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R Bessis

Publications and source records attributed to R Bessis.

At least 19 recordsLinked to original sources

[What's new in fetal medicine?].

One of the major progress in fetal medicine in recent years is the increased sensitivity of sonographic screening for foetal malformations, due to technical improvement but also to a better training of professionals. Screening for chromosomal abnormalities is no longer based on maternal age alone. Second trimester maternal serum screening (MSS) is increasingly used: thus in 1997, 376,798 MSS tests were performed in France, yielding to the prenatal diagnosis of 391 cases of Down's syndrome. First trimester sonographic nuchal translucency measurement (NTM) is an effective screening method when performed under stringent conditions. Quality control however, is more difficult to implement on a large scale for NTM than for MSS. Performing screening tests sequentially carries a danger of generating an unnecessarily high number of amniocentesis, which may be obviated by a rational calculation of an individual's risk to carry an aneuploid baby. First trimester MSS is expected to become standard practice in the next years, probably in combination with NTM. Cytogenetics underwent substantial innovations recently, due to the ever-increasing use of molecular cytogenetics. FISH techniques allow: 1) precise analysis of unexpected structural chromosomal abnormalities diagnosed by routine amniocentesis, 2) rapid screening of the most common aneuploidies by amniocentesis when a fetal structural anomaly is detected by 3rd trimester ultrasound, 3) diagnosis of micro-deletions suspected by fetal ultrasound or post-mortem. Prenatal diagnosis by maternal blood sampling and fetal cells or DNA analysis is now part of routine clinical practice in selected cases, such as fetal sexing in families affected by an X linked disease. Thus one can select those pregnancies eligible to invasive prenatal diagnosis. Pre implantation diagnosis, which has not been legal in France until 1999 is now increasingly used as an alternative to first trimester diagnosis. As for fetal therapy, a major recent breakthrough is the prenatal management of twin to twin transfusion syndrome by either amnioreduction or laser coagulation of inter-twin vascular shunts. In addition, new pathophysiologic concepts involving the renin angiotestin system could lead to further therapeutic innovations. A European randomised trial is now being completed to establish the respective indications of drainage and Laser. All this underscores that fetal medicine is no longer solely a succession of dramatic technical breakthroughs, but is entered an era of large-scale diffusion that requires evidence based evaluation.

Adult↗

Successful intrauterine shunting of a sacrococcygeal teratoma (SCT) causing fetal bladder obstruction.

We report a case of a sacrococcygeal teratoma (SCT) diagnosed at 22 weeks with a substantial intrapelvic cystic extension leading to bladder outlet obstruction and hydronephrosis at 27 weeks. Prenatal percutaneous shunting of the cystic teratoma was performed at 28 weeks to avoid prolonged fetal pelvic compression by the tumour that could have adverse effects by stretching the pelvic plexus and sacral nerves. Urinary dilatation resolved completely after shunting and a 3880 g baby girl was delivered at 39 weeks. The potential benefits of in utero shunting to avoid urological complications of SCTs with intrapelvic extension are discussed.

Adult↗

Stilbene content of mature Vitis vinifera berries in response to UV-C elicitation.

A method using HPLC analysis has been used to compare the level of resveratrol and its derivatives, piceid, pterostilbene and epsilon-viniferin, in grapevine berries of three Vitis vinifera varieties. The concentration of these compounds has been evaluated in healthy and Botrytis cinerea infected grape clusters, both in natural vineyard conditions and in response to UV elicitation.

Chromatography, High Pressure Liquid↗

Changes in the phytoalexin content of various Vitis spp. in response to ultraviolet C elicitation.

The phytoalexin production potential of three American Vitis species and that of three cultivars of Vitis vinifera were evaluated in response to UV-C irradiation. Time course changes in resveratrol, piceid, epsilon-viniferin, and pterostilbene contents were studied within 3 days after a short UV-C irradiation. Results show that the two major stilbenes accumulated as a response to UV-C elicitation are resveratrol and epsilon-viniferin, a resveratrol dehydrodimer, the concentration of both compounds usually reaching quantities >100 microgram/g of fresh weight. In contrast, piceid and pterostilbene were constantly produced in low quantities. Owing to the results obtained, the role of stilbene phytoalexins in the resistance of grapevines to diseases is discussed.

Plant Extracts↗

Cystic fibrosis screening: a fetus with hyperechogenic bowel may be the index case.

BACKGROUND: The potential of hyperechogenic fetal bowel to act as a hallmark for prenatal cystic fibrosis screening in the general population is controversial. METHODS: Our goal was to evaluate the incidence of cystic fibrosis in 209 fetuses with hyperechogenic bowel diagnosed at routine ultrasonography and with no family history of cystic fibrosis. The diagnosis of cystic fibrosis was based on prenatal screening for the eight mutations most frequently observed in France (deltaF508, deltaI507, 1717-1G-->A, G542X, G551D, R553X, W1282X, N1303K) and at postnatal follow up. RESULTS: The overall incidence of cystic fibrosis was 7/209 (3.3%) which is 84 times the estimated risk of CF in the general population (112500). Of these seven cases, six were diagnosed prenatally based on DNA analysis (deltaF508/deltaF508, n=5; deltaF508/G542X, n=1). One case in which only one mutation had been recognised was diagnosed clinically after birth (deltaF508/unidentified mutation). Of the seven cases, none was diagnosed at 16-19 weeks, four at 16-24 weeks, and three after this. The incidence of heterozygous fetuses (15/209, 7%) was not significantly higher than the 5% expected in the general population. The mutations involved in these heterozygous cases were deltaF508 (n=13), G542X (n=1), and G551D (n=1). CONCLUSIONS: Screening for cystic fibrosis should be offered to families in which fetal hyperechogenic bowel is diagnosed at routine ultrasonography. This underlines the need to review genetic counselling in this situation where the fetus is the index case for a genetic disease.

Cystic Fibrosis↗

[Reccurent abortions: unpublished syndrome suggesting the explanation of fetal death].

A report is given of 8 cases of recurrent "idiopathic" abortions sharing in common the following features, unreported so far: (1) high uterine arterial impedance; (2) decrease in endometrial thickness, in spite of normal hormonal and endometrial cycle at biopsy; (3) a history of previous curettages. Such a syndrome could be consistent with the existence of a narrow peripheral symphysis of the uterine cavity, unaffecting its shape at hysterography.

Abortion, Habitual↗

[Value in gynecology of transvaginal pulsed and color Doppler. Study of ovarian vascularization].

Recently, pulsed Doppler has become available on high resolution vaginal ultrasound probes for studying ovarian blood flow. Doppler studies of ovarian blood flow are based on: semiquantitative analysis of Doppler flow waves recorded over the ovarian artery at its entry into the ovary; color Doppler mapping of intraovarian vessels. Semiquantitative analysis of the ovarian artery Doppler flow waves suffers from frequent difficulties at properly identifying the ovarian artery, particularly in multiparous women. Mapping of intraovarian vessels however, appears a most promising feature of vaginal Doppler for studying ovarian blood flow, provided that the proper ultrasound equipment is used. Specifically, transvaginal color Doppler mapping of intraovarian vessels allows for a positive visual detection of the onset of the ovulatory process prior to the actual follicular rupture. Thus, color Doppler mapping of ovarian vessels permits an improved and simplified approach for timing intercourses and inseminations in infertility patients. In controlled ovarian hyperstimulation (COH) used for in vitro fertilization (IVF), mapping of intraovarian vessels by color Doppler offers a fascinating new insight into normal and pathological responses of ovarian follicles to hCG. Finely, color Doppler appears a very promising asset to transvaginal ultrasounds for sorting suspicious ovarian cysts from their benign counter parts. In conclusion, we think that vaginal Doppler should be considered as a marvelous refinement of ultrasounds rather than as a truly new diagnostic tool. Yet vaginal color Doppler carries the potential for markedly improving the sensitivity and the specificity of vaginal ultrasound, particularly for diagnosing benign from potentially malignant ovarian conditions.

Arteries↗

[Accidental ultrasonographic disclosure of isolated intra-abdominal fetal hyperechogenicity. Apropos of a series of 87 cases].

Having seen 87 cases we will now attempt to refine the management to be carried out when intra-abdominal hyperechogenic masses are found in the fetus. Before the 20th week of amenorrhoea (47 cases) amniocentesis can be used to study the digestive enzymes to determine the fetal karyotype. The normal results for intestinal enzymes makes it possible to rule out fetal cystic fibrosis. Three karyotype abnormalities were found in this series. After the 20th week (40 cases) intestinal enzymes cannot be interpreted. The diagnosis of cystic fibrosis then must rely on Delta F 508 mutation; but the absence of this mutation does not exclude cystic fibrosis. When ultrasound signs of intra-abdominal hyperechogenicity are found the diagnosis of cystic fibrosis should not be thought of first, because in this series the majority of fetuses who had this sign were born without any malformation. Four cases of cystic fibrosis that were confirmed have been found but equally there were other serious malformations, three chromosome abnormalities, four intestinal atresias, ten unexplained intra-uterine deaths and one case of biliary duct atresia.

Amniotic Fluid↗

[Vaginal echography in ovulation monitoring excluding in vitro fertilization].

Vaginal ultrasonography makes it possible to observe follicles which remain hidden from abdominal ultrasonography, but provides a less accurate measurement of the diameter of large follicles. The vaginal route improves the observations of the endometrium, eliminates certain artifacts in the exploration of ovarian cysts and considerably enhances the accuracy of diagnosis of ectopic pregnancies. The limits of the method must, however, be recognized, and it demands very wide experience on the part of the ultrasonographer.

Female↗

[Fortuitous discovery in echography of an isolated fetal intra-abdominal hyperechogenic mass. 87 cases].

Having seen 87 cases we will now attempt to refine the management to be carried out when intra-abdominal hyperechogenic masses are found in the fetus. Before the 20th week of amenorrhoea (47 cases) amniocentesis can be used to study the digestive enzymes to determine the fetal karyotype. The normal results for intestinal enzymes makes it possible to rule out fetal cystic fibrosis. Three karyotype abnormalities were found in this series. After the 20th week (40 cases) intestinal enzymes cannot be interpreted. The diagnosis of cystic fibrosis then must rely on Delta F 508 mutation; but the absence of this mutation does not exclude cystic fibrosis. When ultrasound signs of intra-abdominal hyper-echogenicity are found the diagnosis of cystic fibrosis should not be thought of first, because in this series the majority of fetuses who had this sign were born without any malformation. Four cases of cystic fibrosis that were confirmed have been found but equally there were other serious malformations, three chromosome abnormalities, four intestinal atresias, ten unexplained intra-uterine deaths and one case of biliary duct atresia.

Amniocentesis↗

Vascular resistance of uterine arteries: physiological effects of estradiol and progesterone.

To determine if reproductive hormones played a role at physiological levels on vascular resistance of uterine arteries, we studied young women having inactive ovaries who received exogenous estradiol (E2) and progesterone (P). Six women, ages 27 to 36 with absent or nonfunctioning ovaries, received transdermal E2 and vaginal P after a 28-day replacement regimen duplicating E2 and P levels seen in the menstrual cycle. Vascular resistance of uterine arteries was evaluated before treatment (baseline), on days 13 to 14 and on days 26 to 27, using transvaginal pulsed Doppler combined with real-time imaging. Doppler waveforms were analyzed by the pulsatility index (PI). Baseline evaluation showed narrow systolic Doppler flow waves with a PI of 5.2 +/- 0.4, mean +/- SEM. On cycle day 13, Doppler waveforms showed a marked broadening with uninterrupted diastolic flow indicative of a profound decrease in vascular resistance. This was reflected by a significant decrease in PI to 1.3 +/- 0.3, mean +/- SEM. Doppler measurements made on days 26 to 27 showed no significant change. Our results indicate that at physiological levels, E2 affects vascular resistance of uterine arteries. This represents a new parameter of estrogen action, readily measurable by a noninvasive technique that, in the future, may help for assessing the efficacy of various estrogenic treatments.

Adult↗

Transfusion syndrome in a triplet pregnancy.

A case is reported of a transfusion syndrome in a triplet pregnancy with intrauterine death of two of the fetuses. This is an exceptional occurrence in a triplet pregnancy and raises the problem of the management of multiple pregnancies associated with the death of one or more of the fetuses. The problem of the method of delivery and the complications arising in triplet dizygotic pregnancies is discussed.

Adult↗

[Ureterocele: diagnosis and treatment at birth].

Antenatal ultrasound diagnosis of ureterocele remains difficult. Two cases are presented. The presumption of the diagnosis was realized at 25 weeks of amenorrhea in one case; in the other case, the diagnosis was sure at 38 weeks. A vesical exploration was performed after visualization of a dilatation of the upper pole of the kidney associated with an ureteral distension. An ectopic ureterocele was display in one case and an orthotopic ureterocele in the other case. These findings were confirmed during the radiologic examination after the birth. An hemi-nephroureterectomy was realized for an ectopic ureterocele in the first case, and an enucleation for an orthotopic bilateral ureterocele in the second case. doses of 1 and 100 micrograms+100 g BW, T3 was without effect of inhibited 45Ca uptake. In ventricles and atria, the stimulatory effect of T3 on 45Ca uptake was very rapid [within 2 min, at which time it was at or near maximum (50-90% above control] and then declined gradually and was not seen after 10-20 min. Of the several calcium blockers employees, verapamil (organic) and cadmium (inorganic) were found to be the most effective. Verapamil and cadmium produced a rapid, transient, and dose-related inhibition of 45Ca uptake in the tissues examined (except fat tissue where, under the experimental conditions employed, 45Ca uptake was undetected). Verapamil, given iv (200 micrograms/100 g BW) or ip (1 mg+100 g BW), reduced tissue 45Ca uptake by 50-90% within 2 or 10 min, respectively, and then its inhibitory effect diminished rapidly and was not seen after 20-30 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

[Morphological aspects of lethal chromosome errors].

Correlations have been established between phenotype and karyotype in spontaneously aborted specimens. The criteria used to determine the phenotype were based on estimated developmental age and macroscopic examination of embryo and placenta, taking into account the morphological modifications due to in utero retention. The probability that a chromosomal aberration was the cause of the abortion is high when the developmental arrest occurred before 5-6 weeks and the expulsion was delayed. The frequency could be estimated at 75% when the developmental arrest was at 2-3 weeks, and 65% when the developmental stage reached 5-6 weeks. Main anatomical features are described permitting an attempt to assign the type of chromosomal anomaly by ultrasonographic examination.

Abortion, Spontaneous↗

Longitudinal follow-up of 100 patients at risk of intrauterine growth retardation: comparison of diagnosis in two periods.

The concept of low birth weight includes two different entities: prematurity and intrauterine growth retardation. Both of them are major public health problems, because they increase perinatal morbidity and mortality Early diagnosis of IUGR leads to adequate decisions, making possible a reduction in perinatal morbidity and mortality. In order to make an early diagnosis of IUGR, clinical methods have proven to be insufficient. Ultrasonography is an important aid to this diagnosis, introducing the measurement of fetal diameters and perimeters. This study, designed to compare both methods, was carried out in at the Antoine Béclère Hospital, Clamart, France. Data processing was done in CLAP-PAHO/WHO. In the first period, retrospective analyses of 116 clinical histories with IUGR were performed. In this study, only fetal diameters were used and the accuracy of clinical and ultrasonographic diagnosis was evaluated. In the second period a prospective longitudinal follow-up study of 100 pregnant women at risk of developing IUGR was carried out. Clinical diagnosis was also evaluated, and compared to the ultrasonographic approach. The parameters used were the fetal diameters and perimeters (head and abdominal perimeters, and their relationship). Sensitivity, specificity and predictive values of the ultrasonic parameters were calculated (table I). The clinical and ultrasonographic diagnosis of both periods were compared with the purpose to analyze the effect of the measurement of fetal perimeters in the diagnostic accuracy. Newborns of the 100 patients in the prospective study were classified into two groups according to birth weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗