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Biomedical subjects

S Sehgal

Publications and source records attributed to S Sehgal.

At least 19 recordsLinked to original sources
PubMed1992

Effect of combined deficiency of fat and vitamin A on N-nitrosodiethylamine-induced lung carcinogenesis in mice.

The present investigation shows the effect of combined dietary deprivation of fat and vitamin A on N-nitrosodiethylamine (NDEA) induced lung carcinogenesis in male Swiss NMRI mice. Lung tumors were induced by three intragastric administrations of NDEA (80, 80, 40, mg/kg body wt.) in normal saline with a gap of 4 weeks between each administration. The tumor incidence and tumor burden in control animals were found to be 39.1 and 3.9%, respectively. Fat deficiency decreased the tumor incidence to 30.4% and tumor burden to 3.7%. On the other hand, vitamin A deficiency increased them to 95.6 and 6.8%, respectively. Fat deprivation in the diet of animals fed with vitamin A deficient diet decreased the tumor burden and tumor incidence to 59.0 and 4.0%, respectively which were still more than in the control animals. This study suggests a protective role for low intake of fat in vitamin A deficiency.

Animals↗
PubMed1992

Protein quality of developed home made weaning foods.

Home made weaning foods developed from locally available foods like bajra, barley, green gram (Vigna radiata L.), amaranth grain (Amaranthus sp.) and jaggery using household technologies like roasting and malting had a PER ranging from 2.04 to 2.13, BV 79.56 to 80.68, NPU 66.75 to 67.86, NPR 2.13 to 2.76 and PRE 34.18 to 44.18. The values were comparable to that of cerelac--a commercial weaning food.

Amaranthus↗
PubMed1992

Effect of domestic processing, cooking and germination on the trypsin inhibitor activity and tannin content of faba bean (Vicia faba).

The effects of domestic processing methods like soaking for 12 h, dehulling, ordinary cooking of whole as well as dehulled seeds at 15 lbs/inch2 pressure for 15 and 25 min, and germination for 24, 36 and 48 h were observed on trypsin inhibitor (TIA) and tannin content of two varieties of faba bean viz. VH-131 and WF. A non-significant reduction in TIA was observed on soaking and dehulling, while tannins showed a reduction of 42 and 51% on soaking in VH 131 and WF, respectively. Dehulled seeds showed a decline in tannin content by 70 to 73% in two varieties. There was a significant reduction in TIA (75-76 per cent) and tannin (76-81%) on cooking, while autoclaving for 25 min almost completely eliminated both of these stress factors. Germination of seeds for 48 h led to a reduction of 64-65% in TIA and 90-91% in tannins, which was more than germination for 24 and 36 h. Soaked seeds gave positive results of both these antinutrients.

Fabaceae↗
PubMed1992

Responses to hypoxia and hypercapnia in infants of substance-abusing mothers.

Because infants of substance-abusing mothers (ISAM) have an increased risk of sudden infant death syndrome and have abnormal sleeping ventilatory patterns, we studied the effects of mild hypoxia during quiet sleep on ventilatory pattern, heart rate, and arousal in 23 healthy ISAM (mean +/- SEM: 9.0 +/- 0.49 weeks of age) and 15 healthy, similarly aged, control infants. Hypercapnic challenges were performed in six ISAM and eight control subjects. Hypoxic arousal responses were elicited by rapidly decreasing inspired oxygen tension to 80 mm Hg for 3 minutes or until arousal occurred. Failure to arouse to hypoxia occurred in the majority of infants in both groups. All infants had a fall in end-tidal carbon dioxide tension during hypoxia, suggesting that each had a hypoxic ventilatory response. However, the fall in end-tidal carbon dioxide tension was significantly less in the ISAM (mean +/- SEM: -4.0 +/- 0.3 vs -8.0 +/- 1.0 mm Hg), suggesting blunted ventilatory responses to hypoxia. Periodic breathing occurred during 9.5% of hypoxic challenges in control infants compared with 37% in ISAM (p = 0.056). Heart rates were significantly higher in the ISAM before, during, and after hypoxic challenges. Hypercapnic challenges (inspired carbon dioxide tension of 60 mm Hg for a maximum of 3 minutes) resulted in arousal in all infants; however, ISAM required a significantly longer exposure to hypercapnia before arousal (mean +/- SEM; 116 +/- 7.8 vs 79 +/- 13.9 seconds; p < 0.02). We conclude that ISAM have an impaired repertoire of protective responses to hypoxia and hypercapnia during sleep, and that this may play a role in their increased risk for sudden infant death syndrome.

Arousal↗
PubMed1992

Humoral antibody response in Leishmania tropica infection.

A small epidemic of Leishmania tropica infection was detected in Rajasthan, India. Most cases were in the 21-25 years age group and were possibly related to outdoor activity. Nearly one third of the patients had more than five lesions, the maximum number of lesions being confined to the face, neck and extremities. As determined by ELISA, 90% cases had leishmania antibodies with an OD range of 0.8-1.1. The serum of 60% of patients was positive by CIEP against L. tropica promastigote soluble antigen. By immunofluorescence, 96% persons were positive when L. tropica promastigotes were used as the substrate. The prevalence of infection with L. tropica appears to be much higher than that reported earlier.

Adolescent↗
PubMed1992

Detection of leishmania antigen in kala azar patients using monoclonal antibodies.

Twenty-one monoclonal antibodies were produced against promastigote antigens of Leishmania donovani. Five monoclonal antibodies (Hyb.17, 6, 5, 4 and 2) identifying molecules associated with various L. donovani antigenic determinants ranging from 42-116 kDa were selected as 'capture antibodies' and compared with specific anti-leishmania antisera for detection of circulating leishmania antigens in kala azar patients' sera in a competitive-enzyme-linked immunosorbent assay system (ELISA). The anti-leishmania antisera could detect circulating antigen in 30% of kala azar cases while out of the five monoclonals, Hyb.17 could effectively detect circulating leishmania antigen in 85.4%. The efficacy of Hyb.6 was however low (31.7%). The antigens recognized by these monoclonal antibodies in the western blot assay could possibly represent the ones circulating in sera of patients suffering from kala azar. A cocktail of these monoclonal antibodies may be more useful than the conventional polyclonal antisera in detection of circulating antigen for clinical diagnosis of kala azar.

Animals↗
PubMed1992

Human sperm surface mapping with lectins.

Ten fluorescein isothiocyanate (FITC)-linked lectins [Bauhimia purpurea, Concanavalin A, Dolichos biflorus (DBA), Griffonia simplicifolia I, Griffonia simplicifolia II, Maclura pomifera, Arachis hypogea (PNA), Glycine max, Ulex europaeus (UEA) and Triticum vulgaris agglutinin] have been used to study their binding features on the human ejaculate spermatozoa. Qualitative changes in the labeling pattern have been observed in unfixed and acetone-treated spermatozoa. Furthermore, ultrastructural localization of some of the colloidal gold-linked lectins, namely PNA, UEA and DBA, has been attempted to delineate the binding domains of the specific sugars on the sperm surface. It needs to be emphasized that flow-cytometric methods employed in our study, which provide quantitative slant to qualitative data, should be utilized to evaluate the functional status of the spermatozoa.

Cell Membrane↗
PubMed1992

Comparative evaluation of HIV infected foreign students and Indian with AIDS in Chandigarh, India.

Out of a total of 1,600 foreign students who came to India between June 1989 and October 1990, 22 were seropositive for HIV-1. Ten showed antibodies to all the gene products. Antibodies to gp160 and p24 were present in all the seropositives while antibodies to p53, p15/17 were significantly higher in healthy seropositives than in patients with full blown AIDS. Absence of antibodies to p15/17 and p53 thus appeared to be a more sensitive criterion of end stage disease than absence of anti- p24 antibodies. When seropositive samples from African students were checked for HIV-2 antibodies by ELISA, 13/22 were found to be positive. Further, 2/10 Indians with full blown AIDS were also strongly positive for HIV-2. These data could be of relevance for formulating future strategies for population-based screening for HIV-2.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Secondary immune defects in non-Hodgkin's lymphoma.

Changes in the humoral, cellular and phagocytic components of the immune system were investigated in 44 biopsy proven, untreated patients of non-Hodgkin's lymphoma (NHL). There was significant decrease in the total lymphocyte number, their subsets (T and B) and the T helper (T mu) population. Impaired leukocyte migration inhibition response and DNA synthesis following stimulation by phytohaemagglutinin were noted. Significant reduction of serum IgA was found in patients of both diffuse and nodular NHL. Phagocytic activity and nitroblue tetrazolium (NBT) reduction were unaltered, but chemotaxis was significantly reduced and bactericidal activity showed variable results.

Antibody Formation↗
PubMed1991

Use of in vitro method to assess different brands of anti-leishmanial drugs.

Reports in the literature indicate the use of animal models for testing newer anti-leishmanial drugs in vivo. However, in certain established cell lines and macrophages in vitro models have the advantage over the in vivo system of simplicity and speed with which the results can be obtained. A simple in vitro system using peritoneal exudate macrophages of BALB/c mice infected with Leishmania donovani promastigotes has been tested for its use in determining the efficacy of several new drugs. Two well-established drugs, amphotericin B and sodium stibogluconate, as expected, could kill the intracellular parasites effectively. Two relatively new drugs not routinely used against leishmania, rifampicin and metronidazole at concentrations of 20 micrograms/ml and 10 micrograms/ml, respectively, were also able to kill the intracellular leishmania parasites effectively. Critical factors for drug testing in vitro have been elucidated: the most important being the temperature of incubation after infection.

Animals↗
PubMed1991

Development, acceptability and nutritional value of weaning mixtures.

Low cost weaning mixtures were prepared by mixing (i) malted pearl millet (Penicitum typhidium L), roasted amaranth (Amaranthus sp.); roasted green gram (Vigna radiata); jaggery and (ii) malted barley (Dehusked barley); roasted amaranth grain; roasted green gram; jaggery in proportion 60:20:40:45 wt/wt and were nutritionally evaluated. Both the blends had a nutrient composition within the range prescribed by the Indian Standard Institute (ISI) for processed weaning foods. The processing of grains resulted in lower levels of phytic acid, polyphenols and saponins and higher in vitro protein digestibility than those of the raw grains used for preparing mixtures. Both the mixtures were acceptable to trained panelists and children.

Amaranthus↗
PubMed1991

Correlation of HPV antigen and type of genital warts with atypia.

Five clinical types of genital warts were identified, studied histopathologically and stained for human papilloma virus (HPV) antigen. HPV antigen was found in all degrees of koilocytosis and it was present more often in the hyperplastic warts than in other types of genital warts. However, as reported earlier, the presence of HPV antigen did not decrease proportionately as the degree of atypia increased.

Antigens, Viral↗
PubMed1991

Immunohistochemical demonstration of mycobacterial antigens in intracranial tuberculoma.

Mycobacterial antigens have been demonstrated immunohistochemically in the paraffin sections of 10 intracranial tuberculous granulomas and the results were compared with the detection of acid fast bacilli by conventional Ziehl-Neelsen method. In none of the 10 specimens, acid fast bacilli were demonstrated while mycobacterial antigens were characterised as diffusely staining granular brownish-pink material within the cytoplasm of giant cells and macrophages. In 14 specimens of granulomatous lesions due to non-tuberculous aetiology, immunohistochemical stains were negative for mycobacterial antigen. Thus demonstration of mycobacterial antigen will be not only useful in establishing mycobacterial aetiology of a caseating intracranial granuloma but also can be used as an alternative method to the conventional Ziehl-Neelsen method.

Antigens, Bacterial↗
PubMed1991

An association of acute myeloid leukaemia and multiple myeloma: a case study.

A case of denovo presentation of acute myeloid leukaemia with multiple myeloma is reported in a 32 years old male. He presented with pancytopenia and aleukaemic leukaemia. Bone marrow examination revealed presence of acute myeloid leukaemia and sheets of plasma cells. Serum electrophoresis showed a M protein which was characterised to be Ig lambda with decrease in normal immunoglobulin levels.

Adult↗
PubMed1991

Circulating immune complexes in cerebrospinal fluid of patients with tuberculous meningitis.

Circulating immune complexes (ICs) were isolated from cerebrospinal fluids (CSFs) of patients with tuberculous meningitis (TBM), non-tuberculous neurological diseases by a polyethylene glycol (PEG) precipitation method. Mycobacterium tuberculosis antigen 5 was detected in CICs of 30% patients with TBM, by sandwich ELISA. CIC level decreases during antituberculosis chemotherapy and therefore its detection can provide a method to monitor the therapeutic schedule in patients with TBM.

Adolescent↗
PubMed1991

Histopathological studies in relation to protection induced by using MDP as an adjuvant in malaria.

Different immunomodulators were tried for their efficacy to protect against the lethal infection of Plasmodium berghei in mice. Since MDP was the most effective non-FCA adjuvant imparting a significant degree of protection, histopathological studies were undertaken in mice protected by using this adjuvant in comparison with mice suffering from acute malaria. The malarious mice revealed abnormalities of the liver, spleen and kidney, whereas these abnormalities were minimal in the MDP-immunized mice. The results are consistent with the degree of protection induced by MDP, and are significant with respect to the effectiveness of the non-FCA adjuvant in causing minimal histopathological abnormalities.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1991

Elevated plasma norepinephrine levels in infants of substance-abusing mothers.

Infants of substance-abusing mothers (ISAM) have significant growth and neurodevelopmental abnormalities. The origin of these abnormalities is unknown. We postulated that ISAM have increased sympathetic nervous system tone and altered catecholamine levels. Therefore, we measured plasma norepinephrine, epinephrine, and dopamine levels and the number and receptor affinity of beta-adrenoreceptor binding sites on lymphocytes and alpha-adrenoreceptor binding sites on thrombocytes in 22 otherwise healthy ISAM (age, 2.1 +/- 0.5 months; mean +/- SD) and 15 healthy controls (age, 2.5 +/- 0.8 months). Norepinephrine levels in venous blood were 1.8-fold higher in ISAM than in control infants (6.30 +/- 3.85 nmol/L vs 3.55 +/- 2.45 nmol/L). There were no differences in plasma epinephrine or dopamine levels. There were no differences in the number of binding sites or receptor affinity for beta- and alpha-adrenoreceptors. We conclude that ISAM have elevated circulating norepinephrine levels compared with controls. We speculate that this is associated with increased sympathetic nervous system tone in ISAM and that the absence of adrenoreceptor down-regulation may create catecholamine suprasensitivity.

Blood Platelets↗