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111.
Cortis C Tessitore A Lupo C Pesce C Fossile E Figura F Capranica L 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(1):135-142
This study aimed to verify whether basketball players are able to maintain strength (handgrip), jump (countermovement jump [CMJ]), sprint (10 m and 10 m bouncing the ball [10 mBB]), and interlimb coordination (i.e., synchronized hand and foot flexions and extensions at 80, 120, and 180 bpm) performances at the end of their game. Ten young (age 15.7 ± 0.2 years) male basketball players volunteered for this study. During the friendly game, heart rate (HR), rate of perceived exertion (RPE), and rate of muscle pain (RMP) were assessed to evaluate the exercise intensity. Overall, players spent 80% of the time playing at intensities higher than 85% HRmax. Main effects (p < 0.05) for game periods emerged for HR and the number of players involved in a single action, with lower occurrence of maximal efforts and higher involvement of teammates after the first 2 periods. At the end of the game, players reported high (p < 0.05) RPE (15.7 ± 2.4) and RMP (5.2 ± 2.3) values; decreased (p < 0.05) sprint capabilities (10 m: pre = 1.79 ± 0.09 seconds, post = 1.84 ± 0.08 seconds; 10 mBB: pre = 1.81 ± 0.11 seconds, post = 1.96 ± 0.08 seconds); increased (p < 0.05) interlimb coordination at 180 bpm (pre = 33.3 ± 20.2 seconds, post = 43.9 ± 19.8 seconds); and maintained jump (pre = 35.2 ± 5.2 cm, post = 35.7 ± 5.2 cm), handgrip (pre = 437 ± 73 N, post = 427 ± 55 N), and coordinative performances at lower frequencies of executions (80 bpm: pre = 59.7 ± 1.3 seconds, post = 60.0 ± 0.0 seconds; 120 bpm: pre = 54.7 ± 12.3 seconds, post = 57.3 ± 6.7 seconds). These findings indicate that the heavy load of the game exerts beneficial effects on the efficiency of executive and attentive control functions involved in complex motor behaviors. Coaches should structure training sessions that couple intense physical exercises with complex coordination tasks to improve the attentional capabilities of the players. 相似文献
112.
Mese G Sellitto C Li L Wang HZ Valiunas V Richard G Brink PR White TW 《Molecular biology of the cell》2011,22(24):4776-4786
Mutations in the GJB2 gene (Cx26) cause deafness in humans. Most are loss-of-function mutations and cause nonsyndromic deafness. Some mutations produce a gain of function and cause syndromic deafness associated with skin disorders, such as keratitis-ichthyosis-deafness syndrome (KIDS). Cx26-G45E is a lethal mutation linked to KIDS that forms constitutively active connexin hemichannels. The pathomechanism(s) by which mutant Cx26 hemichannels perturb normal epidermal cornification are poorly understood. We created an animal model for KIDS by generating an inducible transgenic mouse expressing Cx26-G45E in keratinocytes. Cx26-G45E mice displayed reduced viability, hyperkeratosis, scaling, skin folds, and hair loss. Histopathology included hyperplasia, acanthosis, papillomatosis, increased cell size, and osteal plugging. These abnormalities correlated with human KIDS pathology and were associated with increased hemichannel currents in transgenic keratinocytes. These results confirm the pathogenic nature of the G45E mutation and provide a new model for studying the role of aberrant connexin hemichannels in epidermal differentiation and inherited connexin disorders. 相似文献
113.
Valverde-Islas LE Arrangoiz E Vega E Robert L Villanueva R Reynoso-Ducoing O Willms K Zepeda-Rodríguez A Fortoul TI Ambrosio JR 《PloS one》2011,6(3):e14754
Background
Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function.Methodology/Principal Findings
Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells.Conclusions/Significance
We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton. 相似文献114.
115.
Esposito G Scuderi C Valenza M Togna GI Latina V De Filippis D Cipriano M Carratù MR Iuvone T Steardo L 《PloS one》2011,6(12):e28668
Peroxisome proliferator-activated receptor-γ (PPARγ) has been reported to be involved in the etiology of pathological features of Alzheimer's disease (AD). Cannabidiol (CBD), a Cannabis derivative devoid of psychomimetic effects, has attracted much attention because of its promising neuroprotective properties in rat AD models, even though the mechanism responsible for such actions remains unknown. This study was aimed at exploring whether CBD effects could be subordinate to its activity at PPARγ, which has been recently indicated as its putative binding site. CBD actions on β-amyloid-induced neurotoxicity in rat AD models, either in presence or absence of PPAR antagonists were investigated. Results showed that the blockade of PPARγ was able to significantly blunt CBD effects on reactive gliosis and subsequently on neuronal damage. Moreover, due to its interaction at PPARγ, CBD was observed to stimulate hippocampal neurogenesis. All these findings report the inescapable role of this receptor in mediating CBD actions, here reported. 相似文献
116.
Zulato E Favaretto F Veronese C Campanaro S Marshall JD Romano S Cabrelle A Collin GB Zavan B Belloni AS Rampazzo E Naggert JK Abatangelo G Sicolo N Maffei P Milan G Vettor R 《PloS one》2011,6(4):e19081
Alström Syndrome (ALMS) is a rare genetic disorder (483 living cases), characterized by many clinical manifestations, including blindness, obesity, type 2 diabetes and cardiomyopathy. ALMS is caused by mutations in the ALMS1 gene, encoding for a large protein with implicated roles in ciliary function, cellular quiescence and intracellular transport. Patients with ALMS have extensive fibrosis in nearly all tissues resulting in a progressive organ failure which is often the ultimate cause of death. To focus on the role of ALMS1 mutations in the generation and maintenance of this pathological fibrosis, we performed gene expression analysis, ultrastructural characterization and functional assays in 4 dermal fibroblast cultures from ALMS patients. Using a genome-wide gene expression analysis we found alterations in genes belonging to specific categories (cell cycle, extracellular matrix (ECM) and fibrosis, cellular architecture/motility and apoptosis). ALMS fibroblasts display cytoskeleton abnormalities and migration impairment, up-regulate the expression and production of collagens and despite the increase in the cell cycle length are more resistant to apoptosis. Therefore ALMS1-deficient fibroblasts showed a constitutively activated myofibroblast phenotype even if they do not derive from a fibrotic lesion. Our results support a genetic basis for the fibrosis observed in ALMS and show that both an excessive ECM production and a failure to eliminate myofibroblasts are key mechanisms. Furthermore, our findings suggest new roles for ALMS1 in both intra- and extra-cellular events which are essential not only for the normal cellular function but also for cell-cell and ECM-cell interactions. 相似文献
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Triolo G Accardo-Palumbo A Dieli F Ciccia F Ferrante A Giardina E Sano CD Licata G 《Arthritis research & therapy》2003,5(5):R262-R268
Beh?et's disease is a multisystem disease in which there is evidence of immunological dysregulation. It has been proposed that gamma/delta T cells are involved in its pathogenesis. The aim of the present study was to assess the capacity of gamma/delta T cells with phenotype Vgamma9/Vdelta2, from a group of Italian patients with Beh?et's disease, to proliferate in the presence of various phosphoantigens and to express tumour necrosis factor (TNF) and IL-12 receptors. Twenty-five patients and 45 healthy individuals were studied. Vgamma9/Vdelta2 T cells were analyzed by fluorescence activated cell sorting, utilizing specific monoclonal antibodies. For the expansion of Vgamma9/Vdelta2 T cells, lymphocytes were cultured in the presence of various phosphoantigens. The expression of TNF receptor II and IL-12 receptor beta1 was evaluated with the simultaneous use of anti-TNF receptor II phycoerythrin-labelled (PE) or anti-IL-12 receptor beta1 PE and anti-Vdelta2 T-cell receptor fluorescein isothiocyanate. There was a certain hierarchy in the response of Vgamma9/Vdelta2 T cells toward the different phosphoantigens, with the highest expansion factor obtained with dimethylallyl pyrophosphate and the lowest with xylose 1P. The expansion factor was fivefold greater in patients with active disease than in those with inactive disease or in control individuals. TNF receptor II and IL-12 receptor beta1 expressions were increased in both patients and control individuals. The proportion of Vgamma9/Vdelta2 T cells bearing these receptors was raised in active disease when Vgamma9/Vdelta2 T cells were cultured in the presence of dimethylallyl pyrophosphate. These results indicate that Vgamma9/Vdelta2 T cell activation is correlated with disease progression and probably involved in the pathogenesis. 相似文献