长薄鳅胚胎发育的观察

1999年5月,作者首次通过人工繁殖获得长薄鳅的受精卵,并对其胚胎发育特征进行了连续的观察。卵膜无粘性,吸水后卵周间隙明显膨胀扩大,卵膜径3.67-4.00 mm,平均3.79mm,属漂流性卵。胚胎发育可分为26个时期,初孵仔鱼长5.0mm左右,通体透明无色素。     

Preservation effects on stable isotope ratios and consequences for the reconstruction of energetic pathways

Stable isotope analysis provides a powerful tool for describing the energetic pathways in a variety of ecosystems. However, isotope ratios of animal tissues can be altered by preservation methods, potentially leading to biased estimates of energy pathways when they are not taken into account. Here, we investigated the direct preservation effects of formalin, ethanol, NaCl, and drying on the δ¹³C and δ¹⁵N of fish muscle tissues, as well as the ultimate effects on the reconstruction of the energy pathways. All preservation methods, except drying, had significant impacts on δ¹³C and δ¹⁵N values. The effects of preservation appear to be highly taxa-specific and no significant time-dependent variations in nearly 2-year duration of preservation. δ¹³C and δ¹⁵N values were generally changed dramatically within the early stage of the preservation process and became stable over a relatively long-term preservation. Using an isotopic balance mixing model, the isotope-based food web reconstruction reveals that, without preservation correction, the importance of the pelagic energetic pathways for the fishes could be misestimated, except for the drying preservation. These results highlight that preservation can bias the interpretation of food web reconstruction results.     

蚕沙有机肥的养分特性及其肥效

将废弃蚕沙进行无害化处理和适度发酵开发出蚕沙有机肥,分析了其养分特点,并采用盆栽试验研究了蚕沙有机肥的肥效.结果表明:发酵蚕沙有机肥的全氮、全磷、全钾含量与堆肥前相比显著提高,分别比堆肥前提高了58.0%、84.4%和29.7%;添加微生物菌剂可有效缩短发酵时间,并能减少堆肥过程的碳、氮损失.施用发酵后蚕沙的小白菜和番茄种子的发芽指数均大于80%,对作物发芽没有抑制作用.施用发酵蚕沙有机肥不仅可提高小白菜产量、营养养分、Vc含量,减少硝酸盐积累量,还可提高土壤pH值,增加土壤速效养分和有机质含量,增强土壤酶活性,其效果优于发酵羊粪有机肥处理.     

Transforming activity of a novel mutant of HPV16 E6E7 fusion gene

An optimized recombinant HPV16 E6E7 fusion gene(HPV16 ofE6E7)was constructed according to codon usage for mammalian cell expression,and a mutant of HPV16 ofE6E7 fusion gene(HPV16 omfE6E7)was generated by site-directed mutagenesis at L57G,C113R for the E6 protein and C24G,E26G for the E7 protein for HPV16 ofE6E7 [patent pending(CN 101100672)].The HPV16 omfE6E7 gene constructed in this work not only lost the transformation capability to NIH 3T3 cells and tumorigenicity in SCID mice,but also maintained very good stability and antigenicity.These results suggests that the HPV16 omfE6E7 gene should undergo further study for application as a safe antigen-specific therapeutic vaccine for HPV16-associated tumors.     

Drosophila klaroid encodes a SUN domain protein required for Klarsicht localization to the nuclear envelope and nuclear migration in the eye

KASH (Klarsicht/Anc-1/Syne homology) domain proteins are cytoskeleton-associated proteins localized uniquely to the outer nuclear membrane. Klarsicht is a KASH protein required for nuclear migration in differentiating cells of the Drosophila eye. The C-terminal KASH domain of Klarsicht resides in the perinuclear space, and the cytoplasmic moiety connects to the microtubule organizing center. In C. elegans and vertebrate cells, SUN (Sad1/UNC-84) domain proteins reside in the inner nuclear membrane and tether KASH proteins to the outer nuclear membrane. Is there a Drosophila SUN protein that performs a similar function, and if so, is it like Klarsicht, obviously essential for nuclear positioning only in the eye? Here, we identify Drosophila Klaroid, a SUN protein that tethers Klarsicht. klaroid loss-of-function mutants are indistinguishable phenotypically from klarsicht mutants. Remarkably, neither gene is essential for Drosophila viability or fertility, and even in klaroid klorsicht double mutants, the only obvious external morphological defect is rough eyes. In addition, we find that klaroid and klarsicht are required for nuclear migration in differentiating neurons and in non-neural cells. Finally, while perinuclear Klaroid is ubiquitous in the eye, Klarsicht expression is limited to differentiating cells and may be part of the trigger for apical nuclear migration.     

人羊膜上皮细胞移植及基因治疗帕金森病大鼠

观察人羊膜上皮细胞(human amniotic epithelial cell,HAEC及)人脑源性神经营养因子(brain-derived neurotrophic factor,BDNF基)因修饰的HAEC在帕金森病(Parkinson’sdisease,PD)模型大鼠脑内的长期存活和对旋转行为的治疗效果。用包装BDNFcDNA的慢病毒转染原代HAEC(HAEC/BDNF),HAEC/BDNF与HAEC分别植入6-羟基多巴胺损伤的PD模型大鼠纹状体内,观察动物的旋转行为,用免疫组织化学方法鉴定移植物在体内的存活。结果表明,治疗组PD大鼠的旋转行为改善明显达14周,HAEC/BDNF组能使恢复时间提前。免疫组织化学方法发现移植细胞在14周后仍有少量存活且部分表达BDNF、酪氨酸羟化酶,纹状体内星形胶质细胞增生。实验结果说明,HAEC和BDNF基因修饰的HAEC移植对PD模型大鼠的行为有一定改善,HAEC可以作为一种治疗PD的供体细胞。     

中国人群脂蛋白脂肪酶基因突变与高脂血症的相关性研究

为进行脂蛋白脂肪酶基因突变与中国人群高脂血症的相关性研究,采用单链构象多态性分析结合DNA序列测定的方法,对386例(其中108例高脂血症患者,278例正常对照)中国人群进行突变筛查。结果发现1个新的沉默突变L103L,1个错义突变P207L,3个剪接突变Int3/3′-ass/C(-6)→T和普遍存在的S447X多态性,其中发生在高脂血症组的P207L杂合子为亚洲首报,并对先证者的家系进行了研究,认为P207L是家族性高脂血症的病因之一,而在正常对照组中也有发现的Int3/3′-ass/C(-6)→T,对以往研究认为其是高脂血症易患因素的观点提出了相反的报告,对于普遍认为有益的多态性位点S447X,进一步研究认为其对于正常人群,特别是健康男性的保护作用更强。结论:脂蛋白脂肪酶基因变异与高脂血症的相关性十分复杂多样,大规模的人群筛查具有重要意义。     

Simultaneous determination of dronedarone and its active metabolite debutyldronedarone in human plasma by liquid chromatography-tandem mass spectrometry: application to a pharmacokinetic study

Dronedarone is a derivative of amiodarone--a popular antiarrhythmic drug. It was developed to overcome the limiting iodine-associated toxicities of amiodarone. Debutyldronedarone is a major circulating active metabolite of dronedarone in humans. To investigate the pharmacokinetics of dronedarone, a rapid, simple, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously determine dronedarone and debutyldronedarone in human plasma using amiodarone as internal standard (IS). Acetonitrile with IS was used to precipitate proteins from a 50-μL aliquot of plasma. Effective chromatographic separation was performed on a CAPCELL PAK C(18) MG (100 mm × 4.6 mm, 5 μm) column with gradient elution (5 mmol/L ammonium acetate-acetonitrile, with each phase containing 0.2% acetic acid) at a flow rate of 0.7 mL/min. Complete separation was achieved within 5.5 min. Detection was carried out on an tandem mass spectrometer in multiple reaction monitoring mode using a positive atmospheric pressure chemical ionization interface. A lower limit of quantification of 0.200 ng/mL was achieved for both dronedarone and debutyldronedarone, with acceptable precision and accuracy. The linear range of the method was from 0.200 to 200 ng/mL for each analyte. Intra- and inter-day precisions were lower than 7.2% in relation to relative standard deviation, while accuracy was within ±5.1% in terms of relative error for analytes. Our findings demonstrate the successful application of the validated LC-MS/MS method to a pharmacokinetic study after a single oral administration of 400mg dronedarone to six healthy volunteers.