Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Neonatology ; 119(6): 727-734, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36252528

RESUMO

INTRODUCTION: Retinopathy of prematurity (ROP) is considered a neurovascular disease. We investigated whether ROP, mild or severe, is associated with neurodevelopmental impairment (NDI) in extremely preterm children. METHODS: We conducted a multicenter retrospective cohort study in southern Taiwan. A total of 394 children <28 weeks of gestation who survived to discharge from 2011 to 2018 received neurodevelopmental assessment at corrected age of 24 months. Severe ROP was defined as ROP of stages 2 plus or worse, or recipients of retinal therapy, and mild ROP as stage 1 or 2 in at least one eye. NDI was defined as cognitive or motor impairment using the Bayley Scales of Infant and Toddler Development, moderate to severe cerebral palsy, or profound hearing loss. RESULTS: Among the 374 children validated for analysis, 157 children (42%) had non-ROP, 145 (39%) mild ROP, and 72 (19%) severe ROP. As ROP severity increased progressively from non-ROP, to mild ROP, and to severe ROP, the rates of NDI increased from 25%, to 46%, and to 61%. The multivariable logistic regression showed that the model included three levels of ROP, and neonatal morbidities achieved better overall performance for NDI than the model that included neonatal morbidities alone. Compared with non-ROP, mild ROP and severe ROP had adjusted odds ratios of 1.90 (95% CI: 1.10-3.28) and 2.75 (95% CI: 1.33-5.67) for NDI, respectively. CONCLUSION: Mild ROP and severe ROP are independent neonatal morbidities associated with NDI. Neurodevelopmental follow-up of extremely preterm children with any stage of ROP is needed.


Assuntos
Encéfalo , Recém-Nascido , Humanos , Pré-Escolar , Estudos Retrospectivos , Taiwan/epidemiologia
2.
Mult Scler Relat Disord ; 66: 104056, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35878513

RESUMO

BACKGROUND: Acute disseminated encephalomyelitis (ADEM) is an immune-mediated encephalopathy with heterogeneous disease courses. However, clinical characteristics for a prognostication of functional recovery from acute episodes of ADEM remain limited. The study aims to characterize the clinical presentations and neuroimaging findings of children with poor functional recoveries from acute episodes of moderate to severe ADEM. METHODS: The multicenter retrospective cohort study included children under 18 years of age who presented with moderate to severe ADEM (modified Rankin Scale [mRS] ≥ 3 at nadir) from 2002 to 2019. Children were assigned to a good recovery group (mRS ≤ 2) and a poor recovery group (mRS ≥ 3) after mean 4.3 months of follow-up. The clinical presentations and the distribution of brain lesions on magnetic resonance imaging were compared between the two groups by the t-test for numerical variables and Fisher's exact test for categorical variables. Analyses of logistic regression were conducted and significant variables in the multivariate model were examined by the receiver operating characteristic curve for the prediction of functional recovery. RESULTS: Among the 73 children with moderate to severe ADEM, 56 (77%) had good functional recoveries and 17 (23%) showed poor functional recoveries. Children with poor recoveries had a lower rate of prodromal headache (12% vs. 39%, p = 0.04), and presented with higher proportions of dystonia (29% vs. 9%, p = 0.046), myoclonus (24% vs. 2%, p = 0.009), and cerebellar lesions on neuroimages (59% vs. 23%, p = 0.01). The multivariate analyses identified that a lack of prodromal headache (OR 0.1, 95% CI 0.005 - 0.7, p = 0.06) and the presentations of myoclonus (OR 21.6, 95% CI 1.7 - 874, p = 0.04) and cerebellar lesions (OR 4.8, 95% CI 1.3 - 19.9, p = 0.02) were associated with poor functional recoveries. These three factors could prognosticate poor outcomes in children with moderate to severe ADEM (area under the receiver operating characteristic curve 0.80, 95% CI 0.68 - 0.93, p = 0.0002). CONCLUSION: Nearly one-fourth of children with moderate to severe ADEM had a poor functional recovery from acute episodes, who were characterized by a lack of prodromal headache, the presentation of myoclonus, and the neuroimaging finding of cerebellar lesions. The clinical variables associated with poor functional recoveries could assist in the planning of immunotherapies during hospitalization for a better outcome in moderate to severe ADEM.


Assuntos
Encefalomielite Aguda Disseminada , Mioclonia , Adolescente , Criança , Encefalomielite Aguda Disseminada/complicações , Encefalomielite Aguda Disseminada/diagnóstico por imagem , Encefalomielite Aguda Disseminada/terapia , Cefaleia/complicações , Humanos , Imageamento por Ressonância Magnética , Mioclonia/complicações , Prognóstico , Estudos Retrospectivos
3.
Front Neurol ; 13: 834252, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359652

RESUMO

Variants in HCN1 are associated with a range of epilepsy syndromes including developmental and epileptic encephalopathies. Here we describe a child harboring a novel de novo HCN1 variant, E246A, in a child with epilepsy and mild developmental delay. By parental report, the child had difficulty in discriminating between colors implicating a visual deficit. This interesting observation may relate to the high expression of HCN1 channels in rod and cone photoreceptors where they play an integral role in shaping the light response. Functional analysis of the HCN1 E246A variant revealed a right shift in the voltage dependence of activation and slowing of the rates of activation and deactivation. The changes in the biophysical properties are consistent with a gain-of-function supporting the role of HCN1 E246A in disease causation. This case suggests that visual function, including color discrimination, should be carefully monitored in patients with diseases due to HCN1 pathogenic variants.

4.
Brain Commun ; 3(2): fcab048, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981995

RESUMO

Hypoxic ischaemia encephalopathy is the major cause of brain injury in new-borns. However, to date, useful biomarkers which may be used to early predict neurodevelopmental impairment for proper commencement of hypothermia therapy is still lacking. This study aimed to determine whether the early neuroimaging characteristics and ultrastructural correlates were associated with different injury progressions and brain damage severity outcomes after neonatal hypoxic ischaemia. Longitudinal 7 T MRI was performed within 6 h, 24 h and 7 days after hypoxic ischaemia in rat pups. The brain damage outcome at 7 days post-hypoxic ischaemia assessed using histopathology and MRI were classified as mild, moderate and severe. We found there was a spectrum of different brain damage severity outcomes after the same duration of hypoxic ischaemia. The severity of brain damage determined using MRI correlated well with that assessed by histopathology. Quantitative MRI characteristics denoting water diffusivity in the tissue showed significant differences in the apparent diffusion coefficient deficit volume and deficit ratios within 6 h, at 24 h and 7 days after hypoxic ischaemia among the 3 different outcome groups. The susceptible brain areas to hypoxic ischaemia were revealed by the temporal changes in regional apparent diffusion coefficient values among three outcome groups. Within 6 h post-hypoxic ischaemia, a larger apparent diffusion coefficient deficit volume and deficit ratios and lower apparent diffusion coefficient values were highly associated with adverse brain damage outcome. In the apparent diffusion coefficient deficit areas detected early after hypoxic ischaemia which were highly associated with severe damage outcome, transmission electron microscopy revealed fragmented nuclei; swollen rough endoplasmic reticulum and degenerating mitochondria in the cortex and prominent myelin loss and axon detraction in the white matter. Taken together, different apparent diffusion coefficient patterns obtained early after hypoxic ischaemia are highly associated with different injury progression leading to different brain damage severity outcomes, suggesting the apparent diffusion coefficient characteristics may be applicable to early identify the high-risk neonates for hypothermia therapy.

5.
Front Mol Neurosci ; 14: 645000, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912011

RESUMO

Hypoxic-ischemia (HI) is a major cause of acquired visual impairment in children from developed countries. Previous studies have shown that systemic administration of 7,8-dihydroxyavone (DHF), a selective tropomyosin receptor kinase B (TrkB) agonist, provides long-term neuroprotection against HI injury in an immature retina. However, the target genes and the mechanisms of the neuroprotective effects of TrkB signaling are not known. In the present study, we induced an HI retinal injury through unilateral common carotid artery ligation followed by 8% oxygen for 2 h in P7 rat pups. DHF was administered intraperitoneally 2 h before and 18 h after the HI injury. A polymerase chain reaction (PCR) array was used to identify the target genes upregulated after the DHF treatment, which was then confirmed with quantitative real-time reverse transcriptase PCR and a western blot. Effects of the downstream mediator of DHF were assessed using an intravitreal injection of neutralizing antibody 4 h after DHF administration (24 h after HI). Meanwhile, the target protein was injected into the vitreous 24 h after HI to validate its protective effect when exogenously supplemented. We found that systemic DHF treatment after HI significantly increased the expression of the artemin (ARTN) gene and protein at P8 and P10, respectively. The neuroprotective effects of DHF were inhibited after the ARTN protein blockade, with an increase in neuroinflammation and astrogliosis. ARTN treatment showed long-term protection against HI injury at both the histopathological and functional levels. The neuroprotective effects of ARTN were related to a decrease in microglial activation at P17 and attenuation of astrogliosis at P29. ARTN enhances phosphorylation of RET, ERK, and JNK, but not AKT or p38 in the immature retina. Altogether, these results suggest that the neuroprotective effect of a TrkB agonist is partially exerted through a mechanism that involves ARTN because the protective effect is ameliorated by ARTN sequestration. ARTN treatment after HI injury protects the immature retina by attenuating late neuroinflammation and astrogliosis in the immature retina relating to the ARTN/RET/JNK/ERK signaling pathway. ARTN may be a strategy by which to provide long-term protection in the immature retina against HI injury.

6.
Neuron ; 106(2): 237-245.e8, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32097630

RESUMO

Lissencephaly (LIS), denoting a "smooth brain," is characterized by the absence of normal cerebral convolutions with abnormalities of cortical thickness. Pathogenic variants in over 20 genes are associated with LIS. The majority of posterior predominant LIS is caused by pathogenic variants in LIS1 (also known as PAFAH1B1), although a significant fraction remains without a known genetic etiology. We now implicate CEP85L as an important cause of posterior predominant LIS, identifying 13 individuals with rare, heterozygous CEP85L variants, including 2 families with autosomal dominant inheritance. We show that CEP85L is a centrosome protein localizing to the pericentriolar material, and knockdown of Cep85l causes a neuronal migration defect in mice. LIS1 also localizes to the centrosome, suggesting that this organelle is key to the mechanism of posterior predominant LIS.


Assuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/genética , Proteínas do Citoesqueleto/genética , Proteínas de Fusão Oncogênica/genética , Adolescente , Adulto , Idade de Início , Animais , Centrossomo/patologia , Criança , Pré-Escolar , Aberrações Cromossômicas , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/diagnóstico por imagem , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/patologia , Feminino , Técnicas de Silenciamento de Genes , Variação Genética , Heterozigoto , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Camundongos , Mutação/genética , Linhagem , Convulsões/etiologia , Adulto Jovem
7.
Invest Ophthalmol Vis Sci ; 59(7): 3124-3135, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30025123

RESUMO

Purpose: Perinatal hypoxic-ischemic (HI) injury causes significant damages in the immature retina. The brain-derived neurotrophic factor is well known for its neuroprotective role but has limited clinical applications. A selective agonist of tyrosine kinase receptor B, 7,8-dihydroxyflavone (DHF), is a powerful therapeutic tool, when administered systemically. However, it remains unclear whether DHF treatment can protect the immature retinas against HI injury. Methods: Postnatal (P) day 7 rat pups were intraperitoneally injected with DHF or vehicle 2 hours before and 18 hours after being subjected to HI injury. The outcomes were assessed at various timepoints after injury by electroretinography and histologic examinations. Neurogenesis was assessed by double-labeling of retinal sections with 5-bromo-2'-deoxyuridine and different neuronal markers. Results: At P8, 24-hours postinjury, brain-derived neurotrophic factor mRNA levels in the retina decreased significantly. DHF treatment partially protected immature retinas at both histologic and functional levels between P14 and P30 but did not prevent apoptosis, inflammation, or damage of the blood-retinal barrier (BRB) at P8. On the other hand, DHF treatment promoted the survival of proliferating inner retinal cells, including Müller glia, and enhanced their transdifferentiation to bipolar cells at P17. Moreover, DHF treatment rescued the levels of extracellular signal-regulated kinase (ERK) phosphorylation, which were significantly decreased after injury. The neuroprotective effects of DHF were markedly eliminated by inhibition of ERK phosphorylation. Conclusions: Early systemic DHF treatment has neuroprotective effects against HI injury in immature retinas, possibly via promoting neurogenesis through the tyrosine kinase receptor B/ERK signaling pathway.Chinese Abstract.


Assuntos
Células Ependimogliais/fisiologia , Flavonas/uso terapêutico , Hipóxia/prevenção & controle , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Doenças Retinianas/prevenção & controle , Animais , Animais Recém-Nascidos , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/genética , Eletrorretinografia , Ativação Enzimática , Hipóxia/enzimologia , Hipóxia/fisiopatologia , Marcação In Situ das Extremidades Cortadas , Fosforilação , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Receptor trkB/agonistas , Regeneração , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/fisiopatologia , Doenças Retinianas/enzimologia , Doenças Retinianas/fisiopatologia
8.
Front Neurol ; 9: 515, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034362

RESUMO

Objective: Focal epilepsy is the most common subtype of epilepsies in which the influence of underlying genetic factors is emerging but remains largely uncharacterized. The purpose of this study is to determine the contribution of currently known disease-causing genes in a large cohort (n = 593) of common focal non-lesional epilepsy patients. Methods: The customized focal epilepsy gene panel (21 genes) was based on multiplex polymerase chain reaction (PCR) and sequenced by Illumina MiSeq platform. Results: Eleven variants (1.85%) were considered as pathogenic or likely pathogenic, including seven novel mutations. There were three SCN1A (p.Leu890Pro, p.Arg1636Ter, and p.Met1714Val), three PRRT2 (two p.Arg217Profs*8 and p.Leu298Pro), two CHRNA4 (p.Ser284Leu, p.Ile321Asn), one DEPDC5 (p.Val516Ter), one PCDH19 (p.Asp233Asn), and one SLC2A1 (p.Ser414Ter) variants. Additionally, 16 other rare variants were classified as unknown significance due to inconsistent phenotype or lack of segregation data. Conclusion: Currently known focal epilepsy genes only explained a very small subset of focal epilepsy patients. This indicates that the underlying genetic architecture of focal epilepsies is very heterogeneous and more novel genes are likely to be discovered. Our study highlights the usefulness, challenges and limitations of using the multi-gene panel as a diagnostic test in routine clinical practice in patients with focal epilepsy.

9.
Mol Neurobiol ; 55(10): 7743-7757, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29460267

RESUMO

Therapy targeting the neurovascular unit may provide effective neuroprotection against neonatal hypoxia-ischemia (HI). We hypothesized that the peripheral injection of hypoxia-preconditioned human umbilical vein endothelial cells (HUVECs) following HI protects against neurovascular damage and provides long-term neuroprotection in a postpartum (P) day-7 rat pup model. Compared with normoxic HUVECs, hypoxic HUVECs showed enhanced migration and angiogenesis in vitro and had augmented migration effects into the brain when administered intraperitoneally in vivo after HI. Moreover, 24 and 72 h post-HI, the hypoxic HUVECs group but not the normoxic HUVECs or culture-medium groups had significantly higher preservation of microvessels and neurons, and attenuation of blood-brain barrier damage than the normal-saline group. Compared to control or normal-saline groups, only the hypoxic HUVECs group had no impaired foot steps and showed a significant reduction of brain area loss at P42. Next-generation sequencing showed hypoxia-induced upregulation and downregulation of 209 and 215 genes in HUVECs, respectively. Upstream regulator analysis by ingenuity pathway analysis (IPA) identified hypoxia-inducible factor 1-alpha as the key predicted activated transcription regulator. After hypoxia, 12 genes (ADAMTS1, EFNA1, HIF1A, LOX, MEOX2, SELE, VEGFA, VEGFC, CX3CL1, HMMR, SDC, and SERPINE) associated with migration and/or angiogenesis were regulated in HUVECs. In addition, 6 genes (VEGFA, VEGFC, NTN4, TGFA, SERPINE1, and CX3CL1) involved in the survival of endothelial and neuronal cells were also markedly altered in hypoxic HUVECs. Thus, cell therapy by using hypoxic HUVECs that enhance migration and neurovascular protection may provide an effective therapeutic strategy for treating neonatal asphyxia.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/patologia , Células Endoteliais da Veia Umbilical Humana/transplante , Hipóxia-Isquemia Encefálica/prevenção & controle , Neuroproteção , Animais , Animais Recém-Nascidos , Apoptose/genética , Comportamento Animal , Hipóxia Celular/genética , Movimento Celular/genética , Sobrevivência Celular/genética , Perfilação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Masculino , Neovascularização Fisiológica/genética , Ratos
10.
Epilepsy Behav ; 56: 95-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26851647

RESUMO

OBJECTIVES: Multiple studies have reported the benefits of vagus nerve stimulation (VNS) on neuropsychological outcomes. The aim of this study was to investigate how VNS affects cognition and psychosocial adjustment in children with refractory epilepsy (RE), and to determine the efficacy of VNS in a Taiwanese population. METHODS: We conducted a one-group pretest-posttest study on pediatric patients with RE. The study comprised 19 males and 18 females, all aged <18 years. We recorded seizure frequency at 3, 12, and 24 months after VNS device implantation. Intelligence quotients (IQ) were assessed using the Wechsler Intelligence Scale for Children - IV. The Parental Stress Index (PSI) scores were evaluated by a pediatric psychologist. RESULTS: Vagus nerve stimulation device implantation significantly reduced seizure frequency at 3, 12 and 24 months, especially in young children (<12 years). No significant improvement in IQ test performance was observed, though there were significant improvements in the PSI, especially in young children. CONCLUSIONS: Vagus nerve stimulation device implantation does not significantly improve cognition function, but it does significantly reduce seizure frequency and stress in parent-child relationships, especially in young children (<12 years). These findings suggest that VNS should be considered as an alternative therapy for patients proven to have seizures that are medically refractory, especially those younger than 12 years of age.


Assuntos
Epilepsia Resistente a Medicamentos/psicologia , Epilepsia Resistente a Medicamentos/terapia , Testes Neuropsicológicos , Relações Pais-Filho , Estimulação do Nervo Vago/tendências , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Testes de Inteligência , Estudos Longitudinais , Masculino , Estudos Prospectivos , Psicologia da Criança/tendências , Taiwan/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Estimulação do Nervo Vago/métodos , Escalas de Wechsler
11.
Invest Ophthalmol Vis Sci ; 56(8): 4300-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26176867

RESUMO

PURPOSE: Visual loss associated with hypoxic-ischemic (HI) brain damage is the most common cause of visual impairment in children of developed countries. A neuroprotective role for Wnt/ß-catenin signaling has been demonstrated in several neurodegenerative disorders. The association of Wnt signaling with HI injury in immature retina has not been established. METHODS: On postnatal day 7 (P7), HI was induced by unilateral common carotid artery ligation followed by 8% oxygen hypoxia for 2 hours. The pups received intravitreous injection (i.v.i) of PBS, Dickkopf-1 (DKK-1, the negative modulator of Wnt/ß-catenin pathway) antisense (AS) or sense (S) oligonucleotides at various concentrations for pretreatment (24 and 1 hour before HI) or post treatment (1 and 4 hours after HI). For chronic treatments, animals received repeated intraperitoneal (i.p.) injection of DKK-1-AS, DKK-1-S, lithium chloride (LiCl), or vehicles after HI. The retinal injury was assessed by electroretinography (ERG, P21, and P30) and immunohistochemical staining (P8 or P30). RESULTS: Pretreatment with DKK-1-AS (i.v.i.) attenuated DKK-1 and enhanced ß-catenin expression, but did not protect immature retina against HI injury at both pathological and functional levels. Post treatment with DKK-1-AS (i.v.i. or i.p.) also did not rescue HI retinopathy. Chronic systemic LiCl treatment did not decrease Müller cell activation or neuronal damage in HI retinal injury. CONCLUSIONS: Our data demonstrated that DKK-1 inhibition or chronic lithium treatment did not protect the immature retina from HI injury. It is speculated that the enhanced canonical Wnt/ß-catenin signaling is not sufficient to protect the immature retina from HI injury.


Assuntos
Hipóxia/metabolismo , Retina/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Morte Celular , Modelos Animais de Doenças , Eletrorretinografia , Feminino , Hipóxia/patologia , Hipóxia/fisiopatologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Retina/patologia , Transdução de Sinais
12.
J Neuroinflammation ; 11: 215, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25540015

RESUMO

BACKGROUND: Hypoxic-ischemia (HI) and inflammation are the two major pathogenic mechanisms of brain injury in very preterm infants. The neurovascular unit is the major target of HI injury in the immature brain. Systemic inflammation may worsen HI by up-regulating neuroinflammation and disrupting the blood-brain barrier (BBB). Since neurons and oligodendrocytes, microvascular endothelial cells, and microglia may closely interact with each other, there may be a common signaling pathway leading to neuroinflammation and neurovascular damage after injury in the immature brain. TNF-α is a key pro-inflammatory cytokine that acts through the TNF receptor (TNFR), and c-Jun N-terminal kinases (JNK) are important stress-responsive kinases. OBJECTIVE: To determine if TNFR1-JNK signaling is a shared pathway underlying neuroinflammation and neurovascular injury after lipopolysaccharide (LPS)-sensitized HI in the immature brain. METHODS: Postpartum (P) day-5 mice received LPS or normal saline (NS) injection before HI. Immunohistochemistry, immunoblotting and TNFR1- and TNFR2-knockout mouse pups were used to determine neuroinflammation, BBB damage, TNF-α expression, JNK activation, and cell apoptosis. The cellular distribution of p-JNK, TNFR1/TNFR2 and cleaved caspase-3 were examined using immunofluorescent staining. RESULTS: The LPS + HI group had significantly greater up-regulation of activated microglia, TNF-α and TNFR1 expression, and increases of BBB disruption and cleaved caspase-3 levels at 24 hours post-insult, and showed more cortical and white matter injury on P17 than the control and NS + HI groups. Cleaved caspase-3 was highly expressed in microvascular endothelial cells, neurons, and oligodendroglial precursor cells. LPS-sensitized HI also induced JNK activation and up-regulation of TNFR1 but not TNFR2 expression in the microglia, endothelial cells, neurons, and oligodendrocyte progenitors, and most of the TNFR1-positive cells co-expressed p-JNK. Etanercept (a TNF-α inhibitor) and AS601245 (a JNK inhibitor) protected against LPS-sensitized HI brain injury. The TNFR1-knockout but not TNFR2-knockout pups had significant reduction in JNK activation, attenuation of microglial activation, BBB breakdown and cleaved caspase-3 expression, and showed markedly less cortical and white matter injury than the wild-type pups after LPS-sensitized HI. CONCLUSION: TNFR1-JNK signaling is the shared pathway leading to neuroinflammation and neurovascular damage after LPS-sensitized HI in the immature brain.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/fisiologia , Receptores Tipo I de Fatores de Necrose Tumoral/biossíntese , Animais , Animais Recém-Nascidos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Feminino , Hipóxia-Isquemia Encefálica/induzido quimicamente , Hipóxia-Isquemia Encefálica/patologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout
13.
BMC Neurol ; 14: 216, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25421405

RESUMO

BACKGROUND: Hereditary spastic paraplegias (HSPs) are a group of neurodegenerative diseases characterized by progressive spasticity and weakness of the lower limbs. SPG4, SPG3A and SPG31 are the three leading causes of autosomal dominant (AD) HSPs. METHODS: A total of 20 unrelated AD-HSP families were recruited for clinical and genetic assessment. Detection of mutations in SPG4, SPG3A and SPG31 genes was conducted according to a standard protocol. Genotype-phenotype correlations and determinants for disease severity and progression were analyzed. RESULTS: Mutations in the SPG4 gene (SPAST) were detected in 18 (90%) of the AD-HSP families. Mutations in SPG4, SPG3A and SPG31 genes were not detected in the remaining two families. Considerable variations in clinical features were noted, even for mutation carriers from the same family. Mutations causing complete loss of the spastin AAA cassette were associated with earlier onset of disease (20 ± 18 years) compared with those with preservation of partial or total AAA cassette (32 ± 19 years, p = 0.041). For those with SPG4 mutations, disease severity was related to the patients' current age, and the progression rate of disease was positively correlated with age at onset. CONCLUSIONS: SPG4 accounts for most of the AD-HSP cases in Taiwanese, with a frequency significantly higher than in other populations. SPAST mutations which predict complete loss of the spastin AAA cassette were associated with an earlier onset of disease.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Ligação ao GTP/genética , Proteínas de Membrana/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Adulto , Idade de Início , Idoso , Povo Asiático/genética , Criança , Pré-Escolar , Progressão da Doença , Feminino , Genes Dominantes , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Espastina , Adulto Jovem
14.
J Cereb Blood Flow Metab ; 34(4): 668-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24398931

RESUMO

Microvascular injury early after hypoxic ischemia (HI) may contribute to neonatal brain damage. N-methyl-D-aspartate receptor overstimulation activates neuronal nitric oxide synthases (nNOS). We hypothesized that microvascular damage occurs early post-HI via nNOS activation and contributes to brain injury. Postpartum day-7 rat pups were treated with 7-nitroindazole (7-NI) or aminoguanidine (AG) before or after HI. Electron microscopy was performed to measure neuronal and endothelial cell damage. There were vascular lumen narrowing at 1 hour, pyknotic neurons at 3 hours, and extensive neuronal damage and loss of vessels at 24 hours post HI. Early after reoxygenation, there were neurons with heterochromatic chromatin and endothelial cells with enlarged nuclei occluding the lumen. There was also increased 3-nitrotyrosin in the microvessels and decreased cerebral blood perfusion. 7-NI and AG treatment before hypoxia provided complete and partial neuroprotection, respectively. Early post-reoxygenation, the AG group showed significantly increased microvascular nitrosative stress, microvascular interruptions, swollen nuclei that narrowed the vascular lumen, and decreased cerebral perfusion. The 7-NI group showed significantly decreased microvascular nitrosative stress, patent vascular lumen, and increased cerebral perfusion. Our results indicate that microvascular damage occurs early and progressively post HI. Neuronal nitric oxide synthases activation contributes to microvascular damage and decreased cerebral perfusion early after reoxygenation and worsens brain damage.


Assuntos
Circulação Cerebrovascular/fisiologia , Hipóxia-Isquemia Encefálica/patologia , Microvasos/ultraestrutura , Óxido Nítrico Sintase Tipo I/metabolismo , Animais , Animais Recém-Nascidos , Células Endoteliais/enzimologia , Células Endoteliais/ultraestrutura , Endotélio Vascular/enzimologia , Endotélio Vascular/ultraestrutura , Ativação Enzimática , Hipóxia-Isquemia Encefálica/enzimologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Masculino , Microscopia Eletrônica de Transmissão , Microvasos/enzimologia , Neurônios/enzimologia , Neurônios/ultraestrutura , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Oxigênio/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Brain Dev ; 36(3): 248-53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23694758

RESUMO

AIM: Paraneoplastic neurological diseases (PND) are rare, but potentially treatable disorders. Paraneoplastic encephalitis is rapidly emerging as an important but likely under-recognized condition in children. The aim of this study was to assess the prevalence and spectrum of PND in children with benign ovary tumor and the long-term outcome. PATIENTS AND METHODS: We retrospectively reviewed the charts of all female patients below 18years of age diagnosed with a benign ovarian tumor proven by pathology between January 1993 and December 2010. All the clinical symptoms developed within 5years of tumor diagnosis and the related investigations were recorded. RESULTS: There were total 133 children and adolescents with benign ovarian tumors, mostly mature teratoma. Six patients (4.5%) had neuropsychiatric manifestations and all but one were beyond age 10years. The most common neuropsychiatric presentations were depression or low mood (84%), headache (50%), mutism (50%), hypoventilation (50%), seizures (30%), hallucination (30%), vomiting and hypersalivation (30%). Three patients (2.2%) had serious PND including acute disseminated encephalomyelitis in 1 and anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis in 2. Although all of three improved after tumor removal, one without immunotherapy had neurological sequelae and prolonged ICU stay. CONCLUSION: The prevalence of PND in benign ovary tumor is not so uncommon in children. It is important to survey ovary tumors in female adolescents with subacute presentation of multiple-level involvement of neuraxis where no clear alternate diagnosis is possible. Treatment of serious PND associated with ovary tumors should include immunotherapy in addition to tumor removal.


Assuntos
Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico , Síndromes Paraneoplásicas do Sistema Nervoso/epidemiologia , Adolescente , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Imageamento por Ressonância Magnética , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Síndromes Paraneoplásicas do Sistema Nervoso/patologia , Síndromes Paraneoplásicas do Sistema Nervoso/terapia , Prevalência , Prognóstico , Estudos Retrospectivos , Medula Espinal/patologia , Teratoma/diagnóstico , Teratoma/epidemiologia , Teratoma/patologia , Teratoma/terapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
Stroke ; 44(8): 2275-83, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23715956

RESUMO

BACKGROUND AND PURPOSE: Low level of thyroid hormone is a strong independent risk factor for white matter (WM) injury, a major cause of cerebral palsy, in preterm infants. Thyroxin upregulates brain-derived neurotrophic factor during development. We hypothesized that thyroxin protected against preoligodendrocyte apoptosis and WM injury in the immature brain via upregulation of brain-derived neurotrophic factor. METHODS: Postpartum (P) day-7 male rat pups were exposed to hypoxic ischemia (HI) and intraperitoneally injected with thyroxin (T4; 0.2 mg/kg or 1 mg/kg) or normal saline immediately after HI at P9 and P11. WM damage was analyzed for myelin formation, axonal injury, astrogliosis, and preoligodendrocyte apoptosis. Neurotrophic factor expression was assessed by real-time polymerase chain reaction and immunohistochemistry. Neuromotor functions were measured using open-field locomotion (P11 and P21), inclined plane climbing (P11), and beam walking (P21). Intracerebroventricular injection of TrkB-Fc or systemic administration of 7,8-dihydroxyflavone was performed. RESULTS: On P11, the HI group had significantly lower blood T4 levels than the controls. The HI group showed ventriculomegaly and marked reduction of myelin basic protein immunoreactivities in the WM. T4 (1 mg/kg) treatment after HI markedly attenuated axonal injury, astrocytosis, and microgliosis, and increased preoligodendrocyte survival. In addition, T4 treatment significantly increased myelination and selectively upregulated brain-derived neurotrophic factor expression in the WM, and improved neuromotor deficits after HI. The protective effect of T4 on WM myelination and neuromotor performance after HI was significantly attenuated by TrkB-Fc. Systemic 7,8-dihydroxyflavone treatment ameliorated hypomyelination after HI injury. CONCLUSIONS: T4 protects against WM injury at both pathological and functional levels via upregulation of brain-derived neurotrophic factor-TrkB signaling in the immature brain.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Hipóxia-Isquemia Encefálica/terapia , Leucoencefalopatias/terapia , Receptor trkB/fisiologia , Tiroxina/administração & dosagem , Animais , Animais Recém-Nascidos , Comportamento Animal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Modelos Animais de Doenças , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/patologia , Injeções Intraperitoneais , Injeções Intraventriculares , Leucoencefalopatias/etiologia , Leucoencefalopatias/patologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Distribuição Aleatória , Ratos , Receptor trkB/administração & dosagem , Receptor trkB/biossíntese , Tiroxina/fisiologia , Regulação para Cima/fisiologia
17.
Stroke ; 44(5): 1402-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23449265

RESUMO

BACKGROUND AND PURPOSE: Agents that protect against neurovascular damage provide a powerful neuroprotective strategy. Human umbilical vein endothelial cells (HUVECs) may be used to treat neonates with hypoxic-ischemia (HI) because of its autologous capability. We hypothesized that peripherally injected HUVECs entered the brain after HI, protected against neurovascular damage, and provided protection via stromal cell-derived factor 1/C-X-C chemokine receptor type 4 pathway in neonatal brain. METHODS: Postpartum day 7 rat pups received intraperitoneal injections of low-passage HUVEC-P4, high-passage HUVEC-P8, or conditioned medium before and immediately after HI. HUVECs were transfected with adenovirus-green fluorescent protein for cell tracing. Oxygen-glucose deprivation was established by coculturing HUVEC-P4 with mouse neuroblastoma neuronal cells (Neuro-2a) and with mouse immortalized cerebral vascular endothelial cells (b.End3). RESULTS: HUVEC-P4-treated group had more blood levels of green fluorescent protein-positive cells than HUVEC-P8-treated group 3 hours postinjection. Intraperitoneally injected HUVEC-P4, but not HUVEC-P8, entered the cortex after HI and positioned closed to the neurons and microvessels. Compared with the condition medium-treated group, the HUVEC-P4-treated but not the HUVEC-P8-treated group showed significantly less neuronal apoptosis and blood-brain barrier damage and more preservation of microvessels in the cortex 24 hours after HI. On postpartum day 14, the HUVEC-P4-treated group showed significant neuroprotection compared with the condition medium-treated group. Stromal cell-derived factor 1 was upregulated in the ipsilateral cortex 3 hours after HI, and inhibiting the stromal cell-derived factor 1/C-X-C chemokine receptor type 4 reduced the protective effect of HUVEC-P4. In vitro transwell coculturing of HUVEC-P4 also significantly protected against oxygen-glucose deprivation cell death in neurons and endothelial cells. CONCLUSIONS: Cell therapy using HUVECs may provide a powerful therapeutic strategy in treating neonates with HI.


Assuntos
Encéfalo/metabolismo , Quimiocina CXCL12/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Receptores CXCR4/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Movimento Celular , Técnicas de Cocultura , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Masculino , Camundongos , Neurônios/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley
18.
Stroke ; 44(1): 162-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23192759

RESUMO

BACKGROUND AND PURPOSE: The neurovascular unit is a major target of hypoxia-ischemia (HI) injury in the neonatal brain. Although neurons are the cellular target of ischemic preconditioning (IP), vessel tolerance also contributes greatly to protection. Nerves and vessels cross-talk and use common signals during development. Cellular inhibitor of apoptosis 1 (cIAP1) is an important regulator that inhibits apoptosis. This study hypothesized that cIAP1 is a shared molecule underlying IP-mediated neurovascular protection against HI in the neonatal brain. METHODS: In vivo IP was induced by 2-hour reversible occlusion of right carotid artery 24 hours before HI on postpartum day 7 in rat pups. In vitro oxygen-glucose deprivation (OGD) preconditioning was established in SH-SY5Y neuronal cells and in human microvascular endothelial cell-1 vascular endothelial cells. cIAP1 expression was inhibited by cIAP1 small interfering RNA in vivo or by lentivirus-mediated short hairpin RNA in vitro, or was upregulated by the lentiviral expression system. RESULTS: IP reduced apoptosis, selectively increased cIAP1 in neurons and vascular endothelial cells, and provided long-term neuroprotection against HI. Intracerebroventricular delivery of cIAP1 small interfering RNA significantly attenuated IP-mediated cIAP1 upregulation and neuroprotection in vivo. In vitro, OGD preconditioning induced cIAP1 and protected against OGD cell death in SH-SY5Y neuronal and human microvascular endothelial cells-1. Knockdown of cIAP1 by lentivirus-mediated short hairpin RNA decreased the protective effect of OGD preconditioning in SH-SY5Y and human microvascular endothelial cell-1, whereas overexpression of cIAP1 by lentivirus protected against OGD in these cells. CONCLUSIONS: cIAP1 is a shared molecule underlying IP-induced protection in neurons and vascular endothelial cells against HI in the neonatal brain.


Assuntos
Encéfalo/metabolismo , Endotélio Vascular/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Proteínas Inibidoras de Apoptose/biossíntese , Precondicionamento Isquêmico/métodos , Neurônios/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Linhagem Celular Tumoral , Endotélio Vascular/patologia , Humanos , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/prevenção & controle , Masculino , Neurônios/patologia , Ratos , Ratos Sprague-Dawley
19.
Pediatr Res ; 72(3): 224-31, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22669292

RESUMO

BACKGROUND: Visual loss associated with brain damage, especially hypoxic-ischemic (HI) encephalopathy, is the most common cause of visual impairment in children in developed countries. We hypothesized that HI insults can cause long-term damage in immature eyes. METHODS: In postnatal day 7 rat pups, HI was induced by unilateral common carotid artery ligation followed by hypoxia. Retina damage was assessed by electroretinography (ERG) and cell counting. Neuronal injury and astrogliosis were evaluated by terminal deoxynucleotidyl transferase nick-end labeling, cleaved caspase 3, ED1, and glial fibrillary acidic protein immunostaining. RESULTS: We observed rapid and persistently extensive injuries in the ganglia cell layer (GCL), inner plexiform layer, and inner nuclear layer (INL) in ipsilateral retinas after HI injury, corresponding to the marked alteration in ERG. HI insult caused prominent microglial and Muller cell activation in ipsilateral inner retinas. Neuronal death in the GCL and INL after HI injury was mainly apoptotic, involving caspase-dependent pathways. CONCLUSION: Our study demonstrated the first evidence of HI retinal damage at both the pathological and functional level using the Vannucci model in neonatal rats. Because retinal damage is often associated with HI injury, it is important to demonstrate that a particular neuroprotective strategy effectively preserves the retina in addition to the brain.


Assuntos
Hipóxia/complicações , Isquemia/complicações , Retina/lesões , Animais , Apoptose , Morte Celular , Eletrorretinografia , Neurônios/patologia , Ratos , Retina/patologia
20.
Eur J Ophthalmol ; 22(6): 980-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22388777

RESUMO

PURPOSE: To investigate the correlation between periventricular leukomalacia (PVL) and retinopathy of prematurity (ROP), which are complications of perinatal and postnatal hypoxic-ischemic insults in premature infants. METHODS: In this retrospective case series study, from 1996 to 2008, after excluding cases with follow-up of less than 3 months, we reviewed medical charts of babies who had gestational age (GA) less than 30 weeks or birthweight (BW) less than 2000 g. A total of 195 patients were diagnosed with ROP and/or PVL and were enrolled in this analysis. We investigated the correlation between ROP and PVL with Pearson chi-square test and evaluated BW, GA, and Apgar scores at 1 minute and 5 minutes after birth as risk factors by independent t test. RESULTS: There were no significant differences in the prevalence of PVL between patients who received ROP treatment and those who did not receive ROP treatment. The BW was significantly lower in patients with PVL than in patients without PVL. Gestational age, BW, and Apgar scores significantly differed between patients who did and did not receive retinal treatment for ROP. CONCLUSIONS: Periventricular leukomalacia did not increase the severity of ROP or requirement of ROP treatment. Birthweight, GA, and Apgar scores were the principal factors that determined the necessity of ROP treatment.


Assuntos
Leucomalácia Periventricular/fisiopatologia , Retinopatia da Prematuridade/fisiopatologia , Índice de Apgar , Peso ao Nascer , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Leucomalácia Periventricular/diagnóstico , Leucomalácia Periventricular/terapia , Masculino , Prevalência , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/terapia , Estudos Retrospectivos , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...