Search PubMed⌕ Search

Biomedical subjects

V K Sharma

Publications and source records attributed to V K Sharma.

At least 289 records · Page 16Linked to original sources

Contact sensitization by pesticides in farmers.

30 farmers with contact dermatitis and 20 controls were patch tested with a series of locally used pesticides. Allergic reactions to 1 or more pesticides were seen in 11 patients but none of the controls. Carbamates (maneb, carbofuran, carbaryl) were the most frequent sensitizers (7 patients), followed by organophosphorus compounds like: malathion and oxydemton methyl (4 patients); 2,4-dichlorophenoxyacetic acid and fenvalerate (3 patients each); streptocycline (2 patients). Irritant reactions to captaf were seen in 4 patients, thiobencarb weedicide in 3, and organophosphorus compounds in 3. Pesticides should be patch tested in all farmers with contact dermatitis.

Adult↗

Anti-infective factors in preterm human colostrum.

Feeding of the infection prone preterm neonate with concentrated immunologically active ingredients in the form of colostrum may have even more significant clinical implications than in the full term infants. The scarcity of knowledge on anti-infective factors in colostrum of mothers delivering prematurely prompted us to carry out this study. Colostrum was collected and analysed from 25 mothers delivering prematurely (Study group) and 10 delivering at term (Control group). Major anti-infective factors namely IgA, IgG, IgM, lactoferrin and lysozyme were quantitated and total cell, macrophage, lymphocyte and neutrophil counts were performed. The mean concentrations of IgA, lysozyme and lactoferrin of preterm colostrum were significantly higher than in full term colostrum (p less than 0.001). IgG and IgM were found to be similar in both groups. The absolute counts of total cells, macrophages, lymphocytes and neutrophils were found to be significantly higher in the preterm colostrum as compared to the full term colostrum (p less than 0.001). Though in both the groups IgA was the predominant immunoglobulin, the mean percentage of IgA in the study group was significantly higher as compared to the control group. Degree of prematurity did not have any influence on the anti-infective protein levels in colostrum. However total cells and macrophages were significantly higher in colostrum of mothers delivering severely preterm babies.

Adult↗

Sulphaphenazole, streptomycin and sulphaphenazole combination, trimethoprim, and erythromycin in the treatment of chancroid.

One hundred and thirty six patients with chancroid were treated with four different treatment regimens; (A) Sulphaphenazole 1 g 12 hourly by mouth x 10 days (B) Inj streptomycin 1 g intramuscularly daily with sulphaphenazole 1 g 12 hourly orally x 10 days; (C) trimethoprim 200 mg 12 hourly by mouth x 7-10 days, and (D) erythromycin 500 mg 6 hourly orally x 7-10 days. Cure rates of 9% with sulphaphenazole alone, 48% with streptomycin and sulphaphenazole combination, 93% with trimethoprim and 100% with erythromycin were obtained. Sulphaphenazole alone or in combination with streptomycin were thus inferior in the treatment of chancroid. There is need for modification of treatment regimens recommended for chancroid in the textbooks of dermatology and venereology. Trimethoprim can be recommended as first line of treatment for chancroid in developing countries like India where resistance to trimethoprim is uncommon and erythromycin is suggested as a second line of therapy because by that time syphilis can be easily ruled out.

Administration, Oral↗

Spatial heterogeneity of intracellular Ca2+ concentration in nonbeating guinea pig ventricular myocytes.

The spatial distribution of intracellular Ca2+ concentration was determined by fluorescent digital imaging microscopy in fura-2-loaded quiescent cardiac myocytes isolated from guinea pig ventricle. Fluorescent ratio images revealed discrete as well as clustered bright fluorescent spots ("hot spots"), which occupied approximately 20-50% of an individual cell's area. The fluorescent intensity and the area of the hot spots were increased by agents that deplete Ca2+ in the sarcoplasmic reticulum, namely, ryanodine (20-40 nM) and caffeine (5-15 mM). However, when cells were exposed to agents that deplete mitochondrial Ca2+, such as the protonophore, carbonyl cyanide m-chlorophenyl-hydrazone (CCCP, 100-300 nM), or the inhibitor of electron transport, antimycin A (4-40 nM), the fluorescent intensity and the area of the hot spots were reduced. These results indicate that the spatial distribution of intracellular Ca2+ concentration in the ventricular myocytes of guinea pig is quite heterogeneous. The ability of CCCP and antimycin A, but not of caffeine and ryanodine, to reduce the fluorescent intensity in the hot spots implies that Ca2+ compartmentation in the mitochondria is largely responsible for the intracellular Ca2+ heterogeneity seen in the present study.

Animals↗

Renal brushborder membrane vesicle. Study of marker enzymes and uptake of nutrients in Mycobacterium leprae infected mice.

The renal brush border membrane vesicles (BBMV) were used to elucidate the early biochemical functional status during the course of experimental M. leprae infection in mice. The activities of the characteristic brush-border enzymes viz: alkaline phosphatase, leucine amino peptidase and gamma-glutamyl transpeptidase were found to be significantly decreased (p less than 0.001) at 3 and 6 months after infection. The transport of nutrients viz: D-glucose, L-alanine, L-lysine and L-aspartate across BBMV showed similar pattern. The activity of brush border enzymes and transport of nutrients across the membrane returned to normal at 9 months post-infection suggesting regeneration of the brush border membrane.

Alkaline Phosphatase↗

Can aluminium phosphide poisoning cause hypermagnesaemia? A study of 121 patients.

Aluminium phosphide (ALP) poisoning is one of the major causes of death in northern India. It is the commonest mode for suicide. The present study includes 121 patients of proven ALP poisoning. The age varied between 20 and 45 years, and the majority (95) were females. Clinical manifestations were nausea and vomiting in all the patients, dyspnoea and palpitation (78 each), cyanosis (65), hypotension (43) and shock (57). Cardiac arrhythmias were present in 96 cases and hypermagnesaemia in 51 patients. The mean serum total magnesium level (1.94 +/- 0.29 mEq/l) was significantly (p less than 0.01) elevated compared to the mean total magnesium level in control subjects (1.62 +/- 0.26 mEq/l). There was a significantly greater rise in serum magnesium in patients with severe toxicity compared to patients with mild to moderate toxicity. Out of 121 cases studied, 86 died; 76 died within 24 h of ALP ingestion. Mortality was commoner (45 out of 57) in patients with severe toxicity.

Adult↗

Can dietary magnesium modulate lipoprotein metabolism?

In a randomized, single-blinded, controlled study (430 patients aged 25-63 years, 394 males), 214 subjects were administered a magnesium-rich diet and 216 subjects were administered a usual diet for 12 weeks. Age, sex, body weight, hypertension, diabetes, hyperlipidemia, smoking, obesity, diuretic therapy and hypomagnesemia were comparable between the two groups as were laboratory data at entry to the study. The intervention group A received a significantly higher amount of dietary magnesium (1,142.0 +/- 225 mg/day) compared to group B which received the usual diet (438 +/- 118 mg/day). After 12 weeks, there was a significant decrease in total serum cholesterol (10.7%), low-density-lipoprotein (LDL) cholesterol (10.5%) and triglyceride (10.1%) in group A compared to the values at entry to the study; no such changes were evident in group B subjects. HDL-cholesterol showed a marginal mean decrease of 0.8 mg/dl in group B and 2.0 mg/dl increase in group A. However, in hypomagnesemic patients (26 cases) of the intervention group, there was a 10.9% increase in high-density-lipoprotein (HDL) cholesterol in association with a decrease in other lipids. Although a general blood-lipid-reducing effect of a high-fiber, low-cholesterol diet cannot be excluded, dietary magnesium may have contributed to the reduction of total serum cholesterol, LDL-cholesterol, and triglyceride as well as to the marginal rise in HDL-cholesterol. More studies with a longer follow-up are needed in order to confirm the role of magnesium in preventing a decrease in HDL-cholesterol in association with reduction in other lipoproteins.

Adult↗

Antipsychotic pimozide is a potent Ca2+ channel blocker in heart.

The diphenylbutylpiperidine (DPBP) antipsychotic pimozide was identified as a potent new Ca2+ channel antagonist in heart. In whole-cell patch-clamp experiments, pimozide blocked Ca2+ current through L type channels of rat ventricular myocytes, in a voltage-dependent manner. At holding potentials positive to -40 mV, approximately 90% of current was blocked by 200 nM pimozide. Nearly half of this block, 48 +/- 5% (mean +/- SE, n = 5), was relieved by 5-min hyperpolarization to -100 mV. In quin2-loaded myocytes, pimozide blocked 50 mM KCl-induced increases in intracellular Ca2+ concentration [( Ca2+]i) half maximally at a concentration of 75 +/- 15 nM (n = 5). Two other DPBPs, penfluridol and fluspirilene, also blocked the KCl-induced response at similar concentrations. The contractile force of cardiac tissue was also depressed by pimozide. One micromolar pimozide reduced twitch tension in rat papillary muscles by an average of 36 +/- 8% (n = 3). These results demonstrate that the DPBPs comprise a potent new class of Ca2+ antagonists in heart, which will be useful in studying cardiac Ca2+ channels. They also suggest that these agents may have therapeutic value outside the field of psychiatry.

Aminoquinolines↗

Acid-fast bacilli in semen; correlation with bacterial index.

Thirty multibacillary patients (12 LL, 18 BL) were historically reviewed and clinically assessed for evidence of testicular involvement. The bacterial index (BI) of the patients ranged from 1+ to 6+; the morphological index (MI), from 0% to 3%. Nine (30%) patients had oligospermia, while acid-fast bacilli (AFB) were demonstrable in the semen of 3 (10%) patients (2 LL, 1 BL). There was a significant correlation between the BI and the demonstration of AFB in semen (p less than 0.01).

Adolescent↗

Perturbations of intracellular calcium distribution in kidney cells by nephrotoxic haloalkenyl cysteine S-conjugates.

The Ca2(+)-sensitive dye fura-2 was used to investigate the disturbances in intracellular Ca2+ concentration [( Ca2+]i) and distribution induced by the nephrotoxic cysteine S-conjugate S-(1,2-dichlorovinyl)-L-cysteine (DCVC) and its homocysteine analog S-(1,2-dichlorovinyl)-L-homocysteine (DCVHC) in LLC-PK1 cells. After 24-hr treatment with DCVC, the average [Ca2+]i increased from 88 +/- 23 nM to 415 +/- 92 nM. Digital image analysis revealed that the mitochondrial region, which was stained with rhodamine-123, contained lower Ca2+ concentration ([Ca2+]) than other cell areas. This distribution was different from the higher [Ca2+] in the nuclear and mitochondrial regions observed in control cells. In DCVHC-treated cells, there was also an increase in [Ca2+]i to 355 +/- 85 nM, but the increase in [Ca2+] was greater in the mitochondrial region, compared with the rest of the cell. After 72-hr treatment with DCVC or DCVHC, the average [Ca2+]i was 410 +/- 85 nM and 340 +/- 90 nM, respectively, and blebs with markedly higher [Ca2+] (600-1000 nM) than the rest of the cell appeared in both DCVC- and DCVHC-treated cells. Moreover, in DCVC-treated cells the mitochondria could not be stained with rhodamine-123, indicating severe mitochondrial damage and loss of membrane potential. All changes described above took place in viable (propidium iodide-negative) cells. The experiments demonstrate that severe perturbations of intracellular Ca2+ distribution, particularly in the mitochondrial region, precede bleb formation and cell death in the course of development of toxicity by DCVC and DCVHC.

Animals↗

Demonstration of a direct inhibitory effect of cyclosporine on normal human T-cells with two novel models of T-cell activation as probes.

Two novel models of activation of human peripheral blood quiescent T-cells (T-cells) were utilized herein as probes to analyze the mechanisms and to locate the site of action of cyclosporine (CsA) in the T-cell activation pathway. Highly purified T-cells were activated, independently of accessory cells, with either crosslinked anti-CD2 + anti-CD3 monoclonal antibodies (mAbs) or with sn-1,2-dioctanoylglycerol (DAG) and ionomycin. CsA inhibited the expression of 55-kDa interleukin-2 receptors (IL-2R) and T-cell proliferation in these accessory cell-independent models of T-cell activation. Recombinant IL-2, over a wide range of concentrations that included different binding affinities of cellular receptors for IL-2, did not completely reverse CsA-associated inhibition of IL-2R expression and/or proliferation. In additional experiments, designed to examine early activation related events, CsA did not interfere with the increase in intracellular free calcium concentration initiated with anti-CD2, anti-CD3, anti-CD2 + anti-CD3 mAbs or with ionomycin. DAG-induced and PKC-activation-dependent down-regulation of cell surface expression of CD3 antigens was similarly unaffected by CsA. Our findings unambiguously indicate that CsA has a direct inhibitory effect on T-cells. Moreover, CsA's cellular site of action is distal to calcium mobilization and PKC activation but proximal to IL-2R expression and IL-2-dependent DNA synthesis in normal human T-cells.

Antigens, Differentiation, T-Lymphocyte↗

Condylomata lata of the eyelids.

A patient with secondary syphilis and extensive condylomata lata on the face, neck, axillae, groins, and genitalia is described. His facial condylomata lata affected the eyelids, medial canthus, nasolabial folds, angles of the mouth, and chin. Condylomata lata of the eyelids has not been described previously.

Adult↗

Bacillaemia in leprosy and effect of multidrug therapy.

Twenty-five patients of bacilliferous leprosy (17 LL, 8 BL) were studied by the modified haemolysis method for occurrence of bacillaemia and its clearance after two multidrug therapy regimens. Acid-fast bacilli were found in 76% of all patients and in 88.2% LL and 50% BL patients. Bacillaemia occurred with significantly reduced frequency in patients with type II reaction. Acid-fast bacilli were demonstrable in peripheral blood after 1 month in one patient on MDT of an Indian Working Group and 3 lepromatous patients on WHO multidrug therapy. However, bacillaemia could not be demonstrated in any patients after 2 and 3 months of treatment with both regimens.

Adolescent↗

Radiation therapy alone and in combination with bleomycin and 5-fluorouracil in advanced carcinoma esophagus.

This presentation is a randomized prospective study of 74 patients of squamous cell carcinoma of esophagus divided into two groups. First group was treated with radical radiation alone and the other with radical radiation and combination of bleomycin and 5-FU. Analysis at the end of two years showed that the patients treated with addition of chemotherapy had an overall survival of 23 percent as compared to nine percent in the radiation alone group (P less than 0.05).

Adult↗