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J Ovadia

Publications and source records attributed to J Ovadia.

At least 91 records · Page 5Linked to original sources
PubMed1991

Thiol status in human sperm.

The passage of spermatozoa along the epididymis is characterized by a gradual stabilization of intracellular organelles mainly through the oxidation of thiol groups. In this study, we examined the relationship between the thiol-disulfide status of human spermatozoa (using a specific fluorescent probe, monobromobimane) and routine semen analysis parameters. Fluorescence intensity was measured by spectrofluorimeter and its frequency distribution within samples, using a fluorescence-activated cell sorter. The mean proportion of reactive thiols SH/(SS + SH) in 29 semen samples was 29.8% +/- 2.5%. When comparing thiol labeling patterns, oligozoospermic samples differed from normozoospermic ones (P less than 0.05). However, within the normozoospermic group, no correlation was found between thiol-labeling patterns and routine sperm parameters or fertilizing capacity in vitro. No difference in thiol labeling patterns was found between "swim-up" and "whole semen" preparations.

Bridged Bicyclo Compounds↗
PubMed1991

An isocentric chair for the simulation and treatment of radiation therapy patients.

There are a variety of clinical situations in which patients undergoing radiation therapy can benefit from being treated in an upright position. The authors describe a new design for a treatment chair to assist in accomplishing this task. The present chair differs from previous designs in that it can be used with existing radiotherapy simulators as well as treatment units and that it permits isocentric setup and treatment of tumors either at the nominal source-to-axis distance (SAD) of a machine or at extended distance. This design permits treatment of mediastinal tumors as well as those of the head and neck using a variety of field arrangements including AP-PA, opposed laterals, and multiple obliques. The seat is designed on the "tool platform" principle. A wide variety of devices can be attached onto it to ensure accurate and reproducible, yet comfortable, patient positioning.

Humans↗
PubMed1991

The relationship between in vitro fertilization and naturally occurring antibodies: evidence for increased production of antiphospholipid autoantibodies.

OBJECTIVE: Assessment of possible effects of ovarian stimulation during in vitro fertilization (IVF) treatment cycles on circulating levels of antiphospholipid and antinuclear autoantibodies. DESIGN: The study was performed prospectively. Sera were obtained at three time points along IVF treatment cycle. Levels of autoantibodies directed against nuclear components, mitochondrial antigens, and phospholipids were determined using enzyme-linked immunosorbent assay. PATIENTS: Thirty-five patients, who underwent at least one previous IVF attempt, and 36 age- and sex-matched controls were analyzed. All participants were randomly selected. RESULTS: The mean levels of antiphospholipid (but not antinuclear) autoantibodies in sera from IVF-treated patients were found to be significantly higher than the corresponding values of the control group (for immunoglobulin [Ig]M isotype: anticardiolipin, antiphosphatidyl L-serine; for IgG isotype: anticardiolipin, antiphosphatidyl L-serine, and antiphosphatidylcholine; P less than 0.0001, assessed by Mann-Whitney test). The autoantibody levels remained more or less constant at different time points along the treatment cycle. No correlation with age and number of previous IVF cycles was demonstrated. CONCLUSIONS: Serum levels of antiphospholipid (but not antinuclear) autoantibodies increase after IVF treatment. Based on these preliminary data, it is not yet possible to estimate if the observed changes in autoantibody levels might have any future clinical influence on infertile patients undergoing IVF treatment.

Adult↗
PubMed1991

CD5+ B cells and naturally occurring autoantibodies in cancer patients.

We have determined the percentage of CD5+ B lymphocytes in the peripheral blood of cancer patients and healthy controls, using antibodies directed at the CD5 and CD19 (pan-B) markers. The frequencies of CD5+ B cells, expressed as a percentage of total B cells, ranged from 14.3 to 57.5% in the controls and from 14.8 to 82.8% in the patient population. One-third of the cancer patients had frequencies greater than 2 s.d. above the mean of the control population. The CD5+ B cell fraction expressed as a percentage of total lymphocytes was also significantly elevated in this group of cancer patients. These results suggest that the CD5+ B cell compartment may be affected by the malignant process or by the therapy modality employed. The plasma levels of several naturally occurring autoantibodies, the products of the CD5+ B cells, were also assessed in cancer patients and controls. No significant differences were observed when reactivity to several autoantigens was measured. These included nuclear components and phospholipids.

Adolescent↗
PubMed1991

Gestational diabetes mellitus. A survey of perinatal complications in the 1980s.

Neonatal morbidity was assessed in the offspring of 878 mothers with gestational diabetes mellitus (GDM), 132 mothers with pre-GDM, and 380 control subjects. Compared with the control group, the GDM group had a higher incidence of complications, including macrosomia, hypoglycemia, hyperbilirubinemia, hypocalcemia, polycythemia, and major congenital anomalies (P less than 0.05). Although our GDM patients were stringently managed with diet or diet plus insulin, as indicated, and maintained almost euglycemic values, these neonatal complications could not be eliminated. Our data may be consistent with observations published during the last decade that even subtle degrees of maternal hyperglycemia can have a detrimental effect on perinatal outcome. Most neonatal complications readily respond to therapy if diagnosed and treated early and promptly. Macrosomia can have a detrimental effect on delivery (trauma) and later long-term implications during childhood. Tight metabolic control with diet and, when indicated, insulin treatment may be advantageous in reducing fetal birth weight. Criteria of how tight the metabolic control should be remain to be accurately defined.

Diabetes, Gestational↗
PubMed1991

Effect of sex hormones on human T cell activation by concanavalin A.

The effect of sex hormones on concanavalin A (Con A)-activated human T cells was studied. We show that neither 17 beta-estradiol (E2) nor progesterone, in concentrations of up to 10(-6) M, alters the proliferative response of peripheral-blood mononuclear cells (PBMC) of healthy postmenopausal women. Furthermore, the hormones had no effect on the composition of T cell populations and on the expression of activation markers. We extended our study to a unique T cell population that is characterized by the ability to form rosettes with human erythrocytes, following Con A activation (designated autorosette-forming cells; ARFC) and known to manifest suppressive activity. Indeed, the in vitro addition of E2 (neither progesterone nor testosterone) to Con A-stimulated PBMC brought an about 2- to 4-fold increase in the frequency of ARFC. Tamoxifen, an antiestrogen drug, reduced the frequency of estrogen-stimulated ARFC to the original low level. Furthermore, the inhibitory effect of growth medium from ARFC cultures originally stimulated with Con A + E2 was found to be higher than that of ARFC cultures originally stimulated with Con A alone.

Concanavalin A↗
PubMed1990

Transvaginal sonography in postmenopausal women.

Transvaginal sonography (TVS) is a recent addition to the diagnostic techniques available for the evaluation of the female pelvis. Our experience in over 200 cases of postmenopausal women is the subject of this synoptic review. Using this technique in 60 women, we were able to detect endometrial changes such as endometrial carcinoma or adenomatous hyperplasia in 81% and in a group of 19 patients myometrial invasion in 84%. Fibroids of different sizes and locations could be recognized, some of them with signs of cystic degenerations. In 48 postmenopausal women, TVS was used to follow the morphologic changes in the endometrium stimulated by hormone replacement therapy. Histological features of the endometrium were in close correlation with the sonographic patterns obtained. Ultrasound evaluation has been suggested as a possible screening tool for early changes in ovarian size and morphology. Fifty patients were evaluated for the effectiveness of TVS to detect ovarian pathology. The sensitivity and specificity were 83% and 100%, the same as that of gross examination of the ovary at the time of surgery. It seems that TVS is a reliable tool in the detection of early changes in the postmenopausal ovary, but further evaluation in a large population is necessary to assess the usefulness of TVS as a routine screening tool for early ovarian carcinoma. Twenty-nine postmenopausal women with unilateral simple cysts (diameter less than or equal to 5 cm) were identified. All exhibited benign histopathologic changes. We conclude that small (less than 5 cm) postmenopausal cysts have a low incidence of malignancy and could be followed by TVS without immediate surgical intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Endometrial laser ablation in rabbits: a comparative study of three laser types.

Endometrial laser ablation is one of the alternatives to hysterectomy in cases of intractable uterine bleeding. It is currently performed using the Nd:YAG laser at 1.06 microns. The aim of this study was to compare the tissue effect of three types of laser irradiation (Nd:YAG laser at 1.06 and 1.32 microns and holmium laser at 2.12 microns) on the rabbit endometrium. Crater formation, coagulation necrosis, and muscle necrosis were evaluated at the time of ablation, as well as at 1 week and 4 weeks postablation. The results were assessed by determining the depth and width of the affected portion in the uterine wall (lumen to serosa). It was shown that Nd:YAG laser at 1.32 microns caused more generalized and extended effects as compared with the other laser types examined. Endometrial regeneration was faster after ablation by the Nd:YAG laser at 1.06 microns and the holmium laser than by the Nd:YAG laser at 1.32 microns. The widest range of "ablation energy" (defined as that causing ablation without muscle damage) was achieved by applying the holmium laser. Further evaluation of the holmium laser for this indication is recommended.

Animals↗
PubMed1990

Congenital hereditary hypothyroidism--prenatal diagnosis and treatment.

Intrauterine diagnosis of congenital hypothyroidism was established on the basis of TSH concentration in amniotic fluid in the 22nd week of gestation for the offspring of a couple both known to have an iodide organification defect. Prenatal treatment consisted of intramniotic injections of 500 mcg Na-1-thyroxine, which was administered from the first amniocentesis until one week before delivery. Following delivery, the diagnosis was confirmed by the elevated level of TSH, 60.5 uU/ml, and a gradual decrease of fT4 to 0.8 ng/ml. Regular substitution therapy was commenced on the third day of life. The normal shape and location of the thyroid gland was demonstrated by Technetium scintiscan. At 18 months the infant revealed no significant deviation from normalcy in growth or mental capacity. This experience indicates that testing of amniotic fluid for TSH in the 22nd week of gestation can be diagnostic for congenital primary hypothyroidism. Furthermore, it is suggested that the treatment approach described is warranted in all cases in which there is a high risk of congenital primary hypothyroidism.

Amniotic Fluid↗
PubMed1990

Surgery in postmenopausal women--the value of transvaginal sonography.

Transvaginal sonography is a recent addition to the diagnostic techniques available for the evaluation of the female pelvis. Transvaginal sonography is performed with a high-frequency transducer placed in the vagina where it is in close anatomic proximity to the pelvic structures. The procedure overcomes difficulties in imaging obese patients, those with a large amount of bowel gas, and those with inadequate bladder filling. Our experience in over 200 cases of postmenopausal women is the subject of this review. This technique has been employed to detect ovarian and adnexal abnormalities, endometrial changes (hyperplasia and endometrial carcinoma), myometrial invasion, fibroids, adnexal torsion and free fluid in the rectouterine fossa. The results suggest that transvaginal sonography has considerable advantages in the evaluation of pelvic structures in postmenopausal women prior to planned surgical exploration.

Adnexal Diseases↗
PubMed1990

The relationship between sperm parameters and fertilizing capacity in vitro: a predictive role for swim-up migration.

The relationship between sperm parameters and fertilizing capacity in vitro was examined retrospectively, with the aim of finding predictive criteria for successful in vitro fertilization. Three hundred thirty semen samples were used to inseminate 1462 oocytes. Conventional parameters of sperm concentration and percentage motility in the ejaculate as well as swim-up migration were analyzed in relation to fertilization rate. It was shown that the probability of fertilizing human oocytes in vitro decreases significantly when (a) the sperm concentration is below 20 x 10(6) spermatozoa/ml ejaculate (P = 0.006), (b) motility is lower than 80% (P = 0.002), or (c) less than 4 x 10(6) motile spermatozoa/ml are concentrated in the swim-up fraction (P less than 0.0001). It was also demonstrated that nonfertilizing sperm could not be distinguished from fertilizing sperm by the conventional criteria but rather by the average concentration of motile spermatozoa in the swim-up fraction [12.5 +/- 1.5 and 22.3 +/- 2.3 x 10(6)/ml for the 0 and the 100% fertilization groups, respectively (mean +/- SE; P less than 0.01)]. Thus, the swim-up migration technique can serve as a predictive test for the in vitro fertilizing capacity of sperm.

Fertilization in Vitro↗
PubMed1990

Physicochemical properties of follicular fluid and their relation to in vitro fertilization (IVF) outcome.

Despite the limited data that are available concerning FF physicochemical properties, the following conclusions can be drawn. (1) FF temperature is lower than ovarian stroma and body temperatures. The physiological significance of this gradient is unknown. (2) Follicular size increases exponentially prior to ovulation. The relationship between FF volume and successful IVF outcome is well established. (3) A highly significant association exists between fertilization (but not embryo cleavage) and FF spectrophotometric absorbance at delta optic density of 455 nm. (4) FF behaves as a non-Newtonian fluid--its viscosity changes at different shear rates. Neither FF viscosity nor its refractive index was found to correlate with the presence of oocytes, their maturation grade, or their fertilizing capacity. (5) FF osmolarity is similar to that of the plasma. There is no information linking variations in FF osmolarity to IVF outcome. (6) FF pH is acidic, probably due to acid mucopolysaccharides. It appears that the intact follicle is capable of buffering any carbon dioxide which diffuses through its wall at the time of intraperitoneal insufflation. The transvaginal aspiration technique eliminates any possible effect of exogenous gas on FF pH. (7) Regarding the intact follicle, it was shown that (a) there is a small potential difference across the follicle wall, and (b) intrafollicular pressure remains steady prior to ovulation. This information may shed some light on mechanisms underlying FF formation and ovulation. No experiments relating these properties to IVF outcome have been performed.

Animals↗