81 results on '"Bao, Shi"'
Search Results
2. Spatial Variations and Potential Risks of Heavy Metals in Seawater, Sediments, and Living Organisms in Jiuzhen Bay, China
- Author
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Xia Sun, Bao-Shi Li, Xuan-Li Liu, and Cheng-Xuan Li
- Subjects
Chemistry ,QD1-999 - Abstract
Coastal waters are polluted by heavy metals to varying degrees, posing potential risks to marine ecology and human health. In May 2006, the pollution levels, sources, and ecological risks of heavy metals (Cu, Pb, Zn, Cd, Hg, and As) in seawater, surface sediments, and living organisms were studied in Jiuzhen Bay in Fujian, China. This study identified Hg (0.26–0.72 µg/L) and As (20.3–31.5 µg/L) pollution in the seawater of Jiuzhen Bay. In sediments, heavy Pb pollution (946 µg/g dw) was only detected at one station at a level posing very serious potential risk, while Hg pollution (0.052–0.087 µg/g dw) was observed at three stations at a level posing serious potential risk. No heavy metal pollution was detected in sediments at other stations. The concentrations of five heavy metals (Cu, Zn, As, Cd, and Pb) exceeded the corresponding National Quality Standards for oysters, indicating heavy pollution, based on an ecological risk assessment. In clams, two heavy metals (Pb and As) exceeded the standards, indicating light pollution, based on an ecological risk assessment. No heavy metal pollution was found in fish or shrimps. The heavy metals in the seawater and sediments of Jiuzhen Bay are mainly derived from the river discharges of Luxi and Wujiang Rivers although sewage discharge along the coast of Jiuzhen Bay is another source of heavy metal pollution at some stations. Given the pollution of Pb, Hg, and As in seawater and sediments at some stations within the bay, the potential risks of Pb, Hg, and As in living organisms to both the marine ecology and human health deserve increased attention.
- Published
- 2020
- Full Text
- View/download PDF
3. Molecular Characterization of Three Gonadotropin Subunits and Their Expression Patterns during Ovarian Maturation in Cynoglossus semilaevis
- Author
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Bao Shi, Xuezhou Liu, Yongjiang Xu, and Shanshan Wang
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Cynoglossus semilaevis ,multiple spawner ,gonadotropin ,cDNA cloning ,expression patterns ,oocyte maturation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The endocrine regulation of reproduction in a multiple spawning flatfish with an ovary of asynchronous development remains largely unknown. The objectives of this study were to monitor changes in mRNA expression patterns of three gonadotropin hormone (GTH) subunits (FSHβ, LHβ and CGα) and plasma GTH levels during ovarian maturation of half-smooth tongue sole Cynoglossus semilaevis. Cloning and sequence analysis revealed that the cDNAs of FSHβ, LHβ and CGα were 541, 670 and 685 bp in length, and encode for peptides of 130, 158 and 127 amino acids, respectively. The number of cysteine residues and potential N-linked glycosylation sites of the flatfish GTHs were conserved among teleosts. However, the primary structure of GTHs in Pleuronectiformes appeared to be highly divergent. The FSHβ transcriptional level in the pituitary remained high during the vitellogenic stage while plasma levels of FSH peaked and oocyte development was stimulated. The LHβ expression in the pituitary and ovary reached the maximum level during oocyte maturation stages when the plasma levels of LH peaked. The brain GTHs were expressed at the different ovarian stages. These results suggested that FSH and LH may simultaneously regulate ovarian development and maturation through the brain-pituitary-ovary axis endocrine system in tongue sole.
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- 2015
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4. Symmetric cytotoxic trimeric and dimeric indole alkaloids isolated from Bousigonia angustifolia
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Xiang-Hai Cai, Bao-Bao Shi, Jing-Song Lu, Mei-Fen Bao, and Jing Wu
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Indole test ,Indole alkaloid ,010405 organic chemistry ,Chemistry ,Stereochemistry ,Organic Chemistry ,Tumor cells ,Trimer ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,0104 chemical sciences ,Cytotoxic T cell ,Bousigonia angustifolia ,Cytotoxicity - Abstract
A symmetric monoterpenoid indole alkaloid trimer, bousangustine A, is reported for the first time, as well as the dimeric alkaloids bousangustines B and C; these were isolated from the trunks of Bousigonia angustifolia. The structures, which feature a symmetric 6/9/5/6 ring system, were elucidated using comprehensive spectroscopic analysis. Their absolute configurations were determined via X-ray crystal diffraction, as well as computational chemistry. They can be constructed through Friedel–Crafts and free radical reactions, respectively. These compounds exhibited significant cytotoxicity against tumor cells.
- Published
- 2021
5. Comprehension of the α-Arylation of Nitroalkanes
- Author
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Zuo-Yi Jiao, Fu-Min Zhang, Yang An, Peng-Fei Zheng, and Zhou-Bao Shi
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Comprehension ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Organic chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences - Abstract
Background: α-Aryl substituted nitroalkanes are important synthetic intermediates for the preparation of pharmaceutical molecules, natural products, and functional materials. Due to their scare existence in Nature, synthesis of these compounds has attracted the attention of synthetic and medicinal chemists, rendering α-arylation of nitroalkanes of an important research topic. This article summarizes the important advances of α- arylation of nitroalkanes since 1963. Results: After a brief introduction of the synthetic application and the reactions of nitroalkanes, this article reviewed the synthetic methods for the α-arylated aliphatic nitro compound. The amount of research on α-arylation of nitroalkanes using various arylation reagents and the discovery of elegant synthetic approaches towards such skeleton have been discussed. This review described these advances in two sections. One is the arylation of non-activated nitroalkanes, with an emphasis on the application of diverse arylation reagents; the other focuses on the arylation of activated nitroalkanes, including dinitroalkanes, trinitroalkanes, α-nitrosulfones, α-nitroesters, α-nitrotoluenes, and α-nitroketones. The synthetic application of these methods has also been presented in some cases. Conclusion: In this review, we described the progress of α-arylation of nitroalkanes. Although the immense amount of research on α-arylation of aliphatic nitro compounds has been achieved, many potential issues still need to be addressed, especially the asymmetric transformation and its wide application in organic synthesis.
- Published
- 2019
6. Investigating the electromagnetic wave-absorbing capacity and mechanical properties of flexible radar-absorbing knitted compound materials
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Li Xianghong, Chen Niuniu, Tianhang Zhan, Sainan Wei, Ruosi Yan, and Bao Shi
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010302 applied physics ,Materials science ,Polymers and Plastics ,Materials Science (miscellaneous) ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Electromagnetic radiation ,Industrial and Manufacturing Engineering ,law.invention ,Nickel ,chemistry ,Ferromagnetism ,law ,0103 physical sciences ,Chemical Engineering (miscellaneous) ,Fiber ,Radar ,Composite material ,0210 nano-technology - Abstract
This study fabricated flexible radar-absorbing knitted compound materials by weft knitting and blending ferromagnetic nickel micron-fibers and cotton fiber into structures with a concave–convex surface, including rhombic, mat, wavy, and leno stitches. The electromagnetic wave-absorbing capability and mechanical properties of the flexible radar-absorbing knitted compound materials were evaluated. The results showed that the rhombic, mat, and wavy stitches displayed high mechanical properties with high bursting strength and there were no significant differences among them. The rhombic stitch flexible radar-absorbing knitted compound material with a ferromagnetic nickel micron-fiber content of 14% had a maximum bandwidth of 13 GHz and achieved a minimum reflectance of −20 dB at 7 GHz, which was 150% that of mat fabric, and 200% that of wavy fabric and leno fabric. This was ascribed to the fact that the concave–convex surface with regular diamond-shaped block improved the dispersion of the electromagnetic wave, weakened the wave strength, and increased the interference. Therefore, the rhombic stitch flexible radar-absorbing knitted compound material was the most suitable for flexible radar-absorbing material in this study. The development of flexible radar-absorbing materials, by combining aerospace technology, military technology and textile technology, is important for the application in stealth of aircraft and weapons.
- Published
- 2019
7. Four Yellow Monoterpenoid Quinoline Alkaloids from the Stem of Tabernaemontana bovina
- Author
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Bao-Bao Shi, Yi Wang, Yang Yu, Mei-Fen Bao, Jing Wu, Xiang-Hai Cai, and Johann Schinnerl
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Lipopolysaccharides ,Models, Molecular ,Tabernaemontana ,Stereochemistry ,Nitric oxide biosynthesis ,Crystallography, X-Ray ,Nitric Oxide ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Mice ,chemistry.chemical_compound ,Alkaloids ,Animals ,Physical and Theoretical Chemistry ,Molecular Structure ,biology ,010405 organic chemistry ,Chemistry ,Macrophages ,Alkaloid ,Organic Chemistry ,Quinoline ,biology.organism_classification ,0104 chemical sciences ,RAW 264.7 Cells ,Quinolines - Abstract
Four unprecedented yellow alkaloids named as taberbovines A-D (1-4) were isolated from stems of Tabernaemontana bovina Lour. Their structures were elucidated by the comprehensive spectroscopic data, computational chemistry, and X-ray crystal diffraction. Alkaloids 1-4 possessed a unique 6/6/5/6/5 ring system and were assigned to monoterpenoid quinolines. Biosynthetically, the isolated alkaloids may be derived from Aspidosperma-type alkaloid by oxidation and rearrangements. Taberbovines A-D exhibited the good inhibitory activities of formation NO in LPS induced RAW264.7 macrophages.
- Published
- 2019
8. MicroRNA-210-3p Promotes Chondrogenic Differentiation and Inhibits Adipogenic Differentiation Correlated with HIF-3α Signalling in Bone Marrow Mesenchymal Stem Cells
- Author
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You-Rong Chen, Xin Yan, Bao-Shi Fan, Fu-Zhen Yuan, Ming-Ze Du, Bing-Bing Xu, Yi-Fan Song, Jing Ye, Jia-Kuo Yu, Meng Yang, and Zi-Mu Mao
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Male ,Article Subject ,SOX9 ,Models, Biological ,General Biochemistry, Genetics and Molecular Biology ,Rats, Sprague-Dawley ,microRNA ,medicine ,Animals ,RNA, Messenger ,Adipogenesis ,Binding Sites ,General Immunology and Microbiology ,Base Sequence ,Chemistry ,Cartilage ,Regeneration (biology) ,Mesenchymal stem cell ,Mesenchymal Stem Cells ,General Medicine ,Chondrogenesis ,Cell biology ,MicroRNAs ,medicine.anatomical_structure ,Medicine ,Signal transduction ,Research Article ,Signal Transduction ,Transcription Factors - Abstract
Cartilage injury of the knee joint is very common. Due to the limited self-healing ability of articular cartilage, osteoarthritis is very likely to occur if left untreated. Bone marrow mesenchymal stem cells (BMMSCs) are widely used in the study of cartilage injury due to their low immunity and good amplification ability, but they still have disadvantages, such as heterogeneous undifferentiated cells. MicroRNAs can regulate the chondrogenic differentiation ability of MSCs by inhibiting or promoting mRNA translation and degradation. In this research, we primarily investigated the effect of microRNA-210-3p (miR-210-3p) on chondrogenic and adipogenic differentiation of BMMSCs in vitro. Our results demonstrate that miR-210-3p promoted chondrogenic differentiation and inhibited adipogenic differentiation of rat BMMSCs, which was related to the HIF-3α signalling pathway. Additionally, miR-210-3p promotes mRNA and protein levels of the chondrogenic expression genes COLII and SOX9 and inhibits mRNA and protein levels of the adipogenic expression genes PPARγ and LPL. Thus, miR-210-3p combined with BMMSCs is a candidate for future clinical applications in cartilage regeneration and could represent a promising new therapeutic target for OA.
- Published
- 2021
9. Advances of Stem Cell-Laden Hydrogels With Biomimetic Microenvironment for Osteochondral Repair
- Author
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Bingbing Xu, Jing Ye, Fu-Zhen Yuan, Ji-Ying Zhang, You-Rong Chen, Bao-Shi Fan, Dong Jiang, Wen-Bo Jiang, Xing Wang, and Jia-Kuo Yu
- Subjects
0301 basic medicine ,Histology ,lcsh:Biotechnology ,extracellular matrix ,osteochondral tissue engineering ,Biomedical Engineering ,regenerative medicine ,Bioengineering ,02 engineering and technology ,Review ,Regenerative medicine ,Extracellular matrix ,Cell therapy ,03 medical and health sciences ,Joint disease ,stem cell-laden hydrogels ,lcsh:TP248.13-248.65 ,Cell adhesion ,Chemistry ,Regeneration (biology) ,Bioengineering and Biotechnology ,021001 nanoscience & nanotechnology ,microenvironment ,Cell biology ,030104 developmental biology ,Self-healing hydrogels ,Stem cell ,0210 nano-technology ,Biotechnology - Abstract
Osteochondral damage from trauma or osteoarthritis is a general joint disease that can lead to an increased social and economic burden in the modern society. The inefficiency of osteochondral defects is mainly due to the absence of suitable tissue-engineered substrates promoting tissue regeneration and replacing damaged areas. The hydrogels are becoming a promising kind of biomaterials for tissue regeneration. The biomimetic hydrogel microenvironment can be tightly controlled by modulating a number of biophysical and biochemical properties, including matrix mechanics, degradation, microstructure, cell adhesion, and intercellular interactions. In particular, advances in stem cell-laden hydrogels have offered new ideas for the cell therapy and osteochondral repair. Herein, the aim of this review is to underpin the importance of stem cell-laden hydrogels on promoting the development of osteochondral regeneration, especially in the field of manipulation of biomimetic microenvironment and utilization growth factors with various delivery methods.
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- 2020
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10. Spatial Variations and Potential Risks of Heavy Metals in Seawater, Sediments, and Living Organisms in Jiuzhen Bay, China
- Author
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Xuan-Li Liu, Xia Sun, Cheng-Xuan Li, and Bao-Shi Li
- Subjects
Pollution ,010504 meteorology & atmospheric sciences ,Article Subject ,Potential risk ,Chemistry ,Pb pollution ,media_common.quotation_subject ,Light pollution ,Heavy metals ,General Chemistry ,010501 environmental sciences ,01 natural sciences ,Human health ,Environmental chemistry ,Seawater ,Bay ,QD1-999 ,0105 earth and related environmental sciences ,media_common - Abstract
Coastal waters are polluted by heavy metals to varying degrees, posing potential risks to marine ecology and human health. In May 2006, the pollution levels, sources, and ecological risks of heavy metals (Cu, Pb, Zn, Cd, Hg, and As) in seawater, surface sediments, and living organisms were studied in Jiuzhen Bay in Fujian, China. This study identified Hg (0.26–0.72 µg/L) and As (20.3–31.5 µg/L) pollution in the seawater of Jiuzhen Bay. In sediments, heavy Pb pollution (946 µg/g dw) was only detected at one station at a level posing very serious potential risk, while Hg pollution (0.052–0.087 µg/g dw) was observed at three stations at a level posing serious potential risk. No heavy metal pollution was detected in sediments at other stations. The concentrations of five heavy metals (Cu, Zn, As, Cd, and Pb) exceeded the corresponding National Quality Standards for oysters, indicating heavy pollution, based on an ecological risk assessment. In clams, two heavy metals (Pb and As) exceeded the standards, indicating light pollution, based on an ecological risk assessment. No heavy metal pollution was found in fish or shrimps. The heavy metals in the seawater and sediments of Jiuzhen Bay are mainly derived from the river discharges of Luxi and Wujiang Rivers although sewage discharge along the coast of Jiuzhen Bay is another source of heavy metal pollution at some stations. Given the pollution of Pb, Hg, and As in seawater and sediments at some stations within the bay, the potential risks of Pb, Hg, and As in living organisms to both the marine ecology and human health deserve increased attention.
- Published
- 2020
- Full Text
- View/download PDF
11. Molecular characterization and expression profiles of insulin-like growth factors in yellowtail kingfish (Seriola lalandi) during embryonic development
- Author
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Yaxing Zhang, Bao Shi, Quan Liu, Xuezhou Liu, Yongjiang Xu, Bin Wang, and Yongshan Liu
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Signal peptide ,endocrine system ,Embryo, Nonmammalian ,animal structures ,Physiology ,medicine.medical_treatment ,Embryonic Development ,Aquatic Science ,Biology ,Biochemistry ,03 medical and health sciences ,Insulin-like growth factor ,food ,Somatomedins ,Complementary DNA ,Gene expression ,medicine ,Animals ,Amino Acid Sequence ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Seriola lalandi ,Base Sequence ,Embryogenesis ,Fishes ,Gene Expression Regulation, Developmental ,04 agricultural and veterinary sciences ,General Medicine ,Molecular biology ,food.food ,Amino acid ,Open reading frame ,chemistry ,040102 fisheries ,0401 agriculture, forestry, and fisheries - Abstract
In this study, to understand the role of the insulin-like growth factor (IGF) system in the regulation of early development in yellowtail kingfish (YTK, Seriola lalandi), an economically important marine fish species with a high potential for aquaculture, we first cloned the full-length cDNAs for igf1 and igf2 from the liver. YTK igf1 cDNA was 1946 base pairs (bp) in length with an open reading frame (ORF) of 558 bp encoding preproIGF1 of 185 amino acids (aa). The preproIGF1 consisted of 44 aa for the signal peptide, 68 aa for the mature peptide comprising B, C, A, and D domains, and 73 aa for the E domain. YTK igf2 cDNA had an ORF of 648 bp that encoded a total of 215 aa spanning the signal peptide (47 aa), the mature peptide (70 aa), and the E domain (98 aa). At the protein level, both YTK IGF1 and IGF2 exhibited high sequence identities with their corresponding fish counterparts, respectively. Subsequently, quantitative RT-PCR analysis indicated that the highest level of igf1 mRNA expression was recorded in the gonad and liver, while the igf2 mRNA expression was most abundant in the gill and liver. In addition, both igf1 and igf2 were detected in all stages of embryonic development and exhibited different gene expression patterns, supporting that IGF1 and IGF2 could be functional and play important roles during YTK embryogenesis. Overall, this initial study of IGF1 and IGF2 provides an insight into the endocrine mechanism involved in the early development of yellowtail kingfish.
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- 2018
12. Three New Indole Alkaloids from Tabernaemontana divaricata
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Xiang-Hai Cai, Jing Wu, Mei-Fen Bao, Yan Deng, and Bao-Bao Shi
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3α-hydroxymethyl-ibogamine ,Monoterpene ,Tabernaemontana divaricata ,Plant Science ,Toxicology ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,HeLa ,3α-acetatemethoxyl-ibogamine ,lcsh:Botany ,medicine ,Bioorganic chemistry ,16α-hydroxyl-ibogamine ,heterocyclic compounds ,Cytotoxicity ,Pharmacology ,Indole test ,Traditional medicine ,biology ,Apocynaceae ,010405 organic chemistry ,Chemistry ,organic chemicals ,Organic Chemistry ,Monoterpene indole alkaloids ,Cancer ,medicine.disease ,biology.organism_classification ,lcsh:QK1-989 ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Original Article ,Food Science - Abstract
Three new monoterpene indole alkaloids, 3α-hydroxymethyl-ibogamine (1), 3α-acetatemethoxyl-ibogamine (2), 16α-hydroxyl-ibogamine (3) together with six known alkaloids were isolated from the branches and leaves of Tabernaemontana divaricata (Apocynaceae). The structures of these alkaloids were determined by spectroscopic analyses. All isolated compounds showed no significant cytotoxicity against SGC-7901 gastric cancer, HeLa, and A-549 lung cancer cell lines (IC50 > 20 µM). Graphical Abstract Electronic supplementary material The online version of this article (10.1007/s13659-018-0166-x) contains supplementary material, which is available to authorized users.
- Published
- 2018
13. Impaired CBS-H2S signaling axis contributes to MPTP-induced neurodegeneration in a mouse model of Parkinson’s disease
- Author
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Bao-Shi Yuan, Jin-Song Bian, Yu-Qing Yuan, Li-Fang Hu, Xin Yuan, Ya-Li Wang, Chun-Feng Liu, and Xiao-Ou Hou
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0301 basic medicine ,Endocrine and Autonomic Systems ,Chemistry ,MPTP ,Immunology ,Neurodegeneration ,Dopaminergic ,Neurotoxicity ,Striatum ,medicine.disease ,Neuroprotection ,Cell biology ,03 medical and health sciences ,Behavioral Neuroscience ,chemistry.chemical_compound ,030104 developmental biology ,nervous system ,Dopaminergic Cell ,medicine ,Neuroscience ,Neuroinflammation - Abstract
Hydrogen sulfide (H2S), a novel neuromodulator, is linked to the pathogenesis of several neurodegenerative disorders. Exogenous application of H2S exerts neuroprotection via anti-inflammation and anti-oxidative stress in animal and cellular models of Parkinson's disease (PD). However, the role of endogenous H2S and the contribution of its various synthases in PD remain unclear. In the present study, we found a decline of plasma and striatal sulfide level in 1-methy-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced PD mouse model. Interestingly, among the three H2S generating enzymes, only cystathionine β-synthase (CBS) expression was largely reduced in the striatum of MPTP-treated mice. The in vitro study confirmed a significant decrease of CBS expression in 1-methyl-4-phenylpyridinium (MPP+)-stimulated astrocytes and microglia, but not in neurons or SH-SY5Y dopaminergic cells. Striatal CBS overexpression, elicited by stereotaxic delivery with Cbs gene using recombinant adeno-associated-virus (rAAV-Cbs), successfully enhanced the sulfide level in the striatum and partially rescued the MPTP-induced dopaminergic neurotoxicity in the midbrain. Specifically, striatal CBS overexpression alleviated the motor deficits and dopaminergic neuron losses in the nigro-striatal pathway, with a concomitant inhibition of glial activation in MPTP-treated mice. Furthermore, compared to rAAV-Vector, rAAV-Cbs injection reduced the aberrant accumulation of nitric oxide and 3-nitrotyrosine (an indicator of protein nitration) in the striatum of MPTP-treated mice. Notably, it also attenuated the increase of nitrated α-synuclein level in MPTP mice. The in vitro study demonstrated that lentivirus-mediated CBS overexpression elevated the sulfide generation in glial cells. Moreover, glial CBS overexpression offered protection to midbrain dopaminergic neurons through repressing nitric oxide overproduction in both glial and neuronal cells induced by MPP+. Taken together, our data suggest that impaired CBS-H2S axis may contribute to the pathogenesis of PD, and that modulation of this axis may become a novel therapeutic approach for PD.
- Published
- 2018
14. Aceclofenac-Hydroxypropyl-β-Cyclodextrin Complex for Prolonged and Improved Drug Delivery for Orthopedic Applications
- Author
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Zhang Licheng, Pei-Fu Tang, Zhang Wei, Hao Zhang, Long-Bao Shi, and Zhao Yanpeng
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Chemistry ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,02 engineering and technology ,Pharmacology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Drug delivery ,medicine ,Aceclofenac ,0210 nano-technology ,Hydroxypropyl β cyclodextrin ,Biotechnology ,medicine.drug - Published
- 2017
15. Metabolic engineering of Escherichia coli W3110 for the production of <scp>l</scp>-methionine
- Author
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Zhong Yang Ding, Zheng Hua Gu, Hua Li, Bao Shi Wang, You Ran Li, Gui Yang Shi, and Liang Zhang
- Subjects
Threonine ,0301 basic medicine ,Bioengineering ,medicine.disease_cause ,Applied Microbiology and Biotechnology ,law.invention ,Metabolic engineering ,Industrial Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,Methionine ,law ,Escherichia coli ,medicine ,Derepression ,DNA Primers ,Escherichia coli Proteins ,Methylation ,Carbon ,Recombinant Proteins ,030104 developmental biology ,Regulon ,Metabolic Engineering ,chemistry ,Biochemistry ,Fermentation ,Mutagenesis, Site-Directed ,Recombinant DNA ,Plasmids ,Biotechnology - Abstract
In this study, we constructed an l-methionine-producing recombinant strain from wild-type Escherichia coli W3110 by metabolic engineering. To enhance the carbon flux to methionine and derepression met regulon, thrBC, lysA, and metJ were deleted in turn. Methionine biosynthesis obstacles were overcome by overexpression of metAFbr (Fbr, Feedback resistance), metB, and malY under control of promoter pN25. Recombinant strain growth and methionine production were further improved by attenuation of metK gene expression through replacing native promoter by metK84p. Blocking the threonine pathway by deletion of thrBC or thrC was compared. Deletion of thrC showed faster growth rate and higher methionine production. Finally, metE, metF, and metH were overexpressed to enhance methylation efficiency. Compared with the original strain E. coli W3110, the finally obtained Me05 (pETMAFbr-B-Y/pKKmetH) improved methionine production from 0 to 0.65 and 5.62 g/L in a flask and a 15-L fermenter, respectively.
- Published
- 2017
16. Naringenin inhibits spinal cord injury-induced activation of neutrophils through miR-223
- Author
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Peifu Tang, Long-Bao Shi, Wei Zhang, Licheng Zhang, Hao Zhang, and Zhao Yanpeng
- Subjects
Male ,0301 basic medicine ,Naringenin ,medicine.medical_specialty ,Neutrophils ,medicine.medical_treatment ,Interleukin-1beta ,Anti-Inflammatory Agents ,Biology ,Neutrophil Activation ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Injury Site ,mir-223 ,Internal medicine ,NLR Family, Pyrin Domain-Containing 3 Protein ,Genetics ,medicine ,Animals ,Spinal cord injury ,Saline ,Spinal Cord Injuries ,Neuroinflammation ,Laminectomy ,General Medicine ,medicine.disease ,Spinal cord ,Rats ,MicroRNAs ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Flavanones ,Immunology ,030217 neurology & neurosurgery - Abstract
Naringenin (NR), a flavonoid abundant in citrus fruits has been reported to possess anti-inflammatory properties. The present study aimed to investigate the protective of naringenin in rats after spinal cord injury (SCI) and the underlying mechanisms associated with neuroinflammation. Adult male Sprague-Dawley rats were subjected to laminectomy at T9-T11 and compression with a vascular clip. The spinal cords spanning the injury site about 0.8cm were collected for testing. There were five groups (n=7 in each group): (a) Control group; (b) sham group group; (c) SCI+saline; (d) SCI+NR (50mg/kg, p.o.) group and (e) SCI+NR (100mg/kg, p.o.) group. Different doses of NR (50mg/kg, p.o. and 100mg/kg, p.o.) or saline were administered once daily for 11 consecutive days, from 3days prior to surgery to 7days after surgery. The expression level of miR-223, NLRP3 and IL-1β were measured by RT- qPCR. The accumulation of neutrophils at the site of compression, as evaluated by measuring the tissue myeloperoxidase activity, significantly increased with time following the compression, peaking at 24h post compression. The expression of miR-223 was significant elevated in (b). However, spinal cord myeloperoxidase activity and the expression of miR-223 did not increase in sham-operated animals. NR significantly inhibited a SCI-induced activation of neutrophils through repressed miR-223 in group (d) and (e). There was a better effect in group (e) than group (d). miR-223 is thought to act as a fine-tuner of granulocyte production and the inflammatory response. Our findings suggested that repeated administration of naringenin (100mg/kg, p.o) may provide the protective effect of the spinal cord injury in rats, possibly through inhibiting neuroinflammation.
- Published
- 2016
17. Novel Pyrazolo[4,3- d]pyrimidine as Potent and Orally Active Inducible Nitric Oxide Synthase (iNOS) Dimerization Inhibitor with Efficacy in Rheumatoid Arthritis Mouse Model
- Author
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Ming Ming Liu, Xin Huang, Xin Hua Liu, Liu Zeng Chen, Ming Ming Jiao, Wen Jian Tang, Bao Shi Wang, and Jing Bo Shi
- Subjects
Lipopolysaccharides ,Pyrimidine ,Pyridines ,Interleukin-1beta ,Anti-Inflammatory Agents ,Molecular Conformation ,Arthritis ,Nitric Oxide Synthase Type II ,Pharmacology ,Inhibitory postsynaptic potential ,Crystallography, X-Ray ,Nitric Oxide ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,Structure-Activity Relationship ,Drug Discovery ,medicine ,Animals ,Enzyme Inhibitors ,IC50 ,030304 developmental biology ,0303 health sciences ,Low toxicity ,biology ,Macrophages ,medicine.disease ,Arthritis, Experimental ,0104 chemical sciences ,Rats ,Nitric oxide synthase ,010404 medicinal & biomolecular chemistry ,Disease Models, Animal ,Orally active ,RAW 264.7 Cells ,chemistry ,Rheumatoid arthritis ,Drug Design ,biology.protein ,Molecular Medicine ,Pyrazoles ,Dimerization - Abstract
In order to discover novel anti-inflammatory agents for treatment of arthritis and based on preliminary structure–activity relationships, four series (A–D) of total 90 new pyrazolo[4,3-d]pyrimidine compounds were designed and synthesized. All the compounds have been tested for their anti-inflammatory activities by inhibiting of LPS-induced NO production. A clear structure–activity relationship has been concluded step by step, and finally 3,4,5-trimethoxystyryl-1H-pyrazolo[4,3-d]pyrimidine was found to be the most active scaffold. Among them, compound D27 was discovered as the most potent anti-inflammatory agent (IC50 = 3.17 μM) with low toxicity and strong inhibitory of NO release (IR = 90.4% at 10 μM). This compound also showed potent inhibition of iNOS with IC50 value of 1.12 μM. Preliminary mechanism studies indicated that it could interfere with the stability and formation of active dimeric iNOS. The anti-inflammatory effect of this compound was determined by adjuvant-induced arthritis in rat model. W...
- Published
- 2019
18. Design and synthesis of novel pyrazolo[4,3-d]pyrimidines as potential therapeutic agents for acute lung injury
- Author
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Jing Bo Shi, Ming Ming Liu, Xin Huang, Bao Shi Wang, and Liu Zeng Chen
- Subjects
Lipopolysaccharides ,Male ,pyrazolo[4,3-d]pyrimidine ,Pyrimidine ,synthesis ,Cell Survival ,Short Communication ,Pharmacology ,Lung injury ,Nitric Oxide ,Inhibitory postsynaptic potential ,Mice ,Structure-Activity Relationship ,chemistry.chemical_compound ,Drug Discovery ,Animals ,No production ,anti-inflammatory activity ,Cells, Cultured ,Dose-Response Relationship, Drug ,lcsh:RM1-950 ,General Medicine ,Mice, Inbred C57BL ,Pyrimidines ,RAW 264.7 Cells ,lcsh:Therapeutics. Pharmacology ,chemistry ,acute lung injury ,Drug Design ,Cytokines ,Pyrazoles ,lipids (amino acids, peptides, and proteins) ,Signal Transduction - Abstract
Four series of total 35 new pyrazolo[4,3-d]pyrimidine compounds were designed, synthesized and evaluated for their inhibitory activity against LPS-induced NO production in RAW264.7 macrophages. Among them, compound 4e was found to be the most potent inhibitor, which decreased the production of cytokines in vitro, such as NO, IL-6 and TNF-α, with IC50 values of 2.64, 4.38 and 5.63 μM, respectively. Further studies showed that compound 4e inhibited cytokines secretion of macrophages through suppressing TLR4/p38 signaling pathway. Additionally, compound 4e showed in vivo anti-inflammatory activity in LPS-induced model of acute lung injury. These data suggested that compound 4e may be a promising lead structure for the treatment of ALI.
- Published
- 2019
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19. Dimeric and monomeric dihydrostilbenes from the roots of Stemona mairei together with their hypoglycemic activities
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Ying Zeng, Bao-Bao Shi, Fang Wang, Xiang-Hai Cai, Gao Chen, and Johann Schinnerl
- Subjects
Quantum chemical ,Stemona mairei ,biology ,Chemistry ,Stereochemistry ,Chemical shift ,Organic Chemistry ,Absolute configuration ,biology.organism_classification ,Biochemistry ,chemistry.chemical_compound ,Monomer ,Phytochemical ,Drug Discovery ,Stemonaceae ,Plant species - Abstract
A carefully performed phytochemical investigation of the roots of Stemona mairei (Stemonaceae) led to the discovery of six so far undescribed dihydrostilbene dimers maistilbene A–F and four monomers maistilbene G–J. This is the first report of stilbenoids of this plant species and the first report of dimeric dihydrostilbenes from this plant family. The absolute configuration of these compounds was determined by a combination of Mo2(AcO)4-induced ECD spectra and quantum chemical calculation of NMR chemical shift, ECD and spin-spin coupling constants. Maistilbene G could increase the glucose consumption in L6 myotubes, disclosing a new hypoglycemic candidate.
- Published
- 2021
20. miR-124 and Androgen Receptor Signaling Inhibitors Repress Prostate Cancer Growth by Downregulating Androgen Receptor Splice Variants, EZH2, and Src
- Author
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Xu Bao Shi, Ralph W deVere White, Clifford G. Tepper, Regina F Gandour-Edwards, Hsing Jien Kung, Christopher P. Evans, Joy C. Yang, Hao G. Nguyen, Lingru Xue, Meimei Li, and Ai Hong Ma
- Subjects
Male ,Cancer Research ,Androgen ,Mice ,chemistry.chemical_compound ,Prostate cancer ,Receptors ,2.1 Biological and endogenous factors ,Protein Isoforms ,Aetiology ,Cancer ,Tumor ,Prostate Cancer ,EZH2 ,Polycomb Repressive Complex 2 ,Gene Expression Regulation, Neoplastic ,src-Family Kinases ,Oncology ,5.1 Pharmaceuticals ,Receptors, Androgen ,Development of treatments and therapeutic interventions ,Signal transduction ,Biotechnology ,Signal Transduction ,Proto-oncogene tyrosine-protein kinase Src ,Urologic Diseases ,Oncology and Carcinogenesis ,Down-Regulation ,Biology ,Article ,Cell Line ,Downregulation and upregulation ,Cell Line, Tumor ,microRNA ,Genetics ,medicine ,Animals ,Humans ,Enzalutamide ,Enhancer of Zeste Homolog 2 Protein ,Oncology & Carcinogenesis ,Neoplastic ,Prostatic Neoplasms ,medicine.disease ,Xenograft Model Antitumor Assays ,Molecular biology ,Androgen receptor ,MicroRNAs ,Gene Expression Regulation ,chemistry ,Cancer research - Abstract
miR-124 targets the androgen receptor (AR) transcript, acting as a tumor suppressor to broadly limit the growth of prostate cancer. In this study, we unraveled the mechanisms through which miR-124 acts in this setting. miR-124 inhibited proliferation of prostate cancer cells in vitro and sensitized them to inhibitors of androgen receptor signaling. Notably, miR-124 could restore the apoptotic response of cells resistant to enzalutamide, a drug approved for the treatment of castration-resistant prostate cancer. We used xenograft models to examine the effects of miR-124 in vivo when complexed with polyethylenimine-derived nanoparticles. Intravenous delivery of miR-124 was sufficient to inhibit tumor growth and to increase tumor cell apoptosis in combination with enzalutamide. Mechanistic investigations revealed that miR-124 directly downregulated AR splice variants AR-V4 and V7 along with EZH2 and Src, oncogenic targets that have been reported to contribute to prostate cancer progression and treatment resistance. Taken together, our results offer a preclinical rationale to evaluate miR-124 for cancer treatment. Cancer Res; 75(24); 5309–17. ©2015 AACR.
- Published
- 2015
21. Preferential degradation of long-chain alkyl substituted hydrocarbons in heavy oil under methanogenic conditions
- Author
-
Bo Tu, Lai yan Liu, Jan Dolfing, Qiang Li, Lei Cheng, Sheng bao Shi, Yahe Zhang, Yong ge Sun, Lu Yang, Lirong Dai, Hui Zhang, and Quan Shi
- Subjects
chemistry.chemical_classification ,010504 meteorology & atmospheric sciences ,biology ,chemistry.chemical_element ,Methanosarcina ,Methanothrix ,Biodegradation ,010502 geochemistry & geophysics ,biology.organism_classification ,01 natural sciences ,Methane ,chemistry.chemical_compound ,chemistry ,Geochemistry and Petrology ,Environmental chemistry ,Degradation (geology) ,Carbon ,Alkyl ,0105 earth and related environmental sciences ,Asphaltene - Abstract
Methanogenic crude oil degradation is a significant process in subsurface environments and degradation of crude oil n-alkanes has been well documented. However, little is known about the biodegradability of the resulting heavy oil. In this study, a methanogenic consortium enriched from Shengli oilfield generated 1.3–1.9 mmol CH4/g of heavy oil at a rate of 2.9–8.8 μmol CH4/g of oil/day. Four SARA fractions (saturates, aromatics, resins and asphaltenes) of oils experienced a loss in linear aliphatic structures. n-Alkylcyclohexanes, methyl-n-alkylcyclohexanes, n-alkyldecalins, n-alkylbenzenes, n-alkyltoluenes and n-alkylxylenes with alkyl side chains longer than 14 carbons were degraded over 50% compared to the undegraded oil. In addition, the extent of degradation of these hydrocarbons increased with increasing carbon length. Correspondingly, n-fatty acids and naphthenic acids with 1–3 naphthenic rings accumulated over time. 16S rRNA gene analysis revealed that aceticlastic Methanosarcina and Methanothrix dominated in the archaeal domain, and bacterial members related to Dehalococcoidia and Soehngenia were consistently present in the successive transfer cultures. However, neither assA/masD-like genes nor alkyl-substituted succinate metabolites were detected, indicating an alternative degradation pathway, rather than addition to fumarate. This study provides novel insights into methanogenic degradation of long-chain alkyl substituted hydrocarbons in heavy oil, which also extends our understanding of anaerobic degradation of crude oil in subsurface sedimentary environments.
- Published
- 2019
22. Alkaloids isolated from Tabernaemontana bufalina display xanthine oxidase inhibitory activity
- Author
-
Mei-Fen Bao, Jing Chen, Ying Zeng, Xiang-Hai Cai, and Bao-Bao Shi
- Subjects
Models, Molecular ,0106 biological sciences ,Xanthine Oxidase ,Apparicine ,Tabernaemontana ,medicine.drug_class ,Stereochemistry ,Allopurinol ,Plant Science ,Horticulture ,01 natural sciences ,Biochemistry ,Inhibitory Concentration 50 ,chemistry.chemical_compound ,Tabernaemontana bufalina ,Alkaloids ,Catalytic Domain ,medicine ,heterocyclic compounds ,Enzyme Inhibitors ,Isoquinoline ,Xanthine oxidase ,Molecular Biology ,Xanthine oxidase inhibitor ,Indole test ,010405 organic chemistry ,Chemistry ,Alkaloid ,General Medicine ,0104 chemical sciences ,010606 plant biology & botany ,medicine.drug - Abstract
Continued interest in bioactive alkaloids led to the isolation of four undescribed alkaloids along with 74 known ones from the aerial parts of Tabernaemontana bufalina Lour. The structures of the yet undescribed alkaloids were elucidated based on NMR, IR, UV, MS and CD spectroscopic data and X-ray crystal diffraction and, according to the plant source, named as taberhaines A–D (1–4). The known compounds comprised of 66 monoterpenoid indole, three carboline and five isoquinoline alkaloids. Among them, the known apparicine inhibited significantly the activity of xanthine oxidase, which plays an important role for gout, with an IC50 value of 0.65 μM, compared to the standard drug allopurinol (IC50 = 0.60 μM).
- Published
- 2019
23. Characterization of flexible radar-absorbing materials based on ferromagnetic nickel micron-fibers
- Author
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Xiaogang Chen, Sainan Wei, Ruosi Yan, and Bao Shi
- Subjects
010302 applied physics ,Materials science ,Polymers and Plastics ,Materials Science (miscellaneous) ,chemistry.chemical_element ,Nanotechnology ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Industrial and Manufacturing Engineering ,Characterization (materials science) ,law.invention ,Nickel ,Condensed Matter::Materials Science ,Ferromagnetism ,chemistry ,Stealth technology ,law ,0103 physical sciences ,Chemical Engineering (miscellaneous) ,Condensed Matter::Strongly Correlated Electrons ,Radar ,0210 nano-technology - Abstract
Flexible radar-absorbing materials have great application significance in stealth technology. In this paper, a novel radar-absorbing material based on ferromagnetic nickel micron-fibers with 38–40mm length and 10–12 mm diameter was successfully prepared through bundle-fiber drawing and electrochemical treatment. The characterization of morphology, chemical composition, magnetic and mechanical properties, including tensile strength, bending rigidity and friction, of the prepared ferromagnetic nickel micron-fiber is investigated. The results showed that compared with conventional radar absorbers, ferromagnetic nickel micron-fibers have many advantages in theirappearance and magnetic performance. The total ferromagnetic metal fraction of Ni and Fe was above 90%. Irregular cross-section and large aspect ratio of 3800 of the fiber enabled the magnetic hysteresis loss and absorbing performance to be increased obviously. Its saturation magnetization Ms was 116 emu/g with coercivity Hc of 5.8103A/m, initial permeability of 2036 H/m and Curie temperature of 996 K, confirming the fiber performed a relatively strong magnetic absorbing effect and high temperature stability. The tensile and friction properties of ferromagnetic nickel micron-fiber were also analyzed to evaluate the spinnability.
- Published
- 2018
24. Research of Wave Absorption Yarn Based on Nickel-iron Fiber
- Author
-
Sai-Nan Wei, Ya-Ning Hu, and Bao Shi
- Subjects
Metal fiber ,Materials science ,chemistry.chemical_element ,Yarn ,Wave absorption ,Polyester ,Nickel ,chemistry ,visual_art ,visual_art.visual_art_medium ,Fiber ,Composite material ,Spinning ,Fire retardant - Abstract
Flexible wave-absorbing fabric can overcome the defects of current hard absorbers, such as poor properties of shape adaptability, portability and restricted applications. Spinning functional yarns successfully plays a critical role in development of flexible fabric. In this study, three kinds of 58.3tex blended yarn of iron fiber and retardant polyester fiber were spun successfully, which nickel-iron fiber (NI fiber) content were 10%, 15% and 20%. Sliver mixed way of retardant polyester fiber and NI fiber was used. And the yarn performances were tested. The results showed that with the increase of the content of metal fiber, the yarn hairiness increased gradually, the strength decreased gradually and the abrasion resistance did not change obviously.
- Published
- 2017
25. Urate promotes SNCA/α-synuclein clearance via regulating mTOR-dependent macroautophagy
- Author
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Xian Cao, Li-Fang Hu, Bao-Shi Yuan, Xiao-Ou Hou, Weifeng Luo, Yu-Lan Sheng, Qi-Lin Zhang, Xin Yuan, Xing Chen, Chun-Feng Liu, and Yu-Qing Yuan
- Subjects
0301 basic medicine ,Autophagosome ,Genetically modified mouse ,Male ,Cell Survival ,Metabolic Clearance Rate ,Mice, Transgenic ,Pilot Projects ,Biology ,PC12 Cells ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Developmental Neuroscience ,Autophagy ,Animals ,Humans ,PI3K/AKT/mTOR pathway ,Dose-Response Relationship, Drug ,Activator (genetics) ,TOR Serine-Threonine Kinases ,Wild type ,Bafilomycin ,ULK1 ,Cell biology ,Rats ,Uric Acid ,Mice, Inbred C57BL ,030104 developmental biology ,Neurology ,chemistry ,Biochemistry ,alpha-Synuclein ,030217 neurology & neurosurgery - Abstract
Serum urate levels are reported to be significantly lowered in patients with Parkinson's disease (PD) and inversely correlated to the risk and progression of PD. However, the mechanism by which urate affects PD is poorly understood. Here we showed that treatment with uric acid (UA) resulted in an autophagy activity enhancement in PC12 cells in dose- and time-dependent manners, as indicated by LC3-II increase and P62 decrease. Moreover, UA was still able to increase the LC3-II level and the number of LC3 puncta in the presence of Bafilomycin A1, a lysosomal inhibitor. These changes of autophagic markers were preceded by mTOR inhibition and ULK1 activation. Co-treatment with 3-benzyl-5-((2-nitrophenoxy) methyl)-dihydrofuran-2(3H)-one (3BDO), an mTOR activator, abolished the UA-induced LC3-II increase. More importantly, UA reduced SNCA/α-synuclein accumulation in PC12 cells that overexpress wildtype or A53T mutant SNCA, and this was blocked by Bafilomycin A1 co-treatment. The in vivo study showed that UA administration was able to modulate the levels of autophagy markers, increase the autophagosome/autolysosome formation, and reduce SNCA accumulation in the midbrain of SNCAA53T transgenic mice. Taken together, our findings suggest that UA could induce autophagy activation via an mTOR-dependent signaling and ameliorate SNCA accumulation. This implicates that urate-elevating agent may become a potential strategy for PD therapy.
- Published
- 2017
26. The Compensation of Y Waveguide Temperature Drifts in FOG with the Thermal Resistor
- Author
-
Ying Li Wang, Liyong Ren, Jin-Tao Xu, Kai Li Ren, Nian Bao Shi, Jian Liang, and Meng Hua Kang
- Subjects
Optical fiber ,Materials science ,business.industry ,Lithium niobate ,General Engineering ,Physics::Optics ,Gyroscope ,Fibre optic gyroscope ,Waveguide (optics) ,law.invention ,Compensation (engineering) ,chemistry.chemical_compound ,Optics ,chemistry ,law ,business ,Electronic circuit ,Voltage - Abstract
The lithium niobate integrated optical phase modulator (Y waveguide) is the key device in the digital closed-loop fiber optic gyroscope. However, the half-wave voltage of the lithium niobate changes with the environment temperature, which produces the phase bias drift and ultimately decreases the accuracy of FOG. In this manuscript, the thermal resistor is introduced in the amplification part in the driving circuits of Y waveguide. Due to the characteristic of the thermal resistor, the magnitude of driving voltage on Y waveguide changed with temperature to compensate the electro-optic effects temperature drift of the lithium niobate. This method was proved to improve the performance of fiber optic gyroscopes conveniently in experiment.
- Published
- 2014
27. Targeting autophagy overcomes Enzalutamide resistance in castration-resistant prostate cancer cells and improves therapeutic response in a xenograft model
- Author
-
Yang Jinyong, Derya Tilki, Hao G. Nguyen, Primo N. Lara, Hsing Jien Kung, Allen C. Gao, R. W. Devere White, Christopher P. Evans, and Xu-Bao Shi
- Subjects
Male ,Aging ,Cancer Research ,Mice, SCID ,Pharmacology ,Castration-Resistant ,Mice ,chemistry.chemical_compound ,Prostate cancer ,0302 clinical medicine ,Cancer ,0303 health sciences ,Tumor ,Prostate Cancer ,Chloroquine ,Metformin ,3. Good health ,Gene Expression Regulation, Neoplastic ,Prostatic Neoplasms, Castration-Resistant ,5.1 Pharmaceuticals ,030220 oncology & carcinogenesis ,Benzamides ,Original Article ,Development of treatments and therapeutic interventions ,Signal Transduction ,medicine.drug ,Urologic Diseases ,Programmed cell death ,Bicalutamide ,Clinical Sciences ,Oncology and Carcinogenesis ,Biology ,SCID ,Cell Line ,03 medical and health sciences ,Cell Line, Tumor ,Nitriles ,Phenylthiohydantoin ,Autophagy ,Androgen Receptor Antagonists ,Genetics ,medicine ,Animals ,Humans ,Enzalutamide ,Oncology & Carcinogenesis ,Molecular Biology ,PI3K/AKT/mTOR pathway ,030304 developmental biology ,Neoplastic ,Prostatic Neoplasms ,AMPK ,medicine.disease ,Xenograft Model Antitumor Assays ,Androgen receptor ,Gene Expression Regulation ,chemistry ,Clomipramine - Abstract
Macro-autophagy is associated with drug resistance in various cancers and can function as an adaptive response to maintain cell survival under metabolic stresses, including androgen deprivation. Androgen deprivation or treatment with androgen receptor (AR) signaling inhibitor (ARSI), Enzalutamide (MDV-3100, ENZA) or bicalutamide induced autophagy in androgen-dependent and in castration-resistant CaP (castration-resistant prostate cancer (CRPC)) cell lines. The autophagic cascade triggered by AR blockage, correlated with the increased light chain 3-II/I ratio and ATG-5 expression. Autophagy was observed in a subpopulation of C4-2B cells that developed insensitivity to ENZA after sustained exposure in culture. Using flow cytometry and clonogenic assays, we showed that inhibiting autophagy with clomipramine (CMI), chloroquine or metformin increased apoptosis and significantly impaired cell viability. This autophagic process was mediated by AMP-dependent protein kinase (AMPK) activation and the suppression of mammalian target of rapamycin (mTOR) through Raptor phosphorylation (Serine 792). Furthermore, small interfering RNA targeting AMPK significantly inhibited autophagy and promoted cell death in CaP cells acutely or chronically exposed to ENZA or androgen deprivation, suggesting that autophagy is an important survival mechanism in CRPC. Lastly, in vivo studies with mice orthotopically implanted with ENZA-resistant cells demonstrated that the combination of ENZA and autophagy modulators, CMI or metformin significantly reduced tumor growth when compared with control groups (P
- Published
- 2014
28. Optimising pulsed microwave-vacuum puffing for Shiitake mushroom (Lentinula edodes) caps and comparison of characteristics obtained using three puffing methods
- Author
-
Xue-Dong Chang, Peng-Bao Shi, Li-Jie Liu, and Su-Wen Liu
- Subjects
Mushroom ,biology ,Central composite design ,Chemistry ,Vacuum pressure ,biology.organism_classification ,Industrial and Manufacturing Engineering ,Expansion ratio ,Lentinula ,Response surface methodology ,Food science ,Water content ,Microwave ,Food Science - Abstract
Summary Shiitake mushroom (Lentinula edodes) caps were puffed using pulsed microwave-vacuum puffing (PMVP), microwave-vacuum puffing (MVP) and microwave puffing (MP). The response surface method was used to optimise the process parameters for using PMVP to puff mushroom caps. The experiments were conducted using a central composite design to determine the visual appearance and initial moisture content (30–50%) of the mushroom caps. The initial moisture content and microwave power intensity showed highly significant linear relations with the expansion ratio and sensory evaluation. The optimal conditions for puffing mushroom caps were initial moisture content, microwave intensity, vacuum pressure and pulse ratio of 35%, 40 W g−1, 77.5 ± 1.5 kPa and 1.35, which resulted in an optimal expansion ratio and sensory score of 163.2% and 6.83, respectively. The caps puffed using PMVP showed better textures, sensory scores and microstructures than those puffed using either MP or MVP.
- Published
- 2014
29. Phenolic Profile and Antioxidant Capacity of Ten Dry Red Wines from Two Major Wine-producing Regions in China
- Author
-
Peng-bao Shi, Feng-Mei Zhu, Bin Du, and Feng-Ying Li
- Subjects
Wine ,ABTS ,Sweetness of wine ,DPPH ,digestive, oral, and skin physiology ,food and beverages ,General Chemistry ,Industrial and Manufacturing Engineering ,chemistry.chemical_compound ,chemistry ,Chlorogenic acid ,Polyphenol ,Botany ,Caffeic acid ,Gallic acid ,Food science ,Food Science - Abstract
Ten dry red wines, produced two major wine-producing regions from China-Changli in Hebei Province and Yantai in Shandong Province, were examined in this study. The antioxidant activities of wines were measured by different analytical methods: 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) radical scavenging activity, 2, 2-azino-di- (3-ethylbenzothialozine-sulphonic acid) (ABTS) radical scavenging activity and Ferric Reducing Antioxidant Power (FRAP). Furthermore, total phenols, total flavonoids and seven individual phenolic compounds (Gallic acid; Catechin; Chlorogenic acid; Caffeic acid; Ferulic acid; Rutin and Morin) of wines were also determined. The results showed that sample 9 (College dry red wine, Cabernet Sauvignon, 2011) contained the highest total phenol content, up to 2131 mg/L; sample 7 (Great Wall dry red wine, Cabernet Sauvignon, Yantai) contained the highest total flavonoids, up to 1282 mg/L. Seven individual phenolics in wine samples were detected by Reverse Phase High Performance Liquid Chromatography (RP-HPLC). Different types of dry red wine polyphenols on DPPH scavenging rate from 78.88 to 98.55%, the highest FRAP scavenging activity was up to 222.66 μmol/L, the lowest was 189.51 μmol/L, different types of wine polyphenols have high ABTS scavenging activity. The current findings will provide useful information for evaluating the wine quality and for educating consumers to choose specific dry wine for specific health-promoting effects.
- Published
- 2014
30. Screen-Printed Si Paste for Localized B Doping in a Back Surface Field
- Author
-
Bao Shi, Wei Wang, Juan Hong, and Wei Zhang
- Subjects
Materials science ,Silicon ,Annealing (metallurgy) ,Doping ,Analytical chemistry ,Nanoparticle ,chemistry.chemical_element ,Laser ,Electronic, Optical and Magnetic Materials ,law.invention ,Back surface field ,chemistry ,law ,Electric discharge ,Wafer ,Electrical and Electronic Engineering - Abstract
In this letter, Si paste formed by p-type Si nanoparticles (NPs) and an organic solvent is used as the source of B. Si NPs with a diameter of $\sim 30$ nm are prepared using the pulsed electrical discharge method. The preprocessed Si wafers (after laser opening) are used as the substrate. Si paste with different percentages of Si NPs is screen-printed above the openings. B atoms diffuse into Si wafers through annealing. Uniform doping profiles are observed under a laser scanning microscope. The B doping is successful as evidenced by secondary ion mass spectroscopy.
- Published
- 2015
31. Isolation of biphenyl-degrading microorganism and its cometabolic transformation of polychlorinated biphenyls (PCBs)
- Author
-
Bao Shi long, Liu She jiang, Liang Wen juan, Zhao Lin, and Qi Yun
- Subjects
Biphenyl ,Strain (chemistry) ,Microorganism ,food and beverages ,Plant Science ,Biology ,biology.organism_classification ,Microbiology ,chemistry.chemical_compound ,Infectious Diseases ,Bioremediation ,Activated sludge ,Paracoccus ,chemistry ,Bioaccumulation ,Environmental chemistry ,bacteria ,Energy source - Abstract
Polychlorinated biphenyls (PCBs) are ubiquitous pollutions that cause public concern due to their long persistence, low degradability, strong bioaccumulation and high toxicity in the environment. A bacterium strain G-2 was isolated from an activated sludge of a chemical factory wastewater treatment plant in China. Based on its phenotypic typing coupled with 16S rRNA gene analysis, the strain was classified as Paracoccus sp. The strain G-2 can use biphenyl as sole carbon and energy sources, and almost complete degraded it within 7 days. Although this strain can only utilize 24% of PCB 77, more substrate may degrade when added biphenyl as cometabolic compound. The result may provide evidence for the potential application of Paracoccus in bioremediation of PCB-contaminated soil.
- Published
- 2012
32. The establishment of biological reference intervals of nontraditional glycemic markers in a Chinese population
- Author
-
Liying Lv, De-Bao Shi, and Qiang Zhou
- Subjects
Microbiology (medical) ,Adult ,Blood Glucose ,Glycation End Products, Advanced ,Male ,030213 general clinical medicine ,medicine.medical_specialty ,Clinical Biochemistry ,030209 endocrinology & metabolism ,Deoxyglucose ,03 medical and health sciences ,chemistry.chemical_compound ,Young Adult ,0302 clinical medicine ,Glycated albumin ,Asian People ,Reference Values ,Internal medicine ,medicine ,Immunology and Allergy ,Humans ,Glycated Serum Albumin ,Serum Albumin ,Research Articles ,Glycemic ,Aged ,Chinese population ,business.industry ,Healthy population ,Biochemistry (medical) ,Public Health, Environmental and Occupational Health ,Hematology ,Middle Aged ,Reference intervals ,Medical Laboratory Technology ,Fructosamine ,Endocrinology ,chemistry ,1,5-Anhydroglucitol ,Female ,business ,Biomarkers ,Blood Chemical Analysis - Abstract
BACKGROUND: We established the reference intervals for glycated albumin (GA), fructosamine (FA), and 1,5‐anhydroglucitol (1,5‐AG) in a Chinese healthy population. METHODS: This study enrolled a total of 458 eligible reference individuals, consisted of 226 men and 232 women, aged from 20~79 years (median age 43 years), who attending routine healthy checks. We stratified the subjects according to gender (males and females) and age (20‐39, 40‐59, and 60‐79 years), and combined statistical methods with Lahti algorithm, as well as appropriate clinical consideration, to judge whether partitioning for data was needed. RESULTS: Glycated albumin levels between males and females were statistically different (P.05). The reference interval for FA was 220‐298 μmol/L. CONCLUSION: New reference intervals for nontraditional glycemic markers were established based on a Chinese population.
- Published
- 2016
33. Dual role of IGF-II in oocyte maturation in southern flounder Paralichthys lethostigma: Up-regulation of mPRα and resumption of meiosis
- Author
-
Matthew E. Picha, Peter Thomas, and Bao Shi
- Subjects
endocrine system ,medicine.medical_specialty ,medicine.medical_treatment ,Molecular Sequence Data ,Flounder ,Biology ,Cycloheximide ,Andrology ,Wortmannin ,Insulin-like growth factor ,chemistry.chemical_compound ,Oogenesis ,Endocrinology ,Insulin-Like Growth Factor II ,Internal medicine ,medicine ,Animals ,Amino Acid Sequence ,Cloning, Molecular ,Insulin-Like Growth Factor I ,Receptor ,Incubation ,Germinal vesicle ,Sequence Homology, Amino Acid ,urogenital system ,Ovary ,Cell Differentiation ,Membrane progestin receptor alpha ,Oocyte ,Up-Regulation ,Meiosis ,medicine.anatomical_structure ,chemistry ,Oocytes ,Female ,Animal Science and Zoology ,Receptors, Progesterone - Abstract
Increasing evidence suggests a regulatory role for the IGF system in teleost oocyte maturation (OM). Our objectives were to determine if IGF-I and IGF-II regulate different stages of OM in southern flounder (Paralichthys lethostigma) and to identify the likely maturation-inducing steroid (MIS) in this species. The most abundant final product of ovarian steroidogenesis assays eluted at the position of 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S). 20β-S was also more potent in inducing germinal vesicle breakdown (GVBD) of maturationally-competent oocytes than other teleost MISs. IGF-II (100 nM) induced maturational competence (OMC), as greater GVBD was induced after incubation with IGF-II+20β-S compared to that of the 20β-S+20β-S or IGF-II+no treatment group. Incubation with IGF-II (100 nM) for 4-8 h significantly increased ovarian membrane progestin receptor alpha (mPRα or Paqr7b) mRNA levels 12-15% and mPRα protein levels 75-101%. Further, the IGF-II-induced increase in mPRα protein concentrations was partially blocked by pretreatment with Wortmannin, a Pik3 inhibitor, and PD 098,059, a Mapk inhibitor. Both IGF-I and -II (100 nM) induced GVBD of maturationally-competent oocytes was blocked by incubation with cycloheximide. Incubation with D,L-Aminoglutethimide decreased IGF-II-induced GVBD but had no effect on IGF-I-induced GVBD. IGF-I and -II were also able to induce GVBD of maturationally-incompetent oocytes, and elicited 75% and 135% greater GVBD, respectively, than hCG+20β-S at 100 nM. In conclusion, we show that 20β-S is the likely MIS in this species and that IGF-I and -II are also able to induce GVBD. Further, IGF-II not only induces OMC but also up-regulates ovarian mPRα mRNA and protein through Pik3- and Mapk-dependent pathways. This is the first demonstration of mPRα regulation by an IGF in any vertebrate species.
- Published
- 2012
34. Probing into the effect of Auger recombination mechanism on zero bias resistance–area product in In1−xGaxAs detector
- Author
-
Fubin Gao, Yuchun Chang, Jingzhi Yin, Bao Shi, Longhai Li, Guotong Du, and Yixin Jin
- Subjects
Recombination velocity ,Auger effect ,Chemistry ,Infrared ,Detector ,Analytical chemistry ,Photodetector ,General Chemistry ,Condensed Matter Physics ,symbols.namesake ,Product (mathematics) ,Materials Chemistry ,symbols ,Figure of merit ,Zero bias ,Atomic physics - Abstract
D * (Detectivity), an important figure of merit for photodetectors, is limited by zero bias resistance–area product ( R 0 A ) . R 0 A is determined by Auger recombination mechanism, depending on the composition, temperature, carrier concentration and other parameters of the photodetectors. To investigate R 0 A of In1−xGaxAs infrared photodetectors, in this paper, theoretical analysis of Auger recombination mechanism was carried out in the room temperature, by taking CCCH, CHHL and CHHS into account. The calculated results show that there are significant influences on R 0 A for various parameters in both p- and n-type regions of the devices. With carrier concentration around 1017 to 1018 cm−3, R 0 A of 108 Ω cm2 (n-region) and 106 Ω cm2 (p-region) are obtained for x = 0.47 , when thickness and surface recombination velocity of the sample are 5 μm and 100 m/s, respectively.
- Published
- 2011
35. Application of chlorinated waste rubber as a flame retardant of low density polyethylene
- Author
-
Yingzhou Lu, Xiaosui Chen, Bao-Shi Yan, Chunxi Li, and Kui-Long Tan
- Subjects
Thermogravimetric analysis ,Materials science ,Polymers and Plastics ,chemistry.chemical_element ,General Chemistry ,Surfaces, Coatings and Films ,Limiting oxygen index ,Low-density polyethylene ,Chemical engineering ,chemistry ,Reagent ,Materials Chemistry ,Chlorine ,Char ,Fourier transform infrared spectroscopy ,Composite material ,Fire retardant - Abstract
For the reuse of the abundant waste rubber (WR), chlorinated waste rubber (Cl-WR) was prepared by a water-based chlorination method using chlorine gas as the chlorinating reagent. The resultant Cl-WR was used as a flame retardant of low density polyethylene (LDPE) matrix. The properties of WR and Cl-WR were characterized by thermogravimetric (TG) and Fourier transform infrared (FTIR) spectrometer. The results indicated that the Cl-WR with a 42% chlorine content had a higher char residue than WR. The limiting oxygen index (LOI) value can be increased up to 27.2 and the flame retardancy reached to the maximum (V-0) grade for the LDPE/Cl-WR-Sb blends with mass ratios of Cl-WR/LDPE and Cl-WR/Sb2O3 being 80/100 and 1.5/1, respectively. The improvement of the flame retardancy and thermal properties of the LDPE/Cl-WR-Sb blends were attributed to the char formation and synergistic effect between Cl-WR and Sb2O3 in a high temperature region, although the mechanical properties of the said blend decreased in comparison with that of the neat LDPE. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
- Published
- 2011
36. Study on Granulation of Anaerobic Sludge in UASB Reactor Adding Cationic Polymer Treating Low Strength Wastewater at Room Temperature
- Author
-
Xiao Hui Fu, Zong Lian She, Meng Chun Gao, En Shi, Jian Wu, and Bao Shi Li
- Subjects
Granulation ,Wastewater ,Anaerobic sludge ,Waste management ,Chemistry ,Lab scale ,Cationic polymerization ,General Medicine ,Pulp and paper industry ,Effluent - Abstract
Effect of cationic polymer on granulation and COD removal efficiency in lab scale UASB reactors was examined, treating low-strength wastewater (COD 300-500mg l-1) at room temperature. It was shown that cationic polymer was more effective for enhancing sludge granulation and COD removal efficiency as compared to the control experiment (without additives). After day 166 of operation, the amount of granules size above 0.5mm accounted for 32.1% of total sludge, higher than that of control experiment (19.3%). At 1.03 kg COD m-3 d-1 of OLR and 9.8 h of HRT, the effluent VFA had a maximum value of 168mg l-1 and 240mg l-1 in Reactor A and B respectively. The polymer-amended reactor took 36days to receive 1.44 kg COD m-3 d-1 of OLR at the 7.8 h of HRT, shorter than the control reactor (54days). The two reactors obtained above 80% in COD removal efficiency. It is shown that UASB reactor can also achieve higher COD removal treating low strength wastewater at room temperature.
- Published
- 2011
37. Identification of 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S) receptor binding and membrane progestin receptor alpha on southern flounder sperm (Paralichthys lethostigma) and their likely role in 20β-S stimulation of sperm hypermotility
- Author
-
Wenxian Tan, Bao Shi, Christopher Tubbs, and Peter Thomas
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,G protein ,Cortodoxone ,Molecular Sequence Data ,Flounder ,Adenylyl cyclase ,chemistry.chemical_compound ,Endocrinology ,Internal medicine ,medicine ,Animals ,Amino Acid Sequence ,Receptor ,reproductive and urinary physiology ,Sperm motility ,Southern flounder ,biology ,urogenital system ,Membrane progestin receptor alpha ,biology.organism_classification ,Sperm ,chemistry ,Dideoxyadenosine ,Sperm Motility ,Animal Science and Zoology ,Receptors, Progesterone ,Sequence Alignment - Abstract
The existence of direct progestin actions on teleost sperm to stimulate hypermotility is not widely acknowledged because it has only been demonstrated in members of the family Sciaenidae. In the present study, progestin stimulation of sperm hypermotility was investigated in a non-sciaenid, southern flounder, and the potential role of membrane progestin receptor alpha (mPRα or Paqr7b) in mediating this action was examined. The major progestin produced in vitro by flounder testicular fragments co-migrated with 17,20β,21-trihydroxy-4-pregnen-3-one (20β-S) during thin-layer chromatography. Treatment of flounder sperm with 5 nM-100 nM 20β-S significantly increased sperm velocity in vitro , whereas 17,20β-dihydroxy-4-pregnen-3-one and other steroids were ineffective. A single class of high affinity ( K d 22.95 nM), saturable, limited-capacity binding sites ( B max 0.013 nM) specific for 20β-S was identified on sperm membranes. Treatment of sperm membranes with guanosine 5′-(3- O -thio)triphosphate reduced [ 3 H]-20β-S binding, suggesting the 20β-S receptor couples to a G protein. The membrane adenylyl cyclase inhibitor 2′,5′-dideoxyadenosine blocked 20β-S-induced sperm hypermotility, indicating 20β-S activates stimulatory G proteins. Finally, flounder paqr7b was cloned and characterized from testicular tissues. The Paqr7b protein is expressed on the midpiece of flounder sperm and is more abundant in individuals with high sperm motility than low motility donors. These findings suggest that 20β-S stimulates sperm hypermotility in flounder through activation of stimulatory G proteins, likely through Paqr7b. The finding that progestins directly stimulate sperm hypermotility in a flatfish, a highly derived species not belonging to the teleost family Sciaenidae, suggests this phenomenon is widespread among advanced fishes.
- Published
- 2011
38. Down-regulation of microRNA 106b is involved in p21-mediated cell cycle arrest in response to radiation in prostate cancer cells
- Author
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Clifford K.S. Chao, Dattatreyudu Nori, B. Li, Ralph W deVere White, Allen M. Chen, Richard K. Valicenti, and Xu Bao Shi
- Subjects
Regulation of gene expression ,Cell cycle checkpoint ,Cell growth ,Urology ,Transfection ,Biology ,Cell biology ,chemistry.chemical_compound ,Oncology ,chemistry ,RNA interference ,LNCaP ,microRNA ,Growth inhibition - Abstract
BACKGROUND microRNAs (miRNAs) are endogenous short non-coding RNAs, and play a pivotal role in regulating of a variety of cellular processes, including proliferation and apoptosis, both of which are cellular responses to radiation treatment. The purpose of this study is to identify candidate miRNAs whose levels are altered in response to radiation in prostate cancer cells and to investigate the molecular pathway of such miRNAs in the regulation of radiation-induced cellular response. METHODS Using a miRNA microarray assay, we screened 132 cancerous miRNAs in LNCaP cells in response to radiation treatment. The function of one candidate miRNA was investigated for checkpoint protein expression, cell cycle arrest, cell proliferation, and cell survival in cells transfected with precursor or antisense miRNA. RESULTS In response to radiation, multiple miRNAs, including mi-106b, showed altered expression. Cells transfected with precursor miR-106b were able to suppress radiation-induced p21 activation. Functionally, exogenous addition of precursor miR-106b overrode the G2/M arrest in response to radiation and resulted in a transient diminishment of radiation-induced growth inhibition. CONCLUSION We have shown a novel role of miR-106b, in the setting of radiation treatment, in regulating the p21-activated cell cycle arrest. Our finding that miR-106b is able to override radiation-induced cell cycle arrest and cell growth inhibition points to a potential therapeutic target in certain prostate cancer cells whose radiation resistance is likely due to consistently elevated level of miR-106b. Prostate 71:567–574, 2011. © 2010 Wiley-Liss, Inc.
- Published
- 2010
39. Catalyst-free and solvent-free method for the synthesis of quinoxalines under microwave irradiation
- Author
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Kun Bao Shi, San Jun Zhi, Jian Feng Zhou, and Gui Xia Gong
- Subjects
chemistry.chemical_compound ,Quinoxaline ,Solvent free ,Materials science ,chemistry ,Yield (chemistry) ,Microwave irradiation ,Proton NMR ,General Chemistry ,Benzil ,Carbon-13 NMR ,Catalysis ,Nuclear chemistry - Abstract
A facile procedure for the synthesis of quinoxalines is being reported starting from benzil and 1,2-diaminobenzene. The reactions were carried out catalyst-free, solvent-free and under microwave irradiation conditions in high yield (84–98%) with short time (3–6 min) and environmental benign, as well as convenient operation. The structures of all the compounds have been confirmed on the basis of their IR, 1H NMR, and/or 13C NMR, mass spectral data.
- Published
- 2009
40. Measurement of second-order nonlinear optical susceptibility of cBN crystal synthesized at high pressure and high temperature
- Author
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Zhanguo Chen, Bao Shi, Jianxun Zhao, Xiuhuan Liu, Gang Jia, Kun Cao, Ce Ren, and Tiechen Zhang
- Subjects
Materials science ,business.industry ,General Engineering ,Physics::Optics ,Nitride ,Laser ,law.invention ,Crystal ,Condensed Matter::Materials Science ,chemistry.chemical_compound ,Wavelength ,Semiconductor ,Optics ,chemistry ,law ,Boron nitride ,Optoelectronics ,Continuous wave ,Wafer ,business - Abstract
We demonstrate a transverse electro-optical modulator based on a tiny and irregular octahedral wafer of cubic boron nitride (cBN) crystal that is prepared by hexagonal boron nitride at high pressure and high temperature using nitride as the catalyst. A continuous wave semiconductor laser at the wavelength of 650nm is used as a light source. A novel electrode fabrication is designed, a developed method different from the conventional transverse electro-optical modulator is introduced and the expression of the intensity of output beam is thought over. We obtain the half-wave voltage based on experiments of transverse electro-optical modulation. The second-order nonlinear optical susceptibility @g"i"j"k^(^2^)(@w,0)=1.919x10^-^1^2m/V of cBN crystal is calculated by means of the half-wave voltage.
- Published
- 2009
41. Anisotropy of photocurrent for two-photon absorption photodetector made of hemispherical silicon with $(\overline{1}10)$ plane
- Author
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Xiuhuan Liu, Bao Shi, Jingxiang Zhao, Shuo Wang, Zhanguo Chen, Kun Cao, Yun Zhang, Ce Ren, and Gang Jia
- Subjects
Photocurrent ,Materials science ,Physics and Astronomy (miscellaneous) ,Silicon ,Condensed Matter::Other ,business.industry ,General Engineering ,Physics::Optics ,General Physics and Astronomy ,chemistry.chemical_element ,Photodetector ,Quantum Physics ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Two-photon absorption ,Wavelength ,Optics ,chemistry ,Continuous wave ,Optoelectronics ,business ,Anisotropy ,Absorption (electromagnetic radiation) - Abstract
We fabricated a hemispherical nearly-intrinsic Si-based photodetector with ( \(\bar{1}10)\) plane. The photocurrent generated from the detector under a continuous wave laser at the wavelength of 1.3 μm was observed. The photocurrent shows a quadratic dependence on the incident optical power. The dependence of the photocurrent on the azimuth of the incident optical field is consistent with the anisotropy of the two-photon absorption in Si crystals. The ratio of the two nonzero independent components of the third-order susceptibility of silicon is obtained to be 0.42 from the observed result of the anisotropy of the photocurrent.
- Published
- 2008
42. Scanning tunnelling microscope studies of growth of RuO 2 (110) thin layer on Ru(0001)
- Author
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Huang Han, Li Hai-Yang, Zhang Han-Jie, Bao Shi-Ning, He Pei-Mo, Lu Yun-Hao, and Lu Bin
- Subjects
Microscope ,Materials science ,Thin layer ,A domain ,General Physics and Astronomy ,chemistry.chemical_element ,Substrate (chemistry) ,Nanotechnology ,Oxygen ,law.invention ,Crystallography ,chemistry ,law ,Quantum tunnelling - Abstract
This paper reports that the growth of RuO2(110) thin layer growth on Ru(0001) has been investigated by means of scanning tunnelling microscope (STM). The STM images showed a domain structure with three rotational domains of RuO2(110) rotated by an angle of 120°. The as-grown RuO2(110) thin layer is expanded from the bulk-truncated RuO2(110) due to the large mismatch between RuO2(110) and the Ru(0001) substrate. The results also indicate that growth of RuO2(110) thin layer on the Ru(0001) substrate by oxidation tends first to formation of the Ru-O (oxygen) chains in the [001] direction of RuO2(110).
- Published
- 2006
43. Development of tumor targeting anti-MUC-1 multimer: effects of di-scFv unpaired cysteine location on PEGylation and tumor binding
- Author
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Arutselvan Natarajan, Gerald L. DeNardo, Xu Bao Shi, Sally J. DeNardo, and Cheng Yi Xiong
- Subjects
Glycosylation ,Immunoglobulin Variable Region ,chemical and pharmacologic phenomena ,Bioengineering ,Protein Engineering ,Transfection ,Biochemistry ,Chromatography, Affinity ,Epitope ,Polyethylene Glycols ,law.invention ,Maleimides ,chemistry.chemical_compound ,law ,Cell Line, Tumor ,Humans ,Cysteine ,Molecular Biology ,MUC1 ,Cysteine metabolism ,chemistry.chemical_classification ,Mucin-1 ,Epithelial Cells ,respiratory system ,Molecular biology ,Recombinant Proteins ,Amino acid ,chemistry ,PEGylation ,Recombinant DNA ,Linker ,Biotechnology - Abstract
MUC1 mucin expressed in epithelial cancer, such as prostate and breast, is aberrantly glycosylated providing unique targets for imaging and therapy. In order to create a broadly applicable construct to target these unique epitopes on metastatic cancer, we selected an antibody fragment (scFv) that binds both synthetic MUC1 core peptide and epithelial cancer cell-expressed MUC1, and developed a recombinant bivalent molecule (di-scFv). Genetically engineered modifications of the di-scFv were constructed to create five molecular versions, each having a free cysteine (di-scFv-c) at different locations for site-specific conjugation. The effects of the engineered cysteine in the varied sites were studied relative to tumor binding and polyethylene glycol-maleimide (PEG-Mal) conjugation (PEGylation). Escherichia coli production as well as binding to MUC1 core peptide, human tumor cell lines and human tumor biopsies, were comparable. However, the location of the engineered cysteine in these di-scFv-c did influence PEGylation efficiency of this free thiol; higher PEGylation efficiency occurred with this cysteine in the inter-scFv linkage. Di-scFv-c PEG, with the cysteine engineered after the fifth amino acid in the linker, was used as an example to demonstrate comparable antigen-binding to non-PEGylated di-scFv-c. In summary, novel anti-MUC1 di-scFv-c molecules can be efficiently produced, purified and conjugated by site-specific PEGylation without loss of immunoreactivity, thus providing flexible multidentate constructs for cancer-targeted imaging and therapy.
- Published
- 2006
44. Influence of isothermal quenching of LAMC CrMnSi cast steel on impact toughness
- Author
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Zhi-qiu Huang, Bao-shi Jin, and Da-dong Shen
- Subjects
Quenching ,Austenite ,Materials science ,Scanning electron microscope ,Bainite ,Mechanical Engineering ,Metallurgy ,chemistry.chemical_element ,Microstructure ,Isothermal process ,chemistry ,Mechanics of Materials ,Dimple ,General Materials Science ,Composite material ,Carbon - Abstract
The influence of isothermal quenching process of low-alloy and medium carbon (LAMC) CrMnSi cast steel on the impact toughness was investigated. The microstructure and mechanical property of LAMC CrMnSi cast steel were analyzed by the laser optical modulator, the scanning electron microscopy, the energy dispersive spectrometer, the hardness and impact tests. The experimental results show that the dual phases of bainite and residual austenite can be obtained by the severity isothermal quenching, the fractographies of specimens change from quasicleavage to dimple at 310 °C for 60 min, the impact toughness for specimens at the room temperature isothermally achieves 130 J/cm2, meantime and its hardness is more than 45 (HRC).
- Published
- 2005
45. The electronic states of ordered thin films of perylene on Ag (110)
- Author
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Li Hai-Yang, Huang Han, Qian Hui-Qin, Yan Xinzheng, Mao Hong-Ying, He Pi-Mo, Bao Shi-Ning, Chen Qiao, and Zhang Jianhua
- Subjects
Materials science ,Photoemission spectroscopy ,business.industry ,Fermi level ,Analytical chemistry ,Substrate (electronics) ,Electronic structure ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,symbols.namesake ,Optics ,chemistry ,Electron diffraction ,Monolayer ,symbols ,Electrical and Electronic Engineering ,Thin film ,business ,Perylene - Abstract
The growth of perylene on Ag (1 1 0) has been studied by ultraviolet photoemission spectroscopy measurements and low-energy electron diffraction. Four emission features of the organic material are located at 3.5, 4.8, 6.4 and 8.5 eV, respectively, below the Fermi level. An ordered structure of c(6×2) can be observed when the organic film is about a monolayer (3 A thickness). The angle-resolved ultraviolet photoemission spectroscopy measurements show that the molecular plane of perylene near the interface is parallel to the substrate. The desorption of the organic material occurs with warming the substrate; the perylene molecules are stable on the Ag (1 1 0) surface and no decomposition is observed below 140°C.
- Published
- 2004
46. Study on the stages of N,N-dibutyl–3,4,9,10-perylene tetracarboxylic diimide growth on Ru (0001) surface
- Author
-
Li Hai-Yang, Zhang Jianhua, Wu Yue, Yang Xin-Guo, Yang Fan, Wang Mang, Sun Jingzhi, Bao Shi-Ning, and He Pi-Mo
- Subjects
Materials science ,Photoemission spectroscopy ,Thermal decomposition ,Substrate (chemistry) ,Condensed Matter Physics ,Photochemistry ,Electronic, Optical and Magnetic Materials ,Organic semiconductor ,chemistry.chemical_compound ,Adsorption ,chemistry ,Diimide ,Desorption ,Electrical and Electronic Engineering ,Perylene - Abstract
The stages of N , N- dialkyl-3,4,9,10-perylene tetracarboxylic diimide derivatives growth on Ru (0 0 0 1) surface has been studied with the ultraviolet photoemission spectroscopy measurements, three emission features of the organic material are located at 2.9, 4.8 and 6.7 eV, respectively below the Fermi level. The angle-resolved ultraviolet photoemission spectroscopy results suggest that the organic molecule is parallel to the substrate surface. Desorption of the organic material in multilayer occurs with warming the substrate. The decomposition of the adsorbed organic substance on Ru (0 0 0 1) surface is at roughly 125°C, the low decomposition temperature observed is attributed to the Ru substrate.
- Published
- 2003
47. Green synthesis of CuO nanoparticles using Cassia auriculata leaf extract and in vitro evaluation of their biocompatibility with rheumatoid arthritis macrophages (RAW 264.7)
- Author
-
Pei-Fu Tang, Wei Zhang, Long-Bao Shi, Hao Zhang, Zhao Yanpeng, and Licheng Zhang
- Subjects
Biocompatibility ,biology ,Chemistry ,Scanning electron microscope ,Stereochemistry ,technology, industry, and agriculture ,Pharmaceutical Science ,Infrared spectroscopy ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Dynamic light scattering ,Transmission electron microscopy ,Cassia ,Pharmacology (medical) ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nuclear chemistry - Abstract
Purpose: To undertake green synthesis of copper oxide nanoparticles (CuO NPs) using Cassia auriculata leaf extract and evaluate their biocompatibility with rheumatoid arthritis macrophages (RAW 264.7 cell line). Methods: CuO NPs were prepared by heating a mixture of 10 mL of 0.01 M CuSO 4 solution and 30 mL of C. auriculata extract at 80 °C for 1 h. The synthesized CuO NPs were characterized by x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UVVis), energy-dispersive x-ray spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The cytotoxicity of the NPs against RAW 264.7 cells was studied using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: The gradual change in color of the reaction solution from brownish yellow to dark brown indicated CuO NP formation. TEM images revealed spherical, polydispersed NPs (mean particle size, 23 nm). FTIR results indicated capping of polyphenols on the surface of the NPs. Most RAW 264.7 cells (> 95 %) remained alive following exposure to CuO NPs at concentrations of up to 200 μg/mL, indicating biocompatible with the cells. Conclusion: An eco-friendly, low-cost, biosynthetic method for CuO NP preparation has been successfully developed using C. auriculata leaf extract. Furthermore, the nanoparticles are biocompatible with RAW 264.7 cell line. Keywords: Cassia auriculata extract, Copper oxide nanoparticles, RAW 264.7 cell line, Rheumatoid arthritis
- Published
- 2017
48. 3-Methylcholanthrene triggers the differentiation of alveolar tumor cells from canine bronchial basal cells and an altered p53 gene promotes their clonal expansion
- Author
-
Paul H. Gumerlock, Ank A.W. TenHave-Opbroek, and Xu-Bao Shi
- Subjects
Cancer Research ,Pathology ,medicine.medical_specialty ,biology ,Tumor suppressor gene ,Cellular differentiation ,Cell ,General Medicine ,Staining ,Proliferating cell nuclear antigen ,Basal (phylogenetics) ,chemistry.chemical_compound ,medicine.anatomical_structure ,chemistry ,Methylcholanthrene ,medicine ,biology.protein ,Progenitor cell - Abstract
Alveolar type II cells arising in canine bronchial autografts following exposure to 3-methylcholanthrene (MCA) give rise to carcinomas of varying glandular and squamous growth patterns. To study the role of the tumor suppressor gene p53 in this process, sections from progressive lesions were immunostained for p53 protein; microdissected regions were screened for p53 mutations. Adjacent sections were examined for type II cell expression [cuboid cell shape, large roundish nucleus, cytoplasmic staining for surfactant protein A (SP-A)] and proliferating cell nuclear antigen expression. Evidence for an altered p53 function (nuclear staining, missense mutations) was found in most carcinomas of all histologic types and in all grades of bronchial dysplasia, but not in hyperplastic or normal bronchial epithelium. It was primarily associated with the hyperplastic type II cell populations present in the basal zone of the lesions. In addition, we found SP-A staining in hyperplastic (but not in normal) bronchial basal cells. These data suggest that MCA initiates type II cell differentiation through phenotypic selection (basal cells). Inactivation of the p53 gene promotes the clonal expansion of the type II cells into discernible populations of (squamous or glandular) alveolar tumor cells. This in vivo study is the first to show that p53 is involved in a specific pathway leading to bronchogenic carcinoma.
- Published
- 2000
49. Efficient Recombination of Lym-1 scFv Gene Using Multiple Doubly-Restricted DNA Fragments
- Author
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Gerald L. DeNardo, Linda A. Kroger, Sally J. DeNardo, Paul H. Gumerlock, and Xu Bao Shi
- Subjects
Cancer Research ,DNA, Recombinant ,chemical and pharmacologic phenomena ,Regulatory Sequences, Nucleic Acid ,Deoxyribonuclease EcoRI ,Restriction fragment ,law.invention ,Gene product ,Antibodies, Monoclonal, Murine-Derived ,chemistry.chemical_compound ,law ,Gene expression ,Genes, Synthetic ,Humans ,Radiology, Nuclear Medicine and imaging ,Deoxyribonucleases, Type II Site-Specific ,Promoter Regions, Genetic ,Gene ,Polymerase chain reaction ,Electrophoresis, Agar Gel ,Pharmacology ,Expression vector ,Genes, Immunoglobulin ,biology ,Antibodies, Monoclonal ,General Medicine ,respiratory system ,Molecular biology ,Oncology ,chemistry ,biology.protein ,Recombinant DNA ,Immunoglobulin Light Chains ,Immunoglobulin Heavy Chains ,DNA - Abstract
In order to improve radioimmunotherapy of lymphoma, a Lym-1 single-chain antigen-binding (scFv) protein molecule was produced. Because the commonly used polymerase chain reaction (PCR) method frequently causes unexpected mutations, we developed a non-PCR method for scFv gene assembly. The method involved a stepwise linkage of doubly-restricted DNA fragments and re-digestion of the resultant concatamers. Using this strategy, the Lym-1 scFv expression gene was readily constructed without mutations. The recombinant gene was cloned into an expression vector and scFv protein was expressed. The method can be used for other genes or DNA recombination.
- Published
- 1999
50. Identification of p53 Mutations in Archival Prostate Tumors
- Author
-
Paul H. Gumerlock, Sara M. Bodner, Xu Bao Shi, and Ralph W deVere White
- Subjects
Male ,DNA Mutational Analysis ,Mutant ,Polymerase Chain Reaction ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Prostate cancer ,Prostate ,Tumor Cells, Cultured ,medicine ,Humans ,Molecular Biology ,Polymorphism, Single-Stranded Conformational ,Polymerase ,biology ,Prostatic Neoplasms ,Single-strand conformation polymorphism ,DNA, Neoplasm ,Cell Biology ,Genes, p53 ,medicine.disease ,Molecular biology ,DNA Repair Enzymes ,Exodeoxyribonucleases ,medicine.anatomical_structure ,chemistry ,Mutation ,biology.protein ,Mutation testing ,Nested polymerase chain reaction ,DNA - Abstract
To correlate molecular changes with clinical information in prostate tissue, it is necessary to have accurate methods for screening for mutations in clinically available specimens. We have refined the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis for detection of p53 mutations in routine pathology specimens. These improvements help overcome technical barriers that interfere with SSCP analysis of archival tissues when only small amounts of poorly preserved formalin-fixed DNA are available. Furthermore, prostate samples are heterogeneous in containing tumor, normal tissue, and hyperplastic tissue. To address the first issue, the method included an initial selection of PCR products using exonuclease I, followed by a second-step selection using nested PCR. This step ensures adequate amplification of the target sequence while minimizing artifactual products that could otherwise interfere with mutation analysis. For the second issue, in addition to morphologic selection of appropriate tissue areas, we improved the sensitivity of detection of mutations by using restriction enzyme digestion of products prior to SSCP analysis. Detection of mutations in heterogeneous tissue was evaluated by determining the minimal detectable mutant allele frequencies in exons 4, 5, 6, 7, 8-9, and 10 by using mixtures of known mutant and wild-type cell lines, which were found to be 17.6, 9.1, 12.5, 8.1 14.0, and 14.3%, respectively. To determine the utility of this method when used on heterogeneous clinical samples, we performed study of 19 archival prostate specimens (14 primary prostate cancers, three benign prostatic hyperplasia and two metastases) and detected abnormally migrating products in six of the prostate cancer specimens (four primaries and two metastases). In five of these samples, there was sufficient DNA to perform sequencing, which disclosed single-base change mutations in all five samples.
- Published
- 1996
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