The role of 1 alpha, 25-dihydroxyvitamin D in the mediation of intestinal hyperabsorption of calcium in primary hyperparathyroidism and absorptive hypercalciuria. The cuase for the intestinal hyperabsorptionof calcium (Ca) in various forms of hypercalciurias was explored by a careful measurement of plasma 1 alpha, 25-dihydroxycholecalciferol [1 alpha, 25-(OH)I D] and by an assessment of intestinal Ca absorption and of parathyroid function. In 18 cases of primary hyperparathyroidism (PHPT), the mean plasma concentration of 1 alpha, 25-(OH)2D was significantly increased (4.9 +/- 2.2 SD ng/dl vs. 3.4 +/- 0.9 ng/dl for the control group), and was significantly correlated with fractional Ca absorption (alpha) (r = 0.80, P less than 0.001). Plasma 1 alpha, 25-(OH)2D was also correlated with urinary Ca (P less than 0.05), but not with serum Ca or phosphorus (P), P clearance, urinary cyclic AMP, or serum immunoreactive parathyroid hormone. In 21 cases of absorptive hypercalciuria (AH), plasma 1 alpha, 25-(OH)2D was elevated in one-third of cases, and the mean value of 4.5 +/- 1.1 ng/dl was significantly higher than that of the control group (P less than 0.01). Since relative hypoparathyroidism may be present, the normal absolute value of plasma 1 alpha, 25-(OH)2D, found in two-thirds of cases of AH, may be considered to be inappropriately high. Moreover, in the majority of cases of AH, the data points relating plasma 1 alpha, 25-(OH)2D and alpha fell within 95% confidence limits of values found in non-AH groups (including PHPT). The results suggest that the intestinal hyperabsorption of Ca in PHPT aw AH may be vitamin D dependent. However, the disturbance in vitamin D metabolism may not be the sole cause for the high Ca absorption in AH, since in some patients with AH, the intestinal Ca absorption appears to be inapp


Stimulation of hepatic sodium and potassium-activated adenosine triphosphatase activity by phenobarbital. Its possible role in regulation of bile flow. Since phenobarbital administration produces a profound increase in bile flow without changing bile acid secretion, we examined whether this drug increases the activity of hepatic sodium-potassium-activated ATPase [Na+-K+)-ATPase], the postulated regulating enzyme in the secretion of bile salt independent bile flow. After freeze-thawing to increase substrate accessibility, (Na+-K+) ATPase activity was determined by ouabain inhibition of total ATPase activity. Its activity was highest in isolated liver surface membrane fractions enriched in bile canalicult. Phenobarbital administration significatly increased (Na+-K+)-ATPase activity in both liver surface membrane fractions as well as liver homogenates. This enhanced activity is apparently selective for other membrane phosphatases and the enzyme activity in other tissues is either unaltered or decreased. Kinetic analysis of (Ka+-K+)-ATPase indicates that phenobarbital treatment increased maximum velocity and half-maximum activation constant was unchanged, consistent with activation of latent molecules or an increased number of enzyme molecules. The latter process seems more likely because cycloheximide prevented phenobarbital induction and activators were not demonstrated in vitro. Examination of the full time course of phenobarbital induction to determine whether phenobarbital increased synthesis or decreased degradation was consistent with increased synthesis since the apparent degradation rates were similar with or without phenobarbital treatment. The apparent half-life for (Na+-K+)-ATPase was estimated to be approximately 2.5 days, consistent with liver surface membrane protein turnover. The correlation of changes in bile flow with (Na+-K+)-ATPase was examined under several experimental situations. Phenobarbital caused a parallel increase in each during the 1st 2 days of greatment: thereafter other factors become rate limiting for flow, since enzyme activity doesn't reach a new steady state until 4-days. Consistent with increased sodium-potassium exchange, bile sodium was unchanged while potasium concentrations were significantly reduced. Changes in both bile flow and (Na+-K+)-ATPase induced by phenobarbital are independent of thyroid hormone. These studies support the postulate that (Na+-K+)-ATPase is an important factor in regulation of bile flow. In addition, phenobarbital enhancement of both bile flow and (Na+-K+)-ATPase is dependent upon de novo protein synthesis.


Effects of levamisole on normal and abnormal leukocyte locomotion. The anti-helminthic drug levamisole hydrochloride has been reported to stimulate immune responses in humans and experimental animals. We have investigated levamisole effects on human leukocyte locomotion in vitro in studies of neutrophils and mononuclear cells from normal adults, from patients with Chediak-Higashi disease and from patients with the syndrome of hyperimmunoglobulin E, recurrent pyogenic infections, and defective leukocyte chemotaxis. Directed migration (chemotaxis) of neutrophils and mononuclear cells from normal adults and from the hyperimmunoglobulin E syndrome patients, but not from Chediak-Higashi patients, were stimulated by levamisole at concentrations of 0.01-1.0 micronM, with stimulation observed most consistently at 0.1 micronM. These concentrations of drug also increased cyclic GMP levels in mononuclear cells and enhanced hexose monophosphate shunt activity in neutrophils, but did not alter chemotactic factor-induced changes in the surface charge of neutrophils. Other concentrations of levamisole did not affect leukocyte locomotion except for a high concentration (5.0 mM) which stimulated both random and directed leukocyte migration. When patients with the hyperimmunoglobulin E syndrome took levamisole by mouth, the abnormal chemotactic responses of their neutrophils were significantly improved towards normal. These studies are the first to show pharmacologic improvement of in vitro leukocyte locomotion in patients in whom recurrent infections have been attributed to a defect of this leukocyte function.


Enhancement of platelet function by superoxide anion. During the aerobic conversion of xanthine to uric acid by xanthine oxidase, superoxide anion and hydrogen peroxide are produced along with the hydroxyl radical. Our studies demonstrate that washed human platelets incubated with xanthine and xanthine oxidase aggregated and released [14C]serotonin. Aggregation and release were dependent on the duration of exposure to xanthine oxidase as well as the concentration of enzyme. Both reactions were inhibited by the superoxide scavenger enzyme superoxide dismutase but not by catalase, or the free radical scavenger mannitol, suggesting that they were induced by superoxide anion. Superoxide-dependent release was inhibited by prior incubation of platelets with 1 mM EDTA, 1 micronM prostaglandin E1, or 1 mM dibutyryl cyclic AMP, but was unaffected by 1 mM acetylsalicylic acid or 1 micronM indomethacin. After prolonged incubation with xanthine and xanthine oxidase there was also efflux of up to 15% of intraplatelet 51Cr, a cytosol marker. This leakage was prevented by the addition of catalase to the media but not by superoxide dismutase. Incubation with xanthine and xanthine oxidase did not produce malonyldialdehyde, the three-carbon fatty acid fragment produced during prostaglandin endoperoxide synthesis and lipid peroxidation. Prior exposure of platelets to low fluxes of superoxide anion lowered the threshold for release by subsequent addition of thrombin, suggesting a synergistic effect. We conclude that superoxide-dependent aggregation and release may be a physiologically important method to modulate hemostatic reactions particularly in areas of inflammation or vessel injury which could have high local concentrations of superoxide anion.


Antiproliferative effects of 9-beta-d-arabinofuranosyladenine in a mammalian cell line devoid of adenosine deaminase activity. The effect of ara-A on cellular growth, DNA synthesis, and RNA synthesis, and RNA synthesis was measured in an established cell line (B-mix K-44/6) devoid of adenosine deaminase activity. Cells adapted to growth in a medium supplemented with horse serum provided an environment totally lacking adenosine deaminase activity whereas cultivation of cells in a medium supplemented with calf serum provided a system capable of deaminating ara-A to ara-H (half-life = 14 hours). Under deaminase-free conditions early log phase cells underwent 1.5 population doublings during 28 hours compared with 0.25 doublings in the presence of 37 micronM ara-A. When cells were grown in medium supplemented with calf serum the additionof 37 to 225 micronM ara-A resulted in a cessation of mitosis for periods of 5 to 30 hours respectively. Following this quiescent period growth resumed at the original rate. With 600 micronM ara-A mitosis was reversibly inhibited up to 35 hours after drug addition. The effects of ara-A on RNA and DNA synthesis were monitored by continuously or pulse labeling B-mix K-44/6 cells with [3H]-uridine or [3H]thymidine. Ara-A did not influence RNA synthesis as judged by labeled uridine incorporation. Under deaminase-free conditions, 5.4 micronM ara-A inhibited labeled thymidine incorporation by 50%. In the presence of the enzyme, approximately twice the ara-A concentration was required for the same inhibition; furthermore the initial inhibition was followed by a partial recovery in the rate of thymidine incorporation. Examination of thymidine incorporation. Examination of thymidine nucleotide pools during ara-A treatment revealed to changes in the labeling of dTMP, dTDP, and dTTP. Thus inhibition of [3H]thymidine incorporation by ara-A accurately reflected inhibition of DNA synthesis. We conclude that, in spite of an initial inhibition of DNA synthesis and mitosis by ara-A, B-mix K-44/6 cells recover from the inhibitory effects if the drug is removed either by a change in the culture medium or by metabolism to ara-H.


Correlation between increased bronchial responsiveness to histamine and diminished plasma cyclic adenosine monophosphate response after epinephrine in asthmatic children. Diminished plasma cyclic adenosine monophosphate response after epinephrine in moderate childhood asthma. The respiratory threshold to histamine and the plasma cyclic adenosine monophosphate (AMP) every 5 min for 40 min after subcutaneous epinephrine were determined in 21 children with moderate bronchial asthma who were without symptoms at the time of study. There was a statistically significant correlation between a high respiratory sensitivity to histamine and a low plasma cyclic AMP response to epinephrine. The plasma cyclic AMP response was compared with that in 16 control subjects. The asthmatic patients had significantly diminished responses; the difference was greatest for the values 25 min after stimulation. This study supports the hypotheses that the bronchial hyperresponsiveness in asthma is due partly to a defective beta adrenergic system and that the defect is permanent, existing also during periods without symptoms or medication and in patients with moderate asthma.


Comparison of cyclic adenosine monophosphate response of lymphocytes in normal and asthmatic subjects to norepinephrine and salbutamol. Reduced response of beta adrenergic receptors, especially beta-2 receptors, has been suggested as a contributing factor in the etiology of asthma. Cyclic adenosine monophosphate (AMP) production in lymphocytes after exposure to 10(-3) M salbutamol, predominantly a beta-2 receptor stimulant, was significantly less in asthmatic subjects than in normal subjects, while there was no significant difference in cyclic AMP response to 10(-3) M norepinephrine, predominantly a beta-1 receptor stimulant. Both drugs evoked the maximum response at 10(-3) M. The cyclic AMP response to salbutamol of 5 asthmatic subjects being treated with steroids was diminished significantly compared with that of 7 patients not treated with steroids; however, the response to norepinephrine was similar in both groups. The degree of the abnormality in the beta-2 receptor response seems to be related to the severity of the asthma.


Subsensitivity of beta responses during therapy with a long-acting beta-2 preparation. The question whether some tolerance or subsensitivity of various beta receptors develops during therapy with long-acting oral beta-2 agents has practical and theoretical importance. We applied a strong beta-2 stimulus (terbutaline, 5.0 mg orally) at weekly intervals for up to three weeks in 19 stable asthmatics and bronchitics while commencing 5.0 mg terbutaline three times daily. The evening dose was omitted before each morning challenge. Challenges were continued at one and two weeks off terbutaline in some patients to test return of beta function. Patients received no ephedrine for two weeks before the study but were allowed aminophylline or isoproterenol inhalations up to 18 and 4 hr before challenges, respectively. Pulmonary function, pulse, and blood pressure were monitored at 0, 60, 120, and 180 min, and metabolic parameters measured at 0 and 180 min. There was significant drug tolerance in the drop and minimum diastolic pressure reached, rise in lactate, cyclic AMP, and blood glucose, and drop in eosinophils. Peak FEV1 and V50 dropped slightly, but vital capacity and minimal airway resistance did not change significantly. During continuous therapy this slight bronchial subsensitivity is probably obscured by elevated baseline function. It might assume importance during periods of excessive inhaler use or abrupt drug withdrawal.


Aortic medial calcification in progeria-like syndrome. Aortic medial calcification was investigated in rats in which the progeria-like syndrome (PLS) was evoked by administering dihydrotachysterol. In 35 experimental rats and 15 controls, calcification was studied morphologically by light and electron microscopy, and by enzyme histochemistry. Body weight, food intake and serum calcium levels were also determined. Calcification occurred along and on the elastic lamellae in association with the accumulation of ground substance. In the smooth-muscle cells surrounding the calcified foci, the activities of various lysosomal enzymes increased concomitantly with a tendency toward transformation of smooth-muscle cells to a modified form. From these observations, the role of ground-substance formation by smooth-muscle cells is postulated, and participation in the catabolism of ground substance by the lysosomal enzymes of these cells is suggested. It appears the increased activity of adenosine monophosphatase should be linked to the calcification. The etiology of weight loss, skin manifestations and aortic calcification in PLS rats seems to be different from that in human progeric diseases. Therefore, the PLS rat should not be readily accepted as an animal model for the study of progeric diseases.


Immunological study of cytomegalovirus complement-fixing antibodies in the population of the CSR. The population from different regions of the CSR was examined serologically for the presence of cytomegalovirus (CMV) antibodies. Exclusively persons showing no signs of disease, chosen by random selection, were examined. The immunological survey was carried out by the complement fixation reaction with CMV antigen prepared in the laboratory from the international strain AD 169. The high incidence found in normal population is suggestive of a considerable dispersion of cytomegalovirus infection. The contact with the virus is followed by antibody response, manifested in most cases only subclinically and asymptomatically. The incidence of CMV antibodies increases with increasing age. In young age groups, antibodies were found in approximately 20%. The number of persons showing positive reactions increased gradually and in the oldest age groups antibodies were found in 70%. The significance of factors causing the incidence of cytomegalovirus antibodies in the population is discussed.


Effect of concanavalin A on the killing of tumor cells by antibody and complement. Concanavalin A (Con A) was found to inhibit the killing of antibody-sensitized line-1 tumor cells (TA) by guinea pig complement (GPC) but not by human complement (HuC). Other plant lectins (wheat germ, leucoagglutinin, and pokeweed mitogen) were also tested but Con A was the only lectin found to inhibit antibody-GPC-mediated killing. The inhibitory effect of Con A was observed when the GPC was mixed with Con A or when the antibody-sensitized cells were pretreated with Con A (TA-Con A) before the addition of GPC. The effect could be reversed by treatment of such cells with alpha-D-methylglucopyranoside or by incubation at 37 degrees C for approximately 2 hr. Con A appeared to act by preventing the binding of the first component of GPC (GPC1) to antibody-sensitized tumor cells. Differences in the binding of the first component of HuC (HuC1) and GPC1 to TA-Con A suggested that a difference in the binding site for HuC1 and GPC1 might exist. There was no difference in the number of GPC1 molecules fixed to antibody-sensitized sheep erythrocytes (EA) or EA treated with Con A in experiments using the same antibody as used with the tumor cells and the same Con A preparation. It would consequently appear that the inhibitory effect of Con A on the binding of GPC1 to TA is not due solely to an interaction of Con A with the antibody.


Studies of viral antibody responses among Amish families. Serum antibodies to adenovirus (ADN), cytomegalovirus (CMV), herpes simplex virus (HSV), influenza (INF), para-influenza (PAR), mumps (MUM), coxsackie B4 (Cox B4) and B5 (Cox B5) viruses were measured from 584 individuals belonging to 21 Indiana Amish families. Sex and age effects on antibody responses to cytomegalovirus were observed. Age effect on CMV, HSV, INF, PAR, MUM responses were also found. The percentage of responders to some of the viruses was shown to be age dependent, but the levels of antibody response were not affected by the difference in age. A familial basis for the antibody response was demonstrated. Attempts at demonstrating association between HLA haplotypes and responses were not successful. The unlikelihood of predominantly HLA-associated control of viral antibody response was discussed.


The in vitro effects of histamine and metiamide on neutrophil motility and their relationship to intracellular cyclic nucleotide levels. Histamine at concentrations of 1 x 10(-5) M to 5 x 10(-5) M consistently increased neutrophil movement as measured in Boyden chambers. This effect was entirely caused by stimulation of chemokinesis (stimulated random migration) and true chemotaxis was inhibited by these concentrations. This inhibition of chemotaxis could be abolished by pretreatment with metiamide, an H-2 receptor antagonist, and levamisole, but not by diphenylhydramine, an H-1 receptor antagonist. Metiamide at similar concentrations produced a mild stimulation of chemokinesis but has no effect on true chemotaxis. The histamine effects on neutrophil motility were associated with increased levels of intracellular cAMP wehreas cAMP levels were unaffected. Agents known to elevate intracellular cAMP levels produced effects on neutrophil motility similar to those of histamine. It is suggested that histamine exerts a 2-fold effect on neutrophil motility mediated via an H-2 receptor site and associated with elevated levels of cAMP.


Induction of phenotypic lymphocyte differentiation in LPS unresponsive mice by an LPS-induced serum factor and by lipid A-associated protein. Spleen cells from C3H/HeJ mice are known to be unresponsive to mitogenic stimulation by LPS. We show here that T and B cell precursors of C3H/HeJ mice are unresponsive to induction of differentiation by LPS. Phenotypic differentiation of C3H/HeJ lymphocytes can be induced with DB-cAMP, Lipid A-associated protein, and with a serum factor induced by LPS in LPS responder strains.


Relationships between H-2 and viral antigens in murine oncornavirus-induced tumours. Cytolytic T lymphocytes (CTL) from murine sarcoma virus (MSV) or Friend leukaemia virus (FLV) inoculated mice lyse syngeneic much more efficiently than allogeneic FMRGi+ lymphoma cells. By comparing the cytolysis of various H-2 different 51Cr lymphomas by CTL from several inbred and congenic lines differing at H-2, and by competition experiments using unlabelled cells, one can demonstrate that this phenomenon is due to an H-2 barrier. H-2b/H-2d hybrid-anti-MSV-CTL immunized by H-2b, H-2d or H-2b/H-2d tumours lyse only FMRGi+ lymphomas of the same H-2, and their activity for a given target is inhibited only by H-2-identical competitive cells. H-2 antigens are therefore directly involved in the interaction between tumour cells and immune CTL which probably react with an 'H-2 modified' antigen of the tumour cells surface. The use of CTL from intra-H-2 recombinant lines shows that H-2D and probably H-2K molecules are involved, but vary according to the tumour cells. A possible role of the I region is discussed as well as the implications of these results in immunosurveillance against viral neoplasia.


Leukocyte and lymphocyte cyclic AMP responses in atopic eczema. Lymphocytes from subjects with mild and severe atopic eczema were compared with normal control subjects in regard to their cAMP (3';5'-cyclic adenosine monophosphate) responses to a variety of stimulatory agents. Individuals in the severe eczema group were shown to have a significant diminution in their unstimulated lymphocyte cAMP levels and absolute cAMP responses to 0.5 mM theophylline, 0.5 mM theophyline + 1 micronM epinephrine, 10 mM isoproternol, 1 mM isoproterenol, 10 mM salbutamol, and 3 micron M PGE1. Individuals with mild eczema had a reduced response to 0.5 mM theophylline. The severe eczema groups also differed in a number of these responses from a group of 5 subjects with severe psoriasis. Mixed leukocyte cAMP responses to 10 mM isoproterenol also were examined and found to be diminished in individuals with eczema.


Suppressed response to interferon inducation in mice infected with encephalomyocarditis virus, Semliki forest virus, influenza A2 virus, Herpesvirus hominis type 2, or murine cytomegalovirus. Mice infected with encephalomyocarditis virus, Semliki Forest virus, influenza A2 virus, Herpesvirus hominis type 2, or murine cytomegalovirus developed a state of hyporeactivity to interferon induction. In general, the capacity of infected animals to produce interferon in response to inducers became progressively impaired during the course of infection. The severity and time of onset of hyporeactivity, however, were dependent upon the inducer and the nature of the viral infection. During viral infections associated with generalized hyporesponsiveness, a factor that could inhibit interferon production by murine cells in culture was identified in the serum. This serum hyporeactive factor may have mediated the development of hyporeactivity in vivo. Hyporeactivity of the host's interferon response was associated with progression of viral infection and may be partially responsible for the limited effectiveness of interferon inducers in the modification of viral infections, when administered after onset of symptoms.


Genital Herpesvirus homonis infection in mice. II. Treatment with phosphonoacetic acid, adenine arabinoside, and adenine arabinoside 5'-monophosphate. Genital infection of mice with Herpesvirus hominis type 2 provides an experimental model for screening potential antiviral chemotherapeutic agents before clinical trials in humans. Intravaginal treatment with phosphonoacetic acid (at a dose of 500 mg/kg in saline or as a 5% cream) initiated 3 hr after inoculation with H. hominis type 2 completely inhibited viral replication in the genital tract and prevented subsequent mortality. Although therapy initiated 24-72 hr after infection significantly reduced titers of virus in vaginal secretions from three- to 100-fold, most mice eventually died of encephalitis. Topical treatment with either adenine arabinoside or adenine arabinoside 5'-monophosphate at a dose of 500 mg/kg in saline or as a 10% cream failed to alter viral replication in the genital tract or to protect the mice from death due to encephalitis. Treatment by the intraperitoneal route with any of these three agents had no effect on local viral replication or final mortality.


Clinical and pathogenetic studies of Medical Lake macaque virus infections in cynomolgus monkeys (simian varicella). The Medical Lake macaque (MLM) virus produced varicelliform eruptions in cynomolgus monkeys. Not all experimentally infected monkeys developed overt disease; viremia was found, and specific antibodies were detected. Specific lesions were found in skin, lymph nodes, and spleen. Focal inflammatory lesions were present in liver, pancreas, and lung (after intratracheal instillation of virus). MLM virus was recovered from these and other organs. The temporal movements of MLM virus in and out of primary and secondary target organs remained partially unsolved. MLM virus is related to the Wu strain of varicella virus.


A longitudinal study of varicella-zoster virus infections in renal transplant recipients. A serum bank maintained for renal transplant recipients allowed for a longitudinal study of antibody responses before and after herpes zoster. Renal transplant recipients without herpes zoster served as controls. Antibody responses to varicella-zoster virus, herpes simplex virus type 1, and cytomegalovirus were measured. The serological responses following herpes zoster were prompt and sustained (in the majority of cases), transient, or not present at all. Zoster without an eruption occurred (apparent only on retrospective chart review) and furnished an explanation for unexplained unilateral pain syndromes in these patients. Asymptomatic rises in titer of antibody to varicella-zoster virus not explained by rises in antibody to herpes simplex virus occurred in both groups. This latter finding points to an unstable relation between virus and host and supports and hypothesis of Hope-Simpson that subclinical release of virus with resulting antigenic stimulation may maintain immunity to varicella-zoster virus. Patients with herpes zoster and controls did not differ in several humoral immune parameters that might have explained the occurrence of herpes zoster. There was no evidence that herpes zoster precipitated renal graft rejection.


Cellular immune responses to herpesviruses during treatment with adenine arabinoside. Thirteen patients severely infected with herpesvirus were treated with intravenous adenine arabinoside (ara-A), and two patients received placebo therapy. Blastogenic and cytotoxic responses specific for the virus infecting each patient were determined before, during, and after treatment. Blastogenic responses to three mitogens (phytohemagglutinin, pokeweed, and concanavalin-A) were examined, as were titers of viral antibody. In vitro responses during and after treatment with ara-A were unchanged or often enhanced as compared with values before treatment. Newborn infants, presumably infected at or shortly before birth, did not demonstrate cellular immune reactivity to the infecting virus until after four days of life. In this series of patients, prognosis appeared to be in part determined by the cellular immune competence of the host at the time of infection.


Virological and serological studies of neurological complications of acute hemorrhagic conjunctivitis in Thailand. An extensive outbreak of acute hemorrhagic conjunctivitis (AHC) occurred from September to December 1974 in Thailand. At least 29 patients with polio-like motor paralysis that complicated AHC were hospitalized in Bangkok. Paired or triplicate samples of serum from 16 patients were tested for neutralizing antibody to enterovirus type 70 (EV70). A significant rise in titer of antibody was found for two patients, and the other 14 had neutralizing antibody titers ranging from 1:8 to 1:512 without an increasf larger than or equal to 1:16, a level which is considered to be diagnostically significant. Neutralizing antibody to EV70 was detected in 19S fractions of nine sera examined, but neutralizing antibody to three types of poliovirus was confined to 7S fractions. EV70 was isolated from one of seven stool specimens collected on day 37 after the onset of AHC and none of 10 samples of cerebrospinal fluid. These results and additional clinical and epidemiologic findings gave further support to the hypothesis that EV70 infection can cause polio-like motor paralysis as a complication of AHC.


Effect of immunization on acute and latent infections of vaginouterine tissue with herpes simplex virus types 1 and 2. Inoculation of mice with herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) by the vaginal route resulted in viral shedding during the acute phase of the infection and the development of a latent infection in vaginouterine tissue lasting up to one year in greater than 25% of the animals. Immunization with either serotype of HSV markedly reduced viral shedding when animals were subsequently challenged with the homologous serotype, but immunization with HSV-2 was significantly less effective in preventing the development of a latent infection in the vaginouterine tissue after challenge than was immunization with HSV-1.


Immunomodulation of host resistance to experimental viral infections in mice: effects of Corynebacterium acnes, Corynebacterium parvum, and Bacille calmette-guérin. Resistance to a representative group of experimental virual infections in mice was significantly enhanced by nonspecific modulation of host defense mechanisms. Corynebacterium acnes, Corynebacterium parvum, and bacille Calmette-Guérin were effective in enhancing host resistance. Animals treated seven to 10 days before inoculation of virus were protected against a lethal infection with Herpesvirus hominis type 2, encephalomyocarditis virus, murine cytomegalovirus, or Semliki Forest virus. The protection of experimental animals against encephalomyocarditis virus infection intitiated by either the intraperitoneal or the respiratory route indicated that C. acnes exerted a systemic, rather than local, effect. A maturation process was required for host defense mechanisms stimulated by C. acnes, as indicated by the failure to enhance resistance in suckling animals. Involvement of cells of the lymphoreticular system was demonstrated by transfer of enhanced resistance against H. hominis type 2 to recipient animals with peritoneal exudate cells harvested from mice pretreated with C. acnes. Finally, these same cells inhibited the progression of herpetic infection in tissue culture. The data suggest that immunomodulation, possibly through activation of macrophages, may offer a method for enhancement of host resistance to viral infections.


Slow virus infection: replication and mechanisms of persistence of visna virus in sheep. The influence of the age and immune status of the host on the slow replication and persistence of visna virus in sheep was studied. Twenty-five randomly bred fetal American lambs were inoculated intracerebrally with visna virus. Eight of these fetuses were immunosuppressed by thymectomy and antiserum to lymphocytes before inoculation. Fetuses were sacrificed sequentially, and tissues were processed for viral quantitation. No exponential increase of virus occurred in either the normal or immunosuppressed fetuses, and virus was recovered mainly by explanation of tissues. This finding indicated that the viral genome was present in tissue cells but that the extent of replication in the early phase of infection was restricted by factors unassociated with maturation or immune status of the host. In addition, virus isolated from the peripheral blood leukocytes of a sheep one year after inoculation was antigenically distinct from the plaque-purified virus used for inoculation. This distinction suggested that a major antigenic shift of the agent had occurred and provided another mechanism for the maintenance of the persistent infection.


Infection and fertilization of mice after artificial insemination with a mixture of sperm and murine cytomegalovirus. Female mice were artificially inseminated with a solution of sperm and cytomegalovirus (experimental) or sperm alone (control). Maternal infection was usually induced when virus accompanied sperm at insemination. Fertilization occurred in the presence of virus, and embryogenesis appeared normal on gross examination, although a slight reduction in the number of embryos was observed in the experimental group. Tissue cultures were prepared after gestation for 14 days from individual and pooled embryos. In one of 28 instances, virus was recovered from blind-passaged, experimental, embryonic fibroblasts. All control cultures were negative. This model may prove useful in further study of the pathogenesis of intrauterine cytomegalovirus infection.


Transmission and activation of cytomegalovirus with blood transfusion: a mouse model. A mouse model that mimics many features of human cytomegalovirus (CMV) infections associated with transfusion and perfusion is described. The concept of antigenic activation of CMV was tested by infusion of blood from latently infected mice, which were found to be virus-negative by tissue culture asssay, into uninfected allogeneic and isogenic hosts. After a latent period, virus was detectable invariably in allogeneic and only rarely in isogenic recipients. Transfusions from uninfected donors into latently infected mice activated CMV in heterologous and homologous recipients. These observations should assist in definition of relevant pathogenetic principles and may explain the failure to recover CMV from healthy human blood donors in spite of predictions of a carrier state based on epidemiologic observations.


Anaerobic bacteria in biliary disease in elderly patients. Gallbladder bile from 52 elderly subjects who had undergone biliary tract surgery was examined for the presence of bacteria. Twelve patients had sterile bile, 18 specimens of bile yielded anaerobes as well as aerobes, and 22 yielded aerobic bacteria only. Escherichia coli was the most commonly isolated organism (30 strains). Bacteroides fragilis was the most frequently encountered anaerobic bacterium and was found in 15 patients. The Klebsiella-Enterobacter group was the second most commonly isolated group and B. fragilis was third. Clostridium perfringens was recovered in 10 specimens of bile. Anaerobic bacteria were recovered more frequently in patients with ductal obstruction. The relatively frequent isolation of anaerobes, especially of B. fragilis, in this study may be related to the anaerobic techniques used, to the age of the patients, and to the high incidence of pigment stones among the subjects.


Aquanititave semimicro, semiautomated colorimetric assay for interferon. The colorimetric assay for interferon, which utilizes a vital dye uptake for determination of cell viability, was adapted for semimicro quantities of cells and reagents and semiautomated techinques. Factors affecting interferon titer included the duration if interferon treatment of cells prior to viral challenge, the multiplicity of viral challenge, and the number of viral replicative cycles. Only the multiplicity of the volume, of the interferon sample determined final titer, emphasizing that introduction of a volume term in a statement of interferon titer expresses interferon mass. The semimicroassay for interferon in both human and mouse cells proved precise, sensitive, convenient, reliable, and relatively simple and rapid.


Some experiments on the role of the foetal pituitary in the maturation of the foetal adrenal and the induction of parturition in sheep. The effect of repeated increases in plasma ACTH on the production of corticosteroids and androstenedione in the sheep foetus has been investigated. Elevation of foetal plasma ACTH for up to 2 h every 24 h by repeated periods of hypoxia increased the output of cortisol. No consistent effects on foetal or maternal androstenedione concentrations or on maternal oestrogen levels were observed. Repeated short periods of increased foetal plasma ACTH concentration may promote maturation of the foetal adrenal, but there is no increase in androgen secretion by the gland nor is there an increase in oestrogen production by the placenta under such conditions.


Developmental changes in the responses of the adrenal glands of foetal sheep to endogenous adrenocorticotrophin, as indicated by hormone responses to hypoxaemia. The change in plasma ACTH and corticosteroid concentrations in response to a 60 min period of hypoxaemia were studied in foetal and adult sheep during the latter half of pregnancy. Hypoxaemia consistently caused large rises in the concentration of ACTH in foetal plasma, the magnitude of which did not change with gestational age but was related to the physiological state of the foetus. Before 139 days small and slow rises in corticosteroid (predominantly cortisol) concentration in foetal plasma were observed during hypoxaemia, and these may have been of maternal origin. After 139 days, hypoxaemia caused a rapid and large rise in the concentration of cortisol and corticosterone in foetal plasma, which was largely of foetal origin. Hypoxaemia caused no consistent change in maternal plasma ACTH concentration but was associated with progressive increases in plasma cortisol concentrations. The cortisol: corticosterone ratio in foetal plasma was 1-5 before 139 days and increased to 4-1 several days before term which was lower than the value of 9 in maternal plasma. Small concentrations of 11-deoxycortisol and cortisone were detected in maternal and foetal plasma, the changes of which were small during hypoxaemia. The results indicate that a maturational change in the sensitivity of the foetal adrenal to endogenous ACTH occurs several days before term.


Changes in the concentration of adrenocorticotrophin and corticosteroid in the plasma of foetal sheep in the latter half of pregnancy and during labour. The changes in plasma ACTH concentration of pregnant sheep and their foetuses during the latter half of pregnancy and during labour were studied. Before 140 days of gestation the mean concentration in foetal arterial plasma was 117+/-19 (S.E.M.) pg/ml which rose to a mean of 286+/-63 pg/ml. The rise in ACTH occurred at about the same time as, but not before, the rise in corticosteroid concentration in foetal plasma. The maternal plasma ACTH concentration did not change during the latter half of pregnancy and had a mean concentration of 64+/-9 pg/ml. During labour there was a progressive rise in the ACTH concentration in foetal plasma which was not associated with any corticosteroid changes. Ethanol did not suppress labour but reduced the ACTH concentration in foetal plasma.


Control of adrenocorticotrophin secretion by catecholamines in the pregnant and foetal sheep. The effect of adrenaline on the maternal and foetal plasma ACTH concentration of twelve pregnant sheep with chronically implanted vascular catheters has been studied. Adrenaline infused into the jugular vein of the ewe or foetus produced carotid arterial adrenaline concentrations of 1-9 ng/ml. The foetal plasma ACTH was 253 +/- 73 pg/ml and it showed a fivefold increase during adrenaline infusion; the ACTH concentration achieved was proportional to the plasma adrenaline. In the ewe plasma ACTH was 99 +/- 23 pg/ml. During adrenaline infusion to the ewe this rose by an amount dependent on the adrenaline concentration achieved and there was also a rise in foetal plasma ACTH but no consistent change in foetal plasma adrenaline. There was no reproducible change in plasma corticosteroid concentration during adrenaline infusion into the foetus but a rise in maternal plasma corticosteroid concentration during infusion into the ewes. Because the adrenaline concentrations achieved during the infusions were within the physiological range, the results indicate that circulating catecholamines may directly or indirectly influence the concentration of ACTH in the circulation. Also, physiological rises in plasma catecholamines in pregnant animals may stimulate the release of ACTH from the foetal pituitary.


Differences between in-vitro and in-vivo potencies of corticotrophins: an interpretation in terms of metabolic stability. Relative activities of a series of corticotrophin analogues have been measured by means of five different bioassays using the rat. Similarities in the relative potencies of various ACTH analogues determined using lipolysis or steroidogenesis in vivo and for the lipolytic and steroidogenic responses of fat pads and adrenal slices in vitro emerged and support the concept of a close structural relationship between the ACTH receptors in adipose and adrenal tissues in the rat. Potencies based on the steroidogenic response of isolated adrenal cells, adrenal slices or in-vivo experiments differed markedly from each other. Inactivation of peptides did not occur in the isolated cell assay, so it is likely that this assay estimates potency at the receptor level. A number of arguments suggest that the difference between the isolated cell assay and the other steroidogenic assays lies solely in the effects of peptide inactivation in the latter, and this allows the relative metabolic stabilities for the peptide analogues in these assays to be calculated. In this way it can be shown that: (1) Replacement of L-Ser by D-Ser in amino acid position 1 markedly increases the metabolic stability of the peptide and has only a slight effect on receptor properties. (2) Shortening at the NH2-terminus reduces the activity of peptides at the receptor level by several orders of magnitude, but increases their relative metabolic stability. (3) Introduction of amide groups at the CO2H-terminus markedly increases receptor potency of (1-16), (1-17) and (1-18) ACTH without affecting their metabolic stability in vivo. However, amidation of the CO2H-terminus does have a large effect on metabolic stability in the adrenal slice assay. (4) Replacement of Arg by Lys in positions 17 and 18 of (1-18) ACTH increases potency at the receptor level (adrenal cells) but has little effect on metabolic stability. The comparison of potencies obtained in the various assays, therefore, throws light on the significance of each assay. In addition, the effects of structural modification of analogues can be separately evaluated with respect to the metabolic stability of a peptide and its potency at the receptor level.


Induction of melanogenesis in the epidermal melanoblasts of newborn mouse skin by MSH. The number of melanocytes positive to the dopa reaction in the epidermis was shown to increase after newborn mice were injected with alpha-MSH or DBc-AMP. The agents seemed to induce the initiation of melanogenesis in the pre-existing melanoblasts. Electron-microscopic observation also demonstrated that alpha-MSH induced not only maturation of melanosomes but also the formation of melanosomes.


Electrical potentials from the eye and optic nerve of Strombus: effects of electrical stimulation of the optic nerve. 1. Photic stimulation of the mature eye of Strombus can evoke in the optic nerve 'on' activity in numerous small afferent fibres and repetitive 'off' bursts of afferent impulses in a smaller number of larger fibres. 2. Synchronous invasion of the eye by electrically evoked impulses in small optic nerve fibres (apparently the 'on' afferents, antidromically activated) can evoke a burst of impulses in the larger 'off' fibres which propagate away from the eye. Invasion of the eye via one branch of optic nerve can evoke an answering burst in another branch. 3. Such electrically evoked bursts are similar to light-evoked 'off' bursts with respect to their impulse composition, their ability to be inhibited by illumination of the eye, and their susceptibility to MgCl2 anaesthesia. 4. Invasion of the eye by a train of repetitive electrically evoked impulses in the absence of photic stimulation can give rise to repetitive 'off' bursts as well as concomitant oscillatory potentials in the eye which are similar to those normally evoked by cessation of a photic stimulus. 5. The electrically evoked 'off' bursts appear to be caused by an excitatory rebound following the cessation of inhibitory synaptic input from photoreceptors which can be antidromically activated by electrical stimulation of the optic nerve. 6. The experimental results suggest that the rhythmic discharge of the 'off' fibres evoked by the cessation of a photic stimulus is mediated by the abrupt decrease of inhibitory synaptic input from the receptors.


Lymphocyte surface modulation and cyclic nucleotides I. Topographic correlation of cyclic adenosine 3':5'-monophosphate and immunoglobulin immunofluorescence during lymphocyte capping. The cross-linking of human peripheral lymphocyte surface Ig results in an early association of cyclic adenosine 3':5'-monophosphate (cAMP) and the cell surface Ig patches. Examination of the subsequent stages of cap formation reveals the continued relationship of cAMP and the clustered surface Ig. In addition, the generalized influx of calcium produced by the ionophore A-23187 disrupts human lymphocyte caps. During the process of cap dissolution cAMP is still associated with surface Ig. Therefore, it is hypothesized that the localized concentration of cyclic nucleotide and calcium ion regulates the movement of cell surface constituents by coordinating the function of the cell's contractile and structural elements.


Lymphoma in cotton-top marmosets after inoculation with Epstein-Barr virus: tumor incidence, histologic spectrum antibody responses, demonstration of viral DNA, and characterization of viruses. 6 of 20 cotton-top tamarins (Saguinus oedipus) inoculated with Epstein-Barr virus (EBV) developed diffuse malignant lymphoma resembling reticulum cell or immunoblastic sarcoma of man. Hyperplastic lymphoreticular lesions were induced in three additional animals; in two instances the hyperplastic lesions regressed. Inapparent infection with development of antibody occured in eight animals. In two animals there was no evidence of EBV infection. One animal died in the first week after inoculation of parasitic infection. 10 animals uninoculated or mock-inoculated developed neither lymphoproliferative disease nor antibody. The malignant lymphoma appeared to arise from a cell with an uncleaved vesicular nucleus found in the center of the germinal follicle. The prominent cytologic features of this cell were extensive formation or rough endoplasmic reticulum and elaboration of the cytoplasmic membrane with microvilli. Cell lines derived from these tumors did not have receptors for complement. IgFc, or sheep erythrocytes, and the cell lines adhered to glass and plastic. EB nuclear antigen was found in imprints of two lymph nodes, one with lymphoma and one with hyperplasia. EB virus DNA was detected directly in the tumors of three animals and in cell lines from two lymphomas. Typical herpes virus particles were found in supernatant fluids from cell lines obtained from lymph nodes with tumors and hyperplasia, as well as in lines derived from blood leukocytes of marmosets with inapparent infection. These virus preparations had the biologic property characteristic of EBV, namely, stimulation of cellular DNA synthesis and immortalization of human lymphocytes. The virus derived from two cell lines was neutralized by reference human sera with EBV antibody and not by antibody-negative human sera. The virus derived from the experimental lesions is thus indistinghishable from human EBV. The marmoset has enhanced susceptibility to oncogenesis by EB virus. Among identified factors which may play a role in the heightened tumorigenicity of EB virus in this species are the increased production of virus by transformed cells and the absence of membrane receptors for complement or IgFc on transformed cells.


Plasma levels of a viral protein as a diagnostic signal for the presence of mammary tumor: the effect of tumor removal. We have previously shown (1, 2) that mice with mammary tumors can always be identified by their very high plasma levels of gp52, a 52,000 mol wt glycoprotein of the mouse mammary tumor virus (MMTV). The present investigation demostrates that the tumor is the principal source of the plasma gp52 since surgical excision is invariably followed in the first 9 days by a sharp decreasing (10-100-fold) of the gp52 levels. Control animals in which the tumors were left in place by a "sham" surgical procedure maintained their high level of gp52, which continued to increase as the disease progressed. The behavior of the gp52 after surgical removal suggests that gp52 plasma concentrations are diagnostically and prognostically informative, as indicated by the following finding: (a) All tumor recurrences were correctly diagnosed by increases in gp52 levels, and some were detected 4-7 days before they were found by palpation. (b) Tumor regrowths were accompanied by continued increases in plasma gp52 concentrations at rates that usually matched the speed of tumor development. (c) The only animals that remained tumor free at the termination of the experiment were those that maintained their gp52 levels at or below 15 ng/ml. (d) The probability of a tumor-free animal relapsing within 2 wk is much higher if its gp52 level is above the mean. (e) More remarkably, the plasma levels of gp52 at the time of surgery are superior to the size of the tumors removed as prognostic indicators of eventual surgical "cures". The availability of a specific and sensitive systemic measure of disease status should augment the usefulness of the murine mammary tumor model by catalyzing a more rapid acquisition of information on the therapeutic effectiveness of the new and varied drug combinations being tested for adjuvant chemotherapy.


Changes in cyclic GMP levels during forelimb regeneration in adult Notophthalmus viridescens. Cyclic 3', 5'-guanosine monophosphate (cGMP) was measured at eight stages of forelimb regeneration in adult newts and compared with the cGMP levels of non-regenerating control limbs. There was a significant increase in cGMP content during dedifferentiation followed by a sharp decrease to minimal levels at the cone stage. A second smaller increase in cGMP occurred between the cone stage and mid-differentiation, followed by a decrease to relatively constant levels approaching control values as differentiation progressed. The changes in cGMP during dedifferentiation and during the period of highest cell proliferation indicate that cGMP may play a role in these processes. The smaller increases in cGMP levels during differentiation may reflect a reduced rate of cell division in the differentiating tissues.


The effect of sodium chloride and NADH on the growth of six strains of haemophilus species pathogenic to chickens. Six strains of Haemophilus species, pathogenic to chickens, required 1-0 to 1-5% (w/v) NaCl for optimum growth. The requirement was for Na+ rather than NaCl. A sodium salt buffer influenced the optimum NaCl requirement and enhanced growth. Each strain required a different concentration of NADH for an optimum rate of growth.


Expression of Klebsiella nif and his genes in Salmonella typhimurium. Derivatives of Salmonella typhimurium carrying F prime or P prime plasmids with Klebsiella nif and his genes had specific nitrogenase activities similar to Klebsiella in selective conditions, even to showing "hyperinduction" under argon. No evidence was obtained for catabolite repression of normal nif expression but dibutyl cyclic AMP often augmented "hyperinduction". In non-selective conditions the Klebsiella his nif determinants were rapidly lost from the plasmids; the low levels of nif expression and temperature-sensitive his expression previously reported were probably due to ready loss of his nif in the test conditions used.


Induction of Marek's disease virus antigens by IdUrd in a chicken lymphoblastoid cell line. Marek's disease virus (MDV) antigens, as detected by immunofluorescence, were induced in a lymphoblastoid cell line, MSB-I, in the presence of IdUrd. When treated with 20 microng/ml of IdUrd there was no increase in the number of cells producing virus particles. If IdUrd was removed, an increase in virus production followed. Activation of the MDV genome appeared to require incorporation of IdUrd into cellular DNA and occurred during the first 12 h of culture. Expression of the activated genome required de novo protein synthesis and occurred during the next 12 h. The MDV genome in high producer MSB-I cells could be activated with low concentrations of IdUrd, whereas low producer MSB-I cells could not be activated with IdUrd to any great extent.


Comparison of the polypeptides of several strains of human cytomegalovirus. Analysis of purified human cytomegalovirus (CMV) by sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed 32 polypeptides with mol. wt. ranging from 13,500 to 235,000. Similar analysis of purified preparations of four strains of CMV showed a remarkable similarity in polypeptide composition. Results indicate that the four strains may be related.


Differences in the physical properties of dense and standard poliovirus particles. Dense poliovirus particles (DP) differ in buoyant density, sedimentation coefficient and lability from standard poliovirus particles. Dense particles band at a density of 1-44 g/ml in isopycnic CsCl gradients and sediment in sucrose gradients at 220S. However, when DP are centrifuged in sucrose gradients containing 1-5 M-KCl, NaCl or LiCl, two types of particles are observed, one sedimenting at 220S and the other at 160S. Particles sedimenting at 220S are converted into particles sedimenting at 160S by incubation at 37 degrees C in 1-5 M-KCl. The high buoyant density seems to be correlated with the high lability of DP. Dense particles are extremely labile in isotonic phosphate-buffered saline. Their degradation proceeds through an RNA-containing particle lacking polypeptide VP4, to RNA and empty capsids.


Electron microscopy of herpes simplex virus DNA molecules isolated from infected cells by centrifugation in CsCl density gradients. Herpes simplex virus (HSV) DNA molecules were isolated from infected BSC 1 cells and centrifuged in CsCl-ethidium bromide density gradients. Both newly labelled and mature virus DNA molecules were found to have a linear conformation. The morphology of virus DNA molecules at different stages of the virus growth cycle in BSC 1 cells, was studied by electron microscopy after separation of virus DNA from cellular DNA by centrifugation in CsCl gradients. In each sample, about 200 virus DNA molecules were photographed and the different morphological forms were studied. Four classes of virus DNA molecules were observed: (a) mature linear DNA molecules, 52-4 +/- 3-3 micronm in length, (b) DNA intermediates, (c) virus DNA molecules having one or more single-stranded filaments attached to them and (d) molecules with collapsed regions or with branches. A few circular molecules as well as linear DNA molecules longer than unit length were also observed. The virus DNA molecules resembling replicative intermediates gradually increased in number and reached a maximal amount of about 5% of the virus DNA population at 12 h after infection. The other forms of virus DNA were found to persist after the number of replicating DNA molecules decreased.


Lipids of transmissible gastroenteritis virus and their relation to those of two different host cells. The lipids of two cell types (primary pig kidney and secondary adult pig thyroid) and those of transmissible gastroenteritis virus (TGEV) grown in these cells were studied using 14C-palmitic acid. Differences were demonstrated between the incorporation of isotopically labelled lipid precursors in the two cell types and it was found that the phospholipid and glycolipid profiles of purified TGEV closely resembled those of the host cell in which it was grown.


Effects of ouabain on the anticellular and antiviral activities of human and mouse interferon. When transformed human embryonic cells, RSa and RSb, were treated for 48 h with both 10(-7) M-ouabain and 1000 units/ml of human leucocyte inteferon, there was an additive suppression of cell growth. In contrast, the antiviral action of the human interferon was inhibited by this concentration of ouabain. Similar effects of combined treatment with interferon and ouabain were found with IFr cells (which are relatively resistant to the anticellular effect of interferon), and with mouse cells of the K3b line.


Genetic control of resistance to subgroup A and subgroup C tumour viruses in Rhode Island Red fowl: evidence for linkage between the tumour virus a (tva) and tumour virus c (tvc) loci. A study, using the Rhode Island Red (RIR) strain of fowl maintained at Houghton Poultry Research Station, was made to investigate the genetic control of cellular response to infection with viruses of subgroups A and C. Family matings within the RIR strain and test-crosses between the RIR parents and White Leghorn (WL) parents of known ararcrcr genotype were set up to ascertain linkage between the tumour virus a (tva) and tumour virus c (tvc) loci. The results confirmed that in this RIR strain, the two loci, tva and tvc, control the cellular response to viruses of subgroups A and C, respectively, as reported in other breeds of fowl (WL and New Hampshire). As in WL fowl, the two loci are linked. The linkage value of 0-22 in the male sex agreed well with that reported in the WL male sex, indicating that the two loci are located in the same sites in homologous chromosomes in the two breeds. However, in the RIR strain, no sex difference in crossing over between the two linked loci was found, contrary to that reported in WL fowl where the absence of crossing over between the two loci was observed in the heterogametic female sex.


Immunogenic and cell attachment sites of FMDV: further evidence for their location in a single capsid polypeptide. Chymotrypsin cleaves only one of the four major polypeptides of foot-and-mouth disease virus (FMDV serotype O) in situ. This polypeptide (VP1, mol. wt. 29 X 10(3) was first cleaved into fragments of mol. wt. 20 and 9 X 10(3) and further cleavage could be prevented by the addition of a large excess of bovine serum albumin. The infectivity of the virus particles at this stage was the same as that of the intact virus although the rate of attachment to BHK 21 cells was slower and the immunogenic activity was reduced. If hydrolysis was allowed to continue, VP1 was cleaved into fragments with mol. wt. 18 and less than 9 X 10(3), similar to those obtained with trypsin and the virus particles then had a greatly  reduced infectivity and a lower immunogenicity. Treatment of strains from five other serotypes of the virus with the two enzymes cleaved only VP1 in each instance and there was a corresponding loss of infectivity. The results are discussed in relation to the location and biological activity of the virus polypeptides.


Thymidine transport in herpesvirus hominis type 1 and 2 infected BHK 21 cells. Increase of dThd-uptake 4 to 12 h after infection of BHK or primary rabbit kidney cells with Herpesvirus hominis of type 1 or 2 can be considered as an early function of the virus genome, because the presence of Cyd-Ara does not prevent the increase of uptake. However, increase of uptake can be prevented by addition of actinomycin D and cycloheximide early in the synthetic cycle. Two modes of uptake have been differentiated by kinetic analysis: at low substrate concentration dThd is taken up by 'facilitated transport', whereas at high substrate concentration (above 2-5 micronM) simple diffusion takes place. The Km of transport of normal BHK or primary rabbit kidney cells (1-4 or 0-5 micronM respectively) is not changed after infection. Only the Vmax increases from 8 to 26-6 pmol in BHK cells or from 2-9 to 9-0 pmol in primary rabbit kidney cells. This indicates that 'carrier sites' with identical affinity for dThd-transport are responsible for the increase of transport after infection. This increase of transport is correlated with the induction of a virus coded thymidine kinase (TK) and not with different types of c.p.e. or cellular damage. Transport of BdUrd increases in a similar manner to that of dThd after infection; transport of dCyd or dUrd increases only slightly, whereas the mechanism of dAdo or Urd uptake by infected cells is quite different.


Radioactive labelling of viruses: an iodination technique preserving biological properties. An iodination procedure suitable for the radioactive labelling of viruses to be used in biological experiments is described. It is characterized by the addition of carrier protein to small amounts of virus before iodination with chloramine T, the use of low concentrations of chemicals, and a rapid purification of the labelled virus to minimize radiation inactivation. Using this procedure, polyoma virus was labelled to a specific activity 100 times greater than that which can be obtained with tritiated amino acids, while its sedimentation coefficient, buoyant density, decapsidation and hamagglutinating activity remained unaffected. Reduction in infectivity, possibly due to radiation inactivation, was slight. Similar results were obtained with adenovirus.


Role of sialic acid in infection with vesicular stomatitis virus. The role of sialic acid in the infection of tissue culture cells and mice with vesicular stomatitis virus has been studied. No loss of infectivity of the Indiana serotype of the virus was detected by incubating with neuraminidase although the virus particles had lost sialic acid as judged by their ability to inhibit the agglutination of red blood cells by influenza virus. The results did not depend on the type of cell used for growth and assay of the virus since essentially similar findings were made in BHK cells, L cells or mice. Similar results were obtained with Brazil virus, a subtype of the Indiana serotype and with the New Jersey serotype. We consider that the sialic acid of the virus which is removed by neuraminidase does not play a major role in the infectivity of the virus.


Heterotypic exclusion between vesicular stomatitis viruses of the New Jersey and Indiana serotypes. Co-infection of cells with vesicular stomatitis viruses of the Indiana and New Jersey serotypes results in interference. Using specifically-labelled immunofluorescent antibodies, it was demonstrated that within any one co-infected cell, one virus serotype replicated to the relative exclusion of the other serotype. This result was further substantiated by an examination of the virus serotypes released by infectious centres co-infected with both viruses. Dominance of one serotype over the other was shown to be a function of the relative multiplicity of the two viruses. Superinfection by the second serotype at a higher multiplicity resulted in dominance by the second virus during the early period (up to 1-5 h) post-infection. After this time, the minority virus was able to overcome this dominance. Dominance of the majority virus was also abolished by u.v; inactivation. Cell protein synthesis appeared to be less affected in cells infected with both serotypes than when infection was with a single serotype.


Requirement of the bacteriopahge T7 0.7 gene for phage growth in the presence of the Col 1b factor. A variety of colicinogenic factors were examined for their effect on the growth of phages related to T7. Col B1 and Col B4 inhibited the growth of every phage tested. Col B2, however, did not interfere with T3 and H. Col E2 interfered only with growth of T3, while Col Ib produced abortive infection with some T7 mutants. The abortive infection associated with Col Ib seems to be correlated with the absence of the virus phosphokinase; mixed infection with T7 wild type and a phosphokinase deficient mutant was productive but the phage yield was depressed. The abortively infected cells lysed.


The adrenal medulla may mediate the increase in pineal melatonin synthesis induced by stress, but not that caused by exposure to darkness. As previously shown (Lynch et al.: Proc. Nat. Acad. Sci. [U.S.A.] 70, 1704-1707 [1973]), the activity of the enzyme serotonin-N-acetyltransferase (NAT) in the rat pineal increases when the animal is placed in darkness or is subjected to the stress of physical immobilization; partial sympathetic denervation (i.e., pretreatment of the animal with intravenous 6-hydroxydopamine [6-OHDA]) does not block either response. The present studies explored the roles of the pineal sympathetic nerves and the adrenal medullas in mediating these responses. The stress-induced increase in pineal NAT activity was blocked by bilateral adrenalectomy, but not by bilateral superior cervical ganglionectomy or by treatment with 6-OHDA (both of which potentiate the NAT response in normal rats and restore it in adrenalectomized ones). The increase in pineal melatonin content caused by immobilization was also blocked by adrenalectomy, but potentiated by pineal sympathetic denervation. In contrast, bilateral adrenalectomy did not affect the darkness-induced rise in pineal NAT activity, although pineal sympathetic denervation (by bilateral superior cervical ganglionectomy) did block this response. 6-OHDA pretreatment neither blocked the response to darkness nor restored it in ganglionectomized animals; thus, this treatment apparently fails to produce a complete pineal denervation. The pineal response to stress has previously been shown to be blocked by beta-adrenergic blocking agents. The present studies demonstrate that alpha-adrenergic blockade (with phenoxybenzamine) potentiates this response in intact animals and restores it in adrenalectomized rats (possibly by acting presynaptically on receptors on pineal sympathetic terminals and thereby augmenting norepinephrine release). These observations show that the rat pineal organ normally receives information from two "channels", i.e., trans-synaptically (from pineal sympathetic nerves) and via the circulation (from the adrenal medullas and, perhaps, from distant sympathetic nerves).


Comparative effects of herpes simplex virus types 1 and 2 in organotypic cultures of mouse dorsal root ganglion. Mature organized cultures of mouse dorsal root ganglion (MDRG) were infected with herpes simplex virus, type 1 (HSV 1) and type 2 (HSV 2). Onset of infectious virus production occurred faster and reached higher levels in HSV 2-infected cultures. Neurons, supporting cells and myelin were affected in both types of infection, but morphological changes occurred significantly earlier and more dramatically with the type 2 infection. The pattern of myelin changes was distinctly different in the two types of infection. Within 20 hours post infection nerve cells infected with HSV 2 developed several types of intranuclear inclusions consisting of membranes and filaments; no such neuronal inclusions were seen with HSV 1 infection. HSV 2 infection showed frequent, large, membranous inclusions in supporting cell nuclei whereas, only rare, small inclusions of this type were seen in supporting cells infected with HSV 1. The observations demonstrate that the two virus types produced different virus replication patterns and different morphologic changes in long term cultures of MDRG. There appears to be a differential response of neurons and non-neuronal elements to the virus in this tissue substrate. Viral latency was not induced in this system by direct inoculation of the virus under the conditions described.


Computerized tomography as a possible aid to histological grading of supratentorial gliomas. Computerized tomography (CT) is known to be very helpful in demostrating the presence and extent of supratentorial gliomas, practically in combination with intravenous injection of contrast material. Certain specific density patterns were found to exist and enabled us to differentiate with confidence the low-grade gliomas from the glioblastomas. Overlapping did occur, however, as was to be expected, since histological proof was sometimes obtained by the needle biopsy with its inherent doubt as to true tumor representation. Future CT techniques such as sequential scanning after intravenous injection of contrast material may further increase the usefulness of CT scans in the diagnosis and therapeutic approach to the patient with a suspected glioma.


Intracranial biopsy assisted by computerized tomography. A technique is described for biopsying intracranial tumors and aspirating cysts or abscesses using flexible non-metallic needle guides and computerized tomography a guidance system. Three cases are described in which this technique was used.


The scintigraphic investigation of sacroiliac disease. Bone scintigraphs obtained with both Technetium-99m polyphosphate and Technetium-99m pyrophosphate have been abnormal at the sacroiliac joints of 44 patients with definite ankylosing spondylitis (AS). Because of the normal registration of the sacroiliac joints on bone scintigraphy, it has been necessary to develop a profile-scan technique to quantify the abnormality that proves to be significantly different from the normal finding. In 17 patients with a strong clinical suspicion of AS but normal radiographs, the sacroiliac joints have frequently been abnormal. This finding is meaningful because there is a common occurence in this group of the histocompatibility antigen HL A-B27, known to be a marker of AS. We also note the frequency of abnormal sacroiliac scinitigrams in 26 patients with rheumatoid arthritis and in a group of other diseases-Crohn's disease, uveitis, psoriasis, ulcerative colitis, and Reiter's disease-all of which share some of the manifestations of AS.


Evaluation of formamidine sulfinic acid and other reducing agents for use in the preparation of Tc-99m labeled radiopharmaceuticals. Various reducing agents have been evaluated for their potential usefulness in the preparation of 99mTc labeled radiopharmaceuticals for use in nuclear medicine. Adequate labeling of various radiopharmaceuticals was accomplished using formamidine sulfinic acid. Nitrogen-purging of solutions is not required, which is an advantage for in-house preparation. Tagging requires heating, however, so heat-labile material cannot be used. Various compounds that could not be labeled when stannous chloride was used, could be tagged with 99mTc when formanidine sulfinic acid was used as the reducing agent.


Effect of adaptation to meal-feeding on insulin, glucagon and the cyclic nucleotide-protein kinase system in rats. Diurnal changes in insulin, glucagon and the cyclic nucleotide-protein kinase system were examined in rats trained to eat a 2-hour daily meal and in control rats fed ad libitum. Sharp increases in both insulin and glucagon were observed in response to feeding in trained rats. However, throughout most of the rest of the day, the plasma concentrations of both hormones were lower in meal-fed than in control rats. In adipose tissue, diurnal changes in cyclic AMP concentration were inversely correlated with changes in plasma insulin concentration. In general, cyclic AMP concentrations were depressed and cyclic GMP elevated in adipose tissue of meal-fed rats compared with those fed ad libitum. Diurnal changes in cyclic GMP concentration tended to parallel those of cyclic AMP. Cyclic AMP-activated protein kinase was elevated in adipose tissue of meal-fed rats. However, with the exception of fasting rats, the percentage of the enzyme in the active form was decreased. In liver, there was no clear relation significant differenced were observed with the protein kinase. It can be concluded that the magnitude of the adaptive response of the cyclic nucleotide-protein kinase system to meal-feeding in rats is greater in adipose tissue than in liver.


Effect of zinc deficiency on the ultrastructure of the pancreatic acinar cell and intestinal epithelium in the rat. Ultrastructural changes in the pancreatic acinar cell and intestinal epithelium were studied in rats fed a zinc-deficient diet as compared with those of pair-fed and ad libitum fed zinc-supplemented controls. The pancreatic acinar cells of zinc-deficient rats showed marked cellular alterations: a reduction in zymogen granules, rupture of zymogen granules, basal accumulation lipid droplets, prominent lysosome-like bodies, focal degradation of the cytoplasm, and intracistenal granules within the dilated cisternae of the endoplasmic reticulum. The Golgi complex appeared inactive, and nuclear pyknosis was noted. Defects in the endoplasmic reticulum and ribosomes were  shown by their presence in the foci of cytoplasmic degradation, which were subsequently subject to lysosomal digestion and degeneration. The microvilli of the intestinal epithelium in the zinc deficient rats were well organized and normal in size, demonstrating a typical geometric array when cross-sectioned. The intercellular boundaries, the junctional complexes, and the terminal web were well developed and appeared intact. However, the cell cytoplasm showed prominent cellular changes: an abundance of lysosome-like bodies, membrane-bound autopraphic vacuoles, sparse endoplasmic reticulum, a quiescent-appearing Golgi complex with tightly packed lamellae containing few vacuoles, pyknotic nuclei, and a dilated nuclear periphery.


Effect of zinc deficiency on intestinal transport triglyceride in the rat. Ultrastructural and biochemical changes in the intestinal epithelium during the process of active triglyceride absorption were studied in rats fed a zinc-deficient diet as compared with those of pair-fed and ad libitum-fed zinc-supplemented controls. The rate of triglyceride absorption markedly decreased in zinc-deficient rats. Despite a significant reduction in pancreatic lipase activity, the digestion of triglycerides proceeded normally in the zinc deficient rats, as evidenced by  no apparent signs of diarrhea (or steatorrhea) and by the appearance of the hydrolytic products such as free-fatty acids and monoglycerides in the intestinal mucosa. The mucosa uptake of digested lipids and resynthesis of triglycerides in the mucosa from deficient rats were normal. Ultrastructural and chromatographic analysis of the mucosal lipids indicated a massive accumulation of lipid droplets, predominantly in the form of triglycerides. The primary defect in lipid absorptive processes in zinc-deficient rats occurred in the formation of chylomicrons. The lipid droplets in the mucosa of  deficient rats were physically unstable. This instability was shown by coalescence of droplets which did not appear to be membrane-bound. Coalescing lipid droplets ranged from 2.0 to 4.0 micron in diameter. The absorptive cells were not able to discharge lipid droplets of this size into the intercellular spaces and hence into the lamina propria, resulting in the accumulation of the large droplets within the mucosa. This exit block to the movement of lipid droplets out of the mucosal cell appeared to be due to the failure, in zinc-deficiency, of the mucosal synthesis of proteins required for the formation of chylomicrons. Ultrastructural observations demonstrated changes in the subcellular organelles related to protein synthesis, including a marked reduction in granular endoplasmic reticulum and a quiescent appearance of the Golgi-complex.


Role of dietary calcium and calcium binding protein in cadmium toxicity in rats. Growing male rats were fed a purified diet containing 0.6% Ca (two groups) or 0.1% Ca (two groups) for 8 weeks. One 0.6% Ca group and one 0.1% Ca group received 25 ppm Cd (as CdC12) in the drinking water. Diets were fed on an equalized basis with the 0.1% Ca + Cd group determining the amount of diet fed to the other groups. Water was provided ad libitum. Terminal body weights were not different among the four groups. Packed cell volumes were depressed in the Cd-exposed groups, especially the 0.1% Ca + Cd group. The highest concentrations of Cd were found in the lungs, liver, and kidneys of the 0.1% Ca + Cd group. More Cd was bound to low molecular weight proteins of the intestinal mucosa from the 0.1% Ca + Cd group than the 0.6% Ca + Cd group. Rats fed the 0.1% Ca diet appeared to have a greater capacity to absorb either Ca or Cd than rats fed the 0.6% Ca diet, as shown by an enhanced binding of 45Ca and  115mCd to intestinal calcium-binding protein (CaBP) in the rats fed the low calcium diet. A portion of the mucosal Cd was accounted for as Cd bound to metallothionein. It was concluded, based upon these experiments, that cadmium retention and signs of toxicity are enhanced by feeding low Ca diet and that the increased CaBP activity due to Ca restrictions is responsible for the increased Cd uptake observed.


Problem of sex ratio in cases of type I syndactyly. Fifty pedigrees of type I syndactyly were analysed for sex ratio and segreation pattern. Thirty-four of the pedigrees were from the published reports; 16 were collected in the State of Utah. Pedigrees with affected individuals showing webbing between the second and third toes are characterized by a sex ratio of affected individuals favouring males and a highly significant excess of affected sons of heterozygous fathers. A similar distorted segregation pattern is present in those pedigrees when the webbing involves the second and third toes and/or the third and fourth fingers, but not in those pedigrees when the webbing involves other digits. The reason for the distorted segregation pattern is unknown. Hypothesis include abnormal chromosome segregation and gametic selection.


A partial long arm deletion of chromosome 7:46,XY,del(7)(q32). We have identified a partial deletion of the long arm of chromosome 7 in a newborn baby boy. His major anomalies were microcephaly, synbrachydactyly, diastisis recti, hypospadias, short neck, and widely spaced nipples.


Reovirus-like agent as a cause of nosocomial diarrhea in infants. Surveillance for nosocomial diarrhea due to a reovirus-like agent was maintained on the pediatric wards of a large metropolitan hospital in January and February, 1976, during a large community outbreak of that illness. During this period, 30 (27%) of 111 children under surveillance were admitted for dehydration secondary to diarrhea; 21 (70%) of these 30 children had RLA in stool samples obtained at admission. Ten (17%) of the 60 children admitted without diarrhea, hence at risk of acquiring nosocomial RLA infection, contracted the illness. With human RLA as an antigen, no hospital personnel had serologic (complement fixation test) evidence of infection. Early attempts to control the diarrhea at home and in the outpatient department by the use of oral fluid rehydration, isolation of patients with severe symptoms requiring hospitalization, and strict attention by hospital personnel to hand washing between examination of patients may limit nosocomial spread of the disease.


Endocrine function following the treatment of acute leukemia in childhood. Pituitary function has been studied in 25 children after treatment of acute leukemia. Impaired growth hormone responses both to hypoglycemia and to Bovril were found in 11 subjects. Elevated basal thyroid-stimulating hormone levels were seen in five children, three of whom had an augmented TSH response to thyrotrophin-releasing hormone. Radiation-induced damage to the hypothalamic-pituitary region is thought to be the cause of these abnormalities in growth hormone and in secretion of TSH. The peak cortisol response to hypoglycaemia is significantly decreased in the group of subjects who received the higher dose of cranial radiation therapy, but no individual child is hypothyroid or shows impaired adrenal function, clinically or biochemically. Three prepubertal girls studied have biochemical evidence of ovarian failure following the use of combination chemotherapy.


The detection of the heterozygous carrier for congenital virilizing adrenal hyperplasia. The response of plasma progesterone, 17 alpha-hydroxyprogesterone (17-OHP), and cortisol to intravenous ACTH was determined in 16 control subjects and seven sets of parents of children with congenital virilizing adrenal hyperplasia. The baseline and poststimulation concentrations of hormones (of each group) were similar except for those of 17-OHP in the parents which were significantly greater following administration of ACTH. When rates of increase were determined, those of progesterone and 17-OHP but not cortisol were significantly greater in the parents. The combined rate of increase of progesterone and 17-OHP was calculated; 10 of the 14 parents had a combined rate of increase greater than the mean plus two standard deviations of the control group. This test provides a simple method for the detection of some heterozygous carriers for CVAH.


"Flecked retina" --an association with primary hyperoxaluria. A child with hyperoxaluria, probable Type I, was noted to have a "flecked retina" on funduscopic examination at age 2 1/2 months; it persisted throughout his seven years of life. The relationship of the ocular findings to his metabolic disease is discussed.


GLC assay of conjugated estrogen formulations. A procedure is described for the enzyme hydrolysis and GLC assay of conjugated estrogens in commercial formulations. Resolution of up to nine of the components is achieved on a methyl phenyl cyanopropyl silicone-coated column using a dual-derivatization and dual-injection technique. Replicate results from analyses of a commercial tablet formulation yielded coefficients of variation between 1.0 and 17.2%, depending mainly on the quantity present; a coefficient of variation of 0.4% was obtained for the assay for total conjugated estrogens. Similar results were obtained with other commercial formulations.


Cutaneous facilitation of transmission in reflex pathways from Ib afferents to motoneurones. 1. The effect of volleys in low threshold cutaneous afferents upon transmission of synaptic action from Ib afferents to motoneurones has been investigated with intracellular recording from alpha motoneurones to hind limb muscles. 2. There was facilitation from cutaneous afferents of transmission in excitatory and inhibitory reflex pathways from Ib afferents without any evidence for difference in effect on di- and trisynaptic pathways. It is postulated that volleys in cutaneous afferents evoke excitatory action in interneurones of these reflex pathways. 3. The time course of the facilitation suggest that cutaneous afferents have disynaptic excitatory connexions with the interneurones intercalated in the disynaptic Ib inhibitory pathways to motoneurones. 4. Some observations are reported suggesting that interneuronal transmission in Ib inhibitory pathways to motoneurones might be facilitated from Ia afferents. 5. The findings are discussed in relation to the presumed role of Ib reflex action in regulating muscle tension.


Effect of implantation of an extra nerve on the recovery of neuromuscular transmission from botulinum toxin. 1. The common peroneal nerve was implanted into soleus in the mouse and 2 weeks later a sublethal dose of botulinum toxin injected causing a block of neuromuscular transmission at the terminals of the soleus nerve. Most muscle fibres became innervated by the common peroneal nerve. 2. Recovery of neuromuscular transmission at the soleus nerve terminals was delayed in the common peroneal nerve implanted muscles. 3. Stimulation of the soleus nerve after botulinum-evoked subthreshold end-plate potentials (e.p.p.s) in virtually every fibre tested in unoperated muscles. In common peroneal nerve-implanted muscles stimulation of the soleus nerve failed to evoke e.p.p.s in about 40% of fibres tested and where e.p.p.s were recorded their amplitudes were generally smaller. 4. When the common peroneal nerve was cut 2 months after botulinum, neuromuscular transmission at soleus nerve terminals occurred after 4 weeks. When the common peroneal nerve was cut 6 months after botulinum, transmission was found at soleus nerve terminals within 1 week. 5. Recovery of transmission at soleus nerve terminals from the effects of botulinum toxin is delayed if the muscle fibres become innervated by the common peroneal nerve and a proportion of soleus nerve terminals cease to release acetylcholine (ACh) until after the peroneal nerve has been cut.


Effects of guanidine on transmitter release and neuronal excitability. 1. Guanidine hydrochloride (CH5N3-HCl) was applied to frog neuromuscular junctions blocked by reduced external Ca2+, or increased external Mg2+ concentration, or by both. Guanidine produced a dose-dependent increase in the average number of quanta released by presynaptic action potentials, the threshold dose being 0-1-0-2 mM. No post-synaptic effects were observed. 2. Guanidine also increased the excitability of the motor nerve fibres, as evidenced by multiple firing to single electrical stimuli and finally by spontaneous action potentials. These effects were studied in greater detail in giant axons (Müller axons) in the spinal cord of lamprey. Exposure to guanidine produced in these axons a progressive increase in excitability, manifested by repetitive firing to a single electrical stimulus, spontaneous membrane potential oscillations and spontaneous bursts of action potentials. Guanidine had no effect on the resting potential. 3. The effect of guanidine on the excitability of Müller axons was mimicked in every detail simply by reducing the divalent cation concentration of the bathing solution. 4. Guanidine also produced dose-dependent increases in the duration of action potentials in Müller axons. This effect always preceded in time the appearance of the excitability effects and was not mimicked by reducing the divalent cation concentration. It is suggested that the broadening of the action potential is separate from the excitability effects and may reflect a decrease of delayed rectification. 5. Guanidine (0-3 mM) increased the frequency of miniature end-plate potentials (min. e.p.p.) in solutions containing 2-11 mM-K+ in such a way as to shift the relationship between min. e.p.p. frequency and extracellular K+ toward lower values of K+. This effect was interpreted to mean that guanidine produced a depolarization of the nerve terminal which summed with the depolarization produced by a given concentration of K+. The calculated depolarization produced by 0-3 mM guanidine was 5-7 mV. 6. The effects of guanidine on evoked transmitter release, excitability, and min. e.p.p. frequency are consistent with a hypothesis which states that guanidine binds at or near fixed negative changes on the outside of nerve membrane and reduces the screening effect of divalent cations.


On the effect of calcium on the frequency of miniature end-plate potentials at the frog neuromuscular junction. 1. The effect of the extracellular Ca concentration on the frequency of miniature end-plate potentials (min. e.p.p.s) at the frog neuromuscular junction was studied. 2. In saline containing elevated K (5 or 11 mM), the frequency of min. e.p.p.s increased as Ca concentration was increased from 0-1 to 1-3 mM. However, with further increases of Ca concentration up to 10 mM, min. E.P.P. frequency declined. 3. In saline containing the normal concentration of K (2 mM), increasing Ca concentration from 0-1 to 10 mM produced a slight, monotonic increase in min. e.p.p. frequency. 4. The non-monotonic effect of Ca on min. e.p.p. frequency in preparations depolarized by elevated K is consistent with the existence of two opposing effects of Ca on transmitter release. Firstly, raising the external concentration of Ca increases the electrochemical potential for Ca entry, which tends to increase Ca influx and transmitter release. Secondly, increasing external Ca concentration increases electrostatic screening of fixed negative charges on the outer surface of the nerve terminal membrane. Such an increase in screening of charges near voltage-sensitive Ca gates would produce a hyperpolarization across the gates and they would tend to close, an effect which would tend to decrease Ca influx. The monotonic increase in min. e.p.p. frequency with increasing Ca concentration in 2 mM-K is consistent with the voltage insensitivity of the Ca gates at potentials close to the normal resting potential.


Metiamide and stimulated acid secretion from the isolated non-distended and distended mouse stomach. 1. The action of metiamide, a specific histamine H2-receptor antagonist, on the acid secretory response to various gastric stimuli in the perfused isolated whole mouse stomach is described. 2. Two kinds of stomach preparations, the non-distended stomach and distended stomach, were used. The distended stomach gave a marked and dose-related acid secretory response to histamine (10(-6) to 10(-3) M), pentagastrin (10(-8) to 10(-5) M), acetylcholine (5 X 10(-5) to 10(-5) M), eserine (10(-5) to 10(-3) M) to dibutyryl cyclic AMP (5 X 10(-5) to 10(-3) M). In the nondistended stomach, dibutyryl cyclic AMP regularly stimulated acid secretion in a dose-dependent manner; in contrast to dibutyryl cyclic AMP, histamine, pentagastrin or acetylcholine did not always stimulate acid secretion. 3. Histamine or pentagastrin but not acetylcholine always caused significant stimulation of acid secretion from the non-distended stomach in the presence of a phosphodiesterase inhibitor such as caffeine, theophylline or the I.C.I. compound, 63197. At the concentration of 10(-4) M, these phosphodiesterase inhibitors markedly potentiated the stimulatory effect of histamine or pentagastrin on acid secretion and the order of effectiveness was 63197 greater than theophylline greater than caffeine. 63197 also produced profound potentiation of histamine- or pentagastrin-stimulated acid secretion in the distended stomach. 4. Metiamide (5 X 10(-5) to 10(-4) M) did not antagonize stimulation of acid secretion by dibutyryl cyclic AMP in the non-distended or distended stomach. 5. In the distended stomach, metiamide (5 X 10(-4) M) produced significant inhibition of histamine-stimulated acid secretion with a linear and parallel displacement of the histamine dose--response curve to the right. Although at this concentration metiamide did not depress maximal acid secretory response to histamine, it caused marked reduction of the maximal acid secretory response attainable with pentagastrin. 6. In the distended stomach, metiamide (5 X 10(-5) M) did not cause significant inhibition of acetylcholine-induced acid secretion. Atropine (5 X 10(-6) M) abolished the stimulatory effect of acetylcholine; it also produced marked inhibition of pentagastrin-stimulated acid secretion but it had little effect on acid secretion induced by histamine. 7. The present results indicate that metiamide inhibited histamine-induced acid secretion by competitive antagonism of the histamine H2-receptor, but its inhibitory effect on pentagastrin-induced acid secretion seemed to be of non-competitive nature. The failure of metiamide to inhibit acid secretion induced by dibutyryl cyclic AMP suggests that cyclic AMP might regulate gastric acid secretion at a site beyond the histamine H2-receptor activation. It is also considered that the present results support the hypothesis that cyclic AMP may be involved in histamine- or pentagastrin-induced acid secretion in the isolated mouse stomach. 8...


An analysis of the action of a false transmitter at the neuromuscular junction. 1. The action of monoethylcholine (MECh) on neuromuscular transmission has been studied by electrophysiological methods. 2. End-plate potentials (e.p.p.s.) in curarized rat muscle were unaffected or slightly increased in amplitude by MECh (0-1-1 mM). Stimulation at 3 Hz for about 30 min in the presence of MECh caused a progressive decline in e.p.p. amplitude, and a shortening of the e.p.p. time course. These changes were reversed by addition of choline to the medium. Similar changes in amplitude, but no change in time course, occurred when the preparation was stimulated in the presence of hemicholinium or triethylcholine. 3. Extracellular recordings of miniature end-plate potentials in frog muscle showed that stimulation in the presence of MECh caused the time constant of the exponential decay of the m.e.p.p.s. to decrease by 42%. The amplitude of intracellular m.e.p.p.s. was reduced by 45%. These changes were maximal by the time about 3 X 10(5) quanta had been released. 4. Voltage clamp experiments in rat muscle in which miniature end-plate currents (m.e.p.c.s) were recorded showed that stimulation in the presence of MECh reduced the amplitude (by 33%) and the decay time constant (by 42%). 5. Analysis of end-plate current flucutations produced by local application of acetylcholine (ACh) and acetylmonoethycholine (AMECh) to voltage clamped rat end-plates showed that the amplitude of the elementary current events was the same for both compounds whereas the average channel lifetime was 44% shorter for AMECh than for ACh. 6. The voltage-sensitivity of the channel lifetime (measured from end-plate current fluctuations) was the same for ACh and AMECh. The voltage-sensitivity of the m.e.p.c. decay time constant was the same as that found from noise measurements. The shortened m.e.p.c.s. (false m.e.p.c.s.) occurring after stimulation in the presence of MECh also showed the same voltage-sensitivity. 7. Both normal and false m.e.p.c.s. were prolonged by neostigmine by almost the same factor; false m.e.p.c.s. were thus shorter than normal m.e.p.c.s. even when cholinesterase was inactivated. Experiments with progressive curarization of neostigmine-treated end-plates suggested that the fraction of transmitter molecules bound is smaller for false than for normal m.e.p.c.s. The difference implies that the false transmitter has one quarter of the affinity of ACh for the receptors. 8. It is concluded that stimulation in the presence of MECh gives rise to a false transmitter, presumably AMECh, which has a lower affinity for receptors than ACh, and gives rise to ionic channels with a shorter average lifetime than those activated by ACh.


Multiple unit activity recording in the corticotropic area of the deafferented hypothalamus and corticosteronemia in the pigeon. 10 Diurnal variations in both multiple unit activity and plasma corticosterone level were suppressed after complete neural isolation of the basal hypothalamus in the pigeon. 20 It is suggested that the circadian activity of the hypothalamic pituitary corticotropic unit partially depends upon the inhibiting influence from the hippocampic-septal structures.


[Inhibitory mechanisms within the receptive fields of X-and Y-type retinal ganglion cells of the cat (author's transl)]. Two-stages of the inhibitory mechanisms were assumed within the on-center receptive field (RF) of the cat's retinal ganglion cell on the basis of the following two experiments: 1) Effect of background intensity upon the magnitude of the response to the RF-centered spot of stimulus, and 2) the time course of the inhibitory effect when the additional spot of light is presented in the same RF center region. The first stage is an inhibitory feed-back from horizontal cell to the photoreceptor. Both X-and Y-fields have this feed-back route. By this gain control machanisms, the ganglion cell will respond to the intensity ratio of the spot to the background. [corrected] The second stage of inhibitory mechanism in X-field is the feed-back from sustained amacrine cell to the bipolar cell. Above two stages of feed-back mechanism in X-field explain the strong maintained suppressive effect produced by the additional spot of light. On the other hand, the Y-type ganglion cell will recive the inhibitory input via feed-forward path from trannsient amacrine cell. This explains the transient on- and of f-suppressive effects


The activity of polymyxins against Escherichia coli in an in-vitro model of the urinary bladder. The activities against a strain of Escherichia coli of polymyxin B, colistin (polymyxin E) and their sulphomethyl derivatives sulphomyxin and colistin sulphomethate have been examined in an in-vitro model of the urinary bladder under conditions similar to those that may operate in the therapeutic situation. In the dynamic conditions of the model, polymyxins exhibited a reduced activity against E. coli in comparison with activity against exponentially growing cultures in a static system. Nevertheless, long-term suppression of bacterial growth was achieved with levels of polymyxin B and colistin that can be attained during therapy, whereas sulphomethylpolymyxins had little effect on bacterial growth even on prolonged exposure.


Electron spin resonance studies of an animal model of human congenital myotonia: increased erythrocyte membrane fluidity in rats with 20,25-diazacholesterol-induced myotonia. Electron spin resonance experiments have been performed on erythrocyte membranes from rats with myotonia induced by treatment with 20,25-diazacholesterol. The results suggest that erythrocyte membranes in this animal model of human congenital myotonia possess a highly significantly increased surface membrane fluidity compared to that of controls. Alterations in the physical state of membrane proteins were not apparent. These findings, also present in human congenital myotonia [Butterfield, Chesnut, Roses & Appel, 1976, Nature (London) 263:159; Butterfield, 1977 (Submitted for publication)], strengthen the concepts that increased membrane fluidity is associated with the presence of myotonia and that congenital myotonia may be a diffuse membrane disease.