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Efficient HIV-1 in vitro reverse transcription: optimal capsid stability is required

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Signal Transduction and Targeted Therapy 2021年第2期6卷 195-196页

作者： ryan c.Burdick Vinay K.Pathak Viral Mutation Section HIV Dynamics and Replication ProgramCenter for Cancer ResearchNational Cancer Institute at FrederickFrederickMD 21702USA

Recently,christensen et *** HIV-1 reverse transcription and integration in a cell-free system and found that viral double-stranded DNA that is capable of integration into a target plasmid DNA was efficiently synthesized within viral cores,indicating that the capsid protein shell plays an important role in viral genome replication.1 HIV-1 reverse transcriptase(RT)copies the viral genomic RNA into a double-stranded DNA,and HIV-1 integrase(IN)inserts the viral DNA into the host genome to form a *** RT and IN have been successfully targeted with potent antiretroviral drugs to inhibit these enzymes and treat patients infected with HIV-1,the causative agent of acquired immunodeficiency syndrome(AIDS).Despite decades of research,the molecular mechanisms of reverse transcription and integration in vivo are not fully characterized,in part because cell-free assays that efficiently and faithfully recapitulate the processes in the context of a virion have not been available。

关键词： al. drugs optimal

cretaceous Hitchhikers:a Possible Phoretic Association between a Pseudoscorpion and Bird in Burmese Amber

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2434-2435页

作者： XING Lida ryan c.McKELLAR. GAO Zhizhong State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China School of the Earth Sciences and Resourees China University of GeosciencesBeijing 100083China Royal Saskatchewan Museum ReginaSaskatchewan S4P 4W7Canada Biology Department University of ReginaReginaSaskatchewan S4S OA2Canada Department of Ecology and Evolutionary Biology University of KansasLawrenceKansas66405USA Department of Biology Xinzhou Teachers UniversityXinzhou 034000ShanxiChina

Objective Phoresy represents a non-parasitic association between animals of different taxa related to transportation. Members of several pseudoscorpion families are phoretic. In pseudoscorpions, phoresy may or may not be associated with their predatory behavior, enabling dispersal over larger distances than they could manage with their own short legs. This provides a wide distribution, and a potential food supply.

关键词： cretaceous Hitchhikers a Possible Phoretic Association between a Pseudoscorpion and Bird in Burmese Amber DIP

A WEPp-Water Quality model for simulating nonpoint source pollutants in nonuniform agricultural hillslopes:Model development and sensitivity

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International Soil and Water conservation Research 2023年第3期11卷 455-469页

作者： ryan PMcGehee Dennis cFlanagan Bernard AEngel Department of Agricultural and Biological Engineering Purdue University225 South University StreetWest LafayetteIN47907USA DA-Agricultural Research Service National SoilErosion Research Laboratory275 South Russell StreetWest LafayetteIN4797USA

The Water Erosion Prediction Project(WEPP)model code was modified extensively to support the simulation of nonpoint source(NPS)pollutant sourcing and transport in nonuniform hillslopes based on NPS science from the Soil and Water Assessment Tool(SWAT).This was accomplished utilizing WEPP's overland flow element(OFE)in place of SWAT's hydrologic response unit(HRU)construct which enabled more physically plausible routing within a *** addition,several improvements to the NPS code base were *** include:free-source format,modern-Fortran conventions,minor enhancements to NPS model science,and code *** manuscript documents all model development activities,presents a comparison of relevant WEPP and WEPP-WQ code bases,and performs a local sensitivity analysis of the final model code for the most important input parameters and *** results indicated that the model performed as expected according to its design and provided important insights for potential subsequent validation studies.

关键词： WEPP SWAT WEPP-WQ Water quality Nonpoint Sensitivity

Ground control monitoring of retreat room–and–pillar mine in central Appalachia

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International Journal of Mining Science and Technology 2017年第1期27卷 65-69页

作者： Erik c.Westman ryan J.Molka William J.conrad Mining and Minerals Engineering Department Virginia TechBlacksburgVA 24061USA

In order to study pillar and overburden response to retreat mining, a ground control program was conducted at a central Appalachian Mine. The program consisted of several monitoring methods including a seismic monitoring system, borehole pressure cells in the pillars, and time-lapse photogrammetry of the pillar ribs. Two parallel geophone arrays were installed, one on each side of the panel with the sensors mounted 3 m into the roof. A total of fourteen geophones recorded more than 5000 events during the panel retreat. A MIDAS datalogger was used to record pressure from borehole pressure cells(BPcs)located in two adjacent pillars that were not mined during retreat. A series of photographs were taken of the pillars that had the BPcs as the face approached so that deformation of the entire rib could be monitored using photogrammetry. Results showed that pillar stability and cave development were as expected. The BPcs showed an increase in loading when the face was 115 m inby and a clear onset of the forward abutment at 30 m. The photogrammetry results displayed pillar deformation corresponding to the increased loading. The microseismic monitoring results showed the overburden caving inby the face, again as expected. The significance of these results lies in two points,(1) we can quantify the safe manner in which this mine is conducting retreating operations, and(2) we can use volumetric technologies(photogrammetry and microseismic) to monitor entire volumes of the mine in addition to the traditional point-location geotechnical measurements(BPcs).

关键词： Retreat mining Stress measurement Microseismic monitoring Pillar stability

The significance of clinical practice guidelines on adult varicocele detection and management

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Asian Journal of Andrology 2016年第2期18卷 269-275,J0006,J0007页

作者： Anand Shridharani ryan c Owen Osama O Elkelany Edward D Kim Department of Urology University of Tennessee College of Medicine Chattanooga TN 37403 USA Division of Urology Department of Surgery University of Tennessee Graduate School of Medicine Knoxville TN 37920 USA.

Varicoceles are the most common correctable etiology of male factor infertility. However, the detection and management of varicoceles have not been standardized. This has led to decades of debate regarding the effect of varicocele on male infertility and subsequently whether repair leads to an improved fertility status. The current body of evidence investigating the role of varicocele and varicocelectomy is weak and conflicting. The stance taken by the AUA and ASRM suggests that there is insufficient outcomes data to support evidenced-based guidelines, citing evidence used to provide current recommendations are generally of a low quality level. On the other hand, the EAU Guidelines give a level la of evidence for management of varicoceles that are clinically palpable, associated with subnormal semen analyses and having otherwise unexplained fertility. Besides aiding with clinical varicocele detection and management, clinical practice opinion statements and guidelines aim to direct and strengthen the infrastructure of future studies. We review the current status of opinion statements and guidelines in varicocele and management detection with focus on their application in practice.

关键词： guidelines varicocele varicocele detection varicocele management varicocelectomy

Nexus between polymer support and metal oxide nanoparticles in hybrid nanosorbent materials （HNMs） for sorption/desorption of target ligands

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 929-938页

作者： ryan c. SMITH Jinze LI Surapol PADUNGTHON Arup K. SENGUPTA Environmental Engineering Program Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

Metal oxide nanoparticles like hydrated ferric oxide （HFO） or hydrated zirconium oxide （HZrO） are excellent sorbents for environmentally significant ligands like phosphate, arsenic, or fluoride, present at trace concentrations. Since the sorption capacity is surface dependent for HFO and HZrO, nanoscale sizes offer significant enhancement in performance. However, due to their miniscule sizes, low attrition resistance, and poor durability they are unable to be used in typical plug-flow column setups. Meanwhile ion exchange resins, which have no specific affinity toward anionic ligands, are durable and chemically stable. By impregnating metal oxide nanoparticles inside a polymer support, with or without functional groups, a hybrid nanosorbent material （HNM） can be prepared. A HNM is durable, mechanically strong, and chemically stable. The functional groups of the polymeric support will affect the overall removal effi- ciency of the ligands exerted by the Donnan Membrane Effect. For example, the removal of arsenic by HFO or the removal of fluoride by HZrO is enhanced by using anion exchange resins. The HNM can be precisely tuned to remove one type of contaminant over another type. Also, the physical morphology of the support material, spherical bead versus ion exchange fiber, has a significant effect on kinetics of sorption and desorption. HNMs also possess dual sorption sites and are capable of removing multiple contaminants, namely, arsenate and perchlorate, concurrently.

关键词： ion exchange sorpfion arsenic perchlorat~,fluoride

TLR2 and TLR4 in Parkinson’s disease pathogenesis:the environment takes a toll on the gut

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Translational Neurodegeneration 2021年第4期10卷 611-629页

作者： Anastazja M.Gorecki chidozie c.Anyaegbu ryan S.Anderton School of Biological Science University of Western AustraliaCrawleyWAAustralia Neurodegenerative Disorders Research Group Perron Institute for Neurological and Translational ScienceNedlandsWAAustralia curtin Health Innovation Research Institute Ralph and Patricia Sarich Neuroscience Research InstituteCurtin UniversityNedlandsWAAustralia Faculty of Medicine Nursing and Midwifery and Faculty of Health SciencesUniversity of Notre Dame AustraliaFremantleWAAustralia School of Nursing MidwiferyHealth Sciences and PhysiotherapyUniversity of Notre Dame AustraliaFremantleWAAustralia

Parkinson's disease(PD)is an incurable,devastating disorder that is characterized by pathological protein aggregation and neurodegeneration in the substantia *** recent years,growing evidence has implicated the gut environment and the gut-brain axis in the pathogenesis and progression of PD,especially in a subset of people who exhibit prodromal gastrointestinal ***,perturbations of gut homeostasis are hypothesized to contribute toα-synuclein aggregation in enteric neurons,which may spread to the brain over decades and eventually result in the characteristic central nervous system manifestations of PD,including neurodegeneration and motor ***,the mechanisms linking gut disturbances andα-synuclein aggregation are still unclear.A plethora of research indicates that toll-like receptors(TLRs),especially TLR2 and TLR4;are critical mediators of gut *** their established role in innate immunity throughout the body,studies are increasingly demonstrating that TLR2 and TLR4 signalling shapes the development and function of the gut and the enteric nervous ***,TLR2 and TLR4 are dysregulated in patients with PD,and may thus be central to early gut dysfunction in *** better understand the putative contribution of intestinal TLR2 and TLR4 dysfunction to earlyα-synuclein aggregation and PD,we critically discuss the role of TLR2 and TLR4 in normal gut function as well as evidence for altered TLR2 and TLR4 signalling in PD;by reviewing clinical,animal model and in vitro *** evidence on the immunological aetiology ofα-synuclein aggregation is also discussed,with a focus on the interactions ofα-synuclein with TLR2 and *** propose a conceptual model of PD pathogenesis in which microbial dysbiosis alters the permeability of the intestinal barrier as well as TLR2 and TLR4 signalling,ultimately leading to a positive feedback loop of chronic gut dysfunction promotingα-synuclein aggregation in enteric an

关键词： Parkinson’s disease TLR2 TLR4 α-Synuclein Gut-brain axis Gut barrier Gut homeostasis

calibration,validation,and evaluation of the Water Erosion Prediction Project(WEPP)model for hillslopes with natural runoff plot data

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International Soil and Water conservation Research 2023年第4期11卷 669-687页

作者： Shuyuan Wang ryan P.McGehee Tian Guo Dennis c.Flanagan Bernard A.Engel Department of Agricultural&Biological Engineering Purdue UniversityWest LafayetteIN47907USA USDA-Agricultural Research Service National Soil Erosion Research LaboratoryWest LafayetteIN47907USA

The Water Erosion Prediction Project(WEPP)model has been widely used for estimating runoff and soil *** evaluation of the latest version(version 2021.133)under a range of environmental conditions can provide confidence to its *** objectives of this study were to evaluate the WEPP model for runoff and soil loss predictions using 1159 plot years of rainfall-runoff events data from field experi-mental plots with various climates,soils,topographies,and *** runoff and soil loss predictions were compared to the observations before and after input parameter *** results showed good predictions of runoff and soil loss were obtained with both the uncalibrated and calibrated WEPP model for all considered scales with Nash-Sutcliffe model efficiencies(NSE)over *** calibration of input baseline effective hydraulic conductivity(k_(e)),baseline critical shear stress(τ_(c)),baseline rill erod-ibility(k_(r)),and baseline interrill erodibility(k_(i))improved WEPP model performance with NSE values of 0.98 and 0.91 for average annual runoff and soil loss predictions,*** WEPP model tended to underestimate the runoff and soil loss for large events with runoff over 100 mm and soil loss over 120t/*** event runoff and soil loss predictions(NSE ≥0.4)were obtained for the most common cropping/management systems considered,including corn,cotton,tilled fallow,and wheat after *** study illustrates the most recent WEPP model's performance for runoff and soil loss predictions,and provides a comprehensive set of results.

关键词： WEPP Runoff Soil loss calibration Validation

In vivo radiometric analysis of glucose uptake and distribution in mouse bone

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Bone Research 2016年第1期4卷 31-38页

作者： Meredith L Zoch Diane S Abou Thomas L clemens Daniel LJ Thorek ryan c Riddle Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Baltimore USA Division of Nuclear Medicine an Molecular Imaging Department of Radiology and Radiological Science Johns Hopkins University School of Medicine Baltimore USA Baltimore Veterans Administration Medical center Baltimore USA Department of Oncology Cancer Molecular and Functional Imaging Program Sidney Kimmel Comprehensive Cancer Center Johns Hopkins University School of Medicine Baltimore USA

Bone formation and remodeling occurs throughout life and requires the sustained activity of osteoblasts and osteoclasts, particularly during periods of rapid bone growth. Despite increasing evidence linking bone cell activity to global energy homeostasis, little is known about the relative energy requirements or substrate utilization of bone cells. In these studies, we measured the uptake and distribution of glucose in the skeleton in vivo using positron-emitting 18F-fluorodeoxyglucose （[lSF]-FDG） and non-invasive, high-resolution positron emission tomography/computed tomography （PE~/cT） imaging and ex vivo autoradiography. Assessment of [~SF]-FDG uptake demonstrated that relative to other tissues bone accumulated a significant fraction of the total dose of the glucose analog..Skeletal accumulation was greatest in young mice undergoing the rapid bone formation that characterizes early development. PET/cT imaging revealed that [lSF]-FDG uptake was greatest in the epiphyseal and metaphyseal regions of long bones, which accords with the increased osteoblast numbers and activity at this skeletal site. Insulin administration significantly increased skeletal accumulation of [lSF]-FDG, while uptake was reduced in mice lacking the insulin receptor specifically in osteoblasts or fed a high-fat diet. Our results indicated that the skeleton is a site of significant glucose uptake and that its consumption by bone cells is subject to regulation by insulin and disturbances in whole-body metabolism.

关键词： bone FDG