Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

Human cervical mucus. III. Isolation and characterization of rheologically active mucin

Several common mucolytic agents were screened for their ability to solubilize cervical mucus without incurring irreversible losses in mucus viscoelasticity. Sodium thiocyanate was selected on the basis of its effectiveness and handling convenience, and solubilized mucus was fractionated by gel filtration on Sepharose columns. The excluded mucin fraction was characterized by a high neutral hexose to protein ratio and contained all of the elasticity of thiocyanate-treated whole mucus. The concentration of mucin in individual mucus samples collected throughout the ovulatory menstrual cycle was determined from column elution profiles. An increased relative amount of mucin was associated with samples collected during the ovulatory phase of the cycle, and a strong correlation was obtained when the percentage of mucin in individual samples was plotted against their respective storage moduli. These results indicate that the cyclic fluctuations in mucus viscoelasticity seen previously at constant concentrations of nondialyzable solids can be attributed to variations in mucin concentration. Evidence was also obtained, however, for compositional differences in mucus derived from different patients.

Antidiuretic hormone levels during cardiopulmonary bypass

The effect of CPB on plasma ADH levels, urine flow, and urine osmolality was studied in nine patients. All patients received morphine, 1 mg. per kilogram, and 50 per cent nitrous oxide-50 per cent oxygen for anesthesia. CPB utilized a Travenol disposable bubble oxygenator and the prime consisted of 3 L. of Ringer's lactate. Measurements were made prior to induction of anesthesia , at 30 minutes following surgical incision, and at 15, 30, and 45 minutes during CPB. There were no statistically significant changes in mean arterial BP, cardiac index, serum sodium, or serum osmolality in any period. Urine flow increased from 0.99 +/- 0.3 ml. per minute to a high of 6.13 +/- 2.0 ml. per minute at 30 minute at 30 minutes on CPB (P less than 0.02). Urine osmolality declined from a control value of 691 +/- 142 mOsm. per kilogram to a low of 425 +/- 48 mOsm. per kilogram at 45 minutes on CPB (p less than 0.05). ADH levels rose from a control value of 4.3 +/- 1.5 to 13.0 +/- 3.3 pg. per milliliter with surgical stimulatiion (p less than 0.05). During CPB the ADH levels rose to a peak of 23.7 +/- 3.6 pg. per milliliter at 30 minutes (p less than 0.01) and were declining at 45 minutes. These data suggest that the stress of CPB results in an outpouring of ADH (or vasopressin) to function as a pressor to produce an increase in peripheral resistance. The ADH concentrations far exceed those required for normal physiologic control of water excretion and the urineflow will thus vary more with the hemodynamic changes than with the ADH levels.

Radioimmunoassay of antidiuretic hormone during morphine anaesthesia

The effect of morphine anaesthesia on plasma antidiuretic hormone levels was studied in seven adult patients. Measurements of ADH showed no significant change with morphine and 50 per cent nitrous oxide. Significant elevation occurred with surgical stimulation as previously reported. Changes in urine flow with high doses of morphine are then not ADH related.

On the role of prostaglandins in parturition in the rat

Treatment of both intact and hypophysectomized pregnant rats on days 19 and 20 of pregnancy with PGF2alpha results in a rapid fall in plasma progesterone concentrations by day 20 followed by premature delivery on day 21. Administration of depoprovera did not prevent the PGF2alpha-induced fall in progesterone levels but premature littering was adverted. Indomethacin, an inhibitor of prostaglandin biosynthesis, postponed the onset of parturition by 20 h when administered in late pregnancy but rats treated with both indomethacin and PGF2alpha delivered at the normal time. Treatment of both intact and hypophysectomized animals with indomethacin delayed the fall in plasma progesterone concentrations which normally occurs between days 21 and 22 of pregnancy. Concomitant PGF2alpha treatment of rats receiving indomethacin caused plasma progesterone levels to fall in a pattern similar to controls. These findings indicate that endogenous PGF2alpha induces a fall in blood progesterone concentrations which is followed by increased myometrial activity.