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1.
ChemSusChem ; 17(6): e202301634, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37994392

RESUMO

Efficient electrochemical CO2 reduction reaction (ECO2RR) to multi-electron reductive products remains a great challenge. Herein, molecular engineering of copper phthalocyanines (CuPc) was explored by modifying electron-withdrawing groups (EWGs) (cyano, sulfonate anion) and electron-donating groups (EDGs) (methoxy, amino) to CuPc, then supporting onto carbon paper or carbon cloth by means of droplet coating, loading with carbon nanotubes and coating in polypyrrole (PPy). The results showed that the PPy-coated CuPc effectively catalysed ECO2RR to CH4. Interestingly, experimental results and DFT calculations indicated EWGs markedly improved the selectivity of methane for the reason that the introduction of EWGs reduces electron density of catalytic active center, resulting in a positive move to initial reduction potential. Otherwise, the modification of EDGs significantly reduces the selectivity towards methane. This electronic effect and heterogenization of CuPc are facile and effective molecular engineering, benefitting the preparation of electrocatalysts for further reduction of CO2.

2.
ChemSusChem ; 15(23): e202201455, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36163546

RESUMO

Immobilizing cobalt phthalocyanine (CoPc) onto the electrode surface is a significant approach to performing efficient electrochemical CO2 reduction reaction (ECO2 RR). Herein, sulfylphenoxy decorated CoPc cross-linked polypyrrole is prepared by in situ polymerization on the surface of carbon cloth. The synthesized N-rich catalyst exhibits above 95 % Faradaic efficiency toward CO (FECO ) at -0.9 V versus reversible hydrogen electrode (RHE) at least for 10 h in aqueous solution and even enables direct electrolysis at low CO2 concentrations, being potential for coupling ECO2 RR with CO2 capture. This facile in situ polymerization strategy would pave the way for developing efficient and practical electrocatalysis for ECO2 RR.


Assuntos
Polímeros , Pirróis , Dióxido de Carbono , Indóis
3.
Angew Chem Int Ed Engl ; 61(44): e202205301, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-35866885

RESUMO

The electrocatalytic CO2 reduction reaction (ECO2 RR) is one promising method for storing intermittent clean energy in chemical bonds and producing fuels. Among various kinds of catalysts for ECO2 RR, molecular metal complexes with well-defined structures are convenient for studies of their rational design, structure-reactivity relationships, and mechanisms. In this Review, we summarize the molecular engineering of several N-based metal complexes including Re/Mn bipyridine compounds and metal macrocycles, concluding with general modification strategies to devise novel molecular catalysts with high intrinsic activity. Through physical adsorption, covalent linking, and formation of a periodic backbone, these active molecules can be heterogenized into immobilized catalysts with more practical prospects. Finally, significant challenges and opportunities based on molecular catalysts are discussed.

4.
Angew Chem Int Ed Engl ; 61(27): e202200751, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35441773

RESUMO

A triblock amphiphilic polymer derived from the copolymerization of CO2 and epoxides containing a bipyridine rhenium complex in its backbone is shown to effectively catalyze the visible-light-driven reduction of CO2 to CO. This polymer provides uniformly spherical micelles in aqueous solution, where the metal catalyst is sequestered in the hydrophobic portion of the nanostructured micelle. CO2 to CO reduction occurs in an efficient visible-light-driven process in aqueous media with turnover numbers up to 110 (>99 % selectivity) in the absence of a photosensitizer, which is a 37-fold enhancement over the corresponding molecular rhenium catalyst in organic solvent. Notably, the amphiphilic polycarbonate micelle rhenium catalyst suppresses H2 generation, presumably by preventing deactivation of the active catalytic center by water.

5.
Kaohsiung J Med Sci ; 38(5): 457-468, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34962345

RESUMO

Aging is characterized by inevitable organ function decline over time, with consequent body deterioration and increased susceptibility to death. Astragalus polysaccharide (APS) has been reported to have anti-oxidative, anti-apoptotic, and anti-inflammatory properties. We investigated the potential protective effects of APS on hydrogen peroxide (H2 O2 ) induced hepatocyte senescence and identified related mechanisms in L02, Huh7, and LM3 cell lines. Aged female C57BL/6 mice were given APS for 1 week by intraperitoneal injection, and APS provided the strongest protective effect against H2 O2 -induced damage at 100 µM. APS reduced the expression of cell senescence markers and alleviated pathological damage in aged mouse liver. APS treatment decreased oxidative stress, apoptosis, NOD-like receptor protein-3-mediated pyroptosis, and maintained mitochondrial homeostasis. Notably, the protective effect of APS was weakened in the presence of chloroquine. APS might enrich autophagy by activating AMP-activated protein kinase (AMPK) and inhibiting mammalian target of rapamycin (mTOR). In conclusion, APS reduced reactive oxygen species levels, inhibited apoptosis and pyroptosis, and promoted mitophagy via AMPK/mTOR pathway to alleviate hepatocyte senescence in vitro and in vivo.


Assuntos
Proteínas Quinases Ativadas por AMP , Astrágalo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose , Astrágalo/metabolismo , Autofagia , Hepatócitos/metabolismo , Mamíferos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Polissacarídeos/farmacologia , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(5): 743-748, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34728035

RESUMO

Objective To evaluate the effects of antiretroviral therapy(ART)for the prevention of mother-to-child transmission(PMTCT)of acquired immune deficiency syndrome(AIDS)on the growth and development of 18-month-old children born by human immunodeficiency virus(HIV)-positive pregnant women in Lingshan County,Guangxi Zhuang Autonomous Region,and provide scientific evidence for improving the ART medication plan for PMTCT.Methods Lingshan County,ranking the first in the HIV-epidemic counties of Guangxi,was selected as the research site.According to the design of retrospective case-control study,we assigned all the subjects into the case group and the control group:(1)The case group included the HIV-positive pregnant women who had received ART for PMTCT and their HIV-negative infants in Lingshan County from 2010 to 2017.The historical cards and PMTCT data of them were collected from the national PMTCT database.(2)The control group included the healthy pregnant women and their healthy babies born in the Lingshan Maternity and Infant Hospital in 2017,and the children's growth and development data were collected.The stunted growth in children was defined as at least one of the three main indicators of body height,body weight,and head circumference below the normal range.Results The number of HIV-positive mothers and their infants in the case group was 391 and 368,respectively,and 87.21%(341/391)and 95.38%(351/368)of mothers and infants respectively received ART medication.The HIV positive rate,mortality rate,and mother-to-child transmission rate of 18-month-old children were 1.36%(5/368),4.35%(16/368),and 2.01%(5/249),respectively.The incidence of stunted growth of 18-month-old children in the case group and the control group was 42.12%(155/368)and 23.06%(101/438),respectively,with significant difference(χ2=33.520,P<0.001).Conclusion After HIV-positive mothers in Lingshan County of Guangxi received ART for PMTCT,the incidence of growth stunting in 18-month-old children increased.


Assuntos
Infecções por HIV , Complicações Infecciosas na Gravidez , Estudos de Casos e Controles , China/epidemiologia , Feminino , Crescimento e Desenvolvimento , HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mães , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Estudos Retrospectivos
7.
ACS Biomater Sci Eng ; 6(1): 664-672, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33463219

RESUMO

Local resection or ablation remains an important approach to treat drug-resistant central neurological disease. Conventional surgical approaches are designed to resect the diseased tissues. The emergence of photothermal therapy (PTT) offers a minimally invasive alternative. However, their poor penetration and potential off-target effect limit their clinical application. Here, polydopamine nanoparticles (PDA-NPs) were prepared and characterized. Studies were performed to evaluate whether PDA-NPs combined with near-infrared (NIR) light can be used to ablate deep brain structures in vitro and in vivo. PDA-NPs were prepared with a mean diameter of ∼150 nm. The particles show excellent photothermal conversion efficiency. PDA-NPs did not show remarkable cytotoxicity against neuronal-like SH-SY5Y cell lines. However, it can cause significant cell death when combined with NIR irradiation. Transcranial NIR irradiation after PDA-NPs administration induced enhanced local hyperthermia as compared with NIR alone. Local temperature exceeded 60 °C after 6 min of irradiation plus PDA while it can only reach 48 °C with NIR alone. PTT with PDA (10 mg/mL, 3 µL) and NIR (1.5 W/cm2) can ablate deep brain structures precisely with an ablation volume of ∼6.5 mm3. Histological analysis confirmed necrosis and apoptosis in the targeted area. These results demonstrate the potential of NP-assisted PTT for the treatment against nontumorous central neurological diseases.


Assuntos
Nanopartículas , Fototerapia , Encéfalo/cirurgia , Indóis , Polímeros
8.
Cytokine ; 119: 113-118, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30903865

RESUMO

Recent studies have provided overwhelming evidence of the involvement of microglia-related molecular networks in the pathogenesis of Alzheimer's diseases (AD). The potential involvement of pro-inflammatory cytokines interleukin (IL)-18, IL-23 and IL-17 on amyloid (Aß) clearance is still unclear. In this study, we addressed that there might be a net relationship among IL-18, IL-23, and IL-17 and they can affect Aß clearance in cultured macrophage/microglia cells. In human macrophage cell line THP-1, Aß42 incubation could increase the expression of IL-18, IL-23 and IL-17 in a concentration dependent manner. THP-1 cell could clear Aß42 in the culture medium time-dependently, but its capacity of Aß clearance was impaired by IL-18, IL-23 or IL-17 treatment. Similarly, the capacity of the microglia cell line BV2 to clear Aß42 was impaired by IL-18, IL-23 or IL-17 treatment. In co-cultures of BV2 with APP/PS1 neuron, Aß was efficiently cleared by BV2 cell, but Aß clearance was impaired by IL-18, IL-23 or IL-17 treatment. The effects of IL-18, IL-23 and IL-17 could be blocked by their corresponding neutralizing antibodies. In addition, the inhibitory effects of IL-18 were blocked by IL-23 or IL-17 neutralizing antibodies while the inhibitory effects of IL-23 were blocked by IL-17 neutralizing antibodies. Our study provides evidences showing that amyloid induced IL-18/IL-23/IL-17 axis could impair macrophage and microglia-mediated Aß clearance. Thus, IL-18/IL-23/IL-17 axis might be a therapeutic target in AD.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Interleucina-17/metabolismo , Interleucina-18/metabolismo , Subunidade p19 da Interleucina-23/metabolismo , Células THP-1/metabolismo , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Neurônios/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-30684527

RESUMO

BACKGROUND: Transient receptor potential canonical (TRPC) 6 inhibits Aß in Alzheimer's disease (AD) mouse brain and improves the behavioral performance. AIMS: To evaluate the association of TRPC6 expression in peripheral leucocytes from AD and mild cognitive impairment (MCI) patients and to explore its potential value in early diagnosis of AD. METHODS: TRPC6 mRNA levels in peripheral leucocytes were detected by quantitative real-time PCR. The Spearman correlation test was used to ascertain the associations between TRPC6 and the scores of MMSE, ADL, CSDD, CDR. The Receiver Operating Characteristic (ROC) curve was drawn to evaluate the diagnostic potential of TRPC6 for AD and MCI. RESULTS: There were 108 CE, 136 MCI, 164 Con and 60 PD in the study. The expression of TRPC6 mRNA level in peripheral leucocytes was significantly lower: 1) in patients with AD and MCI compared to Con; 2) in AD compared to MCI; 3) in hospitalized AD compared to AD from communities. There was a significantly positive correlation between TRPC6 mRNA and MMSE score (p = .001, R = 0.327). Significantly inverse correlations were found between TRPC6 and CDR score (p < 0.001, R = -0.303) as well as between TRPC6 and ADL score (p = .001, R = -0.342) for all AD. The area under curve of ROC was 0.881 for the classification of AD, and 0.706 for the classification of MCI, respectively. CONCLUSION: TRPC6 expression is inversely correlated with cognitive performance of AD. TRPC6 in peripheral leucocytes may be a potential biomarker for the diagnosis of AD.


Assuntos
Doença de Alzheimer/metabolismo , Disfunção Cognitiva/metabolismo , Canal de Cátion TRPC6/biossíntese , Idoso , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Hospitalização , Humanos , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/metabolismo , Escalas de Graduação Psiquiátrica/estatística & dados numéricos
10.
Brain Behav ; 8(3): e00937, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29541547

RESUMO

Objectives: To investigate the association between neck circumference (NC) and cognitive impairment and interactions between relevant variables to the risk of cognitive impairment. Methods: A population-based survey was conducted among elderly inhabitants aged 60 years and over from a community in Shanghai suburb. Multivariate logistic regression analyses were performed to evaluate associations and log likelihood ratio tests to examine interactions. Results: Cognitive impairment was identified in 269 (10.8%) subjects from 2,500 participants. Higher BMI (OR = 1.55; 95% CI = 1.11-2.16), higher WHR (OR = 1.44; 95% CI = 1.07-1.95), and higher total cholesterol (TC) (OR = 1.52; 95% CI = 1.09-2.13) were significantly associated with the increased risk of cognitive impairment. Significant interactions were observed between TC and a few other relevant variables, respectively. Conclusions: NC was associated with the high risk of cognitive impairment. Additive effects of NC with TC on cognitive impairment were observed.


Assuntos
Disfunção Cognitiva/patologia , Pescoço/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , China/etnologia , Disfunção Cognitiva/etnologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Fatores de Risco
11.
Brain Res Bull ; 137: 301-305, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29325993

RESUMO

BACKGROUND: Serum level of Haptoglobin (Hp) maybe associated with Alzheimer's disease (AD) and mild cognitive impairment (MCI). OBJECTIVE: To investigate associations between serum Hp and AD, as well as between Hp and MCI. METHODS: Serum levels of Hp were measured and analyzed for 51 patients with AD, 139 patients with MCI and their healthy controls matched with sex and age. All study subjects were from a survey among residents aged 60 years and over in a community located in the southwest suburb of Shanghai. RESULTS: Serum levels of Hp were observed significantly higher in AD and MCI cases than controls (both p < 0.0001). A significant positive correlation was found between Hp and Activities of Daily Living (ADL) score (rs = 0.430, p = 0.007), as well as between Hp and Clinical Dementia Rating (CDR) score (rs = 0.359, p = 0.027) in all AD patients. According to the receiver operating characteristic (ROC) curve analysis, the optimal cut-off point for Hp was found to be 67.50 µg/ml (sensitivity, 0.902; specificity, 0.745) in AD patients, and 44.76 µg/ml (sensitivity, 0.986; specificity, 0.403) in MCI patients. CONCLUSION: Elevated serum levels of Hp were observed in AD and MCI patients than controls. In addition, Hp may correlate with the severity of AD.


Assuntos
Doença de Alzheimer/sangue , Disfunção Cognitiva/sangue , Haptoglobinas/metabolismo , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Curva ROC , Índice de Gravidade de Doença
12.
J Alzheimers Dis ; 51(4): 1175-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26923017

RESUMO

BACKGROUND: Metabolic syndrome (MetS) maybe associated with mild cognitive impairment (MCI). OBJECTIVE: To investigate the relationship between MetS, with its individual or combined components, and MCI among elderly. METHODS: A case-control study was conducted among the elderly aged 65 years and over in a community located in the southwestern suburb of Shanghai, China. The Chinese version of the Mini-Mental Status Examination (C-MMSE) was used to screen subjects with MCI. Associations of MetS with its individual or combined components and MCI were analyzed using conditional regression analyses with or without adjustment for gender, education, current smoking, current drinking, and physical activities. RESULTS: There were 379 subjects with MCI and 379 gender- and age-matched healthy controls in the study. Compared with healthy controls in univariate analyses, subjects with MCI were more likely to have less time spent on physical activity, lower C-MMSE score, heavier weight, larger waistline and hipline, higher diastolic blood pressure, higher body mass index, higher abdominal obesity index, higher serum glycated hemoglobin, higher serum triglycerides, higher serum cholesterol, higher serum uric acid, and higher serum alanine aminotransferase. After multivariable adjustment, MetS was significantly associated with an increased risk of MCI (OR = 2.277; 95% CI: 1.086-4.773). Among MetS components, abdominal obesity (OR = 2.101; 95% CI: 1.224-3.608) and hypertension (OR = 2.075; 95% CI: 1.170-3.678) showed a significant association with MCI, respectively; while these two components were combined, the association was stronger (OR = 2.459; 95% CI: 1.360-4.447). CONCLUSION: MetS and its components, particularly abdominal obesity and hypertension, were found to be significantly associated with the risk of MCI.


Assuntos
Envelhecimento , Transtornos Cognitivos/complicações , Transtornos Cognitivos/epidemiologia , Doenças Metabólicas/complicações , Doenças Metabólicas/epidemiologia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , China/epidemiologia , Cidades/epidemiologia , Planejamento em Saúde Comunitária , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Fatores de Risco
13.
Zhong Yao Cai ; 38(6): 1183-5, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26762058

RESUMO

OBJECTIVE: To establish the HPLC fingerprint of Clerodendrum lindleyi in order to provide the basis for its quality standard. METHODS: The chromatographic fingerprint was obtained with Angilent Zorbax C18 (250 mm x 4.6 mm, 5 µm) column and gradiently eluted with acetonitrile-0.1% phosphoric acid solution. The column temperature was maintained at 35 degrees C. The flow rate was 1.0 mL/min and the detection wavelength was 327 nm. RESULTS: HPLC fingerprint of Clerodendrum lindleyi was established and 21 common peaks from 11 batches of samples were found. CONCLUSION: The method has good precision, stability and repeatability, which can provide reliable basis for quality evaluation of Clerodendrum lindleyi.


Assuntos
Cromatografia Líquida de Alta Pressão , Clerodendrum/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/normas , Controle de Qualidade
14.
Dement Geriatr Cogn Disord ; 38(5-6): 321-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25138786

RESUMO

AIMS: To evaluate the serum levels of interleukin (IL)-18, IL-23 and IL-17 in Chinese patients with Alzheimer's disease (AD), and explore correlations between the three cytokines and relevant parameters. METHODS: Serum concentrations of IL-18, IL-23 and IL-17 were measured by ELISA for 53 AD patients and 53 sex- and age-matched healthy controls in a community of elderly individuals in a Shanghai suburb. RESULTS: Serum concentrations of IL-18, IL-23 and IL-17 were significantly higher in AD patients than controls. The serum level of IL-23 was observed to be significantly higher (p = 0.049) in female AD patients than male AD patients. In addition, a significantly inverse correlation was found between IL-18 and MMSE score (rs = -0.356, p = 0.011) for all AD patients. CONCLUSION: Elevated IL-18, IL-23 and IL-17 levels are observed in AD patients and differences may exist between males and females. Besides, IL-18 may correlate with the severity of AD.


Assuntos
Doença de Alzheimer/sangue , Interleucina-17/sangue , Interleucina-18/sangue , Interleucina-23/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Povo Asiático , China , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Fatores Sexuais
15.
PLoS One ; 9(6): e100354, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24945257

RESUMO

Acutobin isolated from Deinagkistrodon acutus venom has been used to prevent or treat stroke in patients. This defibrinogenating serine protease is a 39 kDa glycoprotein containing terminal disialyl-capped N-glycans. After sialidase treatment, the enzyme showed similar catalytic activities toward chromogenic substrate, and cleaved the Aα chain of fibrinogen as efficiently as the native acutobin did. However, the level of fibrinogen degradation products in mice after i.p.-injection of desialylated-acutobin was significantly lower than the level after acutobin injection, suggesting that the disialyl moieties may improve or prolong the half-life of acutobin. Two recombinant enzymes with identical protein structures and similar amidolytic activities to those of native acutobin were expressed from HEK293T and SW1353 cells and designated as HKATB and SWATB, respectively. Mass spectrometric profiling showed that their glycans differed from those of acutobin. In contrast to acutobin, HKATB cleaved not only the Aα chain but also the Bß and γ chains of human fibrinogens, while SWATB showed a reduced α-fibrinogenase activity. Non-denaturing deglycosylation of these proteases by peptide N-glycosidase F significantly reduced their fibrinogenolytic activities and thermal stabilities. The in vivo defibrinogenating effect of HKATB was inferior to that of acutobin in mice. Taken together, our results suggest that the conjugated glycans of acutobin are involved in its interaction with fibrinogen, and that the selection of cells optimally expressing efficient glycoforms and further glycosylation engineering are desirable before a recombinant product can replace the native enzyme for clinical use.


Assuntos
Venenos de Crotalídeos/farmacologia , Fibrinolíticos/farmacologia , Polissacarídeos/metabolismo , Proteínas Recombinantes/farmacologia , Trombina/farmacologia , Animais , Biocatálise/efeitos dos fármacos , Células CHO , Cricetinae , Cricetulus , Venenos de Crotalídeos/química , Venenos de Crotalídeos/isolamento & purificação , Estabilidade Enzimática/efeitos dos fármacos , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinólise/efeitos dos fármacos , Glicosilação/efeitos dos fármacos , Células HEK293 , Humanos , Hidrólise , Cinética , Camundongos , Peso Molecular , Mapeamento de Peptídeos , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Peptídeos/química , Polissacarídeos/química , Isoformas de Proteínas/química , Isoformas de Proteínas/farmacologia , Coelhos , Soroglobulinas/metabolismo , Especificidade por Substrato/efeitos dos fármacos , Trombina/química , Trombina/isolamento & purificação
16.
Am J Alzheimers Dis Other Demen ; 29(8): 712-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24928820

RESUMO

OBJECTIVES: To investigate the association between serum C-reactive protein (CRP) concentration and cognitive impairment as well as interactions between CRP and other relevant factors. METHODS: Patients with cognitive impairment and 1 to 2 age- and sex-matched controls nested from a population-based study among residents aged 60 years and older in Shanghai suburb. The associations of serum CRP concentration and other relevant factors were examined with logistic regression analysis. RESULTS: The mean CRP in patients with cognitive impairment was higher than that in controls (P < .001). The highest quartile of CRP (>4.77 mg/L), abdomen obesity, hypertriglyceridemia, and hyperglycemia was associated with cognitive impairment. Significant interactions were found between increased CRP and hypertriglyceridemia as well as between increased CRP and hyperglycemia on cognitive impairment; and the attributable proportion due to interaction was 82% (P < .0001) and 37% (P = .007), respectively. CONCLUSIONS: Increased CRP was associated with cognitive impairment, and additive effects of increased CRP with hypertriglyceridemia and hyperglycemia on cognitive impairment were observed among elderly individuals.


Assuntos
Glicemia/metabolismo , Proteína C-Reativa/metabolismo , Transtornos Cognitivos/metabolismo , Hiperglicemia/metabolismo , Hipertrigliceridemia/metabolismo , Triglicerídeos/metabolismo , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/epidemiologia , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Transtornos Cognitivos/epidemiologia , Feminino , Humanos , Hiperglicemia/epidemiologia , Hipertrigliceridemia/epidemiologia , Insulina/metabolismo , Resistência à Insulina , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Fatores de Risco , População Suburbana/estatística & dados numéricos
17.
Mol Med Rep ; 8(5): 1337-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24002180

RESUMO

Mossy fiber sprouting (MFS) is a pathological phenomenon that is commonly observed in temporal lobe epilepsy (TLE). However, the molecular mechanisms underlying MFS remain unclear. It has been demonstrated that the tau protein is important in the progression of MFS by the regulation of microtubule dynamics and axonal transport, with all of these functions of tau modulated by its site-specific phosphorylation. Glycogen synthase kinase-3ß (GSK-3ß) is an active kinase that regulates the phosphorylation of tau protein. Therefore, it was hypothesized that GSK-3ß contributes to MFS by phosphorylating tau protein. The aim of the present study was to determine the expression and activity of GSK-3ß at different regions in the rat hippocampus during the pentylenetetrazole (PTZ)-kindling process in order to demonstrate the possible correlation with MFS, and to investigate the involvement of GSK-3ß in epileptogenesis. Male Sprague-Dawley rats (n=180) were randomly divided into the control and PTZ-treated groups. The chronic epileptic model was established by intraperitoneal injection of PTZ and the hippocampus was observed for the presence of MFS using Timm staining. GSK-3ß mRNA, protein and activity were analyzed in various regions of the hippocampus using in situ hybridization, immunohistochemistry and immunoprecipitation followed by a kinase assay and liquid scintillation counting, respectively. MFS was observed prior to kindling and an increased distribution of Timm granules were observed in the CA3 region of the PTZ-treated rats; however, this was not demonstrated in the supragranular layer of the dentate gyrus. The expression of GSK-3ß mRNA and protein, as well as the GSK-3ß activity, increased significantly from 3 days to 4 weeks in the PTZ group, and this was correlated with the progression of MFS in the CA3 area. In addition, it was demonstrated that MFS did not result from TLE. GSK-3ß may therefore be involved in the progression of MFS and is important in epileptogenesis. An understanding of the molecular mechanisms underlying MFS may lead to the identification of a novel therapeutic target to limit epileptogenesis.


Assuntos
Convulsivantes/toxicidade , Modelos Animais de Doenças , Quinase 3 da Glicogênio Sintase/metabolismo , Excitação Neurológica/patologia , Fibras Musgosas Hipocampais/patologia , Pentilenotetrazol/toxicidade , Convulsões/patologia , Animais , Comportamento Animal , Glicogênio Sintase Quinase 3 beta , Técnicas Imunoenzimáticas , Hibridização In Situ , Excitação Neurológica/efeitos dos fármacos , Excitação Neurológica/metabolismo , Masculino , Fibras Musgosas Hipocampais/efeitos dos fármacos , Fibras Musgosas Hipocampais/metabolismo , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/metabolismo
18.
FEBS J ; 279(15): 2672-82, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22630045

RESUMO

Most of the phospholipases A(2) (PLA(2) ; EC3.1.1.4) variants isolated so far from snake venoms are nonglycosylated enzymes. In the present study, we purified an active glycosylated PLA(2) and an inactive nonglycosylated Lys49-like PLA(2) from two geographical venom samples of Tropidolaemus. The PLA(2) variants from the two samples have rather different N-terminal sequences, implying that the samples were probably derived from two species (Tropidolaemus subannulatus and Tropidolaemus wagleri). The active PLA(2) s from Sulawesi and Sumatra venoms were designated as Tsu-E6 and Twa-E6, respectively, as a result of the presence of their conserved Glu6 residue. Tsu-E6 inhibited ADP-induced aggregation of mouse and human platelets. Twa-E6 stimulated the aggregation of mouse platelets but inhibited the aggregation of human platelets. Both PLA(2) s were found to be glycosylated at Asn14. Using MALDI-TOF analysis, the released glycans were shown to comprise complex type oligosaccharides without sialylation. This is the first glycan structure of the snake venom PLA(2) to be solved. Furthermore, the enzymatic removal of glycans from both PLA(2) s did not significantly alter their effects on lipid hydrolysis and platelet aggregation. The thermostability of glycosylated Twa-E6 was also found to be as good as that of other homologous PLA(2) s. The presence of these oligosaccharides in PLA(2) s warrants further analyses, which may provide useful insights into the functional regulation of these biomolecules.


Assuntos
Venenos de Crotalídeos/química , Venenos de Crotalídeos/enzimologia , Adulto , Sequência de Aminoácidos , Animais , Varredura Diferencial de Calorimetria , Venenos de Crotalídeos/genética , Venenos de Crotalídeos/toxicidade , Estabilidade Enzimática , Variação Genética , Glicosilação , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Peso Molecular , Agregação Plaquetária/efeitos dos fármacos , Polissacarídeos/química , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Viperidae/genética , Viperidae/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-22259437

RESUMO

The title compound, C(12)H(18)N(8) (2+)·2NO(3) (-)·2H(2)O, was synthesized unexpectedly from 3-amino-1-methyl-1,4,5,6-tetra-hydro-pyrrolo-[3,4-c]pyrazol-5-ium chloride and cerium(IV) ammonium nitrate. The cation has a crystallographically imposed centre of symmetry. In the crystal, the ions and water mol-ecules are linked via O-H⋯N, N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network.

20.
Stem Cells ; 29(12): 1995-2004, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21956927

RESUMO

Glycosphingolipids (GSLs) are ubiquitous components of cell membranes that can act as mediators of cell adhesion and signal transduction and can possibly be used as cell type-specific markers. Our previous study indicated that there was a striking switch in the core structures of GSLs during differentiation of human embryonic stem cells (hESCs) into embryoid body (EB), suggesting a close association of GSLs with cell differentiation. In this study, to further clarify if alterations in GSL patterns are correlated with lineage-specific differentiation of hESCs, we analyzed changes in GSLs as hESCs were differentiated into neural progenitors or endodermal cells by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and tandem mass spectrometry (MS/MS) analyses. During hESC differentiation into neural progenitor cells, we found that the core structures of GSLs switched from globo- and lacto- to mostly ganglio-series dominated by GD3. On the other hand, when hESCs were differentiated into endodermal cells, patterns of GSLs totally differed from those observed in EB outgrowth and neural progenitors. The most prominent GSL identified by the MALDI-MS and MS/MS analysis was Gb(4) Ceramide, with no appreciable amount of stage-specific embryonic antigens 3 or 4, or GD3, in endodermal cells. These changes in GSL profiling were accompanied by alterations in the biosynthetic pathways of expressions of key glycosyltransferases. Our findings suggest that changes in GSLs are closely associated with lineage specificity and differentiation of hESCs.


Assuntos
Diferenciação Celular , Ectoderma/citologia , Células-Tronco Embrionárias/citologia , Endoderma/citologia , Glicoesfingolipídeos/metabolismo , Linhagem da Célula , Ectoderma/metabolismo , Células-Tronco Embrionárias/metabolismo , Endoderma/metabolismo , Citometria de Fluxo , Imunofluorescência , Gangliosídeos/metabolismo , Globosídeos/metabolismo , Glicosiltransferases/metabolismo , Humanos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
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