Relation between fitness tests and match performance in elite Italian soccer referees

This study examined the relation between field-test results and match performance in elite Italian soccer referees. Subjects (n = 22) were all experienced elite-level referees enrolled in the Commissione Arbitri Nazionali (CAN) and thus officiating in the Serie A and B Italian championships. Referees were, on separate occasions, tested for fitness (50-m, 200-m, and 12-minute run tests) and observed a minimum of 1 and a maximum of 3 times (n = 39) during Serie A matches. Match analyses were performed considering 11 match activity categories. Analyses of correlations were performed considering 50-m, 200-m, and 12-minute run test performances as independent variables and total distance, maximal speed distance (runs performed at speeds faster than 24 km.h-1), and high-intensity activity distance (runs performed at speeds faster than 18 km.h-1, high intensity activity [HIA]) as dependent variables. Statistical significance was set at p 相似文献   

Role of the adaptor protein CIKS in the activation of the IKK complex

Nuclear factor kappaB (NF-kappaB) plays a pivotal role in numerous cellular processes, including stress response, inflammation, and protection from apoptosis. Therefore, the activity of NF-kappaB needs to be tightly regulated. We have previously identified a novel gene, named CIKS (connection to IkappaB-kinase and SAPK), able to bind the regulatory sub-unit NEMO/IKKgamma and to activate NF-kappaB. Here, we demonstrate that CIKS forms homo-oligomers, interacts with NEMO/IKKgamma, and is recruited to the IKK-complex upon cell stimulation. In addition, we identified the regions of CIKS responsible for these functions. We found that the ability of CIKS to oligomerize, and to be recruited to the IKK-complex is not sufficient to activate the NF-kappaB. In fact, a deletion mutant of CIKS able to oligomerize, to interact with NEMO/IKKgamma, and to be recruited to the IKK-complex does not activate NF-kappaB, suggesting that CIKS needs a second level of regulation to efficiently activate NF-kappaB.     

Protein phosphorylation in rat liver mitochondria

Summary Incubation of rat liver mitochondria in the presence of either [³²P] Pi or ₃₂ ^y -P] ATP resulted in a phosphorylation of four proteins with Mr 50, 47, 44 and 36 kDa, respectively. The endogenous phosphorylation of these proteins in the presence of [³²P] Pi was markedly influenced by the osmolarity of the incubation medium and differentially affected by various effectors of mitochondrial functions, such as Ca²⁺, oligomycin, FCCP, arsenite and dichloroacetate. In particular, the 36 kDa protein, unlike the other proteins, appears to be phosphorylated also by direct incorporation of [³²P], independently of respiratory chain-linked ATP synthesis. The four proteins, located in the mitoplasts, seem to be phosphorylated by diiferent protein kinases, as suggested by the observation that the endogenous phosphorylation of 36 kDa protein resulted selectively increased by addition of exogenous protein kinases, such as casein kinases S and TS. A tentative identification of these phosphorylatable protein is discussed.     

Predicting the effect of a point mutation on a protein fold: the villin and advillin headpieces and their Pro62Ala mutants

Homology modeling of unknown proteins is based on the assumption that highly similar sequences are likely to share the same fold. However, this does not provide any information on the stability of a given fold, which is ultimately determined by the subtle interplay of enthalpic and entropic contributions. Herein it is shown that ab initio atomistic simulations can be used to predict the effect of point mutations on the stability of a protein fold. The calculations indicate that the fold stabilities of two proteins of similar sequence and identical fold, the villin and advillin C-terminal headpiece fragments, are different and that the same P62A point mutation has a dramatic effect on the fold of villin but a minor one on that of advillin. These predictions were subsequently validated by NMR and CD experiments.     

Homeodomain Interacting Protein Kinase 2: A Target for Alzheimer's Beta Amyloid Leading to Misfolded p53 and Inappropriate Cell Survival

Background

Homeodomain interacting protein kinase 2 (HIPK2) is an evolutionary conserved serine/threonine kinase whose activity is fundamental in maintaining wild-type p53 function, thereby controlling the destiny of cells when exposed to DNA damaging agents. We recently reported an altered conformational state of p53 in tissues from patients with Alzheimer''s Disease (AD) that led to an impaired and dysfunctional response to stressors.

Methodology/Principal Findings

Here we examined the molecular mechanisms underlying the impairment of p53 activity in two cellular models, HEK-293 cells overexpressing the amyloid precursor protein and fibroblasts from AD patients, starting from recent findings showing that p53 conformation may be regulated by HIPK2. We demonstrated that beta-amyloid 1–40 induces HIPK2 degradation and alters HIPK2 binding activity to DNA, in turn regulating the p53 conformational state and vulnerability to a noxious stimulus. Expression of HIPK2 was analysed by western blot experiments, whereas HIPK2 DNA binding was examined by chromatin immunoprecipitation analysis. In particular, we evaluated the recruitment of HIPK2 onto some target promoters, including hypoxia inducible factor-1α and metallothionein 2A.

Conclusions/Significance

These results support the existence of a novel amyloid-based pathogenetic mechanism in AD potentially leading to the survival of injured dysfunctional cells.     

DNA Sequence Determinants Controlling Affinity,Stability and Shape of DNA Complexes Bound by the Nucleoid Protein Fis

The abundant Fis nucleoid protein selectively binds poorly related DNA sequences with high affinities to regulate diverse DNA reactions. Fis binds DNA primarily through DNA backbone contacts and selects target sites by reading conformational properties of DNA sequences, most prominently intrinsic minor groove widths. High-affinity binding requires Fis-stabilized DNA conformational changes that vary depending on DNA sequence. In order to better understand the molecular basis for high affinity site recognition, we analyzed the effects of DNA sequence within and flanking the core Fis binding site on binding affinity and DNA structure. X-ray crystal structures of Fis-DNA complexes containing variable sequences in the noncontacted center of the binding site or variations within the major groove interfaces show that the DNA can adapt to the Fis dimer surface asymmetrically. We show that the presence and position of pyrimidine-purine base steps within the major groove interfaces affect both local DNA bending and minor groove compression to modulate affinities and lifetimes of Fis-DNA complexes. Sequences flanking the core binding site also modulate complex affinities, lifetimes, and the degree of local and global Fis-induced DNA bending. In particular, a G immediately upstream of the 15 bp core sequence inhibits binding and bending, and A-tracts within the flanking base pairs increase both complex lifetimes and global DNA curvatures. Taken together, our observations support a revised DNA motif specifying high-affinity Fis binding and highlight the range of conformations that Fis-bound DNA can adopt. The affinities and DNA conformations of individual Fis-DNA complexes are likely to be tailored to their context-specific biological functions.     

Gene Expression Analysis of PTEN Positive Glioblastoma Stem Cells Identifies DUB3 and Wee1 Modulation in a Cell Differentiation Model

The term astrocytoma defines a quite heterogeneous group of neoplastic diseases that collectively represent the most frequent brain tumors in humans. Among them, glioblastoma multiforme represents the most malignant form and its associated prognosis is one of the poorest among tumors of the central nervous system. It has been demonstrated that a small population of tumor cells, isolated from the brain neoplastic tissue, can reproduce the parental tumor when transplanted in immunodeficient mouse. These tumor initiating cells are supposed to be involved in cancer development and progression and possess stem cell-like features; like their normal counterpart, these cells remain quiescent until they are committed to differentiation. Many studies have shown that the role of the tumor suppressor protein PTEN in cell cycle progression is fundamental for tumor dynamics: in low grade gliomas, PTEN contributes to maintain cells in G1 while the loss of its activity is frequently observed in high grade gliomas. The mechanisms underlying the above described PTEN activity have been studied in many tumors, but those involved in the maintenance of tumor initiating cells quiescence remain to be investigated in more detail. The aim of the present study is to shed light on the role of PTEN pathway on cell cycle regulation in Glioblastoma stem cells, through a cell differentiation model. Our results suggest the existence of a molecular mechanism, that involves DUB3 and WEE1 gene products in the regulation of Cdc25a, as functional effector of the PTEN/Akt pathway.     

Genotypic diversity of oscillatoriacean strains belonging to the genera Geitlerinema and Spirulina determined by 16S rDNA restriction analysis

Genotypic diversity of several cyanobacterial strains mostly isolated from marine or brackish waters, belonging to the genera Geitlerinema and Spirulina, was investigated by amplified 16S ribosomal DNA restriction analysis and compared with morphological features and response to salinity. Cluster analysis was performed on amplified 16S rDNA restriction profiles of these strains along with profiles obtained from sequence data of five Spirulina-like strains, including three representatives of the new genus Halospirulina. Our strains with tightly coiled trichomes from hypersaline waters could be assigned to the Halospirulina genus. Among the uncoiled strains, the two strains of hypersaline origin clustered together and were found to be distant from their counterparts of marine and freshwater habitat. Moreover, another cluster, formed by alkali-tolerant strains with tightly coiled trichomes, was well delineated.