Immunofluorescent localisation of enterokinase in human small intestine. The distribution of enterokinase in human intestine was studied in operative mucosal biopsies using specific antiserum to human enterokinase, previously purified to apparent homogeneity by affinity chromatography and immunoabsorption. Fluorescence was observed in the brush-border and glycocalyx of the duodenum and proximal 15 cm of jejunum distal to the D/J flexure. Distal jejunum and ileum as well as stomach and colon were consistently negative. Brunner's glands and goblet cells were never stained by specific antibody. Preliminary evidence was obtained that the human enterokinase molecule contains a specific antigenic determinant in its polypeptide component and a second determinant in the oligosaccharide moiety which cross-reacts with blood group A. Preliminary evidence was also obtained that mucosal synthesis of enterokinase may be impaired in jaundice due to carcinoma of the pancreas and induced in the small intestine distal to the normal limit of synthesis after pancreatico-duodenectomy.


Enzymatic and morphometric evidence for Crohn's disease as a diffuse lesion of the gastrointestinal tract. Intestinal disaccharidase and dipeptidase activities were measured in mucosal biopsies from the proximal jejunum in 20 patients with Crohn's disease apparently confined to the distal ileum or large bowel, 14 patients with ulcerative colitis, and 14 healthy volunteers who acted as controls. The dissecting microscopy and histological appearance of the biopsies were normal (Gd 0-1) except for two which showed grade 2 changes. tbiopsy morphometry showed a reduction of jejunal mucosal surface area and an increase in mucosal volume in patients with Chron's disease when compared with the other two groups. The mucosal enzymes studies demonstrated that patients with Crohn's disease had a significant reduction in brush-border enzymes (disaccharidase) but no change in cytoplasmic enzyme activity (dipeptidases). The enzyme levels in patients with ulcerative colitis did not differ from the healthy controls. The reduction of brush-border enzymes with normal cytoplasmic enzymes in the presence of abnormal morphometry is further evidence of the concept of Crohn's disease as a diffuse lesion of the gastrointestinal tract. It also suggests that there is either specific damage to the microvilli or some other abnormality such as impairment of enzyme synthesis.


Neuronal lipofuscin in centrophenoxine treated rats. The diminution of neuronal lipofuscin was studied in centrophenoxine adminstered animals. In fluorescent studies, as well as in ordinary histological methods, a marked decrease of the lipofuscin was observed in the cerebral cortex, hippocampus, thalamus, basal ganglia, midbrain, medulla oblongata and spinal cord. The lipofuscin in the cenntrophenoxine animals showed fine granular structures in the perikarua of the neurones when compared to that of control rats. Electronmicroscopically, electron density of the lipofusin structures was observed. Enlargement of the vacuolar portions of the lipofuscin was seen in the neurones of the dorsal ganglia in the centrophenoxine animals. In the present studies, the diminution of the lipofuscin in the neurones was well demonstrated with fluorecent and histological methods. The characteristic ultrastructural changes of the neuronal lipofuscin are reported.


Plasma proinsulin-like components and insulin in chronic liver disease. In order to explain the increase of total IRI frequently observed at basal status, and after glucose administration, in patients with chronic liver disease, plasma proinsulin-like component and insulin levels have been studied in fourteen patients with liver cirrhosis associated or not with clinical or subclinical diabetes mellitus. A significative increase of plasma insulin was observed at basal status and after a glucose load not only in subjects with clinical or subclinical diabetes but also in those patients without carbohydrate abnormalities. This increase is apparently not correlated to any clinical characteristic and is associated in fasting and after glucose load with increased proinsulin-like component levels especially in patients with clinical or subclinical diabetes.


Localization of a low molecular weight protease inhibitor to tracheal and mixillary sinus mucosa. Normal human bronchial secretion contains protease inhibitors from plasma and an acid-stable, low molecular weight inhibitor which strongly inactivates granulocyte elastase and chymotrypsin-like cationic proteins. The distribution of this bronchial protease inhibitor in tracheal mucosa was analyzed by an indirect immunoperoxidase method. Strong peroxidase staining was obtained in the columnar ciliated epithelium of the trachea and in the sero-mucus glands. The findings support a local mucosal production of the inhibitor. Maxillary sinus mucosa was also positively stained for the inhibitor.


Inhibition of ribonucleases by ribonucleotides and transition state analogs in cell-free extracts from Ehrlich ascites tumor cells. We investigated the ribonucleolytic breakdown of poly(U), poly(A), RNA trascribed from calf thymus DNA with E. coli RNA polymerase, ribosomal RNA, tRNA and mengovirus RNA by an enzyme fraction obrained from a postribosomal supernatant of Ehrlich ascites tumor cells. The single-stranded homopolyribonucleotides are preferentially degraded by the enzyme fraction with the production of ribonucleoside 5'-monophosphates. The RNase activity is completely dependent on the presence of Mg2+ ions and is highest at Mg2+ and K+ concentrations optimal for cell-free protein synthesis. Ribonucleoside 5'-monophosphates, ribonucleoside 2'(3')-monophosphates, ribonucleoside 2'(3'),5'-bisphosphates and transition state analogs consisting of vanadyl sulfate and either ribonucleosides or ribonucleoside 5'-monophosphates in a molar ratio 1:1 inhibit the ribonucleolytic activity of the enzyme fraction. The ribonucleoside 2'(3'),5'-bisphosphates and the transition state analogs are the most effective inhibitors. However, only in the presence of ribonucleoside 2'(3'),5'-bisphosphates a concomitant stimulation by 50 to 60% of poly(U)-directed polyphenylalanine synthesis is observed; all the other RNase inhibitors tested also inhibit polypeptide synthesis. The results of preliminary experiments show that poly(U) and ribonucleoside 2'(3'),5'-bisphosphates are well suited as ligands for affinity chromatography of ribonucleases from Ehrlich ascites tumor cells.


The macrophage disappearance reaction (mdr) as an in vivo test of delayed hypersensitivity in mice. The macrophage disappearance reaction (MDR), as an invivo analogue of in vitro tests for delayed hypersensitivity, was utilized in mice with M. tuberculosis or mouse thyroid extract (MTE). The optimal schedule for the induction of macrophages in peritoneal exudates and the optimal concentration of antigen for the MDR were determined. Macrophage disappearance occurred 4 h after immunized mice received an intraperitoneal injection of 200 microng of soluble antigen. The MDR was found to be antigen specific. Intraperitoneal injection  of an unrelated antigen or tissue culture medium alone did not cause macrophage disappearance; however, the re-injection of the antigen used for immunization caused a 70-80% reduction of macrophages. Macrophage disappearance was greater in mice immunized with M. tuberculosis than in mice immunized with MTE. Comparison of the MDR with the footpad test in these 2 groups showed that mice immunized with M. tuberculosis developed a higher degree of delayed hypersensitivity than the group immunized with MTE. These results demonstrate that the MDR represents a specific and quantitative method for detecting the delayed type of cellular immune response in mice.


Complement receptors and cell associated complement components. Membrane receptors for activated complement components are widely distributed amongst tissue cells of most mammalian species. Common amongst these are receptors for C3b which mediate many of the biological functions of C3. In addition, the genetic control of certain complement components is linked to the genes which code for the major histocompatibility complex. Many of these components are also present on cell surfaces. This suggests that the function of the complement system and the major histocompatibility complex may be related.


Development of a localized hemolysis-in-gel assay for Vi antigen: characterization of the Vi-specific PFC response of nude and normal mice. An assay to detect specific plaque-forming cells (PFC) to Vi antigen (Vi) was developed and the optimal conditions for sensitization of sheep erythrocytes (SE) and plaque development were determined. Using PFC and passive hemagglutination (PHA) assays, Vi-specific immune responses of athymic (nude) and normal mice were characterized. Vi was found to elicit only IgM PFC. No discernable secondary response was detected following a second injection of antigen. Nude and normal mice responded in a quantitatively similar manner to all doses of Vi tested and responded similarly on varying days following immunization. Also, both nude and normal mice produced the greatest number of Vi-specific PFC 4 days following immunization with an optimally immunogenic dose of Vi (1.0 microng/mouse). These results indicate that functional thymus-derived cells are not necessary to elicit an immune response against Vi antigen.


Induction of avian immunological responsiveness following cloacal drinking of immunogen. A solution of human serum albumin which has been cloacally ingested can cause effective development of immunological memory with minimal or no immediate production of antibody in 4 to 6 week old chickens. Such memory production was not accompanied by the generation of circulating rosette-forming ABC (antigen binding cells) and thus the peripheral appearance of such cells as a part of the normal primary response to HSA (human serum albumin) does not accord with the interpretation that they represent memory B cells. The cloacal route may be important for the maturing chick in initiating immunity to the food and micro-organisms of its external environment and gut flora.


Non-specific suppression of the initiation of the immune response to a heterologous immunogen by supernatants from specifically stimulated, primed lymphoid cells. In cultures of spleen cells from mice immunized with horse erythrocytes (HRBC) 7 days earlier, the simultaneous addition of sheep erythrocytes (SRBC) and the priming antigen on day 0 resulted in the suppression of the anti-SRBC plaque-forming cell (PFC) response by day 5 compared to the response of similar cultures that received only SRBC. The cell-free culture fluid from specifically-stimulated, HRBC-primed cells, but not normal cells, contained a factor that nonspecifically inhibited the anti-SRBC PFC response of cultures of normal spleen cells to which SRBC and diluted supernatant aliquots were added at the beginning of culture. Suppressor activity was not manifest unless active supernatants were added on day 0 of a 5-day culture period. Inhibition of the reference plaque response was not due to cytotoxicity of the active material, decreased immunogenicity of the SRBC, or switchover from IgM to IgG plaque formation. The soluble mediator was released slowly into the culture fluid, with linear kinetics, from specifically activated, primed cells, with maximum suppression obtained with the 120-h supernatant. When active supernatants were fractionated by gel filtration over Sephadex G-150, the inhibitory factor eluted with molecules of about 34,000 mol. wt.


Reactivity and crossreactivity of mouse helper T cells to malaria parasites. The mouse helper T-cell response to four plasmodial and babesial parasites was measured by using them as carriers for a standard hapten (TNP). Helper T cells appeared to recognize all the parasites, but not to be able to distinguish between them. Helper T-cell responses could be augmented by vaccination with formalin-fixed parasites. However vaccination did not always confer protection against infection. Conversely, mice resistant to infection because of prior recovery from a homologous or heterologous infection had normal or reduced helper T-cell responses. It is concluded that resistance to infection with these parasites, though dependent on T cells, may not only involve the helper T-cell subpopulation.


Immunological capacity of the chicken embryo. II. Humoral immune responses in embryos and young chickens bursectomized and sham-bursectomized at 52--64 h of incubation. White Rock embryos surgically "bursectomized" at 52--64 h of incubation, and shambursectomized embryos were injected with 10(6) guinea-pig red blood cells on day 12 of incubation, and tested for plaque-forming cells and serum haemagglutinins 3, 5, 7, 10, 15 and 19 days after immunization, i.e. as 15- to 19-day-old embryos and 1- to 10-day-old chickens. The number of natural plaque-forming cells detected by direct or indirect techniques was small in nonimmunized shambursectomized and bursectomized embryos, but increased in very young chickens. The injection of guinea-pig red blood cells induced a significant increase in the number of direct and indirect plaque-forming cells in the spleen of bursectomized and sham-bursectomized embryos and chickens. Agglutination of papain-treated guinea-pig red blood cells and indirect anti-chicken globulin (Coombs) test revealed the presence of natural agglutinins for guinea-pig and for sheep erythrocytes in non-immunized sham-and bursectomized embryos. A small number of sera from nonimmunized bursectomized and sham-bursectomized embryos contained IgM. The immunization with guinea-pig red blood cells increased the antibody production in both bursectomized and sham-bursectomized embryos and chickens. Sham-bursectomized embryos responded better to antigenic stimulation than bursectomized embryos. The injection of guinea-pig red blood produced an enlargement of the spleen only in bursectomized embryos and chickens. The first plasma cells appeared in nonimmunized sham-and bursectomized 6-day-old chickens. The number of plasma cells increased in chickens immunized as embryos. Cytomorphological analysis of the thymus, bone marrow and liver did not reveal apparent differences between bursectomized, sham-bursectomized embryos and very young chickens. It has been postulated that the chicken embryo has an antibody-producing system composed of the bursal and the nonbursal (or accessory "bursal") microenvironment, the latter being bursa-independent. The final microenvironmental network for the formation of Bu lymphocytes is the result of coordinated activities of a variety of intrinsic cellular and humoral factors.


Heteroantisera prepared against B lymphocytes at different stages of differentiation. II. Functional analysis of cytotoxicity to different B-cell populations. Functional studies on heteroantisera raised against mouse B cells in rabbits suggest a correlation between thymus-independent B cells and LPS-responsive B cells, and differences in either from thymus-dependent B cells. Furthermore it seems possible to follow B-lymphocyte differentiation from antigen-uncommitted precursors to antigen committed immature B cells to mature B lymphocytes by the loss and acquisition of surface markers distinguished by these heteroantisera. Additional evidence is provided that there are distinctive antigenic differences between antibody forming cells raised from the same B-cell source after in vivo or in vitro immunization.


Intestinal immune response to E. coli antigens in the germ-free chicken. The secretory intestinal immune response to live and heat-inactivated E. coli 02 has been studied in young germ-free chicks. A response to live organisms was evident from an infiltration of the intestinal mucosa with IgA and IgM immunoglobulin-producing cells (IPC). Antibody associated with both immunoglobulin classes which was specific for E. coli 02 was demonstrated in saline extracts of contents from the small intestine. Repeated oral immunization with heat-killed E. coli 02 failed to stimulate serum or intestinal antibody. This finding reflected the complete absence of IPC within the intestinal mucosa of these birds. The IPC profile of unimmunized germ-free chicks was identical to that seen in chicks orally immunized with inactivated E. coli. An interesting feature of all gnotobiotic birds was a considerable elevation of serum IgM levels, compared to those of conventional birds, which was unassociated with immunization procedures. Serum IgG and IgA levels in gnotobiotes were much lower than those in the serum of conventional birds of comparable age. Studies on the fate of orally administered antigen using radiolabelled E. coli endotoxin indicated that a proportion remained intact as far down the intestinal tract as the caecum. However, unaccountably high levels of low mol. wt antigen in the faeces suggested degradation, intestinal absorption and subsequent excretion of endotoxin fragments in the urine. The differences between the avian response and that observed in mammals are discussed in relation to the comparative roles of Peyer's patches and the bursa of Fabricius in initiating intestinal immununity.


Inhibition of antibody responses by cells from mice treated with picryl sulphonic acid. Cells from mice inoculated with picryl sulphonic acid (PSA cells), which contain suppressor T cells for contact sensitivity to picryl chloride, were examined for their ability to alter antibody responses of normal mice. These cells did not influence antibody or plaque-forming cell (PFC) production accompanying contact sensitivity reactions produced by painting with picryl chloride but reduced IgG antibody and indirect PFC responses to conjugates of trinitrophenyl (TNP) bovine serum albumin and ovalbumin. IgG responses to TNP or new antigenic determinants of TNP-mouse serum albumin were not affected by PSA cells. The PSA cells required several weeks to produce reductions of responses and only reduced responses to optimal doses of antigen. When the injection of antigen was delayed until several weeks after the injection of PSA cells rapid reductions of responses were found but these were short-lived. The inhibition was specific for TNP proteins although responses to hapten and carrier were reduced. Evidence is presented to show that the inhibition was mediated by an adherent macrophage-like cell rather than a T cell. The inhibitory activity was resistant to irradiation and anti-theta treatment but was removed by glutaraldehyde treatment and cotton wool filtration.


Antigenic competition between heterologous erythrocytes in mice. Immunological and histological studies exploring mechanisms of the antigenic competition. To explore the mechanisms of antigenic competition, immunological and histological studies were made on mice using non-crossreacting heterologous erythrocyte antigens, i.e. sheep (SRBC), horse (HRBC) and chicken (CRBC) erythrocytes. Deficiency in the competition-inducing capacity of CRBC which we demonstrated in a previous paper was corroborated by the results that under any experimental conditions examined CRBC were unable to induce the competition. Of interest in the studies was that when anti-HRBC antibody responses of mice pre-injected with SRBC, i.e. competing antigen, were examined on day 2 and day 4 of HRBC-immunization, the day-2 response was revealed to be significantly enhanced, whereas the day-4-response was markedly suppressed as a result of the antigenic competition. By contrast, pre-injection with CRBC, i.e. non-competing antigen, did not affect at all either day-2 or day-4 anti-HRBC response of mice. Histological features of the spleens of mice either being prepared for antigenic competition or undergoing competitively suppressed antibody response were characterized by prominent regeneration of hyperplastic germinal centres, involving appearance of numerous tingible bodies and distinct collars of small lymphocytes which suggested massive proliferation and degeneration of lymphocytes. The spleens of mice in the immunological state indifferent to antigenic competition were characterized by huge lymphatic follicles which contained very few tingible bodies and were circumscribed by a markedly attenuated zone of small lymphocytes. From all these results, we suggest that massive proliferation and differentiation of T lymphocytes, probably toward regulatory (suppressor) T cells, could account for a mechanism of antigenic competition, and that deficient competition-inducing capacity of CRBC should be ascribed to weakness of their capacity in activation of the regulatory T lymphocytes.


B-memory cells can be stimulated by antigen in vitro to become IgG antibody-secreting cells. Whereas DNP-KLH primed mouse spleen cells fail to show the high IgG anti DNP levels characteristic of an anamnestic immune response when cultured for 5 days under Mishell-Dutton conditions, we show here that such a response can be observed after 8--10 days in vitro using modified Marbrook culture vessels. The kinetics of this secondary response in vitro resemble that described elsewhere for the adotpive secondary immune response in irradiated recipients, and show that insignificant numbers of IgG PFC can be expected before 6 days of culture. This timing is governed by the maturation state of B cells at the start of culture, and was not accelerated by the addition of recently boosted carrier primed spleen cells. We conclude that the deficit in IgG PFC numbers that characterizes Mishell-Dutton cultures of cells primed 2--4 months previously is due to the shortage of time during which such cultures can maintain lymphocyte division and maturation.


Conditions for the development of IgM- and IgG-antibody-secreting cells from primed mouse splenocytes in vitro. A modified Marbrook chamber has been devised and manufactured which will fit inside a standard tissue culture Petri dish. A comparison has been made between Mishell-Dutton and modified Marbrook culture systems with respect to their ability to support an immune response by quiescent memory cells exposed to antigen in vitro. Good culture conditions are maintained for considerably longer in the modified Marbrook cultures and it seems that as a consequence these cultures support a large and reliable IgG response, normally absent or very small in cultures of the Mishell-Dutton type. Ease of manipulation and convenient size make the modified Marbrook system a good prospect for future long-term experiments.


Antibody response in vitro of spleen cells from Plasmodium yoelii-infected mice. The primary antibody response to sheep erythrocytes and dinitrophenylated Ficoll of spleen cells from mice infected with Plasmodium yoelii was studied in vitro. The response to sheep erythrocytes was enhanced between 2 and 4 days after infection and depressed at later intervals. Cell fractionation experiments carried out at the time of immunosuppression indicated a defect of macrophage function. At the same time the response to dinitrophenylated Ficoll was normal.


Use of a free viral immunofluorescence assay to detect human reovirus-like agent in human stools. Human reovirus-like agent (HRVLA) is a major cause of gastroenteritis in infants and young children in many parts of the world. Detection of HRVLA in stools is impractical with the techniques currently available. We describe a rapid immunofluorescence assay for detection of HRVLA in stools. Results with this assay agreed well with results obtained from examination of stool specimens by electron microscopy.


Inhibition of small-intestinal sugar and amino acid transport by the enterotoxin of Shigella dysenteriae I. The enterotoxin of Shigella dysenteriae I produces fluid and electrolyte secretion in the rabbit ileum. These present studies were designed to evaluate nonelectrolyte transport in rabbit ileal mucosa exposed to Shigella enterotoxin. Both 10 mM galactose and 5 mM L-alanine absorptions were significantly impaired in enterotoxin-exposed ileal mucosa compared with control mucosa. L-Alanine influx was not imparied in two other secretory processes: that induced by cholera enterotoxin and hyperosmolarity. These studies provide evidence that both surgar and amino acid absorptions are diminished in the small intestine by the enterotoxin of S. dysenteriae I.


Appearance of cellular and humoral immunity in guinea pigs after infection with Coxiella burnetii administered in small-particle aerosols. The development of humoral and cell-mediated immune responses was studied in guinea pigs infected with Coxiella burnetti administered in small-particle aerosols. Direct macrophage migration inhibition was observed in cultured peritoneal exudate cells as early as 3 days after exposure. Maximum inhibition of macrophages cultured with phase I or II antigen occurred 14 to 21 days postexposure and persisted through 35 days. This inhibitory action was no longer detectable at 42 days. Serum antibody to the phase II antigen of C. burnetii was detected at 14 days, and serum antibody to phase I antigen was detected at 21 days, 18 days after the cell-mediated immune response.


Bacterial lipopolysaccharide induction of a mouse spleen factor stimulating ribonucleic acid polymerase II. When bacterial lipopolysaccharide, a B-cell mitogen, was injected intraperitoneally into mice, the rate of deoxyribonucleic acid synthesis and the number of antibody-secreting cells in the spleen increased simultaneously, reaching a maximum in 3 days. The rate of ribonucleic acid synthesis also increased during this period, and this was found to be due to activation of alpha-amanitin-sensitive transcription in lymphoid cells of the spleen. The factors stimulating ribonucleic acid polymerase II in the spleens of normal mice and those treated with lipopolysaccharide were compared, and an additional factor besides that present in normal spleens was found in the spleen of lipopolysaccharide-treated mice.


Serological cross-reactivity between group B Streptococcus and Sporothrix schenckii, Ceratocystis species, and Graphium species. Serological cross-reactivity of a group B Streptococcus (H36B) with Sporothrix schenckii and 39 different Ceratocystis and Graphium species was investigated by double immunodiffusion. Rabbit anti-H36B serum reacted with antigens from S. schenckii and from 36 of 39 Ceratocystis and Graphium species. It is speculated that low-titer agglutinins to S. schenckii in normal sera are due to antibodies raised against various bacteria which share common antigens with S. schenckii.


Effect of levamisole on Mycobacterium leprae in mice. Levamisole, an antihelminthic drug that is capable of enhancing immune responses in mice and in humans, was tested in experimental Mycobacterium leprae infections in mice by a number of schedules. Intermittent schedules were used, and administration of the drug was started (i) around the time of inoculation with M. leprae, (ii) when the M. leprae population was approaching the plateau level, (iii) after the onset of the plateau phase, or (iv) after BCG vaccination 28 days following the inoculation with M. leprae. No effect of drug could be discerned with any of the schedules.


Bacterial interference. IV. Epidemiological determinants of the antagonistic activity of the normal throat flora against group A streptococci. A study was performed to identify epidemiological factors such as age, race, sex, and time of culture that might influence the ability of the normal pharyngeal flora to interfere with growth of group A streptococci. From March 1974 through February 1975, throat swabs were obtained from 952 individuals. Cultures were assayed by an agar overlay procedure for the presence of bacteria capable of inhibiting growth of group A streptococci. The observed inhibition was then determined to be bacteriostatic or bactericidal by use of a broth filtrate technique. Regardless of age, race, or sex, subjects were more likely to harbor interfering flora if cultured during the months of March and April, which coincided with the highest prevalence of group A streptococci in the community. Race and sex of subjects appeared not to influence the inhibitory activity of throat flora either quantitatively or qualitatively. However, among individuals with interfering flora, the prevalence of bactericidal organisms increased and bacteriostatic organisms decreased with advancing age. Since the presence of bactericidal, and not bacteriostatic, organisms has been associated with resistance to colonization of the throat by group A streptococci, this higher prevalence of bactericidal organisms in older individuals suggests that bacterial interference may be one of the mechanisms that account for the greater resistance of adults than children to streptococcal throat infection.


Interaction of lipoteichoic acid of group A streptococci with human platelets. The interaction of group A streptococcal lipoteichoic acid (LTA) with mammalian cell membranes was studied in human platelets. The binding of LTA to platelets was platelet concentration and time dependent. Binding approached a maximum within 10 min of incubation. The bound LTA could be displaced by adding a 50-fold excess of unlabeled LTA. An association constant of 1.9 X 10(-7) M was calculated, and only one population of binding sites was detected. Immuno-ferritin labeling of LTA-treated platelets demonstrated a patchy distribution of LTA binding sites on the platelet surface. LTA inhibited collagen- and alpha1 chain-induced platelet aggregation, but not the platelet release reaction, suggesting that the LTA and collagen binding sites on human platelets are distinct. Apparently, LTA binds to platelets and interferes with collagen-induced aggregation although collagen is still able to attach to binding sites to trigger the release reaction.


Production and assay of antibodies against one antigenic component of Mycobacterium bovis BCG. Monospecific antisera against BCG antigen 60 were produced by all of four rabbits during immunization with precipitates containing antigen 60 cut out of gels after crossed immunoelectrophoresis. During electrolytic iodination of a crude antigen 60 preparation, preferential labeling of antigen 60 was demonstrated, and a specific radioimmunoassay was established to follow the development of anti-BCG-60 activity during immunization.


Purification and characterization of group A streptococcal pyrogenic exotoxin type C. Group A streptococcal pyrogenic exotoxin (SPE) type C was partially purified by differential solubility in ethanol and acetate-buffered saline. Toxin prepared in this way consisted of protein and hyaluronic acid. After removal of hyaluronic acid, the toxin remained pyrogenic, enhanced susceptibility of rabbits to letahl endotoxin shock, was stable when treated with acid, base, or pepsin, but was inactivated by heat. Toxin further purified by thin-layer isoelectric focusing was pyrogenic and enhanced the susceptibility of rabbits to lethal endotoxin shock. Purified type C toxin appeared homogeneous when tested by Ouchterlony immunodiffusion and migrated as a single protein band in isoelectric focusing polyacrylamide gels (isoelectric point, 6.7) and sodium dodecyl sulfate-polyacrylamide gels (molecular weight, 13,200). The purified toxin was antigenically distinct from A and B SPE, and antisera raised against the purified toxin neutralized pyrogenic activity. The amino acid composition was determined.


Alveolar macrophage-lymphocyte rosette formation: failure of levamisole to alter activity. Levamisole, an anthelminthic agent with immunostimulatory properties, does not alter in vitro macrophage-lymphocyte rosette formation between sheep alveolar macrophages and autochthonous lymphocytes.


Intestinal stimulation of the serum antibody response against Escherichia coli O83 antigen in healthy adults. Ingestion of E. coli O83 bacteria preceded by intake of 2 g of NaHCO3 resulted in the bacteria appearing as a transient strain in the stool in 6 out of 11 healthy adult individuals. No rise in serum, urine or parotid fluid antibody levels against the crude O antigen from E. coli O83 bacteria could be detected using the enzyme-linked immunosorbent assay (ELISA) or the indirect haemagglutination (IHA) technique. In contrast, a serum antibody response was registered in four individuals with the ammonium sulphate precipitation (ASP) technique. The rise in antibody level was accompanied by an increase in relative average antibody avidity. Significantly lower levels of serum antibodies against the E. coli O83 and O6 antigens were recorded using the ASP technique as compared to those for O2, O4 and O75 antigens.


Effects of irradiation, anti-thymocyte serum and corticosteroids on PHA and LPS responsive cells of the mouse. Peripheral lymphocytes responsive to stimulation by phytohaemagglutinin (PHA) and bacterial lipopolysaccharide (LPS) in culture have been quantitated following treatment of mice with anti-thymocyte serum (ATS), total body irradiation or corticosteroids. The ATS reduced the number of PHA-responsive cells in both blood and spleen, and induced splenomegaly, but it had little deleterious effect on spleen-borne LPS-responsive cells. In contrast, the spleens of mice treated with hydrocortisone acetate were atrophied and the remaining cells had a reduced LPS response and an enhanced PHA response. Total body irradiation impaired both PHA and LPS responsiveness in the spleen. Recovery of PHA responsiveness after either irradiation or ATS treatment was prolonged and was dependent on the presence of an intact thymus; recovery of LPS responsiveness after corticosteroid treatment was more rapid and was thymus-independent.


Respiratory allergy in the dog: induction by the respiratory route and the effect of passive antibody. A technique for inducing hypersensitivity to prairie sage pollen (Artemisia gnopheles) in the dog was developed. The allergen induced skin reactivity in most dogs and respiratory hypersensitivity in 7 of the 17 animals tested. The respiratory hypersensitivity resembled naturally occurring respiratory allergies in both man and dog. The route of allergy induction resembles the natural route and it is felt that this system provides a useful model system for the study of respiratory allergies. Animals in which hypersensitivity was induced were used to investigate the role of passive 'blocking' antibody in respiratory allergy. It was observed that passive antibody will greatly inhibit the respiratory response to inspired allergen while completely inhibiting the cutaneous response. The results of these studies are discussed in relation to other studies.


Anti-T cell activity of niridazole in experimental autoimmune encephalomyelitis. The antischistosomal drug niridazole, known to selectively depress cell-mediated immune function, was assessed in experimental autoimmune encephalomyelitis (EAE) in mice. EAE results from an immune attack by activated T lymphocytes on the central nervous system. Niridazole given orally at a dose of 100 mg/kg body weight three times a week and starting either before or after immunization caused a significant suppression of signs and histological lesions of EAE, lasting up to ten weeks after cessation of treatment. There was no effect of niridazole on either release of macrophage migration inhibition factor in response to specific neural antigen, production of antibody, or on the nonspecific inflammatory reaction to adjuvant. Niridazole presumably acts by preventing release of lymphokines by activated T cells after contact with antigens.


Diagnosis of reaginic allergy with house dust, animal dander and pollen allergens in adult patients. V. A comparison between the enzyme-linked immunosorbent assay (ELISA), provocation tests, skin tests and RAST. An enzyme-linked immunosorbent assay (ELISA) employing allergen adsorbed onto the internal surface of a plastic tube, and alkaline phosphatase conjugated anti-IgE was used for the determination of specific IgE antibodies to various inhalant allergens in serum samples from 255 individuals with asthma and/or allergic rhinitis. A total of 541 analyses were carried out and the results were compared with those of provocation tests, skin tests and the RAST. It was found that negative ELISA values with high probability indicated nonallergy and very high ELISA values (class greater than or equal to 5) indicated allergy. However, the proportion of positive ELISA values which did not correspond to clinical allergy was high, as were the number of intermediate, inconclusive values (class 1-2). Although significant correlations between the ELISA values and provocation test, skin test or the RAST were obtained with some allergens, it was concluded that our version of the ELISA has not advantages over currently used methods for allergy diagnosis.


Estimation of basophil-bound IgE by quantitative immunofluorescence microscopy. By means of a previously developed basophil staining and fixation technique, it was possible to identify human basophilic granulocytes in leukocyte suspensions, which had been subjected to an immunofluorescence technique with anti-IgE. Using fluoresceinated anti-IgE, the fluorescence intensity of the basophils was measured by means of microfluorometry as a reflection of the IgE-load per cell. The reproducibility of this technique and the influence of the incubation time were studied. The mean fluorescence intensity of the basophil varied considerably in six donors, but the cells of two atopic patients showed the highest intensity. IgE was eluted from the cells at pH 2.5 and measured in the supernatant. A correlation was found between the amount of eluted IgE per basophil and the mean fluorescence intensity of the basophils. The number of IgE molecules per basophil was found to be in the range of 15,000--500,000.


Quantitation of basophil-bound IgE in atopic and nonatopic subjects. Basophil-bound IgE was measured by quantitative immunofluorescence microscopy in atopic subjects and in healthy controls. A correlation was found between IgE serum level and basophil-bound IgE. The basophils from the atopic patients, both from those with a low and those with an increased serum IgE, showed a significantly higher fluorescence intensity than the basophils from the respective controls. Our results indicate that both atopy and the IgE level of the serum determine the amount of basophil-bound IgE.


Regulation of the immune response in neonatal piglets by maternal antibody. The ability of maternal antibody to regulate the humoral immune response to sheep erythrocytes and the hapten-carrier conjugate trinitrophenylated sheep erythrocytes (TNP-SRBC) was investigated in neonatal piglets. It was found that in this system, passively acquired maternal antibody would completely inhibit the in vitro primary immune response to SRBC while leaving the response the TNP intact. Data suggest that maternal antibody is regulating the in vitro response at the B-cell level since T-cell helper function to SRBC must not have been inhibited in order for an anti-TNP response to have occurred to TNP-SRBC. The regulation of immune responses by maternal antibody is temporary and disappears before 3 months of age.


Restoration by levamisole of histamine-inhibited E rosette formation of T lymphocytes of patients with allergies. Histamine significantly inhibited the E rosette formation of T lymphocytes of patients with allergies in vitro, but had no effect on the E rosette formation of T lymphocytes of healthy subjects. This inhibitory effect was obtained by concentrations of 3.10(-4) down to 3.10(-7) M histamine and depended on the time of incubation. Levamisole an antianergic chemotherapeutic agent, could restore the histamine-inhibited E rosette formation. It is postulated that patients with allergies possess a subpopulation of T lymphocytes bearing histamine receptors and that the inhibitory effect of histamine on E rosette formation is medicated by intracellular cAMP.


Physiopathological inference by computer. A system has been programmed to allow model self-structuring to account for observations including both pathological evidence and symptomatological findings. The model modifies its structure in response to supplementary observations. The physiopathological mechanisms formalised by the model can be used for diagnostic purposes. Unknown diseases are diagnosed by direct inference of the relevant physiopathological mechanisms of the model or, if required, by automatic modification of the model that accounts for them.


[Formation of covalent linkages between the nucleic acid and protein constituents of E. coli MRE 600 ribosomes during gamma irradiation]. Gamma-irrdiation of E. coli MRE 600 ribosomes in aqueous suspensions leads to covalent linkages between the RNA and some ribosomal proteins. The presence of oxygen during the irradiation strongly inhibits this phenomenon. It appears clearly that only a few proteins are able to participate in these cross-linking reactions, which occur simultaneously in the two sub-units. The radiochemical yield was determined at several concentrations and was relatively low.


Radiovaccine of S. typhimurium cells.

Radiovaccine of S. typhimurium cells. Gamma-irradiation of S. typhimurium cells up to a dose of 500 krad significantly reduces their toxicity. However, the antigenicity of these cells is not altered, which suggests that these cells could be used as a vaccine. The protection offered by the irradiated cells is comparable to that of formalin-treated cells. The radio-vaccine, however, offers an additional advantage of significant detoxification of the endotoxin, thereby minimizing side effects. The lipopolysaccharide extracted from the irradiated S. typhimurium cells offered cross-protection against other Salmonella species tested.


Nuclear DNA synthesis in yeast and the effect of irradiation. The synthesis of DNA can be measured in yeast by following the uptake of 5-bromodeoxy-uridine-5'-triphosphate in a mutant that utilizes deoxythymidine-5'-monophosphate; approximately 60 per cent of the DNA is synthesized semi-conservatively before replication stops. Neither ultraviolet light (U.V.), nor ionizing radiation stimulates repair-type synthesis. Based on the ability to detect small amounts of synthesis, it appears that fewer than ten bases are synthesized per pyrimidine dimer removed.


A further examination of short-term corneal storage. Short-term corneal storage at a temperature of 4degrees C. was assessed with human cadaver eyes. Aqueous was replaced by air in one of each of 11 pairs of eyes, stored for periods of up to 96 hours post-mortem. The influence of air on the endothelial layer was measured in terms of corneal thickness, trypan blue staining, and scanning electron microscopy. Air-filled eyes developed less corneal edema over the storage period. No significant differences were found between the endothelia of test and control eyes. Degenerative changes in endothelium were documented photographically.


[Plastic surgery of lower lip defects (author's transl)]. A modification of the Hertig method for reconstruction of the lower lip is reported. The method is suitable for repair of lateral defects of the lower lip, and was performed in 10 patients. The procedure is technically simple to perform, and yeilds good functional and cosmetic results.


[The neurovascular island pedicle: basic considerations and its application in the face (author's transl)]. The island pedicle flap has in comparison with other skin flaps a number of important advantages which include elasticity, minimal shrinkage, absence of dog ears, success in irradiated areas and innecessity of a second stage procedure. On the head the most common donor areas for an island flap are postauricular, nasolabial, submental, and less cosmetically satisfying frontal and temporal regions. For large reconstrictions, however, only those pedicles which contain a branch of the superficial temporal or frontal arteries suffice. The major indications for an island pedicle flap include defects of the auricle, stenosis of the external auditory canal, through and through defects of the nose and paranasal region, in combination with other methods of skin grafting, and soft tissue loss and ectropion of the lower lid.


In vitro development of resistance to fosfomycin. Resistant colonies develop with an apparent high frequency in zones of inhibition around fosfomycin filter discs on nutrient agar. The resistance is due, primarily, to loss of the fosfomycin transport system. The resistant colony type usually observed in the inhibition zones seldom arise directly by mutation from a cell sown in the area of the zone of inhibition. Instead, small translucent colonies develop first in the inhibition zone. Within these small translucent colonies, mutational events occur which give rise to the normal resistant type colonies.


Papulacandins, a new family of antibiotics with antifungal activity, I. Fermentation, isolation, chemical and biological characterization of papulacandins A, B, C, D and E. Papulacandin, a new antibiotic complex, active against Candida albicans and several other yeasts, was isolated from a strain of Papularia sphaerosperma. The fermentation, isolation, physico-chemical properties and biological activity of the five structurally related papulacandins A, B, C, D and E are reported. Papulacandin B, the main component, was assigned the formula of C47H64O17.


Studies on aculeacin. I. Isolation and characterization of aculeacin A. Aculeacin A, a new antifungal antibiotic was isolated from the mycelial cake of Aspergillus aculeatus M-4214. The antibiotic is a white amorphous powder soluble in lower alcohols and hardly soluble in other organic solvents or water. Aculeacin A gave palmitic acid and five ninhydrin-positive products including theonine, hydroxyproline upon acid hydrolysis. The antibiotic showed a potent activity against molds and yeasts, but exhibited no antibacterial activity. Aculeacin A has relatively low toxicity in mice.


On the mode of action of a new antifungal antibiotic, aculeacin A: inhibition of cell wall synthesis in Saccharomyces cerevisiae. The mode of action of a new antifungal antibiotic, aculeacin A, was studied with the cells of Saccharomyces cerevisiae. In the presence of aculeacin A, the distinct decrease of viable cells was observed. The most of cells treated with aculeacin A lysed with releasing intracellular substances at the tips of their buds. This lysis was considered to be due to the inhibition of cell wall synthesis, because the incorporation of glucose into the cell wall glucan was significantly reduced. Aculeacin A also had a weak activity to burst the protoplasts of S. cerevisiae at a relatively high concentration.


In vitro susceptibility of cephalothin-resistant Enterobacteriaceae to cefoxitin and BL-S786. The in vitro antibacterial activity of two agents relatively resistant to beta-lactamases, BL-S786 and cefoxitin, was tested against 123 recent different clinical isolates of cephalothin-resistant Enterobacteriaceae. BL-S786 showed considerable activity against Escherichia coli and lesser activity against Klebsiella pneumoniae with, respectively, 68% and 41% inhibited at 32 microng/ml. Cefoxitin showed more activity in vitro against E. coli, K. pneumoniae, Serratia marcescens and Providencia stuartii. Cefoxitin appears to be a more promising agent for treating infections caused by cephalothin-resistant Enterobacteriaceae.


Regulation of amino acid transport in Escherichia coli by transcription termination factor rho. Amino acid transport rates and amino acid binding proteins were examined in a strain containing the rho-120 mutation (formerly SuA), which has been shown to lower the rho-dependent, ribonucleic acid-activated adenosine triphosphatase activity to 9% of the rho activity in the isogenic wild-type strain. Tryptophan and proline transport, which occur by membrane-bound systems, were not altered. On the other hand, arginine, histidine, leucine, isoleucine, and valine transport were variably increased by a factor of 1.4 to 5.0. Kinetics of leucine transport showed that the LIV (leucine, isoleucine, and valine)-I (binding protein-associated) transport system is increased 8.5-fold, whereas the LIV-II (membrane-bound) system is increased 1.5-fold in the rho mutant under leucine-limited growth conditions. The leucine binding protein is increased fourfold under the same growth conditions. The difference in leucine transport in these strains was greatest during leucine-limited growth; growth on complex media repressed both strains to the same transport activity. We propose that rho-dependent transcriptional termination is important for leucine-specific repression of branched-chain amino acid transport, although rho-independent regulation, presumably by a corepressor-aporepressor-type mechanism, must also occur.


Menaquinone biosynthesis: mutants of Escherichia coli K-12 requiring 2-succinylbenzoate. Two independent mutants of Escherichia coli K-12, selected for their inability to grow anaerobically with fumarate as the terminal electron acceptor, were shown to be deficient in menaquinone biosynthesis. In both cases, exogenously supplied 2-succinylbenzoate promoted normal anaerobic growth on a lactate plus fumarate medium. Anaerobic growth of the mutants on glucose minimal medium was impaired but could be restored to normal by adding either uracil or 2-succinylbenzoate. The addition of 2-succinylbenzoate (but not uracil) permitted the synthesis of menaquinone and demethylmenaquinone by both mutants. The menaquinone content of the parental strain grown on lactate plus fumarate was three times greater than observed after growth on glucose. Transduction studies with phage P1 showed that the two mutations are very closely linked and probably affect the same gene, menC, which is cotransducible with nalA (23%), glpT (51%), and purF (8 to 14%). The gene order nalA-nrdA-glpTA-menC-purF was indicated. The results were consistent with 2-succinylbenzoate being an intermediate in menaquinone biosynthesis and show that the gene designated menC (located at 48.65 min of the E. coli chromosome) is involved in the conversion of chorismate to 2-succinylbenzoate. It was also concluded that menaquinone is essential for electron transport to fumarate in E. coli.


Pathways of nucleotide biosynthesis in Mycoplasma mycoides subsp. mycoides. By measuring the specific activity of nucleotides isolated from ribonucleic acid after the incorporation of (14)C-labeled precursors under various conditions of growth, we have defined the major pathways of ribonucleotide synthesis in Mycoplasma mycoides subsp. mycoides. M. mycoides did not possess pathways for the de novo synthesis of nucleotides but was capable of interconversion of nucleotides. Thus, uracil provided the requirement for both pyrimidine ribonucleotides. Thymine is also required, suggesting that the methylation step is unavailable. No use was made of cytosine. Uridine was rapidly degraded to uracil. Cytidine competed effectively with uracil to provide most of the cytidine nucleotide and also provided an appreciable proportion of uridine nucleotide. In keeping with these results, there was a slow deamination of cytidine to uridine with further degradation to uracil in cultures of M. mycoides. Guanine was capable of meeting the full requirement of the organism for purine nucleotide, presumably by conversion of guanosine 5'-monophosphate to adenosine 5'-monophosphate via the intermediate inosine 5'-monophosphate. When available with guanine, adenine effectively gave a complete provision of adenine nucleotide, whereas hypoxanthine gave a partial provision. Neither adenine nor hypoxanthine was able to act as a precursor for the synthesis of guanine nucleotide. Exogenous guanosine, inosine, and adenosine underwent rapid cleavage to the corresponding bases and so show a pattern of utilization similar to that of the latter.


Partial purification of glycerophosphate acyltransferase from Escherichia coli. Glycerophosphate acyltransferase, a membrane-bound enzyme catalyzing the initial step of phospholipid biosynthesis in Escherichia coli, has been extracted with Triton X-100, a nonionic detergent, and purified 20- to 40-fold. This preparation is free from lysophosphatidate acyltransferase. Glycerophosphate acyltransferase is inactive in detergent extracts, but can be reconstituted by the addition of phospholipid. Under such conditions, the enzyme is associated with phospholipid. The sole product of the reaction with acyl coenzyme A as substrate is 1-acyl-sn-glycero-3-phosphate. Furthermore, the enzyme shows a marked preference for saturated fatty acyl conenzyme A, implying that this enzyme is responsible for the predominance of saturated moieties in position 1 of E. coli phospholipids. Acyltransferase from two mutants, plsA and plsB, was partially purified and characterized. Results support the view that plsB is a structural gene for the acyltransferase, but suggest that the plsA gene product is not directly involved in phospholipid biosynthesis.


Chloramphenicol-induced changes in the synthesis of ribosomal, transfer, and messenger ribonucleic acids in Escherichia coli B/r. The synthesis of ribosomal ribonucleic acid (rRNA), transfer RNA (tRNA) and messenger RNA (mRNA) was measured in Escherichia coli B/r after the addition of 100 mug of chloramphenicol (CAM) per ml to cultures growing either in one of three minimal media (succinate, glycerol, or glucose) or in one of the same three media supplemented with 20 amino acids. (i) During CAM treatment, rRNA and tRNA were synthesized in the same relative proportions (85:15) as during exponential growth. The faster accumulation of tRNA relative to rRNA in CAM was due to a decreased stability of rRNA that is synthesized in the presence of or immediately before the addition of CAM. (ii) CAM stimulated the synthesis of rRNA and tRNA two- to eightfold. The results fell into two groups; one group was from studies done in minimal media and the other was from amino acid-supplemented media. In each group the stimulation decreased with increasing growth rate of the culture during exponential growth before the addition of CAM; however, the stimulation in minimal media was lower than that in amino acid-supplemented media. (iii) CAM caused an increase in the proportion of rRNA and tRNA synthesis and a corresponding decrease in the proportion of mRNA synthesis. In minimal media, the residual proportion of mRNA synthesis after CAM treatment was 10 to 15% of total RNA synthesis; in amino acid-supplemented media this proportion was 0 to 10%. In either case, the residual proportion of mRNA synthesis was independent of the proportions observed during exponential growth in these media. (iv) The absolute rate of mRNA synthesis decreased severalfold with the addition of CAM; i.e., the rate of synthesis of rRNA and tRNA was increased at the expense of mRNA synthesis. (v) During exponential growth, the fraction of the instantaneous rate of total RNA synthesis that corresponds to mRNA is a function of both the growth rate and the presence or absence of amino acids in the growth medium: in the absence of amino acids, this fraction decreased with increasing growth rate; in the presence of amino acids, the fraction increased slightly with growth rate. These results are consistent with a regulation of rRNA and tRNA synthesis at the transcriptional level, e.g., with a CAM-induced increase in the affinity of RNA polymerase for the rRNA and tRNA promoters. The results also suggest the occurrence of a regulation of RNA polymerase enzyme activity, i.e., of an activation of RNA polymerase that is inactive during exponential growth. A distinction between these alternatives requires measurements of the rRNA chain growth rates during CAM treatment.


Rate of ribosomal ribonucleic acid chain elongation in Escherichia coli B/r during chloramphenicol treatment. In Escherichia coli B/r growing in glucose-amino acids medium, the radioactive labeling of 5S ribosomal ribonucleic acid (rRNA) and transfer RNA (tRNA) was measured after the simultaneous addition to the bacteria of chloramphenicol (CAM) (100 mug/ml), rifampin (200 mug/ml), and radioactive uracil. Accumulation of 5S rRNA ceased 85 s after the addition of rifampin, independent of the presence or absence of CAM; this indicates that CAM did not affect the rRNA chain growth rate. Together with previous measurements of the synthesis of rRNA and messenger RNA under these conditions, the results imply that CAM caused a redistribution of RNA polymerase which greatly favored stable RNA synthesis (77 to 97% of total functioning RNA polymerase engaged in synthesis of rRNA and tRNA). Further, it is inferred that RNA polymerase molecules were activated that were inactive during exponential growth. The labeling of tRNA observed under these conditions suggests the existence of clusters of tRNA genes at the 3' end of long transcripts that resemble the rRNA precursor in length and response to CAM and may be parts of rRNA transcripts.


Energy requirements for the transport of methylthio-beta-D-galactoside by Escherichia coli: measurement by microcalorimetry and by rates of oxygen consumption and carbon dioxide production. The energy cost for maintenance of gradients of methylthio-beta-d-galactoside in Escherichia coli was evaluated. Information was also obtained concerning the energy flow associated with gradient establishment under some circumstances. Energy flow was evaluated from transport-induced changes in the rate of heat evolution, oxygen consumption, and carbon dioxide production in metabolically active cells. Heats were measured with an isothermal calorimeter. Energy expenditure behavior was characterized by a transition that depended on the level of accumulation. The data for steady-state maintenance could be rationalized in terms of the Mitchell hypothesis, two models for influx and efflux, and a transition between them. At low levels of uptake, steady-state proton-methylthio-beta-d-galactoside (TMG) symport for influx and efflux occurred via a nonenergy-requiring exchange process. The only energy requirement was that necessary to pump back in any TMG exiting via a leakage pathway (model I). Above the transition, all influx occurred with proton symport, but all exit, leak and carrier mediated, occurred without proton symport (model II). The H(+)/TMG stoichiometric ratio computed for the region of model II applicability (carbon source present, high level of uptake) approached 1. This value agreed with that of other workers for downhill beta-galactoside flow, suggesting that the energy cost for both downhill and uphill flow was approximately the same. For low levels of uptake, initial establishment of the gradient was followed by a burst of metabolism that was much larger than that expected on the basis of the chemiosmotic hypothesis. In the absence of carbon source, the stimulation in respiration was sufficient to produce 13 times more protons than are apparently necessary to establish the gradient. The results indicate also that the nature of the biochemical process stimulated by TMG depends on its level of uptake. Insight into several aspects of the nature of these processes was provided through analysis of the heat, oxygen, and CO(2) data. The key factor controlling the transition in energy flow behavior is suggested to be rate of flux. The present data suggest that it occurs at a flux of approximately 120 nmol/min per mg of protein.


Determination of deoxyribonucleic acid replication time in exponentially growing Escherichia coli B/r. The time necessary to replicate the chromosome (C period) was measured in Escherichia coli B/r (ATCC 12407) and a low-thymine-requiring derivative of that strain. In the Thy- strain, C was measured as a function of growth rate and exogenous thymine concentration either from step-up or chloramphenicol experiments. In the Thy+ parental strain, C was measured only as a function of the growth rate and only by the chloramphenicol method. The C period was found to decrease with growth rate and, in the Thy- strain, the C period also decreased with increasing thymine concentration. It approached a value of approximately 37 min at high growth rates.


Genetics of sensitivity of Salmonella species to colicin M and bacteriophages T5, T1, and ES18. Nearly all of 62 strains of Salmonella paratyphi B were sensitive to colicin M and phage T5 but resistant to phages T1 and ES18 and to colicin B. All tested S. typhimurium strains were resistant to colicin M and phage T5, and many were sensitive to phage ES18. A rough S. typhimurium LT2 strain given the tonA region of Escherichia coli or S. paratyphi B became sensitive to colicin M and phage T5. We infer that the tonA allele of S. paratyphi B, like that of E. coli, determines an outer membrane protein that adsorbs T5 and colicin M but not phage ES18, whereas the S. typhimurium allele determines a protein able to adsorb only ES18. The partial T1 sensitivity of a rough LT2 strain with a tonA allele from E. coli or S. paratyphi B and also the tonB(+) phentotype of an E. coli B trp-tonB Delta mutant carrying an F' trp of LT2 origin showed that S. typhimurium LT2 has a tonB allele like that of E. coli with respect to determination of sensitivity to colicins and phage T1. Rough S. paratyphi B, although T5 sensitive, remained resistant to T1 even when given F' tonB(+) of E. coli origin. Classes of Salmonella mutants selected as resistant to colicin M included: T5-resistant mutants, probably tonA(-); mutants unchanged except for M resistance, perhaps tolerant; and Exb(+) mutants, producing a colicin inhibitor (presumably enterochelin). Some Exb(+) mutants were resistant to a bacteriocin inactive on E. coli but active on all tested S. paratyphi B and S. typhimurium strains (and on nearly all other tested Salmonella). A survey showed sensitivity to colicin M in several other species of Salmonella.


Independent regulation of transport and biosynthesis of arginine in Escherichia coli K-12. From an arginine auxotrophic strain, a mutant was isolated which is able to utilize d-arginine as a source of l-arginine and shows a high sensitivity to inhibition of growth by canavanine. Transport studies revealed a four- to five-fold increased uptake of arginine and ornithine in cells from the mutant strain. The kinetics of entry of arginine and ornithine evidenced elevated maximal influx values for the arginine- and ornithine-specific transport systems. A close parallel between arginine transport activity and arginine binding activity with one arginine-specific binding periplasmic protein in the mutant strongly suggests that such binding protein is a component of the arginine-specific permease. The affinity between arginine and the binder, isolated from the mutant cells, as well as the electrophoretic mobility of the protein, remain unchanged. The enhanced transport activity of arginine and ornithine with mutant cells is insensitive to repression by arginine or ornithine, whereas the biosynthesis of arginine-forming enzymes is normally repressible. When transport activity was examined in strains with mutations leading to derepression of arginine biosynthesis, the regulation of arginine transport was found to be normal. These studies support the conclusion that arginine transport and arginine biosynthesis, in Escherichia coli K-12, are not regulated in a concerted manner, although both systems may have components in common.


Evidence that specific and "general" control of ornithine carbamoyltransferase production occurs at the level of transcription in Saccharomyces cerevisiae. Ornithine carbamoyltransferase synthesis is subject to two major regulatory systems in Saccharomyces cerevisiae. One system is specific for the arginine biosynthetic enzymes, whereas the other appears to be general, acting on a variety of other amino acid pathways as well. We observed that the synthetic capacity for continued ornithine carbamoyltransferase synthesis had the same short half-life (ca. 5 to 7 min) whether repression of enzyme production was brought about by action of the specific or general control system. We present evidence suggesting that both control systems regulate accumulation or ornithine carbamoyltransferase-specific synthetic capacity, rather than modulating its expression.


Differential association of F' plasmid and R plasmid deoxyribonucleic acid with a rapidly sedimenting fraction of a Proteus mirabilis lysate. We have examined the association of an F' plasmid and an R plasmid in Proteus mirabilis with a rapidly sedimenting material that is generated by sodium dodecyl sulfate lysis and low speed centrifugation. Virtually all of the chromosomal deoxyribonucleic acid (DNA) and the F' plasmid DNA are associated with the rapidly sedimenting material after gentle lysis and centrifugation. A portion of R plasmid NR1 DNA (usually 5 to 25%) is not bound to the rapidly sedimenting material and is recovered in the supernatant fraction. This difference in binding is not related to the size of the plasmid DNA, since F' plasmids and R plasmids of different molecular weights showed the same behavior. R plasmid DNA labeled by a brief pulse of [(3)H]thymine is recovered in the supernatant fraction to a lower extent than the total R plasmid DNA. It would appear that R plasmid replication takes place in association with the rapidly sedimenting material. With prolongation of the [(3)H]thymine pulse, the [(3)H]thymine-labeled R plasmid DNA is recovered in the supernatant fraction with the same probability as the total R plasmid DNA. This finding indicates that a change in R plasmid attachment to the rapidly sedimenting material occurs some time after its replication. The differences observed in the replication of F' plasmids and R plasmids in P. mirabilis may be related to their different modes of association with the rapidly sedimenting material.


Biochemical and physiological studies of the yeast virus-like particle. A study was made of the virus-like particle (VLP) of Saccharomyces cerevisiae S7. This strain contains elevated amounts of P1 double-stranded ribonucleic acid (dsRNA) but no P2 dsRNA. The amount of dsRNA contained in cells grown on a fermentable carbon source (glucose) was compared with that in cells grown on a nonfermentable carbon source (ethanol). It was found that ethanol-grown cells contain higher levels of dsRNA than glucose-grown cells. In the former, the amount of dsRNA increased during the logarithmic phase of growth, whereas in the latter it increased during the transition from the logarithmic to the stationary phase. A method was devised to isolate VLPs from these cells by using CsCl gradients, and the yield was assessed by monitoring the recovery of dsRNA. Three proteins were found to be tightly associated with these particles. They have molecular weights of 75,000, 53,000, and 37,000. Together they account for almost all of the coding capacity of the P1 dsRNA that the VLP contains.


Effects of the hypocholesteremic agent trifluperidol on the sterol, steryl ester, and fatty acid metabolism of Saccharomyces cerevisiae. Trifluperidol (TFP), at a concentration of 100 muM, inhibited the 24-h growth of Saccharomyces cerevisiae by about 30%. Effects on lipid metabolism were investigated by monitoring the incorporation of [1-14C]sodium acetate into various lipid fractions after 4 and 24 h of growth in the presence of several concentrations of TFP. Although little effect was noted on the amount of free sterols, 24-h incorporation of label into steryl esters was increased two- to fourfold by 100 muM TFP. Major sterol components of the steryl ester fraction isolated from an untreated culture were zymosterol (48%) and ergosterol (24%), whereas from the TFP-treated culture delta8,24(28)-ergostadienol (66.6%) and delta8-ergostenol (14.7%) were most abundant. Free sterols present in the highest concentration in the untreated culture were ergosterol (78.2%) and lanosterol (13%); whereas delta8,22-ergostadienol (38.5%), delta8-ergostenol (35.4%), and delta8,24(28)-ergostadienol (25.4%) were the most abundant free sterols obtained from the TFP-treated culture. Thus, the major block in the sterol biosynthetic pathway in yeast appears to be delta8 leads to delta7 isomerization. In these same cultures the relative amounts of C12 and C14 acids isolated from both steryl ester and miscellaneous lipid fractions were increased more than threefold over controls.


Identification of polypeptides necessary for chemotaxis in Escherichia coli. Molecular cloning techniques were used to construct Escherichia coli-lambda hybrids that contained many of the genes necessary for flagellar rotation and chemotaxis. The properties of specific hybrids that carried the classical "cheA" and "cheB" loci were examined by genetic complementation and by measuring the capacity of the hybrids to direct the synthesis of specific polypeptides. The results of these tests with lambda hybrids and with a series of deletion mutations derived from the hybrids redefined the "cheA" and "cheB" regions. Six genes were resolved: cheA, cheW, cheX, cheB, cheY, and cheZ. They directed the synthesis of specific polypeptides with the following apparent molecular weights: cheA, 76,000 and 66,000; cheW, 12,000; cheX, 28,000; cheB, 38,000; cheY, 8,000; and cheZ, 24,000. The presence of another gene, cheM, was inferred from the protein synthesis experiments. The cheM gene directed the synthesis of polypeptides with apparent molecular weights of 63,000, 61,000, and 60,000. The synthesis of all of these polypeptides is regulated by the same mechanisms that regulate the synthesis of flagellar-related structural components.


Scanning electron microscopy of Treponema pallidum (Nichols strain) attached to cultured mammalian cells. This paper describes the attachment of Treponema pallidum (Nichols strain) to cultured mammalian cells as a visualized by scanning electron microscopy. Treponemes were incubated for 3 hr with cultured cells derived from normal rabbit testes or human skin epithelium, then fixed, processed with critical-point drying, and examined with a Cambridge Mark 2A scanning electron microscope. Large numbers of treponemes became attached to the cultured cells without altering the morphological integrity of the cultured cells. Attachment appeared to involve a very close physical proximity of treponemes to the cultured cells; at the site of attachment, no changes such as swelling or indentation of the cultured cell surface were observed. The addition of ruthenium red to the fixatives produced a treponemal-associated surface precipitate. This material, which is probably mucopolysaccharide and/or phospholipid, may be important in protecting the organisms against host defense mechanisms; in addition, it may be involved in the serological unresponsiveness of freshly prepared suspensions of T. pallidum.


Inhibition of Histoplasma capsulatum ribonucleic acid polymerases by homologous and heterologous ribonucleic acid. The ribonucleic acid (RNA) polymerases from the yeast phase of Histoplasma capsulatum are differentially sensitive to RNA isolated from the yeast and mycelial phases of this fungus and from Escherichia coli. Low-molecular-weight RNA from H. capsulatum was the most effective inhibitor.


Deoxyribonucleic acid strand breaks during freeze-drying and their repair in Escherichia coli. Freeze-drying of Escherichia coli cells caused strand breaks of deoxyribonucleic acid (DNA) in both radiation-sensitive and -resistant strains. However, in the radiation-resistant strain E. coli B/r the damaged DNA was repaired after rehydration, whereas in the radiation-sensitive strain E. coli Bs-1 the damaged DNA was not repaired and the DNA was degraded. Repeated freeze-drying did not break the damaged DNA into smaller pieces.


Characterization of plasmids in a sucrose-fermenting strain of Escherichia coli. A multiply drug-resistant strain of Escherichia coli isolated from a patient in Bangladesh was shown to carry four types of plasmids based on size differences. One type carries a gene or genes for sucrose fermentation.


Methanococcus vannielii: culture and effects of selenium and tungsten on growth. The reisolation, culture, and method of preservation of the methane-producing organism Methanococcus vannielii are described. Growth of the organism on formate is markedly stimulated by selenium and tungsten.


Replicative deoxyribonucleic acid synthesis in isolated mitochondria from Saccharomyces cerevisiae. The characteristics of a system for the in vitro synthesis of mitochondrial deoxyribonucleic acid (mtDNA) in mitochondria isolated from Saccharomyces cerevisiae are described. In this system the exclusive product of the reaction is mtDNA. Under optimal conditions the initial rate of synthesis is close to the calculated in vivo rate; the rate is approximately linear for 20 min but then decreases gradually with time. DNA synthesis proceeds for at least 60 min and the de novo synthesis of an amount of mtDNA equivalent to 15% of the mtDNA initially present is achieved. The rate and extent of synthesis observed with mitochondria isolated from grande and petite (rho(-)) strains were similar. The mode of DNA synthesis is semiconservative; after density labeling with 5-bromodeoxyuridine triphosphate, in vitro, the majority of labeled DNA fragments of duplex molecular weight, 6 x 10(6), are of a density close to that calculated for hybrid yeast mtDNA. The density label is incorporated into one strand of the duplex molecules. These properties indicate that the synthesis resembles replicative rather than repair synthesis. This system therefore provides a convenient method for the study of mtDNA synthesis in S. cerevisiae. The observation that mtDNA synthesis is semiconservative in vitro suggests that the dispersive mode of synthesis observed in S. cerevisiae in vivo labeling studies is the result of some other process, possibly a high recombination rate.


Structural specificity of the allosteric inhibitor of phosphoenolpyruvate carboxylase of Escherichia coli. The structural specificity of the allosteric inhibitor of phosphoenolpyruvate carboxylas [EC 4.1.1.31] of Escherichia coli W was investigated using native enzyme and photooxidized enzyme which was desensitized to L-aspartate. Inhibitory activity was expressed in terms of the concentration of the compound required for 50% inhibition (I0.5). For the native enzyme, L-aspartate and L-malate were the strongest inhibitors with I0.5 values of about 0.10-0.15 mM among about 20 componds tested. For the photooxidized enzyme, oxaloacetate and L-malate were relatively strong inhibitors wiht I0.5 values of about 11-16 mM. The results obtained suggest that the inhibition of the native enzyme mainly reflects allosteric inhibition.


Effect of testosterone on the amount of serous-like granules in convoluted tubular cells of mouse submandibular glands. The effect of testosterone on the amount of granules present in convoluted tubular cells of the submadibular glands of mice was studied by the following two methods; 1) an immunochemical method using antiserum specific to the granular components, and 2) a histographic method. The results obtained by these two methods were in agreement. The amounts of the granules in normal female and castrated male mice were one-tenth to one-twentieth of that in normal male mice. When male mice were castrated, the amount of granules decreased, reaching a minimum 20 days after the aperation the injection of the male hormone, testosterone, into castrated male mice caused an increase in the amount of granules; this increase reached a maximum 15 days after the injection. The increase of granules caused by testosterone injection was almost completely prevented by inhibitors of protein synthesis, actinomycin D and puromycin. This suggests that protein synthesis was indispensable to the increase in the amount of granules. In male mice, the injection of female hormones scarcely affected the amount of granules. Kinetic analysis of the decrease and increase of granules on castration and testosterone injection suggested that the male hormone stimulated granule synthesis, but it hardly influenced the loss of granules.


Use of 3H and 14C double-labeled glucose to assess in vivo pathways of amino acid biosynthesis in Escherichia coli. 3H and 14C tracing data concerning amino acid biosynthetic pathways in Escherichia coli K12 are presented. Thirteen acidic and neutral amino acids were isolated from protein hydrolysates of wild type E. coli K12 grown aerobically or anaerobically in the presence of [U-14C]glucose together with [1-3H]glucose, [3-3H]glucose, [4-3H]glucose, or [6-3H]glucose. The observed 3H/14C counts of the amino acids were compared with the ratios expected on the basis of the input substrate specific activities and present understanding of biosynthetic pathways. For nine amino acids, serine, valine, leucine, threonine, isoleucine, glycine, glutamate, proline, and phenylalanine, the agreement between anticipated and observed specific activities was satisfactory. For the remaining four, methionine, alanine, aspartate, and (in cells labeled with [3-3H]glucose) tyrosine, the anticipated and observed specific activities differed markedly. For alanine, aspartate, and tyrosine, the differences are probably due to exchange of tritium in the course of biosynthesis; for methionine, it may be that there is a principle source of the methyl group other than carbon 3 of serine.


Negative interactions between amino acid and methylamine/ammonia transport systems of Saccharomyces cerevisiae. The transport of methylamine (methylammonium ion) and ammonia (ammonium ion) is accomplished in Saccharomyces cerevisiae by means of a specific active transport system. L-Amino acids are noncompetitive inhibitors of methylamine transport. This inhibition is relieved or eliminated in mutant strains that have a reduced ability to transport amino acids. The inhibition of methylamine transport occurs immediately upon the addition of amino acids to the assay system and persists until the external amino acid pool is depleted. The degree of inhibition observed is a direct function of the rate of amino acid transport. Both methylamine and ammonia are capable of inhibiting amino acid transport. The inhibition of amino acid transport is eliminated in mutant strains that cannot transport methylamine and ammonia.


Amino acid sequence of Escherichia coli biotin carboxyl carrier protein (9100). The amino acid sequence of a proteolytic fragment of Escherichia coli biotin carboxyl carrier protein was determined from the structures of overlapping tryptic, thermolytic, and staphylococcal protease peptides together with automated sequenator analyses on the intact protein. The fragment, 82 residues in length, contains the single residue of biocytin of the protein. The relationship of the Mr = 9100 fragment to the native Mr = 22,500 subunit is discussed.


Limited pepsin digestion of human plasma albumin. Limited pepsin digestion of human plasma albumin at pH 3.5 and 0 degrees in the presence of octanoate caused cleavage at residue 307 of the albumin molecule to yield two fragments. Thw two fragments corresponding to the NH2- and the COOH-terminal halves of the molecule were isolated in yields of about 15%. The COOH-terminal fragment is a mixture in which about 85% of the molecules had an additional cleavage at residue 422 of the albumin molecule. The COOH-terminal fragment with the additional cleavage at residue 422 contains two peptides which are linked by a disulfide bridge at residues 391 and 437 of the albumin molecule. Both the NH2- and the COOH-terminal fragment of human albumin showed no detectable binding of octanoate anions, that is, less than 1/170 of the binding constant of the primary site of human albumin. These findings differ from earlier observations on limited pepsin digestion of bovine plasma albumin where the corresponding COOH-terminal fragment had the octanoate-binding activity, about 1/8 of the  primary binding constant of bovine albumin, while the NH2-terminal fragment did not. The COOH-terminal fragment of bovine albumin did not have cleavage at residue 422 as in the corresponding fragment of human albumin. However, it is not clear that the loss of octanoate-binding activity of fragment C of human albumin is a direct consequence of the cleavage at residue 422.


Studies of the mechanism of tunicamycin in hibition of IgA and IgE secretion by plasma cells. Tunicamycin, an antibiotic which blocks the formation of N-acetylglucosamine-lipid intermediates, thereby preventing glycosylation of glycoproteins, inhibits the secretion of IgA and IgE by MOPC 315 mouse plasma cells and IR162 rat plasma cells, respectively. At 0.5 microng of tunicamycin per ml, D-[14C]glucosamine incorporation into newly synthesized immunoglobulin was inhibited greater than 90% while the overall rate of protein synthesized was much less inhibited (40% in the case of MOPC 315 cells and 13% in the case of IR162 cells). This dose of tunicamycin produced an 85% inhibition of IgA secretion by the MOPC 315 cells and a complete inhibition of intact IgE secretion by the IR162 plasma cells. In contrast, tunicamycin had little effect on the secretion of normally nonglycosylated lambda light chains or on cell-free protein synthesis, demonstrating that tunicamycin is not a general inhibitor of protein synthesis or a non-specific inhibitor of protein secretion. No enhancement of intracellular degradation of nonglycosylated immunoglobulin could be demonstrated. Electron microscopy of tunicamycin-treated MOPC 315 cells revealed marked dilatations of the rough endoplasmic reticulum, and direct immunofluorescence indicated that the dilated rought endoplasmic reticulum contained IgA. These data indicate that glycosylation of newly synthesized IgA and IgE may be necessary for normal secretion to occur.


Subunit structure of external invertase from Saccharomyces cerevisiae. Because 50% of the mass of the external invertase of Saccharomyces cerevisiae consists of carbohydrate, it has been extremely difficult to obtain an accurate molecular weight of this enzyme by centrifugal or electrophoretic techniques. However, on removing almost all of the oligosaccharide chains of this enzyme with the endo-beta-N-acetyl-glucosaminidase H from Streptomyces plicatus, it has been possible to show that carbohydrate-free invertase is composed of two 60,000-dalton subunits. Terminal sequence analysis with carboxypeptidases A, B, and Y provided strong evidence that the subunits are identical.


19F nuclear magnetic resonance of 5-fluorouridine-substituted tRNA1Val from Escherichia coli. The 19F NMR spectrum of Escherichia coli tRNA1Val in which [5-19F]uridine replaces 93% of all uridine and uridine-derived residues has been examined at 93.6 and 235 MHz. The resolution of 11 peaks and visibility of two additional shoulders at either frequency for the 14 FUra residues in the molecule attests to the excellence of 19F as a probe for the structure of tRNA1Val in solution. No significant gain in resolution was attained at the higher frequency. A comparison of the relative areas in the different regions of the 19F spectrum of mixed [FUra]tRNAs with that of [FUra]tRNA1Val suggests that the three single resonances at lowest field in the region 86.5 to 88.5 ppm upfield from trifluoroacetate correspond to the three invariant bases which form tertiary hydrogen bonds in all tRNAs, namely, 8 (U or s4U), 54 (T), and 55 (phi) in unsubstituted tRNAs.


Failure of orally administered hydroxychloroquine sulphate to prevent venous thromboembolism following elective hip operations. In a double-blind, randomized trial of orally administered hydroxychloroquine sulphate in the prevention of venous thromboembolism after elective surgery on the hip, the drug or a placebo was given to fifty consecutive patients. Therapy was commenced on the day before the operation and continued for fourteen days. The diagnosis of deep venous thrombosis was made by daily thermographic scanning of the legs and confirmed by phlebography. The diagnosis of pulmonary embolism was made by perfusion lung scanning. No significant difference in the incidence of thromboembolism was found between treated and control groups. The results provide evidence that substances which reduce the incidence of thromboembolism in general surgery may not be effective in operations on the hip.


Skeletal cryptococcosis.

Skeletal cryptococcosis. We reviewed the published reports of skeletal cryptococcosis and added three cases to the fifty-six in the literature. Eight of the patients in the reported cases probably did not have primary skeletal cryptococcosis. The potential toxicity of antifungal drugs in current use and the apparent effectiveness of surgical treatment for patients who only have a single focus of infection in bone, without involvement of other tissues, should be noted. The association of cryptococcosis with other diseases and the difficulty in differentiating purely skeletal involvement from more extensive disease are emphasized.


Treatment of unicameral bone cysts by subtotal resection without grafts. Twenty-one patients were treated operatively for unicameral bone cysts by subtotal resection without any form of bone graft, and all but two patients had satisfactory, prompt healing. The rate of recurrence was 9%. Five patients were noted to have humeral shortening prior to any surgery, and in them the changes in the epiphyseal cartilage were noted preoperatively. Pathological fractures were thought to be the cause of the shortening in those cases.


Chromatography of biogenic amines. I. Generally applicable separation and detection methods. This first part of the review on "Chromatography of Biogenic Amines" is devoted to the description of generally applicable separation and detection methods. Gas chromatographic and gas chromatographic-mass spectrometric methods, and applications of chromatographic methods to specific amines or groups of related amines and their metabolites, will be covered in Part II. Trends in the development of separation methods (paper and thin-layer chromatography, paper and thin-layer electrophoresis and ion-exchange methods) are described, using mostly aliphatic amines as examples as they do not exhibit features that permit their specific determination. Reagents suggested for the formation of coloured and fluorescent derivatives of amines are reviewed and their applications are described. Within the limitation of the reviewed and their applications are described. Within the limitation of the mostly inadequate information that is available, the relative usefulness of the different derivative-forming reactions are compared.


Circulating immune complexes detected by 125I-Clq deviation test in sera of cancer patients. The presence of circulating immune complexes in freshly drawn sera of patients with various forms of malignancies was detected by the 125I-Clq deviation test of Sobel et al. More than 50% of the 459 cancer sera showed a high inhibition of 125I-Clq uptake by sensitized sheep erythrocytes when compared with sera of 50 healthy laboratory personnel. The levels were compared with levels of total hemolytic complement and immunochemical determinations of Cl1 and C3. A correlation between high levels of circulating immune complexes and low levels of Clq was suggested. These immune complexes were separated by sucrose density gradient ultracentrifugation at low pH and were found to be heavier than 19S. Fluctuation of levels of immune complexes was evident when serial samples from the same patient were tested. Decrease of levels of immune complexes and a concomitant increase of Clq were detected after Calmette-Gueérin bacillus and autologous tumor cell treatment in some melanoma patients.


Four years experience with dura mater cardiac valves. The clinical use of homologous dura mater cardiac valves was begun in January 1971. Between January 1971 and May 1975, 751 patients received 849 dura mater valves: 428 mitral, 365 aortic, 52 tricuspid and 4 pulmonary. The hospital mortality observed in this series was 13.6% and late mortality was 2.5%. The main causes of death were low-output syndrome in the immediate post-operative period or cardiac failure in the late post-operative period, due to myocardial impairment. Paravalvular leaks and errors in the manufacture of the valve were the main causes of regurgitation both in the immediate and late post-operative period. The incidence of thromboembolism, bacterial and fungal endocarditis was: 0.79%, 0.39%, 0.53% respectively. The results obtained with dura mater valve in a period of four years are satisfactory from the clinical and hemodynamic points of view.


Sarcoidosis: histopathological definition and clinical diagnosis. Sarcoidosis is best defined in histopathological terms as 'a disease characterised by the presence in all of several affected organs and tissues of non-caseating epithelioid-cell granulomas, proceeding either to resolution or to conversion into hyaline connective tissue'. Although the defining characteristics are thus histopathological, diagnosis during life depends largely upon clinical, radiological, and immunological findings. The amount of support required from histology varies greatly from case to case.  Though histology from one site cannot in itself establish the diagnosis of sarcoidosis, a generalised disease, detailed histological study of biopsy tissue makes an important and often essential contribution. In many instances, complete lack of necrosis, an intact reticulin pattern, and failure to demonstrate infective agents permit an unequivocal statement of compatibility with this diagnosis; however, a compatible clinical picture and absence of evidence of known causes of local granulomatous reactions or of other generalised granulomatous diseases are required for definitive diagnosis. In some, the histological pattern deviates in some particular from the accepted 'typical' pattern; there may be a little necrosis, the follicular pattern of the granuloma may be less than perfect, and exclusion of known infective agents can never be absolute. In such instances, subsequent surveillance, including possible response to treatment, may show a clinical course justifying a diagnosis of sarcoidosis, and necropsy may establish it; but it must be recognised that in a few cases, particularly those in which the clinical evidence of disease is confined to one organ, diagnosis is likely to remain in doubt for long periods. Reports on the histology of the Kveim test should be made without knowledge of clinical findings and in terms of the presence and quality of granulomatous response. A granulomatous reaction to a validated test suspension makes a contribution to diagnosis similar to the finding of granulomas in an additional organ or tissue.


Routine laboratory assessment of postoperative chest infection: a prospective study. Postoperative chest infection was studied prospectively in 73 patients in order to evaluate standard laboratory methods of sputum examination and to relate the results to the patients' clinical state and to antibiotic therapy. When a culture medium selective for haemophilus was used in addition to unselective media, homogenisation of the specimen gave no advantage. Laboratory and clinical findings usually corresponded well. Profuse growths of Streptococcus pneumoniae or Haemophilus influenzae were clearly associated with clinical evidence of chest infection but other Gramnegative bacilli and Staphylococcus aureus much less so. Coliforms were more prominent after antibiotic therapy.


Further studies on the reliability of the bacitracin inhibition test for the presumptive identification of Lancefield group A streptococci. The reliability of the bacitracin inhibition test to differentiate between 125 Lancefield group A and 122 non-group A beta-haemolytic streptococci was studied. Bacitracin discs containing 0-02, 0-04, or 0-1 international units and the conditions recommended by both the Association of Clinical Pathologists and the Federal Drug Administration for routine sensitivity testing were used. The results suggest that the presence or absence of a zone of inhibition around a 0-04 unit disc can be used routinely for the presumptive identification of group A streptococci and that a specific zone size can be used for reading the test only with a 0-1 unit disc.


Experimental transient bacteraemias in human subjects with varying degrees of plaque accumulation and gingival inflammation. Ninety-six subjects were assigned to one of four groups according to severity of gingival inflammation and bacterial plaque accumulation on the teeth. Following a standardized toothbrushing procedure, blood specimens from a vein in the antecubital fossa were cultured under aerobic and stringent anaerobic conditions. The percentage of positive cultures increased significantly with increasing severity of gingival inflammation, as did the number of species of organisms isolated. Thirty different microbial species indigenous to the oral cavity, including many strict anaerobes, were recovered. The study has implications for standards of oral health which might be considered necessary in patients with congenital or acquired endocardial defects or cardiovascular prostheses.


Survey of patented anti-stuttering devices. Various types of devices have been patented to alleviate stuttering. Some prevent certain physical actions, such as clamping of the teeth, improper movement of the tounge and improper breathing. Others strengthen or incapacitate certain muscles. The devices and their alleged action on the body are described. United States as well as foreign patents are included. No attempt has been made to evaluate said devices


Luteinizing hormone and testosterone concentrations in plasma of bull calves treated with gonadotropin releasing hormone. Twelve bull calves, 2 to 24 days of age, were assigned to two groups of six calves and administered a single 50 microng intramuscular injection of gonadotropin releasing hormone. Bull calves in group 1 were 2 to 5 days of age (mean 3.0 days), and bull calves in group 2 were 10 to 24 days of age (mean 17.1 days). Blood plasma for radioimmunoassay of luteinizing hormone and testosterone was collected at .5-h intervals for 3-h and at 4- and 6-h following treatment. With increasing age, preinjection luteinizing hormone concentrations in plasma decreased while preinjection testosterone concentrations increased. Mean preinjection luteinizing hormone concentrations for group 1 (1.01 +/- .07 ng/ml; mean +/- standard error) were higher than for group 2 (.61 +/- .12 ng/ml). Preinjection luteinizing hormone and testosterone concentrations were correlated--.63. Following treatment, luteinizing hormone increased with mean peak concentrations of 7.28 +/- .74 and 6.95 +/- 1.79 ng/ml for groups 1 and 2. Peak testosterone response following gonadotropin releasing hormone was higher for group 2 than 1 (1077 +/- 253 versus 436 +/- 116 pg/ml).


Labile protein reserves and protein turnover. The concept of a labile protein reserve is based on the relatively slow establishment of a new equilibrium in the rate of nitrogen excretion after an abrupt change in dietary supply. The evidence reviewed shows that a majority of this nitrogen is derived from or deposited in skeletal muscle proteins. The rates of synthesis and degradation of total body protein are rapid in large animals (man and swine) and are correlated with heat production. The rate of protein synthesis in skeletal muscle greatly exceeds the rate of growth and is sensitive to nutritional status. The rate exceeds the rate of degradation in response to the ingestion of an adequate diet so that tissue proteins are accumulated, but it decreases below the rate of degradation under conditions of deprivation. In this latter state, proteins of skeletal muscle supply amino acids for energy or for the synthesis of other more essential proteins, e.g., milk proteins during lactation. Thus, we conclude that the labile protein reserve is a product of the normal, dynamic metabolism of protein.


Colostral cell-mediated immunity and the concept of a common secretory immune system. Historically colostrum and milk have been thought to confer immunity on the neonate only by virtue of their immunoglobulin content. Recently we have observed that colostrum also contains viable T lymphocytes capable of expressing cell-mediated immunity in vitro and have employed techniques of lymphocyte culture to elucidate the local nature of mammary tissue immunity at the T-cell level. The results indicate that the activity of colostral lymphocytes appears not to represent the total immunological experience of the mother but that they may contain reactive clones beneficial for the suckling. Colostral immunity appears to depend upon sensitizing events within the intestine and respiratory tract, followed by the migration of lymphoid precursors to the breast, suggesting a relationship between the expression of immunity at various secretory surfaces.


Human relations with dental personnel.

Human relations with dental personnel. This review of psychological notions and outline of experiential training can be employed as a sensitizing device to heighten dental care providers' awareness of the psychosocial aspects of dentistry. Additionally, the objective of further developing personal effectiveness is based on the premises that (1) the value of techincal skills can be enhanced by a clear and empathic appreciation for the consumer and (2) the care provider's command of his own interpersonal effectiveness can be facilitated by an appreciation for his current skill level.


Pulmonary oedema associated with hydrocarbon inhalation. A patient with gross pulmonary oedema secondary to inhalation of paint fumes is described. Treatment with mechanical ventilation and positive end expiratory pressure was required.


Technique for the fabrication of a cast post and core with nonprecious metal. A technique for the construction of a cast post and core with a nonprecious metal is described. The technique is a practical and inexpensive approach to the construction of this type of restoration.


Effects of design on stress distribution of intracoronal gold restorations. Eight intracoronal and extracoronal designs for gold restorations with different tapers to the lateral walls were investigated to determine the most efficient design in distributing occlusal stresses. It was found that the occulusal wall of an inlay cavity with a 7 degree taper and no bevel resulted in a better stress distribution than a cavity preparation with a greater taper or a long bevel. It was shown further that a wide inlay preparation resulted in less stress if the cusps were protected by gold.


Malignant angioendothelioma of the face. A case of malignant angioendothelioma of the face is presented. A combination of conventional wide excision, chemosurgery (Mohs' technique), and plastic reconstruction proved successful. To our knowledge, this is the first case of a facial lesion of this type that has been cured by surgery.