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1.
Proc Natl Acad Sci U S A ; 121(6): e2318174121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289955

RESUMO

Atomically dispersed catalysts are a promising alternative to platinum group metal catalysts for catalyzing the oxygen reduction reaction (ORR), while limited durability during the electrocatalytic process severely restricts their practical application. Here, we report an atomically dispersed Co-doped carbon-nitrogen bilayer catalyst with unique dual-axial Co-C bonds (denoted as Co/DACN) by a smart phenyl-carbon-induced strategy, realizing highly efficient electrocatalytic ORR in both alkaline and acidic media. The corresponding half-wave potential for ORR is up to 0.85 and 0.77 V (vs. reversible hydrogen electrode (RHE)) in 0.5 M H2SO4 and 0.1 M KOH, respectively, representing the best ORR activity among all non-noble metal catalysts reported to date. Impressively, the Zn-air battery (ZAB) equipped with Co/DACN cathode achieves outstanding durability after 1,688 h operation at 10 mA cm-2 with a high current density (154.2 mA cm-2) and a peak power density (210.1 mW cm-2). Density functional theory calculations reveal that the unique dual-axial cross-linking Co-C bonds of Co/DACN significantly enhance the stability during ORR and also facilitate the 4e- ORR pathway by forming a joint electron pool due to the improved interlayer electron mobility. We believe that axial engineering opens a broad avenue to develop high-performance heterogeneous electrocatalysts for advanced energy conversion and storage.

2.
Lipids Health Dis ; 20(1): 151, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34727932

RESUMO

BACKGROUND: Acylcarnitine is an intermediate product of fatty acid oxidation. It is reported to be closely associated with the occurrence of diabetic cardiomyopathy (DCM). However, the mechanism of acylcarnitine affecting myocardial disorders is yet to be explored. This current research explores the different chain lengths of acylcarnitines as biomarkers for the early diagnosis of DCM and the mechanism of acylcarnitines for the development of DCM in-vitro. METHODS: In a retrospective non-interventional study, 50 simple type 2 diabetes mellitus patients and 50 DCM patients were recruited. Plasma samples from both groups were analyzed by high throughput metabolomics and cluster heat map using mass spectrometry. Principal component analysis was used to compare the changes occurring in the studied 25 acylcarnitines. Multivariable binary logistic regression was used to analyze the odds ratio of each group for factors and the 95% confidence interval in DCM. Myristoylcarnitine (C14) exogenous intervention was given to H9c2 cells to verify the expression of lipid metabolism-related protein, inflammation-related protein expression, apoptosis-related protein expression, and cardiomyocyte hypertrophy and fibrosis-related protein expression. RESULTS: Factor 1 (C14, lauroylcarnitine, tetradecanoyldiacylcarnitine, 3-hydroxyl-tetradecanoylcarnitine, arachidic carnitine, octadecanoylcarnitine, 3-hydroxypalmitoleylcarnitine) and factor 4 (octanoylcarnitine, hexanoylcarnitine, decanoylcarnitine) were positively correlated with the risk of DCM. Exogenous C14 supplementation to cardiomyocytes led to increased lipid deposition in cardiomyocytes along with the obstacles in adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathways and affecting fatty acid oxidation. This further caused myocardial lipotoxicity, ultimately leading to cardiomyocyte hypertrophy, fibrotic remodeling, and increased apoptosis. However, this effect was mitigated by the AMPK agonist acadesine. CONCLUSIONS: The increased plasma levels in medium and long-chain acylcarnitine extracted from factors 1 and 4 are closely related to the risk of DCM, indicating that these factors can be an important tool for DCM risk assessment. C14 supplementation associated lipid accumulation by inhibiting the AMPK/ACC/CPT1 signaling pathway, aggravated myocardial lipotoxicity, increased apoptosis apart from cardiomyocyte hypertrophy and fibrosis were alleviated by the acadesine.


Assuntos
Carnitina/análogos & derivados , Diabetes Mellitus Tipo 2/complicações , Cardiomiopatias Diabéticas/metabolismo , Metabolismo dos Lipídeos , Adulto , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Biomarcadores/sangue , Carnitina/sangue , Carnitina/química , Carnitina/farmacologia , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Mioblastos Cardíacos/efeitos dos fármacos , Mioblastos Cardíacos/metabolismo , Ácidos Mirísticos/farmacologia , Ratos , Estudos Retrospectivos , Ribonucleosídeos/farmacologia , Fatores de Risco
3.
Angew Chem Int Ed Engl ; 60(17): 9546-9552, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33559336

RESUMO

The catalytic conversion of alcohols under mild conditions is a great challenge because it is constrained by low selectivity and low activity. Herein, we demonstrate a hollow nanotube Fe2 O3 /MoO3 heterojunction (FeMo-2) for the photoelectrocatalytic conversion of small-molecule alcohols. Experimental and theoretical analyses reveal that the optical carrier transfer rate is enhanced by constructing interfacial internal electric fields and Fe-O-Mo charge transfer channels. For the formox process, heterojunctions possess superior HCHO-selective reaction paths and free energy transitions, optimizing the selectivity of HCHO and enhancing the reactivity. FeMo-2 shows a greatly improved performance compared to single Fe2 O3 ; the photocurrent density of FeMo-2 reaches 0.66 mA cm-2 , which is 3.88 times that of Fe2 O3 (0.17 mA cm-2 ), and the Faraday efficiency of the CH3 OH-to-HCHO conversion is 95.7 %. This work may deepen our understanding of interfacial charge separation and has potential for the production of HCHO and for conversion reactions of other small-molecule alcohols at cryogenic temperatures.

4.
Genes Dev ; 25(10): 1023-8, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21511872

RESUMO

Cryptochromes (CRYs) are blue-light photoreceptors that mediate various light responses in plants and animals. The signaling mechanism by which CRYs regulate light responses involves their physical interactions with COP1. Here, we report that CRY1 interacts physically with SPA1 in a blue-light-dependent manner. SPA acts genetically downstream from CRYs to regulate light-controlled development. Blue-light activation of CRY1 attenuates the association of COP1 with SPA1 in both yeast and plant cells. These results indicate that the blue-light-triggered CRY1-SPA1 interaction may negatively regulate COP1, at least in part, by promoting the dissociation of COP1 from SPA1. This interaction and consequent dissociation define a dynamic photosensory signaling mechanism.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Ciclo Celular/metabolismo , Criptocromos/metabolismo , Luz , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Técnicas do Sistema de Duplo-Híbrido
5.
Biomaterials ; 305: 122447, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38154441

RESUMO

Ferroptosis is a promising therapeutic approach for combating malignant cancers, but its effectiveness is limited in clinical due to the adaptability and self-repair abilities of cancer cells. Mitochondria, as the pivotal player in ferroptosis, exhibit tremendous therapeutic potential by targeting the intramitochondrial anti-ferroptotic pathway mediated by dihydroorotate dehydrogenase (DHODH). In this study, an albumin-based nanomedicine was developed to induce augmented ferroptosis in triple-negative breast cancer (TNBC) by depleting glutathione (GSH) and inhibiting DHODH activity. The nanomedicine (ATO/SRF@BSA) was developed by loading sorafenib (SRF) and atovaquone (ATO) into bovine serum albumin (BSA). SRF is an FDA-approved ferroptosis inducer and ATO is the only drug used in clinical that targets mitochondria. By combining the effects of SRF and ATO, ATO/SRF@BSA promoted the accumulation of lipid peroxides within mitochondria by inhibiting the glutathione peroxidase 4 (GPX4)-GSH pathway and downregulating the DHODH-coenzyme Q (CoQH2) defense mechanism, triggers a burst of lipid peroxides. Simultaneously, ATO/SRF@BSA suppressed cancer cell self-repair and enhanced cell death by inhibiting the synthesis of adenosine triphosphate (ATP) and pyrimidine nucleotides. Furthermore, the anti-cancer results showed that ATO/SRF@BSA exhibited tumor-specific killing efficacy, significantly improved the tumor hypoxic microenvironment, and lessened the toxic side effects of SRF. This work presents an efficient and easily achievable strategy for TNBC treatment, which may hold promise for clinical applications.


Assuntos
Ferroptose , Neoplasias de Mama Triplo Negativas , Humanos , Di-Hidro-Orotato Desidrogenase , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Peróxidos Lipídicos , Soroalbumina Bovina , Atovaquona , Glutationa , Linhagem Celular Tumoral , Microambiente Tumoral
6.
Biomaterials ; 300: 122205, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37348324

RESUMO

The use of overwhelming reactive oxygen species (ROS) attack has shown great potential for treating aggressive malignancies; however, targeting this process for further applications is greatly hindered by inefficiency and low selectivity. Here, a novel strategy for ROS explosion induced by tumor microenvironment-initiated lipid redox cycling was proposed, which was developed by using soybean phosphatidylcholine (SPC) to encapsulate lactate oxidase (LOX) and sorafenib (SRF) self-assembled nanoparticles (NPs), named LOX/SRF@Lip. SPC is not only the delivery carrier but an unsaturated lipid supplement for ROS explosion. And LOX catalyzes excessive intratumoral lactate to promote the accumulation of large amounts of H2O2. Then, H2O2 reacts with excessive endogenous iron ions to generate amounts of hydroxyl radical for the initiation of SPC peroxidation. Once started, the reaction will proceed via propagation to form new lipid peroxides (LPO), resulting to devastating LPO explosion and widespread oxidative damage in tumor cells. Furthermore, SRF makes contribution to mass LPO accumulation by inhibiting LPO elimination. Compared to normal tissue, tumor tissue has higher levels of lactate and iron ions. Therefore, LOX/SRF@Lip shows low toxicity in normal tissues, but generates efficient inhibition on tumor proliferation and metastasis, enabling excellent and safe tumor-specific therapy. This work offers new ideas on how to magnify anticancer effect of ROS through rational nanosystem design and tumor-specific microenvironment utilization.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral , Oxirredução , Peróxidos Lipídicos , Sorafenibe , Ferro , Linhagem Celular Tumoral
7.
Sheng Li Ke Xue Jin Zhan ; 43(6): 427-32, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23520761

RESUMO

Neuropathic pain is caused by lesion or disease of somatosensory system. The glial cell includes astrocyte and microglia in central nervous system (CNS), as well as satellite cell and Schwann cell in peripheral nervous system (PNS). Neural lesion activates the glial cell, inducing its morphology changes and certain protein expression. By interacting with neurons, the glial cell plays important roles in both the initiation and maintenance of neuropathic pain. In this review, we present recent progress in the study of glial mechanisms underlying neuropathic pain.


Assuntos
Neuralgia/fisiopatologia , Neuroglia/fisiologia , Humanos
8.
Front Chem ; 10: 931201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034673

RESUMO

Herein, we reported that KOH impregnation can generate a large number of porous structures with fruitful nitrogen self-doped groups during the carbonized process for poly (p-phenylene terephthalamide) fiber and poly (p-phenylene benzobisoxazole) fiber (denoted as PPTA and PBO, respectively). The intrinsical insulation, volume change, and shuttle effect of polysulfides then can be more significantly improved for the PBO-coated separator than the PPTA case. The discharge capacity primary achieves 1,322 mA h/g, which retains 827 mA h/g even after 200 cycles at 0.2 C for the cell with PBO-coated separator. The reversible specific discharge capacity maintains 841 mA h/g with a Coulomb efficiency of 99.7% at 5 C. The nitrogen self-doped nanocarbon particles are etched by KOH with the simple one-step preparation, which has promising application as Li-S battery cathode.

9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 39(1): 73-8, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21418803

RESUMO

OBJECTIVE: Vasoconstriction and vascular hypersensitivity to serotonin were previously shown in animal models of adventitia injury. We investigated the contribution of angiotensin II (AngII)/AngII receptors and oxidative stress to vascular contractility and reactivity in this model. METHODS: Wistar Kyoto rats were divided into 3 groups: normal (n = 6, no any intervention, only for measuring the serum AngII concentration), vehicle (n = 12, collared), and valsartan (n = 12, collared + valsartan 30 mg×kg(-1)×d(-1)). After one week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for one week. Blood flow and vascular reactivity to serotonin were determined one week after injury, the blood from left ventricle was taken to measure the serum AngII concentration by ELISA, and carotids were harvested for morphometry and Western blot analysis. RESULTS: Adventitia injury induced lumen cross-sectional area reduction (-44% vs. -5%), media diameter increase (62% vs. 10%), blood flow reduction [(2.79 ± 0.22) vs. (4.33 ± 0.84) ml/min] were significantly attenuated by valsartan. The increased vascular reactivity sensitivity to serotonin in vehicle group was also significantly reduced in valsartan group. Serum AngII concentration was significantly increased in vehicle group [(45.21 ± 4.52) pg/ml vs. (19.83 ± 0.5) pg/ml in normal rats, P = 0.0148] and the expression of AngII type 1 (AT(1)) receptor, AngII type 2 (AT(2)) receptor, as well as p22(phox) in collared arteries were significantly upregulated. Valsartan did not affect the AT(1) receptor expression but further increased serum AngII concentration [(89.73 ± 20.44) pg/ml vs. (45.21 ± 4.52) pg/ml, P = 0.001], and AT(2) receptor expression, while downregulated p22(phox) expressions. CONCLUSIONS: Collar-induced adventitia injury resulted in chronic vasoconstriction and vascular hypersensitivity to serotonin via increased serum AngII level, upregulated AngII receptors expression in the vascular well, and activated local oxidative stress. These changes could be blocked by valsartan suggesting a crucial role of AngII/AngII receptors on vascular contractility and reactivity changes in this model.


Assuntos
Artérias Carótidas/efeitos dos fármacos , Tecido Conjuntivo/patologia , Tetrazóis/farmacologia , Valina/análogos & derivados , Vasoconstrição/efeitos dos fármacos , Angiotensina II/metabolismo , Animais , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Masculino , Estresse Oxidativo , Ratos , Ratos Endogâmicos WKY , Receptores de Angiotensina/metabolismo , Valina/farmacologia , Valsartana
10.
Medicine (Baltimore) ; 100(22): e26064, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34087850

RESUMO

OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of acupuncture in the treatment of urinary retention after hysterectomy in women. METHODS: This research searched for 6 database documents, and the deadline is July 23, 2020. This study included a randomized controlled trial of women with urinary retention after hysterectomy. These randomized controlled trials compare acupuncture with bladder function training or other nonacupuncture treatments, and measure urodynamics, effectiveness (BR), and urinary tract infection rates (UIR). Four independent reviewers participated in data extraction and evaluation. Assess the risk of bias in each article, and conduct a meta-analysis according to the type of acupuncture. The result is expressed as a mean difference (MD) or relative risk (RR) with a 95% confidence interval (CI). RESULTS: The meta-analysis contains 12 studies. Most studies indicate low risk or unknown risk, but the GRADE scores of the combined results show low or moderate levels. After the combined analysis, we found that acupuncture versus bladder function exercise and other nonacupuncture therapies can significantly improve the values of post voided residual urine (PVR) (MD = -25.29; 95% CI [-30.45 to -20.73]), maximal cystometric capacity (MD = 39.54; 95% CI [10.30-68.78]), bladder capacity for first voiding desire (MD = -61.98; 95% CI [-90.69 to -33.26]) and maximal flow rate (MFR) (MD = 7.58; 95% CI [5.19-9.97]). And compared with the control group, acupuncture still has advantages in BR (RR = 1.36; 95% CI [1.18-1.56]) and UIR (RR = 0.22; 95% CI [0.08-0.82]). These heterogeneities have been resolved through subgroup analysis, and their main sources are related to different intervention times, the time to start the intervention, and different PVR requirements. CONCLUSIONS: There is insufficient evidence that acupuncture can increase the patient's MFR, BR, and UIR. However, acupuncture can effectively improve the PVR, maximal cystometric capacity, and bladder capacity for first voiding desire values of patients with urinary retention after hysterectomy. Although limited due to the quality and methodological limitations of the included studies, acupuncture can still be used as an effective and safe treatment for women with urinary retention after hysterectomy. REGISTRATION: The research has been registered and approved on the PROSPERO website. The registration number is CRD42019119238.


Assuntos
Terapia por Acupuntura/métodos , Histerectomia/efeitos adversos , Retenção Urinária/etiologia , Retenção Urinária/terapia , Terapia por Exercício/métodos , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Infecções Urinárias/epidemiologia
11.
Nat Commun ; 12(1): 1675, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723264

RESUMO

The surface electron density significantly affects the photocatalytic efficiency, especially the photocatalytic CO2 reduction reaction, which involves multi-electron participation in the conversion process. Herein, we propose a conceptually different mechanism for surface electron density modulation based on the model of Au anchored CdS. We firstly manipulate the direction of electron transfer by regulating the vacancy types of CdS. When electrons accumulate on vacancies instead of single Au atoms, the adsorption types of CO2 change from physical adsorption to chemical adsorption. More importantly, the surface electron density is manipulated by controlling the size of Au nanostructures. When Au nanoclusters downsize to single Au atoms, the strong hybridization of Au 5d and S 2p orbits accelerates the photo-electrons transfer onto the surface, resulting in more electrons available for CO2 reduction. As a result, the product generation rate of AuSA/Cd1-xS manifests a remarkable at least 113-fold enhancement compared with pristine Cd1-xS.

12.
Front Genet ; 12: 743560, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712268

RESUMO

Rheumatoid arthritis (RA) and osteoarthritis (OA) are two most common rheumatic diseases in the world. Although there are standard methods for the diagnosis of both RA and OA, the differentials in some cases are poor. With deepening research, the role of autophagy in maintaining cell homeostasis and thus enabling cells adapt to external environments has become increasingly prominent. Both RA and OA, two diseases with inherent differences in pathogenesis, gradually show differences in autophagy levels. Our study therefore aims to further understand differences in pathogenesis of RA and OA through in-depth studies of autophagy in RA and OA. We also define appropriate autophagy-related markers as recognition indicators. Differences in autophagy levels between RA and OA were found based on analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) and single-sample gene set enrichment (ssGSEA). These differences were mainly caused by 134 differentially expressed genes (DEGs). In two autophagy-related genes, CXCR4 and SERPINA1, there existed significant statistical difference between RA and OA. An autophagy related index (ARI) was thus successfully constructed based on CXCR4 and SERPINA by binary logistic regression of the generalized linear regression (GLR) algorithm. Pearson analysis indicated that the expression of CXCR4, SERPINA1, and ARI were closely correlated with autophagy scores and immune infiltration. Moreover, ARI showed high disease identification through receiver operating characteristic (ROC) analysis (AUCtesting cohort = 0.956, AUCtraining cohort = 0.867). These results were then verified in GSE12021 independent cohort. In conclusion, ARI associated with autophagy and immune infiltration was successfully constructed for accurately identifying OA and RA. The index, thus, has great potential in clinical applications.

13.
Front Chem ; 9: 763892, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765588

RESUMO

Accumulation of lipids in the myocardium contributes to the development of cardiac dysfunctions and various chronic diseases, such as diabetic cardiomyopathy (DCM). Curcumin (Cur) can relieve lipid accumulation problems, but its efficiency is limited by poor water solubility and biocompatibility. Herein, gold nanoclusters (AuNCs) were used to improve the efficiency of Cur, and the conjugates Curcumin-AuNCs (AuCur) were developed. In the treatment of high-fat-induced myocardial cell damage, we found that AuCur could effectively reduce intracellular lipid accumulation, the increase of reactive oxygen species (ROS), the increase of mitochondrial division, and the increase of apoptosis compared with Cur. AuCur decreased the expression of the peroxisome proliferator-activated receptors-α subtype (PPARα), and the therapeutic effect of AuCur was canceled when the expression of PPARα was enhanced. For the above reasons, AuCur treated the toxic effect of high lipid on cardiomyocytes by regulating PPARα, providing a new idea and method for the treatment of DCM.

14.
J Colloid Interface Sci ; 573: 71-77, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32272299

RESUMO

Through direct addition of inorganic zinc ions into the solution of indium phosphide quantum dots (InP QDs) at ambient environment, we here present a facile but effective method to modify InP QDs for photocatalytic hydrogen evolution from hydrogen sulfide (H2S). X-ray diffraction patterns and transmission electron microscopic images demonstrate that zinc ions have no significant influence on the crystal structure and morphology of InP QDs, while X-ray photoemission spectra and UV-Vis diffuse and reflectance spectra indicate that zinc ions mainly adsorbed on the surface of InP QDs. Photocatalytic results show the average hydrogen evolution rate has been enhanced to 2.9 times after modification and H2S has indeed involves in the hydrogen evolution process. Steady-state and transient photoluminescence spectra prove that zinc ions could effectively eliminate the surface traps on InP QDs, which is crucial to suppress the recombination of charge carriers. In addition, the electrostatic interaction between zinc ions and the surface sulfide from InP QDs could mitigate the repulsion between QDs and sulfide/hydrosulfide, which may promote the surface oxidative reaction during photocatalysis. This work avoids the traditional harsh and complicated operations required for surface passivation of QDs, which offers a convenient way for optimization of QDs in photocatalysis.

15.
Chem Commun (Camb) ; 56(91): 14227-14230, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33118562

RESUMO

Alkaline-earth metal Ca2+ modified CdS nanocrystals have been designed for the first time for highly efficient H2 evolution from hydrogen sulfide (H2S) with Na2SO3 as a favourable reaction medium. The advantage of Na2SO3 was revealed by an electrochemical test, and the conversion of Na2SO3 during the reaction was carefully studied. Particularly, most of Na2SO3 was converted into Na2S2O3. Highly value-added utilization of waste H2S is therefore achieved via photocatalysis.

16.
J Glob Antimicrob Resist ; 16: 98-104, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30213718

RESUMO

OBJECTIVES: Staphylococcus aureus (SA) is a major pathogen causing dairy cow mastitis and endometritis. Recently, animal-derived SA strains pose a serious public-health threat. However, little is known about antimicrobial resistance and virulence factors of SA isolated from dairy cows in Xinjiang, China. In this study, antimicrobial resistance, virulence gene profiles and genotypes of SA from clinical mastitis and endometritis in dairy cows were investigated. METHODS: A total of 337 clinical samples (186 milk samples from clinical mastitis cases and 151 endometritis swab samples) were collected from 15 large-scale dairy farms and were screened for SA. All SA isolates were subjected to antimicrobial susceptibility testing, detection of virulence genes and molecular typing. RESULTS: A total of 155 SA strains were isolated; 22 (14.2%) were methicillin-resistant S. aureus (MRSA). Resistance of MRSA isolates was significantly higher than that of methicillin-susceptible S. aureus (MSSA). The percentage of virulence genes varied between MSSA and MRSA. The strains could be divided into two SCCmec types (I and IVa), three agr types (I, II and III) and four spa types (t779, t2883, t13751 and t1939). MLST identified 14 sequence types, among which ST1 and ST9 had relatively high detection rates. CONCLUSIONS: These findings revealed that ST9-t1939-agrI was the main genotype of MSSA, whilst ST1-SCCmecI-t1939-agrI was the main genotype of MRSA from dairy cows. More significantly, a novel ST (STX) was identified for the first time. The majority of SA strains from dairy cows were multidrug-resistant and carried multiple virulence genes, posing a potential public-health risk.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Fatores de Virulência/genética , Animais , Técnicas de Tipagem Bacteriana , Bovinos , China , Indústria de Laticínios , Feminino , Genótipo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Virulência
17.
J Zhejiang Univ Sci B ; 19(1): 71-78, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29308610

RESUMO

OBJECTIVE: This study investigated complementary feeding practices among four ethnic groups (Han, Uygur, Tibetan, and Zhuang) based on a cross-sectional survey in rural western China. METHODS: In 2005, a stratified multistage cluster random sampling method was used to recruit 9712 children (7411 Han, 1032 Uygur, 678 Tibetan, and 591 Zhuang) between 6 and 35 months of age and their mothers from 45 counties in 10 provinces (autonomous regions, municipalities) in western China. RESULTS: The rates of early introduction (before 6 months) of complementary foods in four ethnic groups (Han, Uygur, Tibetan, and Zhuang) were 71.30%, 95.95%, 82.40%, and 72.30%, respectively. The Infant and Child Feeding Index (ICFI) for Uygur and Tibetan children was lower than that for Han children at all age groups. Uygur children were more likely to have unqualified ICFI compared with Han children in a multivariate logistic regression (odds ratio (OR)=5.138, 95% confidence interval (CI): 4.340-6.084). A higher level of maternal education, greater family wealth, and the availability of complementary feeding educational materials decreased the likelihood of an unqualified ICFI. The nutritional status of children (Han, Tibetan, and Zhuang) with qualified ICFI was better than that for children with unqualified ICFI. CONCLUSIONS: Appropriate interventions are required to improve complementary feeding practices in rural western China.


Assuntos
Comportamento Alimentar/etnologia , Fenômenos Fisiológicos da Nutrição do Lactente/etnologia , Adulto , Povo Asiático , Pré-Escolar , China , Análise por Conglomerados , Estudos Transversais , Escolaridade , Etnicidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multivariada , Estado Nutricional , Razão de Chances , População Rural , Classe Social , Inquéritos e Questionários , Adulto Jovem
18.
J Ethnopharmacol ; 131(2): 300-5, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20600751

RESUMO

OBJECTIVE: Tongxinluo (TXL) is a traditional Chinese medicine that is developed on the meridian theory of traditional Chinese medicine, with the function of alleviating the angina. The present study was undertaken to explore the molecular mechanism of TXL in treating the pectoris angina through observing the effectiveness of TXL superfine powder on the vasoconstriction and the activation of RhoA/Rho-kinase pathway induced by the injury of the adventitia. METHODS: 36 male Wistar Kyoto rats were assigned to 3 treatments (n=12): vehicle, TXL (400 mg kg(-1) day(-1)) and fasudil (15 mg kg(-1) day(-1)). After 1 week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for 1 week. Blood flow and vascular reactivity to serotonin were determined 1 week after injurying, the both sides of carotids were harvested for morphometry, Western blotting analysis and RT-PCR analysis. RESULTS: Adventitia injury leaded to histological changes of vasoconstriction with the lumen cross-sectional area of 44.7% (p<0.001) decreasing and the media diameter of 62.31% (p<0.001) increasing, accompanying by the reduction of the blood flow and the increase of vascular reactivity sensitivity to serotonin. Treatment with both TXL superfine powder and fasudil can prevent the development of vasoconstriction, improve the carotid blood flow and normalize the vascular hypersensitivity to serotonin. Adventitia injuring of the rat carotid increased the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 1.78-fold (p<0.05) and >2-fold respectively (p<0.05). TXL reduced the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 54.2% (p<0.05) and 57.1% (p<0.05) respectively in collared arteries. Fasudil restrained the p-MYPT1(Thr696) protein expression by 63.8% (p<0.05) in collared arteries, did not affect the collar-induced the increase of Rho-kinase mRNA expression (p>0.05). CONCLUSIONS: Treatment with TXL, similar to that with fasudil, can effectively prevent collar-induced vasoconstriction and vascular hyperreactivity to serotonin through inhibiting the RhoA/Rho-kinase pathway.


Assuntos
Artérias Carótidas/efeitos dos fármacos , Doenças das Artérias Carótidas/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Fitoterapia , Vasoconstrição/efeitos dos fármacos , Vasodilatadores/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Animais , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Tecido Conjuntivo/lesões , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/uso terapêutico , Hemorreologia/efeitos dos fármacos , Masculino , Pós , Proteína Fosfatase 1/genética , Proteína Fosfatase 1/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Serotonina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Túnica Média/efeitos dos fármacos , Túnica Média/patologia , Vasodilatadores/uso terapêutico , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
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