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Functional analysis of human Na^+/K^+-ATPase familial or sporadic hemiplegic migraine mutations expressed in Xenopus oocytes

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World Journal of Biological Chemistry 2014年第2期5卷 240-253页

作者： Susan spiller Thomas Friedrich Institute of Chemistry Technical University of Berlin D-10623 Berlin Germany

AIm: Functional characterization of ATP1A2 mutations that are related to familial or sporadic hemiplegic migraine(FHm2, SHm). mETHODS: cRNA of human Na+/K+-ATPase α2- and β1-subunits were injected in Xenopus laevis oocytes. FHm2 or SHm mutations of residues located in putative α/β interaction sites or in the α2-subunit's C-terminal region were investigated. mutants were analyzed by the twoelectrode voltage-clamp(TEVC) technique on Xenopus oocytes. Stationary K+-induced Na+/K+ pump currents were measured, and the voltage dependence of apparent K+ affinity was investigated. Transient currents were recorded as ouabain-sensitive currents in Na+ buffers to analyze kinetics and voltage-dependent presteady state charge translocations. The expression of constructs was verified by preparation of plasma membrane and total membrane fractions of cRNA-injected oocytes. RESULTS: Compared to the wild-type enzyme, the mutants G900R and E902K showed no significant dif-ferences in the voltage dependence of K+-induced currents, and analysis of the transient currents indicated that the extracellular Na+ affinity was not affected. mutant G855R showed no pump activity detectable by TEVC. Also for L994del and Y1009X, pump currents could not be recorded. Analysis of the plasma and total membrane fractions showed that the expressed proteins were not or only minimally targeted to the plasma membrane. Whereas the mutation K1003E had no impact on K+ interaction, D999H affected the voltage dependence of K+-induced currents. Furthermore, kinetics of the transient currents was altered compared to the wild-type enzyme, and the apparent affinity for extracellular Na+ was reduced. CONCLUSION: The investigated FHm2/SHm mutations influence protein function differently depending on the structural impact of the mutated residue.

关键词： Na+/K+-ATPase Electrophysiology Voltage dependence Familial hemiplegic migraine C-terminus β -subunit

In Situ mineralization of Biomass-Derived Hydrogels Boosts Capacitive Electrochemical Energy Storage in Free-Standing 3D Carbon Aerogels

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Energy & Environmental materials 2024年第2期7卷 359-371页

作者： Anjali Achazhiyath Edathil Babak Rezaei Kristoffer Almdal stephan Sylνest Keller National Centre for Nano Fabrication and Characterization DTU NanolabTechnical University of Denmark2800LyngbyDenmark DTU Chemistry Technical University of Denmark2800LyngbyDenmark

Here,a novel fabrication method for making free-standing 3D hierarchical porous carbon aerogels from molecularly engineered biomass-derived hydrogels is *** situ formed flower-like CaCO_(3)molecularly embedded within the hydrogel network regulated the pore structure during in situ mineralization assisted one-step activation graphitization(imAG),while the intrinsic structural integrity of the carbon aerogels was *** homogenously distributed minerals simultaneously acted as a hard template,activating agent,and graphitization *** decomposition of the homogenously distributed CaCO_(3)during imAG followed by the etching of residual CaO through a mild acid washing endowed a robust carbon aerogel with high porosity and excellent electrochemical *** 0.5 mA cm^(-2),the gravimetric capacitance increased from 0.01 F g^(-1)without mineralization to 322 F g^(-1)with imAG,which exceeds values reported for any other free-standing or powder-based biomass-derived carbon *** outstanding cycling stability of~104%after 1000 cycles in 1 m HClO4 was *** assembled symmetric supercapacitor device delivered a high specific capacitance of 376 F g^(-1)and a high energy density of 26 W h kg^(-1)at a power density of 4000 W kg^(-1),with excellent cycling performance(98.5%retention after 2000 cycles).In combination with the proposed 3D printed mold-assisted solution casting(3DmASC),imAG allows for the generation of free-standing carbon aerogel architectures with arbitrary ***,the novel method introduces flexibility in constructing free-standing carbon aerogels from any ionically cross-linkable biopolymer while maintaining the ability to tailor the design,dimensions,and pore size distribution for specific energy storage applications.

关键词： biomass carbon aerogel sustainable energy materials free-standing supercapacitors

The role of decomposition reactions in assessing first-principles predictions of solid stability

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npj Computational materials 2019年第1期5卷 1120-1128页

作者： Christopher J.Bartel Alan W.Weimer stephan Lany Charles B.musgrave Aaron m.Holder Department of Chemical and Biological Engineering University of ColoradoBoulderCO 80309USA National Renewable Energy Laboratory GoldenCO 80401USA Department of Chemistry University of ColoradoBoulderCO 80309USA

The performance of density functional theory approximations for predicting materials thermodynamics is typically assessed by comparing calculated and experimentally determined enthalpies of formation from elemental phases,ΔH_(f).However,a compound competes thermodynamically with both other compounds and their constituent elemental forms,and thus,the enthalpies of the decomposition reactions to these competing phases,ΔH_(d),determine thermodynamic *** evaluated the phase diagrams for 56,791 compounds to classify decomposition reactions into three types:*** that produce elemental phases,*** that produce compounds,and *** that produce *** analysis shows that the decomposition into elemental forms is rarely the competing reaction that determines compound stability and that approximately two-thirds of decomposition reactions involve no elemental *** experimentally reported formation enthalpies for 1012 solid compounds,we assess the accuracy of the generalized gradient approximation(GGA)(PBE)and meta-GGA(SCAN)density functionals for predicting compound *** 646 decomposition reactions that are not trivially the formation reaction,PBE(mean absolute difference between theory and experiment(mAD)=70 meV/atom)and SCAN(mAD=59 meV/atom)perform similarly,and commonly employed correction schemes using fitted elemental reference energies make only a negligible improvement(~2 meV/atom).Furthermore,for 231 reactions involving only compounds(Type 2),the agreement between SCAN,PBE,and experiment is within~35 meV/atom and is thus comparable to the magnitude of experimental uncertainty.

关键词： stability stability solid

An overview of the latest developments in facial imaging

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Forensic Sciences Research 2019年第1期4卷 10-28页

作者： Carl N.stephan Jodi m.Caple Pierre Guyomarc'h Peter Claes Laboratory for Human Craniofacial and Skeletal Identification(HuCS-ID Lab) School of Biomedical SciencesThe University of QueenslandSt LuciaAustralia Unite mixte de Recherche(UmR)5199 De la Préhistoireàl'Actuel:Culture Environnement et Anthropologie(PACEA)Ministère de la Culture et de la Communication(MCC)Centre National de la Recherche Scientifique(CNRS)Universitéde BordeauxPessacFrance Department of Electrical Engineering Department of Electrical Engineering(ESAT)/Processing of Speech and Images(PSI)KU LeuvenLeuvenBelgium medical Imaging Research Center(mIRC) Universitair ZiekenhuisLeuvenBelgium

Facial imaging is a term used to describe methods that use facial images to assist or facili-tate human identification. This pertains to two craniofacial identification procedures that use skulls and faces—facial approximation and photographic superimposition—as well as face-only methods for age progression/regression, the construction of facial graphics from eye-witness memory (including composites and artistic sketches), facial depiction, face mapping and newly emerging methods of molecular photofitting. Given the breadth of these facial imaging techniques, it is not surprising that a broad array of subject-matter experts partici-pate in and/or contribute to the formulation and implementation of these methods (includ-ing forensic odontologists, forensic artists, police officers, electrical engineers, anatomists, geneticists, medical image specialists, psychologists, computer graphic programmers and software developers). As they are concerned with the physical characteristics of humans, each of these facial imaging areas also falls in the domain of physical anthropology, although not all of them have been traditionally regarded as such. This too offers useful opportunities to adapt established methods in one domain to others more traditionally held to be disciplines within physical anthropology (e.g. facial approximation, craniofacial super-imposition and face photo-comparison). It is important to note that most facial imaging methods are not currently used for identification but serve to assist authorities in narrowing or directing investigations such that other, more potent, methods of identification can be used (e.g. DNA). Few, if any, facial imaging approaches can be considered honed end-stage scientific methods, with major opportunities for physical anthropologists to make meaningful contributions. Some facial imaging methods have considerably stronger scientific underpin-nings than others (e.g. facial approximation versus face mapping), some currently lie ent

关键词： Forensic anthropology craniofacial identification facial approximation photographic superimpos-ition facial depiction age progression facial composites molecular photofitting

Stable isotope analysis of diet confirms niche separation of two sympatric species of Namib Desert lizard

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Integrative Zoology 2016年第1期11卷 60-75页

作者： Ian W.mURRAY Hilary m.LEASE Robyn S.HETEm Duncan mITCHELL Andrea FULLER stephan WOODBORNE Brain Function Research Group School of PhysiologyFaculty of Health SciencesUniversity of the WitwatersrandJohannesburgSouth Africa Biology Department Whitman CollegeWalla WallaWashingtonUSA iThemba Laboratories GautengSouth Africa Stable Isotope Laboratory Mammal Research InstituteDepartment of Zoology and EntomologyUniversity of PretoriaPretoriaSouth Africa

We used stable isotopes of carbon and nitrogen to study the trophic niche of two species of insectivorous lizards,the Husab sand lizard Pedioplanis husabensis and Bradfield’s Namib day gecko living sympatrically in the Namib *** measured theδ13C andδ15N ratios in lizard blood tissues with different turnover times(whole blood,red blood cells and plasma)to investigate lizard diet in different *** also measured theδ13C andδ15N ratios in available arthropod prey and plant tissues on the site,to identify the avenues of nutrient movement between lizards and their *** the use of stable isotope mixing models,we found that the two lizard species relied on a largely non-overlapping but seasonally variable array of arthropods:*** primarily fed on termites,beetles and wasps,while *** fed mainly on ants,wasps and *** originating from C3 plants were proportionally higher for *** than for *** during autumn and late autumn/early winter,although not *** to the few available data estimating the trophic transfer of nutrients in ectotherms in mixed C3 and C4/crassulacean acid metabolism(CAm)plant landscapes,we found that our lizard species primarily acquired nutrients that originated from C4/CAm *** work adds an important dimension to the general lack of studies using stable isotope analyses to estimate lizard niche partitioning and resource use.

关键词： Namib Desert niche partitioning Pedioplanis Rhoptropus stable isotopes

Immunomodulatory nanodiamond aggregate-based platform for the treatment of rheumatoid arthritis

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Regenerative Biomaterials 2019年第3期6卷 163-174页

作者： Amanda Pentecost min Ju Kim Sangmin Jeon Young Ji Ko Ick Chan Kwon Yury Gogotsi Kwangmeyung Kim Kara L.spiller Department of materials Science and Engineering College of EngineeringDrexel UniversityPhiladelphiaPAUSA School of Biomedical Engineering Scienceand Health SystemsDrexel UniversityPhiladelphiaPAUSA KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoulSouth Korea Biomedical Research Institute Center for TheragnosisKorea Institute of Science and TechnologySeoulSouth Korea

We previously demonstrated that octadecylamine-functionalized nanodiamond(ND-ODA)and dexamethasone(Dex)-adsorbed ND-ODA(ND-ODA–Dex)promoted anti-inflammatory and proregenerative behavior in human macrophages in *** this study,we performed a pilot study to investigate if these immunomodulatory effects translate when used as a treatment for rheumatoid arthritis in *** local injection in limbs of mice with collagen type II-induced arthritis,microcomputed tomography showed that mice treated with a low dose of ND-ODA and ND-ODA–Dex did not experience bone loss to the levels observed in non-treated arthritic controls.A low dose of ND-ODA and ND-ODA–Dex also reduced macrophage infiltration and expression of proinflammatory mediators iNOS and tumor necrosis factor-a compared to the arthritic control,while a high dose of ND-ODA increased expression of these ***,these results suggest that ND-ODA may be useful as an inherently immunomodulatory platform,and support the need for an in-depth study,especially with respect to the effects of dose.

关键词： drug delivery nanobiomaterials biomaterial–cell interaction

Rapid chromatographic method to decipher distinct alterations in lipid classes in NAFLD/NASH

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World Journal of Hepatology 2013年第10期5卷 558-567页

作者： stephan Laggai Yvette Simon Theo Ranssweiler Alexandra K Kiemer Sonja m Kessler Department of Pharmacy Pharmaceutical Biology Saarland University

AIm: To establish a simple method to quantify lipid classes in liver diseases and to decipher the lipid profile in p62/ImP2-2/IGF2BP2-2 transgenic ***: Liver-specific overexpression of the insulin-like growth factor 2 mRNA binding protein p62/ImP2-2/IGF2BP2-2 was used as a model for *** was induced by feeding a methioninecholine deficient diet. Steatosis was assessed histologically. For thin layer chromatographic analysis, lipids were extracted from freeze-dried tissues by hexane/2-propanol, dried, redissolved, and chromatographically separated by a two-solvent system. Dilution series of lipid standards were chromatographed, detected, andquantified. The detection was performed by either2',7'-dichlorofluoresceine or a sulfuric acid/ethanol ***: Histological analyses confirmed steatosis and steatohepatitis development. The extraction,chromatographic, and detection method showed high inter-assay reproducibility and allowed quantification of the different lipid classes. The analyses confirmed an increase of triglycerides and phosphatidylethanolamine and a decrease in phosphatidylcholine in the methionine-choline deficient diet. The method was used for the first time to asses the lipid classes induced in the p62-overexpressing mouse model and showed a significant increase in all detected lipid species with a prominent increase of triglycerides by 2-fold. Interestingly, the ratio of phosphatidylcholine to phosphatidylethanolamine was decreased, as previously suggested as a marker in the progression from steatosis to ***: The thin layer chromatography analysis allows a reliable quantification of lipid classes and provides detailed insight into the lipogenic effect of p62.

关键词： Non alcoholic steatohepatitis Non alcoholic fatty liver disease Thin layer chromatography ImP2/IGF2BP2 p62 methionine choline deficient diet Polar lipids neutral lipids Phosphatidylcholine/phosphatidylethanolamine ratio Triglycerides

Stability of Ni/SiO2-ZrO2 catalysts towards steaming and coking in the dry reforming of methane with carbon dioxide

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Frontiers of Chemical Science and Engineering 2016年第2期10卷 281-293页

作者： Bettina Stolze Juliane Titus stephan A. Schunk Andrian milano Ekkehard Schwab Roger Glaser Institute of Chemical Technology Universitat Leipzig Lirmestr. 3 04103 Leipzig Germany hte GmbH Kurpfalzring 104 69123 Heidelberg Germany BASF SE Carl-Bosch-Straβe 38 67056 Ludwigshafen Germany

Ni/SiO2-ZrO2 catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N2 sorption, temperature programmed oxidation, temperature programmed reduc- tion, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 ℃, gas hourly space velocity of 6000 and 1800 h^-1 and atmo- spheric pressure. The SiO2-ZrO2 support as obtained through a simple and efficient sol-gel synthesis is highly porous （ABET = 90 m^·g^-1, dp= 4.4 nm） with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation ofmonoclinic ZrO2, even after steaming at 850 ℃ for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15 h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg· g^-1 carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO2-ZrO2 was shown to provide an optimal balance between activity and coking tendency.

关键词： Ni/SiO2-ZrO2 synthesis gas dry reforming,coking steaming

Zinc deficiency in patients with chronic pancreatitis

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World Journal of Gastroenterology 2019年第5期25卷 600-607页

作者： miroslav Vujasinovic AleksANDra Hedstr?m Patrick maisonneuve Roberto Valente Henrik von Horn J-matthias L?hr stephan L Haas Department for Digestive Diseases Karolinska University Hospital Division of Epidemiology and Biostatistics IEO European Institute of Oncology IRCCS Department for Digestive Diseases Sapienza University of Rome Division of Clinical Chemistry Department of Molecular Medicine and Surgery Karolinska Institutet Karolinska University Hospital Department of Clinical Science Intervention and Technology (CLINTEC)Karolinska Institute

BACKGROUND Zinc is a key element in numerous proteins and plays an important role in essential cell functions such as defense against free radicals and DNA damage repair. Chronic pancreatitis(CP) is a chronic inflammation with progressive fibrosis of pancreas ultimately resulting in pancreatic exocrine insufficiency(PEI),which is associated with malnutrition. Studies analyzing zinc levels in patients with CP are sparse and lead to conflicting *** To investigate serum zinc levels in patients with CP of various *** Between October 2015 and march 2018, patients with a diagnosis of CP were identified and recruited from the Pancreatic Outpatient Clinic at the Karolinska University Hospital in Stockholm, Sweden. Demographic, clinical and laboratory data were analyzed. Etiology of CP was determined according to the mANNHEIm classification system into the following etiological subcategories:alcohol consumption, nicotine consumption, hereditary factors, efferent pancreatic duct factors and immunological factors. Pancreatic exocrine function was defined as normal(fecal elastase 1 > 200 μg/g), mildly reduced(100-200μg/g) and severely reduced(fecal elastase 1 mol/L) was present in 39(26.0%) of patients: 22 females and 17 males. In the group of patients with zinc deficiency, 76.7% of patients had an exocrine pancreatic insufficiency(FE-1 mpared to patients 0.002]. Smoking and number of packyears were additionally associated with low zinc levels. The risk of zinc deficiency in current smokers and smokers with ≥ 20 pack-years was approximately three times higher

关键词： Zinc Pancreas Pancreatic exocrine insufficiency Chronic pancreatitis malnutrition