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Effectiveness of serological markers of gastric mucosal atrophy in the gastric precancer screening and in cancer prevention

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World Journal of Gastrointestinal Endoscopy 2024年第8期16卷 462-471页

作者： Sergey M Kotelevets Sergey A Chekh Sergey z Chukov Department of Therapy North Caucasus State AcademyCherkessk 369000Karachay-Cherkess RepublicRussia Department of Mathematics North Caucasus State AcademyCherkessk 369000Karachay-Cherkess RepublicRussia Department of Pathological Anatomy Stavropol State Medical UniversityStavropol 355017Russia

BACKGROUND New markers are needed to improve the effectiveness of serological screening for atrophic *** To develop a cost-effective method for serological screening of atrophic gastritis with a high level of *** Of the 169 patients with atrophic gastritis,selected by the visual endoscopic Kimura-Takemoto method,165 showed histological mucosal atrophy using the updated Kimura-Takemoto *** 169 patients were examined for postprandial levels of gastrin-17(G17)and pepsinogen-1(PG1)using Gastro-Panel®(Biohit Plc,Helsinki,Finland).RESUlTS We used the histological standard of five biopsies of the gastric mucosa,in accordance with the Kimura-Takemoto classification system to assess the sensitivity of G17 in detecting gastric mucosal *** also compared the morphofunctional relationships between the detected histological degree of gastric mucosal atrophy and the serological levels of G17 and PG1,as the markers of atrophic *** sensitivity of postprandial G17 was 62.2%for serological levels of G17(range:0-4.pmol/l)and 100%for serological G17(range:0-10 pmol/l)for the detection of monofocal severe atrophic *** strong correlation was found between the levels of PG1 and degree of histological atrophy determined by the Kimura-Takemoto classification system to identify the severity of mucosal atrophy of the gastric *** the presented clinical case of a 63-year-old man with multifocal atrophic gastritis,there is a pronounced positive long-term dynamics of the serological marker of atrophy-postprandial G17,after five months of rennet replacement *** Serological screening of multifocal atrophic gastritis by assessment of postprandial G17 is a cost-effective method with high *** G17 is an earlier marker of regression of atrophic gastritis than a morphological examination of a gastric biopsy in accordance with the Sydney ***,postprandial G17 is recommended for dynamic monitorin

关键词： Updated Sydney system Kimura-Takemoto classification Prevention Gastric cancer Atrophic gastritis Gastrin-17 Pepsonogen-1

Effect of Solid Retention and Hydraulic Retention Times on Membrane Fouling in Membrane Bioreactor

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Journal of Environmental Science and Engineering 2010年第8期4卷 1-6页

作者： D. luintel z.l. Xu Membrane Science and Engineering R＆D lab Chemical Engineering Research Center East China University of Science andTechnology （ECUST） Shanghai 200237 China State Key laboratory of Chemical Engineering ECUST Shanghai 20023 7 China

In this bench scale submerged membrane bioreactor, effect of solid retention time and hydraulic retention time on membrane fouling propensity has been studied. This experiment is carried out at different solid retention time of 5, 10, 30, 70 and 98 days; and fouling behavior of membrane bioreactor is investigated. Average effluent quality is found to be 88.14.-94.38%. The experiment with different hydraulic retention is carried for 3 to 4.days and fouling behavior has been investigated. The effluent quality at different hydraulic retention time of 1, 2, 3, 5, 10 and 24.hours has been investigated. This paper aims to search optimal values of solid and hydraulic retention times at which lower fouling and higher organic removal efficiency can be obtained. This study has been mainly focused on operating parameters rather than microbial structure, effect and analysis of activated sludge to membrane fouling.

关键词： Membrane bioreactor membrane fouling solid retention time hydraulic retention time. wastewater treatment.

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氟化钙样物质的合成和检测的体外研究

中华口腔医学杂志 1995年第4期30卷 222-224页

作者：郑睿 Ra.,z.l. 北京医科大学口腔医学院材料研究室

牙釉质经氟化物处理后，表面生成“氟化钙样”的物质（“ＣａＦ＿２－ｌｉｋｅ”ｍａｔｅｒｉａｌｓ）。这种物质为量极少，且采集技术也有困难，故很难利用其作为防龋机理研究的样本。为获取代替牙面的氟化钙样物质，本研究采用化学合... 详细信息

牙釉质经氟化物处理后，表面生成“氟化钙样”的物质（“ＣａＦ＿２－ｌｉｋｅ”ｍａｔｅｒｉａｌｓ）。这种物质为量极少，且采集技术也有困难，故很难利用其作为防龋机理研究的样本。为获取代替牙面的氟化钙样物质，本研究采用化学合成的方法，制备了不同磷含量的氟化钙样物质，并分析、测定了这种物质在醋酸钾缓冲液中的溶解性能。对氟化钙样物质中磷与溶解性能的关系，作了定量的分析，并在其成分、溶解性、晶形结构等方面与纯氟化钙进行了比较。结果表明，用化学方法合成的氟化钙样物质，可以反应对牙面上氟化钙样物质的研究。本研究还验证了磷能使氟化钙样物质的结晶形态从立方晶形转变为微小的球滴状，溶解性随着磷含量的增加而加大。该实验是对氟防龋机理研究的一种方法。

关键词：氟化钙类龋齿磷牙釉质

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黄河下游叶蜡正构烷烃的物源指示意义

中国科学：地球科学 2024年第6期54卷 2031-2049页

作者：张亮刘金召姜崇张飞安芷生西安交通大学人居环境与建筑工程学院西安710054 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 陕西黄土高原地球关键带国家野外科学观测研究站西安710061

黄河作为输沙量和有机碳输送通量最大的河流之一,在区域生物地球化学及全球碳循环过程中发挥了至关重要的作用.目前,关于黄河总颗粒有机碳的通量、组成、来源及其季节变化已开展了大量研究,但针对不同时空尺度上分子生物标志物的研究仍... 详细信息

黄河作为输沙量和有机碳输送通量最大的河流之一,在区域生物地球化学及全球碳循环过程中发挥了至关重要的作用.目前,关于黄河总颗粒有机碳的通量、组成、来源及其季节变化已开展了大量研究,但针对不同时空尺度上分子生物标志物的研究仍然较少.本文重点研究了黄河下游不同季节(汛期、非汛期),不同类型载体中叶蜡正构烷烃的分子组成及氢同位素比值.结果表明:岸边表土中叶蜡正构烷烃的分子指标反映了其上覆植被的输入;汛期悬浮物的正构烷烃分子指标体现出黄土高原不同地质时期土壤的混合特征,而受水动力条件影响,非汛期悬浮物表现出相应的季节性差异;另外,考虑气候因素影响,利用正构烷烃氢同位素对汛期悬浮物中单子叶植物的输入进行了半定量化估算.本研究一定程度上为黄河有机质的物源研究中叶蜡指标的应用提供了新的见解.

关键词：分子组成氢同位素叶蜡正构烷烃悬浮物黄河下游

青藏高原及其周边古近纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1308-1342页

作者：刘佳宋艾丁林苏涛周浙昆中国科学院西双版纳热带植物园热带森林生态学重点实验室勐腊666303 中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 云南大学古生物研究院昆明650500 中国科学院青藏高原研究所地球系统科学与资源环境重点实验室北京100101

古近纪是陆地和海洋生态系统劫后复苏并逐渐接近其现代面貌的关键时期.在青藏高原及其周边区域,古近纪也是青藏高原-喜马拉雅造山带构造活动、亚洲气候重组、生物多样性演化的重要时期.限于研究条件、认识程度等的制约,青藏高原及其周... 详细信息

古近纪是陆地和海洋生态系统劫后复苏并逐渐接近其现代面貌的关键时期.在青藏高原及其周边区域,古近纪也是青藏高原-喜马拉雅造山带构造活动、亚洲气候重组、生物多样性演化的重要时期.限于研究条件、认识程度等的制约,青藏高原及其周边地区在地层划分方面还存在诸多争议.近年来,该区域开展了大量的沉积岩石学、磁性地层学、同位素年代学等工作,发现和报道了大量各种门类的化石,更系统地深化了生物地层学研究,为梳理青藏高原及其周边古近纪综合地层、生物群和古地理演化打下了坚实的基础.本文基于国际古近系划分和对比标准,以岩石地层和生物地层为基础,综合近年来同位素年代学、磁性地层学和地球化学等研究工作,在前人工作基础上梳理青藏高原及其周边不同构造单元的地层划分与对比框架.第二次青藏高原综合科学考察开展以来,古近纪植物群相关研究逐渐丰富.依据这些植物群最新的年代结果,本文讨论了灭绝类群和新出现类群的生物地层意义.对“桉属”、棕榈科等化石类群的新认识将古近纪青藏地区植物区系与冈瓦纳大陆的大洋洲、南美洲生物区系建立联系.雅鲁藏布江缝合带两侧植物群重要类群的演化历史也指示印度板块和欧亚大陆的碰撞时间在约65~54.a.植物群的古高程重建结果表明,横断山区在早渐新世之前就已经形成现今的地貌格局;古近纪青藏地区主要缝合带附近的温暖湿润低地是动植物类群交流的主要通道;古近纪低矮的喜马拉雅山脉不能对南来的印度洋水汽形成有效的阻隔作用.

关键词：青藏高原化石生物地层古环境古地理古近纪

SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko l.V.Kalinovskaya A.A.Kampf R.R.Sadykov V.l.Yermolchyk Bogoliubov laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the z boson resonance and at 24. GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Influence of Angiotensin II on 4.;₁-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells

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Journal of Biosciences and Medicines 2024年第4期12卷 123-134页

作者： Itz.l. Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido Santiago C. Sigrist-Flores Juan Javier lópez-Guerrero Enrique Hong Rafael Villalobos-Molina Unidad de Biomedicina Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico Carrera de Enfermerí a Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico Departamento de Farmacobiologí a Centro de Investigaci&#243n and de Estudios Avanzados-IPN Ciudad de M&#233xico M&#233xico Carrera de Mé dico Cirujano Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico

Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT1 and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α1-adrenergic receptors (α1-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24.h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10−5 M), and in some experiments, 5-Methylurapidil (α1A-AR antagonist), AH11110A (α1B-AR antagonist), or BMY-7378 (α1D-AR antagonist), were used to identify the α1-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α1D-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α1-ARs proteins were evaluated. α1D-AR increased at 30 and 60 min post Ang II exposure, the α1A-AR diminished from 1 to 4.h, while α1B-AR remained unchanged over 24.h of Ang II exposure. Ang II induced an increase of α1D-AR at short times, and BMY-7378 protected α1D-AR from desensitization.

关键词： Angiotensin II α1D-AR α1-AR Expression Rat aorta Smooth Muscle Cells

Phanerozoic co-evolution of O2-CO2 and ocean habitability

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National Science Review 2024年第6期11卷 18-21页

作者： zunli lu Rosalind E.M.Rickaby Jonathan l.Payne Ashley N.Prow Department of Earth & Environmental Sciences Syracuse University Department of Earth Sciences University of Oxford Department of Earth and Planetary Sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of Earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCENTRATING MECHANISM OXYGEN EVOlUTION ANOXIA

Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America

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Forest Ecosystems 2024年第5期11卷 728-742页

作者： zhihui Wang Philip A.Townsend Eric l.Kruger Anna K.Schweiger Guangdong Provincial Key laboratory of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Department of Forest and Wildlife Ecology University of Wisconsin-Madison1630 Linden DriveMadisonWI53706USA Department of land Resources and Environmental Sciences Montana State University334 Leon Johnson HallBozemanMT59717USA

Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental ***,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade *** presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 4.4.individuals of 110 plant species from 19 sites across eastern North *** investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait ***,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific *** between sun and shade leaf traits,and trait-environment relationships were overall consistent across *** main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural *** and canopy position collectively explained most of the foliar trait *** study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem *** findings have implications for efficient field sampling,and trait mapping with remote sensing.

关键词： Foliar traits leaf trait variation Trait-environment covariation Shade leaves NEON leaf spectroscopy