PubMed Health⌕ Search

Biomedical subjects

G Prasad

Publications and source records attributed to G Prasad.

At least 19 recordsLinked to original sources
PubMed1992

Bluetongue virus infection in India: a review.

The history and epizootiology of bluetongue (BT) in India are reviewed. BT has become endemic in India. The first outbreak of BT in sheep and goats in the country was recorded in 1964 in Maharashtra State. Since then, several outbreaks of BT have been reported in sheep. Exotic sheep are more susceptible than indigenous and cross-bred sheep. A serological survey has indicated the presence of bluetongue virus (BTV) antibodies in cattle and buffalo in several states in India. However, clinical BT has not been observed in cattle or buffalo to date. Of the 24 known serotypes of BTV, 18 have been reported in India. Although BTV has been isolated from Culicoides midges, the particular species responsible for transmission has not yet been identified.

Animals↗
PubMed1992

Characterization of a continuous lymphocyte cell line derived from BALB/c mice inoculated with a recombinant Moloney murine leukemia virus-TB.

Neonatal BALB/c mice were inoculated (ip) with a recombinant Moloney murine leukemia virus-TB. Majority of the inoculated mice developed lymphoma within 5-7 months post infection. The cells from splenic lymphomas were cultured and 3 continuous cell lines (GP1, GP2 and GP3) developed. GP1 was single cell cloned and characterized. Based on Thy 1.2 (98.4%) phenotypic marker, the cell line was categorized as T cell line. The percent positivity for different cell surface markers on analysis with FACS was 98.4, 4.8, 5.5, 2.2, 1.8, 1.2 and 9.5 for Thy 1.2, mu, L3T4, Lyt2, Ia, IL2R and PNA receptor, respectively. A total of 16.5% GP1 cells was also positive for Moloney murine leukemia virus envelope protein (gp 70). Incomplete retrovirus like particles were demonstrated in the cytoplasm of GP1 cells by electron microscopy. The cell line on inoculation(ip) in neonatal BALB/c mice produced lymphomic lesions in almost all the vital organs of the mice.

Animals↗
PubMed1992

Pathogenesis of age dependent paralysis by a temperature sensitive mutant (tsl) of Moloney murine leukemia virus-TB.

The tsl mutant of Moloney murine leukemia virus-TB produces neurological disease leading to fatal hind limb paralysis when inoculated in newborn BALB/c mice. The present study was under taken to assess the role of T and B lymphocytes in age dependent resistance to tsl induced paralysis in BALB/c mice. The adoptive transfer of non-immune splenic unseparated lymphoid cells, T cells and B cells and tsl immune B cells and T cells to newborn BALB/c mice infected with tsl did not prevent the development of paralysis. However, adoptive transfer of immune splenic unseparated lymphoid cells and immune T cells delayed the onset of paralysis by 5 to 10 days as compared to the mice which did not receive the immune lymphocytes. Athymic BALB/c nude mice inoculated with tsl at days 1 and 10 after birth failed to develop the paralytic disease. Transfer of tsl neutralising antibody also delayed the onset of paralysis. Mice (10 days old) treated with cyclophosphamide, cyclosporine A, cortisone acetate and anti-T cell serum when inoculated with tsl also did not develop neurological disease. The results suggest that age related resistance to neurological disease may not be associated with B cell mediated immunity.

Age Factors↗
PubMed1992

Anencephaly.

Explore the source record for details and available documents.

Adolescent↗
PubMed1991

Dot immunobinding assay for the detection of bluetongue virus antibodies in sheep experimentally inoculated with bluetongue virus type 1.

Dot immunobinding assay (DIA) was evaluated for the detection of bluetongue virus (BTV) antibodies in sheep experimentally inoculated with BTV 1. Serum samples collected on 14, 21, 28, 43 and 60 day post infection (dpi) were positive for precipitating antibodies by the agar gel precipitation test (AGPT) while antibodies could be detected as early as 7 dpi by DIA and ELISA. Virus neutralizing antibodies were detected first at 14 dpi. The sensitivity of the four tests was compared on the same serum samples collected at different intervals. The results indicated that DIA was more sensitive than AGPT and the serum neutralization test and as sensitive as ELISA. Thus due to sensitivity simplicity and economy, DIA could replace AGPT for diagnosis and serological survey for BTV infection in animals.

Animals↗
PubMed1990

Characterisation of cell-wall-derived polypeptide antigens from different species of Mycobacterium.

Cell walls from different species of Mycobacterium were purified on a sucrose step gradient. The components derived from these preparations were characterised by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, followed by staining or by Western blotting. Surface-exposed polypeptide molecules were also identified by biotinylation. Many protein and glycoprotein molecules were identified in the cell walls. Some of these molecules were immunogenic in man and experimental animals and showed wide variability from species to species. The data suggest that these molecules could be of significance in the diagnosis and pathophysiology of mycobacterial diseases.

Antigens, Bacterial↗
PubMed1989

Structure-activity relationships for the inhibition of DNA polymerase alpha by aphidicolin derivatives.

Aphidicolin and 17 derivatives that have been structurally modified in the A- and D-rings were assessed for their ability to inhibit DNA polymerase alpha. No derivative surpassed the activity of aphidicolin; derivatives with structural alterations in the A-ring exhibited significantly greater loss of activity relative to derivatives with structural alterations in the D-ring. The conclusions of these studies indicate a critical role for the C-18 function in the interaction of aphidicolin with polymerase alpha. Molecular modelling studies could not identify structural features of the aphidicolin-dCTP "overlap" that is unique to dCTP, relative to the remaining dNTPs, and that is consistent with the extant structure-activity data.

Aphidicolin↗
PubMed1989

The role of the thymus in the pathogenesis of hind-limb paralysis induced by ts1, a mutant of Moloney murine leukemia virus-TB.

Newborn homozygous BALB/c nude (nu/nu) mice, their heterozygous (+/nu) littermates, and normal BALB/c (+/+) mice were infected with ts1, a paralytogenic mutant of Moloney murine leukemia virus-TB (MoMuLV-TB). Our results indicate that while infection of +/nu and +/+ mice with ts1 results in severe pathological changes in the central nervous system (CNS) and paralysis, infection of nu/nu mice results in only mild to moderate pathology within the CNS and no paralysis. On the other hand, 50% of nude mice reconstituted with T cells when infected with ts1 developed paralysis and showed more pronounced degeneration of nervous tissue than nude mice infected with ts1 alone. These observations strongly suggest that the thymus, the functional T lymphocytes, or both play an important role in the ts1-induced neurologic disorders in infected mice.

Animals↗
PubMed1989

ts1, a mutant of Moloney murine leukemia virus-TB, causes both immunodeficiency and neurologic disorders in BALB/c mice.

BALB/c mice infected with ts1, a mutant of Moloney murine leukemia virus-TB, develop generalized body wasting, profound neurologic disorders, severe thymic atrophy and lymphopenia due to destruction of T lymphocytes and drastic immunodeficiency. ts1 was found not only able to infect T lymphocytes but also to impair their function. In addition, ts1 also infects and induces syncyntia formation in macrophages. The genetic determinant(s) responsible for ts1's ability to induce immunodeficiency has been localized to the env gene.

Animals↗
PubMed1985

Histochemical alterations in the duodenum of goats experimentally infected with Paramphistomum cervi.

Certain histochemical alterations in the different tunics of duodenum in kids were studied 20, 40, 60 and 80 days post-infection (DPI) with Paramphistomum cervi and the results compared with those of uninfected kids. There was a general reduction of polysaccharide complex substances and glycogen at 20 DPI. A marked decrease in polysaccharide complex substances and glycogen at 20 DPI. A marked decrease in polysaccharide complex substances and glycogen was especially discernible in the Brunner's gland and muscularis mucosa 20 DPI. Thereafter, these substances gradually increased and at 80 DPI this decrease was fully replenished. A slight reduction in mucin and protein content of the infected duodenal goblet cells was noticed at 20 DPI. It is suggested that juvenile P. cervi utilize host-tissue polysaccharide complex substances and glycogen for their growth and development during duodenal migration.

Animals↗
PubMed1976

Relapse in pulmonary tuberculosis.

Five hundred forty-three patients with bacteriologically confirmed pulmonary tuberculosis who successfully completed treatment were followed for 5 years to determine relapse rates and to see whether any factors could be said to predispose to relapse. Practically the entire treatment of these patients had been carried out in their homes. The cumulative relapse rate during a 5-year period was 11.60 per cent. Relapse rates were low during the first 2 years of follow-up. Of the various factors considered in the analysis, age, sex, initial extent of disease or cavitation, and presence of initial or emergent drug-resistant bacilli did not influence the relapse rate. Patients who achieved complete radiographic clearing at the time treatment was stopped and those who were regular in treatment had comparatively low relapse rates. Cured patients included in the study were asked to report at least once annually for a checkup, and immediately if they developed any symptoms suggestive of relapse. Only one fourth of the cases of relapse were detected during routine annual checkup; in the remaining cases, the patients attended ahead of the next due visit because of symptoms. This casts doubt on the utility of keeping cured patients under prolonged routine surveillance.

Adult↗