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Ma DM, Han LQ, Bai JJ, Li SJ, Fan JJ, Yu LY, Quan YC. A 66-bp deletion ingrowth hormone releasing hormonegene 5′-flanking region with largemouth bass recessive embryonic lethal. Anim Genet 2014; 45:421-6. [DOI: 10.1111/age.12143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2014] [Indexed: 11/30/2022]
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102
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Yang WC, Li SJ, Chen L, Yang LG. FSHR genotype affects estrogen levels but not pregnancy rates in Luxi cattle subjected to embryo transfer. GENETICS AND MOLECULAR RESEARCH 2014; 13:1563-9. [PMID: 24668630 DOI: 10.4238/2014.march.12.8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Follicle-stimulating hormone receptor (FSHR), which mediates the functioning of FSH, plays a central role in reproduction. We investigated bovine FSHR gene polymorphisms and analyzed their relationships with pregnancy rates after embryo transfer and with hormone concentrations on the day of embryo transfer. One reported SNP of FSHR, G-278A, located in the 5'-upstream region, was analyzed and three genotypes (GG, GA and AA) were detected in 132 Luxi cattle recipients. Statistical analysis revealed that recipients with the GG genotype had significantly higher estrogen levels on the day of embryo transfer than did GA and AA genotypes. There were no significant differences in pregnancy rates among genotypes, after embryo transfer. We conclude that variation at these loci of the FSHR gene has no significant effect on pregnancy rates in Luxi cattle.
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103
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Zhu YD, Tan ML, Li SJ, Qiu SC. [Lateral supramalleolar artery descending branch antidromic flap for the repair of soft tissue defects in the foot and ankle]. ZHONGGUO GU SHANG = CHINA JOURNAL OF ORTHOPAEDICS AND TRAUMATOLOGY 2014; 27:258-260. [PMID: 24974435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To evaluate the effect of lateral supramalleolar artery descending branch antidromic flap for the repair of soft tissue defects in the foot and ankle. METHODS From May 2009 to October 2013,12 patients with soft tissue defects combined with tendon and bone exposure in the foot and ankle were treated by lateral supramalleolar artery descending branch antidromic flap for the repair of soft tissue defects in the foot and ankle, including 9 males and 3 females with an average age of 37.5 years old ranging from 19 to 58 years. Ten cases had the soft tissue defects in the dorsum of foot and 2 in the ankle. The defect area of soft tissue was from 11 cm x 9 cm to 8 cm x 5 cm. RESULTS Twelve patients were follow-up for 3 to 12 months (averaged 7.3 months). The flaps of 9 cases were survived,the flaps edges of the other 3 cases were necrosis,and healed after dressing change. The flaps were slightly swelling without ulcer occurrence. CONCLUSION Lateral supramalleolar artery descending branch antidromic flap can repairing the damage by one-stage operation with advantage of dissection easy,rich blood supply without sacrifice of major artery.
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104
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Jiang GQ, Li SJ, Zhang YQ, Zhang QJ. Structure and magnetic properties of A Cu(II) coordination polymer supported by a tetrapodal Schiff base ligand. INORG CHEM COMMUN 2014. [DOI: 10.1016/j.inoche.2013.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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105
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Yang WC, Li SJ, Chen L, Yang LG. Polymorphism of the inhibin βA gene and its relationship with superovulation traits in Chinese Holstein cows. GENETICS AND MOLECULAR RESEARCH 2014; 13:269-75. [PMID: 24535853 DOI: 10.4238/2014.january.17.11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Inhibin is a major regulator of secretion of follicle-stimulating hormone, which is involved in follicular development and regulation of steroidogenesis in females. The objectives of this study were to detect polymorphisms of the bovine inhibin beta-A subunit (INHβA) gene and to evaluate its associations with superovulatory responses in 171 Chinese Holstein cows treated for superovulation. Polymerase chain reaction-restricted fragment length polymorphism revealed a C>T transition determining the StyI polymorphism at position 7639 in intron I of the bovine INHβA gene, and three genotypes (CC, CT, and TT) were detected. The frequencies of the three genotypes showed a tendency for CT > TT > CC, and this polymorphism was in Hardy-Weinberg equilibrium. Statistical analysis revealed no significant differences of least square means for superovulation traits among the three genotypes (P > 0.05). These results demonstrate, for the first time, that the detected loci of the INHβA gene have no significant effects on superovulation performance in Chinese Holstein cows.
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Su XL, Wang YF, Li SJ, Zhang F, Cui HW. High methylation of the SEPT9 gene in Chinese colorectal cancer patients. GENETICS AND MOLECULAR RESEARCH 2014; 13:2513-20. [PMID: 24535900 DOI: 10.4238/2014.january.17.5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Methylation of the septin 9 gene (SEPT9) occurs in higher frequency in colorectal cancer (CRC) compared to control samples, which suggests that SEPT9 methylation is a useful biomarker for screening CRC. However, the methylation status of SEPT9 in Chinese CRC patients is scarcely reported. In the present study, SEPT9 methylation was tested in CRC tissues obtained from a Chinese population and correlations with pathological characteristics were investigated. The methylation status of SEPT9 was detected using methylation-specific polymerase chain reaction (PCR)-denaturing high-performance liquid chromatography (MSP-DHPLC) in 234 colorectal tissues (172 cases, 62 controls). Samples were sequenced to confirm the results from MSP-DHPLC. The chi-squared test was used to analyze the correlation of SEPT9 gene methylation status and pathological characteristics in CRCs. SEPT9 gene methylation was detected in 152 of 172 (88.4%) cases of verified CRC and in 4 of 62 (6.5%) healthy controls (χ(2) = 137.62, P < 0.001). There was no association between the methylation status of SEPT9 and age, gender, Duke's stage, TNM stage, differentiation, and site of cancer (P > 0.05). Our results suggest that SEPT9 gene methylation is a valuable biomarker for screening CRC in the Chinese population.
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Li SJ, Yao ZA. Image inpainting algorithm based on partial differential equation technique. THE IMAGING SCIENCE JOURNAL 2013. [DOI: 10.1179/1743131x11y.0000000055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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108
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Han JJ, Bao L, He LW, Zhang XQ, Yang XL, Li SJ, Yao YJ, Liu HW. Phaeolschidins A-E, five hispidin derivatives with antioxidant activity from the fruiting body of Phaeolus schweinitzii collected in the Tibetan Plateau. JOURNAL OF NATURAL PRODUCTS 2013; 76:1448-1453. [PMID: 23869482 DOI: 10.1021/np400234u] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Five new hispidin derivatives, phaeolschidins A-E (1-5), as well as two known natural products, pinillidine (6) and hispidin (7), were isolated from the fruiting bodies of Phaeolus schweinitzii collected in the Tibetan Plateau. The structures of the new compounds were elucidated by spectroscopic methods. Phaeolschidins A-D (1-4) are new bishispidins. Phaeolschidin E (5) is a new class of hispidin derivative in which one pyrrolidin-2-one moiety was linked to C-3 of hispidin. The antioxidant activity of 1-7 was evaluated using three methods: the DPPH scavenging assay, the total antioxidant capacity assay, and the lipid peroxidation assay. Hispidin showed the strongest antioxidant activity of all tested compounds. This is the first report of secondary metabolites from the fungus P. schweinitzii.
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Yang Y, Gong P, Feng YP, Li SJ, Peng XL, Ran ZP, Qian YG, Gong YZ. Temporospatial expression of Dmrt1 in chicken urogenital system (Gallus gallus) using whole mount in situ hybridization. ACTA BIOLOGICA HUNGARICA 2013; 64:161-8. [PMID: 23739885 DOI: 10.1556/abiol.64.2013.2.3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Doublesex and mab-3-related transcription factor 1 (Dmrt1) is a Z-linked gene that putatively determines the phenotype of gonads in birds. The sex differential expression of Dmrt1 was examined using wholemount in situ hybridization (WISH) in the urogenital systems during embryogenesis. The results revealed that Dmrt1 showed dimorphic expression in chicken gonads, which increased from day 6.5 to day 10.5. The expression of Dmrt1 in male (ZZ) gonads was not twice as much as in female (ZW) gonads, suggesting the existence of other regulatory mechanisms in addition to Z chromosome dosage effect.
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Osselaere A, Li SJ, De Bock L, Devreese M, Goossens J, Vandenbroucke V, Van Bocxlaer J, Boussery K, Pasmans F, Martel A, De Backer P, Croubels S. Toxic effects of dietary exposure to T-2 toxin on intestinal and hepatic biotransformation enzymes and drug transporter systems in broiler chickens. Food Chem Toxicol 2013; 55:150-5. [PMID: 23313610 DOI: 10.1016/j.fct.2012.12.055] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 12/21/2012] [Accepted: 12/31/2012] [Indexed: 01/06/2023]
Abstract
The effects of the mycotoxin T-2 on hepatic and intestinal drug-metabolizing enzymes (cytochrome P450) and drug transporter systems (MDR1 and MRP2) in poultry were investigated during this study. Broiler chickens received either uncontaminated feed, feed contaminated with 68μg/kg or 752μg/kg T-2 toxin. After 3weeks, the animals were euthanized and MDR1, MRP2, CYP1A4, CYP1A5 and CYP3A37 mRNA expression were analyzed using qRT-PCR. Along the entire length of the small intestine no significant differences were observed. In the liver, genes coding for CYP1A4, CYP1A5 and CYP3A37 were significantly down-regulated in the group exposed to 752μg/kg T-2. For CYP1A4, even a contamination level of 68μg/kg T-2 caused a significant decrease in mRNA expression. Expression of MDR1 was not significantly decreased in the liver. In contrast, hepatic MRP2 expression was significantly down-regulated after exposure to 752μg/kg T-2. Hepatic and intestinal microsomes were prepared to test the enzymatic activity of CYP3A. In the ileum and liver CYP3A activity was significantly increased in the group receiving 752μg/kg T-2 compared to the control group. The results of this study show that drug metabolizing enzymes and drug transporter mechanisms can be influenced due to prolonged exposure to relevant doses of T-2.
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111
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Zhang F, Zeng YL, Zhang XG, Chen WJ, Yang R, Li SJ. RNA interference targeting extracellular matrix metalloproteinase inducer (CD147) inhibits growth and increases chemosensitivity in human cervical cancer cells. EUR J GYNAECOL ONCOL 2013; 34:429-435. [PMID: 24475577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Overexpression of extracellular matrix metalloproteinase (MMP) inducer (EMMPRIN CD147) has been implicated in the growth and survival of malignant cells. However, its presence and role in cervical cancer cells has not been well-studied. In the present study, small interfering RNA (siRNA) was designed and synthesized to breakdown the expression of CD147. The present data demonstrated that 24 and 48 hours after transfecting CD147 siRNA, both the CD147 mRNA and protein expression were significantly inhibited as determined by quantitative real-time polymerase chain reaction (RT-PCR) and immunocytochemistry. Meanwhile, simultaneous silencing of CD147 resulted in distinctly increasing MMP-9, VEGF, and MDR-1. Further studies demonstrated decreased CD147 expression, resulted in G1/S phase transition with flow cytometry analysis, as well as the resistance of the cells to 5-FU. These findings provide further evidence that CD147 may become a promising therapeutic target for human cervical cancer and a potential chemotherapy-sensitizing agent.
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Gong P, Yang YP, Yang Y, Feng YP, Li SJ, Peng XL, Gong YZ. Different gene transfer methods at the very early, early, late and whole embryonic stages in chicken. ACTA BIOLOGICA HUNGARICA 2012; 63:453-62. [PMID: 23134602 DOI: 10.1556/abiol.63.2012.4.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
New technologies in gene transfer combined with experimental embryology make the chicken embryo an excellent model system for gene function studies. The techniques of in ovo electroporation, in vitro culture for ex ovo electroporation and retrovirus-mediated gene transfer have already been fully developed in chicken. Yet to our knowledge, there are no definite descriptions on the features and application scopes of these techniques. The survival rates of different in vitro culture methods were compared and the EGFP expression areas of different gene transfer techniques were explored. It was that the optimal timings of removing embryo for EC culture and Petri dish system was at E1.5 and E2.5, respectively; and optimal timing of injecting retrovirus is at E0. Results indicated that the EC culture, in ovo electroporation, the Petri dish system and retrovirus-mediated method are, respectively, suitable for the very early, early, late and whole embryonic stages in chicken. Comparison of different gene transfer methods and establishment of optimal timings are expected to provide a better choice of the efficient method for a particular experiment.
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Wang HB, Li SJ, Xiu SL, Gong L, Chen G, Mizuseki H, Kawazoe Y. Insight into the vertical detachment energy oscillation of Na(n)C60(-) clusters. J Chem Phys 2012; 136:174314. [PMID: 22583237 DOI: 10.1063/1.4712219] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We have performed a detailed density functional theory study on the structural and electronic properties of Na(n)C(60)(-) (n = 1-12) clusters. The calculated vertical detachment energies show good agreement with the experimental data, which confirms the 3p (n = 3p) oscillation rule. The oscillation can be attributed to the combination of the charge depletion distribution induced by removing electrons and the number of the sodium atoms in direct contact with the fullerene. Based on the structural and electronic properties, the Na atoms can be categorized into two groups, one is for the metal atoms directly bonded to the fullerene surface, and the other one is for those without bonding to the fullerene. The Na atoms in group one would donate electrons to both the fullerene and the Na atoms in group two. As the total number of the sodium atoms increases, the number of Na atoms in group one would continue increasing till the size n = 3p - 1 to meet a shoulder from n = 3p - 1 to n = 3p, which accounts for the maximum vertical detachment energy at the size of n = 3p as drawn from the detailed electronic property studies.
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Zhang N, Chen TH, Zhou YF, Li SJ, Jin J, Wang YM. [Experimental study on acid mine drainage treatment using mine tailings of Xiangsi Valley, Tongling, China]. HUAN JING KE XUE= HUANJING KEXUE 2012; 33:1272-1277. [PMID: 22720577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Mine tailings in Xiangsi Valley, Tongling, China, is a typical skarn-type tailing with high contents of carbonates. This study designed dynamic leaching experiments to investigate the efficiency of this tailing under the acid mine drainage treatment. During 80 d trial period, the physical and chemical properties of influents were fixed and the effluents were monitored. After the trial, the speciation of Fe, Cu and Zn in solid was analyzed. The results showed that during the trial period, pH value maintained above 7.5. Moreover, the concentrations of Cu, Zn, Fe ions in effluents kept below 0.1, 0.4 and 1 mg x L(-1), respectively. In addition, the permeability coefficient of experimental column kept decreasing during the experimental period (from 0.23 cm x s(-1) to 0.10 cm x s(-1)). Five-step sequential extraction method was employed to study the distribution of elements at different depths. The results showed that Cu2+, Zn2+ were removed mainly through sorption and precipitation. This study indicates that Tongling skarn mine tailings have strong acid neutralization as well as heavy metal binding capacities. Therefore, the authors suggest that this mine tailing, which used to be waste, has a potential in AMD control and treatment.
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Li SJ, Chen TH, Zhou YF, Yue ZB, Jin J, Liu C. [Effect of Zn(II) on microbial activity in anaerobic acid mine drainage treatment system with biomass as carbon source]. HUAN JING KE XUE= HUANJING KEXUE 2012; 33:293-298. [PMID: 22452225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this study, with rape straw as carbon source, anaerobic batch experiments were executed to investigate the effect of Zn (II) on the activity of sulphate reducing bacteria (SRB) in the microbial treatment of simulative acid mine drainage (AMD). The results showed that during the 60 experimental days, when initial Zn2+ concentrations were in the range of 73.7 to 196.8 mg x L(-1), SRB had high culturalbility. At the end of these experiments, pH values rose from initial 5.0 to neutral, about 96% of sulphate was reduced and the concentrations of Zn2+ reduced to 0.05 mg x L(-1). The results of Tessier sequential extraction, field emission scanning electron microscope (FE-SEM) and X-ray diffraction(XRD) showed that Zn was found to be fixed through forming organic and sulphide (mainly sphalerite) compounds. For the experiment with high Zn2+ concentration (262.97 mg x L(-1)), at the end of experiments, pH values dropped from initial 5.0 to 4.0, only 27% of sulphate was only reduced and the concentrations of Zn2+ kept in high range (25 mg x L(-1)), the activity of SRB significantly inhibited. This study indicated that: (1) Rape straw can be used as slow-release carbon source for long-term anaerobic AMD treatment; (2) Rape straw can decrease the toxicity of Zn2+ to SRB through adsorption; (3) In anaerobic AMD treatment system, Zn can be fixed by sulphide minerals with mediation of SRB.
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116
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Hou XH, Li DJ, Su H, Hu JQ, Li N, Li SJ. Molecular cloning, expression, and imprinting status of maternally expressed gene 8 (Meg8) in dairy cattle. GENETIKA 2011; 47:1120-1125. [PMID: 21954621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
At present, small number imprinted genes have been reported in cattle compare to human and mouse. Maternally expressed gene 8 (Meg8), a non-coding gene, have been identified maternally expressed in mouse and sheep, but its sequences and imprinting status have not been established in cattle. In this study, the full-length of cattle Meg8cDNA sequence was obtained by reverse transcript polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) method, which has a high homology in exons sequences with the corresponding region of sheep Meg8. The isolation of cDNA sequence showed the presence of multiple splice variants in cattle Meg8 gene. The Meg8 was found to be expressed in all adult examined tissues, including heart, liver, spleen, lung, kidney, brain, subcutaneous fat and skeletal muscle. A single nucleotide polymorphism (SNP) was identified in exon 6 by Single-Strand Conformation Polymorphism (SSCP), and used to distinguish between monoallelic and biallelic expression in cattle tissues. The expression analysis of Meg8 in a heterozygous cattle showed that only one parental allele was expressed in all examined tissues, suggesting that Meg8 is imprinted in cattle.
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117
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Yang WC, Tang KQ, Li SJ, Yang LG. Association analysis between variants in bovine progesterone receptor gene and superovulation traits in Chinese Holstein cows. Reprod Domest Anim 2011; 46:1029-34. [PMID: 21426415 DOI: 10.1111/j.1439-0531.2011.01780.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The objective of this study was to identify a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism. The PCR-RFLP method was applied to detect two reported single nucleotide polymorphisms (SNPs) of G59752C and T81637C (rs41614030) located in introns 3 and 4 of the bovine progesterone receptor (PGR) gene in 171 Chinese Holstein cows treated for superovulation and evaluate its associations with superovulation traits. In polymorphic locus 81637, all cows without superovulation response were g.81637TC and g.81637TT genotypes. Association analysis showed that these two SNPs had significant effects on the total number of ova (TNO) (p<0.05), and the T81637C polymorphism was significantly associated with the number of transferable embryos (p<0.05). In addition, significant additive effects (p<0.05) on TNO were detected in the polymorphisms of G59752C and T81637C. These results showed for the first time that the G59752C and T81637C polymorphisms in PGR gene were associated with superovulation traits and indicated that PGR gene can be used as a predictor for superovulation in Chinese Holstein cows.
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118
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Ou Q, Li SJ, Cheng XJ. Cerebral sparganosis: A case report. Biosci Trends 2010; 4:145-147. [PMID: 20592465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Sparganosis is a rare parasitic infection in humans caused by a larval cestode of the genus Spirometra. Spargana invade muscle, subcutaneous tissue, the eye, urogenital, and abdominal viscera, but the central nervous system (CNS) is not a frequent site of invasion. Here, we describe an 18-year-old patient with cerebral sparganosis and review data from other cases reported in the medical literature.
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119
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Wu CJ, Chiu KM, Chu SH, Li SJ. Bullet embolisation from the right subclavian vein to the right ventricle: a case report. Emerg Med J 2009; 26:839. [DOI: 10.1136/emj.2008.067900] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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120
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Chen MF, You C, Li SJ, Yang R, Guo ZX. The formation of nanocrystallite bone-like apatite on chemically treated Ti-24Nd-4Zr-7.9Sn alloy. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1214-1217. [PMID: 19441490 DOI: 10.1166/jnn.2009.c122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ti-24Nd-4Zr-7.9Sn alloy with low elastic modulus and high strength is a great candidate for artificial biomaterials used in orthopedic and dental implants. In order to improve biocompatibility, a biomimetic process was employed to deposit a bone-like apatite nanocrystal coating on alloy. Analysis of the coatings showed that a net-like Na2TiO3 layer with about 100 nm in size was formed on Ti-24Nd-4Zr-7.9Sn treated by NaOH. Consequently, a carbonated apatite nanocrystal coating, namely bone-like apatite, was biomimetically deposited on Na2TiO3 layer, which has similar mineral composition to that of natural bone. The growth mechanism of bone-like layer is also discussed.
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Cui JP, Hao YL, Li SJ, Sui ML, Li DX, Yang R. Reversible movement of homogenously nucleated dislocations in a beta-titanium alloy. PHYSICAL REVIEW LETTERS 2009; 102:045503. [PMID: 19257440 DOI: 10.1103/physrevlett.102.045503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Indexed: 05/27/2023]
Abstract
We demonstrate reversible movement of 1/2[11[over ]0](110) dislocation loops generated from nanodisturbances in a beta-titanium alloy. High resolution transmission electron microscope observations during an in situ tensile test found three reversible deformation mechanisms, nanodisturbances, dislocation loops and martensitic transformation, that are triggered in turn with increasing applied stress. All three mechanisms contribute to the nonlinear elasticity of the alloy. The experiments also revealed the evolution of the dislocation loops to disclination dipoles that cause severe local lattice rotations.
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Feng DQ, Ke CH, Lu CY, Li SJ. Herbal plants as a promising source of natural antifoulants: evidence from barnacle settlement inhibition. BIOFOULING 2009; 25:181-190. [PMID: 19169950 DOI: 10.1080/08927010802669210] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A series comprising hexane, ethyl acetate, ethanol and aqueous extracts from six common Chinese herbs (Carpesium abrotanoides, Melia toosendan, Cnidium monnieri, Vitex negundo, Stemona sp. and Sophora flavescens) was investigated for antifouling (AF) activity against cypris (cyprids) larvae of the barnacle Balanus albicostatus. All extracts tested except the aqueous extract from Stemona sp. significantly inhibited the settlement of cyprids, the most potent being the ethyl acetate extract of S. flavescens (EC(50) value 2.08 microg ml(-1)), from which an AF compound, identified as 2'-methoxykurarinone, was isolated using bioassay-guided procedures. Furthermore, the AF activity of this compound was found to be highly reversible and greater than that of the three other natural products from S. flavescens, namely matrine, oxymatrine and oxysophocarpine. These compounds have been used commercially in China for their pharmaceutical activities, but their AF activities have not previously been evaluated. Analysis of structure-activity relationships suggested that the N-1 nitrogen atom in matrine plays a crucial role in AF activity. Overall, the present findings indicate that herbal plants are a valuable source of novel AF agents.
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Hao YL, Li SJ, Sun BB, Sui ML, Yang R. Ductile titanium alloy with low Poisson's ratio. PHYSICAL REVIEW LETTERS 2007; 98:216405. [PMID: 17677794 DOI: 10.1103/physrevlett.98.216405] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2007] [Indexed: 05/16/2023]
Abstract
We report a ductile beta-type titanium alloy with body-centered cubic (bcc) crystal structure having a low Poisson's ratio of 0.14. The almost identical ultralow bulk and shear moduli of approximately 24 GPa combined with an ultrahigh strength of approximately 0.9 GPa contribute to easy crystal distortion due to much-weakened chemical bonding of atoms in the crystal, leading to significant elastic softening in tension and elastic hardening in compression. The peculiar elastic and plastic deformation behaviors of the alloy are interpreted as a result of approaching the elastic limit of the bcc crystal under applied stress.
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Hao YL, Li SJ, Sun SY, Zheng CY, Yang R. Elastic deformation behaviour of Ti-24Nb-4Zr-7.9Sn for biomedical applications. Acta Biomater 2007; 3:277-86. [PMID: 17234466 DOI: 10.1016/j.actbio.2006.11.002] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 11/02/2006] [Accepted: 11/07/2006] [Indexed: 11/25/2022]
Abstract
In this paper, the elastic deformation behaviour of a recently developed beta-type titanium alloy Ti-24Nb-4Zr-7.9Sn (wt.%) that consists of non-toxic elements and is intended for biomedical applications is described. Tensile tests show that this alloy in the as hot-rolled state exhibits peculiar non-linear elastic behaviour with maximum recoverable strain up to 3.3% and incipient Young's modulus of 42GPa. Solution treatment at high temperature has trivial effect on super-elasticity but decreases strength and slightly increases the incipient Young's modulus. Ageing treatment in the (alpha+beta) two-phase field increases both strength and Young's modulus and results in a combination of high strength and relatively low elastic modulus. In spite of the formation of the alpha phase, short time ageing has no effect on super-elasticity, whereas the non-linear elastic behaviour transforms gradually to normal linear elasticity with the increase of ageing time. We suggest sluggish, partially reversible processes of stress-induced phase transformation and/or incipient kink bands as the origin of the above peculiar elastic behaviour.
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Li SJ, Deng XM, Mao HZ, Hong Y. Enhanced anthocyanin synthesis in foliage plant Caladium bicolor. PLANT CELL REPORTS 2005; 23:716-720. [PMID: 15372198 DOI: 10.1007/s00299-004-0871-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Revised: 08/04/2004] [Accepted: 08/05/2004] [Indexed: 05/24/2023]
Abstract
A protocol was developed for Agrobacterium-mediated genetic transformation of monocotyledon foliage plant Caladium bicolor cv. Jackie Suthers using leaf disc and petiole as the explants. The explants were inoculated with Agrobacterium strain LBA4404 harboring a binary vector with the maize anthocyanin regulatory gene Lc under the control of the cauliflower mosaic virus promoter. Callus formation was induced in MS medium supplemented with 0.5 mg/l 6-benzylaminopurine (6-BA), 0.1 mg/1 2,4-dichlorophenoxyacetic acid (2,4-D), 30 g/l sucrose and kanamycin 50 mg/l for selection. Resistant calli were induced for shoot generation in MS medium with 2 mg/l 6-BA and 0.2 mg/l alpha-naphthaleneacetic acid. As much as 10% of the explants gave rise to kanamycin-resistant shoots with our procedure. Transformed plants had enhanced anthocyanin accumulation in the roots, leaves and stems (epidermis and vascular bundles). Integration of the transgene into the host genome was confirmed by genomic Southern blot hybridization, and RNA blot hybridization analysis indicated that the expression of the transgene correlated with anthocyanin accumulation. This investigation illustrates the utility of anthocyanin regulatory genes in the genetic manipulation of the color of foliage plants. It also supports the premise that the Lc gene can be used as a powerful non-destructive cell autonomous visual marker in a wide variety of plants, as exemplified by the perfect symmetrical half-green/half-red plant presumably derived from the symmetrical division of one transgenic and one non-transgenic precursor meristematic cell.
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