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Biomedical subjects

H Schulman

Publications and source records attributed to H Schulman.

At least 217 records · Page 12Linked to original sources
PubMed1978

Ca2+-dependent protein phosphorylation system in membranes from various tissues, and its activation by "calcium-dependent regulator".

Analysis of membranes from a variety of tissues has revealed a widespread distribution of a protein phosphorylation system dependent on the presence of both Ca2+ and "calcium-dependent regulator" (CDR). This protein phosphorylation system has been studied in some detail in nervous tissue. Neuronal membranes contain a protein phosphorylation system that requires Ca2+ and a soluble heat-stable protein [Schulman, H. & Greengard, P. (1978) Nature (London) 271, 478--479]. This protein has been purified to homogeneity from bovine cerebral cortex, with use of an assay based on its ability to stimulate Ca2+-dependent protein phosphorylation in membranes. This protein kinase activator appears to be identical to CDR of cyclic nucleotide phosphodiesterase. Throughout its purification, this single entity was found to activate both Ca2+-dependent protein kinase and cyclic nucleotide phosphodiesterase. The kinase activator purified here and authentic CDR were equally effective in their ability to activate Ca2+-dependent protein kinase.

Animals↗
PubMed1978

Unruptured interstitial pregnancy. Diagnosis and treatment.

Symptoms and signs of interstitial pregnancy cannot be differentiated from symptoms and signs of other ectopic pregnancies. Unruptured interstitial gestations are usually diagnosed incidental to the work-up of a suspected ectopic gestation. Unlike some teaching, a characteristic pelvic mass was palpable in 3 of 4 cases. Incomplete induced abortion helped in diagnosing 2 cases. Ultrasound and laparoscopy will aid in establishing the correct diagnosis.

Adult↗
PubMed1978

Deceleration/contraction ratios as an index of fetal health during labor.

Internal FHR tracings of 259 patients with variable decelerations and 49 with late decelerations were analyzed for frequency and severity of the pattern in an attempt to correlate with fetal pH or Apgar score at 1 minute. A significant increase in the risk of fetal acidosis was associated with a frequency of greater than 30% variable decelerations and 20% late decelerations. It also increased with the increase of severity of the pattern. Variable decelerations are not good predictors of Apgar scores less than or equal to 6 at 1 minute, but late decelerations are predictive when they occur more than 20% of the time. The fetus with variable decelerations a normal pH can be observed through the first stage of labor with a high degree of confidence. However, when a 20% or more moderate-to-severe late deceleration/contraction ratio is present, intervention is necessary even if scalp blood pH is normal. The FHR deceleration/uterine contraction (UC) ratio is a simple bedside technique for assessing fetal outcome.

Acidosis↗
PubMed1978

Postpartum uterine pressures under halothane or enflurance anesthesia.

Postpartum uterine pressures were measured in healthy women with an intrauterine microballoon before, during, and after administration of different concentrations of halothane or enflurane. Arterial blood samples for anesthetic levels were obtained at intervals. Frequency and intensity of contractions diminished markedly when blood levels exceeded the equivalent of 1/2 MAC (minimum alveolar anesthetic concentration which produces immobility in one-half of subjects exposed to a noxious stimulus) of nonpregnant adults, but normal patterns returned promptly on lightening of anesthesia. Response to 10 mU of oxytocin was suppressed at blood levels corresponding to between 3/4 and 1 MAC of the agents. Halothane and enflurane exert equipotent dose-related reversible effects on the activity of the full-term pregnant human uterus.

Anesthesia, Inhalation↗
PubMed1977

Quantitative analysis in the oxytocin challenge test.

A quantitative analysis of the oxytocin challenge test (OCT) was carried out in 305 women to evaluate: (1) the intrauterine pressures evoked during the oxytocin infusion, (2) when fetal heart rate (FHR) decelerations are likely to occur, (3) the type and amount of decelerations which are significant, and (4) what clinical events and laboratory parameters correlate with the OCT. If contractions are evoked at a rate of three per 10 minutes, the pressure profile mimics normal labor. The first FHR deceleration is likely to occur between the second and third effective contraction. A deceleration/contraction ratio greater than or equal to 10% significantly forecasts an abnormal FHR during parturition and an increased chance of a cesarean section.

Adult↗
PubMed1977

Identification of UDP-glucose as an intermediate in the biosynthesis of the membrane-derived oligosaccharides of Escherichia coli.

The membrane-derived oligosaccharides of Escherichia coli constitute a closely related family of oligosaccharides containing approximately 9 glucose units variously substituted with sn-glycero-1-phosphate and phosphoethanolamine residues derived from the head groups of membrane phospholipids, and also with succinate in O-ester linkage (Kennedy, E.P., Rumley, M.K., Schulman, H., and van Golder, L.M.G. (1976) J. Biol. Chem. 251, 4208-4213). Studies with mutant strains defective in the synthesis of various nucleoside diphosphate sugars have now revealed that UDP-glucose is an essential intermediate in the biosynthesis of these oligosaccharides. Mutants unable to synthesize UDP-glucose do not contain significant amounts of the membrane-derived oligosaccharides. In contrast, a strain unable to synthesize ADP-glucose, the glucosyl donor for glycogen synthesis in E. coli, contained normal amounts of the membrane-derived oligosaccharides, although with a somewhat different pattern of distribution of the various subspecies. In confirmation of these genetic studies, pulse-label isotope tracer studies have been carried out with glucose of high specific activity, under conditions in which UDP-glucose comprises a large fraction of the total radioactivity in the low molecular weight pool. Subsequent "chase" experiments clearly revealed the conversion of UDP-glucose to the higher molecular weight membrane-derived oligosaccharides.

Cell Membrane↗
PubMed1977

Cortisol levels in amniotic fluid in prostaglandin F2alpha-induced midtrimester abortion.

Cortisol concentrations in amniotic fluid and maternal plasma were determined by a competitive protein-binding assay in 14 patients in the midtrimester of pregnancy before and after intra-amniotic administration of prostaglandin F2alpha. Samples were obtained at three-hour intervals until abortion or until the fetal heartbeat ceased. The mean plasma levels of cortisol increased from 324 +/- 173 ng. per milliliter at hour 0 to 524 +/- 272 ng. per milliliter at 6 hours (the peak elevated value). In amniotic fluid, the mean levels of cortisol increased from 4.71 +/- 2.5 ng. per milliliter to a maximum at 9 hours of 10.24 +/- 2.5 ng. per milliliter. We concluded that at 16 to 20 weeks' gestation the fetoplacental unit is capable of responding to prostaglandin F2alpha instillation by increased levels of cortisol in the amniotic fluid.

Abortion, Induced↗
PubMed1977

The effect of ritodrine on PgE levels in pregnant rabbit vena cava blood.

A chronic model was utilized in the rabbit to determine the effect of ritodrine hydrochloride infusions on pregnancy. Infusions were carried out for 6 hours in the unanesthetized, conscious animal between the 25 to 27 day of pregnancy. Pre and post infusion blood samples were drawn from a catheter lying at the lower inferior vena cava and analyzed for prostaglandin E and F, and progesterone. As compared to a control animal, there was a significant fall in prostaglandin E after 6 hour infusion of drug, but no change in prostaglandin F or progesterone was observed.

Animals↗
PubMed1976

Identification of sn-glycero-1-phosphate and phosphoethanolamine residues linked to the membrane-derived Oligosaccharides of Escherichia coli.

A previous report from this laboratory (van Golde, L.M.G., Schulman, H., and Kennedy, E.P. (1973) Proc. Natl. Acad. Sci. U.S.A. 70, 1368-1372) described the discovery in Escherichia coli of a novel class of oligosaccharides, containing glucose as the sole sugar, substituted with glycerophosphate units derived from membrane phospholipids, and with succinic acid in O-ester linkage. These membrane-derived oligosaccharides, comprising about 0.5 to 1.0% of the dry weight of E. coli, represent a family of closely related oligosaccharides that may be subfractionated on anion exchange resins. The present paper describes studies of the oligosaccharide A-1 described by van Golde et al. in the previous report. The glycerophosphate linked to the oligosaccharide in phosphodiester bond is the sn-glycero-1-P enantiomer. This finding strongly supports the previous conclusion that the oligosaccharides are the acceptors of the polar headgroups of membrane phospholipids, since the unesterified glycerophosphate of phosphatidyl glycerol is an sn-glycero-1-P residue, otherwise rare in nature. The glycerophosphate residues in the membrane-derived oligosaccharide are not substituted in the sn-2 or sn-3 positions, since they are readily oxidized by periodate under mild conditions. Alkaline hydrolysis liberates glycerophosphate, and only negligible amounts of free glycerol, consistent with the view that the glycerophosphate residues are linked to glucose units through position 6, unfavorable for the formation of glucose cyclic phosphate intermediates that would eliminate free glycerol. Oligosaccharide A-1 (but not Fraction A-2) contains phosphoethanolamine residues equivalent to 30 to 40% of the total phosphorus. The phosphoethanolamine residues are linked to position 6 of glucose units, as proved by the isolation of glucose 6-phosphate as a product of partial acid hydrolysis.

Alkaline Phosphatase↗
PubMed1976

Possible effect of maternal promethazine therapy on neonatal immunologic functions.

The effect of the administration of promethazine in the treatment of erythroblastosis fetalis was studied in four maternal-fetal pairs. The three infants exposed for a prolonged period of time had decreased neonatal number and function of T cells, and abnormal specific humoral immune responses. The possible role of promethazine in the induction of fetal immunoincompetence is discussed.

Antibodies↗
PubMed1976

Dynamics of contraceptive failures.

The purpose of this study was to explore the vicissitudes of contraceptive efforts and practice, and human behavior contributing to contraceptive failure. A consecutive sample of 481 women, who visited various gynecological out-patient clinics of a New York City municipal hospital between August 1974 and August 1975, served as the study population. There were 181 women with planned pregnancies and 300 women with unplanned pregnancies. The data were gathered in personal interviews. By comparison of both groups it was discovered that the women with unplanned pregnancies, because of their lower frustration tolerance level, had been led by successive difficulties related to contraceptive efforts and practice to episodic, faulty, or nonuse of technically effective contraceptive methods. Thereafter, psychological processes and mechanisms gave rise to a false sense of security, which virtually prevented them from resuming contraceptive practice. These psychological processes and mechanisms also govern other spheres of human behavior and merit systematic investigation.

Adult↗
PubMed1976

Studies of maternal plasma prolactin and amniotic fluid prolactin. Effects of chlorpromazine and prostaglandin F2alpha.

We have studied the effect of chlorpromazine and PGF2alpha on the blood and amniotic fluid levels of prolactin over a 1-hour period of time in women who were in the 14th-20th week of gestation. Following intramuscular injection of chlorpromazine, maternal plasma prolactin rose 1.0- to 2.5-fold. No significant change was noted in maternal plasma after PGF2alpha administration. Amniotic fluid prolactin declined by 6 to 56%. These changes may be dilutional.

Amniotic Fluid↗
PubMed1976

Electronic fetal monitoring during labor.

Intrapartum electronic fetal monitoring tracings from 620 women monitored internally over 60 minutes were analyzed. Fetal heart rate patterns were statistically analyzed against four variables of labor: 1) the presence of meconium; 2) fetal acidosis; 3) 1-minute Apgar score; and 4) clinical correlates considered as etiologic factors in FHR decelerations. No significant etiologic correlation was found between these clinical correlates and FHR deceleration patterns. Statistically significant correlations were established between poor neonatal outcome and fetal acidosis (P less than 0.01) and the presence of meconium (P less than 0.05). No correlation was found between FHR patterns and fetal acidosis. Variable deceleration showed no significant relation to low Apgar score (less than or equal to 6). Late deceleration showed a significant correlation with depressed infants. FHR patterns are best used as an alarm system of fetal difficulty than as an absolute measure of fetal distress.

Acidosis↗
PubMed1976

A histologic study of the placentas of patients with saline- and prostaglandin-induced abortion.

A comparative histologic study of plancentas aborted after infusion of hypertonic saline or prostaglandin F2alpha into the amniotic cavity toinduce abortion is presented. Five placentas from spontaneous abortions served as controls. Saline abortion produced edema of the membranes; congested,dilated, thrombotic blood vessels; and subchorionic necrosis. Prostaglandin did not produce edema, but created marked vasospasm as evidenced by thickened vessels without subchorionic necrosis. The absence of serious sepsis and defibrination in prostaglandin-induced abortions is probably related to the absence of tissue necrosis.

Abortion, Induced↗
PubMed1976

Routine amnioscopy at term.

A controlled study for the management of antepartum meconium-stained amniotic fluid (MSAF) detected by amnioscopy performed in a total of 508 patients is presented. The incidence of antepartum MSAF was 2.2%, while intrapartum MSAF was found in 15% of cases. A significant incidence of depressed neonates was found in the latter group. Patients with antepartum MSAF had no perinatal losses, whether managed expectantly or by oxytocin induction. Immediate operative intervention (ie, cesarean section) is not warranted. Observations on FHR patterns, fetal pH, and Apgar scores of these patients are presented.

Apgar Score↗
PubMed1976

Progesterone levels in amniotic fluid and maternal plasma in prostaglandin F2alpha-induced midtrimester abortion.

Progesterone concentrations in amniotic fluid and maternal plasma were determined in 11 midtrimester pregnant patients following the intraamniotic administration of prostaglandin F2alpha. Samples were obtained at 3-hour intervals until abortion or spontaneous rupture of membranes occurred or fetal heart tones disappeared. In amniotic fluid, the mean progesterone concentrations increased throughout the sampling period. The plasma progesterone levels declined by about one-third of basal values in the first 3 hours after prostaglandin administration. The paradoxic increase in amniotic fluid progesterone is probably secondary to alterations in uterine blood flow and intrauterine pressure.

Abortion, Induced↗