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Claudin-11 and occludin are major contributors to Sertoli cell tight junction function, in vitro

Asian journal of Andrology 2016年第4期18卷 620-626页

作者： mark j McCabe Caroline FH Foo Marcel E Dinger Peter M Smooker Peter G Stanton Male Fertility Regulation Laboratory Hudson Institute of Medical Research Monash Medical Centre Clayton Victoria 3168 Australia School of Applied Sciences Royal Melbourne Institute of Technology University Bundoora Victoria 3088 Australia Kinghorn Centre for Clinical Genomics Garvan Institute of Medical Research Darlinghurst New South Wales 2010 Australia St Vincent's Clinical School UNSW Sydney New South Wales 2052 Australia.

The Sertoli cell tight junction （T j） is the key component of the blood-testis barrier, where it sequesters developing germ cells undergoing spermatogenesis within the seminiferous tubules. Hormonally regulated claudin-11 is a critical transmembrane protein involved in barrier function and its murine knockout results in infertility. We aimed to assess quantitatively the significance of the contribution of claudin-11 to Tj function, in vitro, using siRNA-mediated gene silencing. We also conducted an analysis of the contribution of occludin, another intrinsic transmembrane protein of the Tj. Silencing of claudin-11 and/or occludin was conducted using siRNA in an immature rat Sertoli cell culture model. Transepithelial electrical resistance was used to assess quantitatively Tj function throughout the culture. Two days after siRNA treatment, cells were fixed for immunocytochemical localization of junction proteins or lyzed for RT-PCR assessment of mRNA expression. Silencing of claudin-11, occludin, or both resulted in significant decreases in Tj function of 55% （P 〈 0.01）, 51% （P 〈 0.01）, and 62% （P 〈 0.01）, respectively. Data were concomitant with significant decreases in mRNA expression and marked reductions in the localization of targeted proteins to the Sertoli cell Tj. We provide quantitative evidence that claudin-11 contributes significantly （P 〈 0.01） to Sertoli cell Tj function in vitro. Interestingly, occludin, which is hormonally regulated but not implicated in infertility until late adulthood, is also a significant （P 〈 0.01） contributor to barrier function. Our data are consistent with in vivo studies that clearly demonstrate a role for these proteins in maintaining normal Tj barrier structure and function.

关键词： blood-testis barrier claudin-11 occludin Sertoli cell tight junction siRNA

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Oxidative stress and male reproductive health

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Asian journal of Andrology 2014年第1期16卷 31-38页

作者： Robert j Aitken Tegan B Smith Matthew S jobling mark A Baker Geoffry N De Iuliis Priority Research Centre in Reproductive Science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair （BER） pathway, 8-oxoguanine glycosylase 1 （OGG1）. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa

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Hydrologic Modeling Impacts of post-mining Land Use Changes on Streamflow of Peace River, Florida

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Chinese Geographical Science 2015年第6期25卷 728-738页

作者： ZHANG jing mark ROSS Key Laboratory of Resource Environment and GIS in Beijing Capital Normal University Department of Civil and Environmental Engineering University of South Florida

Whether mining activity results in reduced flow of surface water in the Peace River Watershed of Florida has been the subject of much debate. With increased dependence of downstream users on surface water flow of the Peace River as a source of drinking water for four coastal counties in Southwest Florida and problems of water security, the debate has been intensified. It is possible to assess relationships of mining with streamflow in the upper reaches of the Peace River Basin using hydrologic modeling and identify mined sub-basins. In this work, land-use change impacts were simulated by the Hydrological Simulation Program--Fortran （HSPF） model based on geographical information system （GIS） tools, to compare pre- and post-mining streamflows at a study site of the Peace River in west-central Florida. The purpose of this study was to determine if land-use changes caused by mining have negatively impacted streamflow in the Peace River. Changes of land use were identified before and after mining activities. A coupled volume-water depth-discharge （V-h-Q） model based on stage/storage and stage/discharge was applied using HSPF for the pre-mining and post-mining models, respectively. Daily simulated post-mining hydrographs from HSPF were plotted with the calibrated pre-mining results and streamflow hydrographs from the 18 gauging stations, to compare timing of peaks, low fows and flow trends. Analyses of percent ex- ceedances of flow frequency curves of the streams indicated that most streams had similar distributions for mined （reclaimed） and pre- mining periods. In the streamflow change analysis, streamflows actually increased in mining-affected basins at nearly half the stations. Streamflows at other stations diminished. Overall from this comprehensive study, there were declines in streamflow at most gauging stations on the mainstem of the Peace River and its tributaries. The results of this study suggest that regional planning is urgently needed to propose reclamation s

关键词： post-mining land-use changes streamflow hydrologic model Hydrological Simulation Program--Fortran (HSPF) model

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The role of latitudinal, genetic and temperature variation in the induction of diapause of Papilio glaucus （Lepidoptera： Papilionidae）

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Insect Science 2018年第2期25卷 328-336页

作者： Sean F. Ryan Patti Valella Gabrielle Thivierge Matthew L. Aardema j. mark Scriber Department of Biological Sciences University of Notre Dame Notre Dame Indiana USA USDA-ARS Center for Medical Agricultural and Veterinary Entomology 1600/1700 Southwest 23rd Drive Gainesville Florida USA Department of Entomology Michigan State University East Lansing Michigan USA Life Science Department Long Beach City College Long Beach California USA Sackler Institute for Comparative Genomics American Museum of Natural History New York New York USA McGuire Centerfor Lepidoptera and Diversity University of Florida Gainesville Florida US

A key adaptation in insects for dealing with variable environmental conditions is the ability to diapause. The tiger swallowtail butterflies, Papilio glaucus and P. canadensis are ideal species to explore the genetic causes and population genetic consequences of diapause because divergence in this trait is believed to be a salient factor in maintaining a hybrid zone between these species. Yet little is known about the factors that influence diapause induction in this system. Here we explored how spatial （latitudinal）, environmental （temperature） and genetic （hybridization） factors affect diapause induction in this system. Specifically, a series of growth chamber experiments using wild caught individuals from across the eastern United States were performed to：（1） evaluate how critical photoperiod varies with latitude, （2） isolate the stage in which induction occurs, （3） test whether changes in temperature affected rates of diapause induction, and （4） explore how the incidence of diapause is affected in hybrid offspring. We find that induction occurs in the larval stage, is not sensitive to a relatively broad range of temperatures, appears to have a complex genetic basis （i.e., is not simply a dominant trait following a Mendelian inheritance pattern） and that the critical photoperiod increases by 0.4 h with each increasing degree in latitude. This work deepens our understanding of how spatial, environmental and genetic variation influences a key seasonal adaptation （diapause induction） in a well-developed ecological model system and will make possible future studies that explore how climatic variation affects the population dynamics and genetics of this system.

关键词： adaptation critical photoperiod development diapauses facultative hybridization

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Do introduced honeybees affect seed set and seed quality in a plant adapted for bird pollination?

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journal of Plant Ecology 2017年第4期10卷 721-729页

作者： Amy-Marie Gilpin justin C.Collette Andrew j.Denham mark K.j.Ooi David j.Ayre Centre for Sustainable Ecosystem Solutions School of Biological SciencesUniversity of WollongongNorthfields AvenueWollongongNSW 2522Australia NSW Department of Premier and Cabinet Office of Environment and HeritagePO Box 1967HurstvilleNSW 2220Australia Centre for Ecosystem Science School of BiologicalEarth and Environmental SciencesUniversity of New South WalesSydneyNSW 2052Australia

Aims Worldwide,evidence suggests that exotic pollinators can disrupt plant mating ***,few studies have determined if pol-lination by the honeybee Apis mellifera(the world’s most widely introduced pollinator)reduces offspring quality when compared with pollination by native *** Australian Proteaceae provides an excellent opportunity to test the impact of honeybees in pol-lination systems that are adapted to birds and non-flying *** We compared the frequency of flower visitation and foraging behav-iour of birds and insects within seven populations of Banksia *** ericifolia is hermaphroditic and has large nectar-rich,orange inflorescences typical of bird and mammal pollinated *** a subset of the study populations,we compared the qual-ity of seed produced via an exclusion treatment(that only allowed invertebrates to access flowers)with an open-pollination treatment(potentially visited by mammals,birds and invertebrates),by meas-uring seed weight,germination rates(T50),percent germination,seedling height after 14 days since the emergence of the cotyledon and time to emergence of the *** Findings Apis mellifera was the only apparent insect pollinator and the most frequent flower visitor,while the open treatment inflorescences were also frequently visited by avian pollinators,primarily hone-yeater *** foraging behaviour of honeybees and honeyeat-ers showed striking differences that potentially affect patterns of pollen *** made significantly greater proportions of within *** plant movements and only 30%(n=48)of honeybees foraged for pollen(nectar foragers carried no pollen)whilst all birds were observed to contact both stigmas and anthers when foraging for *** these fundamental differences in behaviour,there was little effect of treatment on seed set or *** data show that while honeybees appear to alter patterns of pollen transfer within *** popu

关键词： Apis mellifera Banksia ericifolia Proteaceae seedling performance seed vigour

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Ipilimumab associated colitis: An Ipi Colitis case series at Med Star Georgetown University Hospital

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World journal of Gastroenterology 2015年第14期21卷 4373-4378页

作者： Pawan Rastogi Mohamed Sultan Aline j Charabaty Michael B Atkins mark C Mattar Department of Medicine MedS tar Georgetown University Hospital Department of Gastroenterology MedS tar Georgetown University Hospital Department of Oncology Georgetown Lombardi Comprehensive Cancer Center

Although ipilimumab has been shown to improve survival in patients with metastatic melanoma and cause regression of metastatic renal cell carcinoma, the associated immune-related toxicities are of *** resultant T cell activation by this monoclonal antibody causes an increased immune response, which has been associated with many immune-regulated adverse *** of the most concerning effects is the development of *** to 8% of patients have been reported to develop colitis, with 5% being severe(Grades 3-4).While initial treatment of such adverse effects is generally comprised of supportive and symptomatic treatment, more severe cases warrant the use of high dose ***, use of anti-TNF agents is usually reserved for those cases that prove to be refractory to *** describe a systematic case review of seven patients who developed gastrointestinal symptoms following initiation of ipilimumab immunotherapy, and present the steps in their evaluation, treatment and outcomes at our institution.

关键词： Colitis Ipilimumab Immunology Infliximab Immune-re

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Validity of a noninvasive estimation of deep body temperature when wearing personal protective equipment during exercise and recovery

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Military Medical Research 2019年第4期6卷 328-339页

作者： Andrew P.Hunt mark j.Buller Matthew j.Maley joseph T.Costello Ian B.Stewart School of Exercise and Nutrition Sciences&Institute of Health and Biomedical Innovation Queensland University of TechnologyBrisbaneQLDAustralia United States Army Research Institute of Environmental Medicine NatickMAUSA Extreme Environments Laboratory Department of Sport and Exercise ScienceUniversity of PortsmouthPortsmouthUK

Background:Deep body temperature is a critical indicator of heat ***,direct measures are often invasive,costly,and difficult to implement in the *** study assessed the agreement between deep body temperature estimated from heart rate and that measured directly during repeated work bouts while wearing explosive ordnance disposal(EOD)protective clothing and during ***:Eight males completed three work and recovery periods across two separate *** consisted of treadmill walking on a 1%incline at 2.5,4.0,or 5.5 km/h,in a random order,wearing EOD protective *** temperature and relative humidity were maintained at 24℃and 50%[Wet bulb globe temperature(WBGT)(20.9±1.2)℃]or 32℃and 60%[WBGT(29.0±0.2)℃]on the separate days,*** rate and gastrointestinal temperature(TGI)were monitored continuously,and deep body temperature was also estimated from heart rate(ECTemp).Results:The overall systematic bias between TGI and ECTemp was 0.01℃with 95%limits of agreement(Lo A)of±0.64℃and a root mean square error of 0.32℃.The average error statistics among participants showed no significant differences in error between the exercise and recovery periods or the environmental *** TGI levels of(37.0–37.5)℃,(37.5–38.0)℃,(38.0–38.5)℃,and>38.5℃,the systematic bias and±95%Lo A were(0.08±0.58)℃,(–0.02±0.69)℃,(–0.07±0.63)℃,and(–0.32±0.56)℃,***:The findings demonstrate acceptable validity of the ECTemp up to 38.5℃.Conducting work within an ECTemp limit of 38.4℃,in conditions similar to the present study,would protect the majority of personnel from an excessive elevation in deep body temperature(>39.0℃).

关键词： Protective clothing Body core temperature Heat strain Heat stress Kalman filter Explosive ordnance disposal

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Increased Incidence of Scarlet Fever--China,1999−2018

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China CDC weekly 2019年第5期1卷 63-66页

作者： Yuanhai You Ying Qin mark j.Walker Luzhao Feng jianzhong Zhang State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseaseNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Division of Infectious Diseases Chinese Center for Disease Control and PreventionBeijingChina School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre The University of QueenslandBrisbaneQLDAustralia.

What is already known about this topic?Scarlet fever had high incidence between the 1950s and 1980s,but during the 1980s and 1990s,the incidence of scarlet fever dropped to a relatively low and stable levels in *** is added by this report?Starting in 2011,scarlet fever incidence significantly increased in *** the eight years between 2011 and 2018,479,555 cases were reported,which exceeded the total number of 241,365 cases reported in the previous twelve years 1999–*** are the implications for public health practice?Both patient and pathogen epidemiological surveillance need to be heightened to monitor serious cases of scarlet fever and to implement timely control measures.

关键词： fever Fever Incidence

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A note on the estimation of variance for big BAF sampling

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Forest Ecosystems 2020年第4期7卷 819-832页

作者： jeffrey H.Gove Timothy G.Gregoire mark j.Ducey Thomas B.Lynch USDA Forest Service Northern Research Station271 Mast RoadDurham NH03824USA. School of Forestry&Environmental Studies Yale University360 Prospect StNew Haven CT06511USA. Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham NH03824USA. Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater OK74078USA.

Background:The double sampling method known as“big BAF sampling”has been advocated as a way to reduce sampling effort while still maintaining a reasonably precise estimate of volume.A well-known method for variance determination,Bruce’s method,is customarily used because the volume estimator takes the form of a product of random ***,the genesis of Bruce’s method is not known to most foresters who use the method in ***:We establish that the Taylor series approximation known as the Delta method provides a plausible explanation for the origins of Bruce’s *** were conducted on two different tree populations to ascertain the similarities of the Delta method to the exact variance of a ***,two alternative estimators for the variance of individual tree volume-basal area ratios,which are part of the estimation process,were compared within the overall variance estimation ***:The simulation results demonstrate that Bruce’s method provides a robust method for estimating the variance of inventories conducted with the big BAF *** simulations also demonstrate that the variance of the mean volume-basal area ratios can be computed using either the usual sample variance of the mean or the ratio variance estimators with equal accuracy,which had not been shown previously for Big BAF ***:A plausible explanation for the origins of Bruce’s method has been set forth both historically and mathematically in the Delta *** most settings,there is evidently no practical difference between applying the exact variance of a product or the Delta method—either can be used.A caution is articulated concerning the aggregation of tree-wise attributes into point-wise summaries in order to test the correlation between the two as a possible indicator of the need for further covariance augmentation.

关键词： Bitterlich sampling Delta method Double sampling Forest inventory Horizontal point sampling Variance of a product

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An approximate point-based alternative for the estimation of variance under big BAF sampling

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Forest Ecosystems 2021年第3期8卷 439-457页

作者： Thomas B.Lynch jeffrey H.Gove Timothy G.Gregoire mark j.Ducey Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA USDA Forest Service Northern Research Station271 Mast RoadDurham 03824NHUSA Yale School of Environment Yale University360 Prospect StNew Haven 06511CTUSA Department of Natural Resources and the Environment University of New Hampshire114 James HallDurham 03824NHUSA

Background:A new variance estimator is derived and tested for big BAF(Basal Area Factor)sampling which is a forest inventory system that utilizes Bitterlich sampling(point sampling)with two BAF sizes,a small BAF for tree counts and a larger BAF on which tree measurements are made usually including DBHs and heights needed for volume ***:The new estimator is derived using the Delta method from an existing formulation of the big BAF estimator as consisting of three sample *** new formula is compared to existing big BAF estimators including a popular estimator based on Bruce’s ***:Several computer simulation studies were conducted comparing the new variance estimator to all known variance estimators for big BAF currently in the forest inventory *** simulations the new estimator performed well and comparably to existing variance ***:A possible advantage of the new estimator is that it does not require the assumption of negligible correlation between basal area counts on the small BAF factor and volume-basal area ratios based on the large BAF factor selection trees,an assumption required by all previous big BAF variance estimation *** this correlation was negligible on the simulation stands used in this study,it is conceivable that the correlation could be significant in some forest types,such as those in which the DBH-height relationship can be affected substantially by density perhaps through *** derived a formula that can be used to estimate the covariance between estimates of mean basal area and the ratio of estimates of mean volume and mean basal *** also mathematically derived expressions for bias in the big BAF estimator that can be used to show the bias approaches zero in large samples on the order of 1n where n is the number of sample points.

关键词： Bitterlich sampling Delta method Double sampling Estimator bias Forest inventory Horizontal point sampling Variance of a product Volume basal area ratio Covariance estimation

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