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Willy Verstraete Pieter Van de Caveye Vasileios Diamantis 《Bioresource technology》2009,100(23):5537-5545
Environmental protection and the sustainable management of natural resources stand at the foreground of economic and technological activities worldwide. Current sewage technologies, however, deal with diluted wastes and do not focus on recovery and are therefore not sustainable. Here, the most promising methods available for the recovery of nutrients (nitrogen, phosphorus), organic material and energy from “used waters” are examined both at the decentralised and centralised level. Novel approaches for water processing, not implementing aerobic biological treatment as a core technology, are conceived and critically evaluated regarding efficiency, diffuse emissions and requisite costs. By implementing up-concentration of dilute wastewaters, the concentrated stream becomes suitable for the waste-to-energy strategy. 相似文献
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Vasileios A. Tatsis Ioannis G. Tsoulos Athanassios Stavrakoudis 《International journal of peptide research and therapeutics》2009,15(1):1-9
Humanized CAMPATH-1H antibody has been found to have biological applications through the recognition of the CD52 antigen.
A peptide mimotope of the CD52 antigen with the sequence T1SSPSAD7 has been co-crystallized with the CAMPATH-1H antibody. A plethora of hydrogen bond interactions were found to mediate antigen
recognition. An important feature of peptide’s bound conformation was the type I β-turn found in the S3PSA6 peptide’s fragment. Paradoxically, this fact has been underestimated from other researchers. In order to further investigate
the importance of this structural feature and its significance in antibody/antigen binding we have performed molecular dynamics
simulations in explicit water of the T1SSPSAD7 peptide in both antibody free and bound states. We have found that the turn structure has been perfectly retained in the
bound state but it was eliminated in the free state. This fact implies that the turn structure of the peptide is unstable
in aqueous environment and it is induced upon antibody binding. Analysis of the trajectories revealed also several other important
features of the antibody/antigen binding mode. 相似文献
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Vasileios Diamantis Ioannis Papaspyrou Parasxos Melidis Alexander Aivasidis 《Bioprocess and biosystems engineering》2010,33(2):293-298
Aerated channel reactors with a uniform field of aeration may display flow stratification and short-circuit phenomena in wastewater
treatment systems. In this study, we present data suggesting that flow stratification is closely related to the aeration rate
and the arrangement of aerators. A full-scale oxidation ditch, with a total volume of 6,500 m3 and a membrane-diffused aerated zone of 60 × 7 × 5 m (length–width–depth), was selected for water velocity measurements.
Two profiles of the oxidation ditch were studied in detail: the first one was at the end of the aerated zone and the second
one at the end of the anoxic zone. The results of this work demonstrate that the horizontal water velocity at the end of the
aerated zone displayed significant stratification, with maximum velocity near the water surface (0.5–0.7 m/s) and almost zero
velocity at a depth of 2.5 m. At the end of the anoxic zone, water velocity was uniform and equal to 0.27–0.31 m/s. Increasing
the aeration rate from 1,800 to 4,300 m3/h, almost 90% of the water flow was found to discharge through the upper-half of the channel reactor profile. Different options
to mitigate flow stratification of the oxidation ditch are discussed in this paper. 相似文献
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Krauthammer M Kra P Iossifov I Gomez SM Hripcsak G Hatzivassiloglou V Friedman C Rzhetsky A 《Bioinformatics (Oxford, England)》2002,18(Z1):S249-S257
Knowledge on interactions between molecules in living cells is indispensable for theoretical analysis and practical applications in modern genomics and molecular biology. Building such networks relies on the assumption that the correct molecular interactions are known or can be identified by reading a few research articles. However, this assumption does not necessarily hold, as truth is rather an emerging property based on many potentially conflicting facts. This paper explores the processes of knowledge generation and publishing in the molecular biology literature using modelling and analysis of real molecular interaction data. The data analysed in this article were automatically extracted from 50000 research articles in molecular biology using a computer system called GeneWays containing a natural language processing module. The paper indicates that truthfulness of statements is associated in the minds of scientists with the relative importance (connectedness) of substances under study, revealing a potential selection bias in the reporting of research results. Aiming at understanding the statistical properties of the life cycle of biological facts reported in research articles, we formulate a stochastic model describing generation and propagation of knowledge about molecular interactions through scientific publications. We hope that in the future such a model can be useful for automatically producing consensus views of molecular interaction data. 相似文献
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Landscape and Climatic Variations Shaped Secondary Contacts amid Barn Owls of the Western Palearctic
Tristan Cumer Ana Paula Machado Guillaume Dumont Vasileios Bontzorlos Renato Ceccherelli Motti Charter Klaus Dichmann Nicolaos Kassinis Rui Loureno Francesca Manzia Hans-Dieter Martens Laure Prvost Marko Rakovic Inês Roque Felipe Siverio Alexandre Roulin Jrme Goudet 《Molecular biology and evolution》2022,39(1)
The combined actions of climatic variations and landscape barriers shape the history of natural populations. When organisms follow their shifting niches, obstacles in the landscape can lead to the splitting of populations, on which evolution will then act independently. When two such populations are reunited, secondary contact occurs in a broad range of admixture patterns, from narrow hybrid zones to the complete dissolution of lineages. A previous study suggested that barn owls colonized the Western Palearctic after the last glaciation in a ring-like fashion around the Mediterranean Sea, and conjectured an admixture zone in the Balkans. Here, we take advantage of whole-genome sequences of 94 individuals across the Western Palearctic to reveal the complex history of the species in the region using observational and modeling approaches. Even though our results confirm that two distinct lineages colonized the region, one in Europe and one in the Levant, they suggest that it predates the last glaciation and identify a secondary contact zone between the two in Anatolia. We also show that barn owls recolonized Europe after the glaciation from two distinct glacial refugia: a previously identified western one in Iberia and a new eastern one in Italy. Both glacial lineages now communicate via eastern Europe, in a wide and permeable contact zone. This complex history of populations enlightens the taxonomy of Tyto alba in the region, highlights the key role played by mountain ranges and large water bodies as barriers and illustrates the power of population genomics in uncovering intricate demographic patterns. 相似文献
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Amit Kaura Adam Hartley Vasileios Panoulas Ben Glampson Anoop S. V. Shah Jim Davies Abdulrahim Mulla Kerrie Woods Joe Omigie Anoop D. Shah Mark R. Thursz Paul Elliott Harry Hemmingway Bryan Williams Folkert W. Asselbergs Michael OSullivan Graham M. Lord Adam Trickey Jonathan AC Sterne Dorian O. Haskard Narbeh Melikian Darrel P. Francis Wolfgang Koenig Ajay M. Shah Rajesh Kharbanda Divaka Perera Riyaz S. Patel Keith M. Channon Jamil Mayet Ramzi Khamis 《PLoS medicine》2022,19(2)
BackgroundThere is limited evidence on the use of high-sensitivity C-reactive protein (hsCRP) as a biomarker for selecting patients for advanced cardiovascular (CV) therapies in the modern era. The prognostic value of mildly elevated hsCRP beyond troponin in a large real-world cohort of unselected patients presenting with suspected acute coronary syndrome (ACS) is unknown. We evaluated whether a mildly elevated hsCRP (up to 15 mg/L) was associated with mortality risk, beyond troponin level, in patients with suspected ACS.Methods and findingsWe conducted a retrospective cohort study based on the National Institute for Health Research Health Informatics Collaborative data of 257,948 patients with suspected ACS who had a troponin measured at 5 cardiac centres in the United Kingdom between 2010 and 2017. Patients were divided into 4 hsCRP groups (<2, 2 to 4.9, 5 to 9.9, and 10 to 15 mg/L). The main outcome measure was mortality within 3 years of index presentation. The association between hsCRP levels and all-cause mortality was assessed using multivariable Cox regression analysis adjusted for age, sex, haemoglobin, white cell count (WCC), platelet count, creatinine, and troponin.Following the exclusion criteria, there were 102,337 patients included in the analysis (hsCRP <2 mg/L (n = 38,390), 2 to 4.9 mg/L (n = 27,397), 5 to 9.9 mg/L (n = 26,957), and 10 to 15 mg/L (n = 9,593)). On multivariable Cox regression analysis, there was a positive and graded relationship between hsCRP level and mortality at baseline, which remained at 3 years (hazard ratio (HR) (95% CI) of 1.32 (1.18 to 1.48) for those with hsCRP 2.0 to 4.9 mg/L and 1.40 (1.26 to 1.57) and 2.00 (1.75 to 2.28) for those with hsCRP 5 to 9.9 mg/L and 10 to 15 mg/L, respectively. This relationship was independent of troponin in all suspected ACS patients and was further verified in those who were confirmed to have an ACS diagnosis by clinical coding. The main limitation of our study is that we did not have data on underlying cause of death; however, the exclusion of those with abnormal WCC or hsCRP levels >15 mg/L makes it unlikely that sepsis was a major contributor.ConclusionsThese multicentre, real-world data from a large cohort of patients with suspected ACS suggest that mildly elevated hsCRP (up to 15 mg/L) may be a clinically meaningful prognostic marker beyond troponin and point to its potential utility in selecting patients for novel treatments targeting inflammation.Trial registrationClinicalTrials.gov - Amit Kaura and colleagues investigate whether mildly elevated high sensitivity C-reactive protein is associated with mortality risk in patients with suspected acute coronary syndromes. NCT03507309相似文献
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Zhongxin Ma Ashley A. Holland Ilana Szlamkowicz Vasileios Anagnostopoulos Maria Luiza Caldas Nogueira Jonathan D. Caranto Victor L. Davidson 《The Journal of biological chemistry》2022,298(3)
The hemerythrin-like protein from Mycobacterium kansasii (Mka HLP) is a member of a distinct class of oxo-bridged diiron proteins that are found only in mycobacterial species that cause respiratory disorders in humans. Because it had been shown to exhibit weak catalase activity and a change in absorbance on exposure to nitric oxide (NO), the reactivity of Mka HLP toward NO was examined under a variety of conditions. Under anaerobic conditions, we found that NO was converted to nitrite (NO2−) via an intermediate, which absorbed light at 520 nm. Under aerobic conditions NO was converted to nitrate (NO3−). In each of these two cases, the maximum amount of nitrite or nitrate formed was at best stoichiometric with the concentration of Mka HLP. When incubated with NO and H2O2, we observed NO peroxidase activity yielding nitrite and water as reaction products. Steady-state kinetic analysis of NO consumption during this reaction yielded a Km for NO of 0.44 μM and a kcat/Km of 2.3 × 105 M−1s−1. This high affinity for NO is consistent with a physiological role for Mka HLP in deterring nitrosative stress. This is the first example of a peroxidase that uses an oxo-bridged diiron center and a rare example of a peroxidase utilizing NO as an electron donor and cosubstrate. This activity provides a mechanism by which the infectious Mycobacterium may combat against the cocktail of NO and superoxide (O2•−) generated by macrophages to defend against bacteria, as well as to produce NO2− to adapt to hypoxic conditions. 相似文献
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Effects of Se-depletion on glutathione peroxidase and selenoprotein W gene expression in the colon 总被引:6,自引:0,他引:6
Selenium (Se)-containing proteins have important roles in protecting cells from oxidative damage. This work investigated the effects of Se-depletion on the expression of the genes encoding selenoproteins in colonic mucosa from rats fed diets of different Se content and in human intestinal Caco-2 cells grown in Se-adequate or Se-depleted culture medium. Se-depletion produced statistically significant (P<0.05) falls in glutathione peroxidase (GPX) 1 mRNA (60-83%) and selenoprotein W mRNA (73%) levels, a small but significant fall in GPX4 mRNA (17-25%) but no significant change in GPX2. The data show that SelW expression in the colon is highly sensitive to Se-depletion. 相似文献