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Biomedical subjects

S R Verma

Publications and source records attributed to S R Verma.

At least 19 recordsLinked to original sources
PubMed2003

Heavy metals contamination in surface and groundwater supply of an urban city.

There is a continuous increase in the demand of water supply in cities due to the industrialization and growing population. This extra supply is generally met by groundwaters or nearby available surface waters. It may lead into incomplete treatment and substandard supply of drinking water. To ensure that the intake water derived from surface and groundwater is clear, palatable, neither corrosive nor scale forming, free from undesirable taste, odor and acceptable from aesthetic and health point of view, the final water quality at Delhi have been evaluated. The final water supply of four treatment plants and 80 tubewells at Delhi were surveyed in 2000-2001 for cadmium, chromium, copper, iron, lead, manganese, nickel, selenium and zinc. The levels of manganese, copper, selenium and cadmium were found marginally above the Indian Standards (IS) specification regulated for drinking water. The data was used to assess the final water quality supplied at Delhi.

Cadmium↗
PubMed1988

High speed photographic analysis of aerosols produced by metered dose inhalers.

The design of pressurized metered dose inhalers (MDI) used to assess asthma is variable. We have examined the aerosol spray flumes generated by four commercially available MDI products using high speed video photography. For this purpose a moulded jacket was designed which could hold the inhaler in an immovable position during actuation. Fresh inhalers were fitted in the jacket after thorough shaking and three successive actuations 30 s apart were filmed with a high speed video camera (200 frames s-1). The aerosol, ejected at high velocity into calm room air, was seen to have a 'jet' phase followed by a 'cloud' phase as a result of particle dispersion. Filming was continued till the flume could no longer be visualized on the TV monitor. High speed photography was used to record flumes seen on the video monitor, to enable characterization of flume appearance, dimensions and mean velocity.

Aerosols↗
PubMed1986

Mercuric chloride-induced physiological dysfunction in Notopterus notopterus.

The freshwater fish Notopterus notopterus were exposed to various sublethal concentrations (0.088, 0.044, 0.029, 0.022, and 0.017) of mercuric chloride (HgCl2) mg/liter for 15, 30, 45, and 60 days, and their effects on glucose, lactate, cholesterol, plasma glutamic oxalacetic transaminase (PGOT) and plasma glutamic pyruvic transaminase (PGPT) of the blood were observed. Lactate increased significantly (P less than 0.05; P less than 0.01; P less than 0.001) and glucose. PGOT, and PGPT increased significantly (P less than 0.05; P less than 0.01). However, cholesterol decreased significantly (P less than 0.05; P less than 0.01; P less than 0.001) in the blood of N. notopterus.

Alanine Transaminase↗
PubMed1985

In vivo accumulation and effects of mercuric chloride on tissue phosphatases of Notopterus notopterus.

Sublethal concentrations of mercuric chloride inhibited the liver, kidney and gill enzymes, acid, alkaline, and glucose-6-phosphatase of the fish Notopterus notopterus, which had been exposed to the heavy metal for 30 days. Higher concentrations produced highly significant (p less than 0.001) inhibition, whereas concentrations that were 1/25th the lethal concentration caused significant (p less than 0.05)/insignificant inhibition. The quantity of mercuric chloride accumulated in tissues correlated with the degree of enzyme inhibition.

Animals↗
PubMed1984

Mercuric chloride stress on serum transaminase activity in Notopterus notopterus.

Mercuric intoxication at sublethal levels (1/5, 1/10, 1/15, 1/20 or 1/25 fractions of 96 h LC50) produced alterations in the activity of serum glutamic oxalacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) of Notopterus notopterus. The difference between control and treated fish was found to be significant at P less than 0.05, P less than 0.01 and P less than 0.001 levels. Maximum (81.75%) significant (P less than 0.001) effect was observed in SGOT: maximum (69.23%) significant (P less than 0.001) effect was observed in SGPT in fish exposed for 60 days.

Alanine Transaminase↗
PubMed1983

Pesticide-induced dysfunction in carbohydrate metabolism in three freshwater fishes.

In the present investigation, the effect of sublethal fractions (1/4th, 1/8th and 1/16th of 96-hr LC50) of thiotox and dichlorvos on blood glucose, lactate, and liver and muscle glycogen levels of Clarias batrachus, Saccobranchus fossilis, and Mystus vittatus, exposed for 30 days, have been studied. It was observed that blood glucose and lactate levels increased from 29.13 to 98.36% and from 10.88 to 36.36%, respectively. The liver and muscle glycogen decreased from 22.99 to 69.30% and from 5.19 to 32.19%, respectively. The reasons for this carbohydrate imbalance have also been suggested.

Animals↗
PubMed1983

In vivo effect of mercuric chloride on tissue ATPases of Notopterus notopterus.

Effect of sublethal concentrations, 0.088, 0.044, 0.029, 0.022 and 0.0176 mg HgCl2 per liter (1/5, 1/10, 1/15, 1/20, and 1/25 fractions of 96-h LC50) on Na+-K+, Mg2+, and total ATPase activities in brain, gills, kidney and liver of Notopterus notopterus have been studied after 30 days exposure. Na+-K+ ATPase were inhibited maximally and significantly in brain and minimally and insignificantly in liver. Mg2+ ATPase was inhibited maximally and significantly (P less than 0.01) in brain and minimally and insignificantly in kidney. The relative inhibition of total, Na+-K+ and Mg2+ ATPases for the tissues studied were brain greater than gill greater than kidney greater than liver. At the concentration (1/25 fraction) the enzyme activity returned to the normal range.

Adenosine Triphosphatases↗
PubMed1982

Toxicity of phenolic compounds in relation to the size of a freshwater fish, Notopterus notopterus (Pallas).

Fish, Notopterus notopterus, in four sizes (4.5 +/- 1.0, 9.0 +/- 1.0, 14.5 +/- 1.2, and 22.6 +/- 1.8 cm in length) were exposed to phenol (P), 2,4-dinitrophenol (DNP), and pentachlorophenol (PCP) separately, and also to their three combinations (PCP + DNP)/P (highly antagonistic), (DNP + P)/PCP (additive), and (P + DNP)/PCP (highly synergistic) to evaluate the effect of fish size on the toxicity of these chemicals separately and in combination. The results reveal that with increased fish size (from 4.5 + 1.0 to 14.5 + 12 cm in length) toxicity of phenolic compounds decreased. On the contrary, the larger size fish (22.6 +/- 1.8 cm in length) was comparatively more susceptible. This indicates that change in fish size does influence the toxicity of phenolic compounds.

Animals↗
PubMed1982

Effects of a few xenobiots on three phosphatases of Saccobranchus fossilis and the role of ascorbic acid in their toxicity.

The effects of 0.0021, 0.00126 and 0.00063 mg thiotox per liter and 5.18, 3.11 and 1.56 malathion per liter (1/3, 1/5, and 1/10 fractions of 96-h LC50) on acid, alkaline and glucose-6-phosphatases in liver, brain and gills of Saccobranchus fossilis were studied after 30 days exposure with or without ascorbic acid. These enzyme activities were altered by these pesticides, but lesser alterations were observed when ascorbic acid was given.

Acid Phosphatase↗
PubMed1982

Effects of sodium pentachlorophenate on enzymes of energy metabolism in tissues of Notopterus notopterus.

Effect of sublethal concentrations (0.0083, 0.0055, 0.0041, 0.0033 and 0.0028 mg/l) of sodium penta-chlorophenate (Na-PCP) on the enzymes SDH, PDH and LDH in brain, liver and gills of Notopterus notopterus after 15 ad 30 days exposure were studied. SDH and PDH were inhibited, and LDH were stimulated significantly at most concentrations. However, changes were maximum (-68.3%, -73.4% and +197.7% for SDH, PDH and LDH, respectively) in brain after 30 days, and minimum (-1.3% and +2.4% for SDH and LDH, respectively) in gills and (-3.4% for PDH) brain after 15 days. Inhibition of SDH and PDH, and the stimulation of LDH activity indicate the development of anaerobic conditions at the cellular level in pollutant-stressed fish.

Animals↗
PubMed1982

In vitro effect of mercury on tissue phosphatases of Notopterus notopterus and the role of EDTA and AA in their restoration.

In vitro effects of four sublethal concentrations (0.10, 0.40, 0.80 and 1.20 micrograms) of mercury (hg) on acid, alkaline and glucose-6-phosphatases of liver, kidney and gills of Notopterus notopterus were studied. The maximum (80.76%) significant (P less than 0.001) inhibition in acid phosphatase of gills and minimum (36.66%) significant (P less than 0.05%) inhibition in alkaline phosphatase of kidney was observed at 1.20 microgram and 0.10 microgram Hg concentrations, respectively. EDTA and ascorbic acid (AA) restored the phosphatase activity to the greatest extent when administered with the Hg.

Acid Phosphatase↗
PubMed1981

Synergism, antagonism, and additivity of phenol, pentachlorophenol, and dinitrophenol to a fish (Notopterus notopterus).

The toxicity of phenol (P), pentachlorophenol (PCP), and dinitrophenol (DNP) was determined separately and in different combinations with a test fish, Notopterus notopterus, using the procedure of Schubert et al. (1978) that provided a simple, sensitive, and quantitative index of synergism, antagonism and additivity. The combination (P + DNP)/PCP was found to be the most synergistic, while (PCP + DNP)/P was antagonistic in nature. The (DNP + P)/PCP combination was additive in its effect. The other combinations were also synergistic, but to a lesser extent than the (P + DNP)/PCP combination.

Animals↗