[Mechanism of action of catecholamines on sodium transport in sections of rat renal cortex]. Stimulation of renal beta-adrenoreceptors increased passive accumulation of sodium and water contents in cells of renal sections incubated in non-oxygenated medium without potassium and glucose but had no effect on the passive loss of potassiuna. During incibation of sodium loaded sections in oxygenated medium with potassium and glucose, stimulation of beta-adrenoreceptors increased excertion of sodium from the sections, and accumulation of potassium, which was followed by reducing of intracellular water. Activation of beta-adrenoreceptors during action of catecholamines seems to elicit an increased passive inflow of sodium into the cells of renal channels and to activate the ionic pump pumping away sodium in exchange for potassium.


[Excitatory postsynaptic potentials in the lumbar motor neurons of frogs induced by stimulation of muscle and cutaneous nerves]. The postsynaptic effects evoked in lumbar motoneurons by stimulation of different muscle and cutaneous nerves of hindlimbs were studied by means of intracellular recording in the frog isolated spinal cord. The data obtained confirm presence of monosynaptic connections between primary afferents and spinal motoneurons. Monosynaptic EPSPs were shown to be due to low threshold muscle afferent volleys in homonymous nerves and did not generate spike discharges. The mean amplitude of monosynaptic EPSPs was 1.1 +/- 0.12 mV, time-to-peak 1.76 +/- 0.16 msec, time constant of decay from 6.0 to 15.0 msec. EPSPs with no synaptic delay were recorded in some motoneurons which suggest existence of an electrical mechanism of transmission.


Changes in radiosensitivity induced by cyclic nucleotides and chemical radioprotection. Cyclic AMP has a radioprotective effect and its aministration results in a significant increase in LD50/30 values in Chinese hamsters. The efficiency of these radioprotective effects is comparable to that of such radioprotective compounds as AET and cystamine + mexamine. Cyclic GMP is responsible for significant radiosensitizing effects. Changes in radiosensitivity after administration of cyclic nucleotides are both immediate and delayed and correlate closely with dose and time of administration.


hCG suppression of LH receptors and responsiveness of testicular tissue to hCG. A single injection of 75 IU of human chorionic gonadotropin (hCG) into adult male rats caused a dramatic reduction in the concentration of membrane receptors for luteinizing hormone (LH) in the testis. The mean receptor level reached a nadir which was 5--10% of that in the control testes, 3 days after the injection, after which it gradually returned toward normal. This cannot be due to increased competition caused by the injected hCG since no decrease was observed at a time when the circulating levels of hCG were at a maximum (2--24 h after injection). Furthermore, at a time when receptor levels had been maximally reduced, circulating hCG was at or below the level of detection. Reduction in the number of LH binding sites in the testis was associated with a decreased responsiveness of the testicular tissue to hCG as measured by hCG-stimulated testosterone production in vitro. This inhibitory effect of large quantities of LH on its own receptor is suggested as a possible explantation for the previously observed low concentrations of LH receptor in the testis of the testicular feminized male (tfm) rat. This syndrome is characterized by high endogenous levels of plasma LH (Sherins et al., 1971).


Pancreatic perinuclear inclusions in diabetes mellitus and other diseases. Unusual perinuclear inclusions in pancreatic duct cells were observed by electron microscopy in 23 diabetic pancreases, in nine pancreases with islet hyperplasia, and in 10 of 27 pancreases without islet pathology. The origin and significance of the perinuclear inclusions could not be determined, but it is suggested that they may be of viral origin or may represent a cellular response to an unknown stimulus.


[Antibodies against the cytomegalic virus and Toxoplasma gondii in a sample of the Monrovia population]. Cytomegalovirus and Toxoplasma gondii antibodies were titered in 133 serum specimens from students, physicians and technical staff of Monrovia hospital. The findings obtained show that both infections are widely spread: Cytomegalovirus antibody was detected in 81%, and Toxoplasma antibody in 70% of tested sera. No significative differences were observed among sera from different tribes and birth places.


Isolation and characterization of MMS-sensitive mutants of Saccharomyces cerevisiae. We have isolated mutants sensitive to methyl methanesulfonate (MMS) in Saccharomyces cerevisiae. Alleles of rad1, rad4, rad52, rad55 and rad57 were found amoung these mms mutants. Twenty-nine of the mms mutants which complement the existing radiation-sensitive (rad and rev) mutants belong to 22 new complementation groups. Mutants from five complementation groups are sensitive only to MMS. Mutants of 11 complementation groups are sensitive to UV or X rays in addition to MMS, mutants of six complementation groups are sensitive to all three agents. The cross-sensitivities of these mms mutants to UV and X rays are discussed in terms of their possible involvement in DNA repair. Sporulation is reduced or absent in homozygous diploids of mms mutants from nine complementation groups.


Enzymatic activity of Ammon's horn in the ontogenetic development of the rat. Studies were performed on the activity of several enzymes in Ammon's horn of rat during an individual postembryonal development. For the studies rats of Wistar strain were used that were killed on the 1st, 3rd, 8th, 17th, 40th and 60th day after birth. In the experiment the brains were removed, cut, and the activity of dehydrogenases, phosphatases and esterases was revealed. During the performed studies some considerable differences were shown in the activity of several dehydrogenases, in each particular field of Ammon's horn, undergoing changes in the periods of ontogenetic development under study. Furthermore, some distinct differences in the phosphatases and esterases activity were revealed in each area of the Ammon's horn. Attention was drawn to a comparatively late histo-enzymatic maturation of Ammon's horn in comparison with other structures of the limbic system.


Enzymatic activity of hydrolases in the spinal cord of rat after an acute and subacute calomel introxication. Studies have been performed on changes in the activity of hydrolytic enzymes in spinal cord following a toxic action of calomel. With the use of a gastric cannule, the rats were being administered mercurous chloride. The first group were given Hg2Cl2 in a 0-05 g. dose for four days whereas the second experimental group received a 0-012 g. for ten days. As a result of the studies, both in an acute and subacute calomel intoxication, an increase in TTP-ase and NsE activity in spinal cord as well as a decrease in ATP-ase, AChE and AcP activity were found. It was also shown that mercurous chloride intoxication exerts of influence on AIP and BuTJ activity. In the discussion an attempt was made to explain some of the observed phenomena.


Phosphatases and esterases activity in the brain following an acute sublimate intoxication. Experiment studies were performed on rats that were administered mercury chloride sublimate with a special gastric cannule in a single 6 mg dose for four consecutive days. As a result of the investigations some changes in the phosphates and esterases activity were revealed. The diminution of AcP, AIP, ATP-ase and AChE activity as well as in the increase in TPP-ase activity in the neurocytes, and also the appearance on NsE activity in many oligodendrocytes was observed. The fall in ATP-ase activity was, above all, observable in cerebral and cerebellar capillaries, which is, in the authors opinion, a manifestation of enzymatic damage to the blood-brain barrier due to a toxic action of mercuric chloride. In the discussion attention was drawn to differences in the degree of enzymatic activity between a mercuric chloride intoxication and that with mercurous chloride, as well as attempt was made to explain the pathogenetic mechanism of this phenomenon. Furthermore, notice was brought to the fact that in the course of sublimate encephalopathy no changes are observed in BuTJ activity.


The activity of Escherichia coli DNA-dependent RNA polymerase on DNA templates of different origin. The effect of cAMP. DNA isolated from different T phages served as a better template for the synthetic activity of unmodified Escherichia coli RNA polymerase in the in vitro system than did the host DNA. cAMP significantly stimulated the activity of such a preparation of RNA polymerase. The stimulation was more pronounced with the host DNA template than with phage DNA. However, the synthetic activity of Escherichia coli RNA polymerase was greater in the presence of cAMP than without it when phage DNA served as the template.


Serum hormone levels and tissue metabolism in pair-fed lean and obese Zucker rats. Obese Zucker rats were either pair-fed to their lean litter-mates or fed ad lib, to determine the effect of hyperphagia on serum hormone levels and tissue metabolism as indicated by enzyme activities and in vitro metabolite flux. Hyperphagia was shown to be non-essential for the elevation in serum insulin and suppression in serum growth hormone and prolactin in the genetically obese rat. It was also shown that the increased liver cell lipogenic rate was not dependent on hyperphagia in the obese rat and that adipose cell lipogenesis was not significantly altered in the pair-fed obese rat. The utilization of alanine for glucose synthesis in vitro was similar for both lean and obese rats, but its utilization for fatty acid synthesis was higher in the obese rat. Data is presented which suggest that the inhibitory effect of glucagon on liver lipogenesis is blunted in the obese rat.


Antidiuretic action of prolactin in the rat with diabetes insipidus. Rats with hereditary hypothalamic diabetes insipidus, devoid of endogenous ADH, exhibited a prompt antidiuresis when injected subcutaneously or intraarterially with ovine prolactin. The antidiuresis was accompanied by a decrease in free water clearance and an increase in urine osmolality without a change in osmolal clearance or creatinine excretion. Measurement of PAH and insulin clearances indicated that prolactin had no effect on renal plasma flow or glomerular filtration rate. Prolactin injection caused a transient decrease in urinary sodium excretion, but proximal tubular sodium reabsorption, estimated by lissamine green transit time, was unaffected. The antidiuretic effect of prolactin could not be attributed to ADH contamination of the ovine prolactin preparation. Kidney cyclic AMP content was increased significantly 5 min after injection of prolactin. Thus, prolactin has an antidiuretic effect similar to that which occurs as a result of ADH action on the kidney and does not require either the release or the presence of ADH in order to cause the antidiuresis. Further, the impaired water excretion cannot be attributed to an increase in proximal tubular sodium reabsorption or to alteration of renal hemodynamics. It is suggested that prolactin has a direct ADH-like action on the kidney resulting in antidiuresis.


Effect of Mg2, ATP and some analogs on phosphorylase phosphatase from adrenal cortex. The effect of Mg2, ATP and some of its analogs was studied on the spontaneously active and the ATP-Mg-dependent forms of phosphorylase phosphatase extracted from adrenal cortex. Inhibition of the spontaneously active form was observed with Mg2 (Ki - 9mM), ATP (Ki = 9micronM), 2'-doxy-ATP (Ki = 8 micronM), AtetraP (Ki = 9 micronM), AMP(CH2)PP (Ki = 11 micronM), ADP(CH2)P (Ki = 19 micronM), ADP(NH)P (Ki = 16micronM) and ADP (Ki = 25micronM). Activation of the ATP-Mg-dependent form was obtained with Mg2 (Ka = 0.55mM) (to a lower extent) and with ATP (Ka = 2micronM), 2'-deoxy-ATP (Ka = 6micronM) or AtetraP (Ka = 15micronM) in the presence of 0.5mM Mg2. Activation with AMP(CH2)PP was only observed in the presence of high concentrations (5mM) of Mg2 (Ka = 13micronM). No activation at all was observed with ADP(CH2)P or ADP(NH)P. Even though the activation of the ATP-Mg-dependent form does not seem to involve a kinase reaction, the stimulation by ATP or its analogs is rather specific, since it does not occur with analogs in which a methylene group or a nitrogen is substituted for the oxygen between the beta- and gamma-phosphates.


Spectral evidence for a liver mitochondrial cytochrome P450 involved in bile acid metabolism. Optical difference spectroscopy of liver mitochondria has revealed the presence of a cytochrome P450 species by its ligand reactions with carbon monoxide, metyrapone and diethylphenylphosphine. Its concentration of 0.15 nmol/mg mitochondrial protein is high enough to be detectable by ESR also. A microsomal contamination of the mitochondria could be excluded. Mitochondrial cytochrome P450 forms an enzyme-substrate complex with 5beta-cholestane-3alpha, 7alpha, 12alpha-triol with Ks value very similar to the Km value of the 26-hydroxylation of this substrate. This supports the existence in liver mitochondria of a cytochrome P450-dependent 26-monooxygenase for bile acid precursors, as previously postulated by us on the basis of a photochemical action spectrum.


Referral follow-up by clinicians in a community mental health center. In 1973 a study was conducted at the Western Psychiatric Institute in Pittsburgh to assess the extent of discrimination by clinicians against chronically ill clients in establishing initial treatment arrangements. Forty referrals (all simulated) were assigned to the center's five treatment teams; 20 of the referrals suggested a mild disorder, and 20 suggested a severe and chronic disorder. Premature termination of the study reduced the sample size from 40 to 29, and the findings regarding discrimination were inconclusive. However, the study revealed the unexpected finding that 34 per cent of the referrals received no follow-up. The author discusses the implications of that finding in relation to the basic principles of community mental health, and also to the large amounts of resources allocated to increasing service utilization in the center under study.


Confirmation of the assignment of the Chimpanzee thymidine kinase and galactokinase genes to chromosome 19. Chimpanzee-mouse hybrid cells were isolated by fusing chimpanzee HGPRT- cells and mouse TK- cells. Both biochemical and cytologic studies of these hybrid cells and BUDR resistant cells isolated from them showed that the TK and GaK genes are located on the chimpanzee chromosome 19.


Induction of cell division in BALB/c-3T3 cells by phorbol myristate acetate or bovine serum: effects of inhibitors of cyclic AMP phosphodiesterase and Na+-K+-ATPase. Cell division is induced in stationary cultures of BALB/c-3T3 mouse embryo cells without renewal of medium by addition of the tumor promoter, phorbol myristate acetate (PMA), or bovine serum. The addition of dbcAMP (10(-3) M) or other inhibitors of cAMP phosphodiesterase, papaverine (6.7 X 10(-6) M), Persantin (5 X 10(-5) M) or RO-20-1724 (10(-4) M), prevents cell replication induced by PMA or serum. In contrast, ouabain (10(-4) M) and N,N'-dicyclohexylcarbodiimide (10(-5) M), inhibitors of Na+-K+-ATPase activity, block the PMA-stimulated effect but do not inhibit serum-stimulated cell division. Several stages in the cell cycle are sensitive to dbcAMP addition. One is early in the G1 phase at the time of reinitiation of the cell cycle from a stationary (Go) phase, a second is associated with the G1-S transition, and a third with passage of cells from a post-S phase to mitosis. Based on observations of early morphological changes, responses of plasma membrane enzymes and effects of enzyme inhibitors, the stimulation of cell division in BALB/c-3T3 cells by PMA or serum appears to involve several membrane functions which may act in a cooperative manner.


Mycoplasma in African green monkey kidney cell cultures: biochemical detection and effects in virus-infected cells. Among a number of techniques for the detection of mycoplasmal contamination in African green monkey kidney (AGMK) cell lines, the assay of uridine phosphorylase activity is unsuitable because of the presence of high levels of endogenous enzymatic activity. A thymidine phosphorylase test, however, based on the chromatographic analysis of radiolabeled thymidine breakdown, turned out to be a simple and sensitive mycoplasma detection method. We found, using the latter technique, that 0.22-micrometer-filtered virus inocula could still transfer mycoplasma unless treated with diethyl ether. The effect of mycoplasmal contamination on the synthesis of simian virus 40 and adenovirus in AGMK cells was negligible under the conditions used (no depletion of arginine). Incorporation of radioactive thymidine in viral macromolecules, however, was inhibited severely by the presence of mycoplasma.


Effect of cyclic 3':5'-AMP derivatives prostaglandins and related agents on human chorionic gonadotropin secretion in human malignant trophoblast in culture. The secretion of human chorionic gonadotropin (hCG) is stimulated by addition of N6, O2'-dibutyryl cyclic 3':5'-AMP (dbcAMP) or theophylline to normal term placenta and human malignant trophoblast cells in vitro. To understand better the specificity of this process, malignant trophoblast cultures were incubated with 3':5'-cyclic AMP (cAMP) derivatives, prostaglandins and other agents for 1 to 3 days, and the secretion of radioimmunoassayable hCG was measured. Whereas dbcAMP was the most potent agent in stimulating secretion of hCG, the N6--and O2'-monobutyryl derivatives of cAMP and phosphodiesterase inhibitors (theophylline, papaverine, 3-isobutyl-1-methylxanthine) also increased the secretion of the hormone. A slight increase in hCG secretion was observed following addition of adenine. By contrast, butyrate, cAMP, cyclic 3':5'-GMP (cGMP), dbcGMP, 5'-AMP, adenosine, L-epinephrine and prostaglandins E1, E2, F1a and F2a were ineffective. Particulate fractions from sonicates of malignant trophoblast cultures contained adenylate cyclase activity which was stimulated more than 10-fold by NaF, but not by either catecholamines or prostaglandins. The relatively specific stimulation of hCG secretion suggested that a regulatory process involving cAMP may have physiological significance in the trophoblast.


Detection of mitogen-activated T and non-T lymphocytes by virus plaque assay. Virus plaque assay on the cells fractionated by unit gravity sedimentation. Virus plaque assay (VPA) was utilized for the quantitative evaluation of activated lymphocytes. We examined what types of cells, especially which of activated T and non-T lymphocytes, were detected as infective centres after infection with vesicular stomatitis virus. Marked increases in DNA synthesis and in virus-plaque forming cells (V-PFC) were observed not only during the activation of T lymphocytes with Con A, but also, though to a lesser extent, during the activation with lipopolysaccharide (LPS) of non-T lymphocyte preparations of nude spleen from which theta-positive lymphocytes and macrophages were completely depleted. The latter observation was further confirmed by the VPA on the populations enriched in LPS-activated non-T lymphocytes fractionated by the unit gravity sedimentation method. Fast sedimenting cells were found to be more active in DNA synthesis and contained more infective centres after infection than those sedimenting slowly and original unfractionated cells. Both the capacity for DNA synthesis and virus-replication were considered to be general properties accompanying lymphocyte activation.


Functional studies on human peritoneal eosinophils. A number of functional studies were performed on essentially pure eosinophil preparations obtained from the ascitic fluid of a patient with eosinophilic gastroenteritis. These cells responded to chemotactic factors including a bacterial factor, partially purified C5a, and factors generated from serum or ascitic fluid. The chemotactic activity generated in the patient's ascitic fluid was capable of attracting both neutrophils and eosinophils, was dependent on the presence of complement components, and was identified as C5a. Metabolic studies demonstrated that particle ingestion by eosinophils was associated with a marked increase in hexose monophosphate shunt activity ([1-14C]glucose oxidation), H2O2 formation ([14C]formate oxidation), superoxide anion generation, chemiluminescence, thyroid hormone degradation, iodination, and estrogen binding. This postphagocytic metabolic burst by eosinophils was qualitatively similar to that observed in neutrophils, but for several parameters the eosinophil response was greater than the neutrophil response.


Development of cell-mediated immunity to Epstein-Barr herpesvirus in infectious mononucleosis as shown by leukocyte migration inhibition. Eight patients with infectious mononucleosis, aged between 8 and 24, were studied for cell-mediated immunity by the in vitro leukocyte migration inhibition test at acute and convalescent stages. Follow-up studies were also carried out at up to 4 months after clinical illness. Cell-mediated immunity to Epstein-Barr virus (EBV) in the peripheral leukocytes from these patients was absent or incipient in all cases during the acute phase, although it was present in lymphocytes from a biopsied lymph node obtained from one of the patients. In contrast, cell-mediated immunity to EBV was detected readily in peripheral leukocytes obtained during convalescence and in the follow-up studies. A blocking factor that abrogated leukocyte migration inhibition induced by EBV antigen was detected in acute and convalescent sera obtained from six of eight patients, whereas serum antinuclear autoantibodies were detected in the two patients whose sera failed to block leukocyte migration inhibition. When sera were fractionated, this blocking effect was observed only in the serum immunoglobulin G fractions. In follow-up studies, neither the blocking factor nor the antinuclear autoantibodies were found in the sera collected.


Chemiluminescence spectra of human myeloperoxidase and polymorphonuclear leukocytes. The light emission spectra of myeloperoxidase-H2O2-Cl- and phagocytizing polymorphonuclear leukocytes were estimated by a computer simulation technique by using light transmittance data from nine band-pass filters. No shift in the chemiluminescence spectrum of either system was observed during the course of the reactions, suggesting that the light-generating mechanisms remain constant after their initiation. Transmittances were virtually identical for both myeloperoxidase-H2-O2-Cl- and polymorphonuclear leukocyte reactions, suggesting that the light-generating mechanisms are identical and leading to the estimation of nearly identical spectra. Both spectra were broad, with maximum light emission near 570 nm.


On the protection of E. coli against radiation lethality by ascorbate combined with tetracycline. The radioprotective action in E. coli ATCC 9637 of ascorbate added to media containing the weak sensitizer, tetracycline (effect described by Pittillo and Lucas (1967)), was found to be dependent on the presence of metal catalysts of the autoxidation of ascorbate. Thus, the protective action of ascorbate + tetracycline as well as the rate of autoxidation of ascorbate in this mixture were enhanced by 0.1 micron Cu, and these effects were counteracted by pyrophosphate probably through chelation of iron that contaminates phosphate. A suppression of metabolism is apparently involved in the combined action as judged by the decrease of incorporation of labelled uridine.


[Vitamin A-vitamin D3 relationship in growing rats]. A relation vitamin A - vitamin D3 exists in diet for growing rats. When this decreases from 5 (microgram A - IU D3) or 15 (IU A - IU D3) to 1,25 (microgram/IU) or 3,75 (IU/IU) growth, calcemia are increasing but vitamin A hepatic storage is decreasing. In other words for a same quantity of retinol, cholecalciferol's level in diet determines hepatic stores of vitamin A. General aspect of this question is discussed.


Subcellular distribution of thiamine-pyrophosphokinase and thiamine-pyrophosphatase activities in rat isolated enterocytes. Starting from mucosal cells, isolated from rat small intestine, subcellular fractionation was carried out. Four fractions were prepared and characterized by marker enzymes and electron microscopic examination: nuclei plus microvilli, mitochondria, microsomes and supernatant. Thiamine-pyrophosphokinase activity was localized mainly in the supernatant fraction, with minor amount in mitchondria and microsomes. On the contrary thiamine-pyrophosphatase activity was present only in the particulate fractions (especially in microsomes), being completely absent from the supernatant.


A superoxide-producing system in the conjunctival mucus thread. In normal sterile eyes, the conjunctival mucus thread is capable of reducing the vital stain iodonitrotetrazolium (INT). The greatly increased amount of INT reduction in bacterial conjunctivitis has been used as a clinical test for this disorder. We find that native superoxide dismutase, but not the heat inactivated enzyme, inhibits INT reduction by the conjunctival mucus thread in vitro as well as in vivo in sterile rabbit eyes. Furthermore, 3,4-dihydroxybenzoic acid (DHBA), a scavenger of superoxide radical (O2-), inhibits INT reduction by the mucus thread. We conclude that INT reduction by the mucus thread is due to a superoxide radical-producing system similar to that apparently responsible for the tetrazolium-reducing properties of granulocytes and other phagocytes. This oxygen radical-producing system may serve as a defense against infection and possibly as a mediator of the conjunctival inflammatory response.


Rapid detection of human cytomegalovirus and herpesvirus hominis IgM antibody by the immunoperoxidase technique. Immunoglobulin M (IgM) to human cytomegalovirus (CMV) and herpesvirus hominis (HVH, types 1 and 2) has been searched for in a group of patients with congenital and recent CMV and HVH infections and also in a group of patients with remote CMV and recurrent HVH infections, using the immunoperoxidase antibody technique (IPA) as compared to a technique using sucrose density gradient differential centrifugation. Both techniques detected the same positive samples. High IgM antibody titers (1:32-1:512) were observed in all cases of primary CMV and HVH infection, whereas low titers (1:8-1:16) were found in congenital infections. The IPA technique is sensitive, specific and useful for rapid diagnosis of recent and congenital CMV and HVH infections.


A novel approach to study the DNA of herpes zoster virus. Herpes zoster virus DNA was isolated from infected human embryo lung cells because it is released into the "Hirt supernatant". The buoyant density of the virus DNA was found to be slightly higher than that of cellular DNA. The molecular weight of this DNA was estimated to be 92 x 10(6) daltons by cosedimentation with T4 DNA in neutral sucrose gradients. As with the DNA of other herpesviruses, the DNA of herpes zoster virus is fragmented when denatured under alkaline conditions and is therefore "alkali-labile". Studies of virus DNA using reassociation kinetics reveal that the kinetic complexity of the DNA correlates with the genome size as estimated by sucrose gradient sedimentation.


The antibody response following hepatitis A infection. A specific IgM response to hepatitis A virus was detected in sera from patients suffering acute hepatitis A infection. The presence of virus-specific IgM in 19S components of acute and early convalescent phase sera was detected by immune electron microscopy and solid-phase radioimmunoassay. The presence of virus-specific IgM in whole serum specimens was demonstrated by indirect immunoferritin labeling. Following acute infection, however, the major immunoglobulin response appears to be IgG, since titers of specific 7S and whole serum antibody were very similar.


Evaluation of perfluoroctylbromide for lymphography in the dog: comparison with ethiodol. The efficacy and safety of perfluoroctylbromide as a diagnostic contrast agent for direct lymphography was studied in mongrel dogs. This radiopaque perfluorocarbon has several advantages over Ethiodol. The liquid compound has injection times  one-fifth of that required for Ethiodol. When dosages were three to four times that necessary for radiograms, the lungs of perfluoroctylbromide dogs tolerated the increase better than the Ethiodol dogs. Although the radiopacity is less, radiographs were acceptable. The less radiopacity of the fluoroctylbromide nodes may be of greater significance in the larger body of the human.


Propagation of a B-tropic murine leukemia virus in N-type cells in the presence of different murine sarcoma viruses. B-tropic MuLV, WN1802B, was converted to NB-tropic after 5 days of propagation in its nonpermissive N-type MLg or C3H2K cells in the presence of the S + L - MuSV, but not in the presence of the Harvey or Kirsten strains of MsSV.


Ultrastructure of hepatocellular carcinoma in a cirrhotic liver. Hepatoma cells, though sharing many similarities with non-neoplastic hepatocytes, showed conspicuous alterations--increased nuclear/cytoplasmic ratio, intranuclear invapinations of cytoplasm, lipoid material, high mitotic activity, and the presence of abundant small fat droplets and glycogen in the cytoplasm. "Capillarization" of sinusoids was a constant feature with the appearance of junctions between endothelial cells, deposition of fibrillary material in Disse's spaces, flattening of hepatocyte microvilli and deposition of basement-membrane-like material. Abundant microtubules and the presence of annulate lamellae were other features noted in the tumor cells.


[Myoblastoma of the larynx (author's transl)]. The case of a 35-year-old man in whom a broad-based tumour of the left vocal cord was found to be the cause of hoarseness of 4 months' duration is reported. The tumour was completely removed and proved to be a myoblastoma. Twelve months postoperatively there was no recurrence. Whether these are true neoplasms in all cases is still uncertain. Recurrence, multifocal origin and malignant change, factors which cannot be excluded, underline the need for the long-term follow-up.


[Observations during tonsillectomy in angiomatous phakomatoses of the head (author's transl)]. The problems encountered during tonsillectomy in a patient with a vascular malformation (flame nevus), mandibular hypertrophy, and extensive arteriovenous malformations involving the external carotid arteries are described. The inclusion of the patient in the Sturge-Weber or Klippel-Trenaunay Syndromes is discussed.


[Computer tomography in otorhinolaryngology--a preliminary report (author's transl)]. The diagnostic possibilities of computer tomography in otorhinolaryngology are presented with the aid of typical and unusual cases. Good topographical demonstration of pathologies and the assessment of tissue densities with this method are emphasized.


Effect of physical training on control mechanisms of lipolysis in rat fat cell ghosts. Fat cell ghosts and homogenates of fat cells were used to study the influence of training on the regulatory system for lipolysis in adipose tissue of female rats. A training effect was identified from elevated succinate dehydrogenase activities in the soleus and plantaris muscles. Neither basal nor maximal (NaF-stimulated) adenylate cyclase activities per mg protein of fat cell ghosts were altered by training. Fluoride-stimulated adenylate cyclase activity per microgram DNA was lower in the trained than untrained group. Adenylate cyclase activities in response to norepinephrine expressed either on a per mg protein or per microgram DNA basis were lower (P less than 0.05) in fat cell ghosts from trained rats. Phosphodiesterase activity was higher (P less than 0.05) in fat cell ghosts from trained rats for cyclic AMP concentrations of 1--5.0 micrometer. The apparent Km's of phosphodiesterase were 1.19 and 2.0 micrometer of cyclic AMP for the untrained and trained groups, respectively (P less than 0.05). Protein kinase activity in the supernatant fraction of homogenates of fat cells was unchanged due to training. The overall effect of training was to blunt the system for cyclic AMP production in rat adipocytes. This may explain, at least partially, the lower plasma free fatty acid levels observed in trained compared to untrained persons during submaximal exercise.


Limits on VA/Q distributions from analysis of experimental inert gas elimination. Distributions of ventilation-perfusion ratios (VA/Q) actually present in the lung cannot be exactly recovered using current inert gas elimination methods, principally because of the limited number of gases and errors in their measurement. The amount of information that can be gained is studied here. When six gases are used the results are difficult to visualize so that a graphical analysis is first given for only two gases. Methods are proposed for 1) the probabilistic description of retentions compatible with a set of measured values of all six gases, and 2) the placing of limits on the associated VA/Q distributions. It is found that the variability among distributions with compatible retentions depends greatly on the particular set of data. Distributions consisting of a single or of two separated narrow modes can be identified reliably.


Partial purification of ferredoxin from Ruminococcus albus and its role in pyruvate metabolism and reduction of nicotinamide adenine dinucleotide by H2. Extracts of Ruminococcus albus were not able to convert pyruvate to acetyl phosphate, CO2, and H2 after passage through a diethylaminoethyl (DEAE)-cellulose column. Activity was restored by a brown protein fraction eluted from the column with 0.4 M Cl-. The protein was partially purified and shown to have the spectral and biological characteristics of ferredoxin. R. albus ferredoxin, Clostridium pasteurianum ferredoxin, and methyl viologen restored activity for pyruvate decomposition by DEAE-cellulose-treated R. albus extracts. R. albus or C. pasteurianum ferredoxin restored the ability of DEAE-cellulose-treated C. pasteurianum extracts to form H2 and acetyl phosphate from pyruvate. Ferredoxin-free extracts of R. albus reduced nicotinamide adenine dinucleotide (NAD) when supplemented with R. albus or C. pasteurianum ferredoxin or with methyl viologen. These extracts reduced NADP with H2 poorly unless both ferredoxin and NAD were added, which indicates the presence of an NADH:NADP transhydrogenase. Flavin mononucleotide and flavin adenine dinucleotide were rapidly reduced by H2 by ferredoxin-free extracts in the absence of ferredoxin.


Mutants of luminous bacteria with an altered control of luciferase synthesis. Arginine is known to increase the luminescence in vivo and in vitro of the marine bacterium Beneckea harveyi growing in minimal medium. Mutants in which this arginine effect is either diminished, or absent were isolated as bright clones on a minimal medium after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. On a minimal medium both with and without added arginine and also on complex medium, these "minimal bright" mutants produce higher levels of luminescence than the wild type both in vivo and in vitro. This is attributed to the production of an increased amount of luciferase, which itself is wild type in terms of its specific activity.


Regulation of the arginine dihydrolase pathway in Clostridium sporogenes. Arginine deiminase activity was induced during the vegetative growth of Clostridium sporogenes. The enzyme was sensitive to catabolite repression. The other enzymes of the arginine dihydrolase pathway, namely, ornithine carbamoyl-transferase and carbamate kinase, did not show such variation.


Role of cyclic adenosine 3',5'-monophosphate on cessation of respiration in ultraviolet-irradiated Escherichia coli. The addition of cyclic adenosine 3',5'-monophosphate (cAMP) to ultraviolet-irradiated Escherichia coli B/r cultures causes additional cells to cease respiring and to die. These effects of cAMP are greater on glucose-grown cells, where the effects of ultraviolet radiations alone are smaller and where the intracellular concentrations of cAMP are known to be lower.


Release of periplasmic enzymes from Escherichia coli by penicillin-ethylenediaminetetraacetate treatment. When Escherichia coli cells are converted into spheroplasts by penicillin treatment, none of the periplasmic enzymes is released. However, incubation of the penicillin-induced spheroplasts in a medium containing ethylenediaminetetraacetic acid caused the release of endonuclease I and cyclic phosphodiesterase but not of beta-galactosidase.


Spore coat protein and enterotoxin synthesis in Clostridium perfringens. Polyacrylamide gel profiles of Clostridium perfringens spore coat protein revealed four and occasionally five components. Pulse-chase experiments indicated that synthesis of coat protein polypeptide and enterotoxin was an early sporulation event. However, maximum synthesis occurred coincident with the onset of heat resistance.


A specific method for the determination of threonine in rat blood plasma using aldehyde dehydrogenase. A simple and sensitive method for the determination of threonine in rat blood plasma using aldehyde dehydrogenase after oxidation with periodate was developed. By the present method, threonine could be completely discriminated from serine and determined at the nanomole level. The amount of threonine in rat blood plasma obtained by the present method coincided well with the value determined on an amino acid analyzer.


The sulfhydryl groups involved in the active site of myosin B adenosinetriphosphatase. II. Effect of modification of the Sa thiol group on superprecipitation and clearing. The effect of Sa modification with NEM, which activates Mg2+-ATPase through an enhancement of the association of actin and myosin, was investigated on the superprecipitation, clearing and Mg2+-ITPase of myosin B with reference to the effect of S1-blocking. 1. Superprecipitation induced by ATP was markedly enhanced by Sa-blocking even at high concentrations of Mg2+ and substrate; this may be due to an increase in the affinity of myosin and actin on blocking Sa. 2. Nevertheless, neither ITP-induced superprecipitation nor Mg2+-ITPase was affected by Sa modification. 3. Blocking of S1 brought about the inhibition of ATP- and ITP-induced superprecipitation and Mg2+-ITPase activity, suggesting that S1-blocking decreases the affinity of myosin and actin. 4. Sa-blocked myosin B showed greater resistance to clearing by ATP, especially in the presence of Ca2+ ions, whereas in the clearing response of actomyosin gel to PPi no difference between Sa-blocked and unmodified myosins B was observed. On the other hand, the clearing response of myosin B became more sensitive to both ATP and PPi on blocking S1. Based on the above results and preliminary data suggesting that Sa is located in LMM, the interaction of myosin filaments and actin filaments under physiological conditions is discussed.


Proteolysis of apoproteins in human serum low density lipoprotein. Proteolytic treatment of human serum low density lipoprotein (LDL) resulted in the observation of interesting time-dependent changes in the sodium dodecyl sulfate-polyacrylamide gel electrophoretic pattern of apo-LDL. Five major fragments with well-defined relative mobilities appeared within 30 min of protease treatment. Prolonged treatment with subtilisin caused changes in the amount of peptides in each of the five bands but their positions on the gel remained unchanged. Periodic acid-Schiff base staining of the gel showed a proteolytic fragment with an apparent molecular weight of 110.000 (actually a cross-linked dimer of two peptides with molecular weights of 77,000 and 68,000) to be a carbohydrate-bearing peptide that was most resistant to further proteolysis and therefore responsible for the interaction between the digested LDL and concanavalin A.


Effects of purine nucleotides on photosynthetic electron transport in isolated chloroplasts. The effects of guanylates and inosinates (and adenylates) on phosphorylation, ferricyanide reduction, and light-induced H+ uptake in spinach chloroplasts were studied. GDP, GTP, IDP, and ITP (but not GMP and IMP) stimulated the light-induced H+ uptake and partially inhibited ferricyanide reduction. Phosphate, arsenate, and phlorizin increased the extent of inhibition by these nucleotides and decreased the values of their apparent dissociation constants for the inhibition process. In the presence of phosphate (or arsenate), restoration of ferricyanide reduction from the level inhibited by guanylates and inosinates was observed as phosphorylation (or arsenylation) proceeded. These results suggest that phosphorylation of GDP and IDP as well as ADP takes place after two steps of nucleotide binding to the chloroplast coupling factor 1. The apparent dissociation constants of GDP and IDP for these two binding steps were estimated to be about 34 and 38 muM for the first and 110 and 160 muM for the second step, respectively (at pH 8.3, 15 degrees C). Above pH9, the ratio (P/delta-e) of the extent of phosphorylation to the increment of electron transport from the basal level measured in the presence of [ATP + Pi] or [ADP + Pi+ phlorizin], became increasingly large. When the electron transport level inhibited by dicyclohexyl-carbodiimide was taken to be the basal activity, the P/delta-e ratio remained almost constant (approximately 1) from pH 7.0 up to 10.


A novel nuclear relaxation approach for estimating distance between enzyme- and nucleotide-bound metal ions at the catalytic site of pyruvate kinase. This communication introduces a nuclear relaxation approach for an estimation of the distance between two paramagnetic metal ion sites on a metal-activated enzyme. The method is based on the existence of an exchange of unpaired electron spin magnetizations between the two metals via energy-conserving concerted mutual spin flips which arise from time-dependent dipolar interactions of the electronic magnetizations. This cross-relaxation of electronic magnetizations depends on the inverse sixth power of the intermetal distance and may, under suitable conditions, affect the longitudinal relaxation rate of inner sphere water protons by altering the electron-proton dipolar correlation time when the latter is dominated by electron spin relaxation. The technique is applied to estimate the distance of 5.2 +/- 0.9 A between Mn2+ and Cr3+ in the pyruvate kinase-Mn2+-ATPCr3+ complex and indicates the existence of a van der Waals contact between the hydration spheres of the enzyme- and nucleotide-bound metal ions.


Inhibition by lead ion of Electrophorus electroplax (Na+ + K+)-adenosine triphosphatase and K+-p-nitrophenylphosphatase. Inorganic lead ion in micromolar concentrations inhibits Electrophorus electroplax microsomal (Na+ + K+)-adenosine triphosphatase ((Na+ + K+)-ATPase) and K+-p-nitrophenylphosphatase (NPPase). Under the same conditions, the same concentrations of PbCl2 that inhibit ATPase activity also stimulate the phosphorylation of electroplax microsomes in the absence of added Na+. Enzyme activity is protected from inhibition by increasing concentrations of microsomes, ATP, and other metal ion chelators. The kinetics follow the pattern of a reversible noncompetitive inhibitor. No kinetic evidence is elicited for interactions of Pb2+ with Na+, K+, Mg2+, ATP, or p-nitrophenylphosphate. Na+- ATPase, in the absence of K+, and (Na+ + K+)-NPPase activity at low [K+] are also inhibited. ATP inhibition of NPPase is not reversed by Pb2+. The calculated concentrations of free [Pb2+] that produce 50% inhibition are similar for ATPase and NPPase activities. Pb2+ may act at a single independent binding site to produce both stimulation of the kinase and inhibition of the phosphatase activities.


Substrate and effector specificity of a guanosine 3':5'-monophosphate phosphodiesterase from rat liver. Guanosine 3':5'-monophosphate phosphodiesterases, which appear to be under allosteric control, have been partially purified from rat liver supernatant and particulate fractions. The preferred substrate for both phosphodiesterases was cGMP (Km values: cGMP less than cIMP less than cAMP). At subsaturating concentrations of substrate, the phosphodiesterases were stimulated by purine cyclic nucleotides. The order of effectiveness for activation of cyclic nucleotide hydrolysis was cGMP greater than cIMP greater than cAMP greater than cXMP. Using cAMP derivatives as activators of cIMP hydrolysis, modifications in the ribose, cyclic phosphate, and purine moieties were shown to alter the ability of the cyclic nucleotide to activate the supernatant enzyme. cGMP, at concentrations that stimulated cyclic nucleotide hydrolysis, enhanced chymotryptic inactivation of the supernatant phosphodiesterase. At similar concentrations, cAMP was not effective. It appears that on interaction with appropriate cyclic nucleotides, this phosphodiesterase undergoes conformational changes that are associated with increased catalytic activity and enhanced susceptibility to proteolytic attack. Divalent cation may not be required for the nucleotide-phosphodiesterase interaction and resultant change in conformation.


Synthesis of plasma lipoproteins by the isolated perfused liver from the fasted and fed pig. Livers from fasted or fed pigs were perfused for 5 h with Krebs-Ringer bicarbonate buffer containing human erythrocytes, bovine serum albumin, glucose, and amino acids. Liver viability was estimated by color, consistency, portal pressure, bile flow, electrolyte changes, and glucose levels in the perfusate, urea synthesis, [1-14C]leucine incorporation into protein, oxygen uptake, and histological examination. It was shown that the liver was maintained in good condition throughout the perfusions. The apolipoprotein B (apoB) and apolipoprotein A-I (apoA-I) in the perfusate were measured by solid phase radioimmunoassay. In the fasted state, the amount of apoB released was greatest in the low density lipoprotein (LDL) fraction and the amount was especially high during the 1st h. There was no increase of apoB in this fraction by feeding. The apoB in the very low density lipoprotein (VLDL) fraction was less than that in the LDL fraction in the fasted state, and it increased more than 2-fold in the fed animals. The amount of apoA-I was greatest in the 1.21 bottom fraction and was relatively small in the high density lipoprotein (HDL) fraction. The HDL fraction contained approximately one-twentieth as much apoA-I as the 1.21 bottom fraction in the fasted condition. In the fed state, apoA-I in the HDL fraction increased markedly, although the amount was still less than in the 1.21 bottom fraction.


Regulation of protein degradation in normal and transformed human cells. Effects of growth state, medium composition, and viral transformation. In WI-38, a normal human fibroblast, the rates of degradation of short lived and long lived proteins are identical whether the cultures are growing exponentially or are density-inhibited. Replacement of the growth medium with fresh medium does not alter these rates. In VA-13, an SV-40 transformed derivative of WI-38, the rates of protein degradation are also independent of growth rate and fresh medium. However, in both WI-38 and VA-13 the rate of long lived protein degradation increases as the serum concentration is reduced below 5%. After complete serum withdrawal, the rate increases by 60 to 100% in both cell types. Withdrawal of arginine and phenylalanine triples the rate of long lived protein degradation, while addition of 10% dialyzed serum to this amino acid-deficient medium reduces the effect to twice that of the controls. Incubation of both types of cells in phosphate-buffered saline also increases protein degradation. This effect is reduced by glucose, albumin, and dialyzed serum. Therefore, the rate of protein degradation is independent of growth rate in normal and transformed human cells. However, the rate of degradation is closely coupled to certain medium alterations.


Purineless death: ribosomal RNA turnover in a purine-starved ade- mutant of Chinese hamster cells. When V79 pur 1, a purine-requiring auxotroph of a Chinese hamster cell line, is deprived of adenine, nucleic acid and protein synthesis decline rapidly. However, on continuous starvation RNA and DNA synthesis recommences to reach approximately 30% of the normal level between 12 to 24 h starvation. This is accompanied by a rise in the intracellular nucleotide pool. Utilizing mengovirus, which gives a productive infection in V79 pur 1 cells even under conditions of starvation, we can show that rRNA is preferentially degraded and provides the nucleotides for RNA synthesis. Thus "purineless" death in mammalian cells is accompanied by turnover of stable RNA.


Protein kinases in brown adipose tissue of developing rats. Electrophoretic separation and assay of soluble protein kinases on polyacrylamide gels and a study of their properties and changes during development. Protein kinase activity was detected and assayed directly on polyacrylamide gels after disc electrophoresis of the 100,000 X g supernatant fraction of brown adipose tissue of infant rats. Nine major bands of activity were detected, eight of which could be stimulated by cAMP or inhibited by the cAMP-dependent protein kinase inhibitor protein. This electrophoretic technique revealed heterogeneity in the cAMP-dependent protein kinase activity eluted from DEAE-cellulose by high concentrations of salt, but not in the peak of activity eluted by low concentrations of salt. The catalytic properties and substrate specificities of the kinases in the various bands were studied while the enzymes were still in the gels. The activity in each band differed from each of the others in at least one of these properties. The activities of the protein kinases in brown fat changed as the animals grew, and each band exhibited a distinct and unique developmental pattern. The major changes in kinase activities occurred in the immediate post-parturition period, then at 15 days after birth and at weaning. These developmental stages coincide with the periods during which the tissue undergoes changes in the rate of its proliferation, differentiation, and functional activity.


5-Methylcytosine content of rat hepatoma DNA substituted with bromodeoxyuridine. The aim of these experiments was to test whether incorporation of bromodeoxyuridine into DNA affects DNA methylation. Rat hepatoma (HTC) cells in culture were labeled for two generations with [14C]bromodeoxyuridine and [3H]thymidine to yield DNA which was 2.1, 20.6, 52.6, and 95.0% bromodeoxyuridine-substituted in the newly made strands. The DNA then was fractionated into highly repetitive, moderately repetitive, and single copy sequences. As determined by a comparison of 14C and 3H counts per min, the percentage of substitution with bromodeoxyuridine was found to be the same in each repetition class. The 5-methylcytosine content of each fraction was determined using high pressure liquid chromatography. It was found that bromodeoxyuridine, even at a level of substitution into newly mad DNA of 95%, has no effect on the 5-methylcytosine content of DNA. At all levels of bromodeoxyuridine substitution, highly repetitive DNA has slightly more 5-methylcytosine (3.0% of total cytosine) than does single copy DNA or moderately repetitive DNA (2.3%). The 5-methylcytosine content of whole HTC DNA is the same as that of rat liver DNA (2.4%).


Crystallographic data for chicken liver fructose bisphosphatase. Large, single crystals of fructose bisphosphatase have been obtained under a variety of conditions. Preliminary crystallographic analysis reveals that the space group is R3, the cell dimensions on the hexagonal axes are a = b = 304 A and c = 80.4 A, and there is one tetramer per asymmetric unit.


Ca2+-dependent regulation of cyclic-AMP phosphodiesterase by parvalbumin. Carp parvalbumin has been shown to activate rat brain phosphodiesterase in a Ca2+-dependent manner. The concentration of Ca2+ required for half-maximal stimulation is 1.4 X 10(-7) M, whereas rat testis Ca2+-dependent regulator (CDR) of phosphodiesterase required 1.2 X 10(-6) M Ca2+. The difference in the slopes of the two curves demonstrated that the activation induced by parvalbumin was not the result of a small contamination by CDR. In addition, it has been shown that Ca2+ binding to parvalbumin parallels its activation of phosphodiesterase. These data suggest that Ca2+ must bind to a single specific metal binding site before phosphodiesterase can be fully activated.


The role of 2,4,5-trihydroxyphenylalanine in melanin biosynthesis. Both 3,4-dihydroxyphenylalanine and 2,4,5-trihydroxyphenylalanine were oxidized with periodate and mushroom tyrosinase to determine whether the latter compound is an intermediate in melanin biosynthesis. Matrix analysis of the spectra obtained with a rapid scan spectrophotometer and comparison of the spectra of quinone intermediates with model quinones disclosed that, although 2,4,5-trihydroxyphenylalanine can be oxidized to 2-carboxy-2,3-dihydroindole-5,6-quinone (dopachrome), this oxidation proceeds through a stable intermediate, 5-(2-carboxy-2-aminoethyl)-2-hydroxy-1,4-benzoquinone, which does not appear in the oxidation of 3,4-dihydroxyphenylalanine to dopachrome. Thus, these studies are in agreement with the original postulate, that 4-(2-carboxy-2-aminoethyl)-1,2-benzoquinone and leukodopachrome are the intermediates in the major pathway for dopachrome synthesis.


Self-association of apo-C-I from the human high density lipoprotein complex. The molecular properties of apo-C-I, isolated from the human high density lipoprotein complex, have been evaluated as a function of pH, solvent composition, and protein concentration by sedimentation equilibrium and circular dichroic measurements. This protein self-associates in aqueous solution at neutral pH with concomitant changes in secondary structure. In contrast, in the acid pH range, apo-C-I is monomeric and its ellipticity is independent of protein concentration. The results are discussed in terms of the interpretation of experiments where changes in the physical properties of apolipoproteins have been used to monitor ligand binding and lipid-apolipoprotein recombination.


Envelope composition and antibiotic hypersensitivity of Escherichia coli mutants defective in phosphatidylserine synthetase. Mutants of Escherichia coli K12, defective in phosphatidylserine synthetase (pss), can be isolated as temperature-sensitive, conditional lethals. When cultivated at intermediate temperatures (30 degrees), such mutants contain approximately 3 times more phosphatidylglycerol plus cardiolipin (and less phosphatidylethanolamine) than normal. We now wish to report that, under these conditions, the pss-8 mutant is hypersensitive to certain antibiotics, especially to streptomycin, kanamycin, and gentamicin, although also to ampicillin and novobiocin. At 30 degrees, the membrane protein and fatty acid composition of pss-8 is nearly normal, i.e. identical with an isogenic pss+ organism. Radiochemical labeling and bacteriophage growth studies show that lipopolysaccharide is also unaltered. Therefore, the antibiotic hypersensitivity of pss-8 differs from previously reported hypersensitivities, associated with lipopolysaccharide defects. These results suggest that the polar phospholipid headgroups may play an important role in maintaining the barrier function of the outer gramnegative membrane and that putative inhibitors of the phosphatidylserine synthetase might potentiate the action of numerous antibiotics currently in clinical use.


Binding of viral glycoprotein mRNA to endoplasmic reticulum membranes is disrupted by puromycin. Previous studies showed that the glycoprotein (G) of vesicular stomatitis virus is synthesized in association with the endoplasmic reticulum (ER) membrane and that all G mRNA co-fractionates with ER membrane. Here, we show that treatment of infected cells with puromycin results in dissociation of G mRNA, and presumably the associated ribosomes, from the ER membrane. Even it extracts from treated cells are kept at low ionic strength (0.01 M KCl), over 80% of G mRNA is found unattached to membranes. There is no evidence for direct interaction of GmRNA with membranes; rather, the linkage apparently is mediated by the nascent G polypeptide.


Binding of [3H]oxytocin to cells isolated from the mammary gland of the lactating rat. More than 90 percent of the cells isolated from the mammary gland of lactating rats with 0.1 percent collagenase were viable by dye exclusion. Myoepithelial cells comprised about one-third of the mammary cells and appeared to be morphologically intact in electron micrographs. [(3)H]Oxytocin-binding activity was localized in an enriched myoepitheial cell fraction obtained by density gradient centrifugation of the isolated cells. The amount of [(3)H] oxytocin bound at 20 degree C and pH 7.6 was proportional to the concentration of oxytocin and the number of cells, reaching a steady state by 40 min. About 0.45 fmol of oxytocin were bound per 10(6) cells. There was a single class of independent binding sites with an apparent K(d), estimated from equilibrium conditions, of 5 nM. This value agrees within experimental error with the value calculated from the ratio of reverse to forward rate constants (5.8 x 10(-4)s(-1) and 2.2 x 10(5) M(-1)s(-1), respectively), consistent with a single-step model for the interaction of oxytocin with binding sites on the cells. Erythrocytes bound only 3.5 percent of the amount of oxytocin bound by an equal number of mammary cells. Oxytocin analogues competed with [(3)H]oxytocin for binding sites in the following order: [deamino]oxytocin > [4-threonine]oxytocin > oxytocin > [O- methyltyrosine]oxytocin > [8-lysine]vasopressin; [lysine]-bradykinin and [4-proline]oxytocin were not inhibitory in the dose ranges tested. These results demonstrate that isolated mammary cells possess oxytocin receptors with properties comparable to those found in broken mammary cell preparations.


The control of human WI-38 cell proliferation by extracellular calcium and its elimination by SV-40 virus-induced proliferative transformation. The proliferative activity of diploid human WI-38 cells in sparse cultures depends on the extracellular concentration of free (or physiologically available) calcium, and cultivation in a medium having a calcium concentration of 0.1 mM or less gradually, but reversibly, arrest their proliferative development in the prereplicative (G1) phase of the cell cycle. Calcium's proliferative control of this cell type is eliminated by proliferative and morphological transformation by the oncogenic SV-40 virus, and the proliferative activity of SV-WI-38 cells in sparse cultures is unaffected by variation of the extracellular free calcium concentration between 0.00 and 1.25 mM.


A cell membrane alteration specifically induced by SV40 transformation. Transformation of mouse 3T3 cells by SV40 results in a specific membrane modification which renders cells resistant to the killing action of the lipophilic antibiotic Amphotericin B. This alteration is under genetic cellular control and is specific for SV40 transformation since transformation with polyoma or mouse sarcoma viruses does not confer resistance to the antibiotic. Analogous resistance is induced by SV40 transformation of primary human fibroblast cells. The acquired resistance is not due to decreased binding of Amphotericin B and is partially reversed if cells are grown in the presence of cholesterol. The results are interpreted as a specific change of sterol structure of the membrane or the loss of a minor cholesterol fraction responsible for the killing action of the antibiotic.


High-performance liquid chromatographic analysis of dianhydrogalactitol in plasma by derivatization with sodium diethyldithiocarbamate. A high-performance liquid chromatographic method is described for measuring submicrogram quantities of dianhydrogalactitol, a promising anti-neoplastic agent, in plasma. The drug is derivatized directly in plasma with sodium diethyldithiocarbamate to form a bis(dithiocarbamoyl) ester which absorbs UV light at 254 nm (am 17,000). The derivatized product is then extracted quantitatively into chloroform and separated by normal phase chromatography (muBondpak CN column). Dianhydrogalactitol concentration below 50 ng/ml of plasma can be detected in the eluent.


Vitamin D metabolism and the response to 1,25-dihydroxycholecalciferol in Osteoporosis. The metabolism of isotopically-labelled cholecalciferol and the response to small doses of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) was studied in a group of women with osteoporosis presenting with crush vertebral fracture. No abnormality of vitamin D metabolism was detected. The administration of 1 microgram 1,25-(OH)2D3 for between 8 and 20 days was associated with an increased intestinal absorption and urinary excretion of calcium but caused no improvement in calcium balance. There was a small but significant rise in serum calcium and phosphorus and significant reduction in immunoassayable parathyroid hormone levels during treatment. It is concluded that 1,25-(OH)2D3 is unlikely to be of value in the management of osteoporosis.


Plasma testosterone profiles in Cushing's syndrome. Elevated plasma testosterone levels were found in 8 women with Cushing's disease and oligo-or amenorrhea and/or hirsutism. In 4 men with Cushing's syndrome either due to adrenal hyperplasia or adenoma, plasma testosterone levels were lowered. Three of these 4 men complained of impotence or loss of libodo. Evidence for a major adrenal origin of the elevated testosterone values in the women with Cushing's disease was derived from the parallel suppression of cortisol and testosterone during dexamethasone administration, the testosterone responsiveness to ACTH and its dramatic fall after adrenalectomy. In the men with Cushing's syndrome the lowered plasma testosterone values were further suppressed by high doses of dexamethasone irrespective of concomitant cortisol suppression. Adrenalectomy or adenotomy restored the decreased plasma testosterone levels to normal. In women with Cushing's syndrome adrenal hyperandrogenism may account for the sexual and gonadal disturbances, in men glucocorticoid induced suppression of Leydig cell function may be responsible.


Comparison of antibody-dependent cellular cytotoxicity and complement-dependent antibody lysis of herpes simplex virus-infected cells as methods of detecting antiviral antibodies in human sera. An antibody-dependent cellular cytotoxicity (ADCC) assay was used to detect antibodies to the herpes simplex viruses in humans sera. The assay utilized the release of 51Cr from BHK-21 cells infected with the viruses, hamster peritoneal exudate cells as effector cells, and antiviral antibodies in human sera. The technique was found to be far more sensitive than complement-dependent antibody lysis of infected cells and virus neutralization. The ADCC assay was useful in detecting antibodies in sera that had low titers or no antibodies detectable by other methods. In a sample of 100 sera from university students, 40 were positive by complement-dependent lysis whereas 73 were positive by ADCC. Of 400 sera from women with cervical cancer, 17 did not have detectable antibodies by microneutralization or complement-dependent lysis; however, all sera were positive by ADCC, suggesting that all of the women had been infected in the past with one or both types of herpes simplex virus.


Quantitation of antibody to non-hemagglutinating viruses by single radial hemolysis: serological test for human coronaviruses. A single radial hemolysis test was developed for quantitation of specific antibody to non-hemagglutinating viruses. With the human coronaviruses as models, this test utilizes the binding properties of the chromic cation to attach viruses to glutaraldehyde-treated sheep erythrocytes. The most satisfactory system consisted of stabilizing washed sheep erythrocytes with 0.0073% glutaraldehyde for 15 min at 23 degrees C, binding a high concentration of virus to a 25% erythrocyte suspension with 0.0016% chromic chloride for 20 min at 23 degrees C, stopping the reaction with phosphate-saline, and finally mixing the treated, rewashed cells with complement and agarose at 45 degrees C to prepare a slide gel. The gel mix, which was dispensed in plastic plates (23 by 73 mm) in 3-ml volumes, consisted of 1% agarose, 0.1% sodium azide, 5% reconstituted complement, and 0.82% treated cells. Wells 2 mm in diameter were loaded with 5 mul of antiserum, incubated for 18 h at 4 degrees C for diffusion of antiserum and fixation of complement, and then incubated for 8 to 24 h at 37 degrees C for development of hemolysis zones. The diameter of a zone was linearly related to antibody concentration, as determined by conventional serological tests. This single radial hemolysis test was applicable to human and animal coronaviruses and to selected serotypes of the adenovirus, picornavirus, rhabdovirus, and rotavirus groups.


Solid-phase enzyme immunoassay for immunoglobulin M antibodies to cytomegalovirus. A sensitive, solid-phase enzyme immunoassay for the detection of immunoglobulin M antibodies to cytomegalovirus is described. The results of the enzyme immunoassay correlated well with those obtained by an indirect immunofluorescence method. Horseradish peroxidase proved to be a more sensitive label than alkaline phosphatase. Nonspecific reactions, occurring with commercially available cytomegalovirus antigens, could be avoided by using a nuclear antigen prepared from sonically disrupted nuclei of cytomegalovirus-infected cells.


Gelatin neutralization of the inhibitory effect of sodium polyanethol sulfonate on Neisseria meningitidis in blood culture media. The inhibitory effect of sodium polyanethol sulfonate (0.05%) upon growth of Neisseria meningitidis was found to be neutralized by adding gelatin (l.1%) to the growth medium. The neutralizing effect was demonstrated in solid medium, as well as in nutrient broth for blood cultures. The findings parallel those of Wilkins and West (6) regarding gelatin neutralization of the inhibitory effect of sodium polyanethol sulfonate on Peptostreptococcus anaerobius.


Maintenance of viability and comparison of identification methods for influenza and other respiratory viruses of humans. A comparison of Hanks balanced salt solution, veal infusion broth (VIB), and charcoal viral transport medium for maintaining viability of type A influenza virus indicated approximately equal survival of virus on all three media at -70 and 4 degrees C, whereas at 25 degrees C virus survived best in VIB. VIB supplemented with bovine serum albumin was used as transport medium in a community-wide surveillance of febrile respiratory disease for influenza viruses. Unfrozen throat swab specimens were placed in VIB and stored at 4 degrees C for up to 5 days without effect on isolation frequencies of either type A or type B influenza virus or type 1 or type 3 parainfluenza virus. Comparison of indirect immunofluorescence with hemadsorption for detection of type A influenza virus in rhesus monkey kidney cultures revealed a requirement for at least five fluorescing cells to eliminate false positive indirect immunofluorescence tests and at least 3 days of incubation to eliminate false negative tests when compared with hemadsorption at later times. Detection frequencies for the two methods after 2 and 3 days of incubation were not significantly different.


Preparation and evaluation of a noninfectious monkey pox virus vaccine. Monkey pox virus was mechanically disrupted by low temperature and high pressure into soluble and insoluble fractions. Soluble fractions elicited virus-neutralizing antibodies (1:20 to 1:160) in rabbits, whereas the insoluble (in saline) fractions did not (less than 1:5). No infectious virus was detected after the disruption procedure. Rhesus monkeys immunized with the soluble fraction elicited virus-neutralizing (1:1,200), complement-fixing (1:16), and hemagglutinating-inhibiting (1:80 to 1:160) antibody titers and were completely protected against monkey pox virus-induced disease. This model of monkey pox virus subunit vaccine preparation may prove to be useful in developing an efficacious noninfectious vaccinia vaccine for use in high-risk individuals.


Epstein-Barr virus viral capsid antigen titer by immunofluorescence with microplates: new semiautomated method based on the microtiter system. A semiautomated method of an indirect immunofluorescence technique for the titration of antibodies directed against viral capsid antigens of Epstein-Barr virus has been developed with Microtiter system units. By this method, a technician is able to titrate some hundred samples daily. The technique is safe, easy, and reproducible. The various procedures are described, and the sensitivity of the test is discussed.


Solid-phase radioimmunoassay for detecting bovine (neonatal calf diarrhea) rotavirus antibody. An indirect solid-phase microradioimmunoassay is described for detecting antibodies against rotaviruses. The test involved ethanol fixation of microcultures of bovine rotavirus-infected BSC-1 cells and reacetion with bovine antirotavirus serum, followed by 125I-labeled rabbit anti-bovine immunoglobulin G. The technique was shown to be virus specific and highly sensitive. The fixed microcultures could be stored at 4 degrees C for at least 2 months without affecting the sensitivity of the test. The application of this system for the detection of rotavirus antibodies in humans is briefly discussed.


Metabolic effects of diphosphonate in primary hyperparathyroidism. Six patients with primary hyperparathyroidism (PHPT) and one with squamous cell carcinoma of the esophagus with parathyroid hormone excess received disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) at a daily dose of 20 mg/kg orally. During treatment, the decrease in urinary calcium, total urinary hydroxyproline, and fasting urinary calcium suggested an inhibition of bone resorption. Serum calcium intestinal absorption of calcium and urinary cyclic adenosine monophosphate (cAMP) did not change significantly. This preliminary study indicates a possible role of diphosphonates in the management of inoperable cases of primary hyperparathyroidism or pseudohyperparathyroidism.


Effects of parathyroid hormone on cyclic AMP, cyclic GMP, and efflux of calcium in isolated renal tubules. The effects of parathyroid hormone (PTH) on concentrations of cyclic AMP and cyclic GMP were investigated in isolated renal cortical tubules from hamsters. Efflux of 45Ca from tubules was compared to temporal changes in both cyclic nucleotide concentrations. A rapid increase in cyclic AMP occurred following addition of PTH which was maximal by 1 min but decreased over the next 4 min period. Cyclic GMP concentrations were not significantly altered at 1 min but increased between 1 and 5 min from basal levels. Concentrations of both nucleotides remained significantly elevated from basal levels between 5 and 15 min following PTH. Efflux of 45Ca was increased by PTH with time-course changes closely paralleling changes in cyclic GMP concentrations. Changes in both cyclic AMP and cyclic GMP were related to PTH concentrations of the incubation media and were increased by addition of theophylline. Increasing the calcium concentration from 1 to 3 mM did not significantly alter the effect of PTH on cyclic AMP, however, cyclic GMP concentrations were further increased.


Characterization of a spectrophotometric assay for cAMP phosphodiesterase. The hydrolysis of cAMP can be monitored spectrophotometrically through the conversion of 5' AMP to 5' IMP using a specific 5' AMP amino-hydrolase (EC3.5.4.6). The optical properties and extinction coefficient differences of these compounds have been quantitatively determined. Phosphodiesterase assayed in this manner is linear with respect to time and enzyme concentration, and is more reliable than conventional assay procedures. Due to the high specificity of the assay system phosphodiesterase can be selectively assayed in unfractionated cytosol. The assay, when conducted on a conventional spectrophotometer, can detect the hydrolysis of 0.5 nmoles cAMP per min.


Evidence for differences in protein kinase modulator and and phosphodiesterase activator. Both protein kinase modulator and phosphodiesterase activator activities were present in the supernatant fluid of a homogenate of bovine brain. These were separated on a DEAE-cellulose column chromatography. Separation was also achieved by an isoelectrofocusing fractionation of the supernatant fluid, isoelectric points of proteins kinase modulator and phospodiesterase activator being 4.25 and 4.44, respectively. Phospodiesterase activator was purified from bovine brain to an apparent homogenity by a procedure which did not involve a drastic treatment such as boiling. The purification of phosphodiesterase activator resulted in removing the protein kinase modulator activity and the ratio of the activity of protein kinase modulator to that of phosphodiesterase activator in the sample decreased as the purification proceeded.


H2-histaminergic activity of clonidine in the guinea pig heart. Clonidine perfusion (1 muM) or injection (9.4 to 150.4 nmoles) into the isolated perfused guinea pig heart caused an increase in contractile force, phosphorylase a and cyclic adenosine monophosphate (cyclic AMP)  levels. The effects of clonidine were blocked by burimamide (30 muM). Proranolol (1 muM), phentolamine (1 muM) or reserpine treatment (5 mg/kg i.p., 24 hours prior to the experiment) did not influence the cardiac effects of clonidine. Clonidine (0.1 - 100 muM) also produced a dose dependent positive inotropic effect on right ventricle strips but had a negative chronotropic effect on the spontaneously beating right atria at higher concentration (0.1 to 1.0 M). Burimamide did not block the clonidine-induced negative chronotropic effect. Clonidine did not increase contractile force in guinea pig left atria. It also did not influence the isoproterenol-and phenylephrine-induced increases in cardiac force of contraction but did antagonize the positive inotropic effect of 4-methylhistamine in the right ventricle. This observation suggests that clonidine may compete with 4-methylhistamine for the same receptor sites. The results indicate that the cardiac receptors for both biochemical and mechanical effects of clonidine are histamine receptors of the H2-type.


Impaired monosynaptic potentiation in in vitro hippocampal slices from aged, memory-deficient rats. Neurophysiological experiments were conducted in vitro on 400 mu thick transverse hippocampal slices from aged and young rats. These slices exhibit neurophysiological responses similar to those of intact hippocampus. The aged rats have previously been found to exhibit impaired retention. Synaptic responses of the Schaffer collateral system were not found to be different between aged and young slices when elicited by very low frequency (0.3 Hz) electrical stimulation. However, the aged slices exhibited marked deficits in frequency and posttetanic potentiation in response to repetitive stimulation (15 Hz). This deficit was interpreted as resulting from an increased tendency to synaptic depression, rather than from impaired potentiation processes. The possibility of a relationship of these physiological deficits in hippocampal synaptic plasticity to the deficits in behavioral plasticity found in these aged animals is considered.


[Chemotherapy in placental tumors].

[Chemotherapy in placental tumors]. Chemotherapy is a useful element, but not the only element, for controlling placental tumours. In cases of simple mole routine chemotherapy does not seem to be justified and usually, in 9 cases out of 10, it is useless. It is certainly not always effective and sometimes it may even be dangerous because of the development of chemoresistance. Invasive mole and tumours where a histological diagnosis has not been made and where there is no particularly unfavourable prognosis, usually heal with twice weekly methotrexate carried on for two months after cure has been confirmed clinically, radiologically and biologically. Choriocarcinomata and cases where histology has not been carried out but which have poor prognosis (extra-pulmonary metastases, numerous or large pulmonary metastases, long delay in treatment and the excretion of high levels of HCG) justify chemotherapy in which vincristine is followed by methotrexate or vincristine is followed by actinomycine D. For cure in these bad cases secondary surgery to remove residual lesions, either in the uterus or the lungs, may be necessary.


Enhancement of the PGE1 response of macrophages by concanavalin A and colchicine. The effect of concanavalin A (Con A) and colchicine on the prostaglandin E1 (PGE1)-mediated cyclic AMP generation in rat peritoneal macrophages have been studied. Although Con A and colchicine by themselves did not affect cyclic AMP levels, they greatly enhanced cyclic AMP production induced by PGE1. There was not only augmentation of cyclic AMP levels at maximally active concentrations of PGE1, but also an increased sensitivity to low (inactive) concentrations of PGE1. Except for lentil lectin, none of the other lectins affected PGE1 sensitivity whereas lumicolchicine was as effective as colchicine. In addition, both Con A and colchicine raised the sensitivity to isoproterenol and choleraenterotoxin. Although details of the mechanisms by which Con A or colchicine influenced the membrane-bound adenyl cyclase and PGE1 receptors remain unclear, these observations suggest that certain alterations of the cell membrane may render macrophages more susceptible to the regulating effects of prostaglandins.


Epidermal adenylate cyclase systems: the retention of hormone responsiveness after enzymatic separation of pure epidermis. Although it has been shown that keratome-sliced skin contains active adenylate cyclase systems which respond to various hormones and drugs, unequivocal proof that the epidermis contains these hormone-responsive systems is still lacking. We demonstrate in this study that "pure" epidermis obtained after either collagenase or trypsin treatment does contain the hormone-sensitive adenylate cyclase systems.


Infection of the central nervous system produced by mixtures of defective-interfering particles and wild-type vesicular stomatitis virus in mice. In contrast to wild-type vesicular stomatitis virus (VSV), which produces a fulminant illness with death in two to three days, mixtures of homologous defective autointerfering (DI) particles and wild-type VSV (DI-wild-type VSV) injected intracerebrally into mice resulted in a slowly progressive disease of the central nervous system (CNS). In fact, mice inoculated with DI-wild-type VSV survived up to nine days after infection and displayed striking paralysis of the hind limbs. The slowly progressive CNS disease accompanying infection with DI-wild-type VSV was characterized by production of only 1% of the amount of VSV recovered when wild-type VSV was injected alone. Morphologically, mice infected with DI-wild-type VSV displayed a spectrum of pathologic changes not encountered with disease due to wild-type VSV alone. These changes included the presence of parenchymal necrosis in the spinal cord, changes in and secondary demyelination of the white matter, striking leptomeningeal inflammation, and spongiform changes in the gray matter of the neuropil. Since these pathological features are not found when CNS disease results from either wild-type VSV or temperature-sensitive (ts) mutants of VSV, it is suggested that CNS infection with ts VSV is not mediated principally by production of DI particles. Furthermore, in vivo CNS infection with DI-wild-type VSV did not appear to be mediated by production of ts VSV mutants.


In vivo investigation of antibacterial ointments. The clinically used topical antibiotic ointments, gentamicin 0.1%, oxytetracycline 3% w/polymyxin 0.1% and chloramphenicol 2% and an experimental preparation, 10-undecen-1-yl thiopseudourea iodide (AHR-1911) were studied for anti-infective action applied externally on the skin of mice inoculated subcutaneously with S. aureus and E. coli. In both infections statistically significant difference was encountered between curative and "clinical" healing rate in the case of the less effective preparations and/or dosages. The method appears suitable to establish and to compare the in vivo activity of ointments. This is not directly related to that of the aqueous drug solutions. AHR-1911, a powerful inhibitor of nucleic acid and protein synthesis, showed a bimodal action, with maximal effectiveness at 0.12-0.25% concentration, due presumably to the anti-inflammatory effect of higher concentrations. Direct evidence for the absorption of the drug from the application site was obtained using 14C labeled AHR-1911.


Inhibition of maturation and metabolism in rat oocytes by cyclic amp. It is known that dibutyryl cyclic AMP (dbcAMP) and theophylline inhibit the spontaneous maturation of isolated mouse oocytes. The present study demonstrates that dbcAMP (0.01-1.0 mM) as well as cyclic AMP (cAMP, 10 mM) and a phosphodiesterase inhibitor (IBMX, 0.01-1.0 mM) prevent spontaneous maturation of isolated rat oocytes. As reported earlier an increase in oxygen consumption by the oocyte was found following maturation. When the oocytes were cultured in the presence of dbcAMP or cAMP no change in respiration occurred during culture. These results argue against the theory that cAMP acts as a direct mediator of the action of luteinizing hormone (LH) on oocyte maturation. Furthermore they suggest that changes in oocyte energy metabolism are closely related to the maturation process.


An extended genetic recombination map for foot-and-mouth diseases virus. The original foot-and-mouth diseases virus recombination map (Lake, Priston & Slade, 1975), which include 35 mutagen-induced ts mutants, has been extended both in detail and size by the mapping of a further 33 ts mutants (9 mutagen-induced and 24 spontaneous). The size increase from 0.57% to 3.27% maximum recombination fequency was principally due to the use of a new standardization technique for recombination fequencies but, in addition, the original map distance was increased by approx. 30% due to the mapping of new mutations. As in the original map, there was a marked concentration of mutations near the guanidine (gs) locus, i.e. 83% of the mutants had mutations in the third of the map adjacent to the gs locus.


Simian virus 40-Chinese hamster kidney cell interaction. III. Characteristics of chemical induction in a clone of virogenic transformed cells. A number of chemical and physical agents were screened to determine their effectiveness in inducing simian virus (SV40) production in a virogenic clone of SV40-transformed Chinese hamster cells. Mitomycin C (MC) was the most effective inducing agent, and MC induction was further characterized. It was found that levels of infectious SV40 DNA were increased above control levels as early as 6 h after addition of MC to the culture medium and reached maximum levels by 48 h. Virus capsid (V) antigen and virions followed with a lag of about 24 h. V antigen production was sensitive to hydroxyurea, suggesting a dependence on virus DNA synthesis. The proportion of virus-producing cells (infectious centres) and the virus burst per cell were both stimulated by MC. Studies of 3H-thmidine incorporation demonstrated that the rate of SV40 DNA synthesis was maximal at 48 h post-induction, at which time cellular DNA synthesis was almost abolished. Caffeine, at doses not toxic to non-induced cells, strongly inhibited SV40production in both non-induced and induced cells, suggesting some role for DNA repair mechanisms.


Quantification of the herpes simplex virus DNA present in biochemically transformed mouse cells and their revertants. Four cell lines biochemically transformed by u.v.-irradiated herpes simplex virus contain virus DNA fragments ranging from 3 to 22% of the HSV genome. Of five revertant clones selected for 3H-TdR or BrdUrd resistance, four had lost all detectable virus DNA while the fifth, selected for BrdUrd resistance, retained the entire virus fragment but there was a reduction of virus copies per cell from 5 to 1. Three 'supertransformed' revertant cell lines contained virus DNA fragments ranging from 12 to 28%. The number of virus DNA fragments per cell ranged from 1 to 5 and clearly indicated that a single copy of the virus thymidine kinase gene is adequate for biochemical transformation. The determination of the base composition of the transforming virus DNA fragment indicated that the transforming DNA has a base composition approximately the same as the HSV genome and does not constitute a low GC virus DNA region. Cross hybridization between HSV-1 transformed cells and HSV-2 DNA is very slight, indicating that the DNA found in clone 139 is not entirely composed of the HSV-1 and HSV-2 common sequences.


Simian virus 40-Chinese hamster kidney cell interaction. IV. Enhanced virus replication in infected cells upon treatment with mitomycin C. Chinese hamster kidney cells are semi-permissive to simian virus 40 (SV40). Exposure to mitomycin C (MC) of Chinese hamster kidney cells infected with SV40 DNA enhanced the yield of infectious virus 10- to 100-fold. This stimulation occurred whether the treatment was performed before or after infection. A simultaneous increase in the number of V antigen-synthesizing cells and virus-producing cells, as well as the virus burst size, was observed upon MC pretreatment, whereas the proportion of T antigen-synthesizing cells remained unchanged. MC pretreatment clearly stimulated virus DNA replication in SV40 virus-infected cells. Cells treated with MC exhibited an unbalanced growth pattern, with continuing protein synthesis in the absence of cell division and a markedly reduced ability to replicate the cellular DNA. These results suggest that MC enhances the permissiveness of Chinese hamster kidney cells by inducing the synthesis of a specific cellular factor(s) required for SV40 reproduction in Chinese hamster kidney cells.


Antiviral activity in the rabbit cornea of adenine arabinoside, Ara-A 5' monophosphate, and hypoxanthine arabinoside; and interactions with adenosine deaminase inhibitor. The multiple microtrephination technique was used in the rabbit cornea to compare the activity against herpes simplex virus (hsv) of adenine arabinoside (ara-A), ara-A 5'monophosphate (ara-AMP) and hypoxanthine arabinoside (ara-Hx), and to determine the effect of addition of adenosine deaminase inhibitor (ADAI) to each. The greatest antiviral activity was shown by ara-AMP, and the least by ara-Hx. ADAI increased the activity of ara-A but had no effect on ara-AMP or ara-Hx.


Electrical and mechanical responses in the platysma and in the adductor pollicis muscle: in patients with myasthenia gravis. Electrical and mechanical muscular responses to single and repetitive stimuli were recorded in 24 patients with myasthenia gravis. Findings in the platysma were compared with those in m. adductor pollicis (ADP). In the platysma, but not in the ADP, electrical and mechanical responses to single stimuli were often lower than normal, and could be normalised after tetanus and by endrophonium. The decrement of electrical and mechanical responses to repetitive stimuli was two to three times greater in the platysma than in the ADP; post-tetanic facilitation of the action potential was four times greater. The staircase phenomenon was abnormal in the platysma in patients with moderate and severe myasthenia, and also in the ADP in some patients without decrement in the action potential. Edrophonium was more effective in alleviating decrement in the platysma than in the ADP. In the platysma, block of neuromuscular transmission could account for most abnormalities. The finding in some patients of an abnormal staircase after correction for block of fibres indicates a lesion in excitation-contraction coupling. In six patients only the platysma showed abnormalities, in 10 patients abnormalities were more pronounced in the platysma than in the ADP, and in three patients more pronounced in the ADP than in the platysma; in five patients the platysma and the ADP were equally affected.


Value of exchangeable electrolyte measurement in the treatment of myasthenia gravis. We have investigated electrolyte exchange in myasthenia gravis before and after corticotrophin therapy, using a four-isotope dilution technique. Clinical deterioration in patients on corticotrophin is associated with a fall of more than 20% in the intracellular potassium concentration, suggesting that all myasthenics so treated should be given potassium supplementation.


Post-ischaemic paraesthesia in pellagrins. A quantitative assessment of post-ischaemic paraesthesiae has been made in 50 pellagrins and 20 healthy identical controls. The results show a higly significant diminution of the paraesthetic response in pellagrins. In pellagrins having peripheral neuropathy the depression of paraesthesiae was more marked than in those without peripheral neuropathy. There was no consistent relationship between severity of peripheral neuropathy and degree of depression of paraesthetic response.


Peripheral neuropathy following a single exposure to arsenic. Clincal course in four patients with electrophysiological and histological studies. Four patients are described who developed a peripheral neuropathy 10 days to 3 weeks after ingestion of a single dose of arsenic. All improved slowly, but after 6 to 8 years 3 of them still had abnormal neurological symptoms and signs. Electrophysiological studies showed reduction of motor conduction velocity and marked abnormalities of sensory nerve action potentials. The findings suggest that conduction is abnormal in at least some surviving nerve fibres. Sural nerve biopsies from 2 patients showed axonal degeneration, which was at an early stage in some fibres, even 10 weeks after intoxication.


Ultrastructural effects of herpes simplex virus type 2 infection of rat dorsal root ganglia in culture. The ultrastructural consequences of herpes simplex virus type 2 (strain R-2) infection of organotypic cultures of embryonic rat dorsal root ganglia were studied. The intial consequences (dilation of endoplasmic reticulum and/or Golgi apparatus and distortion of mitochondrial structure) occurred in the cytoplasm. These effects were followed by several nuclear changes including loss of nucleoplasm, and margination of chromatin. Extensive nuclear membrane proliferation was accompanied by the viral maturation process. Two previously unreported observations were made. First, productive virus replications occurred in glial cells, as well as in neurons. Mature, enveloped virus was produced by nuclear budding and envelopment in the cytoplasm in both cell types. Second, neurons were observed to participate in polykaryocyte formation with other neurons and with glial cells. These polykaryocytes were usually composed of only three or four cells. Neuronal-glial polykaryocytes were more prevalent than neuronal-neuronal polykaryocytes. In general, however, the ultrastructural changes in neurons and glial cells in culture were consistent with previously reported changes occurring in nervous tissue of experimental animals suffering from acute herpes simplex virus infections. Therefore, the utilization of this in vitro system to further study the pathogenesis of acute herpetic infections of sensory ganglia appears to be reasonable.


Ultrastructural findings of peripheral nerve in a preclinical case of adult metachromatic leukodystrophy. In a 13-year-old neurologically healthy boy from a family with adult-onset of metachromatic leukodystrophy (MLD) showing arylsulfatase A-deficiency in the adult, sural nerve biopsy probably was performed 2-3 decades before clinical manifestation of the disease could be expected. Ultrastructurally 4 basic types of inclusion bodies in Schwann cells could be demonstrated (pleo-morphic "zebra body"-like inclusions, double-lamellated inclusions, "tuff-stone"-like inclusions, granular osmiophilic inclusions). Additionally, endoplasmatic reticulum, mitochondria and lysosomes showed marked alterations. Advanced damage of myelin was only rarely seen, but initial segmental demyelination was a common finding. These early pathological changes in chronic MLD are thought to represent a subcellular metabolic insufficiency of Schwann cells in this disease.


Spontaneous slow potentials and spreading depression in amphibian retina. 1. In frog and mudpuppy eye cups perfused with low-chloride solution, two types of slow potential phenomena were studied. One type, "spontaneous slow potentials" (SSPs), appeared both in the dark and during light stimuli. The other type, the slow potential change (SPC) of spreading depression (SD), appeared at termination of long-duration light stimuli. 2. The SSPs were analyzed by depth-profile studies, pharmacologic studies, and the use of potassium-specific electrodes. Results indicated that SSPs may represent spontaneous d-waves that travel across the retina. The SSPs are associated with potassium activity, and the main response is probably generated by Müller cells. Initiation and/or propagation appear to require chemically mediated synaptic transmission and impulse activity. 3. Depth-profile studies were also done of the SPC of SD induced by termination of long-duration light stimuli. Results indicated that the SPC is not an exaggerated d-wave. The SPC consists of two components, the second of which reverses more superficially than the d-wave. The main SPC response is probably generated by Müller cells. Although impulse activity does not appear to be necessary for SD, it may contribute to this complex response.


Neuromuscular transmission in dystrophic mice. 1. Neuromuscular transmission was studied in the extensor digitorum-longus muscle of dystrophic mice (strain 129/ReJ) by means of intracellular recording techniques. 2. In a large population of normal and dystrophic muscle fibers tested, the incidence of transmission failure was about 2% and showed no significant difference between the two groups. 3. Quantal size and quantum content of dystrophic junctions were found to be normal. This was true even of nerve terminal on apparently atrophied muscle fibers. 4. The facilitation ratio at dystrophic junctions was not significantly different from normal. 5. Dystrophic neuromuscular junctions exhibited an abnormality high frequency of giant spontaneous potentials. Application of tetrodotoxin (10(-6) M) and curare (10(-6) M) indicated that these potentials were caused by impulse-independent release of acetylcholine. 6. Neuromuscular transmission in dystrophic mice was found functionally normal and unrelated to the degenerative state of the muscle.


Effect of high-oleic and high-linoleic safflower oils on mammary tumors induced in rats by 7,12-dimethylbenz(alpha)anthracene. A mutant safflower oil, rich in oleic acid, was used for a critical test of the hypothesis that polyunsaturated fats act as co-carcinogens. Weanling female rats were each given 5 mg of 7,12-dimethylbenz(alpha)anthracene. They were then pair-fed diets containing 20%, by weight, of conventional high-linoleic safflower oil; a mutant high-oleic safflower oil; or coconut oil. Half of each group received supplementary DL-alpha-tocopherol. Tumors were identified by two observers, by palpation. Data on incidence of tumors and on numbers of tumors per affected rat led to similar conclusions. At 16 weeks, there were significant differences when supplementary tocopherol was included in the diet: the group fed high-oleic safflower oil had more tumors than the group fed coconut oil. This difference was not seen in the absence of supplementary tocopherol. When the data for tocopherol-supplemented and unsupplemented subgroups were combined, the high-oleic safflower oil group had significantly more tumors than did the coconut oil group. The high-linoleic safflower oil group was not significantly different from either of the other groups. In all groups, histologic examination of the largest tumor in each rat revealed more benign tumors, mostly duct papillomas, than carcinomas.


Phagocytosis and leukocyte enzymes in ascorbic acid deficient guinea pigs. Enzymes related to bactericidal activities of leukocytes were studied in ascorbic acid deficient guinea pig leukocytes. The activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were not affected either under resting or phagocytizing conditions in ascorbic acid deficiency. Granule bound NADPH-oxidase activity of resting leukocytes also was not altered in ascorbic acid deficiency. However, the extent of stimulation in NADPH-oxidase activity under phagocytizing condition was found to be significantly lower in ascorbic acid deficient leukocytes than that in control leukocytes. Similary, the extent of release of acid phosphatase from lysosomes during phagocytosis was also low in ascorbic acid deficient leukocytes. Ascorbic acid deficiency did not influence the activities of glutathione reductase and myeloperoxidase of leukocytes. The significance of these enzyme changes is discussed in relation to the decreased phagocytic and bactericidal activities of leukocytes in ascorbic acid deficiency.


Altered enzyme release by virus infected mouse salivary glands. The rates of release of salivary amylase and esterase from normal and polyoma virus infected mouse submandibular glands were measured in a continuous flow perifusion system. Following stimulation by epinephrine, the rate of release of esterase by the infected glands was significantly greater than that from control glands. The rate of amylase release, while greater from infected glands, was not significantly different. The total enzyme contents from infected and control tissues were similar. Cyclic GMP was found to be higher in the infected glands than the control glands, suggesting one possible mechanism for the higher rates of enzyme release by infected tissues.