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51.
Double muscling is a partially recessive trait present in some beef breeds. It shows a high frequency in some breeds, while in others the frequency is low, and double-muscled individuals are rare. The double muscling is caused by an allelic series of mutations that cause a loss of function of the myostatin gene ( GDF8). We describe here a new mutation in the myostatin gene in Marchigiana breed, a typical beef breed of Central Italy, in which rare double-muscling individuals have been described. A PCR product of the third exon was sequenced in subjects phenotypically showing double muscling, and a G > T transversion was discovered that introduces a premature stop codon. The variant found adds to the large series of mutations present in cattle, and particularly to the only two causative of double muscling in the third exon. A PCR-RFLP test is described for the rapid and effective identification of both heterozygous and homozygous subjects. It was applied to a larger survey carried on the same and also in two other beef breeds, Chianina and Romagnola. Further individuals carrying the new variant were found in Marchigiana, but none in the other breeds. The results may be important for a better comprehension of the role of myostatin in muscular development, for commercial use and for the inference of phylogeny of this gene.  相似文献   
52.
Substituted (E)-3-styryl-4H-chromen-4-ones 1ad, 3-[(1E,3E)-4-phenylbuta-1,3-dienyl]-4H-chromen-4-ones 2ad, (E)-3-styryl-2H-chromenes 3ad and 3-[(1E,3E)-4-phenylbuta-1,3-dienyl]-2H-chromenes 4ad were designed and synthesized to improve the anti-picornavirus activity of previously tested analogues. The new compounds were evaluated in vitro against human rhinovirus (HRV) serotypes 1B and 14 and enterovirus (EV) 71. All the compounds interfered with the replication of picornaviruses, although considerable differences were observed in the sensitivity of viruses to each compound. Generally, both HRVs were more susceptible than EV71 and their sensitivity was dependent upon the linker chain length as well as upon the oxidation state of the heterocyclic ring. (E)-3-Styryl-2H-chromene (3a) emerged as the most effective inhibitor of both HRVs showing IC50 values of 0.20 μM and 1.38 μM towards serotype 1B and 14, respectively. The potent activity was also coupled with low cytotoxicity resulting in high therapeutic indexes (250 and 36, respectively). Mechanism of action studies indicated that 3a, like structurally related compounds, behaves as a capsid binder interfering with the early stages of rhinovirus infection, probably at the adsorption and/or uncoating level.  相似文献   
53.
Calpain-3 is an intracellular cysteine protease, belonging to Calpain superfamily and predominantly expressed in skeletal muscle. In human melanoma cell lines and biopsies, we previously identified two novel splicing variants (hMp78 and hMp84) of Calpain-3 gene (CAPN3), which have a significant lower expression in vertical growth phase melanomas and, even lower, in metastases, compared to benign nevi. In the present study, in order to investigate the pathophysiological role played by the longer Calpain-3 variant, hMp84, in melanoma cells, we over-expressed it in A375 and HT-144 cells. In A375 cells, the enforced expression of hMp84 induces p53 stabilization, and modulates the expression of a few p53- and oxidative stress-related genes. Consistently, hMp84 increases the intracellular production of ROS (Reactive Oxygen Species), which lead to oxidative modification of phospholipids (formation of F2-isoprostanes) and DNA damage. Such events culminate in an adverse cell fate, as indicated by the decrease of cell proliferation and by cell death. To a different extent, either the antioxidant N-acetyl-cysteine or the p53 inhibitor, Pifithrin-α, recover cell viability and decrease ROS formation. Similarly to A375 cells, hMp84 over-expression causes inhibition of cell proliferation, cell death, and increase of both ROS levels and F2-isoprostanes also in HT-144 cells. However, in these cells no p53 accumulation occurs. In both cell lines, no significant change of cell proliferation and cell damage is observed in cells over-expressing the mutant hMp84C42S devoid of its enzymatic activity, suggesting that the catalytic activity of hMp84 is required for its detrimental effects. Since a more aggressive phenotype is expected to benefit from down-regulation of mechanisms impairing cell growth and survival, we envisage that Calpain-3 down-regulation can be regarded as a novel mechanism contributing to melanoma progression.  相似文献   
54.
ObjectiveThe role of complement system in the pathogenesis of systemic sclerosis (SSc) has been debated during the last decade but an evident implication in this disease has never been found. We carried out an explorative study on SSc patients to evaluate the expression of soluble and local C5b-9 complement complex and its relation with a complement regulator, the Membrane Cofactor Protein (MCP, CD46) on skin vascular bed as target distinctive of SSc disease. We also analyzed two polymorphic variants in the complement activation gene cluster involving the MCP region.MethodsC5b-9 plasma levels of SSc patients and healthy subjects were analyzed by ELISA assay. Archival skin biopsies of SSc patients and controls were subjected to immunofluorescence analysis to detect C5b-9 and MCP on vascular endothelial cells. The expression of MCP was validated by immunoblot analysis with specific antibody. Polymorphic variants in the MCP gene promoter were tested by a quantitative PCR technique-based allelic discrimination method.ResultsEven though circulating levels of C5b-9 did not differ between SSc and controls, C5b-9 deposition was detected in skin biopsies of SSc patients but not in healthy subjects. MCP was significantly lower in skin vessels of SSc patients than in healthy controls and was associated with the over-expression of two polymorphic variants in the MCP gene promoter, which has been related to more aggressive phenotypes in other immune-mediated diseases.ConclusionsOur results firsty document the local complement activation with an abnormal expression of MCP in skin vessels of SSc patients, suggesting that a subset of SSc patients might be exposed to more severe organ complications and clinical evolution due to abnormal local complement activation.  相似文献   
55.
BackgroundDespite some preliminary evidence, it is still largely unknown whether osteopathic manipulative treatment improves preterm clinical outcomes.ResultsA total of 695 newborns were randomly assigned to either the study group (n= 352) or the control group (n=343). A statistical significant difference was observed between the two groups for the primary outcome (13.8 and 17.5 days for the study and control group respectively, p<0.001, effect size: 0.31). Multivariate analysis showed a reduction of the length of stay of 3.9 days (95% CI -5.5 to -2.3, p<0.001). Furthermore, there were significant reductions with treatment as compared to usual care in cost (difference between study and control group: 1,586.01€; 95% CI 1,087.18 to 6,277.28; p<0.001) but not in daily weight gain. There were no complications associated to the intervention.ConclusionsOsteopathic treatment reduced significantly the number of days of hospitalization and is cost-effective on a large cohort of preterm infants.  相似文献   
56.

Background

Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of metastatic renal cell carcinoma (mRCC). We aimed to assess the association between the baseline values and treatmentrelated modifications of total serum cholesterol (C), triglycerides (T), body mass index (BMI), fasting blood glucose level (FBG) and blood pressure (BP) levels and the outcome of patients treated with everolimus for mRCC.

Methods

177 patients were included in this retrospective analysis. Time to progression (TTP), clinical benefit (CB) and overall survival (OS) were evaluated.

Results

Basal BMI was significantly higher in patients who experienced a CB (p=0,0145). C,T and C+T raises were significantly associated with baseline BMI (p=0.0412, 0.0283 and 0.0001). Median TTP was significantly longer in patients with T raise compared to patients without T (10 vs 6, p=0.030), C (8 vs 5, p=0.042) and C+T raise (10.9 vs 5.0, p=0.003). At the multivariate analysis, only C+T increase was associated with improved TTP (p=0.005). T raise (21.0 vs 14.0, p=0.002) and C+T increase (21.0 vs 14.0, p=0.006) were correlated with improved OS but were not significant at multivariate analysis.

Conclusion

C+T raise is an early predictor for everolimus efficacy for patients with mRCC.  相似文献   
57.
58.
Polymer‐based nanoparticles (NPs) can be efficiently used for the delivery of bioactive molecules for both in vitro and in vivo applications affording high drug loading and controlled release profiles. Within this framework polylactic‐co‐glycolic acid (PLGA) NPs with a diameter of 290 ± 41 nm have been fabricated and loaded with dexamethasone (DXM) using a patented procedure. The aim of the project was to setup a controlled delivery system to promote the in vitro differentiation of Human Gingival Fibroblasts (HGFs). First the uptake of fluorescent PLGA NPs by HGFs cells was investigated; then experiments were also addressed to analyze the specific cell response to DXM, in order to evaluate its functional efficiency in comparison with its conventional addition to the culture medium. The results showed that cells treated with DXM‐loaded NPs acquired the osteoblast phenotype faster in comparison to those treated with the free drug. The slow and sustained release of DXM from PLGA NPs produced a constant and uniform concentration of drug inside cells with long‐term and enhanced biochemical effects. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1381–1387, 2015  相似文献   
59.
A high-sensitivity assay has been developed for the detection of human topoisomerase I with single molecule resolution. The method uses magnetic sepharose beads to concentrate rolling circle products, produced by the amplification of DNA molecules circularized by topoisomerase I and detectable with a confocal microscope as single and discrete dots, once reacted with fluorescent probes. Each dot, corresponding to a single cleavage–religation event mediated by the enzyme, can be counted due to its high signal/noise ratio, allowing detection of 0.3 pM enzyme and representing a valid method to detect the enzyme activity in highly diluted samples.  相似文献   
60.
Progranulin (PGRN) is a widely expressed multifunctional protein, involved in regulation of cell growth and cell cycle progression with a possible involvement in neurodegeneration. We looked for PGRN regulation in three different human neuroblastoma cell lines, following exposure to two different stimuli commonly associated to neurodegeneration: hypoxia and oxidative stress. For gene and protein expression analysis we carried out a quantitative RT-PCR and western blotting analysis. We show that PGRN is strongly up-regulated by hypoxia, through the mitogen-actived protein kinase (MAPK)/extracellular signal-regulated kinase (MEK) signaling cascade. PGRN is not up-regulated by H(2)O(2)-induced oxidative stress. These results suggest that PGRN in the brain could exert a protective role against hypoxic stress, one of principal risk factors involved in frontotemporal dementia pathogenesis.  相似文献   
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