Search PubMed⌕ Search

Biomedical subjects

S Rashid

Publications and source records attributed to S Rashid.

At least 19 recordsLinked to original sources
PubMed2001

Noncommunicable diseases in sub-Saharan Africa: where do they feature in the health research agenda?

There is no doubt that communicable diseases will remain the predominant health problem for the populations in sub-Saharan Africa, including adults, for the next 10-20 years. Concern has been expressed that the available resources to deal with this problem would be reduced by increasing the emphasis on noncommunicable diseases. The latter, however, already present a substantial burden because their overall age-specific rates are currently higher in adults in sub-Saharan Africa than in populations in Established Market Economies. There is also evidence that the prevalence of certain noncommunicable diseases, such as diabetes and hypertension, is increasing rapidly, particularly in the urban areas, and that significant demands are being made on the health services by patients with these diseases. To ignore the noncommunicable diseases would inevitably lead to an increase in their burden; the provision of health services for them would be largely undirected by issues of clinical and cost effectiveness, and their treatment and prevention would be left to the mercy of local and global commercial interests. Improved surveillance of all diseases within sub-Saharan Africa is needed in order to place noncommunicable diseases properly within the context of the overall burden of disease. Research is needed to guide improvements in the clinical and cost effectiveness of resources currently committed to the care of patients with noncommunicable diseases, and to direct and evaluate preventive measures.

Adult↗
PubMed2001

Spatial learning deficits without hippocampal neuronal loss in a model of early-onset epilepsy.

Studies were undertaken to examine the effects recurrent early-life seizures have on the ability of rats to acquire spatial memories in adulthood. A minute quantity of tetanus toxin was injected unilaterally into the hippocampus on postnatal day 10. Within 48 h, rats developed recurrent seizures that persisted for 1 week. Between postnatal days 57 and 61, rats were trained in a Morris water maze. Toxin-injected rats were markedly deficient in learning this task. While these rats showed gradual improvement in escape latencies over 20 trials, their performance always lagged behind that of controls. Poor performance could not be explained by motor impairments or motivational difficulties since swimming speed was similar for the groups. Only eight of 16 toxin-injected animals showed focal interictal spikes in the hippocampus during electroencephalographic recordings. This suggests that learning deficiencies and chronic epilepsy may be independent products of recurrent early-life seizures. A quantitative analysis of hippocampus revealed a significant decrease in neuronal density in stratum pyramidale of experimental rats. However, the differences were largely explained by a concomitant increase in the area of stratum pyramidale. Studies of glial fibrillary acidic protein expression and spread of horseradish peroxidase-conjugated tetanus toxin in the hippocampus suggest that the dispersion of cell bodies in stratum pyramidale can neither be explained by a reactive gliosis nor the direct action of the toxin itself. Taken together, we suggest that recurrent seizures beginning in early life can lead to a significant deficiency in spatial learning without ongoing hippocampal synchronized network discharging or a substantial loss of hippocampal pyramidal cells.

Action Potentials↗
PubMed2001

Triglyceride enrichment of HDL does not alter HDL-selective cholesteryl ester clearance in rabbits.

Triglyceride (TG) enrichment of high density lipoprotein (HDL), which occurs in hypertriglyceridemic states, significantly enhances the rate at which HDL apolipoprotein (apo)A-I is cleared from the circulation of healthy humans. In the New Zealand White (NZW) rabbit, a species naturally deficient in hepatic lipase (HL), TG enrichment of HDL requires prior lipolytic modification to enhance apoA-I clearance. However, the effect of TG enrichment of HDL on the subsequent clearance of HDL cholesteryl ester (CE) has not previously been examined in vivo. Therefore, we investigated, in the NZW rabbit, the effect of ex vivo TG enrichment of rabbit HDL (by incubation with human very low density lipoprotein) on the clearance of HDL CE and apoA-I radiolabeled with (3)H-cholesteryl oleyl ether and with (131)I, respectively. In nine experiments, TG enrichment of rabbit HDL resulted in an 87% average increase in HDL TG and a corresponding 31% reduction in HDL CE content. The calculated apoA-I and CE fractional catabolic rates associated with TG-rich versus fasting HDL tracers were not significantly different (apoA-I: 0.119 +/- 0.017 vs. 0.107 +/- 0.024 pools per h, P = 0.68; CE: 0.147 +/- 0.014 vs. 0.114 +/- 0.019 pools per h, P = 0.20). In an animal model deficient in HL, TG enrichment of HDL did not alter the rates of HDL apoA-I or selective CE clearance. Further studies are needed to determine whether, in the presence of HL, TG enrichment of HDL alters selective HDL CE clearance.

Animals↗
PubMed2001

Web-based e-mail communications: issues in responsive service.

Women's College Hospital (WCH), Toronto, Canada, embarked on a review of 5 years of Web-based e-mail communications to address broad issues of managerial policy and procedure as related to the institution's expanding role in Web-based communication. The hospital looked at who was sending messages, why they were communicating, and how the institution should respond to the new demands placed on them by virtual communicators. The article provides a brief discussion of the results of the review and points out that attention must be given to a broad range of organizational challenges and opportunities posed by such communications. Suggestions related to how health care organizations may respond better to and serve their virtual audiences are offered.

Computer Communication Networks↗
PubMed2001

Wortmannin inhibits platelet aggregation produced by interaction of gamma-aminobutyric acid and the calcium tonophore, A23187.

Platelet aggregation by gamma-aminobutyric acid (GABA) agonists combined with a calcium ionophore was studied. GABA, baclofen and mucimol markedly amplified aggregatory responses to a subthreshold concentration of the ionophore, A23187. This effect was inhibited by wortmannin, a blocker of phosphoinositide 3-kinase. However, several antagonists of GABA receptors had no effect on the response, and benzodiazepines inhibited aggregation. These results suggest that the GABA effect is not mediated by traditional neuronal GABA receptors. We propose that wortmannin inhibits aggregation at a nexus downstream from membrane mechanisms triggered by the GABA-A23187 interaction.

Androstadienes↗
PubMed2001

Comparison of clinical and laparascopic features of infertile women suffering from genital tuberculosis (TB) or pelvic inflammatory disease (PID) or endometriosis.

OBJECTIVE: The objective of the study was to analyze the clinical and laparoscopic features, which may help to differentiate between infertility in females due to Genital Tuberculosis from Pelvic Inflammatory Disease (PID) and Endometriosis. METHODS: This case control study was carried out in a teaching tertiary care hospital. Medical records were searched from 1st January 1987 to 31st December 2000 and 43 infertile women with biopsy proven genital tract tuberculosis were found. Equal number of infertile females with diagnosed PID and Endometriosis were randomly selected. Comparisons were done between features of Genital Tuberculosis with PID and Endometriosis separately and also genital tuberculosis with combined controls of PID and Endometriosis. RESULTS: Patients with genital tuberculosis commonly had primary infertility. PID and Endometriosis patients had early menarche and increased duration of menstruation. On physical examination, patients with Genital Tuberculosis were found to have short heights. No significant findings were observes in the pelvic examination and menstruation history between the comparison groups. Laparascopic examination revealed that fallopian tubes were abnormal, tortuous, bilaterally blocked and thickly adherent more commonly in Genital Tuberculosis when compared to other groups. CONCLUSION: The primary infertility patients with chronic malnutrition and massive adhesive fallopian tubes on laproscopic examination should be evaluated for genital tuberculosis.

Adolescent↗
PubMed2000

Effect of JTT-501 on net hepatic glucose balance and peripheral glucose uptake in alloxan-induced diabetic dogs.

JTT-501, a new insulin sensitizer, improves peripheral glucose uptake in insulin-resistant animals such as KK-Ay mice and Zucker fatty rats. However, the effect of JTT-501 on hepatic glucose metabolism has not been addressed. To investigate this effect, experiments were performed on 6 alloxan-diabetic dogs. Three experiments were conducted for each dog: the treatment experiment, which followed a 10-day oral treatment with JTT-501 30 mg x kg(-1) x d(-1), and 2 control experiments 2 weeks before and 2 weeks after the treatment experiment. A hyperinsulinemic-hyperglycemic clamp was performed with the tracer dilution method (intraportal insulin infusion rate, 18 pmol x kg(-1) x min(-1)). Arterial hyperglycemia (approximately 10 mmol/L) was maintained by adjusting the peripheral glucose infusion rate. After a 45-minute basal period (period I), portal glucose infusion (22.2 micromol x kg(-1)min(-1)) was administered for 120 minutes (period II). This was followed by a 90-minutes recovery period (period III). JTT-501 increased insulin-stimulated glucose utilization (P < .05) and enhanced insulin-mediated suppression of glucose production (P < .05) in periods I and III. Net hepatic glucose balance (NHGB) determined by the arterial-venous (A-V) difference method was increased by JTT-501 in period II (P < .01). We conclude that JTT-501 enhances both hepatic and peripheral insulin sensitivity and therefore may have important therapeutic effects in type 2 diabetes.

Alloxan↗
PubMed2000

Hypertension prevalence and care in an urban and rural area of Tanzania.

OBJECTIVE: To describe the prevalence, detection, treatment and control of hypertension in an urban and rural area of Tanzania. DESIGN: Two linked cross-sectional population-based surveys. SETTING: A middle-income urban district of Dar es Salaam (Ilala) and a village in the relatively prosperous rural area of Kilimanjaro (Shari). PARTICIPANTS: Seven hundred and seventy adults (> 15 years) in Ilala and 928 adults in Shari were studied. RESULTS: Hypertension prevalence (blood pressure > or = 140 and/or 90 mmHg, or known hypertensives receiving anti-hypertensive treatment) was 30% (95% confidence interval, 25.1-34.9%) in men and 28.6% (24.3-32.9%) in women in Ilala, and 32.2% (27.7-36.7%) in men and 31.5% (27.8-35.2%) in women in Shari. Age-standardized hypertension (to the New World Population) prevalence was 37.3% (32.2-42.5%) among men and 39.1% (34.2-44.0%) in women in Ilala, and 26.3% (22.4-30.4%) in men and 27.4% (24A-30.4%) in women in Shari. In both areas, just under 20% of hypertensive subjects were aware of their diagnosis, approximately 10% reported receiving treatment and less than 1% were controlled (blood pressure < 140/90 mmHg). Hypertensive subjects were older, had greater body mass indices and waist: hip ratios, and had more risk factors for hypertension and its complications (smoking, heavy alcohol consumption, physical inactivity, obesity and diabetes) than non-hypertensives. CONCLUSIONS: There is a high prevalence of hypertension in rural and urban areas of Tanzania, with low levels of detection, treatment and control. This demonstrates the need for cost-effective strategies for primary prevention, detection and treatment of hypertension and the growing public health challenge of non-communicable diseases in Sub-Saharan Africa.

Adolescent↗
PubMed2000

Adaptations in beta-adrenergic cardiovascular responses to training in older women.

To determine whether endurance exercise training can alter the beta-adrenergic-stimulated inotropic response in older women, we studied 10 postmenopausal healthy women (65.4 +/- 0.9 yr old) who exercised for 11 mo. Left ventricular (LV) function was evaluated with two-dimensional echocardiography during infusion of isoproterenol after atropine. Maximal O(2) consumption increased 23% in response to training (from 1.35 +/- 0.06 to 1.66 +/- 0.07 l/min; P = 0.004). Training had no effect on baseline LV function, end-diastolic diameter, LV wall thickness, or LV mass. The increase in LV systolic function in response to isoproterenol was unaffected by training. Furthermore, neither the systolic shortening-to-end-systolic wall stress relationship nor the end-systolic wall stress-to-end-systolic diameter relationship during isoproterenol infusion changed with training. We conclude that older postmenopausal women can increase their maximal O(2) consumption with exercise training without eccentric LV hypertrophy or enhancement of beta-adrenergic-mediated LV contractile function. These observations provide an explanation for the finding that maximal cardiac output and stroke volume are not increased in older women in response to training.

Adaptation, Physiological↗
PubMed2000

Beta-blockade, but not normoglycemia or hyperinsulinemia, markedly diminishes stress-induced hyperglycemia in diabetic dogs.

Stress-induced hyperglycemia can lead to significant deterioration in glycemic control in individuals with diabetes. Previously, we have shown in normal dogs that, after intracerebroventricular (ICV) administration of carbachol (a model of moderate stress), increases in both the metabolic clearance rate (MCR) of glucose and endogenous glucose production (GP) occur. However, in hyperglycemic diabetic dogs subjected to the same stress, the MCR of glucose does not increase and glycemia therefore markedly deteriorates because of stimulation of GP. Our aims were to determine the following: 1) whether insulin-induced acute normalization of glycemia, with or without beta-blockade, would correct glucose clearance and prevent the hyperglycemic effect of stress, and 2) whether hyperinsulinemia per se could correct these abnormalities. Stress was induced by ICV carbachol in 27 experiments in five alloxan-administered diabetic dogs subjected to the following protocols in random order: 1) basal insulin infusion (BI) to restore normoglycemia; 2) basal insulin infusion with beta-blockade (BI+block); 3) normoglycemic-hyperinsulinemic clamp with threefold elevation of insulin above basal (3x BI); and 4) normoglycemic-hyperinsulinemic clamp with fivefold elevation of insulin above basal (5 x BI). The BI+block protocol fully prevented stress-induced hyperglycemia, both by increasing MCR (deltaMCR at peak: 0.72 +/- 0.25 ml x kg(-1) x min(-1) vs. no change in BI, P < 0.05) and by diminishing the stress-induced increment in GP observed in BI (deltaGP at peak: 3.72 +/- 0.09 micromol x kg(-1) x min(-1) for BI+block vs. 14.10 +/- 0.31 micromol x kg(-1) x min(-1) for BI, P < 0.0001). In contrast, 3x BI and 5x BI treatments with normoglycemic-hyperinsulinemic clamps proportionately increased basal MCR at baseline, but paradoxically were not associated with an increase in MCR in response to stress, which induced a twofold increase in GP. Thus, in alloxan-administered diabetic dogs, stress increased GP but not MCR, despite normalization of glycemia with basal or high insulin. In contrast, beta-adrenergic blockade almost completely restored the metabolic response to stress to normal and prevented marked hyperglycemia, both by limiting the rise in GP and by increasing glucose MCR. We conclude that acute normalization of glycemia with basal insulin or hyperinsulinemia does not prevent hyperglycemic effects of stress unless accompanied by beta-blockade, and we speculate that short-term beta-blockade may be a useful treatment modality under some stress conditions in patients with diabetes.

Adrenergic beta-Antagonists↗