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Methylation of DAPK and THBS1 genes in esophageal gastric-type columnar metaplasia

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World Journal of Gastroenterology 2016年第18期22卷 4567-4575页

作者： Roberto Herrera-Goepfert Luis f Onate-Ocana José Luis Mosqueda-Vargas Luis A Herrera Clementina Castro Julia Mendoza Rodrigo González-Barrios Department of Pathology Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Clinical Research Division Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Unidad de Investigacion Biomedica en Cancer Instituto Nacional de Cancerologia (INCan)-Instituto de Investigaciones Biomedicas (IIB) Universidad Nacional Autonoma de Mexico (UNAM) 14080 Mexico DF Mexico

AIM: To explore methylation of DAPK, THBS1, CDH-1, and p14 genes, and Helicobacter pylori(H. pylori) status in individuals harboring esophageal columnar ***: Distal esophageal mucosal samples obtained by endoscopy and histologically diagnosed as gastric-type(non-specialized) columnar metaplasia, were studied thoroughly. DNA was extracted from paraffin blocks, and methylation status of deathassociated protein kinase(DAPK), thrombospondin-1(THBS1), cadherin-1(CDH1), and p14 genes, was examined using a methyl-sensitive polymerase chain reaction(MS-PCR) and sodium bisulfite modification protocol. H. pylori cag A status was determined by ***: In total, 68 subjects(33 females and 35 males), with a mean age of 52 years, were included. H. pylori cag A positive was present in the esophageal gastric-type metaplastic mucosa of 18 individuals. DAPK, THSB1, CDH1, and p14 gene promoters were methylated by MS-PCR in 40(58.8%), 33(48.5%), 46(67.6%), and 23(33.8%) cases of the 68 esophageal samples. H. pyloristatus was associated with methylation of DAPK(P = 0.003) and THBS1(P = 0.019).CONCLUSION: DNA methylation occurs in cases of gastric-type(non-specialized) columnar metaplasia of the esophagus, and this modification is associated with H. pylori cag A positive infection.

关键词： DNA methylation Esophageal columnar metaplasia Thrombospondin-1 Death-associated protein kinase Helicobacter pylori cagA

Improving the Thermal Efficiency and Performance of Refrigeration Systems:Numerical-Experimental Analysis of Minimization of frost formation

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Energy Engineering 2022年第5期119卷 1771-1788页

作者： felipe Mercês Biglia Raquel da Cunha Ribeiro da Silva fátima deMoraes Lino Kamal Abdel Radi Ismail Thiago Antonini Alves federal University of Technology-Parana(UTfPR) CuritibaBrazil federal University of Technology-Parana(UTfPR) GuarapuavaBrazil University of Campinas(UNICAMP) CampinasBrazil federal University of Technology-Parana(UTfPR) Ponta GrossaBrazil

The frost growth on cold surfaces in evaporators is an undesirable phenomenon which becomes a problem for the thermal efficiency of the refrigeration systems because the ice layer acts as a thermal insulation,drastically reducing the rate of heat transfer in the *** accumulation implies an increase in energy demand and a decrease in the performance of various components involved in the refrigeration process,reducing its efficiency and making it necessary to periodically remove the frost,resulting in expenses for the defrost *** the present work,a numerical-experimental analysis was performed in order to understand the formation process of porous ice in flat plates with different surface treatments and *** understanding is of utmost importance to minimize the formation of porous ice on cold surfaces and improve equipment efficiency and *** this context,a low-cost experimental apparatus was developed,enabling an experimental analysis of the phenomenon under *** environmental conditions evaluated are the temperature of the cold surface,roomtemperature,humidity,and air *** material of the surfaces under study are aluminum,copper,and brass with different surface finishes,designated as smooth,grooved(hydrophilic),and varnished(hydrophobic).The numerical-experimental analysis demonstrates measurements and simulations of the thickness,surface temperature,and growth rate of the porous ice layer as a function of the elapsed *** numerical results were in good agreement with the experimental results,indicating that the varnished surface,with hydrophobic characteristics,presents greater difficulty in providing the ***,the results showed that application of a coating allowed a significant reduction on the frost formation process contributing to the improvement of thermal efficiency and performance of refrigeration systems.

关键词： frost layer growth frost thickness minimization of frost hydrophobic surface refrigeration systems

functional traits shape size-dependent growth and mortality rates of dry forest tree species

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Journal of Plant Ecology 2017年第6期10卷 895-906页

作者： Jamir A.Prado-Junior Ivan Schiavini Vagner S.Vale Diego Raymundo Sergio f.Lopes Lourens Poorter Biology Institute Federal University of UberlandiaUberlandiaBrazil forest Ecology and forest Management Group Wageningen UniversityPO Box 476700 AA WageningenThe Netherlands forestry Department State University of Goias-Ipameri CampusRoad GO-330 Km 24175780-000 IpameriBrazil Biological Sciences Institute Federal University of Juiz de Fora 36036-900Juiz de ForaBrazil Biology Department State University of ParaibaBaraunas street 58429-500Campina GrandeBrazil

Aims functional traits have emerged as an important tool to evaluate plant ***,the environmental conditions and ecological pressures that plants face change with their size,and the relationship between traits and plant performance should therefore be size-dependent,which has rarely been *** Here,we evaluated over a broad range of tree sizes the interspe-cific relationship between tree growth and mortality and eight func-tional stem,leaf and seed *** did so across 59 tree species in Brazilian dry forests and evaluated whether the relationships found for wet forest types in the literature also hold for dry forests,where water rather than light might limit tree *** findings We indeed found a strong size-dependent relationship between demographic rates and functional *** small sizes,when trees are in the shaded understory,species with functional trait values that enhance light capture or shade tolerance(*** maximum adult stature,taller heights,wider crowns,higher seed mass)have higher growth and/or lower mortality rates(MR).This relationship disappears at larger sizes when trees attain better light conditions in the *** adaptations play only a role at larger tree sizes;once trees are in the dry and exposed canopy,species with higher wood density(an indicator of cavitation resistance)have lower *** study shows that both drought and shade adaptations are important in this dry forest,and that the relationships between func-tional traits and plant performance changes with plant *** size should therefore explicitly be included as an axis of variation in functional analyses,to better understand the relationship between functional traits and demographic rates.

关键词： demographic rates leaf traits seed mass tree architecture wood density

玉米赤霉烯酮饲粮添加蒙脱石对断奶仔猪脾脏和外周血免疫指标的影响

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中国粮油学报 2013年第7期28卷 60-65页

作者：姜淑贞杨维仁杨在宾王淑静刘法孝 Chi f 山东农业大学动物科技学院泰安271018 Amlan International Chicago 60626

选择(28±1)日龄、平均体重为(8.84±0.21)kg的健康三元(斯格×长×大)杂交断奶仔猪(公母各半)18头,研究1 mg/kg玉米赤霉烯酮(zearalenone,ZEA)污染饲粮对断奶仔猪脾脏和外周血淋巴细胞增殖率和IL-2产量的影响,同时评价改性蒙脱石的脱... 详细信息

选择(28±1)日龄、平均体重为(8.84±0.21)kg的健康三元(斯格×长×大)杂交断奶仔猪(公母各半)18头,研究1 mg/kg玉米赤霉烯酮(zearalenone,ZEA)污染饲粮对断奶仔猪脾脏和外周血淋巴细胞增殖率和IL-2产量的影响,同时评价改性蒙脱石的脱毒效应。将试验仔猪按照体重随机分为3个处理(公母各半),仔猪采用试验笼单独饲养。试验处理为:Contr.=基础饲粮;ZEA+CZ0=基础饲粮+1 mg/kg ZEA;ZEA+CZ4=基础饲粮+1 mg/kg ZEA+4 g/kg改性蒙脱石。预饲期7 d,正式期22 d。结果表明:1)与对照组相比,饲粮添加1 mg/kg ZEA显著降低断奶仔猪脾脏相对重量、外周血和脾脏淋巴细胞增殖率以及IL-2产量(P<0.05)。2)1 mg/kg的ZEA处理饲粮添加4 g/kg改性蒙脱石能够显著改善ZEA诱导的脾脏和外周血淋巴细胞增值率以及IL-2的改变(P<0.05)。结果揭示,1 mg/kg的ZEA足以影响断奶仔猪脾脏的生长发育及其细胞免疫功能,添加4 g/kg改性蒙脱石具有显著的脱毒效应,以上结果对指导动物生产和人类健康具有重要的借鉴意义。

关键词：仔猪玉米赤霉烯酮改性蒙脱石淋巴细胞增殖率 IL-2

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驱动胎轮牵引性能的田间试验研究

农业工程学报 1995年第1期11卷 95-98页

作者：洪添胜 J.f.Billot J.f.Goupillon A.Marionneau 华南农业大学法国国家农业工程研究中心

为了解后轮沿前轮行驶的拖拉饥,在不同土壤条件下的牵引性能,建立其预测模型,通过单轮驱动试验装置试验测定表明,在粘壤土中,行驶在轮辙内的子午线驱动轮胎,其牵引性能优于行驶在轮辙外;而在砂土中却没有多大差别;此外该驱动轮的牵引力... 详细信息

为了解后轮沿前轮行驶的拖拉饥,在不同土壤条件下的牵引性能,建立其预测模型,通过单轮驱动试验装置试验测定表明,在粘壤土中,行驶在轮辙内的子午线驱动轮胎,其牵引性能优于行驶在轮辙外;而在砂土中却没有多大差别;此外该驱动轮的牵引力系数有随其前进速度增加而减少的趋势。

关键词：驱动轮牵引性能轮辙拖拉机

男性吸烟者体重对烟碱引起的生热作用和儿茶酚胺释放的影响(英文)

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生理学报 2002年第5期54卷 405-410页

作者： J.f.Walker C.J.Kane 贝拉明大学心肺科学研究室美国肯塔基州40205

本研究的目的是在中年男子中观察禁食情况下吸烟后烟碱对安静时能量消耗 (restingenergyexpendi ture ,REE)和血浆儿茶酚胺浓度的影响 ;并且在正常体重 (BMI≤ 2 5kg/m2 )和超重 (BMI >2 5kg/m2 )吸烟者之间比较吸烟引起的REE和血浆儿... 详细信息

本研究的目的是在中年男子中观察禁食情况下吸烟后烟碱对安静时能量消耗 (restingenergyexpendi ture ,REE)和血浆儿茶酚胺浓度的影响 ;并且在正常体重 (BMI≤ 2 5kg/m2 )和超重 (BMI >2 5kg/m2 )吸烟者之间比较吸烟引起的REE和血浆儿茶酚胺的急性反应是否有差别。对 32名禁食的男性吸烟者用间接测热法分别在吸烟前和吸 2支含 0 16mg烟碱 (低烟碱 )或 2支含 1 74mg烟碱 (高烟碱 )香烟 30min后测定REE ,同时测定血浆中烟碱和去甲肾上腺素浓度。正常体重组在吸低烟碱烟后和超重组不论在吸低烟碱烟或高烟碱烟后 ,REE和血浆儿茶酚胺均无明显改变。而在正常体重组中 ,吸高烟碱烟后血浆去甲肾上腺素浓度升高 ,同时REE增加7 2 % ;如果将血浆烟碱水平作为一个共变量进行分析 ,则吸烟后血浆去甲肾上腺素浓度和REE的改变也不明显 ,表明吸烟后的生热效应是因血浆烟碱浓度升高而引起的。体重对烟碱的生热效应能发生影响 ,在超重的吸烟者中烟碱的生热效应减弱。由此推测 ,正常体重的吸烟者在戒烟后 ,由于不再有吸烟引起的耗能生热。

关键词：男性吸烟者体重烟碱生热作用儿茶酚胺释放

Controllable synthesis of Na P zeolite and its application in calcium adsorption

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Science China Materials 2015年第8期58卷 621-633,593页

作者： Ibraheem O.Ali Said M.El-Sheikh Tarek M.Salama Mostafa f.Bakr Mohamed H.fodial Department of Chemistry Faculty of Science Al-Azhar University Nanostructured Materials Lab Advanced Materials Department Central Metallurgical R&D Institute (CMRDI)

NaP zeolite particles were prepared through a template-free hydrothermal condition at 100oC. Parameters like Na2O/Si O2 and Si O2/Al2O3 molar ratios, gel aging time and aging temperature were investigated for regulating the crystallization of the final product. The samples at different synthesis stages were characterized with N2 adsorption at-196oC, field emission scanning electron microscopy(fE-SEM), temperature programmed desorption of ammonia adsorption, X-ray diffraction, thermogravimetric and differential scanning calorimetry analysis and fourier transform infrared spectroscopy. The experimental results evidenced that a high ordering crystallinity of Na P zeolite was obtained at Na2O/Si O2 and Si O2/Al2O3 molar ratios of 1.10 and 1.40, respectively, and a temperature of 100°C for 4 days of aging. fE-SEM image exhibited polycrystalline aggregates of Na P zeolite with crystallite sizes ranging up to 5.04 μm with cactus/cabbage like structures. The quantitative analysis of the total number of acid sites was found to increase as Na2 O increases. The Na P zeolite sample with a Na2O/Si O2 molar ratio of 1.13 exhibited a large fraction of the acid sites on its external surface, contrary to that synthesized with a relevant ratio of 1.10. The optimized Na P zeolite could be successfully bestowed with excellent sorption properties of Ca(II) in aqueous solution. The kinetic parameters for Ca(II) adsorption were thoroughly investigated.

关键词：分子筛钙离子合成泡沸石凝血因子Ⅳ NaP Al 摩尔比 Si

Discrimination and stratification tests of cardiovascular disease risk assessment models against ultrasound detection of carotid plaques in type 2 diabetics

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Health 2013年第7期5卷 1-10页

作者： Lawrence W. C. Chan Yu Sun Iris f. f. Benzie Department of Health Technology and Informatics Hong Kong Polytechnic University Hung Hom China

Atherosclerosis is the early stage of arterial disease, and underlies development of cardiovascular disease (CVD) and stroke. Although sophisticated models for assessing CVD and stroke risk have been derived based on large-scale prospective studies, their abilities in detecting the presence or absence of atherosclerotic plaque have not been investigated. This study aimed to evaluate and compare discriminatory and risk stratifying abilities of 13 CVD risk assessment models against the ultrasound detection of carotid plaques in type 2 diabetes mellitus (T2DM) patients. forty-nine T2DM subjects were recruited with informed consent, and major anthropomorphic and biomarker data for these models were collected. The model risk scores were evaluated against the carotid plaques detected by Doppler ultrasound. Only the fHS-Lpts-CHD-10Y model, which is a variant of the framingham model, revealed an area under the receiver operating curve (AUROC) that was significantly different from a random scoring approach (AUROC: 0.681, p was able to stratify the risk levels of carotid plaque presence (Chi-Square statistic: 5.99,

关键词： Atherosclerosis Cardiovascular Disease Doppler Ultrasound Risk Assessment

H_2O_2在具有纳米结构的Rh微电极上的电催化氧化(英文)

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电化学 2012年第5期18卷 457-471页

作者： Philip N.Bartlett Thomas f.Esterle 南安普顿大学化学系 Department d'Enginyeria Quimica Universitat Rovira i Virgili

在含有C12EO8(Octaethyleneglycol Monododecyl Ether)的H1溶致液晶相中Pt微电极上电沉积Rh介孔膜.该电极在中性、低浓度(CH2O2<10 mmol.L-1)条件下,对H2O2有较好的氧化还原响应及稳定性.由于电流磁滞效应,H2O2在Rh介孔膜微电极上的氧... 详细信息

在含有C12EO8(Octaethyleneglycol Monododecyl Ether)的H1溶致液晶相中Pt微电极上电沉积Rh介孔膜.该电极在中性、低浓度(CH2O2<10 mmol.L-1)条件下,对H2O2有较好的氧化还原响应及稳定性.由于电流磁滞效应,H2O2在Rh介孔膜微电极上的氧化与电位相关,且遵循与Rh(OH)3有关的CEE(Chemical reaction step by two sequential electrochemical steps)反应机制.H2O2浓度较大时,由于孔电极表面其结合点位趋于饱和或孔内溶液酸化的反应限制,电流呈现一平台.Rh介孔膜厚度小于200 nm的电极,H2O2浓度校正曲线符合膜孔反应一维扩散模型.

关键词： H2O2 Rh 微电极纳米孔溶致液晶模板电沉积