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Structural,thermodynamic and electronic properties of zinc-blende AlN from first-principles calculations

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Chinese Physics B 2009年第3期18卷 1207-1213页

作者：张伟程艳朱俊陈向荣 Institute of Atomic and molecular Physics Sichuan University International centre for Materials Physics Chinese Academy of Sciences

Structural, thermodynamic and electronic properties of zinc-blende AIN under pressure are investigated by first- principles calculations based on the plane-wave basis set. Through the analysis of enthalpy variation of AIN in the zinc-blende （ZB） and the rock-salt （RS） structures with pressure, we find the phase transition of A1N from ZB to RS structure occurs at 6.7GPa. By using the quasi-harmonic Debye model, we obtain the heat capacity Cv, Debye temperature θD, Gruneisen parameter γ and thermal expansion coefficient α. The electronic properties including fundamental energy gaps and hydrostatic deformation potentials are investigated and the dependence of energy gaps on pressure is analysed.

关键词： local density approximation (LDA) thermodynamic properties band structure A1N

TFIIA transcriptional activity is controlled by a ＇cleave-and-run＇ Exportin-1/Taspase 1-switc

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Journal of molecular Cell Biology 2018年第1期10卷 33-47页

作者： Christian Schrenk Verena Fetz Cecilia Vallet Christina Heiselmayer Elisabeth Schroder Astrid Hensel Angelina Hahlbrock Desiree Wunsch Dorothee Goesswein Carolin Bier Negusse Habtemichael Gunter Schneider Roland H. Stauber Shirley K. Knauer molecular and Cellular oncology/ENT University Hospital of Mainz 55101 Mainz Germany molecular Biology Centre for Medical Biotechnology (ZMB) University Duisburg-Essen 45141 Essen Germany University Hospital Klinikum rechts der Isar II. Medizinische Klinik Technical University Mfinchen 81675 Munich Germany

Transcription factor TFIIA is controlled by complex regulatory networks including proteolysis by the protease Taspase 1, though the full impact of cleavage remains elusive. Here, we demonstrate that in contrast to the general assumption, de novo produced TFIIA is rapidly confined to the cytoplasm via an evolutionary conserved nuclear export signal （NES, amino acids ^21VINDVRDIFL^30）, interacting with the nuclear export receptor Exportin-1/chromosomal region maintenance 1 （Crml）. Chemical export inhibition or genetic inactivation of the NES not only promotes TFIIA＇s nuclear localization but also affects its transcrip- tional activity. Notably, Taspase 1 processing promotes TFIIA＇s nuclear accumulation by NES masking, and modulates its tran- scriptional activity. Moreover, TFIIA complex formation with the TATA box binding protein （TBP） is cooperatively enhanced by inhibition of proteolysis and nuclear export, leading to an increase of the ceil cycle inhibitor p16INK, which is counteracted by pre- vention of TBP binding. We here identified a novel mechanism how proteolysis and nuclear transport cooperatively fine-tune tran- scriptional programs.

关键词： cdnka2 cell cycle Crml nuclear export proteolysis TBP

Effect of local structure on electron paramagnetic resonance spectra for trigonal [Cr(H_2O)_6]^(3+) coordination complex in the sulfate alums series:a ligand field theory study

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Chinese Physics B 2009年第7期18卷 2967-2974页

作者：李艳芳邝小渝高明亮赵亚儒王怀谦 Institute of Atomic and molecular Physics Sichuan University International centre for Materials Physics Chinese Academy of Sciences

A simple theoretical method is introduced for studying the interrelation between electronic and molecular *** diagonalizing the 120 × 120 complete energy matrices,the relationships between zero-field splitting （ZFS） parameter D and local distortion parameter △θ for Cr^3＋ ions doped,separately,in α- and β- alums are *** results indicate that there exists an approximately linear relationship between D and △θ in a temperature range 4.2-297 K and the signs of D and △θ are opposite to each ***,in order to understand the contribution of spin-orbit coupling coefficient ζ to ZFS parameter D,the relation between D and ζ is also discussed.

关键词： complete energy matrices electron paramagnetic resonance (EPR) spectra local structure

A tRF oligomerizes Nucleolin to stabilize metastasis-favoring transcripts

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Science China(Life Sciences) 2023年第3期66卷 646-648页

作者： Jiawei Guo Yong Peng Laboratory of molecular oncology Frontiers Science Center for Disease-related Molecular Network State Key Laboratory of Biotherapy and Cancer Center West China Hospital Sichuan University

Apart from bringing amino acids to ribosomes for protein biogenesis,transfer RNA(t RNA)can be cleaved into small non-coding RNAs,named as t RFs or ts *** small RNA fragments were firstly thought as random degradation products of t RNAs until the induction of certain t RFs were observed in specific stress conditions(Li et al.,2008).

关键词： metastasis bringing

The current status of anti-GPCR drugs against different cancers

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Journal of Pharmaceutical Analysis 2020年第6期10卷 517-521页

作者： Sana Usman Maria Khawer Shazia Rafique Zara Naz Komal Saleem centre for Applied molecular Biology 87-West Canal Bank Road Thokar Niaz BaigUniversity of the PunjabLahorePakistan centre of Excellence in molecular Biology University of the PunjabLahorePakistan

G protein coupled receptors(GPCRs)have emerged as the most potential target for a number of drug discovery programs ranging from control of blood pressure,diabetes,cure for genetic diseases to treatment of cancer.A panel of different ligands including hormones,peptides,ions and small molecules is responsible for activation of these *** genetics has identified key GPCRs,whose mutations or altered expressions are linked with *** this review,we discussed recent advances regarding the involvement of GPCRs in the development of cancers and approaches to manipulating the mechanism behind GPCRs involved tumor growth and metastasis to treat different types of human *** review provides an insight into the current scenario of GPCR-targeted therapy,progress to date and the challenges in the development of anticancer drugs.

关键词： GPCRs Anticancer therapy Pancreatic cancer Colon cancer CLL Prostate cancer Melanoma

Characterization of lipid parameters in diabetic and non-diabetic atherosclerotic patients

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Journal of Geriatric Cardiology 2015年第1期12卷 37-43页

作者： Fatima Ali Hassan Jamil Sanam Saiqa Anwar Nadia Wajid Institute of molecular Biology and Biotechnology (IMBB) & centre for Research in molecular Medicine (CRIMM) University of Lahore 1-Kin Defence Road Lahore Pakistan

Background ＆ Objective The relationship between lipid profile perturbation and diabetes associated complications has long been an area of interest. Dyslipidemia is a potent predictor of cardiovascular morbidity and mortality in diabetic patients. The aim of present study was to investigate relationship between aging and lipid profiles in diabetic and non-diabetic atherosclerotie patients. Methods Five hundred and seventy six individuals （45-75 year age） participated in this study. Among these, 192 were having history of diabetes mellitus and atherosclerosis. Individuals are categorized on the base of health （normal, non-diabetic atheroselerosis, diabetic atherosclerosis） and age （45-55 years, 56~55 years, and 66-75 years）. All the participants were subjected to the procedures like a detailed history, biochemical analysis for fasting blood sugar, hemoglobin Alc, total cholesterol （TC）, triglycerides （TG）, low-density lipoprotein-（LDL）, very low-density lipoprotein （VLDL） and high-density lipoprotein （HDL）. All these parameters were compared between diabetic and non-diabetic atherosclerotic patients of all three age groups. TC/HDL and LDL/HDL were also calculated. Results Diabetic atherosclerotic individuals （both males and females） had high level of TC, TG, LDL, VLDL and low level of HDL in comparison to non-diabetic atherosclerotie and normal control individuals. Among all three age groups, lipoprotein abnormality was observed to be more frequent in females than males. There was a significant increase in TC/HDL and LDL/HDL ratio in diabetic atherosclerotic subjects compared to age and sex matched non-diabetic atherosclerotic and normal control. Conclusions Degree of dyslipidemia increases with increase in age in both genders. Female are more prone to diabetic dyslipidemia and hence have more risk of developing atherosclerosis with increasing age.

关键词： Aging Atherosclerosis Diabetes Dyslipidemia

Oxygation Enhances Growth,Gas Exchange and Salt Tolerance of Vegetable Soybean and Cotton in a Saline Vertisol

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Journal of Integrative Plant Biology 2009年第7期51卷 675-688页

作者： Surya P. Bhattarai David J. Midmore centre for Plant and Water Science Department of Molecular and Life SciencesCentral Queensland University

Impacts of salinity become severe when the soil is deficient in oxygen. OxygaUon （using aerated water for subsurface drip irrigation of crop） could minimize the impact of salinity on plants under oxygen-limiting soil environments. Pot experiments were conducted to evaluate the effects of oxygation （12% air volume/volume of water） on vegetable soybean （moderately salt tolerant） and cotton （salt tolerant） in a salinized vertisol at 2, 8, 14, 20 dS/m ECe. In vegetable soybean, oxygation increased above ground biomass yield and water use efficiency （WUE） by 13% and 22%, respectively, compared with the control. Higher yield with oxygation was accompanied by greater plant height and stem diameter and reduced specific leaf area and leaf Na^＋ and CI^- concentrations. In cotton, oxygation increased lint yield and WUE by 18% and 16%, respectively, compared with the control, and was accompanied by greater canopy light interception, plant height and stem diameter. Oxygation also led to a greater rate of photosynthesis, higher relative water content in the leaf, reduced crop water stress index and lower leaf water potential. It did not, however, affect leaf Na^＋ or CI^- concentration. Oxygation invariably increased, whereas salinity reduced the K^＋： Na^＋ ratio in the leaves of both species. Oxygation improved yield and WUE performance of salt tolerant and moderately tolerant crops under saline soil environments, and this may have a significant impact for irrigated agriculture where saline soils pose constraints to crop production.

关键词： cotton irrigation light interception oxygation saline soil salt exclusion stem diameter vegetable soybean

Alginate nanobeads interspersed fibrin network as in situ forming hydrogel for soft tissue engineering

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Bioactive Materials 2018年第2期3卷 194-200页

作者： S.Deepthi R.Jayakumar centre for Nanosciences and molecular Medicine Amrita UniversityKochi682041India

Hydrogels are a class of materials that has the property of injectability and in situ gel *** property of hydrogels is manipulated in this study to develop a biomimetic bioresorbable injectable system of alginate nanobeads interspersed in fibrin *** nanobeads developed by calcium cross-linking yielded a size of 200e500 *** alginate nanobeads fibrin hydrogel was formed using dual syringe *** of the in situ injectable hydrogel was done by SEM,FTIR and *** developed hydrogel showed mechanical strength of 19 kPa which provides the suitable compliance for soft tissue *** studies using human umbilical cord blood derived mesenchymal stem cells showed good attachment,proliferation and infiltration within the hydrogel similar to fibrin *** developed in situ forming hydrogel could be a suitable delivery carrier of stem cells for soft tissue regeneration.

关键词： Alginate nanobeads Fibrin hydrogel Soft tissue engineering

Expression of vascular endothelial growth factor and its receptors KDR and Fit-1 in gastric cancer cells

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World Journal of Gastroenterology 2002年第6期8卷 994-998页

作者： Hua Zhang Jian Wu Lin Meng Cheng-Chao Shou,Peking University School ofoncology,Beij ing Institute for Cancer Research,Beijing 100034,China Department of Biochemistry and molecular Biology Peking University School of Oncology Beijing Institute for Cancer Research China.

AIM: The expression of vascular endothelial growth factor (VEGF) and its receptors KDR and Flt-1 by gastric carcinoma tissues and different gastric carcinoma cell lines was detected to elucidate the molecular mechanism of this growth factor in promoting tumor ***: The expression of VEGF, Flt-1 and KDR was determined by reverse transcription-polymerase chain reaction (RT-PCR) in gastric cancer cell lines RF-1, RF-48,AGS-1, NCI-N87, NCI-SNU-1, NCI-SNU-5, NCI-SNU-16 and KATO-Ⅲ. The expression of Flt-1 and KDR in paraffinembedded specimens of gastric cancer was determined by immunohistochemistry. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess the role of VEGF in tumor cell ***: All 8 gastric cancer cell lines analyzed expressed VEGF121 and VEGF16s and six of them expressed both Flt-1 and KDR, while cell line NCI-SNU-5 expressed Flt-1 only and cell line KATOⅢ expressed neither Flt-1 nor KDR. The gastric carcinoma tissues expressed Flt-1 and KDR widely,with the positive rate of expression of Flt-1 and KDR being 84.6 % and 70 % respectively. The exogenous VEGF stimulated the growth of KDR-positive cell lines NCI-N87 and AGS-1 in a dose-dependent manner but exhibited no effect on the growth of KDR-negative cell line ***: VEGF and its receptors KDR and Flt-1 were expressed widely in gastric carcinoma cells and the VEGF stimulated KDR-positive tumor cell growth directly. These results suggest that VEGF may play a role in promoting tumor growth and metastasis by participating in both paracrine and autocrine pathways.

关键词：血管内皮生长因子 VEGF受体 KDR Flt-1 胃癌细胞基因表达