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91.
In small arteries, a chronic blood flow reduction leads to inward hypotrophic remodeling, while a chronic blood flow elevation induces outward hypertrophic remodeling. The RhoA/Rho kinase system was shown to be modulated by shear stress, and to be involved in other kinds of vascular remodeling. The aim of this study was to investigate the role of RhoA/Rho kinase in flow-related small artery remodeling. Rat mesenteric small arteries were subjected to flow-modifying surgery. After 1, 2, 4, 16, and 32 days, the animals were sacrificed and small arteries were harvested. Messenger RNA was isolated and amplified. Using cDNA microarray analysis, the differential expression of >14,000 genes was analyzed, part of which was confirmed by RT-PCR. In vivo treatment with fasudil (3 mg/kg/day s.c.) was used to test the effect of Rho kinase inhibition. The main findings are that: (1) blood flow alteration modified the expression of approximately 5% of the genes by >2-fold, (2) flow reduction downregulated many RhoA-related cytoskeletal markers of smooth muscle cell phenotype, (3) many RhoA-related genes were rapidly (<1 day) regulated and (4) fasudil treatment potentiated the inward hypotrophic remodeling in response to chronically reduced flow. These results indicate the importance of the RhoA/Rho kinase system in flow-related small artery remodeling.  相似文献   
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Recent advances have enabled 3-dimensional reconstructions of biological structures in vivo, ranging in size and complexity from single proteins to multicellular structures. In particular, tomography and confocal microscopy have been exploited to capture detailed 3-dimensional conformations of membranes in cellular processes ranging from viral budding and organelle maintenance to phagocytosis. Despite the wealth of membrane structures available, there is as yet no generic, quantitative method for their interpretation. We propose that by modeling these observed biomembrane shapes as fluid lipid bilayers in mechanical equilibrium, the externally applied forces as well as the pressure, tension, and spontaneous curvature can be computed directly from the shape alone. To illustrate the potential power of this technique, we apply an axial force with optical tweezers to vesicles and explicitly demonstrate that the applied force is equal to the force computed from the membrane conformation.  相似文献   
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The eradication of inhibitory antibodies in patients with haemophilia A can be accomplished by frequent administration of high or intermediate doses of factor VIII (FVIII), so-called immune tolerance induction (ITI). This study monitored the distribution of IgG subclasses of anti-FVIII antibodies during ITI. FVIII-specific antibodies of subclass IgG1 were detected in all inhibitor patients tested, anti-FVIII IgG4 in 16, IgG2 in 10 and IgG3 in one of 20 patients analysed. Levels of anti-FVIII IgG1 and IgG4 correlated well with inhibitor titres as measured by Bethesda assay. In low-titre inhibitor patients, anti-FVIII antibodies consisted primarily of subclass IgG1 whereas, anti-FVIII antibodies of subclass IgG4 were more prominent in patients with high titre inhibitors who needed prolonged treatment or who failed ITI. Longitudinal analysis of 14 patients undergoing ITI revealed that the relative contribution of IgG subclasses was constant for most of the patients analysed. In two patients, the relative contribution of IgG4 increased during ITI. Overall, our findings document the distribution and dynamics of anti-FVIII IgG subclasses during ITI. Future studies will need to address whether monitoring the relative contribution of anti-FVIII subclasses IgG1 and IgG4 may be useful for the identification of patients who are at risk of failing ITI.  相似文献   
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Bladder cancer is the second most common urological cancer in the UK, with over 10 000 cases diagnosed annually. With 80% of urothelial bladder cancers being non‐muscle invasive, it is important to understand the treatments available. This review aims to identify and review the literature regarding bacillus Calmette‐Guerin (BCG) treatment. An integrative‐based review was conducted to generate a broad overview of the existing knowledge for BCG treatment. An open search of online databases was conducted to identify articles published in English from the earliest date available to September 2013, using key terms related to BCG. A significant number of articles were identified. To narrow the results and identify the most relevant articles, the search terms were cross‐referenced. The resulting articles were then reviewed using the critical appraisal skills programme framework. The tools provided by CASP give a systematic, transparent and rigorous approach to the quality assessment of research studies. The research articles were then categorized under the following headings: side effects, including local, systemic and age; quality of life; and attrition. The major conclusion from this literature review is that BCG treatment, when given through an induction and maintenance regime, significantly reduces the risk of progression and recurrence. However, there are potential side effects which the patient and the nurse need to be aware. This review also highlighted that there is a lack of research from the UK and that there is a paucity of research showing why patients withdraw from BCG treatment  相似文献   
95.
An underexposed ethical issue raised by tissue engineering is the use of laboratory animals in tissue engineering research. Even though this research results in suffering and loss of life in animals, tissue engineering also has great potential for the development of alternatives to animal experiments. With the objective of promoting a joint effort of tissue engineers and alternative experts to fully realise this potential, this study provides the first comprehensive overview of the possibilities of using tissue‐engineered constructs as a replacement of laboratory animals. Through searches in two large biomedical databases (PubMed, Embase) and several specialised 3R databases, 244 relevant primary scientific articles, published between 1991 and 2011, were identified. By far most articles reviewed related to the use of tissue‐engineered skin/epidermis for toxicological applications such as testing for skin irritation. This review article demonstrates, however, that the potential for the development of alternatives also extends to other tissues such as other epithelia and the liver, as well as to other fields of application such as drug screening and basic physiology. This review discusses which impediments need to be overcome to maximise the contributions that the field of tissue engineering can make, through the development of alternative methods, to the reduction of the use and suffering of laboratory animals. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Current influenza vaccines elicit primarily antibody-based immunity. They require yearly revaccination and cannot be manufactured until the identification of the circulating viral strain(s). These issues remain to be addressed. Here we report a phase Ib trial of a vaccine candidate (FLU-v) eliciting cellular immunity. Thirty-two males seronegative for the challenge virus by hemagglutination inhibition assay participated in this single-center, randomized, double-blind study. Volunteers received one dose of either the adjuvant alone (placebo, n = 16) or FLU-v (500 μg) and the adjuvant (n = 16), both in saline. Twenty-one days later, FLU-v (n = 15) and placebo (n = 13) volunteers were challenged with influenza virus A/Wisconsin/67/2005 (H3N2) and monitored for 7 days. Safety, tolerability, and cellular responses were assessed pre- and postvaccination. Virus shedding and clinical signs were assessed postchallenge. FLU-v was safe and well tolerated. No difference in the prevaccination FLU-v-specific gamma interferon (IFN-γ) response was seen between groups (average ± the standard error of the mean [SEM] for the placebo and FLU-v, respectively, 1.4-fold ± 0.2-fold and 1.6-fold ± 0.5-fold higher than the negative-control value). Nineteen days postvaccination, the FLU-v group, but not the placebo group, developed FLU-v-specific IFN-γ responses (8.2-fold ± 3.9-fold versus 1.3-fold ± 0.1-fold higher than the negative-control value [average ± SEM] for FLU-v versus the placebo [P = 0.0005]). FLU-v-specific cellular responses also correlated with reductions in both viral titers (P = 0.01) and symptom scores (P = 0.02) postchallenge. Increased cellular immunity specific to FLU-v correlates with reductions in both symptom scores and virus loads. (This study has been registered at ClinicalTrials.gov under registration no. NCT01226758 and at hra.nhs.uk under EudraCT no. 2009-014716-35.)  相似文献   
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