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Biomedical subjects

S P Sharma

Publications and source records attributed to S P Sharma.

At least 73 records · Page 4Linked to original sources
PubMed1988

An antioxidant induced alterations in peroxidase activity in ageing Zaprionus paravittiger (Diptera).

Sodium hypophosphite (1 x 10(3) microM) supplementation in the diet of Zaprionus paravittiger resulted in adaptive responses in the quantitative as well as qualitative activity of peroxidase. The changes in peroxidase were in compliance with the earlier reported sodium hypophosphite (SHP)-induced prolonged life span of flies (Wadhwa, R., Arch. Gerontol. Geriatr., 6 (1987) 141-147) and support the concept that antioxidative enzymes may serve as important longevity determinants.

Animals↗
PubMed1988

The oxidant defence system in water-buffaloes (Bubalus bubalis) experimentally infected with Anaplasma marginale.

The glutathione (GSH) -oxidant defence system protects the erythrocytes and leucocytes from oxidative damage. Leucocyte -superoxide dismutase (SOD), GSH-peroxidase (GSH-px), GSH-reductase (GR), GSH-S-transferase (GSH-S-t) and arginase were examined in samples from buffaloes infected with Anaplasma marginale. All the enzymes, except arginase, were also studied in the red cell haemolysates from these animals. GSH-S-t, GSH- and glutathione-reductase (GR) levels in leucocytes decreased in infected animals suggesting a decline in the efficiency of the GSH-oxidant defence system. SOD levels increased but there was no change in leucocyte-arginase activity due to infection. Infection caused no significant changes in red cell SOD, GSH-px, GR and GSH. However, GSH-S-t significantly decreased (P less than 0.05).

Anaplasmosis↗
PubMed1987

Studies on catalase in ageing Zaprionus paravittiger (Diptera) with special reference to an antioxidant feeding.

Zaprionus paravittiger fed with an antioxidant (sodium hypophosphite, 1 X 10(3) microM) supplemented diet exhibited adaptive compensatory responses in catalase activity (quantitative as well as qualitative). The longevity and catalase activity were found to be positively linked. The study denotes that free radical formation and antioxygenic defenses are closely associated and are the possible determinants of life span and ageing.

Aging↗
PubMed1986

Observations on histamine, serotonin, cortisol and cortisol binding globulins in bovine anaplasmosis.

Changes in histamine, serotonin, cortisol and cortisol binding globulin (CBG) levels were observed in Anaplasma marginale-infected bovine calves. In addition, packed cell volume (PCV), platelet number and percentage parasitaemia were also recorded. The whole blood histamine and serotonin values rose significantly (P less than 0.01 and P less than 0.025, respectively) during the acute stage of Anaplasma infection. Higher serum cortisol and CBG levels (P less than 0.05) were observed in acute and carrier infections, respectively. A sharp drop in thrombocyte count (59%) and PCV (33%) was also noticed in clinical anaplasmosis. The results suggest that the higher levels of biogenic amines which are known to produce increased vasodilation, capillary permeability and tissue anoxia and hypercortisolaemia to protect animals from stress and cell damage may play a similar role in the pathogenesis of acute anaplasmosis.

Anaplasmosis↗
PubMed1986

Efficacy of parvaquone and long-acting oxytetracycline in Theileria annulata infection.

Therapeutic and prophylactic efficacies of parvaquone and long-acting oxytetracycline were tested against Theileria annulata infection, induced by injecting a suspension of infected ground tick tissues (GUTS) into groups of 4 or 5 calves. This infection killed two of four control calves, while all the animals given a single intramuscular dose of 20 mg kg-1 parvaquone or long-acting oxytetracycline on the day of infection underwent mild reactions and recovered. Two separate doses of parvaquone of 10 mg kg-1 administered on the first and second days of fever protected four out of five calves. All the recovered animals from both treated and control groups resisted a homologous challenge with GUTS on Day 45 post-infection which killed three out of four susceptible unimmunized control calves.

Animals↗
PubMed1986

Changes in total and mitochondrial nucleic acid content in aging Caryedon serratus Oliver (Coleoptera).

Aging in the beetle Caryedon serratus was accompanied by a decline in total DNA content (9.28% in males and 9.79% in females). Mitochondrial DNA remained constant until the 11th day of age and then decreased gradually with advancing age in both sexes. RNA content and the RNA/DNA ratio showed similar changes in whole body as well as mitochondrial fractions. The two parameters decreased continuously and significantly (p less than 0.001) in males whereas in females an initial rise during the reproductive period was followed by decline until death. The observations suggest that there is a loss of mitochondria in the senescent period and a decline in the total nucleic acid content and protein synthetic capacity of C. serratus.

Aging↗
PubMed1986

Life span studies in Zaprionus paravittiger with sodium hypophosphite feeding.

The median and maximum life spans of Zaprionus paravittiger at 26 +/- 2 degrees C were 35.45 +/- 0.39 and 70.0 +/- 1.00 days, respectively, in males and 39.93 +/- 0.40 and 77.67 +/- 0.58 days in females. Feeding of an antioxidant-sodium hypophoshite (SHP), 1, 10 1 X 10(2) and 1 X 10(3) microM-resulted in increased survival of both sexes. Further increase in SHP concentration accelerated the mortality rate. Secondly, the lipid peroxide level as measured by malondialdehyde content showed an age-related increase in normal as well as SHP-fed cohorts. However, the rate of increase was much slower in the latter. It is suggested that SHP, by virtue of its free-radical scavenging property, prolongs the life span of Z. paravittiger.

Aging↗
PubMed1985

Age-associated changes in nucleic acid content in Zaprionus paravittiger.

The mean life span of male and female Zaprionus paravittiger reared on corn meal agar medium at 26 +/- 2 degrees C was found to be 35 and 40 days, respectively. The DNA content showed a perpetual decline in both sexes. The RNA content also showed a continuous decline in males while in females a significant leap is found during the first 17 days followed by a steady decline until the 41st day. The study supports the concept that protein synthesis (RNA-DNA) and thus the biological expression during different phases of life, are controlled at the DNA-RNA level.

Aging↗
PubMed1985

Observations on erythrocytic acetylcholinesterase activity in experimentally induced anaplasmosis in calves.

Erythrocytic acetylcholinesterase (AChE) activity was assessed in splenectomized bovine calves inoculated with Anaplasma marginale. Other parameters, i.e., haematological values (haemoglobin, packed-cell volume, and total erythrocytic count), percentage parasitaemia and the ensuing host reactions during Anaplasma infection were also studied in relation to AChE activity. There was significant inhibition of red blood cell-AChE activity commencing soon after inoculation of infected blood; this preceded a substantial decrease in haematological values along with high parasitaemia. The changes in AChE activity may possibly be associated with increased cell membrane permeability, thus triggering the entry of A. marginale organisms into red blood cells.

Acetylcholinesterase↗
PubMed1985

Chemoprophylaxis of Anaplasma ovis infection in sheep with a long-acting oxytetracycline.

The chemoprophylactic efficacy of long-acting oxytetracycline was determined in 13 susceptible ewes infected with Anaplasma ovis. The drug was administered intramuscularly at a dose rate of 20 mg kg-1 body weight during the prepatent period. When the ewes were exposed to an equivalent homologous challenge on Day 45 post-infection, each showed a mild or inapparent reaction. The host reactions, i.e., body temperature, parasitaemia, packed-cell volume (PCV), haemoglobin, humoral and cell mediated immunity (CMI) were also studied. The results indicate that the use of oxytetracycline during the incubation period would minimise clinical signs of an Anaplasma infection; this may be due to an increasing CMI response.

Anaplasma↗