PubMed Health⌕ Search

Biomedical subjects

J Testart

Publications and source records attributed to J Testart.

At least 91 records · Page 5Linked to original sources
PubMed1992

Treatment of adenocarcinoma of the pancreas with somatostatin and gonadoliberin (luteinizing hormone-releasing hormone). The French Associations for Surgical Research.

Experimental studies have shown a significant inhibition of adenocarcinoma of the pancreas by gonadoliberin (luteinizing hormone-releasing hormone [LH-RH]) and somatostatin. The aim of this prospective randomized study was to compare the potential value of somatostatin (250 micrograms every 8 hours), LH-RH (3.75 mg monthly), or combined, to a control group. One hundred sixty-three patients with adenocarcinoma of the pancreas who did not undergo resection for cure were divided into 4 groups that did not differ in terms of clinical, biologic, or pathologic data. The mean survival times were 6 months in the LH-RH plus somatostatin group, 5.5 months in the LH-RH group, 4.3 months in the control group, and 3.8 months in the somatostatin group. However, the life-table analyses for all randomized patients, and separately according to sex, the lymph node extension, and metastatic spread were not different between groups. Improvement of patient status was observed in 20% of the patients receiving hormone therapy without any difference noted between the treatment regimens. These disappointing results may be explained by the degree of extension of pancreatic carcinoma in the patients studied. The results suggest that different hormone therapy regimens might be considered according to the age and the sex of patients, as well as to the presence or absence of hormone receptors.

Adenocarcinoma↗
PubMed1992

Effects of 1,2-propanediol on the cytoskeletal organization of the mouse oocyte.

The effects of 1,2-propanediol, a cryoprotectant used for the freezing of embryos, were tested on the organization of microtubules and microfilaments in mouse oocytes arrested in metaphase II. At low doses (less than or equal to 1.0 M), 1,2-propanediol induced disorganization of the meiotic spindle but at 1.5 M and higher, it stabilized the spindle. Cytoplasmic asters were observed at all doses tested. An extensive network of free microtubules was observed at 1.0 M and 2.0 M 1,2-propanediol, the former having the stronger disruptive effect on the spindle. Higher doses of 1,2-propanediol (greater than or equal to 1.5 M) caused the oocytes to form cytoplasmic blebs. These blebs lacked detectable cortical microfilaments. In contrast, the microfilament-rich area of the cell cortex overlying the meiotic spindle was not modified.

Actin Cytoskeleton↗
PubMed1992

Effect of pentoxifylline on sperm movement characteristics in normozoospermic and asthenozoospermic specimens.

Preliminary evidence has suggested that the phosphodiesterase inhibitor pentoxifylline augments the fertilizing potential of asthenozoospermic sperm samples, presumably by improving sperm movement. Here, we used computer-assisted sperm movement analysis to compare the effects of pentoxifylline in normozoospermic and asthenozoospermic specimens. The study focused on the following issues: the changes in individual movement characteristics in response to pentoxifylline, the rapidity of the response, the effect of sperm capacitation on the response, the persistence of the response after drug removal and the variability of responses among asthenozoospermic individuals. Data obtained show that (i) pentoxifylline increases the curvilinear velocity, path velocity, straight-line velocity, lateral head displacement, beat cross frequency and sperm hyperactivation in both normozoospermic and asthenozoospermic specimens, (ii) pentoxifylline does not modify the percentage of motile spermatozoa, (iii) the pentoxifylline effect reaches a maximum within 10 min of treatment in fresh semen as well as in capacitated sperm suspensions and persists for at least 2 h after drug removal and (iv) pentoxifylline improves the movement characteristics in most asthenozoospermic individuals. Results are discussed with regard to methods of therapeutic application of pentoxifylline as an enhancer of sperm movement in assisted reproductive technology.

Humans↗
PubMed1992

Relationship between fertilizing ability of frozen human spermatozoa and capacity for heparin binding and nuclear decondensation.

Nuclear decondensation of spermatozoa induced by heparin, reduced glutathione (GSH) or a mixture of heparin and GSH was studied using frozen-thawed human spermatozoa. The percentages of decondensed spermatozoa in controls and after treatment for 60 min with 30 mumol heparin l-1, 5 mmol GSH l-1, or heparin-GSH mixture were 1.5, 22.1, 4.3 and 37.6%, respectively. Most of the decondensed spermatozoa were eliminated by Percoll gradient centrifugation of samples previously treated with heparin or heparin-GSH mixture. However, comparable numbers of motile spermatozoa were recovered in the control and in each treated sample, demonstrating that a major proportion of motile spermatozoa was resistant to heparin (or heparin-GSH) effects on nuclear decondensation of spermatozoa. Fertilization of hamster oocytes was attempted using spermatozoa recovered in the 90% Percoll fraction and resistant to heparin-GSH decondensing mixture. Although insemination used a constant number of motile spermatozoa, fertilization rates were higher after treatments with heparin and GSH alone than in control or heparin-GSH-treated samples. In addition the number of spermatozoa that attached to the oocyte plasma membrane was a sixth or a half for sperm pretreated with heparin-GSH or heparin alone, respectively compared with untreated values. However, there was no evidence for induced acrosomal reaction by heparin and GSH, at least at the concentrations used. Qualitative analyses of heparin-binding sites were performed on untreated spermatozoa recovered in the 90% Percoll fraction by incubating spermatozoa in the presence of heparin covalently linked to albumin and coupled to colloidal gold (5 nm). Among this population of spermatozoa, 40.5% bound heparin-gold and labelling was mainly observed on the sperm head surface (88% of labelled spermatozoa) with (59.5%) or without (28.5%) tail labelling. Only a small proportion (23%) of spermatozoa that attached to the oocyte plasma membrane bound heparin-gold conjugate and only weak labelling was observed on the sperm head. Moreover, the proportion of spermatozoa that bound heparin-gold conjugate decreased (r = -0.77, P less than 0.0001) in relation to increasing concentrations of motile spermatozoa in the sample.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Influence of a gonadotrophin-releasing hormone agonist and gonadotrophins on morphometric characteristics of the population of small ovarian follicles in cynomolgus monkeys (Macaca fascicularis).

Small follicles, less than or equal to 100 microns, in monkey ovaries were divided into four types based on the morphological characteristics of the granulosa cells that surrounded the oocyte: primordial, intermediary, primary and secondary follicles. The proportion of primordial follicles positively correlated, whereas those of intermediary, primary and secondary follicles negatively correlated, with the total number of follicles less than or equal to 100 microns. There was no relationship between the population of nongrowing follicles (primordial and intermediary) and that of early-growing follicles (primary and secondary). Administration of exogenous gonadotrophins did not induce significant changes in the population of small follicles, whereas there was a significant increase in the number of intermediary follicles when gonadotrophins were associated with a gonadotrophin-releasing hormone agonist, buserelin. Buserelin can therefore partly inhibit the initiation of ovarian follicular growth in monkeys.

Animals↗
PubMed1992

[Cholecystectomy by celioscopy. Experience in two Upper Normandy hospital units. Apropos of 178 procedures].

Laparoscopic cholecystectomy (LC) emerges as an effective alternative to classical cholecystectomy, but its safety, benefits and indications still need to be clarified. From September 1989 to March 1991, 178 LC were performed by 8 surgeons in 2 hospitals, on 142 women and 36 men with a mean age of 48.2 years. The gall bladder wall was thin in 160 cases and thick in 18 cases (with 6 cases acute cholecystitis). We observed no deaths, 147 simple procedures with a hospital stay and drug requirement lower than with the usual cholecystectomy via laparotomy. But in 21 cases, the procedure needed a laparotomy, and in 10 cases complications occurred, requiring laparotomy in 6 cases. Our results suggest: a) LC is an improvement in the treatment of uncomplicated gallstones; b) a trained surgeon and extreme caution are required in complicated cholelithiasis; c) classical cholecystectomy is still useful in many circumstances.

Adolescent↗
PubMed1992

[Acute thrombosis of the right renal vein. Two cases with coagulopathies].

We report two cases of renal vein thrombosis, unusual because of acute expression, right renal vein localization, absence of the usual renal or perirenal causes, surgical management and a never before reported etiology. In one case the thrombosis was secondary to primary antiphospholipid syndrome, in the other it was secondary to heparin associated thrombocythemia. In this case surgical management was performed during prostacyclin infusion.

Acute Disease↗
PubMed1991

Progression of oocyte maturation from metaphase I to metaphase II is disturbed by previous immunological interference with cumulus cell function.

The effects of an antibody preparation reacting with preovulatory mouse cumuli oophori (anticumulus Ig) on oocyte maturation in vivo and in vitro were studied. Continuous presence of anticumulus Ig in culture medium did not impair oocyte maturation in vitro. Similarly, no effect on oocyte maturation in vivo was observed when anticumulus Ig was given to females superovulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) at the time of hCG treatment. However, when administered earlier, anticumulus Ig brought about serious disturbances of oocyte meiotic competence, since only immature oocytes were ovulated after anticumulus Ig injection at the time of PMSG treatment and as much as 70% of the ovulated oocytes were immature when the antibody was applied 24 hr later. Previous absorption of anticumulus Ig with isolated cumulus cells removed the inhibitory effect of this preparation on oocyte meiotic competence to the same extent as absorption with whole cumuli oophori, despite the persistence of a strong reactivity of the cumulus cell-absorbed antibody preparations with the cumulus intercellular matrix. The ability of oocytes obtained from antibody-injected animals to mature in vitro was also considerably impaired when the injection was made at the time of PMSG treatment. In all cases the maturation defect concerned the progression of meiosis from metaphase I to metaphase II, while the ability of oocytes to undergo germinal vesicle breakdown (GVBD) was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorption↗
PubMed1991

Relationships between in vitro progesterone production by granulosa-luteal cells and certain characteristics of human stimulated cycles.

OBJECTIVE: To explore the conditions of a suitable luteal phase in human stimulated cycles, progesterone (P) production by cultured granulosa cells from preovulatory follicles was related to preovulatory serum estradiol (E2) and number of oocytes. DESIGN: Progesterone production was measured in the presence or absence of human chorionic gonadotropin (hCG) using radioimmunoassay; data were compared using Student's t-test; correlations used linear regression. SETTING: In vitro fertilization and embryo transfer (IVF-ET) for infertility treatment at hospital Antoine Beclère, Clamart, France; scientific studies at Institut National de la Santé et de la Recherche Médicale, Unit 187, Clamart, France. PATIENTS, PARTICIPANTS: Nineteen women, 33 +/- 4 years old, undergoing IVF-ET for nonovarian causes. MAIN OUTCOME MEASURES: High preovulatory E2 usually correlates with high luteal P level. Atretic follicle has reduced follicular E2 production combined with a loss of responsiveness to gonadotropins. RESULTS: Granulosa-luteal cell P production correlated with E2 level (P less than 0.0002). Six cycles, with 14 oocytes recovered per cycle on average, showed reduced plasma E2 per oocyte (P less than 0.001) combined with reduced responsiveness to hCG by granulosa-luteal cells (P less than 0.02). CONCLUSION: Recovery of numerous oocytes might be associated with follicular atresia and deficient luteal phase.

Adult↗
PubMed1991

Platelet-activating factor-acether is a component of human follicular fluid.

OBJECTIVE: Platelet-activating factor-acether (PAF-acether) presence was investigated in 27 human follicular fluids (FFs). DESIGN: Aggregation of washed rabbit platelets was used to measure PAF-acether. Data were compared using Student's t-test. SETTING: Follicular fluids came from the in vitro fertilization program at Antoine Béclère Hospital, and PAF-acether was assayed at Institut National de la Santé et de la Recherche Médicale, Unités 187 and 200, Clamart, France. PATIENTS, PARTICIPANTS: The study concerned five infertile women 29 to 39 years of age. INTERVENTIONS: Ovaries were stimulated with human menopausal gonadotropin under gonadotropin-releasing hormone agonist (GnRH-a) action. MAIN OUTCOME MEASURES: The height of platelet aggregation was compared between FFs and synthetic PAF-acether. RESULTS: Mean FF concentration of PAF-acether was 1,367 to 3,467 pg/mL among women. Values were higher for patients in a long than in a short GnRH-a protocol (P less than 0.05). However, PAF-acether concentration was not related to fertilization rate. CONCLUSIONS: Platelet-activating factor-acether is possibly involved in oocyte release from the follicle, a process occulted by follicular puncture.

Adult↗
PubMed1991

Effect of a gonadotropin-releasing hormone agonist and gonadotropins on ovarian follicles in cynomolgus monkey: a model for human ovarian hyperstimulation.

STUDY OBJECTIVE: To examine the effect on large follicles (greater than or equal to 2 mm) of human menopausal gonadotropin (hMG) and buserelin acetate, a gonadotropin-releasing hormone agonist in monkeys. DESIGN: Experimental. SETTING: Reproductive research laboratory. ANIMALS: Fourteen cyclic cynomolgus monkeys receiving hMG alone for 8 days or buserelin acetate plus 8 (group 1), 12 (group 2), or 16 (group 3) days of hMG administration always starting from day 1 of the cycle. RESULTS: The different treatments were effective in over-riding the specific ovulatory quota of 1, and more large follicles developed in treatments involving long duration and higher doses of hMG. In buserelin acetate plus hMG treatments, the frequency of dissociated follicles and follicles in late atresia were, respectively, lower and higher than in hMG alone treatment. The numbers of recoverable mature oocytes (germinal vesicle breakdown) were similar to the numbers of such oocytes recovered after hyperstimulation performed for human in vitro fertilization and embryo transfer (IVF-ET). However, the number of mature oocytes enclosed in typically preovulatory follicles was very low because there were numerous dysmature follicles. CONCLUSION: These data suggest a deleterious effect of buserelin acetate plus hMG treatments on the recruitable follicles at the time when treatments start. The implications of these observations in the field of human IVF-ET are discussed.

Animals↗
PubMed1991

Studies on the influence of gonadotrophin levels in the early follicular phase on the ovarian response to stimulation.

The gonadotrophic regulation of folliculogenesis has been extensively investigated but little attention has been paid to the influence of early follicular phase levels of endogenous FSH and the FSH/LH ratio when planning ovulation stimulation therapy for IVF. The influence of these factors was investigated in the three studies reported in this paper. A fixed schedule of ovulation stimulation therapy which employed standard treatment regimens, irrespective of the ovarian response, was used to eliminate variation due to treatment factors. Cycles were pretreated with an oestrogen-progestogen contraceptive pill or a progestogen (norethisterone). It was found that both oestrogen-progestogen and progestogen alone decreased the plasma FSH level, although the FSH/LH ratio was significantly reduced only by oestrogen-progestogens. In clinical IVF studies, oestrogen-progestogen pretreatment was associated with a significant reduction in the preovulatory concentration of oestradiol in plasma and the number of aspirated follicles, compared to norethisterone. The administration of FSH for 2 days following oestrogen-progestogen pretreatment and prior to the fixed schedule of ovulation stimulation normalized ovarian steroidogenesis and follicular development. Early follicular phase supplementation with FSH had no influence on progestogen pretreated cycles. The final experiment investigated the influence of FSH/LH levels in the early follicular phase on the outcome of ovarian stimulation. The preovulatory oestradiol concentration was reduced when baseline FSH/LH levels were low compared with when these values were high. Administration of FSH for 2 days in the early follicular phase improved the preovulatory level of oestradiol when baseline FSH/LH was low but had no effect when baseline FSH/LH levels were high.(ABSTRACT TRUNCATED AT 250 WORDS)

Chorionic Gonadotropin↗
PubMed1991

Contribution of preovulatory-phase small follicles to the ovarian response in stimulated cycles.

The usual criteria for ovulation induction in stimulated cycles take into account the number of follicles greater than 14-16 mm in diameter. We have retrospectively investigated how the presence of small (8-12 mm) follicles at the time of the last scan influences the ovarian response for in-vitro fertilization (IVF). The mean number of small follicles was nearly constant (3.8 to 5.9) and did not correlate with the number of large (greater than 12 mm) follicles in various protocols for ovarian stimulation. In patients stimulated under the influence of a gonadotrophin releasing hormone (GnRH) agonist, the number of small follicles was correlated with the oestradiol (E2) peak level and with the number of recovered oocytes. Our data demonstrate a significant contribution of follicles less than or equal to 12 mm to peripheral E2 levels and oocyte production for IVF.

Cell Count↗