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J M Garnier

Publications and source records attributed to J M Garnier.

At least 37 records · Page 2Linked to original sources
PubMed2001

Genomic structure and chromosomal mapping of the gene coding for ICBP90, a protein involved in the regulation of the topoisomerase IIalpha gene expression.

We have recently identified a novel CCAAT box binding protein (ICBP90) involved in the regulation of topoisomerase IIalpha gene expression. We have observed that it is expressed in non-tumoral proliferating human lung fibroblast cells whereas in HeLa cells, a tumoral cell line, ICBP90 was still present even when cells were at confluence. In the present study, we have determined the ICBP90 gene structure by screening of a human placenta genomic library and PCR analysis. We report that the ICBP90 gene spans about 35.8 kb and contains six coding exons named A to F. In the 5' upstream sequence of the region containing the coding exons, two additional exons (I and II) were found. Additionally, an internal splicing site was found in exon A. A promoter region, including three putative Sp1 binding sites between exons I and A, was identified by transient transfection. Northern blot analysis of several cancer cell lines revealed the existence of two ICBP90 mRNA species of 5.1 and 4.3 kb that are transcribed from the gene. The relative amounts of these mRNAs depended on the cell type. In MOLT-4 cells and Burkitt's lymphoma Raji cells, the 4.3 kb or the 5.1 kb transcripts were mainly observed, respectively. In other cell lines, such as HL-60 cells, chronic myelogenous leukaemia K-562, lung carcinoma A549, HeLa or colorectal SW480, both 4.3 and 5.1 kb forms of ICBP90 mRNA could be detected. Interestingly, western blot analysis showed several ICBP90 protein bands in HeLa but only a single band in MOLT-4 cell extracts. Taken together our results are consistent with the ICBP90 gene exhibiting alternative splicing and promoter usage in a cell-specific manner.

Alternative Splicing↗
PubMed2001

Diffusion coefficient of DNA molecules during free solution electrophoresis.

The free-draining properties of DNA normally make it impossible to separate nucleic acids by free-flow electrophoresis. However, little is known, either theoretically or experimentally, about the diffusion coefficient of DNA molecules during free-flow electrophoresis. In fact, many authors simply assume that the Nernst-Einstein relation between the mobility and the diffusion coefficient still holds under such conditions. In this paper, we present an experimental study of the diffusion coefficient of both ssDNA and dsDNA molecules during free-flow electrophoresis. Our results unequivocally show that a simplistic use of Nernst-Einstein's relation fails, and that the electric field actually has no effect on the thermal diffusion process. Finally, we compare the dependence of the diffusion coefficient upon DNA molecular size to results obtained previously by other groups and to Zimm's theory.

Algorithms↗
PubMed2001

Kinetics of the adsorption and desorption of radionuclides of Co, Mn, Cs, Fe, Ag and Cd in freshwater systems: experimental and modelling approaches.

The sorption and release kinetics of 54Mn, 58Co, 59Fe, 109Cd, 110mAg and 134Cs by freshwater suspended particles were investigated to better identify the biogeochemical processes involved and to obtain suitable data for improving models describing radionuclide migration in freshwater streams. In order to observe any seasonal variability in the interaction of radionuclides with natural particles, experiments were performed both in winter and in summer during a phytoplanktonic bloom. Two kinetic models are compared in this paper: the "one-step reversible" model, based on the hypothesis that the transfer of radionuclides between water and suspended solids is governed by a reversible reaction, and the "two-successive-step reversible" model, which assumes two distinct types of sites or reactions on the solid phase. The "one-step reversible" model is generally unable to describe properly the exchange kinetics; this result shows that at least two processes are generally involved in radionuclide exchange between water and suspended particles. On the contrary, a model involving the existence of two successive reversible reactions properly simultes both the sorption and release kinetics. The determination of the kinetic coefficients allows quantitative assessment of the relative importance and kinetics of the processes. In particular, it has been shown that, except for Cs and Cd, major fractions of the radionuclides are associated at equilibrium with particulate sites involving strong interactions. The kinetics to reach this equilibrium depend on seasonal conditions, especially for Co and Mn: the transfer of Co and Mn to particulate sites involving strong interactions is much slower in winter. The distribution of the radionuclides between water and particulate sites involving weak interactions also shows seasonal variations for Co, Mn, Fe and Ag: the capacity to associate radionuclides is much higher in summer for Co and Mn, while the inverse tendency is observed for Fe and Ag. For Cs and Cd, no significant seasonal differences were observed.

Adsorption↗
PubMed2001

[Severe cutaneous Streptococcus pyogenes infections in the child: results of a multicenter survey].

UNLABELLED: To assess pediatric cases of severe cutaneous infections due to Streptococcus pyogenes. Since the beginning of 1980, the incidence of cellulitis and necrotizing fasciitis due to S. pyogenes has increased in adults. Serotyping of obtained isolates are in most cases M1, M3 or M5 protein. PATIENTS AND METHOD: A retrospective (1990-2000) survey was carried out in pediatric hospital centers. RESULTS: Three cases of necrotizing fasciitis and 15 of cellulitis were observed. In 30% of the cases, vancella lesions were associated; in the other cases, minor wounds were the site of the infection. Bacteriologic diagnosis was made by local samples in 14 cases; blood cultures were positive in four cases. In 11 cases, initial intravenous treatment consisted of third generation cephalosporin, in six cases of penicillin M or G and in one case of fusidic acid. In the second time, penicillin M was perfused in the majority of the cases. Mean duration of intravenous antibiotics perfusion was 15 days. There were no sequelae or death in this survey. CONCLUSIONS: Despite this study had limited epidemiological characteristics, it confirms that these two infections are rare. The frequency is probably underestimated, due to the difficulty in performing a diagnosis. The major site of infection was the varicella lesion. These two infections are so similar that it is frequent to mistake one infection for the other. Nonsteroidal anti-inflammatory drugs and site of infections did not influence prognosis. The treatment of cellulitis is penicillinotherapy whereas in necrotizing fasciitis early major surgery is often correlated with the rate of survival.

Cellulitis↗
PubMed2001

The nucle(ol)ar Tif6p and Efl1p are required for a late cytoplasmic step of ribosome synthesis.

Deletion of elongation factor-like 1 (Efl1p), a cytoplasmic GTPase homologous to the ribosomal translocases EF-G/EF-2, results in nucle(ol)ar pre-rRNA processing and pre-60S subunits export defects. Efl1p interacts genetically with Tif6p, a nucle(ol)ar protein stably associated with pre-60S subunits and required for their synthesis and nuclear exit. In the absence of Efl1p, 50% of Tif6p is relocated to the cytoplasm. In vitro, the GTPase activity of Efl1p is stimulated by 60S, and Efl1p promotes the dissociation of Tif6p-60S complexes. We propose that Tif6p binds to the pre-60S subunits in the nucle(ol)us and escorts them to the cytoplasm where the GTPase activity of Efl1p triggers a late structural rearrangement, which facilitates the release of Tif6p and its recycling to the nucle(ol)us.

Biological Transport↗
PubMed2001

Functional and structural characterization of the insertion region in the ligand binding domain of the vitamin D nuclear receptor.

Vitamin D nuclear receptor mediates the genomic actions of the active form of vitamin D, 1,25(OH)2D3. This hormone is involved in calcium and phosphate metabolism and cell differentiation. Compared to other nuclear receptors, VDR presents a large insertion region at the N-terminal part of the ligand binding domain between helices H1 and H3, encoded by an additional exon. This region is poorly conserved in VDR in different species and is not well ordered as observed by secondary structure prediction. We engineered a VDR ligand binding domain mutant by removing this insertion region. Here we report its biochemical and biophysical characterization. The mutant protein exhibits the same ligand binding, dimerization with retinoid X receptor and transactivation properties as the wild-type VDR, suggesting that the insertion region does not affect these main functions. Solution studies by small angle X-ray scattering shows that the conformation in solution of the VDR mutant is similar to that observed in the crystal and that the insertion region in the VDR wild-type is not well ordered.

Amino Acid Sequence↗
PubMed2001

[Which prophylaxis for the travelling child?].

Protection against malaria can never be totally effective: chemoprophylaxis may not prevent infection with multidrug-resistant Plasmodium. Drug tolerance may vary. Antimalarial drugs are often not well adapted for infants. Mechanical prophylaxis is essential in childhood: devices as insecticide impregnated bednets or repellents are the most efficient protection against mosquito bites and in fine against infection.

Antimalarials↗
PubMed2000

MEFV mutations in Behçet's disease.

Familial Mediterranean fever (FMF) and Behçet's disease (BD), both inflammatory diseases, are highly prevalent in the Middle Eastern and Mediterranean populations. FMF is a Mendelian autosomic recessive disease linked to MEFV, a gene of unknown function. BD in contrast is a polyfactorial disease associated with the major histocompatibility complex. Because FMF and BD have epidemiological similarities, we asked whether the FMF gene was implicated in BD. We screened for the common MEFV mutations a cohort of 114 chromosomes from definite BD patients [meeting the criteria of the International study group] and probable cases [meeting at least two of these criteria]. We screened in parallel an ethnically matched cohort of FMF and control chromosomes. The M694V, V726A and E148Q mutations tended to be more frequent in definite BD (2.6%, 2.6%, and 5.2%, respectively) than in controls (0%, 0%, and 2.2%). The P706 polymorphism was found in 10.5% of the probable BD chromosomes, but in only 1.6% of the controls (p=0.01). Because some MEFV mutations were more frequent in BD than in controls, we suggest that they may act as additional susceptibility factors in BD.

Africa, Northern↗
PubMed2000

[Childhood visceral leishmaniasis in Provence].

Fifty-nine cases of children with visceral leishmaniasis were retrospectively studied in a survey of hospital records in the Provence region of South France concerning a 15 years period (1981 to 1997). None of the children was immunocompromised. The mean age was 31 months but 10 children were younger than one year. The male/female ratio was 0.73. Fever and splenomegaly were present in 90% and 100% of the cases respectively. Anemia, leukopenia and thrombocytopenia were commonly observed. A medullogram was systematically performed, but direct microscopic examination of the bone marrow identified Leishmania in only 78% of the cases. In these patients, specific serology and genomic amplification using polymerase chain reaction were useful tools for the diagnosis. All patients were initially treated with meglumine antimonate (Glucantime). Twenty-six (44%) receiving the drug experienced at least one adverse event during treatment. Treatment failure occurred in 6 children (10%), who were subsequently cured with liposomal amphotericin B. Three additional children were treated with liposomal amphotericin B. All the children were finally cured and no death was observed. Pediatric visceral leishmaniasis is an uncommon disease in the endemic area of South France. Resistance to antimonial therapy occurs in children as well as in adults. Liposomal amphotericin B appears as an effective therapy for visceral leishmaniasis in children and could be used as a first-line treatment.

Adolescent↗
PubMed2000

[Hypoxic-ischemic encephalopathy in the full-term newborn. Contribution of electroencephalography and MRI or computed tomography to its prognostic evaluation. Apropos of 26 cases].

OBJECTIVES: Perinatal asphyxia complicated by hypoxic ischemic brain injury still remains the source of neurological lesions often serious and definitive. A major aim of neonatologists is to appreciate the severity of the hypoxic ischemic brain injury in the first days of life and to evaluate the forecast. The purpose of this work is to establish a relation between clinical signs, EEG, neuroimaging (MRI and CTS) and neuro-development. MATERIALS AND METHODS: 26 neonates from paediatric resuscitation unit (Hospital North, Marseille) were enrolled in a retrospective study since February 1994 to December 1997. All the newborns had at least one anamnestic criteria of perinatal asphyxia, an early electroencephalogram in the first two days of life and another between the third and the seventh day of life, and neuroimaging in the first 15 days of life: CTS in five cases and MRI in 21 cases. RESULTS: There was a good electro-clinic (P: 0.01) and prognostic (P: 0.03) correlation in patients within stage 3 of the "Sarnat classification". In the stage 2, the EEG did not provide valuable information about severity of the injury, and neuroimaging (especially MRI) allowed better prognosis. Diffuse brain injury or lesions of basal ganglia in MRI were associated, independently of clinical settings and EEG tracings, with a poor neurodevelopmental outcome (P: 0.02). The MRI was diagnostic in four cases of congenital encephalopathy complicated with neonatal suffering. CONCLUSION: Our study confirms the interest of the association of clinical settings, EEG tracings and MRI in the diagnosis and the prognostic of the hypoxic-ischemic encephalopathy in term neonate.

Disease Progression↗
PubMed2000

Phenotype-genotype correlation in 91 patients with familial Mediterranean fever reveals a high frequency of cutaneomucous features.

OBJECTIVES: To describe the clinical manifestations of familial Mediterranean fever (FMF) in 91 patients from 47 families and provide data from the genetic study. P:atients and methods. We conducted a retrospective chart review of 91 patients (including 83 children aged <15 yr) from 47 families through a questionnaire and a specific database. The genetic analysis included complete screening of known mutations of the MEFV gene on chromosome 16p13.3. A positive diagnosis required at least two mutations, one on each chromosome. RESULTS: Our panel included 52 females and 39 males, with a mean age of 7.27 yr. Of the 47 families, 31 were non-Ashkenazi Jews, 10 were Armenians and six were from other ethnic groups. Clinical features included fever (100%), peritonitis (86%), pleuritis (56%), arthritis (34%) and myalgias (27%). We observed a high rate of cutaneous manifestations (47%); erythema, oedema and recurrent oral ulcers were the most frequent. Phenotype-genotype correlations showed a significant association of M694V homozygosity with earlier age of onset (P: = 0.044), fever >39 degrees C (P: = 0. 002), pleural crisis (P: = 0.0044), splenomegaly (P: = 0.0005) and arthritis (P: = 0.001). Associations with mucocutaneous features were as follows: erysipelas-like erythema (P: = 0.012), oedema (P: = 0.61, not significant) and oral ulcers (P: = 0.45, not significant). CONCLUSION: New phenotype-genotype correlations emerged from our study: homozygosity for the M694V mutation was associated with intensity of fever, splenomegaly and with erysipelas-like erythema. Apart from erysipelas-like erythema, no significant association was found between other cutaneous features and the genotype.

Adolescent↗
PubMed1999

[Congenital toxoplasmosis and cerebral involvement inspite of prenatal treatment].

BACKGROUND: Maternal toxoplasmosis seroconversion during the first trimester of pregnancy raises an important risk of toxoplasmic fetopathy. CASE REPORT: Primary toxoplasmosis was identified between 9 and 17 weeks of gestation. PCR analysis of the amniotic fluid confirmed fetal infection. The mother was given a sulfadoxine-piremythamine combination and monthly ultrasonographic surveillance was initiated. At birth, the female infant was found to have diffuse cortical lesions and a chorioretinitis compatible with toxoplasmic fetopathy. She was given sulfadoxine-piremythamine. At 2 years, the clinical and neuroradiological course has been favorable. CONCLUSION: Despite antenatal and postnatal treatment and despite ultrasonographic surveillance, it is difficult to predict the course of congenital toxoplasmosis. This case illustrates the importance of informing parents of the risk and the requirement for careful follow-up after antenatal diagnosis of first-trimester toxoplasmosis.

Adult↗
PubMed1999

[Mediterranean visceral leishmaniasis: physiopathology].

INFANTILE LEISHMANIASIS: The protozoan parasites of the genus Leishmania are the causal agent of various diseases ranging from cutaneous lesions to fatal systemic diseases. In southern France, Leishmania infantum is an endemic species recognized as the causal agent of infantile leishmaniasis (Mediterranean visceral leishmaniasis). Little is known about the pathophysiology of the disease in humans, but models in mice may provide a new approach. INSECT VECTOR: Leishmania infantum are carried by sand flies. Antigenic modifications of the promastigote forms occur in these insects modifying lipophyosphoglycan (LPG) or glyocprotein gp63. Salivary gland lysates from the sand flies also enhance Leishmania infectivity. HUMAN INFESTATION: In humans, LPG and gp63 play a role in complement fixation, cell adhesion and resistance to complement-mediated lysis. Macrophage expression of class I and II major histocompatibility complex antigens is suppressed. T cells and interferon gamma are very important keys in the control of the parasite infection.

Adolescent↗
PubMed1999

[Treatment of infantile visceral leishmaniasis].

Visceral leishmaniasis is an endemic disease in the Mediterranean Basin. Children are one of the targets of the infection. Treatment usually requires parenteral injections of pentavalent antimony (Glucantime or Pentostam), but the high frequency of adverse events and the occurrence of primary or secondary resistance cases limit the use of these medications. Diamidines (Pentacarinat) or amphotericin B derivatives are alternatives to antimony. Unfortunately, pharmacokinetics and optimal dosage of diamidines are not well-known, and numerous adverse events are described. Liposomal preparations of amphotericin B enhance its efficiency and tolerance, and the duration of treatment may be reduced to 5 days. Moreover, primary resistance to amphotericin B is not described in immunocompetent children. Allopurinol associated with antimony seems no more efficient than antimony alone. Aminosidine is not evaluated.

Amphotericin B↗