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Biomedical subjects

S Sehgal

Publications and source records attributed to S Sehgal.

At least 73 records · Page 4Linked to original sources
PubMed1996

Serotype analysis of Indian patients with HIV infection.

HIV infection has established itself in India. Besides Bombay, Madras and Manipur it has assumed epidemic proportions in Punjab, where 24% of seropositives acquired infection through blood products. Preliminary observations on genetic analysis in 13 isolates revealed that the principal neutralizing determinant (PND) of the V3 loop was closely related to the South African isolate. Since serotyping can give reliable information about genotypic prevalence in the population, serotyping in the present study used 5 synthetic peptides (NOF, EL1, MN, IIIB, IND) of African, North American, European and Indian origin. The Indian consensus was derived from genotype analysis of 13 cases. Results of serotype analysis indicated that 82% of patients harboured a strain related to the South African type of HIV-1. These observations have a sinister significance for designing vaccine strategies for this region.

Amino Acid Sequence↗
PubMed1996

Effect of immunization with human SP-10 in male rodents.

PROBLEM: Over the years immunocontraception has emerged as a promising modality. Theoretically it is possible to intercept fertility using a panel of antigens expressed along the entire pituitary, hypothalamus and gonadal axis. One such sperm antigen designated as SP-10 is in advanced stages of development. Its gene has been cloned by Wright et al. (Biol Reprod 1990; 42:693-701). It is envisaged that immunization with SP-10 would induce antisperm antibodies in females and hence interrupt fertility. However, the in vivo effect of SP-10 immunization has been assessed in male rodents with particular reference to spermatogenesis and effect of such immunization in various tissues. The SP-10 antigen was a generous gift from Dr. John Herr. METHODS: A group of male Wistar rats and BALB/c mice were immunized with a total dose of 175 micrograms of SP-10 glutathione transferase fusion protein. Anti-SP-10 antibodies generated were detected by ELISA, immunofluorescence, flow cytometry and western blot assay. Histopathology of all the organs was conducted with particular reference to assess their effect on sperm maturation in testicular sections. RESULTS: All the animals immunized with SP-10 depicted a significant antibody response. DNA analysis by flow cytometry did not reveal any arrest of spermatogenesis, which was confirmed by histological studies. CONCLUSIONS: It is concluded that conventional immunization generating significant antibody titers does not induce arrest of spermatogenesis in male rodents.

Acrosome↗
PubMed1995

Effect of home processing on total and extractable calcium and zinc content of spinach (Spinach oleracia) and amaranth (Amaranthus tricolor) leaves.

Spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves were stored in polyethylene bags and without packing for 24 and 48 hours in a refrigerator at 5 and 30 degrees C in polyethylene bags. The fresh leaves were also dried (oven and sun); blanched (5, 10 and 15 min) and cooked in an open pan and a pressure cooker. The processed leaves were analysed for total and extractable calcium and zinc content. The Ca and Zn content of these leaves varied from 1320 to 2120 and 11.70 to 12.60 mg/100 g DM and the percentage HCl-extractability was 77.82 to 81.92 and 85.16 to 86.15, respectively. No significant effects of drying and storage were observed on total Ca and Zn content and HCl-extractability while blanching and cooking resulted in significant improvement of HCl-extractability of these two minerals. Thus, cooking and blanching are good ways to improve the HCl-extractability of Ca and Zn.

Amaranthus↗
PubMed1995

Effect of home processing on ascorbic acid and beta-carotene content of spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves.

The present investigation was conducted to study the concentration of ascorbic acid and beta-carotene in spinach and amaranth leaves as affected by various domestic processing and cooking methods which included storage of leaves in polythene bags or without packing for 24 and 48 hours in refrigerator at 5 degrees C; at 30 degrees C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min); open pan and pressure cooking. Ascorbic acid content of fresh leaves was 624.1 to 629.0 mg and beta-carotene content was 35.3 to 53.1 mg/100 g dry weight. The percent loss of ascorbic acid ranged from 1.1 to 6.3 and 55.3 to 65.9 while lower losses (0.0 to 1.3 and 1.5 to 2.1) of beta-carotene were observed in leaves stored in refrigerator and at 30 degrees C, respectively. A markedly greater reduction in ascorbic acid and beta-carotene was observed in dried, blanched and cooked leaves. The study recommended the storage of leaves in refrigerator, drying in oven, blanching for shorter time and cooking in pressure cooker for better retention of these two vitamins.

Amaranthus↗
PubMed1995

Improvement in HC1-extractability of minerals in home made weaning foods.

Three weaning foods were formulated from locally available cereals and pulses such as rice (Oryza sativa), kangini (Setaria italica), sanwak (Echinochloa frumentacea), green gram (Vigna radiata) and jaggery. Cereals and pulses were mixed in the proportion of 7:3. Nutrient composition of developed weaning foods was within range prescribed by Indian Standard Institute and was found to be acceptable. Roasting was the processing technique employed in developing weaning foods which resulted in significant increase in HC1-extractable minerals, an index of their bioavailability to humans. The higher HC1-extractability of the minerals may be ascribed to the decreased phytic acid in the processed home made weaning foods.

Biological Availability↗
PubMed1995

Lack of serological specificity of recombinant heat shock protein of Leishmania donovani.

In order to identify a specific recombinant antigen of Leishmania donovani with potential use for diagnosis, a cDNA library was constructed in lambda ZAP II expression vector. On screening the cDNA library using pooled sera from Indian patients with kala azar, 20 antibody reactive clones were identified. These were subcloned into pBluescript phagemid by an in vivo excision procedure. The molecular weights of the expressed recombinant proteins varied from 15 to 70 kDa and the cDNA insert sizes varied from 0.5 kb to the largest size of approximately 2.0 kb which was designated as the E2b clone. The nucleotide sequencing revealed that 50% of the clones had sequence homology to the heat shock protein gene of L. donovani. The serological studies conducted with the kala azar positive sera and sera from healthy laboratory workers using the recombinant protein from the E2b clone and having sequence homology to Ldhsp 70, indicated that although all the kala azar sera was positive, 12 of 20 healthy individuals also showed antibodies against the recombinant hsp70, indicating that this antigen is not suitable for serological diagnosis of kala azar.

Animals↗
PubMed1995

A genetic analysis of HIV-1 from Punjab, India reveals the presence of multiple variants.

OBJECTIVE: To determine the extent of HIV-1 genetic variation in Indian patients. DESIGN: To avoid any bias in selecting viral variants, HIV-1 DNA was amplified directly from the peripheral blood mononuclear cells of patients and sequenced. Genetic similarity between Indian sequences and other geographic isolates was analysed by phylogenetic analysis algorithms. METHODS: A fragment encompassing the C2/V3-V5 regions of HIV-1 gp120 was amplified from the lymphocyte DNA of 12 Indian patients. Multiple clones from each patient were sequenced. Nucleotide sequences encompassing about 650 base pairs were aligned for the Indian and other geographically distinct isolates. Inter-isolate relationships were analysed by means of distance, parsimony and neighbour-joining algorithms. RESULTS: Nucleotide sequence comparisons showed low interpatient variation. Amino-acid comparisons revealed a high degree of homology between Indian sequences in this study and those studied earlier. On distance and parsimony trees, most of the Indian sequences clustered together as subtype C. However, sequences from three patients also showed significant homologies and phylogenetic clustering outside of subtype C. CONCLUSIONS: The predominant strain of HIV-1 in India belongs to subtype C and little interpatient nucleotide sequence divergence in the majority of cases suggests recent spread of HIV-1 in this region. This study also presents the first evidence for non-C subtypes in the Indian population with two epidemiologically linked samples remaining unclassified for any existing env subtype. The presence of variant subtypes in Indian patients sheds light on the transmission routes of HIV-1 to India and emphasizes the need to include these sequences in vaccine development strategies.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Immunofluorescence study of pemphigus from north India.

Both serum studies by indirect immunofluorescence (IIF) tests and skin biopsy examination by direct immunofluorescence (DIF) were performed on 22 cases of pemphigus with clinically active lesions. Twenty cases had pemphigus vulgaris and two, pemphigus foliaceus. The majority of cases (70%) were between 21 and 60 years old; the mean age was 39.5 +/- 12.7 years. There was no sex predilection. DIF showed the positive fluorescence of intercellular cement substance (ICS) of the epidermis in all 22 cases (100%). IgG was positive in 77.2%, followed sequentially by C3C (50%), IgA (45.45%), and IgM (36.36%). Six cases (27.27%) also showed granular immunoglobulin and/or complement deposits at the dermoepidermal junction. IIF detected serum antiepithelial antibodies in 18 cases (81.81%) using human esophagus as substrate. Most of these cases (88.88%) showed IgG type of antibodies; the other 11.11% exhibited IgA and IgM in low concentrations. 1+ titer positivity was observed in 15 cases. This study demonstrates the value of DIF for a definitive diagnosis of pemphigus. However, it is also important to appreciate that immunofluorescence is not a substitute for histopathology, but rather complementary to it.

Adult↗
PubMed1995

Antismooth muscle and antiparietal cell antibodies in Indians with alopecia areata.

BACKGROUND: Alopecia areata is suspected to be an autoimmune disease. We studied 104 consecutive patients with alopecia areata for the presence of autoantibodies and associated autoimmune diseases. METHODS: A detailed history and examination was carried out in all patients to look for associated atopy, diabetes mellitus, hypertension, rheumatoid arthritis, vitiligo, lupus erythematosus, and thyroid disorders, etc. in the patients or their family members. Venous blood for estimation of fasting and postprandial blood glucose was collected in 30 patients, especially in those with family history of diabetes mellitus. Antimitochondrial (AMA), antismooth muscle (SMA), antinuclear antibodies (ANA), antiparietal cell antibody (PCA), and antibody against thyroid microsome (TMA) were detected employing indirect immunofluorescence on a composite section of rat liver, stomach, kidney, and human thyroid. Skin biopsy was processed for direct immunofluorescence by a conventional technique. RESULTS: Disseminated discoid lupus erythematosus, lichen planus, urticaria, psoriasis, and seronegative spondylarthritis were associated with alopecia areata in one case each. Antismooth-muscle-antibodies and PCA were found in 36 (34.6%) and 44 (42.3%) patients respectively, followed by TMA in 8 (7.7%), AMA in 6 (5.7%), antithyroglobulin antibodies in 3 (2.8%), and ANA in 2 (1.9%) patients. The incidence of SMA was higher in men with alopecia areata (P < 0.001). Direct immunofluorescence carried out in 24 patients did not reveal significant findings, except for occasional immunoglobulin deposits around hair follicles and blood vessels. CONCLUSION: Alopecia areata in India is associated more often with antismooth muscle and antiparietal cell antibodies.

Adult↗
PubMed1995

Comparative evaluation of anti-heat shock protein antibodies in SLE and healthy controls.

Presence of anti-heat shock protein (anti-hsp) antibodies have earlier been demonstrated in children as well as adult patients with systemic lupus erythmatosus (SLE). Since hsp share homology across several species, it is presumed that anti-E. coli antibodies could in fact be autoantibodies. Surface expression of hsps has also been shown to play a role in the generation of antibodies. In the present study antibodies to a recombinant hsp70 of Leishmania dnonvani origin have been investigated in patients with SLE and data compared with the incidence in control sera. One clone from the cDNA library of Leishmania donovani confirmed previously to be expressing hsp70, cloned in pBluescript and antibodies to the expressed protein were checked by ELISA and western blot assays. The results indicate the presence of anti-hsp70 antibodies in 22/26 (85%) SLE patients and 12/20 (60%) control sera. Our observations reconfirm the presence of antibodies to hsp in normal controls and therefore they may not bear any direct relation to the pathogenesis of SLE.

Adult↗
PubMed1995

Post-kala-azar dermal leishmaniasis mimicking leprosy: experience with 4 patients, with some unusual features in 1.

We report on 4 cases of post-kala-azar dermal leishmaniasis (PKDL). History of kala-azar was available in all 4 patients. Slit-skin smears (SSS) for leishmania donovani (LD) bodies were negative in all 4. In 3 patients hypopigmented lesions were present over the face. Papules and nodules over his lips, tongue, scrotum and dactylitis were some unusual features observed in 1 patient. Histopathological examination showed LD bodies in 2 patients; histopathology was nonspecific in the other 2. All the patients were treated with sodium stibogluconate, 20 mg/kg/day. Infiltrated papules and nodules had subsided by 3 months, while hypopigmented macules took longer to improve. In 3 patients there had previously been a misdiagnosis as leprosy sufferers and they had been treated with antileprosy drugs. Clinical and histopathological differences between PKDL and leprosy are discussed.

Adult↗
PubMed1995

Ten year longitudinal study of efficacy and safety of purified chick embryo cell vaccine for pre- and post-exposure prophylaxis of rabies in Indian population.

One thousand three hundred and seventy-five (1375) persons, who were vaccinated against Rabies with Purified Chick Embryo Cell (PCEC) vaccine from 1984 to 1993, were included in this ten-year longitudinal study, conducted to observe the consistency, immunogenicity, inocuity, safety and efficacy of PCEC vaccine under controlled trial and field conditions. The study period was divided into three phases. Phases I and II covered the premarketing controlled trial and Phase III the post-marketing serosurveillance study of the vaccine. During Phase I, fifteen healthy volunteers were given a pre-exposure regime of vaccine on Day 0, 7 and 21, and the rest 15, simulated post-exposure regime on Day 0, 3, 7, 14, 30 and 90. All the subjects had satisfactory antirabies antibody response with mean titres, of 7.08 and 5.72 I.U./ml respectively, and minimal side reactions. In the Phase II, from 1984-85, 56 persons with proven rabid animal bites were given post-exposure vaccination and all had satisfactory antibody titres with mean titre of 4.45 I.U./ml after 6th dose of vaccine and with minimal side reactions. 19 to 36 months follow up after vaccination revealed no vaccine failures. In the Phase III post-marketing field study conducted from 1985 to 1993, 1289 persons reported to our Centre for consulation and antirabies antibody titre estimation following PCEC vaccination. One thousand two hundred and fifty-two (1252) persons took post-exposure vaccination following bites by rabid animals, contact with an hydrophobia patient and 37 high risk personnel took pre-exposure vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

HIV epidemic in Punjab.

A total of 58890 subjects were screened for HIV infection between June 1987 to December 1992. Out of these, 42776 were blood donors and only 9 were positive for HIV by ELISA; 2749 were foreign students and 35 were confirmed positive both by ELISA and Western blot. Out of the remaining high risk subjects, 141 of 13365 were confirmed to be HIV positive with a cumulative positivity rate of 10.5 per thousand. Out of the 141 confirmed sero positives, 47 had full blown disease and 25 were dead by the time of compilation of data. Thirty seven i.e., 24.6 per cent had acquired infection through unscreened blood/products/haemodialysis. Thus Punjab has shown a steady rise of HIV infection over the last five years and the incidence of blood borne infection is very high.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Primary IgA nephropathy: a preliminary report.

A total of 106 renal biopsies were examined. Each biopsy was processed for routine paraffin sectioning and frozen sectioning. Direct immunofluorescence was done by the conventional method. The immunofluorescence patterns were correlated with histopathological changes and clinical presentation. Fourteen biopsies revealed weak to strong IgA staining and out of these, 11 seemed to fulfil the criteria of primary IgA nephropathy. These cases were diagnosed in a brief period of eleven months and there had not been any earlier published series from India.

Adolescent↗