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D Royere

Publications and source records attributed to D Royere.

11 recordsLinked to original sources
PubMed1992

Characterization of human follicle-stimulating hormone binding to human granulosa cells by an immunoenzymological method.

An original, nonradiometric method has been developed for studying the binding parameters of native follicle-stimulating hormone (FSH) to its specific receptors in human ovarian granulosa cells. After binding and washing of the cells, hFSH was desorbed from its receptors and quantitatively measured by a specific enzyme immunoassay (EIA) in which nonspecific binding was estimated in the presence of an excess of equine chorionic gonadotropin (eCG/PMSG), which binds to human FSH receptors but does not interfere in the hFSH EIA. This method makes use of native nonmodified hFSH molecules (in contrast to radiometric methods) and permits direct estimation of the binding parameters (Kd and total number of sites). The Kd of hFSH for its human granulosa receptors measured by this technique (4.8 +/- 0.3 x 10(-10) M) is close to that determined by other methods. However, we found a total number of specific FSH receptors per granulosa cell (1 to 6 x 10(4) higher than that reported by others by Scatchard analysis of competition dose-response curves in radioreceptor assays. The method is also sensitive enough to measure the in vivo occupancy of receptors by endogenous hFSH, which was found to be less than 6% in women undergoing hormonal treatment for in vitro fertilization.

Adult↗
PubMed1991

Does in vitro capacitation alter chromatin stability of ejaculated human spermatozoa? Cytochemical studies.

In vitro capacitation of human spermatozoa is commonly evaluated by the progressive motility percent. However its effects on sperm chromatin have hardly been studied. Our aim was to determine the extent to which in vitro capacitation with two treatments (B2 or human follicular fluid) alters the chromatin of human spermatozoa, by using two analytical methods, acridine orange staining and Feulgen-DNA cytophotometric measures. Ejaculates were obtained from 23 men participating in our in vitro fertilization program, and several measurements were made on the same ejaculate for each subject. No alteration was observed for the percent of native DNA after capacitation in B2, but spermatozoa incubation during the same time in human follicular fluid was followed by a significant decrease of the percent of native DNA (P less than 0.01). Feulgen-DNA content significantly increased after capacitation in either B2 or follicular fluid (P less than 0.05, P less than 0.001 respectively), and so did sperm nuclear surface area (P less than 0.001). In this study we observed a negative correlation between Feulgen-DNA content and fertilization rate (P less than 0.02). Moreover, the greater effects on Feulgen-DNA content were observed in men with abnormal sperm, whose spontaneous percent of native DNA was lower (P less than 0.05) and Feulgen-DNA content higher (P less than 0.05) than in men with normal sperm. These results indicate that capacitation in B2 as well as in human follicular fluid may alter the chromatin stability of human spermatozoa. Such results suggest a partial decondensation state of human spermatozoa during in vitro capacitation. However, beyond some level of decondensation, the fertilizing ability could be altered.

Acridine Orange↗
PubMed1991

Chromatin alterations induced by freeze-thawing influence the fertilizing ability of human sperm.

A previous cytochemical study revealed that chromatin alterations could be induced in frozen-thawed human sperm. In order to evaluate the biological consequences of such chromatin alterations, we evaluated the relationship between these chromatin alterations and the drastic decrease or loss of sperm fertilizing ability after freeze-thawing. Using acridine orange staining and Feulgen-DNA quantitative microspectrophotometry, the nuclear variables of sperm were compared using samples which had either recovered, or lost their fertilizing ability after freezing-thawing during artificial inseminations, despite good post-thaw motility. There was a clear decrease in Feulgen-DNA content and nuclear surface values in sperm which exhibited a loss of fertilizing ability. Thus freeze-thawing may alter the DNA/nuclear protein relationships and impair the fertilizing ability of human sperm.

Acridine Orange↗
PubMed1990

Ultrastructural changes in membranes and acrosome of human sperm during cryopreservation.

Functional ultrastructural changes in human sperm heads were evaluated following semen dilution in cryoprotective medium (with and without seminal plasma) as well as freezing/thawing. Plasma membranes were as much altered by dilution as by freezing/thawing when compared with fresh samples. The most striking effect on acrosome noted during freezing/thawing was a dramatic decline in percentage of intact spermatozoa. Acrosomal changes seemed to be less important in the fractions without seminal plasma. These deleterious effects were very demonstrable using transmission electron microscopy (TEM), rather than conventional staining. TEM is useful in obtaining more detailed information on membrane and acrosome integrity until a specific procedure to evaluate functional/physical integrity can be found. Cryopreservation in the absence of seminal plasma can be used for intrauterine insemination in AIH, AID programs with frozen semen.

Acrosome↗
PubMed1990

[Outcome of 470 pregnancies after artificial insemination with frozen sperm].

UNLABELLED: This article describes the outcome of the pregnancies conceived after AID with frozen semen in the Tours CECOS Centre between January 1st 1988 and December 31st 1986. There were 487 (including multiple pregnancies). These have been compared with a control group and with the national study conducted by INSERM in 1981. The study of the literature allows comparisons. The rate of pregnancies not resulting in a living child is not significantly different from the control series (abortions 11.4%, ectopic pregnancies 1% and in utero fetal deaths 0.4%). Pregnancies that continued: the rate of multiple pregnancies was higher (2.7%). There were more cases of bleeding (6.8% compared with 2.4%), more hypertensions (13.3% compared with 11.6%) and the same rate of premature labour (9.4%) as in the control group. The Caesarean section rate (22% as against 6%) was higher. The rate of forcepts delivery was lower (9.2% as against 12.8%). Concerning the children we found more premature babies (15.8% versus 5.6%) but no difference in the sex ratio, their height-weight as against their term, their Apgar score, morbidity or number or type of malformations (3.4%). IN CONCLUSION: the quality of the children is about the same with the proviso that the group is too small to conclude about the incidence of chromosomal abnormalities.

Abortion, Spontaneous↗
PubMed1988

[Thyroid ectopia and Basedow's disease].

Graves' disease was diagnosed in a 35-year old woman with a history of myxoedema in childhood. Clinical data, ultrasonography and radioisotope scanning showed that the disease had developed in an ectopic subhyoid thyroid gland. Although numerous thyroid diseases associated with an ectopic thyroid have been described, Graves' disease does not seem to be frequent since only one case has been published so far.

Adult↗
PubMed1988

Freezing and thawing alter chromatin stability of ejaculated human spermatozoa: fluorescence acridine orange staining and Feulgen-DNA cytophotometric studies.

Cryopreservation and freezing-thawing effects on the fertilizing ability of human spermatozoa commonly are evaluated by post-thaw motility. Various studies have depicted the ultrastructural changes caused by freezing-thawing, yet the chromatin alterations have been studied very limitedly. Our aim was to determine the extent to which freezing-thawing alters the chromatin of human spermatozoa, using two analytical methods: acridine orange staining and Feulgen-DNA cytophotometric studies. Both methods revealed a dramatic effect of freezing-thawing on sperm chromatin: the native DNA content decreased as did the Feulgen-DNA content, and sperm surface area was reduced. These results indicate an effect on DNA, diminished accessibility for Feulgen, and a decrease in nuclear surface area and prompt us to hypothesize a relationship between an "overcondensation" state for sperm chromatin after freezing-thawing and a lower conception rate for human semen after cryostorage.

Acridine Orange↗
PubMed1988

[Insulin-resistant diabetes and polycystic ovary].

The observation of one patient with insulin resistance (114 unités of soluble insulin in 3 injections per day + 54 units of medium acting insulin at 8 pm) associated with a polycystic ovarian disease prompted us to discuss the relationship between hyperandrogenism, acanthosis nigricans and endogenous hyperinsulinism. An in vitro study of the insulin binding to patient's erythrocytes allowed to diagnose the rare Type A insulin-resistance syndrome proposed by Kahn.

Adolescent↗
PubMed1987

[Study of the plethysmographic amplification factor during vasodilator treatment. Healthy subject versus primary Raynaud phenomenon].

Digital arterial circulation before and after administration of a vasodilator orally was explored by mercury gauge pulsed plethysmography and photoplethysmography in 12 patients with primary Raynaud's phenomenon and results compared with those of 10 healthy volunteers. The amplification factor F, ratio of amplitude in reactive hyperemia over amplitude at rest was determined in the index before and after 8 mg daily of dihydroergokryptine over 4 weeks. Before treatment, for each of the two plethysmographic technics, a significant increase in mean factor F values was noted in the patients with Raynaud's phenomenon when compared with healthy controls. This is due to a decline in digital arterial flow at rest. Using the mercury gauge plethysmograph, a significant reduction in factor F was observed after vasodilator treatment corresponding to an increase in digital flow at rest without increase in flow during hyperemia. Using photoplethysmography, no significant variation in factor F was noted after treatment. Mercury gauge plethysmography, which measures global digital blood flow appears to be a more sensitive method than photoplethysmography, which measures dermal and hypodermal blood flow, for follow-up of effects of vasodilator treatment on Raynaud's phenomenon.

Adult↗
PubMedDate not supplied

[Basedow's neuropathy].

A case report of grave's neuropathy. The symptoms appeared in a treated patient when there was a biologic hypothyroidy. A total remission was observed after corticotherapy. Nevertheless, a recurrence of disease happened for reduced doses, so an orbital radiotherapy was requisited. Student of differents treatments for dysthyroid neuropathy.

Adult↗