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Biomedical subjects

S H Zaidi

Publications and source records attributed to S H Zaidi.

At least 73 records · Page 4Linked to original sources
PubMed1976

Frequency of malignant tumours in Jinnah Postgraduate Medical Centre, Karachi.

The frequency of malignant tumours seen in the Departments of Pathology and Radiotherapy of Jinnah Postgraduate Medical Centre, Karachi, from 1960 to 1972 during which 4753 and 9258 male and 4080 and 6693 female cases were seen in the respective departments has been reported. A marked similarity in the frequency pattern of the malignant tumours was observed. The most common fumours were those of Oral Cavity, Pharynx, Larynx, Oesophagus, Bronchus and Skin in males and Oral Cavity, Breast, Cervix and Oesophagus in famales.

Female↗
PubMed1975

Effect of intratracheal injection of mica dust on the lymph nodes of guinea pigs.

Histopathological changes in the tracheo-bronchial lymph nodes were studied up to 365 days in guinea pigs following intratracheal injection of a suspension of mica dust. In general, the cytotoxic effect provoked by dust was not pronounced as the majority of the swollen dust-laden macrophages retained their normal structure at the termination of the experiment and fibrotic lesions were limited to the formation of thick reticulin fibers. The poor fibrogenic response of mica dust has been attributed to its low cytotoxicity.

Aluminum Silicates↗
PubMed1975

Effect of quartz dust on the lungs of mice.

Intratracheal inoculations of quartz dust (250 mg/kg body weight) of a particle size less than 5 mum were given in mice and pulmonary tissue reactions studied over a period of 210 days. Acute inflammatory reaction in the lung parenchyma was observed at early periods and later the aggregates of dust laden macrophages encountered around bronchi and blood vessels. Towards the termination of the experiment at 210 days the fibrotic reaction comprised chiefly of thick compactly arranged reticulin fibers with few collagen fibers which remained restricted to the peribronchial and perivascular areas. There was no silicotic nodule formation in the parenchyma of the lung. The atypical pulmonary tissue response to quartz dust in mice has been attributed to different tissue reactivity.

Animals↗
PubMed1975

Fibrogenic response in murine lungs to asbestos.

Pulmonary fibrogenic response was investigated in mice following intratracheal inoculation of amosite, anthophylite and tremolite varieties of Indian asbestos and studies were made over a period of 150 days. At early periods all the varieties produced acute inflammatory reaction in the lungs. Thick reticulum fibers were encountered at later periods with amosite, while only thin reticulum fibers developed with anthophyllite or tremolite variety. The formation of asbestos bodies did not take place with any of the asbestos varieties even at 150 days. The deviation in the pulmonary fibrogenic response in mice has been attributed to species difference.

Acute Disease↗
PubMed1975

Biochemical changes caused by asbestos dust in the lungs of rats.

The contents of collagen, hexosamine, phospholipids, and cholesterol and the activities of acid and alkaline phosphatases, glutamic oxalo-acetate transaminase, glutamic pyruvate transminase, aldolase, hexokinase, and lactic dehydrogenase were determined in the lungs of rats 150 days after the intratracheal injection of amosite, anthophyllite, and chyrsotile. Anthophyllite did not cause any significant change, while amosite and chrysotile caused significant increases in the contents of collagen and mucopolysaccharides. Lactic dehydrogenase and acid phosphatase activities were increased by all the dusts, while the othe enzymes were not seriously affected. The biochemical significance of the findings in relation to abestosis was discussed.

Alkaline Phosphatase↗
PubMed1975

A study of the age factor in experimental silicosis in rats.

In order to study the progress of pulmonary silicosis in rats of different ages, intratracheal injections of (50 mg/150 g body weight) quartz dust of particle size less than 5 mu were given as a single dose and studies were made over a period of 180 days. The pulmonary macrophage reaction and phagocytosis in the younger age group of rats was different from that in the older animals at 30 days postinoculation. The formation of silicotic nodules was delayed in the younger animals. They consisted of thick reticulin fibers and some collagen fibers; in the older group of rats large silicotic nodules with dense collagination developed towards the termination of the experiment (180 days). The present results indicate a possible direct relationship between age and the development of experimental pulmonary silicosis in rats.

Age Factors↗
PubMed1975

Changes in free and bound amino acids in experimental silicosis.

The amino acid composition of lung, serum and liver in silicotic rats was studied in order to assess the availability of precursors in lung for fibrogenesis. It was observed that the pool of ornithine, arginine, alanine, leucine, valine, glutamic acid, lysine, proline and glycine underwent marked alterations. Free arginine, proline and leucine were only detectable in silicotic lung, while free glycine, glutamic acid and glutamine pools decreased significantly in liver. Changes in amino acid metabolism as a result of silicosis are discussed.

Amino Acids↗
PubMed1975

Enzymatic changes in lung tissue of asbestotic guinea pigs.

The changes in the activities of some mitochondrial and soluble enzymes in the lungs of guinea pig, caused by three varieties of asbestos dust 120 days after intratracheal injection, were studied. Marked increase was observed in mitochondrial cytochrome oxidase, diaphorase and malic dehydrogenase. Among the soluble enzymes, lactic dehydrogenase showed the maximum variation.

Acid Phosphatase↗