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31.
Applied Microbiology and Biotechnology - Herpes simplex virus type 1 (HSV-1) is responsible of common and widespread viral infections in humans through the world, and of rare, but extremely severe,...  相似文献   
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Apoptosis is a tightly regulated cell suicide program that plays an essential role in the maintenance of tissue homeostasis by eliminating unnecessary or harmful cells. Defects in this native defense mechanism promote malignant transformation and frequently confer chemoresistance to transformed cells. Indeed, the evasion of apoptosis has been recognized as a hallmark of cancer. Given that multiple mechanisms function at many levels to orchestrate the regulation of apoptosis, a multitude of opportunities for apoptotic dysregulation are present within the intricate signaling network of cell. Several of the molecular mechanisms by which cancer cells are protected from apoptosis have been elucidated. These advances have facilitated the development of novel apoptosis-inducing agents that have demonstrated single-agent activity against various types of cancers cells and/or sensitized resistant cancer cells to conventional cytotoxic therapies. Herein, we will highlight several of the central modes of apoptotic dysregulation found in cancer. We will also discuss several therapeutic strategies that aim to reestablish the apoptotic response, and thereby eradicate cancer cells, including those that demonstrate resistance to traditional therapies.  相似文献   
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A novel aerobe thermophilic endospore-forming bacterium designated strain AF/04T was isolated from thermal mud located in Euganean hot springs, Abano Terme, Padova, Italy. Strain AF/04T was Gram-positive, motile, rod-shaped, occurring in pairs, or filamentous. The isolate grew between 55 and 67°C (optimum 65°C) and at pH 6.0–7.5 (optimum pH 7.2). The strain was aerobic and grew on maltose, trehalose, and sodium acetate as sole carbon sources. The G + C content of DNA was 53.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain AF/04T falls within the genus Anoxybacillus. Levels of 16S rRNA gene sequence similarity between strain AF/04T and the type strains of recognized Anoxybacillus species ranged from 95 to 99%. Chemotaxonomic data (major isoprenoid quinone–menaquinone-7; major fatty acid iso-C15:0 and anteiso-C17:0) supported the affiliation of strain AF/04T to the genus Anoxybacillus. Based on phenotypic and chemotaxonomic characteristics, 16S rRNA gene sequence analysis and DNA–DNA hybridization data, it was proposed that strain AF/04T (=DSM 17141T = ATCC BAA 1156T) should be placed in the genus Anoxybacillus as the type strain of a novel species, Anoxybacillus thermarum sp. nov.  相似文献   
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Two thermophilic spore-forming strains, with optimum growth temperature at 70 °C, were isolated from compost of the “Experimental System of Composting” (Teora, Avellino, Italy). A phylogenetic analysis based on 16S rRNA gene sequences showed that these organisms represented a new species of the genus Geobacillus. Based on polyphasic taxonomic data the strains represented a novel species for which the name Geobacillus galactosidasius sp. nov. is proposed. The type strain is CF1BT (= ATCC BAA-1450T = DSM 18751T).  相似文献   
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Background/Aims

Experimental and clinical studies have shown the direct toxic effects of cigarette smoke (CS) on the myocardium, independent of vascular effects. However, the underlying mechanisms are not well known.

Methods

Wistar rats were allocated to control (C) and cigarette smoke (CS) groups. CS rats were exposed to cigarette smoke for 2 months.

Results

After that morphometric, functional and biochemical parameters were measured. The echocardiographic study showed enlargement of the left atria, increase in the left ventricular systolic volume and reduced systolic function. Within the cardiac metabolism, exposure to CS decreased beta hydroxy acyl coenzyme A dehydrogenases and citrate synthases and increased lactate dehydrogenases. Peroxisome proliferator-activated receptor alpha (PPARα) and peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) were expressed similarly in both groups. CS increased serum lipids and myocardial triacylglycerols (TGs). These data suggest that impairment in fatty acid oxidation and the accumulation of cardiac lipids characterize lipotoxicity. CS group exhibited increased oxidative stress and decreased antioxidant defense. Finally, the myocyte cross-sectional area and active Caspase 3 were increased in the CS group.

Conclusion

The cardiac remodeling that was observed in the CS exposure model may be explained by abnormalities in energy metabolism, including lipotoxicity and oxidative stress.  相似文献   
38.
Gastrotrichs are meiobenthic invertebrates of obscure origin and unclear phylogenetic alliances. Uncertainties also plague the intra-group relationship with major contrasts between the evolutionary scenarios inferred from morphology or molecules. In this study we analysed partial sequences of the 18S rDNA gene of 18 taxa (14 new and 4 published) to test morphological estimates of gastrotrich phylogeny and to verify whether controversial interrelationships from previous molecular data are due to poor sampling. Data were analysed using both maximum parsimony and maximum likelihood. MP topology was then forced to reflect published morphological estimates and the most parsimonious solutions from each constraint analysis was statistically compared against the unconstrained solution. MP analysis yielded a single tree with few nodes well supported by bootstrap resampling. These included the monophyly of the Chaetonotidae and the internal relationships of the members of this family, with Aspidiophorus appearing as the most basal member. The monophyly of the Turbanellidae was also well supported with some suggestion that its sister group might be Mesodasys. Lepidodasyidae was found to be an unnatural taxon with Lepidodasys forming a separated clade but unrelated also to the Thaumastodermatidae. With the exception of genera Lepidodasys and Neodasys, the Macrodasyida appeared to be resolved separately from the Chaetonotida, and Dactylopodola was resolved as the most basal macrodasyid. ML analysis yielded a tree not too dissimilar from MP, although Dactylopodola and Xenodasys were resolved as a clade. Statistics indicate that the output from our MP analysis is compatible with the classical view placing representatives of the two orders within two distinct evolutionary lines. Most of the constrained solutions, except the shortest, corroborate the monophyly of the two orders, whereas all five constrained solutions support also the notion that sees Neodasys as an early divergent clade along the Chaetonotida branch. Thus, results are generally compatible with the hypothesised evolutionary scenario based on morphological data, but are in contrast with previous findings from molecules. Future research should consider using the complete SSU rDNA gene sequence in their analysis and additional genes for deeper resolution.  相似文献   
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AimThe aim of the present study is to evaluate and quantify the bias of competing risks in an Italian oncologic cohort comparing results from different statistical analysis methods.BackgroundCompeting risks are very common in randomized clinical trials and observational studies, in particular oncology and radiotherapy ones, and their inappropriate management causes results distortions widely present in clinical scientific articles.Materials and methodsThis is a single-institution phase II trial including 41 patients affected by prostate cancer and undergoing radiotherapy (IMRT-SIB) at the University Hospital of Udine.Different outcomes were considered: late toxicities, relapse, death.Death in the absence of relapse or late toxicity was considered as a competing event.ResultsThe Kaplan Meier method, compared to cumulative incidence function method, overestimated the probability of the event of interest (toxicity and biochemical relapse) and of the competing event (death without toxicity/relapse) by 9.36%. The log-rank test, compared to Gray's test, overestimated the probability of the event of interest by 5.26%.The Hazard Ratio's and cause specific hazard's Cox regression are not directly comparable to subdistribution hazard's Fine and Gray's modified Cox regression; nonetheless, the FG model, the best choice for prognostic studies with competing risks, found significant associations not emerging with Cox regression.ConclusionsThis study confirms that using inappropriate statistical methods produces a 10% overestimation in results, as described in the literature, and highlights the importance of taking into account the competing risks bias.  相似文献   
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