目的研究黏多糖贮积症ⅣA型（mucopolysaccharidosis type ⅣA，MPSⅣA）患者发病的分子遗传学机制，揭示其基因型与表现型的相互关系，为产前基因诊断等创造必要的前提条件。方法采用尿糖胺聚糖（glycosaminoglycans，GAGs）定性检测...目的研究黏多糖贮积症ⅣA型（mucopolysaccharidosis type ⅣA，MPSⅣA）患者发病的分子遗传学机制，揭示其基因型与表现型的相互关系，为产前基因诊断等创造必要的前提条件。方法采用尿糖胺聚糖（glycosaminoglycans，GAGs）定性检测法对疑似MPSIVA型的先证者进行初诊，然后采用PCR及扩增产物直接测序法对先证者及其家庭成员进行突变检测。在检出GALNS基因c．1567T〉G新突变后，先后建立XspI酶切鉴定法和扩增阻碍突变系统（amplification refractory mutation system，ARMS）快速特异鉴定法，对随机采集的110名正常对照与先证者及其家庭成员的GALNS基因第14外显子进行序列分析，同时采用生物信息学方法对蛋白质二级、三级结构进行预测，以及直接测定患儿GALNS酶活性的方法，对该新突变进行致病性鉴定。结果先证者尿检呈弱阳性GAGs（±），其GALNS基因第14外显子内存在杂合的c．1567T〉G终止密码突变，第4外显子存在杂合的c．374C〉T错义突变，为两种突变的复合杂合子。其妹突变类型与先证者完全相同，其母仅在第14外显子存在杂合的终止密码突变，为该病的携带者，其父仅在第4外显子存在杂合的错义突变，也为杂合子；第14外显子的PCR产物经XspI酶切后，正常对照组切出28bp、120bp、399bp3条带，而患者和携带者的母亲均切出28bp、120bp、148bp和399bp4条带；用ARMS特异引物扩增后，正常对照组均扩增阴性，而患者及携带者均扩增阳性；蛋白质二级、三级结构预测结果显示：c ．1567T〉G变异导致终止密码（TAG）突变为谷氨酸（GAG），使多肽链延长了92个氨基酸残基，导致蛋白质二、三级结构发生明显改变，而正常对照无此变化。酶活性测定的结果显示：患者的GALNS酶活性仅为8．3nmol／17h／mgpr，明显低于正常值（正常参考值为41．9～92．1nmol／17h，／mgpr）。结论c．1567T〉G变异是一种新的致病性突变，是引起该家系患儿发病的根本原因。展开更多
A high power GaSb-based laser diode with lasing wavelength at 2 μm was fabricated and optimized. With the optimized epitaxial laser structure, the internal loss and the threshold current density decreased and the int...A high power GaSb-based laser diode with lasing wavelength at 2 μm was fabricated and optimized. With the optimized epitaxial laser structure, the internal loss and the threshold current density decreased and the internal quantum efficiency increased. For uncoated broad-area lasers, the threshold current density was as low as 144 A/cm2 （72 A/cm^2 per quantum well）, and the slope efficiency was 0.2 W/A. The internal loss was 11 cm^-1 and the internal quantum efficiency was 27.1%. The maximum output power of 357 mW under continuous-wave operation at room temperature was achieved. The electrical and optical properties of the laser diode were improved.展开更多
目的快速、准确地对MorquioA综合征[又称黏多糖贮积症ⅣA型（mucopolysaccharidosis type ⅣA，MPSⅣA）]高危胎儿做出产前基因诊断，从而及时而高效地防止患儿的出生，以最大程度减少流产对母体的伤害。同时，为今后的植入前遗传学诊断...目的快速、准确地对MorquioA综合征[又称黏多糖贮积症ⅣA型（mucopolysaccharidosis type ⅣA，MPSⅣA）]高危胎儿做出产前基因诊断，从而及时而高效地防止患儿的出生，以最大程度减少流产对母体的伤害。同时，为今后的植入前遗传学诊断（preimplantation genetic diagnosis，PGD）创造必要的前提条件。方法在明确先证者病因及其父母基因型的基础上，应用已建立的突变特异性扩增系统（amplification refractor ymutation system，ARMS）直接鉴定法、变性高效液相色谱（denaturing high performance liquid chromatography，DHPLC）快速筛检法，结合DNA序列分析法，对1例已孕10周的MPSIVA高危胎儿的GALNS基因相应突变位点进行快速检测和鉴定。结果胎儿的DHPLC筛检结果显示第1外显子和第10外显子的PCR产物都有异常双峰，而相应正常对照均只有正常单峰；用GALNS基因ARMS特异引物扩增的结果显示：胎儿有相应的特异扩增产物，而正常对照无；普通引物扩增产物的测序结果显示：胎儿GALNS基因的第1外显子和第10外显子分别获得了父源性的c．106—111del（p．L36-L37del）杂合缺失突变和母源性的c．1097T〉C（P．L366P）杂合错义突变，为两种突变的复合杂合子。结论该高危胎儿是一带有与先证者完全相同基因型的MorquioA综合征病胎，应尽早终止妊娠；ARMS法、DHPLC法结合DNA序列分析法是快速、准确产前基因诊断MPSⅣA高危胎儿的有效方法，特别适用于已明确病因的高危胎儿的早期诊断；其中，ARMS法和DHPLC法还特别适用于大批量正常对照组的快速鉴别，对于新突变的致病性鉴定起着重要的作用。展开更多
5-Hydroxymethylfurfural （5-HMF）, a water-soluble compound extracted from wine-processed Fructus corni, is a novel hepatic protectant for treating acute liver injury. The present study was designed to investigate the...5-Hydroxymethylfurfural （5-HMF）, a water-soluble compound extracted from wine-processed Fructus corni, is a novel hepatic protectant for treating acute liver injury. The present study was designed to investigate the protective effect of 5-HMF in human L02 hepatocytes injured by D-galactosamine （GAIN） and tumor necrosis factor-α （TNF-α） in vitro and to explore the underlying mechanisms of action. Our results showed that 5-HMF caused significant increase in the viability of L02 cells injured by GalN/TNF-α, in accordance with a dose-dependent decrease in apoptotic cell death confirmed by morphological and flow cytometric analyses. Based on immunofluorescence and Western blot assays, we found that GalN/TNF-α induced ER stress in the cells, as indicated by the disturbance of intracellular Ca^2＋ concentration, the activation of protein kinase RNA （PKR）-like ER kinase （PERK）, phosphorylation of eukaryotic initiation factor 2 alpha （eIF2α）, and expression of ATF4 and CHOP proteins, which was reversed by 5-HMF pre-treatment in a dose-dependent manner. The anti-apoptotic effect of 5-HMF was further evidenced by balancing the expression of Bcl-2 family members. In addition, the knockdown of PERK suppressed the expression of phospho-PERK, phospho-eIF2α, ATF4, and CHOP, resulting in a significant decrease in cell apoptosis after the treatment with GalN/TNF-α. 5-HMF could enhance the effects of PERK knockdown, protecting the cells against the GalN/TNF-α insult. In conclusion, these findings demonstrate that 5-HMF can effectively protect GalN/TNF-α-injured L02 hepatocytes against ER stress-induced apoptosis through the regulation of the PERK- eIF2α signaling pathway, suggesting that it is a possible candidate for liver disease therapy.展开更多
基金supported by the Beijing Natural Science Foundation, China (Grant No. 4112058)
文摘A high power GaSb-based laser diode with lasing wavelength at 2 μm was fabricated and optimized. With the optimized epitaxial laser structure, the internal loss and the threshold current density decreased and the internal quantum efficiency increased. For uncoated broad-area lasers, the threshold current density was as low as 144 A/cm2 （72 A/cm^2 per quantum well）, and the slope efficiency was 0.2 W/A. The internal loss was 11 cm^-1 and the internal quantum efficiency was 27.1%. The maximum output power of 357 mW under continuous-wave operation at room temperature was achieved. The electrical and optical properties of the laser diode were improved.
基金supported by grants from Natural Science Foundation of Jiangsu Higher Education Institutions of China(No.13KJB360010)Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine(TCM) Prevention and Treatment of Tumor(No.012092002002)+1 种基金China and Europe Taking Care of Healthcare Solutions,CHETCH(No.PIRSES-GA-2013-612589)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘5-Hydroxymethylfurfural （5-HMF）, a water-soluble compound extracted from wine-processed Fructus corni, is a novel hepatic protectant for treating acute liver injury. The present study was designed to investigate the protective effect of 5-HMF in human L02 hepatocytes injured by D-galactosamine （GAIN） and tumor necrosis factor-α （TNF-α） in vitro and to explore the underlying mechanisms of action. Our results showed that 5-HMF caused significant increase in the viability of L02 cells injured by GalN/TNF-α, in accordance with a dose-dependent decrease in apoptotic cell death confirmed by morphological and flow cytometric analyses. Based on immunofluorescence and Western blot assays, we found that GalN/TNF-α induced ER stress in the cells, as indicated by the disturbance of intracellular Ca^2＋ concentration, the activation of protein kinase RNA （PKR）-like ER kinase （PERK）, phosphorylation of eukaryotic initiation factor 2 alpha （eIF2α）, and expression of ATF4 and CHOP proteins, which was reversed by 5-HMF pre-treatment in a dose-dependent manner. The anti-apoptotic effect of 5-HMF was further evidenced by balancing the expression of Bcl-2 family members. In addition, the knockdown of PERK suppressed the expression of phospho-PERK, phospho-eIF2α, ATF4, and CHOP, resulting in a significant decrease in cell apoptosis after the treatment with GalN/TNF-α. 5-HMF could enhance the effects of PERK knockdown, protecting the cells against the GalN/TNF-α insult. In conclusion, these findings demonstrate that 5-HMF can effectively protect GalN/TNF-α-injured L02 hepatocytes against ER stress-induced apoptosis through the regulation of the PERK- eIF2α signaling pathway, suggesting that it is a possible candidate for liver disease therapy.
