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1.
World Neurosurg ; 133: e31-e61, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31415895

RESUMO

BACKGROUND: The association between matrix metalloproteinase 9 (MMP-9) gene -1562C/T (rs3918242) polymorphism and the susceptibility of ischemic stroke (IS) has been investigated. However, results were ambiguous and inconsistent. Therefore, we performed this study to better assess the potential relationship between rs3918242 polymorphism and susceptibility risk of IS. METHODS: We included case-control studies concerning the relationship between the rs3918242 polymorphism and IS, and odds ratios with corresponding 95% confidence intervals were used to describe the associations. Furthermore, meta-regression analyses, heterogeneity, cumulative analyses, sensitivity analyses, and publication bias were examined. RESULTS: A total of 19 studies were included for analysis. Significant associations with the risk of IS were detected for the rs3918242 polymorphism in overall population, Asians, and whites. When available data were stratified by gender, we found a significant correlation with the risk of IS in both males and females. Further subgroup analysis by the subtypes of IS showed that the rs3918242 polymorphism was significantly correlated with the risk of patients with large artery atherosclerosis. When stratified by age, we found that the rs3918242 polymorphism was significantly correlated with the risk of IS in patients both aged ≥65 years and >65 years. Both the diabetes and the nondiabetes subgroups reached significant results, and in an analysis stratified by smoking status, an increased risk of IS was associated with smoking. CONCLUSIONS: The rs3918242 polymorphism may be a susceptible predictor of susceptibility of IS. Further large-scale studies are needed to verify the results of our findings.


Assuntos
Isquemia Encefálica/genética , Metaloproteinase 9 da Matriz/genética , Polimorfismo de Nucleotídeo Único , Adulto , Distribuição por Idade , Idoso , Aterosclerose/epidemiologia , Isquemia Encefálica/enzimologia , Isquemia Encefálica/epidemiologia , Estudos de Casos e Controles , Fumar Cigarros/epidemiologia , Comorbidade , Intervalos de Confiança , Diabetes Mellitus/epidemiologia , Grupos Étnicos , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Embolia Intracraniana/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Distribuição por Sexo
2.
Neurol Res ; 41(5): 446-455, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30759063

RESUMO

BACKGROUND: Post-stroke depression (PSD) is one of the most prevalent emotional disorders after stroke and often results in poor outcomes. However, the underlying physiopathologic mechanism and effective treatment of PSD remain poorly elucidated. OBJECTIVE: To investigate whether paeoniflorin has antidepressant-like activity in a rat model of PSD. METHODS: Rats were randomly divided into four groups: sham-operated control (Sham), PSD, paeoniflorin (with PSD) and fluoxetine group(with PSD). PSD was developed by the right middle cerebral artery occlusion followed 21 days chronic unpredictable mild stress combined (CUMS) with raised alone. Tests of sucrose preference and open field were used to assess the depression-like behavior. Neurological function was evaluated by neurological deficit score and beam balance test. Expression of phosphorylated CREB (p-CREB) and brain-derived neurotrophic factor (BDNF) in the CA1 region of the hippocampal complex was evaluated by western blot and immunofluorescence. RESULTS: Te depressive-like behaviors markedly improved after paeoniflorin and fluoxetine treatment. Furthermore, paeoniflorin treatment significantly increased BDNF and p-CREB expression in the CA1 region. CONCLUSIONS: Observed results suggested that paeoniflorin could ameliorate the symptoms and improve the functional capability of PSD rats, similar to the effect of fluoxetine. ABBREVIATIONS: PSD: post-stroke depression; CUMS: chronic unpredictable mild stress stimulation; MCAO: middle cerebral artery occlusion; OFT: open field test; SPT: sucrose preference test, NDS: neurological deficit score, BBT: beam balance test; BDNF: brain-derived neurotrophic factor protein; p-CREB: phosphorylated Cyclic-AMP responsive element binding protein.


Assuntos
Antidepressivos/farmacologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/etiologia , Glucosídeos/farmacologia , Monoterpenos/farmacologia , Acidente Vascular Cerebral/complicações , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Transtorno Depressivo/patologia , Transtorno Depressivo/fisiopatologia , Modelos Animais de Doenças , Fluoxetina/farmacologia , Masculino , Distribuição Aleatória , Ratos Sprague-Dawley , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/patologia , Estresse Psicológico/fisiopatologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia
3.
Neurosci Lett ; 699: 177-183, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30753912

RESUMO

Axon regeneration after cerebral ischemia in mammals is inadequate to restore function, illustrating the need to design better strategies for improving outcomes. Improvement of axon regeneration has been achieved through fastigial nucleus electrostimulation (FNS) in animal researches. However, the mechanisms underlying this neuroprotection remain poorly understood. Increasing the levels of the second messenger cyclic AMP (cAMP) enhances axon regeneration, making it an excellent candidate molecule that has therapeutic potential. In the present study, we examined the expression of cAMP signaling in ischemic brain tissues following focal cerebral ischemia. Adult rats were subjected to ischemia induced by middle cerebral artery occlusion (MCAO). A dipolar electrode was placed into the cerebellum to stimulate the cerebellar fastigial nucleus for 1 h after ischemia. Neurological deficits and the expressions of cAMP, PKA (protein kinase A) and ROCK (Rho-kinase) were determined. Axonal regeneration was measured by upregulation of growth-associated protein 43 (GAP43). The data indicated that FNS significantly enhanced axonal regeneration and motor function recovery after cerebral ischemia. FNS also significantly increased cAMP and PKA levels after ischemic brain injury. All the beneficial effects of FNS were blocked by Rp-cAMP, an antagonist of PKA. Our research suggested that the axonal regeneration conferred by FNS was likely achieved via the regulation of cAMP/PKA pathway.


Assuntos
Núcleos Cerebelares/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Terapia por Estimulação Elétrica , Infarto da Artéria Cerebral Média/terapia , Regeneração Nervosa , Transdução de Sinais , Animais , Núcleos Cerebelares/efeitos dos fármacos , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Proteína GAP-43/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Regeneração Nervosa/efeitos dos fármacos , Ratos , Recuperação de Função Fisiológica/efeitos dos fármacos , Tionucleotídeos/farmacologia , Regulação para Cima , Quinases Associadas a rho/biossíntese
4.
J Colloid Interface Sci ; 434: 98-103, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25170602

RESUMO

We describe the transformation of a colloidal photonic crystal into a photonic crystal heterostructure. It was achieved by annealing a polystyrene multilayer colloidal photonic crystal partially immersed in water using a solvent vapor. The floating polystyrene colloidal photonic crystal was divided into two parts by the liquid level, which can be manipulated by the addition of ethanol into the water. The top part protruding out of the water experienced a uniform lattice stretching upon exposure to the solvent vapor. The bottom part that stayed immersed in the water remained unaffected due to the protection by the water. The inconsistent behaviors of the two parts resulted in the formation of a colloidal photonic crystal heterostructure. Such a heterostructure was free of interface imperfection since it was a direct descendant of the original colloidal crystal. Meanwhile, optical measurements demonstrated the presence of a wider photonic band gap along the crystallographic [111] direction in these photonic crystal heterostructures compared with the original colloidal photonic crystals.

5.
Opt Express ; 20(19): 21618-26, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-23037280

RESUMO

We demonstrate the physical mechanism of optical Tamm states using the phase properties of the photonic crystals. Based on such mechanism, we propose an efficient way that can precisely produce optical Tamm states at specific frequencies. Moreover, we show that dielectric photonic crystals and single-negative materials can be effectively connected through their reflection phase. Two kinds of one-dimensional dielectric photonic crystals with different single-negative characteristics are designed and repeated alternately to construct a superlattice structure. The band structures and the transmission spectra of this superlattice show that multiple optical Tamm states arise and these Tamm states are coupled with each other to form transmission bands. A special zero-effective-phase gap can also be observed in such superlattice.

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