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1.
Nanoscale ; 12(4): 2345-2349, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31916555

RESUMO

Alloyed bimetallic Pd-Ru nanocatalysts prepared by in situ reduction of a mixture of a Ru(iii) source and a Pd(ii)@alkyne-PVA aerogel and characterized by TEM and XPS exhibit very highly catalytic activity towards hydrogen release from ammonia borane hydrolysis with a TOF value of 578.2 molH2 molcat-1 min-1.

2.
Chemosphere ; 241: 125084, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31627111

RESUMO

In this study, high quality Magnéli phase Ti4O7 bulks with electrical conductivity up to 961.5 S cm-1 were successfully prepared by spark plasma sintering (SPS) and then served as electrode materials for electrochemical oxidation of azo dye methyl orange (MO). The influences of current density and initial dye concentration on the removal rates of MO and chemical oxygen demand (COD) were studied. Removal of MO and COD exhibited an increase with increasing current density and decreasing initial concentration of MO. Complete removal of MO was realized within a short time under all experimental conditions. The removal rate of COD reached 91.7% when current density was 10 mA cm-2 and initial dye concentration was 100 mg L-1. In addition, the electrochemical oxidation rate could be described through a pseudo-first-order kinetic constant k, and the obtained experimental results could be well fitted with a proposed kinetic model in all the examined conditions. Possible degradation mechanisms for electrochemical oxidation of MO by Ti4O7 electrode were proposed on the basis of intermediate products analysis. Tests were also conducted with other commercial electrodes for comparison, including commercial graphite, stainless-steel and dimension stable anode (DSA) electrodes. The results showed that Ti4O7 anode exhibited the fastest electrochemical oxidation rates than those of the other electrodes. This study provides a feasible method for realizing high efficiency of electrochemical oxidation degradation by Ti4O7 electrode.


Assuntos
Compostos Azo/química , Modelos Químicos , Poluentes Químicos da Água/química , Análise da Demanda Biológica de Oxigênio , Eletrodos , Grafite/análise , Cinética , Oxirredução , Titânio/análise , Titânio/química , Poluentes Químicos da Água/análise
3.
J Hazard Mater ; : 121761, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31796359

RESUMO

MXenes, as new members of the 2D materials group, are regarded as good candidates for heavy metal removal particularly for radioactive metal element because of their high irradiation stability. However, the small interlayer distance and lack of active sites on the surface limit their further application. In this report, nanoscale zero-valent iron has been introduced into the inter-layer structure of alkaline intercalated Ti3C2 (Alk-Ti3C2) and investigated to Cr(VI) removal. The XPS spectra, SEM images, TEM images, and N2 adsorption-desorption isotherms characterizations revealed that the OH groups on the Alk-Ti3C2 surface assisted the introducing of nZVI into the inter-layer of Alk-Ti3C2 and subsequently stabilized the nZVI. The increased active sites of nZVI and extended interlayer space of Alk-Ti3C2 could improve the uptake capacity of Cr(VI) (194.87 mg/g at pH = 2). The highly efficient removal of Cr(VI) was maintained even in the presence of coexisting cations, which showed great potential for real environment remediation. Mechanistic study indicated that the synergistic effects of nZVI and Alk-Ti3C2 nanosheet in nZVI-Alk-Ti3C2 composites are keys for Cr(VI) removal.

4.
IEEE Trans Biomed Eng ; 65(1): 219-223, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28463182

RESUMO

Exercise preconditioning induces neuroprotective effects during cerebral ischemia and reperfusion, which involves the recovery of cerebral blood flow (CBF). Mechanisms underlying the neuroprotective effects of re-established CBF following ischemia and reperfusion are unclear. The present study investigated CBF in hyper-early stage of reperfusion by laser speckle contrast imaging, a full-field high-resolution optical imaging technique. Rats with or without treadmill training were subjected to middle cerebral artery occlusion followed by reperfusion. CBF in arteries, veins, and capillaries in hyper-early stage of reperfusion (1, 2, and 3 h after reperfusion) and in subacute stage (24 h after reperfusion) were measured. Neurological scoring and 2,3,5-triphenyltetrazolium chloride staining were further applied to determine the neuroprotective effects of exercise preconditioning. In hyper-early stage of reperfusion, CBF in the rats with exercise preconditioning was reduced significantly in arteries and veins, respectively, compared to rats with no exercise preconditioning. Capillary CBF remained stable in the hyper-early stage of reperfusion, though it increased significantly 24 h after reperfusion in the rats with exercise preconditioning. As a neuroprotective strategy, exercise preconditioning reduced the blood perfusion of arteries and veins in the hyper-early stage of reperfusion, which indicated intervention-induced neuroprotective hypoperfusion after reperfusion onset.


Assuntos
Isquemia Encefálica/fisiopatologia , Circulação Cerebrovascular/fisiologia , Condicionamento Físico Animal/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Algoritmos , Animais , Comportamento Animal , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/patologia , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/diagnóstico por imagem , Traumatismo por Reperfusão/fisiopatologia , Reprodutibilidade dos Testes
5.
Parasit Vectors ; 10(1): 273, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569179

RESUMO

BACKGROUND: Enolase is an essential multifunctional glycolytic enzyme that is involved in many biological processes of apicomplexan protozoa, such as adhesion and invasion. However, the characteristics of enolase in Cryptosporidium parvum, including the location on the oocyst and the enzyme activity, remain unclear. METHODS: The C. parvum enolase gene (cpeno) was amplified by RT-PCR and sequenced. The deduced amino acid sequence was analysed by bioinformatics software. The gene was expressed in Escherichia coli BL21 (DE3) and purified recombinant protein was used for enzyme activity analysis, binding experiments and antibody preparation. The localisation of enolase on oocysts was examined via immunofluorescence techniques. RESULTS: A 1,350 bp DNA sequence was amplified from cDNA taken from C. parvum oocysts. The deduced amino acids sequence of C. parvum enolase (CpEno) had 82.1% homology with Cryptosporidium muris enolase, and 54.7-68.0% homology with others selected species. Western blot analysis indicated that recombinant C. parvum enolase (rCpEno) could be recognised by C. parvum-infected cattle sera. Immunolocalization testing showed that CpEno was found to locate mainly on the surface of oocysts. The enzyme activity was 33.5 U/mg, and the Michaelis constant (K m ) was 0.571 mM/l. Kinetic measurements revealed that the most suitable pH value was 7.0-7.5, and there were only minor effects on the activity of rCpEno with a change in the reaction temperature. The enzyme activity decreased when the Ca2+, K+, Mg2+ and Na+ concentrations of the reaction solution increased. The binding assays demonstrated that rCpEno could bind to human plasminogen. CONCLUSION: This study is the first report of immunolocation, binding activity and enzyme characteristics of CpEno. The results of this study suggest that the surface-associated CpEno not only functions as a glycolytic enzyme but may also participate in attachment and invasion process of the parasite.


Assuntos
Cryptosporidium parvum/enzimologia , Cryptosporidium parvum/genética , Fosfopiruvato Hidratase/genética , Fosfopiruvato Hidratase/imunologia , Fosfopiruvato Hidratase/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/sangue , Sequência de Bases , Bovinos , Criptosporidiose/sangue , Criptosporidiose/imunologia , Criptosporidiose/parasitologia , Cryptosporidium/enzimologia , Cryptosporidium/genética , DNA Complementar , Ensaios Enzimáticos , Escherichia coli/genética , Regulação da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Cinética , Metais , Oocistos/enzimologia , Fosfopiruvato Hidratase/classificação , Filogenia , Plasminogênio , Proteínas de Protozoários/genética , RNA Mensageiro/genética , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Temperatura Ambiente
6.
World J Gastroenterol ; 22(40): 8905-8909, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27833381

RESUMO

Along with the rapid development of society, lifestyles and diets have gradually changed. Due to overwhelming material abundance, high fat, high sugar and high protein diets are common. Numerous studies have determined that diet and its impact on gut microbiota are closely related to obesity and metabolic diseases. Different dietary components affect gut microbiota, thus impacting gastrointestinal disease occurrence and development. A large number of related studies are progressing rapidly. Gut microbiota may be an important intermediate link, causing gastrointestinal diseases under the influence of changes in diet and genetic predisposition. To promote healthy gut microbiota and to prevent and cure gastrointestinal diseases, diets should be improved and supplemented with probiotics.


Assuntos
Dieta Hiperlipídica , Gastroenteropatias/microbiologia , Microbioma Gastrointestinal , Animais , Humanos
7.
World J Gastroenterol ; 22(39): 8806-8811, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27818596

RESUMO

AIM: To investigate correlations between diet and prevalence of constipation among elderly people in Beijing. METHODS: A total of 2776 (≥ 60 years) were selected in Beijing region for investigation. Data regarding constipation and diet habits was collected via hierarchical status, segmentation and random cluster sampling. Investigation included constipation-related demographic indicators and diet habits. Door-to-door questionnaires and surveys included daily staple food intakes, frequency of fish, egg, fruits and vegetables consumption. Constipation was defined according to the China Chronic Constipation Diagnosis and Treatment Guideline (2013), with the following constipation judgment indicators: decreased defecation frequency, dry and hard stool, and difficulty in defecation. RESULTS: The prevalence of constipation among elderly people in Beijing region was 13%. There was a positive correlation between prevalence of constipation and age, but negative correlations between prevalence of constipation and staple food, fish and dietary fibres (fruits and vegetables) intakes. These differences were all statistically significant. CONCLUSION: The prevalence of elderly constipation in Beijing region is closely related to diet habits, and is significantly decreased by high staple foods intake, fish eating and high dietary fibres (fruits and vegetables) consumption.


Assuntos
Constipação Intestinal/diagnóstico , Constipação Intestinal/epidemiologia , Dieta , Idoso , Pequim , China , Demografia , Fibras na Dieta , Estudos Epidemiológicos , Feminino , Produtos Pesqueiros , Frutas , Humanos , Masculino , Pessoa de Meia-Idade , Óvulo , Prevalência , Inquéritos e Questionários , Verduras
8.
Naunyn Schmiedebergs Arch Pharmacol ; 389(6): 573-84, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26935715

RESUMO

Cervical cancer is the second leading cause of cancer deaths in women worldwide. In recent years, the studies find that inflammation is a critical component of tumor progression, and the ideal therapeutic methods should be aimed at the inflammation reaction triggers. (1ß,3ß,5ß,25S)-spirostan-1,3-diol1-[α-L-rhamnopyranosyl-(1 → 2)-ß-D-xylopyranoside] (RCE-4) was the main active composition of Reineckia carnea (Andr.) Kunth. It significantly induced apoptosis in cervical cancer Caski cells through the mitochondrial pathway in our previous studies; however, its underlying mechanism remains poorly understood. This study aimed to further evaluate the effect of RCE-4 on human cervical cancer HeLa cells. Based on this observation, we investigated the anti-cervical cancer effect of RCE-4 by modulating phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway, nuclear factor-kappa B (NF-κB) activation, and inflammation-related key factors in HeLa cells. The results indicated that the HeLa cell was the most sensitive with an IC50 of 7.01 µM; RCE-4 significantly promoted the release of cellular lactate dehydrogenase (LDH); increased DNA fragmentation and apoptosis; reduced PI3K, Akt, mTOR, and NF-κBp65 phosphorylation levels; increased the Bax and cleaved poly (ADP-ribose) polymerase (PARP) protein levels; suppressed Bcl-2 protein expression; elevated the Bax/Bcl-2 expression ratio; and decreased the interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6) mRNA expressions in HeLa cells in a concentration-dependent manner. These findings suggest that RCE-4 exerted beneficially anti-cervical cancer effect on HeLa cells, mainly inhibiting PI3K/Akt/mTOR signaling pathway phosphorylation and NF-κB activation, promoting HeLa cell apoptosis. Graphical abstract Anti-tumor effect of RCE-4 on HeLa cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Saponinas/farmacologia , Espirostanos/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Feminino , Células HeLa , Humanos , Mediadores da Inflamação/metabolismo , Concentração Inibidora 50 , L-Lactato Desidrogenase/metabolismo , Liliaceae/química , Células MCF-7 , Fosforilação , Fitoterapia , Plantas Medicinais , Saponinas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Espirostanos/isolamento & purificação , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/patologia
9.
World J Gastroenterol ; 21(47): 13368-73, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26715822

RESUMO

AIM: To investigate the present situation of elderly constipation in urban and rural areas of the Beijing region. METHODS: A total of 1942 cases (≥ 60 years) were selected in the Beijing region for investigation. Constipation-related data collection was carried out via hierarchical status, segmentation, and random cluster sampling. Patient data concerning constipation-related demographic indicators, education level, occupation, economic status, and history of gastrointestinal disease was obtained via questionnaires and surveys. Constipation was defined according to the Rome III criteria, with the following constipation judgment indicators: defecation less than 3 times per week, stool weight less than 35 g/d, dry and hard stool, and difficulty in defecating during more than 25% of evacuation attempts. RESULTS: Of the 1942 cases, 634 were diagnosed with constipation, and the total prevalence rate was 32.6%, which increased with age. There was a statistically insignificantly higher prevalence of constipation in females (compared to males) and urban areas (compared to rural areas). There was a statistically insignificantly higher prevalence in the illiterate group compared to the literacy group. Those engaged in mental work suffered from statistically significantly higher constipation prevalence than those engaged in physical labor. A total of 1847 cases did not suffer from gastritis, of which 595 cases were constipated; although the prevalence rate was 32.2%, showing a higher incidence of constipation in patients with gastritis, no significant statistical difference between the two groups was found. A total of 59 cases with a past history of biliary tract disease were found, of which 26 had constipation; constipation prevalence was 44.1% (far higher than other groups), which was a statistically significant difference. CONCLUSION: The prevalence of elderly constipation in the Beijing region closely resembles Western countries, and is significantly affected by region, age, and past history of other related illnesses.


Assuntos
Envelhecimento , Constipação Intestinal/epidemiologia , Doença Aguda , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Doença Crônica , Comorbidade , Constipação Intestinal/diagnóstico , Constipação Intestinal/fisiopatologia , Defecação , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Saúde da População Rural , Índice de Gravidade de Doença , Fatores Sexuais , Fatores Socioeconômicos , Saúde da População Urbana
10.
Iran J Public Health ; 44(9): 1187-95, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26587492

RESUMO

BACKGROUND: Rhoptries are unique secretory/excretory organelles that are found exclusively in the Apicomplexa, and their contents are discharged at the time of invasion and are critical in the establishment of productive infection. Several rhoptry proteins have been identified in Toxoplasma gondii, Plasmodium falciparum and Neospora caninum and have been linked not only with the parasites' adhesion and invasion processes but also with their intracellular pathways. To date, only one Cryptosporidium parvum rhoptry protein candidate related to TgRON1 of T. gondii and PfASP of P. falciparum has been reported. METHODS: Subcellular fractionation of sporozoites was performed to obtain highly purified organelles. One-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by liquid chromatography coupled with mass spectrometry was applied for fraction analysis, and 22 potential novel rhoptry proteins were detected by protein domain analysis using online softwares. RESULTS: Twenty-two potential novel rhoptry proteins were detected. A protein with T. gondii and N. caninum rhoptry protein homologs and some proteins with domains similar to that of T. gondii rhoptry proteins were identified. CONCLUSION: These novel candidate proteins may be considered targets for researching the invasion pathway of C. parvum and the pathogenic mechanisms of rhoptry proteins. The present work provides a starting point towards the elucidation of the repertoire and function of C. parvum rhoptry proteins.

11.
Bioorg Med Chem Lett ; 25(12): 2540-4, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25959813

RESUMO

A series of novel matrine-1H-1,2,3-triazole-chalcone conjugates was synthesized and their anticancer activity against A549, Bel-7402, Hela, and MCF-7 cancer cells was evaluated. Most of the conjugates displayed higher potency than their components. Compounds 6h and 6i exhibited more potent anticancer activity than 5-fluorouracil against the four tested human cancer cell lines and lower cytotoxicity to NIH3T3 normal cells. Flow cytometry tests demonstrated that compound 6h could induce apoptosis of A549 cells in a concentration-dependent manner. Moreover, 6h could efficiently suppress human tumor growth in mouse xenograft model without causing obvious toxicities.


Assuntos
Antineoplásicos/síntese química , Chalcona/química , Desenho de Drogas , Alcaloides/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/farmacologia , Células HeLa , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células NIH 3T3 , Quinolizinas/química , Relação Estrutura-Atividade , Transplante Heterólogo , Triazóis/química
12.
Brain Inj ; 29(3): 396-402, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25671811

RESUMO

OBJECTIVE: To investigate whether electro-acupuncture can serve as a method of inducing brain ischaemic tolerance (BIT) by encouraging the expression of glutamate transporter-1 (GLT-1) and suppressing the release of glutamate (Glu). METHODS: Sprague-Dawley (SD) rats were divided into sham, ischaemia and EA groups. EA was performed on dazhui and baihui acupoints and the rat cerebral ischaemia model was achieved by occluding the middle cerebral artery (MCA) for 2 hours, followed by reperfusion. Dialysate was collected from the striatum in vivo to detect the concentration of Glu and the expression of Glutamate Transporter-1 (GLT-1) was examined. The changes of neurological deficit scores were evaluated at 24 hours after reperfusion, while the infarct volumes of brains were then measured with 2,3,5-triphenyltetrazolium chloride (TTC) staining. RESULTS: Compared with the ischaemia group, the concentration of Glu decreased and the expression of GLT-1 increased at most of the detective time points in the EA group; the neurological deficit scores were lower and the infarct volumes were smaller in the EA group. CONCLUSION: EA can up-regulate the expression of GLT-1 and inhibit the excessive release of Glu in the striatum in the process of subsequent ischaemic-reperfusion brain injury, which may be one of the mechanisms of inducing BIT and, thus, be neuroprotective for early ischaemic brain injury.


Assuntos
Terapia por Acupuntura/métodos , Isquemia Encefálica/patologia , Eletroacupuntura , Transportador 2 de Aminoácido Excitatório/metabolismo , Glutamatos/metabolismo , Animais , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley , Regulação para Cima
13.
Zhong Yao Cai ; 38(6): 1230-6, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26762065

RESUMO

OBJECTIVE: To explore the cardioprotective effect and its mechanism of total saponins of Panacis Majoris Rhizoma in myocardial infarction (MI) rats. METHODS: The MI model rats induced by ligating anterior descending branch of coronary artery were randomly divided into four group:model group, total saponins of Panacis Majoris Rhizoma (100 and 200 mg/kg) groups and compound Danshen dripping pills group. The rats were orally administrated with drugs once a day for four weeks. Another rats were selected as sham operation group. After four weeks intervention, cardiac function was examined, the serum levels of TNF-α, IL-1ß, IL-6 and IL-8 were measured by using ELISA, respectively. The myocardial hypertrophy index was investigated, the myocardial infarct size, degree of ventricular dilatation, myocardial interstitial collagen volume fraction and tissue morphology were investigated by HE, Masson, picric acid-sirius red staining and observing with alight microscope and electron microscope. Protein expressions of phosphorylation IκB-α( pIκB-α) and NF-κB p65 in heart tissue were detected by Western blotting. RESULTS: Total saponins of Panacis Majoris Rhizoma might significantly decrease the levels of serum TNF-α, IL-1ß, IL-6 and IL-8; decrease myocardial hypertrophy indexes, myocardial infarct size, degree of ventricular dilatation and myocardial interstitial collagen volume fraction; improve heart tissue morphology and cardiac function; downregulate protein expression of pIκB-α and NF-κBp65; and upregulate protein expression of SIRT1. The aforementioned action effects of total saponins of Panacis Majoris Rhizoma (200 mg/kg) were similar with compound Danshen dripping pills. CONCLUSION: Total saponins of Panacis Majoris Rhizoma possesses cardioprotective effect against ligating left anterior descending branch induced MI in rats. The mechanism may be related to strengthening SIRT1 expression, inhibiting the phosphorylation of IκB-α, and finally inhibiting the activation of NF-κB and proinflammatory production.


Assuntos
Cardiotônicos/química , Infarto do Miocárdio/tratamento farmacológico , Panax/química , Saponinas/química , Animais , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Coração/efeitos dos fármacos , Proteínas I-kappa B/metabolismo , Interleucina-1beta/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Miocárdio/patologia , Inibidor de NF-kappaB alfa , NF-kappa B , Ratos , Rizoma/química , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/sangue
14.
J Stroke Cerebrovasc Dis ; 23(6): 1696-702, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24774439

RESUMO

Stroke is an acute cerebrovascular disease with high incidence, morbidity, and mortality. Preischemic treadmill training has been shown to be effective in improving behavioral and neuropathologic indices after cerebral ischemia. However, the exact neuroprotective mechanism of preischemic treadmill training against ischemic injury has not been elucidated clearly. The present study investigated whether preischemic treadmill training could protect the brain from ischemic injury via regulating cerebral blood flow (CBF) and endothelin 1 (ET-1). We analyzed the CBF by laser speckle imaging and ET-1 expression by an enzyme-linked immunosorbent assay using an ischemic rat model with preischemic treadmill training. Generally speaking, ET-1 expression decreased and CBF increased significantly in the pretreadmill group. It is worth noting that ET-1 expression is increased at 24 hours of reperfusion in the pretreadmill group compared with the level of the time after middle cerebral artery occlusion. These changes were followed by significant changes in neurologic deficits and cerebral infarct volume. This study indicated that preconditioning exercise protected brain from ischemic injury through the improvement of CBF and regulation of ET-1 expression, which may be a novel component of the neuroprotective mechanism of preischemic treadmill training against brain injury.


Assuntos
Isquemia Encefálica/fisiopatologia , Circulação Cerebrovascular/fisiologia , Endotelina-1/metabolismo , Precondicionamento Isquêmico/métodos , Condicionamento Físico Animal/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
15.
Int J Mol Sci ; 15(3): 4453-63, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24633199

RESUMO

Exercise training is a neuroprotective strategy in cerebral ischemic injury, but the underlying mechanisms are not yet clear. In the present study, we investigated the effects of treadmill exercise pretreatment on the expression of mitochondrial dynamic proteins. We examined the expression of OPA1/DLP1/MFF/Mfn1/Mfn2, which regulates mitochondrial fusion and fission, and cytochrome C oxidase subunits (COX subunits), which regulate mitochondrial functions, after middle cerebral artery occlusion (MCAO) in rats. T2-weighted magnetic resonance imaging (MRI) was evaluated as indices of brain edema after ischemia as well. Treadmill training pretreatment increased the expression levels of OPA1 and COXII/III/IV and alleviated brain edema, indicating that exercise pretreatment provided neuroprotection in cerebral ischemic injury via the regulation of mitochondrial dynamics and functions.


Assuntos
Isquemia Encefálica/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas Mitocondriais/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Western Blotting , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Dinaminas/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/fisiopatologia , Imagem por Ressonância Magnética , Masculino , Proteínas de Membrana/metabolismo , Dinâmica Mitocondrial/fisiologia , Ratos Sprague-Dawley , Fatores de Tempo
16.
PLoS One ; 9(1): e84602, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24416250

RESUMO

OBJECTIVE: Treadmill pre-training can ameliorate blood brain barrier (BBB) dysfunction in ischemia-reperfusion injury, however, its role in ischemic brain edema remains unclear. This study assessed the neuroprotective effects induced by treadmill pre-training, particularly on brain edema in transient middle cerebral artery occluded model. METHODS: Transient middle cerebral artery occlusion to induce stroke was performed on rats after 2 weeks of treadmill pre-training. Magnetic resonance imaging (MRI) was used to evaluate the dynamic impairment of cerebral edema after ischemia-reperfusion injury. In addition, measurements of wet and dry brain weight, Evans Blue assay and Garcia scores were performed to investigate the cerebral water content, BBB permeability and neurologic deficit, respectively. Moreover, during ischemia-reperfusion injury, the expression of Aquaporin 4 (AQP4) was detected using immunofluorescence and Western bloting analyses. RESULTS: Treadmill pre-training improved the relative apparent diffusion coefficient (rADC) loss in the ipsilateral cortex and striatum at 1 hour and 2.5 hours after cerebral ischemia. In the treadmill pre-training group, T2W1 values of the ipsilateral cortex and striatum increased less at 7.5 hours, 1 day, and 2 days after stroke while the brain water content decreased at 2 days after ischemia. Regarding the BBB permeability, the semi-quantitative amount of contrast agent leakage of treadmill pre-training group significantly decreased. Less Evans Blue exudation was also observed in treadmill pre-training group at 2 days after stroke. In addition, treadmill pre-training mitigated the Garcia score deficits at 2 days after stroke. Immunofluorescence staining and Western blotting results showed a significant decrease in the expression of AQP4 after treadmill ischemia following pre-training. CONCLUSIONS: Treadmill pre-training may reduce cerebral edema and BBB dysfunction during cerebral ischemia/reperfusion injury via the down-regulation of AQP4.


Assuntos
Aquaporina 4/metabolismo , Edema Encefálico/terapia , Regulação para Baixo , Infarto da Artéria Cerebral Média/complicações , Imagem por Ressonância Magnética , Condicionamento Físico Animal , Acidente Vascular Cerebral/complicações , Animais , Barreira Hematoencefálica/metabolismo , Edema Encefálico/complicações , Edema Encefálico/metabolismo , Permeabilidade , Ratos
17.
Brain Res ; 1533: 114-21, 2013 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-23948104

RESUMO

This study examined whether very early initiated physical rehabilitation (VEIPR), as a recommended therapy for postischemia, could improve motor performance and cerebral blood flow (CBF). Adult male rats with ischemic injury caused by middle cerebral artery occlusion (MCAO) were trained to run on a treadmill for 30min per day at 12m/min. Through such exercise training for 3 days, the ischemic rats exhibited increased motor function and decreased infarct volume, as measured by a behavioral score and 2,3,5-triphenyltetrazolium chloride (TTC) staining method, as well as accelerated CBF, as detected with laser speckle imaging (LSI). Furthermore, to determine whether the observed improved CBF provided the protective factor for motor function recovery, we investigated the apoptosis of ischemic rat brain microvascular endothelial cells (rBMECs), which accepted the mechanical force of CBF directly, under flow intervention. The findings indicated that a modest flow decreased cell apoptosis in the ischemic condition and that this effect is magnitude dependent, as excessive flow increased apoptosis.


Assuntos
Isquemia Encefálica/terapia , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Terapia por Exercício , Animais , Apoptose , Células Endoteliais/patologia , Hemodinâmica , Masculino , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Resultado do Tratamento
18.
PLoS One ; 8(12): e84439, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24391954

RESUMO

BACKGROUND: Type III secretion systems (T3SSs) are central to the pathogenesis and specifically deliver their secreted substrates (type III secreted proteins, T3SPs) into host cells. Since T3SPs play a crucial role in pathogen-host interactions, identifying them is crucial to our understanding of the pathogenic mechanisms of T3SSs. This study reports a novel and effective method for identifying the distinctive residues which are conserved different from other SPs for T3SPs prediction. Moreover, the importance of several sequence features was evaluated and further, a promising prediction model was constructed. RESULTS: Based on the conservation profiles constructed by a position-specific scoring matrix (PSSM), 52 distinctive residues were identified. To our knowledge, this is the first attempt to identify the distinct residues of T3SPs. Of the 52 distinct residues, the first 30 amino acid residues are all included, which is consistent with previous studies reporting that the secretion signal generally occurs within the first 30 residue positions. However, the remaining 22 positions span residues 30-100 were also proven by our method to contain important signal information for T3SP secretion because the translocation of many effectors also depends on the chaperone-binding residues that follow the secretion signal. For further feature optimisation and compression, permutation importance analysis was conducted to select 62 optimal sequence features. A prediction model across 16 species was developed using random forest to classify T3SPs and non-T3 SPs, with high receiver operating curve of 0.93 in the 10-fold cross validation and an accuracy of 94.29% for the test set. Moreover, when performing on a common independent dataset, the results demonstrate that our method outperforms all the others published to date. Finally, the novel, experimentally confirmed T3 effectors were used to further demonstrate the model's correct application. The model and all data used in this paper are freely available at http://cic.scu.edu.cn/bioinformatics/T3SPs.zip.


Assuntos
Proteínas de Bactérias/genética , Sistemas de Secreção Bacterianos/genética , Bactérias Gram-Negativas/metabolismo , Interações Hospedeiro-Patógeno/genética , Modelos Genéticos , Sequência de Aminoácidos/genética , Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos/fisiologia , Sequência Conservada/genética , Interações Hospedeiro-Patógeno/fisiologia , Funções Verossimilhança , Análise em Microsséries , Curva ROC , Especificidade da Espécie
19.
Int J Mol Sci ; 13(8): 9447-59, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22949807

RESUMO

Pre-ischemic treadmill training exerts cerebral protection in the prevention of cerebral ischemia by alleviating neurotoxicity induced by excessive glutamate release following ischemic stroke. However, the underlying mechanism of this process remains unclear. Cerebral ischemia-reperfusion injury was observed in a rat model after 2 weeks of pre-ischemic treadmill training. Cerebrospinal fluid was collected using the microdialysis sampling method, and the concentration of glutamate was determined every 40 min from the beginning of ischemia to 4 h after reperfusion with high-performance liquid chromatography (HPLC)-fluorescence detection. At 3, 12, 24, and 48 h after ischemia, the expression of the glutamate transporter-1 (GLT-1) protein in brain tissues was determined by Western blot respectively. The effect of pre-ischemic treadmill training on glutamate concentration and GLT-1 expression after cerebral ischemia in rats along with changes in neurobehavioral score and cerebral infarct volume after 24 h ischemia yields critical information necessary to understand the protection mechanism exhibited by pre-ischemic treadmill training. The results demonstrated that pre-ischemic treadmill training up-regulates GLT-1 expression, decreases extracellular glutamate concentration, reduces cerebral infarct volume, and improves neurobehavioral score. Pre-ischemic treadmill training is likely to induce neuroprotection after cerebral ischemia by regulating GLT-1 expression, which results in re-uptake of excessive glutamate.


Assuntos
Lesões Encefálicas/prevenção & controle , Isquemia Encefálica/prevenção & controle , Transportador 2 de Aminoácido Excitatório/metabolismo , Terapia por Exercício/métodos , Glutamatos/metabolismo , Infarto da Artéria Cerebral Média/prevenção & controle , Fármacos Neuroprotetores , Animais , Western Blotting , Lesões Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Terapia por Exercício/instrumentação , Infarto da Artéria Cerebral Média/metabolismo , Masculino , Microdiálise , Ratos , Ratos Sprague-Dawley
20.
Wei Sheng Yan Jiu ; 40(6): 720-2, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22279664

RESUMO

OBJECTIVE: To measure the energy expenditure of healthy adults engaged in light activities in southern China, and to provide reference database for revising Chinese RNI. METHODS: Thirty four healthy adults eligible for the energy metabolic experiment were selected. A 3-day recycled dietary prescription was designed. The food intake of all foods per person per meal were weighed and recorded, and the energy intake from diets was determined by chemical analysis. The energy expenditure was calculated by combining the change of body weight and dietary consumption. RESULTS: The average energy intake was (8424 +/- 1616) kJ/d [(2013 +/- 386) kcal/d], which was (9990 +/- 798) kJ/d [(2388 +/- 191) kcal/d] for men and (7032 +/- 384)kJ/d [(1681 +/- 92) kcal/d] for women. The average change of body weight of all subjects in 16 days was reduced 0.02 kg, the men increased 0.15 kg, and the women decreased 0.17 kg. According to the energy balance principle, the ultimate energy expenditure of healthy adults in southern China was (8468 +/- 1762) kJ/d [(2024 +/- 421) kcal/d], the men was (9680 +/- 1759) kJ/d [(2314 +/- 420) kcal/d], and the women was (7391 +/- 827) kJ/d [(1767 +/- 198) kcal/d]. CONCLUSIONS: The energy expenditure of healthy adult male engaged in light activities in southern China was 9680 +/- 1759 kJ/d [(2314 +/- 420 kcal/d)], and that of female was 7391 +/- 827 kJ/d [(1767 +/- 198 kcal/d)]. The energy expenditure of men and women measured in this study were 86kcal and 333kcal lower than the Chinese energy RNI (2400kcal and 2100 kcal) established in 2000.


Assuntos
Metabolismo Basal/fisiologia , Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Alimentos/normas , Adolescente , Adulto , Peso Corporal , China , Inquéritos sobre Dietas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Adulto Jovem
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