5 resultados para Joaquim Manuel de Macedo


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ThetimingofNeanderthal disappearanceandtheextent to whichthey overlapped with the earliest incoming anatomically modern humans (AMHs)inEurasia arekey questions inpalaeoanthropology1,2 .Deter- mining the spatiotemporal relationship between the two populations is crucial if we are to understand the processes, timing and reasons leading to the disappearance of Neanderthals and the likelihood of cultural and genetic exchange. Serious technical challenges, however, havehinderedreliable datingof the period,as theradiocarbonmethod reaches its limit at 50,000 years ago3 .Herewe apply improved accel- erator mass spectrometry 14C techniques to construct robust chro- nologies from 40 key Mousterian and Neanderthal archaeological sites, ranging fromRussia toSpain.Bayesianagemodellingwas used togenerate probability distributionfunctions todetermine the latest appearancedate.Weshowthat theMousterianendedby41,030–39,260 calibratedyears BP(at95.4%probability) acrossEurope.Wealsodem- onstrate that succeeding ‘transitional’ archaeological industries, one ofwhich has beenlinked withNeanderthals (Cha ˆtelperronian)4 ,end at a similar time. Our data indicate that the disappearance of Nean- derthals occurred at different times in different regions.Comparing the data with results obtained fromthe earliest datedAMHsites in Europe, associated with the Uluzzian technocomplex5 , allows us to quantify the temporal overlap between the two human groups. The results revealasignificantoverlap of 2,600–5,400years (at 95.4%prob- ability).This hasimportant implications formodels seeking toexplain the cultural, technological and biological elements involved in the replacement of Neanderthals byAMHs.Amosaic of populations in Europe during the Middle to Upper Palaeolithic transition suggests that there was ample time for the transmission of cultural and sym- bolic behaviours, as well as possible genetic exchanges, between the two groups.

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Professor Manuel Salto-Tellez of Queen’s University, Belfast, Northern Ireland is an expert histopathologist and molecular diagnostician. Professor Salto-Tellez is a lead investigator at the Northern Ireland Molecular Pathology Laboratory and also serves as a member of the Editorial Advisory Board for Expert Review of Molecular Diagnostics. In this interview, he proposes directions for the future of molecular pathology and molecular diagnostics, integrating all aspects of pathology toward a common goal.

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OBJECTIVE: Studies indicate an inverse association between ductal adenocarcinoma of the pancreas (PDAC) and nasal allergies. However, controversial findings are reported for the association with asthma. Understanding PDAC risk factors will help us to implement appropriate strategies to prevent, treat and diagnose this cancer. This study assessed and characterised the association between PDAC and asthma and corroborated existing reports regarding the association between allergies and PDAC risk.

DESIGN: Information about asthma and allergies was collated from 1297 PDAC cases and 1024 controls included in the PanGenEU case-control study. Associations between PDAC and atopic diseases were studied using multilevel logistic regression analysis. Meta-analyses of association studies on these diseases and PDAC risk were performed applying random-effects model.

RESULTS: Asthma was associated with lower risk of PDAC (OR 0.64, 95% CI 0.47 to 0.88), particularly long-standing asthma (>=17 years, OR 0.39, 95% CI 0.24 to 0.65). Meta-analysis of 10 case-control studies sustained our results (metaOR 0.73, 95% CI 0.59 to 0.89). Nasal allergies and related symptoms were associated with lower risk of PDAC (OR 0.66, 95% CI 0.52 to 0.83 and OR 0.59, 95% CI 0.46 to 0.77, respectively). These results were supported by a meta-analysis of nasal allergy studies (metaOR 0.6, 95% CI 0.5 to 0.72). Skin allergies were not associated with PDAC risk.

CONCLUSIONS: This study shows a consistent inverse association between PDAC and asthma and nasal allergies, supporting the notion that atopic diseases are associated with reduced cancer risk. These results point to the involvement of immune and/or inflammatory factors that may either foster or restrain pancreas carcinogenesis warranting further research to understand the molecular mechanisms driving this association.