PubMed Health⌕ Search

Biomedical subjects

E Faure

Publications and source records attributed to E Faure.

At least 55 records · Page 3Linked to original sources
PubMed1996

UVB irradiation-induced transcription from the long terminal repeat of intracisternal A particles and UVB-induced secretion of an extracellular factor that induces transcription of the intracisternal A particles in unirradiated cells.

Intracisternal A particles (IAPs) are endogenous defective retroviral-like elements encoded by a family of proviral sequences present as a thousand copies in the mouse genome. In order to analyse the regulation of the long terminal repeat (LTR) directed transcription by UVB, D152 murine cells were transfected with a chimeric construct carrying the LTR of IAP linked to the bacterial chloramphenicol-acetyl-transferase reporter gene and then subjected by UVB irradiation in a dose- and time-dependent manner. Like the human immunodeficiency virus 1 type LTR and in spite of the lack of the nuclear factor kappa B consensus sequence, the IAP LTR could be activated by UVB. In addition, the D152 cells produced an extracellular factor are factors in response to UVB irradiation which activated the IAP LTR in unirradiated cells. This factor was detected both when responding cells were cocultured with inducing cells and when conditioned medium from irradiated cultures was added to the cell cultures.

3T3 Cells↗
PubMed1996

X-irradiation activates the Drosophila 1731 retrotransposon LTR and stimulates secretion of an extracellular factor that induces the 1731-LTR transcription in nonirradiated cells.

Using constructs expressing the reporter gene under the control of the entire or deleted long terminal repeats (LTRs) of 1731, a Drosophila melanogaster retrotransposable element, we show that 1731-LTR is activated by X-irradiation in a dose- and time-dependent manner, and that a sequence located in the U3 region of these LTRs is required. The cis-acting element conferring X-responsiveness shows similarities to kappa B (kappa B)-like binding sequence. In response to X-irradiation, S2 Drosophila cells produced an extracellular factor which activates the 1731-LTR in nonirradiated cells. This factor was detected both when transfected cells were cocultured with inducing cells and when a conditioned medium taken from irradiated cultures was added.

Animals↗
PubMed1996

UVB irradiation upregulation of the Drosophila 1731 retrotransposon LTR requires the same short sequence of U3 region in a human epithelial cell line as in Drosophila cells.

Phylogenetic analysis of the retrotransposon and retrovirus suggests an evolutionary relationship between them and indicates that transactivation of the long terminal repeat (LTR)-containing retroelements could be ubiquitous. Using constructs expressing a reporter gene under the control of the entire or deleted LTR of 1731, which is a retrotransposable element of Drosophila melanogaster, we were able to show that the UVB-irradiation activation of the 1731-LTR requires the same short sequence of U3 region in a human epithelial cell line as in Schneider's Drosophila cell line (S2). This sequence is similar to the binding sequence of the members of the nuclear factor-kappa B (NF-kappa B)/rel family. In addition, human colonic carcinoma cells (HT29), in response to UVB-irradiation, produce some extracellular factor(s) that activates the 1731-LTR in nonirradiated cells.

Animals↗
PubMed1996

Activation of the transcription from the human immunodeficiency virus type 1 (HIV-1) long terminal repeat by autologous and heterologous cell-to-cell contact.

Recent studies have demonstrated that the activation of HIV-1 provirus and of the Long Terminal Repeat of HIV-1 (HIV-1-LTR) may occur upon cell-to-cell contact between peripheral blood lymphocytes (PBLs) and infected or transfected (HT29) human colonic carcinoma cells. Using transient or stable transfections, we ascertained that the HIV-1 LTR was up-regulated by cell-to-cell contact in various cell lines. The degree of cell-to-cell contact responsiveness was cell type dependent. In contrast, in transient transfection, the HIV-1-LTR was strongly induced by Tat expression in all cell types tested. This indicates that there are differences in the induction mechanism for these two stimuli, even though Tat protein has been previously reported to induce cell adhesion. Except for the PBLs/transfected cells interactions, the results also demonstrate that the cell-to-cell contact-induced HIV-1-LTR activation was highest after contact between autologous as compared to heterologous cells. Previous experiments have shown that, in HT29 cells, cell-to-cell contact activation of the HIV-1-LTR involved the NF-kappa B tandem binding site and activates DNA binding of the nuclear factor NF-kappa B. In this work, we show that in a stably transfected cell line, the principal enhancer element was also involved in the HIV-1-LTR cell-to-cell contact activation. On the other hand, in the HT29 cell line, the NF-kappa B binding appeared to involve the RGD motif of the cell-binding domain, which indicates that a post-integrin receptor event could be implicated.

Cell Communication↗
PubMed1995

Insensitivity to anti-müllerian hormone due to a mutation in the human anti-müllerian hormone receptor.

Anti-Müllerian hormone (AMH) and its receptor are involved in the regression of Müllerian ducts in male fetuses. We have now cloned and mapped the human AMH receptor gene and provide genetic proof that it is required for AMH signalling, by identifying a mutation in the AMH receptor in a patient with persistent Müllerian duct syndrome. The mutation destroys the invariant dinucleotide at the 5' end of the second intron, generating two abnormal mRNAs, one missing the second exon, required for ligand binding, and the other incorporating the first 12 bases of the second intron. The similar phenotypes observed in AMH-deficient and AMH receptor-deficient individuals indicate that the AMH signalling machinery is remarkably simple, consisting of one ligand and one type II receptor.

Alternative Splicing↗
PubMed1995

X irradiation-induced transcription from the HIV type 1 long terminal repeat.

It has been previously shown in vitro and in vivo that the human immunodeficiency virus type 1 can be dramatically enhanced by certain heterologous viral, chemical, and physical (ultraviolet irradiation) agents. A common denominator shared by these agents is their ability to cause stress responses in cells. To analyze if a similar effect could occur by X irradiations, we tested the in vitro effect of X rays on HIV LTR-directed gene expression. The results demonstrate that the HIV-1 LTR is activated by X irradiation in a dose- and time-dependent manner, in all cell types tested, including epitheloid, fibroblast, and lymphoid cell lines. This study raises the possibility that exposure of AIDS patients to ionizing radiation (e.g., during treatment of epidemic Kaposi's sarcoma) could play a role in the activation of HIV-1 in vivo.

Cell Line↗
PubMed1995

Peripheral neuropathy in subclinical hypothyroidism.

Alterations in peripheral nerves are well documented in overt myxedema but not in subclinical hypothyroidism. We performed electrophysiologic studies to investigate such abnormalities in patients with normal serum total T4 and hyperresponsiveness of TSH to TRH, either with normal or high levels of basal circulating TSH. Subjects were divided in three groups: (i) Hypothyroidism Stage I (group () (n = 17, mean age = 39 +/- 34 years), T4 = 9 +/- 0.7 micrograms/dL, TSH = 4.3 +/- 0.4 microU/mL, sTSH post-TRH (peak value) = 37.6 +/- 1.6 microU/mL; (ii) Hypothyroidism Stage II (group II) (n = 10, mean age: 43 +/- 6 years), T4 = 7.7 +/- 0.8 microgram/dL, TSH = 20 +/- 5 microU/mL, TSH post-TRH > 50 microU/mL; (iii) Control Group (n = 20, mean age 41 +/- 5 years), healthy subjects. All patients and controls were women. TRH test consisted in the i.v. injection of 200 micrograms TRH (normal peak value up to 25 microU/mL, normal basal TSH < 5.5 microU/mL. None of the patients had carpal tunnel syndrome or any other neurological or metabolic disturbances. We studied the distal motor latencies, motor and sensory amplitudes, and nerve conduction velocities. The motor parameters were measured in the median and external sciatic popliteal (ESP) nerves, and the sensory parameters in the median and sural nerves. In most cases values were obtained from both right and left nerves. Motor parameters: no differences were found between all groups for conduction velocities (CV).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Physical contact with lymphocytes is required for reactivation of dormant HIV-1 in colonic epithelial cells: involvement of the HIV-1 LTR.

HIV-1 transmission from mucosal epithelial cells to lymphocytes is a potential mechanism of HIV-1 contamination during sexual intercourse. The human colon epithelial cell line HT-29, that is infectable by various HIV-1 strains, is a useful model for studying the molecular mechanisms involved in this process. In the present study, we show that HT-29 cells, when exposed to either HIV-1(LAI) or HIV-1(NDK) at a low multiplicity of infection, became infected but did not produce infectious virions. Using two-compartment cell culture chambers separated by a porous membrane, we showed that PBL were able to rescue infectious HIV-1 from latently infected HT-29 cells following a physical interaction between the two cell populations. In contrast, HT-29 cells, infected with the same viruses at a high multiplicity of infection, were able to produce mature viral particles that were infectious to PBL in absence of cellular contacts. Transient expression assays using an indicator gene under the control of the HIV-1 long terminal repeat revealed that cell-to-cell contact induced an activation of the HIV-1 promoter. These observations provide a putative molecular mechanism for transmission of HIV-1 from mucosal epithelial cells to lymphocytes.

Cell Communication↗
PubMed1994

Cloning, expression, and alternative splicing of the receptor for anti-Müllerian hormone.

Anti-Müllerian hormone, also called Müllerian-inhibiting substance or factor, is a glycoprotein dimer belonging to the transforming growth factor-beta superfamily and synthesized by immature Sertoli cells and postnatal granulosa cells. Anti-Müllerian hormone plays a key role in sex differentiation by inducing the regression of Müllerian ducts in the male fetus. It is also responsible for the stunting and masculinization of fetal ovaries in bovine freemartin fetuses and may be involved in the control of follicular maturation in the postnatal ovary. Using a degenerate probe for a consensus region of the transforming growth factor-beta receptor superfamily to screen a complementary DNA library from rabbit fetal ovaries, we cloned a complementary DNA coding for a transmembrane serine/threonine kinase, which is expressed around the fetal Müllerian duct, in fetal and adult granulosa cells, and in immature Sertoli cells. Two transcripts, generated by alternative splicing of an exon coding for an N-terminal 61-amino acid domain, are strongly expressed in anti-Müllerian hormone target organs and Sertoli cells. The longer, 569-amino acid, isoform binds anti-Müllerian hormone when transiently expressed in COS cells and is believed to encode its functional receptor.

Amino Acid Sequence↗
PubMed1994

[Associated lipid pneumonia and bronchiolo-alveolar carcinoma].

The authors report a new case of bronchio-alveolar carcinoma which developed on a background of iatrogenic exogenous lipid pneumonia; this association is extremely rare (less than 20 cases in the literature) and poses the problem of possible cancer developing in the centre of the lipid pneumonia.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1992

Intratumor treatment of C3H mouse mammary carcinoma with 5-fluorouracil adsorbed on activated charcoal particles.

A dosage form comprising 5-fluorouracil (5-FU, 25 mg/ml) adsorbed on a suspension of micronized charcoal (100 mg/ml) 2-5 microns in diameter, adsorbing 5-FU in aqueous solution was studied for intratumor treatment of mammary carcinoma in animal experiments. An in vitro desorption method is described to determine the amount of 5-FU adsorbed on activated charcoal particles which would be released once the drug concentration decreased around the charcoal. In vivo results indicate that an intratumor injection of 5-FU adsorbed on activated charcoal particles is a highly effective method for achieving tumor regression without increasing toxicity.

Adenocarcinoma↗
PubMed1991

Characterization of endoglucanase A from Clostridium cellulolyticum.

A construction was carried out to obtain a high level of expression in Escherichia coli of the gene celCCA, coding for the endoglucanase A from Clostridium cellulolyticum (EGCCA). The enzyme was purified in two forms with different molecular weights, 51,000 and 44,000. The smaller protein was probably the result of proteolysis, although great care was taken to prevent this process from occurring. Evidence was found for the loss of the conserved reiterated domains which are characteristic of C. thermocellum and C. cellulolyticum cellulases. The two forms were extensively studied, and it was demonstrated that although they had the same pH and temperature optima, they differed in their catalytic properties. The truncated protein gave the more efficient catalytic parameters on carboxymethyl cellulose and showed improved endoglucanase characteristics, whereas the intact enzyme showed truer cellulase characteristics. The possible role of clostridial reiterated domains in the hydrolytic activity toward crystalline cellulose is discussed.

Amino Acid Sequence↗
PubMed1990

Randomized comparison of recovery after propofol-nitrous oxide versus thiopentone-isoflurane-nitrous oxide anaesthesia in patients undergoing ambulatory surgery.

A randomized, prospective study was performed to compare recovery characteristics in 41 ASA physical status I-II patients scheduled for ambulatory surgery with either propofol or thiopentone-isoflurane anaesthesia. Particular attention was focused on the recovery time needed to meet discharge criteria. The propofol group received propofol 2 mg.kg-1 for induction followed by propofol infusion (6-9 mg.kg-1.h-1) 1 min after intubation. The thiopentone-isoflurane group received thiopentone 4 mg.kg-1 for induction followed by isoflurane (0.5-2%) 1 min after endotracheal intubation. Other drugs administered during or after anaesthesia were similar between the groups. The propofol group had significantly (P less than 0.05) faster clinical recovery than the isoflurane group with respect to times to response to commands, eye opening, orientation, ability to stand and void, tolerance to oral fluids, "home-readiness", and recovery of perceptual speed. Patients in the propofol group had significantly less (P less than or equal to 0.05) emesis than the patients given isoflurane. We conclude that in patients undergoing ambulatory surgery propofol infusion is preferable to thiopentone-isoflurane anaesthesia, because it may allow faster discharge home.

Adult↗
PubMed1990

Is the antiemetic effect of the emulsion formulation of propofol due to the lipid emulsion?

The hypothesis that the lipid emulsion of the emulsion formulation of propofol is responsible for the low frequency of nausea, retching, and vomiting after propofol anesthesia was tested. A randomized, prospective, and comparative study was performed to evaluate the antiemetic effect of 10% lipid solution in 60 women, ASA physical status I and II, scheduled for ambulatory laparoscopic procedures. Two groups of patients were studied. Induction of anesthesia (thiopental) and maintenance of anesthesia (enflurane, nitrous oxide) were similar in both groups. At induction the study group received 10% Intralipid (3 mL/min for 20 min). The control group received 5% dextrose in lactated Ringer's solution at the same rate. Other drugs administered during or after anesthesia were similar among the groups. The groups were similar with respect to duration of anesthesia, characteristics of early and intermediate recovery, as well as pain scores in the postanesthesia care unit. There were no differences in the amount of antiemetic medications administered or postoperative nausea, retching, or vomiting when the patients were evaluated objectively by a blinded observer or subjectively by patient self-evaluation. It is concluded that 10% Intralipid, the lipid in the emulsion formulation of propofol, does not possess significant antiemetic effects.

Adult↗
PubMed1990

[Menstrual pneumothorax and pelvic endometriosis. Discussion of pathogenesis].

The authors report a new case of menstrual pneumothorax and pelvic endometriosis which was discovered at this time. In this case (because of the presence of lesions suggesting the condition on thoracotomy) the probable mechanism thought to cause this pneumothorax would be the cyclical shedding of pleural endometriotic lesions. The authors review the characteristics of this unusual syndrome and base their review on an analysis of the hundred cases reported in the literature. They show that there are two theories of pathogenicity classically held. The first is the existence of congenital gaps in the diaphragm which allow air to pass into the pleura during the periods, the other is the possibility of endometriotic pleural lesions damaging the cortex of the lung as they shed their cells during the period.

Adult↗
PubMed1989

Sequence analysis of the Clostridium cellulolyticum endoglucanase-A-encoding gene, celCCA.

The nucleotide sequence of a Clostridium cellulolyticum endo-beta-1,4- glucanase (EGCCA)-encoding gene (celCCA) and its flanking regions, was determined. An open reading frame (ORF) of 1425 bp was found, encoding a protein of 475 amino acids (aa). This ORF began with an ATG start codon and ended with a TAA ochre stop codon. The N-terminal region of the EGCCA protein resembled a typical signal sequence of a Gram-positive bacterial extracellular protein. A putative signal peptidase cleavage site was determined. EGCCA, without a signal peptide, was found to be composed of more than 35% hydrophobic aa and to have an Mr of 50715. Comparison of the encoded sequence with other known cellulase sequences showed the existence of various kinds of aa sequence homologies. First, a strong homology was found between the C-terminal region of EGCCA, containing a reiterated stretch of 24 aa, and the conserved reiterated region previously found to exist in four Clostridium thermocellum endoglucanases and one xylanase from the same organism. This region was suspected of playing a role in organizing the cellulosome complex. Second, an extensive homology was found between EGCCA and the N-terminal region of the large endoglucanase, EGE, from C. thermocellum, which suggests that they may have a common ancestral gene. Third, a region, which extended for 21 aa residues beginning at aa + 127, was found to be homologous with regions of cellulases belonging to Bacilli, Clostridia and Erwinia chrysanthemi.

Amino Acid Sequence↗