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Biomedical subjects

N Laufer

Publications and source records attributed to N Laufer.

At least 55 records · Page 3Linked to original sources
PubMed1996

Characterization of intraperitoneal cytokines and nitrites in women with severe ovarian hyperstimulation syndrome.

OBJECTIVE: To assess the potential involvement of cytokines and nitrites in the hyperpermeability characterizing the ovarian hyperstimulation syndrome (OHSS). DESIGN: A controlled clinical study comparing peritoneal fluid (PF) from patients with severe OHSS and from non-OHSS controls. SETTING: Women hospitalized with severe OHSS in three tertiary medical centers. PATIENTS: Twelve patients with severe OHSS necessitating paracentesis and 20 non-OHSS controls. INTERVENTIONS: The criteria for ultrasound-guided paracentesis were tense ascites, hydrothorax, hemoconcentration, or oliguria. MAIN OUTCOME MEASURES: Interleukin (IL) 1 beta IL-1 receptor agonist, IL-2, IL-6, IL-8, and tumor necrosis factor alpha (TNF alpha) levels in PF were assayed by ELISA; nitrites were measured by the "Griess" reaction. Estradiol and P were determined by RIA. RESULTS: Ovarian hyperstimulation syndrome patients had significantly higher PF IL-6 (3,523 versus 30 pg/mL), TNF alpha (14 versus 4.2 pg/mL), and IL-8 (1,695 versus 900 pg/mL). In the serum, only IL-6 levels were significantly higher (375 versus 11 pg/mL). Conversely, nitrite levels were significantly lower in PF of OHSS patients (0.5 versus 34 nmol/mL). Interleukin 1 levels were higher and IL-1 receptor antagonist levels were lower in OHSS patients, suggesting potentially increased biologic potency of IL-1. CONCLUSION: These findings suggest that these substances could be involved in mediating the capillary hyperpermeability characterizing this syndrome.

Ascitic Fluid↗
PubMed1995

Ovulation induction with clomiphene citrate complicated by deep vein thrombosis.

A case of recurrent deep vein thrombosis following standard clomiphene citrate treatment, in a patient with a history of a previous episode of deep vein thrombosis, is described. This case indicates that deep vein thrombosis might be a rare but hazardous complication of clomiphene citrate treatment in patients with certain risk factors. We recommend that the use of clomiphene citrate in such cases be undertaken with caution and under close surveillance.

Adult↗
PubMed1995

Reduction of an incisional hernia using the open laparoscopic technique.

Recently published cases of operative laparoscopy complicated by incisional hernia reemphasizes the potential hazard of the procedure. A new approach may be an alternative to traditional laparotomy for reducing small bowel herniation through the 12-mm cannula incision. Explorative laparoscopy by the open technique was performed and a loop of small bowel was reduced using an atraumatic grasping forceps. We find this approach safe and convenient.

Abdominal Muscles↗
PubMed1995

Insulin resistant and non-resistant polycystic ovary syndrome represent two clinical and endocrinological subgroups.

We studied the clinical and endocrine features of 35 patients with polycystic ovary syndrome (PCOS) who are either insulin resistant or non-insulin resistant. The occurrence of insulin resistance was determined by measuring insulin and glucose concentrations following a standard 75 g oral glucose load. All patients were evaluated by anthropometric measurements: body mass index (BMI), percentage of body fat (BCF) and waist-to-hip ratio (W/H), degree of hirsutism (Ferriman-Gallwey method) and endocrine profile. Fourteen patients had insulin resistance of unknown origin whereas four were due to a type A insulin receptor mutation, and 17 were non-insulin resistant. The insulin resistant patients were significantly more obese (higher BMI P < 0.0001, BCF P < 0.002 and W/H ratio P < 0.005) and were more hirsute (P < 0.002) than the non-insulin resistant patients. Testosterone concentrations were significantly higher in the insulin resistant group than in the non-insulin resistant group (2.65 versus 1.37 nmol/l; P < 0.027), whereas sex hormone-binding globulin was lower in insulin resistant patients (30.61 versus 19.48 nmol/l; P < 0.02). Non-insulin resistant patients showed a high luteinizing hormone to follicle stimulating hormone ratio, while a normal ratio was found in the insulin resistant subpopulation (2.94 versus 1.34; P < 0.0001). We concluded that PCOS comprises two subpopulations, one with insulin resistance of different aetiologies and the other which has no insulin resistance. These two groups differ in their anthropometric and endocrine features. The diagnosis of insulin resistance in PCOS can be easily determined by the insulin response to an oral glucose tolerance test.

Adult↗
PubMed1995

Interleukin-1-mediated stimulation of prostaglandin E production is without effect on plasminogen activator activity in human granulosa lutein cell cultures.

In continuation of earlier observations on the involvement of interleukin-1 (IL-1) in ovarian function, we examined the ability of IL-1 to modulate plasminogen activator (PA) activity and prostaglandin (PG) synthesis in human granulosa lutein cells (GLCs). Toward this goal, GLCs were obtained from women undergoing in vitro fertilization, preincubated with 10% fetal calf serum for 48 h, and subsequently cultured for 48 h in serum-free media in the absence or presence of IL-1 beta (10 ng/mL). Cellular PA activity was measured by plasminogen-dependent cleavage of the chromogenic substrate H-D-valyl-L-leucyl-L-lysine-p-nitroanilide (S-2251). Prostaglandin E (PGE) levels were assayed by conventional RIA. Exposure of GLCs to IL-1 resulted in a 50% increase in PGE production, a 33% suppression of PA activity, and a 75% increase in the ability of the corresponding conditioned media to inhibit exogenous urokinase activity. The inhibitory capacity was attributable to an IL-1-mediated increase in PA inhibitor type-1 (PAI-1) production, inasmuch as urokinase inhibition could be abolished by the administration of a polyclonal antihuman PAI-1 immunoglobulin G. IL-1 treatment had no effect on plasmin or trypsin inhibition. Exposure of GLCs to IL-1 receptor antagonist abolished the ability of IL-1 to enhance PA inhibitory activity and PGE production, thereby establishing specific IL-1 receptor-mediated effects. The ability of IL-1 to suppress PA activity and to produce PAI-1 persisted in the presence of indomethacin, a potent inhibitor of PG synthesis. Likewise, transforming growth factor-beta 1 suppressed the ability of IL-1 to stimulate PGE production without affecting the IL-1-induced effects on the PA system. The present findings suggest a pluripotent response of GLCs to IL-1, characterized by the induction of PAI-1 and the suppression of PA occurring concurrent with, but independent of, PG production. These observations support the potential involvement of IL-1 in the regulation of human ovulatory processes.

Amino Acid Sequence↗
PubMed1995

Embryonic cultures but not embryos transplanted to the mouse's brain grow rapidly without immunosuppression.

Embryos and embryocultures can be successfully transplanted into various bodily organs. However immunosuppression or homogenicity are required for the success of such experimental manipulation. Since the brain is considered immunologically privileged, we transplanted 2-4 cell embryos of C57BL x BALB/c, embryonic stem cells (ES) or embryoid bodies (EB) cultures into the hippocampus of the heterogeneous mouse stock HS/IBg. Both ES and EB cultures developed into an extensive growth, eventually larger than the brain itself, causing the death of the host in less than 29 days. The growth was identified as teratoma, mostly made of immature cells and tissues of diverse origin. Thus, the overall histological picture was that of a malignant teratoma. On the other hand, no embryos were found at any time after the transplantation; apparently, they could not survive in the host brain. The growth rate and the relative lack of rejection suggest that the brain offers a unique medium for ES and EB cultures but, not to embryos.

Animals↗
PubMed1995

Cost analysis of in vitro fertilization.

In vitro fertilization (IVF) has become a routine tool in the arsenal of infertility treatments. Assisted reproductive techniques are expensive, as reflected by the current "take home baby" rate of about 15% per cycle, implying the need for repeated attempts until success is achieved. Israel, today is facing a major change in its health care system, including the necessity to define a national package of health care benefits. The issue of infertility and whether its treatment should be part of the "health basket" is in dispute. Therefore an exact cost analysis of IVF is important. Since the cost of an IVF cycle varies dramatically between countries, we sought an exact breakdown of the different components of the costs involved in an IVF cycle and in achieving an IVF child in Israel. The key question is not how much we spend on IVF cycles but what is the cost of a successful outcome, i.e., a healthy child. This study intends to answer this question, and to give the policy makers, at various levels of the health care system, a crucial tool for their decision-making process. The cost analysis includes direct and indirect costs. The direct costs are divided into fixed costs (labor, equipment, maintenance, depreciation, and overhead) and variable costs (laboratory tests, chemicals, disposable supplies, medications, and loss of working days by the couples). The indirect costs are the costs of premature IVF babies, hospitalization of the IVF pregnant women in a high risk unit, and the cost of complications of the procedure. According to our economic analysis, an IVF cycle in Israel costs $2,560, of which fixed costs are about 50%. The cost of a "take home baby" is $19,267, including direct and indirect costs.

Costs and Cost Analysis↗
PubMed1994

Perinatal outcome of triplet pregnancies following assisted reproduction.

PURPOSE: This collaborative work was undertaken to assess perinatal outcome of in vivo conceived triplets to those following in vitro fertilization and assisted reproductive technologies (ART). METHODS: 151 triplets were examined; 56 delivered following ART, 55 following ovulation induction by gonadotropins (GN), 27 following clomiphene citrate (CC), and 13 conceived spontaneously. RESULTS: Mean gestational length of triplets following ART (33.2 wks) was not different from those conceived following GN (33.4 wks) or CC (34.2 wks), but was significantly shorter compared to triplets following spontaneous conception (35.3 wks). Mean fetal birthweight following ART (1743 g) did not differ significantly from that following GN (1683 g) or CC (1863 g) but was significantly lower compared to those delivered after spontaneous conception (1963 g). Although no difference was found in the incidence of low birthweight infants between the groups studied, the incidence of very low birthweight newborns (<1500 g) following ART or GN was significantly higher than following spontaneous conceptions (30.6%, 30.3% vs 10.3%). Differences in perinatal mortality were not significantly different between the groups examined (77.9, 60.6, 111.0, 25.6/1000 for ART, GN, CC, and spontaneous conceptions respectively). CONCLUSION: In conclusion, a similar perinatal outcome was shown for triplets conceived following ART and those following ovulation induction by GN, suggesting that the in vitro conditions as such were not the main contributing factor influencing the clinical outcome but rather the GN treatment. Triplets conceived spontaneously have a better outcome compared to those following ovulation induction or ART in terms of gestational length and birthweight.

Birth Weight↗
PubMed1994

The effect of estradiol depletion during the luteal phase on endometrial development.

OBJECTIVE: To examine whether luteal E2 is obligatory for obtaining an adequately developed endometrium. DESIGN: Survey of women with premature ovarian failure (POF) in a prospective, controlled, randomized study. SETTING: In vitro fertilization unit in a tertiary care university medical center. PATIENTS: Fourteen amenorrheic women with POF, candidates for oocyte donation, were divided into two distinct groups with seven women in each subgroup. INTERVENTIONS: Endometrial priming with a fixed dose of oral micronized E2, 4 mg/d for 14 days, was similarly performed in the study and the control groups. Progesterone replacement during the luteal phase was also identical in the two groups and was accomplished by IM P in oil, 50 mg/d for another 14 days. Only the control group continued to have the same E2 regimen during the luteal phase. MAIN OUTCOME MEASURES AND RESULTS: Follicular phase mean E2 levels as well as luteal phase mean P levels were similar in both groups. However, luteal E2 levels differed significantly between the study and the control groups (21 +/- 5 and 692 +/- 199 pg/mL, respectively; conversion factor to SI units, 3.671). Nevertheless, histologic evaluation of endometrial biopsies on days 21 and 26 were similar for both groups. Endometrial gland dating, using light microscopy in the study and the control groups, on day 21, was 19.1 +/- 0.8 and 18.4 +/- 0.5, respectively, and on day 26, 25.4 +/- 0.8 and 25.9 +/- 0.5, respectively. Dating of the stroma in the two biopsies was also similar in both groups. Moreover, transmission electron microscopy performed in two patients of the study group showed typical characteristics of a secretory endometrium. CONCLUSIONS: Luteal E2 depletion in the human does not seem to adversely affect the morphological developmental capacity of the endometrium. Our results suggest that E2 secretion by the corpus luteum in the human does not appear to be obligatory for the development of a normal secretory endometrium. The actual receptivity of the endometrium after such preparation needs to be evaluated.

Adult↗
PubMed1994

The effect of progesterone administration in the follicular phase of an artificial cycle on endometrial morphology: a model of premature luteinization.

OBJECTIVE: To evaluate the effect of premature P administration on artificially prepared endometrium in women with ovarian failure. DESIGN: To mimic premature luteinization, patients with ovarian failure were treated with continuous estrogen and episodic P during the follicular phase of artificial cycles. SETTING: In vitro fertilization unit at a university hospital. PATIENTS: The study group included 16 patients with ovarian failure who were randomly divided into two groups. Group A (8 patients) was treated by episodic P administration during the artificial follicular phase on days 2 and 7 (12.5 mg of P in oil IM), and in group B (8 patients), P (6.25 mg) was added on days 3, 4, and 5. Another 16 patients (group C), age matched to the study group, were arbitrarily allocated to serve as controls and had standard preparatory cycles without P supplementation in the follicular phase. Serum E2 and P levels and endometrial biopsies were taken on days 14 and 26. RESULTS: Serum E2 levels were comparable between the study group (group A+B) and controls on both days 14 and 26. Although serum P levels did not differ between the groups on day 26, it was higher in the follicular phase of the study group than in the controls (1.9 +/- 4.0 and 0.2 +/- 0.1 ng/mL, respectively). In the study group, 8 of 16 patients demonstrated early secretory changes in the late follicular phase biopsies, and 9 of 16 women developed stromal-glandular discrepancy in the late luteal phase. This differed significantly from the controls in which only one late luteal biopsy was out of phase. CONCLUSIONS: Episodic surges of P during the follicular phase may result in impaired endometrial development that cannot be corrected by P supplementation during the luteal phase. This unique model provides evidence for the potential detrimental effect of premature P secretion in the follicular phase on endometrial function.

Adult↗
PubMed1994

The use of vaginal tablets as a vehicle for steroid replacement in a donor oocyte program.

Nine women enrolled in the donor egg program received in a preparatory cycle 6 mg of E2 by vaginal tablets two times per day for the first 14 days, followed by a combined preparation of 6 mg of E2 and 50 mg of P as vaginal tablets, two times per day for another 14 days. Adequate serum levels of E2 and P and favorable sonographic endometrial thickness were achieved throughout the cycle in all patients. Eight endometrial biopsies taken on days 25 to 26 were independently assessed as being representative of day 25 +/- 2. One endometrial biopsy was out of phase. It is concluded that vaginal tablets of E2, followed by a combined preparation of vaginal tablets of E2 and P, is an effective method for establishing an appropriately developed endometrium in a donor oocyte program. Endometrial preparation in donor oocyte programs can be simplified by the use of these tablets.

Biopsy↗
PubMed1994

A comparison between a standard and reduced dose of D-Trp-6-luteinizing hormone-releasing hormone administered after pituitary suppression for in-vitro fertilization.

A randomized prospective study was undertaken to compare low and standard luteinizing hormone-releasing hormone agonist (LHRHa) dosage used in combination with gonadotrophins in ovarian stimulation for in-vitro fertilization (IVF). A total of 42 ovulatory patients with mechanical infertility were administered 0.5 mg/day LHRHa (Decapeptyl) from day 21 of their cycles for 14 days. Following down-regulation, patients were randomly allocated to continue with the same dose of LHRHa (22 patients, group A) or to receive a lower dose of 0.1 mg/day LHRHa (20 patients, group B) during folliculogenesis. Luteal phase was supported by daily i.m. progesterone (50 mg) injections and human chorionic gonadotrophin (HCG; 1500 IU) every 4 days. Ovarian response, human menopausal gonadotrophin (HMG) dosage used for induction of ovulation, evidence of premature luteinization, and clinical and laboratory IVF outcome, were compared between groups A and B. The two groups were comparable in respect of: age (32.6 +/- 0.7 and 33.0 +/- 0.9 years), HMG dosage (33.0 +/- 1.6 and 36.0 +/- 2.5 ampoules), day of HCG (11.2 +/- 0.3 and 12.2 +/- 0.4), oocytes/patient (13.3 +/- 1.0 and 12.9 +/- 1.3), fertilization rate (68.5 and 65.2%), cleavage rate (95% for both), pregnancy/embryo transfer (32 and 35%) and implantation rate (10.8 and 10.5%), for groups A and B respectively. There was no evidence of premature luteinization or luteolysis in either group. It was concluded that lowering the dose of LHRHa to 0.1 mg/day during folliculogenesis had no adverse effect on ovarian response or clinical results. However, it had no advantage in reducing the HMG dose used for ovulation induction.

Adult↗
PubMed1994

Preimplantation diagnosis of cystic fibrosis by simultaneous detection of the W1282X and delta F508 mutations.

W1282X (W) and delta F508 (delta) are the two most common mutations of the cystic fibrosis Israeli population. Patients who are homozygotes (WW and delta delta) as well as compound heterozygotes (W delta) present a severe phenotype of the disease. In the present study, we have developed a polymerase chain reaction (PCR)-based method for the detection of both mutations simultaneously in a single blastomere. Unfertilized human oocytes and single polyspermic blastomeres were subjected to a two-round PCR amplification: a first round of multiplex PCR followed by a second round of nested PCR, done separately at each locus. Clear signals at both loci were obtained in 51% (47/65) of oocytes and 69% (24/35) of blastomeres. The genotype of the single cell analysed was determined by endonuclease digestion of the W products and by heteroduplex formation of the delta F products. This diagnostic system will allow the identification of affected embryos (WW, delta delta, W delta) as well as phenotypically normal carriers (W+, +delta), and therefore may be used for cystic fibrosis preimplantation diagnosis in families who carry either or both mutations.

Base Sequence↗
PubMed1994

Hyaluronic acid for preventing experimental postoperative intraperitoneal adhesions.

Adhesions, which form in > 60% of patients following major abdominopelvic surgery, are a common cause of morbidity and infertility in women. Hyaluronic acid is a naturally occurring polysaccharide that has been shown to be beneficial in ophthalmic surgery and as intraarticular injections. This study was designed to examine the use of hyaluronic acid as an agent for adhesion prevention after experimental abrasion of rat uterine horns and to explore its possible mechanism of action. Twenty-nine female Sabra rats were randomly assigned to either a saline (n = 13) or hyaluronic acid (n = 16) group. Adhesions were created by local abrasion of the uterine surfaces. Five milliliters of 1% hyaluronic acid or saline was instilled intraperitoneally. Three weeks later the animals were killed and subjected to a second laparotomy. Intraabdominal adhesions were graded on the basis of gross appearance using a scoring system from 0 to 5. The adhesion score in the animals treated with hyaluronic acid was significantly (P < .001) lower than that in the control animals. Hyaluronic acid did not affect the attachment or proliferation of fibroblasts but had an inhibitory effect on platelet aggregation in a dose-dependent manner. Intraperitoneal instillation of 1% hyaluronic acid significantly minimized adhesions formed experimentally. The mechanism of action may involve inhibition of platelet aggregation.

Animals↗
PubMed1993

Left ventricular rupture following myocardial infarction treated with streptokinase: successful resuscitation in the cardiac catheterization laboratory using pericardiocentesis and autotransfusion.

An 80-year-old female developed left ventricular rupture in the cardiac catheterization laboratory following myocardial infarction treated with streptokinase. The patient was resuscitated using pericardiocentesis and autotransfusion. This technique and the predisposing factors for left ventricular rupture are discussed.

Aged↗