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Biomedical subjects

F Bousquet

Publications and source records attributed to F Bousquet.

At least 19 recordsLinked to original sources

Cloning and characterization of new orphan nuclear receptors and their developmental profiles during Tenebrio metamorphosis.

Five PCR fragments corresponding to a part of the DNA-binding domain of different hormone nuclear receptors were isolated from Tenebrio molitor mRNAs. The sequence identity of three of them with known Drosophila nuclear receptors strongly suggests that they are the Tenebrio orthologs of seven-up, DHR3 and beta-FTZ-F1, and thus named Tmsvp, TmHR3 and TmFTZ-F1. The full-length sequences of the other two were established. TmHR78 is either a new receptor of the DHR78 family or the same gene which has evolved rapidly, particularly in the E domain. TmGRF belongs to the GCNF1 family and its in vitro translated product binds to the extended half site TCAAGGTCA with high affinity. The periods of expression of the corresponding transcripts in epidermal cells during Tenebrio metamorphosis were analyzed as a function of 20-hydroxyecdysone titers measured in the hemolymph of the animals taken for RNA extraction. Comparison of the expression profiles of these nuclear receptors with those observed during Drosophila metamorphosis revealed similar temporal correlations as a function of ecdysteroid variations, which further supported the sequence identity data for TmSVP, TmHR3, TmFTZ-F1 and TmHR78.

Amino Acid Sequence↗

Fetal cerebral and umbilical artery blood flow changes during pregnancy complicated by malaria.

The objectives of our study were to quantify the fetal cerebral artery and umbilical artery blood flow changes daily during a malaria crisis in a pregnant patient and evaluate the sensitivity and the specificity of Doppler indices for the prediction of acute fetal distress at the end of the pregnancy. The study, designed as a prospective and observational one, was carried out in the obstetric department of a government hospital in French Guiana, on 23 women with pregnancies complicated by malaria (age range, 23 +/- 5 years; primiparas, 30%); crisis date: 30.8 +/- 2.5 weeks of gestation; start of treatment: 3.7 +/- 1.3 days after crisis started). The main measures of outcome consisted of daily determinations of fetal Doppler indices during the crisis, evidence of fetal distress (fetal heart rate decelerations) during labor, Apgar scores after birth, gestational age at birth, mode of delivery, and birth weight. During the crisis umbilical artery resistance index increased by 5 to 20% (P < 0.05), cerebral artery resistance index decreased by 5 to 20% (P < 0.05), and CURR decreased by 10 to 35% (P < 0.01), indicating flow redistribution toward the brain. No relationship was found between the CURR value and the following data: parasitemia grade, parity, gestational age of the crisis, date and mode of delivery, and fetal weight. A change in the hypoxia index (% change in CURR during the crisis x number of days of crisis) greater than 150 was associated with abnormal fetal heart rate in 75% of the cases, and a hypoxia index lower than 150 was associated with normal fetal heart rate in 90% of the cases (sensitivity, 89%; specificity, 77%). Lastly, the combination (hypoxia index > 150 and CURR < 1) was associated with abnormal fetal heart rate in 80% of the cases, and one or two of these normal parameters were associated with normal fetal heart rate in 84.6% of the cases (sensitivity, 80%; specificity, 84%). The CURR and the hypoxia index during the malaria crisis can be used to predict acute fetal distress at delivery.

Acute Disease↗

[Pregnancy and malaria. Study of 143 cases in French Guyana].

Malaria is the most frequent infection world wide affecting pregnant women. The association of malaria and pregnancy sometimes has serious repercussions on the foetus and increases maternal morbidity. We report 143 cases of pregnant women infected by Plasmodium falciparum in French Guyana. The consequences on the fetus in this area, where the maternal premunition rate is low, are serious: the rates of prematurity, hypotrophy and stillbirth are 3 times higher among pregnant women infected by malaria. The consequences for the fetus are all more serious if the infestation is repeated or prolonged, the closer one is to delivery, and if the parity is low. The histologic study of the placenta shows a significant correlation between the placental infection and the fetal hypotrophy. We tried to detect in utero the consequences malaria infection has on the fetus: the presence of an echographic oligoamnios and alterations of the Doppler ratings would be predictive of deleterious consequences of malaria on the fetus. We emphasize the need for rapid treatment as soon as the attack begins, before serious placental lesions occur.

Female↗

[Creation of a neovagina using ultrasonography-assisted laparoscopy (modified Vecchietti technique].

Ultrasonography-assisted laparoscopic creation of a neavagina was performed on 6 patients suffering from vaginal aplasia. As the needle progress through the vesicorectal space, ultrasonography provided an accurate check of the bladder and rectal integrity, and improved the ease of the surgical procedure. Ultrasound can be considered an effective and reliable advance for laparoscopic management of vaginal aplasia.

Adolescent↗

[Fetal circulation and malaria].

OBJECTIVE: To quantity the fetal vascular changes during flare-up, and to evaluate the sensitivity and the specificity of Doppler indices for the prediction of acute fetal distress at the end of the pregnancy. METHOD: Every day of flare-up the umbilical resistance (Rp), cerebral resistance (Rc), cerebro-placental ratio (CPR = Rc/Rp), and hypoxia index (HI = delta % CPR x crisis duration) were calculated. RESULTS: Twenty-three pregnancies were investigated at St Laurent du Maroni Hospital (French Guiana). During flare-ups the Doppler placental resistance increased (placental disorder), cerebral resistance decreased (vasodilation), CPR decreased (flow redistribution toward the brain), and HI increased. An abnormal CPR (< 1) was associated with abnormal fetal heart rate (FHR) in 61.5% of the cases, a CPR > 1 was associated with a normal FHR in 80% of the cases. (sensitivity: 80%, specificity 61%). A CPR < 1 was associated with one of the abnormalities (abnormal FHR, cesarean section, abnormal Apgar) in 71% of the cases, a CPR > 1 was associated with normal delivery in 55% of the cases (sensitivity: 71.4%, Specificity 55%). A HI higher than 150 was associated with abnormal FHR in 75% of the cases, a HI < 150 was associated with normal FHR in 90% of the cases (sensitivity: 89%, specificity: 77%). Lastly the combination (HI > 150 + CPR < 1) was associated with abnormal FHR in 80% of the cases, 1 or 2 of these parameters were associated with normal FHR in 84.6% of the cases (sensitivity: 80%, specificity: 84%). The minimum CPR and the HI during malaria flare-up can be used to predict acute fetal distress at delivery.

Acute Disease↗

[Motion sickness].

Motion sickness is a general term covering sea-sickness, car-sickness, air-sickness, and space-sickness. Symptoms can occur when a person is exposed to unfamiliar movement whether real or simulated. Despite progress in the technology and comfort of modern transportation (planes, boats, and overland vehicles), a great number of travelers still experience motion sickness. Bouts are characterized by an initial phase of mild discomfort followed by neurologic and gastro-intestinal manifestations. The delay in onset depends on specific circumstances and individual susceptibility. Attacks are precipitated by conflicting sensory, visual, and vestibular signals but the underlying mechanism is unclear. Most medications used for prevention and treatment (e.g. anticholinergics and antihistamines) induce unwanted sedation. Furthermore no one drug is completely effective or preventive under all conditions.

Cholinergic Antagonists↗

[Sensory illusions in hang-gliding].

Sensory illusions in hang-gliding and para-gliding. Hang-gliding and para-gliding are at the moment booming sports. Sensory illusions are physiological phenomena sharing the wrong perception of the pilote's real position in space. These phenomena are very familiar to aeroplane pilotes, they can also be noticed on certain conditions with hang-gliding pilotes. There are many and various sensory illusions, but only illusions of vestibular origin will be dealt with in this article. Vestibular physiology is reminded with the working principle of a semicircular canal. Physiology and laws of physics explain several sensory illusions, especially when the pilote loses his visual landmarks: flying through a cloud, coriolis effect. Also some specific stages of hang-gliding foster those phenomena: spiraling downwards, self-rotation, following an asymetric closing of the parachute, spin on oneself. Therefore a previous briefing for the pilotes seems necessary.

Humans↗

Primitive cytokines and cytokine receptors in invertebrates: the sea star Asterias rubens as a model of study.

It has been previously demonstrated that the sea star axial organ is a primitive immune organ. Phagocytic, lymphoid-like cells have been characterized with properties similar to those of vertebrates. There is also evidence for an invertebrate cytokine network because IL-1 and TNF-like activities are clearly demonstrable. In addition, the authors have previously described preliminary evidence for IL-2-like activity in the sea star. In the present report, the authors obtained evidence for the presence of IL-1- and IL-2-like molecules on axial organ cells. More interestingly, the results suggested that sea star cells express structures similar to human receptors for IL-1, IL-2, IL-6 and IFN-gamma.

Animals↗

[Cystic duplication of the esophagus, a rare etiology of dysphagia. Apropos of a case].

A case of an upper oesophageal duplication in a 44 year old man was reported. Dysphagia was the only clinical signs and further examinations CT Scan, MRI performed for diagnosis. Surgical treatment (thoracotomy) was performed and postoperative complication was underlined. Cysts with oesophageal structure are unusual anomaly and surgery is difficult and dangerous.

Adult↗

CS31A capsule-like antigen as an exposure vector for heterologous antigenic determinants.

CS31A is a multimeric surface protein surrounding certain enterotoxigenic and septicemic bovine Escherichia coli strains. The possibility of using CS31A as a carrier of foreign antigenic determinants was investigated. Introduction of heterologous viral epitopes into the CS31A major subunit, ClpG, was successfully performed in the V3 region of the molecule which encodes for an immunodominant linear epitope. E. coli K-12 strains producing the hybrid CS31A molecules or the purified chimeric proteins were used for mice immunization. By using the C epitope derived from the S protein of the porcine transmissible gastroenteritis virus, significant antiviral antibody titers were elicited and seroneutralization of the virus was demonstrated, confirming that the molecular environment in V3 is favorable for antigen presentation. These results indicate that synthesis of CS31A hybrid proteins by the wild-type strain 31A could become a powerful tool for the development of oral vaccines directed against mucosal pathogens.

Amino Acid Sequence↗

Pharmacological characterization of SR 47436, a new nonpeptide AT1 subtype angiotensin II receptor antagonist.

SR 47436, 2-n-butyl-3-[(2'-(1H-tetrazol-5-yl)-biphenyl-4-yl) methyl]-1,3-diaza-spiro[4,4]non-1-en-4-one, is a new potent and selective AT1 angiotensin II (AII) receptor antagonist. It competitively inhibited [125I]AII binding to AT1 subtype receptors in rat liver membranes (IC50 = 1.7 nM) and did not interact with AT2 subtypes in rat adrenal cortical membranes. In rabbit aorta, SR 47436 inhibited contractions induced by 10 nM AII (IC50 = 4.0 nM) and shifted AII contractile response curves to the right in a parallel fashion, without total recovery of the maximal response. The potency of SR 47436 was higher than that of the lead compound, 2-n-butyl-4-chloro-5-hydroxymethyl-1-[(2'-(1H-tetrazol-5- yl)biphenyl-4-yl)methyl]imidazole (DuP 753) (rat liver binding: IC50 = 16 nM; rabbit aorta: IC50 = 26 nM), and equivalent to saralasin (IC50 = 1.8 and 2.7 nM, respectively). The high specificity of SR 47436 was demonstrated by its lack of activity (IC50 > 10 microM) on various other receptors, ionic channels and antiports and rabbit aorta contracted by norepinephrine and KCl, and its lack of inhibition of renin and converting enzyme. In conscious rats, SR 47436 as well as DuP 753 (0.1 to 3 mg/kg, i.v., and 0.3 to 30 mg/kg, p.o.) antagonized the AII-pressor response in a dose-related manner. In conscious dogs, SR 47436 (1-10 mg/kg, p.o.) was a more potent antagonist of the AII pressor response than DuP 753. In conscious chronically implanted cynomolgus monkeys, SR 47436 antagonized the AII-pressor response at 1 mg/kg (89% i.v. and 66% p.o.) much more strongly than DuP 753 at 10 mg/kg (83% i.v. and 20% p.o.).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex↗

Escherichia coli CS31A fimbriae: molecular cloning, expression and homology with the K88 determinant.

CS31A is a plasmid-encoded K88-related fimbrial antigen. A Sau3AI library was constructed from p31A, a 180 kb CS31A encoding plasmid, in the pSUP202 vector. Bacterial recombinant clones expressing CS31A were isolated. A 8.5 kb EcoRI-HinIII DNA fragment from one of them was subcloned in pBR322 and pHSG575 vectors, leading to pAG315 and pEH524 recombinant plasmids respectively. Escherichia coli harboring pAG315 or pEH524 expressed CS31A fimbrial antigens on their cell surface. Analysis of these plasmids in minicells showed that at least seven mature polypeptides were encoded by the EcoRI-HindIII DNA fragment, with apparent molecular masses of 76,000, 54,000, 30,000, 29,000, 28,000, 15,500 and 13,500 daltons respectively. The genetic organization of the CS31A gene cluster was determined and showed to be similar to that of the K88 operon. The nucleotide sequence homology between CS31A and K88 determinants was investigated by Southern blot hybridization at high stringency. This indicated that extensive nucleotide sequence homology exists throughout both gene clusters except for the subunit structural genes.

Alanine↗

[Trial of typological classification of the blood pressure profile over 24 hours in aged patients by Fourier analysis].

The profiles of 24-hour systolic and diastolic arterial pressures and heart rates obtained with the Bard-Sentron system were studied in 36 untreated subjects (24 women and 12 men, aged from 65 to 89 years) with normal or borderline blood pressure. Each profile was modelized by a Fourier's serie. Multivariate analysis showed that 4 first harmonics were sufficient for a good description of the values observed. A programme of redistribution in subgroups, using McQueen's reallocation method and based on diastolic pressure spectrum, divided the subjects into two groups (A and B) such that the diastolic pressure spectrum of subjects in the same group were "similar" and those of subjects in different groups were "dissimilar". Subjects in both groups were of the same age and had the same man/woman ratio. The diastolic profile of group A showed marked day-night variations, while that of group B had almost the same level day and night. The same method can be applied to systolic pressure. Although the exact role of ambulatory blood pressure as a risk factor remains to be determined, a strong day-night variation of pressure observed in a given subject ought to be closely watched by the clinician. This study suggests a method to evaluate the different types of arterial pressure and heart rate profiles in any population of subjects and to identify a group at higher cardiovascular risk, if it is present.

Aged↗