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排序方式: 共有3190条查询结果,搜索用时 31 毫秒
41.
Fabiana Miraglia Minekazo Matsuo Zenaide Maria Morais Odir Antonio Dellagostin Fabiana Kömmling Seixas Julio César Freitas Rudy Hartskeerl Luisa Zanolli Moreno Bárbara Letícia Costa Gisele Oliveira Souza Silvio Arruda Vasconcellos Andrea Micke Moreno 《Diagnostic microbiology and infectious disease》2013
Leptospira interrogans serogroup Icterohaemorrhagiae is the major serogroup infecting humans worldwide, and rodents and dogs are the most significant transmission sources in urban environments. Knowledge of the prevalent serovars and their maintenance hosts is essential to understand the epidemiology of leptospirosis. In this study, 20 Leptospira isolates were evaluated by pulsed-field gel electrophoresis (PFGE), variable number tandem-repeat analysis (VNTR), serotyping, and determination of antimicrobial resistance profile. Isolates, originated from bovine, canine, human, and rodent sources, were characterized by microscopic agglutination test with polyclonal and monoclonal antibodies and were identified as L. interrogans serogroup Icterohaemorrhagiae serovar Copenhageni. MICs of antimicrobials often used in veterinary medicine were determined by broth microdilution test. Most of tested antibiotics were effective against isolates, including penicillin, ampicillin, and ceftiofur. Higher MIC variability was observed for fluoroquinolones and neomycin; all isolates were resistant to trimethoprim/sulfamethoxazole and sulphadimethoxine. Isolates were genotyped by PFGE and VNTR; both techniques were unable to discriminate between serovars Copenhageni and Icterohaemorrhagiae, as expected. PFGE clustered all isolates in 1 pulsotype, indicating that these serovars can be transmitted between species and that bovine, rodent, and dogs can maintain them in the environment endangering the human population. 相似文献
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Inflammatory cytokines alter the hemostatic balance of endothelial cells (ECs). Alternatively spliced human tissue factor (asHTF), a soluble isoform of tissue factor (TF), has recently been detected in ECs, possibly contributing to procoagulability. Agonists regulating asHTF expression and release are yet unknown. This study examines the effect of TNF-alpha and IL-6 on the endothelial expression of both TF variants and delineates the impact of asHTF on the procoagulability of extracellular fluids. asHTF and TF mRNA were assessed by real-time PCR, and asHTF, TF, and tissue factor pathway inhibitor (TFPI) proteins by Western blot and fluorescence microscopy before and after stimulation with TNF-alpha (10 ng/mL) or IL-6 (10 ng/L). The procoagulability of cell supernatant was analyzed by a chromogenic assay with or without phospholipid vesicles. We found asHTF mRNA to be maximally increased 10 minutes after TNF-alpha and 40 minutes after IL-6 treatment (asHTF/GAPDH ratio 0.0223+/-0.0069 versus 0.0012+/-0.0006 for control, P<0.001 and 0.0022+/-0.0004 versus 0.0012+/-0.0007, P<0.05, respectively). Not only was asHTF increased, but also TFPI decreased after cytokine treatment. asHTF was found in the supernatant as early as 5 hours after TNF-alpha stimulation, supporting factor Xa generation after relipidation (6.55+/-1.13 U versus 2.99+/-0.59 U in control supernatant, P<0.00001). Removal of asHTF from supernatants by immunoprecipitation diminished its procoagulability to baseline. The soluble TF isoform expressed and released from ECs in response to inflammatory cytokines becomes procoagulant in the presence of phospholipids. Thus, asHTF released from ECs is a marker for and a contributor to imbalanced hemostasis. 相似文献
46.
Salvatore De Rosa Francesca Eposito Cristina Carella Antonio Strangio Giuseppe Ammirati Jolanda Sabatino Fabio Giovanni Abbate Claudio Iaconetti Vincenzo Liguori Valerio Pergola Alberto Polimeni Silvio Coletta Clarice Gareri Bruno Trimarco Giuseppe Stabile Antonio Curcio Ciro Indolfi Antonio Rapacciuolo 《European journal of heart failure》2018,20(6):1000-1010
Aims
Circulating levels of microRNAs (miRNAs) are emergent promising biomarkers for cardiovascular disease. Altered expression of miRNAs has been related to heart failure (HF) and cardiac remodelling. We measured the concentration gradients across the coronary circulation to assess their usefulness to diagnose HF of different aetiologies.Methods and results
Circulating miRNAs were measured in plasma samples simultaneously obtained from the aorta and the coronary venous sinus in patients with non‐ischaemic HF (NICM‐HF, n = 23) ischaemic HF (ICM‐HF, n = 41), and in control patients (n = 11). A differential modulation of circulating levels of miR‐423, ‐34a, ‐21‐3p, ‐126, ‐199 and ‐30a was found across the aetiology groups. Interestingly, a positive transcoronary gradient was found for miR‐423 (P < 0.001) and miR‐34a (P < 0.001) only in the ICM‐HF group. On the contrary, a positive gradient was found for miR‐21‐3p (P < 0.001) and miR‐30a (P = 0.030) only in the NICM‐HF group. Finally, no significant variations were observed in the transcoronary gradient of miR‐126 or miR‐199.Conclusions
The present findings suggest that circulating levels of miRNAs are differentially expressed in patients with HF of different aetiologies. The presence of a transcoronary concentration gradient suggests a selective release of miRNAs by the failing heart into the coronary circulation. The presence of aetiology‐specific transcoronary concentration gradients in HF patients might provide important information to better understand their role in HF, and suggests they could be useful biomarkers to distinguish HF of different aetiologies.47.
de Andrade SC de Carvalho RF Soares AS de Abreu Freitas RP de Medeiros Guerra LM Vilar MJ 《Rheumatology international》2008,29(2):147-152
The aim of this study was to evaluate the effectiveness of aerobic exercise in water pool compared with aerobic exercise performed
in sea by women with fibromyalgia (FM). A total of 46 patients were randomly allocated into two groups: pool group (23 patients)
and sea group (23 patients) that performed the same aerobic exercise program. Patients were evaluated baseline and after 12 weeks
using: VAS, number of tender points, FIQ, SF-36, PSQI, and BDI. Both groups improved significantly in post-treatment for all
the evaluated variables. There were no significant differences between two groups, except for BDI (F = 2.418, P < 0.0001). Aerobic exercise program performed in water (pool or sea) was effective for patients with FM. However, sea water
exercises have been shown to bring more advantages related to emotional aspects. Then, exercise performed sea water (thalassotherapy)
is an option for effective treatment with low cost for patients with FM. 相似文献
48.
Antoniak S Boltzen U Riad A Kallwellis-Opara A Rohde M Dörner A Tschöpe C Noutsias M Pauschinger M Schultheiss HP Rauch U 《Journal of molecular and cellular cardiology》2008,45(1):118-126
We investigated the effects of viral infection on Tissue Factor (TF) expression and activity in mice within the myocardium to understand increased thrombosis during myocarditis. Mice were infected with coxsackie virus B3 (CVB3) and the hearts were collected at day 4, 8 and 28 post infection (p.i.). Myocardial TF expression and cellular activity as well as plasma activity were analyzed from CVB3 infected mice by Western blot, chromogenic Factor Xa generation assay, in situ staining for active TF and immunohistochemistry. In addition to TF expression, hemodynamic parameters were measured during the time course of infection. Furthermore, we analyzed myocardial tissues from patients with suspected inflammatory cardiomyopathy. TF protein expression was maximally 5-fold elevated 8 days p.i. in mice and remained increased on day 28 p.i. (P < 0.001 vs. non-infected controls). Alterations in TF expression were associated with fibrin deposits within the myocardium. The TF pathway inhibitor protein expression in the myocardium was not altered during myocarditis. Active cellular TF co-localized with CD3 positive cells and VCAM-1 positive endothelial cells in the myocardium. The TF expression was positively correlated with the amount of infiltrating CD3 and Mac3 positive cells (Spearman-Rho ρ = 0.749 P < 0.0001 for CD3+ and ρ = 0.775 P < 0.0001 for Mac3+; N = 35). Increased myocardial TF expression was associated with a 2-fold elevated plasma activity (P < 0.05 vs. non-infected controls). In the human hearts, the TF expression correlated postively with an endothelial cell activation marker (ρ = 0.523 P < 0.0001 for CD62E; N = 54). Viral myocarditis is a hypercoagulative state which is associated with increased myocardial TF expression and activity. Upregulation of TF contributes to a systemic activation of the coagulation cascade. 相似文献
49.
Rizzi N Liu N Napolitano C Nori A Turcato F Colombi B Bicciato S Arcelli D Spedito A Scelsi M Villani L Esposito G Boncompagni S Protasi F Volpe P Priori SG 《Circulation research》2008,103(3):298-306
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmogenic disorder characterized by life threatening arrhythmias elicited by physical and emotional stress in young individuals. The recessive form of CPVT is associated with mutation in the cardiac calsequestrin gene (CASQ2). We engineered and characterized a homozygous CASQ2(R33Q/R33Q) mouse model that closely mimics the clinical phenotype of CPVT patients. CASQ2(R33Q/R33Q) mice develop bidirectional VT on exposure to environmental stress whereas CASQ2(R33Q/R33Q) myocytes show reduction of the sarcoplasmic reticulum (SR) calcium content, adrenergically mediated delayed (DADs) and early (EADs) afterdepolarizations leading to triggered activity. Furthermore triadin, junctin, and CASQ2-R33Q proteins are significantly decreased in knock-in mice despite normal levels of mRNA, whereas the ryanodine receptor (RyR2), calreticulin, phospholamban, and SERCA2a-ATPase are not changed. Trypsin digestion studies show increased susceptibility to proteolysis of mutant CASQ2. Despite normal histology, CASQ2(R33Q/R33Q) hearts display ultrastructural changes such as disarray of junctional electron-dense material, referable to CASQ2 polymers, dilatation of junctional SR, yet normal total SR volume. Based on the foregoings, we propose that the phenotype of the CASQ2(R33Q/R33Q) CPVT mouse model is portrayed by an unexpected set of abnormalities including (1) reduced CASQ2 content, possibly attributable to increased degradation of CASQ2-R33Q, (2) reduction of SR calcium content, (3) dilatation of junctional SR, and (4) impaired clustering of mutant CASQ2. 相似文献
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