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2.
Zhonghua Yi Xue Za Zhi ; 99(7): 537-541, 2019 Feb 19.
Artigo em Chinês | MEDLINE | ID: mdl-30786353

RESUMO

Objective: To modify Western Ontario and McMaster University Osteoarthritis Index (WOMAC) for more accurate evaluation of patients with knee osteoarthritis in China,and its reliability and validity were measured. Methods: The WOMAC was modified through reviewing relevant literatures and practical survey.Total of 120 patients were enrolled in this study. The subjects completed the WOMAC,the modified WOMAC and Medical Outcomes Study 36-item Short Form(SF-36), and 113 of the questionnaires were valid for analysis [27 males (23.9%), 86 females (76.1%), aged (59±10) years]. Intraclass correlation coefficient and Cronbach α reliability coefficient were used to analyze the modified WOMAC's reliability; exploratory factor analysis was adopted to analyze the validity of WOMAC and the modified WOMAC; Spearman rank correlation coefficient was used to make a correlation analysis among SF-36, WOMAC and the modified WOMAC. Results: For the four dimensions: pain, stiffness, function and life quality in the modified WOMAC, the intraclass correlation coefficient values were 0.861-0.910 and Cronbach α values were 0.751-0.936. In the content validity analysis, the number of extracted common factors for the four dimensions: pain,stiffness,function and life quality in the modified WOMAC were 1,1,2 and 1 respectively. The total variance interpretation rate was 65.684%, 84.367%, 67.252% and 67.572%, respectively. In the construct validity analysis, 4 common factors were extracted for WOMAC and the modified WOMAC respectively. The total variance interpretation rate was 70.100% and 67.213%, respectively. Both WOMAC and the modified WOMAC had a significant correlation with SF-36. Conclusion: The modified WOMAC is more suitable for Chinese living habits, but it still needs to be further evaluated with larger samples.


Assuntos
Osteoartrite do Joelho , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Inquéritos e Questionários , Universidades
3.
Phys Rev Lett ; 120(20): 207204, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29864355

RESUMO

We investigate the current-induced switching of the Néel order in NiO(001)/Pt heterostructures, which is manifested electrically via the spin Hall magnetoresistance. Significant reversible changes in the longitudinal and transverse resistances are found at room temperature for a current threshold lying in the range of 10^{7} A/cm^{2}. The order-parameter switching is ascribed to the antiferromagnetic dynamics triggered by the (current-induced) antidamping torque, which orients the Néel order towards the direction of the writing current. This is in stark contrast to the case of antiferromagnets such as Mn_{2}Au and CuMnAs, where fieldlike torques induced by the Edelstein effect drive the Néel switching, therefore resulting in an orthogonal alignment between the Néel order and the writing current. Our findings can be readily generalized to other biaxial antiferromagnets, providing broad opportunities for all-electrical writing and readout in antiferromagnetic spintronics.

4.
Nat Commun ; 8(1): 449, 2017 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-28878205

RESUMO

The independent control of two magnetic electrodes and spin-coherent transport in magnetic tunnel junctions are strictly required for tunneling magnetoresistance, while junctions with only one ferromagnetic electrode exhibit tunneling anisotropic magnetoresistance dependent on the anisotropic density of states with no room temperature performance so far. Here, we report an alternative approach to obtaining tunneling anisotropic magnetoresistance in α'-FeRh-based junctions driven by the magnetic phase transition of α'-FeRh and resultantly large variation of the density of states in the vicinity of MgO tunneling barrier, referred to as phase transition tunneling anisotropic magnetoresistance. The junctions with only one α'-FeRh magnetic electrode show a magnetoresistance ratio up to 20% at room temperature. Both the polarity and magnitude of the phase transition tunneling anisotropic magnetoresistance can be modulated by interfacial engineering at the α'-FeRh/MgO interface. Besides the fundamental significance, our finding might add a different dimension to magnetic random access memory and antiferromagnet spintronics.Tunneling anisotropic magnetoresistance is promising for next generation memory devices but limited by the low efficiency and functioning temperature. Here the authors achieved 20% tunneling anisotropic magnetoresistance at room temperature in magnetic tunnel junctions with one α'-FeRh magnetic electrode.

5.
Phys Rev Lett ; 118(25): 257201, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28696748

RESUMO

We report the experimental observation of spin-orbit torque induced switching of perpendicularly magnetized Pt/Co elements in a time resolved stroboscopic experiment based on high resolution Kerr microscopy. Magnetization dynamics is induced by injecting subnanosecond current pulses into the bilayer while simultaneously applying static in-plane magnetic bias fields. Highly reproducible homogeneous switching on time scales of several tens of nanoseconds is observed. Our findings can be corroborated using micromagnetic modeling only when including a fieldlike torque term as well as the Dzyaloshinskii-Moriya interaction mediated by finite temperature.

6.
Zhonghua Wai Ke Za Zhi ; 54(8): 591-5, 2016 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-27502132

RESUMO

OBJECTIVE: To summarize the experience of totally thoracoscopic cardiac surgical (TTCS) at congenital heart diseases (CHD) treatment. METHODS: From April 2000 to March 2016, 2 543 patients with CHD underwent TTCS in Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, including 957 male and 1 586 female patients. The age ranged from 0.5 to 66.0 years with a mean age of (21±18) years. The body weight ranged from 6 to 118 kg with a mean of (49±30) kg. Patients were diagnosed with echocardiography or transesophagel echocardiography as complex or complicated CHD which was unsuitable for percutaneous procedure. Surgical procedures were performed through 3 holes inserted at the right chest wall, and catheters were placed in the right femoral artery and vein to set up cardiopulmonary bypass.The ascending aorta was cross-clamped with long tailor-made forceps and the myocardium was protected by coronary perfusion with cold crystalloid(blood)cardioplegia. There were 787 cases (from January 2013 to December 2015) were selected to compare with 710 cases underwent conventional thoracotomy over the same period. Statistical analysis was performed by t test, t' test, rank-sum test, χ(2) test and Fisher exact test, respectively. RESULTS: The total death rate and the major complication rate of the operation were 0.35% (9/2 543) and 2.28% (58/2 543), respectively. All patients were followed up 1 to 190 months and the average follow-up time was (75±34) months. No residual shunt or obvious mitral/tricuspid regurgitation was observed, and the patients gained better cardiac function as level Ⅰ to Ⅱ (New York Heart Association classification). There was no significant difference in aorta clamp time, ICU stay, hospital cost, and surgical fatality rate between 787 patients underwent TTCS and 710 conventional thoracotomy. The cardiopulmonary bypass time ((31±20) minuets vs. (40±17) minuets, t'=9.407, P=0.001), operation time ((91±27) minuets vs. ( 102±64) minuets, t'=4.251, P=0.000), hospital stay ((5.3±2.2) d vs. (13.0±4.0) d, t'=45.463, P=0.000), postoperative drainage (M(QR): 33(17) ml vs. 121(53) ml, T=2.632, P=0.000) and major complications (7/787 vs. 23/710, χ(2)=10.49, P=0.001) were significantly reduced and no sternal deformation occurrence (0 vs. 192/710, χ(2)=244.10, P=0.000) in TTCS group. While the cost was higher in TTCS group ((24 000±400) yuan vs. (20 000±400) yuan, t=19.320, P=0.000). CONCLUSION: TTCS is feasible, safe, and minimal invasive for patients with CHD, resulting in quick recovery and good median-long term outcomes.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Cardiopatias Congênitas/cirurgia , Toracoscopia/métodos , Toracotomia , Adolescente , Adulto , Criança , Pré-Escolar , Ecocardiografia , Feminino , Artéria Femoral , Parada Cardíaca Induzida , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Resultado do Tratamento , Adulto Jovem
7.
Nanoscale ; 8(29): 13893-7, 2016 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26952735

RESUMO

PtCo nanoparticles, having two atomic layers of stabilized Pt skin, supported on carbon black (Pt2AL-PtCo/C), exhibited superlative mass activity for the CO-tolerant hydrogen oxidation reaction (HOR), together with high robustness with respect to air exposure, as a novel anode catalyst in reformate gas-based polymer electrolyte fuel cells. The high area-specific HOR activity and CO tolerance are consistent with DFT calculations.

8.
Genet Mol Res ; 14(4): 12022-9, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26505349

RESUMO

We investigated the effects of BCL2 transfection on the cell cycle and proliferation of GES-1 cells. A pcDNA3-BCL2 plasmid was used to transfect GES-1 cell line human gastric epithelial cells. Clones were obtained by G418 screening. BCL2-positive cells were identified by fluorescence immunohistochemistry. The pcDNA3-BCL2 vectors carrying the NeoR gene were transfected into GES-1 cells, while the empty plasmid was transfected into the same cells as controls. BCL2-positive clones were screened by neomycin 418 (G418). Flow cytometry was used to detect the cell cycle. Hematoxylin and eosin (H&E) staining revealed morphological changes, and the effects of BCL2 transfection on cell proliferation were analyzed by cell counting and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The plasmid pcDNA3-BCL2 was identified by restriction enzyme digestion. Different degrees of BCL2 gene expression were detected in all seven clones. BCL2 was expressed mainly in the cytoplasm and the nuclear membrane. There were significantly more S-phase cells in the transfection group than in the controls. The morphology did not change after H&E staining. Cell growth was faster than in the controls after transfection for 6 days. At 24, 48, and 72 h after transfection, the A values were 4.15 ± 0.31, 5.98 ± 0.56, and 8.94 ± 0.79; those of the controls were 3.01 ± 0.20, 4.76 ± 0.52, and 7.69 ± 0.84; there was a significant difference between the two groups (P < 0.05). BCL2 transfection increased GES-1 cells in the S phase; the GES-1 cells were stable and BCL2 expression was high, which promoted cell proliferation.


Assuntos
Ciclo Celular , Proliferação de Células , Proteínas Proto-Oncogênicas c-bcl-2/genética , Linhagem Celular Tumoral , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transfecção
9.
Genet Mol Res ; 14(1): 898-905, 2015 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-25730028

RESUMO

We investigated the clinical efficacy of adoptive cytokine-induced killer (CIK) cell and dendritic cell (DC) therapy plus intensity-modulated radiation therapy (IMRT) for treating elderly patients with esophageal carcinoma (EC). In total, 68 elderly patients with EC were randomized to receive IMRT plus DC-CIK immunotherapy (study group, N = 34) or IMRT only (control group, N = 34). Clinical efficacy, immune function, toxicity and side effects, and life quality were evaluated after treatment. The efficacy rate was significantly higher in the study group than in the control group. Remarkable increases were noted for quality of life and immune function in the study group relative to the control group. Regarding toxicity and side effects, compared with the control group, the study group displayed a higher fever rate, a lower incidence rate of bone marrow suppression, and a similar rate of digestive tract reactions. DC-CIK immunotherapy plus IMRT exhibited better short-term efficacy than IMRT alone in elderly patients with EC. The therapy could improve patients'quality of life and immune function, decrease bone marrow suppression, and lengthen survival time.


Assuntos
Carcinoma/radioterapia , Terapia Baseada em Transplante de Células e Tecidos , Células Matadoras Induzidas por Citocinas/transplante , Neoplasias Esofágicas/radioterapia , Idoso , Carcinoma/imunologia , Carcinoma/patologia , Células Matadoras Induzidas por Citocinas/imunologia , Células Dendríticas/imunologia , Células Dendríticas/transplante , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/patologia , Feminino , Humanos , Imunoterapia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Radioterapia de Intensidade Modulada/efeitos adversos
10.
Genet Mol Res ; 13(2): 3100-7, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24782167

RESUMO

We aimed to assess the role of polymorphisms of the XRCC1 Arg194Trp, XRCC1 Arg399Gln, ERCC5 His1104Asp, and ERCC5 His46His genes on clinical outcomes of advanced non-small cell lung cancer (NSCLC) patients receiving platinum-based chemotherapy regimens. A total of 378 NSCLC patients were asked to participate within 1 month after diagnosis between January 2005 and January 2006, and they were followed up until November 2011. Genomic DNA of the four genes was extracted using the Qiagen Blood Kit. Results showed that individuals with XRCC1 399A/A and ERCC5 46T/T genotypes were more likely to show positive responses to chemotherapy, with odds ratio (OR) = 2.27 and 95% confidence interval (CI) = 1.64-6.97, and OR = 1.90, CI = 1.10-3.28, respectively. The XRCC1 399A/A genotype was significantly associated with longer progression-free survival (PFS) and overall survival (OS) rates, and the hazard ratios (HRs) (95%CI) were 0.48 (0.25-0.88) and 0.51 (0.26-0.98), respectively. Similarly, NSCLC patients carrying the ERCC5 46T/T genotype were more likely to show increased PFS and OS, with HRs (95%CI) of 0.47 (0.22-0.82) and 0.52 (0.31-0.96), respectively. In conclusion, our study indicated that XRCC1 Arg399Gln and ERCC5 His46His might significantly influence the response to chemotherapy, and the two genetic polymorphisms are suggested to be routinely detected to determine NSCLC patients that are more likely to benefit from chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Reparo do DNA/genética , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Platina/administração & dosagem , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
11.
Genet Mol Res ; 13(1): 228-36, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24446315

RESUMO

Individual differences in chemosensitivity and clinical outcome of non-small-cell lung carcinoma (NSCLC) patients can be influenced by host-inherited factors. We investigated the impact of XRCC1 Arg194Trp, XRCC1 Arg280His, XRCC1 Arg399Gln, XPD Arg156Arg, XPD Asp312Asn, XPD Asp711Asp, and XPD Lys751Gln gene polymorphisms on treatment efficacy in 375 NSCLC patients on platinum-based chemotherapy. We also examined progression-free survival and overall survival. The gene polymorphisms were analyzed by duplex PCR. The patients with XRCC1 399A/A had a significantly better response to chemotherapy. Individuals with XPD 711 Asp and XPD 312 Asn alleles responded poorly to chemotherapy when compared with the wide-type genotype. The adjusted hazard ratio (HR) in the Cox regression model was calculated. The XRCC1 399A/A polymorphism was associated with better progression free survival and overall survival of NSCLC patients (HR=0.61 and 0.55). On the other hand, the XPD 711 Asp allele was associated with poorer progression free survival and overall survival compared to the C/C genotype, with HRs of 1.89 and 1.90. The XPD 312 Asn allele was found to be associated with non-significantly reduced survival of NSCLC patients (HR = 1.73). In conclusion, we found the polymorphisms of XRCC1 and XPD to be related to the efficacy of platinum-based chemotherapy in NSCLC patients. This information should aid in therapeutic decisions for individualized therapy in NSCLC cases.


Assuntos
Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Proteína Grupo D do Xeroderma Pigmentoso/genética , Idoso , Alelos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Farmacogenética , Resultado do Tratamento , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
12.
Lett Appl Microbiol ; 55(2): 128-34, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22691226

RESUMO

AIMS: To investigate the effects of nisin on lactobacilli contamination of yeast during ethanol fermentation and to determine the appropriate concentration required to control the growth of selected lactobacilli in a YP/glucose media fermentation model. METHODS AND RESULTS: The lowest concentration of nisin tested (5 IU ml(-1) ) effectively controlled the contamination of YP/glucose media with 10(6) CFU ml(-1) lactobacilli. Lactic acid yield decreased from 5.0 to 2. 0 g l(-1) and potential ethanol yield losses owing to the growth and metabolism of Lactobacillus plantarum and Lactobacillus brevis were reduced by 11 and 7.8%, respectively. Approximately, equal concentrations of lactic acid were produced by Lact. plantarum and Lact. brevis in the presence of 5 and 2 IU ml(-1) nisin, respectively, thus demonstrating the relatively higher nisin sensitivity of Lact. brevis for the strains in this study. No differences were observed in the final ethanol concentrations produced by yeast in the absence of bacteria at any of the nisin concentrations tested. CONCLUSIONS: Metabolism of contaminating bacteria was reduced in the presence of 5 IU ml(-1) nisin, resulting in reduced lactic acid production and increased ethanol production by the yeast. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriocins represent an alternative to the use of antibiotics for the control of bacterial contamination in fuel ethanol plants and may be important in preventing the emergence of antibiotic-resistant contaminating strains.


Assuntos
Bacteriocinas/farmacologia , Etanol/metabolismo , Microbiologia Industrial , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus/efeitos dos fármacos , Nisina/farmacologia , Saccharomyces cerevisiae/metabolismo , Fermentação , Ácido Láctico/biossíntese , Ácido Láctico/metabolismo , Ácido Láctico/farmacologia , Lactobacillus/crescimento & desenvolvimento , Lactobacillus plantarum/crescimento & desenvolvimento
13.
Prikl Biokhim Mikrobiol ; 48(2): 243-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22586919

RESUMO

The gene mel1, encoding alpha-galactosidase in Schizosaccharomyces pombe, and the gene bgl2, encoding and beta-glucosidase in Trichoderma reesei, were isolated and co-expressed in the industrial ethanol-producing strain of Saccharomyces cerevisiae. The resulting strains were able to grow on cellobiose and melibiose through simultaneous production of sufficient extracellular alpha-galactosidase and beta-glucosidase activity. Under aerobic conditions, the growth rate of the recombinant strain GC 1 co-expressing 2 genes could achieve 0.29 OD600 h(-1) and a biomass yield up to 7.8 g l(-1) dry cell weight on medium containing 10.0 g l(-1) cellobiose and 10.0 g l(-1) melibiose as sole carbohydrate source. Meanwhile, the new strain of S. cerevisiae CG 1 demonstrated the ability to directly produce ethanol from microcrystalline cellulose during simultaneous saccharification and fermentation process. Approximately 36.5 g l(-1) ethanol was produced from 100 g of cellulose supplied with 5 g l(-1) melibose within 60 h. The yield (g of ethanol produced/g of carbohydrate consumed) was 0.44 g/g, which corresponds to 88.0% of the theoretical yield.


Assuntos
Celobiose/metabolismo , Etanol/metabolismo , Proteínas Fúngicas/metabolismo , Microbiologia Industrial , Melibiose/metabolismo , Saccharomyces cerevisiae/genética , alfa-Galactosidase/metabolismo , beta-Glucosidase/metabolismo , Fermentação , Proteínas Fúngicas/genética , Engenharia Genética/métodos , Saccharomyces cerevisiae/enzimologia , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Trichoderma/enzimologia , Trichoderma/genética , alfa-Galactosidase/genética , beta-Glucosidase/genética
14.
J Fluoresc ; 21(1): 17-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20593228

RESUMO

CdSe/CdS quantum dots (QDs) capped with L-cysteine can provide an effective platform for the interactions with bovine serum albumin (BSA). In this study, absorption and fluorescence (FL) spectroscopy were used to study the binding reactions of QDs with BSA, respectively. The binding constant (≈10(4) M(-1)) from FL quenching method matches well with that determined from the absorption spectral changes. The modified Stern-Volmer quenching constant (5.23 × 10(4), 5.22 × 10(4), and 4.90 × 10(4) M(-1)) and the binding sites (≈1) at different temperatures (304 K, 309 K, and 314 K) and corresponding thermodynamic parameters were calculated (∆G < 0, ∆H < 0, and ∆S < 0). The results show the quenching constant is inversely correlated with temperature. It indicates the quenching mechanism is the static quenching in nature rather than dynamic quenching. The negative values of free energy (∆G < 0) suggest that the binding process is spontaneous, ∆H < 0 and ∆S < 0 suggest that the binding of QDs to BSA is enthalpy-driven. The enthalpy and entropy changes for the formation of ground state complex depend on the capping agent of QDs and the protein types. Furthermore, the reaction forces were discussed between QDs and BSA, and the results show hydrogen bonds and van der Waals interactions play a major role in the binding reaction.


Assuntos
Compostos de Cádmio/química , Cisteína/química , Pontos Quânticos , Compostos de Selênio/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência/métodos , Sulfetos/química , Termodinâmica
15.
J Int Med Res ; 38(2): 593-601, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20515572

RESUMO

T-lymphocyte subpopulations and B7-H1/programmed death-1 (PD-1) positive lymphocytes infiltrating nasal polyps were evaluated in 17 patients with chronic sinusitis with nasal polyposis. Peripheral blood samples were also obtained from the patients and from 11 healthy controls. The CD4(+), CD8(+), CD3(+), CD19(+), B7-H1(+) and PD-1(+) lymphocyte populations were measured using flow cytometry. Lymphocytes from nasal polyps had significantly fewer CD4(+) but significantly more CD8(+) T-cells compared with lymphocytes from the peripheral blood of patients and controls. The percentages of CD19(+)/B7-H1(+) B-cells and of CD3(+)/PD-1(+) T-cells were significantly higher in the nasal polyp samples than in those from peripheral blood of patients and controls. Changes in the T-lymphocyte subpopulations and in the up-regulation of B7-H1 and PD-1 in lymphocytes infiltrating nasal polyps may be involved in the development of the chronic inflammation associated with nasal polyposis.


Assuntos
Antígenos CD/imunologia , Linfócitos B/imunologia , Pólipos Nasais/imunologia , Subpopulações de Linfócitos T/imunologia , Antígeno B7-H1 , Estudos de Casos e Controles , Doença Crônica , Citometria de Fluxo , Humanos , Estudos Prospectivos , Sinusite/imunologia
16.
J Thromb Haemost ; 8(8): 1773-83, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20492477

RESUMO

BACKGROUND: Hemophilia B is an X-linked inherited disorder caused by the lack of functional factor IX (FIX). Currently, treatment of hemophilia B is performed by intravenous infusion of plasma-derived or recombinant FIX. OBJECTIVE: In an effort to reduce factor usage and cost, we investigated the potential use of FIX variants with enhanced specific clotting activity. METHODS: Seven recombinant FIX variants using alanine replacement were generated and assayed for their activity in vitro and in vivo. RESULTS: One variant containing three substitutions (V86A/E277A/R338A, FIX-Triple) exhibited 13-fold higher specific clotting activity and a 10-fold increased affinity for human FVIIIa compared with FIX-wild-type (FIX-WT) and was thus investigated systematically in vivo. Liver-specific FIX-Triple gene expression following hydrodynamic plasmid delivery revealed a 3.5-fold higher specific clotting activity compared with FIX-WT. Human FIX-Triple and FIX-WT knock-in mice were generated and it was confirmed that FIX-Triple has 7-fold higher specific clotting activity than FIX-WT under normal physiological conditions. Protein infusion of FIX-Triple into hemophilia B mice resulted in greater improvement of hemostasis than that achieved with FIX-WT. Moreover, tail-vein administration of a serotype 8 recombinant Adeno-associated vector (AAV8) expressing either FIX-WT or FIX-Triple in hemophilia B mice demonstrated a 7-fold higher specific clotting activity of FIX-Triple than FIX-WT. CONCLUSIONS: Our results indicate that the FIX-Triple variant exhibits significantly enhanced clotting activity relative to FIX-WT due to tighter binding to FVIIIa, as demonstrated both in vitro and in vivo. Therefore, FIX-Triple is a good candidate for further evaluation in protein replacement therapy as well as gene-based therapeutic strategies.


Assuntos
Fator IX/química , Animais , Coagulação Sanguínea , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Fator VIIIa/genética , Fator X/genética , Variação Genética , Hemofilia B/genética , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Knockout , Mutagênese , Tempo de Tromboplastina Parcial , Proteínas Recombinantes/química , Ressonância de Plasmônio de Superfície
17.
J Thromb Haemost ; 8(1): 194-201, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19874473

RESUMO

BACKGROUND: Activation of vascular endothelial cells plays an important role in atherogenesis and plaque instability. Recent research has demonstrated that late-stage inhibition of plaque angiogenesis by angiostatin (kringle 1-4) reduces macrophage accumulation and slows the progression of advanced atherosclerosis. Kringle 1-5 (K(1-5)) is a variant of angiostatin that contains the first five kringle domains of plasminogen. OBJECTIVE: To investigate whether K(1-5) has an inhibitory effect on early-stage atherosclerosis, using the apolipoprotein E (ApoE)-deficient mouse model and a carotid artery ligation model. METHODS: ApoE-deficient mice received K(1-5) treatment for 4 weeks, and the severity of aortic atherosclerosis was measured. In the ligation model, the left common carotid arteries of C57BL/6 mice were ligated near the carotid bifurcation, and the mice received K(1-5) for 4 weeks. Human umbilical vein endothelial cells were pretreated with K(1-5) before tumor necrosis factor-alpha (TNF-alpha) treatment to explore the anti-inflammatory effect of K(1-5). RESULTS: The areas of the lesion in the aortas of ApoE-deficient mice that received K(1-5) treatment were notably decreased, and the formation of carotid neointima in the C57BL/6 mice was decreased by treatment with K(1-5). Expression of TNF-alpha-induced intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 was inhibited by K(1-5) treatment, possibly via downregulation of translocation of nuclear factor-kappaB and expression of reactive oxygen species. CONCLUSIONS: K(1-5) reduced atherosclerosis and neointima formation in mice, possibly through inhibition of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression in endothelial cells.


Assuntos
Aorta/metabolismo , Aterosclerose/prevenção & controle , Artérias Carótidas/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/prevenção & controle , Fragmentos de Peptídeos/metabolismo , Plasminogênio/metabolismo , Transdução de Sinais , Túnica Íntima/metabolismo , Animais , Aorta/imunologia , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Artérias Carótidas/imunologia , Artérias Carótidas/patologia , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Humanos , Hiperplasia , Proteínas I-kappa B/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Plasminogênio/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Túnica Íntima/imunologia , Túnica Íntima/patologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
18.
J Thromb Haemost ; 6(10): 1685-92, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18647232

RESUMO

BACKGROUND: Dextromethorphan (DM) is reported to reduce the inflammation-mediated degeneration of dopaminergic neurons. OBJECTIVE: The goal of this study was to test if DM can improve the endothelial dysfunction and inflammatory markers in heavy smokers. PATIENTS AND METHODS: Forty habitual smoking healthy male volunteers (mean age, 31.5 +/- 1.4 years) were randomly given either DM (120 mg day(-1)) or a placebo for 6 months. We determined endothelial function using the brachial artery diameter changes in flow-mediated dilatation (FMD) and measured their inflammatory and oxidative markers. A sex-and-age matched non-smoking group (n = 20) was compared as normal parameters. RESULTS: Habitual smokers showed impaired baseline endothelial function in FMD (smoking vs. non-smoking: 6.3 +/- 1.8 vs. 10.2 +/- 2.3% respectively, P < 0.01). Without change in smoking behavior, lipid and metabolic parameters, a significant increase in FMD was found in the DM-treated group (32%), accompanied by a decrease in high-sensitivity C-reactive protein (hs-CRP), phospholipase A(2), matrix metalloproteinase-3, interleukin 6 (IL-6) and tumor necrosis factor-alpha receptor II (TNF-alpha RII) (all P < 0.05), but unchanged in von Willebrand factor (VWF)and plasminogen activator inhibitor-1 (PAI-1). An increase in plasma glutathione peroxidase and a decrease in spot urinary excretion of 8-epi-prostaglandin F(2a) were found in DM-treated smokers. CONCLUSIONS: Our study suggests that a 6-month treatment with DM can improve endothelial function and attenuate vascular oxidative stress and inflammation markers in habitual smokers.


Assuntos
Dextrometorfano/administração & dosagem , Endotélio Vascular/efeitos dos fármacos , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Fumar/tratamento farmacológico , Adulto , Método Duplo-Cego , Humanos , Masculino , Resultado do Tratamento , Vasodilatação/efeitos dos fármacos , Adulto Jovem
19.
J Thromb Haemost ; 4(5): 1023-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16689754

RESUMO

BACKGROUND: Oxidation of low density lipoproteins is an initial step of atherogenesis that generates pro-inflammatory phospholipids, including platelet-activating factor (PAF). PAF is degraded by PAF-acetylhydrolase (PAF-AH), which has been postulated to be a risk factor for myocardial infarction (MI). The role of PAF-AH for the onset of premature MI is unclear. METHODS: Polymorphisms located in putatively functional regions were investigated in a cohort of patients having premature MI onset prior to 46 years of age (n = 200) and a sex-age-matched control group (n = 200). The activity of PAF-AH and coronary angiograms were evaluated for the severity of coronary atherosclerosis. RESULTS: The V allele of A379V (exon 11) polymorphism on PAF-AH gene was more frequent in patients with premature MI (P = 0.001). This V allele polymorphism was also associated with a lower activity of plasma PAF-AH and a more complex coronary atherosclerosis (p Trends <0.05). Multiple logistic regression analysis showed that this polymorphism was an independent risk factor (Odds Ratio [OR] 1.66, 95% CI 1.14.1 to 5.80, P = 0.008) as well as smoking (OR 3.72, 95% CI 1.77 to 9.28, P = 0.001), diabetes mellitus (OR 2.25, 95% CI 1.40 to 5.32, P = 0.007) and hypertension (OR 1.88, 95% CI 1.25 to 5.36, P = 0.003) for the onset of premature MI. CONCLUSION: We conclude that a functional and significant association between the A379V polymorphism on exon 11 of PAF-AH gene and premature MI exists in this Taiwanese population. This polymorphism is significantly associated with the PAF-AH activity and the severity of coronary atherosclerosis.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Éxons , Infarto do Miocárdio/genética , Polimorfismo Genético , Adulto , Idade de Início , Estudos de Coortes , Feminino , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/enzimologia , Fosfolipases A/metabolismo , Fatores de Risco
20.
Environ Monit Assess ; 92(1-3): 5-24, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15038532

RESUMO

Measurements of aerosols were made in 2001 and 2002 at Dunhuang (40 degrees 00'N, 94 degrees 30'E), China to understand the nature of atmospheric particles over the desert areas in the Asian continent. Balloon-borne measurements with an optical particle counter suggested that particle size and concentration had noticeable peaks in super micron size range not only in the boundary mixing layer but also in the free troposphere. Super-micron particle concentration largely decreased in the mid tropopause (from 5 to 10 km; above sea level, a.s.l.). Lidar measurements made during August 2002 at Dunhuang suggested the possibility that mixing of dust particles occurred from near the ground to about 6 km even under calm weather conditions, and a large depolarization ratio of particulate matter was found in the aerosol layer. The top of the aerosol layer was found at heights of nearly 6 km (a.s.l.). It is strongly suggested that nonspherical dust particles (Kosa particles) frequently diffused in the free atmosphere over the Taklamakan desert through small-scale turbulences and are possible sources of dust particles of weak Kosa events that have been identified in the free troposphere not only in spring but also in summer over Japanese archipelago. Electron microscopic experiments of the particles collected in the free troposphere confirmed that coarse and nonspherical particles observed by the mineral particle were major components of coarse mode (diameter larger than 1 microm) below about 5 km over Dunhuang, China.


Assuntos
Poluentes Atmosféricos/análise , Poeira , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Aerossóis , Movimentos do Ar , Óptica e Fotônica , Tamanho da Partícula , Estações do Ano
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