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Biomedical subjects

S Sahu

Publications and source records attributed to S Sahu.

At least 19 recordsLinked to original sources
PubMed1991

Living conditions and occurrence of malaria in a rural community.

Results of a prospective study of the association between environmental factors and malaria occurrence among 1461 individuals in an Indian rural community are reported. A multiplicative model was fitted by relating malaria positivity with different environmental risk factors as categorical variables. The risk of acquiring malaria infections varied significantly within a village stratified by proximity of breeding sources to human dwellings (chi 2 = 19.87, df = 5, p = 0.0000) and different types of houses (chi 2 = 11.32, df = 2, p = 0.0035). People residing in thatched houses with [Relative Risk (RR) = 6.72] and without false ceiling (RR = 11.27) are exposed to greater risk of contracting malaria infections when compared to tiled houses (RR = 1.00). However, malaria infection was not significantly associated with proximity of cattlesheds to human dwellings (chi 2 = 1.54, df = 2, p = 0.46). A significantly high risk was observed in zones where the cattle to man ratio was very low and vice versa (chi 2 = 15.32, df = 6, p = 0.018). These data suggest and corroborate with earlier studies that transmission is a local problem and it varies within a village according to the microepidemiological factors.

Adult↗
PubMed1979

Isolation and characterization of proteoglycans from porcine lungs.

Proteoglycans were extracted from porcine lungs with 4 M guanidinium chloride. The extract was subjected to associative density gradient centrifugation, and four equal fractions, labeled A1 through A4 from the bottom to the top of the gradient, were obtained. The pooled A1 fractions containing proteoglycan aggregates were further fractionated by dissociative density gradient centrifugation to yield four equal fractions labeled A1D1 through A1D4 from the bottom to the top of the gradient. These fractions were analyzed for their protein, uronic acid, glucosamine, galactosamine, hexose, and sialic acid content. The fraction A1D1 with the highest buoyant density had the highest content of uronic acid and galactosamine, and lowest content of protein, indicating the enrichment of proteoglycan monomers at the bottom of the dissociative density gradient. As the density of the gradient decreased, the protein, hexoses, and sialic acid content increased, whereas uronic acid and galactosamine content decreased. The amino acid analysis showed similar composition for all four fractions with aspartic acid, serine, glutamic acid, proline, glycine, alanine, valine, and leucine as the major constituent amino acids. No hydroxyproline was detected in any of the fractions. As the buoyant density of the fractions decreased, the aspartic acid content increased and glycine content decreased.

Amino Acids↗
PubMed1979

Characterization of a high-molecular-weight glycoprotein isolated from the pulmonary secretions of patients with alveolar proteinosis.

A high-molecular-weight glycoprotein was isolated, purified and partially characterized from the insoluble pulmonary secretions accumulating in lungs of patients suffering from pulmonary alveolar proteinosis. On electrophoresis in 5% polyacrylamide gel in the presence of sodium dodecyl sulphate and 2-mercaptoethanol, the purified protein gave one major band as detected by Coomassie Blue as well as with periodic acid/Schiff staining. An apparent mol.wt. of 250000 was estimated for this glycoprotein. Amino acid analysis showed that it contains hydroxyproline, and relatively high amounts of glycine, glutamic acid, aspartic acid and leucine. It contains approx. 6% hexose, 3% sialic acid and 2% glucosamine. The neutral sugars are galactose, mannose and fucose. An antiserum prepared in rabbits against this high-molecular-weight glycoprotein cross-reacted with two smaller glycoproteins (mol.wts. 62000 and 36000) isolated from the same pulmonary secretions of these patients. A complementary observation was also made when this large alveolar glycoprotein cross-reacted with an antiserum prepared in rabbits against the smaller glycoprotein (mol.wt. 36000). It appears that this high-molecular-weight glycoprotein may be the precursor of the two smaller glycoproteins present in the same diseased pulmonary secretions.

Amino Acids↗
PubMed1979

Characterization of a 130,000-dalton glycoprotein isolated from pulmonary secretions of patients with alveolar proteinosis.

A new glycoprotein with an apparent molecular weight of 130,000 was isolated, purified, and partially characterized from the pulmonary secretions which accumulate so massively in the lungs of patients suffering from pulmonary alveolar proteinosis. The amino acid analysis of the glycoprotein showed the presence of relatively high amounts of glycine, glutamic acid, aspartic acid, leucine, and valine, and small amounts of hydroxyproline, but no hydroxylysine. It contains approximately 6% hexose, 3% sialic acid, and 4% glucosamine. The neutral sugars are galactose, mannose, and fucose. This alveolar glycoprotein cross-reacted with an antiserum prepared in rabbits against a larger glycoprotein (250,000 mol wt) isolated from the same source, suggesting that the larger alveolar glycoprotein may be the precursor of the smaller one.

Amino Acid Sequence↗
PubMed1978

Hyaluronic acid in the pulmonary secretions of patients with asthma.

Hyaluronic acid was the only glycosaminoglycan found in the pulmonary secretions of patients with asthma. The compound had a hexuronate/hexosamine molar ratio of about 1:1. Glucosamine constituted over 98% of the hexosamines, the remaining being galactosamine. The compound moved as a single spot with the mobility of standard hyaluronic acid on cellulose acetate electrophoresis, and this spot disappeared after digestion with testicular hyaluronidase. Even after extensive proteolysis and purification, the compound was associated with small amounts of protein, the major amino acids of which were aspartic acid, threonine, serine, glutamic acid, glycine and valine.

Adult↗
PubMed1978

Hyaluronic acid in the pulmonary secretions of patients with alveolar proteinosis.

Hyaluronic acid was the only glycosaminoglycan found in the pulmonary secretions of patients with alveolar proteinosis. The compound gave a hexouronate/hexosamine molar ratio of about 1:1. Glucosamine constituted over 98% of the hexosamines, the remaining being galactosamine. It moved as a single spot with the mobility of standard hyaluronic acid on cellulose acetate electrophoresis, and this spot disappeared after digestion with hyaluronidase. It was associated with small amounts of proteins, the major amino acids of which are aspartic acid, glutamic acid, glycine, alanine, and leucine.

Amino Acids↗
PubMed1978

Lipid composition of sputum from patients with asthma and patients with cystic fibrosis.

Lipids from the sputum of patients with asthma and with cystic fibrosis were isolated and characterized. In both cases, lipids constituted approximately 30% of the dry material. Phosphatidlycholine was the most abundant lipid, Significant amounts of phosphatidylethanolamine and phosphatidylglycerol were present. Hexosyl ceramides, sphingomyelin, phosphatidylinositol, lysophosphatidylcholine, and lysophosphatidylethanolamine were present as minor lipid components. Apperciable quantities of neutral lipids were present, of which triglycerides and cholesterol were the main constituents. Phosphatidylcholine, sphingomyelin, and phosphatidylgycerol were highly saturated. Large amounts of phosphatidylcholine containing mostly palmitic acid, particularly in the asthmatic sputum, suggest htat this highly saturated. Large amounts of phosphatidylcholine containing mostly palmitic acid, particularly in the asthmatic sputum, suggests that this highly saturated phospholipid is synthesized in the upper airways for reasons other than its beneficial surface-active properties in the alveoli.

Adolescent↗
PubMed1977

Characterization of phospholipase A from pulmonary secretions of patients with alveolar proteinosis.

Phospholipase A2 (EC 3.1.1.4) from the insoluble pulmonary secretions that accumulate in the lungs of patients with alveolar proteinosis has been purified. The pure enzyme gives a single sharp band upon sodium dodecyl sulfate polyacrylamide gel electrophoresis. Amino acid analysis of the protein shows high content of cystine, aspartic acid, glutamic acid, serine, glycine, leucine and lysine. Only one N-terminal residue, alanine, can be detected. Gel filtration as well as sodium dodecyl sulfate polyacrylamide gel electrophoresis indicate an apparent molecular weight of 75 000 for the enzyme. The enzyme activity has a pH optimum between 7.5 and 8.5 and is stimulated by sodium deoxycholate and CaCl2.

Amino Acids↗
PubMed1977

Metabolism of arachidonic acid in rabbit alveolar macrophages.

Rabbit alveolar macrophages incorporated radioactive arachidonic acid primarily into phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, and triglycerides. When these cells, so labelled, were washed and treated with polystyrene beads, there was a distinct and reproducible decrease in the radioactivity of phosphatidylcholine, phosphatidylethanolamine, and triglycerides. This decrease was accounted for by the appearance of two major prostaglandins, PGE2 and PGF2alpha, and uncharacterized hydroxy fatty acids, which may be 12-hydroxy-5,8,10,14-eicosatetraenoic acid, 5-hydroxy-6,8,11,14-eicosatetraenoic acid, and/or 8-hydroxy-9,11,14-eicosatrienoic acid.

Animals↗
PubMed1977

Lipid chemotaxins isolated from culture filtrates of Escherichia coli and from oxidized lipids.

Lipid extracts of sterile culture filtrates of Escherichia coli were shown to contain approximately 75% of the chemotactic activity for human polymorphonuclear leukocytes and rabbit alveolar macrophages. Fractionation and purification of these lipids revealed the presence of many unknown lipids of widely different properties, but all were anionic and at very low concentrations, chemotactic. The only one of active molecules that could be identified was an unsaturated ultraviolet-absorbing hydroxy fatty acid, which, following catalytic reduction with hydrogen, was found to be hydroxyeicosanoic acid. This fatty acid's chromatographic behavior was very similar to that of 12-hydroxy-5,8,10,14-eicosatetraenoic acid (HETE), which is a potent chemotaxin for polymorphonuclear leukocytes and macrophages. Unknown chemotaxins could be generated by the oxidation of known unsaturated lipids. Prostaglandins A2 and E2 produced potent chemotaxins upon aerobic oxidation. Malonaldehyde, a peroxidation product of unsaturated lipids, when reacted with phosphatidylethanolamine in aerobic conditions, also produced strong chemotactic agents. The chemotactic activity of these products could be destroyed by catalytic reduction with hydrogen and by methylation with dry methanolic HCl. These data indicate that the nonenzymatic oxidation of unsaturated lipids generates some products that are potent chemotaxins for mammalian inflammatory cells.

Animals↗
PubMed1977

Lipid composition of airway secretions from patients with asthma and patients with cystic fibrosis.

Lipids from the particulate material obtained from pulmonary lavage of patients with asthma and cystic fibrosis were isolated and characterized. In both cases, lipids constituted 30 to 40 per cent of the dry insoluble material and phosphatidylcholine was the predominant lipid. Significant amounts of phosphatidylethanolamine and phosphatidyglycerol were present. Hexosyl ceramides, spingomyelin, phosphatidylinositol, phosphatidylserine, and lyso(bis)phosphatidic acid were present as minor lipid components. Appreciable quantities of neutral lipids were also found. Significant amounts of lysophosphatides and free fatty acids were present only in the lavage sediment from patients with asthma, and not in patients with cystic fibrosis. Phosphatidylcholine, lysophosphatidycholine, sphingomyelin, and phosphatidylglycerol of asthmatic lavage, but not cystic lavage, were highly saturated, containing mostly palmitic acid.

Adolescent↗
PubMed1977

Histochemical studies on the spinal cord of the Indian buffalo (Bubalus bubalis).

The distribution pattern of glycogen, alkaline phosphatase and acid phosphatase has been studied and recorded in normal and operated spinal cord of the Indian buffalo (Bubalus bubalis). Based on the observations, the following conclusions have been arrived at i) Glycogen is present in the cytoplasm and on the surface of the spinal neurons. Following injury, it is depleted from these sites. ii) Alkaline phosphatase is located in the nucleus and on the neuronal surface. It is not traceable at these sites following spinal cord injury. iii) Acid phosphatase is mostly confined to the neuronal cytoplasm and tends to increase in injured neurons.

Acid Phosphatase↗
PubMed1976

Light-induced absorption changes in photosystem I at low temperatures.

Light-induced absorption changes associated with the primary photochemical reaction and dark relaxation in Photosystem I were measured at various low temperatures. A possible temperature-dependent long-range electron tunneling process was suggested to account for the unique temperature dependence of the dark decay process. The kinetics of the light-induced absorption changes are in good agreement with the light-induced EPR changes reported earlier (Ke, B., Sugahara, K., Shaw, E.R., Hansen, R. E., Hamilton, W. D. and Beinert, H. (1974) Biochim, Biophys. Acta 368, 401--408) for the same Photosystem I subchloroplast fragment at comparable temperatures. All absorption changes between 400 and 725 nm at 86degreesK have identical kinetics. The light-minus-dark difference spectrum is very similar to that of P-700 at room temperature, with an additional prominent positive change at 690 nm. Possible contributions by P-430 to the blue and red spectral changes were discussed. It was demonstrated that the intensity of the measuring beam has a drastic effect on the light-induced absorption changes of Photosystem I at low temperatures. Various pretreatments of the Photosystem I fragments such as those that photochemically (or chemically) oxidize the primary donor or photoreduce the primary acceptor abolish the subsequent photochemical reaction. Continuous illumination of the Photosystem I fragments before and during freezing has the same effect. In the temperature range of --20 to --60degreesC, an unusual counter absorption change as well as a counter EPR change were observed.

2,6-Dichloroindophenol↗