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A Alcais

Publications and source records attributed to A Alcais.

6 recordsLinked to original sources
PubMed2003

Segregation of HLA/TNF region is linked to leprosy clinical spectrum in families displaying mixed leprosy subtypes.

Each year an estimated 600000 new leprosy cases are diagnosed worldwide. The spectrum of the disease varies widely from limited tuberculoid forms to extensive lepromatous forms. A measure of the risk to develop lepromatous forms of leprosy is provided by the extent of skin reactivity to lepromin (Mitsuda reaction). To address a postulated oligogenic control of leprosy pathogenesis, we investigated in the present study linkage of leprosy susceptibility, leprosy clinical subtypes, and extent of the Mitsuda reaction to six chromosomal regions carrying known or suspected leprosy susceptibility loci. The only significant result obtained was linkage of leprosy clinical subtype to the HLA/TNF region on human chromosome 6p21 (P(corrected)=0.00126). In addition, we established that within the same family different HLA/TNF haplotypes segregate into patients with different leprosy subtypes directly demonstrating the importance of this genome region for the control of clinical leprosy presentation.

Chromosomes, Human, Pair 6↗
PubMed2001

[Efficacy of the combination of DEET (20%) and EHD (15%) against mosquito bites. Results of a study carried out in Senegal].

The authors report the results of a survey on the efficacy against mosquito bites of a repellent, Mousticologne Spécial Zones Infestées (DEET 20%, EHD 15%). Two forms of the product, spray and gel, were tested in Senegal. Repellent efficacy was evaluated by exposing volunteers, both repellent-treated and untreated, to mosquito bites. The number of mosquito bites per person and per night was 0.63 in the spray treated group (group 1), 6.03 in the gel treated group (group 2) and 94.17 in the untreated group (group 3). The analysis of these results showed a significant difference between treated and untreated persons. Untreated persons were not protected against mosquito bites, persons treated with the spray were protected for 12 hours and those treated with the gel had over 8 hours' protection. We concluded that a single application of the repellent Mousticologne in the field is capable of ensuring all-night protection against mosquito bites.

Aerosols↗
PubMed2000

Longitudinal changes in the ductus venosus, cerebral transverse sinus and cardiotocogram in fetal growth restriction.

OBJECTIVE: To evaluate the changes in flow velocity waveforms in the transverse cerebral sinus in growth-restricted fetuses and to correlate these changes with (1) flow velocity waveforms in the ductus venosus and (2) changes in computerized analysis of the fetal cardiotocogram. DESIGN: Fetuses between 22 and 37 weeks' gestation with an estimated fetal weight below the fifth centile were included in this prospective longitudinal study. Doppler measurements of the umbilical artery, descending aorta, middle cerebral artery, transverse cerebral sinus and ductus venosus were recorded. Fetal heart rate was analyzed by a computer system according to the Dawes-Redman criteria. RESULTS: We measured a significant correlation between pulsatility index in the cerebral transverse sinus and in the ductus venosus over the study period and at delivery. There was a negative correlation between these indices and short- and long-term variability of the fetal heart rate. There was a parallel increase in pulsatility in the ductus venosus and the transverse cerebral sinus. These changes were inversely correlated with fetal heart rate variability and preceded fetal distress. CONCLUSION: Cerebral venous blood flow in IUGR fetuses may be a useful additional investigation to discriminate between fetal adaptation and fetal decompensation in chronic hypoxemia.

Aorta↗
PubMed1998

Comparison of four sib-pair linkage methods for analyzing sibships with more than two affecteds: interest of the binomial maximum likelihood approach.

Family samples collected for sib-pair linkage studies usually include some sibships with more than two affecteds (multiplex sibships). Several methods have been proposed to take into account these multiplex sibships, and four of them are discussed in this work. Two methods, which are the most widely used, are based on the number of alleles shared by the sib-pairs constitutive of the multiplex sibship, with the first using the total number of these shared alleles ("all possible pairs" method) and the second considering a weighted number of these alleles (weighted method). The two other approaches considered the sibship as a whole, with in particular a likelihood method based on a binomial distribution of parental alleles among affected offspring. We theoretically show that, in the analysis of sibships with two affecteds, this likelihood method is expected to be more powerful than the classical mean test when a common asymptotic type I error is used. The variation of the sibship informativeness (assessed by the proportion of heterozygous parents) according to the number of affected sibs is investigated under various genetic models. Simulations under the null hypothesis of no linkage indicate that the "all possible pairs" is anticonservative, especially for type I errors < or = 0.001, whereas the weighted method generally provides satisfactory results. The likelihood method shows very consistent results in terms of type I errors, whatever the sample size, and provides power levels similar to those of the other methods. This binomial likelihood approach, which accounts in a natural way for multiplex sibships and provides a simple likelihood-ratio test for linkage involving a single parameter, appears to be a quite interesting alternative to analyze sib-pair studies.

Adult↗
PubMed1997

Risk factors for onset of cutaneous and mucocutaneous leishmaniasis in Bolivia.

A survival analysis was performed on data from an endemic area of Bolivia where two populations, natives and highland migrants, were living, to investigate risk factors for onset of cutaneous leishmaniasis (CL) and its mucosal form (MCL). In a first data set (703 subjects with 242 CL patients), significant risk factors for CL were gender, native/migrant status, activity, and home-forest distance. The instantaneous risk of CL increased until adolescence in both populations, and rapidly decreased thereafter. This risk was 3-10 times higher in migrants than in natives until 20 years of age, and became similar thereafter. Environmental and behavioral factors did not seem sufficient to explain this contrast between the two populations, and this evolution with age may suggest differences in the mechanisms involved in the development of individual protection during childhood. In a second data set (446 CL patients with 34 mucosal forms) the native/migrant status was the main factor associated with the onset of mucosal form.

Adolescent↗