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1.
J Obstet Gynaecol Can ; 46(2): 102233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37820927

RESUMO

OBJECTIVES: Limited studies on the benefits of blastocyst transfer in advanced maternal age (AMA) (≥40 years) have been reported. Our objective was to find whether blastocyst-stage embryo transfer improves pregnancy and live birth rates in women ≥40 years who have 3 or more good-quality cleavage-stage embryos. METHODS: All fresh in vitro fertilization-intracytoplasmic sperm injection cycles performed from January 2020 to December 2021 in AMA women that progressed to transfer were considered for analysis. We compared fresh and cumulative ongoing pregnancy rates in AMA women of those who had a cleavage-stage transfer, while meeting the criteria for extended culture (≥3 high-quality embryos, group 1), and those who underwent blastocyst transfer (group 2). Demographic parameters, stimulation, embryology, fresh and cumulative ongoing pregnancy rates, and clinical miscarriage rates were compared. RESULTS: During the study period, 255 cycles were analyzed including group 1 (n = 99) and group 2 (n = 156). Group 1 participants were older and had a greater number of embryos for transfer. Fresh and cumulative ongoing pregnancy rates per transfer were higher in group 2 compared to group 1 (23.4% vs. 13.1%, P = 0.04; 25.5% vs. 14.1%, P = 0.03), while overall miscarriage rates were higher in group 1 than group 2 (51.7% vs. 25%, P = 0.01). CONCLUSIONS: Blastocyst culture provides a benefit to AMA women who have at least 3 good-quality embryos on day 3 resulting in significantly higher fresh and cumulative ongoing pregnancy rates and lower miscarriage compared to cleavage-stage transfers.


Assuntos
Aborto Espontâneo , Masculino , Gravidez , Feminino , Humanos , Adulto , Idade Materna , Aborto Espontâneo/epidemiologia , Estudos Retrospectivos , Sêmen , Transferência Embrionária/métodos , Fertilização in vitro , Taxa de Gravidez
2.
Microb Pathog ; 156: 104917, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33940135

RESUMO

The obligate intracellular bacterium Chlamydia trachomatis is an important human pathogen with a biphasic developmental cycle comprised of an infectious elementary body (EB) and a replicative reticulate body (RB). Whereas σ66, the primary sigma factor, is necessary for transcription of most chlamydial genes throughout the developmental cycle, σ28 is required for expression of some late genes. We previously showed that the Chlamydia-specific transcription factor GrgA physically interacts with both of these sigma factors and activates transcription from σ66- and σ28-dependent promoters in vitro. Here, we investigated the organismal functions of GrgA. We show that overexpression of GrgA slows EB-to-RB conversion, decreases RB proliferation, and reduces progeny EB production. In contrast, overexpression of a GrgA variant without the σ28-binding domain shows significantly less severe inhibitory effects, while overexpression of a variant without the σ66-binding domain demonstrates no adverse effects. These findings indicate that GrgA plays important roles in the expression regulation of both σ66-dependent genes and σ28-dependent genes during the chlamydial developmental cycle.


Assuntos
Chlamydia trachomatis , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chlamydia trachomatis/genética , Humanos , Fator sigma/genética , Fator sigma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 629-632, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018066

RESUMO

Studying the neural correlates of sleep can lead to revelations in our understanding of sleep and its interplay with different neurological disorders. Sleep research relies on manual annotation of sleep stages based on rules developed for healthy adults. Automating sleep stage annotation can expedite sleep research and enable us to better understand atypical sleep patterns. Our goal was to create a fully unsupervised approach to label sleep and wake states in human electro-corticography (ECoG) data from epilepsy patients. Here, we demonstrate that with continuous data from a single ECoG electrode, hidden semi-Markov models (HSMM) perform best in classifying sleep/wake states without excessive transitions, with a mean accuracy (n=4) of 85.2% compared to using K-means clustering (72.2%) and hidden Markov models (81.5%). Our results confirm that HSMMs produce meaningful labels for ECoG data and establish the groundwork to apply this model to cluster sleep stages and potentially other behavioral states.


Assuntos
Eletrocorticografia , Vigília , Adulto , Humanos , Polissonografia , Sono , Fases do Sono
4.
J Neurotrauma ; 36(2): 264-274, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29901414

RESUMO

This study longitudinally assessed 10- to 14-year-old patients with sports and recreational concussion (n = 22) who remained symptomatic 3 to 4weeks post-injury compared with typically developing controls (n = 24). Examination by multi-modal magnetic resonance imaging (MRI) and multi-domain clinical outcome measures was completed at 1-month and 6-months post-injury. Concussion patients showed evidence of improvement by 6-month follow-up in domains of cognitive function, whereas measures of psychological health were less resolved with patients exhibiting sustained symptoms of depression, behavior impairment, and concussion symptoms. Quantitative neuroimaging measures identified measures indicative of chronic injury with regional reductions observed by both volumetric segmentation and white matter fractional anisotropy (FA) from diffusion tensor imaging (DTI). Volumetric reductions (p < 0.01) were observed in the middle anterior and posterior portions of the corpus callosum, and right caudal anterior cingulate cortex of patients, although none held after strict correction. Examination of the FA data identified significant reductions in the left middle frontal gyrus white matter (p = 0.0003). Linear regression analysis on the 6-month depression outcome variable using the initial clinical, demographic, and imaging measures identified the top predictive models to include concussion diagnosis, and initial symptoms of depression, concussion symptoms, and sleep impairment with additional contribution from other measures of mental health, behavior impairment, and quality of life depending on the model (adjusted r-squared = 0.69 indicating strong predictive ability). This study supports further inclusion of mental health rehabilitation and imaging supplementing traditional cognitive rehabilitation strategies employed in these young athletes.


Assuntos
Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico por imagem , Adolescente , Atletas , Traumatismos em Atletas/complicações , Traumatismos em Atletas/diagnóstico por imagem , Criança , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Imagem de Tensor de Difusão , Feminino , Humanos , Estudos Longitudinais , Masculino , Neuroimagem
5.
J Head Trauma Rehabil ; 33(6): E1-E10, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29385018

RESUMO

OBJECTIVE: Prior work suggests that younger athletes may be more vulnerable to postconcussive syndrome. We investigated measures of clinical outcome and quantitative volumetric imaging in 10- to 14-year-old adolescent athletes to better understand the impact of concussion on this younger population. SETTING: Outpatient clinics. PARTICIPANTS: Ten- to 14-year-old symptomatic pediatric sports concussion patients and typically developing active controls. DESIGN: Prospective, observational multiclinic study. MAIN MEASURES: Demographics, magnetic resonance imaging, clinical assessments (neurocognitive function, postconcussive symptoms, mental health symptoms, quality of life). RESULTS: Neuropsychological performance was comparable between groups while symptoms of mental health were discriminating and comprised the top regression model describing factors related to overall health behavior impairment. Concussion patients had smaller total brain volume as well as total intracranial volume in comparison with controls even though there was no difference on measures of natural development (age, height, weight, education, gender, and handedness). CONCLUSIONS: Findings indicate that 10- to 14-year-old concussion patients symptomatic at 1 month more likely exhibit mental health symptoms impairing health behavior than cognitive dysfunction. There may be a vulnerability for those with smaller brain volumes at the time of the exposure. The study provides new data to support further investigation into risk factors for prolonged symptoms in this younger athlete population.


Assuntos
Traumatismos em Atletas/diagnóstico por imagem , Concussão Encefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Adolescente , Ansiedade/diagnóstico , Traumatismos em Atletas/psicologia , Concussão Encefálica/psicologia , Estudos de Casos e Controles , Criança , Depressão/diagnóstico , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Testes Neuropsicológicos , Estudos Prospectivos , Qualidade de Vida
6.
Neuroimage Clin ; 14: 371-378, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28243574

RESUMO

Current imaging diagnostic techniques are often insensitive to the underlying pathological changes following mild traumatic brain injury (TBI) or concussion so much so that the explicit definition of these uncomplicated mild brain injuries includes the absence of radiological findings. In the US military, this is complicated by the natural tendency of service members to down play symptoms for fear of removal from their unit particularly in combat making it challenging for clinicians to definitively diagnose and determine course of treatment. Questions remain regarding the long-term impact of these war-time brain injuries. The objective of the current study was to evaluate the long-term imaging sequelae of blast concussion in active-duty US military and leverage previous longitudinal data collected in these same patients to identify predictors of sustained DTI signal change indicative of chronic neurodegeneration. In total, 50 blast TBI and 44 combat-deployed controls were evaluated at this 5-year follow up by advanced neuroimaging techniques including diffusion tensor imaging and quantitative volumetry. While cross-sectional analysis of regions of white matter on DTI images did not reveal significant differences across groups after statistical correction, an approach flexible to the heterogeneity of brain injury at the single-subject level identified 74% of the concussive blast TBI cohort to have reductions in fractional anisotropy indicative of chronic brain injury. Logistic regression leveraging clinical and demographic data collected in the acute/sub-acute and 1-year follow up to determine predictors of these long-term imaging changes determined that brain injury diagnosis, older age, verbal memory and verbal fluency best predicted the presence of DTI abnormalities 5 years post injury with an AUC of 0.78 indicating good prediction strength. These results provide supporting evidence for the evolution not resolution of this brain injury pathology, adding to the growing body of literature describing imaging signatures of chronic neurodegeneration even after mild TBI and concussion.


Assuntos
Traumatismos por Explosões/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Adulto , Anisotropia , Progressão da Doença , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Logísticos , Estudos Longitudinais , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Estatísticas não Paramétricas , Adulto Jovem
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