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Biomedical subjects

S Mashiach

Publications and source records attributed to S Mashiach.

At least 325 records · Page 18Linked to original sources
PubMed1986

Male to female ratio after gonadotropin-induced ovulation.

Two hundred fifty-six children were born in 195 births from 176 women that conceived after human menopausal gonadotropin/human chorionic gonadotropin (hMG/hCG)-induced ovulation. The secondary sex ratio was 50% male to 50% female births, which is not statistically different from the Israeli or Occidental population. The same trend was observed for single births and for twins. Thus, the data presented do not support the reports of increased numbers of female infants in those conceived after induction of ovulation. Factors that are expected to have been shown to affect sex ratio: maternal age at delivery, total number of ampules of hMG/hCG administered in the conceptional cycle, urinary estrogen levels on the day of hCG injection, degree of ovarian hyperstimulation syndrome, and time of insemination in relation to the basal body temperature rise were found to be insignificant. Thus, the hypothesis that a local hormonal environment (gonadotropin or estrogen levels) during hMG/hCG treatment possibly affects sex selection was not confirmed.

Body Temperature↗
PubMed1986

Periovulatory 17 beta-estradiol changes and embryo morphologic features in conception and nonconceptional cycles after human in vitro fertilization.

Thirty-one patients who became pregnant after in vitro fertilization were compared with a matched control group of 31 patients who underwent embryo transfer but did not conceive. During the follicular phase there was no difference in the mean daily estradiol (E2) levels between the pregnant and control groups. In 95% of the women who conceived, E2 continued to rise or plateau on the day after human chorionic gonadotropin (hCG) administration; this pattern was seen in only 62.5% of the control group. There were significantly more "regular" embryos (i.e., those with symmetric blastomeres and no visible cytoplasmic fragments) replaced in patients who became pregnant, compared with the control subjects (65.6% versus 47.0%, P less than 0.05). Embryo regularity was associated with preovulatory E2 pattern; falling E2 levels on the day after hCG administration were associated with transfer of only 18.8% of regular embryos in the control group, whereas in the conceptional cycles with rising E2 levels, 61.5% of the replaced embryos were morphologically regular (P less than 0.01). These results would indicate that changes in the follicular environment as reflected by peripheral E2 levels might affect the developmental potential of the human embryo.

Chorionic Gonadotropin↗
PubMed1986

Treatment-independent pregnancy after in vitro fertilization and embryo transfer trial.

This study indicates that SP occur in a higher percentage than theoretically expected after IVE-ET treatment, but it is not conclusive as to whether the SP is independent or a result of the treatment or operative laparoscopy. Our results are in agreement with those of previous studies that have shown that SP occur with almost all kinds of infertility. We therefore reject the previous suggestion of Steptoe, who argued that to prevent ectopic pregnancy from complicating embryo replacement, preparatory electrocauterization of diseased tube should be performed. We also suggest that as long as the results of treatment are below the normal monthly spontaneous conception rate, there is justification for a prospective random study that includes all diagnoses other than BTB. Such a study might help make any future selection of patients for treatment more appropriate.

Adult↗
PubMed1986

Ultrastructural characterization of human granulosa cells in stimulated cycles: correlation with oocyte fertilizability.

The fine structure of human granulosa cells (GC) obtained in the course of an in vitro fertilization procedure was correlated with oocyte fertilizability. The investigation was performed by light-microscopic and electron-microscopic examination of ultrathin sections and replicas of freeze-fractured material. GC associated with nonfertilizable oocytes (group I) had significantly smaller cell areas, tended to be tightly packed, and exhibited abundant intercellular gap junctions and adherence junctions. Multiple structural variations of cytoplasmic organelles were observed in comparison to cells associated with fertilizable oocytes (group II). Cells in group II tended to be widely dispersed, frequently contained interiorized gap junctional elements (annular junctions), and showed morphologic correlates of high steroidogenic activity. Structural dissimilarities between groups I and II were not consistently related to follicle size, as determined by volume of aspirated follicular fluid. In view of the sequential ultrastructural changes known to occur during follicular maturation and ovulation, it is concluded that GCs related to nonfertilizable oocytes were lacking structural correlates of luteinizing hormone/human chorionic gonadotropin responsiveness.

Adult↗
PubMed1986

Culture of human granulosa cells from an in vitro fertilization program: effects of extracellular matrix on morphology and cyclic adenosine 3',5' monophosphate production.

Human GCs obtained from patients undergoing an IVF procedure and treated with CC, hMG, and hCG, lack cAMP responsiveness to hCG stimulation in vitro. After 48 hours in culture, recovery of cAMP production was significantly higher in hCG-stimulated cells grown on dishes coated with ECM than in cells grown on uncoated dishes. This difference correlated with a higher degree of morphologic differentiation of cells cultured on ECM. It is concluded that ECM provides superior culture conditions for the recovery of hormone-stimulated cAMP production and the maintenance of morphologic differentiation of preovulatory GCs from stimulated cycles.

Adult↗
PubMed1986

Effect of blood contamination on the fluorescence polarization value of amniotic fluid lamellar bodies.

Estimation of fetal lung maturity by examination of amniotic fluid samples is unreliable in the presence of blood. Centrifugation of amniotic fluid at 10,000 X g separates the surfactant-containing lamellar bodies from contaminants, such as serum lipids. The influence of serum contamination of amniotic fluid was evaluated using the fluorescence polarization technique for determination of fetal lung maturity. Addition of serum changed the amniotic fluid P value of both the amniotic fluid and the lamellar body pellets in the direction of the P value of serum. After centrifugation at 10,000 X g, there was no significant difference in the P value of the pre- and postcontamination samples, demonstrating that centrifugation resulted in the removal of pulmonary nonrelevant lipids in contaminated amniotic fluid specimens. In 24 patients in whom the amniotic fluid sample was blood stained, the P value on the lamellar body pellet compared favorably to that obtained from noncontaminated samples.

Amniotic Fluid↗
PubMed1986

Regulation of rat granulosa cell differentiation by extracellular matrix produced by bovine corneal endothelial cells.

The effect of bovine corneal extracellular matrix (ECM) on gonadotropin-primed rat granulosa cells in vitro was studied by examining the following parameters: 1) rate of cell attachment to culture dishes; 2) modulation of cell morphology; 3) specific binding of [125I]human(h)CG to LH/hCG receptors; 4) cAMP response to hCG stimulation; and 5) basal and hCG stimulated progesterone production. Attachment of cells to culture dishes occurred significantly earlier on ECM, as compared with uncoated dishes (6 h vs. 24 h). Cells grown on ECM were epitheloid and organized in multilayer aggregates, closely resembling their organization in the intact wall of the ovarian follicle. In contrast, cultures on uncoated dishes grew as a monolayer of markedly flattened cells. A 2-fold increase in number of LH/hCG receptors occurred on ECM within 48 h, probably due to de novo synthesis. Scatchard analysis revealed no change in hormone affinity to the receptor during the culture period [association constant (Ka) = 2.5 X 10(10)M-1 for hCG]. Cells grown on ECM had a parallel increase in cAMP responsiveness to hCG stimulation. Cells grown in serum-free medium on ECM-coated dishes preserved only 50% of LH/hCG receptors and cAMP responsiveness after 48 h. Cells cultured on ECM showed a marked elevation in progesterone production even in the absence of gonadotropin stimulation, whereas cells grown on uncoated dishes almost completely lost their ability to produce progesterone both in the presence and absence of hCG. These results indicate that ECM plays a substantial role in the maintenance and further propagation of granulosa cell differentiation in vitro.

Animals↗
PubMed1986

Fertility after nonsurgical treatment of ectopic pregnancy.

There is no question that the treatment of choice for ectopic pregnancy is surgery. However, since some ectopic pregnancies terminate in tubal abortion or complete resorption, it is questionable whether surgery is necessary in every case. Some patients can be managed by monitoring rising or falling levels of beta-human chorionic gonadotropin (beta-HCG) until tubal abortion or resorption occurs. This approach, which may be the best means of preserving tubal function and fertility, was used in 14 patients who fulfilled extremely selective criteria. In some of the patients, surgery later proved to be necessary, but in 11 nonsurgical management was followed by a fall in beta-HCG levels, and there were no further untoward effects. Three of these patients subsequently developed intrauterine pregnancies, and one patient had a repeat ectopic.

Abortion, Missed↗
PubMed1986

Impact of a protocol for external cephalic version under tocolysis at term.

We present our experience with 60 trials of external cephalic version under tocolysis (EVT) performed on 58 women with uncomplicated (low-risk) pregnancies at term (37 to 42 weeks) during a 10-month period. Version was successful in 67.2% of the subjects (70.7% of trials). Fetal well-being was monitored before, during and after the procedure by cardiotocography and real-time ultrasound (RTUS). No analgetic or anesthetic medication was administered. Transient fetal bradycardia was recorded in 18 women. No major complications were noted. Compared with the period preceding the protocol, the breech rate declined during the study period by 1.02% (P less than 0.02) with a parallel decline of 1.12% (P less than 0.001) in the low-risk breech group affected by the protocol. The cesarean section rate for low-risk breeches fell from 1.85 to 0.89% (P less than 0.001), while the overall cesarean section rate decreased from 10.15 to 9.1% (not significant). We conclude from our experience and previous studies that EVT/RTUS is a reasonable alternative in the management of pathological presentations near term, provided that only low-risk pregnancies are included, and analgesia or anesthesia for external version under tocolysis is avoided.

Breech Presentation↗
PubMed1986

Reproductive outcome after microsurgical treatment of tubal pregnancy in women with a single fallopian tube.

Whether restoration of tubal function following conservative surgery for ectopic pregnancy was achieved can only be estimated in patients with a single tube. Between 1978 and 1983, 22 women with a tubal pregnancy in their single tube underwent conservative microsurgical treatment. In 18 women dorsal salpingotomy was performed, in 3 the tube was gently milked (squeezing the products of conception through the fimbria), and in 1 the segment containing the products of conception was excised and the tube anastomosed. Twenty-one patients desired pregnancy. The mean follow-up period was 21.4 months. Of the patients desiring pregnancy, 76% conceived. The intrauterine pregnancy rate was 47.6%, and the repeat ectopic pregnancy rate was 42.8%. This ectopic pregnancy rate was significantly higher than those quoted in recent literature. Although the study group was a very-high-risk group, restoration of tubal function was achieved in a high proportion of cases. The intrauterine pregnancy rate was high and higher than the best results available with in vitro fertilization and embryo transfer, which is the only treatment available after bilateral salpingectomy. Therefore, conservative surgery is definitely indicated in such patients despite the high incidence of repeat ectopic pregnancy.

Adult↗
PubMed1986

Determination of fetal lung maturity by fluorescence polarization of the amniotic fluid lamellar bodies.

High-speed centrifugation of amniotic fluid enables separation of surfactant-containing lamellar bodies. Fifty-three amniotic fluid samples from pregnancies of 28 to 39 weeks' gestation were examined for fetal lung maturity by measuring fluorescence polarization (P). For each sample the P value was determined at 37C on both the whole amniotic fluid and on the surfactant-containing lamellar bodies obtained by centrifugation at 10,000 X g. A close linear correlation (r = 0.80) was found between the P value of the amniotic fluid samples and that of the lamellar bodies. There was no difference in the specificity for discrimination of hyaline membrane disease cases by both methods (93.5%) with 95% confidence limits of 82.1 to 98.6%. Because high-speed centrifugation enables the selective sedimentation of pulmonary surfactant, determination of the lamellar body P value may offer a practical solution for the estimation of fetal lung maturity in amniotic fluid samples contaminated with blood.

Amniotic Fluid↗
PubMed1985

The effect of pressure on the lipid microviscosity and phase transition of lung surfactant.

The effect of pressure on the lipid dynamics of the rat lung surfactant was studied in liposomes made of the natural lung surfactant of the rat and of model phospholipid mixture. The determined parameter was the lipid microviscosity, monitored by the fluorescence polarization of the probe 1,6-diphenyl-1,3,5-hexatriene. Osmotic pressure of up to 47 atm, as well as hydrostatic pressure of up to 1.4 kbar, were applied at a constant temperature. The effect of pressure was monitored by the change in the lipid microviscosity of the system. The maximal change achieved with osmotic pressure at a constant temperature was only 30%. This suggests that the conversion of melted lipid to its solid phase above the lipid critical temperature requires several hundred atmospheres. Similarly, measurements of lipid microviscosity under increased hydrostatic pressure revealed transitions which occurred at above 400 atm. Since such pressures are far beyond the physiological scale, it excludes the possibility that pressure alone can be responsible for a full phase transition of the lung surfactant during respiration. Upon decompression, microviscosity of the examined lipid system was found to return to its original values, confirming the reversibility of the process.

Animals↗
PubMed1985

Excretion of total estrogens and estrone-3-glucuronide during treatment with human menopausal gonadotropins.

HMG treatment is usually monitored by the evaluation of the cervical mucus, the determination of plasma 17 beta-estradiol, total urinary estrogens, ultrasonographic evaluation or a combination of these. We evaluated the daily validity of estrone-3-glucuronide excretion in urine as an indicator of follicular growth and maturation in 28 infertile women who were treated with HMG (Pergonal 500). Total urinary estrogens and estrone-3-glucuronide were measured in 24 h urine collections, and 11 of the women collected the early-morning urine separately. This allowed comparison of the concentrations and excretion of total estrogens and estrone-3-glucuronide of the 24 h urine with that found in the urine collected overnight. This comparison was made on 83 urine samples. The correlation between either the total excretion per 24 h or the concentration per liter in the 24 h urine collection of the two systems of determination was good in all determinations. Also in the urine collected on the day prior to HCG administration, total estrogens measurement was in good correlation with the estrone-3-glucuronide. However, there was statistically a significant difference in the concentrations of total estrogens and estrone-3-glucuronide between the women who ovulated and those who did not. Estrone-3-glucuronide, when calculated as a percentage of the total estrogens, was 60.86% in the women who ovulated and 33.15% in those who did not. These results demonstrate that although estrone-3-glucuronide reflects ovarian function in women treated with HMG, it may serve as a better predictor to ovulation.

Chorionic Gonadotropin↗
PubMed1985

Penetration of sperm from teratospermic men into zona-free hamster eggs.

The ability of sperm samples from male partners of infertile couples, with isolated teratospermia (ITS), to penetrate zona-free hamster eggs was examined. The ITS patients had a significantly lower proportion of normal spermatozoa than did a control group of men of proven fertility (23.6% and 47.8%, respectively; P less than 0.001), while the mean total sperm count and the % motility did not differ between the two groups. The mean hamster egg penetration rate of sperm from ITS patients was 2.64% compared to 31.1% in the control group. A significant negative correlation was found in the ITS group between the proportion of a) abnormal forms and the ability to penetrate zona-free hamster eggs, and b) pyriform-shaped sperm and the penetration rate. Of the sperm parameters which were examined, only the morphology could be correlated with the rate of penetration.

Adult↗