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Difficult biliary cannulation: Historical perspective, practical updates, and guide for the endoscopist

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World Journal of Gastrointestinal Endoscopy 2019年第1期11卷 5-20页

作者： Rani Berry james Y han james H Tabibian Department of Internal Medicine Ronald Reagan UCLA Medical Center Department of Internal Medicine University of CaliforniaIrvine Geffen School of Medicine at UCLA Olive View-UCLA Medical Center

Despite improvements in endoscopic technologies and accessories, development of advanced endoscopy fellowship programs, and advances in ancillary imaging techniques, biliary cannulation in endoscopic retrograde cholangiopancreatography(ERCP) can still be unsuccessful in up to 20% of patients, even in referral centers. Once cannulation has been deemed to be difficult, the risk of post-ERCP pancreatitis and technical failure inherently increases. A number of factors, including endoscopist experience and patient anatomy, have been associated with difficult biliary cannulation, but predicting a case of difficult cannulation a priori is often not possible. Numerous techniques such as pancreatic guidewire and stenting, early pre-cut, and rendezvous may be employed when standard approaches fail. Data regarding the rate of success and adverse events of these techniques have been variable, though most studies suggest that pancreatic duct stenting generally reduces the rate of post-ERCP pancreatitis in instances of difficult biliary cannulation. Here we provide a review on difficult biliary cannulation and discuss how the choice of which techniques to employ and how to best employ them should be individualized and take into account the skill of the endoscopist, the disorder being treated, the anatomy of the patient, and the available biomedical literature.

关键词： Selective biliary cannulation Post-endoscopic retrograde cholangiopancreatography pancreatitis Periampullary diverticulum Precut technique Endoscopic ultrasound Rendezvous endoscopic retrograde cholangiopancreatography

Unveiling the distinctive traits of functional rye centromeres:minisatellites,retrotransposons,and R-loop formation

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Science China(Life Sciences) 2024年第9期67卷 1989-2002页

作者： Chang Liu Shulan Fu Congyang Yi Yang Liu Yuhong Huang Xianrui Guo Kaibiao Zhang Qian Liu james A.Birchler Fangpu han State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Plant Genetics and Breeding Sichuan Agricultural UniversityChengdu 611130China Division of Biological Science University of MissouriColumbia 65211-7400USA

Centromeres play a vital role in cellular division by facilitating kinetochore assembly and spindle *** their conserved functionality,centromeric DNA sequences exhibit rapid evolution,presenting diverse sizes and compositions across *** functional significance of rye centromeric DNA sequences,particularly in centromere identity,remains *** this study,we comprehensively characterized the sequence composition and organization of rye *** findings revealed that these centromeres are primarily composed of long terminal repeat retrotransposons(LTR-RTs)and interspersed *** systematically classified LTR-RTs into five categories,highlighting the prevalence of younger CRS1,CRS2,and CRS3 of CRSs(centromeric retrotransposons of Secale cereale)were primarily located in the core centromeres and exhibited a higher association with CENH3 *** minisatellites,mainly derived from retrotransposons,along with CRSs,played a pivotal role in establishing functional centromeres in ***,we observed the formation of R-loops at specific regions of CRS1,CRS2,and CRS3,with both rye pericentromeres and centromeres exhibiting enrichment in ***,these R-loops selectively formed at binding regions of the CENH3 nucleosome in rye centromeres,suggesting a potential role in mediating the precise loading of CENH3 to centromeres and contributing to centromere *** work provides insights into the DNA sequence composition,distribution,and potential function of R-loops in rye *** knowledge contributes valuable information to understanding the genetics and epigenetics of rye centromeres,offering implications for the development of synthetic centromeres in future plant modifications and beyond.

关键词： centromere LTR-RTs minisatellite rye R-loop

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简化Markov模型的可靠性分析(英文)

电路与系统学报 2004年第1期9卷 122-125页

作者：蒋乐天徐国治应忍冬张昊 han james J 上海交通大学电子工程系上海200030 Motorola全球软件中心

Markov模型是电子产品系统可靠性分析中最常使用的方法。但在应用Markov模型的时候一个主要的问题是它的巨大的状态数,使得它对复杂系统的建模和分析变得非常困难。本文提出了一种新的简化Markov模型的方法来简化对系统可靠性的分析。... 详细信息

Markov模型是电子产品系统可靠性分析中最常使用的方法。但在应用Markov模型的时候一个主要的问题是它的巨大的状态数,使得它对复杂系统的建模和分析变得非常困难。本文提出了一种新的简化Markov模型的方法来简化对系统可靠性的分析。并且对该简化方法的误差界限进行了讨论。数值仿真结果表明了该方法的有效性。

关键词： Markov模型简化方法误差界限

Artificial intelligence-enabled studies on organoid and organoid extracellular vesicles

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Biomaterials Translational 2024年第2期5卷 93-94页

作者： han Liu james T.Triffitt Zhidao Xia Jiacan Su Institute of Translational Medicine Shanghai UniversityShanghaiChina Department of Orthopedics Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina National Center for Translational Medicine(Shanghai)SHU Branch Shanghai UniversityShanghaiChina Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal SciencesOxford UniversityOxfordUK Centre for Nanohealth Swansea University Medical SchoolSwansea UniversitySwanseaUK

In the field of medical research,studies of organoids and organoid extracellular vesicles(OEVs)are leading a revolutionary change.1 Organoids are simplified,miniaturised versions of organs that simulate the microenvironment of human tissues,and have broad applications in disease modelling,drug development,and regenerative *** vesicles(EVs)are tiny vesicles secreted from various cells,containing proteins,lipids,RNA,and other biomolecules.

关键词： simplified vesicles organs

Centromere Epigenetics in Plants

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Journal of Genetics and Genomics 2013年第5期40卷 201-204页

作者： james A.Birchler Fangpu han Division of Biological Science University of Missouri-Columbia311 Tucker HallColumbia MO 65211-7400USA State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences

The centromere is an essential chromosome site at which the kinetochore forms and loads proteins needed for faithful segregation during the cell cycle and meiosis（Houben et al., 1999;Cleveland et al.,2003;Ma et al.,2007;Birchler and han,2009）.Centromere specific sequences such as tandem repeats or transposable elements evolve quickly both within and between the species but have conserved kinetochore proteins（Henikoff and Furuyama,2010）.

关键词： Centromere Epigenetics in Plants DNA 飞飞 FISH

Development of single-cell-level microfluidic tech no logy for long-term growth visualization of living cultures of Mycobacterium smegmatis

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Microsystems & Nanoengineering 2021年第3期7卷 63-72页

作者： han Wang Gloria M.Conover Song-I han james C.Sacchettini Arum han Department of Biomedical Engineering School of MedicineTsinghua University100084 BeijingChina Department of Biochemistry and Biophysics Texas A&M UniversityCollege StationTX 77843USA Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Biomedical Engineering Texas A&M UniversityCollege StationTX 77843USA Department of Medical Education Health Sciences CenterTexas A&M UniversityBryanTX 77807USA

Analysis of growth and death kinetics at single-cell resolution is a key step in understanding the complexity of the nonreplicating growth phenotype of the bacterial pathogen Mycobacterium ***,we developed a single-cell-resolution microfluidic mycobacterial culture device that allows time-lapse microscopy-based Iong-term phenotypic visualization of the live replication dynamics of *** technology was successfully applied to monitor the real-time growth dynamics of the fast-growing model strain Mycobacterium smegmatis(***)while subjected to drug treatment regimens during continuous culture for 48 h inside the microfluidic device.A clear morphological change leading to significant swelling at the poles of the bacterial membrane was observed during drug *** addition,a small subpopulation of cells surviving treatment by frontline antibiotics was observed to recover and achieve robust replicative growth once regular culture media was provided,suggesting the possibility of identifying and isolating nonreplicative *** device is a simple,easy-to-use,and low-cost solution for studying the single-cell phenotype and growth dynamics of mycobacteria,especially during drug treatment.

关键词： fluid culture treatment Mycobacterium

Dicentric Chromosome Formation and Epigenetics of Centromere Formation in Plants

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Journal of Genetics and Genomics 2012年第3期39卷 125-130页

作者： Shulan Fu Zhi Gao james Birchler Fangpu han State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of ScienceBeijing 100101China Division of Biological Sciences 311 Tucker HallUniversity of MissouriColumbiaMissouri 65211USA

Plant centromeres are generally composed of tandem arrays of simple repeats that form a complex chromosome locus where the kinetochore forms and microtubules attach during mitosis and meiosis. Each chromosome has one centromere region, which is essential for accurate division of the genetic material. Recently, chromosomes containing two centromere regions （called dicentric chromosomes） have been found in maize and wheat. Interestingly, some dicentric chromosomes are stable because only one centromere is active and the other one is inactivated. Because such arrays maintain their typical structure for both active and inactive centromeres, the specification of centromere activity has an epigenetic component independent of the DNA sequence. Under some circumstances, the inactive centromeres may recover centromere function, which is called centromere reactivation. Recent studies have highlighted the important changes, such as DNA methylation and histone modification, that occur during centromere inactivation and reactivation.

关键词： Centromere Inactivation Epigenetics Wheat Maize

Generating high-resolution climate maps from sparse and irregular observations using a novel hybrid RBF network

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Big Earth Data 2023年第4期7卷 1120-1145页

作者： Yue han Zhihua Zhang M.james C.Crabbe Climate Modeling Laboratory School of MathematicsShandong UniversityJinanChina MOE Key Laboratory of Environmental Change and Natural Disaster Beijing Normal UniversityBeijingChina Wolfson College Oxford UniversityOxfordUK

Sparse and irregular climate observations in many developing countries are not enough to satisfy the need of assessing climate change risks and planning suitable mitigation *** wideused statistical downscaling model(SDSM)software tools use multi-linear regression to extract linear relations between largescale and local climate variables and then produce high-resolution climate maps from sparse climate *** latest machine learning techniques(***,SRGAN)can extract nonlinear links,but they are only suitable for downscaling low-resolution grid data and cannot utilize the link to other climate variables to improve the downscaling *** this study,we proposed a novel hybrid RBF(Radial Basis Function)network by embedding several RBF networks into new RBF *** model can well incorporate climate and topographical variables with different resolutions and extract their nonlinear relations for spatial *** test the performance of our model,we generated high-resolution precipitation,air temperature and humidity maps from 34 meteorological stations in *** terms of three statistical indicators,the accuracy of high-resolution climate maps generated by our hybrid RBF network clearly outperformed those using a multi-linear regression(MLR),Kriging interpolation or a pure RBF network.

关键词： Hybrid RBF network climate map sparse observed climate data high resolution

A laterally sensitive colloidal probe for accurately measuring nanoscale adhesion of textured surfaces

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Nano Research 2019年第2期12卷 389-396页

作者： Soren Zimmermann Waldemar Klauser james Mead Shiliang Wang han Huang Sergej Fatikow Department of Computing Science University of Oldenburg Oldenburg D-26129 Germany School of Mechanical and Mining Engineering The University of Queensland Brisbane 4072 Australia School of Physics and Electronics Central South University Changsha 410083 China

Adhesiion assessment of nanoscale contacts is a critical capability for the development of future nanoelectromechanical systems and nanobiotechnology devices. However, experimental approaches to investigate interactions on micro- and nanostructured surfaces have predominantly been restricted to capturing adhesion force in the normal direction. This provides limited information about the multidimensional nature of surface texture and related interaction mechanisms. Here the design, fabrication, and application of a unique atomic force microscope probe is presented that consists of a focused ion beam-milled cantilever decorated with a colloidal particle. The probe is specifically developed for characterizing textured surfaces with lateral force feedback. Pull-off tests that map the adhesive interaction in microscale cavities are performed to exami ne the capability of the probe. Normal and lateral adhesive forces duri ng nano scale contact are accurately obtai ned and the adhesi on en ergy of the con tact interface is thus determi ned. An in-depth un dersta nding of the effects of surface texture and the correlati on of adhesi on and fricti on is dem on strated. The proposed methodology en ables dedicated in vestigatio ns of in terfacial in teracti on on various norvplanar surfaces. It can be used for un dersta nding the complex in terplay of adhesi on, con tact, and fricti on forces at nano scale, which may facilitate significant advances in challenging research areas such as fibrillar adhesion.

关键词： nanoscale adhesion friction atomic force microscope colloidal probe lateral sensitivity