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S Shaikh

Publications and source records attributed to S Shaikh.

62 records · Page 4Linked to original sources
PubMed1992

Analysis of the T cell receptor (TcR) regions in the NOD, NON and CTS mouse strains define new TcR V alpha haplotypes and new deletions in the TcR V beta region.

We have analyzed the T cell receptor (TcR) V alpha and TcR V beta regions in the spontaneous mouse model for insulin-dependent diabetes mellitus, the NOD mouse, and compared it to the regions in the two sister strains, the NON and CTS strains. Based on restriction fragment length polymorphism analysis the TcR V alpha region in the NOD mouse is essentially identical to that of the SJL/J strain. In contrast both the NON and CTS strains have a unique TcR V alpha haplotype. Whereas the NOD and NON strains apparently contains all the TcR V beta genes, the CTS mouse has three deletions in the V beta region. Our analysis does not give any indications for the diabetic phenotype of the NOD mouse.

Animals↗
PubMed1991

Dietary risk factors associated with acute and persistent diarrhea in children in Karachi, Pakistan.

Feeding practices may have an important impact on diarrheal diseases in developing countries. This study evaluated feeding practices in three groups of male children aged 6-36 mo: 100 with persistent diarrhea (PD), 79 with acute diarrhea (AD), and 86 in a comparison group (CG). The children came from comparably poor socioeconomic settings in Karachi, Pakistan, except that the literacy rates were higher in mothers of the CG (P = 0.0001). Although greater than 95% of all infants were breast-fed, delayed initiation of breast-feeding was more common in the diarrhea groups. Children with diarrhea were also more likely to receive supplemental milk (PD = 92%, AD = 87%) than were children in the CG (69%, P less than 0.05). Feedings were not withheld during diarrhea but changes were made in the nature of foods given. These results indicate that several feeding practices may be important risk factors for diarrhea in Pakistan.

Acute Disease↗
PubMed1991

A traditional diet as part of oral rehydration therapy in severe acute diarrhoea in young children.

Recently, the role of feeding as treatment of acute diarrhoea has received increasing attention. To assess the efficacy of early feeding in acute diarrhoea, we conducted a randomised, clinical trial of a traditional legume-based weaning diet khitchri in boys 9 to 48 months old with moderate to severe dehydration. Khitchri is composed of rice and lentils cooked with cottonseed oil. Children were randomly allocated to 2 groups: group A received only WHO ORS but no food for the first 24 hours and then khitchri and half-strength cow's milk formula freely; group B received khitchri and the half-strength formula in addition to ORS after the initial rehydration period of 4 to 6 hours. The mean period of evaluation was 3 days. 69 patients were admitted into the study, 33 in group A and 36 in group B. The initial mean purging rate for the children was greater than 200 g/kg/day. Six children did not complete the study because they developed intercurrent infections or were removed by their parents for non-medical reasons. Of the 63 patients who were evaluated, 44 (70%) were successfully treated, 21 in group A and 23 in group B. There were no significant differences in the 2 groups in mean stool output, number of stools, or weight gain, although a trend toward earlier improvement was seen in group B. These data indicate that early feeding of khitchri and WHO/ORS may be as well tolerated as WHO/ORS alone in the first 24 hours treatment of severe acute diarrhoea in young children.

Acute Disease↗
PubMed1984

The specificity of ketanserin in the inhibition of serotonin-induced steroidogenesis in the rat adrenal zona glomerulosa.

Although the biological effects of ketanserin were originally attributed to its specific interaction with serotonin type 2 (5HT2) receptors, at high doses (greater than 10(-8)M) it also appears to act as an alpha 1-antagonist in some tissues. This in vitro study examines the possibility that Ketanserin may inhibit serotonin-induced steroidogenesis by blockade of alpha 1-receptors. Rat zona glomerulosa cells prepared by collagenase digestion of adrenal capsular tissue were incubated at 37 degrees C in Krebs-Ringer bicarbonate buffer (0.2% glucose, 0.2% bovine serum albumin) for 30 min with increasing doses of serotonin (10(-9)-10(-6)M) alone or in the presence of ketanserin (10(-6)M), methysergide (a 5HT-receptor antagonist) 10(-6)M) or prazosin (an alpha 1-antagonist)(10(-6)M). Cyclic AMP, Corticosterone and aldosterone outputs were measured by radioimmunoassay. Serotonin produced correlative sigmoidal dose responses for cyclic AMP, corticosterone and aldosterone which were inhibited by ketanserin and methysergide but not by prazosin. These results suggest that ketanserin does not act by alpha 1-blockade in the adrenal zona glomerulosa but rather as a specific 5HT-receptor antagonist.

Adrenal Cortex↗
PubMed1982

Effects of taxol and nocodazole on insulin secretion from isolated rat islets of Langerhans.

Taxol, a promotor of microtubule polymerization, and nocodazole, which induces microtubule depolymerization, used at concentrations known to be specific for these effects in other cell types, were each shown to inhibit glucose-stimulated insulin secretion from isolated rat islets of Langerhans. These findings suggest that the dynamic regulation of microtubule polymerization-depolymerization in pancreatic B cells may be important for insulin secretion via the microtubule-microfilamentous system.

Alkaloids↗
PubMedDate not supplied

Differential effects of ozone on lung epithelial lining fluid volume and protein content.

Urea dilution has been used to estimate the volume of epithelial lining fluid (ELF) in the respiratory tract. However, ELF volume may be overestimated as the result of rapid net diffusion of urea from tissues into the bronchoalveolar lavage (BAL) fluid. This study established a protocol for rat BAL in a manner that minimizes this problem and then used this procedure to examine the edemagenic effects of ozone (O3) exposure on ELF volume and the concentrations of ELF protein and albumin. One passage lavage with variable dwell times up to 30 s showed no difference in recovered urea, protein, and albumin and ELF volume between 0 and 4 s, but a progressive increase of each thereafter. The calculated concentrations of protein and albumin in ELF did not vary significantly with dwell time. By increasing the number of lavage passages from one to three, the amounts of recovered urea, protein, and albumin and estimated ELF volume were increased with each passage. Again, the calculated concentrations of protein and albumin in ELF did not vary appreciably. When a single lavage passage and no added dwell time were used, it was observed that exposure of rats to 2 but not 0.5 and 1 ppm O3 increased urea, protein, and albumin in the BAL immediately after 6 h exposure. In addition, at 18 h postexposure to 1 ppm O3, ELF volume increased only 21%, but protein and albumin concentrations in ELF were 2.3- and 4.5-fold of control values, respectively. A higher O3 concentration (2 ppm) moderately increased ELF volume (+83%) and exerted even greater effects on concentrations of ELF protein (7.8-fold) and albumin (19-fold) while lower O3 dosage (0.5 ppm) had no significant effect. SDS-PAGE analysis showed that small serum proteins including albumin were greatly enriched in lung BAL fluid of 1 ppm O3-exposed rats. These results demonstrate that movement of water and protein into the airspaces after O3 exposure is not strictly coupled, and that protein recovery by BAL should cautiously be used to indicate airspace edema as a result of O3 injury.

Albumins↗
PubMedDate not supplied

Adjuvant methods in macular hole surgery: intraoperative plasma-thrombin mixture and postoperative fluid-gas exchange.

BACKGROUND AND OBJECTIVE: The optimal method for surgical management of idiopathic macular holes remains unknown. Adjuvant methods including intraoperative cytokines and postoperative fluid-gas exchange with and without laser have been described. We report on the safety and final results of routine intraoperative autologous plasma-thrombin mixture and postoperative fluid-gas exchange when necessary as an adjunct to the surgical therapy of this disease. PATIENTS AND METHODS: A consecutive series of 114 patients (mean age 66.9 years) with primary idiopathic full thickness Stage II, III, and IV macular holes were primarily treated by vitrectomy, fluid/perfluorocarbon gas exchange, and application of autologous plasma-thrombin mixture to the macular hole. Visible epiretinal membranes were peeled but the normal appearing internal limiting membrane was not routinely stripped. Outcome measures included final Snellen visual acuity, rate of macular hole closure, complications, and number of supplemental procedures performed. RESULTS: Closed at one month, were 110 of 121 (91%) macular holes, including two that underwent repeat fluid/gas exchange and laser within the first two weeks after surgery. At the time of final follow-up (mean: 10.9 months), 110 of 121 (91%) macular holes were closed. This included 8 of 9 eyes that had reopening of the macular hole between one and 21 months successfully treated by repeat fluid-gas exchange and 2 eyes that underwent a second successful pars plana vitrectomy, membrane peeling, and repeat fluid-gas exchange. Overall, 98 of 121 eyes overall (81%) were successfully treated by a single surgery; 94 of 121 (78%) achieved two lines or greater of visual improvement; 83 of 121 (69%) achieved 20/70 or better vision; and 47 eyes (39%) achieved 20/40 or better vision. Complications in this series included infectious endophthalmitis (1 eye), intraoperative retinal break (2 eyes), late retinal detachment (5 eyes), transient mild intraocular pressure elevation (46 eyes), inflammatory response (six eyes), epiretinal membrane (6 eyes), intraretinal hemorrhages (1 eye), and cataract (33 of 99 phakic eyes underwent cataract extraction during the follow-up). CONCLUSION: A combination of intravitreal perfluorocarbon gas and autologous plasma-thrombin mixture (tissue glue) was well tolerated in most patients and did not result in any specific long-term complications. The use of supplemental fluid-gas exchange when necessary improved the final success rate. Further well-controlled and randomized studies will be required to determine the efficacy of this as an adjunct or alternative to other methods of treatment for macular holes.

Adult↗