PubMed Health⌕ Search

Biomedical subjects

A K Ray

Publications and source records attributed to A K Ray.

At least 73 records · Page 4Linked to original sources
PubMed1977

Effects of prostaglandins E2 and F2alpha on lecithin biosynthesis by cultured lung cells.

Transformed cells from human lung carcinoma (Line A549), resembling type II pneumocytes, were cultured in monolayer at 37 degrees C and incubated for five hours with 3H-choline and 14C-palmitate in the presence of various concentrations of prostaglandins (PGS) E2 and F2alpha. In the control (no PG) the level of % palmitate incorporation was 13.5 x as high as that of choline, after taking isotope dilution into account. Between the concentrations studied, 0.1 and 10 muM, both prostaglandins stimulated markedly the incorporation of both precursors, though choline up to 3 x better than palmitate. This was indicated by a change in the palmitate/choline incorporation ratio from 13.5 to as low as 4.2. At the lowest PG concentration, 0.1 muM, PGE2 was much more effective than PGF2alpha in stimulating the incorporation of both precursors.

Cell Line↗
PubMed1977

Morpho-histology of the alimentary canal of an Indian fresh-water perch, Colisa fasciata (Bloch) in relation to food and feeding habits.

The morpho-histology of the alimentary canal in an Indian freshwater perch, Colisa fasciata (Bloch) in relation to food and feeding habits has been described. C. fasciata is an omnivorous, mid-feeder. The mouth is protractile. The alimentary canal comprises the lip, buccal cavity, pharynx, oesophagus, stomach, pyloric caeca, a long and coiled intestine and the rectum. The teeth on the roof and floor of the buccal cavity, jaw teeth, pharyngeal teeth and horny pad teeth are all adapted to the nature of the food ingested. The nature and disposition of taste-buds and mucous cells on the lips suggests that the fish is a taste-feeder. The presence of taste-buds in the anterior oesophagus indicates that the gustatory sense extends upto the oesophagus. The stomach is divided into the cardiac and pyloric regions. The surface epithelium of the cardiac stomach secretes mucous and the glandular epithelium contains numerous gastric glands. The pyloric caeca are paired. The intestine is divided into anterior, middle and posterior regions. The R.L.G. (relative length of the gut) varies from 4--5. Mucosal folds are simple.

Animals↗
PubMed1976

Isolation of secretory IgA from a lung surfactant fraction.

Although dipalmitoyl lecithin, is the essential component of the pulmonary surfactant system that is invoked for alveolar stability, there is no explanation as yet for the origin and role of certain proteins that are found with the phospholipid in pulmonary washings. Aqueous lavages obtained from rabbit lung contain three major proteins, two of which are serum proteins (albumin 60%, gamma-globulin 10%), and the third, protein "T" (20%), is described here as pulmonary secretory immunoglobulin A (sIgA1. The protein is first recovered quantitatively in the surface active lipid-protein fraction from filtration of pulmonary lavage on Sephadex G-200. The protein is then isolated from the lipid either by filtration on SDS-Sephadex G-200 or by ethanol-ether precipitation. After reductive cleavage with either mercaptoethanol or dithiothreitol and alkylation with iodoacetamide, three protein peaks are obtained from SDS-sephadex G-200 separation. The products of reductive cleavage are analogous to the secretory component (MW approximately 60,000), H-chain (MW approximately 50,000), L-chain (MW approximately 25,000), and J-piece (MW approximately 28,000) of secretory IgA from colostrum. In immunodiffusion the lung protein and colostrum sIgA show striking identity lines, as do antibodies to rabbit colostrum and to the lung protein. Amino acid and carbohydrate analyses reveal some differences between the two secretory immunoglobulins. Although this protein has been found together with the phospholipid surfactant of the lung in vitro, the present structural study concludes that the protein is sIgA. Although concurrent immunofluorescence studies showed that this protein is in the alveolar lining layer, we cannot as yet conclude that it belongs to the surfactant system of the lung.

Amino Acids↗
PubMed1976

Histochemical studies on the effect of thyroid hormone on alkaline and acid phosphatase activities in liver of fish and amphibia.

The Lata fishes (Ophicephalus punctatus) showed increased alkaline and acid phosphatase activities in liver after immersion for 15-30 days in thyroxine-containing medium (0.025 mug/ml). A single injection of thyroxine (1-2 mug/g of body weight) caused increased acid phosphatase activity in liver of Lata fish in comparison to the controls on the 5th day after experiment but the alkaline phosphatase activity remained unchanged. Both alkaline and acid phosphatases showed increased activities in liver of Lata fishes treated with a single injection of 4 mug of thyroxine per g of body weight on the 5th day. Immersion of Lata fishes in thiourea solution (1 mg/ml) for 15 days did not show any alteration in alkaline or acid phosphatase activities but these enzyme activities decreased after 30 days' immersion in thiourea solution in comparison to the controls. A seasonal variation of alkaline and acid phosphatase activities was observed in liver of Lata fishes. More alkaline phosphatase activity was found in liver of summer fishes than in winter fishes. The winter fishes showed more acid phosphatase activity than the summer fishes. Three consecutive injections of thyroxine (0.1 mug/g of body weight) to toads (Bufo melanostictus) caused increased alkaline and acid phosphatase activities in liver on the 5th day of the experiment, in comparison to the controls.

Acid Phosphatase↗
PubMed1975

Population structure of the Juang tribe in Orissa, India.

The coefficient of kinship of the Juangs, a very primitive tribe in the state of Orissa in eastern India, is estimated. The Juang population is sub-divided into two breeding groups: one practising shifting cultivation in the hilly regions of the former state Keonjher and Pal-Lahara, called here "primitive group"; the other settled in Dhenkanal and practising normal Indian agriculture, called here "advanced group". From the migration matrix the mean eoefficient of kinship in a population subdivided by geographically restricted clans is estimated to be 0.0045 for the primitive group and 0.0324 for the advanced group. These values correspond to Alpine and Micronesian isolates, respectively. Estimates from genealogies of randomly paired sibships are substantially smaller (0.0016 and 0.0131, respectively), but are biased downward by incompleteness of pedigrees and by neglect of restricted migration within each group. Therefore the estimates from the migration matrix are presumably more reliable in this material, and perhaps commonly in tribal populations.

Ethnicity↗