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C Lecomte

Publications and source records attributed to C Lecomte.

At least 73 records · Page 4Linked to original sources
PubMed1993

Nucleotide sequence of the bovine viral diarrhoea virus Osloss strain: comparison with related viruses and identification of specific DNA probes in the 5' untranslated region.

The nucleotide sequence of the cytopathic Osloss isolate of bovine viral diarrhoea virus (BVDV) was deduced from overlapping cDNA clones and from PCR products. The Osloss genome is an RNA molecule of positive polarity containing 12,480 nucleotides and having the capacity to code for a polyprotein of 3975 amino acids. The presence of the previously described internal stop codon in this viral sequence was disproved after direct sequencing of the appropriate PCR-amplified fragment. Except for the previously reported insertion of a sequence coding for a ubiquitin-like protein, the viral genome shares great similarity with those of three other strains of the pestivirus genus. Computer-assisted sequence analyses and comparisons of known pestiviral genomic sequences led us to identify selected PCR primers in the 5' untranslated region. These primers were used successfully to amplify 18 distinct pestivirus isolates and potential DNA probes were noted from the deduced sequences. The possible use of a well conserved 26 base fragment as a diagnostic probe was confirmed in hybridization experiments. The 5' untranslated region was further studied and compared with those of other members of the Flaviviridae family, which includes the flaviviruses and the hepatitis C virus group. These sequence analyses support the possibility of discrimination amongst the closely related ruminant pestiviruses, border disease virus and BVDV.

Amino Acid Sequence↗
PubMed1993

Five hours to identify immunotolerant cattle, persistently infected with bovine virus diarrhoea virus.

Detection of animals which are persistently-infected with bovine virus diarrhoea virus (BVDV) is of prime importance in the control of pestivirus infections in cattle, as these animals constitute the main reservoir of the virus. Identification of such animals can be readily performed using crude whole blood samples with a sandwich enzyme-linked immunosorbent assay (ELISA) requiring only approximately five hours. This ELISA uses a combination of monoclonal antibodies as the capture agent and an immunological amplification step of the specific signal for detecting the non-structural 80/120 kDa protein of BVDV. The degree of correlation between this ELISA and virus isolation as the reference method is 100% for animals older than six months.

Animals↗
PubMed1992

Crystal chemistry of Mg2P2O7.nH2O, n = 0, 2 and 6: magnesium-oxygen coordination and pyrophosphate ligation and conformation.

The crystal structure of the hexahydrate has been determined and is compared with the known structures of the dihydrate and two forms of the anhydrous compound. Comparisons among the structures provide some insight as to the structural role of Mg2+ as a cofactor in the ATP-ADP hydrolysis reactions of bioenergetics. Crystal data for dimagnesium pyrophosphate hexahydrate: Mg2P2O7.6H2O, M(r) = 330.66, monoclinic, P2(1)/n, a = 7.189 (2), b = 18.309 (8), c = 7.665 (5) A, beta = 92.360 (14) degrees, V = 1008.1 A3, Z = 4, Dx = 2.18 mg mm-3, F(000) = 680, mu = 0.609 mm-1 for lambda(Mo K alpha) = 0.7107 A. R(magnitude of F) = 0.047 for 937 data.

Adenosine Triphosphate↗
PubMed1992

[Primary amenorrhea revealing micropolycystic ovary syndrome].

Nine patients with polycystic ovary syndrome revealed by primary amenorrhea were studied clinically, biochemically and ultrasonographically. One of them had excess weight, four had hirsutism and five acne. Testosterone and delta 4-androstenedione levels were high in all patients. Luteinizing hormone (LH) basal levels were increased in five patients. Basal values of follicle-stimulating hormone (FSH) remained within normal range. The LH to FSH ratio was elevated (over 2) in six patients. The LSH response to gonadotropin-releasing hormone (GnRH) was explosive in all patients. Ultrasonography showed that three out of five patients had enlarged ovaries with multiple follicles not exceeding 8 mm. Following treatment, two patients had children after ovulation was induced with clomiphene citrate, one patient became pregnant spontaneously but thereafter opted for voluntary interruption; two patients are still on ovulation-inducing therapy; four patients still have contraception. These results indicate the clinical heterogeneity and the diagnostic problems that surround this uncommon form of a frequently observed disease.

Adolescent↗
PubMed1991

Electron distributions in peptides and related molecules. 1. An experimental and theoretical study of N-acetyl-L-tryptophan methylamide.

The thermal vibrations and electron density of N-Ac-L-Trp-NHMe have been analyzed using single-crystal X-ray diffraction data measured at 103 K with Mo K alpha radiation to a resolution corresponding to (sin theta max)/ lambda = 1.17 A-1. Measurements of 10,527 reflections gave 4913 unique data [R(int)(magnitude of F2) = 0.019] of which 2641 had I greater than 3 sigma (I). A multipolar atomic density model was fitted [R(magnitude of F) = 0.028] in order to calculate phases for the crystal structure factors and map the valence-electron distribution. The phase problem for determining deformation densities by Fourier synthesis for noncentrosymmetric crystals is discussed. The experimental density agrees well with the theoretical density from an ab initio SCF molecular wave function calculated at the crystallographic molecular geometry with a split-valence basis set. Both the experimental and theoretical analyses confirm that the electron distribution is the same in the two different peptide groups in the molecule. Crystal data: C14H17N3O2, Mr = 259.31, orthorhombic, P2(1)2(1)2(1), Z = 4, F(000) = 522 e from 295 to 103 K; at 295 K, a = 8.152(2), b = 11.170 (2), c = 15.068 (3) A, V = 1372 A3, Dx = 1.26 mg mm-3; at 103 K, a = 8.209 (3), b = 11.016 (2), c = 14.760 (4) A, V = 1135 A3, Dx = 1.29 mg mm-3, mu = 0.083 mm-1 for lambda = 0.7107 A.

Chemical Phenomena↗
PubMed1991

Identification and production of pestivirus proteins for diagnostic and vaccination purposes.

Using a panel of monoclonal antibodies (MAbs) previously characterized by seroneutralization, immunofluorescence and radioimmunoprecipitation, we have identified Pestivirus proteins useful for diagnostic purposes from the cytopathic Osloss isolate of bovine viral diarrhea virus (BVDV). Proteins that should be useful for vaccination have also been analysed. Cell-free translation of RNA from glycoprotein-coding cDNA fragments produced, when synthesized in the presence of canine pancreatic microsomes, two glycosylated proteins that were independently recognized and immunoprecipitated by two distinct classes of neutralizing MAbs. A similar in vitro procedure was carried out on nonstructural protein-coding sequences and allowed to identify a viral translation product that specifically reacted with MAbs directed against the 80 kDA protein of a number of Pestivirus strains. Its positioning within the polyprotein encoded by the viral genome was refined by epitope scanning using synthetic hexameric peptides. This viral antigen was further expressed in E. coli, produced as inclusion bodies and used successfully as an ELISA antigen in both competitive and indirect assays for the detection of BVD antibodies in cattle sera.

Animals↗
PubMed1990

The coding region for the 54-kDa protein of several pestiviruses lacks host insertions but reveals a "zinc finger-like" domain.

We sequenced cDNAs, amplified by the polymerase chain reaction (PCR), which correspond to the carboxy-terminal portion of the 54-kDa protein of various cytopathic (cp) or noncytopathic (ncp) pestiviral strains. Except for the previously described insertions in two cp strains of the bovine viral diarrhea virus (BVDV), we did not find comparable insertions in this gene in eight pestiviral strains. The predicted amino acid sequences of this 54-kDa protein portion contain a conserved cysteine-rich stretch remarkably similar to a "zinc finger-type" binding domain found in many gene-regulatory proteins. Thus, this protein may be involved in the binding to viral RNA.

Amino Acid Sequence↗
PubMed1990

ELISA detection of bovine viral diarrhoea virus specific antibodies using recombinant antigen and monoclonal antibodies.

A panel of monoclonal antibodies was prepared by immunization of BALB/c mice with Moredun (BD) virus strains. These antibodies were characterized by immunofluorescence and seroneutralization against BD, BVD and hog cholera (HC) virus strains, and radioimmunoprecipitation of BVD-infected cells extracts. The MAbs reacting with the majority of the Pestivirus strains recognize the 80 kDa antigen of the BVD cytophathic strains. The 80 kDa antigen of the BVD/Osloss virus strain has been cloned and expressed in E. coli as a fusion protein with beta-galactosidase. The fusion protein has been purified from inclusion bodies and used successfully as an antigen for ELISA detection of BVDV specific antibodies in bovine sera. A competitive ELISA using MAbs is more specific than a direct assay. These results compare well with the ones obtained with antigen extracted from BVDV-infected cells.

Animals↗
PubMed1988

Serial study of T-lymphocyte subsets in women during very early pregnancy.

The aim of this serial study was to define variations in T-lymphocyte populations during the first weeks of pregnancy. Results obtained with 14 women pregnant after artificial insemination show that the CD4+ population decreased significantly as soon as the fourth week. This decrease was concomitant with the HCG peak and could be compatible with certain immunological mechanisms participating in tolerance to the fetal graft.

Adult↗
PubMed1988

[An in vitro study, in the human, of the relation between epididymal spermatozoa and the zona pellucida].

The ability of non capacitated human spermatozoa recovered from the caput, corpus and cauda epididymis, to bind the isologous or heterologous (rat) zona pellucida has been investigated. Experiments were performed with cold immobilized spermatozoa to avoid differences resulting from motility into the epididymis. Comparison with similar investigations in the ram (works and review of Fournier-Delpech and Courot, 1987) lead to conclude that human spermatozoa are: 1) able to bind to the human zona in the proximal epididymis; 2) unable to recognize heterologous zona at any level of the epididymis. From this, a strict species-specificity of the sperm-zona interactions exists in the proximal epididymis, in the human. By contrast, in the ram, sperm-zona binding develops in the epididymis iso- or hetero-specifically. Restricted species specificity appears in the ejaculate only. Data are in agreement with species specificity of gametes interactions in the human (Bedford, 1977). Such results could contribute to explain in vitro or in vivo fertilization with sperm originating from the middle epididymis (Temple-Smith et al., 1985; Soychsman and Bedford, 1986).

Adolescent↗
PubMed1987

A radioprotector: cysteamine, inhibits oxygen transport in lipidic membranes.

Spin labeling techniques make possible the observation of oxygen diffusion or concentrations in phospholipid membranes. In such a system, cysteamine, depending upon the molecular cysteamine/DPPC ratio and the pH conditions, inhibits oxygen transport, and this result provides an original explanation for cellular hypoxia after cysteamine administration.

Biological Transport↗
PubMed1986

[Use of the mixed antiglobulin reaction (MAR) latex test in routine detection of antisperm agglutinating antibodies in subjects with spontaneous autoagglutination].

A mixed antiglobulin reaction: M.A.R. latex test has been used to detect the presence of either IgG or IgA on the surface of spermatozoa in a selected population with spontaneous agglutination. Positive M.A.R. tests showed a highly significant correlation with the presence of antisperm antibodies in seminal plasma or serum and with sperm penetration in cervical mucus. Autoantibodies against spermatozoa were found in 4.25% of seminal fluid samples.

Autoantibodies↗
PubMed1986

The peroperative management in multiple organ donors: a crucial phase in organ transplantation.

Recent developments in organ transplantation led to the fact that any potential cadaver donor might be considered as a multiple organ donor (MOD). The anesthesiologist's role is to maintain good hemodynamic conditions during the long and complex harvesting procedure, taking into account that in renal cadaver transplantation, donor's stable hemodynamic conditions play a crucial role in the immediate function of the graft. Taking the opportunity of a case of simultaneous liver, pancreas and kidneys procurement in the same cadaver donor performed for the first time in our country, we are reviewing the different phases of the donor peroperative management. This implies a strict control of the systolic blood pressure (SBP) and central venous pressure (CVP). The first step was to maintain the blood volume: during the 3 hours procedure, 5.5 liters of crystalloid, 1.2 liters of colloid and 1 liter of blood were perfused to maintain a CVP higher than 8 mm Hg and a SBP above 110 mm Hg. To obtain the best possible renal and hepatic perfusion, 4 micrograms/kg/min. dopamine is injected continuously, along with 100 mg phenoxybenzamine since the beginning of the operation in order to avoid any local arterial spasm. After heparinization (3 mg/kg 10 minutes prior to clamping), all organs are simultaneously perfused in situ with 3 liters of Euro-Collins solution at 4 degrees C, for cold storage in optimal conditions. The pancreas along with one kidney was transplanted in a diabetic women in preterminal end-stage renal disease: current creatinine (2 months post-transplant) is 1.3 mg/dl and C-peptide is 0.8 pmol/ml. The other kidney was successfully transplanted in another center. The liver graft was implanted in a cirrhotic patient: current bilirubin is 6 mg/dl, S.G.O.T. and S.G.P.T. respectively 50 and 149 U.I.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1983

[Pregnancy and labor after insemination with frozen sperm from a donor].

A total of 168 out of 196 pregnancies that were obtained after A.I.D. have been followed up. Six cases were lost for follow-up (3%). The mean age was 30 years and 65% of the women had their ovulation induced. 130 nullipara were delivered. They were compared with a series of nullipara of the same age group and selected from 300 primiparous pregnancies who delivered in the department in the same year. The abortion rate was 12.5%. 79% of the pregnancies were normal in the 2nd and 3rd trimesters as compared with 83% in the control series. 94% delivered at term as compared with 97% in the control series. 21% of the women had Caesarean section as compared with 19.2% in the control series. The sex ratio was 1.08 as compared with 1.06 in the control series. There was no significant difference between the two series. It does seem, however, that the age factor is the most important factor of all in determining how frequent pathological conditions will be and the number of Caesareans that will have to be carried out. 14% were under 30 years of age as compared with 28.5% who were over 30 years of age, which is a significant difference. These results should be followed up in a larger series.

Abortion, Spontaneous↗
PubMed1982

Therapist expectancies: client gender, and therapist gender, profession, and level of training.

Examined the influence on therapists' expectancies of four variables: Client's gender, therapist's gender, therapist's professional affiliation, and therapist's level of training. A total of 893 counselors, clinical social workers, and clinical psychologists at three training levels (beginning master's student, ending master's student, post-master's professional) completed the Therapist Expectancy Inventory in reference to a male or female client description. Data were analyzed using MANOVA and discriminant function analysis procedures. Significant differences on diagnostic, prognostic, or process dimensions of expectancies were found for the main effects of therapist gender, professional affiliation, and level of training. The client gender effect was not significant. It is concluded that therapists' judgments about the client and their role in counseling are more a function of certain therapist characteristics than client gender.

Adult↗