-1-like antigen and responsiveness to lopopolysaccharide (LPS). The relationship between the presence of surface markerand responses to class-specific mitogens, of cells from the stimulated nodes, was established by testing fractionated lymphocyte populations. Enriched T cells did not react to LPS, whereas removal of cells with Thy-1 antigen by specific antisera eliminated the reactions to T mitogens but had little or no effect on the LPS response. The data thus suggest that B cells, which make up a small portion of the circulating lymphocyte pool, are selectively accumulated in lymph nodes stimulated by different immunogens, including T-specific stimulants. This interpretation contradicts the generally accepted assumption, that stimulat lymph nodes trap mostly T lymphocytes.


Immunity to Trichinella spiralis. I. Transfer of resistance by two classes of lymphocytes. Rats can be solidly immunized against Trichinella spiralis by a series of methyridine-terminated oral infections with T. spiralis larvae. Injections of thoracic duct lymphocytes (TDL) obtained from such animals can protect normal rats against a Trichinella challenge. The protective cells belong to two populations which differ with respect to their adherence to affinity columns prepared with rabbit antibody to rat F(ab')2. Immune lymphocytes in the column-adherent B cell fraction are inhibited by vinblastine, whereas those in the non-adherent, T cell fraction are resistant to this drug. The above observations suggest that acquired resistance to T. spiralis is mediated by two classes of lymphocytes: B cells which are delivered to the thoracic duct and hence to the blood while still in active cycle, and T cells which have a potentially long life-span and presumably belong to a pool of recirculating small lymphocytes.


Immunity to Trichinella spiralis. II. Expression of immunity against adult worms. Thoracic duct lymphocytes or purified T or B cells obtained from specifically immunized (Lewis x DA)F1 hybrid rats can protect normal recipients against an oral challenge infection with T. spiralis. The immune cells increase the rate of expulsion of adult worms from the small intestine. Immune TDL do not affect adult worm fecundity, as they do in other strains of rats, or the penetration and development of newborn larvae in muscle cells. Irradiated F1 rats reconstituted with either immune TDL or class-enriched populations of immune T or immune B cells also expel adult Trichinella more rapidly than do unprotected controls. However, unfractionated TDL and inocula enriched in B cells are more efficient than T cells in promoting worm expulsion. The above finding, taken in conjunction with the tissue disposition of labelled lymphocytes in the tissues of recipient rats, implies that immune T cells have a 'helper' function in promoting the formation of protective B cells.


Macrophage-induced thymic lymphocyte maturation. Guinea-pig peritoneal macrophages were found to influence the functional maturation of thymic lymphocytes. Autologous thymic lymphocytes obtained from macrophage co-cultures responded to three different mitogens and were reduced in their ability to reassociate spontaneously with macrophages. Neither of these properties were found in thymic lymphocytes that had not been cultured with macrophages. These functional changes appeared to be specific for macrophages since thymic lymphocytes incubated with skin fibroblasts failed to respond to the test mitogens. Furthermore, they were not the result of either the inactivation, by macrophages, of a putative suppressor thymocyte or a soluble macrophage product. In addition to influencing the functional maturation of thymic lymphocytes, macrophages also appeared to play a direct role in inducing the mitogen response of functionally mature cells.


Differentiation of human peripheral blood B lymphocytes. Human B-lymphocyte differentiation was studied by measuring the capacity of such cells, isolated from peripheral blood, to synthesize and secrete Ig after pokeweed stimulation. Results show that a maximum incorporation of [3H]-thymidine took place 2 days before the appearance of detectable Ig-secreting cells. On the 7th day after pokeweed stimulation, when Ig synthesis and secretion are at a maximum, [3H]-thymidine uptake was low. Since inhibition of DNA synthesis 3 days after pokeweed stimulation completely prevents the generation of Ig-secreting plasma cells, initial DNA synthesis is apparently essential before Ig-secreting plasma cells can develop in response to pokeweed stimulation.


Direct cytotoxicity against chicken erythrocytes in mice. I. Fundamental nature of T cell-mediated cytotoxicity. Immune responses were examined after immunization with chicken erythrocytes (CRBC) in mice. Cytotoxicity of spleen cells was assessed by the release of 51Cr from labelled target cells. (1) At early stages (day 4-7) after primary intraperitoneal immunization, direct cytotoxicity of spleen cells was raised efficiently in C57BL/6 and AKR mice, but not in C3H/He, SL and DDD mice. Delayed hypersensitivity and antibody production were raised to almost the same extent in all the strains at such periods. (2) Effector cells in direct cytotoxicity were theta-positive and IgG-positive, and glass-nonadherent and Nylon wool column-adherent. Effector cells in antibody-dependent cell-mediated cytotoxicity in the presence of antibody to CRBC were eliminated by treatment with anti-IgG serum, but not by treatment with anti-theta serum. (3) Cytotoxicity and antibody production were raised efficiently after intraperitoneal or intravenous immunization, but not after footpad immunization. On the other hand, delayed hypersensitivity developed most efficiently after footpad immunization.


Evolution of three lymphocyte markers in newborn, preterm infants. Nine newborn, preterm infants have been studied at the ages of 1-3 days, 8-10 days and 22-24 days for surface markers on peripheral blood lymphocytes. As compared to adult controls, four of the infants had a low proportion of sheep RBC binding lymphocytes at birth, but at 1-3 weeks of age all infants had reached the adult level. Lymphocyte receptors for Fc of IgG and for complement, although both mainly characterizing non-T cells, evolved differently post partum: the proportion of Fc-receptor-bearing lymphocytes tended to increase with age of the infant, whereas already at birth complement receptor-bearing lymphocytes were at or above the adult level.


Surface characteristics of the human K (killer) lymphocyte. The human non-allergized K (killer) lymphocyte has been characterized using selective depletion and isolation procedures based on surface markers. It was found to be a non-thymus-dependent, Fc-receptor-bearing cell. In an area which is controversial, our findings also indicate that the cell has immunoglobulin on its surface but lacks the receptor for the C3 component of complement (mouse). This would suggest it to be an (Fc + C3-) B lymphocyte.


T lymphocytes bearing receptors for Fc of IgG in guinea pig peritoneal fluid. A model for human extrahaematic fluids. Surface markers of lymphocytes from peritoneal fluid of the guinea pig are studied and compared with those of lymphocytes from thymus, peripheral blood and spleen. The great majority of peritoneal lymphocytes form rosettes with rabbit red cells and bear receptors for Fc of IgG (T Fc+ cells). Lymphocytes with these characteristics are poorly represented in blood, thymus and spleen. Guinea pig peritoneal lymphocytes can be compared, as far as surface markers are concerned, with lymphocytes from human cerebrospinal fluid and transudates.


Differential effect of vinblastine and colchicine on human active and total T rosettes. The effect of vinblastine and colchicine on human blood T cell rosette formation with sheep erythrocytes was assessed. For some concentrations, both drugs increased the percentage of active T rosettes. In contrast, the total T rosette percentage was decreased by the same drugs. These experiments further confirm the heterogeneity of T cell rosettes and suggest the existence of three types of sheep red blood cell receptors on human blood T lymphocytes.


Influence of serum from atopic children on T lymphocytes. The relative and absolute number of peripheral T cells was found to be depressed in atopic children. Sera from atopic children had slightly less stimulatory effects on lymphocyte DNA synthesis induced by PHA, Con A and PPD, than sera from nonatopic children. This finding indicates an occurrence of inhibitory factor(s) in atopic serum. Sera from some severely ill atopic patients almost completely abolished mitogen-induced lymphocyte DNA synthesis. Inhibition by atopic serum appeared to be an early event in lymphocyte mitogenesis and not due to CRP, IgE or factors binding to mitogens. Lymphocytes from atopic children were no more sensitive to suppressive influences of atopic serum factors than were lymphocytes from adult blood donors. Normal serum enhanced mitogen-induced DNA synthesis more in lymphocytes from adult blood donors than in those from atopic children. The results indicate that, although the T cell defect in atopy may be partly caused by serum factors, occurring during clinical allergic disease, the main reason for the defect is probably an altered reactivity of the T lymphocytes in atopic individuals.


A solid-phase radioimmunoassay for IgG and IgM antigammaglobulin factor in rheumatoid arthritis sera. Rheumatoid factors of IgG and IgM class were detected by means of a solid-phase radioimmunoassay using formalinized sheep erythrocytes sensitized with rabbit anti-sheep erythrocyte serum and 125I-labelled anti-human IgG or anti-human IgM antibody. 28 of 35 sera and all of 7 synovial fluids of patients with rheumatoid arthritis showed positive reaction for both IgG and IgM rheumatoid factor, though the activity of IgM factor was mostly higher than that of IgG factor. However, rheumatoid factor present in synovial fluids of 3 seronegative patients was mainly of IgG class. Of 14 sera of patient with other collagen diseases, 11 showed IgG and 6 showed IgM rheumatoid factor. The IgG rheumatoid factor seemed to be associated with autologous IgG to form macro-molecular complexes which could be dissociated into 7S molecules of IgG rheumatoid factor and IgG by acid treatment.


Humoral and cellular immunity against allogeneic antigens in patients with acute leukaemia. The humoral and cellular immunity of 12 patients with acute leukaemia (6 AML and 6 ALL) was investigated using several techniques. The study of the humoral response included the screening for allogeneic and autologous lymphocytotoxins, for cytotoxic antibodies against leukaemic blasts, Daudi cells and B lymphocytes and the detection of immune complexes. The cellular immunity was investigated by stimulation of remission lymphocytes by autologous blast cells or allogeneic lymphocytes in mixed cell cultures. Most patients have retained their humoral and cellular immune responsiveness against allogeneic antigens while there seems to be no significant response against leukaemia-associated antigens.


Growth requirements of human mammary epithelial cells in culture. Colony-forming epithelial cells can be separated from the non-dividing "foam cells" in human milk by differential adhesion to glass and freezing. The growth of such partially purified mammary epithelial cells is stimulated by co-culture with non-dividing feeder cells. Foam cells, mitomycin-treated mouse fibroblast lines and human mammary fibroblasts and calf lens epithelial cells are all effective in promoting mammary epithelial cell growth. Contact between epithelial cells and feeders is not required for the growth-promoting effect. The mitogenic effect of epidermal growth factor on mammary epithelial cells also requires feeder cell activity.


Inhibition by interferon of thymidine uptake in chemostat cultures of L1210 cells. Mouse interferon preparations inhibited the incorporation of [3H]-thymidine into acid-insoluble material of mouse leukemia L1210 cells cultivated under steady-state conditions in a chemostat. Interferon exerted only a transitory and less pronounced effect on [3H]-deoxyadenosine incorporation and had no effect on the content of total DNA per cell. Study of [3H]-thymidine uptake at 1 degree into acid-soluble cellular material showed that interferon reduced the uptake of this labeled nucleoside whereas the uptake of [3H]-deoxyadenosine and [3H]-deoxy-D-glucose was not inhibited. The effect of interferon on [3H]-thymidine uptake occurred prior to the inhibitory action on cell multiplication. It is suggested that the inhibitory of [3H]-thymdine uptake reflected specific changes in the cell membrane of interferon-treated cells which may be relevant to the understanding of the antiviral and other biological effects of interferon.


Complete occlusion of the left main coronary artery: successful surgical management by myocardial revascularization. Isolated total occlusion of the left main coronary artery was demonstrated on coronary cineangiography in a 50-year-old woman with a progressive anginal syndrome. Aortocoronary saphenous vein graft bypass was performed. Six weeks after operation the patient was free of symptoms and postoperative coronary angiography showed the graft to be patent.


An induced aliphatic aldehyde dehydrogenase from the bioluminescent bacterium, Beneckea harveyi. Purification and properties. A NAD+-dependent aldehyde dehydrogenase, the activity of which induces at the same time as luceriferase, has been purified from the bioluminescent bacterium Beneckea harveyi, and its chemical and physical properties have been investigated. The purification is accomplished in three steps resulting in an enzyme preparation that gives a single protein band on three different gel electrophoresis systems. The molecular weight of the purified enzyme was estimated to be 120,000 by gel filtration. Sodium dodecyl sulfate-gel electrophoresis gave a molecular weight of 59,000 indicating that aldehyde dehydrogenase has a dimeric structure with subunits of similar molecular weight. The purified enzyme has a high specificity for long chain aliphatic aldehydes; the Michaelis constants for aldehydes decrease with increasing chain length as also observed for bacterial aldehyde dehydrogenases involved in the metabolism of hydrocarbons. The aldehyde specificity of the aldehyde dehydrogenase is similar to that of luciferase indicating that the functional role of the enzyme may be linked with the bioluminescent system.


Intracytoplasmic membrane synthesis in synchronous cell populations of Rhodopseudomonas sphaeroides. Fate of "old" and "new" membrane. A nonspecific density labeling technique has been employed to monitor the synthesis of intracytoplasmic membrane in synchronously dividing populations of Rhodopseudomonas sphaeroides. The intracytoplasmic membranes of cells synchronized in D2O-based medium were found to undergo discontinuous decreases in specific density during synchronous cell growth following transfer to H2O-based medium. These abrupt decreases in membrane specific density occurred immediately prior to cell division and were not observed with intracytoplasmic membranes prepared from asynchronously dividing cells (see also Kowakowski, H., and Kaplan, S. (1974) J. Bacteriol. 118, 1144-1157). Discontinuous increases in the net accumulation of cellular phospholipid were also observed during the synchronous growth of R. sphaeroides. This is to be contrasted to the continuous insertion of protein and the photopigment components of the photosynthetic apparatus into the intracytoplasmic membrane during the cell division cycle (Fraley, R.T., Lueking, D.R., and Kaplan, S. (1978) J. Biol. Chem. 253, 458-464; Wraight, C.A., Lueking, D.R., Fraley, R.T., and Kaplan, S. (1978) J. Biol. Chem. 253, 465-471). Further, examination of the protein/phospholipid ratios of purified intracytoplasmic membrane preparations revealed that this ratio undergoes cyclical changes of 35 to 40% during a normal cycle of cell division. In contrast to the results of Ferretti and Gray ((1968) J. Bacteriol, 95, 1400-1406), DNA synthesis was found to occur in a stepwise manner in synchronously dividing cell populations of R. sphaeroides.


Interactions of alpha1-antitrypsin with trypsin and chymotrypsin. The interaction of alpha1-antitrypsin with trypsin and chymotrypsin has been investigated by protease activity assays, by electrophoretic analysis, by CD and absorption difference spectra, and by gel filtration of reaction mixtures containing excess inhibitor or excess protease. When alpha1-antitrypsin is present in excess, only one stable inhibitor - protease complex is formed. In the presence of excess protease, however, this primary complex is degraded relatively rapidly to one or more secondary complexes. These latter conversions are more pronounced in the case of the antititrypsin-chymotrypsin system. The greater lability of the antitrypsin-chymotrypsin system is evidenced by the relatively rapid release of inactive chymotrypsin from the secondary antitrypsin - chymotrypsin complex. Only minimal amounts of active protease were released from the complexes on the addition of excess protease and one protease could not displace the other from the complex, although competition experiments showed that chymotrypsin reacted more rapidly with the inhibitor than trypsin.


Decreased membrane potassium permeability and transport in human chronic leukemic and tonsillar lymphocytes. Human blood T-lymphocytes increase their potassium (K+) permeability and active K+ transport following lectin or antigen stimulation. We have studied the permeability and active transport of K+ by lymphocytes in chronic lymphocytic leukemia (CLL) to determine if their membrane K+ transport was similar to resting or lectin-stimulated normal blood lymphocytes. K+ transport was assessed both by the rate of isotopic 42K+ uptake and by the rate of change in cell K+ concentration after inhibition of the K+ transport system with ouabain. CLL lymphocytes had a marked decrease in membrane K+ permeability and active transport of K+ when compared to blood T lymphocytes. K+ transport in five subjects with CLL (10 mmol.1 cell water-1.h-1) was half that in normal blood T-lymphocytes (20 mmol.1 cell water-1 h-1). Phytohemagglutinin (PHA) treatment of CLL lymphocytes did not increase significantly their active K+ transport, whereas K+ transport by normal T-lymphocytes increased by 100%. Since there were 73% T-lymphocytes in normal blood and 14% in CLL blood, the difference in membrane K+ turnover could be related either to neoplasia or to the proposed B-lymphocyte origin of CLL. We studied human tonsillar lymphocytes which contained a mean of 34% T-cells. In five studies of tonsils, K+ transport was 14 mmol.1 cell water-1.h-1 and treatment with PHA increased K+ transport only 30%. The intermediate values of basal K+ transport and K+ transport in response to PHA in tonsillar lymphocytes were consistent with the proportion of T-lymphocytes present. These data suggest that B-lymphocytes have reduced membrane permeability and active transport of K+. Thus the marked decrease in CLL lymphocyte membrane K+ permeability and transport may be a reflection of its presumed B-cell origin, rather than a membrane alteration related to malignant transformation.


Proliferation and differentiation of normal granulopoietic cells in continuous bone marrow cultures. Modified conditions are reported for successful continuous bone marrow cultures with stem cell self-renewal and granulocyte-macrophage differentiation. Cells cultured over several weeks were found to be identical to freshly isolated bone marrow cells. Polymorphic neutrophils derived from cultures and primary bone marrow neutrophils both showed C3 AND IgG receptors and both actively phagocytosed foreign particles. Cultured and normal CFU-c were identical, both in their dose responsiveness to CFS and in their sedimentation rate characteristics.


Studies on maximal acid output in patients with abnormal aortic aneurysms. The incidence of co-existent peptic ulceration in a series of 123 patients with abdominal aortic aneurysms was found to be 26%. Following graft replacement of the aneurysm only one patient suffered complications attributable to peptic ulceration in the form of a small haematemesis. The maximal acid output of nineteen patients was compared to sixteen age-matched controls, and suggested that there was no acid hypersecretion associated with abdominal aneurysms. In view of these findings it was felt that vagotomy and pyloroplasty during the aneurysm repair was not warranted, and that instilling Aludrox down the nasogastric tube in the early-post operative period to reduce the amount of free acid was effective in reducing the incidence of significant complications from pre-existing peptic ulceration or stress ulceration.


Preparation of colony stimulating activity from large batches of human urine and  production of antisera against it. In vitro induction of myelopoetic colonies from mouse bone marrow has been used for measurement of leucopoetic colony stimulating activity (CSA) isolated from large batches of human urine. After high flow dialysis in artificial kidneys and immediate adsorption to DEAE-Cellulose, followed by purification on Con A-Sepharose, treatment with insoluble Papain and gelfiltration on Sephadex G 100, enrichment of CSA was about 6,000-fold. An important step of the enrichment procedure was the separation from a CSA-inhibiting protein, probably combining with CSA. Specific activity was further increased by preparative polyacrylamide gel electrophoresis to 5.3 X 10(6) units per mg protein. The total enrichment exceeded 25,000-fold. The final purification product consisted of a group of closely related proteins with high specific activity. Antisera raised with one of the electrophoretic fractions suppressed bioactivity in each of the different purification steps including the final CSA fractions differing in electrophoretic mobility. The antisera furthermore inhibited CSA in human lung and monocyte conditioned media but had only very little effect on partially purified CSA from stimulated human lymphocytes as well as CSA derived from mouse lung conditioned medium.


Long term comparison of fresh arterial allografts and autografts for coronary artery bypass in dogs. Femoral artery grafts were anastomosed end-to-end to the left internal mammary artery proximally and end-to-side to the circumflex coronary artery distally in 21 adult mongrel dogs. Fourteen dogs received allografts and seven received autografts. All autografts studied from one to 11 months were patent. Eleven of the fourteen homografts studied from one to thirteen months were occluded. Histologically, extensive interstitial edema and leukocytic infiltration with subintimal fibrosis and thrombotic occlusion were seen. This study shows that fresh arterial autografts have excellent long term patency, but that most arterial allografts have early thrombotic occlusion.


Antibody-mediated suppression of bone marrow colony formation in vitro. Antisera to mouse brain reacts with hematopoietic stem cells in the mouse bone marrow. We have examined the effect of anti-mouse brain serum (AMBS) on the development of in vitro colonies from mouse bone marrow cells. The addition of 5% AMBS to the cultures markedly decreased the numbers of colonies formed to an average of 10% of the number obtained with normal rabbit serum. AMBS suppressed formation induced by colony stimulating factors (CSF) derived from three different sources; serum from endotoxin treated mice, mouse L-cell conditioned media, and human peripheral mononuclear cell conditioned media. The suppressive activity was quantitatively recovered in the IgG fraction of AMBS. Divalent F(ab')2 fragments were as effective as the intact IgG in decreasing colony formation. Fab fragments were not suppressive. These results suggest that colony formation is induced via a dynamic interaction between CSF and the progenitor cell membrane, and that antibody directed at cell membrane antigen(s) interferes with the generation of the induction signal.


A hypotetraploid human T lymphoid cell line established by cell fusion. A human T lymphoid cell line was established by cell hybridization technique from peripheral blood leucocytes of a patient with Sezary syndrome. The cells beared the surface antigens of human T lymphocyte specificity as demonstrated by immune cytolysis tests, but did not form E rosettes with sheep red blood cells. Isozyme patterns of enzymes in this line such as lactate dehydrogenase, glucose 6-phosphate dehydrogenase and esterase were of human type. The line had 79 chromosomes in modal number. This case supports the proposal that the production of tetraploids is favourable for establishment of cell lines.


Studies of cell subpopulations mediating mitogen hyporesponsiveness in patients with Hodgkin's disease. Hodgkin's disease (HD) is associated with a deficit in T-cell immunity characterized by skin test anergy and decreased lymphocyte responses to phytohemagglutinin (PHA). To investigate this mitogen hyporesponsiveness in HD, we separated peripheral blood mononuclear cells on Ficoll-Hypaque gradients and determined their response to various suboptimal concentrations of PHA. As was expected, patients with HD demonstrated marked mitogen hyporesponsiveness relative to normal controls; however, if the cell suspensions were first passed through glass wool columns to remove adherent cells, the PHA responsiveness of the hyporesponsive HD cells was markedly increased. In contrast, the responsiveness of normal controls was decreased so that the responses of nonadherent normal and HD cells were statistically indistinguishable. Evidently, a glass wool-adherent suppressor cell had been removed from patients with HD, while a glass wool-adherent cell which enhanced mitogenic responses had been removed from normal controls during column passage. Previous to column depletion, patients with HD had decreased proportions of E-rosettes and increased proportions of cells with surface alpha-fetoprotein; however, the proportion of these cells was not changed after column passage. Significant changes with column depletion of glass wool-adherent cells in HD were recorded in the proportions of monocytes (13.2 vs 5.8%) and lymphocytes with C-3 receptors (12.6 vs. 7.8%). The only significant change in normal controls was a decrease in the proportion of monocytes (10 vs. 1.7%). To determine if glass-adherent cells would have a suppressor effect, HD-adherent cells were added in progressively increasing numbers to mononuclear cell suspensions depleted of glass wool-adherent cells. PHA responsiveness returned toward predepletion levels. In summary, patients with HD possess a glass wool-adherent suppressor cell which is responsible at least in part for in vitro mitogen hyporesponsiveness.


Pregnancy and antibody to factor VIII.

Pregnancy and antibody to factor VIII. A patient who had developed a factor VIII antibody three weeks after the birth of her first baby became pregnant for the second time 10 weeks later. The pregnancy was normal apart from extensive spontaneous bruising during the first two months. This bleeding tendency disappeared in the third month of gestation and the antibody became undetectable during the eighth month. It has not reappeared seven months later. An unexplained long bleeding time and low platelet count were noted during the last trimester. The literature on postpartum coagulation inhibitors is reviewed.


Surface marker and other characteristics of Gaucher's cells. A full surface marker study of the splenic storage cells in a case of Gaucher's disease largely substantiates the monocyte/histiocyte nature of Gaucher's cells. In addition, an apparent T-lymphocyte deficiency is demonstrated in the spleen and peripheral blood, and the possible significance of this finding is discussed.


Screening of blood donors for IgA deficiency: a study of the donor population of south-west England. Altogether 29 745 English blood donors were screened for IgA deficiency by double diffusion analysis; 57 had apparent absence of IgA, a frequency of 1:522. Further examination by the more sensitive haemagglutination inhibition assay revealed 34 samples having no detectable IgA, a frequency of 1:875. All donors negative by double diffusion analysis were tested for the presence of antibodies to IgA. Six class specific anti IgA antibodies and four anti IgA antibodies of limited specificity were detected. Three of these had the specificity anti alpha2 and one anti A2m(2). The 34 IgA deficient donors detected provide a source of IgA deficient blood for transfusion to patients with anti IgA antibodies.


A comparison of three rapid methods for the detection of beta-lactamase activity in Haemophilus influenzae. Three methods for rapidly detecting beta-lactamase activity in Haemophilus influenzae are compared. The chromogenic cephalosporin method was found to be the most easily performed and the reagents could be stored for up to three weeks. The phenol red method was simple to perform but the iodometric method was more time consuming. All three tests gave identical results.


Fractionation of human lymphocytes using rosette formation with papain-treated mouse erythrocytes. Human B lymphocytes from rosettes with mouse erythrocytes. If the erythrocytes are pretreated with papain the rosettes are sufficiently stable to allow separation of T and B lymphocytes. The technique is complementary to the sheep erythrocyte rosette method, and gives cell populations with a similar degree of purity.


Increased immune response in the acute phase of systemic lupus erythematosus and psoriatic arthritis caused by serum factors. In the acute phase of systemic lupus erythematosus the serum contains factors, with molecular weights ranging from 780,000 daltons to 1.5 million daltons, which induce blast transformation of autologous lymphocytes. In addition to the high-molecular weight components, low-molecular weight factors (75,000 and 160,000 daltons) which also induce an increase in lymphocytic transformation have also been demonstrated. In contrast to the high-molecular weight components the low-molecular factors stimulate the transformation of autologous and homologous lymphocytes. During transformation, lysis of autologous target fibroblasts occurs. The low-molecular weight mitogenic components remain stable after 30 min at 56 degrees C. The significance of such mediators for the pathogenesis of systemic lupus erythematosus is discussed.


Reactivity of lupus erythematosus antibodies with leukemic helper T cells. Immunoabsorbent columns, containing membrane fragments of either leukemic "helper" T cells or B cell lymphoblasts, were used to isolate and study antilymphocyte antibodies from plasmas of 2 patients with systemic lupus erythematosus (SLE). Both plasmas contained IgG which bound to and could be eluted from the "helper" T cell column. These antibodies significantly inhibited normal lymphocyte proliferative responses to microbial and histocompatibility antigens. The findings indicate that these SLE plasmas contain immunoglobulins of the IgG class which react with leukemic "helper" T cells and inhibit normal effector T cell function.


Human lymphocyte subpopulations defined by double surface markers. Subpopulations of human peripheral blood lymphocytes were studied with single and double surface marker assays. The markers employed were as follows: (1) Fc receptor, using EA, mean 21.4%; (2) C3 receptor, using Zy-C3, mean 14.6%; (3) Slg, using a fluoresceinated F(ab')2 anti-F(ab')2 mean 8.9%; and (4) T lymphocytes forming E-rosette, mean 69.3%. The proportions of lymphocytes with any given surface marker which also have another surface marker were as follows: (1) EA + Slg/EA = 0.14, (2) EA + Zy-C3/EA = 0.22, (3) Slg + Zy-C3/Slg = 0.83, (4) Zy-C3 + E-rosette/E-rosette = 0.02, (5) EA + E-rosette/E-rosette = 0.06, (6) Slg + E-rosette/E-rosette = 0. The relative percentages of cells which were Slg+EA-, EA+Slg-, and EA+Zy-C3- were confirmed by EA rosette depletion via gradient centrifugation. On the basis of these observations, calculations were made of the theoretical numbers of lymphocytes with triple markers (EA+Slg+Zy-C3+ = 3.0%) and lymphocytes with only a single surface marker (EA+ only = 12.5%, Zy-C3+ only = 1.5%, Slg+ only = 1.5%). Finally a schematic representation of the multiple subpopulations of lymphocytes with various surface markers is presented.


A longitudinal chart audit of hypertension in a family practice center. This is a paper in which a practice looks critically at itself through a longitudinal chart audit of 40 patients with hypertension of at least one year's duration. Diagnosis was properly made in all of the patients. The evaluation by physical examination and laboratory studies seemed appropriate and adequate. Therapy was effective. Optimal patient education toward eliminating risk factors was precluded by poor recording of the family history and past medical history of the patient. To overcome these deficiencies a new history data base sheet was designed and a chronic disease flow sheet was developed. This flow sheet is adaptable to any office practice setting and not only affords better patient care, but sets the stage for future prospective studies.


Complications of dorsal column stimulation. The complications associated with 92 dorsal column stimulator implants are reported. They were of two types, technical and functional. In all there were 58 significant complications. Most technical complications were correctable but complications difficult to correct occurred in 26 patients. Late failure in stimulation was observed in 32 implants that had given excellent pain control for periods ranging from months to years. Improvements in the results of this procedure may be achieved by future technical developments and by clarification of physiological mechanisms.


The effect of serotonin precursors on alpha- and gamma-motoneuron activity. The effects of the 5-hydroxytryptamine (5-HT) precursors, 5-hydroxytryptophan (5-HTP) and tryptophan on alpha- and gamma-motoneuron discharges were examined in the spinal cat with a deafferented cord. The injection of 75 mg/kg of dl-5-HTP resulted in a doubling of the spontaneous discharge rate of gamma-motoneurons and the induction of spontaneous alpha-motoneuron activity. These effects of 5-HTP were reversed by the 5-HT antagonists, cinanserin (4 mg/kg) and methysergide (2 mg/kg). Tryptophan alone (100 mg/kg) exhibited minimal effects of motoneuron activity, but in animals pretreated with pargyline it significantly excited alpha- and gamma-motoneurons. Recordings of alpha- and gamma-motoneuron activity in gastrocnemius and semitendinosus nerves revealed that 5-HTP increased alpha- and gamma-motoneuron activity in both flexor and extensor nerves. Reversal of the effects of 5-HTP by 5-HT antagonists suggests that these effects were mediated by 5-HT. The fact that the 5-HTP effects were observed in preparations with an open gamma-loop indicates that the effects on the alpha-motoneurons are not mediated via the gamma-motoneuron facilitation, but results from a central activation.


Pharmacokinetics and effects on fecal blood loss of a controlled release potassium chloride tablet. A slow-release tablet containing 12.5 mEq of potassium chloride was compared with a potassium chloride solution in normal human subjects under controlled conditions. Changes in plasma potassium concentration and rates of urinary potassium excretion indicate the tablet is absorbed in a slow, sustained fashion in contrast to the solution. Net potassium excretion after single and multiple doses indicates that the amount of potassium absorbed from the slow-release tablet is comparable to the solution. The slow-release potassium chloride tablets were well tolerated and were effective in correcting experimentally induced potassium depletion of moderate severity. Gastrointestinal tract irritation was not apparent and fecal 51Cr red blood cell loss after the tablet and the solution were of the same order.


A comparison of ion concentrations, potentials and conductances of amphibian, bovine and cephalopod lenses. 1. The concentrations of sodium, potassium and chloride in frog and bovine lenses showed a normal intracellular ion distribution with the sum of the internal cations approximately equal to the external sum. In the cephalopod lens, however, the sum inside was much lower than that outside.2. The membrane potentials of frog, Sepiola and bovine lenses were -63, -63 and -23 mV respectively. A comparison of the electrical data with the Nernst potentials predicted from ion concentration data indicated that sodium and chloride ions as well as potassium contributed to the membrane potential in frog and bovine. In contrast, the membrane and Nernst potentials for potassium were equal in Sepiola.3. Substituting potassium for sodium in the external medium depolarized lens potentials in all three species. Estimates of the relative permeabilities of sodium, potassium and chloride were obtained by fitting the Goldman-Hodgkin-Katz equation to the potential data.4. The potassium permeability was determined directly by (42)K efflux measurements and values of 2.99, 9.83 and 3.13 (x (-8) m sec(-1)) were obtained for frog, Sepiola and bovine lenses respectively.5. The effect of raising external potassium on the efflux rate constant was determined and there was reasonable agreement between experiment and theory (Kimizuka-Koketsu) in frog and bovine lenses, but the Sepiola data indicated that the potassium permeability decreased by a factor of 2.6 when the external potassium was raised from 10 to 120 mM-K+.6. The measured specific conductances, obtained using two internal micro-electrodes, were 7.7, 15.9 and 9.9 (Sm(-2)) for frog, cephalopod and bovine lenses respectively. These data compare with computed values (Kimizuka-Koketsu theory) of 7.5, 14.1 and 17.2 (Sm(-2)).7. The effect of increasing external potassium on the conductance was also tested and there was good agreement between experiment and theory (assuming constant permeabilities) only in the amphibian lens. However, when the cephalopod data were corrected assuming a 2.6-fold decrease in P(K) for a twelvefold increase in potassium, then there was excellent agreement between experiment and theory.8. The bovine measured conductances were much lower than the theoretical values throughout the range of external potassium concentrations and several explanations were proposed to account for the discrepancies.


The effects of manganese ions on the contraction of the frog's heart. 1. The effects of Mn(2+) in particular but also of Ni(2+), Co(2+), Cd(2+), verapamil and D600 on the contraction of isolated frog atrial trabeculae have been investigated. Contraction was initiated either by electrical stimulation, or by raising the [K](o) or by lowering the [Na](o).2. Mn ions like Ca ions cause a hyperpolarization of the cell membrane and a rise in the threshold for the action potential and twitch. Mn ions, particularly at low concentrations, reduce the overshoot of the ventricular action potential.3. Mn ions reduce the strength of the regularly evoked heart beats. Prolonged exposure, in beating hearts, results in a rise in resting tension and often a small recovery of the heart beat.4. In normal Ringer solution and in Ringer free of Na ions, the addition of Mn causes the tension-depolarization curve to be displaced by an amount equivalent to an 18 mV hyperpolarization of the membrane potential for a tenfold increase in the divalent cation concentration.5. Mn, Co, Ni and Cd ions all cause a marked reduction in the tension generated by exclusion of Na ions from the bathing fluid. In the presence of these divalent cations the contracture divides into an initial phasic and a later tonic contraction. This inhibition is reversed by raising the [Ca](o), while the tension developed during the initial phasic contraction varies with the [Ca](o)/[Mn](o) quotient.6. A similar tonic contracture is initiated after exposure to Na-free fluid containing a high [Mn](o) by the addition of a small concentration of Na, Li, hydrazinium or hydroxylammonium ions.7. The organic ;Ca antagonists' verapamil and D600 have little effect on the contracture induced by lowering [Na](o) even after prolonged exposure at relatively high concentrations but they do inhibit the twitch contraction and the K contractures.8. The effects of Mn on the Na-withdrawal contracture of frog heart can be interpreted in terms of an exclusively extracellular effect where Mn ions resemble Na ions in their action, and both antagonize the movement of Ca across the cell membrane.9. The experimental evidence suggests that the K contracture in frog heart is initiated by a mechanism which is, in some ways different to that underlying the Na-withdrawal contracture, and may involve two different sources of activator Ca.10. The several different effects of Mn on the frog heart probably reflects the ability of this cation to interfere with many processes involving Ca, and that there are a number of such processes involved in the results described in this work. The effects of Mn are more complex than might be generally supposed.


Uptake and loss of manganese from perfused frog ventricles. 1. The uptake and loss of Mn has been studied in perfused isolated frog ventricles, at rest, during activity, in Na-free fluid and in K-rich fluid. 2. In normal Ringer the uptake of Mn with time is composed of two phases which can be interpreted as an initial saturating phase and a slower non-saturating phase. The uptake in the resting heart is estimated to be 1.91 X 10(-14) M.cm-2.sec-1, and the extra uptake associated with the action potential to be 6.90 X 10(-13) M.cm-2.beat-1, when the heart is exposed to Ringer containing 8 mM-Mn. 3. The washout of Mn from preloaded ventricles into Mn-free Ringer is composed of at least two exponential phases. The slowest phase corresponding to a rate of Mn efflux of 1.72 X 10(-14) M.cm-2.sec-1. 4. Mn uptake is not increased by exposure of the muscle to Na-free fluids but is markedly increased by exposure to depolarizing fluids. 5. The Mn accumulating in the ventricles during a 7 1/2 min exposure to 8 mM-Mn-ringer with an elevated [K], increases with increasing [K]o to reach a peak at 75 mM-K and then falls to quite a low value in 120 mM-K. 6. The results are discussed in the light of the action of Mn ions on the contraction and the ionic currents of frog heart muscle.


Production of corticotrophin releasing hormone by the isolated hypothalamus of the rat. 1. The ability of the rat hypothalamus to produce corticotrophin releasing hormone (CRH) in vitro was studied in the presence and absence of neurotransmitter substances, angiotensin and corticosterone. 2. Acetylcholine, 5-hydroxytryptamine (5-HT) and angiotensin II increased hypothalamic CRH release and content. 3. Noradrenaline and glycine decreased the spontaneous release of CRH from the hypothalamus but neither of these substances affected hypothalamic CRH content. 4. Dopamine, GABA, adrenaline, melatonin, histamine, glutamic acid and corticosterone did not affect the basal CRH activity of the hypothalamus in vitro. 5. Noradrenaline, GABA and corticosterone reduced the acetylcholine- and 5-HT-induced increases in the release of CRH from the hypothalamus. The rises in CRH content induced by acetylcholine and 5-HT were also reduced by noradrenaline and GABA but increased by corticosterone. 6. The physiological significance of the results and the potential value of the technique are discussed.


Lower gastrointestinal bleeding: an unusual presentation for blunt abdominal trauma. A case of mesenteric vascular injury secondary to nonpenetrating steering wheel abdominal trauma is presented. Unique to this report is the presentation of blunt abdominal trauma as acute lower gastrointestinal bleeding with demonstration of the lesion preoperatively via selective celiac and superior mesenteric arteriography.


[X-ray pictures in pneumonia caused by Pneumocystis carinii. Nine cases of immunodepressed patients (author's transl)]. The authors analyse the pulmonary symptoms found by X-Ray in nine immunodepressed patients who were hosts to Pneumocystis carinii. The radiological abnormalities do not generally appear early nor are they specific; the syndrome of diffuse alveolar consolidation only appears at a late stage, it is most serious in the base and the peri-hilar regions, but does not affect the apex. It would appear that no prognostic value can be ascribed to the radiological results. The authors therefore suggest bronchial scanning for tracking down the Pneumocystis whenever suspicious clinical symptoms appear.


The role of CT scanning in the diagnosis of acoustic neuromas. CT scanning has an important role as a prime investigate technique in the patient with hearing loss and/or vestibular dysfunction. Lesions larger than two cm in size should be further investigated by angiography. Myelography of the posterior fossa remains the only test that can exclude an acoustic neuroma if small or if there is a negative CT scan. Plain films and tomography are used to exclude other lesions.


[Aqueous humor levels of gentamicin after parenteral, subconjunctival and topical administration (aithor's transl)]. The purpose of this study was to determine the concentration of Gentamicin in blood serum and primary aqueous humor at varying periods of time after intravenous, intramuscular, subconjunctival and topical administration of Gentamicin. Therapeutic effective levels in primary aqueous humor were measured only after subconjunctival injections. The only broad spectrum antibiotics are the aminoglykosides Gentamicin, Tobramycin, Sisomicin and Amikacin. For prompt treatment of bacterial endophthalmitis without bacterial culture and antibiotic sensitivity testing therefore subconjunctival injection of Gentamicin is necessary.


[Electrophysiological and fluorescence-angiographical examinations in a case of fundus albipunctatus cum hemeralopia congenita (author's transl)]. Electrophysiological and fluorescenceangiographical examinations were carried out in a case of fundus albipunctatus cum hemeralopia congenita. In the ERG a diminished scotopic b-wave was conspicuous, which reached the normal size after longer dark adaptation. It was possible to distinguish between albipunctatus-dots and druses by fluorescenceangiography. While the latter became clearly visible in the phase of choroidic-fluorescence the ophthalmoscopically perceptible albipunctatus-dots lost their visibility.


[The fluorescein angiogram in choroidermia (author's transl)]. The fluorescein angiogram makes a widespread degeneration of the retinal pigment epithelium in choroidermia visible. In the female carriers it shows a spot-like picture. This method of examination contributes to the interpretation of the pathogeny and differential diagnosis.


[Senile lattice structures in the parenchym of the cornea (author's transl)]. Sharply limited, intersecting, optically void, dark appearing lines in the parenchym of the cornea of elder patients may be called senile lattice work. They are presumably caused by general decay, they are benign and do not impair the visual faculty. A knowledge of them is of significance for differential diagnosis.