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B B Paul

Publications and source records attributed to B B Paul.

13 recordsLinked to original sources

Positive correlation of optical density at 650 nm. with lecithin/sphingomyelin ratios in amniotic fluid.

In this study, we have attempted to correlate optical density measurements of amniotic fluids with L/S ratios. We may conclude, with over a 98 per cent accuracy, that fluids having optical density readings of 0.15 and above, at 650 nm. will have an L/S ratio over 2.0. Fluids having optical density readings up to 0.05 will have L/S ratios of about 1.3. Finally, amniotic fluids having optical densities greater than 0.05 and less than 0.15 will have L/S ratios of approximately 1.5.

Amniotic Fluid

Enhanced killing of myeloperoxidase-coated bacteria in the myeloperoxidase-H2O2-Cl- system.

Bacteria preincubated with myeloperoxidase (MPO) are more readily killed upon the addition of H2O2 and Cl- than controls not subject to prior incubation. This effect was evidenced by decreased requirements of MPO and H2O2 (to approximately 33%) for equivalent bactericidal activity. MPO adsorbed onto the bacterial surface is not accessible to other competing substrates such as guaiacol and [1(-14)C] alanine. It appears that when MPO is adsorbed to the bacteria, it carries out a coupled reaction in which the activated chlorine directly attacks the bacterial cell surface.

Chlorides

Response to mitogen during pregnancy and the postpartum period.

The influence of pregnancy, pregnancy plasma, and pregnancy-associated lhormones on the response of peripheral blood lymphocytes to two phytomitogens (PHS and PWM) was examined in a group of 17 healthy women during pregnancy and the postpartum period. No consistent disparity between pregnancy, postpartum, and control tests was noted in either intrinsic lymphocyte responsiveness or in the effect of autologous plasma or four pregnancy-associated hormones (estriol, progesterone, hPL, and estradiol-17 beta) on lymphocyte responsiveness.

Adolescent

Relation between optical density at 650 nm and L/S ratios.

A simple and rapid test that correlates with L/S ratios has been developed. By centrifuging fresh, unfrozen amniotic fluids at 200g for 10 minutes and measuring the optical density at at 650 nm, correlation with L/S ratios is obtained. Optical density readings of 0.15 or greater correlate 100% with L/S ratios of 2.0 or greater. Optical readings below 0.15 correlate 94% with L/S ratios below 2.0.

Amniotic Fluid

Chlorination, decarboxylation and bactericidal activity mediated by the MPO-H2O2-C1- system.

1. MPO, H2O2 and C1- form a complex that undergoes intramolecular rearrangement yielding the chlorinium ion. 2. The chlorinium ion can interact with MPO, bacteria and amino acids. 3. The reaction can occur at a wide range of pH, H2O2 concentration and C1- concentration. 4. The chlorinium ion can attack different protein molecules to cause structural changes. 5. Preincubation of MPO with bacteria results in greater bactericidal activity. 6. Diffusible bactericidal agents are also produced by the MPO-H2O2-C1- system.

Animals

Mouse spleen lymphocyte bactericidal and peroxidase activities: enhancement by whole body x-irradiation.

A 20,000 g pellet obtained from the homogenate of CD1 mouse spleen cells has measurable peroxidase and bactericidal activities. Whole body x-irradiation stimulates the in vitro peroxidative and bactericidal activities of the spleen cells. These cells do not phagocytize. However, addition of polystyrene latex particles to spleen cells from non- or x-irradiated mice, increases glucose oxidation. The extent of this stimulation (three- to fourfold) is less than that of PMN (six- to tenfold). Interaction between particles and lymphocyte surface may be the cause of this stimulation. The increased bactericidal activity due to x-ray is attributed mainly to an increase in the peroxidase activity of the lymphocytes. Surface (membrane) action rather than phagocytosis may be involved in the bactericidal process. The spleen lymphocyte peroxidase is distinct from myeloperoxidase in several respects.

Animals

Correlation between amniotic fluid optical density and L/S ratio.

A test that circumvents the complex methodology needed for the determination of L/S ratios has been developed. It has been observed that the optical density, measured at 400 nm, of supernatants collected from fresh amniotic fluids centrifuged at 2000 g for 10 minutes correlates with L/S ratios.

Amniotic Fluid