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Biomedical subjects

C Picard

Publications and source records attributed to C Picard.

At least 19 recordsLinked to original sources

[Multifocal infection due to Mycobacterium intracellulare: first case of interferon gamma receptor partial dominant deficiency in tropical French territory].

Nontuberculous mycobacterial infections are rare in immunocompetent children, and usually present as adenitis. We report a case of a 6-year-old girl with a multifocal chronic osteomyelitis and pulmonary localisation due to Mycobacterium intracellulare associated with an autosomal dominant mutation of interferon gamma receptor 1 gene (INFGR1) leading to a syndrome of mendelian predisposition to mycobacteria infections by partial deficiency of intracellular signalisation of gamma interferon. This child has been cured with anti-mycobacteria drugs and gamma interferon. This report focus on the importance of looking for a susceptibility of the host to infectious diseases, which can lead to a specific treatment. As far as we know, this is the first case described in a tropical area.

Child↗

A gene responsible for Ghosal hemato-diaphyseal dysplasia maps to chromosome 7q33-34.

Ghosal hemato-diaphyseal dysplasia is a rare autosomal recessive disorder characterized by a progressive sclerosing diaphyseal dysplasia and refractory anemia. The pathogenesis and genetic bases of this syndrome remain hitherto unknown. We have performed a genome wide search in two inbred families originating from Algeria and Tunisia. Here, we report on the mapping of a disease gene to chromosome 7q33-34 (Zmax = 4.21 at theta = 0 at locus D7S2513) in a 3.4 Mb defined by loci D7S2560 and AC091742. Ongoing studies will hopefully lead to identification of the disease-causing gene.

Adult↗

Quantification of mixed chimerism by real time PCR on whole blood-impregnated FTA cards.

This study has investigated quantification of chimerism in sex-mismatched transplantations by quantitative real time PCR (RQ-PCR) using FTA paper for blood sampling. First, we demonstrate that the quantification of DNA from EDTA-blood which has been deposit on FTA card is accurate and reproducible. Secondly, we show that fraction of recipient cells detected by RQ-PCR was concordant between the FTA and salting-out method, reference DNA extraction method. Furthermore, the sensitivity of detection of recipient cells is relatively similar with the two methods. Our results show that this innovative method can be used for MC assessment by RQ-PCR.

Chimerism↗

Allogeneic stem cell transplantation improves the outcome of adults with t(1;19)/E2A-PBX1 and t(4;11)/MLL-AF4 positive B-cell acute lymphoblastic leukemia: results of the prospective multicenter LALA-94 study.

Adult patients with acute lymphoblastic leukemia (ALL) and t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4 have a poor outcome. We have evaluated the impact of an intensified post-remission therapy using a high-dose chemotherapy course followed by allogeneic or autologous SCT on the outcome of 58 patients with t(1;19)/E2A-PBX1 (E2A group, n=24) or t(4;11)/MLL-AF4 (MLL group, n=34) treated in the LALA-94 multicenter prospective study. Patients in the MLL group had higher WBC counts and more frequent DIC. CR rates achieved by MLL and E2A groups were similar to other B-cell ALL (87, 82 and 86% respectively). While in CR, patients with a donor were assigned to alloSCT (n=22), the remaining patients with were randomized between autoSCT (n=15) or chemotherapy (n=8). Five-year overall survival was 31 and 45% for E2A and MLL groups, respectively. In both groups, DFS was higher in the alloSCT arm as compared to autoSCT and chemotherapy arms. The results of this study show that chemotherapy intensification did not overcome the poor prognosis of adults with t(1;19)/E2A-PBX1. Allogeneic SCT should thus be offered in first CR to patients with t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4. New therapeutic approaches are needed for patients without donor.

Adolescent↗

[Simultaneous detection by multiplex PCR of atypical bacterial pathogens involved in infections of respiratory tract. Is it useful for the microbiological diagnosis of respiratory infections].

The aim was to evaluate the "strategical place" of the new commercial test Chlamylege (Argene-Biosoft-France) which allows the simultaneous detection in respiratory samples of Chlamydophila pneumoniae, Mycoplasma pneumoniae and most Legionella species using a PCR multiplex. 41 patients with an atypical pneumonia were included, all standard procedures of diagnosis were done and in addition the chamylege test. A pathogen was identified in 12 patients, an other microorganisms than the 3 targeted by our study was found in 8 patients. 4 positive PCR were obtained, 3 with M. pneumoniae and 1 with Legionella pneumophila 1. That means that for 29 patients no aetiology was found. Among them 23 clearly improved under antibiotic treatment. Though that PCR multiplex is an attractive test, easy to perform, sensitive, specific and convenient, we need further studies to approach the place of this PCR test in the diagnosis of multifaceted atypical pneumonia. We also need to know if the cost associated with the microbiological diagnosis (culture, serology, immunofluorescence, urinary antigen test, PCR...) for atypical pneumonia worth value? An algorithm as to be drawn to determine the value of intensive microbiological investigation. An other point to discuss, may be this kind of rapid and multiplex PCR technique could lead to spare the use of some antibiotics.

Atypical Bacterial Forms↗

[Genetic predisposition and children infectious disease].

The classic primary immunodeficiencies confer predisposition to multiple infectious diseases. However since ten years severe pediatric infections which were idiopathic have now molecular explanation. Indeed, defects in several genes confer a predisposition to infection with specific pathogenes in otherwise healthy individuals. These children present a new kind of hereditary immunodeficiency with severe and/or recurrent infections caused by only one microorganisms family, in opposition of others patients with "classic" primary immunodeficiency.

Child↗

Description of an adenovirus A31 outbreak in a paediatric haematology unit.

Adenovirus infections result in significant morbidity and mortality in allogeneic haematopoietic stem cell transplanted (hSCT) children. Adenovirus from species C and B account for more than 90% of adenoviruses recovered after hSCT. However, infections due to adenovirus A31 have been increasingly reported in recent years. Between April 2002 and April 2005, blood samples obtained every 2 weeks from 58 hSCT children were screened for adenovirus species A to C by quantitative real-time PCR. Phylogenetic analysis was realized after amplification and sequencing of the entire hexon gene. Fifteen cases of adenovirus infection with viraemia were recovered during this 3 years period. During spring/summer 2003, seven cases occurred and were due to an adenovirus species A. Phylogenetic analysis of the seven strains showed that they belonged to the A31 genotype and shared 100% homology. Clinical features of the seven HSCT children with A31 adenovirus viraemia are described. We describe here an epidemic spread of adenovirus genotype A31 in a paediatric haematology unit. Timing, location and hexon gene genotyping results highly suggested a nosocomial origin to this epidemic. The burden of adenovirus A31 infection needs to be further assessed in this context.

Adenovirus Infections, Human↗

Distribution of killer-cell immunoglobulin-like receptor (KIR) in Comoros and Southeast France.

Killer-cell immunoglobulin-like receptors (KIRs) expressed by natural killer cells are cell surface molecules able to recognize groups of HLA class I alleles. The number and distribution of KIR genes vary among individuals and populations. The aim of this study is to analyse the KIR gene content in a Comorian population in order to investigate genetic relationships with other populations and to reconstruct past migration events. The Comorian population consisted of 54 unrelated immigrants living in France and a control population consisted of 38 individuals from Southeast France. We investigated the presence or absence of 15 KIR genes, two pseudogenes expressed and non-expressed forms of KIR2DL5 and the two major subtype full-length and deleted forms of KIR2DS4. All individuals were typed positive for the framework genes, i.e. KIR2DL4, KIR3DL2 and KIR3DL3, and the two pseudogenes KIR3DP1 and KIR2DP1. The frequencies of full-length KIR2DS4 (*00101/00102/002) were lower in the French population (F = 29%) than in the Comorian population (F = 72%) (P(c) < 0.05). No significant differences were found for other KIR genes. A total of 11 genotypes were identified in the Southeast French population and 22 genotypes in the Comorian population. The most common genotype (2DL1, 2DL3, 2DL4, 3DL1, 3DL2, 3DL3 and 2DS4) accounted for 41% in the Comorian population and 34% in the Southeast French population. Principal component analysis using KIR gene data from 20 populations was performed to determine genetic differences and relations between populations. The Comorian population exhibited closest kinship with Africans and Asians. As KIR gene content is heterogeneous among ethnic groups, it can probably be used to assess the genetic relationships among populations from different geographic areas.

Comoros↗

[Immune mediated intra-alveolar haemorrhage in the adult].

INTRODUCTION: The diagnosis of diffuse intra-alveolar haemorrhage (DAH) is suggested by the combination of haemoptysis, anaemia and pulmonary infiltrates. Broncho-alveolar lavage produces macroscopically haemorrhagic fluid and/or haemosiderin laden macrophages. The diagnostic approach should allow distinction between immune mediated and other causes on account of the therapeutic implications. BACKGROUND: The main immunological causes are small and medium vessel vasculitis (Wegener's granulomatosis, microscopic polyangeitis), lupus and Goodpasture's syndrome. Other immune disorders are only rarely involved. The association of DAH with an acute glomerulonephritis, indicating the pulmonary-renal syndrome, extra-thoracic involvement and immunological abnormalities suggest an immune aetiology. Immunosuppressant treatment should be started as soon as possible with corticosteroids often combined with intravenous cyclophosphamide. Plasmapharesis is indicated for Goodpasture's syndrome and poorly responding lupus. Aggravating factors such as hypervolaemia and disorders of haemostasis should be searched for and treated. Hospital mortality is close to 20%. VIEWPOINT AND CONCLUSION: Immune mediated DAH is a disorder whose rarity justifies the establishment of a national registry with the aim of developing standardised diagnostic and therapeutic strategies.

Adult↗

Review article: bifidobacteria as probiotic agents -- physiological effects and clinical benefits.

Bifidobacteria, naturally present in the dominant colonic microbiota, represent up to 25% of the cultivable faecal bacteria in adults and 80% in infants. As probiotic agents, bifidobacteria have been studied for their efficacy in the prevention and treatment of a broad spectrum of animal and/or human gastrointestinal disorders, such as colonic transit disorders, intestinal infections, and colonic adenomas and cancer. The aim of this review is to focus on the gastrointestinal effects of bifidobacteria as probiotic agents in animal models and man. The traditional use of bifidobacteria in fermented dairy products and the GRAS ('Generally Recognised As Safe') status of certain strains attest to their safety. Some strains, especially Bifidobacterium animalis strain DN-173 010 which has long been used in fermented dairy products, show high gastrointestinal survival capacity and exhibit probiotic properties in the colon. Bifidobacteria are able to prevent or alleviate infectious diarrhoea through their effects on the immune system and resistance to colonization by pathogens. There is some experimental evidence that certain bifidobacteria may actually protect the host from carcinogenic activity of intestinal flora. Bifidobacteria may exert protective intestinal actions through various mechanisms, and represent promising advances in the fields of prophylaxis and therapy.

Adult↗

Transient familial haemophagocytic lymphohistiocytosis reactivation post-CD34 haematopoietic stem cell transplantation.

Familial haemophagocytic lymphohistiocytosis (FHLH) is a genetic disorder caused by defective lymphocyte cytotoxicity, resulting in impaired lymphocyte homeostasis and macrophage infiltration of solid tissues and bone marrow, with extensive haemophagocytosis. It is invariably fatal unless treated by allogeneic haematopoietic stem cell transplantation (HSCT). In a retrospective analysis of 11 cases of FHLH, transplanted in one centre between January 1999 and December 2003, it was found that host T cell expansion occurred early after HSCT in a setting of a viral infection (cytomegalovirus and Epstein-Barr virus respectively) in two cases who received T cell-depleted HSCT. Transient recurrence of clinical and biological manifestations of FHLH was observed, despite evidence for donor cell engraftment. Secondary development of donor T cells led to stable mixed chimaerism and sustained remission of FHLH. Detection of host-derived T cells soon after HSCT in a patient with FHLH should thus not mistakenly be taken as a manifestation of graft rejection.

Antigens, CD34↗

[Genetic predisposition and susceptibility to mycobacterial infections: the IL-12-IFNgamma axis deficiency].

Since ten years severe pediatric infections which were idiopathic have now molecular explanation, defined new primary immunodeficiencies. These children presented a new kind of hereditary immunodeficiency with severe and/or recurrent infections caused by only one micro-organisms family. Some of these children have mycobacterial infections. Standard immunologic explorations were normal. However, they presented a vulnerability, sometimes lethal caused by Mycobacteria. The goal of this article is to describe the IL-12-IFNgamma axis deficiency (mendelian susceptibility to mycobacterial disease).

Genetic Predisposition to Disease↗

Analysis of drugs and personal care products in French source and drinking waters: the analytical challenge and examples of application.

This paper illustrates the challenge faced by analytical chemists when trying to measure selected compounds representative of various classes of prescription and hospital drugs. Because hundreds of drugs belonging to a wide variety of chemical groups are allowed for use, an array of analytical methods has to be implemented. As an example, as part of the European Poseidon Project, five different methods were required to measure eight drugs and personal care products. These methods are discussed in detail. Examples of application to surface and ground waters from the Paris area are also reported. The antibiotics roxithromycin and sulfamethoxazole were detected for the first time in the Seine River downstream of Paris. The behaviour of the eight target compounds during aquifer recharge and drinking water treatment is described. An incident involving the detection of micrograms per litre levels of the personal care product Galaxolide in a drinking water distribution system is reported. The value of the pharmaceuticals and personal care products selected as potential indicators is also discussed.

Chemistry Techniques, Analytical↗

[Relationship between clinical findings of patients with bullous pemphigoid and antigens recognized by their circulating antibasement membrane zone antibodies].

INTRODUCTION: Clinical features and extent of bullous pemphigoid lesions differed widely among patients. The pathogenic role of anti-BPAG2 antibodies has been recently demonstrated. The aim of this study was to analyze the relationship between clinical features of bullous pemphigoid patients and the antigens recognized by their serum. PATIENTS AND METHODS: One hundred and twelve bullous pemphigoid patients were included in this prospective multicenter study. Inclusion criteria were the following: 1) diagnosis of bullous pemphigoid established on the presence of 3 of the 4 clinical features of bullous pemphigoid, histological picture of bullous pemphigoid and positive direct immunofluorescence; 2) serum available for immunoblotting studies. The clinical and biological findings were prospectively recorded on standard forms. Sera were collected and analyzed using indirect immunofluorescence and immunoblotting on human epidermal extracts. RESULTS: Analysis of patient's clinical features depending on the antigens recognized by their serum showed that patients whose serum contained anti-BPAG1 antibodies had more frequently pruritus, blisters on the lower limbs and a positive indirect immunofluorescence. Patients whose serum contained anti-BPAG2 antibodies had blisters more frequently localized on the head, and a more frequently negative indirect immunofluorescence. Patients whose serum was negative by immunoblotting had less frequently urticarial and/or eczematous lesions, bullae less frequently localized on the lower part of the trunk, abdomen and lower limbs, lower eosinophilia and a more frequently negative indirect immunofluorescence. CONCLUSION: Patients with circulating anti-BPAG1 antibodies exhibited the most typical, clinical and biological features of bullous pemphigoid.

Aged↗