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2.
Arch Pediatr ; 23(1): 39-44, 2016 Jan.
Artigo em Francês | MEDLINE | ID: mdl-26586547

RESUMO

INTRODUCTION: While the number of international adoptions in France is decreasing, adopted children are older and in poorer health than they used to be. This phenomenon has resulted in an increase in the demand for preadoption consultations over the past several years. This study analyses the reasons for these consultations. METHOD: Prospective multicenter study conducted from 1 January to 31 December 2013. RESULTS: Ten centers contributed to the study, i.e., 196 preadoption consultations. Seeking medical advice was the reason for 88% of the consultations, whether the advice was based on the study of an identified child's medical file (32%) or a country's healthcare characteristics, whether the country was identified (34%) or not (23%). In 6% of cases, the motive for preadoption consultations was social and familial, and in the last 5% it was to obtain general information about adoption and its procedures. In more than 40% of the cases, whether the child or the country identified, Russia is the subject of the consultation because of the complexity of the files and because of the dreaded but rarely mentioned fetal alcohol syndrome. CONCLUSION: The deterioration of adopted children's health is an additional worry for future adoption applicants. To provide them with the best information possible without making choices for them, specialists should have substantial experience in adoption before going into these preadoption consultations.


Assuntos
Adoção , Nível de Saúde , Motivação , Encaminhamento e Consulta/estatística & dados numéricos , Pré-Escolar , Feminino , França , Humanos , Internacionalidade , Masculino , Estudos Prospectivos
3.
J Phys Condens Matter ; 27(16): 164208, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25835486

RESUMO

We report on electron cooling power measurements in few-layer graphene excited by Joule heating by means of a new setup combining electrical and optical probes of the electron and phonon baths temperatures. At low bias, noise thermometry allows us to retrieve the well known acoustic phonon cooling regimes below and above the Bloch-Grüneisen temperature, with additional control over the phonon bath temperature. At high electrical bias, we show the relevance of direct optical investigation of the electronic temperature by means of black-body radiation measurements. In this regime, the onset of new efficient relaxation pathways involving optical modes is observed.

4.
Theor Appl Genet ; 127(11): 2313-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25301321

RESUMO

KEY MESSAGE: Genetic and phenotypic analysis of two complementary maize panels revealed an important variation for biomass yield. Flowering and biomass QTL were discovered by association mapping in both panels. The high whole plant biomass productivity of maize makes it a potential source of energy in animal feeding and biofuel production. The variability and the genetic determinism of traits related to biomass are poorly known. We analyzed two highly diverse panels of Dent and Flint lines representing complementary heterotic groups for Northern Europe. They were genotyped with the 50 k SNP-array and phenotyped as hybrids (crossed to a tester of the complementary pool) in a western European field trial network for traits related to flowering time, plant height, and biomass. The molecular information revealed to be a powerful tool for discovering different levels of structure and relatedness in both panels. This study revealed important variation and potential genetic progress for biomass production, even at constant precocity. Association mapping was run by combining genotypes and phenotypes in a mixed model with a random polygenic effect. This permitted the detection of significant associations, confirming height and flowering time quantitative trait loci (QTL) found in literature. Biomass yield QTL were detected in both panels but were unstable across the environments. Alternative kinship estimator only based on markers unlinked to the tested SNP increased the number of significant associations by around 40% with a satisfying control of the false positive rate. This study gave insights into the variability and the genetic architectures of biomass-related traits in Flint and Dent lines and suggests important potential of these two pools for breeding high biomass yielding hybrid varieties.


Assuntos
Biomassa , Locos de Características Quantitativas , Zea mays/genética , Cruzamento , Mapeamento Cromossômico , Flores/fisiologia , Frequência do Gene , Genótipo , Vigor Híbrido , Desequilíbrio de Ligação , Modelos Genéticos , Modelos Estatísticos , Fenótipo , Polimorfismo de Nucleotídeo Único , Zea mays/crescimento & desenvolvimento
5.
Arch Pediatr ; 20(5): 476-83, 2013 May.
Artigo em Francês | MEDLINE | ID: mdl-23562318

RESUMO

AIM: Whether or not voiding cystourethrography (VCUG) should be performed after a first episode of urinary tract infection (UTI) remains a matter of debate. The role of VCUG is primarily to diagnose high-grade vesicoureteral reflux (≥grade III) (VUR) and hence prevent the development of renal scars and poor long-term outcome. We designed a protocol designed to reduce the indications for performing unnecessary VCUGs after a first episode of febrile UTI. In order to evaluate the efficacy of our protocol, we designed a retrospective study to verify whether high-grade VUR was subsequently being underdiagnosed. METHODS: This study compared the number of cases of VUR diagnosed over 2 1-year periods in children aged 1 month to 18 years. Data were collected from records held in the pediatric emergency department of the University Hospital of Reims. All cases included had presented to the department with a first episode of febrile UTI. During the first 1-year collection period, all patients underwent a VCUG. During the second collection period, the protocol was in place and VCUG was only performed in children with a serum procalcitonin level greater than 1 ng/L and/or an abnormal renal ultrasound scan. RESULTS: During the first year, 100 patients underwent routine VCUG and 7 cases of high-grade VUR were diagnosed. During the following year, VCUG was limited according to the new protocol: 102 patients were enrolled, 52 VCUGs were performed and 8 cases of high-grade VUR were diagnosed. Cases of low-grade VUR (I and II) were less frequently detected, without significant consequences for the patients. CONCLUSION: The protocol led to a 40% decrease in the number of VCUGs performed. No cases of high-grade VUR were missed; however, the number of VCUGs performed with a normal outcome remained significant.


Assuntos
Procedimentos Desnecessários/estatística & dados numéricos , Infecções Urinárias/diagnóstico por imagem , Urografia/estatística & dados numéricos , Refluxo Vesicoureteral/diagnóstico por imagem , Adolescente , Antibacterianos/administração & dosagem , Bacteriúria/diagnóstico por imagem , Criança , Pré-Escolar , Procedimentos Clínicos , Diagnóstico Tardio/estatística & dados numéricos , Quimioterapia Combinada , Feminino , França , Hospitais Universitários , Humanos , Lactente , Recém-Nascido , Infusões Intravenosas , Masculino , Estudos Retrospectivos , Bexiga Urinária/diagnóstico por imagem , Infecções Urinárias/tratamento farmacológico , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricos
6.
Phys Rev Lett ; 109(5): 056805, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-23006198

RESUMO

We have investigated the energy loss of hot electrons in metallic graphene by means of GHz noise thermometry at liquid helium temperature. We observe the electronic temperature T ∝ V at low bias in agreement with the heat diffusion to the leads described by the Wiedemann-Franz law. We report on T ∝ √V behavior at high bias, which corresponds to a T(4) dependence of the cooling power. This is the signature of a 2D acoustic phonon cooling mechanism. From a heat equation analysis of the two regimes we extract accurate values of the electron-acoustic phonon coupling constant Σ in monolayer graphene. Our measurements point to an important effect of lattice disorder in the reduction of Σ, not yet considered by theory. Moreover, our study provides a strong and firm support to the rising field of graphene bolometric detectors.

7.
Genetics ; 192(2): 715-28, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22865733

RESUMO

Genomic selection refers to the use of genotypic information for predicting breeding values of selection candidates. A prediction formula is calibrated with the genotypes and phenotypes of reference individuals constituting the calibration set. The size and the composition of this set are essential parameters affecting the prediction reliabilities. The objective of this study was to maximize reliabilities by optimizing the calibration set. Different criteria based on the diversity or on the prediction error variance (PEV) derived from the realized additive relationship matrix-best linear unbiased predictions model (RA-BLUP) were used to select the reference individuals. For the latter, we considered the mean of the PEV of the contrasts between each selection candidate and the mean of the population (PEVmean) and the mean of the expected reliabilities of the same contrasts (CDmean). These criteria were tested with phenotypic data collected on two diversity panels of maize (Zea mays L.) genotyped with a 50k SNPs array. In the two panels, samples chosen based on CDmean gave higher reliabilities than random samples for various calibration set sizes. CDmean also appeared superior to PEVmean, which can be explained by the fact that it takes into account the reduction of variance due to the relatedness between individuals. Selected samples were close to optimality for a wide range of trait heritabilities, which suggests that the strategy presented here can efficiently sample subsets in panels of inbred lines. A script to optimize reference samples based on CDmean is available on request.


Assuntos
Estudos de Associação Genética , Genoma de Planta , Modelos Estatísticos , Fenótipo , Zea mays/genética , Algoritmos , Variação Genética , Genética Populacional , Endogamia , Polimorfismo de Nucleotídeo Único/genética , Padrões de Referência , Seleção Genética
8.
Ann Dermatol Venereol ; 137(12): 775-81, 2010 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21134579

RESUMO

BACKGROUND: acute idiopathic scrotal oedema (AISO) is most commonly seen in boys aged between 5 and 10 years. It comprises a benign dermatosis of spontaneously favourable outcome but requiring surgical exploration in some cases in order to rule out testicular torsion. Our retrospective study of a series of 10 children presenting AISO allowed us to set out the specific features of this dermatological disorder well-known to paediatric surgeons, but concerning which only one publication exists in the dermatology literature. PATIENTS AND METHODS: this was a retrospective study of the files of all children seen in the paediatric surgery department of Reims University Hospital between 1996 and 2008 for acute scrotal oedema. Diagnosis of AISO was made on the basis of clinical criteria after ruling out potential differential diagnosis. The demographic, clinical and laboratory data were collated from patient files. Long-term outcome was determined by means of telephone calls. RESULTS: among 185 cases of acute scrotal disease, 10 cases of AISO (5.4%) were identified. The mean age at onset of the initial episode was 6 years (range: 3 to 12 years). Oedema was unilateral in eight cases and bilateral in two cases; there was involvement of the inguinal folds, the perineum and the homolateral buttock in three cases, and of the penis in one case. The skin was erythematous and relatively non-inflamed in all but one case. Non-focal scrotal pain was present on palpation in nine cases. General health status was unimpaired and none of the children presented any associated signs. White cell count was between 7000 and 12000 per millimeter cube, with no neutrophil polynucleosis or inflammatory syndrome; in three cases, hypereosinophilia was between 700 and 2300 per millimeter cube. Two patients underwent surgical exploration to rule out testicular torsion; Doppler ultrasound was performed in the remaining eight cases and no surgery was required in six cases. In all cases, a favourable outcome was attained within 2 to 3 days and there were no sequelae. Five children presented a total of 21 recurrences (between three and eight per child) over a maximum period of 12 years. DISCUSSION: the clinical characteristics of our patients are entirely consistent with the descriptions given in the literature. The chief problem with AISO is differential diagnosis; in this respect, Doppler ultrasound may be useful in obviating surgical investigation for testicular torsion. Treatment involves bed rest and analgesics where necessary; a rapidly favourable outcome is achieved within 2 to 3 days, but relapse occurs in at least 20% of cases, although these were more frequent and more numerous in our series. The aetiopathogenesis has not yet been fully elucidated. CONCLUSION: Identification of AISO, a fairly stereotypical though misunderstood diagnostic entity, is useful in order to avoid unwarranted medical treatment and, above all, unnecessary surgical exploration.


Assuntos
Edema/etiologia , Doenças dos Genitais Masculinos/etiologia , Escroto , Dermatopatias/etiologia , Doença Aguda , Criança , Pré-Escolar , Diagnóstico Diferencial , Edema/diagnóstico , Edema/cirurgia , Seguimentos , Doenças dos Genitais Masculinos/diagnóstico , Doenças dos Genitais Masculinos/cirurgia , Humanos , Masculino , Recidiva , Estudos Retrospectivos , Dermatopatias/diagnóstico , Dermatopatias/cirurgia , Torção do Cordão Espermático/diagnóstico , Torção do Cordão Espermático/cirurgia , Ultrassonografia Doppler
9.
Genetics ; 179(2): 997-1008, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18558653

RESUMO

Sorghum has shown the adaptability necessary to sustain its improvement during time and geographical extension despite a genetic foundation constricted by domestication bottlenecks. Initially domesticated in the northeastern part of sub-Saharan Africa several millenia ago, sorghum quickly spread throughout Africa, and to Asia. We performed phylogeographic analysis of sequence diversity for six candidate genes for grain quality (Shrunken2, Brittle2, Soluble starch synthaseI, Waxy, Amylose extender1, and Opaque2) in a representative sample of sorghum cultivars. Haplotypes along 1-kb segments appeared little affected by recombination. Sequence similarity enabled clustering of closely related alleles and discrimination of two or three distantly related groups depending on the gene. This scheme indicated that sorghum domestication involved structured founder populations, while confirming a specific status for the guinea margaritiferum subrace. Allele rooted genealogy revealed derivation relationships by mutation or, less frequently, by recombination. Comparison of germplasm compartments revealed contrasts between genes. Sh2, Bt2, and SssI displayed a loss of diversity outside the area of origin of sorghum, whereas O2 and, to some extent, Wx and Ae1 displayed novel variation, derived from postdomestication mutations. These are likely to have been conserved under the effect of human selection, thus releasing valuable neodiversity whose extent will influence germplasm management strategies.


Assuntos
Variação Genética , Filogenia , Sorghum/genética , África , Ásia , Sequência de Bases , Cruzamento , DNA de Plantas/genética , Efeito Fundador , Genes de Plantas , Haplótipos , Modelos Genéticos , Dados de Sequência Molecular , Mutação , Sorghum/classificação
10.
J Chromatogr A ; 1160(1-2): 150-9, 2007 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-17537447

RESUMO

In the last decade, silica monolithic capillaries have focused more and more attention on miniaturized separation techniques like capillary electrochromatography (CEC), nano-liquid chromatography (nano-LC) and chip electrochromatography owing to their unique chromatographic properties and their simplified preparation compared with packed columns. They are synthesized according to a sol-gel multi-step process that includes, after a gelation step at 40 degrees C leading to the formation of the macropores network and the silica skeleton, a post-gelation step (hydrothermal treatment at 120 degrees C in basic medium) that allows to tailor the mesopores and finally a calcination or a washing step to remove remaining polymers. In order to reduce the synthesis time, the number of synthesis steps and above all the temperature synthesis, to adapt the synthesis of such silica monoliths in polymeric microsystem devices, we extensively studied the influence of the hydrothermal treatment and its duration on textural (pore size distribution) and chromatographic properties (retention, efficiency) of in situ-synthesized capillary monoliths in nano-LC and CEC. This study was performed on pure silica and octyl chains grafted silica monoliths. Untreated monoliths show small pores (<6 nm), whereas hydrothermally treated monoliths exhibit medium and large mesopores (8-17 nm). It was demonstrated that the hydrothermal treatment at 120 degrees C was not necessary for pure silica monolithic capillaries dedicated to normal phase liquid chromatography or hydrophilic interaction liquid chromatography (HILIC) and electrochromatography: the suppression of the hydrothermal treatment did not impair efficiencies in CEC and in nano-LC but contributed to increase in retention factors. Minimal plate heights of ca. 5 microm in CEC and 6 microm in nano-LC were obtained with or without hydrothermal treatment with bare silica. In the same way, the hydrothermal treatment was not necessary for grafted silica monoliths only dedicated to CEC. However, the results clearly indicate that the hydrothermal treatment becomes essential before grafting in order to preserve the efficiency of the monolithic silica capillaries dedicated to nano-LC: in this particular case, the suppression of the hydrothermal treatment leads approximately to a loss of a factor two in efficiency.


Assuntos
Eletrocromatografia Capilar/métodos , Nanotecnologia/métodos , Dióxido de Silício/química , Temperatura , Água , Adsorção , Nitrogênio , Compostos de Fenilureia/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Porosidade , Xantinas/isolamento & purificação
11.
Mol Biol Evol ; 24(7): 1506-17, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17443011

RESUMO

Several demographic and selective events occurred during the domestication of wheat from the allotetraploid wild emmer (Triticum turgidum ssp. dicoccoides). Cultivated wheat has since been affected by other historical events. We analyzed nucleotide diversity at 21 loci in a sample of 101 individuals representing 4 taxa corresponding to representative steps in the recent evolution of wheat (wild, domesticated, cultivated durum, and bread wheats) to unravel the evolutionary history of cultivated wheats and to quantify its impact on genetic diversity. Sequence relationships are consistent with a single domestication event and identify 2 genetically different groups of bread wheat. The wild group is not highly polymorphic, with only 212 polymorphic sites among the 21,720 bp sequenced, and, during domestication, diversity was further reduced in cultivated forms--by 69% in bread wheat and 84% in durum wheat--with considerable differences between loci, some retaining no polymorphism at all. Coalescent simulations were performed and compared with our data to estimate the intensity of the bottlenecks associated with domestication and subsequent selection. Based on our 21-locus analysis, the average intensity of domestication bottleneck was estimated at about 3--giving a population size for the domesticated form about one third that of wild dicoccoides. The most severe bottleneck, with an intensity of about 6, occurred in the evolution of durum wheat. We investigated whether some of the genes departed from the empirical distribution of most loci, suggesting that they might have been selected during domestication or breeding. We detected a departure from the null model of demographic bottleneck for the hypothetical gene HgA. However, the atypical pattern of polymorphism at this locus might reveal selection on the linked locus Gsp1A, which may affect grain softness--an important trait for end-use quality in wheat.


Assuntos
Variação Genética , Triticum/genética , Manipulação de Alimentos , Funções Verossimilhança , Nucleotídeos/genética , Filogenia , Polimorfismo Genético
12.
Chem Commun (Camb) ; (1): 24-5, 2002 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-12120292

RESUMO

Texture-related features of water intrusion in hydrophobised MCM-41 silicas render these materials especially suitable for energy dissipation in mechanical dampers.

13.
Theor Appl Genet ; 105(8): 1196-1206, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12582899

RESUMO

The evolution of genomes can be studied by comparing maps of homologous genes which show changes in nucleic acid sequences and chromosome rearrangements. In this study, we developed a set of 32 amplified consensus gene markers (ACGMs) that amplified gene sequences from Arabidopsis thaliana and Brassica napus. Our methodology, based on PCR, facilitated the rapid sequencing of homologous genes from various species of the same phylogenetic family and the detection of intragenic polymorphism. We found that such polymorphism principally concerned intron sequences and we used it to attribute a Brassica oleracea or Brassica rapa origin to the B. napus sequences and to map 43 rapeseed genes. We confirm that the genetic position of homologous genes varied between B. napus and A. thaliana. ACGMs are a useful tool for genome evolution studies and for the further development of single nucleotide polymorphism suitable for use in genetic mapping and genetic diversity analyses.

14.
Genome ; 44(6): 1083-99, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768212

RESUMO

Numerous sequences analogous to resistance (R) genes exist in plant genomes and could be involved in resistance traits. The aim of this study was to identify a large number of Brassica napus sequences related to R genes and also to test the adequacy of specific PCR-based tools for studying them. Different consensus primers were compared for their efficiency in amplifying resistance-gene analogues (RGAs) related to the nucleotide-binding-site subgroup of R genes. Specific primers were subsequently designed to fine-study the different RGAs and we tested their efficiency in three species related to B. napus: Brassica oleracea, Brassica rapa, and Arabidopsis thaliana. Forty-four B. napus RGAs were identified. Among 29 examined, at least one-third were expressed. Eighteen RGAs were mapped on 10 of the 19 B. napus linkage groups. The high variability within these sequences permitted discrimination of each genotype within a B. napus collection. The RGA-specific primers amplified RGAs in the B. oleracea and B. rapa genomes, but the sequences appear to be poorly conserved in A. thaliana. Specific RGA primers are a precise tool for studying known-sequence RGAs. These sequences represent interesting markers that could be correlated with resistance traits in B. napus or related Brassica genomes.


Assuntos
Brassica napus/genética , Mapeamento Cromossômico , Variação Genética , Doenças das Plantas/genética , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Sequência Conservada/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Dados de Sequência Molecular , Alinhamento de Sequência
15.
Genome ; 42(3): 387-402, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10382288

RESUMO

A method for the development of consensus genetic markers between species of the same taxonomic family is described in this paper. It is based on the conservation of the peptide sequences and on the potential polymorphism within non-coding sequences. Six loci sequenced from Arabidopsis thaliana, AG, LFY3, AP3, FAD7, FAD3, and ADH, were analysed for one ecotype of A. thaliana, four lines of Brassica napus, and one line for each parental species, Brassica oleracea and Brassica rapa. Positive amplifications with the degenerate primers showed one band for A. thaliana, two to four bands in rapeseed, and one to two bands in the parental species. Direct sequencing of the PCR products confirms their peptide similarity with the "mother" sequence. By comparison of intron sequences, the correspondence between each rapeseed gene and its homologue in one of the parental species can be determined without ambiguity. Another important result is the presence of a polymorphism inside these fragments between the rapeseed lines. This variability could generally be detected by differences of electrophoretic migration on long non-denaturing polyacrylamide gels. This method enables a quick and easy shuttle between A. thaliana and Brassica species without cloning.


Assuntos
Arabidopsis/genética , Brassica/genética , Sequência de Aminoácidos , Sequência de Bases , Sequência Consenso , Primers do DNA , Genes de Plantas , Marcadores Genéticos , Genótipo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Software
18.
Theor Appl Genet ; 93(4): 512-8, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24162342

RESUMO

In rapeseed, which is an agronomically important oilseed, variation in the linolenic acid content of the oil has been obtained through chemical mutagenesis treatment. Conventional breeding of this quantitative trait, however requires specific molecular markers. By means of biochemical experiments, we have established that the induced variation in linolenic acid content is associated with the fad3 gene encoding the microsomal Δ(15) desaturase. Using a pair of primers specific to this gene and a doubled haploid progeny derived from a low linolenic x high linolenic acid F1hybrid, we have identified a polymorphism of the fad3 alleles between the low- and the high-linolenic acid genotypes. The structure exon/intron of the fad3 DNA sequence seems to be very similar to that of the Arabidopsis fad3 gene. The choice of the primer pair allows specific amplification of one of the two rapeseed fad3 genes. The value and contribution of specific markers to conventional plant breeding is discussed.

19.
Plant Mol Biol ; 24(2): 397-400, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8111041

RESUMO

The importance of genetic polymorphism detected by 'microsatellites' is now well established in mammalian genomes. Sequences with a CA repeat, specific to sunflower, Helianthus annuus L., were found by screening a genomic library in M13. After amplification, some polymorphism was detected on these sequences within a sample of cultivars and populations.


Assuntos
DNA Satélite/genética , Marcadores Genéticos , Helianthus/genética , Sequência de Bases , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
20.
Theor Appl Genet ; 88(1): 49-55, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24185881

RESUMO

Nine polymorphic isoenzymatic systems were studied in 39 cultivated sunflower populations originating from ten countries. Analysis of combining abilities with four tester lines was also performed on these populations for seed yield, seed moisture and seed oil content. The MDH, PGI, PGD and GOT systems appeared to provide the best discrimination of specific combining ability effects with the four testers. The MDH and GOT systems provided a between-population structure that was consistent with the country of origin.

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