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Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

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Asian journal of Andrology 2015年第4期17卷 633-639页

作者： robert j Aitken Mark A Baker Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter explores the possibility that capacitation and apoptosis are linked processes joined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model capacitation is initiated in spematozoa following their release into the female reproductive tract as a consequence of intracellular ROS generation, which stimulates intracellular cAMP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterols prior to their removal from the sperm surface by albumin. The continued generation of ROS by capacitating populations of spermatozoa eventually overwhelms the limited capacity of these cells to protect themselves from oxidative stress. As a result the over-capacitation of spermatozoa leads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial RO$ generation, lipid peroxidation, motility loss, caspase activation and phosphatidylserine externalization. The latter may be particularly important in instructing phagocytic leukocytes that the removal of senescent, moribund spermatozoa should be a silent process unaccompanied by the generation of proinflammatory cytokines. These observations reveal the central role played by redox chemistry in defining the life and death of spermatozoa. A knowledge of these mechanisms may help us to engineer novel solutions to both support and preserve the functionality of these highly specialized cells.

关键词： apoptosis reactive oxygen species sperm capacitation

Choledocholithiasis: Evolving standards for diagnosis and management

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World journal of Gastroenterology 2006年第20期12卷 3162-3167页

作者： Marilee L Freitas robert L Bell Andrew j Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3 ANew HavenCT 06510United States

Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct （CBD） stones. CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans （CT）, and magnetic resonance cholangiopancreatography （MRCP）. Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones. The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability, of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is olden dictated by the clinical situation.

关键词： Choledocholithiasis Laparoscopy Diagnosis Treatment Cholangiogram

Evolution of surgical skills training

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World journal of Gastroenterology 2006年第20期12卷 3219-3224页

作者： Kurt E roberts robert L Bell Andrew j Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3ANew HavenCT 06510United Staets

Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education＇s （ACGME） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.

关键词： Surgery Training Certification Skills Simulation Curriculum

Crop Epigenomics： Identifying, Unlocking, and Harnessing Cryptic Variation in Crop Genomes

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Molecular Plant 2015年第6期8卷 860-870页

作者： Lexiang ji Drexel A. Neumann robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA Institute of Bioinformatics University of Georgia Athens GA 30602 USA These authors contributed equally to this article.

DNA methylation is a key chromatin modification in plant genomes that is meiotically and mitotically her- itable, and at times is associated with gene expression and morphological variation. Benefiting from the increased availability of high-quality reference genome assemblies and methods to profile single-base res- olution DNA methylation states, DNA methylomes for many crop species are available. These efforts are making it possible to begin answering crucial questions, including understanding the role of DNA methyl- ation in developmental processes, its role in crop species evolution, and whether DNA methylation is dynamically altered and heritable in response to changes in the environment. These genome-wide maps provide evidence for the existence of silent epialleles in plant genomes which, once identified, can be tar- geted for reactivation leading to phenotypic variation.

关键词： epigenomics DNA methylation whole-genome bisulfite sequencing (WGBS) crops comparativegenomics

Controversies in the treatment of gastroesophageal reflux and achalasia

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World journal of Gastroenterology 2006年第20期12卷 3155-3161页

作者： Kurt E roberts Andrew j Duffy robert L Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3 ANew HavenCT 06510United States

The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GERD evolves around laparoscopic antireflux surgery （LAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GERD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GERD. A new and promising alternative in the treatment of GERD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. Laparoscopic surgery is discussed not only as a very effective treatment for GERD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as LAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concer

关键词： Gastroesophageal reflux disease Nissen Toupet Fundoplication Achalasia Heller myotomy

Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo R G Barrocas William M Landing robert j M Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

Ethnic and Religious Violence in South China： The Hakka-Tiandihui Uprising of 1802

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Frontiers of History in China 2016年第4期11卷 532-562页

作者： robert j. Antony Canton's Thirteen Hongs Research Center Guangzhou University Guangzhou 510006 China

In 1802 the second major Tiandihui （Heaven and Earth Society） uprising erupted in the mountains of Huizhou prefecture near Canton. Before it was suppressed over a year later, the disturbances came to involve several tens of thousands of people and nearly a quarter of Guangdong province. This study, which is based on extant historical sources and fieldwork, takes an interdisciplinary approach, combining the methodologies of history, anthropology, and folklore. The areas where the uprising occurred were predominantly Hakka, an ethnic Chinese minority who came into conflict with the earlier settlers, known as the Punti. As violence escalated, both sides organized their own paramilitary units： Hakka formed Tiandihui groups and Punti formed Ox Head Societies. Significantly too, the Tiandihui groups in Huizhou belonged to a much wider network of secret society and sectarian organizations that spread across the Hakka heartland on the jiangxi, Fujian, and Guangdong border. This article addresses key issues concerning the social, political, and religious contexts and motivations of this Hakka-led uprising.

关键词： Hakka Punti Tiandihui ethnic feuds violence Buddhist lay sects Dachengjiao

Economic Growth and Convergence, Applied to China

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China & World Economy 2016年第5期24卷 5-19页

作者： robert j. Barro Warburg Professor of Economics Economics Department Harvard UniversityUSA

From the perspective of conditional convergence, China＇s GDP growth rate since 1990 has been surprisingly high. However, China cannot deviate forever from the global historical experience, and the per capita growth rate is likely to fall soon from around 8 percent per year to a range of 3-4 percent. China can be viewed as a middle-income convergence success story, grouped with Costa Rica, Indonesia, Peru, Thailand and Uruguay. Upper-income convergence successes （toward which China is likely heading） include Chile, Hong Kong, Ireland, Malaysia, Poland, Singapore, South Korea and Taiwan.

关键词： China convergence dispersion economic growth

Global Educational Research in Western Times:The Rise and Plight of Chinese Educational Research

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Frontiers of Education in China 2018年第2期13卷 163-192页

作者： robert j.TIERNEY Faculty of Education The University of British ColumbiaVancouverBC V6T 1Z2Canada Advanced Innovation Center for Future Education Beijing Normal UniversityBeijing 100875China

The paper offers a critical appraisal of the global knowledge developments in education using China’s contributions in a fashion similar to a case *** paper scrutinizes the complicity of Western educational research to euro-centric biases and discusses the pursuit of a global epistemological *** support this claim,the magnitude of the global knowledge economy,including country-by-country comparisons,is explored together with data pertaining to the success rate of submissions and *** data are used as the basis for arguments that the dominant research practices and developmental work serve Western interests,Western thought and a Western economy tied to standardization rather than eastern epistemological interests.

关键词： Chinese educational research globalization Westernization