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排序方式: 共有538条查询结果,搜索用时 15 毫秒
101.
Leonard Schmiester Yannik Schlte Frank T. Bergmann Tacio Camba Erika Dudkin Janine Egert Fabian Frhlich Lara Fuhrmann Adrian L. Hauber Svenja Kemmer Polina Lakrisenko Carolin Loos Simon Merkt Wolfgang Müller Dilan Pathirana Elba Raimúndez Lukas Refisch Marcus Rosenblatt Paul L. Stapor Philipp Stdter Dantong Wang Franz-Georg Wieland Julio R. Banga Jens Timmer Alejandro F. Villaverde Sven Sahle Clemens Kreutz Jan Hasenauer Daniel Weindl 《PLoS computational biology》2021,17(1)
Reproducibility and reusability of the results of data-based modeling studies are essential. Yet, there has been—so far—no broadly supported format for the specification of parameter estimation problems in systems biology. Here, we introduce PEtab, a format which facilitates the specification of parameter estimation problems using Systems Biology Markup Language (SBML) models and a set of tab-separated value files describing the observation model and experimental data as well as parameters to be estimated. We already implemented PEtab support into eight well-established model simulation and parameter estimation toolboxes with hundreds of users in total. We provide a Python library for validation and modification of a PEtab problem and currently 20 example parameter estimation problems based on recent studies. 相似文献
102.
A functional high‐content miRNA screen identifies miR‐30 family to boost recombinant protein production in CHO cells 下载免费PDF全文
Simon Fischer Theresa Buck Andreas Wagner Carolin Ehrhart Julia Giancaterino Samuel Mang Matthias Schad Sven Mathias Armaz Aschrafi René Handrick Kerstin Otte 《Biotechnology journal》2014,9(10):1279-1292
The steady improvement of mammalian cell factories for the production of biopharmaceuticals is a key challenge for the biotechnology community. Recently, small regulatory microRNAs (miRNAs) were identified as novel targets for optimizing Chinese hamster ovary (CHO) production cells as they do not add any translational burden to the cell while being capable of regulating entire physiological pathways. The aim of the present study was to elucidate miRNA function in a recombinant CHO‐SEAP cell line by means of a genome‐wide high‐content miRNA screen. This screen revealed that out of the 1, 139 miRNAs examined, 21% of the miRNAs enhanced cell‐specific SEAP productivity mainly resulting in elevated volumetric yields, while cell proliferation was accelerated by 5% of the miRNAs. Conversely, cell death was diminished by 13% (apoptosis) or 4% (necrosis) of all transfected miRNAs. Besides these large number of identified target miRNAs, the outcome of our studies suggest that the entire miR‐30 family substantially improves bioprocess performance of CHO cells. Stable miR‐30 over expressing cells outperformed parental cells by increasing SEAP productivity or maximum cell density of approximately twofold. Our results highlight the application of miRNAs as powerful tools for CHO cell engineering, identified the miR‐30 family as a critical component of cell proliferation, and support the notion that miRNAs are powerful determinants of cell viability. 相似文献
103.
Lithium Fluoride Based Electron Contacts for High Efficiency n‐Type Crystalline Silicon Solar Cells 下载免费PDF全文
James Bullock Peiting Zheng Quentin Jeangros Mahmut Tosun Mark Hettick Carolin M. Sutter‐Fella Yimao Wan Thomas Allen Di Yan Daniel Macdonald Stefaan De Wolf Aïcha Hessler‐Wyser Andres Cuevas Ali Javey 《Liver Transplantation》2016,6(14)
Low‐resistance contact to lightly doped n‐type crystalline silicon (c‐Si) has long been recognized as technologically challenging due to the pervasive Fermi‐level pinning effect. This has hindered the development of certain devices such as n‐type c‐Si solar cells made with partial rear contacts (PRC) directly to the lowly doped c‐Si wafer. Here, a simple and robust process is demonstrated for achieving mΩ cm2 scale contact resistivities on lightly doped n‐type c‐Si via a lithium fluoride/aluminum contact. The realization of this low‐resistance contact enables the fabrication of a first‐of‐its‐kind high‐efficiency n‐type PRC solar cell. The electron contact of this cell is made to less than 1% of the rear surface area, reducing the impact of contact recombination and optical losses, permitting a power conversion efficiency of greater than 20% in the initial proof‐of‐concept stage. The implementation of the LiFx/Al contact mitigates the need for the costly high‐temperature phosphorus diffusion, typically implemented in such a cell design to nullify the issue of Fermi level pinning at the electron contact. The timing of this demonstration is significant, given the ongoing transition from p‐type to n‐type c‐Si solar cell architectures, together with the increased adoption of advanced PRC device structures within the c‐Si photovoltaic industry. 相似文献
104.
Oxidative damage of albumin in advanced liver disease 总被引:1,自引:0,他引:1
Oettl K Stadlbauer V Petter F Greilberger J Putz-Bankuti C Hallström S Lackner C Stauber RE 《Biochimica et biophysica acta》2008,1782(7-8):469-473
Albumin has a number of biological functions and the serum albumin level is related to prognosis in advanced liver disease. Oxidative stress is believed to play an important role in the pathogenesis of liver failure. The aim of the present study was to characterize oxidative modification of albumin in patients with various degrees of liver failure and to investigate implications for its binding function. Patients with liver cirrhosis (n=10), acute-on-chronic liver failure (n=8) and healthy controls (n=15) were included in the study. Three fractions of albumin were separated by HPLC according to the redox state of cysteine-34 and detected by fluorescence as well as UV absorption. Carbonyl groups were measured as a marker of oxidative modification in plasma proteins and, by western blotting, on albumin. Progressive oxidative modification of albumin was found with increasing severity of liver failure indicated by an increased content of carbonyl groups and oxidation of cysteine-34. Fluorescence properties of albumin were altered by oxidation and, in patients with acute-on-chronic liver failure, by high plasma levels of bilirubin. This alteration of albumin fluorescence by bilirubin provides evidence for a preferred binding of bilirubin to the fully reduced form of albumin. 相似文献
105.
Jason D. Roh Nicholas Houstis Andy Yu Bliss Chang Ashish Yeri Haobo Li Ryan Hobson Carolin Lerchenmüller Ana Vujic Vinita Chaudhari Federico Damilano Colin Platt Daniel Zlotoff Richard T. Lee Ravi Shah Michael Jerosch‐Herold Anthony Rosenzweig 《Aging cell》2020,19(6)
Heart failure with preserved ejection fraction (HFpEF) is the most common type of HF in older adults. Although no pharmacological therapy has yet improved survival in HFpEF, exercise training (ExT) has emerged as the most effective intervention to improving functional outcomes in this age‐related disease. The molecular mechanisms by which ExT induces its beneficial effects in HFpEF, however, remain largely unknown. Given the strong association between aging and HFpEF, we hypothesized that ExT might reverse cardiac aging phenotypes that contribute to HFpEF pathophysiology and additionally provide a platform for novel mechanistic and therapeutic discovery. Here, we show that aged (24–30 months) C57BL/6 male mice recapitulate many of the hallmark features of HFpEF, including preserved left ventricular ejection fraction, subclinical systolic dysfunction, diastolic dysfunction, impaired cardiac reserves, exercise intolerance, and pathologic cardiac hypertrophy. Similar to older humans, ExT in old mice improved exercise capacity, diastolic function, and contractile reserves, while reducing pulmonary congestion. Interestingly, RNAseq of explanted hearts showed that ExT did not significantly modulate biological pathways targeted by conventional HF medications. However, it reversed multiple age‐related pathways, including the global downregulation of cell cycle pathways seen in aged hearts, which was associated with increased capillary density, but no effects on cardiac mass or fibrosis. Taken together, these data demonstrate that the aged C57BL/6 male mouse is a valuable model for studying the role of aging biology in HFpEF pathophysiology, and provide a molecular framework for how ExT potentially reverses cardiac aging phenotypes in HFpEF. 相似文献
106.
Carolin Rapp 《Ethnic and racial studies》2013,36(10):1779-1797
Immigration and the ways in which host societies receive newcomers pose challenges for modern civil societies. This article contributes to the ongoing discussion about how ethnic diversity influences tolerance towards immigrants. Compared to previous studies, we analyse tolerance as a sequential concept in order to uncover the effects of contextual diversity on attitudes towards immigrants and the granting of certain rights to this group. Moreover, we distinguish different shares of ethnic groups based on their ethnic and cultural origins both on the independent and dependent variable. The analysis relies on a subnational survey of sixty municipalities in Switzerland, revealing that only certain ethnic groups are seen as an economic and cultural threat. 相似文献
107.
Guillermo Rodríguez‐Hernández Inés González‐Herrero Carolin Walter Sara González de Tena‐Dávila Salma Parvin Oskar Haas Wilhelm Woessmann Martin Stanulla Martin Schrappe Martin Dugas Yasodha Natkunam Alberto Orfao Verónica Domínguez Belén Pintado Oscar Blanco Diego Alonso‐López Javier De Las Rivas Alberto Martín‐Lorenzo Rafael Jiménez Francisco Javier García Criado María Begoña García Cenador Izidore S Lossos Carolina Vicente‐Dueñas Arndt Borkhardt Julia Hauer Isidro Sánchez‐García 《The EMBO journal》2018,37(14)
108.
Martin Ebinger Sascha Lindenlaub Alexander Kunz Michal Rozanski Carolin Waldschmidt Joachim E. Weber Matthias Wendt Benjamin Winter Philipp A. Kellner Sabina Kaczmarek Matthias Endres Heinrich J. Audebert 《Journal of visualized experiments : JoVE》2013,(81)
In acute ischemic stroke, time from symptom onset to intervention is a decisive prognostic factor. In order to reduce this time, prehospital thrombolysis at the emergency site would be preferable. However, apart from neurological expertise and laboratory investigations a computed tomography (CT) scan is necessary to exclude hemorrhagic stroke prior to thrombolysis. Therefore, a specialized ambulance equipped with a CT scanner and point-of-care laboratory was designed and constructed. Further, a new stroke identifying interview algorithm was developed and implemented in the Berlin emergency medical services. Since February 2011 the identification of suspected stroke in the dispatch center of the Berlin Fire Brigade prompts the deployment of this ambulance, a stroke emergency mobile (STEMO). On arrival, a neurologist, experienced in stroke care and with additional training in emergency medicine, takes a neurological examination. If stroke is suspected a CT scan excludes intracranial hemorrhage. The CT-scans are telemetrically transmitted to the neuroradiologist on-call. If coagulation status of the patient is normal and patient''s medical history reveals no contraindication, prehospital thrombolysis is applied according to current guidelines (intravenous recombinant tissue plasminogen activator, iv rtPA, alteplase, Actilyse).Thereafter patients are transported to the nearest hospital with a certified stroke unit for further treatment and assessment of strokeaetiology. After a pilot-phase, weeks were randomized into blocks either with or without STEMO care. Primary end-point of this study is time from alarm to the initiation of thrombolysis. We hypothesized that alarm-to-treatment time can be reduced by at least 20 min compared to regular care. 相似文献
109.
Background
Two-component signal transduction systems are one means of bacteria to respond to external stimuli. The LiaFSR two-component system of Bacillus subtilis consists of a regular two-component system LiaRS comprising the core Histidine Kinase (HK) LiaS and the Response Regulator (RR) LiaR and additionally the accessory protein LiaF, which acts as a negative regulator of LiaRS-dependent signal transduction. The complete LiaFSR system was shown to respond to various peptide antibiotics interfering with cell wall biosynthesis, including bacitracin.Methodology and Principal Findings
Here we study the response of the LiaFSR system to various concentrations of the peptide antibiotic bacitracin. Using quantitative fluorescence microscopy, we performed a whole population study analyzed on the single cell level. We investigated switching from the non-induced ‘OFF’ state into the bacitracin-induced ‘ON’ state by monitoring gene expression of a fluorescent reporter from the RR-regulated liaI promoter. We found that switching into the ‘ON’ state occurred within less than 20 min in a well-defined switching window, independent of the bacitracin concentration. The switching rate and the basal expression rate decreased at low bacitracin concentrations, establishing clear heterogeneity 60 min after bacitracin induction. Finally, we performed time-lapse microscopy of single cells confirming the quantitative response as obtained in the whole population analysis for high bacitracin concentrations.Conclusion
The LiaFSR system exhibits an immediate, heterogeneous and graded response to the inducer bacitracin in the exponential growth phase. 相似文献110.
Chanjuan Guo Judy Simon Rainer Gasche Pascale Sarah Naumann Carolin Bimüller Rodica Pena Andrea Polle Ingrid Kögel-Knabner Bernd Zeller Heinz Rennenberg Michael Dannenmann 《Plant and Soil》2013,369(1-2):657-668