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Heterozygous carriers of.galactocerebrosidase mutations that cause Krabbe disease have impaired microglial f.nction and def.ctive repair of.myelin damage

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Neural Regeneration Research 2018年第3期13卷 393-401页

作者： Nicole J.Scott-hewitt Christopher J.f.lts Mark D.Noble Department of.Biomedical Genetics University of Rochester School of Medicine and Dentistry

This review addresses two puzzling f.ndings related to mutations in galactocerebrosidase （GALC） that cause Krabbe disease （KD）, a severe lysosomal storage disorder characterized by extensive myelin damage in children with mutations in both GALC alleles. f.rst, heterozygous carriers of.KD-causing mutations, which include the biological parents of.children with KD, exhibit increased risk f.r developing other diseases. Second, variants in the GALC locus increase the risk of.developing multiple sclerosis （MS）, another disease characterized by extensive myelin damage. What explains these correlations？ In studies on cuprizone-induced myelin damage in heterozygous （GALC＋/–） mice carrying one copy of.a mutation that causes KD-like disease, the extent of.damage was similar in GALC＋/– and wild-type （WT） mice. In contrast, GALC＋/- mice had striking def.cts in repair of.cuprizone-induced damage. We f.rther f.und unexpected microglial def.cts in myelin debris clearance and in the ability to up-regulate the Trem2 microglial protein critical f.r debris uptake. These def.cts were rescued by exposure to a lysosomal re-acidif.ing drug discovered in our studies on KD, and which provides multiple clinically relevant benef.ts in the twitcher （GALC＋/–） mouse model of.KD. Thus, heterozygous GALC mutations cause ef.ects on biological f.nction that may help to understand the increased disease risk in heterozygous carriers of.such mutations and to understand why GALC variations increase the risk of.MS. Our f.ndings indicate that while some genetic risk f.ctors may contribute to complex diseases by increasing the risk of.tissue damage, others may do so by compromising tissue repair.

关键词： vulnerability locus multiple sclerosis Krabbe disease galactocerebrosidase microglia myelin repair lysosomal storage disorders heterozygous carriers Trem2 demyelination

脉宽调制变量控制喷头雾化性能及风洞环境雾滴沉积特性

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农业工程学报 2019年第3期35卷 42-51页

作者：张瑞瑞李龙龙付旺陈立平伊铜川唐青 Andrew J hewitt 北京农业智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 国家农业航空应用技术国际联合研究中心北京100097 西北农林科技大学机械与电子工程学院杨凌712100 昆士兰大学施药技术与安全研究中心

脉宽调制(pulse width modulation, PWM)技术是实现变量喷雾的重要手段,其工作参数与环境条件决定着施药的精准性。为探究PWM变量喷头雾化及风洞环境沉积特性,该文研制了脉宽调制变量喷雾系统,以农业施药常用空心圆锥雾化喷头喷雾的雾... 详细信息

脉宽调制(pulse width modulation, PWM)技术是实现变量喷雾的重要手段,其工作参数与环境条件决定着施药的精准性。为探究PWM变量喷头雾化及风洞环境沉积特性,该文研制了脉宽调制变量喷雾系统,以农业施药常用空心圆锥雾化喷头喷雾的雾化、沉积特性为研究对象,在IEA-II型常规风速风洞内,通过点阵式放置电容式雾滴沉积传感器测定计算雾滴沉积与沉积评价指数(deposition evaluation index,DEIX),并利用Spraytec雾滴粒径仪测试其雾滴体积中径(volume median diameter,VMD)和雾滴相对分布跨度(relative span,RS)。试验结果表明:占空比在10%～40%间,随占空比增大,雾滴体积中径呈减小趋势,与占空比10%时相比,占空比40%时的雾滴体积中径下降了7.9%;PWM占空比60%时分布跨度最小,较占空比20%时雾滴分布跨度下降9.52%,雾滴谱最窄,获得的雾滴粒径分布最集中。雾滴沉积方面,风速1 m/s条件下,雾滴主要沉积在距喷头3.3 m内,此范围内沉积量占总沉积量的95.7%,当风速超过3 m/s时,在气流作用下,雾滴沉降距离增大,导致雾滴运动偏离施药靶标区域。PWM占空比增加,雾滴沉积评价指数DEIX值降低,雾滴的飘移率增大;相同工况下,风速及喷头高度越大,DEIX越小,施药雾滴越易飘移。该研究可为农业田间实际生产中脉宽调制变量施药技术应用及其工况参数的选择提供依据,为PWM变量调节装置的进一步优化提供研究基础。

关键词：脉宽调制喷雾试验体积中径雾滴沉积评价指数风洞

SCNH2 is a novel apelinergic f.mily member acting as a potent mitogenic and chemotactic f.ctor f.r both endothelial and epithelial cells

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Open Journal of.Clinical Diagnostics 2013年第2期3卷 37-51页

作者： Changge f.ng Ingalill Avis Caterina Bianco Natalie Held Jennif.r Morris Kris Ylaya Stephen M. hewitt Alf.ed C. Aplin Roberto f. Nicosia Laura A. f.ng John D. Lewis William G. Stetler-Stevenson David S. Salomon f.ank Cuttitta Angiogenesis Core f.cility Radiation Oncology Branch Center for Cancer Research National Cancer Institute Bethesda USA Department of.Pathology University of Washington Seattle USA Department of.Pathology University of Washington Seattle USA Pathology and Laboratory Medicine Services Veterans Administration Puget Sound Health Care System Seattle USA Extracellular Matrix Pathology Section Radiation Oncology Branch Center for Cancer Research Bethesda USA Innovascreen Inc. New Glasgow Canada Innovascreen Inc. New Glasgow Canada Department of.Oncology University of Alberta Edmonton Canada Tissue Array Research Laboratory of Pathology Center for Cancer Research National Cancer Institute Bethesda USA Tissue Array Research Laboratory of Pathology Center for Cancer Research National Cancer Institute Bethesda USA 4Department of Pathology University of Washington Seattle USA Tumor Growth f.ctor Section Laboratory of Cancer Prevention Center for Cancer Research National Cancer Institute Frederick USA

The gut hormone apelin is a major therapeutic f.cus f.r several diseases involving inf.ammation and aberrant cell growth. We investigated whether apelin-36 contained alternative bioactive peptides associated with normal physiology or disease. Amino acid sequence analysis of.apelin-36 identif.ed an amidation motif.consistent with the f.rmation of.a secondary bioactive peptide (SCNH2). SCNH2 is proven to be mitogenic and chemotactic in normal/malignant cells and augments angiogenesis via a PTX-resistant/CT-X-sensitive G protein-coupled receptor (GPCR). Notably, SCNH2 is substantially more potent and sensitive than apelin-13 and vascular endothelial growth f.ctor-A. Endogenous SCNH2 is highly expressed in human tumors and placenta and in mouse embryonic tissues. Our f.ndings demonstrate that SCNH2 is a new apelinergic member with critical pluripotent roles in angiogenesis related diseases and embryogenesis via a non-APJ GPCR.

关键词： Novel Apelinergic Member SCNH2 Angiogenesis Migration Embryogenesis

Non-physician endoscopists: A systematic review

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World Journal of.Gastroenterology 2015年第16期21卷 5056-5071页

作者： Maximilian Stephens Luke f.Hourigan Mark Appleyard George Ostapowicz Mark Schoeman Paul V Desmond Jane M Andrews Michael Bourke David hewitt David A Margolin Gerald J Holtmann Department of.Gastroenterology and Hepatology Princess Alexandra Hospital f.culty of.Medicine and Biomedical Sciences University of Queensland Department of.Gastroenterology and Hepatology RBWH Department of.Gastroenterology and Hepatology Gold Coast Hospital QLD 4215 Department of.Gastro-enterology and Hepatology Royal Adelaide Hospital and University of Adelaide St Vincent’s Hospital University of MelbourneMelbourne VIC 3010Australia Department of.Gastroenterology and Hepatology Westmead HospitalUniversity of Sydney School of.Medicine University of Queensland Department of.Gastroenterology Queensland Elizabeth II Jubilee HospitalCoopers PlainsBrisbane QLD 4108Australia Department of.Colon and Rectal Surgery Ochsner Clinic f.undation Ochsner Clinical SchoolUniversity of Queensland

AIM:To examine the available evidence on saf.ty, competency and cost-ef.ectiveness of.nursing staf. providing gastrointestinal(GI) endoscopy ***:The literature was searched f.r publications reporting nurse endoscopy using several databases and specif.c search *** were screened against eligibility criteria and f.r *** searches yielded 74 eligible and relevant articles; 26 of.these studies were primary research articles using original datasets relating to the ability of.nonphysician *** publications included a total of.28883 procedures perf.rmed by non-physician ***:The number of.publications in the f.eld of.non-specialist gastrointestinal endoscopy reached a peak between 1999 and 2001 and has decreased thereaf.er.17/26 studies related to f.exible sigmoidoscopies,5 to upper GI endoscopy and 6 to *** studies were f.om metropolitan centres with nurses working under strict supervision and guidance by specialist *** distribution of.publications showed the majority of.research was conducted in the United States(43%),the United Kingdom(39%)and the Netherlands(7%).Most studies conclude that af.er appropriate training nurseendoscopists saf.ly perf.rm ***,in relation to endoscopic competency,saf.ty or patient satisf.ction,all studies had major methodological *** were of.en not randomized(21/26studies)and not appropriately *** relation to cost-ef.iciency,nurse endoscopists were less costef.ective per procedure at year 1 when compared to services provided by physicians,due largely to the increased need f.r subsequent endoscopies,specialist f.llow-up and primary care ***:Contrary to general belief.,endoscopic services provided by nurse endoscopists are not more cost ef.ective compared to standard service models and evidence suggests the *** signif.cant shortcomings and biases limit the validity and

关键词： Nurse endoscopist Cost-benef.t Servicemodel Patient satisf.ction Outcome parameter

一个精密测量卫星位置用的f.l平像场施密特系统

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光学工程 1974年第1期 16-28页

作者： J.hewitt 姜文汉英国航空部皇家雷达机构

本文所讲述的相机是为获得最大的灵敏度和1弧秒的测量精度而设计的。光学系统是由一个630毫米直径的简单的非球面校正板和800毫米孔径的球面反射镜组成的施密特(Schmidt)型系统。此系统将来自离系统光轴10°范围以内的物体的全部光线反... 详细信息

本文所讲述的相机是为获得最大的灵敏度和1弧秒的测量精度而设计的。光学系统是由一个630毫米直径的简单的非球面校正板和800毫米孔径的球面反射镜组成的施密特(Schmidt)型系统。此系统将来自离系统光轴10°范围以内的物体的全部光线反射到成像圆内。反射镜用径向和轴向的配重系统平衡。在照相底板前方装有一个平像埸透镜。使用两个快门。一个膜片式快门,位于光学系统的孔径处,用于恒星曝光的定时。一个靠近焦面的转动扇形快门产生卫星光迹的定时间隔。这种间隔的时间可达0.1毫秒,精度为±0.1毫秒。定时系统是一个由1兆周的晶体管振荡器和与之相连接的电路所推动的石英钟。恒星校正曝光是在卫星通过相机视埸之前和之后进行的。本文还讲述了系统精度的试验和用于一个测地卫星的情况。

关键词：像场光学系统相机 f.l 基准标记曝光时间间隔数焦距视场卫星位置

对两个家庭两种罕见遗传性皮肤病(帕-列综合征和Ⅰ型眼皮肤白化病)的共同继承的遗传学研究

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世界核心医学期刊文摘（皮肤病学分册） 2005年第5期1卷 19-19页

作者： hewitt C. Hattab f.N. N.S. Thakker 牛新武 Unit of.Medical Genetics University of Manchester Manchester M13 OJH United Kingdom

The co-occurrence of.two rare recessive genetic conditions in apparently unre lated individuals or f.milies is extremely rare. Two geographically distant and apparently unrelated f.milies were identif.ed in which individuals were simultan eously af.ected by two rare recessive mendelian syndromes, Papillon-Lef.vre syn drome and type 1 oculocutaneous albinism. The f.milies were tested f.r mutations in the causative genes, cathepsin C (CTSC) and tyrosinase (TYR), respectively, by direct sequencing. To assess the relationship of.the two f.milies, both f.mil ies were tested f.r polymorphisms at eight microsatellite markers spanning both CTSC and TYR loci. Independent mutations (c.318-1G →A and c.817G →.C/p.W272C) were identif.ed in CTSC and TYR, respectively, that were shared by the af.ected individuals in both f.milies. The two af.ected genes lie close together on chro mosome bands 11q14.2-14.3, and studies with linked genetic markers suggested th at the f.milies shared a small chromosomal segment carrying both mutations that had been transmitted intact f.om a remote common ancestor. The co-occurrence of.the two rare diseases in multiple f.milies depends on their shared chromosomal location, but not on any shared pathogenic mechanism.

关键词：遗传性皮肤病眼皮肤白化病掌跖角化过度隐性遗传病酪氨酸酶染色体带突变检测组织蛋白酶多态现象序列分析法