339 research outputs found
The genetic organisation of prokaryotic two-component system signalling pathways
<p>Abstract</p> <p>Background</p> <p>Two-component systems (TCSs) are modular and diverse signalling pathways, involving a stimulus-responsive transfer of phosphoryl groups from transmitter to partner receiver domains. TCS gene and domain organisation are both potentially informative regarding biological function, interaction partnerships and molecular mechanisms. However, there is currently little understanding of the relationships between domain architecture, gene organisation and TCS pathway structure.</p> <p>Results</p> <p>Here we classify the gene and domain organisation of TCS gene loci from 1405 prokaryotic replicons (>40,000 TCS proteins). We find that 200 bp is the most appropriate distance cut-off for defining whether two TCS genes are functionally linked. More than 90% of all TCS gene loci encode just one or two transmitter and/or receiver domains, however numerous other geometries exist, often with large numbers of encoded TCS domains. Such information provides insights into the distribution of TCS domains between genes, and within genes. As expected, the organisation of TCS genes and domains is affected by phylogeny, and plasmid-encoded TCS exhibit differences in organisation from their chromosomally-encoded counterparts.</p> <p>Conclusions</p> <p>We provide here an overview of the genomic and genetic organisation of TCS domains, as a resource for further research. We also propose novel metrics that build upon TCS gene/domain organisation data and allow comparisons between genomic complements of TCSs. In particular, '<it>percentage orphaned TCS genes</it>' (or 'Dissemination') and '<it>percentage of complex loci</it>' (or 'Sophistication') appear to be useful discriminators, and to reflect mechanistic aspects of TCS organisation not captured by existing metrics.</p
Circulating Fatty Acids and Prostate Cancer Risk: Individual Participant Meta-Analysis of Prospective Studies
Background: Individual studies have suggested that some circulating fatty acids are associated with prostate cancer risk, but have not been large enough to provide precise estimates of associations, particularly by stage and grade of disease. Methods: Principal investigators of prospective studies on circulating fatty acids and prostate cancer were invited to collaborate. Investigators provided individual participant data on circulating fatty acids (weight percent) and other characteristics of prostate cancer cases and controls. Prostate cancer risk by study-specific fifths of 14 fatty acids was estimated using multivariable-adjusted conditional logistic regression. All statistical tests were two-sided. Results: Five thousand and ninety-eight case patients and 6649 control patients from seven studies with an average follow-up of 5.1 (SD = 3.3) years were included. Stearic acid (18:0) was inversely associated with total prostate cancer (odds ratio [OR] Q5 vs Q1 = 0.88, 95% confidence interval [CI] = 0.78 to 1.00, P trend = .043). Prostate cancer risk was, respectively, 14% and 16% greater in the highest fifth of eicosapentaenoic acid (20:5n-3) (OR = 1.14, 95% CI = 1.01 to 1.29, P trend = .001) and docosapentaenoic acid (22:5n-3) (OR = 1.16, 95% CI = 1.02 to 1.33, P trend = .003), but in each case there was heterogeneity between studies (P = .022 and P < .001, respectively). There was heterogeneity in the association between docosapentaenoic acid and prostate cancer by grade of disease (P = .006); the association was statistically significant for low-grade disease but not high-grade disease. The remaining 11 fatty acids were not statistically associated with total prostate cancer risk. Conclusion: There was no strong evidence that circulating fatty acids are important predictors of prostate cancer risk. It is not clear whether the modest associations of stearic, eicosapentaenoic, and docosapentaenoic acid are causal
A meta-analysis of individual participant data reveals an association between circulating levels of IGF-I and prostate cancer risk
The role of insulin-like growth factors (IGF) in prostate cancer development is not fully understood. To investigate the association between circulating concentrations of IGFs (IGF-I, IGF-II, IGFBP-1, IGFBP-2, and IGFBP-3) and prostate cancer risk, we pooled individual participant data from 17 prospective and two cross-sectional studies, including up to 10,554 prostate cancer cases and 13,618 control participants. Conditional logistic regression was used to estimate the ORs for prostate cancer based on the study-specific fifth of each analyte. Overall, IGF-I, IGF-II, IGFBP-2, and IGFBP-3 concentrations were positively associated with prostate cancer risk (Ptrend all †0.005), and IGFBP-1 was inversely associated weakly with risk (Ptrend = 0.05). However, heterogeneity between the prospective and cross-sectional studies was evident (Pheterogeneity = 0.03), unless the analyses were restricted to prospective studies (with the exception of IGF-II, Pheterogeneity = 0.02). For prospective studies, the OR for men in the highest versus the lowest fifth of each analyte was 1.29 (95% confidence interval, 1.16-1.43) for IGF-I, 0.81 (0.68-0.96) for IGFBP-1, and 1.25 (1.12-1.40) for IGFBP-3. These associations did not differ significantly by time-to-diagnosis or tumor stage or grade. Aftermutual adjustment for each of the other analytes, only IGF-I remained associated with risk. Our collaborative study represents the largest pooled analysis of the relationship between prostate cancer risk and circulating concentrations of IGF-I, providing strong evidence that IGF-I is highly likely to be involved in prostate cancer development.</p
Towards a muon collider
A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work
Safety, immunogenicity, and reactogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines given as fourth-dose boosters following two doses of ChAdOx1 nCoV-19 or BNT162b2 and a third dose of BNT162b2 (COV-BOOST): a multicentre, blinded, phase 2, randomised trial
Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires
The production of tt⟠, W+bb⟠and W+cc⟠is studied in the forward region of protonâproton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fbâ1 . The W bosons are reconstructed in the decays WââÎœ , where â denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of , and is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 0.02 \mbox{fb}^{-1}. The bosons are reconstructed in the decays , where denotes muon or electron, while the and quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions
Towards a muon collider
A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work
Erratum: Towards a muon collider
The original online version of this article was revised: The additional reference [139] has been added. Tao Hanâs ORICD ID has been incorrectly assigned to Chengcheng Han and Chengcheng Hanâs ORCID ID to Tao Han. Yang Maâs ORCID ID has been incorrectly assigned to Lianliang Ma, and Lianliang Maâs ORCID ID to Yang Ma. The original article has been corrected
Study of the rare B-s(0) and B-0 decays into the pi(+) pi(-) mu(+) mu(-) final state
A search for the rare decays and is performed in a data set corresponding to an integrated luminosity of 3.0 fb collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/ and with muon pairs that do not originate from a resonance are considered. The first observation of the decay and the first evidence of the decay are obtained and the branching fractions are measured to be and , where the third uncertainty is due to the branching fraction of the decay , used as a normalisation.A search for the rare decays Bs0âÏ+ÏâÎŒ+ÎŒâ and B0âÏ+ÏâÎŒ+ÎŒâ is performed in a data set corresponding to an integrated luminosity of 3.0 fbâ1 collected by the LHCb detector in protonâproton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5â1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0âÏ+ÏâÎŒ+ÎŒâ and the first evidence of the decay B0âÏ+ÏâÎŒ+ÎŒâ are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0âÏ+ÏâÎŒ+ÎŒâ)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))Ă10â8 and B(B0âÏ+ÏâÎŒ+ÎŒâ)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))Ă10â8 , where the third uncertainty is due to the branching fraction of the decay B0âJ/Ï(âÎŒ+ÎŒâ)Kâ(892)0(âK+Ïâ) , used as a normalisation.A search for the rare decays Bs0âÏ+ÏâÎŒ+ÎŒâ and B0âÏ+ÏâÎŒ+ÎŒâ is performed in a data set corresponding to an integrated luminosity of 3.0 fbâ1 collected by the LHCb detector in protonâproton collisions at centre-of-mass energies of 7 and 8 TeV . Decay candidates with pion pairs that have invariant mass in the range 0.5â1.3 GeV/c2 and with muon pairs that do not originate from a resonance are considered. The first observation of the decay Bs0âÏ+ÏâÎŒ+ÎŒâ and the first evidence of the decay B0âÏ+ÏâÎŒ+ÎŒâ are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be B(Bs0âÏ+ÏâÎŒ+ÎŒâ)=(8.6±1.5 (stat)±0.7 (syst)±0.7(norm))Ă10â8 and B(B0âÏ+ÏâÎŒ+ÎŒâ)=(2.11±0.51(stat)±0.15(syst)±0.16(norm))Ă10â8 , where the third uncertainty is due to the branching fraction of the decay B0âJ/Ï(âÎŒ+ÎŒâ)Kâ(892)0(âK+Ïâ) , used as a normalisation.A search for the rare decays and is performed in a data set corresponding to an integrated luminosity of 3.0 fb collected by the LHCb detector in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV. Decay candidates with pion pairs that have invariant mass in the range 0.5-1.3 GeV/ and with muon pairs that do not originate from a resonance are considered. The first observation of the decay and the first evidence of the decay are obtained and the branching fractions, restricted to the dipion-mass range considered, are measured to be and , where the third uncertainty is due to the branching fraction of the decay , used as a normalisation
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