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71.
Psoriasis is a chronic and relapsing inflammatory skin disease, clinically characterized by erythematous and scaly plaques. Treatment approach is mainly driven by disease severity, though several factors should be considered in order to identify the optimal therapeutic choice. Mild psoriasis may be treated with a wide array of topical agents including corticosteroids, vitamin D analogs, keratolytics, and calcipotriol/betamethasone propionate compound. Because guidelines may not provide practical indications regarding the therapeutic approach, the use of topical agents in psoriasis is more individually tailored. In order to homogenize the standard of care, at least in a local setting, we collected the real‐life‐based recommendations for the use of topical therapies from an expert panel, the Tuscany Consensus Group on Psoriasis, representing all leading centers for psoriasis established in Tuscany. With this document, this consensus group sought to define principles guiding the selection of therapeutic agents with straightforward recommendations derived from a real‐life setting.  相似文献   
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The antiarrhythmic efficacy of a new class I agent, penticainide, was evaluated by acute oral drug testing and compared in the same patient population with the efficacy of disopyramide, flecainide, mexiletine and propafenone. Twenty-five patients with high-grade chronic ventricular arrhythmias entered the study. During acute oral drug testing, penticainide (7 mg/kg) was effective (more than 90% reduction in ventricular premature complexes and complete abolition of class 4A and 4B arrhythmias) in 17 of 25 subjects (68%). The mean plasma level of the drug at 90 minutes was 4.4 +/- 1.9 micrograms/ml; at the same time increases in the PQ interval (from 168 +/- 27 to 189 +/- 31 ms, p less than 0.0001) and QRS duration (from 89 +/- 14 to 96 +/- 18 ms, p less than 0.001) were observed. The QTc was slightly but not significantly shortened in the overall population; however, in the subgroup with a basally prolonged QTc (n = 8), a significant reduction was observed (from 456 +/- 8 to 440 +/- 18 ms, p less than 0.02). No adverse effects were reported. The antiarrhythmic efficacy of the other drugs tested in the same population was: disopyramide, 12 of 19 (63%); flecainide, 13 of 24 (54%); propafenone, 13 of 24 (54%); and mexiletine, 7 of 20 (35%). Penticainide appears to be a well-tolerated and effective compound of potential value for treatment of ventricular arrhythmias.  相似文献   
74.
During ageing, a progressive loss of skeletal muscle mass and a decrease in muscle strength and endurance take place, in the condition termed sarcopenia. The mechanisms of sarcopenia are complex and still unclear; however, it is known that muscle atrophy is associated with a decline in the number and/or efficiency of satellite cells, the main contributors to muscle regeneration. Physical exercise proved beneficial in sarcopenia; however, knowledge of the effect of adapted physical exercise on the myogenic properties of satellite cells in aged muscles is limited. In this study the amount and activation state of satellite cells as well as their proliferation and differentiation potential were assessed in situ by morphology, morphometry and immunocytochemistry at light and transmission electron microscopy on 28‐month‐old mice submitted to adapted aerobic physical exercise on a treadmill. Sedentary age‐matched mice served as controls, and sedentary adult mice were used as a reference for an unperturbed control at an age when the capability of muscle regeneration is still high. The effect of physical exercise in aged muscles was further analysed by comparing the myogenic potential of satellite cells isolated from old running and old sedentary mice using an in vitro system that allows observation of the differentiation process under controlled experimental conditions. The results of this ex vivo and in vitro study demonstrated that adapted physical exercise increases the number and activation of satellite cells as well as their capability to differentiate into structurally and functionally correct myotubes (even though the age‐related impairment in myotube formation is not fully reversed): this evidence further supports adapted physical exercise as a powerful, non‐pharmacological approach to counteract sarcopenia and the age‐related deterioration of satellite cell capabilities even at very advanced age.  相似文献   
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Chemokine production by human chondrocytes.   总被引:9,自引:0,他引:9  
OBJECTIVE: To evaluate the role of chondrocytes in producing CXC chemokines [interleukin 8 (IL-8), growth related gene product (GRO-alpha)] and CC chemokines [monocyte chemoattractant protein (MCP-1), macrophage inflammatory protein (MIP-1alpha), RANTES] in patients with rheumatoid arthritis (RA) and osteoarthritis (OA) and subjects after traumatic injury (PT). METHODS: Articular cartilage specimens were obtained from 38 patients with OA and 18 with RA undergoing joint replacement surgery. Healthy human cartilage was obtained from femoral condyles removed after trauma in 11 subjects with no history of joint pathology (PT cases). Chondrocytes were isolated from articular cartilage by sequential enzymatic digestion and cultured in vitro. Chemokine production was investigated in unstimulated condition and after 72 h incubation with proinflammatory [IL-1beta, tumor necrosis factor-alpha (TNF-alpha)] and antiinflammatory [transforming growth factor-beta1 (TGF-beta1), IL-10] mediators. Chemokine concentrations in cell supernatants were evaluated by ELISA. RESULTS: Chondrocytes produce all these chemokines to a different extent. IL-1beta was a more potent stimulus than TNF-alpha in inducing production of all chemokines except MCP-1. We found no statistical differences among chondrocytes isolated from OA, RA, and PT for chemokine production in either basal conditions or after cytokine stimulation. IL-1beta induced chemokine production can be modulated by TGF-beta1 in different ways according to the various chemokines, while IL-10 does not affect IL-1beta induced chemokine production. CONCLUSION: Chondrocytes produce IL-8, GRO-alpha, MCP-1, MIP-1alpha, and RANTES. Proinflammatory factors (IL-1beta, TNF-alpha) effectively upregulate chemokine production, but production is scarcely modulated by the antiinflammatory mediators TGF-beta and IL-10. Chondrocyte derived chemokines may play a role in triggering the mechanisms involved in pathogenesis and persistence of joint diseases.  相似文献   
77.
Recently, novel members of the TNF/TNF receptor superfamily, receptor activator of nuclear factor- kappa B ligand (RANKL), its receptor RANK, and the decoy receptor osteoprotegerin (OPG), have been identified as paracrine mediators of both the immune system and bone functions. The balance of RANK/RANK-L and OPG is critical for osteoclastogenesis modulation and physiological bone remodeling. In order to evaluate whether RANKL/OPG balance is modified by ageing, we analyzed, by imunoassay, systemic levels of OPG and sRANKL in healthy elderly subjects (age range from 70 to over 90 years) and in patients affected by two age-related diseases, osteoarthritis (OA) and polymyalgia rheumatica (PMR), characterized by bone metabolism alteration and involvement of the immune system. We demonstrated that (a) plasma concentrations of OPG increased significantly with age; (b) conversely, sRANKL significantly declined in the group of subjects aged between 81 and 90 years, being similar to the young controls in the other age groups; (c) in OA and PMR, circulating OPG did not differ from plasma levels found in age-matched control groups, while sRANKL concentration was significantly increased compared to controls. Hence, in ageing, the sRANKL/OPG system appears to be modified, with prominent changes in circulating OPG levels; in OA and PMR, the sRANKL/OPG balance alteration was shown to be mainly due to the increase of plasma sRANKL concentration.  相似文献   
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79.

Background  

The administration of rituximab (RTX) in vivo results in B-cell depletion, but evidence for multiple mechanisms of action have been reported. Surprisingly, B cell depletion produced a response in patients with polymyositis, which is characterized as a T cell-mediated autoimmune disorder with biopsy findings similar to Miyoshi myopathy (MM). Indeed, in dysferlinopathies, there is evidence of immune system involvement including the presence of muscle inflammation and a down regulation of the complement inhibitory factor, CD55.  相似文献   
80.
The Authors report the results based on 20 years of practice on obstetric psycho-prophylaxis (PPO). Data on presence at course, on frequency, on primipares/pluripares ratio, on labour, on timing and mode of delivery, are assembled. Moreover, neonatal status at birth and at 10th day of life, are investigated. The data obtained were compared with a control group, constituted by women without any treatment before delivery. The acquired experience confirm the utility of PPO in the ordinary clinical practice.  相似文献   
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