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31.
The spontaneous alcoholic fermentation of grape must is a complex microbiological process involving a large number of various yeast species, to which the flavour of every traditional wine is largely attributed. Whilst Saccharomyces cerevisiae is primarily responsible for the conversion of sugar to alcohol, the activities of various non-Saccharomyces species enhance wine flavour. In this study, indigenous yeast strains belonging to Metschnikowia pulcherrima var. zitsae as well as Saccharomyces cerevisiae were isolated and characterized from Debina must (Zitsa, Epirus, Greece). In addition, these strains were examined for their effect on the outcome of the wine fermentation process when used sequentially as starter cultures. The resulting wine, as analyzed over three consecutive years, was observed to possess a richer, more aromatic bouquet than wine from a commercial starter culture. These results emphasize the potential of employing indigenous yeast strains for the production of traditional wines with improved flavour.  相似文献   
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OBJECTIVE: To compare c-erbB2 (HER-2/Neu) immunohistochemical staining results obtained in 2 pathology departments and evaluate the reproducibility of staining and assessments. STUDY DESIGN: Ninety primary invasive ductal carcinoma cases constituted the material of this study. For concordant assessment, serial sections from the same tissue blocks were prepared in both Turkey and Greece and were sent to each other. Evaluation of c-erbB2 (HER-2/Neu) staining was done independently in 2 departments by experienced pathologists. Stained slides were evaluated semiquantitatively in Turkey and both semiquantitatively and automatically in Greece. RESULTS: There was complete agreement on staining density in 58 (64.4%) cases in both centers. In 15 cases there were major discordances in staining degrees, and in 17 cases there was a major discordance. Hypothetical treatment decisions based on these results showed that 82% of patients would have been handled the same way. CONCLUSION: Comparison of immunostaining patterns performed at 2 centers provided valuable data that may be used in the development of quality assurance policies. The present study showed the usefulness of multicenter comparative studies in initiating the development of guidelines.  相似文献   
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Free radicals are involved in the protective mechanism of preconditioning (PC), whereas antioxidant compounds abolish this benefit. Melatonin is a hormone with antioxidant properties. The aim of our study was to evaluate the effect of melatonin on infarct size in ischemic preconditioning in vivo. We randomly divided 33 male rabbits into four groups and subjected them to 30 min of myocardial ischemia and 3 h of reperfusion with the following prior interventions: (i) no intervention, (ii) iv melatonin at a total dose of 50 mg/kg, (iii) PC with two cycles of 5 min ischemia and 10 min reperfusion, and (iv) combined melatonin and PC. In a second series of experiments, another antioxidant agent N-acetylcysteine (NAC) was used in a control and in a PC group. Myocardial infarct size was determined and blood samples were drawn at different time points for the determination of lipid peroxidation products, total superoxide dismutase (SOD) activity, and (1)H-NMR spectra to evaluate the changes in the metabolic profile. Melatonin showed no effect on myocardial infarct size in the group of sustained ischemia (42.9 +/- 3.6% vs 47.4 +/- 4.9%) and it did not attenuate the reduction of myocardial infarct size in the PC group (13.6 +/- 2.4% vs 14.0 +/- 1.7%). A similar effect was found in NAC-treated groups (44.8 +/- 3.4% vs 14.3 +/- 1.3%). Lipid peroxidation product levels were significantly elevated in the control and PC groups, whereas melatonin decreased them in both groups. The SOD activity was enhanced in the PC group compared to controls; melatonin kept SOD activity unchanged during ischemia/reperfusion and enhanced its activity when it was combined with PC. Melatonin did not change the metabolic profile of the control and PC groups. Melatonin does not prevent the beneficial effect of ischemic PC on infarct size despite its antioxidant properties.  相似文献   
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Local anesthetics inhibit cell proliferation and induce apoptosis in various cell types. Ropivacaine, a unique, novel tertiary amine-type anesthetic, was shown to inhibit the proliferation of several cell types including keratinocytes. We found that Ropivacaine could inhibit the proliferation and induce apoptosis in an immortalized human keratinocyte line,HaCaT, in a dose- and time-dependent manner and with the deprivation of serum. The dose-dependent induction of apoptosis by ropivacaine was demonstrated by DNA fragmentation analysis and the proteolytic cleavage of a caspase-3 substrate—poly (ADP-ribose) polymerase (PARP). In addition, ropivacaine downregulated the expression of clusterin/ apoliporotein J, a protein with anti-apoptotic properties, in a dose-dependent manner, which well correlated with the induction of apoptosis of HaCaT cells. To investigate the role of clusterin/apoliporotein J in ropivacaine-induced apoptosis,HaCaT cells overexpressing clusterin/apoliporotein J were generated and compared to cells expressing the well established anti-apoptotic Bcl-2 protein. Ectopic overexpression of the secreted form of clusterin/apoliporotein J or Bcl-2decreased the sensitivity of HaCaT cells to toxic effects of ropivacaine as demonstrated by DNA fragmentation, the proteolytic cleavage of PARP and by a reduction in procaspase-3 expression. Furthermore, the downregulation of endogenous clusterin/apolipoprotein J levels by ropivacaine suggested that this might be one mechanism by which ropivacaine induced cell death in HaCaT cells. In conclusion, the ability of ropivacaine to induce antiproliferative responses and to suppress the expression of the anti-apoptotic protein clusterin/apolipoprotein J, combined with previously reported anti-inflammatory activity and analgesic property of the drug, suggests that ropivacaine may have potential utility in the local treatment of tumors.  相似文献   
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Mycobacterium avium subsp. paratuberculosis (MAP) can cause a very serious, often-fatal disease, namely paratuberculosis, in several animal species, especially ruminants. Recently, it has also been implicated in the pathogenesis of Infectious Bowel Disease of man. The aim of this study was to develop a molecular method for the routine detection and identification of MAP, from tissue samples of animal origin. The proposed assay would have to combine optimum performance and cost, with high reproducibility. To this goal, three laboratories in Greece and the Czech Republic undertook different parts of a study that involved evaluation of DNA extraction procedures, and PCR assays, for MAP detection. For DNA extraction we used one in-house, and one commercial method, and for the PCR we assessed a number of different assays, starting with the evaluation of primer specificity with an extended GenBank database search. Based on these results, we chose to assess a one-tube nested, 2 two-tube nested, and a single PCR assay, targeted to different genomic regions of the IS900 element. These four methods were applied on positive and negative control samples, consisted of pure bacterial cultures and formalin-fixed paraffin-embedded (FFPE) tissue samples collected from cattle with paratuberculosis and chickens with M. avium subsp. avium infection. Based on the criteria of reliability and cost, the procedure that performed better was the one-tube nested PCR assay combined with the in-house DNA extraction method. The agreement of the results obtained by the three collaborating laboratories indicates the reliability of the proposed assay even under different laboratory conditions.  相似文献   
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Novel purine analogues bearing nitrate esters were designed and synthesized in an effort to develop compounds triggering endogenous cardioprotective mechanisms such as ischemic preconditioning (IPC) or postconditioning (PostC). The majority of the compounds reduced infarct size compared to the control group in anesthetized rabbits, whereas administration of the most active analogue 16 at a dose of 3.8 μmol/kg resulted on a significant reduction of infarct size, compared to PostC group (13.4 ± 1.9% vs 26.4 ± 2.3%). These findings introduce a novel class of promising pharmacological compounds that could be used as mimics or enhancers of PostC.  相似文献   
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Marian Beekman  Hélène Blanché  Markus Perola  Anti Hervonen  Vladyslav Bezrukov  Ewa Sikora  Friederike Flachsbart  Lene Christiansen  Anton J. M. De Craen  Tom B. L. Kirkwood  Irene Maeve Rea  Michel Poulain  Jean‐Marie Robine  Silvana Valensin  Maria Antonietta Stazi  Giuseppe Passarino  Luca Deiana  Efstathios S. Gonos  Lavinia Paternoster  Thorkild I. A. Sørensen  Qihua Tan  Quinta Helmer  Erik B. van den Akker  Joris Deelen  Francesca Martella  Heather J. Cordell  Kristin L. Ayers  James W. Vaupel  Outi Törnwall  Thomas E. Johnson  Stefan Schreiber  Mark Lathrop  Axel Skytthe  Rudi G. J. Westendorp  Kaare Christensen  Jutta Gampe  Almut Nebel  Jeanine J. Houwing‐Duistermaat  Pieternella Eline Slagboom  Claudio Franceschi  the GEHA consortium 《Aging cell》2013,12(2):184-193
Clear evidence exists for heritability of human longevity, and much interest is focused on identifying genes associated with longer lives. To identify such longevity alleles, we performed the largest genome‐wide linkage scan thus far reported. Linkage analyses included 2118 nonagenarian Caucasian sibling pairs that have been enrolled in 15 study centers of 11 European countries as part of the Genetics of Healthy Aging (GEHA) project. In the joint linkage analyses, we observed four regions that show linkage with longevity; chromosome 14q11.2 (LOD = 3.47), chromosome 17q12‐q22 (LOD = 2.95), chromosome 19p13.3‐p13.11 (LOD = 3.76), and chromosome 19q13.11‐q13.32 (LOD = 3.57). To fine map these regions linked to longevity, we performed association analysis using GWAS data in a subgroup of 1228 unrelated nonagenarian and 1907 geographically matched controls. Using a fixed‐effect meta‐analysis approach, rs4420638 at the TOMM40/APOE/APOC1 gene locus showed significant association with longevity (P‐value = 9.6 × 10?8). By combined modeling of linkage and association, we showed that association of longevity with APOEε4 and APOEε2 alleles explain the linkage at 19q13.11‐q13.32 with P‐value = 0.02 and P‐value = 1.0 × 10?5, respectively. In the largest linkage scan thus far performed for human familial longevity, we confirm that the APOE locus is a longevity gene and that additional longevity loci may be identified at 14q11.2, 17q12‐q22, and 19p13.3‐p13.11. As the latter linkage results are not explained by common variants, we suggest that rare variants play an important role in human familial longevity.  相似文献   
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