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Journal of University of Science and Technology Beijing 2005年第6期12卷 564-571页

作者： Junsheng Wu Xiaogang Li wei Du hua chen Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing C16EO15 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.

关键词： silica sol-gel phase separation macroporous gel morphology nonionic surfactant

Separation of growth-stimulating peptides for Bifidobacterium from soybean conglycinin

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World Journal of Gastroenterology 2005年第37期11卷 5801-5806页

作者： wei-Yong Zuo wei-hua chen Si-Xiang Zou Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture College of Veterinary Medicine Nanjing Agricultural University Nanjing 210095 Jiangsu Province China

AIM： To isolate and identify the soybean conglycinin peptides that selectively stimulates the growth of bifidobacteria in vitro, and to investigate the effect of soybean conglycinin peptides on intestinal ecosystem in vivo. METHODS： Soybean conglycinin was purified from soybean seeds by gel filtration （Sepharose-CL-6B）. These proteins were submitted to hydrolysis by pepsin. Several growth-stimulating peptides for bifidobacteria were isolated chromatographically from pepsin hydrolysis of soybean conglycinin and identified by means of matrixassisted laser desorption ionization time of flight mass spectrometry （MALDI-TOF-MS）. Parallel to in vitro study, in vivo experiments with soybean conglycinin peptides were performed in mice. Ninety male KM mice were randomly assigned into five groups of 16 mice each, and each group was administered for 21d intragastrically with physiological saline （control）, conglycinin, pepsin-treated conglycinin （PTC）, the most active fraction which isolated from pepsin-treated conglycinin （P2-PTC） and HCl-full hydrolysis of conglycinin （HCl-FHC）, respectively. Intestinal microflora were evaluated by standard microbiologic methods and biochemical assays of cecal content samples after treatment. RESULTS： The results showed that the peptides which were isolated from soybean conglycinin could stimulate the growth of bifidobacteria in vitro, and the molecular mass of purified peptides with MALDI-TOF-MS ranged from 693.32 to 1829.55. Compared with control group, in vivo experiments showed that P2-PTC group decreased cecal pH （7.08±0.08 vs7.21±0.09, P〈0.05） and enterococcicounts （5.38±0.26 log10CFU/g vs 5.78±0.19 log10CFU/g, P〈0.05）, significantly increased sIgA level （172.08±35.40 ng/g vs 118.27±33.93 ng/g, P〈0.01） and β-galactosidase activity （1.28±0.23 U/g vs 1.82±0.58 U/g, P〈0.05） CONCLUSION： The results have shown that conglycinin is good source for enzyme-mediated production of peptides which stimulate the growth of bifidobacteria. These peptid

关键词： Conglycinin pepsin peptides bifidobacteria

GAAD: A Gene and Autoimmiune Disease Association Database

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Genomics, Proteomics & Bioinformatics 2018年第4期16卷 252-261页

作者： Guanting Lu Xiaowen Hao wei-hua chen Shijie Mu Department of Blood Transfusion Tangdu Hospital Fourth Military Medical University MOE Key Laboratory of Molecular Biophysics Hubei Key Laboratory of Bioinformatics and Molecular-imaging Department of Bioinformatics and Systems Biology College of Life Science and Technology Huazhong University of Science and Technology

Autoimmune diseases （ADs） arise from an abnormal immune response of the body against substances and tissues normally present in the body. More than a hundred of ADs have been described in the literature so far. Although their etiology remains largely unclear, various types of ADs tend to share more associated genes with other types of ADs than with non-AD types. Here we present GAAD, a gene and AD association database. In GAAD, we collected 44,762 associations between 49 ADs and 4249 genes from public databases and MEDLINE documents. We manually verified the associations to ensure the quality and credibility. We reconstructed and recapitulated the relationships among ADs using their shared genes, which further validated the quality of our data. We also provided a list of significantly co-occurring gene pairs among ADs;with embedded tools, users can query gene co-occurrences and construct customized cooccurrence network with genes of interest. To make GAAD more straightforward to experimental biologists and medical scientists, we extracted additional information describing the associations through text mining, including the putative diagnostic value of the associations, type and position of gene polymorphisms, expression changes of implicated genes, as well as the phenotypical consequences, and grouped the associations accordingly. GAAD is freely available at http：//***.

关键词： Autoimmune diseases Disease-gene association Database Text mining

Osteochondral Integrated Scaffolds with Gradient Structure by 3D Printing Forming

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International Journal of Automation and computing 2015年第2期12卷 220-228页

作者： wei-hua chen Yuan-Yuan Liu Fu-hua Zhang Yong-Ze Yu Hai-Ping chen Qing-Xi Hu Rapid Manufacturing Engineering Center Shanghai University

Recently in the area of biological manufacturing and rapid prototyping manufacturing, the bone scaffolds based on the additive manufacturing in repairing bone defects have been paid more and more attention. In the process of preparation, path planning directly affects the structure, performance as well as the final bone cell culture conditions. Due to the special natural bone scaffold structural characteristic, the traditional rapid prototyping(RP) path planning is not fully suitable for the preparation of bone scaffolds. In this paper, based on the 3D printing extrusion forming technology, a method of path planning for osteochondral integrated scaffolds with gradient structure is put forward, which provides a theoretical basis for bone-scaffold modeling and practical preparation. The implementation of the path planning processing system makes it possible to process data automatically from the initial stereo lithography(STL) model of the actual bone defect part by computer X-ray tomography technique(CT) scan or modeling,to generate the path code and to generate the final machining information after post-processing. This work provides some guidelines for independent research and development of automation equipment for biological manufacturing preparation and software *** experiment and test results have verified the validity of the path planning method and the good properties of the bone scaffolds with gradient structures.

关键词： 3D printing biological bone-scaffold path planning additive manufacturing tissue engineering.

Dynamics of Bt cotton Cry1Ac protein content under an alternating high temperature regime and effects on nitrogen metabolism

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Journal of Integrative Agriculture 2018年第9期17卷 1991-1998页

作者： ZHANG Xiang RUI Qiu-zhi LIANG Pan-pan wei chen-hua DENG Guo-qiang chen Yuan DONG Zhao-di chen De-hua Key Laboratory of Crop Genetics and Physiology of Jiangsu Province Yangzhou UniversityYangzhou 225009P.R.China Plant Genome Mapping Laboratory University of GeorgiaAthens 30605USA

This study was conducted to investigate the effects of alternating high temperature on CrylAc protein content on Bt cotton cultivars Sikang 1 （SK-1, a conventional cultivar） and Sikang 3 （SK-3, a hybrid cultivar）. In 2011 and 2012, cotton plants were subjected to high temperature treatments ranging from 32 to 40℃ in climate chambers to investigate the effects of high temperature on boll shell insecticidal protein expression. The experiments showed that significant decline of the boll shell insecticidal protein was detected at temperatures higher than 38℃ after 24 h. Based on the results, the cotton plants were treated with the threshold temperature of 38℃ from 6：00 a.m. to 6：00 p.m. followed by a normal temperature of 27℃ during the remaining night hours （DH/NN） in 2012 and 2013. These treatments were conducted at peak boll growth stage for both cultivars in study periods of 0, 4, 7, and 10 d. Temperature treatment of 32℃ from 6：00 a.m. to 6：00 p.m. and 27℃ in the remaining hours was set as control. The results showed that, compared with the control, after the DH/NN stress treatment applied for 7 d, the boll shell CrylAc protein content level was significantly decreased by 19.1 and 17.5% for SK-1 and by 15.3 and 13.7% for SK-3 in 2012 and 2013, respectively. Further analysis of nitrogen metabolic physiology under DH/NN showed that the soluble protein content and the glutamic pyruvic transaminase （GPT） activities decreased slightly after 4 d, and then decreased sharply after 7 d. The free amino acid content and the protease content increased sharply after 7 d. The changes in SK-1 were greater than those in SK-3. These results suggest that under DH/NN stress, boll shell CrylAc protein content decline was delayed. Reduced protein synthesis and increased protein degradation in the boll shell decreased protein content, including Bt protein, which may reduce resistance to the cotton bollworm.

关键词： Bt cotton alternating temperature CrylAc protein nitrogen metabolism

Effects of intra-gastric beta-casomorphin-7 on somatostatin and gastrin gene expression in rat gastric mucosa

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World Journal of Gastroenterology 2007年第14期13卷 2094-2099页

作者： Ya-Feng Zong wei-hua chen Yuan-Shu Zhang Si-Xiang Zou Department of Animal Physiology and Biochemistry Nanjing Agricultural University Nanjing 210095 Jiangshu Province China

AIM： To investigate the in vivo effect of beta-casomorphin-7on the regulation of gastric somatostatin and gastrin messenger RNA in rat gastric mucosa.METHODS： Somatostatin and gastrin mRNA were quantified by RT-PCR and in situ hybridization （ISH）in 24 rats. The rats were divided into three treatment groups： basal diet ＋ physiological saline （n = 8）, basal diet ＋ beta-casomorphin-7 （7.5 × 10^-7 mol）（n = 8）,and basal diet ＋ poly-Gly-7 （containing equal mol of N with 7.5 × 10^-7 mol beta-casomorphin-7）（n = 8）.After oral administration for 30 days, rats were killed by exsanguinations.RESULTS： After intra-gastric administration of betacasomorphin-7 for 30 d, gastrin mRNA increased by 52.8% （P 〈 0.05, n = 8）, and somatostatin mRNA levels decreased by 30.7% compared with the controls （P 〈0.01, n = 8）. No significant differences in the expression of the two genes were observed in the poly-Gly-treated group, although gastrin mRNA expression was elevated by 35.6% as against the control group （P = 0.15, n =8）. The long-term oral administration of a casomorphin solution significantly decreased the even gray of D-cells,but did not lower the number of D-cells both in the antrum and fundus. Interestingly, the number of G-cells increased in the antrum and fundus, but its average density was augmented only in the antrum.CONCLUSION： Beta-casomorphin-7 is capable of modulating gene expression of the regulatory peptides from G and D cells. Data from in situ hybridization studies indicate that beta-casomorphin-7 affects gastrin gene expression indirectly by means of the paracrine action of somatostatin, and depends on its intrinsic molecular function.

关键词： Beta-casomorphin-7 Adult rat Somatostatin Gastrin Expression

Consistent Alterations of Human Fecal Microbes After Transplantation into Germ-free Mice

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Genomics, Proteomics & Bioinformatics 2022年第2期20卷 382-393页

作者： Yanze Li Wenming Cao Na L Gao Xing-Ming Zhao wei-hua chen MOE Key Laboratory of Molecular Biophysics Hubei Key Laboratory of Bioinformatics and Molecular-imagingDepartment of Bioinformatics and Systems BiologyCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Institute of Science and Technology for Brain-Inspired Intelligence(ISTBI) Fudan UniversityShanghai 200433China College of Life Science Henan Normal UniversityXinxiang 453007China

Fecal microbiota transplantation(FMT)of human fecal samples into germ-free(GF)mice is useful for establishing causal relationships between the gut microbiota and human ***,due to the intrinsic differences between human and mouse intestines and the different diets of the two organisms,it may not be possible to replicate human phenotypes in mice through FMT;similarly,treatments that are effective in mouse models may not be effective in *** this study,we aimed to identify human gut microbes that undergo significant and consistent changes(i.e.,in relative abundances)after transplantation into GF mice in multiple experimental *** collected 16S rDNA-seq data from four published studies and analyzed the gut microbiota profiles from 1713 human–mouse ***,on average,we found that only 47%of the human gut microbes could be re-established in mice at the species level,among which more than 1/3 underwent significant changes(referred to as“variable taxa”).Most of the human gut microbes that underwent significant changes were consistent across multiple human–mouse pairs and experimental ***,about 1/3 of human samples changed their enterotypes,i.e.,significant changes in their leading species after *** fed with a controlled diet showed a lower enterotype change rate(23.5%)than those fed with a noncontrolled diet(49.0%),suggesting a possible solution for *** of the variable taxa have been reported to be implicated in human diseases,with some recognized as the causative *** results highlight the challenges of using a mouse model to replicate human gut microbiota-associated phenotypes,provide useful information for researchers using mice in gut microbiota studies,and call for additional validations after *** online database named FMT-DB is publicly available at http://***/#/.

关键词： Germ-free mice Fecal microbiota transplantation Gut microbe Enterotype 16S rDNA

Selection for Cheaper Amino Acids Drives Nucleotide Usage at the Start of Translation in Eukaryotic Genes

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Genomics, Proteomics & Bioinformatics 2021年第6期19卷 949-957页

作者： Na L.Gao Zilong He Qianhui Zhu Puzi Jiang Songnian Hu wei-hua chen Key Laboratory of Molecular Biophysics of the Ministry of Education Hubei Key Laboratory of Bioinformatics and Molecular-imagingDepartment of Bioinformatics and Systems BiologyCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Institute for Computer Science and Cluster of Excellence on Plant Sciences Heinrich Heine UniversityD-40225 DuesseldorfGermany CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Interdisciplinary Innovation Institute of Medicine and EngineeringBeihang UniversityBeijing 100191China University of Chinese Academy of Sciences Beijing 100049China

Coding regions have complex interactions among multiple selective forces,which are manifested as biases in nucleotide *** studies have revealed a decreasing GC gradient from the 5′-end to 3′-end of coding regions in various *** confirmed that this gradient is universal in eukaryotic genes,but the decrease only starts from the~25th *** trend is mostly found in nonsynonymous(ns)sites at which the GC gradient is universal across the eukaryotic *** GC contents at ns sites result in cheaper amino acids,indicating a universal selection for energy efficiency toward the N-termini of encoded *** a genome,the decreasing GC gradient is intensified from lowly to highly expressed genes(more and more protein products),further supporting this *** reveals a conserved selective constraint for cheaper amino acids at the translation start that drives the increased GC contents at ns *** GC contents can facilitate transcription but result in a more stable local secondary structure around the start codon and subsequently impede translation ***,the GC gradients at four-fold and two-fold synonymous sites vary across *** could decrease or increase,suggesting different constraints acting at the GC contents of different codon sites in different *** study reveals that the overall GC contents at the translation start are consequences of complex interactions among several major biological processes that shape the nucleotide sequences,especially efficient energy usage.

关键词： Macroevolution Prioritization of selective forces Energy efficiency Transcription Translation initiation

A 2.5-dimensional Analytical Model of Cold Leveling for Plates with Transverse Wave Defects

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Journal of Iron and Steel Research International 2015年第8期22卷 664-671页

作者： wei-hua chen Juan LIU Zhen-shan CUI Ying-jie WANG Ying-rui WANG National Die & Mold CAD Engineering Research Center Shanghai Jiaotong University Baosteel Co. Ltd.

Waves occurring in cold-rolled plates or sheets can be divided into longitudinal and transverse waves. Classical leveling theories merely solve the problem of longitudinal waves, while no well accepted method can be employed for transverse waves. In order to investigate the essential deformation law of leveling for plates with transverse waves, a 2.5-dimensional （2.5- D） analytical approach was proposed. In this model, the plate was transversely divided into some strips with equal width; the strips are considered to be in the state of plane strain and each group of adjacent strips are assumed to be deformation compatible under stress. After calculation, the bending deformation of each strip and the leveling effect of overall plate were obtained by comprehensNe consideration of various strips along with the width. Bending of roller is a main approach to eliminate the transverse waves, which is widely accepted by the industry, but the essential effect of bending of roller on the deformation of plates and the calculation of bending of roller are unknown. According to the 2.5-D analytical model, it can be found that, for plates, it is neutral plane offsetting and middle plane elongation or contraction under inner stress that can effectively improve plate shape. Taking double side waves as an example, the appropriate values of bending of roller were obtained by the 2.5-D analytical model related to different initial unevenness, which was applicable to the current on-line adjusting of bending of roller in rolling industry.

关键词： plate leveling 2.5-dimensional analytical model transverse wave middle plane deformation

Fabrication of hierarchical polycaprolactone/gel scaffolds via combined 3D bioprinting and electrospinning for tissue engineering

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Advances in Manufacturing 2014年第3期2卷 231-238页

作者： Yong-Ze Yu Lu-Lu Zheng Hai-Ping chen wei-hua chen Qing-Xi Hu Rapid Manufacturing Engineering Center Shanghai University

It is a severe challenge to construct 3D scaf- folds which hold controllable pore structure and similar morphology of the natural extracellular matrix （ECM）. In this study, a compound technology is proposed by com- bining the 3D bioprinting and electrospinning process to fabricate 3D scaffolds, which are composed by orthogonal array gel microfibers in a grid-like arrangement and inter- calated by a nonwoven structure with randomly distributed polycaprolactone （PCL） nanofibers. Human adipose- derived stem cells （hASCs） are seeded on the hierarchical scaffold and cultured 21 d for in vitro study. The results of cells culturing show that the microfibers structure with controlled pores can allow the easy entrance of cells and the efficient diffusion of nutrients, and the nanofiber webs layered in the scaffold can significantly improve initial cell attachment and proliferation. The present work demon- strates that the hierarchical PCL/gel scaffolds consisting of controllable 3D architecture with interconnected pores and biomimetic nanofiber structures resembling the ECM can be designed and fabricated by the combination of 3D bioprinting and electrospinning to improve biological per- formance in tissue engineering applications.

关键词： Hierarchical scaffold 3D bioprinting Electrospinning Tissue engineering