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1.
J Fr Ophtalmol ; 47(5): 104117, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38696860

RESUMO

PURPOSE: To assess the incidence of Descemet's membrane endothelial keratoplasty (DMEK) rejection potentially associated with coronavirus disease 2019 (COVID-19) infection or vaccination, and its association with known rejection risk factors during the first two years of the pandemic. METHODS: This retrospective study included patients with DMEK rejection between January 2020 and December 2021. Diagnostic criteria were based on symptoms, visual acuity, and other clinical assessments. Risk factors for graft rejection were considered, and a telephone survey was conducted to identify possible preceding COVID-19 infection or vaccination. RESULTS: Of 58 patients, 44 were included. Six patients (14%) reported COVID-19 infection, with one immediate endothelial graft rejection (EGR) post-infection. After vaccine availability, 13 of 36 patients had EGR at an average of 2.7 months post-vaccination. Five (38%) had immediate EGR following vaccination, four of which had concomitant risk factors for rejection. CONCLUSION: Although the risk of endothelial graft rejection (EGR) associated with COVID-19 infection or vaccination appears to be extremely low, there may be a causative relationship, especially in patients with pre-existing risk factors for EGR. A temporary increase in anti-rejection treatment following COVID-19 infection or vaccination is recommended, especially in patients with pre-existing risk factors, along with closer monitoring during the subsequent 4 to 8 weeks.

2.
Rev Sci Instrum ; 93(12): 123302, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586889

RESUMO

For more than a decade, detonation nanodiamond (DND) powders have been actively studied as a material for efficient reflectors of very cold neutrons (VCNs) and cold neutrons. In this work, we experimentally demonstrate, for the first time, the possibility of enhanced directional extraction of a VCN beam using a reflector made of fluorinated DND powder. With respect to the theoretical flux calculated from an isotropic source at the bottom of the reflector cavity, the gain in the VCN flux density along the beam axis is ∼10 for the neutron velocities of ∼57 and ∼75 m/s. The use of such reflectors for enhanced directional extraction of VCN from neutron sources will make it possible to noticeably increase the neutron fluxes delivered to experiments and expand the scope of VCN applications.

3.
J Clin Virol ; 143: 104969, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34509927

RESUMO

BACKGROUND: The recent emergence of new SARS CoV-2 variants (variants of concern, VOC) that spread rapidly and may lead to immune escape has emphasized the urgent need to monitor and control their spread. METHODS: We analyzed 2018 SARS-CoV-2 positive specimens collected between February 9 and March 22, 2021 using the Thermofisher® TaqPath™ COVID-19 CE-IVD RT-PCR kit (TaqPath) and the ID solutions® ID™ SARS-CoV-2/UK/SA Variant Triplex RT-PCR (ID triplex) assay to screen for VOCs. RESULTS: The ID triplex assay identified 62.8% of them as VOCs: 61.8% B.1.1.7 and 0.9% B.1.351/P.1. The agreement between the ID triplex results for B.1.1.7 and the TaqPath S gene target failure (SGTF)/ S gene target late detection (SGTL) profile for this variant agreed very well (k = 0.86). A low virus load was the main cause of discrepancies. Sequencing discordant results with both assays indicated that the TaqPath assay detected the B.1.1.7 lineage slightly better. Both assays suggested that the virus loads of B.1.1.7 variants were significantly higher than those of non-B.1.1.7 strains. Only 10/20 B1.351/P.1 strains detected with the ID triplex assay were confirmed by sequencing. CONCLUSIONS: We conclude that the SGTF/SGTL profiles identified using the TaqPath assay and ID triplex results are suitable for detecting the B.1.1.7 lineage. The ID triplex assay, which rapidly determines all three current VOCs simultaneously, could be a valuable tool for limiting virus spread by supporting contact-tracing and isolation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Photodiagnosis Photodyn Ther ; 34: 102213, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33588058

RESUMO

INTRODUCTION: Actinic keratoses (AK) are a common precancerous skin condition in dermatology practice. Photodynamic therapy (PDT) with ALA or MAL is an effective but painful treatment of fields of cancerization particularly when conventional illumination sources and irradiation rates are used. Two prior studies showed that illumination with textile PDT was not inferior to conventional PDT. FLUXMEDICARE® (FLX-PDT) is the first medical device marketed with textile based lighting . We performeda real-life study to evaluate efficacy and tolerance of this device. METHODS: We carried out a single-center retrospective study. We collected data from patients treated with FLX-PDT with MAL for AKs localized on scalp and temples between November 2018 and November 2019. The primary endpoint was complete clearance rate (CR) at 3 months-follow up. RESULTS: Data of 39 patients were reviewed in the study, with a total of 417 AKs. The CR rate was 72.6 % (95 %CI 67.9-77.0) at 3 months-follow up and 67.5 % (95 %CI 61.2-73.3) at 6 months-follow up. The median pain felt during the session was 0 and there wasn't erythema after the session for 64.1 %. CONCLUSION: Our real-life study confirms efficacy and safety of textile PDT by FLUXMEDICARE device in the treatment of scalp and temples AKs, with excellent tolerance and minimal pain reported.


Assuntos
Ceratose Actínica , Fotoquimioterapia , Ácido Aminolevulínico/uso terapêutico , Humanos , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Estudos Retrospectivos , Têxteis , Resultado do Tratamento
6.
Nat Commun ; 11(1): 3317, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620775

RESUMO

Oriented cell division is a fundamental mechanism to control asymmetric stem cell division, neural tube elongation and body axis extension, among other processes. During zebrafish gastrulation, when the body axis extends, dorsal epiblast cells display divisions that are robustly oriented along the animal-vegetal embryonic axis. Here, we use a combination of lipidomics, metabolic tracer analysis and quantitative image analysis to show that sphingolipids mediate spindle positioning during oriented division of epiblast cells. We identify the Wnt signaling as a regulator of sphingolipid synthesis that mediates the activity of serine palmitoyltransferase (SPT), the first and rate-limiting enzyme in sphingolipid production. Sphingolipids determine the palmitoylation state of the Anthrax receptor, which then positions the mitotic spindle of dividing epiblast cells. Our data show how Wnt signaling mediates sphingolipid-dependent oriented division and how sphingolipids determine Anthrax receptor palmitoylation, which ultimately controls the activation of Diaphanous to mediate spindle rotation and oriented mitosis.


Assuntos
Embrião não Mamífero/metabolismo , Mitose , Receptores de Peptídeos/metabolismo , Esfingolipídeos/metabolismo , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Divisão Celular Assimétrica/genética , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Gastrulação , Regulação da Expressão Gênica no Desenvolvimento , Camadas Germinativas/citologia , Camadas Germinativas/embriologia , Camadas Germinativas/metabolismo , Lipoilação , Tubo Neural/citologia , Tubo Neural/embriologia , Tubo Neural/metabolismo , Receptores de Peptídeos/genética , Homologia de Sequência de Aminoácidos , Serina C-Palmitoiltransferase/genética , Serina C-Palmitoiltransferase/metabolismo , Fuso Acromático/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
7.
Ann Dermatol Venereol ; 147(10): 667-671, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32620295

RESUMO

INTRODUCTION: Ixekizumab is a recently developed biopharmaceutical used since 2016 in the US and Europe for the treatment of plaque psoriasis. Few adverse effects have been reported in the literature and ixekizumab is not known to increase the risk of viral reactivation. Herein we report the case of an immunocompetent female patient treated with ixekizumab who presented meningoradiculitis due to varicella zoster virus (VZV) reactivation. PATIENTS AND METHODS: A 51-year-old woman, treated with ixekizumab for psoriasis, consulted in March 2018 for left hemicrania headache associated with left facial paralysis, but without fever. Brain MRI scans revealed cerebral venous thrombosis of the superior sagittal sinus. Analysis of cerebrospinal fluid (CSF) revealed lymphocytic meningitis and positive VZV-PCR. PCR blood assay for VZV was negative. Blood concentrations of anti-VZV IgG antibody increased while Anti-VZV IgM antibodies remained negative. The final diagnosis was VZV meningoradiculitis complicated by cerebral thrombophlebitis. The absence of skin rash, the rapid increase in anti-VZV IgG antibodies, the absence of anti-VZV IgM antibodies, and the negative blood PCR assay suggested viral reactivation rather than primary infection. The patient received acyclovir and coumadin and her condition improved rapidly. After multidisciplinary discussion, ixekizumab was reintroduced together with valacyclovir prophylaxis. CONCLUSION: This case raises the question of the risk of viral reactivation during treatment with an IL-17 inhibitor and with biologics in general. Neurological and vascular complications of VZV may occur without skin lesions and their occurrence during ixekizumab therapy must be investigated by PCR testing of CSF for VZV DNA.


Assuntos
Herpes Zoster , Herpesvirus Humano 3 , Aciclovir/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Feminino , Herpes Zoster/complicações , Herpes Zoster/tratamento farmacológico , Humanos , Pessoa de Meia-Idade
8.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137(3): 227-230, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32312622

RESUMO

Intraoperative neuromonitoring of the laryngeal nerves during thyroidectomy is a reliable method to assess nerve function. After identification of the cricothyroid ligament, a bipolar electrode is selectively inserted through the ligament into the thyroarytenoid muscle (TAM) and cricothyroid muscle (CTM). Vagus nerve stimulation then allows precise monitoring of the recurrent laryngeal nerve and the external branch of the superior laryngeal nerve (EBSLN) in the TAM and CTM, respectively. A significant muscle response (greater than 100µV) is 100% predictive of preserved laryngeal mobility, while the absence of a muscle response is 70% predictive of vocal fold paralysis with 100% sensitivity and 98% specificity. A significant thyroarytenoid muscle response is only recorded ipsilateral to the stimulation with a shorter latency on the right side. A concomitant TAM and CTM response to vagus nerve stimulation or EBSLN stimulation is observed in more than 70% of cases.


Assuntos
Monitorização Neurofisiológica Intraoperatória/métodos , Nervos Laríngeos/fisiologia , Tireoidectomia , Estimulação do Nervo Vago , Humanos , Nervo Laríngeo Recorrente/fisiologia
9.
Ann Oncol ; 30(12): 1925-1940, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31617564

RESUMO

BACKGROUND: Advances in diagnostic and therapeutic strategies in oncology have significantly increased the chance of survival of cancer patients, even those with metastatic disease. However, cancer-related cognitive impairment (CRCI) is frequently reported in patients treated for non-central nervous system cancers, particularly during and after chemotherapy. DESIGN: This review provides an update of the state of the art based on PubMed searches between 2012 and March 2019 on 'cognition', 'cancer', 'antineoplastic agents' or 'chemotherapy'. It includes the most recent clinical, imaging and pre-clinical data and reports management strategies of CRCI. RESULTS: Evidence obtained primarily from studies on breast cancer patients highlight memory, processing speed, attention and executive functions as the most cognitive domains impaired post-chemotherapy. Recent investigations established that other cancer treatments, such as hormone therapies and targeted therapies, can also induce cognitive deficits. Knowledge regarding predisposing factors, biological markers or brain functions associated with CRCI has improved. Factors such as age and genetic polymorphisms of apolipoprotein E, catechol-O-methyltransferase and BDNF may predispose individuals to a higher risk of cognitive impairment. Poor performance on neuropsychological tests were associated with volume reduction in grey matter, less connectivity and activation after chemotherapy. In animals, hippocampus-based memory and executive functions, mediated by the frontal lobes, were shown to be particularly susceptible to the effects of chemotherapy. It involves altered neurogenesis, mitochondrial dysfunction or brain cytokine response. An important next step is to identify strategies for managing cognitive difficulties, with primary studies to assess cognitive training and physical exercise regimens. CONCLUSIONS: CRCI is not limited to chemotherapy. A multidisciplinary approach has improved our knowledge of the complex mechanisms involved. Nowadays, studies evaluating cognitive rehabilitation programmes are encouraged to help patients cope with cognitive difficulties and improve quality of life during and after cancer.


Assuntos
Antineoplásicos/efeitos adversos , Cognição/efeitos dos fármacos , Disfunção Cognitiva/epidemiologia , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Apolipoproteínas E/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Sobreviventes de Câncer , Catecol O-Metiltransferase/genética , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Disfunção Cognitiva/terapia , Citocinas/genética , Exercício Físico , Humanos , Neoplasias/complicações , Neoplasias/epidemiologia , Neoplasias/genética , Neurogênese/efeitos dos fármacos , Polimorfismo Genético , Qualidade de Vida
10.
Microb Genom ; 4(9)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30265232

RESUMO

Plasmid prediction may be of great interest when studying bacteria of medical importance such as Enterobacteriaceae as well as Staphylococcus aureus or Enterococcus. Indeed, many resistance and virulence genes are located on such replicons with major impact in terms of pathogenicity and spreading capacities. Beyond strain outbreak, plasmid outbreaks have been reported in particular for some extended-spectrum beta-lactamase- or carbapenemase-producing Enterobacteriaceae. Several tools are now available to explore the 'plasmidome' from whole-genome sequences with various approaches, but none of them are able to combine high sensitivity and specificity. With this in mind, we developed PlaScope, a targeted approach to recover plasmidic sequences in genome assemblies at the species or genus level. Based on Centrifuge, a metagenomic classifier, and a custom database containing complete sequences of chromosomes and plasmids from various curated databases, PlaScope classifies contigs from an assembly according to their predicted location. Compared to other plasmid classifiers, PlasFlow and cBar, it achieves better recall (0.87), specificity (0.99), precision (0.96) and accuracy (0.98) on a dataset of 70 genomes of Escherichia coli containing plasmids. In a second part, we identified 20 of the 21 chromosomal integrations of the extended-spectrum beta-lactamase coding gene in a clinical dataset of E. coli strains. In addition, we predicted virulence gene and operon locations in agreement with the literature. We also built a database for Klebsiella and correctly assigned the location for the majority of resistance genes from a collection of 12 Klebsiella pneumoniae strains. Similar approaches could also be developed for other well-characterized bacteria.


Assuntos
Genoma Bacteriano , Plasmídeos/genética , Software , Cromossomos Bacterianos , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Klebsiella pneumoniae/genética , Óperon , Fatores de Virulência/genética , Sequenciamento Completo do Genoma , Fluxo de Trabalho
11.
Phys Chem Chem Phys ; 20(22): 15350-15357, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29796573

RESUMO

The formation of highly organized structures based on two ligands with pyridyl functionalities, 4,4'-bipyridine (BPY) and 1,4-di(4,4''-pyridyl) benzene (BPYB), and Cu adatoms on the Cu(111) surface has been studied with low temperature and variable temperature scanning tunneling microscopy (STM) and first-principles calculations. We show that the formation of a highly organized adlayer built from adatom-molecule and molecule-molecule units strongly depends on the number of mobile Cu atoms on the surface. While a high concentration of Cu adatoms (high adatom/BPY ratio, ≥1) leads systematically to the formation of organometallic nanolines, their absence (low adatom/BPY ratio, ≈0) gives a compact self-assembled molecular network, and more specifically hydrogen-bond networks (HBN) with BPY molecules organized in a T-shaped fashion. Alternatively, an intermediate concentration of Cu adatoms (0 < adatom/BPY < 1) allows the formation of a well-organized and compact structure where both organometallic and HBN components coexist. Although STM images cannot clearly reveal the presence of Cu adatoms within the organometallic moiety, the bonding of BPY to a single or two Cu adatoms can be clearly identified by scanning tunneling spectroscopy (STS), and is supported by Density Functional Theory (DFT) results. Additional STM simulations suggest that the relative position of the Cu adatom with respect to the organic ligands just above has a significant impact on its detection by STM. This study exemplifies the prominent role of metallic adatoms on the formation of a complex organometallic network and should open more rational practices to optimize the formation of these supramolecular networks.

12.
Geriatr Nurs ; 39(4): 393-399, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29306500

RESUMO

We conducted a survey in a random sample of 514 Quebec nurses caring for the elderly to assess their attitudes towards extending medical aid in dying to incompetent patients and to explore associated factors. Attitudes were measured using clinical vignettes featuring a hypothetical patient with Alzheimer disease. Vignettes varied according to the stage of the disease (advanced or terminal) and the presence or absence of a written request. Of the 291 respondents, 83.5% agreed with the current legislation that allows physicians to administer aid in dying to competent patients who are at the end of life and suffer unbearably. A similar proportion (83%, p = 0.871) were in favor of extending medical aid in dying to incompetent patients who are at the terminal stage of Alzheimer disease, show signs of distress, and have made a written request before losing capacity.


Assuntos
Atitude do Pessoal de Saúde , Demência/psicologia , Eutanásia , Papel do Profissional de Enfermagem/psicologia , Assistência Terminal/métodos , Diretivas Antecipadas , Eutanásia/legislação & jurisprudência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quebeque , Inquéritos e Questionários
14.
Eur Arch Otorhinolaryngol ; 274(9): 3519-3526, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28687919

RESUMO

The aim of this study was to validate a procedure to identify and preserve the external branch of the superior laryngeal nerve (EBSLN) during thyroid surgery. The present study also aimed to analyze the EBSLN and the vagus nerve activities after stimulation and demonstrate an operative association between all the laryngeal muscles. Dissection of the cervical region was performed bilaterally in four adult cadavers. In a second step, 144 patients undergoing total thyroidectomy were included. Intraoperative stimulations of the cervical vagus nerve and the EBSLN in the sternothyroid-laryngeal triangle were performed bilaterally. Potentials in the thyroarytenoid muscle and the cricothyroid muscle were registered on each side using the NIM3 Medtronic System. EBSLN was identified according to Cernea's classification as type 1 in 62.5%, type 2a in 25%, and type 2b in 12.5% of cadaver's dissection. According to Friedman's classification, 50% of EBSLN were classified type 1, 25% type 2 and 25% type 3. The EBSLN was identified in 267 cases out of 288 peroperative dissections (92.7%). Direct stimulation (1 mA) of this branch led to a recordable contraction of the cricothyroid muscle with a mean latency of 1.42 ± 0.66 ms on the right side and 1.43 ± 0.61 ms on the left side. The stimulation of the EBSLN also led to a recordable contraction of the thyroarytenoid muscle in 211 cases (73.3%) with the same latencies. A contraction of the cricothyroid muscle was also recorded when the vagus nerve was stimulated in 219 cases (76.0%). The sole visual identification of the EBSLN during thyroid surgery is not a reliable method to prevent nerve injury. Direct stimulation of the EBSLN in the sternothyroid-laryngeal triangle is a simple and rapid procedure to detect and preserve the nerve during surgery. Functional associations between vagus nerve and EBSLN in laryngeal muscles' contractions were also identified.


Assuntos
Músculos Laríngeos/inervação , Nervos Laríngeos/anatomia & histologia , Monitorização Intraoperatória/métodos , Glândula Tireoide/inervação , Tireoidectomia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Glândula Tireoide/cirurgia , Adulto Jovem
15.
Clin Microbiol Infect ; 23(8): 574.e1-574.e6, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28192237

RESUMO

OBJECTIVE: Infections are the major cause of morbidity and mortality in immunocompromised patients. Improving microbiological diagnosis in these patients is of paramount clinical importance. METHODS: We performed this multicentre, blinded, prospective, proof-of-concept study, to compare untargeted next-generation sequencing with conventional microbiological methods for first-line diagnosis of infection in 101 immunocompromised adults. Patients were followed for 30 days and their blood samples, and in some cases nasopharyngeal swabs and/or biological fluids, were analysed. At the end of the study, expert clinicians evaluated the results of both methods. The primary outcome measure was the detection rate of clinically relevant viruses and bacteria at inclusion. RESULTS: Clinically relevant viruses and bacteria identified by untargeted next-generation sequencing and conventional methods were concordant for 72 of 101 patients in samples taken at inclusion (κ test=0.2, 95% CI 0.03-0.48). However, clinically relevant viruses and bacteria were detected in a significantly higher proportion of patients with untargeted next-generation sequencing than conventional methods at inclusion (36/101 (36%) vs. 11/101 (11%), respectively, p <0.001), and even when the latter were continued over 30 days (19/101 (19%), p 0.003). Untargeted next-generation sequencing had a high negative predictive value compared with conventional methods (64/65, 95% CI 0.95-1). CONCLUSIONS: Untargeted next-generation sequencing has a high negative predictive value and detects more clinically relevant viruses and bacteria than conventional microbiological methods. Untargeted next-generation sequencing is therefore a promising method for microbiological diagnosis in immunocompromised adults.


Assuntos
Doenças Transmissíveis/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Hospedeiro Imunocomprometido , Técnicas de Diagnóstico Molecular/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudo de Prova de Conceito , Estudos Prospectivos
16.
Mol Ecol ; 26(3): 887-903, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28026895

RESUMO

Population genetic studies are efficient for inferring the invasion history based on a comparison of native and invasive populations, especially when conducted at species scale. An expected outcome in invasive populations is variability loss, and this is especially true in self-fertilizing species. We here focus on the self-fertilizing Pseudosuccinea columella, an invasive hermaphroditic freshwater snail that has greatly expanded its geographic distribution and that acts as intermediate host of Fasciola hepatica, the causative agent of human and veterinary fasciolosis. We evaluated the distribution of genetic diversity at the largest geographic scale analysed to date in this species by surveying 80 populations collected during 16 years from 14 countries, using eight nuclear microsatellites and two mitochondrial genes. As expected, populations from North America, the putative origin area, were strongly structured by selfing and history and harboured much more genetic variability than invasive populations. We found high selfing rates (when it was possible to infer it), none-to-low genetic variability and strong population structure in most invasive populations. Strikingly, we found a unique genotype/haplotype in populations from eight invaded regions sampled all over the world. Moreover, snail populations resistant to infection by the parasite are genetically distinct from susceptible populations. Our results are compatible with repeated introductions in South America and flash worldwide invasion by this unique genotype/haplotype. Our study illustrates the population genetic consequences of biological invasion in a highly selfing species at very large geographic scale. We discuss how such a large-scale flash invasion may affect the spread of fasciolosis.


Assuntos
Genética Populacional , Autofertilização , Caramujos/genética , Animais , Genes Mitocondriais , Genótipo , Haplótipos , Espécies Introduzidas , Repetições de Microssatélites , América do Norte , América do Sul
17.
Mol Ecol ; 25(22): 5611-5627, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27717090

RESUMO

The life cycles and dispersal of edible fungi are still poorly known, thus limiting our understanding of their evolution and domestication. The prized Tuber melanosporum produces fruitbodies (fleshy organs where meiospores mature) gathered in natural, spontaneously inoculated forests or harvested in plantations of nursery-inoculated trees. Yet, how fruitbodies are formed remains unclear, thus limiting yields, and how current domestication attempts affect population genetic structure is overlooked. Fruitbodies result from mating between two haploid individuals: the maternal parent forms the flesh and the meiospores, while the paternal parent only contributes to the meiospores. We analyzed the genetic diversity of T. melanosporum comparatively in spontaneous forests vs. plantations, using SSR polymorphism of 950 samples from South-East France. All populations displayed strong genetic isolation by distance at the metric scale, possibly due to animal dispersal, meiospore persistence in soil, and/or exclusion of unrelated individuals by vegetative incompatibility. High inbreeding was consistently found, suggesting that parents often develop from meiospores produced by the same fruitbody. Unlike maternal genotypes, paternal mycelia contributed to few fruitbodies each, did not persist over years, and were undetectable on tree mycorrhizae. Thus, we postulate that germlings from the soil spore bank act as paternal partners. Paternal genetic diversity and outbreeding were higher in plantations than in spontaneous truffle-grounds, perhaps because truffle growers disperse fruitbodies to maintain inoculation in plantations. However, planted and spontaneous populations were not genetically isolated, so that T. melanosporum illustrates an early step of domestication where genetic structure remains little affected.


Assuntos
Ascomicetos/genética , Variação Genética , Genética Populacional , Microbiologia do Solo , Florestas , França , Repetições de Microssatélites , Micorrizas
18.
Rev Sci Instrum ; 87(2): 02B508, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932061

RESUMO

In the framework of the SPIRAL1 upgrade under progress at the GANIL lab, the charge breeder based on a LPSC Phoenix ECRIS, first tested at ISOLDE has been modified to benefit of the last enhancements of this device from the 1+/n+ community. The modifications mainly concern the 1 + optics, vacuum techniques, and the RF-buffer gas injection into the charge breeder. Prior to its installation in the midst of the low energy beam line of the SPIRAL1 facility, it has been decided to qualify its performances and several operation modes at the test bench of LPSC lab. This contribution shall present preliminary results of experiments conducted at LPSC concerning the 1 + to n+ conversion efficiencies for noble gases as well as for alkali elements and the corresponding transformation times.

19.
Hum Reprod ; 31(1): 93-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26537922

RESUMO

STUDY QUESTION: How do the national cumulative (multiple) live birth rates over complete assisted reproduction technology (ART) courses of treatment per woman in Belgium compare to those in other registries? SUMMARY ANSWER: Cumulative live birth rates (CLBRs) remain high with a low cumulative multiple live birth rate when compared with other registries and publications. WHAT IS KNOWN ALREADY: In ART, a reduction in the multiple live birth rate could be achieved by reducing the number of embryos transferred. It has been shown that by doing so, live birth rates per cycle were maintained, particularly when the augmentation effect of attached frozen-thawed cycles was considered. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study included all patients with a Belgian national insurance number who were registered in the national ART registry (Belrap) and who started a first fresh ART cycle between 1 July 2009 until 31 December 2011 with follow up until 31 December 2012. We analysed 12 869 patients and 38 008 cycles (both fresh and attached frozen cycles). PARTICIPANTS, MATERIALS, SETTINGS, METHODS: CLBRs per patient who started a first ART cycle including fresh and consecutive frozen cycles leading to a live birth. Conservative estimates of cumulative live birth assumed that patients who did not return for treatment had no chance of achieving an ART-related live birth, whereas optimal estimates assumed that women discontinuing treatment would have the same chance of achieving a live birth as those continuing treatment. A maximum of six fresh ART cycles with corresponding frozen cycles was investigated and compared with other registries and publications. MAIN RESULTS AND ROLE OF CHANCE: The CLBR was age dependent and declined from 62.9% for women <35 years, to 51.4% for women 35-37 years, to 34.1% for women 38-40 years and 17.7% for women 41-42 years in the conservative analysis after six cycles. In the optimal estimate, the CLBR declined from 85.9% for women <35 years, to 72.0% for women 35-37 years, to 50.4% for women 38-40 years and 36.4% for women 41-42 years. The cumulative multiple live birth rates for the whole population were 5.1 and 8.6% for the conservative and optimal estimate, respectively. LIMITATIONS, REASONS FOR CAUTION: Conservative and optimal estimates use assumptions for the whole ART population and do not take the individual patient into account. WIDER IMPLICATIONS OF THE FINDINGS: These data reinforce the validity of the Belgian model of coupling reimbursement of ART costs to a restriction in the number of embryos transferred. Our data can improve decision-making in medical ART practice both on the patient level and for society at large and could provide health care takers and insurance companies with a valid model. STUDY FUNDING COMPETING INTERESTS: none.


Assuntos
Infertilidade Feminina/terapia , Nascido Vivo/epidemiologia , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Técnicas de Reprodução Assistida/estatística & dados numéricos , Adulto , Bélgica/epidemiologia , Feminino , Humanos , Infertilidade Feminina/epidemiologia , Gravidez
20.
Phys Rev Lett ; 114(1): 013902, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25615470

RESUMO

The flat-lens concept based on negative refraction proposed by Veselago in 1968 has been mostly investigated in the monochromatic regime. It was recently recognized that time development of the superlensing effect discovered in 2000 by Pendry is yet to be assessed and may spring surprises: Time-dependent illumination could improve the spatial resolution of the focusing. We investigate dynamics of flexural wave focusing by a 45°-tilted square lattice of circular holes drilled in a duralumin plate. Time-resolved experiments reveal that the focused image shrinks with time below the diffraction limit, with a lateral resolution increasing from 0.8λ to 0.35λ, whereas focusing under harmonic excitation remains diffraction limited. Modal analysis reveals the role in pulse reconstruction of radiating lens resonances, which repeatedly self-synchronize at the focal spot to shape a superoscillating field.

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