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An improvement method for the detection of insitu telomerase activity : in situ telomerase activity labeling

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World Journal of Gastroenterology 1999年第6期5卷 535-537页

作者： feng DY Zheng H Fu cy Cheng RX Hunan Med Univ Dept Pathol Changsha 410078 Hunan Province Peoples R China

INTRODUCTIONTelomerase is a special reverse transcriptase which consists of a template RNA and protein, and uses the RNA template to catalyze the addition of telomeric DNA to chromosome ends[1-5]. The enzyme is active in adult male germ-line cells, embryonic cells and hemopoietic stems, but is undetectable in normal somatic cells except for proliferative cells of renewal tissue, e.g., activated lymphocytes, basal cells of the epidermis and intestinal crypt cells, whereas in almost all malignant tumor cells and immortal cell lines, telomerase activity has been measured. Thus, it is believed that activation of telomerase is closely associated with genesis and development of malignant tumors.

关键词： methodology telomerase in situ labeling polymerase chain reaction

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World Journal of Gastroenterology 2008年第28期14卷 4535-4539页

作者： Guo-Shuang feng Jun-Ling Ma Benjamin cy Wong Lian Zhang Wei-Dong Liu Kai-feng Pan Lin Shen Xiao-Dong Zhang Jie Li Harry HX Xia Ji-You Li Shiu Kum Lam Wei-Cheng You Department of Cancer Epidemiology Peking University School ofOncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Medicine University of Hong Kong Hong Kong China Department of Medical Oncology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Pathology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Healthy Bureau of Linqu County Weifang 262600 Shandong Province China

AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled ***: From 2004 to 2006, a total of 1024 Chinese patients (aged 35 to 64 years) with severe chronic atrophic gastritis, intestinal metaplasia or dysplasia were randomly assigned to receive 200 mg of celecoxib twice daily or placebo in Linqu County (Shandong Province, China), a high-risk area of gastric cancer. All gastroduodenal ulcer and cardiovascular events occurred were recorded and the patients were followed up for 1.5 years after treatment. At the end of the trial, a systematic interview survey about other adverse events was conducted. RESULTS: Gastroduodenal ulcer was detected in 19 of 463 (3.72%) patients who received celecoxib and 17 of 473 (3.31%) patients who received placebo, respectively (odds ratio = 1.13, 95% CI = 0.58-2.19). Cardiovascular (CV) events occurred in 4 patients who received celecoxib and in 5 patients who received placebo, respectively. Compared with those who received placebo, patients who received celecoxib had no signif icant increase in occurrence of CV events (hazard ratio = 0.84, 95% CI = 0.23-3.15). Among the adverse events acquired by interview survey, only the frequency of bloating was signif icantly higher in patients treated with celecoxib than in those treated with placebo. CONCLUSION: Treatment of gastric cancer with celecoxib is not associated with increased risk of gastroduodenal ulcer and cardiovascular events.

关键词： Celecoxib Gastroduodenal ulcer Cardiovascular diseases Adverse effects Epidemiology Randomized controlled trial

Effect of angiotensin II type I receptor blocker losartan on bone deterioration in orchiectomized male hypertensive and normotensive rats

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Chinese Medical Journal 2013年第14期126卷 2661-2665页

作者： ZHANG Ya-feng QIN Ling Timothy cy Kwok Benson HY Yeung LI Guo-dong LIU Fan Department of Orthopaedics The Affiliated Hospital to Nantong University Nantong Jiangsu 226001 China Department of Medicine and Therapeutics Prince of Wales Hospital The Chinese University of Hong Kong Shatin N.T. Hong Kong China Department of Orthopaedics and Traumatology Prince of Wales Hospital The Chinese University of Hong Kong Shatin N.T. Hong Kong China

Background Epidemiological study showed that the use of angiotensin-converting enzyme inhibitors was associated with higher bone mineral density （BMD） in older people, especially male subjects, which suggested that angiotensin II may have a detrimental effect on bone. Therefore, blocking its effect may have a beneficial effect on bone health. Methods Six-month-old male spontaneously hypertensive rats （SHR） and normotensive Wistar Kyoto rats （WKY） were used. Animals of each model were randomly assigned to the following four groups： Group 1, SHAM operated＋vehicle; Group 2, orchidectomy （ORX）＋vehicle; Group 3, ORX＋low-dose Iosartan （10 ***）; and Group 4, ORX＋high-dose Iosartan （25 mg-kg-l.d-1）. Blood pressure was recorded weekly. SHAM and ORX operations were performed, followed by daily Iosartan and vehicle treatment from day 4 after operation for 16 weeks. Serum and 24-hour urine samples were collected for measurement of bone turnover markers before euthanasia and then the left femur was collected for measurements of BMD and microarchitecture before mechanical test. Results Urine deoxypyridinoline/urine creatinine （DPD/Cr） ratio was significantly higher in SHR than in WKY. BMD and microarchitecture parameters also showed bone deterioration in SHR. After ORX, serum osteocalcin concentration decreased and urine DPD/Cr ratio increased significantly accompanied by a significant decrease in cortical and trabecular BMD and cortical bone thickness in both WKY and SHR. High-dose Iosartan significantly increased DPD in urine in both SHR and WKY. Apart from marginal favorable changes in bone architecture in WKY treated with high-dose Iosartan, Iosartan did not show significant effect on BMD, bone area, bone microarchitecture, and mechanical properties in both SHR and WKY. Conclusion Angiotensin II type I receptor blocker Iosartan was not able to demonstrate significant effect on ORX-induced bone deterioration in both hypertensive and normotensive rats.

关键词： angiotensin angiotensin II type I receptor blocker osteoporosis orchidectomy rat

An economic analysis of twenty light olefin production pathways

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Journal of Energy Chemistry 2021年第5期30卷 193-202页

作者： Zhitong Zhao Jingyang Jiang feng Wang State Key Laboratory of Fine Chemicals College of ChemistryFaculty of Chemical Environmental and Biological Science and TechnologyDalian University of TechnologyDalian 116024LiaoningChina State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China

A comprehensive economic analysis of twenty light olefin production pathways has been performed,covering current and promising processes from fossil(petroleum,coal and natural gas)and renewable resources(biomass and CO_(2)).Taking steam cracking of naphtha as the benchmark,this study gives an economic perspective and points out the bottleneck in different olefin production *** assessment indicates that nearly all renewable pathways are economically unattractive currently and the raw material cost accounts for dominant contribution in most pathways,especially in the oil-,natural gas-and CO_(2)-derived *** the ways of methanol-to-olefins and methanol-to-propylene,fossil pathways are cost-competitive according to the date of current Chinese market ***,the price of feedstock hydrogen needs to be lowered by 55%to fill the cost gap between CO_(2)-derived pathways and the *** the ways of oxidative coupling of methane and Fischer-Tropsch synthesis to olefins,fossil pathways enable cost-competitive processes by feedstock price fall,but further process improvement is required to approach benchmark in renewable ***,a decrease in ethanol price by45%can make ethanol dehydration pathway *** addition,costs can reduce by 4%-23%in different pathways as the production scales expand from 100 to 1000 kt/a,resulting in a change from high cost to economic profit for some of the *** results quantify the need for improvements on feedstock price,scale size and process improvement to achieve competitive production costs.

关键词： Ethylene Propylene Olefin Techno-economic Conceptual design

Metal-Carbene-TempIated Photochemistry in Solution: A Universal Route towards cyclobutane Derivatives

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Chinese Journal of Chemistry 2019年第11期37卷 1147-1152,I0002页

作者： Yang Li Guang-feng Jin Yuan-Yuan An Rajorshi Das Ying-feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry College of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

Background and Originality Content cyclobutane moieties are an important class of motifs since they are frequently found in the medicinally relevant compounds such as alkaloids and pharmaceuticals.[1] Therefore,the development of efficient synthetic strategies for the construction of cyclobutanes and their derivatives has always been a focus of inter-est.[2a] Photochemical reactions are powerful tools for synthesizing compounds with high complexity and diversity.[2b-h] Among them,photochemical[2+2]cycloaddition is a widely used protocol for the preparation of such compounds.[2h]However,this kind of reaction always suffers from the challenges of controlling the resulting products of the intermolecular[2+2]*** principle,to achieve cyclobutanes via[2+2]cycloaddition,the two olefins should be oriented in a parallel fashion keeping the distance less than 4.2 A apart from each other.

关键词： butane photochemical alkaloids

Advances and Challenges of Photocatalytic Methane C—C Coupling

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Chinese Journal of Chemistry 2022年第12期40卷 1492-1505页

作者： Xueyuan Wang Nengchao Luo feng Wang State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China Zhang Dayu School of Chemistry Dalian University of TechnologyDalianLiaoning 116024China University of Chinese Academy of Sciences Beijing 100049China

Methane,the main component of natural gas and shale gas,can be converted to upgraded fuels,syngas and value-added *** to the nonpolar character of methane and large bond dissociation energy of sp^(3)C—H bond,methane conversion requires strong oxidants or acids/bases for its *** capable of inducing highly oxidative surrogates enables methane C—H bond scission at room temperature,thereby avoiding side reactions and coke formation caused by high reaction *** scission of methane C—H bond generates·CH_(3)that may undergo C—C bond coupling with carbon radicals,which is a versatile way to obtain C_(2+)*** from the kinetically slow activation of methane C—H bond,photocatalysis also suffers from complex product distributions owing to the presence of varieties of radicals during photocatalytic methane conversion,and a low selectivity of desired C_(2+)products was *** this review,we summarize the recent advances of photocatalytic methane conversion with emphasis on methane C—C bond *** of methane C—H bond activation and radical manipulation for selective C—C bond cou-pling were discussed in *** hope this review may be a valuable guide of future work in photocatalytic methane C—C coupling.

关键词： Photocatalysis Methane CC Coupling CH activation Oxidant

Difference in gene expression of macrophage between normal spleen and portal hypertensive spleen idendified by cDNA microarray

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World Journal of Gastroenterology 2007年第24期13卷 3369-3373页

作者： feng Yan Xiao-Min Wang Postdoctoral Station Department of Hepato-Biliary Surgery Zhongshan Hospital Xiamen University Xiamen 361004 Fujian Province China Department of Hepato-Biliary Surgery Zhongshan Hospital Xiamen University Xiamen 361004 Fujian Province China

AIM: To identify the difference in gene expression of microphage (Mφ) between normal spleen and portal hypertensive spleen using cDNA microarrays and find new gene functions associated with hypersplenism in portal hypertension. METHODS: The Biostar-H140s chip containing 14 112 spots of cDNAs were used to investigate the difference of the expression. The total RNA extracted from macrophages isolated from both normal spleen and portal hypertensive spleen was reversely transcribed to cDNA with the incorporation of fluorescent (cy3 and cy5) labeled dCTP to prepare the hybridization probes. After hybridization, the gene chip was scanned for the fluorescent intensity. The differentially expressed genes were screened. That was repeated three times, and only the genes which had differential expression in all three chips were considered to be associated with hypersplenism in portal hypertension. RESULTS: Eight hundred and ninety-six, 1330 and 898 genes were identified to be differentially expressed in three chips, respectively. One hundred and twenty-one genes (0.86%) were identified to be differentially expressed in all three chips, including 21 up-regulated genes and 73 down-regulated genes. The differentially expressed genes were related to ionic channel and transport protein, cyclin, cytoskeleton, cell receptor, cell signal conduct, metabolism, immune, and so on. These genes might be related to the hypersplenism in portal ***: The investigations based on cDNA microarray can screen differentially expressed genes of macrophages between normal spleen and portal hypertensive spleen, thus may provide a new idea in studying the pathogenesis of hypersplenism in portal hypertension.

关键词： Hypersplenism Macrophage cDNA microarray

Association of differentially expressed genes with activation of mouse hepatic stellate cells by high-density cDNA mircoarray

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World Journal of Gastroenterology 2004年第11期10卷 1600-1607页

作者： Xiao-JingLiu LiYang feng-MingLuo Hong-BinWu Qu-Qiang LaboratoryofDepartmentofInternalMedicine WestChinaHospitalSichuanUniversityChengdu610041SichuanProvinceChina DepartmentofGastroenterologyofWestChinaHospital SichuanUniversityChengdu610041SichuanProvinceChina DepartmentofInternalMedicineofWestChinaHospital SichuanUniversityChengdu610041SichuanProvinceChina

AIM: To characterize the gene expression profiles associated with activation of mouse hepatic stellate cell (HSC) and provide novel insights into the pathogenesis of hepatic fibrosis. METHODS: Mice HSCs were isolated from BALB/c mice by in situ perfusion of collagenase and pronase and singlestep density Nycodenz gradient. Total RNA and mRNA of quiescent HSC and culture-activated HSC were extracted, quantified and reversely transcripted into cDNA. cDNAs from activated HSC were labeled with cy5 and cDNAs from the quiescent HSC were labeled with cy3, which were mixed with equal quantity, then hybridized with cDNA chips containing 4 000 genes. Chips were washed, scanned and analyzed. Increased expression of 4 genes and decreased expression of one gene in activated HSC were confirmed by reverse transcription- polymerase chain reaction (RT-PCR). RESULTS: A total of 835 differentially expressed genes were identified by cDNA chip between activated and quiescent HSC, and 465 genes were highly expressed in activated HSC. The differentially expressed genes included those involved in protein synthesis, cell-cycle regulation, apoptosis, and DNA damage response. CONCLUSION: Many genes implicated in intrahepatic inflammation, fibrosis and proliferation were up-regulated in activated HSC. cDNA microarray is an effective technique in screening for differentially expressed genes betweentwo different situations of the HSC. Further analysis of the obtained genes will help understand the molecular mechanism of activation of HSC and hepatic fibrosis.

关键词：基因表达老鼠肝星形细胞高密度cDNA 活化作用肝纤维化

Effect of sintering temperature on the microstructure and properties of foamed glass-ceramics prepared from high-titanium blast furnace slag and waste glass

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International Journal of Minerals,Metallurgy and Materials 2017年第8期24卷 931-936页

作者： Chang-hong Chen Ke-qin feng Yu Zhou Hong-ling Zhou School of Manufacturing Science and Engineering Sichuan University

Foamed glass-ceramics were prepared via a single-step sintering method using high-titanium blast furnace slag and waste glass as the main raw materials The influence of sintering temperature(900–1060℃) on the microstructure and properties of foamed glass-ceramics was studied. The results show that the crystal shape changed from grainy to rod-shaped and finally turned to multiple shapes as the sintering temperature was increased from 900 to 1060℃. With increasing sintering temperature, the average pore size of the foamed glass-ceramics increased and subsequently decreased. By contrast, the compressive strength and the bulk density decreased and subsequently increased. An excessively high temperature, however, induced the coalescence of pores and decreased the compressive strength. The optimal properties, including the highest compressive strength(16.64 MPa) among the investigated samples and a relatively low bulk density(0.83 g/cm^3), were attained in the case of the foamed glass-ceramics sintered at 1000℃.

关键词： foamed glass-ceramics sintering temperature blast furnace slag waste glass crystallization