The growth and development of skeletal muscle also determine the meat production of yak, ultimately affecting the economic benefits. Hence, improving growth performance is a top priority in the yak industry. Skeletal ...The growth and development of skeletal muscle also determine the meat production of yak, ultimately affecting the economic benefits. Hence, improving growth performance is a top priority in the yak industry. Skeletal muscle development is a complex process involving the regulation of several genes, including microRNAs(miRNAs). However,the transcription of miRNAs in yak skeletal muscle during prenatal to postnatal stages is unknown. We used small RNA sequencing(small RNA-Seq) to determine the global miRNAs of longissimus dorsi muscle from yak(the samples were collected from three fetuses and three adults). Totally 264 differently expressed miRNAs(|log2(fold change)|>1and P-value≤0.05) were detected between the two groups. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analysis showed that differently expressed miRNAs-targeted genes participated in pathways associated with muscle development, such as MAPK, PI3K-Akt, and Hippo signaling pathways, etc. MiR-652, which was up-regulated in the fetal group, was transfected into C2C12 myoblasts to examine its role. miR-652 promoted(P≤0.05)proliferation and differentiation, but inhibited(P≤0.001) apoptosis at early period. Furthermore, miR-652 reduced(P≤0.001) the proportion of C2C12 myoblasts in the G1 phase while increasing(P≤0.01) the proportion of cells in the S and G2 phases. Dual-luciferase reporter assays indicated that ISL1 served as a target of miR-652. In general, these findings expand our understanding of yak skeletal muscle miRNAs, and suggested that miR-652 probably regulated myogenesis by regulating ISL1.展开更多
目的 探讨乳腺癌患者血清核受体亚家族C组成员2(nuclear receptor subfamily 3, group C, member 2,NR3C2),DNA甲基化转移酶-3A[DNA(cytosine-5)-methyltransferase 3A,DNMT3A]水平及其临床诊断价值。方法收集复旦大学附属华东医院2017...目的 探讨乳腺癌患者血清核受体亚家族C组成员2(nuclear receptor subfamily 3, group C, member 2,NR3C2),DNA甲基化转移酶-3A[DNA(cytosine-5)-methyltransferase 3A,DNMT3A]水平及其临床诊断价值。方法收集复旦大学附属华东医院2017年5月~2020年12月期间住院的94例乳腺癌患者为乳腺癌组,另选取同期健康体检者86例作为对照组。酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测两组血清NR3C2和DNMT3A水平,Pearson法分析乳腺癌患者血清NR3C2和DNMT3A表达水平相关性,多因素Logistic回归分析乳腺癌发生的影响因素,受试者工作特征(receiver operating characteristic,ROC)曲线评估NR3C2和DNMT3A对乳腺癌的诊断价值。结果 乳腺癌组患者血清NR3C2水平为317.84±33.47 ng/L,低于对照组(374.25±47.72ng/L),DNMT3A的表达水平为451.63±75.47μg/L,高于对照组(349.85±63.72μg/L),差异有统计学意义(t=9.243,9.729,均P<0.05)。Pearson分析结果显示,乳腺癌患者血清NR3C2与DNMT3A表达水平存在明显负相关(r=-0.501,P=0.000)。Logistic回归分析结果显示,NR3C2高水平为乳腺癌发生的保护因素(OR=0.563,95%CI:0.372~0.851,P=0.006),DNMT3A高水平是乳腺癌发生的危险因素(OR=1.834,95%CI:1.249~2.693,P=0.002)。ROC曲线结果发现,血清NR3C2与DNMT3A诊断乳腺癌的曲线下面积(area under the curve,AUC)分别为0.853(0.791~0.915),0.930(0.896~0.965),当两者联合时其AUC为0.969(0.949~0.990),高于两者单独检测(Z=3.460,1.894,P=0.000,0.034)。结论 乳腺癌患者血清NR3C2表达水平降低,DNMT3A表达水平升高,两者联合检测能够提高乳腺癌的诊断价值。展开更多
AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (D...AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells.展开更多
Let Y be a closed 3-manifold such that all flat SU(2)-connections on Y are non-degenerate.In this article,we prove a Uhlenbeck-type compactness theorem on Y for stable flat SL(2,C)connections satisfying an L^(2)-bound...Let Y be a closed 3-manifold such that all flat SU(2)-connections on Y are non-degenerate.In this article,we prove a Uhlenbeck-type compactness theorem on Y for stable flat SL(2,C)connections satisfying an L^(2)-bound for the real curvature.Combining the compactness theorem and a result from[7],we prove that the moduli space of the stable flat SL(2,C)connections is disconnected under certain technical assumptions.展开更多
The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160～163), is re-described in the centric P21/c space g...The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160～163), is re-described in the centric P21/c space group.展开更多
目的探讨核受体亚家族2c成员2(nuclear receptor subfamily 2 group C member 2,NR2C2)在泌乳素瘤的表达水平及其与临床特征的关系。方法采用免疫组化染色和蛋白印迹实验检测46例泌乳素瘤患者的肿瘤组织NR2C2表达水平。用RNA干扰技术敲...目的探讨核受体亚家族2c成员2(nuclear receptor subfamily 2 group C member 2,NR2C2)在泌乳素瘤的表达水平及其与临床特征的关系。方法采用免疫组化染色和蛋白印迹实验检测46例泌乳素瘤患者的肿瘤组织NR2C2表达水平。用RNA干扰技术敲低MMQ细胞NR2C2表达水平,行细胞增殖实验检测细胞活力,流式细胞仪检测细胞凋亡率。结果按照Knosp分级将患者分为侵袭组和非侵袭组。侵袭组NR2C2表达的免疫组化评分为148.2±42.7,非侵袭组为45.2±28.72;NR2C2表达水平与肿瘤大小成正相关(r=0.327,P=0.039);疏松颗粒型患者的表达水平更高(P=0.003)。蛋白印迹实验检测NR2C2蛋白水平,筛选出Sh-B(23.4%)和Sh-C(34%)片段;干扰24h、48h和72h后,与对照组相比Sh-B组的细胞活力分别下降24.8%、39.2%和48.3%,Sh-C组分别下降19.1%、26.4%和32.5%(均P<0.05)。干扰24h后,Sh-B组AnnexinV阳性细胞为(10.3±3.1)%,PI阳性细胞为(7.3±2.1)%;Sh-C组分别为(8.5±2.3)%和(5.6±1.8)%;均明显高于对照组(均P<0.05)。结论 NR2C2能促进肿瘤生长,与催乳素腺瘤的发生发展密切相关。展开更多
Chevkinite specimen from a rare-earth mineral deposit in Sichuan, southwest of China have been studied in detail by means of transmission electron microscope (TEM).The selected area electron diffraction (SAED)and conv...Chevkinite specimen from a rare-earth mineral deposit in Sichuan, southwest of China have been studied in detail by means of transmission electron microscope (TEM).The selected area electron diffraction (SAED)and convergent beam electron diffraction (CBED) patterns , obtained from different crystal zone axis direction , proved coincidently that the space group of chevkinite is C2/m . Fringe lattice image observation showed the mineral crystal is structurally uniform in microscale , and it is an ideal specimen for electron diffraction analysis . The mineral studied here is similar to the one from Bayan Obo , Inner Mongolia , China , in chemical composition and REE distribution . The chemical formula of the crystal is (Ce , La ,… , Ca) 4 Fe2+ (Fe, Ti, Nb) 2 O8 (Si2O7)2 From our study , we come to the conclusion that the space group of the natural chevkinite is C2/m , instead of P21/a as synthetic one . Up to now , chevkinite compositionally similar to the synthetic one , in which the complete replacements of Ce , La by Nd and Fe by Mg or Co occur , has not been discovered in nature . So we suggest that the name for synthesized chevkinite should be further discussed .展开更多
MXenes are a new type of two-dimensional carbides with rich physical and chemical properties. The physics of MXenes, and thus the applications, are dominated by surface functional groups. Herein, the effects of differ...MXenes are a new type of two-dimensional carbides with rich physical and chemical properties. The physics of MXenes, and thus the applications, are dominated by surface functional groups. Herein, the effects of different terminations(O,S, Se, Te) on the geometric and electronic properties of Nb_(2)C MXenes were studied via density functional theory(DFT)calculations. Three adsorption sites were examined to determine the most stable configurations. The results showed that both the types and the positions of surface functional groups influence the geometric stability and physical characters of Nb_(2)C. The S and Se terminations make the Nb_(2)C MXenes to be semiconductor, while Nb_(2)C MXenes with other terminations(O, Te) are conductor. The electron location function, density of states, Bader charge distribution, and the projected crystal orbital Hamilton population were conducted to explain the origin of adsorption stability and electronic nature difference. Our results provide a fundamental understanding about the effects of surface terminations on the intrinsic stability and electronic properties of Nb_(2)C MXenes.展开更多
基金supported by the Agricultural Science and Technology Innovation Program, CAAS (25-LZIHPS-01)the China Agriculture Research System of MOF and MARA (CARS-37)the National Natural Science Foundation of China (32102500)。
文摘The growth and development of skeletal muscle also determine the meat production of yak, ultimately affecting the economic benefits. Hence, improving growth performance is a top priority in the yak industry. Skeletal muscle development is a complex process involving the regulation of several genes, including microRNAs(miRNAs). However,the transcription of miRNAs in yak skeletal muscle during prenatal to postnatal stages is unknown. We used small RNA sequencing(small RNA-Seq) to determine the global miRNAs of longissimus dorsi muscle from yak(the samples were collected from three fetuses and three adults). Totally 264 differently expressed miRNAs(|log2(fold change)|>1and P-value≤0.05) were detected between the two groups. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analysis showed that differently expressed miRNAs-targeted genes participated in pathways associated with muscle development, such as MAPK, PI3K-Akt, and Hippo signaling pathways, etc. MiR-652, which was up-regulated in the fetal group, was transfected into C2C12 myoblasts to examine its role. miR-652 promoted(P≤0.05)proliferation and differentiation, but inhibited(P≤0.001) apoptosis at early period. Furthermore, miR-652 reduced(P≤0.001) the proportion of C2C12 myoblasts in the G1 phase while increasing(P≤0.01) the proportion of cells in the S and G2 phases. Dual-luciferase reporter assays indicated that ISL1 served as a target of miR-652. In general, these findings expand our understanding of yak skeletal muscle miRNAs, and suggested that miR-652 probably regulated myogenesis by regulating ISL1.
文摘目的 探讨乳腺癌患者血清核受体亚家族C组成员2(nuclear receptor subfamily 3, group C, member 2,NR3C2),DNA甲基化转移酶-3A[DNA(cytosine-5)-methyltransferase 3A,DNMT3A]水平及其临床诊断价值。方法收集复旦大学附属华东医院2017年5月~2020年12月期间住院的94例乳腺癌患者为乳腺癌组,另选取同期健康体检者86例作为对照组。酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测两组血清NR3C2和DNMT3A水平,Pearson法分析乳腺癌患者血清NR3C2和DNMT3A表达水平相关性,多因素Logistic回归分析乳腺癌发生的影响因素,受试者工作特征(receiver operating characteristic,ROC)曲线评估NR3C2和DNMT3A对乳腺癌的诊断价值。结果 乳腺癌组患者血清NR3C2水平为317.84±33.47 ng/L,低于对照组(374.25±47.72ng/L),DNMT3A的表达水平为451.63±75.47μg/L,高于对照组(349.85±63.72μg/L),差异有统计学意义(t=9.243,9.729,均P<0.05)。Pearson分析结果显示,乳腺癌患者血清NR3C2与DNMT3A表达水平存在明显负相关(r=-0.501,P=0.000)。Logistic回归分析结果显示,NR3C2高水平为乳腺癌发生的保护因素(OR=0.563,95%CI:0.372~0.851,P=0.006),DNMT3A高水平是乳腺癌发生的危险因素(OR=1.834,95%CI:1.249~2.693,P=0.002)。ROC曲线结果发现,血清NR3C2与DNMT3A诊断乳腺癌的曲线下面积(area under the curve,AUC)分别为0.853(0.791~0.915),0.930(0.896~0.965),当两者联合时其AUC为0.969(0.949~0.990),高于两者单独检测(Z=3.460,1.894,P=0.000,0.034)。结论 乳腺癌患者血清NR3C2表达水平降低,DNMT3A表达水平升高,两者联合检测能够提高乳腺癌的诊断价值。
基金National Natural Science Foundation of China,No.39770300,30070873the Overseas Chinese Affairs Office of the State Council Foundation,No.98-33
文摘AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells.
基金supported in part by NSF of China(11801539)the Fundamental Research Funds of the Central Universities(WK3470000019)the USTC Research Funds of the Double First-Class Initiative(YD3470002002)。
文摘Let Y be a closed 3-manifold such that all flat SU(2)-connections on Y are non-degenerate.In this article,we prove a Uhlenbeck-type compactness theorem on Y for stable flat SL(2,C)connections satisfying an L^(2)-bound for the real curvature.Combining the compactness theorem and a result from[7],we prove that the moduli space of the stable flat SL(2,C)connections is disconnected under certain technical assumptions.
文摘The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160～163), is re-described in the centric P21/c space group.
文摘目的探讨核受体亚家族2c成员2(nuclear receptor subfamily 2 group C member 2,NR2C2)在泌乳素瘤的表达水平及其与临床特征的关系。方法采用免疫组化染色和蛋白印迹实验检测46例泌乳素瘤患者的肿瘤组织NR2C2表达水平。用RNA干扰技术敲低MMQ细胞NR2C2表达水平,行细胞增殖实验检测细胞活力,流式细胞仪检测细胞凋亡率。结果按照Knosp分级将患者分为侵袭组和非侵袭组。侵袭组NR2C2表达的免疫组化评分为148.2±42.7,非侵袭组为45.2±28.72;NR2C2表达水平与肿瘤大小成正相关(r=0.327,P=0.039);疏松颗粒型患者的表达水平更高(P=0.003)。蛋白印迹实验检测NR2C2蛋白水平,筛选出Sh-B(23.4%)和Sh-C(34%)片段;干扰24h、48h和72h后,与对照组相比Sh-B组的细胞活力分别下降24.8%、39.2%和48.3%,Sh-C组分别下降19.1%、26.4%和32.5%(均P<0.05)。干扰24h后,Sh-B组AnnexinV阳性细胞为(10.3±3.1)%,PI阳性细胞为(7.3±2.1)%;Sh-C组分别为(8.5±2.3)%和(5.6±1.8)%;均明显高于对照组(均P<0.05)。结论 NR2C2能促进肿瘤生长,与催乳素腺瘤的发生发展密切相关。
基金Financial support for this study was provided by the Scicnce Foundation of Doctorate Program 8849104-11 from the National Committce of Education
文摘Chevkinite specimen from a rare-earth mineral deposit in Sichuan, southwest of China have been studied in detail by means of transmission electron microscope (TEM).The selected area electron diffraction (SAED)and convergent beam electron diffraction (CBED) patterns , obtained from different crystal zone axis direction , proved coincidently that the space group of chevkinite is C2/m . Fringe lattice image observation showed the mineral crystal is structurally uniform in microscale , and it is an ideal specimen for electron diffraction analysis . The mineral studied here is similar to the one from Bayan Obo , Inner Mongolia , China , in chemical composition and REE distribution . The chemical formula of the crystal is (Ce , La ,… , Ca) 4 Fe2+ (Fe, Ti, Nb) 2 O8 (Si2O7)2 From our study , we come to the conclusion that the space group of the natural chevkinite is C2/m , instead of P21/a as synthetic one . Up to now , chevkinite compositionally similar to the synthetic one , in which the complete replacements of Ce , La by Nd and Fe by Mg or Co occur , has not been discovered in nature . So we suggest that the name for synthesized chevkinite should be further discussed .
基金Project supported by the National Natural Science Foundation of China (Grant Nos. U1804130, U2004212, 11904084, and 11874141)the Henan Overseas Expertise Introduction Center for Discipline Innovation (Grant No. CXJD2019005)+1 种基金the China Postdoctoral Science Foundation (Grant No. 2021M690933)the Key Scientific Research Projects of Henan Education Department, China (Grant No. 22A140020)。
文摘MXenes are a new type of two-dimensional carbides with rich physical and chemical properties. The physics of MXenes, and thus the applications, are dominated by surface functional groups. Herein, the effects of different terminations(O,S, Se, Te) on the geometric and electronic properties of Nb_(2)C MXenes were studied via density functional theory(DFT)calculations. Three adsorption sites were examined to determine the most stable configurations. The results showed that both the types and the positions of surface functional groups influence the geometric stability and physical characters of Nb_(2)C. The S and Se terminations make the Nb_(2)C MXenes to be semiconductor, while Nb_(2)C MXenes with other terminations(O, Te) are conductor. The electron location function, density of states, Bader charge distribution, and the projected crystal orbital Hamilton population were conducted to explain the origin of adsorption stability and electronic nature difference. Our results provide a fundamental understanding about the effects of surface terminations on the intrinsic stability and electronic properties of Nb_(2)C MXenes.
