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D Cabrol

Publications and source records attributed to D Cabrol.

106 records · Page 6Linked to original sources
PubMed1984

Experimental and theoretical conformational studies on polypeptide models of collagen. Poly(Gly-Pro-Ile) and poly(Gly-Ile-Pro).

The synthetic polytripeptides poly(Gly-Pro-Ile) and poly(Gly-Ile-Pro) were studied both experimentally (mainly by circular dichroism spectroscopy) and theoretically by quantum mechanical methods. Poly(Gly-Ile-Pro) adopts a collagen-like structure under favourable conditions while the isomeric poly(Gly-Pro-Ile) does not. Theoretical studies emphasize severe intrastrand interactions which limit the main chain conformations in the case of poly(Gly-Ile-Pro). On the other hand, both the side cahin and the backbone in poly(Gly-Pro-Ile) can take up many different local conformations. Therefore, it seems that the conformational behaviour of synthetic polytripeptides can be at least partially explained in terms of local interactions.

Amino Acid Sequence↗
PubMed1982

Electrical activity of the pregnant uterus in the cynomolgus monkey.

Electromyographic activity in six pregnant cynomolgus monkeys was recorded in vivo by means of bipolar electrodes individually attached to the surface of the uterine corpus. These data were compared with recordings of intra-amniotic pressure obtained simultaneously by means of an open-ended, fluid-filled catheter placed in the amniotic cavity. During the last third of pregnancy, the electromyograms showed recurrent electrical complexes (trains of potentials, TOP) which lasted for about 2 minutes and whose rate of occurrence varied during the nyctohemeral period. The initiation of electrical activity in various uterine areas was always synchronous with and was related to mechanical contraction. The complex, polyphasic contractions that were observed can be explained, largely, by the variations of potentials within a train of potentials. However, a simple quantitative relationship between the mean frequency of the potentials within the TOP and the mean amplitude of the change in pressure could not be demonstrated. In contrast to data available on the woman, the increase in contractile strength at the onset of labor in the macaque appears to be due to a higher frequency of excitation of individual cells rather than the result of an improved functional coordination between the active muscular elements.

Action Potentials↗
PubMed1980

Variations in the distribution of glycosaminoglycans in the uterine cervix of the pregnant woman.

A study was made of the modifications of glycosaminoglycans in the uterine cervix and the relationship to gestation. These substances are essential constituents of connective tissue, and a modification of their concentration could affect the physical and chemical characteristics of the cervix. Glycosaminoglycans were extracted from cervical biopsies obtained from pregnant and non-pregnant women. This study showed dermatan sulfte to be quantitatively the most important glycosaminoglycan in the cervix of both the groups studied, and that a significant decrease in the concentration of both dermatan sulfate and chondroitin sulfates occurred in the biopsies obtained just after delivery. This was related to a decrease of collagen in the cervix at the end of gestation, as the proteoglycans containing dermatan sulfate are principally associated with collagen.

Adult↗
PubMed1980

[Cervical muscular tissue in pregnant women and Macaca monkey females. Functional evaluation "in vivo" using an electrophysiological technique].

In vivo recordings of electrophysiological activity of the muscular tissue in the cervix, in both the pregnant human female and Macaca monkey, showed that most of the cervix did not present a measureable electrical activity. Only muscular tissue located in the peripheral, supra vaginal portion of the cervix, exhibited a noticeable propagated E.M.G. activity, which always originated in the fundus. This accords well with histological studies which demonstrate that this portion of the cervix is the richest in muscular tissue. It is however possible that the other muscular cells of the cervix have a role other than a contractile one, and may be responsible for synthetizing or catabolizing constituant parts of the cervical connective tissue.

Adult↗
PubMed1975

[Fistulae in esophageal surgery. (Solidity of the esophageal wall and the role of infection)].

The strength of the eosophageal wall has been tested in 20 autopsy specimens: it proved to be as resistant as the stomach and the jejunum. It dépends as elsewhere in the digestive tract on the deep layer of the mucosa (Halstedt's submucosa): the success of an anastomosis depends on the passage of sutures through this submucosa. Vascularization does not seem to be a problem, provided certain precautions are taken. The necrotizing properties of saliva and infection especially in cancerous surgery might be the main causes of fistulas.

Esophageal Diseases↗
PubMedDate not supplied

Sonographic measurement of the fetal iliac angle cannot be used alone as a marker for trisomy 21.

The fetal iliac wings angle was studied in 255 fetuses before amniocentesis at 16.7 weeks (+/- 1.3), using a sonographic axial view of the fetal pelvis. The measurement could be performed in 208 fetuses (81.6%), of whom 4 had trisomy 21 (T 21). The mean iliac angle was greater in fetuses with T 21 than in normal fetuses (69.8 degrees vs. 88.7 degrees; p = 0.03). This measurement is subject to significant intra- and interexaminer variability (interclass correlation coefficient: 0.65 and 0.23, respectively). When a 90 degrees value is used as a threshold, specificity, sensitivity, positive and negative predictive values are, respectively, 80, 75, 7. 0 and 99.4%. The 20% rate of false-positives rules out the use of this measurement as the sole criterion for the indication of amniocentesis for T 21 antenatal diagnosis.

Down Syndrome↗
PubMedDate not supplied

Second- and third-trimester therapeutic terminations of pregnancy in cases with complete placenta previa--does feticide decrease postdelivery maternal hemorrhage?

OBJECTIVE: To study the feasibility of second- and third-trimester termination of pregnancy (TOP) with complete placenta previa, and the impact of performing feticide before labor induction on maternal hemorrhagic morbidity. PATIENTS AND METHODS: From 1987 to 2002, the databases of two referral hospitals were reviewed. We identified 15 cases of second- or third-trimester TOP in women with complete placenta previa. Feticide was performed 2-14 days before induction in 6/15 cases. Cervical ripening was achieved in 8 cases by mifepristone alone (n = 2) or by mifepristone and dilapan (n = 6). Labor was induced by vaginal gemeprost (n = 2), intramuscular (n = 5) or intravenous (n = 4) sulprostone, vaginal misoprostol (n = 1) or a combination of misoprostol and sulprostone (n = 3). Hemorrhage was defined by the need for transfusion. The difference between the preoperative and the lowest per- or postoperative maternal hemoglobin level was also analyzed. RESULTS: Of the 9 women who underwent labor induction without previous feticide, 4 required blood transfusions, 1 of whom had a hemostat hysterectomy. The mean hemoglobin difference was 2.5 g/dl (range: 0.5-5.3). None of the 6 patients with preinduction feticide required transfusion. The hemoglobin difference was significantly smaller in this group than in terminations without previous feticide (mean: 1.0 g/dl ; range: 0.1-2.2; p = 0.03). CONCLUSION: In cases with complete placenta previa, second- or third-trimester TOP is feasible. It carries a substantial risk of hemorrhage that might be decreased by preinduction feticide.

Abortion, Therapeutic↗
PubMedDate not supplied

Fetal pulmonary artery Doppler waveform: a preliminary report.

OBJECTIVE: The study of fetal lung circulation by means of pulmonary Doppler investigation. METHODS: Pulmonary Doppler ultrasound obtained with color pulsed-Doppler with a 3.5- to 5-MHz probe. Measure of resistance index and pulsatility index. PATIENTS: 47 pregnant women with singleton, between 18 and 39.5 weeks of gestation, were recruited to have pulmonary Doppler ultrasound. Seven fetuses had intrauterine fetal growth retardation (IUGR). Overall, 50 Doppler velocity waveforms were measured. RESULTS: Resistance and pulsatility index were measured in all patients and at each examination. Resistance index (0.86 +/- 0.03) and pulsatility index (2.46 +/- 0.34) were found to be stable during pregnancy. Pulmonary pulsatility index in IUGR fetuses (2.71 +/- 0.33) were found to be higher than those in normotrophic infants (p = 0.006), whereas no difference was found in resistance index between the same subgroups. Moreover, no difference was found in pulsatility index measurements between preterm small-for-gestational age fetuses and normotrophic fetuses measured between 36 and 39.5 weeks of gestation (2.68 +/- 0.31 vs. 2.49 +/- 0.28). CONCLUSION: Pulmonary resistance index is not statistically different between normotrophic and IUGR fetuses. In contrast, pulmonary pulsatility index is significantly higher in IUGR fetuses when compared to normotrophic fetuses. Pulmonary Doppler ultrasound should be evaluated in a larger trial and correlation between Doppler measurements and fetal lung maturation should be studied.

Female↗
PubMedDate not supplied

Strip test for bedside detection of interleukin-6 in cervical secretions is predictive for impending preterm delivery.

Inflammatory cytokines in amniotic fluid are markers of prematurity which could characterize preterm labour of infectious origin. To avoid amniocentesis, we analyzed IL-6, IL-8, IL-10, and IL-13 by RT-PCR in cervical secretions (CS) of 307 women with preterm labour. IL-6 was detected in 26.3% patients who delivered at less than 34 weeks (specificity: 95.8%). In addition, IL-6 was associated with delivery within 7 days (specificity: 91.6%). To render the detection more rapid and cheaper, a strip test was designed and evaluated comparatively with RT-PCR in 76 women. This bedside strip test was twice more sensitive than RT-PCR, with little decrease in specificity.

Cervix Uteri↗
PubMedDate not supplied

[Visualization of the guinea pig fetus in utero by x-ray densitometry].

The total body X-ray scanner (computer assisted axial tomography) was used to observe the guinea-pig fetus in utero. This new method of investigating obstetrical physiology provides a suitable animal model with quantitative facts about the density of the fetal organs and, using a non-invasive technique, allows precise intrauterine pictures of the anatomy of the fetus to be obtained.

Animals↗
PubMedDate not supplied

[Typical tripeptide sequences of collagen: quantitative conformation study].

Theoretical and experimental investigations on the conformations of synthetic polytripeptides, with Gly-R2-R3 general repetitive sequence, are of great interest for the comprehension of the factors which contribute to the triple helix stabilization. Using appropriate molecules as models, we have investigated by the PCILO method the intrinsic conformational possibilities of each "in situ" residue for the following cases : Gly-imino-imino, Gly-amino-imino and Gly-imino-amino which represent the most important sequences occurring in the primary structure of collagen. The computations were carried out taking into account the two pyrrolidine ring puckerings and the preferential side-chains orientations. Extending our previous work concerning the isomeric polytripripeptides Gly-X-Pro and Gly-Pro-X with X epsilon (Pro, Phe) we have studied the cases of X epsilon (Ala, Ser). In this brief communication, we present a preliminary synthesis of these recent results.

Amino Acid Sequence↗
PubMedDate not supplied

Electrohysterography during pregnancy: preliminary report.

The purpose of this study was to test the ability of uterine electrical activity recorded by electrohysterography (EHG) from abdominal electrodes during pregnancy to provide reliable information about uterine contractions. In this preliminary study, abdominal EHG was used to monitor the uterine contractions of eight women, three of whom were having spontaneous contractions related to preterm labor and five of whom were having medical abortions after intrauterine fetal death. The EHG signal consisting of one electrical burst (EB) correlated with a single episode of mechanical activity (MA) in more than 66% of the recorded contractions. When mechanical or electrical activity identified as artifactual was excluded, the temporal correlation of EBs with MA was found in 89% of the recorded contractions. Furthermore, the electrical bursts detected had temporal and spectral characteristics similar to those described previously. Reliable detection of mechanical activity during early pregnancy remains problematic. Nevertheless, abdominal EHG appears suitable for noninvasive monitoring of pregnancies at risk. Further studies are needed to elucidate the significance of the EHG signal in both normal and abnormal pregnancies. It may eventually be possible to use EHG as an ambulatory monitoring tool for the early diagnosis of preterm labor.

Abortion, Induced↗