检索结果-南通市图书馆

Structural analysis of a nanoparticle containing a lipid bilayer used for detergent-free extraction of membrane proteins

在线全文

学校读者我要写书评

暂无评论

Nano Research 2015年第3期8卷 774-789页

作者： Mohammed j.mshad Vinciane Grimard Ilaria Idini Tim j. Knowles Miriam R. Dowle Naomi Schofield Pooj. Sridhart Yupin Lin Rachael Finka Mark Wheatley Owen R. T. Thomas Richard E. Palmerr Michael Overduin Cedric Govaerts j.an-Marie Ruysschaert karen j. edler Tim R. Dafforn School of Biosciences University of Birmingham Edgbaston Birmingham B 15 2TT UK Universite Libre de Bruxelles SFMB - CP206/2 Bd. du Triomphe Acces 2 1050 Bruxelles Belgium Department of Chemistry University of Bath Claverton Down Bath BA2 7AY UK School of Cancer Studies University of Birmingham Edgbaston Birmingham B 15 2 TT UK Nanoscale Physics Research Laboratory and PSIBS School of Physics and Astronomy University of Birmingham Edgbaston Birmingham B 15 2TT UK School of Chemical Engineering University of Birmingham Edgbaston Birmingham B 15 2TT UK

In the past few years there has been a growth in the use of nanoparticles for stabilizing lipid membranes that contain embedded proteins. These bionanoparticles provide a solution to the challenging problem of membrane protein isolation by maintaining a lipid bilayer essential to protein integrity and activity. We have previously described the use of an amphipathic polymer （poly（styrene-co-maleic add）, SMA） to produce discoidal nanoparticles with a lipid bilayer core containing the embedded protein. However the structure of the nanoparticle itself has not yet been determined. This leaves a maj.r gap in understanding how the SMA stabilizes the encapsulated bilayer and how the bilayer relates physically and structurally to an unencapsulated lipid bilayer. In this paper we address this issue by describing the structure of the SMA lipid particle （SMALP） using data from small angle neutron scattering （SANS）, electron microscopy （EM）, attenuated total reflection Fourier transform infrared spectroscopy （ATR-FTIR）, differential scanning calorimetry （DSC） and nuclear magnetic resonance spectroscopy （NMR）. We show that the particle is disc shaped containing a polymer ＂bracelet＂ encircling the lipid bilayer. The structure and orientation of the individual components within the bilayer and polymer are determined showing that styrene moieties within SMA intercalate between the lipid acyl chains. The dimensions of the encapsulated bilayer are also determined and match those measured for a natural membrane. Taken together, the description of the structure of the SMALP forms the foundation for future development and applications of SMALPs in membrane protein production and analysis.

关键词： nanoparticles lipid polymer membrane proteins structure detergent

A novel diagnostic gene region for distinguishing between two pest fruit flies:Bactrocera tryoni(Froggatt)and Bactrocera neohumeralis(Hardy)(Diptera:Tephritidae)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2024年第4期31卷 1285-1295页

作者： Melissa L.Starkie Elizabeth V.Fowler Alexander M.Piper Xiaocheng Zhu Pauline Wyatt David Gopurenko Matt N.Krosch Francesca Strutt karen F.Armstrong Hamish Patrick Mark K.Schutze Mark j.Blacket Department of Agriculture and Fisheries BiosecurityBrisbaneQueenslandAustralia Agriculture Victoria AgriBioBundooraVictoriaAustralia Department of Primary Industries Wagga Wagga Agricultural InstituteWagga WaggaNew South WalesAustralia Forensic Services Group Queensland Police ServiceBrisbaneQueenslandAustralia Department of Pest-management and Conservation Lincoln UniversityLincolnNew Zealand Better Border Biosecurity(B3 B3nz.org.nz)LincolnNew Zealand

Bactrocera tryoni and Bactrocera neohumeralis are morphologically similar sibling pest fruit fly species that possess different biological attributes,geographic distributions,and host *** need to differentiate between the two species is critical for accurate pest status assessment,management,biosecurity,and maintenance of reference *** morphologically similar,adults may be separated based on subtle characters;however,some characters exhibit intraspecific variability,creating overlap between the two ***,there is currently no single molecular marker or rapid diagnostic assay that can reliably distinguish between *** and ***;therefore,ambiguous samples remain *** we report the first molecular marker that can consistently distinguish between *** and *** diagnostic region consists of two adj.cent single nucleotide polymorphisms(SNPs)within the pangolin(pan)gene *** confirmed the genotypes of each species are consistent across their distributional range,then developed a tetra-primer amplification refractory mutation system(ARMS)PCR assay for rapid diagnosis of the *** assay utilizes four primers in multiplex,with two outer universal primers,and two internal primers:one designed to target two adj.cent SNPs(AA)present in *** and the other targeting adj.cent SNPs present in ***(GG).The assay accurately discriminates between the two species,but their SNP genotypes are shared with other nontarget tephritid fruit fly ***,this assay is most suited to adult diagnostics where species confirmation is necessary in determining ambiguous surveillance trap catches;maintaining pure colony lines;and in Sterile Insect Technique management responses.

关键词： ARMS-PCR colony molecular diagnostics pangolin tetra-primer

Are there sex-based disparities in cataract surgery?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International j.urnal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.Lynch Alan G.Palestine Nathan C.Grove karen L.Christopher Richard S.Davidson Michael j.Taravella Naresh Mandava j.nnifer L.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadj.sted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adj.stment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

Surgical or medical treatment of obesity-associated type 2 diabetesan increasing clinical conundrum

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World j.urnal of Diabetes 2024年第10期15卷 2036-2040页

作者： Ryan j.j.lleh karen L j.nes Md Shahidul Islam Lu Cai Michael Horowitz Adelaide Medical School and Centre of Research Excellence in Translating Nutritional Science to Good Health University of Adelaide Endocrine and Metabolic Unit Royal Adelaide HospitalAdelaide 5000South AustraliaAustralia Department of Biochemistry School of Life SciencesUniversity of KwaZulu-NatalDurban 4000KwaZulu-NatalSouth Africa Pediatric Research Institute Departments of PediatricsRadiation OncologyPharmacology and ToxicologyUniversity of LouisvilleWendy Novak Diabetes InstituteNorton Children’s HospitalLouisvilleKY 40202United States

In this editorial,we comment on the article by He et al,specifically in relation to the efficacy of bariatric surgery vs glucagon-like peptide-1 receptor agonist(GLP-1RA)therapy in the management of type 2 diabetes(T2D)associated with *** surgery has now also been shown to be safe and effective in pre-teens and teenagers with obesity and T2D,but information on newer GLP-1RAs in these groups is predictably *** older individuals(age>65 years),both bariatric surgery and GLP-1RA therapy improve cardiovascular ***-tric surgery is not infrequently associated with post-operative postprandial hypoglycemia,which is not the case with GLP-1RAs and,paradoxically,there is evidence that GLP-1RAs may reduce both the frequency and severity of postprandial *** trials of the long-term efficacy of bariatric surgery and GLP-1RAs are indicated.

关键词： Glucagon-like peptide-1 Glucagon-like peptide-1 receptor agonist Obesity Diabetes Weight loss Bariatric surgery Metabolic surgery Hypoglycemia

Optimal transcorneal electrical stimulation parameters for preserving photoreceptors in a mouse model of retinitis pigmentosa

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第11期19卷 2543-2552页

作者： Sam Enayati karen Chang Anton Lennikov Menglu Yang Cherin Lee Aj.y Ashok Farris Elzaridi Christina Yen Kasim Gunes j.a Xie Kin-Sang Cho Tor Paaske Utheim Dong Feng Chen Schepens Eye Research Institute of Massachusetts Eye and Ear Department of OphthalmologyHarvard Medical SchoolBostonMAUSA Institute of clinical medicine Faculty of MedicineUniversity of OsloOsloNorway Department of Medical Biochemistry Oslo University HospitalUniversity of OsloOsloNorway Department of Ophthalmology Drammen HospitalVestre Viken Hospital TrustDrammenNorway Department of Histology and Embryology School of MedicineMarmara UniversityIstanbulTurkiye

Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors,leading to progressive photoreceptor *** research supports the beneficial effect of electrical stimulation on photoreceptor *** study aims to identify the most effective electrical stimulation parameters and functional advantages of transcorneal electrical stimulation(tcES)in mice affected by inherited retinal ***,the study seeked to analyze the electric field that reaches the retina in both eyes in mice and post-mortem *** this study,we recorded waveforms and voltages directed to the retina during transcorneal electrical stimulation in C57BL/6j.mice using an intraocular needle probe with rectangular,sine,and ramp *** investigate the functional effects of electrical stimulation on photoreceptors,we used human retinal explant cultures and rhodopsin knockout(Rho^(-/-))mice,demonstrating progressive photoreceptor degeneration with *** retinal explants isolated from the donors’eyes were then subj.cted to electrical stimulation and cultured for 48 hours to simulate the neurodegenerative environment in *** density was evaluated by rhodopsin *** vivo Rho^(-/-)mice were subj.cted to two 5-day series of daily transcorneal electrical stimulation using rectangular and ramp *** function and visual perception of mice were evaluated by electroretinography and optomotor response(OMR),*** was used to assess the morphological and biochemical changes of the photoreceptor and bipolar cells in mouse *** recordings indicated effective delivery of rectangular,sine,and ramp waveforms to the retina by transcorneal electrical stimulation,of which the ramp waveform required the lowest *** of the total conductive resistance of the post-mortem human compared to the mouse eyes indicated higher cornea-to-retina resistance in human *** tem

关键词： bipolar cells electrical stimulation neuroprotection photoreceptor degeneration retina retinal explants retinitis pigmentosa transcorneal electrical stimulation waveform

Role of complex organic arsenicals in food in aggregate exposure to arsenic

在线全文

学校读者我要写书评

暂无评论

j.urnal of Environmental Sciences 2016年第11期28卷 86-96页

作者： David j.Thomas karen Bradham Pharmacokinetics Branch Integrated Systems Toxicology Division National Health and Environmental Effects Research Laboratory Offilce of Research and Development U.S. Environmental Protection Agency Research Triangle Parle NC 27709 USA Public Health Chemistry Branch Exposure Methods and Measurements Division National Exposure Research Laboratory Offilce of Researchand Development U.S. Environmental Protection Agency Research Triangle Park NC 27709 USA

For much of the world＇s population, food is the maj.r source of exposure to *** to this non-essential metalloid at relatively low levels may be linked to a wide range of adverse health effects. Thus, evaluating foods as sources of exposure to arsenic is important in assessing risk and developing strategies that protect public health. Although most emphasis has been placed on inorganic arsenic as human carcinogen and toxicant, an array of arsenic-containing species are found in plants and animals used as foods. Here,we 2evaluate the contribution of complex organic arsenicals（arsenosugars, arsenolipids,and trimethylarsonium compounds） that are found in foods and consider their origins,metabolism, and potential toxicity. Commonalities in the metabolism of arsenosugars and arsenolipids lead to the production of di-methylated arsenicals which are known to exert many toxic effects. Evaluating foods as sources of exposure to these complex organic arsenicals and understanding the formation of reactive metabolites may be critical in assessing their contribution to aggregate exposure to arsenic.

关键词： Arsenic Arsenobetaine Arsenolipids Arsenosugars

Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第3期24卷 129-143页

作者： j.a-Qi Wang Xiao-j.n j.ang j.e Zheng Hanna Kellermann Arno Riffeser Liang Wang karen A.Collins Allyson Bieryla Lars A.Buchhave Steve B.Howell Elise Furlan Eric Girardin j.ao Gregorio Eric j.nsen Felipe Murgas Mesut Yilmaz Sam Quinn Xing Gao Ruo-Yu Zhou Frank Grupp Hui-j.an Wang CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy Of SciencesBeijing 10010China University of Chinese Academy of Sciences Beijing 100049China University Observatory Munich Scheinertrsse 1.D-81679 MunichGemany Max Planck Institute for Extraterrestrial Physics Giessenbachstr.1D-85748 GarchingGermany National Astronomical Observatories/Nanj.ng Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China Center for Astrophysics Harvard&Smithsonian60 Garden Street.CambridgeMA 02138USA National Space Institute Technical University of DenmarkElektrovejDK-2800 KgsLyngbyDenmark NASA Ames Research Center Moffett FieldCA 94035USA NASA Exoplanet Science Institute Caltech/IPACMail Code 100-221200 E.California Blvd.PasadenaCA91125USA Grand Pra Observatory Switzerland Department of Physics Washington UniversitySt.LouisMO 63130.USA Department of Physics and Astronomy Swarthmore CollegeSwarthmorePA 19081USA Instituto de Astrofísica de Canarias(IAC) E-38205 La Laguna.TenerifeSpain Departamento de Astrofísica Universidad de La LagunaSpain Dept.of Astronomy and Space Sciences Ankara UniversityTandogan 06100AnkaraTurkey Xinj.ang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Urumqi No.1 Senior High School Urumqi 830002China Lij.ang Gemini Observatory Lijiang 674199China

We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(j.,and a very low mass companion star with a mass of about 96.5±1.5 Mj.TOI-1251 *** candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium *** analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Obj.cts of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period ***-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric *** measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041Rj.and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(j. and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1).

关键词： planets and satellites fundamental parameters-planets and satellites gaseous planets-stars fundamental parameters-stars low-mass-methods data analysis-techniques photometric-techniques spectroscopic

Rereading East Germany

在线全文

学校读者我要写书评

暂无评论

Rereading East Germany

Superior growth performance in broiler chicks fed chelated compared to inorganic zinc in presence of elevated dietary copper

作者： Leeder karen j.

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

j.urnal of Animal Science and Biotechnology 2016年第4期7卷 561-569页

作者： j.nmei Zhao Robert B. Shirley j.lia j. Dibner karen j. Wedekind Frances Yan Paula Fisher Thomas R. Hampton j.seph L. Evans Mercedes Vazquez-Anon research and development novus international20 Research Park DriveSaint CharlesMO 63304USA current affiliation:poultry technical services adisseo usaAlpharettaGA 30022USA

Background： The goal of this study was to compare the antagonism of elevated dietary Cu （250 mg/kg） from CuS04 on three different Zn sources （ZnS04. H20; [Zn bis（-2-hydroxy-4-（methylthio）butanoic acid）], Zn（HMTBa）2 a chelated Zn methionine hydroxy analogue; and Zn-Methionine）, as measured using multiple indices of animal performance in ROSS 308 broilers. Methods： Three experiments were conducted in broiler chicks fed a semi-purified diet. All birds were fed a Zn-deficient diet （8.5 mg/kg diet） for 1 wk, and then provided with the experimental diets for 2 wks. Results： Experiment 1 was a 2 x 2 factorial design with two levels of Cu （8 vs. 250 mg/kg diet from CuSO4） and two Zn sources at 30 mg/kg [ZnSO4. H20 vs. Zn（HMTBa）2]. Elevated Cu impaired growth performance only in birds fed ZnSO4. Compared to ZnSO4. H20, Zn（HMTBa）2 improved feed intake （12 %; P 〈 0.001） and weight gain （12 %, P 〈 0.001） and the benefits were more pronounced in the presence of 250 mg/kg diet Cu. Experiment 2 was a dose titration of ZnSO4- H20 and Zn（HMTBa）2 at 30, 4,5, 60, and 75 mg/kg diet in the presence of 250 mg/kg CuSO4. Feed：gain was decreased and tibia Zn was increased with increasing Zn levels from 30 to 75 mg/kg. Birds fed Zn（HMTBa）2 consumed more food and gained more weight compared to birds fed ZnSO4, especially at lower supplementation levels （30 and 45 mg/kg; interaction P 〈 0,05）. Experiment 3 compared two organic Zn sources （Zn（HMTBa）2 vs. Zn-Methionine） at 30 mg/kg with or without 250 mg/kg CuSO4. No interactions were observed between Zn sources and Cu levels on performance or tissue mineral concentrations. High dietary Cu decreased weight gain （P 〈 0.01）. Tibia Cu and liver Cu were significantly increased with 250 mg/kg dietary Cu supplementation （P 〈 0.01）. No difference was observed between the two Zn sources. Conclusions： Dietary 250 mg/kg Cu significantly impaired feed intake and weight gain in birds fed ZnSO4. H20, but had less impact in birds fed Zn（HMTBa）2. No difference

关键词： Antagonism Broilers Chelates Growth MineraLs Organic Performance