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Aberrant histone H4 acetylation in dead somatic cell-cloned calves

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Progress in Natural science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing 100094, china b Beijing Gene & Protein Biotechnology Co. LTD, Beijing 100094, china c college of animal science and technology, china agricultural university, Beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China college of animal science and technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

Production of porcine cloned transgenic embryos expressing green fluorescent protein by somatic cell nuclear transfer

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science china(Life sciences) 2006年第2期49卷 164-171页

作者： ZHANG Yunhai1, PAN Dengke1,2, SUN Xiuzhu1, SUN Guojie1, WANG Xiaobo1, LIU Xiaohui1, LI Yan1, DAI Yunping1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing 100094, china 2. college of animal science and technology, china agricultural university, Beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China college of animal science and technology China Agricultural University Beijing China

In the present study, nuclear transferred embryos (NTEs) were reconstructed by using pig fetal fibroblasts as donors; in vitro matured oocytes as recipients. The effects of G418 selection on donor cells, duration of IVM of prepubertal gilt oocytes; oxygen tension in IVM of oocytes were investigated. The results were as follows: (i) When G418 selected cells expressing GFP were used as donors, the cleavage rate of NTEs decreased drastically in comparison to NTEs derived from donors without antibiotic selection (47.5% vs. 71.6%, p>0.05). For the blastocyst rate, no significant difference was observed between two groups (10% vs. 10.4%, p0.05). However, no statistical difference was observed between NTEs derived from oocytes of 36 h IVM group; NTEs from oocytes of 42 h IVM group in the rates of cleavage (59.3% vs. 73.6%, p<0.05); blastocyst formation (9.3% vs. 13.2%, p<0.05); (iii) no significant difference was observed between NTEs reconstructed from oocytes matured under lower oxygen (7% O2) tension; NTEs derived from oocytes matured under higher oxygen tension (20% O2) in cleavage rate (70.6% vs. 67.1%, p<0.05); blastocyst rate (11.8% vs. 12.3%, p<0.05). These results suggest that: (i) G418 selection does not have a significant effect on cleavage rate of NTEs expressing GFP. (ii) Nuclear maturation is greatly improved by prolonging IVM duration from 36 to 42 h, while no significant differences were observed for developmental potential of transgenic embryos. Thus IVM 42 h is the better choice in order to obtain maximum number of MII oocytes as recipients. (iii) Lower oxygen tension; higher oxygen tension in IVM have no significant effect on development of cloned embryos.

关键词： transgenic cloning, GFP, Pig, early development.

Cloning, sequencing and identification of single nu-cleotide polymorphisms of partial sequence on the porcine CACNA1S gene

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science china(Life sciences) 2008年第4期51卷 317-325页

作者： FANG XiaoMin1,2, XU NingYing2 & REN ShouWen1 1 Institute of animal science, Jiangsu Academy of agricultural sciences, Nanjing 210014, china 2 college of animal science, Zhejiang university, Hangzhou 310029, china Institute of animal science Jiangsu Academy of Agricultural Sciences Nanjing China college of animal science Zhejiang University Hangzhou China

CACNA1S gene encodes the α1 subunit of the calcium channel. The mutation of CACNA1S gene can cause hypokalemic periodic paralysis (HypoKPP) and maliglant hyperthermia synarome (MHS) in hu-man beings. Current research on CACNA1S was mainly in human being and model animal, but rarely in livestock and poultry. In this study, Yorkshire pigs (23), Pietrain pigs (30), Jinhua pigs (115) and the second generation (126) of crossbred of Jinhua and Pietrain were used. Primers were designed ac-cording to the sequence of human CACNA1S gene and PCR was carried out using pig genome DNA. PCR products were sequenced and compared with that of human, and then single nucleotide poly-morphisms (SNPs) were investigated by PCR-SSCP, while PCR-RFLP tests were performed to validate the mutations. Results indicated: (1) the 5211 bp DNA fragments of porcine CACNA1S gene were ac-quired (GenBank accession number: DQ767693 ) and the identity of the exon region was 82.6% be-tween human and pig; (2) fifty-seven mutations were found within the cloned sequences, among which 24 were in exon region; (3) the results of PCR-RFLP were in accordance with that of PCR-SSCP. Ac-cording to the EST of porcine CACNA1S gene published in GenBank (Bx914582, Bx666997), 8 of the 11 SNPs identified in the present study were consistent with the base difference between two EST frag-ments.

关键词： pig calcium channel α1 subunit (CACNA1S) single nucleotide polymorphism (SNP) PCR-SSCP PCR-RFLP

Unscented Kalman filtering in the additive noise case

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science china(Technological sciences) 2010年第11期53卷 929-941页

作者： LIU Ye1,YU AnXi1,ZHU JuBo2 & LIANG DianNong1 1 college of Electronic science and Engineering,National university of Defense technology,Changsha 410073,china 2 science college,National university of Defense technology,Changsha 410073,china college of Electronic science and Engineering National University of Defense Technology Changsha China science college National University of Defense Technology Changsha China

The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation *** paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,*** conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly ***,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process *** is not believed to be necessary in some ***,we find out that resampling can be helpful for an adaptive Kalman *** will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers ***,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it's better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent.

关键词： unscented Kalman filter additive noise unscented transformation augmented redraw sigma points adaptive

Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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science china(Technological sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular Engineering,Qingdao university of science & technology,Qingdao,china 2 college of Information science & technology,Qingdao university of science & technology,Qingdao,china Institute of Chemistry & Molecular Engineering Qingdao University of Science & Technology Qingdao China college of Information science & technology Qingdao University of Science & Technology Qingdao China

At the end of the 1950s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465―1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

One-pot synthesis of crystalline SnO_2 nanoparticles and their low-temperature ethanol sensing characteristics

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science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1601-1605页

作者： CHEN YuJin1,2,3,ZHU ChunLing4,WANG LiJiao3 & WANG TaiHong2 1 School of Materials science and Engineering,Beijing Institute of technology,Beijing 100081,china 2 Micro-Nano Technologies Research Center,Hunan university,Changsha 410082,china 3 college of science,harbin Engineering university,harbin 150001,china 4 college of Material science and Chemical Engineering,harbin Engineering university,harbin 150001,china School of Materials science and Engineering Beijing Institute of Technology Beijing China Micro-Nano Technologies Research Center Hunan University Changsha China college of science Harbin Engineering University Harbin China college of Material science and Chemical Engineering Harbin Engineering University Harbin China

Crystalline SnO2 nanoparticles(NPs) with a diameter less than 6 nm are synthesized using potassium stannate trihydrate as the precursor in a basic *** synthesized NPs can detect ethanol at a ppm level even at 100℃.Furthermore,the NPs have good selectivity to *** excellent ethanol sensing performances are attributed to the small size effect according to the space-charge model.

关键词： SnO2 nanoparticles sensing characteristics

Representation and Adaptive Transformation of Reusable Software Components

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 298-303页

作者： Xu Zheng quan, Palakiyem Wallah college of Computer science and technology,Huazhong university of science and technology, Wuhan 430074, china college of Computer science and technology Huazhong University of Science and Technology Wuhan China

The key ingredient for promoting software reuse in a repository base integrated development environment, is to provide support for the software developer who wants to search the repository to locate and retrieve suitable software components for reuse. This paper presents that reusable software components form a base to provide a flexible representation of component adaptability to any repository with a specific classification. As an alternative, it proposes to automatically identify and convert the component source code with all its information into a standard form, so that components can be transferred from one type of library to another.

关键词： reusable software component classification representation adaptability transfer

NUMERICAL SIMULATION OF SLOSHING IN RECTANGULAR TANK WITH VOF BASED ON UNSTRUCTURED GRIDS

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Journal of Hydrodynamics 2010年第6期22卷 856-864页

作者： MING Ping-jian DUAN Wen-yang college of Power and Energy Engineering Harbin Engineering University Harbin 150001 China college of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

A new method for sloshing simulation in a sway tank is present, in which the two phase interface is treated as a physical discontinuity, which can be captured by a well-designed high order scheme. Based on Normalized Variable Diagram （NVD）, a high order discretization scheme with unstructured grids is realized, together with a numerical method for free surface flow with a fixed grid. This method is implemented in an in-house code General Transport Equation Analyzer （ GTEA ） which is an unstructured grids finite volume solver. The present method is first validated by available analytical solutions. A simulation for a 2-D rectangular tank at different excitation frequencies of the sway is carried out. A comparison with experimental data in literature and results obtained by commercial software CFX shows that the sloshing load on the monitor points agrees well with the experimental data, with the same grids, and the present method gives better results on the secondary peak. It is shown that the present method can simulate the free surface overturning and breakup phenomena.

关键词： sloshing numerical simulation unstructured grid Volume Of Fluid (VOF)

The Effect of Chitosan and Sodium Alginate on the Root Growth and Enzyme Activity of Soybean

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Journal of northeast agricultural university(English Edition) 2002年第1期9卷 16-21页

作者： WANG Hong yan,PENG Chi (college of resources and environment science,northeast agricultural university, harbin 150030,P.R.china) college of resources and environment science Northeast Agricultural University Harbin 150030P.R. China

The resaerch examined the effect of the two oceanic materials as coating materials on the soybean *** results showed chitosan and sodium alginate seed coating can enhance the growth of seedling root,increase the nodule mumber,root activity and the growth of *** suggested coating ratios were 0.5～1.0g/kgseed,the same as *** two materials could increase the contents of CAT and NR in soybean leaves,decrease the contents of POD in soybean leaves.

关键词： chitosan sodium alginate soybean activity CAT POD NR