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1.
AJOG Glob Rep ; 3(3): 100209, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37645653

RESUMO

BACKGROUND: Preimplantation genetic testing for aneuploidy has been proven to be effective in determining the embryo's chromosomal or ploidy status. The test requires a biopsy of embryonic cells on day 3, 5, or 6 from which complete information on the chromosomes would be obtained. The main drawbacks of preimplantation genetic testing for aneuploidy include its relatively invasive approach and the lack of research studies on the long-term effects of preimplantation genetic testing for aneuploidy. OBJECTIVE: Computer-assisted predictive modeling through machine learning and deep learning algorithms has been proposed to minimize the use of invasive preimplantation genetic testing for aneuploidy. The capability to predict morphologic characteristics of embryo ploidy status creates a meaningful support system for decision-making before further treatment. STUDY DESIGN: Image processing is a component in developing a predictive model specialized in image classification through which a model is able to differentiate images based on unique features. Image processing is obtained through image augmentation to capture segmented embryos and perform feature extraction. Furthermore, multiple machine learning and deep learning algorithms were used to create prediction-based modeling, and all of the prediction models undergo similar model performance assessments to determine the best model prediction algorithm. RESULTS: An efficient artificial intelligence model that can predict embryo ploidy status was developed using image processing through a histogram of oriented gradient and then followed by principal component analysis. The gradient boosting algorithm showed an advantage against other algorithms and yielded an accuracy of 0.74, an aneuploid precision of 0.83, and an aneuploid predictive value (recall) of 0.84. CONCLUSION: This research study proved that machine-assisted technology perceives the embryo differently than human observation and determined that further research on in vitro fertilization is needed. The study finding serves as a basis for developing a better computer-assisted prediction model.

2.
Neurochem Int ; 112: 134-145, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29032009

RESUMO

Development of manganism (also known as manganese neurotoxicity) is a major complication of manganese exposure in which neurological dysfunction is linked to accumulation of the metal in brain. Due to neuronal cell death in basal ganglia structures, particularly the globus pallidus, functional recovery is limited. Bearing a resemblance to Parkinson's disease, effective treatment for manganism is currently limited. However, the rapidly developing field of stem cell research offers new hope for the treatment of illnesses in which neurodegeneration is a major feature. The first part of this review will focus on the clinical features and pathophysiology of cerebral damage resulting from exposure to manganese, including the role of astrocytes, disruption of energy metabolism, involvement of oxidative stress, excitotoxicity, and inflammation, with the second part exploring how stem cells may provide an important therapeutic strategy for patients with this major neurologic disorder.


Assuntos
Intoxicação por Manganês/terapia , Estresse Oxidativo/fisiologia , Transplante de Células-Tronco/métodos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Intoxicação por Manganês/metabolismo , Transplante de Células-Tronco/tendências , Resultado do Tratamento
3.
Neurosci Lett ; 642: 163-167, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28109775

RESUMO

Recent clinical trials suggest that patients with myelofibrosis can develop Wernicke's encephalopathy (WE) when treated with fedratinib, a specific Janus kinase-2 (JAK-2) inhibitor. To investigate this issue, we have examined (1) if fedratinib can produce or alter the course of this disorder, (2) its effects on thiamine-dependent enzyme activity and thiamine status, and (3) its influence on the uptake of thiamine. Animals administered fedratinib for 28days at a comparable dose used to treat human cases of myelofibrosis showed no evidence of clinical signs of thiamine deficiency (TD). Rats treated with a combination of fedratinib and TD exhibited no neurological differences in their progress to the symptomatic stage when compared to thiamine-deficient animals only. Treatment with the JAK-2 inhibitor did not compromise erythrocyte transketolase activity, and thiamine status was not affected in a major way unlike animals with TD. In addition, treatment of cultured astrocytes with fedratinib did not diminish the uptake of thiamine into these cells. Our findings suggest that treatment with fedratinib does not lead to or alter the progress of TD, and do not support the notion that administration of this JAK-2 inhibitor directly results in the development of WE due to inhibition of thiamine transport. Known adverse effects of fedratinib involving compromised gastrointestinal function may be an important indirect contributing factor to previously reported cases of WE in patients with myelofibrosis.


Assuntos
Janus Quinase 2/antagonistas & inibidores , Pirrolidinas , Sulfonamidas , Deficiência de Tiamina/induzido quimicamente , Encefalopatia de Wernicke/induzido quimicamente , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Tiamina/sangue , Deficiência de Tiamina/sangue
4.
Metab Brain Dis ; 29(4): 1061-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24929329

RESUMO

Thiamine deficiency (TD) is the underlying cause of Wernicke's encephalopathy (WE), an acute neurological disorder characterized by structural damage to key periventricular structures in the brain. Increasing evidence suggests these focal histological lesions may be representative of a gliopathy in which astrocyte-related changes are a major feature of the disorder. These changes include a loss of the glutamate transporters GLT-1 and GLAST concomitant with elevated interstitial glutamate levels, lowered brain pH associated with increased lactate production, decreased levels of GFAP, reduction in the levels of glutamine synthetase, swelling, alterations in levels of aquaporin-4, and disruption of the blood-brain barrier. This review focusses on how these manifestations contribute to the pathophysiology of TD and possibly WE.


Assuntos
Astrócitos/fisiologia , Deficiência de Tiamina/fisiopatologia , Sistema X-AG de Transporte de Aminoácidos/fisiologia , Animais , Transporte Biológico , Barreira Hematoencefálica , Encéfalo/patologia , Modelos Animais de Doenças , Transportador 2 de Aminoácido Excitatório/fisiologia , Ácido Glutâmico/metabolismo , Humanos , Complexo Cetoglutarato Desidrogenase/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo , Piritiamina/toxicidade , Deficiência de Tiamina/induzido quimicamente , Deficiência de Tiamina/metabolismo , Encefalopatia de Wernicke/etiologia , Encefalopatia de Wernicke/metabolismo , Encefalopatia de Wernicke/fisiopatologia
5.
Virol J ; 10: 27, 2013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23336976

RESUMO

BACKGROUND: The Minangkabau is one of the major ethnic groups in Indonesia. Previous studies with a limited number of samples have shown a different prevalence of HBV/C in the Minangkabau compared to the Indonesian population in general. The aim of this study was to assess the HBV genotype distribution pattern and the prevalence of pre-S, T1753V and A1762T/G1764A mutations among the Minangkabau HBV carriers. The samples were collected from Padang, West Sumatera and from western Java. Mixed primers for specific genotypes were used to determine the HBV genotype. Pre-S or S genes were amplified, sequenced and aligned with reference sequences from GenBank to derive a phylogenetic tree for subgenotyping. Pre-S genes were also analyzed for mutations. The basal core promoter (BCP) region was amplified and directly sequenced to analyze T1753V and A1762T/G1764A mutations. RESULTS: The predominant HBV genotype among the Minangkabau HBV carriers (n=117) was C (72.6%) followed by B (24.8%) and co-infection with B and C (2.6%). The prevalence of pre-S mutations, including both the pre-S deletion and pre-S2 start codon mutation, was 41.0%, and the T1753V and A1762T/G1764A mutations were found in 51.9% and 71.2% respectively. HBV/C1 was the predominant HBV subgenotype in the Minangkabau HBV carriers, and was found in 66.2%, followed by B3, B7, C8, B2, B9, C2, and C10 (18.3%, 7.0%, 2.8%, 1.4%, 1.4%, 1.4%, and 1.4% respectively). From samples that were found to be co-infected with HBV B and C, two samples were successfully cloned and subgenotyped, including one with mixed subgenotypes of B3 and C1, and another one with mixed subgenotypes of B7, C1, putative intergenotypic of B/A, and C/A. Furthermore, three samples from donors of non-Minangkabau ethnicity from Padang were found to be infected with an intragenotypic recombination form, including a putative recombinant of B8/B3 and B9/B7. CONCLUSION: HBV/C with subgenotype C1 was the predominant HBV genotype among HBV carriers of Minangkabau ethnicity. The prevalence of pre-S, A1762T/G1764A, and T1753V mutations was higher among the Minangkabau compared to Indonesian HBV carriers in general.


Assuntos
Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/epidemiologia , Hepatite B/virologia , Adulto , Portador Sadio/epidemiologia , Portador Sadio/virologia , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Etnicidade , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Indonésia/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Prevalência , Regiões Promotoras Genéticas , Análise de Sequência de DNA
6.
Int J Dev Neurosci ; 28(1): 83-90, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19782125

RESUMO

In the offspring of prenatal stress animals, overactivity and impaired negative feedback regulation of the hypothalamic-pituitary-adrenal axis are consistent finding. However, little was known about how prenatal stress can permanently alter developmental trajectories of pup's brain. Growth-associated protein-43 (GAP-43) is a presynaptic membrane phosphoprotein whose expression increases during developmental events such as axonal outgrowth or remodeling and synaptogenesis. Phosphorylation of GAP-43 by protein kinase C was correlated with enhanced axonal growth and transmitter release. In adult animals, increase of GAP-43 correlated with monoaminergic deficit in neuropsychiatric disorders. The present study examines the effects of repeated maternal restraint stress on the level of GAP-43 in the brain of rat pups. The results showed that prenatal stress significantly increased GAP-43 level in the PFC of rat pup during PND 7-14 as compared to control but not significant difference when observed at PND 21. Increased GAP-43 expression was also observed in the pup's hippocampus during the same postnatal periods. However, when observed at PND 60, pups born from stressed mother showed a significant lower (p<0.001) GAP-43 expression as compare with control group. These changes indicate the direct effect of corticosteroid hormone, since repeated maternal injection with corticosterone (CORT, 40 mg/kg) during GD 14-21 also gave the same results. PND 7-14 is the peak period of synaptogenesis in these brain areas and abnormal axon sprouting and reorganization may lead to a defect in synaptic pruning at later stage of life. The results suggested that maternal stress is harmful to the developing brain and upregulation of GAP-43 indicated a protective mechanism against the toxicity of maternal stress hormone. Prenatal stress alter the normal developmental trajectories in the pup's brain may underlies the mechanism link between early life stress and neuropsychopathology in later life.


Assuntos
Corticosterona/metabolismo , Proteína GAP-43/metabolismo , Hipocampo/metabolismo , Córtex Pré-Frontal/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/metabolismo , Envelhecimento , Animais , Western Blotting , Feminino , Proteína GAP-43/genética , Regulação da Expressão Gênica no Desenvolvimento , Hipocampo/crescimento & desenvolvimento , Imuno-Histoquímica , Masculino , Mães , Córtex Pré-Frontal/crescimento & desenvolvimento , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Restrição Física
7.
Neurosci Lett ; 470(1): 24-7, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-20035832

RESUMO

Exposure to stress during critical periods of an organism's maturation can result in permanent behavioral changes and induced hyper-responsive to aversive stimuli as adult. Hippocampus is a plastic and vulnerable brain structure that is susceptible to damage during aging and repeated stress. The present study examines the effect of maternal restraint stress on the level of GAP-43, pGAP-43 and synaptophysin in the hippocampus of rat pups. Prenatal stress (PS) causes a significant increase of GAP-43 and pGAP-43 (p

Assuntos
Proteína GAP-43/metabolismo , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/metabolismo , Sinaptofisina/metabolismo , Animais , Corticosterona/metabolismo , Feminino , Masculino , Fosforilação , Gravidez , Terminações Pré-Sinápticas/metabolismo , Distribuição Aleatória , Ratos , Restrição Física
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