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1.
Rheumatoid arthritis (RA) is an autoimmune arthritis, for which treatment options remain limited. This study investigated the potential role of adoptive cellular gene therapy as a novel means for treating the RA animal model collagen-induced arthritis (CIA). Adoptive transfer of antigen-specific T-cell hybridomas retrovirally transduced to express IL-4 1 day before booster immunization significantly reduced the number of inflamed joints. Cell transfer after clinical onset of disease had no therapeutic effect. Bioluminescence imaging showed that the hybridomas migrated to the inflamed joints, thus delivering the regulatory protein locally at the site of inflammation. The homing was, at least in part, due to chemotaxis in response to proinflammatory chemokines that are expressed in inflamed joints. There were no significant changes in the cytokine milieu of the draining lymph nodes, nor in the systemic levels of anti-collagen antibodies in treated mice. We conclude that the beneficial clinical effects observed in our model were most likely based on the local action(s) of IL-4 in the inflamed joints and that the local delivery (and effects) of regulatory cytokines, like IL-4, constitutes a novel and effective method of preventing organ-specific autoimmune disease and of minimizing systemic adverse effects.  相似文献   
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Crotoxin, a potent neurotoxin from the South American rattlesnake Crotalus durissus terrificus, is a heterodimeric phospholipase A(2) (EC 3.1.1.4), which blocks the release of acetylcholine from peripheral neurons. We previously have suggested the existence of a 48 kDa crotoxin-binding protein in the presynaptic membranes of the electric organ of Torpedo marmorata. Here, we report the purification and characterization of this protein that we called the crotoxin acceptor protein from Torpedo (CAPT). The membranes of electric organs from Torpedo were solubilized with a detergent (4% (w/v) Triton X-100) and CAPT was isolated by affinity chromatography on a crotoxin column. SDS-PAGE showed that the purified protein was homogeneous and cross-linking studies with radioiodinated crotoxin confirmed that it had retained its toxin-binding properties. The purified CAPT has similar molecular mass as crocalbin, a crotoxin-binding protein isolated from porcine brains, yet anti-crocalbin antiserum failed to recognize CAPT. Surface plasmon resonance biosensor technology was used to measure the specific interaction between crotoxin and solubilized CAPT. Using this method, it was possible to follow CAPT throughout the purification procedure. As well, an apparent dissociation constant (K(d)(app)) of 3.4 nM was calculated for the interaction of pure CAPT and crotoxin from the dissociation rate constant (k(off)=1.2 x 10(-2)s(-1)) and the association rate constant (k(on)=3.5 x 10(6)M(-1)s(-1)).  相似文献   
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IntroductionAimed at preparing the basis for planning evidence-based public health measures for preservation/ improvement of nurses’ work ability (WA), the objective was to assess the relationship between WA and sense of coherence (SOC).MethodsA cross-sectional study was conducted in 2018 among 713 nurses in Croatia. The association between poor WA index (PWAI) and SOC score (SOCS), adjusted for possible confounders, was determined by binary logistic regression analysis.ResultsThe results of univariate logistic regression analysis showed a statistically significant negative association between SOCS and PWAI (OR=0.977, 95% CI 0.968 – 0.986, p<0.001). The results of multivariate logistic analysis showed an even stronger statistically significant negative association between SOCS and PWAI (OR=0.966, 95% CI 0.954 – 0.977, p<0.001) when adjusted for confounders.ConclusionsThe present study suggested SOC as an important health promoting resource of nurses which might offer protection regarding work-related stress. Weak SOC could be an important explanatory factor of poor WA. Accordingly, improving SOC by implementing health promotion measures in nurses’ workplace could be an important way to increase the WA among nurses.  相似文献   
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Animal teeth are a common model in studies on dentin adhesive materials. The aim of this study was to compare microstructural parameters (density and diameter of dentinal tubules (DT), peritubular dentin (PTD) thickness, PTD and intertubular dentin (ITD) surface area) and chemical characteristics of canine, porcine, equine, and human root dentin. The middle layers of dentin were harvested just below a cemento-enamel junction from incisors and investigated by means of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS). SEM evaluation of the specimens revealed, that porcine dentin shared most similarities with human dentin. When comparing the density of DTs, canine dentin was also found to be similar to human dentin. Elemental composition of the root dentin did not differ significantly in porcine, equine and human dentin, but in canine dentin higher magnesium value in PTD compared to ITD was found. It is known that microstructural and chemical characteristics affect the strength of the adhesive bonds created among restorative materials and dentin. According to the results of this study, porcine dentin seems to be the most appropriate model to study dental materials to be used in human restorative dentistry.  相似文献   
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Background

A suitable definition of primary care to capture the variety of prevailing international organisation and service-delivery models is lacking.

Aim

Evaluation of strength of primary care in Europe.

Design and setting

International comparative cross-sectional study performed in 2009–2010, involving 27 EU member states, plus Iceland, Norway, Switzerland, and Turkey.

Method

Outcome measures covered three dimensions of primary care structure: primary care governance, economic conditions of primary care, and primary care workforce development; and four dimensions of primary care service-delivery process: accessibility, comprehensiveness, continuity, and coordination of primary care. The primary care dimensions were operationalised by a total of 77 indicators for which data were collected in 31 countries. Data sources included national and international literature, governmental publications, statistical databases, and experts’ consultations.

Results

Countries with relatively strong primary care are Belgium, Denmark, Estonia, Finland, Lithuania, the Netherlands, Portugal, Slovenia, Spain, and the UK. Countries either have many primary care policies and regulations in place, combined with good financial coverage and resources, and adequate primary care workforce conditions, or have consistently only few of these primary care structures in place. There is no correlation between the access, continuity, coordination, and comprehensiveness of primary care of countries.

Conclusion

Variation is shown in the strength of primary care across Europe, indicating a discrepancy in the responsibility given to primary care in national and international policy initiatives and the needed investments in primary care to solve, for example, future shortages of workforce. Countries are consistent in their primary care focus on all important structure dimensions. Countries need to improve their primary care information infrastructure to facilitate primary care performance management.  相似文献   
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Adjunctive corticosteroid treatment to reduce excessive local inflammatory response in pneumonia is controversial. To study the effects of an early local adjunct dexamethasone treatment on the course of pneumonia and inflammatory/cytokine response, mice were intratracheally inoculated with live Porphyromonas gingivalis and treated with either clindamycin (C), dexamethasone (D), C+D combination, or were not treated (Pg). Six mice from each group were euthanized at 6, 24, 72, and 168 hours after inoculation. Levels of tumor necrosis factor (TNF)-α, soluble TNF-α receptors (sTNFR1 and sTNFR2), interleukin (IL)-1β, and IL-6 in the serum and lung-homogenate supernatant were determined. Lung samples were histopathologically assessed and all findings compared to those found in 24 sham-inoculated mice (phosphate-buffered saline [PBS]). Severe P. gingivalis-induced bronchopneumonia progressed from 24 hours, peaked at 72 hours, and resolved after 168 hours with changes in local and systemic cytokine levels. Clindamycin-treated mice developed only mild bronchopneumonia that resolved fast (72 hours) with an early (6-24 hours) normalization of local and systemic cytokine levels. Similar course of pneumonia and cytokine level changes were observed in mice treated with C+D, but later. Early (6-24 hours) local elevation of sTNFRs was observed in C and C+D groups of mice, whereas nontreated (Pg) mice had increased systemic sTNFRs. Severe bronchopneumonia with delayed resolution was observed in D-group mice, with an early local and systemic decrease in sTNFR1 and persistent elevation of local TNF-α. Clindamycin or a clindamycin-dexamethasone combination treatment significantly improves the course of P. gingivalis-aspiration pneumonia, but more so if clindamycin alone is used. A favorable course of pneumonia seems to be associated with an early elevation of sTNFRs and normalization of TNF-α.  相似文献   
10.
Background: Radical inguinal lymphadenectomy (RIL) for bulky metastatic melanoma and non‐melanoma skin cancers of the inguinal region, while shown to improve morbidity and survival oncologically, can result in substantial morbidity from wound complications. Skin defects cannot be closed primarily and the substantial dead space predisposes to seroma, wound dehiscence and infection. Despite the clear need for reconstructive options, extended series describing reconstruction of large inguinal defects in this setting have not been reported. Methods: A prospectively entered, retrospectively reviewed study of 20 consecutive patients undergoing quadriceps keystone island flaps (QKIF) for the closure of complicated inguinal defects is described. Results: There was 100% flap survival, with no partial or complete flap losses. A reduction in wound breakdown/dehiscence from reported rates was seen, with four patients (20%) having wound breakdown, compared to double that rate in reported series. Other wound complications comprised six patients (30%) with mild wound infections, seven patients (35%) with seromas and two patients (10%) with haematomas. Conclusion: The QKIF is an effective means of reconstructing inguinal defects after RIL, particularly in high‐risk patients, and is technically simpler than other reconstructive techniques advocated for this purpose. Furthermore, the QKIF offers patients with advanced disease (where management is primarily palliative) a potentially improved quality of life with reduced operative morbidity.  相似文献   
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