Examining the role of community resilience and social capital on mental health in public health emergency and disaster response: a scoping review

The ability of the public to remain psychologically resilient in the face of public health emergencies and disasters (such as the COVID-19 pandemic) is a key factor in the effectiveness of a national response to such events. Community resilience and social capital are often perceived as beneficial and ensuring that a community is socially and psychologically resilient may aid emergency response and recovery. This review presents a synthesis of literature which answers the following research questions: How are community resilience and social capital quantified in research?; What is the impact of community resilience on mental wellbeing?; What is the impact of infectious disease outbreaks, disasters and emergencies on community resilience and social capital?; and, What types of interventions enhance community resilience and social capital?A scoping review procedure was followed. Searches were run across Medline, PsycInfo, and EMBASE, with search terms covering both community resilience and social capital, public health emergencies, and mental health. 26 papers met the inclusion criteria.The majority of retained papers originated in the USA, used a survey methodology to collect data, and involved a natural disaster. There was no common method for measuring community resilience or social capital. The association between community resilience and social capital with mental health was regarded as positive in most cases. However, we found that community resilience, and social capital, were initially negatively impacted by public health emergencies and enhanced by social group activities.Several key recommendations are proposed based on the outcomes from the review, which include: the need for a standardised and validated approach to measuring both community resilience and social capital; that there should be enhanced effort to improve preparedness to public health emergencies in communities by gauging current levels of community resilience and social capital; that community resilience and social capital should be bolstered if areas are at risk of disasters or public health emergencies; the need to ensure that suitable short-term support is provided to communities with high resilience in the immediate aftermath of a public health emergency or disaster; the importance of conducting robust evaluation of community resilience initiatives deployed during the COVID-19 pandemic.

Acute Budd-Chiari syndrome caused by inferior vena cava compression from a congenital diaphragmatic hernia

Acute Budd-Chiari syndrome is a rare condition characterised by obstruction of hepatic venous outflow. We describe the case of a 52-year-old man, with a congenital Morgagni diaphragmatic hernia, who presented with acute onset abdominal pain, shortness of breath, lactic acidosis, hyperbilirubinaemia and transaminasaemia. Computed tomography revealed strangulation of the diaphragmatic hernia and extrinsic compression of the inferior vena cava from the herniated viscera. Emergency surgery was carried out to repair the hernia with a biosynthetic mesh, with complete resolution of the Budd-Chiari syndrome.

TP1-4 In vitro induced cytokine response of astrocytes modelling conditions in human traumatic brain injury

Objectives

The objective of this study was to investigate how in vitro astrocyte cultures respond to cytokine pro- and anti-inflammatory cytokine concentrations, corresponding to those seen in the aftermath of human TBI, by analysing downstream cytokine generation.

Design

In vitro study.

Subjects

Human induced pluripotent stem cells (iPSC)-derived astrocytes.

Methods

The astrocytes were exposed to levels of TNF (1–10,000 pg/ml), IL-6 (100–1,000,000 pg/ml), Interleukin-1β (IL-1β, 1–10,000 pg/ml), Interleukin-4 (IL-4, 1–10,000 pg/ml) and Interleukin-10 (IL-10, 1–10,000 pg/ml). Following 24, 48 and 72 hours, culture supernatant was extracted and analysed using a human cytokine/chemokine 39-plex luminex assay (ThermoFisher).

Results

The astrocyte secretome revealed concentration-, time- or concentration*time-dependent production of downstream cytokines (12, 8 and 2 cytokines, respectively p<0.05). IL-1β and TNF exposure generated the most downstream cytokine production, while IL-6, IL-4 and IL-10 did not generally induce a robust response.

Conclusions

iPSC-derived astrocytes exposed to cytokine concentrations reflecting those in TBI generate an increased downstream cytokine production, especially when exposed to IL-1β and TNF. This is in contrast to our previous work on neuronal cultures where IL-1β only produced a few down-stream cytokines.1 More work is needed to better understand how different cells in the CNS respond to the neuroinflammatory milieu after TBI alone and in combination.

Clinical trial design in the neurocritical care unit

Clinical trials provide a robust mechanism to advance science and change clinical practice across the widest possible spectrum. Fundamental in the Neurocritical Care Society's mission is to promote Quality Patient Care by identifying and implementing best medical practices for acute neurological disorders that are consistent with the current scientific knowledge. The next logical step will be to foster rapid growth of our scientific body of evidence, to establish and disseminate these best practices. In this manuscript, five invited experts were impaneled to address questions, identified by the conference organizing committee as fundamental issues for the design of clinical trials in the neurological intensive care unit setting.

Electron Microscopic Observations of Rabbit Antibodies

Electron micrographs were obtained showing the individual, shadow-cast macromolecules from solutions of purified anti-p-azobenzoate rabbit antibody and of normal gamma-globulin. The two materials look alike and consist mainly of asymmetrical rod-like particles about 30 to 40 A in diameter. Lengths are not constant but the weight average is about 250 A for the antibodies and about 200 A for the gamma-globulin. The average observed dimensions are reasonably consistent with values deduced from physical-chemical methods, although the shape is more nearly that of a cylindrical rod rather than the ellipsoid employed in hydrodynamical theory. Mixtures of antibody and specific dihaptenic dye were examined in attempts to establish the mode of the specific aggregation. At the high dilutions necessary for electron microscopy (0.1 mg./ml.), the effect of the dye was small and tended to be masked by non-specific aggregation on drying. The evidence suggests that under these conditions the specific reaction involves an end-to-end aggregation of the elementary particles to produce a weight average length about twice that of the pure antibody.

Psychiatric side effects of ofloxacin used in the treatment of pelvic inflammatory disease

The Clinical Effectiveness Group of the Medical Society for the Study of Venereal Diseases and the Association of Genitourinary Medicine published guidelines on the management of pelvic inflammatory disease in 1999. Subsequently, the use of ofloxacin has increased in our department. However, ofloxacin can cause serious psychiatric side effects, particularly in those with a past psychiatric history. This is of relevance to genitourinary medicine (GUM) physicians as there is a high prevalence of psychiatric illness amongst patients attending GUM clinics. We present two cases of ofloxacin causing severe psychiatric symptomatology, in one case causing an acute psychotic reaction. It is recommended a psychiatric history is taken prior to prescribing ofloxacin and that consideration is given to alternative therapy for those with previous psychiatric illness.

Diminished levels of the putative tumor suppressor proteins EXT1 and EXT2 in exostosis chondrocytes

The EXT family of putative tumor suppressor genes affect endochondral bone growth, and mutations in EXT1 and EXT2 genes cause the autosomal dominant disorder Hereditary Multiple Exostoses (HME). Loss of heterozygosity (LOH) of these genes plays a role in the development of exostoses and chondrosarcomas. In this study, we characterized EXT genes in 11 exostosis chondrocyte strains using LOH and mutational analyses. We also determined subcellular localization and quantitation of EXT1 and EXT2 proteins by immunocytochemistry using antibodies raised against unique peptide epitopes. In an isolated non-HME exostosis, we detected three genetic hits: deletion of one EXT1 gene, a net 21-bp deletion within the other EXT1 gene and a deletion in intron 1 causing loss of gene product. Diminished levels of EXT1 and EXT2 protein were found in 9 (82%) and 5 (45%) exostosis chondrocyte strains, respectively, and 4 (36%) were deficient in levels of both proteins. Although we found mutations in exostosis chondrocytes, mutational analysis alone did not predict all the observed decreases in EXT gene products in exostosis chondrocytes, suggesting additional genetic mutations. Moreover, exostosis chondrocytes exhibit an unusual cellular phenotype characterized by abnormal actin bundles in the cytoplasm. These results suggest that multiple mutational steps are involved in exostosis development and that EXT genes play a role in cell signaling related to chondrocyte cytoskeleton regulation.

Prolongation of survival by parabiosis in strain 129 dystrophic mice

Dystrophic mice were joined in parabiosis with normal partners of the same sex and strain. Their survival and the progress of the characteristic signs was compared with single controls, both normal and dystrophic. Comparisons between the size of certain organs were made. The usual brief survival of dystrophic mice was much prolonged by parabiosis, and the characteristic signs were often much reduced in severity. Adrenals were proportionately larger and kidneys smaller in single dystrophic mice as compared with normal controls. In contrast with normals the kidneys were also smaller in male dystrophic mice than in females. However parabiotic dystrophic mice had kidneys which were proportionately larger than in normal animals. The survival was often limited by the induction of cardiovascular disease, apparently as a consequence of parabiosis.

Photosynthetic energy storage in aquatic leaves measured by photothermal deflection

In a study of photosynthetic energy storage efficiency (ES), the adaxial surface of the leaves of Vallisneria americana exhibited the highest ES values (22%) of the four aquatic plants examined. V. americana leaves have a dispersed structure and it was possible to measure the energy storage properties of the epidermal cells independently of the rest of the leaf. The abaxial epidermis had a higher value of ES at zero light fluence than the adaxial epidermis but ES in the abaxial epidermis declined much more rapidly with light fluence. Thus the abaxial epidermis is more suited to lower light fluences than the adaxial epidermis. ES declined as the pH rose from 4.0 to 8.0 at a constant dissolved inorganic carbon concentration. This paralleled the change from carbon dioxide to bicarbonate and suggests that these leaves utilise CO2 more efficiently than bicarbonate. ES increased by about 50% at pH 8.0 as leaf sections further from the leaf tip were examined which demonstrates that the older epidermal cells are less well able to use bicarbonate. Exposure to 30 min of a saturating light fluence caused the epidermal chloroplasts to move from the periclinal walls to the anticlinal walls. This decreased the photothermal signal by increasing the thermal diffusion distance and lowering the light fluence due to greater chloroplast shading. The latter effect increased ES. It appears that chloroplast movement could assist the epidermis to survive harmful light fluences.

Effects of the protein kinase C stimulant bryostatin 1 on the proliferation and colony formation of irradiated human T-lymphocytes

The protein kinase C stimulant bryostatin 1 (Bryo) was used in examining human peripheral blood T-lymphocyte radiosensitivities in proliferation assays. Bryo was similar to PMA in inducing T-cell proliferation by the CD3, CD28 and CD69 pathways. No difference in radiosensitivities was observed in T-cells stimulated by the three independent surface antigen-mediated activation pathways. CD3 was chosen as the second signal for comparing the potencies of the three different first signals Bryo, phorbol 12-myristate, 13-acetate (PMA), and interleukin 2 (IL-2) in stimulating T-cell proliferation and in maintaining this response after radiation. Though there were radioresponse differences among various individuals, the irradiated lymphocytes consistently showed significantly greater proliferation when treated with Bryo or PMA than with IL-2 (p < 0.05- < 0.005). No difference in proliferative responses was observed in T-cells irradiated between 4 h before and 15 h after the addition of stimulants. Colony forming assays showed higher colony survival for irradiated T-cells stimulated with Bryo than with PMA. These results support the important role of protein kinase C in T-cell radiation responses, and suggest a potential role for Bryo in enhancing T-lymphocyte survival during radiation therapy.

DNA repair in the genomic region containing the beta-actin gene in xeroderma pigmentosum complementation group C and normal human cells

The limited DNA excision repair in UV-irradiated fibroblasts from xeroderma pigmentosum complementation group C (XP-C) occurs in selected chromatin regions. The small beta-actin gene (3.5 kb) is one of these and is repaired as part of a large region (about 50 kb). We show here that only one of the DNA strands is repaired through this extended region. Several genomic fragments spanning about 70 kb in the beta-actin region have been cloned and mapped and some have been examined for repair activity. Both strands of one fragment (14 kb) in the immediate vicinity of the gene are repaired. Transcripts associated with both strands are detected. In normal cells, both strands of the same fragment are preferentially repaired relative to the genome overall and also associated with transcription. The repair activity in XP-C cells associated with other defined DNA fragments indicates that termini for the repaired regions in either strand can be located. Results are consistent with those of others indicating that transcription promotes repair in XP-C cells and that several levels of repair activity, at least one coupled to transcription, occur in normal cells. We conclude that the beta-actin repair domain, defined in XP-C cells, comprises both strands of a small region (about 14 kb) in the vicinity of the beta-actin gene and a single strand extending through a larger region of about 50 kb. We suggest that a similar genomic organization for repair exists in normal cells.

Experimental transmission of bovine viral diseases by insemination with contaminated semen or during embryo transfer

Three experimental approaches were used to study transmission of blue tongue (BT), infectious bovine rhinotracheitis (IBR) and bovine virus diarrhoea (BVD) viruses. These were insemination with contaminated semen, experimental infection of embryo donor cows, or transfer of embryos experimentally exposed to virus in vitro to normal recipients. Parameters assessed included number and quality of embryos produced, virus detection (isolation and electron microscopy), serology and histopathology. All superovulated sesceptible cows inseminated with semen containing blue tongue virus (BTV) (n = 2) or infectious bovine rhinotracheitis virus (IBRV) (n = 2) became infected. One cow inseminated with semen containing BTV produced seven virus-free seven-day-old embryos; the second cow failed to produce any embryos. One of two cows inseminated with semen containing IBRV produced two underdeveloped, virus-free embryos while no embryos were produced by the second cow. One of two cows inseminated with semen containing bovine viral diarrhoea virus (BVDV) became infected. Two poorly developed, virus-free seven-day-old embryos were recovered from one of these cows. Superovulated susceptible cows inoculated either intramuscularly with BTV (n = 3) or intranasally with IBR virus (n = 2) became infected. Virus was isolated from some tissues of two BTV-infected cows, neither of which produced embryos. A third BTV-infected cow produced two virus-free embryos collected at necropsy five days after inoculation. One of two cows experimentally infected with IBR virus, produced three embryos but virus was not detected either by electron microscopy (1 embryo) or in cell culture by cytopathic alterations (1 embryo).(ABSTRACT TRUNCATED AT 400 WORDS)

Effect of pregnancy on the immune response of cattle to a Brucella vaccine

An experiment was performed to determine whether humoral- or cell-mediated immune responses of cattle to a Brucella abortus vaccine were influenced by the stage of gestation. Heifers were vaccinated 2 mth before and 2 mth after breeding with cell envelopes of B. abortus in an oil adjuvant containing trehalose dimycolate and muramyl dipeptide. Control groups received adjuvant alone or no vaccine. Following breeding, vaccinated animals were divided into pregnant and nonpregnant subgroups. Immune responses to two outer membrane proteins were measured at monthly intervals by ELISA and lymphocyte blastogenesis tests. Skin tests were performed during the ninth month of gestation. Vaccination induced sustained immune responses, but few differences were detected between pregnant and non-pregnant animals. The relative increase in IgA antibodies to group 3 protein in nonpregnant heifers exceeded that in pregnant heifers during months 4 and 6 of gestation (P less than 0.05). Dermal hypersensitivity, measured by changes in double skin thickness, was significantly greater in nonpregnant heifers to porin (P less than 0.01) and group 3 (P less than 0.05) antigens at 24 h post-injection, but no significant differences in skin thicknesses or in the nature of the lesions were observed at 48 h. Animals which received adjuvant alone demonstrated negligible responses. Pregnancy had no significant effect on the responses of lymphocytes to phytohemagglutinin (PHA) or Concanavalin A (Con A). However, plasmas from nonvaccinated pregnant heifers taken during the sixth and seventh (but not eight or ninth) months of pregnancy decreased responses of normal donor cells to PHA and Con A when compared with those in autologous plasma (P less than 0.05).

Hypertensive potency of 18-oxocortisol in the rat

The hypertensogenic effect of 18-oxocortisol, an aldosterone analogue possessing both mineralocorticoid and glucocorticoid properties, was studied at the same dosage but under different experimental conditions in two experiments. Under experimental conditions conducive to the development of mineralocorticoid hypertension (i.e., rats with a single kidney on a high NaCl intake), there was an extremely rapid onset of saline polydipsia and hypertension accompanied by cardiac and renal enlargement, marked thymic involution without adrenal atrophy, cardiovascular lesions, and hypokalemia. With the exception of the thymic changes, the same changes occurred in rats given the biologically equivalent dose of deoxycorticosterone acetate. Under circumstances favoring the development of glucocorticoid hypertension (i.e., intact rats on a normal sodium intake), the same dose had only a transient blood pressure-elevating effect, attaining prehypertensive levels at most, and caused neither chronic hypertension nor hypokalemia. The biologically equivalent glucocorticoid dosage of cortisol was similarly ineffective. Under these circumstances, both steroids caused thymus involution but only 18-oxocortisol caused kidney enlargement.

Rhinoviruses in Seattle families, 1975-1979

Rhinovirus infections in Seattle families with schoolchildren (1975-1979) and in selected outpatients were revealed by virus shedding or antibody rise. These observations extend those in the Seattle Virus Watch (1965-1969). Analysis of rhinovirus serotype prevalence again revealed certain "common" persisting serotypes but provided no further evidence that new serotypes are continuing to emerge. Two seasonal peaks, spring higher than fall, were again evident. Infection rates, again inversely related to age, were lower overall than in the Virus Watch (0.42 vs. 0.64 per person-year), probably because there were fewer young children. Frequencies of antibody response by virus shedders again varied widely by serotype but differed greatly from those in the Virus Watch in rank order of response rate, suggesting that immunogenicity is not a stable serotype characteristic. The frequency and magnitude of antibody response of virus shedders increased with age. Antibody-related protection against infection was evident only in persons age greater than or equal to 10 years. Observations in 7 families during successive homotypic infection episodes indicate that postinfection immunity to natural challenge requires persistence of antibody. Of all reported respiratory illness, 11.9% (0.31 per person-year) were due to rhinoviruses and 6.9% to influenza viruses. Of viruses recovered from family members, rhinoviruses, herpes simplex, and influenza comprised 56%, 12.6%, and 12.4%, respectively. Although households often experienced greater than or equal to 2 concurrent or closely consecutive episodes of infection with different viruses, only 29 individuals were shown to shed 2 viruses at the same time. Most of the second viruses, include 3 rhinoviruses and 18 other nonhemadsorbing viruses, appeared when 582 rhinovirus-positive specimens were retested after treatment with homotypic antibody. These results suggest that rhinoviruses interfere with nonhemadsorbing viruses in cell culture but mostly with other rhinoviruses in humans.

Augmented depression and reduced excitability of the central nervous system (CNS) by cadmium in the rat

Reports indicating that low doses of cadmium caused vasodilation, but that larger quantities elicited a pressor response, apparently mediated by a CNS reflex, prompted an examination of cadmium-induced changes in CNS responsiveness and activity. Rats were injected intraperitoneally with either 2 mg/kg or 4 mg/kg of CdCl2 solution, after which the CNS was either depressed by pentobarbital or excited by strychnine at different dose levels. Cadmium treatment, administered before pentobarbital, decreased the time required for sleep induction and prolonged sleep duration at doses of either 20 mg/kg or 30 mg/kg: at 40 mg/kg only induction was affected and at 60 mg/kg neither was influenced. At a dosage of 60 micrograms/kg, strychnine caused convulsions in all control animals, but in none pretreated with CdCl2. When either 75 or 120 micrograms/kg of strychnine was used, cadmium at either dosage failed to prevent convulsions, although the onset was delayed and duration curtailed. The rapidity with which Cd modified CNS activity indicated that the effect can not depend upon cadmium-induced synthesis of metallothionine, but represents a direct effect of Cd on the CNS. Cadmium treatment did not substantially improve the survival of rats that convulsed when treated with strychnine.

Indium leucocyte imaging in true pyrexia of unknown origin

A patient with pyrexia of unknown origin (PUO) was investigated for a focal infection using autologous indium-labelled leucocytes. Only one site of increased activity was observed; this was asymptomatic and subsequently proved to be an infected nasal sinus. This case highlights the necessity, in PUO investigations, of carrying out whole-body imaging rather than just investigating the areas with presenting symptoms.

Control of spontaneous and deoxycorticosterone-salt hypertension and polyuria by nitrendipine pellets

Weekly subcutaneous implantation of 25-mg nitrendipine pellets prevented onset of both spontaneous and deoxycorticosterone-salt hypertension in rats. Discontinuance of implantation led to reappearance of hypertension after about 2 weeks in the former and led to rising though still normotensive pressures after about 3 weeks in the latter. A new implant caused blood pressures in both to drop within a day or two to normotensive levels in the case of spontaneously hypertensive rats. Nitrendipine prevented cardiac hypertrophy in steroid hypertensive rats, but not in spontaneous hypertensives. A nitrendipine pellet given 1 day before or a 30 mg/kg injection given 1 h prior to the administration of a water, Na+, and K+ load, prevented the diabetes insipidus-like syndrome resulting from deoxycorticosterone-salt treatment, and lowered sodium but not potassium excretion. Nitrendipine did not affect steroid-induced hypernatremia and hypokalemia.

Decreased aldosterone receptor affinity in aortic cells from the Fischer 344 rat

The Fischer 344 rat strain represents a uniform population that is immune to salt induced hypertension and resistant to mineralocorticoid hypertension. We have compared aldosterone binding in aortic cells cultured from salt-resistant Fischer 344 rats to that from salt-sensitive Wistar-Kyoto controls for aldosterone binding. Aortic smooth muscle cells of both strains contain two classes of aldosterone binding sites: corticoid receptor I with high affinity and low capacity and corticoid receptor II with low affinity and high capacity. The corticoid receptor I of Fischer 344 rats has a significantly (P less than 0.001) lower affinity than that of age and sex-matched Wistar-Kyoto controls, but the binding capacity was the same. There was no difference between the strains in the affinity or binding capacity of corticoid receptor II. These results indicate that mineralocorticoid binding may be important in susceptibility and resistance to hypertension and support the contention that mineralocorticoids regulate blood pressure in part by direct action on vascular smooth muscle cells.

Immune response to porin in cattle immunized with whole cell, outer membrane, and outer membrane protein antigens of Brucella abortus combined with trehalose dimycolate and muramyl dipeptide adjuvants

The immune response of cattle to nonliving vaccines derived from Brucella abortus rough strain 45/20 was studied. Vaccines contained trehalose dimycolate and a derivative of muramyl dipeptide. N-acetylmuramyl-L-alpha-aminobutyryl-D-isoglutamine. A factorial experiment was designed to test the effects of type of antigen, quantity of antigen, and quantity of mineral oil on the immune response to porin. Muramyl dipeptide was kept constant at 5 mg per dose, and 1 part of trehalose dimycolate was incorporated for two parts of dry matter. Over a 10-week period, blastogenesis responses to porin were largest in cattle immunized with outer membranes; the highest antibody titers to the porin-lipopolysaccharide complex were achieved by immunization with detergent-extracted outer membrane proteins. There was no advantage in the use of 25, rather than 5, mg of any of the antigens, but antibody responses were improved by increasing the quantity of oil from 0.6 to 1.8 ml per dose. In other animals, blastogenesis and antibody responses were sustained at high levels longer than 3 months after two vaccinations with outer membrane proteins. Intradermal injection of porin evoked inflammatory reactions histologically consistent with delayed-type hypersensitivity. Cross-reactions in cases of delayed-type hypersensitivity occurred with porin derived from a smooth strain of B. abortus but were less extensive than in the blastogenesis test. The magnitude of the delayed-type hypersensitivity and blastogenesis responses induced by vaccination exceeded those observed after natural or experimental infections. No ill effects were observed after vaccination. These findings provide a basis for the use of trehalose dimycolate and muramyl dipeptide adjuvants in evaluating nonviable vaccines for bovine brucellosis.

Influenza surveillance in the Pacific Northwest 1976-1980

Between June 1976 and June 1980 active year-round surveillance for influenza was carried out in Seattle in order to establish an early warning system. This report compares yield by different community groups and age. Waves of influenza virus infection appearing in three successive springs were followed in each instance by epidemics with the same subtype virus(es) in the following winter. These included two co-circulating A/H3N2 variants (A/Victoria/75 and A/Texas/77) in spring 1977 and winter 1977-1978, A/H1N1 (A/USSR) in spring 1978 and H1N1 (A/Brazil) winter 1978-1979, and type B influenza in spring 1979 and winter 1979-1980. Despite intensive surveillance through the summer and fall, the first isolate was not obtained until early December each year. Young adults (18-30) were as good sources for influenza viruses as children (less than 18).

Prevention of spontaneous and glucocorticoid hypertension in rats by nisoldipine

The effect of daily treatment (sometimes interrupted) with the calcium blocker nisoldipine at two different dose levels, one double the other, on the development of spontaneous hypertension in the rat was evaluated. Both doses prevented development of the disorder during daily administration, but when treatment was stopped the same degree of hypertension as in controls quickly developed. Resumption of treatment caused blood pressure to fall to or towards normal again. The higher dose caused a more rapid and greater fall than the lower, and allowed a lesser pressor response when it was discontinued. The drug had no effect on growth, and the only consistent hematological effect was a slight thrombocytosis. Daily treatment at a single dose level slightly reduced normal blood pressure and prevented cortisone hypertension. Serum renin activity was unaffected by nisoldipine but was elevated by cortisone treatment: nisoldipine increased aldosterone levels, but not when cortisone was also given.

Structural, functional and hypertensive effects of 19-oxo-11-deoxycorticosterone acetate (19-oxo-DOCA) in the rat

Mononephrectomized rats were given 1% NaCl solution to drink; half of them received 1 mg/day of 19-oxo-11 deoxycorticosterone acetate (19-oxo-DOCA) in sesame oil subcutaneously and half received only the oil for a period of four weeks. The steroid had no effect upon saline intake, systolic blood pressure, growth or the size of adrenals, hearts or kidneys, although it did produce hypernatremia and hypokalemia. The discrepancy between a demonstrable mineralocorticoid effect without blood pressure elevation awaits elucidation.

Prevention of DOCA-salt hypertension with the calcium blocker nitrendipine

Mononephrectomized female rats on a high sodium intake developed hypertension, hypokalemia, enlarged hearts and kidneys and slight adrenal involution under deoxycorticosterone treatment. Simultaneous administration of nitrendipine (5 mg/kg twice daily) completely prevented hypertension and reduced but did not abolish cardiac enlargement. There was no effect of the calcium slow-channel inhibitor on kidney enlargement, adrenal atrophy or hypokalemia. The ability of the steroid to produce cardiomegaly in the absence of an elevated blood pressure to account for it, tends to confirm the suggestion of other investigators that the steroid may have that effect by a mechanism not involving blood pressure elevation.

Aldosterone binding sites in aortic cell cultures from spontaneously hypertensive rats

Spontaneously hypertensive rats and rats made hypertensive by deoxycorticosterone-salt treatment have in common increased Na+ and K+ permeability and transport in their aortic cells. These changes may be important factors in the development of the hypertensive state and may be mediated by mineralocorticoid binding to intracellular sites in the aorta. Therefore, we examined 3H-aldosterone binding in aortic cell cultures from spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. Vascular corticoid binding sites in the two strains were compared by Scatchard analysis of Kd and Bmax, pH and temperature stability, and subcellular binding. By all of these criteria normotensive rats. These results indicate that the underlying genetic defect in spontaneous hypertension is not an intrinsic cellular defect which alters mineralocorticoid binding in the aorta.

Influenzavirus infections in Seattle families, 1975-1979. I. Study design, methods and the occurrence of infections by time and age

Intensive surveillance of Seattle, Washington, families with school-age children for influenzavirus infections during 1975-1979 encompassed 639 family- and 2732 person-seasons of observation, covering four influenzavirus epidemic seasons: type B (1975-1979), type A/H3N2 (1975-1976 and 1977-1978) and type A/H1N1 (1978-1979). Late spring "herald" waves of infection occurred in 1977 (A/H3N2), 1978 (A/H1N1) and 1979 (type B), the latter presaging an epidemic in 1979-1980. Out-of-season infections, recognized by serology only, included type B and A/H3N2 viruses in each summer and A/H1N1 virus in 1978. In epidemic seasons, infection rates were highest in children aged 5-9 years (A/H3N2) or in teenagers (A/H1N1 and type B). A/H1N1 virus caused the sharpest epidemic, with 31% of the population (but only 2% of adults) infected and 72% of households invaded in 1978-1979. These compare with infection rates of 17-24% overall and 6-13% of adults and the invasion of 38-53% of households observed in the type B and two A/H3N2 epidemics. Extended observation (largely serologic) of a cohort of 1965-1969 Virus Watch families for up to 14 years (including one three-year gap) indicated overall infection rates of 13.7 and 16.4 per 100 person-years with types B and A/H3N2 viruses, respectively, and rates of first and second reinfections of about 3 and 1 per 100 person-years, respectively, with each virus. Close surveillance in 1975-1979 revealed second family episodes of infection with each prevalent virus, 37 with A/H3N2, 15 with type B and 13 with A/H1N1 virus. Risk of infection in these episodes was related more to current hemagglutination-inhibiting titers than to experience (infected or not) in the initial episodes, with 67-100% reinfection when titers were low. Among younger (less than 20 years old) members, related illness was as frequent with reinfection as with initial infection.

Electronic probe measurements of cervico-vaginal mucus for detection of ovulation in dairy cows: sanitation, clinical observations and microflora

An electronic vaginal probe with a sanitizing carrier unit has been designed to measure changes in the electrical resistance of cervico-vaginal mucus in the cow. Over 400 cows and heifers have been probed during the period prior to breeding. When 33 heifers and cows were probed 2-3X per day for 30 days, mild irritation of the vaginal mucosa developed during the luteal phase. In all other studies no grossly detectable lesions or other complications resulting from probing were observed either in experimental herds or in farmer herds where breeding tests were conducted. Fertility of probed cows was equal to cows inseminated when estrus was detected visually. Weekly culture of microorganisms from cervico-vaginal mucus collected from three cows probed 3X per week for 22 days resulted in no detectable change in the population of microorganisms. The number of isolates each successive week was 11, 8, 8 and 5, respectively. The sanitary procedures followed appeared to prevent introduction of organisms of any consequence, as judged by the decreasing number of isolates during the probing sequence.

Mycoplasma bovigenitalium in the upper genital tract of bulls: spontaneous and induced infections

Mycoplasma bovigenitalium, was isolated from vesicular gland secretions of a large proportion of clinically normal pubescent bulls. Infections established at this site in 1 to 2 year old bulls sometimes persisted for over a year, induced a local immune response, and were associated in some animals with unacceptably low motility of sperm following freezing of semen for artificial insemination. Inoculation of as few as 1000 cfu directly into the vesicular gland sufficed to establish infection but the naturally occurring syndrome could not be successfully reproduced by this method. Intratracheal injection of the organism produced infection of the upper genital tract in one of two bulls. The ELISA test was more sensitive than the IHA test in detection of antibodies to M. bovigenitalium in serum or vesicular secretions, but its usefulness was limited by extensive cross reactions with other Mycoplasma species.

Influence of dosage, consciousness, and nifedipine on the acute pressor response to intraperitoneally administered cadmium

The acute pressor effect of intraperitoneally administered cadmium was explored over the dose range 0.015-2 mg/kg in both pentobarbital-anesthetized and conscious rats. The former first respondent at 0.031 mg/kg, and successive doublings of that dosage increased the highest pressures attained in a stepwise fashion until a dosage of 0.25 mg/kg, the maximally effective quantity, was reached. Arterial pressure did not rise in conscious rats until a dose of 1 mg/kg, which gave the maximum response within the range examined. Heart-rate changes with Cd were slight, and rarely significant at a given dosage, but pentobarbital invariably caused tachycardia. Anesthetized rats thus gave a graded response, while conscious animals reacted in an all-or-none fashion. The increased pressor responsiveness of rats under pentobarbital can not be ascribed to its cardiac parasympatholytic effects, since sensitivity was not conferred upon conscious rats when pretreated with atropine at a dose producing even greater tachycardia than that caused by pentobarbital. Nifedipine, which blocks calcium entry into smooth muscle cells, prevented the pressor response to cadmium when given as pretreatment and terminated an ongoing response when give intercurrently. Possible mechanisms to account for the observed behavior are considered.

Similarities and differences between effects of testosterone and 19-nortestosterone in rats, with particular reference to hypertensogenic potency

Both 19-nordeoxycorticosterone and 19-norprogesterone are potent hypertensogens. This particularly interesting in the latter case, since the parent steroid is antimineralocorticoid and antihypertensive. The present experiment compared the ability of testosterone and 19-nortestosterone to cause hypertension in rats. Both steriods caused adrenal atrophy, nephromegaly, relative hypoproteinemia and increased hematocrit, but only testosterone provoked saline polydipsia, hypernatremia, hypertension, cardiomegaly and vascular lesions. It is evident that demethylation of testosterone at C10 completely destroys any effect on sodium metabolism or blood pressure, but leaves certain other pathophysiologic responses, including extreme adrenal atrophy, unimpaired. The hypertensogenic effect of testosterone has been attributed to its inhibitory effect on adrenal structure and function, the latter characterized by an induced enzymatic defect leading to increased secretion of deoxycorticosterone. This raises the intriguing question of whether, despite the comparable involution of the adrenal cortex, there are significant differences in adrenocortical enzymatic changes initiated by the respective androgens, which could account for their quiet different blood pressure effects.

An immunocytochemical study of the cytogenesis of pancreatic endocrine cells in the lizard, Anolis carolinensis

The differentiation of the pancreatic endocrine cells in the lizard Anolis carolinensis following oviposition was examined. Immediately postoviposition (PO) there was no apparent differentiation of epithelioid cells into endocrine or exocrine components. Individual subpopulations of the endocrine-like cells, which could not be identified during the early PO period on the basis of either their tinctorial properties at the light-microscopic level or their granule morphologies at the electron-microscopic level, exhibited specific hormonal localization by peroxidase-antiperoxidase complex immunocytochemistry. All four hormones searched for, insulin, glucagon, somatostatin, and pancreatic polypeptide (PP), were present in epithelioid cells shortly after oviposition. However, the immunostained secretory granules in the early PO period were smaller than those of the adult. Secretory granule morphologies that are typical of the adult were acquired at different times during development. Delta granules were observed first and were followed by alpha granules, and beta granules which appeared shortly before birth. The secretory granules of the PP-containing F cells could not be readily placed within this maturation sequence. Mosaic cells (containing more than one hormone) were not seen. Levels of immunoreactive insulin and glucagon in the pancreas increased several fold from day 10 to day 28 PO, but the attainment of adult beta-granule morphologies did not appear to be directly related to insulin itself. The results show that cytodifferentiation of the anolian endocrine pancreas occurs postoviposition and that immunocytochemical methods can be used to follow an organelle sequence during development. These findings suggest that subcellular organelles undergo structural remodeling during maturation which, at least in the case of secretory granules, may have functional significance.

Inhibition of DOC-salt and adrenal-regeneration hypertension with the calcium blocker nifedipine

When nifedipine was given to rats at a dosage of 0.3 mg/kg, the blood pressure fell and heart rates rose slightly in normotensive controls, but both changes were more marked in rats with DOC-salt hypertension, the magnitude of the drop in mm Hg being progressively greater as hypertension evolved. Tachycardia also tended to increase, but became somewhat erratic once hypertension was established. Both changes were relatively constant and equivalent when expressed as a percentage of the initial value. Nifedipine given by minipump at a dosage of 8 mg/ml proved able to prevent or modulate, adrenal-regeneration hypertension, but not DOC-salt hypertension. However, in the latter, when the pumps were discontinued and a 1 mg/kg/day injection schedule was substituted, blood pressure fell in nifedipine-treated and rose in untreated rats. The latter dosage had a greater effect on blood pressure and heart rate of normotensive rats than 0.3 mg/kg.

Mineralocorticoid and hypertensive effects of 19-nor-progesterone

The mineralocorticoid potency of 19-nor-progesterone was evaluated by both its effect on electrolyte excretion in adrenalectomized animals and its ability to cause hypertension and electrolyte changes in mononephrectomized, salt-loaded rats. The mineralocorticoid activity, measured using an adrenalectomized rat bioassay, indicated that 19-nor-progesterone was 2.5% as potent as aldosterone but did not antagonize the effect of aldosterone when both were administered. In mononephrectomized rats, the daily administration of 1 mg/day quickly caused an enhanced consumption of 1% saline and induced severe hypertension within 3-4 weeks. Some severely hypertensive animals had marked anemia, but other did not; as a group they were found to have hypernatremia and hypokalemia. Hypertensive animals were found during life to display a relative hypothermia and, at necropsy, to have heart and kidney enlargement with severe and extensive vascular lesions in both organs, but not adrenal hypertrophy. It is concluded that 19-nor-progesterone has the characteristics of a potent mineralocorticoid and, as such, is capable of causing hypertension. It is not yet clear why this should be accompanied by hypothermia.

Four hormones in the pancreas of the lizard, Anolis carolinensis

The electron microscopic localization of insulin, glucagon, somatostatin, and pancreatic polypeptide (PP) in the pancreas of the iguanid lizard, Anolis carolinensis was studied by the unlabeled antibody peroxidase-antiperoxidase immunocytochemical technique. Insulin, glucagon, and somatostatin were localized absolutely to those cells previously identified on the basis of the characteristics of their secretory granules as being beta cells, alpha cells, and D cells, respectively. The secretory granule cores of the PP-containing cells appeared to be ellipsoidal with a semi-major axis of 450 nm and a semi-minor axis of 365 nm. This previously unidentified cell type is named the F cell, in keeping with the localization of PP to the original F cell of the canine pancreas. Without immunocytochemical staining, the qualitative ultrastructural characteristics of the F cell secretory granules were inadequate to permit identification of the F cell, especially with regard to the D cell.