Biomedical subjects
Publications and source records attributed to S Rotmensch.
Doppler velocimetry of the fetal and maternal circulation can provide important diagnostic and prognostic information. However, the precise role of this technology in screening, diagnosis, and management of perinatal complications is still evolving. This article discusses some principles of physics, techniques, clinical applications, and limitations of Doppler velocimetry in obstetrics.
A causal link between hypothyroidism and spontaneously occurring ovarian hyperstimulation syndrome is suggested by analysis of data from a patient with myxedema and review of data from animal research.
Few other specialists in medicine are as exposed to body fluids as obstetricians. Anxiety among these health care providers is therefore considerable. Guidelines for universal infection precautions are aimed at minimizing the risk of human immunodeficiency virus transmission by the creation of adequate physical barriers between the patient and the health care provider. Some of these guidelines are mutually exclusive to currently popular childbirth techniques in the very practical sense. However, the more important impact of universal infection precautions is likely to be psychological. Anxiety and the necessity for physical isolation are probably the worst basis for an empathic human relationship with the patient. It is the current challenge of obstetrics to maintain a sensitive and client-centered approach while judiciously dealing with the acquired immunodeficiency syndrome epidemic.
Studies on the dynamic biochemical and morphological events occurring during steroidogenesis in granulosa cells suggest that the organization and expression of the actin-cytoskeleton may play a major role in the transduction of endocrine and paracrine steroidogenic signals, and in the coordination between the organelles involved in this process. Since steroid hormones are not stored intracellularly, regulation of their production is dependent mainly on the expression of genes coding for membrane-bound steroidogenic enzymes. Recently, the expression of oncogenes of the ras family was also implicated in the regulation of steroidogenesis.
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The effects of extracellular matrix (ECM) in the form of a native basement membrane and of hCG on progesterone production, cellular morphology, and gap junction formation in cultured human granulosa cells (GCs) were examined. GCs were harvested from human preovulatory follicles in the course of oocyte retrieval for in vitro fertilization. Cells grown on ECM secreted by bovine corneal endothelial cells (BCE) produced significantly higher amounts of progesterone (up to 3-fold) than cells on uncoated dishes. Culturing of cells on BCE-ECM in the presence of hCG resulted in a further increase in progesterone production; in the first 2 days an additive effect was noted, and on days 3, 4, and 5 a synergistic effect became evident (1.2- to 1.8-fold above the sum of the individual treatments). LH/hCG receptor content on day 3 of culture was 4-fold higher in GCs grown on BCE-ECM compared to that in uncoated dishes. A similar elevation was found when cells were grown on ECM secreted by PFHR-9 mouse endodermal cells. Cells grown on both types of ECM maintained their epithelioid shape but, in addition, formed cytoplasmic processes interconnected with neighboring cells by gap junctions. Morphometric analysis revealed that the area of cell membrane occupied by gap junctions increased by 3- to 4-fold on ECM compared to that in cells grown on plastic. Enlargement of endoplasmic reticulum was evident on ECM along with clustering of numerous mitochondria, lipid droplets, and lysosomes characteristic of highly luteinized cells. Cells grown in the presence of hCG on ECM showed morphological modulation similar to that of cells cultured on ECM alone. These observations suggest that growing of human GCs on a ECM similar to a naturally produced basement membrane enhances morphological and biochemical differentiation, and that ECM and gonadotropin affect synergistically the extent of luteinization in these cells.
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Interstitial pregnancy is an uncommon variety of ectopic gestation. Rupture tends to occur later than with tubal gestations, and is often associated with catastrophic hemorrhage. Few case reports of term interstitial pregnancies have been reported, and none have been associated with fetal survival. This is the first reported case of a term interstitial pregnancy resulting in a live infant.
Nonoperative direct examination of the pancreaticobiliary system with an ultrathin fiberoptic endoscope was compared to endoscopic retrograde cholangiopancreatography (ERCP). Thirty-one patients were examined by both techniques. Direct examination of the biliary system was successful in 12 patients, seven of whom had had previous endoscopic sphincterotomy. In two patients it revealed stones missed on ERCP. In none of the patients was an examination of the pancreatic duct possible. ERCP visualized the biliary system in 28 patients and the pancreatic duct in 30 patients. In one patient the ERCP revealed a stone missed by the peroral choledochoscopy. Peroral choledochoscopy is complementary to ERCP and should be reserved for patients with probable pathology of the biliary tract and normal ERCP.
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Cardiac arrhythmia is one of the most common reasons for cardiac consultation during pregnancy. Fortunately, malignant arrhythmias during the course of normal gestation are rare, and the relatively common complaint of palpitations is usually due to benign arrhythmias. However, in pregnant patients with organic heart disease, arrhythmias are often triggered by the haemodynamic burden of pregnancy and may be the first manifestation of the disease. In addition, rhythm abnormalities in patients with limited cardiac reserves may have significant haemodynamic consequences and can compromise fetal well-being. Any woman who presents with rhythm disorders during pregnancy should undergo a diagnostic evaluation to rule out an underlying disease, including cardiac, pulmonary, endocrine, or metabolic disease. Additionally, removal of precipitating factors, such as excessive ingestion of caffeine and/or alcohol, cigarette smoking, drug abuse or therapy with arrhythmogenic compounds, is indicated (as these measures are desirable in any pregnant woman). Antiarrhythmic drug therapy is indicated in such patients only in symptomatic or haemodynamically significant arrhythmias. In cases where organic heart disease or any other cause for arrhythmia is identified, the underlying disease should be treated first. Antiarrhythmic drug therapy is indicated when arrhythmias persist or as a prophylactic measure. In principle, the approach to drug therapy in pregnant patients is similar to that in non-pregnant patients. However, special consideration should be given to drug selection in order to avoid adverse effects to the fetus. Those antiarrhythmics that have been shown to be relatively safe during pregnancy include digoxin, quinidine, procainamide, some beta-blocking drugs and lignocaine (lidocaine). In addition to careful drug selection, the smallest effective dose should be used and the indication for antiarrhythmic therapy should be periodically reassessed during the course of pregnancy.
Three healthy teenagers were exposed to a single pelvic x-ray irradiation as part of sterilization experiments performed in the Auschwitz concentration camp in 1943. Single and multiple carcinomas of the colon and rectum developed 40 years later in the radiation field. Histologic examination of surgical specimens revealed severe radiation-induced changes in all layers of tumor-adjacent areas. In contrast to previous reports of radiation-induced large bowel cancers, these women had not undergone repeated courses of radiation, had no known co-existing disease that might raise the risk for colonic and rectal malignancies, and had an extremely long and remarkably similar latency period. These cases emphasize the need for long-term surveillance in previously radiated patients. Since thousands of teenagers were subjected to similar sterilization experiments, awareness of this association might help in the early diagnosis of additional cases.
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.
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.
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.
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