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Biomedical subjects

R Sher

Publications and source records attributed to R Sher.

At least 55 records · Page 3Linked to original sources
PubMed1980

In vitro effects of histamine on eosinophil migration.

Histamine at concentrations of 5 X 10(-6) to 5 X 10(-5) M increased eosinophil movement to endotoxin-activated serum (EAS). This effect was due entirely to stimulation of random migration (chemokinesis). Directional motility (true chemotaxis) was inhibited by these concentrations. Regulation of chemotaxis was apparently mediated via an H2 receptor as metiamide, an H2 receptor antagonist, but not diphenylhydramine hydrochloride, an H1 receptor antagonist, blocked the histamine-induced inhibition of chemotaxis. Both histamine and metiamide when used alone had no effect on eosinophil motility. The histamine effects on motility were associated with increased levels of intracellular cAMP, whereas cGMP levels were not affected.

Cell Movement↗
PubMed1980

Production of a suppressor factor by human adherent cells treated with mycobacteria.

Human peripheral blood mononuclear cell (MN) proliferation and lymphokine production induced by mitogen could be inhibited by heat killed whole mycobacteria. The inhibition was induced by a wide variety of mycobacteri but not by other Gram-positive or Gram-negative organisms or by latex particles. Proliferation and lymphokine production by adherent cell-depleted lymphocytes was not inhibited by these organisms. Adherent cells treated with mycobacteria had the ability to inhibit lymphocyte blastogenesis when co-cultured with the lymphocytes. the inhibitory effect of these adherent cells was due to the release of a heat stable, nondialyzable suppressor cells. These latter cells, which were T gamma cells, could inhibit the blastogenic ability of normal lymphocytes activated by mitogens. The results suggest that in situations of high mycobacterial load, adherent cells are activted to release a suppressor factor that will activate lymphocytes to become suppressor cells. This mechanism may explain the anergy associated with lepromatous leprosy or advanced tuberculosis.

Cell Adhesion↗
PubMed1980

The effects of a soluble factor released by sensitized mononuclear cells incubated with S. haematobium ova on eosinophil migration.

Incubation of sensitized mononuclear cells from patients with schistosomiasis with specific antigen containing a suspension of viable Schistosoma haematobium ova resulted in the release of a soluble factor which was chemotactic for eosinophils. Production of this substance was detectable at 24 h and demonstrated peak chemotactic activity after 2 days in culture. The chemotactic potential was dose-dependent and attracted eosinophils obtained from patients with schistosomiasis or allergic diathesis. Human neutrophil motility was unaffected by this chemoattractant. Preliminary studies demonstrated that the chemotactic factor is a heat-stable substance with peak activity associated with a molecular weight of approximately 42,000. These findings may reflect an in vitro correlate of cell-mediated immunity and may indicate a role played by the lymphocyte in the control of eosinophil function in human biology.

Antigens↗
PubMed1979

Overwhelming pneumococcaemia 17 years after splenectomy. A case report.

We present a case of fulminant pneumococcaemia and disseminated intravascular coagulopathy in a young adult man 17 years after splenectomy. The clinical presentation, laboratory and postmortem findings are discussed. The diagnosis, management and prophylaxis of overwhelming infections in splenectomized patients are reviewed. The advent of pneumococcal and other vaccines could contribute significantly to the successful protection of asplenic patients against certain severe infections.

Adult↗
PubMed1978

Staining of eosinophil granulocytes in chemotactic studies.

A fast and reproducible method for the staining of eosinophils on millipore filters for the study of chemotaxis is described. This procedure allows for the easy differentiation of eosinophils from other granulocytes both at the intra-filter level and on the filter surface.

Chemotaxis, Leukocyte↗
PubMed1978

Polymorphonuclear cell function in the various polar types of leprosy and erythema nodosum leprosum.

Polymorphonuclear leukocyte motility, both in vivo and in vitro, and reduction of Nitro Blue Tetrazolium was studied in tuberculoid and lepromatous leprosy patients and a group of lepromatous patients with erythema nodosum leprosum (ENL). A profound defect in random migration, chemotaxis, and chemokinesis was found in lepromatous patients with and without complicating ENL, and marked depletion of skin window migration confirmed these in vitro findings. Tuberculoid patients exhibited a mild defect in polymorphonuclear leukocyte motility. Serum inhibitors of normal polymorphonuclear leukocyte chemotaxis were found in all types of leprosy, but sera from lepromatous and ENL patients were most inhibitory. Resting levels of Nitro Blue Tetrazolium reduction were normal in all three groups. Reconstitution of polymorphonuclear leukocyte cells from normal and ENL patients with ENL serum, however, showed increased Nitro Blue Tetrazolium reduction well above the normal range, whereas reconstitution with normal, lepromatous, and tuberculoid sera failed to increase Nitro Blue Tetrazolium reduction above the normal values.

Chemotaxis, Leukocyte↗
PubMed1977

Immunological studies of eosinophilic gastro-enteritis and treatment with disodium cromoglycate and beclomethasone dipropionate.

A 45-year-old woman with intestinal malabsorption due to eosinophilic gastro-enteritis was found to have markedly fluctuating total serum IgE levels with a positive intradermal skin test and a positive radio-allergosorbent test to milk antigen. No organ-specific or non-organ-specific auto-antibodies were detected in the patient's serum, and her complement profile was normal. Low doses of disodium cromoglycate failed to improve intestinal absorption, whereas a 16-day course of a corticosteroid, beclomethasone dipropionate 3 mg daily, improved D-xylose and carotene absorption without suppressing the hypothalamic-pituitary-adrenal axis.

Beclomethasone↗
PubMed1977

Hepatitis B antigen, hepatitis B antibody, and subtypes in leprosy.

The prevalence of hepatitis B antigen (HBsAg), hepatitis B antibody (HBsAb), and subtypes in 242 cases of leprosy is reported. Patients were divided into three subgroups, lepromatous (174), tuberculoid (55), and borderline (13). A total of 131 patients were tested on admission; the remaining 111 had been institutionalized for a period of 3 months or more when tested. Of the 131 cases tested on admission, 88 were retested 6 to 12 months after admission. There was no statistical difference in the incidence of HBsAg and HBsAb among the three groups or between normal controls and the leprosy patients. The predominant subtype was ADW (84.1%). After institutionalization, one lepromatous case converted to HBsAg positive and four converted to HBsAb positive.

Antibodies, Viral↗
PubMed1976

Defective neutrophil motility in children with measles.

The random migration and chemotactic ability of neutrophils from ten patients with uncomplicated measles was found to be grossly impaired when compared to a group of normal children. Chemotaxis to endotoxin activated serum and to hydrolysed casein was markedly depressed, but serum from measles patients, when activated by endotoxin, generated and chemotactic activity and did not contain leukotactic inhibitors. The defect in neutrophil motility was confirmed in vivo by abnormal Rebuck skin windows. The defect was temporary, and recovery of normal chemotaxis was observed by the eleventh day after the onset of the rash.

Cell Movement↗
PubMed1976

T and CR+ lymphocyte profile in leprosy and the effect of treatment.

Thymus-derived lymphocytes (T lymphocytes) and complement receptor-bearing lymphocytes (CR+ lymphocytes) were estimated by using erythrocyte rosettes and erythrocyte-antibody-complement rosettes as markers in untreated lepromatous and untreated tuberculoid patients and in healthy controls. Treated lepromatous cases were also investigated. Ten cases of untreated lepromatous patients were reassessed 6 months or more after therapy commenced. A significant decrease in both percentages and absolute numbers of CR+ cells in the untreated lepromatous leprosy subjects was observed. This decrease showed a return to normal levels after treatment. The percentage of T cells in the untreated lepromatous cases was normal; however, the absolute numbers of T cells and the total lymphocyte count showed a significant decrease. After therapy, the T cell population was unchanged but the total number of lymphocytes increased significantly with treatment. The absolute number of T and CR+ cells was significantly less in the untreated than in the treated lepromatous patients.

Blood Cell Count↗
PubMed1976

Serum immunoglobulin levels in White and Black patients with virus-A and-B hepatitis.

Serum immunoglobulin G, M and A levels were measured in 106 White patients with acute virus-A (hepatitis-B surface antigen-negative) hepatitis and 27 White patients with acute virus-B (hepatitis-B surface antigen-positive) hepatitis and compared with the values previously obtained in Black patients with these diseases. The mean serum IgM level in the White patients with virus-A hepatitis was significantly higher than that in virus-B hepatitis (p less than 0,001). This difference was much more obvious than that in Black patients, mainly due to a much lower mean serum IgM response in Black patients with virus-A hepatitis. The reason for the blunted IgM response in Black patients with virus-A hepatitis is not known, but it may be related to a difference in the reaction against altered host tissues rather than any difference in antibody production against the virus per se. The mean serum IgG and IgA levels were not significantly different in the White patients with virus-A and virus-B hepatitis and they were lower than the corresponding figures in Blacks.

Adolescent↗
PubMed1976

Isolation of human eosinophils and their lymphocyte-like rosetting properties.

A method for the isolation of large numbers of almost pure human eosinophils from peripheral blood using hypague-ficoll density gradients, gelatin sedimentation and carbonyl iron is described. Eosinophils were obtained from patients with parasitic infections, allergic reactions, undiagnosed eosinophilias and normal volunteers. Erythrocyte (E) and erythrocyte-antibody-complement (EAC) rosettes were formed by a number of eosinophils.

Cell Separation↗
PubMed1976

Distribution of waste anesthetic gases in the operating room air.

Epidemiologic and animal studies identify a strong relationship between chronic exposure to anesthetic gases and health hazards. Efforts to reduce exposure of personnel require an understanding of the distribution of anesthetic waste gases in the operating room air. Concentrations of nitrous oxide and halothane were measured at numerous stations throughout an operating room and a delivery room in the absence of personnel. Air conditioning flow rates and flow patterns were varied, as was the height of the anesthetic gas source. Air flow patterns were found to dominate the anesthetic gas distribution, while buoyancy effects were negligible. Venting waste gases at the floor does not significantly reduce exposure of personnel. Areas of high concentration were observed; their occurrences and locations varied strongly with air flow patterns. The exhaust grille is the best location for a single measurement of the average room concentration. Recirculating air-conditioning systems reduce energy costs; however, only the non-recirculating portion of the air exchanges reduces waste gas concentrations.

Air↗
PubMed1975

Outbreake of Marburg virus disease in Johannesburg.

The first recognised outbreak of Marburg virus disease in Africa, and the first since the original epidemic in West Germany and Yugoslavia in 1967, occurred in South Africa in February 1975. The primary case was in a young Australian man , who was admitted to the Johannesburg Hospital after having toured Rhodesia. Two secondary cases occurred, one being in the first patient's travelling companion, and the other in a nurse. Features of the illness included high fever, myalgia, vomiting and diarrhoea, hepatitis, a characteristic maculopapular rash, leucopenia, thrombocytopenia, and a bleeding tendency. The first patient died on the seventh day from haemorrhage resulting from a combination of disseminated intravascular coagulation and hepatic failure. The other two patients were given vigorous supportive treatment and prophylactic heparin and recovered after an acute phase lasting about seven days. During this period on developed pancreatitis, the serum amylase remaining raised until the 32nd day after the onset of the illness. The other developed unilateral uveitis after having been asymptomatic for two months. This persisted for several weeks and Marburg virus was cultured from the anterior chamber of the eye.

Adult↗