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Biomedical subjects

S Gupta

Publications and source records attributed to S Gupta.

At least 1,531 records · Page 85Linked to original sources

Autologous mixed lymphocyte reaction in man: XV. Cellular and molecular basis of deficient autologous mixed lymphocyte response in insulin-dependent diabetes mellitus.

The autologous mixed lymphocyte response (AMLR) and the allogeneic mixed lymphocyte response were deficient in a subset of patients with newly diagnosed insulin-dependent diabetes mellitus (IDDM). Using a single set of HLA-identical twins, the cellular and molecular basis of deficient AMLR was investigated and appears to be due to a defect in both responder T cells and stimulator non-T cells. Interleukin-2 production was diminished in the patient but not in the healthy twin. The in vitro addition of purified interleukin-2 enhanced the depressed AMLR in the diseased twin. This suggests that the deficient AMLR in IDDM may be in part due to a deficiency in the production of interleukin-2.

Adolescent↗

Comparison of QRS score and treadmill performance for assessing ventricular function after myocardial infarction.

QRS score as a means to assess left ventricular ejection fraction (LVEF) following acute myocardial infarction (AMI) has been developed recently and its significance confirmed by various studies. Similarly, the value of maximal treadmill exercise test as a means to assess functional capacity is well known. The present study was done to determine if there is any correlation between QRS score and treadmill exercise performance. Twenty patients with AMI, 3 months after the event, were studied. No significant correlation was observed in terms of duration of exercise (r = -0.007, p = 0.48) or magnitude of ST segment depression (r = 0.015, p = 0.475). QRS score denotes the resting LVEF while exercise-induced ischemia produces changes in dysfunctioning myocardium. These two tests denote different parameters and a judicious combination of both is suggested to assess patients following AMI.

Electrocardiography↗

Focal renal cortical necrosis associated with zomepirac.

Anaphylactoid shock, disseminated intravascular coagulation, and anuric renal failure requiring dialysis occurred in a patient receiving zomepirac sodium for toothache. Although renal function showed gradual improvement after seven days of anuria, the recovery was slow and incomplete. Renal biopsy three weeks after the onset of renal failure revealed evidence of focal renal cortical necrosis. Association of zomepirac administration with renal cortical necrosis is not known to have been previously demonstrated. This observation adds another dimension to the previously reported renal complications of nonsteroidal anti-inflammatory agents, especially zomepirac. The proportions of lymphocyte subsets, as defined with monoclonal antibodies, and the proliferative response to mitogens were normal. The patient's lymphocytes showed no proliferative response to zomepirac. Serum complement components and immunoglobulin levels were within normal limits, and radioallergosorbent testing gave negative results. The mechanism of anaphylactoid reaction to zomepirac in this case, therefore, remains unclear.

Analgesics↗

High-performance hydrophobic interaction chromatography of proteins.

A new, weakly hydrophobic, high-performance liquid chromatography column has been developed for the separation of native proteins based on their relative hydrophobicities. Starting with a covalently bound, hydrophilic polyamine matrix, packing materials were synthesized through acylation with anhydrides and acid chlorides of increasing chain length to obtain increasingly hydrophobic surfaces. Proteins in aqueous buffers were induced to bind hydrophobically to the columns by the use of high salt concentrations in the mobile phase. Elution was achieved by decreasing the ionic strength of the solvent in a linear gradient. A mixture of cytochrome c, conalbumin, and beta-glucosidase was used as a standard to test the resolving power of newly synthesized columns. On a 4-cm butyrate column, baseline resolution was achieved in 20 min with a gradient of 3.0 mu sodium sulfate in 0.1 M potassium phosphate buffer, pH 7.0, to water. The static loading capacity for each column was determined using a hemoglobin binding assay. Capacities normally ranged between 150 and 180 mg of hemoglobin per gram of support. Since proteins are not denatured in hydrophobic interaction chromatography, enzymes eluted from the column retained enzymatic activity. Samples of alpha-amylase and beta-glucosidase ranging in size from 10 to 200 micrograms were recovered from the butyrate column with greater than 92% enzymatic activity in all cases. In a single trial, the enzyme citrate synthase was recovered from the benzoate column with 92% retention of enzymatic activity.

Chemical Phenomena↗

Autologous and allogeneic mixed-lymphocyte responses following thermal injury in man: the immunomodulatory effects of interleukin 1, interleukin 2, and a prostaglandin inhibitor, WY-18251.

A group of 30 burn patients with 36-87% total body surface area (TBSA) burns was studied at 24-48 hr postburn. These included studies of (1) autologous and allogeneic mixed-lymphocyte reactions (MLR); (2) the immunoregulatory influence of mitomycin C-treated T cells, non-T cells, and unfractionated peripheral blood lymphocytes (PBL) on allogeneic MLR; and (3) correlation between the proportions of T-cell subsets defined with monoclonal antibodies (OKT4 and OKT8) and autologous MLR. Studies concerning adherent cell production of thromboxane, prostaglandin E2, and prostaglandin F2a and the immunomodulatory effects of Interleukin 1 (IL-1), Interleukin 2 (IL-2), and a prostaglandin inhibitor, WY-18251, on autologous MLR are presented. The autologous mixed-lymphocyte reaction was depressed in 60% of the burn patients tested. This depressed response correlated closely to the extent of third-degree injury (P less than 0.025) and to TBSA injury greater than 60% (P less than 0.025). A linear correlation was observed between the depression in autologous MLR and a decrease in both the percentage of OKT4+ T cells and the OKT4+/OKT8+ ratio. The response of T cells from burn patients in allogeneic MLR was normal. Age, sex, TBSA of the burn, and size of second-degree burn did not correlate with the abnormalities observed in MLR. Mitomycin C-treated mononuclear cells, purified T cells, or non-T cells from burned patients did not demonstrate any suppressive influence on MLR in normals. Monocyte number and arachidonic acid metabolism were investigated. In addition to increased numbers of monocytes following thermal injury, adherent cells produced increased quantities of thromboxane, prostaglandin E2, and prostaglandin F2a. The effects of Interleukin 1, Interleukin 2, and a prostaglandin inhibitor, WY-18251, were studied in autologous MLR (AMLR) of burned and normal patients. Interleukin 1 and WY-18251 did not induce any significant changes in proliferation in burned patients or normal controls. When compared to cultures without exogenous IL-2, an increase in AMLR was observed following the addition of IL-2 to burn patient cultures at Day 6 and Day 7 of culture. Although the addition of IL-2 did increase proliferation in AMLR of normal controls at Day 6 and Day 7, the enhancement observed for the burn patient cultures represented a restoration to the level of normal control cultures without IL-2. A dose-dependent increase in AMLR was observed in T cells isolated from normal and burned patients in the presence of purified Interleukin 2.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Deficiency of monoclonal antibody (Leu 7) defined NK cells in newly diagnosed insulin-dependent diabetes mellitus.

Peripheral blood from 11 newly diagnosed patients with insulin-dependent diabetes mellitus (IDDM) was studied for the proportion of monoclonal antibody (HNK 1, Leu 7) defined natural killer (NK) cells using a fluorescence-activated cell sorter analyzer. The proportion of Leu 7+ cells in patients with IDDM (7.0 +/- 4.0) was significantly (P less than 0.001) lower than in simultaneously studied healthy controls (16.8 +/- 7.0). A 2-yr-old boy with recent onset IDDM had a deficiency of Leu 7+ NK cells (6.1%), while his healthy identical twin had normal proportions of Leu 7+ cells (22.2%), when compared to a simultaneously studied healthy control. Two patients reexamined in remission and one other studied in remission alone, showed deficiency of Leu 7+ NK cells. This study demonstrates a quantitative deficiency of monoclonal antibody (Leu 7+) defined NK cells in newly diagnosed patients with IDDM that persists during remission of the disease and therefore appears to be independent of metabolic abnormality. The deficiency of NK cells may predispose genetically susceptible individuals to viral-induced islet cell injury, contributing to the pathogenesis of IDDM.

Adolescent↗

Evaluation of acute toxicity of carbaryl and malathion to freshwater teleosts, Channa punctatus (Bloch) and Heteropneustes fossilis (Bloch).

Bioassay tests evaluated the acute toxicity of carbaryl (a carbamate) (50% wettable powder, W.P.), and malathion (50% E.C.) (an organophosphate) (50% emulsifiable concentrate; E.C.) by determining their LC50 and the acute toxic ranges for 24, 48 and 72, and 96-h exposure to Channa punctatus (Bl.) and Heteropneustes fossilis (Bl.). Regression equations and slope functions were determined for different time periods. The relative susceptibility of the fish, the relative toxicity, and the safe concentrations of these biocides were calculated on the basis of LC50 for 96 h. C. punctatus was found to be relatively more susceptible to both the compounds, while malathion was the more toxic of the two biocides.

Animals↗

Acute toxicity of vegetable oil factory effluent to some freshwater teleosts in relation to size.

Specimens of Cirrhina mrigala (Ham.), Labeo rohita (Ham.) and Channa punctatus (Bl.) falling in the size (total length) range of 5.5 +/- 1.0 cm to 27.0 +/- 2.0 cm were exposed to different concentrations of the vegetable oil factory effluent for evaluating the influence of size on the acute toxicity of the factory effluent. The results suggest that relative toxicity of the effluent decreased with increase in the size of the fish. However, for specimens exceeding 20.0 +/- 1.6 cm in size, the toxicity of the effluent increased with an increase in size of the fish. The results also indicate that C. mrigala was most susceptible, while C. punctatus was least susceptible to the effluent.

Animals↗

3,5-dibromo-2'-chloro-4'-isothiocyanato salicylanilide in the control of Hymenolepis nana in rats--a pilot study.

The efficiency of a new anticestode compound, 3,5-dibromo-2'-chloro-4'-isothiocyanato salicylanilide (GUPTA et al. 1980) for mass eradication of hymenolepiasis from rat colonies was assessed in a pilot study. The drug was administered with milk or food. For effective eradication, depending on the size of animals, single or multiple doses of 100 to 500 mg of the drug/kg body-weight, mixed in milk, or 50 mg/kg in feed were necessary. Better results were obtained when the compound was given in feed as it ensured effective consumption irrespective of the seasonal variations. The efficacy of the compound was also assessed on cysticercoids in intermediate hosts (Tribolium confusum) by feeding them on flour medicated at 5%, 1% and 0.1% levels. None of the concentrations killed the larvae or arrested their development.

Animals↗

Syntheses and anthelmintic activity of alkyl 5(6)-(substituted-carbamoyl)- and 5(6)-(disubstituted-carbamoyl)benzimidazole-2-carbamates and related compounds.

A number of alkyl 5(6)-(substituted-carbamoyl)- and 5(6)-(disubstituted-carbamoyl)benzimidazole-2-carbamates and related compounds have been synthesized, and their anthelmintic activity against various intestinal helminths of experimental animals have been evaluated. A large percentage of the compounds synthesized showed noteworthy activity against Ancylostoma ceylanicum and at higher doses against Hymenolepsis nana infections. Compared to the alkyl 5(6)-(substituted-carbamoyl)benzimidazole-2-carbamates, the disubstituted carbamoyl analogues were found to exhibit better anthelmintic activity. The most active compound of the series, namely, methyl 5(6)-[(N-2-pyridylpiperazino)carbamoyl]benzimidazole-2-carbamate (90), has been screened against intestinal helminths in higher animals and as a micro- and macrofilaricidal agent. Compound 90 has been identified as a broad-spectrum anthelmintic agent. Compound 90 has been identified as a broad-spectrum anthelmintic in view of its efficacy against A. ceylanicum (hamsters and dogs), H. nana (rats), Nippostrongylus brasiliensis (rats), Syphacia obvelata (mice), A. tubaeformis (cat), Toxocara spp. (cat), and Litomosoides carinii (cotton rat).

Ancylostomiasis↗

Antibody affinity and immune complexes after immunization with tetanus toxoid in protein-energy malnutrition.

Protein-energy malnutrition reduced the affinity of antibody to tetanus toxoid, particularly after primary immunization. The effect on antibody affinity was more marked in patients with hypoproteinemia than in those with marasmus. Hemagglutinating antibody levels were comparable in undernourished and well-nourished groups. Circulating immune complexes were detected in eight of 21 children with protein-energy malnutrition and in one of the controls. Differences in antibody affinity in malnutrition may be an important determinant of altered host resistance and of complications of disease in nutritional deficiency.

Antibody Affinity↗

Photon absorptiometry for non-invasive measurement of bone mineral content.

Bone mineral content of the distal radius was determined in 106 patients by single photon absorptiometry using iodine-125 monochromatic source. The technique provided a reliable means to assess the degree of mineral loss in conditions such as osteoporosis, renal osteodystrophy in patients on chronic maintenance dialysis, subjects on long-term steroid therapy, and those with diabetes mellitus. It is more sensitive than conventional radiography and completely noninvasive compared to bone biopsy. It is suggested that photon absorptiometry is a simple, sensitive, and reliable technique for assessment and follow-up of the bone mineral content in a host of disorders associated with bone demineralization.

Adult↗

Autologous mixed lymphocyte reaction in man. IX. Autologous mixed lymphocyte reaction and lymphocyte subsets in aging humans.

Peripheral blood from 15 young (20-30 years) and 15 aging (65-80 years) subjects was analysed for the proliferative response of T cells upon stimulation with non-T cells in the autologous mixed culture reaction (AMLR) and allogeneic MLR, and for the proportion of monoclonal antibody-defined lymphocyte subsets and monocytes. No significant difference was observed in the AMLR or allogeneic MLR between T and non-T cells in aging and young subjects. However, when non-T cells were further fractionated into adherent monocytes and non-adherent B cells (B cells and null cells), the AMLR between macrophages and T cells was significantly (P less than 0.05) higher in young subjects than in simultaneously studied aging subjects. In contrast, the AMLR between T cells and B cells was significantly (P less than 0.05) higher in the aging subjects than in the young group. In the T-T AMLR (using phytohaemagglutinin-stimulated T cells as stimulators), aging subjects had a significantly (P less than 0.05) lower proliferative response than simultaneously studied young subjects. In vitro addition of purified interleukin 2 reconstituted the T-T AMLR to the base-line T-T AMLR in young humans. No significant difference was observed in the allogeneic MLR and lymphocyte subsets between the two groups. The significance of these observations is discussed.

Adult↗

Study of activated T cells in man. I. Discrepancy between Tac antigen and DR Antigen on T cells in patients with primary immunodeficiency.

DR and Tac antigens are present on T cells activated in vitro with mitogens and antigens but lacking on resting T cells. Freshly prepared peripheral blood T cells from patients with common variable immunodeficiency ( CVI ) and isolated IgA deficiency ( IAD ) were examined for the presence of DR and Tac antigens, using monoclonal antibodies and a fluorescence-activated cell sorter. Both Tac+ and DR+ T cells were significantly (P less than 0.05) increased in the patient group when compared with age- and sex-matched controls; however, a discrepancy was observed in the proportions of Tac+ T cells and DR+ T cells. This study demonstrates that, in certain patients with CVI and IAD , T cells are activated in vivo, and Tac and DR antigens could be expressed during different stages of T-cell activation.

Adolescent↗

Monoclonal antibody-defined B cell subsets in aging humans and Down's syndrome.

Peripheral blood from aging and young humans and patients with Down's syndrome, and from age- and sex-matched controls, was studied for the proportions of surface immunoglobulin (SIg+) bearing and monoclonal antibodies FMC1, and FMC7 defined B lymphocytes and B lymphocyte subsets using fluorescent-activated cell sorter. In aging humans, the proportion of SIg+ and FMC1+ (that detect all B lymphocytes) were comparable to simultaneously studied healthy young controls. However, FMC7+ (that detects a subset of B cells) B cells were significantly (p less than 0.05) increased when compared to young subjects. In aging subjects, the proportions of FMC7+ B cells were comparable to their FMC1+ B cells, whereas in young subjects FMC7+ B cells were a subset of FMC1+ B cells. In Down's syndrome, a phenomenon similar to aging humans was observed, that is the proportions of FMC7+ were increased when compared to age- and sex-matched controls and were comparable to their own FMC1+ B cells. This study demonstrates the abnormality of B lymphocytes in human aging and Down's syndrome. The significance of these findings is discussed.

Adult↗