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1.
Vox Sang ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218425

RESUMO

BACKGROUND AND OBJECTIVES: In 2016, France allowed men who have sex with men (MSM) to donate blood if they had not had sex with men in the previous 12 months. In April 2020, this restriction was relaxed to 4 months due to the lack of negative impact observed on blood safety. This study assesses the impact of reducing this deferral period on epidemiological surveillance indicators. MATERIALS AND METHODS: This study compares infection surveillance indicators between two 30-month periods before (P1) and after (P2) this second deferral change. RESULTS: Overall, 79 donations tested positive for human immunodeficiency virus (HIV) (49 in P1 and 30 in P2), 322 for hepatitis C virus (HCV) (185 and 137), 622 for hepatitis B virus (HBV) (355 and 267) and 1684 for syphilis (799 and 885). Positive donation rates decreased between P1 and P2, except for syphilis: HIV (0.07/10,000 donations vs. 0.04; p > 0.5), HCV (0.25 vs. 0.20; p < 0.05), HBV (0.49 vs. 0.39; p < 0.01) and syphilis (1.10 vs. 1.29; p < 0.001). For all three viruses, residual risks of transmission by transfusion did not increase: HIV (1/7,800,000 donations vs. 1/10,500,000), HCV (1/25,200,000 vs. 1/47,300,000) and HBV (1/6,400,000 vs. 1/6,000,000). CONCLUSION: Reducing the deferral period for MSM in April 2020 did not negatively impact residual risks, which remained very low, or the rate of positive donations, except for syphilis, which requires careful monitoring. To ensure equal access to blood donation, MSM have been allowed to donate blood under the same conditions as other donors since March 2022 (i.e., no more than one sexual partner in the last 4 months).

2.
J Evol Biol ; 29(8): 1593-601, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27177256

RESUMO

In the context of global changes, the long-term viability of populations of endangered ectotherms may depend on their adaptive potential and ability to cope with temperature variations. We measured responses of Atlantic salmon embryos from four populations to temperature variations and used a QST -FST approach to study the adaptive divergence among these populations. Embryos were reared under two experimental conditions: a low temperature regime at 4 °C until eyed-stage and 10 °C until the end of embryonic development and a high temperature regime with a constant temperature of 10 °C throughout embryonic development. Significant variations among populations and population × temperature interactions were observed for embryo survival, incubation time and length. QST was higher than FST in all but one comparison suggesting an important effect of divergent selection. QST was also higher under the high-temperature treatment than at low temperature for length and survival due to a higher variance among populations under the stressful warmer treatment. Interestingly, heritability was lower for survival under high temperature in relation to a lower additive genetic variance under that treatment. Overall, these results reveal an adaptive divergence in thermal plasticity in embryonic life stages of Atlantic salmon suggesting that salmon populations may differentially respond to temperature variations induced by climate change. These results also suggest that changes in temperature may alter not only the adaptive potential of natural populations but also the selection regimes among them.


Assuntos
Salmo salar/embriologia , Temperatura , Animais , Mudança Climática , Temperatura Baixa , Embrião não Mamífero , Desenvolvimento Embrionário , Temperatura Alta
3.
Heredity (Edinb) ; 117(1): 42-50, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27118155

RESUMO

Effective population size (Ne) is a measure of genetic drift and is thus a central parameter in evolution, conservation genetics and invasion biology. Interestingly, in native marine species, Ne is typically several orders of magnitude lower than the census size. This pattern has often been explained by high fecundity, variation in reproductive success and pronounced early mortality, resulting in genetic drift across generations. Data documenting genetic drift and/or Ne in marine invasive species are, however, still scarce. We examined the importance of genetic drift in the invasive species Crepidula fornicata by genotyping 681 juveniles sampled during each annual recruitment peak over nine consecutive years in the Bay of Morlaix (Brittany, France). Observed variations in genetic diversity were partially explained by variation in recruitment intensity. In addition, substantial temporal genetic differentiation was documented (that is, genetic drift), and was attributed to nonrandom variance in the reproductive success of different breeding groups across years in the study species. Using a set of single-sample and temporal estimators for Ne, we estimated Ne to be three or four orders of magnitude smaller than the census size (Nc). On one hand, this reduction in Ne relative to Nc appeared congruent with, although slight higher than, values commonly observed in native marine species. Particular life-history traits of this invasive species may play an important role in buffering genetic drift. On the other hand, Ne still remained far below Nc, hence, possibly reducing the efficiency of selection effects.


Assuntos
Gastrópodes/genética , Deriva Genética , Genética Populacional , Animais , Evolução Biológica , França , Frequência do Gene , Variação Genética , Genótipo , Espécies Introduzidas , Repetições de Microssatélites , Densidade Demográfica
4.
Neuroimage ; 98: 118-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24795155

RESUMO

Stereo-electroencephalography (SEEG) is considered as the golden standard for exploring targeted structures during pre-surgical evaluation in drug-resistant partial epilepsy. The depth electrodes, inserted in the brain, consist of several collinear measuring contacts (sensors). Clinical routine analysis of SEEG signals is performed on bipolar montage, providing a focal view of the explored structures, thus eliminating activities of distant sources that propagate through the brain volume. We propose in this paper to exploit the common reference SEEG signals. In this case, the volume propagation information is preserved and electrical source localization (ESL) approaches can be proposed. Current ESL approaches used to localize and estimate the activity of the neural generators are mainly based on surface EEG/MEG signals, but very few studies exist on real SEEG recordings, and the case of equivalent current dipole source localization has not been explored yet in this context. In this study, we investigate the influence of volume conduction model, spatial configuration of SEEG sensors and level of noise on the ESL accuracy, using a realistic simulation setup. Localizations on real SEEG signals recorded during intracerebral electrical stimulations (ICS, known sources) as well as on epileptic interictal spikes are carried out. Our results show that, under certain conditions, a straightforward approach based on an equivalent current dipole model for the source and on simple analytical volume conduction models yields sufficiently precise solutions (below 10mm) of the localization problem. Thus, electrical source imaging using SEEG signals is a promising tool for distant brain source investigation and might be used as a complement to routine visual interpretations.


Assuntos
Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Adulto , Córtex Cerebral/fisiopatologia , Estimulação Elétrica , Fenômenos Eletrofisiológicos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Modelos Neurológicos , Convulsões/fisiopatologia
5.
J Evol Biol ; 25(12): 2596-606, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23107024

RESUMO

Understanding whether populations can adapt to new environmental conditions is a major issue in conservation and evolutionary biology. Aquatic organisms are increasingly exposed to environmental changes linked with human activities in river catchments. For instance, the clogging of bottom substratum by fine sediments is observed in many rivers and usually leads to a decrease in dissolved oxygen concentrations in gravel beds. Such hypoxic stress can alter the development and even be lethal for Atlantic salmon (Salmo salar) embryos that spend their early life into gravel beds. In this study, we used a common garden experiment to compare the responses to hypoxic stress of four genetically differentiated and environmentally contrasted populations. We used factorial crossing designs to measure additive genetic variation of early life-history traits in each population. Embryos were reared under normoxic and hypoxic conditions, and we measured their survival, incubation time and length at the end of embryonic development. Under hypoxic conditions, embryos had a lower survival and hatched later than in normoxic conditions. We found different hypoxia reaction norms among populations, but almost no population effect in both treatments. We also detected significant sire × treatment interactions in most populations and a tendency for heritability values to be lower under stressful conditions. Overall, these results reveal a high degree of phenotypic plasticity in salmon populations that nevertheless differ in their adaptive potential to hypoxia given the distinct reaction norms observed between and within populations.


Assuntos
Variação Genética , Hipóxia/fisiopatologia , Salmo salar/fisiologia , Estresse Fisiológico , Animais , Oceano Atlântico , Evolução Biológica , Feminino , Masculino , Característica Quantitativa Herdável
6.
Res Diagn Interv Imaging ; 3: 100012, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39077379

RESUMO

•The accuracy of ultrasound (US)-guided biopsies of suspicious microcalcifications without mass is similar, or even better than results published in literature with stereotactic-guided biopsies.•When the microcalcifications are visible on ultrasound, there is no loss of chance in performing the biopsy under ultrasound guidance rather than under stereotactic guidance.•US guidance allows access to difficult areas for stereotactic, increases the comfort of the patient, avoids compression and irradiation.

7.
Clin Exp Rheumatol ; 26(2): 234-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18565243

RESUMO

OBJECTIVE: The efficacy of anti-tumour necrosis factor-alpha (TNF-alpha) therapies in rheumatoid arthritis (RA) has been mainly attributed to TNF-alpha neutralisation. Other mechanism as immune cell apoptosis, which is impaired in RA, may also be induced by anti-TNF-alpha therapies. The aim of our study was to investigate whether TNF-alpha inhibitors could induce apoptosis in vitro of the peripheral blood lymphocytes of RA patients. METHODS: Peripheral blood mononuclear cells (PBMC) isolated from 24 patients with RA and 18 healthy donors were incubated with anti-TNF-alpha agents, infliximab or etanercept, in comparison with no agent and including an isotypic control, for 48 hours. Apoptosis was detected and quantified by annexin V labelling of phosphatidylserine externalization using cytofluorometric analysis and compared with PBMC production TNF-alpha in vitro. RESULTS: In healthy donors, induced apoptosis was observed in 0.3% to 3.8% of lymphocytes with both therapies. In RA patients the treatment induced lymphocyte apoptosis in 17 of 24 patients with a percentage of annexin V-positive lymphocytes ranging from 0.1% to 25%. Among these 17 RA patients, a significant in vitro lymphocyte apoptosis (> 4%) was observed in 11 patients (46%) compared with healthy donors (p < 0.01). The variability of the response to anti-TNF-alpha within the RA population was not dependent on TNF-alpha synthesis or disease activity. CONCLUSION: In vitro induction of lymphocyte apoptosis by anti-TNF-alpha was observed in a subgroup of RA patients. Based on these data, it would be of interest to further study the interindividual variations of sensitivity to apoptosis induced by TNF alpha inhibitors in relation to treatment efficacy or resistance observed in RA patients.


Assuntos
Anticorpos Monoclonais/farmacologia , Antirreumáticos/farmacologia , Apoptose/efeitos dos fármacos , Artrite Reumatoide/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/imunologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Células Cultivadas , Etanercepte , Feminino , Humanos , Imunoglobulina G/farmacologia , Técnicas In Vitro , Infliximab , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia
8.
Eur J Clin Microbiol Infect Dis ; 25(11): 687-93, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17024503

RESUMO

The low avidity of immunoglobulin G has been reported to be a useful marker of recent infection with Toxoplasma. Several investigators, however, have published discrepant result on the maturation of avidity over time. The aim of this study was to analyse persistent low avidity of immunoglobulin G in immunocompetent individuals and in pregnant women and how it could interfere in the flowchart of antenatal diagnosis of toxoplasmosis in the latter group. An international literature search was conducted together with a retrospective study of a hospital database. Eleven publications that met the inclusion criteria reported delayed maturation of avidity at a frequency ranging from 0 to 66.6% of the patients. Examination of those publications demonstrated an important heterogeneity in the type of assay used, the calculation of avidity, the cutoff above which avidity was considered to be elevated, and the delay since infection after which indices are expected to be high. In the hospital database, persistent low avidity was found even after a median follow-up period of 6 years. Different factors could interfere with maturation of avidity, such as variations between individuals, the assay system used, and, possibly, the treatment administered. The results of this study clearly demonstrate that, in a pregnant woman, an acute infection cannot be reliably diagnosed solely on the basis of low avidity of immunoglobulin G. Further investigations and standardization of assays are urgently needed. Estimation of the time of infection remains difficult, especially in cases in which the samples are drawn late in pregnancy; the final estimate must be based on several tests repeated at intervals of weeks.


Assuntos
Anticorpos Antiprotozoários , Afinidade de Anticorpos , Imunoglobulina G , Complicações Parasitárias na Gravidez/diagnóstico , Toxoplasmose/diagnóstico , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Doença Crônica , Feminino , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Gravidez , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/parasitologia , Toxoplasmose/imunologia , Toxoplasmose/parasitologia
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