In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the...In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the PDF and HTML(full text).展开更多
从本实验室构建的家蚕蛹cDNA文库中筛选到一条新的cDNA序列,生物信息学分析发现其编码的蛋白质序列与果蝇Enhancer of split基因[E(spl)]编码的DNA结合转录调控因子bHLH(helix-loop-helix)有较高的同源性,将该基因命名为BmE(spl)-like(B...从本实验室构建的家蚕蛹cDNA文库中筛选到一条新的cDNA序列,生物信息学分析发现其编码的蛋白质序列与果蝇Enhancer of split基因[E(spl)]编码的DNA结合转录调控因子bHLH(helix-loop-helix)有较高的同源性,将该基因命名为BmE(spl)-like(Bombyx mori Enhancer of split like)。该基因的ORF长606 bp,编码201个氨基酸残基,预测蛋白质分子质量22.3 kD,等电点9.7。构建重组表达质粒pET-28a-BmE(spl)-like并在E.coli BL21(DE3)菌株中表达BmE(spl)-like蛋白,经亲和层析和FPLC反向柱纯化融合蛋白His-BmE(spl)-like并制备了抗体效价1∶25 600以上的多克隆抗体。用qRT-PCR方法检测BmE(spl)-like在家蚕成虫发育期的转录水平最高,结合果蝇同源基因的功能,推测该基因与蚕蛾的翅发育相关;该基因在家蚕5龄幼虫各组织中的转录水平以表皮最高,马氏管中最低。Western blotting检测BmE(spl)-like在家蚕5龄幼虫性腺中的表达水平最高,其次是丝腺、表皮、脂肪体、肠组织,在头部、马氏管和气管中的表达水平极低,与qRT-PCR检测的BmE(spl)-like在各组织中的转录水平有些差异。展开更多
β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in vitro.However,because of the short survival time of the differentiated cells,clinical applications f...β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in vitro.However,because of the short survival time of the differentiated cells,clinical applications for this technique are limited.As such,we examined apoptosis of neurons differentiated from adipose-derived stromal cells induced with β-mercaptoethanol in vitro using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and transmission electron microscopy.The results revealed that the number of surviving cells decreased and apoptosis rate increased as induction time extended.Taken together,these results suggest that apoptosis occurring in the process of adipose-derived stromal cells differentiating into neurons is the main cause of cell death.However,the mechanism underlying cellular apoptosis should be researched further to develop methods of controlling apoptosis for clinical applications.展开更多
The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu（NH3）4]2^＋ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical co...The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu（NH3）4]2^＋ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical copper powder with a uniform size of 3.5 ± 0.5 μtm was processed to obtain flake copper powder having a uniform size of 8-10 μm, excellent dispersibility and uniform shape. The spherical copper powder of 2.5 ±0.3 μm in size, flake copper, glass frit and vehicle were mixed to prepare copper paste, which was fired in 910-920℃ to obtain BME-MLCC （base metal multilayer ceramic capacitor） with a dense surface of end termination, high adhesion and qualified electrical behavior. Polarized light photo and SEM were employed to observe the copper end termination of BME-MLCC. The rough interface from the interracial reaction between glass and chip gives high adhesion.展开更多
Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively ...Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.展开更多
In order to further understand the effects of drought stress on hydraulic characteristics and the relationship between hydraulic conductivity and aquaporins or water channels of root systems of three wolfberry cultiva...In order to further understand the effects of drought stress on hydraulic characteristics and the relationship between hydraulic conductivity and aquaporins or water channels of root systems of three wolfberry cultivars(Lycium chinense Mill.),hydraulic conductivity of 2-yearold pot-grown seedlings was measured under drought stress,rewatering,and treatment with exogenous mercuric chloride andβ-mercaptoethanol.Under moderate and severe drought stress levels,the most significant decrease of hydraulic conductivity was 37.3%and 24.0%,respectively,in the‘Ningqi 5’cultivar compared with the nonstressed control.After rewatering,the rate of recovery in specific conductivity was most rapid in the‘Mengqi 1’cultivar,at 0.058 and 0.072 kg MPa^-1 m^-2 s^-1 h^-1 under moderate and severe drought stress levels,respectively.The‘Mengqi 1’cultivar had the highest recovery degree of hydraulic conductivity under two concentrations ofβ-ME(500 or 1000 lmol L^-1),reaching 82.4%and 88.5%,respectively,of the initial conductivity.The adaptive capacity of hydraulic conductivity in the‘Ningqi 5’cultivar was weaker than in the‘Ningqi 1’and‘Mengqi 1’cultivars under drought stress.The recovery capacity of hydraulic conductivity in‘Mengqi 1’cultivar was stronger than the‘Ningqi 1’and‘Ningqi 5’cultivars after rewatering.Aquaporins of the‘Ningqi 1’cultivar root systems had the highest binding affinity with mercuric chloride,which was the most likely cause in the decrease in hydraulic conductivity,whereas aquaporins of‘Mengqi 1’root systems had the weakest binding affinity.The inhibitory effect of mercuric chloride was readily eliminated byβ-mercaptoethanol in the‘Mengqi 1’cultivar.The hydraulic characteristics of this cultivar were more sensitive to drought,mercuric chloride andβ-mercaptoethanol than the other cultivars.展开更多
This study was conducted to investigate the effects of different concentrations ofβ-mercaptoethanol on the development ability of oocytes in Dorper sheep at the age of 6 weeks.In this study,6 Dorper sheep of 6 weeks ...This study was conducted to investigate the effects of different concentrations ofβ-mercaptoethanol on the development ability of oocytes in Dorper sheep at the age of 6 weeks.In this study,6 Dorper sheep of 6 weeks old were chosen to induce oocyte collection in vivo by gonadotropin,and A and B grade cumulus oocyte complexes were obtained(COCs)with different concentrations of(0,50,70 and 100μmol/L)ofβ-mercaptoethanol in the mature liquid.The cleavage rate and blastocyst rate were counted after matured oocytes and capacitated sperm were co-incubated and fertilized eggs were cultivated.The results showed that compared with the cleavage rate(59.13%)and the blastocyst rate(12.17%)of the control group,the cleavage rates(60.87%,63.48%and 65.22%)and blastocyst rates(14.78%,17.39%and 21.74%)of the test groups I,II and III were higher(P>0.05),and the order was test group III>test group II>test group I>control group.The cleavage rate and blastocyst rate of the 100μmol/Lβ-mercaptoethanol group increased by 6.09 percentage points and 9.57 percentage points,respectively.It indicated that the addition of a certain amount ofβ-mercaptoethanol in the mature liquid could improve the developmental ability of oocytes and the quality of fertilized eggs of the 6-week-old Doper sheep.When theβ-mercaptoethanol concentration was within 100μmol/L,the cleavage rate and the blastocyst rate of oocytes were on the rise.The optimal concentration ofβ-mercaptoethanol in the mature liquid still needs further study.展开更多
文摘In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the PDF and HTML(full text).
文摘从本实验室构建的家蚕蛹cDNA文库中筛选到一条新的cDNA序列,生物信息学分析发现其编码的蛋白质序列与果蝇Enhancer of split基因[E(spl)]编码的DNA结合转录调控因子bHLH(helix-loop-helix)有较高的同源性,将该基因命名为BmE(spl)-like(Bombyx mori Enhancer of split like)。该基因的ORF长606 bp,编码201个氨基酸残基,预测蛋白质分子质量22.3 kD,等电点9.7。构建重组表达质粒pET-28a-BmE(spl)-like并在E.coli BL21(DE3)菌株中表达BmE(spl)-like蛋白,经亲和层析和FPLC反向柱纯化融合蛋白His-BmE(spl)-like并制备了抗体效价1∶25 600以上的多克隆抗体。用qRT-PCR方法检测BmE(spl)-like在家蚕成虫发育期的转录水平最高,结合果蝇同源基因的功能,推测该基因与蚕蛾的翅发育相关;该基因在家蚕5龄幼虫各组织中的转录水平以表皮最高,马氏管中最低。Western blotting检测BmE(spl)-like在家蚕5龄幼虫性腺中的表达水平最高,其次是丝腺、表皮、脂肪体、肠组织,在头部、马氏管和气管中的表达水平极低,与qRT-PCR检测的BmE(spl)-like在各组织中的转录水平有些差异。
文摘β-mercaptoethanol can induce adipose-derived stromal cells to rapidly and efficiently differentiate into neurons in vitro.However,because of the short survival time of the differentiated cells,clinical applications for this technique are limited.As such,we examined apoptosis of neurons differentiated from adipose-derived stromal cells induced with β-mercaptoethanol in vitro using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and transmission electron microscopy.The results revealed that the number of surviving cells decreased and apoptosis rate increased as induction time extended.Taken together,these results suggest that apoptosis occurring in the process of adipose-derived stromal cells differentiating into neurons is the main cause of cell death.However,the mechanism underlying cellular apoptosis should be researched further to develop methods of controlling apoptosis for clinical applications.
文摘The preparation of fine copper powders by chemical reduction method was investigated. The reaction of [Cu（NH3）4]2^＋ complex with hydrazine hydrate gives spherical monodispersed fine copper powders. The spherical copper powder with a uniform size of 3.5 ± 0.5 μtm was processed to obtain flake copper powder having a uniform size of 8-10 μm, excellent dispersibility and uniform shape. The spherical copper powder of 2.5 ±0.3 μm in size, flake copper, glass frit and vehicle were mixed to prepare copper paste, which was fired in 910-920℃ to obtain BME-MLCC （base metal multilayer ceramic capacitor） with a dense surface of end termination, high adhesion and qualified electrical behavior. Polarized light photo and SEM were employed to observe the copper end termination of BME-MLCC. The rough interface from the interracial reaction between glass and chip gives high adhesion.
基金Supported by the National Natural Science Foundation of China(No.20775061)
文摘Specific oligonucleotides such as telomere DNA and aptamer often undergo conformational changes upon ligand binding. Composite reagent composed of o-phthalaldehyde and β-mercaptoethanol（OPAME） has been extensively applied to fluorescent detection of amino compounds based on the reaction of primary amino-group, herein we proposed a general spectrofluorometry for ions and small molecules due to conformational changes upon ligand binding taking K^＋ and ATP as examples. In a borate controlled buffer medium, telomere DNA could react with OPAME, giving a thio-subtituted isoindole compound with strong fluorescence emission at 455 nm when excited at 340 nm. It was found that however, the fluorescence emission was greatly reduced in the presence of K^＋ since the formation of the quadruplex structure inhibits the reaction activity of amino-groups of telomere DNA. In order to testify the general application of OPAME reagent based on the conformational change of oligonucleotides, we further proposed a sensitive method of ATP based on its highly selective interaction with ATP-aptamer. The above mentioned applications show that the spectrofluorometry with the aid of OPAME reagent is simple, label free that is expected to be potentially general for DNA conformational change-based target detection.
基金the National Natural Science Foundation of China(Grant No.31560380)Chief Expert of Modern Agricultural Traditional Chinese Medicine Industry System in Gansu Province(GARS-ZYC-1)the Open Project of Qinghai Key Laboratory of Qinghai-Tibet Plateau Biological Resources(Grant No.2017-ZJ-Y10)。
文摘In order to further understand the effects of drought stress on hydraulic characteristics and the relationship between hydraulic conductivity and aquaporins or water channels of root systems of three wolfberry cultivars(Lycium chinense Mill.),hydraulic conductivity of 2-yearold pot-grown seedlings was measured under drought stress,rewatering,and treatment with exogenous mercuric chloride andβ-mercaptoethanol.Under moderate and severe drought stress levels,the most significant decrease of hydraulic conductivity was 37.3%and 24.0%,respectively,in the‘Ningqi 5’cultivar compared with the nonstressed control.After rewatering,the rate of recovery in specific conductivity was most rapid in the‘Mengqi 1’cultivar,at 0.058 and 0.072 kg MPa^-1 m^-2 s^-1 h^-1 under moderate and severe drought stress levels,respectively.The‘Mengqi 1’cultivar had the highest recovery degree of hydraulic conductivity under two concentrations ofβ-ME(500 or 1000 lmol L^-1),reaching 82.4%and 88.5%,respectively,of the initial conductivity.The adaptive capacity of hydraulic conductivity in the‘Ningqi 5’cultivar was weaker than in the‘Ningqi 1’and‘Mengqi 1’cultivars under drought stress.The recovery capacity of hydraulic conductivity in‘Mengqi 1’cultivar was stronger than the‘Ningqi 1’and‘Ningqi 5’cultivars after rewatering.Aquaporins of the‘Ningqi 1’cultivar root systems had the highest binding affinity with mercuric chloride,which was the most likely cause in the decrease in hydraulic conductivity,whereas aquaporins of‘Mengqi 1’root systems had the weakest binding affinity.The inhibitory effect of mercuric chloride was readily eliminated byβ-mercaptoethanol in the‘Mengqi 1’cultivar.The hydraulic characteristics of this cultivar were more sensitive to drought,mercuric chloride andβ-mercaptoethanol than the other cultivars.
基金Supported by Earmarked Fund for Construction of National Wool Sheep Industry Technology Research System(CARS-39-24)Fund for Science and Technology Innovation Team in Shanxi Province(201705D131028-20)
文摘This study was conducted to investigate the effects of different concentrations ofβ-mercaptoethanol on the development ability of oocytes in Dorper sheep at the age of 6 weeks.In this study,6 Dorper sheep of 6 weeks old were chosen to induce oocyte collection in vivo by gonadotropin,and A and B grade cumulus oocyte complexes were obtained(COCs)with different concentrations of(0,50,70 and 100μmol/L)ofβ-mercaptoethanol in the mature liquid.The cleavage rate and blastocyst rate were counted after matured oocytes and capacitated sperm were co-incubated and fertilized eggs were cultivated.The results showed that compared with the cleavage rate(59.13%)and the blastocyst rate(12.17%)of the control group,the cleavage rates(60.87%,63.48%and 65.22%)and blastocyst rates(14.78%,17.39%and 21.74%)of the test groups I,II and III were higher(P>0.05),and the order was test group III>test group II>test group I>control group.The cleavage rate and blastocyst rate of the 100μmol/Lβ-mercaptoethanol group increased by 6.09 percentage points and 9.57 percentage points,respectively.It indicated that the addition of a certain amount ofβ-mercaptoethanol in the mature liquid could improve the developmental ability of oocytes and the quality of fertilized eggs of the 6-week-old Doper sheep.When theβ-mercaptoethanol concentration was within 100μmol/L,the cleavage rate and the blastocyst rate of oocytes were on the rise.The optimal concentration ofβ-mercaptoethanol in the mature liquid still needs further study.
