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1.
J Biomol Struct Dyn ; : 1-13, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345053

RESUMO

Pigment epithelium-derived factor (PEDF) could bind to vascular endothelial growth factor receptor 2 (VEGFR2) and inhibit its activation induced by VEGF. But how PEDF affects VEGFR2 pathway is still poorly understood. In this study, we elucidated the precise mechanism underlying the interaction between PEDF and VEGFR2, and subsequently corroborated our findings using a rat AMI model. PEDF prevented endocytosis of VE-cadherin induced by hypoxia, thereby protecting the endothelium integrity. A three-dimensional model of the VEGFR2-PEDF complex was constructed by protein-protein docking method. The results showed that the VEGFR2-PEDF complex was stable during the simulation. Hydrogen bonds, binding energy and binding modes were analyzed during molecular dynamics simulations, which indicated that hydrogen bonds and hydrophobic interactions were important for the recognition of VEGFR2 with PEDF. In addition, the results from exudation of fibrinogen suggested that PEDF inhibits vascular leakage in acute myocardial infarction and confirmed the critical role of key amino acids in the regulation of endothelial cell permeability. This observation is also supported by echocardiography studies showing that the 34mer peptide sustained cardiac function during acute myocardial infarction. Besides, PEDF and 34mer could inhibit the aggregation of myofiber in the heart and promoted the formation of a dense cell layer in cardiomyocytes, which suggested that PEDF and 34mer peptide protect against AMI-induced cardiac dysfunction. These results suggest that PEDF inhibits the phosphorylation of downstream proteins, thereby preventing vascular leakage, which provides a new therapeutic direction for the treatment of acute myocardial infarction.Communicated by Ramaswamy H. Sarma.

2.
Sci China Life Sci ; 67(2): 286-300, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897614

RESUMO

We previously demonstrated that normal high-density lipoprotein (nHDL) can promote angiogenesis, whereas HDL from patients with coronary artery disease (dHDL) is dysfunctional and impairs angiogenesis. Autophagy plays a critical role in angiogenesis, and HDL regulates autophagy. However, it is unclear whether nHDL and dHDL regulate angiogenesis by affecting autophagy. Endothelial cells (ECs) were treated with nHDL and dHDL with or without an autophagy inhibitor. Autophagy, endothelial nitric oxide synthase (eNOS) expression, miRNA expression, nitric oxide (NO) production, superoxide anion (O2•-) generation, EC migration, and tube formation were evaluated. nHDL suppressed the expression of miR-181a-5p, which promotes autophagy and the expression of eNOS, resulting in NO production and the inhibition of O2•- generation, and ultimately increasing in EC migration and tube formation. dHDL showed opposite effects compared to nHDL and ultimately inhibited EC migration and tube formation. We found that autophagy-related protein 5 (ATG5) was a direct target of miR-181a-5p. ATG5 silencing or miR-181a-5p mimic inhibited nHDL-induced autophagy, eNOS expression, NO production, EC migration, tube formation, and enhanced O2•- generation, whereas overexpression of ATG5 or miR-181a-5p inhibitor reversed the above effects of dHDL. ATG5 expression and angiogenesis were decreased in the ischemic lower limbs of hypercholesterolemic low-density lipoprotein receptor null (LDLr-/-) mice when compared to C57BL/6 mice. ATG5 overexpression improved angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Taken together, nHDL was able to stimulate autophagy by suppressing miR-181a-5p, subsequently increasing eNOS expression, which generated NO and promoted angiogenesis. In contrast, dHDL inhibited angiogenesis, at least partially, by increasing miR-181a-5p expression, which decreased autophagy and eNOS expression, resulting in a decrease in NO production and an increase in O2•- generation. Our findings reveal a novel mechanism by which HDL affects angiogenesis by regulating autophagy and provide a therapeutic target for dHDL-impaired angiogenesis.


Assuntos
MicroRNAs , Humanos , Camundongos , Animais , MicroRNAs/metabolismo , Células Endoteliais/metabolismo , Angiogênese , Camundongos Endogâmicos C57BL , Autofagia/genética
3.
Inorg Chem ; 62(14): 5780-5790, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36976898

RESUMO

Achieving long-term stable deep desulfurization at room temperature and recovering high value-added sulfone products is a challenge at present. Herein, a series of catalysts [Cnmim]5VW12O40Br (CnVW12, 1-alkyl-3-methylimidazolium bromide tungstovanadate, n = 4, 8, 16) were presented for the room temperature catalytic oxidation of dibenzothiophene (DBT) and its derivatives. Factors affecting the reaction process, such as the amount of catalyst, oxidant, and temperature, were systematically discussed. C16VW12 showed higher catalytic performance, and 100% conversion and selectivity could be achieved in 50 min with only 10 mg. The mechanism study showed that the hydroxyl radical was the active radical in the reaction. Benefiting from the "polarity strategy", the sulfone product accumulated after 23 cycles in a C16VW12 system, and the yield and purity were about 84% and 100%, respectively.

4.
J Laparoendosc Adv Surg Tech A ; 32(2): 158-164, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33651638

RESUMO

Objective: To investigate the efficacy and safety of cold snare endoscopic mucosal resection (CS-EMR) and hot snare endoscopic mucosal resection (HS-EMR) for colorectal polyps with diameters of 6-9 mm. Methods: Retrospective analysis was performed on the clinical data of 485 patients with colorectal polyps (6-9 mm in size) who were treated with CS-EMR or HS-EMR in the endoscopy center of Hangzhou Third People's Hospital from January 2017 to December 2019. Colorectal polyps were lifted by submucosal injection of normal saline. The CS-EMR group used a cold snare to remove the lifting polyps, while the HS-EMR group used a hot snare. Propensity score matching analysis with 1:1 matching and the nearest neighbor matching method were performed to ensure well-balanced characteristics of the CS-EMR and HS-EMR groups. Matching factors included age, gender, body mass index, blood routine, coagulation indicators, polyp site, size, number, and morphology. This resulted in a balanced cohort of 128 patients per group. Polyp recovery, complications, clipping for disclosure, and length of hospital stay were compared after matching. t-Tests, χ2 tests, McNemar's tests, and Fisher's exact test were used for comparison between the two groups before and after matching. Results: There were no differences between the two groups of intraoperative and postoperative bleeding (P > .05), but the CS-EMR clipping rate was lower than the HS-EMR group (P < .01). There was a higher incidence of post-polypectomy syndrome (PPS) (P = .03) and longer hospital stays (P < .01) in the HS-EMR group than the CS-EMR group. Conclusions: Compared with HS-EMR, CS-EMR is more convenient to operate, with a low incidence of PPS, clipping rates, and short hospital stays. It is a safe and effective removal method for 6-9 mm colorectal polyps.


Assuntos
Pólipos do Colo , Ressecção Endoscópica de Mucosa , Pólipos do Colo/cirurgia , Colonoscopia , Humanos , Pontuação de Propensão , Estudos Retrospectivos
5.
Clin Cosmet Investig Dermatol ; 14: 129-136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33584099

RESUMO

OBJECTIVE: To investigate the role of Helicobacter pylori (HP) eradication in chronic spontaneous urticaria (CSU) treatment. METHODS: Retrospective analysis was performed on the clinical data of 522 patients with CSU who underwent a HP breath test in Hangzhou Third People's Hospital between January 2018 and December 2019. The CSU-HP(+) group consisted of patients with CSU and HP infection, who were treated with antihistamines combined with HP eradication therapy. The CSU-HP(-) group consisted of patients with CSU alone, who were treated with antihistamines. Propensity score matching (PSM) analysis, using the nearest neighbor matching method on a 1:1 basis, was performed to ensure the characteristics of the CSU-HP(+) and CSU-HP(-) groups were similar. Factors, including age, gender, white blood cells, red blood cells, platelets, alanine transaminase, creatinine, immunoglobulin E, and pre-treatment urticaria activity score (UAS), were matched to obtain a balanced cohort of patients in each group. Therapeutic effects were compared after matching. t-tests, Χ 2 test, and McNemar's test were used for comparison between the two groups before and after matching. RESULTS: Patients in the CSU-HP(+) group reported significantly more gastrointestinal symptoms than those in the CSU-HP(-) group. UAS scores in the second week of treatment were significantly different between the two groups. After 3 months, the recurrence rate in the CSU-HP(+) group was lower than in the CSU-HP(-) group. CONCLUSION: Eradication of HP infection in patients with CSU helps relieve gastrointestinal symptoms, improves the therapeutic effect of CSU within 2 weeks, and reduces the recurrence rate 3 months after treatment.

6.
Redox Biol ; 36: 101642, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32863238

RESUMO

Normal high-density lipoprotein (nHDL) in normal, healthy subjects is able to promote angiogenesis, but the mechanism remains incompletely understood. HDL from patients with coronary artery disease may undergo a variety of oxidative modifications, rendering it dysfunctional; whether the angiogenic effect is mitigated by such dysfunctional HDL (dHDL) is unknown. We hypothesized that dHDL compromises angiogenesis. The angiogenic effects of nHDL and dHDL were assessed using endothelial cell culture, endothelial sprouts from cardiac tissue from C57BL/6 mice, zebrafish model for vascular growth and a model of impaired vascular growth in hypercholesterolemic low-density lipoprotein receptor null(LDLr-/-)mice. MiRNA microarray and proteomic analyses were used to determine the mechanisms. Lipid hydroperoxides were greater in dHDL than in nHDL. While nHDL stimulated angiogenesis, dHDL attenuated these responses. Protein and miRNA profiles in endothelial cells differed between nHDL and dHDL treatments. Moreover, nHDL suppressed miR-24-3p expression to increase vinculin expression resulting in nitric oxide (NO) production, whereas dHDL delivered miR-24-3p to inhibit vinculin expression leading to superoxide anion (O2•-) generation via scavenger receptor class B type 1. Vinculin was required for endothelial nitric oxide synthase (eNOS) expression and activation and modulated the PI3K/AKT/eNOS and ERK1/2 signaling pathways to regulate nHDL- and VEGF-induced angiogenesis. Vinculin overexpression or miR-24-3p inhibition reversed dHDL-impaired angiogenesis. The expressions of vinculin and eNOS and angiogenesis were decreased, but the expression of miR-24-3p and lipid hydroperoxides in HDL were increased in the ischemic lower limbs of hypercholesterolemic LDLr-/- mice. Overexpression of vinculin or miR-24-3p antagomir restored the impaired-angiogenesis in ischemic hypercholesterolemic LDLr-/- mice. Collectively, nHDL stimulated vinculin and eNOS expression to increase NO production by suppressing miR-24-3p to induce angiogenesis, whereas dHDL inhibited vinculin and eNOS expression to enhance O2•- generation by delivering miR-24-3p to impair angiogenesis, and that vinculin and miR-24-3p may be therapeutic targets for dHDL-impaired angiogenesis.


Assuntos
Doença da Artéria Coronariana , MicroRNAs , Animais , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/genética , Células Endoteliais , Voluntários Saudáveis , Humanos , Lipoproteínas HDL , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/genética , Fosfatidilinositol 3-Quinases , Proteômica , Peixe-Zebra
8.
World J Clin Cases ; 6(9): 291-295, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30211210

RESUMO

Acute pancreatitis is rarely associated with drugs. Acetaminophen overdose is a well-known cause of hepatic toxicity, but drug-induced pancreatitis is rarely reported, especially after mild overdose. A 32-year-old woman presented with nausea and vomiting for 12 h, but no abdominal pain following an overdose of eight Tylenol tablets containing acetaminophen (325 mg acetaminophen per tablet). Laboratory results on admission showed abnormal amylase and lipase levels but completely normal liver function. Magnetic resonance cholangiopancreatography revealed mild swelling of the pancreas without fluid collection around the pancreas. The patient complained of severe abdominal pain five days after admission when attempting to drink water and liquids. Eight days after admission, fluid around the pancreas was observed by computed tomography. The patient was subsequently diagnosed with acetaminophen-induced acute pancreatitis after exclusion of common causes. Routine treatment for pancreatitis and N-acetylcysteine were administered to prevent disease progression. The patient was discharged in good condition.

9.
J Cardiovasc Pharmacol ; 72(4): 176-185, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29985281

RESUMO

Simvastatin treatment is cardioprotective in patients undergoing noncoronary artery cardiac surgery. However, the mechanisms by which simvastatin treatment protects the myocardium under these conditions are not fully understood. Seventy patients undergoing noncoronary cardiac surgery, 35 from a simvastatin treatment group and 35 from a control treatment group, were enrolled in our clinical study. Simvastatin (20 mg/d) was administered preoperatively for 5-7 days. Myocardial tissue biopsies were taken before and after surgery. Apoptosis was detected by TUNEL staining. The expressions of Bcl-2 and Bak in myocardial tissue were detected by immunoblotting. The expressions of miRNA and Bcl-2 mRNA were detected by quantitative real-time polymerase chain reaction assays. Cardiomyocytes were isolated from rat and cultured cells. MiR-15a-5p mimic was transfected into cardiomyocytes, and the Bcl-2 was detected by immunoblotting. TUNEL staining showed significantly less myocardial apoptosis in the simvastatin treatment group when compared with the control treatment group. Protein expression of Bcl-2 was increased in the simvastatin treatment group before surgery, and Bak expression was increased in the control treatment group after surgery. Further comparisons showed that Bcl-2/Bak ratios were reduced in the control treatment group but were not significantly changed in the simvastatin treatment group after surgery. Furthermore, microarray assays revealed that miR-15a-5p was significantly decreased by simvastatin treatment. This was validated by quantitative real-time polymerase chain reaction analysis. MiR-15a-5p was predicted to target Bcl-2 mRNA at nucleotide positions 2529-2536. This was validated by luciferase binding assays. Coincident with the change in miR-15a-5p, the mRNA expression of Bcl-2 was increased in the simvastatin treatment group. MiR-15a-5p mimic significantly inhibited Bcl-2 expression in cardiomyocytes. Our findings strongly suggest that simvastatin treatment preoperatively protected the myocardium in patients undergoing noncoronary artery cardiac surgery, at least in part, by inhibiting apoptosis via suppressing miR-15a-5p expression, leading to increasing expression of Bcl-2 and decreasing expression of Bak.


Assuntos
Apoptose/efeitos dos fármacos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Cardiopatias/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , MicroRNAs/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Sinvastatina/administração & dosagem , Adulto , Animais , Células Cultivadas , China , Esquema de Medicação , Feminino , Cardiopatias/genética , Cardiopatias/metabolismo , Cardiopatias/patologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sinvastatina/efeitos adversos , Resultado do Tratamento , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo
10.
J Mol Cell Cardiol ; 112: 40-48, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28870504

RESUMO

Endothelial dysfunction is an early stage of atherosclerosis. We recently have shown that 25-hydroxycholesterol found in atherosclerotic lesions could impair endothelial function and vasodilation by uncoupling and inhibiting endothelial nitric oxide synthase (eNOS). 1-Palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC), the oxidation product of oxidized low-density lipoprotein, is another proinflammatory lipid and has also been found in atherosclerotic lesions. However, whether POVPC promotes atherosclerosis like 25-hydroxycholesterol remains unclear. The purpose of this study was to explore the effects of POVPC on endothelial function and vasodilation. Human umbilical vein endothelial cells (HUVECs) were incubated with POVPC. Endothelial cell proliferation, migration and tube formation were measured. Nitric oxide (NO) production and superoxide anion generation (O2-) were determined. The expression and phosphorylation of endothelial nitric oxide synthase (eNOS), AKT, PKC-ßII and P70S6K as well as the association of eNOS and heat shock protein 90 (HSP90) were detected by immunoblotting and immunoprecipitation. Endothelial cell apoptosis was monitored by TUNEL staining. The expression of Bcl-2, Bax, and Cleaved Caspase 3 were detected by immunoblotting. Finally, aortic ring from C57BL6 mice were isolated and treated with POVPC and the endothelium-dependent vasodilation was evaluated. POVPC significantly inhibited HUVECs proliferation, migration, tube formation, decreased NO production but increased O2- generation. POVPC inhibited the phosphorylation of Akt and eNOS at Ser1177, increased activation of PKC-ßII, P70S6K and the phosphorylation of eNOS at Thr495, reduced the association of HSP90 with eNOS. Meanwhile, POVPC induced endothelial cell apoptosis by inhibiting Bcl-2 expression, increasing Bax and cleaved caspase-3 expressions as well as caspase-3 activity and impaired endothelium-dependent vasodilation. These data demonstrated that POVPC impaired endothelial function by uncoupling and inhibiting eNOS as well as by inducing endothelial cell apoptosis. Therefore, POVPC may play an important role in the development of atherosclerosis and may be considered as a potential therapeutic target for atherosclerosis.


Assuntos
Células Endoteliais da Veia Umbilical Humana/patologia , Óxido Nítrico Sintase Tipo III/metabolismo , Éteres Fosfolipídicos/farmacologia , Vasodilatação/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Oxirredução , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxidos/metabolismo
11.
Biochem Biophys Res Commun ; 487(3): 552-559, 2017 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-28427943

RESUMO

Increased evidence has showed that normal high density lipoprotein (HDL) could convert to dysfunctional HDL in diseases states including coronary artery disease (CAD), which regulated vascular endothelial cell function differently. Long non-coding RNAs (lncRNAs) play an extensive role in various important biological processes including endothelial cell function. However, whether lncRNAs are involved in the regulation of HDL metabolism and HDL-induced changes of vascular endothelial function remains unclear. Cultured human umbilical vein endothelial cells (HUVECs) were treated with HDL from healthy subjects and patients with CAD and hypercholesterolemia for 24 h, then the cells were collected for lncRNA-Seq and the expressions of lncRNAs, genes and mRNAs were identified. The bioinformatic analysis was used to evaluate the relationship among lncRNAs, encoding genes and miRNAs. HDL from healthy subjects and patients with CAD and hypercholesterolemia leaded to different expressions of lncRNAs, genes and mRNAs, and further analysis suggested that the differentially expressed lncRNAs played an important role in the regulation of vascular endothelial function. Thus, HDL from patients with CAD and hypercholesterolemia could cause abnormal expression of lncRNAs in vascular endothelial cells to affect vascular function.


Assuntos
Doença da Artéria Coronariana/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Lipoproteínas HDL/metabolismo , RNA Longo não Codificante/genética , Células Cultivadas , Feminino , Humanos , Lipoproteínas HDL/administração & dosagem , Masculino , Pessoa de Meia-Idade , RNA Longo não Codificante/metabolismo
12.
J Transl Med ; 15(1): 4, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28049487

RESUMO

BACKGROUND: We previously demonstrated that endothelial microparticles (EMPs) are increased in mitral valve diseases and impair valvular endothelial cell function. Perioperative systemic inflammation is an important risk factor and complication of cardiac surgery. In this study, we investigate whether EMPs increase in congenital heart diseases to promote inflammation and endothelial dysfunction. METHODS: The level of plasma EMPs in 20 patients with atrial septal defect (ASD), 23 patients with ventricular septal defect (VSD), and 30 healthy subjects were analyzed by flow cytometry. EMPs generated from human umbilical vascular endothelial cells (HUVECs) were injected into C57BL6 mice, or cultured with HUVECs without or with siRNAs targeting P38 MAPK. The expression and/or phosphorylation of endothelial nitric oxide synthase (eNOS), P38 MAPK, and caveolin-1 in mouse heart and/or in cultured HUVECs were determined. We evaluated generation of nitric oxide (NO) in mouse hearts, and levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in cultured HUVECs and in mice. RESULTS: EMPs were significantly elevated in patients with ASD and VSD, especially in those with pulmonary hypertension when compared with controls. EMPs increased caveolin-1 expression and P38 MAPK phosphorylation and decreased eNOS phosphorylation and NO production in mouse hearts. EMPs stimulated P38 MAPK expression, TNF-α and IL-6 production, which were all inhibited by siRNAs targeting P38 MAPK in cultured HUVECs. CONCLUSIONS: EMPs were increased in adult patients with congenital heart diseases and may contribute to increased inflammation leading to endothelial dysfunction via P38 MAPK-dependent pathways. This novel data provides a potential therapeutic target to address important complications of surgery of congenial heart disease.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/metabolismo , Cardiopatias Congênitas/patologia , Cardiopatias Congênitas/fisiopatologia , Adulto , Animais , Caveolina 1/metabolismo , Demografia , Ecocardiografia Doppler , Endotélio Vascular/diagnóstico por imagem , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Feminino , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico por imagem , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Interleucina-6/sangue , Masculino , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Fator de Necrose Tumoral alfa/sangue , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Zhonghua Yi Shi Za Zhi ; 41(5): 271-4, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22340004

RESUMO

Chinese medicine licensing examinations were hosted by local health institution eight times in Guangzhou from 1922 to 1942. By analyzing the policy, implementation topics and responses of the 8 examinations, it could be found that eligibility of examinees, test subjects and the examination format underwent changes and the evaluation system had gradually been improved. But influenced by the dispute between western medicine and Traditional Chinese Medicine, there are still limitations and lack of standardization for the examinations.

14.
Talanta ; 82(3): 1068-71, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20678670

RESUMO

The electrochemistry and electrochemiluminescence (ECL) of novel three-dimensional nanostructured Ru(bpy)(3)(2+)/Ni(OH)(2) microspheres were investigated for the first time. The negatively charged porous Ni(OH)(2) microspheres composed of Ni(OH)(2) nanowires were specifically designed to interact with Ru(bpy)(3)(2+). The large surface area and porous structure of Ni(OH)(2) microspheres enhance loading of Ru(bpy)(3)(2+) and mass transport of the model analyte, tripropylamine (TPA). Excellent ECL performance of the presented sensor was achieved including good stability and wide linear range from 7.7x10(-10) to 3.8x10(-3)M with the detection limit of 2.6x10(-10)M to TPA.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(2): 391-4, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20384131

RESUMO

It is the first time ionic liquid was applied to gas solvent sublation, which established a new method for separation/enrichment of tetracyclines (TCs) antibiotic based on ionic liquid gas solvent sublation. The optimizing experimental conditions were as follows: the mixture of ionic liquid 1-hexyl-3-methylimidazo lium hexafluorophosphats and ethyl acetate ([Hmim] PF6-EA, phi = 1/0.9) can be used as flotation solvent, Fe(III) ion was as trapping agent, pH of test solution was 7.6, the gas flow rate was 40 mL x min(-1), and the flotation time was 50 min. The complexes of TCs- Fe (III) were pre-concentrated in the [Hmim] PF6-EA layer and this was used to determine analytes by fluorescence method directly. The linear regression equation was F = 246.5c+4.32 (c: microg x 10 mL(-1)), and correlation coefficient was 0.999 1. Recoveries between 94.2% and 100.4% were achieved from surface water and sediment samples in ponder by using this method and the relative standard deviation of 5 microg x mL(-1) TCs for 5 parallel determinations was less than 3.2%. FTIR spectroscopy demonstrated that no chemical (bonding) interactions occurred between the ionic liquid and the complexes functional groups, and the ionic liquid was only solvent. The experimental result indicated that utilizing ionic liquid to float TCs in environmental sample is feasible.


Assuntos
Resíduos de Drogas/química , Espectrometria de Fluorescência , Tetraciclinas/química , Poluentes Químicos da Água/química , Antibacterianos/química , Monitoramento Ambiental , Compostos Férricos , Líquidos Iônicos , Íons , Solventes
16.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(6): 593-6, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17939392

RESUMO

OBJECTIVE: In order to investigate the positive rate of streptococcus suis type 2 and the genes of their suilysin (sly), extracellular protein (epf) and muramidasa-released protein ( mrp) and to understand the antibiotic susceptibility of S. suis type 2. METHODS: S. suis type 2, isolated from slaughtered healthy pig's tonsil in 10 county area of Guangxi, were identified by Multiplex PCR, and the genes of their sly, epf, mrp and the antimicrobial sensitivity analysis were performed. RESULTS: 1105 strains of Streptococcus including 667 strains of S. suis and 33 strains of S. suis type 2 were detected from 1179 samples. In these S. suis type 2 strains, there were 22 strains of sly + mrp + epf+ type,1 strain of sly + mrp + epf - type, 2 strains of sly - mrp + epf + type, 7 strains of sly - mrp + epf - type and 1 strain of sly - mrp - epf- type. When these strains were subjected to be tested with penicillin, eritrocina, vacocin, gentamycin, specti-nomysin, enraxacin, ciprofloxaxin, cephalothin VI, sulfadiazine sodium, cyantin, mycifradin, amikacin and achromcin, some were found to be resistant to but most strains were susceptible to cephalothin VI, penicillin and enraxacin. There were 31, 29 and 27 strains over medium sensitivity, respectively, but 28 and 27 resistant strains to amikacin and achromcin were found. CONCLUSION: The positive rate of S. suis type 2 in clinical healthy pigs was low (2.8%) and did not show obvious difference between the counties with or without a history of S. suis infection. All the isolated strains were susceptible to cephalothin VI, but most strains were virulent.


Assuntos
Epidemiologia Molecular/métodos , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus suis/genética , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Animais , Antibacterianos/farmacologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Proteínas Hemolisinas/genética , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Infecções Estreptocócicas/genética , Streptococcus suis/efeitos dos fármacos , Streptococcus suis/patogenicidade , Suínos , Doenças dos Suínos/genética
17.
J Clin Virol ; 39(4): 295-303, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17588806

RESUMO

BACKGROUND: Surveillance data for rabies in Guangxi Province in China showed that human rabies cases have gradually increased since 1996. OBJECTIVE: To evaluate the epidemiology of rabies at the molecular level and provide suggestions for effective prevention of rabies in Guangxi. STUDY DESIGN: Since 2000, 1569 brains from suspected rabid animals were collected from different areas of Guangxi. Rabies virus was isolated from 42 samples. RT-PCR was used to amplify a 455 nucleotide segment of the 3'-terminal of the N gene. The sequencing data from that segment was used for phylogenetic analysis. RESULTS: Nucleotide homology comparisons and phylogenetic tree analysis based on this sequence indicated that all the rabies virus isolates from Guangxi belonged to genotype 1 and could be divided into four groups. Groups I, II and IV included 23, 10 and 8 isolates, respectively. These had nucleotide homologies of 97.1-100%, 98.2-100% and 99.1-99.6%, respectively. Only the GXN119 strain belonged to group III. Group I had two group-specific mutations: T90N and E110D. Group II had one group-specific mutation of T42S. CONCLUSIONS: This study showed that rabies virus isolates from Guangxi have a close genetic relationship and topographical distribution.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças do Cão/epidemiologia , Epidemiologia Molecular , Vírus da Raiva/genética , Raiva/veterinária , Doenças dos Suínos/epidemiologia , Sequência de Aminoácidos , Animais , Encéfalo/virologia , Bovinos , Doenças dos Bovinos/virologia , China/epidemiologia , Doenças do Cão/virologia , Cães , Genótipo , Dados de Sequência Molecular , Mutação , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/genética , Filogenia , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/isolamento & purificação , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/virologia
18.
J Clin Microbiol ; 45(1): 255-6, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17021061

RESUMO

We describe the isolation of Laribacter hongkongensis in Hangzhou City, People's Republic of China. One strain of bacterium, named LHHZ242, had many of the same phenotypic and genotypic characteristics as Laribacter hongkongensis described in previous publications. This discovery proves that Laribacter hongkongensis is also associated with community-acquired gastroenteritis outside Hong Kong.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Gastroenterite/microbiologia , Infecções por Neisseriaceae/microbiologia , Neisseriaceae/classificação , Neisseriaceae/isolamento & purificação , China/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Fezes/microbiologia , Gastroenterite/epidemiologia , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Neisseriaceae/genética , Infecções por Neisseriaceae/epidemiologia , Fenótipo , Filogenia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
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