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M Cornet

Publications and source records attributed to M Cornet.

At least 19 recordsLinked to original sources
PubMed2002

[Mycologic surveillance of the environment for preventive invasive aspergillosis. Proposals for standardization of the methodologies and implementation].

A MAJOR RISK: The infection of immunodepressed patients by Aspergillus-type fungi increases morbidity and mortality, particularly in hematology units or during solid organ transplantation. Although present diagnostic means benefit from the progress over the last years, they remain limited and chemoprophylaxis protocols have still not demonstrated significant efficacy. THE NEED FOR RECOMMENDATIONS: Today, the handling of environmental risks is the only strategy that has proved its efficacy and usefulness. On the basis of administrative recommendations and data from the literature, a multicentric and pluri-disciplinary task force, grouping clinicians, microbiologists and hygienists, has assessed different methods and has proposed recommendations for the standardization and optimization of fungal surveillance of the environment.

Air Microbiology↗
PubMed2002

Modifier genes in haemophilia: their expansion in the human genome.

Mutations in factor VIII and IX genes have a determinant effect on the severity of haemophilia. Modulation of clinical manifestations depends on other genetic factors, including modifier genes. In the context of haemophilia, such genes could be the ones involved in thrombophilia. Factor V Leiden and prothrombin 20210A were studied as possible phenotypic modifiers. Inhibitor development after therapeutic factor replacement depends on the type of mutation and on the genetic factors related to the immune response of each patient. The study of all these variants in haemophiliacs constitutes an important step in prevention, prognosis and therapeutic alternatives of the disease.

Factor VIII↗
PubMed2002

Epidemiology of invasive aspergillosis in France: a six-year multicentric survey in the Greater Paris area.

Invasive aspergillosis is the most prevalent mould infection. An epidemiological surveillance network was set up in 18 teaching hospitals in Paris and the Greater Paris area. Prospective surveillance was conducted between 1994 and 1999. Between 1994 and 1997 cases were categorized as proven or probable aspergillosis and then the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria were used. The authors analysed 621 cases (115 proven, 506 probable). No seasonal variation was found. Haematological disorders (73%) including stem-cell transplantation (36%), solid-organ transplantations (10%) and AIDS (9%) were the main underlying conditions. The crude mortality was 63%. Incidence of IA was 8% (CI(95): 6.5-9.5) in acute myelocytic leukaemia and 6.3% (CI(95): 4.3-8.3) in acute lymphocytic leukaemia. Incidence was 12.8% (CI(95): 10.8-14.8) following allogeneic stem-cell transplantation and 1.1% (CI(95): 0.7-1.5) following autologous stem-cell transplantation. In solid-organ recipients incidence ranged from 11% following heart-lung transplantation and small bowel to 0.4% following kidney transplantation. Incidence in HIV infected patients ranged from 0.02 to 0.13% per annum. This large series confirmed that patients with haematologic disorders and transplantations are the most at risk for IA.

Adolescent↗
PubMed2001

Lactobacillus sakei: recent developments and future prospects.

Lactobacillus sakei is one of the most important bacterial species involved in meat preservation and meat fermentation. In the last fifteen years, numerous studies have focused on this species due to its important role in food microbiology. The present paper reviews current knowledge of this emerging species in the fields of taxonomy, phylogeny and physiology, and metabolism. Recent developments in genetic tools and molecular genetics will also be emphasized to evaluate future prospects.

Food Microbiology↗
PubMed2001

Dermatophyte pseudomycetoma of the scalp: case report and review.

We report the first case of a scalp pseudomycetoma due to Trichophyton schoenleinii in a 15-year-old girl from Senegal. The lesion was not associated with tinea capitis. Long-term antifungal therapy with itraconazole and terbinafine was unsuccessful but a favourable outcome was obtained after surgical removal of the lesion. Between 1973 and 1999, only 12 previous cases of dermatophyte pseudomycetoma of the scalp were reported in the literature. Clinical features and therapeutic outcomes of these cases are reviewed.

Adolescent↗
PubMed1999

Efficacy of prevention by high-efficiency particulate air filtration or laminar airflow against Aspergillus airborne contamination during hospital renovation.

OBJECTIVE: To evaluate efficacy of laminar airflow facilities plus high-efficiency particulate air (HEPA) filtration and HEPA filtration alone in preventing environmental Aspergillus contamination during hospital renovation. To show the usefulness of environmental surveillance to facilitate protection of patients at risk for invasive pulmonary aspergillosis. DESIGN: Prospective sampling of air and surfaces for Aspergillus conidia during 2-year period. SETTING: A hematological department adjacent to building renovation at a university hospital. RESULTS: 1,047 air samples and 1,178 surface samples were collected from January 1996 to December 1997. Significantly more air samples were positive for Aspergillus species during the period of building renovation than during the periods before and after renovation in a unit without a protected air supply adjacent to the building work area (51.5% vs 31.7%; odds ratio [OR], 2.3; 95% confidence interval [CI95], 1.4-3.7; P<.001). A major increase in the frequency of positive air samples was also found in another adjacent unit that was protected with HEPA filtration alone (from 1.8% to 47.5%; OR, 48.9; CI95, 12-229; P<10(-7)). In addition, in this unit, the mean count of Aspergillus conidia in positive air samples increased significantly during construction (4 colony-forming units [CFU]/m3 to 24.7 CFU/m3; P=.04) and the proportion of positive surface samples showed a significant increase during renovation (from 0.4% to 9.7%; OR, 28.3; CI95, 3.4-623; P=10(-4)). However, none of 142 air samples collected during renovation in the area protected with laminar airflow plus HEPA filtration showed Aspergillus conidia. In a unit distant from the building renovation site, the results of air and surface samples were not affected by renovation. CONCLUSION: This study showed a strong association between building renovation and an increase in environmental Aspergillus contamination. Results confirmed the high efficacy of laminar airflow plus HEPA filtration and a high air-change rate. Although filtration with HEPA was effective during normal conditions, it alone was unable to prevent the rise of Aspergillus contamination related to building renovation. This study emphasized the necessity of an environmental survey of airborne contamination related to construction, to facilitate prevention of nosocomial aspergillosis outbreaks. A standardized protocol for aerobiological surveillance is needed.

Air Microbiology↗
PubMed1998

Molecular typing of environmental and patient isolates of Aspergillus fumigatus from various hospital settings.

Fingerprinting of more than 700 clinical and environmental isolates of Aspergillus fumigatus from four differential hospital settings was undertaken with a dispersed repeated DNA sequence. The analysis of the environmental isolates showed that the airborne A. fumigatus population is extremely diverse, with 85% of the strains being represented as a single genotype isolated once. The remaining 15% of the strains were isolated several times and were able to persist for several months in the same hospital environment. No strains were found to be associated with a specific location inside the hospital, and identical strains were isolated from different buildings of the hospital and outdoors. Isolation of the same strain both from patients and from the environment of the same hospital is highly suggestive of a nosocomial infection. The characteristics of the environmental fungal population explains the two main results obtained from the typing of the clinical isolates: (i) the absence of a common strain responsible for an invasive aspergillosis outbreak results from the extreme diversity of the environmental population of A. fumigatus in contact with the patients, and (ii) patients hospitalized in different wards of the same hospital can be infected with the same strain since every patient might inhale the same spore population.

Air Microbiology↗
PubMed1998

Respiratory distress due to tracheal aspergillosis in a severely immunocompromised patient.

A 23-year-old man, intensively treated for acute lymphoblastic leukaemia in relapse and with documented pulmonary aspergillosis, was admitted to the intensive care unit for acute respiratory failure. The diagnosis of invasive tracheal aspergillosis was made by bronchoscopy and biopsy. The lesions consisted of extensive necrotizing bronchitis with transmural and peribronchial extension associated with tracheal and bronchial obstruction due to the presence of pseudomembranes almost entirely composed of fungal hyphae. Despite treatment with amphotericin B and itraconazole, mechanical ventilation and bronchoscopy, the patient died 3 weeks later of massive bleeding.

Adult↗
PubMed1998

Prevalence of and risk factors for anemia in young children in southern Cameroon.

Anemia during childhood remains a major public health challenge in sub-Saharan Africa. To determine the prevalence of and the main risk factors for anemia in young children, we conducted a longitudinal survey in Ebolowa in southern Cameroon. Children were enrolled in two cohorts and followed during a three-year period: the first cohort was composed of 122 children from 0 to 36 months of age and the second cohort was composed of 84 children from 24 to 60 months of age. The two cohorts were followed weekly for symptomatic malaria, monthly for both symptomatic and asymptomatic malaria, and every six months for hematologic data; the children were grouped into six-month age groups. The prevalence of anemia (hemoglobin [Hb] level < 11 g/dl) was the highest in the six-month-old age group (47%) and the age-related evolution clearly showed a decrease in the prevalence from three years of age. Thus, 42% of the children less than three years of age were anemic, while 21% of the children between three and five years of age were anemic. The lowest mean +/- SD Hb content (10.7 +/- 2.1 g/dl) was observed in the six-month-old children and a regular improvement in the Hb level occurred from six months to three years of age. A stabilization was observed at a level of approximately 12 g/dl. At any age, there was no difference in mean Hb levels between children with AS and AA Hb genotypes. Hookworm infection was diagnosed in two children in the study population. Results of a multivariate analysis showed that placental malaria infection was the strongest risk factor for anemia in the six-month-old children (odds ratio [OR] = 3.6; 95% confidence interval [CI] = 1.1-12.3) and was independent of the frequency of parasitemia, parasitemia at the time of Hb measurement, or microcytosis. In the one-year-old age group, microcytosis was a significant factor related to anemia (OR = 2.8, 95% CI = 1-7.8) pointing out the role of iron deficiency at this age. Parasitemia at the time of Hb measurement was significantly associated with anemia in all age groups (except in 54- and 60-month-old groups). Strategies to decrease the prevalence of anemia in young children in southern Cameroon should include chemoprophylaxis for pregnant women, prevention of acquired malaria infection in both pregnancy and infancy, and prevention of nutritional iron deficiency.

Anemia↗
PubMed1997

Isotypic analysis of maternally transmitted Plasmodium falciparum-specific antibodies in Cameroon, and relationship with risk of P. falciparum infection.

In malaria-endemic areas, infants are relatively protected against malaria infection. Such protection is though to be related principally to the transplacental transfer of maternal antibodies. We measured total and Plasmodium falciparum-specific IgG (including subclasses), IgM, and IgE antibodies in 154 paired maternal-cord serum samples from an area of meso- to hyperendemic malaria in South Cameroon. Among peripheral mother blood samples, total IgG and IgM were detected in all samples, IgE in all but two. Plasmodium falciparum-specific IgG were detected in all serum samples, IgM and IgE in > 75% of samples. The prevalence rates of anti-P. falciparum IgG subclasses varied from 75% to 97%. With the exception of P. falciparum-specific IgG, all antibody class and subclass levels were lower in cord blood than in peripheral mother blood. Plasmodium falciparum-specific IgG1 and IgG3 isotypes were transferred to the offspring more often and more efficiently than IgG2 and IgG4. The detection of total and P. falciparum-specific IgM and IgE in some cord serum samples demonstrated that fetuses can mount humoral response against malaria parasites. We also determined whether transplacentally acquired antibodies protect against malaria infection by relating the antibody levels at birth to the risk of acquiring P. falciparum infection during the first 6 months of life. Among various classes and subclasses of P. falciparum-specific antibodies, only IgG2 were related to a decrease in the risk of acquiring a P. falciparum peripheral blood infection from birth to 6 months of age.

Adolescent↗
PubMed1997

Metabolism and toxicity of 2-methylpropene (isobutene)--a review.

2-Methylpropene (MP) or isobutene is a gaseous chemical used on a large scale in the synthetic rubber industry. The present review covers the rather scarce literature on MP with respect to its metabolic fate and toxicity in laboratory animals and humans. It has been shown both in vivo and in vitro that MP is metabolized to the primary metabolite 2-methyl-1,2-epoxypropane (MEP) by rodent and human liver tissue. The formation of this reactive epoxide intermediate is catalyzed by CYP2E1, while epoxide hydrolase and glutathione S-transferase appear to be involved in its inactivation. In rats, the capacity to absorb and metabolize MP is saturable. MP is oxidized to compounds that are mainly excreted in urine. Data indicate that rodents can tolerate low levels of MP without apparent toxicity. The primary metabolite MEP, however, is able to produce genetic damage in both prokaryotic and eukaryotic cells in vitro. MP is thus not toxic per se but elicits metabolic activation to become potentially harmful. Consequently, the balance between formation and detoxification of MEP plays a key role in determining the potential toxicity of the parent compound. Obviously, further research, including repeated exposure toxicity studies, is required before an estimation of the risk for man can be made.

Alkenes↗
PubMed1996

Prediction of myotonic dystrophy clinical severity based on the number of intragenic [CTG]n trinucleotide repeats.

We carried out a genotype-phenotype correlation study, based on clinical findings in 465 patients with myotonic dystrophy (DM), in order to assess [CTG] repeat number as a predictive test of disease severity. Our analysis showed that the DM subtypes defined by strict clinical criteria fall into three different classes with a log-normal distribution. This distribution is useful in predicting the probability of specific DM phenotypes based on triplet [CTG] number. This study demonstrates that measurement of triplet expansions in patients' lymphocyte DNA is highly valuable and accurate for prognostic assessment.

Disease Progression↗
PubMed1996

Factors associated with microsporidial and cryptosporidial diarrhea in HIV infected patients.

Cryptosporidium and microsporidia are increasingly recognized as important agents of chronic diarrhea in human immunodeficiency virus (HIV) infected patients. These protozoa present clinical and biological similarities but coinfection with these two parasites seems uncommon in a population of diarrheic HIV infected patients in the Paris area (France), a comparison study was performed in order to clarify epidemiological differences between these protozoa. From November 1993 to December 1994, 26 microsporidial infected patients were compared to 28 cryptosporidial patients for various factors. Results of a multivariate logistic regression analysis showed that trips to tropical countries remained strongly associated with microsporidic compared with Cryptosporidium adjusted odds ratio [OR] = 4.6, 95% confidence interval [CI] 1.1-19.5). Thus, as compared with cryptosporidiosis, specific epidemiological factors could be associated with microsporidial transmission in tropical countries.

AIDS-Related Opportunistic Infections↗
PubMed1995

In vitro biotransformation of 2-methylpropene (isobutene) in rat lung tissue in comparison with liver tissue.

The epoxidation of the gaseous alkene 2-methylpropene or isobutene was studied in vitro in rat lung tissue in comparison with rat liver. Pulmonary tissue appears to be less exposed to the toxic epoxide metabolite than is the case for hepatic tissue. The results are correlated with the low capacity of the mixed function oxidase system, expressed by means of the cytochrome P-450 content and the 7-ethoxycoumarin O-deethylase activity, to form reactive intermediates. The activities of the principal epoxide detoxifying enzymes glutathione S-transferase and epoxide hydrolase represent only 5-10% of the values measured in rat liver.

Alkenes↗