Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Cell Death Discov ; 10(1): 368, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155286

RESUMO

Autophagosome-lysosome fusion defects play a critical role in driving autolysosomal dysfunction, leading to autophagic/lysosomal impairment in neurons following ischemic stroke. However, the mechanisms hindering autophagosome-lysosome fusion remain unclear. Soluble N-ethylmaleimide-sensitive factor (NSF) is an essential ATPase to reactivate STX17 and VAMP8, which are the paired molecules to mediate fusion between autophagosomes and lysosomes. However, NSF is frequently inactivated to inhibit the reactivation of STX17 and VAMP8 in ischemic neurons. Herein, we investigated whether autophagosome-lysosome fusion could be facilitated to alleviate autophagic/lysosomal impairment in ischemic neurons by over-expressing NSF. Rat model of middle cerebral artery occlusion (MCAO) and HT22 neuron ischemia model of oxygen-glucose deprivation (OGD) were prepared, respectively. The results demonstrated that NSF activity was significantly suppressed, accompanied by reduced expressions of STX17 and VAMP8 in penumbral neurons 48 h post-MCAO and in HT22 neurons 2 h post-OGD. Moreover, the attenuated autolysosome formation accompanied by autophagic/lysosomal dysfunction was observed. Thereafter, NSF activity in HT22 neurons was altered by over-expression and siRNA knockdown, respectively. After transfection with recombinant NSF-overexpressing lentiviruses, both STX17 and VAMP8 expressions were concurrently elevated to boost autophagosome-lysosome fusion, as shown by enhanced immunofluorescence intensity co-staining with LC3 and LAMP-1. Consequently, the OGD-created autophagic/lysosomal dysfunction was prominently ameliorated, as reflected by augmented autolysosomal functions and decreased autophagic substrates. By contrast, NSF knockdown conversely aggravated the autophagic/lysosomal impairment, and thereby exacerbated neurological damage. Our study indicates that NSF over-expression induces neuroprotection against ischemic neuronal injury by restoring autophagic/lysosomal dysfunction via the facilitation of autophagosome-lysosome fusion. Over-expression of NSF promotes fusion by reactivating STX17 and VAMP8. Black arrows represent the pathological process after cerebral ischemia, green arrows represent the mechanism of remission after NSF over-expression, and red arrows represent the effect on the pathological process after NSF knockdown.

2.
Cell Signal ; 121: 111301, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39019338

RESUMO

Ischemic stroke is one of the most disabling and fatal diseases around the world. The damaged brain tissues will undergo excessive autophagy, vascular endothelial cells injury, blood-brain barrier (BBB) impairment and neuroinflammation after ischemic stroke. However, there is no unified viewpoint on the underlying mechanism of brain damage. Transforming growth factor-ß1 (TGF-ß1), as a multi-functional cytokine, plays a crucial role in the intricate pathological processes and helps maintain the physiological homeostasis of brain tissues through various signaling pathways after ischemic stroke. In this review, we summarize the protective role of TGF-ß1 in autophagic flux, BBB, vascular remodeling, neuroinflammation and other aspects after ischemic stroke. Based on the review, we believe that TGF-ß1 could serve as a key target for treating ischemic stroke.


Assuntos
Autofagia , Barreira Hematoencefálica , AVC Isquêmico , Fator de Crescimento Transformador beta1 , Humanos , Fator de Crescimento Transformador beta1/metabolismo , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Animais , Barreira Hematoencefálica/metabolismo , Transdução de Sinais , Células Endoteliais/metabolismo , Isquemia Encefálica/metabolismo
3.
Sheng Li Xue Bao ; 76(1): 97-104, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38444135

RESUMO

Autophagy is a metabolic process in which damaged organelles, obsolete proteins, excess cytoplasmic components, and even pathogens are presented to lysosomes for degradation via autophagosomes. It includes 4 processes: the initiation of autophagy, the formation of autophagosomes, the fusion of autophagosomes with lysosomes, and the degradation and removal of autophagic substrates within autophagic lysosomes. When these processes are continuous, it is called autophagy flux. Blockage of one or certain steps in the autophagy/lysosome signaling pathway can lead to impaired autophagy flux. Numerous studies have shown that impaired autophagy flux is an important cause of neuronal damage in the ischemic penumbra after stroke. This paper summarized research progress in the pathological mechanisms that cause impaired neuronal autophagy flux after ischemic stroke and discusses methods to improve neuronal autophagy flux, in order to provide a reference for an in-depth investigation of the pathological injury mechanisms after stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Autofagia , Lisossomos , Cognição
4.
Am J Chin Med ; 52(1): 231-252, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328828

RESUMO

Berberine has been demonstrated to alleviate cerebral ischemia/reperfusion injury, but its neuroprotective mechanism has yet to be understood. Studies have indicated that ischemic neuronal damage was frequently driven by autophagic/lysosomal dysfunction, which could be restored by boosting transcription factor EB (TFEB) nuclear translocation. Therefore, this study investigated the pharmacological effects of berberine on TFEB-regulated autophagic/lysosomal signaling in neurons after cerebral stroke. A rat model of ischemic stroke and a neuronal ischemia model in HT22 cells were prepared using middle cerebral artery occlusion (MCAO) and oxygen-glucose deprivation (OGD), respectively. Berberine was pre-administered at a dose of 100[Formula: see text]mg/kg/d for three days in rats and 90[Formula: see text][Formula: see text]M in HT22 neurons for 12[Formula: see text]h. 24[Formula: see text]h after MCAO and 2[Formula: see text]h after OGD, the penumbral tissues and OGD neurons were obtained to detect nuclear and cytoplasmic TFEB, and the key proteins in the autophagic/lysosomal pathway were examined using western blot and immunofluorescence, respectively. Meanwhile, neuron survival, infarct volume, and neurological deficits were assessed to evaluate the therapeutic efficacy. The results showed that berberine prominently facilitated TFEB nuclear translocation, as indicated by increased nuclear expression in penumbral neurons as well as in OGD HT22 cells. Consequently, both autophagic activity and lysosomal capacity were simultaneously augmented to alleviate the ischemic injury. However, berberine-conferred neuroprotection could be greatly counteracted by lysosomal inhibitor Bafilomycin A1 (Baf-A1). Meanwhile, autophagy inhibitor 3-Methyladenine (3-MA) also slightly neutralized the pharmacological effect of berberine on ameliorating autophagic/lysosomal dysfunction. Our study suggests that berberine-induced neuroprotection against ischemic stroke is elicited by enhancing autophagic flux via facilitation of TFEB nuclear translocation in neurons.


Assuntos
Berberina , Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Ratos , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Autofagia , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia
5.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 38(5): 412-418, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35603649

RESUMO

Objective To investigate the efficacy and mechanism of c-Jun N-terminal kinase (JNK) in boosting survival of oxygen glucose deprivation (OGD) rat neurons. Methods The cortex neurons from fetal rats were primarily cultured to prepare a model of OGD neurons in vitro, and the characteristic endpoints were filtered to intervene with JNK inducer anisomycin (AN), respectively. The cells were randomly divided into control group, solvent control group (a same volume of solvent DMSO was added into the culture medium of the OGD neuron), AN group (OGD neurons were treated with JNK inducer AN for 5 hours at the end of OGD). After that, Western blotting and immunofluorescence cytometry were respectively performed to detect the protein expressions in OGD neurons, including beclin 1, microtubule-associated protein 1 light chain 3 (LC3), B cell lymphoma 2 (Bcl2), caspase-3, P62, ubiquitin, cathepsin B and lysosomal associated membrane protein 1 (LAMP1). The cell activity was evaluated by CCK-8 assay, and the axon length was measured by IPP software. Results Activation of JNK significantly promoted the expressions of beclin 1, LC3, and Bcl2, and markedly reduced the content of beclin 1-Bcl2 complex and attenuated the expressions of P62 and ubiquitin. Meanwhile, the expressions of cathepsin B and LAMP1 were not obviously altered. In this way, the survival rate of OGD neurons was improved. Conclusion Activation of JNK exerts a neuroprotective effect by facilitating dissociation of beclin 1-Bcl2 and inducing a switch from apoptosis to autophagy in OGD neurons.


Assuntos
Oxigênio , Traumatismo por Reperfusão , Animais , Apoptose , Autofagia , Proteína Beclina-1/metabolismo , Catepsina B/metabolismo , Sobrevivência Celular , Glucose/metabolismo , Glicogênio/metabolismo , Glicogênio/farmacologia , Neurônios/metabolismo , Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Traumatismo por Reperfusão/metabolismo , Solventes/metabolismo , Solventes/farmacologia , Ubiquitina/metabolismo
6.
Life (Basel) ; 11(9)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34575099

RESUMO

Autophagic/lysosomal dysfunction is a critical pathogenesis of neuronal injury after ischemic stroke. Trehalose has been validated to restore the impaired autophagy flux by boosting transcription factor EB (TFEB) nuclear translocation, but orally administrated trehalose can be greatly digested by intestinal trehalase before entering into brain. Melibiose (MEL), an analogue of trehalose, may thoroughly exert its pharmacological effects through oral administration due to absence of intestinal melibiase. The present study was to investigate whether melibiose could also confer a neuroprotection by the similar pharmacological mechanism as trehalose did after ischemic stroke. The rats were pretreated with melibiose for 7 days before middle cerebral artery occlusion (MCAO) surgery. Twenty-four hours following MCAO/reperfusion, the cytoplasmic and nuclear TFEB, and the proteins in autophagic/lysosomal pathway at the penumbra were detected by western blot and immunofluorescence, respectively. Meanwhile, the neurological deficit, neuron survival, and infarct volume were assessed to evaluate the therapeutic outcomes. The results showed that the neurological injury was significantly mitigated in MCAO+MEL group, compared with that in MCAO group. Meanwhile, nuclear TFEB expression in neurons at the penumbra was significantly promoted by melibiose. Moreover, melibiose treatment markedly enhanced autophagy flux, as reflected by the reinforced lysosomal capacity and reduced autophagic substrates. Furthermore, the melibiose-elicited neuroprotection was prominently counteracted by lysosomal inhibitor Bafilomycin A1 (Baf-A1). Contrarily, reinforcement of lysosomal capacity with EN6 further improved the neurological performance upon melibiose treatment. Our data suggests that melibiose-augmented neuroprotection may be achieved by ameliorating autophagy flux via facilitation of TFEB nuclear translocation in neurons after ischemic stroke.

7.
Curr Med Sci ; 41(4): 803-814, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34403106

RESUMO

OBJECTIVE: Autophagy was prominently activated by cerebral ischaemia. This study was to investigate the exact role of autophagy in ischaemic stroke. METHODS: Two rat models of transient middle cerebral artery occlusion (tMCAO) and permanent MCAO (pMCAO) were prepared. The brain tissues in the penumbra were obtained to observe the dynamic variations of autophagy activity with Beclin1 and LC3 antibodies by Western blotting. At the characteristic time points, when autophagy activity was markedly elevated or reduced, the autophagy activation signaling was intervened with rapamycin and 3-methyladenine, respectively. Thereafter, key proteins in the autopahgic/lysosomal pathway were detected with the antibodies of LC3, p62, ubiquitin, LAMP-1 and cathepsin B. Meanwhile, TTC staining, neurological score and immunofluorescence were performed to evaluate brain infarct volume, neurological deficit and neuron survival, respectively. RESULTS: Both Beclin1 and LC3 expression levels were remarkably altered at 6 h, 12 h, 2 days and 7 days after tMCAO. Interestingly, the dynamic changes of autophagy activity following pMCAO were identical to those after tMCAO. Neither autophagy induction nor autophagy inhibition was able to ameliorate the pMCAO-induced neurological injury due to lysosomal dysfunction, as indicated by low levels of LAMP-1 and cathepsin B, accompanied with the accumulation of LC3-II, ubiquitin and insoluble p62. Comparatively, autophagy induction elicited overt neuroprotection at 2 and 7 days after tMCAO, and this neuroprotection might be elicited by the enhancement of autophagy flux. CONCLUSION: Our study suggests that autophagy confers neuroprotection at the subacute phase of tMCAO but has few effects on neurological outcomes after pMCAO.


Assuntos
Autofagia/genética , Encéfalo/metabolismo , Ataque Isquêmico Transitório/metabolismo , AVC Isquêmico/metabolismo , Neurônios/metabolismo , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Humanos , Infarto da Artéria Cerebral Média , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/patologia , AVC Isquêmico/genética , AVC Isquêmico/patologia , Lisossomos/genética , Lisossomos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Neurônios/patologia , Neuroproteção/genética , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteína Sequestossoma-1/genética , Transdução de Sinais/genética
8.
Neural Regen Res ; 16(5): 813-819, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33229714

RESUMO

Autophagy is crucial for maintaining cellular homeostasis, and can be activated after ischemic stroke. It also participates in nerve injury and repair. The purpose of this study was to investigate whether an enriched environment has neuroprotective effects through affecting autophagy. A Sprague-Dawley rat model of transient ischemic stroke was prepared by occlusion of the middle cerebral artery followed by reperfusion. One week after surgery, these rats were raised in either a standard environment or an enriched environment for 4 successive weeks. The enriched environment increased Beclin-1 expression and the LC3-II/LC3-I ratio in the autophagy/lysosomal pathway in the penumbra of middle cerebral artery-occluded rats. Enriched environment-induced elevations in autophagic activity were mainly observed in neurons. Enriched environment treatment also promoted the fusion of autophagosomes with lysosomes, enhanced the lysosomal activities of lysosomal-associated membrane protein 1, cathepsin B, and cathepsin D, and reduced the expression of ubiquitin and p62. After 4 weeks of enriched environment treatment, neurological deficits and neuronal death caused by middle cerebral artery occlusion/reperfusion were significantly alleviated, and infarct volume was significantly reduced. These findings suggest that neuronal autophagy is likely the neuroprotective mechanism by which an enriched environment promotes recovery from ischemic stroke. This study was approved by the Animal Ethics Committee of the Kunming University of Science and Technology, China (approval No. 5301002013855) on March 1, 2019.

9.
J Patient Exp ; 7(5): 801-806, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33294618

RESUMO

Patient satisfaction studies have gained more and more attention, and there are many patient satisfaction studies. These studies assume that patients were selected randomly and independently, but patient satisfaction surveys are described as a multistage or hierarchically structured sample. Thus, there is a need to conduct a hierarchical linear model (HLM) analysis with a large number of hospitals. This study utilized an HLM to investigate both the individual patient-level effect on the overall satisfaction rating and the effect of hospital characteristics on the combining process of patient's overall satisfaction rating. This study used patient satisfaction data collected from 100 hospitals with the sample size of 85 766. The hospital-level characteristics include total expense per personnel, payroll expense per personnel, number of staffed beds per personnel, and number of admission per personnel. This study found that hospital characteristics influence overall rating of the hospital through the doctor, staff, and room attributes. When considering the complex nature of the overall patient rating process of hospitals, it makes more sense to analyze hospital characteristics that are interacting with attributes rather than treat hospital characteristics as independent of these factors.

10.
Neural Regen Res ; 14(2): 280-288, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30531011

RESUMO

Ischemic stroke often induces excessive neuronal autophagy, resulting in brain damage; meanwhile, inflammatory responses stimulated by ischemia exacerbate neural injury. However, interactions between neuronal autophagy and microglial inflammation following ischemic stroke are poorly understood. CX3CL1/fractalkine, a membrane-bound chemokine expressed on neurons, can suppress microglial inflammation by binding to its receptor CX3CR1 on microglia. In the present study, to investigate whether autophagy could alter CX3CL1 expression on neurons and consequently change microglial inflammatory activity, middle cerebral artery occlusion (MCAO) was established in Sprague-Dawley rats to model ischemic stroke, and tissues from the ischemic penumbra were obtained to evaluate autophagy level and microglial inflammatory activity. MCAO rats were administered 3-methyladenine (autophagy inhibitor) or Tat-Beclin 1 (autophagy inducer). Western blot assays were conducted to quantify expression of Beclin-1, nuclear factor kappa B p65 (NF-κB), light chain 3B (LC3B), and CX3CL1 in ischemic penumbra. Moreover, immunofluorescence staining was performed to quantify numbers of LC3B-, CX3CL1-, and Iba-1-positive cells in ischemic penumbra. In addition, enzyme linked immunosorbent assays were utilized to analyze concentrations of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 1 beta (IL-1ß), and prostaglandin E2 (PGE2). A dry/wet weight method was used to detect brain water content, while 2,3,5,-triphenyltetrazolium chloride staining was utilized to measure infarct volume. The results demonstrated that autophagy signaling (Beclin-1 and LC3B expression) in penumbra was prominently activated by MCAO, while CX3CL1 expression on autophagic neurons was significantly reduced and microglial inflammation was markedly activated. However, after inhibition of autophagy signaling with 3-methyladenine, CX3CL1 expression on neurons was obviously increased, whereas Iba-1 and NF-κB expression was downregulated; TNF-α, IL-6, IL-1ß, and PGE2 levels were decreased; and cerebral edema was obviously mitigated. In contrast, after treatment with the autophagy inducer Tat-Beclin 1, CX3CL1 expression on neurons was further reduced; Iba-1 and NF-κB expression was increased; TNF-α, IL-6, IL-1ß, and PGE2 levels were enhanced; and cerebral edema was aggravated. Our study suggests that ischemia-induced neuronal autophagy facilitates microglial inflammatory injury after ischemic stroke, and the efficacy of this process may be associated with downregulated CX3CL1 expression on autophagic neurons.

11.
Stat Med ; 37(4): 590-597, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29044583

RESUMO

Archimedean copulas are commonly used in a wide range of statistical models due to their simplicity, manageable analytical expressions, rich choices of generator functions, and other workable properties. However, the exchangeable dependence structure inherent to Archimedean copulas limits its application to familial data, where the dependence among family members is often different. When response variables are binary, modeling the familial associations becomes more challenging due to the stringent constraints imposed on the dependence parameters. This paper proposes hierarchical Archimedean copulas to account for the natural hierarchical dependence structure in familial data and addresses the details in the modeling of binary familial data and the inference based on maximum likelihood estimate. An example showing the flexibility of this powerful tool is also presented with possible extension to other similar studies.


Assuntos
Família , Modelos Estatísticos , Trifosfato de Adenosina/sangue , Bioestatística , Análise Química do Sangue/estatística & dados numéricos , Simulação por Computador , Feminino , Humanos , Funções Verossimilhança , Masculino , Análise Multivariada
12.
Brain Inj ; 31(8): 1151-1158, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28506087

RESUMO

OBJECTIVE: Autophagy and apoptosis coexist in stroke, but the relationship between effects and complex is poorly understood. Herein, we investigated dynamic changes of autophagy and apoptosis at the penumbra in permanent cerebral ischaemia. METHODS: Sprague-Dawley rat models were prepared by middle cerebral artery occlusion. The autophagy and apoptosis were evaluated by Western blotting and immunofluorescence with LC3-II and cleaved caspase-3, respectively. The neurological deficit score and infarct volume were assessed. RESULTS: The results showed that the expressions of LC3-II and cleaved caspase-3 were gradually increased from 1 to 5 hours, and reached maximum at 5 hours after stroke. After that, LC3-II expression was significantly declined, but cleaved caspase-3 expression was only mildly reduced from 6 hours to 3 days. Surprisingly, at 4 days after stroke, the autophagy was abruptly increased again, but the apoptosis was considerably and continuously decreased. The severity of the neurological deficit was in accordance with the increase of infarct expansion. CONCLUSIONS: Our results showed that autophagy and apoptosis were simultaneously activated within 12 hours after stroke. Four days later, LC3-II expression was significantly increased, while cleaved caspase-3 expression was considerably decreased, implying that there might be a transition from apoptosis to autophagy at the subacute phase of stroke.


Assuntos
Apoptose/fisiologia , Autofagia/fisiologia , Encéfalo/fisiologia , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Animais , Encéfalo/metabolismo , Infarto Encefálico/etiologia , Caspase 3/metabolismo , Modelos Animais de Doenças , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Exame Neurológico , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
Am J Phys Med Rehabil ; 96(3): e36-e43, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27977432

RESUMO

OBJECTIVE: Exercise is an effective, inexpensive, home-based, and accessible intervention strategy for stroke treatment, and early exercise after stroke has attracted a great deal of attention in recent years. However, the effects of early exercise on comprehensive functional recovery remain poorly understood. The present study investigated the effect of early exercise on motor, sense, balance, and spatial memory recovery. DESIGN: Adult Sprague-Dawley rats were subjected to unilateral middle cerebral artery occlusion (MCAO) and were randomly divided into early exercise group (EE), non-exercise group (NE), and sham group. EE group received 2 weeks of exercise training initiated at 24 hours after operation. The recovery of motor, sense, and balance function was evaluated every 3 days after MCAO. Spatial memory recovery was detected from 21 to 25 days after MCAO. RESULTS: The results showed that early exercise significantly promoted the motor and spatial memory recovery with statistical differences. The rats in EE group have a better recovery in sense and balance function, but there is no statistically significant difference about these results. CONCLUSION: Our results showed that early moderate exercise can significantly promote motor and spatial memory recovery, but not the sense and balance functions.


Assuntos
Condicionamento Físico Animal , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Modelos Animais de Doenças , Atividade Motora/fisiologia , Equilíbrio Postural/fisiologia , Ratos Sprague-Dawley , Memória Espacial/fisiologia
14.
Neural Regen Res ; 11(7): 1108-14, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27630694

RESUMO

The temporal dynamics of neuronal autophagy and apoptosis in the ischemic penumbra following stroke remains unclear. Therefore, in this study, we investigated the dynamic changes in autophagy and apoptosis in the penumbra to provide insight into potential therapeutic targets for stroke. An adult Sprague-Dawley rat model of permanent ischemic stroke was prepared by middle cerebral artery occlusion. Neuronal autophagy and apoptosis in the penumbra post-ischemia were evaluated by western blot assay and immunofluorescence staining with antibodies against LC3-II and cleaved caspase-3, respectively. Levels of both LC3-II and cleaved caspase-3 in the penumbra gradually increased within 5 hours post-ischemia. Thereafter, levels of both proteins declined, especially LC3-II. The cerebral infarct volume increased slowly 1-4 hours after ischemia, but subsequently increased rapidly until 5 hours after ischemia. The severity of the neurological deficit was positively correlated with infarct volume. LC3-II and cleaved caspase-3 levels were high in the penumbra within 5 hours after ischemia, and after that, levels of these proteins decreased at different rates. LC3-II levels were reduced to a very low level, but cleaved caspase-3 levels remained high 72 hours after ischemia. These results indicate that there are temporal differences in the activation status of the autophagic and apoptotic pathways. This suggests that therapeutic targeting of these pathways should take into consideration their unique temporal dynamics.

15.
Health Mark Q ; 31(4): 370-82, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405636

RESUMO

Most patient satisfaction studies put an emphasis on finding key drivers (attribute) to increase overall patient satisfaction. However, it is not clear how much health care managers need to improve certain attributes to attain the target overall patient satisfaction level. The study aims at finding not only what attributes, but also how much these attributes need to be improved to attain the target levels of patient satisfaction. The study uses an ordinal logistic regression model to analyze attribute reactions to salient drivers. This approach would significantly enhance health care managers' capabilities to develop a strategic plan to improve their patient satisfaction levels.


Assuntos
Modelos Logísticos , Satisfação do Paciente , Qualidade da Assistência à Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Inquéritos e Questionários
16.
J Microbiol Immunol Infect ; 47(1): 48-56, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23357605

RESUMO

BACKGROUND: We previously constructed a recombinant bacille Calmette-Guérin (rBCG-AE) strain that could express a fused Ag85A-ESAT-6 protein. That study suggested that the rBCG-AE strain was able to induce a higher titer of antibody and elicit a more long-lived and stronger Th1-type cellular immune responses than the parental BCG strain, the rBCG-A strain (i.e., expressing Ag85A), or the rBCG-E strain (i.e., expressing ESAT-6). METHODS: In the current study, we further investigated the strain's protective efficacy against Mycobacterium tuberculosis H37Rv infection in BALB/c mice through evaluating organ bacterial loads, lung histopathology, lung immunohistochemistry, and net weight gain or loss by using conventional BCG, rBCG-A, and rBCG-E as the controls. RESULTS: From the 3rd to 9th weeks after the challenge infection, the bacterial counts were significantly lower in tissues (e.g., spleen and lung tissues) in the mice immunized with rBCG-AE than in the control group, but were higher than the counts in the BCG group. The pathological damage in the lung tissues of the rBCG-AE group gradually improved from the 6th to 9th weeks after being infected with M. tuberculosis H37Rv, but the score of pathological changes in the rBCG-AE group was obviously higher than the score in the BCG group. There was no difference in the percentage of IFN-γ and iNOS positive cells in the lung tissues of the rBCG-AE and BCG groups. CONCLUSION: The results suggest that rBCG-AE can not promote protective efficacy against M. tuberculosis H37Rv infection, compared to the BCG vaccine.


Assuntos
Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Proteínas de Bactérias/imunologia , Tuberculose/prevenção & controle , Aciltransferases/genética , Animais , Antígenos de Bactérias/genética , Vacina BCG/administração & dosagem , Vacina BCG/genética , Carga Bacteriana , Proteínas de Bactérias/genética , Peso Corporal , Feminino , Histocitoquímica , Imuno-Histoquímica , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/isolamento & purificação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Tuberculose/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
17.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 30(4): 817-21, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24059063

RESUMO

To obtain a vaccine to defend from dormancy Mycobacterium tuberculosis, we constructed the recombinant Bacilli Calmette-Guérin (BCG) vaccine with Rv3133c encoding dormancy-correlated transcriptional regulatory protein DosR in Mycobacterium tuberculosis as a target gene, and evaluated its immunogenicity in BALB/c mice. In this study, we constructed the recombinant plasmids of rpMV361-Rv3133c using gene colon technology. We then transformed BCG strains with above-mentioned plasmids to obtain recombinant vaccine of rBCG-Rv3133c. We used the rBCG strains successfully constructed to vaccinate in BALB/c mice. 30d and 180d after immunization, the specific antibody titers were determined to investigate humoral responses induced by recombinant vaccine. We detected changes of splenocyte subsets of CD4+T, CD8+ T cells and cytokine of IFN-gamma secreted by splenocytes for evaluation of cellular immune responses. The results showed that the rBCG-Rv3133c was able to induce higher levels of antibody titer, stronger proliferative responses and higher IFN-gamma production comparing with BCG vaccine. The results also suggested that this recombinant vaccine was a more efficacious tuberculosis vaccine for further study.


Assuntos
Antígenos de Bactérias/genética , Vacina BCG/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Proteínas Quinases/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA , Escherichia coli/genética , Escherichia coli/metabolismo , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases/genética , Proteínas Recombinantes/imunologia , Subpopulações de Linfócitos T/imunologia , Tuberculose/prevenção & controle , Vacinação , Vacinas Sintéticas/imunologia
18.
Microbiol Immunol ; 55(11): 798-808, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21831202

RESUMO

ESAT-6 protein of Mycobacterium tuberculosis is absent in Mycobacterium bovis BCG and Mycobacterium microti and has been demonstrated to stimulate strong cell-mediated immunity. IL-12 can play crucial roles in regulating IFN-γ production and Th1 effectors production. In this study, we constructed three rBCG vaccines that could express proteins of human IL-12p70 and/or ESAT-6 and evaluated their immunogenicity and protective efficacy in mice. Our experiments illustrated that the rBCG-IE (expressing a fusion protein of human IL-12p70 and ESAT-6) was capable of inducing stronger Th1 type cell-mediated immune responses than conventional BCG, or rBCG-I (expressing human IL-12p70), or rBCG-E (expressing ESAT-6). However, the results of protective experiments showed that rBCG-IE could only confer similar and even lower protective efficacy against M. tuberculosis H37Rv infection compared with BCG vaccine.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium bovis/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinas Sintéticas/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Carga Bacteriana , Proteínas de Bactérias/genética , Peso Corporal , Modelos Animais de Doenças , Feminino , Histocitoquímica , Imunoglobulina G/sangue , Interleucina-12/genética , Interleucina-12/imunologia , Leucócitos Mononucleares/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium bovis/genética , Mycobacterium tuberculosis/isolamento & purificação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Baço/imunologia , Baço/microbiologia , Células Th1/imunologia , Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Vacinas Sintéticas/administração & dosagem
19.
Acta Biochim Biophys Sin (Shanghai) ; 43(7): 511-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21676888

RESUMO

Since Mycobacterium bovis bacillus Calmette-Guerin strain (BCG) fails to protect adults from pulmonary tuberculosis (TB), there is an urgent need for developing a new vaccine. In this study, we constructed a novel recombinant BCG strain (rBCG) expressing human granulocyte macrophage colony-stimulating factor (GM-CSF) and the 6 kDa early secretory antigenic target (ESAT6) of Mycobacterium tuberculosis, named rBCG:GE (expressing GMCSF-ESAT6 complex), and evaluated the immunogenicity of the construct in BALB/c mice. Our results indicated that the rBCG:GE was able to induce higher titer of antibody than the conventional BCG, the rBCG:G (expressing GM-CSF) and the rBCG:E (expressing ESAT6). Moreover, the rBCG:GE also elicited a longer-lasting and stronger Th1 cellular immune responses than the other groups, which was confirmed by the incremental proliferation of splenocytes, the increased percentages of CD4(+) and CD8(+) T cells of spleen, the elevated level of interferon-γ in splenocyte culture after tuberculin-purified protein derivative stimulation, and the increased concentration of GM-CSF in serum. The data presented here suggested the possibility that the recombinant BCG:GE might be a good vaccine candidate to TB.


Assuntos
Antígenos de Bactérias/biossíntese , Vacina BCG/imunologia , Proteínas de Bactérias/biossíntese , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Mycobacterium bovis/imunologia , Células Th1/imunologia , Adulto , Animais , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Camundongos , Mycobacterium tuberculosis/imunologia , Proteínas Recombinantes/imunologia , Vacinas contra a Tuberculose/biossíntese
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(6): 936-9, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19253830

RESUMO

OBJECTIVE: To establish an alcoholic liver disease model in rats to study the effect of Hepcidin on the development of alcoholic liver disease. METHODS: Fourty SD rats were randomly divided into 2 groups, 20 for each group. Saline [10 mL/(kg x d)] and 56% ethano infusion [10 mL/(kg x d)] were given orally to the rats for 12 weeks for the control and experimental group, respectively. The serum ALT, AST, and iron, and the superoxide dismutase (SOD) activity and malonaldehyde (MDA) content in the hepatic tissue were determined. RT-PCR was employed to examine the expression of Hepcidin mRNA in the liver. The histopathological changes of the liver tissues were examined through HE, Sudan IV and immunohistochemical stainings. RESULTS: The rats in the experimental group had greater serum ALT, AST and iron, and decreased SOD activity and increased MDA activity than those in the control group (P<0.01). The rats in the experimental group had enlarged livers, with rough surface and grey-yellow color. The rats in the experimental group had more local hepatocellular necrosis, inflammatory cells, and large fat droplets, and larger red tangerine staining sectors in the livers than those in the control group (P<0.05). Higher positive expressions of TNF-alpha and IL-6 in the liver tissues were found in the experimental group than in the control group (P<0.01). The rats in the experimental group had lower levels of mRNA of Hepcidin than those in the control group (P<0.01). CONCLUSION: The rats with alcoholic livers have increased expression of TNF-alpha and IL-6 and decreased expression of Hepcidin in the liver tissues.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Hepatopatias Alcoólicas/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Feminino , Hepcidinas , Interleucina-6/metabolismo , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/patologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA