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1.
Neurobiol Learn Mem ; 206: 107866, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37995802

RESUMO

Classically interpreted as a competition between opposite memories (A vs B), anterograde interference (AI) also emerges in the absence of competing memories (A vs A), suggesting that mechanisms other than those involved in memory competition contribute to AI. To investigate this, we tested the hypothesis that extending motor practice would enhance a first memory, but come at the cost of reduced learning capabilities when subsequently exposed to a second learning session of the same task. Based on converging biological evidence, AI was expected to depend upon the degree of extended practice of the initial exposure. During a first Session, four conditions were carried out where participants (n = 24) adapted to a gradually introduced -20° visual deviation while the extent of the initial exposure was manipulated by varying the duration or type of the performance asymptote. Specifically, the performance asymptote at -20° was either Short (40 trials), Moderate (160 trials), Long (320 trials), or absent due to continuously changing perturbations around the mean of -20° (Jagged; 160 trials). After a 2-min interval, participants re-adapted to the same (-20°) visual deviation, which was meant to probe the effect of extended practice in the first Session on the learning capabilities of a second identical memory (A vs A). The results first confirmed that the duration of exposure in the first Session enhanced immediate aftereffects in the Moderate, Long, and Jagged conditions as compared to the Short condition, suggesting that extended practice enhanced retention of the first memory. When comparing the second Session to the first one, results revealed a different pattern of re-adaptation depending on the duration of initial exposure: in the Short condition, there was evidence for facilitated re-adaptation and similar aftereffects. However, in the Moderate, Long and Jagged conditions, re-adaptation was similar and aftereffects were impaired, suggestive of AI. This suggests that extended practice initially enhances memory formation, but comes at the cost of reduced subsequent learning capabilities. One possibility is that AI occurs because extended practice induces the emergence of network-specific homeostatic constraints, which limit subsequent neuroplastic and learning capabilities in the same neural network.


Assuntos
Adaptação Fisiológica , Desempenho Psicomotor , Humanos , Aprendizagem
2.
Neurobiol Learn Mem ; 185: 107532, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34592470

RESUMO

While the effects of rewards on memory appear well documented, the effects of punishments remain uncertain. Based on neuroimaging data, this study tested the hypothesis that, as compared to a neutral condition, a context allowing successful punishment avoidance would enhance memory to a similar extent as rewards. In a fully within-subject and counter-balanced design, participants (n = 18) took part in 3 distinct learning sessions during which the delivery of performance-contingent monetary punishments and rewards was manipulated. Specifically, participants had to reach towards visual targets while compensating for a gradually introduced visual deviation. Accuracy at achieving targets was either punished (Hit: "+0$"; Miss: "-0.5$), rewarded (Hit: "+0.5$"; Miss: "-0$"), or associated with neutral binary feedback (Hit: "Hit"; Miss: "Miss"). Retention was assessed through reach aftereffects both immediately and 24 h after initial acquisition. The results disconfirmed the hypothesis by showing that the punishment and reward learning sessions both impaired retention as compared to the neutral session, suggesting that both types of incentives similarly impaired memory formation and consolidation. Two alternative but complementary interpretations are discussed. One interpretation is that the presence of punishments and rewards induced a negative learning context, which - based on neurobiological data - could have been sufficient to interfere with memory formation and consolidation. Another interpretation is that punishments and rewards emphasized the disrupting effects of target hits on implicit learning processes, therefore yielding retention impairments. Altogether, these results suggest that incentives can have counter-productive effects on memory.


Assuntos
Desempenho Psicomotor , Punição , Retenção Psicológica , Recompensa , Estimulação Acústica , Fenômenos Biomecânicos , Feminino , Feedback Formativo , Humanos , Masculino , Consolidação da Memória/fisiologia , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Punição/psicologia , Retenção Psicológica/fisiologia , Adulto Jovem
3.
Gynecol Obstet Fertil Senol ; 49(6): 529-537, 2021 06.
Artigo em Francês | MEDLINE | ID: mdl-33434753

RESUMO

OBJECTIVE: To assess the impact of hepatitis B virus (HBV) infection in women on in vitro fertilization (IVF) outcomes. METHODS: An observational monocentric case-control cohort study conducted between 2012 and 2019 compared the outcomes of the first cycle of IVF between 64 woman infected with HBV and 128 seronegative controls. Frozen embryos transfers made within 18 months of the puncture were included. The exclusion criteria were severe infections, viral co-infection in women, any viral infection in their spouse, or lack of fresh embryo transfer. The matching was performed according to age, primary infertility or secondary, conventional or intracytoplasmic injection IVF technique and date of attempt. The main analysis focused on cumulative live births rates (LBR). RESULTS: The clinical and ovarian stimulation characteristics were comparable except for a longer period of infertility in the HBV group. The LBR in the HBV group, when compared to controls, was not different after transfer of fresh (14.06 vs. 25.00% P=0.08) or frozen embryos (4.17 vs. 18.92% P=0.08), but significantly decreased in cumulative analysis (15.63 vs. 35.94% P=0.003). HBV infection was negatively associated with LBR in multivariate analysis OR=0.38 (95% CI 0.14-0.92) P<0.05. The implantation rate was lower in the HBV group versus controls, in fresh (14.89 vs. 27.72% P=0.02) and frozen (3.03 vs. 21.65% P=0.01) embryo transfers. CONCLUSION: This study suggests a negative impact of HBV infection in women on the cumulative LBR after IVF.


Assuntos
Vírus da Hepatite B , Nascido Vivo , Estudos de Casos e Controles , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
4.
Proc Biol Sci ; 288(1942): 20202556, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33434470

RESUMO

Anterograde interference emerges when two differing tasks are learned in close temporal proximity, an effect repeatedly attributed to a competition between differing task memories. However, recent development alternatively suggests that initial learning may trigger a refractory period that occludes neuroplasticity and impairs subsequent learning, consequently mediating interference independently of memory competition. Accordingly, this study tested the hypothesis that interference can emerge when the same motor task is being learned twice, that is when competition between memories is prevented. In a first experiment, the inter-session interval (ISI) between two identical motor learning sessions was manipulated to be 2 min, 1 h or 24 h. Results revealed that retention of the second session was impaired as compared to the first one when the ISI was 2 min but not when it was 1 h or 24 h, indicating a time-dependent process. Results from a second experiment replicated those of the first one and revealed that adding a third motor learning session with a 2 min ISI further impaired retention, indicating a dose-dependent process. Results from a third experiment revealed that the retention impairments did not take place when a learning session was preceded by simple rehearsal of the motor task without concurrent learning, thus ruling out fatigue and confirming that retention is impaired specifically when preceded by a learning session. Altogether, the present results suggest that competing memories is not the sole mechanism mediating anterograde interference and introduce the possibility that a time- and dose-dependent refractory period-independent of fatigue-also contributes to its emergence. One possibility is that learning transiently perturbs the homeostasis of learning-related neuronal substrates. Introducing additional learning when homeostasis is still perturbed may not only impair performance improvements, but also memory formation.


Assuntos
Adaptação Fisiológica , Desempenho Psicomotor , Aprendizagem , Memória , Destreza Motora
7.
Gynecol Obstet Fertil Senol ; 47(4): 362-369, 2019 04.
Artigo em Francês | MEDLINE | ID: mdl-30753900

RESUMO

With the use of antiretroviral therapy, HIV transmission from mother to fetus and between sexual partners has been significantly reduced, successively allowing pregnancy, then assisted reproductive technologies, and targeted unprotected sex among couples living with HIV. Since first French Morlat report in 2013, natural procreation is now possible under certain conditions for these couples living with HIV and the use of assisted reproductive technologies is increasingly limited to the treatment of infertility. While the results of intrauterine insemination seem satisfactory for serodiscordant couples living with HIV, in vitro fertilization results appear to be unfavorable when the woman is infected with HIV. In vitro fertilization results appear to be comparable to those in general population when only the man is infected with HIV. It can be assumed that ovaries are impacted by the treatment and/or the HIV in infected women.


Assuntos
Infecções por HIV/prevenção & controle , Infertilidade/terapia , Contraindicações de Procedimentos , Feminino , França , Infecções por HIV/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Masculino , Técnicas de Reprodução Assistida , Sêmen/virologia
8.
J Gynecol Obstet Hum Reprod ; 48(4): 235-239, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29908951

RESUMO

INTRODUCTION: The management of posterior deep endometriosis is not consensual. This is due to a great heterogeneity of data from the literature. Many series were small and overall, predictors of pregnancy were not all included and analyzed by multivariate analysis. We conducted this study to evaluate the factors associated with pregnancy during the first two in vitro fertilization (IVF) attempts in infertile women with posterior deep endometriosis. MATERIAL AND METHODS: 230 women were included in this retrospective observational study, between January 1st, 2007 and September 30th, 2013, at the University Hospital of Lille. A large set of variables were recorded and their association with the chance of pregnancy was analyzed by multivariate analysis (MVA), including patients' features, endometriosis items, surgery procedures and IVF data. RESULTS: After 2 IVF attempts, 48.7% of the 230 women achieved a pregnancy, including 39.1% of ongoing pregnancies. Logistic regression analysis retained five variables significantly associated to the chance of pregnancy: oocyte retrieval number (OR=0.468 (0.296-0.739) p=0.001), age (OR=0.888 (0.811-0.974) p=0.011), single embryo transfer number (OR=1.494 (1.036-2.153) p=0.031), presence of a recto-uterine nodule (OR=0.454 (0.235-0.877) p=0.019) and IVF technique (OR=0.509 (0.272-0.951) p=0.034). CONCLUSION: The presence of a recto uterine nodule is associated with a lower chance of pregnancy after IVF. It has to be checked by prospective studies whether the finding of a recto-uterine nodule whose pejorative effect has not been reported so far should encourage to perform surgery before IVF in patients with deep endometriosis.


Assuntos
Endometriose/complicações , Fertilização in vitro , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Adulto , Endometriose/patologia , Endometriose/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Recuperação de Oócitos , Doenças Peritoneais/complicações , Doenças Peritoneais/patologia , Doenças Peritoneais/cirurgia , Gravidez , Taxa de Gravidez , Doenças Retais/complicações , Doenças Retais/patologia , Doenças Retais/cirurgia , Estudos Retrospectivos , Transferência de Embrião Único , Resultado do Tratamento , Doenças Uterinas/complicações , Doenças Uterinas/patologia , Doenças Uterinas/cirurgia , Doenças Vaginais/complicações , Doenças Vaginais/patologia , Doenças Vaginais/cirurgia
11.
Clin Exp Obstet Gynecol ; 43(6): 887-888, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29944245

RESUMO

When bulky fibroids are discovered during pregnancy, they can become acutely complicated. The question of their resection thus arises. The authors report a case of a woman who was diagnosed at eight weeks' gestation by ultrasound and then by MRI, with a uterine fibroma measuring 22x12x15 cm.


Assuntos
Leiomioma/cirurgia , Complicações Neoplásicas na Gravidez/cirurgia , Miomectomia Uterina/métodos , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/patologia , Imageamento por Ressonância Magnética , Gravidez , Primeiro Trimestre da Gravidez , Carga Tumoral , Ultrassonografia , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/patologia
12.
Eur J Obstet Gynecol Reprod Biol ; 197: 41-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26704016

RESUMO

Simulation training is an appealing and useful addition to health facilities. Simulation centers are organized to maximize network resources. Simulation training is used for certification or recertification of health professionals and is now an integral part of the methods used in continuing professional development. Simulation has played a unique role in obstetrics. This article is a narrative review describing the different types of childbirth simulators, whether anatomical, virtual, or instrumented. The article identifies the role of each simulator in the training of obstetricians and the role of these instruments in simulation centers.


Assuntos
Parto Obstétrico/educação , Obstetrícia/educação , Parto , Treinamento por Simulação , Simulação por Computador , Feminino , Humanos , Modelos Anatômicos , Gravidez
13.
Gynecol Obstet Fertil ; 43(2): 109-16, 2015 Feb.
Artigo em Francês | MEDLINE | ID: mdl-25595945

RESUMO

OBJECTIVE: Does surgery for deep infiltrating endometriosis (DIE) before in vitro fertilization (IVF) improve pregnancy and birth rate? PATIENTS AND METHODS: Cohort study of 177 consecutive patients with DIE related infertility and receiving IVF. Patients were divided into 3 groups according to surgical management decided during multidisciplinary team meeting. Group no surgery (NS) (n=65), group complete surgery (CS) with complete resection of all lesions (n=49) and group incomplete surgery (IS) with gestures improving ovaries accessibility for IVF and/or facilitating embryonic implantation (n=63). Pre-surgery clinical, MRI lesion locations, and history of IVF characteristics were analyzed with logistic regression. RESULTS: There was no significant difference in general and IVF characteristics and in the severity of endometriosis among the three groups (P=0.43). Overall pregnancy and birth rates after IVF were 45.8% and 33.3%, respectively and were not different among the 3 groups (P=0.59 and P=0.49). Four major complications during oocytes retrievals were observed in NS group, one in IS group and none in CS group. Presence of an inter-utero-rectal lesion at MRI decreased the rate of pregnancy (OR=0.49 [0.25, 0.97]). DISCUSSION AND CONCLUSIONS: Surgery for deep infiltrating endometriosis does not improve pregnancy and birth rates before IVF. This inter-utero-rectal extensive lesion might explain IVF failures by ovarian difficult access and difficulties in embryonic transfers. Further studies should explore the impact of surgical excision of inter-utero-rectal lesion on oocyte retrieval and embryonic transfer.


Assuntos
Coeficiente de Natalidade , Endometriose/cirurgia , Fertilização in vitro , Taxa de Gravidez , Adulto , Estudos de Coortes , Endometriose/patologia , Feminino , Humanos , Infertilidade Feminina/terapia , Gravidez
14.
Int Urogynecol J ; 26(4): 497-504, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25227746

RESUMO

INTRODUCTION AND HYPOTHESIS: We created a pregnant woman pelvic model to perform a simulation of delivery to understand the pathophysiology of urogenital prolapse by studying the constraints on the pelvic components (muscles, ligaments, pelvic organs) during childbirth. These simulations will also provide valuable tools to understand and teach obstetrical mechanics. METHODS: We built a numerical model of the pelvic system from a term pregnant woman, using the finite element method on a mesh built from magnetic resonance images of a nulliparous pregnant woman. Mechanical properties of pelvic tissues already determined by the team were adapted to account for pregnancy. RESULTS: The system allows delivery to be simulated. When a fetal head at the 50th percentile for the term goes through the pelvic system, uterosacral ligaments undergo a deformation of around 30 %. Uterosacral ligaments are the major pelvic sustaining structures, their lesion may be a potential cause of urogenital prolapse. We built a model of childbirth as a function of pregnancy term by varying volumes of fetal head and uterus. The impact on uterosacral ligaments is higher when the fetal head is larger. CONCLUSIONS: Our modelling is rather complete considering that it involves many organs including ligaments. It allows us to analyse the effect of childbirth on uterosacral ligaments and to understand how they impact on pelvic statics. First results are promising, but optimisation and future simulations will be needed. We also plan to simulate various delivery scenarios (cephalic, breech presentation, instrumental extraction), which will be useful to study perineal lesions and also to teach obstetrical mechanics.


Assuntos
Cabeça/anatomia & histologia , Ligamentos/fisiologia , Modelos Biológicos , Pelve/fisiologia , Gravidez/fisiologia , Nascimento a Termo/fisiologia , Fenômenos Biomecânicos , Simulação por Computador , Feminino , Feto/anatomia & histologia , Análise de Elementos Finitos , Humanos , Tamanho do Órgão , Prolapso de Órgão Pélvico/etiologia
15.
Public Health ; 128(11): 985-92, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25443100

RESUMO

OBJECTIVES: This study evaluates the prevalence of Multiple Comorbid Chronic Disease (MCCD) within homeless and non-homeless Veterans and the association between MCCD and inpatient medical care. METHODS: All individuals seen in the VA North Texas Health Care System between October 1, 2009 and September 30, 2010 (n = 102,034) were evaluated. Homelessness during the year and the number of common chronic diseases were evaluated for an association with likelihood of medical and psychiatric hospitalizations, bed days of care, inpatient substance treatment, rehabilitation admissions, and emergency department visits. RESULTS: Homeless Veterans had higher all-cause mortality rates and rates of use of almost all resources after controlling for chronic disease burden using the Charlson Comorbidity Index, psychiatric illnesses, substance use disorders, and demographic variables. CONCLUSIONS: Homelessness Veterans are vulnerable to a high use of resources and mortality, independent of medical and psychiatric conditions. This finding should focus additional attention on reducing homelessness.


Assuntos
Doença Crônica/epidemiologia , Serviços de Saúde/estatística & dados numéricos , Pessoas Mal Alojadas/estatística & dados numéricos , Saúde dos Veteranos/estatística & dados numéricos , Veteranos/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Texas/epidemiologia , Adulto Jovem
16.
Genes Brain Behav ; 13(2): 127-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24308542

RESUMO

The neurocognitive and behavioral profile of individuals with 47,XYY is increasingly documented; however, very little is known about the effect of a supernumerary Y-chromosome on brain development. Establishing the neural phenotype associated with 47,XYY may prove valuable in clarifying the role of Y-chromosome gene dosage effects, a potential factor in several neuropsychiatric disorders that show a prevalence bias toward males, including autism spectrum disorders. Here, we investigated brain structure in 10 young boys with 47,XYY and 10 age-matched healthy controls by combining voxel-based morphometry (VBM) and surface-based morphometry (SBM). The VBM results show the existence of altered gray matter volume (GMV) in the insular and parietal regions of 47,XYY relative to controls, changes that were paralleled by extensive modifications in white matter (WM) bilaterally in the frontal and superior parietal lobes. The SBM analyses corroborated these findings and revealed the presence of abnormal surface area and cortical thinning in regions with abnormal GMV and WMV. Overall, these preliminary results demonstrate a significant impact of a supernumerary Y-chromosome on brain development, provide a neural basis for the motor, speech and behavior regulation difficulties associated with 47,XYY and may relate to sexual dimorphism in these areas.


Assuntos
Encéfalo/patologia , Transtornos dos Cromossomos Sexuais/patologia , Cariótipo XYY/patologia , Adolescente , Estudos de Casos e Controles , Criança , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos dos Cromossomos Sexuais/diagnóstico , Cariótipo XYY/diagnóstico
18.
J Gynecol Obstet Biol Reprod (Paris) ; 41(8): 788-802, 2012 Dec.
Artigo em Francês | MEDLINE | ID: mdl-23142358

RESUMO

OBJECTIVES: To evaluate the benefits and risks of labor induction in patients previously delivered by at least one low transverse cesarean section. To define how labor should be managed in patients attempting a vaginal birth after cesarean section (VBAC). METHODS: A literature search was performed using the Pubmed(®) and Cochrane(®) databases. Foreign societies guidelines were also consulted. RESULTS: Labor induction is associated with an increased risk of uterine rupture that could be estimated at 1% with oxytocine and 2% with vaginal prostaglandins (Level 2). Mechanical methods have been insufficiently studied. Misoprostol seems to dramatically increase the risk of uterine rupture (Level 3). The routine use of intrauterine pressure catheter does not prevent uterine rupture (Professional agreement). A moderate increase of uterine rupture was also found with augmentation (Level 3). The risk of uterine rupture increases when cervical dilatation is arrested for 3 hours or more when a good uterine dynamic is obtained (Professional agreement). The use of epidural analgesia should be encouraged (Grade C). Routine digital exploration of the uterine scare postpartum is not necessary (Grade C). CONCLUSION: Women attempting a VBAC should be aware of the modalities of labor management. When labor induction is warranted, women should also be informed of the indication and the increased risk of uterine rupture. The choice of labor induction method should take into consideration maternal and obstetrical characteristics.


Assuntos
Cicatriz/complicações , Trabalho de Parto Induzido/efeitos adversos , Trabalho de Parto Induzido/métodos , Complicações do Trabalho de Parto , Doenças Uterinas/complicações , Ruptura Uterina , Analgesia Epidural , Feminino , Humanos , Primeira Fase do Trabalho de Parto , Misoprostol/efeitos adversos , Ocitócicos/efeitos adversos , Ocitocina/efeitos adversos , Gravidez , Prostaglandinas/efeitos adversos , Fatores de Risco , Ruptura Uterina/epidemiologia , Ruptura Uterina/etiologia , Nascimento Vaginal Após Cesárea/efeitos adversos
20.
Bull Environ Contam Toxicol ; 88(3): 482-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22205472

RESUMO

A regional air assessment was performed to characterize volatile natural isothiocyanate (NITC) compounds in air during soil incorporation of mustard cover crops in Washington State. Field air sampling and analytical methods were developed specific to three NITCs known to be present in air at appreciable concentrations during/after field incorporation. The maximum observed concentrations in air for the allyl, benzyl, and phenethyl isothiocyanates were respectively 188, 6.1, and 0.7 µg m(-3) during mustard incorporation. Based on limited inhalation toxicity information, airborne NITC concentrations did not appear to pose an acute human inhalation exposure concern to field operators and bystanders.


Assuntos
Poluentes Atmosféricos/análise , Isotiocianatos/análise , Mostardeira/metabolismo , Agricultura/métodos , Poluentes Atmosféricos/metabolismo , Monitoramento Ambiental , Humanos , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Isotiocianatos/metabolismo , Mostardeira/crescimento & desenvolvimento , Poluentes do Solo/análise , Poluentes do Solo/metabolismo
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