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1.
Clin Neurophysiol ; 166: 108-116, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39153459

RESUMO

OBJECTIVE: The study aimed to address the challenge of early assessment of neonatal hypoxic-ischemic encephalopathy (HIE) severity to identify candidates for therapeutic hypothermia (TH). The objective was to develop an automated classification model for neonatal EEGs, enabling accurate HIE severity assessment 24/7. METHODS: EEGs recorded within 6 h of life after perinatal anoxia were visually graded into 3 severity groups (HIE French Classification) and quantified using 6 qEEG markers measuring amplitude, continuity and frequency content. Machine learning models were developed on a dataset of 90 EEGs and validated on an independent dataset of 60 EEGs. RESULTS: The selected model achieved an overall accuracy of 80.6% in the development phase and 80% in the validation phase. Notably, the model accurately identified 28 out of 30 children for whom TH was indicated after visual EEG analysis, with only 2 cases (moderate EEG abnormalities) not recommended for cooling. CONCLUSIONS: The combination of clinically relevant qEEG markers led to the development of an effective automated EEG classification model, particularly suited for the post-anoxic latency phase. This model successfully discriminated neonates requiring TH. SIGNIFICANCE: The proposed model has potential as a bedside clinical decision support tool for TH.


Assuntos
Eletroencefalografia , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Humanos , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/fisiopatologia , Hipóxia-Isquemia Encefálica/classificação , Hipóxia-Isquemia Encefálica/diagnóstico , Hipotermia Induzida/métodos , Recém-Nascido , Eletroencefalografia/métodos , Feminino , Masculino , Aprendizado de Máquina
2.
Brain Res ; 1809: 148369, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37061081

RESUMO

Estetrol (E4) is a natural estrogen synthesized only during pregnancy. It has strong neuroprotective and antioxidative activities. The aim of the present study was to define the neuroprotective potency of E4 encapsulated either in liposome (Lipo-E4) or in drug-in cyclodextrin (HP-ß-CD) in liposome (DCL) system, and compare them with a single use of E4. In vitro studies were performed in an oxidative stress model of primary hippocampal neuronal cell cultures, followed by the lactate dehydrogenase activity and cell proliferation assays. In vivo studies were conducted by using a model of neonatal hypoxic-ischemic encephalopathy in immature rat pups. Brain samples were studied by (immuno)histochemistry for the detection of survived cells, expression of microtubule-associated protein-2, myelin basic protein, doublecortin and vascular-endothelial growth factor. Concentrations of glial fibrillary acidic protein in blood serum were studied by ELISA. In vitro, cell proliferation was significantly up-regulated in cultures treated either by DCL-E4 or E4 compared to the control cells, whereas DCL-E4 treated cells had significantly higher survival rate than the cells treated by E4 alone. Evaluation of brain samples showed that DCL-E4 and a high dose of E4 alone significantly preserve the grey and the white matter loses, and diminish GFAP expression in blood. Although DCL-E4 and E4 have similar effect on neurogenesis in the hippocampus and the cortex, DCL-E4 treatment significantly up-regulates angiogenesis in the hippocampus compared to a single use of E4. Present work reveals for the first time that liposome-encapsulated E4 might be a better alternative to a single use of E4.


Assuntos
Estetrol , Hipóxia-Isquemia Encefálica , Ratos , Animais , Estetrol/metabolismo , Estetrol/farmacologia , Estetrol/uso terapêutico , Lipossomos/metabolismo , Lipossomos/farmacologia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Estrogênios/metabolismo , Neurônios/metabolismo
3.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35805891

RESUMO

Nicotine exposure either from maternal cigarette smoking or e-cigarette vaping is one of the most common risk factors for neurodevelopmental disease in offspring. Previous studies revealed that perinatal nicotine exposure programs a sensitive phenotype to neonatal hypoxic-ischemic encephalopathy (HIE) in postnatal life, yet the underlying mechanisms remain undetermined. The goal of the present study was to determine the regulatory role of H19/miR-181a/ATG5 signaling in perinatal nicotine exposure-induced development of neonatal brain hypoxic-ischemic sensitive phenotype. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. All experiments were conducted in offspring pups at postnatal day 9 (P9). Perinatal nicotine exposure significantly enhanced expression of miR-181a but attenuated autophagy-related protein 5 (ATG5) mRNA and protein levels in neonatal brains. Of interest, miR-181a mimicking administration in the absence of nicotine exposure also produced dose-dependent increased hypoxia/ischemia (H/I)-induced brain injury associated with a decreased ATG5 expression, closely resembling perinatal nicotine exposure-mediated effects. Locked nucleic acid (LNA)-miR-181a antisense reversed perinatal nicotine-mediated increase in H/I-induced brain injury and normalized aberrant ATG5 expression. In addition, nicotine exposure attenuated a long non-coding RNA (lncRNA) H19 expression level. Knockdown of H19 via siRNA increased the miR-181a level and enhanced H/I-induced neonatal brain injury. In conclusion, the present findings provide a novel mechanism that aberrant alteration of the H19/miR-181a/AGT5 axis plays a vital role in perinatal nicotine exposure-mediated ischemia-sensitive phenotype in offspring and suggests promising molecular targets for intervention and rescuing nicotine-induced adverse programming effects in offspring.


Assuntos
Lesões Encefálicas , Sistemas Eletrônicos de Liberação de Nicotina , Hipóxia-Isquemia Encefálica , MicroRNAs , RNA Longo não Codificante , Animais , Animais Recém-Nascidos , Proteína 5 Relacionada à Autofagia/metabolismo , Encéfalo/metabolismo , Feminino , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Isquemia , MicroRNAs/genética , MicroRNAs/metabolismo , Nicotina/toxicidade , Fenótipo , Gravidez , RNA Longo não Codificante/genética , Ratos
4.
Antioxidants (Basel) ; 10(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34572976

RESUMO

N-acetylcysteine (NAC) and vitamin D provide effective neuroprotection in animal models of severe or inflammation-sensitized hypoxic ischemic encephalopathy (HIE). To translate these FDA-approved drugs to HIE neonates, we conducted an early phase, open-label trial of 10 days of NAC (25, 40 mg/kg q12h) + 1,25(OH)2D (calcitriol 0.05 mg/kg q12h, 0.03 mg/kg q24h), (NVD), for pharmacokinetic (PK) estimates during therapeutic hypothermia and normothermia. We paired PK samples with pharmacodynamic (PD) targets of plasma isoprostanoids, CNS glutathione (GSH) and total creatine (tCr) by serial MRS in basal ganglia (BG) before and after NVD infusion at five days. Infants had moderate (n = 14) or severe HIE (n = 16), funisitis (32%), and vitamin D deficiency (75%). NVD resulted in rapid, dose-responsive increases in CNS GSH and tCr that correlated positively with plasma [NAC], inversely with plasma isofurans, and was greater in infants with lower baseline [GSH] and [tCr], suggesting increases in these PD markers were titrated by neural demand. Hypothermia and normothermia altered NAC PK estimates. NVD was well tolerated. Excluding genetic syndromes (2), prolonged ECMO (2), lost-to-follow-up (1) and SIDS death (1), 24 NVD treated HIE infants have no evidence of cerebral palsy, autism or cognitive delay at 24-48 months. These data confirm that low, safe doses of NVD in HIE neonates decreased oxidative stress in plasma and CNS, improved CNS energetics, and are associated with favorable developmental outcomes at two to four years.

5.
Brain Res Bull ; 174: 131-140, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34058286

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE), is a major cause of neurologic disorders in terms of neonates, with the unclear underlying mechanisms. In the study, triphenyl tetrazolium chloride (TTC) staining and Zea-longa score were performed to examine the neurologic damage in hypoxia and ischemia (HI) rats. The results showed that HI induced obviously infarct and serious neurologic impairment in neonatal rats. Then, protein chip was applied to detect the differential expression genes in cortex and hippocampus and found the brain-derived neurotrophic factor (BDNF) down-regulated both in cortex and hippocampus. Moreover, low expression of BDNF after HI in right cortex and hippocampus was validate by immunohistochemistry (IHC) and Western Blotting (WB). Afterwards, overexpressing and interfering HSV vector were produced, then verified by immunofluorescent staining and real-time quantitative polymerase chain reaction (qRT-PCR). The results of Tuj1 staining indicated that overexpression of BDNF could promote axonal regeneration and inhibit neuron swelling, whereas BDNF interference take an opposite effect after Oxygen glucose deprivation (OGD) injury. Finally, the interaction network among BDNF and associated proteins as examined by Genemania and confirmed by qRT-PCR. We found that the expression of VDAC1 was decreased and Stx1b was increased when BDNF overexpressing, which indicated that BDNF promoted neurite regrowth after OGD might be related to downregulation of VDAC1 and upregulation of Stx1b. Our results might provide novel strategy for the treatment of neurological defects induced by cerebral ischemia and hypoxia.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Sobrevivência Celular/efeitos dos fármacos , Terapia Genética/métodos , Hipóxia-Isquemia Encefálica/terapia , Neurônios/efeitos dos fármacos , Sintaxina 1/biossíntese , Canal de Ânion 1 Dependente de Voltagem/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Axônios/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Feminino , Glucose/deficiência , Regeneração Nervosa/efeitos dos fármacos , Neuritos , Gravidez , Ratos , Ratos Sprague-Dawley
6.
Am J Physiol Regul Integr Comp Physiol ; 317(6): R803-R813, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31553625

RESUMO

Maternal cigarette smoking is a major perinatal insult that contributes to an increased risk of cardiovascular and neurodevelopmental diseases in offspring. Our previous studies revealed that perinatal nicotine exposure reprograms a sensitive phenotype in neonatal hypoxic-ischemic encephalopathy (HIE), yet the underlying molecular mechanisms remain largely elusive. The present study tested the hypothesis that perinatal nicotine exposure impacts autophagy signaling in the developing brain, resulting in enhanced susceptibility to neonatal HIE. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. Neonatal HIE was conducted in 9-day-old male rat pups. Protein kinase B/glycogen synthase kinase-3ß/mammalian target of rapamycin (Akt/GSK-3ß/mTOR) signaling and key autophagy markers were determined by Western blotting analysis. Rapamycin and MK2206 were administered via intracerebroventricular injection. Nicotine exposure significantly inhibited autophagy activities in neonatal brain tissues, characterized by an increased ratio of phosphoylated (p-) to total mTOR protein expression but reduced levels of autophagy-related 5, Beclin 1, and LC3ßI/II. Treatment with mTOR inhibitor rapamycin effectively blocked nicotine-mediated autophagy deficiency and, more importantly, reversed the nicotine-induced increase in HI brain infarction. In addition, nicotine exposure significantly upregulated p-Akt and p-GSK-3ß. Treatment with the Akt selective inhibitor MK2206 reversed the enhanced p-Akt and p-GSK-3ß, restored basal autophagic flux, and abolished nicotine-mediated HI brain injury. These findings suggest that perinatal nicotine-mediated alteration of Akt/GSK-3ß/mTOR signaling plays a key role in downregulation of autophagic flux, which contributes to the development of hypoxia/ischemia-sensitive phenotype in the neonatal brain.


Assuntos
Autofagia/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipóxia-Isquemia Encefálica/induzido quimicamente , Nicotina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/genética , Injeções Intraventriculares , Agonistas Nicotínicos/farmacologia , Gravidez , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/genética
7.
Early Hum Dev ; 122: 8-14, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29803998

RESUMO

BACKGROUND: Neonates with hypoxic-ischemic encephalopathy (HIE) and seizures have poorer outcome for undetermined reasons. AIMS: Our aim was to determine if brain imaging was more abnormal in neonates with HIE and electrographically confirmed seizures and whether this was impacted by seizure burden. STUDY DESIGN: Single center retrospective review. SUBJECTS: Forty-eight term neonates with HIE (with and without seizures) underwent MRI brain scans before age 14 days between the years 2008 and 2013. OUTCOME MEASURES: Images were rated using a MRI injury score and fractional anisotropy (FA) values were extracted from diffusion tensor imaging (DTI). RESULTS: The seizure group (n = 25) had significantly more injury within white matter, basal ganglia, posterior limb of internal capsule, and watershed areas compared to the group without seizures (n = 23). The severity of injury in all measured areas increased with increasing seizure severity. The seizure group also had lower FA values in posterior limb of the internal capsule and the splenium of corpus callosum. CONCLUSIONS: Neonates with HIE and seizures had more brain injury that occurred in areas typically affected by HIE and was greater with higher seizure burden. Seizures may be a marker of more severe brain injury or seizures themselves may amplify brain damage from HIE.


Assuntos
Imagem de Tensor de Difusão , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Doenças do Recém-Nascido/diagnóstico por imagem , Imageamento por Ressonância Magnética , Convulsões/diagnóstico por imagem , Feminino , Humanos , Hipóxia-Isquemia Encefálica/complicações , Recém-Nascido , Masculino , Convulsões/complicações
8.
Clin Neurophysiol ; 127(1): 297-309, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26093932

RESUMO

OBJECTIVE: This work presents a novel automated system to classify the severity of hypoxic-ischemic encephalopathy (HIE) in neonates using EEG. METHODS: A cross disciplinary method is applied that uses the sequences of short-term features of EEG to grade an hour long recording. Novel post-processing techniques are proposed based on majority voting and probabilistic methods. The proposed system is validated with one-hour-long EEG recordings from 54 full term neonates. RESULTS: An overall accuracy of 87% is achieved. The developed grading system has improved both the accuracy and the confidence/quality of the produced decision. With a new label 'unknown' assigned to the recordings with lower confidence levels an accuracy of 96% is attained. CONCLUSION: The statistical long-term model based features extracted from the sequences of short-term features has improved the overall accuracy of grading the HIE injury in neonatal EEG. SIGNIFICANCE: The proposed automated HIE grading system can provide significant assistance to healthcare professionals in assessing the severity of HIE. This represents a practical and user friendly implementation which acts as a decision support system in the clinical environment. Its integration with other EEG analysis algorithms may improve neonatal neurocritical care.


Assuntos
Eletroencefalografia/classificação , Hipóxia-Isquemia Encefálica/classificação , Hipóxia-Isquemia Encefálica/diagnóstico , Máquina de Vetores de Suporte/classificação , Eletroencefalografia/métodos , Feminino , Humanos , Hipóxia-Isquemia Encefálica/fisiopatologia , Recém-Nascido , Masculino
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