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51.
mtDNA analysis reveals a major late Paleolithic population expansion from southwestern to northeastern Europe. 总被引:24,自引:6,他引:18 下载免费PDF全文
A Torroni H J Bandelt L D'Urbano P Lahermo P Moral D Sellitto C Rengo P Forster M L Savontaus B Bonn-Tamir R Scozzari 《American journal of human genetics》1998,62(5):1137-1152
mtDNA sequence variation was studied in 419 individuals from nine Eurasian populations, by high-resolution RFLP analysis, and it was followed by sequencing of the control region of a subset of these mtDNAs and a detailed survey of previously published data from numerous other European populations. This analysis revealed that a major Paleolithic population expansion from the "Atlantic zone" (southwestern Europe) occurred 10,000-15,000 years ago, after the Last Glacial Maximum. As an mtDNA marker for this expansion we identified haplogroup V, an autochthonous European haplogroup, which most likely originated in the northern Iberian peninsula or southwestern France at about the time of the Younger Dryas. Its sister haplogroup, H, which is distributed throughout the entire range of Caucasoid populations and which originated in the Near East approximately 25,000-30,000 years ago, also took part in this expansion, thus rendering it by far the most frequent (40%-60%) haplogroup in western Europe. Subsequent migrations after the Younger Dryas eventually carried those "Atlantic" mtDNAs into central and northern Europe. This scenario, already implied by archaeological records, is given overwhelming support from both the distribution of the autochthonous European Y chromosome type 15, as detected by the probes 49a/f, and the synthetic maps of nuclear data. 相似文献
52.
The Activity of Differentiation Factors Induces Apoptosis in Polyomavirus Large T-Expressing Myoblasts 总被引:2,自引:0,他引:2 下载免费PDF全文
Gian Maria Fimia Vanesa Gottifredi Barbara Bellei Maria Rosaria Ricciardi Agostino Tafuri Paolo Amati Rossella Maione 《Molecular biology of the cell》1998,9(6):1449-1463
It is commonly accepted that pathways that regulate proliferation/differentiation processes, if altered in their normal interplay, can lead to the induction of programmed cell death. In a previous work we reported that Polyoma virus Large Tumor antigen (PyLT) interferes with in vitro terminal differentiation of skeletal myoblasts by binding and inactivating the retinoblastoma antioncogene product. This inhibition occurs after the activation of some early steps of the myogenic program. In the present work we report that myoblasts expressing wild-type PyLT, when subjected to differentiation stimuli, undergo cell death and that this cell death can be defined as apoptosis. Apoptosis in PyLT-expressing myoblasts starts after growth factors removal, is promoted by cell confluence, and is temporally correlated with the expression of early markers of myogenic differentiation. The block of the initial events of myogenesis by transforming growth factor β or basic fibroblast growth factor prevents PyLT-induced apoptosis, while the acceleration of this process by the overexpression of the muscle-regulatory factor MyoD further increases cell death in this system. MyoD can induce PyLT-expressing myoblasts to accumulate RB, p21, and muscle- specific genes but is unable to induce G00 arrest. Several markers of different phases of the cell cycle, such as cyclin A, cdk-2, and cdc-2, fail to be down-regulated, indicating the occurrence of cell cycle progression. It has been frequently suggested that apoptosis can result from an unbalanced cell cycle progression in the presence of a contrasting signal, such as growth factor deprivation. Our data involve differentiation pathways, as a further contrasting signal, in the generation of this conflict during myoblast cell apoptosis. 相似文献
53.
Lamberto Manzoli Maria Elena Flacco Maria Fiore Carlo La Vecchia Carolina Marzuillo Maria Rosaria Gualano Giorgio Liguori Giancarlo Cicolini Lorenzo Capasso Claudio D'Amario Stefania Boccia Roberta Siliquini Walter Ricciardi Paolo Villari 《PloS one》2015,10(6)
Objective
To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both.Design
Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up.Data Sources
Direct contact and structured questionnaires by phone or via internet.Methods
Adults (30–75 years) were included if they were smokers of ≥1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ≥50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence.Main Outcome Measures
Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily.Data Synthesis
We used linear and logistic regression, with region as cluster unit.Results
Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.35–8.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall).Conclusions
Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so.Registration Number
NCT01785537. 相似文献54.
Giuseppina Mattace Raso Claudio Pirozzi Roberta d'Emmanuele di Villa Bianca Raffaele Simeoli Anna Santoro Adriano Lama Francesca Di Guida Roberto Russo Carmen De Caro Raffaella Sorrentino Antonio Calignano Rosaria Meli 《PloS one》2015,10(5)
Palmitoylethanolamide (PEA), a peroxisome proliferator-activated receptor-α agonist, has been demonstrated to reduce blood pressure and kidney damage secondary to hypertension in spontaneously hypertensive rat (SHR). Currently, no information is available concerning the putative effect of PEA on modulating vascular tone. Here, we investigate the mechanisms underpinning PEA blood pressure lowering effect, exploring the contribution of epoxyeicosatrienoic acids, CYP-dependent arachidonic acid metabolites, as endothelium-derived hyperpolarizing factors (EDHF), and renin angiotensin system (RAS) modulation. To achieve this aim SHR and Wistar-Kyoto rats were treated with PEA (30 mg/kg/day) for five weeks. Functional evaluations on mesenteric bed were performed to analyze EDHF-mediated vasodilation. Moreover, mesenteric bed and carotid were harvested to measure CYP2C23 and CYP2J2, the key isoenzymes in the formation of epoxyeicosatrienoic acids, and the soluble epoxide hydrolase, which is responsible for their degradation in the corresponding diols. Effect of PEA on RAS modulation was investigated by analyzing angiotensin converting enzyme and angiotensin receptor 1 expression. Here, we showed that EDHF-mediated dilation in response to acetylcholine was increased in mesenteric beds of PEA-treated SHR. Western blot analysis revealed that the increase in CYP2C23 and CYP2J2 observed in SHR was significantly attenuated in mesenteric beds of PEA-treated SHR, but unchanged in the carotids. Interestingly, in both vascular tissues, PEA significantly decreased the soluble epoxide hydrolase protein level, accompanied by a reduced serum concentration of its metabolite 14-15 dihydroxyeicosatrienoic acid, implying a reduction in epoxyeicosatrienoic acid hydrolisis. Moreover, PEA treatment down-regulated angiotensin receptor 1 and angiotensin converting enzyme expression, indicating a reduction in angiotensin II-mediated effects. Consistently, a damping of the activation of angiotensin receptor 1 underlying pathways in mesenteric beds was shown in basal conditions in PEA-treated SHR. In conclusion, our data demonstrate the involvement of epoxyeicosatrienoic acids and renin angiotensin system in the blood pressure lowering effect of PEA. 相似文献
55.
56.
Paolo Cossu-Rocca Sandra Orrù Maria Rosaria Muroni Francesca Sanges Giovanni Sotgiu Sara Ena Giovanna Pira Luciano Murgia Alessandra Manca Maria Gabriela Uras Maria Giuseppina Sarobba Silvana Urru Maria Rosaria De Miglio 《PloS one》2015,10(11)
Background
Triple Negative Breast Cancer (TNBC) accounts for 12–24% of all breast carcinomas, and shows worse prognosis compared to other breast cancer subtypes. Molecular studies demonstrated that TNBCs are a heterogeneous group of tumors with different clinical and pathologic features, prognosis, genetic-molecular alterations and treatment responsivity. The PI3K/AKT is a major pathway involved in the regulation of cell survival and proliferation, and is the most frequently altered pathway in breast cancer, apparently with different biologic impact on specific cancer subtypes. The most common genetic abnormality is represented by PIK3CA gene activating mutations, with an overall frequency of 20–40%. The aims of our study were to investigate PIK3CA gene mutations on a large series of TNBC, to perform a wider analysis on genetic alterations involving PI3K/AKT and BRAF/RAS/MAPK pathways and to correlate the results with clinical-pathologic data.Materials and Methods
PIK3CA mutation analysis was performed by using cobas® PIK3CA Mutation Test. EGFR, AKT1, BRAF, and KRAS genes were analyzed by sequencing. Immunohistochemistry was carried out to identify PTEN loss and to investigate for PI3K/AKT pathways components.Results
PIK3CA mutations were detected in 23.7% of TNBC, whereas no mutations were identified in EGFR, AKT1, BRAF, and KRAS genes. Moreover, we observed PTEN loss in 11.3% of tumors. Deregulation of PI3K/AKT pathways was revealed by consistent activation of pAKT and p-p44/42 MAPK in all PIK3CA mutated TNBC.Conclusions
Our data shows that PIK3CA mutations and PI3K/AKT pathway activation are common events in TNBC. A deeper investigation on specific TNBC genomic abnormalities might be helpful in order to select patients who would benefit from current targeted therapy strategies. 相似文献57.
Antonio Bevilacqua Monica Mischitelli Valeria Pietropaolo Emanuela Ciuffreda Milena Sinigaglia Maria Rosaria Corbo 《PloS one》2015,10(10)
Alicyclobacillus acidoterrestris is the main cause of most spoilage problems in fruit juices and acidic products. Since soil borne species often contaminate fruit juices and do not need strict extreme requirements for survival, it is a great concern to investigate whether and how soil species could evolve from their ecological niches in microbial community to new environments as fruit juices. In this study, 23 isolates of thermo-acidophilic, spore-forming bacteria from soil were characterized by cultural and molecular methods. In addition, 2 strains isolated from a spoilage incident in pear juice were typed. Strains phenotyping showed that they could be grouped into 3 different clusters, and some isolates showed identical or quite similar patterns. Analyzing pH and temperature ranges for growth, the majority of strains were able to grow at values described for many species of Alicyclobacillus. Qualitative utilization of lysine, arginine and indole production from tryptophan revealed, for the first time, deamination of lysine and decarboxylation of arginine. Resistance to 5% NaCl as well as the ability to hydrolyze starch and gelatin, nitrate reduction, catalase and oxidase activities confirmed literature evidences. Examining of 16S rRNA, showed that isolates were divided into three blocks represented by effectively soil species and strains that are moving from soil to other possible growing source characterized by parameters that could strongly influence bacterial survival. RAPD PCR technique evidenced a great variability in banding patterns and, although it was not possible to obtain genotypically well-distinguished groups, it was feasible to appreciate genetic similarity between some strains. In conclusion, the investigation of a microbial community entails a combination of metagenomic and classic culture-dependent approaches to expand our knowledge about Alicyclobacillus and to look for new subspecies. 相似文献
58.
Yeasts isolated from olive mill wastewaters from southern Italy: technological characterization and potential use for phenol removal 总被引:1,自引:0,他引:1
Milena Sinigaglia Nilde Di Benedetto Antonio Bevilacqua Maria Rosaria Corbo Angela Capece Patrizia Romano 《Applied microbiology and biotechnology》2010,87(6):2345-2354
Olive mill wastewater (OMW) samples from two traditional varieties (Peranzana and Ogliarola Garganica) of Apulian region (southern
Italy) and produced through continuous and traditional methods were microbiologically and chemically examined; thus, 104 yeasts
were isolated and selected for further analyses. The strains were identified as Candida boidinii, Pichia holstii, Pichia membranifaciens, and Saccharomyces cerevisiae and analyzed to assess their suitability to metabolize phenols. Based on phenol metabolism, 27 strains were selected and
inoculated into OMW aliquots to determine their ability to reduce phenols in vivo; then, five strains (identified with the
codes 682—C. boidinii and 625, 642, 647, and 941—P. holstii) were used as a cocktail in wastewaters for a final validation step. In this last experiment, the effects of the temperature
(10–30°C) and (NH4)2SO4 (0.0–6.0 g l−1) were studied through a central composite design approach, and the results highlighted that the cocktail was able to reduce
phenols by 40% at 10°C with 6.0 g l−1 of (NH4)2SO4 added. 相似文献
59.
De Rossi A Zanchetta M Vitone F Antonelli G Bagnarelli P Buonaguro L Capobianchi MR Clementi M Abbate I Canducci F Monachetti A Riva E Rozera G Scagnolari C Tagliamonte M Re MC;SIVIM 《The new microbiologica》2010,33(4):293-302
Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a good agreement among the laboratories participating in the study. Since test standardization represents a key step for future application in clinical practice, further studies of the patients' samples are in progress to establish the real meaning and utility of the proviral DNA load for clinical management of HIV-1 infected patients. 相似文献
60.
Lucia Peluso Cristiana de Luca Silvia Bozza Antonio Leonardi Gloria Giovannini Alfonso Lavorgna Gaetano De Rosa Massimo Mascolo Loredana Ortega De Luna Maria Rosaria Catania Luigina Romani Fabio Rossano 《BMC microbiology》2010,10(1):1-11