PubMed Health⌕ Search

Biomedical subjects

R Downing

Publications and source records attributed to R Downing.

At least 55 records · Page 3Linked to original sources
PubMed1991

Separation of beta-cells from dispersed porcine pancreas by selective lectin binding.

Variation in cell-surface sugar residues which exist between different pancreatic cells has been exploited in an attempt to isolate beta-cells from dispersed porcine pancreas utilizing selective lectin binding. The binding characteristics of a range of lectins were compared to determine their ability to differentiate between endocrine and non-endocrine cells in the porcine pancreas. Histological analysis showed that peroxidase labelled Arachis hypogaea bound selectively to islet cells in Carnoy-fixed sections of pancreas. In five experiments, porcine pancreas was dispersed into single cells by collagenase digestion, incubated with fluorescein isothiocyanate-labelled Arachis hypogaea and analysed using a Fluorescence Activated Cell Sorter. Fluorescein isothiocyanate-labelled Arachis hypogaea bound to a population of cells comprising 6% +/- 4.2% (mean +/- s.d.) of the total. Cells from representative samples were sorted into populations, based on fluorescence. Immunohistochemical analysis of the fluorescent populations showed that 93% +/- 2% of these cells contained insulin: none of the cells stained positive for glucagon or somatostatin. These preliminary studies show that it is possible to separate porcine beta-cells from a dispersed cell preparation using a fluorescent labelled lectin.

Animals↗
PubMed1990

Vascular anomalies of the scalp.

Paediatricians and surgeons of different disciplines are referred vascular anomalies of the scalp from time to time. These rare lesions may produce serious side-effects and the authors review the treatment of these abnormalities illustrated by five cases. Where possible, total excision is the treatment of choice.

Adolescent↗
PubMed1990

AIDS and HIV infection in Uganda--are more women infected than men?

In countries in sub-Saharan Africa, HIV is transmitted primarily heterosexually. HIV infection and AIDS in women not only affects women's health but also has implications for the other members of society. Maternal infection is the source of most childhood HIV infection in Africa and maternal health is a strong predictor of child survival. In Uganda, a review of passive AIDS surveillance has shown almost equal numbers of clinical cases reported in men and women. However, in three population-based HIV serosurveys, women were consistently found to have a higher infection rate (approximately 1.4 times) than men. In addition, both AIDS case surveillance and seroprevalence studies demonstrate an earlier age of presentation and mean age of infection in women. The higher rate of HIV infection in women suggests either differential rates of transmission between women and men, higher rates of female sexual exposure to infected men, or longer survival among HIV-infected women compared with men. Although further studies are required to illuminate both the biology and the epidemiology of heterosexual HIV transmission in Africa, these findings of earlier and higher infection rates in women have important implications for women's health and child survival in Uganda and indicate the need for specially targeted interventions to reduce transmission in this group.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Prognostic factors in acute renal failure following aortic aneurysm surgery.

This study analyses the prognostic factors associated with survival in 70 patients who developed acute renal failure following surgery for an aortic aneurysm. Forty-nine patients (70 per cent) had surgery for a ruptured aortic aneurysm and 21 patients (30 per cent) had an elective procedure. Fifty-nine patients received haemodialysis. Thirty-three patients (47 per cent) survived the episode of acute renal failure. Six of these thirty-three patients died within three months of recovering from acute renal failure, giving an overall survival of 27/70 (39 per cent). A stepwise logistic regression analysis showed that the following factors significantly adversely affected survival: a need for inotropic support, ventilation for more than three days and age over 65 years. A model developed using these variables provided a basis for predicting outcome.

Acute Kidney Injury↗
PubMed1989

A tale of two clinics--primary health care in refugee settings: lessons from Sudan and Somalia.

The elements and techniques of PHC were not developed in and for refugee situations, and the acute needs and transient situation of refugees sometimes attracts a more traditional medical approach. However, as refugees remain in a host country and their situation stabilizes there, attempts are made to convert to PHC. Refugee health programmes face some unique challenges when attempting this transformation, problems that exist even when PHC techniques were present at the onset of the programme. The challenge is to adapt PHC principles for use in acute and chronic refugee situations, and to find ways to develop a community base for health care programmes while at the same time meeting the acute medical needs unique to refugees.

Ambulatory Care Facilities↗
PubMed1989

Risk factors associated with HIV infection in Uganda.

Risk factor data were collected in 1,328 inpatients and outpatients in 1987 in 15 hospitals throughout Uganda; 42% were positive for HIV antibodies by ELISA. Seropositivity was associated with urban residence, sexually transmitted diseases (STD), number of sex partners, and sex for payment or with a person with an AIDS-like illness. Homosexuality and intravenous drug abuse, recognized risk factors in western countries, were not seen as risk factors. By multivariate analysis, urban residence and sex for payment were not independently associated with infection. Among females, number of sex partners, sex with a person with an AIDS-like illness, and numbers of episodes of STDs were significantly associated with seropositivity. In males, similar associations were seen, although number of reported sex partners was not independently associated with infection. These findings support the view that heterosexual contact is the predominant mode of transmission in Uganda and suggest that the main risk factors relate to high-risk heterosexual behavior.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Knowledge, attitudes and practices concerning AIDS in Ugandans.

A survey of the knowledge, attitudes and practices of 3928 Ugandans concerning AIDS was done in two semi-rural communities in August 1987. Eighty-eight per cent of the respondents knew that AIDS could be acquired from other people and that having multiple sexual partners was high-risk behaviour. There were, however, many incorrect beliefs about HIV transmission, including belief in transmission by insect bites (37%), witchcraft (22%) and casual contact with ill people (21%). AIDS was believed to be curable by 15% of the respondents. As part of the survey, blood was obtained from 3907 (99%) participants; 421 (10.8%) had antibody to HIV-1 by enzyme-linked immunosorbent assay (ELISA) and females were more likely to be infected than males (12.5 versus 8.8%, relative risk 1.42). Factors significantly associated with HIV infection on univariate analysis include multiple sexual partners, sexually transmitted diseases (STDs), injections, and being female. Stratified analysis of a history of STDs in people who were monogamous still showed an association with HIV infection. Information about the AIDS epidemic is reaching the Ugandan population; however, changes in behaviour are slower to follow.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Evaluation of the WHO clinical case definition for AIDS in Uganda.

Infections with human immunodeficiency virus are common in areas of the world where laboratory testing and sophisticated diagnostic facilities are unavailable. A World Health Organization clinical case definition for acquired immunodeficiency syndrome was developed in 1985 for use in such areas. In 1987, we tested this definition on 1328 inpatients and outpatients in 15 hospitals throughout Uganda. Five hundred sixty-two patients (42%) were positive by enzyme-linked immunosorbent assay for human immunodeficiency virus antibody. The World Health Organization definition had a sensitivity of 55%, a specificity of 85%, and a positive predictive value of 73%. Modification of the case definition by excluding a known cough from tuberculosis as a minor criteria decreased sensitivity slightly to 52%, but specificity and positive predictive value increased to 92% and 83%, respectively. Amenorrhea, although not specifically asked about, was a symptom noted by many female patients (26% of females who were positive by enzyme-linked immunosorbent assay); as a symptom indicative of human immunodeficiency virus infection, amenorrhea had a specificity of 99%, with a positive predictive value of 89%. These findings support the generalizability of the World Health Organization clinical acquired immunodeficiency syndrome definition and its use (especially the modified version) in areas of Uganda without sophisticated facilities.

AIDS Serodiagnosis↗
PubMed1988

Kaposi's sarcoma in Zimbabwe. II. Peripheral lymphocytes, immunoglobulin G levels and HIV antibody positivity.

Patients with Kaposi's Sarcoma (KS) were grouped according to their clinical symptoms into "indolent", "locally aggressive", "endemic generalised aggressive" and "epidemic generalised aggressive" disease. Only the patients in the epidemic generalised aggressive disease group had serum antibodies to HIV. Complete peripheral blood counts, including lymphocyte subsets, and serum IgG assays were performed on all patients before treatment was initiated. In all the aggressive disease groups there was evidence of immune deficiency in that T helper/inducer (T4) cells were reduced leading to reduced T4,T8 (suppresser/cytotoxic) ratio. All patient groups had increased levels of serum IgG. Although immune deficiency and aggressive KS can be explained in the HIV infected patients no underlying cause has been found in the HIV negative patients with aggressive KS.

HIV Antibodies↗
PubMed1987

Gastric emptying: a study to compare the effects of intrathecal morphine and i.m. papaveretum analgesia.

Gastric emptying was studied in two groups of 10 patients who underwent elective cholecystectomy. The groups were comparable for age, weight and duration of operation. Gastric emptying was measured with a radioisotopic technique using Tc99m-DTPA (diethylene triamine pentaacetic acid) before, and 24 h after, surgery. Analgesia was provided by intrathecal morphine 0.8 mg alone (group A) or by i.m. papaveretum 10 mg, administered as required, plus one additional dose 1 h before the postoperative measurement (group B). Control gastric emptying rates were not significantly different in the two groups (mean +/- SD: A = 76.6 +/- 23.0 ml; B = 81.8 +/- 16.3 ml in 30 min). After surgery, gastric emptying was significantly greater in group A (42.9 +/- 35.6 ml) than in group B (11.0 +/- 27.9 ml) (P less than 0.05).

Adult↗
PubMed1986

Imipramine and chlordiazepoxide in depressive and anxiety disorders. I. Efficacy in depressed outpatients.

We randomly assigned 425 outpatients, independently classified as primarily depressed by two trained psychiatrists, to double-blind treatment with Imipramine hydrochloride, chlordiazepoxide hydrochloride, or placebo. Those patients who remained at least moderately depressed (following a two-week placebo washout period) were treated for an additional eight weeks. An endpoint analysis of 387 patients who completed two or more weeks of medication disclosed early therapeutic advantages of chlordiazepoxide. By week 4 of treatment, however, imipramine produced more improvement than did placebo and chlordiazepoxide. By six and eight weeks a general, marked therapeutic advantage was found for imipramine relative to placebo and to chlordiazepoxide on measures of depression, anxiety, anger-hostility, interpersonal sensitivity, and global improvement. Chlordiazepoxide-treated patients generally did significantly better on sleep difficulty but significantly worse on anger-hostility and interpersonal sensitivity than did imipramine- or placebo-treated patients.

Adult↗
PubMed1986

Imipramine and chlordiazepoxide in depressive and anxiety disorders. II. Efficacy in anxious outpatients.

A double-blind, placebo-controlled comparison at three collaborating university sites included 242 patients diagnosed as having anxiety disorders. A two-week placebo washout period preceded random assignment to eight weeks of imipramine hydrochloride, chlordiazepoxide hydrochloride, or placebo treatment. Antianxiety effects of imipramine were superior to those of the other two agents by the second treatment week; these effects became more clearly significant thereafter and were independent of degree of both baseline depression and anxiety. Excluding patients with possible panic-phobic syndromes from the analyses removed most significant antiphobic and antidepressant effects of imipramine but left intact imipramine's significantly superior antianxiety effects.

Adult↗