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961.
Martin von Bergen Nico Jehmlich Martin Taubert Carsten Vogt Felipe Bastida Florian-Alexander Herbst Frank Schmidt Hans-Hermann Richnow Jana Seifert 《The ISME journal》2013,7(10):1877-1885
The recent development of metaproteomics has enabled the direct identification and quantification of expressed proteins from microbial communities in situ, without the need for microbial enrichment. This became possible by (1) significant increases in quality and quantity of metagenome data and by improvements of (2) accuracy and (3) sensitivity of modern mass spectrometers (MS). The identification of physiologically relevant enzymes can help to understand the role of specific species within a community or an ecological niche. Beside identification, relative and absolute quantitation is also crucial. We will review label-free and label-based methods of quantitation in MS-based proteome analysis and the contribution of quantitative proteome data to microbial ecology. Additionally, approaches of protein-based stable isotope probing (protein-SIP) for deciphering community structures are reviewed. Information on the species-specific metabolic activity can be obtained when substrates or nutrients are labeled with stable isotopes in a protein-SIP approach. The stable isotopes (13C, 15N, 36S) are incorporated into proteins and the rate of incorporation can be used for assessing the metabolic activity of the corresponding species. We will focus on the relevance of the metabolic and phylogenetic information retrieved with protein-SIP studies and for detecting and quantifying the carbon flux within microbial consortia. Furthermore, the combination of protein-SIP with established tools in microbial ecology such as other stable isotope probing techniques are discussed. 相似文献
962.
963.
Jeremy Gross Ian J. Passmore Jade C. S. Chung Olena Rzhepishevska Madeleine Ramstedt Martin Welch 《生物学前沿》2013,8(4):387-394
The opportunistic pathogen Pseudomonas aeruginosa commonly causes chronic and ultimately deadly lung infections in individuals with the genetic disease cystic fibrosis (CF). P. aeruginosa is metabolically diverse; it displays a remarkable ability to adapt to and successfully occupy almost any niche, including the ecologically complex CF lung. These P. aeruginosa lung infections are a fascinating example of microbial evolution within a “natural” ecosystem. Initially, P. aeruginosa shares the lung niche with a plethora of other microorganisms and is vulnerable to antibiotic challenges. Over time, adaptive evolution leads to certain commonly-observed phenotypic changes within the P. aeruginosa population, some of which render it resistant to antibiotics and apparently help it to out-compete the other species that co-habit the airways. Improving genomics techniques continue to elucidate the evolutionary mechanisms of P. aeruginosa within the CF lung and will hopefully identify new vulnerabilities in this robust and versatile pathogen. 相似文献
964.
965.
966.
Gabrielle K. Y. Lee Harry H. X. Wang Kirin Q. L. Liu Yu Cheung Donald E. Morisky Martin C. S. Wong 《PloS one》2013,8(4)
Background and Objectives
Poor adherence to medications is one of the major public health challenges. Only one-third of the population reported successful control of blood pressure, mostly caused by poor drug adherence. However, there are relatively few reports studying the adherence levels and their associated factors among Chinese patients. This study aimed to study the adherence profiles and the factors associated with antihypertensive drug adherence among Chinese patients.Methods
A cross-sectional study was conducted in an outpatient clinic located in the New Territories Region of Hong Kong. Adult patients who were currently taking at least one antihypertensive drug were invited to complete a self-administered questionnaire, consisting of basic socio-demographic profile, self-perceived health status, and self-reported medication adherence. The outcome measure was the Morisky Medication Adherence Scale (MMAS-8). Good adherence was defined as MMAS scores greater than 6 points (out of a total score of 8 points).Results
From 1114 patients, 725 (65.1%) had good adherence to antihypertensive agents. Binary logistic regression analysis was conducted. Younger age, shorter duration of antihypertensive agents used, job status being employed, and poor or very poor self-perceived health status were negatively associated with drug adherence.Conclusion
This study reported a high proportion of poor medication adherence among hypertensive subjects. Patients with factors associated with poor adherence should be more closely monitored to optimize their drug taking behavior. 相似文献967.
968.
Background
Post-copulatory sexual selection has been shown to shape morphology of male gametes. Both directional and stabilizing selection on sperm phenotype have been documented in vertebrates in response to sexual promiscuity.Methodology
Here we investigated the degree of variance in apical hook length and tail length in six taxa of murine rodents.Conclusions
Tail sperm length and apical hook length were positively associated with relative testis mass, our proxy for levels of sperm competition, thus indicating directional post-copulatory selection on sperm phenotypes. Moreover, our study shows that increased levels of sperm competition lead to the reduction of variance in the hook length, indicating stabilizing selection. Hence, the higher risk of sperm competition affects increasing hook length together with decreasing variance in the hook length. Species-specific post-copulatory sexual selection likely optimizes sperm morphology. 相似文献969.
Martin Czerny Ilan Barchichat Katharina Meszaros Gottfried H. Sodeck Alberto Weber David Reineke Lars Englberger Florian Sch?nhoff Alexander Kadner Hansj?rg Jenni Jürg Schmidli Thierry P. Carrel 《PloS one》2013,8(3)
Objective
To evaluate early and mid-term results in patients undergoing proximal thoracic aortic redo surgery.Methods
We analyzed 60 patients (median age 60 years, median logistic EuroSCORE 40) who underwent proximal thoracic aortic redo surgery between January 2005 and April 2012. Outcome and risk factors were analyzed.Results
In hospital mortality was 13%, perioperative neurologic injury was 7%. Fifty percent of patients underwent redo surgery in an urgent or emergency setting. In 65%, partial or total arch replacement with or without conventional or frozen elephant trunk extension was performed. The preoperative logistic EuroSCORE I confirmed to be a reliable predictor of adverse outcome- (ROC 0.786, 95%CI 0.64–0.93) as did the new EuroSCORE II model: ROC 0.882 95%CI 0.78–0.98. Extensive individual logistic EuroSCORE I levels more than 67 showed an OR of 7.01, 95%CI 1.43–34.27. A EuroSCORE II larger than 28 showed an OR of 4.44 (95%CI 1.4–14.06). Multivariate logistic regression analysis identified a critical preoperative state (OR 7.96, 95%CI 1.51–38.79) but not advanced age (OR 2.46, 95%CI 0.48–12.66) as the strongest independent predictor of in-hospital mortality. Median follow-up was 23 months (1–52 months). One year and five year actuarial survival rates were 83% and 69% respectively. Freedom from reoperation during follow-up was 100%.Conclusions
Despite a substantial early attrition rate in patients presenting with a critical preoperative state, proximal thoracic aortic redo surgery provides excellent early and mid-term results. Higher EuroSCORE I and II levels and a critical preoperative state but not advanced age are independent predictors of in-hospital mortality. As a consequence, age alone should no longer be regarded as a contraindication for surgical treatment in this particular group of patients. 相似文献970.
Mihály K. de Bie Maurits S. Buiten André Gaasbeek Mark J. Boogers Cornelis J. Roos Joanne D. Schuijf M. Jacqueline Krol Ton J. Rabelink Jeroen J. Bax Martin J. Schalij J. Wouter Jukema 《PloS one》2013,8(7)