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Biomedical subjects

R Rabinowitz

Publications and source records attributed to R Rabinowitz.

At least 127 records · Page 7Linked to original sources
PubMed1987

Follicular fluid contents as predictors of success of in-vitro fertilization-embryo transfer.

In order to establish criteria for selection of the best ova in in-vitro fertilization-embryo transfer (IVF-ET) programes we have examined the follicular fluid (FF) levels of plasminogen activator (PA), collagenolytic activity, progesterone (P) and alpha 2 macroglobulin (alpha 2M) and related them to the success of pregnancy. PA activity was similar in FF of pregnant and nonpregnant cycles, 13.8 +/- 3.9 mU/ml versus 14.6 +/- 2.9 (mean +/- SEM) respectively. By contrast, FF from pregnant cycles exhibited lower collagenolytic activity (49.6 +/- 3.9% versus 67.9 +/- 3.0; P less than 0.001). Likewise, in a semi-quantitative assay of alpha 2M, only 18.4% of the aspirates from pregnant cycles showed a precipitation line, whereas 76.8% of those from non-pregnant cycles were positive. Levels of P in aspirates from pregnant cycles were in the intermediate range, as compared with those from non-pregnant cycles (0.06-5.5 micrograms/ml versus 0.02-12.0 micrograms/ml). All these assays can be completed before ET and performed in IVF-ET programmes. In conclusion, it seems that a combination of follicular alpha 2M levels and collagenolytic activity, and to a lesser extent addition of P assay, may serve as good criteria for selecting the best embryos for establishment of pregnancy.

Cleavage Stage, Ovum↗
PubMed1986

Glucocorticoids increase the fluidity of the fetal-rat liver microsomal membrane in the perinatal period.

Dexamethasone, a synthetic glucocorticoid, was administered to pregnant rats during the last week of pregnancy in order to examine its effects on the fluidity of the developing fetal-rat liver microsomal membrane. This early prenatal exposure to dexamethasone, which preceded the natural appearance of fetal corticosteroids, markedly accelerated the normal perinatal course of fluidization of this membrane. The lipid apparent microviscosity, which was determined by measurement of fluorescence polarization, decreased in 21-days-old treated fetuses to values that were indistinguishable from those of untreated newborn rats. This dexamethasone-mediated acceleration of membrane fluidization was associated with an increase in the index of unsaturation of the fatty acyl moiety of microsomal lipids. Dexamethasone caused a significant increase in the microsomal content of polyunsaturated fatty acids (arachidonic and linoleic acid), which was accompanied by a decrease in content of monoenoic fatty acids (oleic and palmitoleic acid). This early exposure in utero to dexamethasone precociously induced the changes in fatty acid composition of fetal-rat liver microsomal lipids that normally occur between the last day of pregnancy and the first day of extra-uterine life. These results suggest that endogenous glucocorticoids play a major role in the perinatal fluidization of the rat liver microsomal membrane.

Animals↗
PubMed1986

Artificially induced endometrial cycles and establishment of pregnancies in the absence of ovaries.

In eight women with ovarian failure, we induced histologically normal endometrial function during a preparatory cycle consisting of sequential administration of estrogen and progesterone. During a subsequent cycle, endometrial stimulation was synchronized with surrogate-embryo transfer performed on days 16 to 21. Among the eight women, two pregnancies were established by embryo transfer on days 18 and 19. In both women, ovarian tissue was absent, and these patients therefore serve as an in vivo model for the isolated effects of estrogen and progesterone on implantation and maintenance of pregnancy. Treatment with exogenous estrogen was mandatory up to the 11th week of gestation, and treatment with progesterone until the 18th to 22nd weeks. We conclude that it is biologically feasible to simulate the essential hormonal and endometrial milieu of a fertile menstrual cycle and early gestation solely by the administration of estrogen and progesterone. Days 18 to 19 of the cycle are recommended for successful embryo implantation with this treatment program.

Adult↗
PubMed1986

Qa alloantigen expression on functional T lymphocytes from spleen and thymus.

The cell-surface expression of the class I alloantigen Qa-2 was analyzed on resting and activated spleen and thymus cells using cytotoxic elimination and immunofluorescence and flow cytometry. Spleen cells activated by mitogens or alloantigen were homogeneously positive for cell surface Qa-2, but activated splenic T cells expressed only about one-third as much Qa-2 per cell as did nonstimulated T cells. These data correlated with the ability to perform cytotoxic elimination with Qa-2-specific monoclonal antibodies (mAbs) in that cytotoxic T lymphocyte (CTL) activity was completely abrogated by pretreatment of spleen cells prior to in vitro culture but was only partially eliminated by treatment of CTL effectors. Qa-2-positive cells constituted only a small subpopulation of fresh normal thymocytes, but were enriched (greater than 40% positive) among cortisone-resistant thymocytes (CRT). These Qa-2-positive CRT contained mature thymocytes as defined by Ly phenotype Ly-2-, Ly-1hi. When normal thymocytes were treated with Qa-2-specific mAb and complement prior to in vitro sensitization for generation of allogeneic CTL, CTL activity was completely abrogated despite the fact that the fraction of cells eliminated were undetectable as assessed by cell recovery. CTL effectors from alloantigen-stimulated thymocytes were also susceptible to cytotoxic elimination with Qa-2-specific mAb. These data suggest that the Qa-2 molecule may serve not only as a marker on resting and activated peripheral T cells, but also as a unique marker for functionally mature T cells in the thymus.

Animals↗
PubMed1986

Ultrasonically guided oocyte recovery for in vitro fertilization: an improved method.

Ultrasonically guided follicular aspiration is now routinely used for in vitro fertilization (IVF) in many centers. We present an improved method for oocyte recovery. One hundred nine consecutive patients with mechanical infertility submitted for IVF were included in the study. Superovulation was induced with human menopausal gonadotropin (hMG)/human chorionic gonadotropin (hCG). Oocyte recovery was ultrasonically guided, the bladder filled with phosphate-buffered saline (PBS), and a cannula with trocar used for single percutaneous puncture. The aspiration needle was of 1.6 mm in internal diameter. When compared to published data using smaller-bore needles, it seems that this improved needle increased the number of oocytes recovered to a mean of 6.5 and the number of embryos replaced to a mean of 3.9 per patient, with a pregnancy rate of 20% per transfer.

Embryo Transfer↗
PubMed1986

Fetal response to vibratory acoustic stimulation in periods of low heart rate reactivity and low activity.

The fetal response to vibratory acoustic stimulation during periods of low fetal activity and low fetal heart rate reactivity was studied in 10 healthy pregnant women at term. In each case, two periods of low reactivity were studied. Consecutive cases alternated: The vibratory acoustic stimulus was applied 10 minutes after the first nonreactive period in half of the cases; the remainder were stimulated during the second nonreactive period. The unstimulated period served as a control. After vibratory acoustic stimulation the baseline fetal heart rate, the mean number of fetal heart rate accelerations, and, the number of fetal movements were significantly increased with values in the control nonstimulated periods (p less than 0.0001). This consistent response to vibratory acoustic stimulation may prove to be clinically useful in altering periods of low reactivity observed during nonstress testing of normal fetuses.

Acoustic Stimulation↗
PubMed1986

Correlation between the zona-free hamster egg sperm penetration assay and human in vitro fertilization.

The association between in vitro fertilization (IVF) and the zona-free hamster egg sperm penetration assay (SPA) was studied in 134 couples. The indications for IVF were tubal disease in 82 couples, unexplained infertility in 23, male infertility in 10, and combined mechanical and male factors in 19. In general, a positive SPA was a good predictor of subsequent IVF (91 of 107 couples). Specificity (number of couples with fertilization in vitro divided by the number of couples with a positive SPA times 100) was 94% for tubal infertility, 76% for unexplained infertility, and 46% for male infertility. A negative SPA predicted an overall fertilization failure of 78% (21 of 27 couples). Sensitivity of the test (number of couples with IVF failure divided by the number of couples with a negative SPA times 100) was 100% for tubal and unexplained infertility but only 63% for male infertility. The high predictive value of the SPA for subsequent IVF outcome in tubal infertility and unexplained infertility warrants its routine use for prescreening in IVF programs. Because of the lack of association between SPA and IVF in oligoasthenospermia, the bioassay should not be relied upon for predicting IVF outcome in male subfertility. The overall high association between the animal model and human IVF reinforces the use of the SPA for both basic research and clinical decision-making.

Animals↗
PubMed1986

The value of ultrasonographic endometrial measurement in the prediction of pregnancy following in vitro fertilization.

This work was undertaken for evaluation of the value of endometrial thickness as an early predictor for the success of in vitro fertilization (IVF). Endometrial changes were evaluated ultrasonographically in 47 women undergoing IVF. A high-dose gonadotropin protocol was used for induction of multiple follicular development. Thirty-seven women did not conceive following the procedure (group I), and 10 conceived (group II). Ultrasonographic endometrial measurements were performed repeatedly throughout the cycle. Serum 17 beta-estradiol and progesterone levels were evaluated concomitantly. Three consecutive growth patterns of the endometrium were observed. The first was a rapid one with a daily growth rate of about 0.5 mm from approximately 9 mm on day -3 to 12 mm on day +2 (day 0 being the day of human chorionic gonadotropin administration). The second phase, following follicular aspiration, showed a decrease in growth rate to about 0.1 mm per day until day +11, when a thickness of about 13 mm was measured. In group I growth was arrested from day +11 until menstruation, whereas in group II an accelerated growth rate of about 0.4 mm per day could be demonstrated from day +14 onward. Endometrial growth did not correlate with serum estradiol or progesterone levels. No conception occurred with an endometrial thickness below 13 mm on day +11. It is concluded that endometrial thickness follows a distinct pattern of growth in human menopausal gonadotropin-induced cycles and does not correlate with serum sex hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Ultrasonically guided oocyte collection under local anesthesia: the first choice method for in vitro fertilization--a comparative study with laparoscopy.

Ultrasonically guided oocyte collection gradually replaces laparoscopy in many in vitro fertilization (IVF) centers. In the present study we compare the efficacy of both methods in our IVF program. One hundred twenty patients were prospectively randomized into two groups. Sixty women underwent oocyte collection during laparoscopy under general anesthesia, and 60 women under ultrasound guidance with local anesthesia. Superovulation was induced with human menopausal gonadotropin/human chorionic gonadotropin. For the oocyte collection a cannula with a trocar was used for single percutaneous puncture, through which both ovaries could be reached by the aspiration needle. The number of aspirated oocytes and transferred embryos was higher in the laparoscopy group as compared with the ultrasound group (5.3 versus 4.0 per woman and 3.0 versus 2.3 per woman, respectively); but the clinical pregnancy rate per cycle was similar in both groups (12.5% versus 14.5%). Ultrasound aspiration seems to be as effective as laparoscopy in terms of oocyte retrieval and conception rates. Because the procedure is simple and inexpensive, we believe that it may replace laparoscopy as a method for oocyte collection in most patients who undergo IVF.

Adult↗
PubMed1986

Dismembered nonstented ureteroureterostomy using the carbon dioxide laser in the rabbit: comparison with suture anastomosis.

End-to-end laser welding of transected nonspatulated ureters was compared to conventional spatulated suture anastomosis in 3 kg. rabbits. Nonspatulated sutureless ureteral welding was achieved in 12 rabbits with low energy levels from a carbon dioxide laser. In 12 other rabbits spatulated end-to-end anastomoses were performed with interrupted 7-zero chromic catgut sutures. Patency rate in the welded ureters was 92 per cent, compared to 83 per cent for the suture anastomoses. Histological changes in welded ureters were similar to the sutured ureters. Ureteral welding is achieved in far less time than suture anastomosis.

Animals↗
PubMed1986

Testicular abscess: diagnosis by ultrasonography.

We reviewed 8 cases of surgically proved testicular abscess with emphasis upon the ultrasonographic findings. The images were correlated with testicular anatomy and the pathological findings of abscess formation. In 3 of 8 patients undergoing serial high resolution ultrasound examinations a consistent pattern of testicular abscess was present 1 to 7 weeks preoperatively. In the remaining 5 patients preoperative ultrasound documented the presence of abscess. Recognition of the ultrasonographic appearance of testicular abscess should permit expedient surgical intervention.

Abscess↗
PubMed1986

A new autoreactive monoclonal antibody specific for the Thy-1 antigen.

The present study describes the development of a new IgM monoclonal autoantibody reactive with the Thy-1 antigen. The C16-31 monoclonal antibody (mAb) was considered as autoreactive because it reacted with thymus cells of both the C3H and BALB/c strains, which were involved in the development of the antibody. The antibody was reactive with thymus cells in both immunofluorescent and cytotoxic tests. It also showed a weak immunofluorescent reactivity with peripheral T-lymphocytes. The identification of the specificity detected by the C16-31 mAb as the Thy-1 antigen was based on the following criteria: C16-31 mAB displayed a preferential reactivity with Thy-1.2 bearing thymus cells, rather than with Thy-1.1 bearing thymus cells. The tissue distribution of the antigen detected by the C16-31 antibody by direct tests and by direct tests and by adsorption experiments was in accordance with that characteristic for Thy-1. It was high on brain tissue and on thymus cells, and considerably lower on peripheral T-lymphocytes. Coating of thymocytes with C16-31 antibody blocked their reactivity with other monoclonal Thy-1 antibodies. Conversely, coating of thymus cells with rabbit anti-brain serum (RABR) inhibited the binding of C16-31. The C16-31 mAb differed from the Thy-1 autoantibodies described previously in its relatively strong reactivity with brain tissue and its considerably weaker reactivity with peripheral T-lymphocytes. Moreover, C16-31 mAb showed a preferential allospecificity for Thy-1.2, only in its reactivity with thymocytes. In contrast, it reacted equally well with brain tissue from either Thy-1.2 or Thy-1.1 mice.

Animals↗
PubMed1986

Anti-idiotype to monoclonal anti-swine SLA antibody detects a common idiotype shared by mouse anti-SLA sera and elicits an anti-SLA activity.

Heterologous anti-idiotypic reagents have been prepared against a BALB/c anti-swine MHC (SLAd) monoclonal antibody (74-11-10) in order to test for possible interspecies idiotypic cross-reactions of anti-MHC antibodies. Using these reagents to examine xenoantisera produced in BALB/c mice immunized with swine SLAdd peripheral blood lymphocytes, all animals tested were found to express detectable levels of the 74-11-10 idiotype (Id). The Id could also be detected in one out of five BALB/c mice immunized with swine SLAcc PBL. Swine anti-SLAdd alloantibodies were also tested, but failed to show detectable levels of the 74-11-10 Id. The in vivo administration of anti-idiotypic reagents to BALB/c mice induced detectable levels of 74-11-10 Id positive antibodies that bound specifically to SLAdd PBL. Similar treatment of SLAgg swine (recombinant swine expressing the class I MHC molecules of c) with anti-idiotypic antibodies failed to induce anti-SLAd antibody activity. These results thus indicate that 74-11-10 represents a shared idiotype of BALB/c anti-SLAdd antibodies. The presence of 74-11-10 Id in one mouse immunized with SLAcc PBL suggests that the failure of pigs to express the 74-11-10 Id following treatment with anti-idiotypic antibodies may be the result of tolerance rather than absence of the relevant variable region gene(s).

Animals↗
PubMed1985

Evidence for a regulatory idiotypic network in the in vivo response to H-2 antigens.

Treatment of BALB/c mice with purified pig antiidiotype to 11-4.1 (anti-H-2Kk) monoclonal antibody has been found previously to induce the appearance of idiotype-bearing molecules (Id') in the serum of these mice, in the absence of detectable antigen-binding activity. In the present study we examined the effect of subsequent immunization of such antiidiotype-primed mice with the original H-2Kk antigen. Skin grafting of virgin BALB/c mice with BALB.K skin did not generate any detectable Id' antibodies when tested by enzyme-linked immunosorbent assay (ELISA). In contrast, grafting of antiidiotype-primed mice with BALB.K skin specifically boosted ther serum level of Id' molecules. Challenge of antiidiotype-primed mice with either B10.D2 or rat skin had no effect on the production of such Id' molecules. Absorption studies demonstrated that the majority of Id' molecules induced by H-2Kk antigenic stimulus and detected in ELISA are antigen-nonbinding molecules, thus indicating specific restimulation by the original H-2Kk antigen of nonbinding idiotype-positive B cell clones. The relevance of these findings to the existence of network interactions in the immune response to H-2 antigens is discussed.

Animals↗
PubMed1985

Comparative study of ultrasonically guided percutaneous aspiration with local anesthesia and laparoscopic aspiration of follicles in an in vitro fertilization program.

Twenty patients from our in vitro fertilization program were randomly divided into two groups. Ten women underwent follicular aspiration during laparoscopy while they were under general anesthesia and 10 women had an ultrasonically guided follicular aspiration with local anesthesia. All patients had mechanical infertility, and ovulation was induced with human menopausal gonadotropins. In both groups the same aspiration system with a needle of 1.4 mm inner diameter and a continuous suction at 120 mm Hg were used. In the laparoscopy group the oocyte recovery rate was 82.5% and the fertilization rate 62.5%, with one twin pregnancy; in the ultrasound group the oocyte recovery rate was 75%, and the fertilization rate 61.9%, with a singleton pregnancy. Implications of these results are discussed.

Adult↗
PubMed1985

Establishment of the Amsalem T-cell line from a patient with acute lymphoblastic leukemia. Expression of E-receptor-associated antigens in cells incapable of forming E-rosettes.

A new T-cell line (Amsalem) was established from the peripheral blood of a patient with pre-T leukemia. Amsalem cells are unique in that they possess antigenic determinants associated with the E-receptor, yet fail to form rosettes with sheep red blood cells (SRBC). Amsalem cells were found to possess morphological and cytochemical features characteristic of T-lymphocytes, and were sensitive to the cytotoxic effect of rabbit antisera specific for T-cell antigens. In immunofluorescent tests with monoclonal antibodies, Amsalem cells showed a strong reactivity with the OKT-11A and A-22 antibodies, specific for the E-receptor. The cells were reactive with OKT-4 and showed a very weak reactivity with OKT-6 and OKT-8. No reactivity was found with the OKT-3, Leu 7, Leu 11, and OKM1 antibodies. Amsalem cells failed to form rosettes with SRBC; however, mouse anti-Amsalem serum inhibited the formation of E-rosettes. It is concluded that the Amsalem cell line is a line of pre-T leukemia cells characterized by a dissociation between its inability to form E-rosettes and the presence of antigenic constituents of the E-receptor.

Antibodies, Monoclonal↗