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71.

Purpose

To assess the clinical efficacy and safety of a treatment based on one cycle versus two cycles of intra-articular injections of plasma rich in growth factors (PRGF-Endoret) on patients with knee osteoarthritis (OA).

Methods

Ninety patients with knee OA were included and evaluated. A total of 48 patients received one cycle (OC group) (3 injections on a weekly basis), while 42 patients received two cycles of PRGF-Endoret (TC group) spaced 6 months between them. Patients were evaluated with LEQUESNE and WOMAC scores before treatment and after 48 weeks. Safety assessment was also performed.

Results

A significant reduction of all assessed outcome measures was shown for both groups at 48 weeks compared with baseline values (P < 0.001). Patients of TCs group showed a significantly higher reduction (P < 0.05) in WOMAC stiffness subscales. Regarding LEQUESNE INDEX, a significantly higher reduction was observed in the TC group in all subscales except in pain score. In the maximum walking distance subscale (MCD), the improvement rate was 31.8% higher for the TCs group compared with the OC group (P < 0.01). In addition, the TC group showed a significant improvement in LEQUESNE activities of daily living (ADV) and global subscales of 14.7 and 11.8% (P < 0.05) higher, respectively, than the OC group.

Conclusions

Treatment with two cycles of PRGF did not show a significantly higher pain reduction compared with one cycle treatment. However, two cycles of PRGF showed a significant improvement in WOMAC stiffness, LEQUESNE MCD, LEQUESNE ADV and LEQUESNE global subscales. Therefore, patients treated with two cycles present an improvement in quality of life.

Level of evidence

II.
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72.
Boccia is a Paralympic sport for athletes with locomotor dysfunction. The aim of this observational methodology study was to describe the design of an ad hoc observation instrument for analyzing individual boccia in the BC3 category (for athletes with severe functional impairment) and to show how it can be used in a practical setting to analyze technical and tactical aspects of the game. The observation instrument was designed based on the internal logic and rules of boccia and was then loaded into the Lince software program to create a simple coding tool. The content of the instrument was validated by a panel of experts with extensive experience in Paralympic boccia. The reliability of the resulting data was confirmed by analysis of interobserver agreement, with high kappa values obtained for all criteria. The practical application of the observation system was demonstrated by performing T-pattern analysis of two sample datasets, which revealed underlying behavioral patterns for isolated throws (synchronic) and successive throws (diachronic).  相似文献   
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Objectives: Was to evaluate the effect of different regional anesthetics (articaine with epinephrine versus prilocaine with felypressin) on stress in the extraction of impacted lower third molars in healthy subjects. Sutdy Desing: A prospective single-blind, split-mouth cross-over randomized study was designed, with a control group. The experimental group consisted of 24 otherwise healthy male volunteers, with two impacted lower third molars which were surgically extracted after inferior alveolar nerve block (regional anesthesia), with a fortnight’s interval: the right using 4% articaine with 1:100.000 epinephrine, and the left 3% prilocaine with 1:1.850.000 felypressin. Patients were randomized for the first surgical procedure. To analyze the variation in four stress markers, homovanillic acid, 3-methoxy-4-hydroxyphenylglycol, prolactin and cortisol, 10-mL blood samples were obtained at t = 0, 5, 60, and 120 minutes. The control group consisted of 12 healthy volunteers, who did not undergo either extractions or anesthetic procedures but from whom blood samples were collected and analyzed in the same way. Results: Plasma cortisol increased in the experimental group (multiple range test, P<0.05), the levels being significantly higher in the group receiving 3% prilocaine with 1:1.850,000 felypressin (signed rank test, p<0.0007). There was a significant reduction in homovanillic acid over time in both groups (multiple range test, P<0.05). No significant differences were observed in homovanillic acid, 3-methoxy-4-hydroxyphenylglycol or prolactin concentrations between the experimental and control groups. Conclusions: The effect of regional anesthesia on stress is lower when 4% articaine with 1:100,000 epinephrine is used in this surgical procedure. Key words:Stress markets, epinephrine versus felypressin.  相似文献   
76.
Estuaries serve as habitats and nurseries for many recreationally and commercially important fishes, often contributing recruits to adult populations that remain in close proximity to estuarine environments. Upper-level predatory fish species are among the most sought after by fisheries; thus, an understanding of the trophic dynamics of the community can assist ecological fisheries management of these highly productive ecosystems. Dietary niche overlap within the predatory fish community of Bulls Bay, a subtropical estuary in South Carolina, was assessed by using stable isotope analyses (δ13C and δ15N) to compare seven elasmobranch species and three teleost species. Cownose Rays Rhinoptera bonasus and Finetooth Sharks Carcharhinus isodon had no isotopic overlap with other species and therefore exhibited unique isotopic niche spaces that were indicative of potential resource partitioning. The teleosts and remaining elasmobranchs had varying degrees of overlap, implying shared resources; a high degree of dietary niche overlap was observed among Spotted Seatrout Cynoscion nebulosus, Sandbar Sharks Carcharhinus plumbeus, and Atlantic Sharpnose Sharks Rhizoprionodon terraenovae. Although most pairs of species showed some isotopic overlap, there were also interspecific differences in niche overlap, signifying that this predatory fish community has a widely varied prey base overall. Bulls Bay is an important nursery habitat with a balanced predator community, as illustrated by a combination of unique dietary niches and varying degrees of dietary niche overlap.

Received August 31, 2015; accepted November 9, 2015  相似文献   

77.
Numerous studies have implicated the pRB family of nuclear proteins in the control of cell cycle progression. Although over-expression experiments have revealed that each of these proteins, pRB, p107, and p130, can induce a G(1) cell cycle arrest, mouse knockouts demonstrated distinct developmental requirements for these proteins, as well as partial functional redundancy between family members. To study the mechanism by which the closely related pRB family proteins contribute to cell cycle progression, we generated 3T3 fibroblasts derived from embryos that lack one or more of these proteins (pRB(-/-), p107(-/-), p130(-/-), pRB(-/-)/p107(-/-), pRB(-/-)/p130(-/-), and p107(-/-)/p130(-/-)). By comparing the growth and cell cycle characteristics of these cells, we have observed clear differences in the manner in which they transit through the G(1) and S phases as well as exit from the cell cycle. Deletion of Rb, or more than one of the family members, results in a shortening of G(1) and a lengthening of S phase, as well as a reduction in growth factor requirements. In addition, the individual cell lines showed differential regulation of a subset of E2F-dependent gene promoters, as well as differences in cell cycle-dependent kinase activity. Taken together, these observations suggest that the closely related pRB family proteins affect cell cycle progression through distinct biochemical mechanisms and that their coordinated action may contribute to their diverse functions in various physiological settings.  相似文献   
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The cells of the intervertebral disc (IVD) have an unusual acidic and hyperosmotic microenvironment. They express acid-sensing ion channels (ASICs), gated by extracellular protons and mechanical forces, as well as neurotrophins and their signalling receptors. In the nervous tissues some neurotrophins regulate the expression of ASICs. The expression of ASIC2 and TrkB in human normal and degenerated IVD was assessed using quantitative-PCR, Western blot, and immunohistochemistry. Moreover, we investigated immunohistochemically the expression of ASIC2 in the IVD of TrkB-deficient mice. ASIC2 and TrkB mRNAs were found in normal human IVD and both increased significantly in degenerated IVD. ASIC2 and TrkB proteins were also found co-localized in a variable percentage of cells, being significantly higher in degenerated IVD than in controls. The murine IVD displayed ASIC2 immunoreactivity which was absent in the IVD of TrkB-deficient mice. Present results demonstrate the occurrence of ASIC2 and TrkB in the human IVD, and the increased expression of both in pathological IVD suggest their involvement in IVD degeneration. These data also suggest that TrkB-ligands might be involved in the regulation of ASIC2 expression, and therefore in mechanisms by which the IVD cells accommodate to low pH and hypertonicity.  相似文献   
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