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Synthetic and Systems Biotechnology 2022年第2期7卷 671-682页

作者： Joshua C.Corpuz Javier O.Sanlley michael d.burkart department of Chemistry and Biochemistry University of California-San Diego9500 Gilman DriveLa JollaCA92093-0358USA

Non-ribosomal peptide synthetases(NRPSs)are attractive targets for biosynthetic pathway engineering due to their modular architecture and the therapeutic relevance of their *** catalysis mediated by specific protein-protein interactions formed between the peptidyl carrier protein(PCP)and its partner enzymes,NRPS enzymology and control remains fertile ground for *** review focuses on the recent efforts within structural biology by compiling high-resolution structural data that shed light into the various protein-protein interfaces formed between the PCP and its partner enzymes,including the phosphopantetheinyl transferase(PPTase),adenylation(A)domain,condensation(C)domain,thioesterase(TE)domain and other tailoring enzymes within the *** our understanding of how the PCP recognizes partner proteins with the potential to use directed evolution and combinatorial biosynthetic methods will enhance future efforts in discovery and production of new bioactive compounds.

关键词： Natural products Protein-protein interactions Non-ribosomal peptide synthetase Peptidyl carrier protein Combinatorial biosynthesis Synthetic biology

Peroxidase-Like Reactivity at Iron-Chelation Sites in a Mesoporous Synthetic Melanin

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CCS Chemistry 2021年第3期3卷 1483-1490页

作者： Yijun Xie Kelsey A.Krug Kristine S.Cay Mark Kalaj Naneki C.McCallum Zofia E.Siwicka Zhao Wang Nathan C.Gianneschi michael d.burkart Jeffrey d.Rinehart Materials Science and Engineering Program University of CaliforniaSan DiegoLa JollaCA 92093 department of Chemistry and Biochemistry University of CaliforniaSan DiegoLa JollaCA 92093 department of Chemistry Northwestern UniversityEvanstonIL 60208 International Institute of Nanotechnology Simpson-Querrey InstituteChemistry of Life Processes InstituteNorthwestern UniversityEvanstonIL 60208 Pritzker School of Molecular Engineering University of ChicagoChicagoIL 60637 Lurie Cancer Center Northwestern UniversityEvanstonIL 60208 department of Materials Sciences and Engineering Northwestern UniversityEvanstonIL 60208 department of Biomedical Engineering Northwestern UniversityEvanstonIL 60208

High catalytic activity and substrate specificity make enzymes a rich source of inspiration for catalyst ***-opting the advantages of natural materials while tuning them to a modified form and purpose,however,is not a straightforward synthetic *** of L-3,4-dihydroxyphenylalanine(L-dOPA)results in amorphous polymer nanoparticles that are similar in many ways to natural ***,the authors introduce mesoporosity and iron ion chelation to synthesize a variant of the L-dOPA polymer with high peroxidase-like *** results indicate catalytic reaction with peroxide under mildly acidic conditions(pH 5.4 and 6)with a greater maximum reaction velocity(Vmax)than horseradish peroxidase(HRP)at optimal pH 3.5–*** between Fe(Ⅲ)and Fe(Ⅱ)loading indicates that either can be used as a starting point to trigger reactivity,though Fe(Ⅱ)loading leads to materials with twice the Vmax of the Fe(Ⅲ)-loaded *** lack of catalyst degradation despite the redox changes and presence of radical species is consistent with the robust nature and redox versatility of polydopamine-based materials and demonstrates strong potential as a versatile redox-catalysis platform.

关键词： L-dOPA mesoporosity peroxidase-like reactivity iron ion chelation catalysis

Microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in Manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan Zhang michael d.Gilchrist School of Mechanical and Materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2d computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： Micro feature shaping and electropolishing Micro mould tools Green electrolyte demoulding micro patterns

BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

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Neural Regeneration Research 2024年第2期19卷 447-457页

作者： michael W.Weible II michael d.Lovelace Hamish d.Mundell Tsz Wai Rosita Pang Tailoi Chan-Ling Bosch Institute Discipline of Anatomy and Histology(F13)University of SydneySydneyNSWAustralia School of Environment and Science Griffith UniversityNathanQLDAustralia discipline of Medicine Nepean Clinical SchoolFaculty of Medicine and HealthUniversity of SydneyKingswoodNSWAustralia New South Wales Brain Tissue Resource Centre School of Medical SciencesFaculty of Medicine and HealthUniversity of SydneyCharles Perkins Centre(D17)SydneyNSWAustralia

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well ***-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is *** was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory *** and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,Cd34/*** immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/Cd118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,*** neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent *** cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage ***-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in *** is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal *** data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterize

关键词： BMPRⅡ bone morphogenetic protein histotypic human spinal cord development leukemia inhibitory factor neurosphere organotypic reaggregate sensory columns

Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: detailed structural investigation

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Nano Research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion *** separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent *** patterns produced had long-range order and domain sizes>1μ*** BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP *** ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room *** oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide *** mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate *** formation and stability of the sulphide nanowires were studied at different *** photoluminescence and Raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence

Injury and illness in short-course triathletes:A systematic review

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Journal of Sport and Health Science 2024年第2期13卷 172-185页

作者： Sara A.Guevara Melissa L.Crunkhorn michael drew Gordon Waddington Julien d.Périard Naroa Etxebarria Liam A.Toohey Paula Charlton University of Canberra Research Institute for Sport and Exercise(UCRISE) BruceACT 2617Australia New South Wales Institute of Sport SydneyNSW 2127Australia Queensland Academy of Sport BrisbaneQLD 4111Australia Triathlon Australia Gold CoastQLD 4227Australia Australian Institute of Sport BruceACT 2617Australia

Background:determining the incidence and prevalence of injury and illness in short-course triathletes would improve understanding of their etiologies and therefore assist in the development and implementation of prevention *** study synthesizes the existing evidence on the incidence and prevalence of injury and illness and summarizes reported injury or illness etiology and risk factors affecting short-course ***:This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** reporting health problems(injury and illness)in triathletes(all sexes,ages,and experience levels)training and/or competing in short-course distances were *** electronic databases(Cochrane Central Register of Controlled Trials,MEdLINE,Embase,APA PsychINFO,Web of Science Core Collection,and SPORTdiscus)were *** of bias was independently assessed by 2 reviewers using the Newcastle-Ottawa Quality Assessment *** authors independently completed data ***:The search yielded 7998 studies,with 42 studies eligible for ***-three studies investigated injuries,24 studies investigated illnesses,and 5 studies investigated both injuries and *** injury incidence rate ranged 15.7-24.3 per 1000 athlete exposures,and the illness incidence rate ranged 1.8-13.1 per 1000 athlete *** and illness prevalence ranged between 2%-15%and 6%-84%,*** injuries reported occurred during running(45%-92%),and the most frequently reported illnesses affected the gastrointestinal(7%-70%),cardiovascular(14%-59%),and respiratory systems(5%-60%).Conclusion:The most frequently reported health problems in short-course triathletes were:overuse and lower limb injuries associated with running;gastrointestinal illnesses and altered cardiac function,primarily attributable to environmental factors;and respiratory illness mostly caused by infection.

关键词： Athlete illnesses Athletic injuries Epidemiology Triathlon

Phrenic nerve block: the key to managing acute biliary pain?

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World Journal of Emergency Medicine 2024年第1期15卷 62-63页

作者： michael Shalaby Joshua Luftig department of Emergency Medicine and Critical Care Herbert Wertheim College of Medicine at Florida International UniversityMiami 33199USA Advanced Emergency Ultrasound Mount Sinai Medical CenterMiami Beach 33140USA department of Emergency Medicine Highland HospitalAlameda Health SystemOakland 94602USA

Over the past two decades,the USA has witnessed a steep rise in the incidence of acute cholecystitis(AC),[1]even among children,[2]with over 200,000 cases annually.[3]Patients with AC often present to the emergency department(Ed)experiencing severe distress,with most describing their pain level as“intolerable.”[4]Furthermore,there is usually a considerable delay before surgery,with a median time from diagnosis of AC to surgery of 28.5 h,[5]and a substantial percentage of patients wait as long as 10 d.[6]Prolonged delays before surgery lead to increased opioid use,which is associated with extended hospital stays and higher rates of readmission after cholecystectomy.[7]Furthermore,opioids can lead to vomiting,respiratory depression,delirium,and ultimately addiction.[8]We propose a novel regional anesthesia technique for managing AC:right phrenic nerve *** method could offer improved pain control and a more favorable risk profile in selected patients when compared to current Ed practices.

关键词： pain anesthesia diagnosis

diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： Christian Herder michael Roden Nicolas Venteclef Institute for Clinical diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany German Center for diabetes Research(dZd) Partner Düsseldorf85764München-NeuherbergGermany department of Endocrinology and diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-Enfants Malades(INEM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory *** analyses revealed a central role of lung dendritic cells(dC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory

Multiple sclerosis drug repurposing for neuroregeneration

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Neural Regeneration Research 2024年第3期19卷 507-508页

作者： Peter Göttle michael dietrich Patrick Küry department of Neurology Medical FacultyHeinrich-Heine UniversityDüsseldorfGermany

Multiple sclerosis(MS)is an autoimmune disorder of the central nervous system(CNS)and is primarily characterized by immune cell infiltration leading to relapses followed by remission phases and a disease course turning progressive over time with neurodegenerative processes taking over(Amin and Hersh,2023).Of note,beyond relapse-associated worsening early in disease progression independent of relapse activity may arise independently of relapse activity and can occur in all ***-mediated damage of myelin sheaths and the subsequent loss of mature oligodendrocytes are resulting in impaired axonal integrity,neurodegeneration and accounts for irreversible neuronal damage(Kuhlmann et al.,2023).The current landscape of available disease-modifying therapies comprises mainly immunomodulatory drugs that effectively diminish relapses and slow down progression at the onset form of the disease,namely relapsing MS(RMS).In this regard,a number of drugs have been approved as disease-modifying therapies for MS by US Food and drug Administration and European Medicines Agencies(Box 1).

关键词： drugs impaired irreversible

Water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第1期13卷 217-236页

作者： Matthew L.Skoog michael A.Eggleton Yushun Chen department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota department of Natural Resources State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P differences between agriculture and forest streams with respect to other physical and chemical variables were intermittent and season dependent. Fish assemblages in agriculture and forest streams were structured primarily along an environmental gradient reflecting instream habitat conditions, water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use Water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain