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951.
Gun Hyuk Jang In-Sook Park Sun Hee Lee You Mie Lee 《Biochemical and biophysical research communications》2009,382(3):486-14755
Malachite green (MG) is a triphenyl methane dye used in various fields that demonstrates high toxicity to bacteria and mammalian cells. When bud stage zebrafish embryos were treated with MG at 125, 150, and 175 ppb for 14 h, the development of trunk including intersomitic vessels was inhibited in MG-treated flk-1-GFP transgenic embyos. MG clearly induced whole growth retardation. MG induced severe cell death in trunk intersomite region of zebrafish embryos and in human vascular endothelial cells in a dose-dependent manner. MG inhibited heart rates and cardiac looping. MG attenuated whole blood formation and inhibited vascular endothelial growth factor (VEGF)-induced receptor (R)-2 phosphorylation in vascular endothelial cells. In conclusion, MG significantly alters the cardiovascular development causing growth retardation in zebrafish through the blocking VEGFR-2 activation in early cardiovascular development. It suggests that MG may be an environmental toxic agent with the potential to induce embryonic cardiovascular defects in vertebrates. 相似文献
952.
Han Lu Shengwu You Fujun Zhang Buwei Yu 《Biochemical and biophysical research communications》2009,390(3):872-662
Post-translational modification of proteins by the small ubiquitin-like modifiers (SUMOs) has emerged as an important regulatory mechanism for alteration of protein activity, stability, and cellular localization. It has been reported that SUMOylation plays an important role in some activities of neuronal cells. However, the link between SUMOylation and activity-dependent stimuli of neurons remains to be elucidated. Here we showed that KCl-induced depolarization increased SUMO conjugation in SHSY5Y cell line in a time-dependent manner. The increase of SUMOylation was largely dependent on calcium influx and intracellular calcium signals. Our study demonstrates the link between the activity-dependent stimuli and global SUMOs conjugation, which may play an important role in activity-dependent signals of neurons. 相似文献
953.
Xiaoyan You Yiping Liu Xiaosong Jiang Huarui Du Zuohua Liu Qing Zhu 《Biochemical genetics》2009,47(7-8):511-520
Using PCR-SSCP with five primer pairs, we detected six single nucleotide polymorphisms of the H-FABP gene: 332G → A, 534G → A, 783C → T, 835C → T, 1198T → C, and 2329C → T. Chi-square results showed significant differences (P < 0.05) in genotype frequency among breeds in Fragment 1 and extremely significant differences (P < 0.01) in Fragments 2–4. We found a significant association between Fragment 2 genotype and muscle fiber number, Arg and Thr (P < 0.05); between Fragment 3 genotype and living weight, carcass weight, breast muscle weight, abdominal fat weight, and abdominal fat percentage (P < 0.05); between Fragment 4 genotype and Thr, Phe, and inosinic acid (P < 0.05). It was concluded that H-FABP was the major gene influencing slaughter performance and meat quality or was linked with the major gene in these strains and that the C783T mutation could be used as a candidate molecular genetic marker for breeding selection. The combination M1C2–B2B2–D1D1 is an ideal model for breeding in these strains because it can improve slaughter and meat quality traits. 相似文献
954.
Dongdong Xu Feng You Zhihao Wu Jun Li Jing Ni Zhizhong Xiao Peijun Zhang Yongli Xu 《Genetica》2009,137(2):151-158
Interspecific reciprocal crosses between the two flatfishes Paralichthys olivaceus and P. dentatus yielded hybrids with different viabilities. Specifically, the hybrids of P. olivaceus female and P. dentatus male (HI) were found to be viable, while the reciprocal hybrids from P. dentatus female and P. olivaceus male (HII) were completely inviable. All the HII individuals showed morphological deformities and died before first feeding.
The chromosome analysis showed that HI individuals had the same chromosome number as parents. However, two chromosomes were
missing in HII offspring indicating that the latter were aneuploids. Genomic inheritance from the parents to F1 progeny was also examined by amplified fragment length polymorphism (AFLP) analyses, and the results showed differences between
reciprocal hybrids. Almost all AFLP bands (97.71%) observed in parents were passed on to HI individuals. In contrast, only
86.64% of the AFLP bands from parents were scored in HII individuals. Frequency of lost parental bands was thus significantly
higher in HII than that in HI and intraspecific crosses, which was probably associated with chromosomal elimination. In addition,
higher segregation distortions were found in hybrids than in controls, although these differences were not significant. The
present study indicates that chromosomal elimination and loss of AFLP loci occurred in inviable HII individuals, while such
genomic changes were not found in viable HI individuals. Possible implications of such difference on genomic changes for asymmetric
viability in reciprocal hybrids are discussed. 相似文献
955.
956.
Yu Ding ;Yongyan Li ;Junyan You ;Li Yang ;Bobei Chen ;Jianxin Lu ;Min-Xin Guan 《遗传学报》2009,36(4):241-250
Mutations in mitochondrial 12S rRNA gene are one of the most important causes of aminoglycoside-induced and nonsyndromic hearing loss. Here we report the characterization of one Han Chinese pedigree with aminoglycoside-induced and nonsyndromic hearing loss. This Chinese family carrying the 12S rRNA A1555G mutation exhibited high penetrance and expressivity of heating impairment. In particular, penetrances of hearing loss in this family pedigree were 43.8% and 25%, respectively, when aminoglycoside-induced heating loss was included or excluded. Mutational analysis of entire mitochondrial genomes in this family showed the homoplasmic A1555G mutation and a set of variants belonging to haplogroup Y2. Of these, the A14693G variant occurred at the extremely conserved nucleotide (conventional position 54) of the TψC-loop of tRNA^Clu and was absent in 156 Chinese controls. Nucleotides at position 54 of tRNAs are often modified, thereby contributing to the structural formation and stabilization of functional tRNAs. Thus, the structural alteration of tRNA by the A14693G variant may lead to a failure in tRNA metabolism and impair mitochondrial protein synthesis, thereby worsening mitochondrial dysfunctions altered by the A1555G mutation. Therefore, the tRNA^Glu A14693G variant may have a potential modifier role in increasing the penetrance and expressivity of the deafness-associated A1555G mutation in this Chinese pedigree. 相似文献
957.
Mutations in mitochondrial 12S rRNA gene are one of the most important causes of aminoglycoside-induced and nonsyndromic hearing loss. Here we report the characterization of one Han Chinese pedigree with aminoglycoside-induced and nonsyndromic hearing loss.This Chinese family carrying the 12S rRNA A1555G mutation exhibited high penetrance and expressivity of hearing impairment. In particular, penetrances of hearing loss in this family pedigree were 43.8% and 25%, respectively, when aminoglycoside-induced heating loss was included or excluded. Mutational analysis of entire mitochondrial genomes in this family showed the homoplasmic A1555G mutation and a set of variants belonging to haplogroup Y2. Of these, the A14693G variant occurred at the extremely conserved nucleotide (conventional position 54) of the TψC-loop of tRNAGlu and was absent in 156 Chinese controls. Nucleotides at position 54 of tRNAs are often modified, thereby contributing to the structural formation and stabilization of functional tRNAs. Thus, the structural alteration of tRNA by the A14693G variant may lead to a failure in tRNA metabolism and impair mitochondrial protein synthesis, thereby worsening mitochondrial dysfunctions altered by the A1555G mutation. Therefore, the tRNAalu A14693G variant may have a potential modifier role in increasing the penetrance and expressivity of the deafness-associated AI555G mutation in this Chinese pedigree. 相似文献
958.
Dian-Bing Wang Ruifu Yang Zhi-Ping Zhang Li-Jun Bi Xiang-Yu You Hong-Ping Wei Ya-Feng Zhou Ziniu Yu Xian-En Zhang 《PloS one》2009,4(11)
Bacillus anthracis, the causative agent of anthrax disease, could be used as a biothreat reagent. It is vital to develop a rapid, convenient method to detect B. anthracis. In the current study, three high affinity and specificity monoclonal antibodies (mAbs, designated 8G3, 10C6 and 12F6) have been obtained using fully washed B. anthracis spores as an immunogen. These mAbs, confirmed to direct against EA1 protein, can recognize the surface of B. anthracis spores and intact vegetative cells with high affinity and species-specificity. EA1 has been well known as a major S-layer component of B. anthracis vegetative cells, and it also persistently exists in the spore preparations and bind tightly to the spore surfaces even after rigorous washing. Therefore, these mAbs can be used to build a new and rapid immunoassay for detection of both life forms of B. anthracis, either vegetative cells or spores. 相似文献
959.
异黄酮衍生物的设计、合成与抗肿瘤活性 总被引:2,自引:0,他引:2
为了提高大豆苷元的生物利用度以改善其抗肿瘤活性,利用前药原理对大豆苷元进行修饰。本文根据前药原理成功设计合成了5个新型大豆苷元磺酸酯衍生物(3~7),所有化合物的结构均经IR、MS、元素分析和。HNMR确证。体外细胞初步活性筛选试验结果表明,部分标题化合物也具有一定的抗肿瘤活性。 相似文献
960.
茶皂素光波干法提取与产品开发 总被引:1,自引:0,他引:1
本文考察茶皂素的微波光波组合无溶剂提取方法,发现微波光波提取干法不用溶剂,仅用微量的DMF作为能量传递介质,提取速度是传统提取方法的1800倍以上,成本明显降低.利用高倍FM、IR等手段对微波提取机理进行初步研究,从微波对植物组织结构的影响上阐明次生代谢产物的微波提取机理.利用提取的茶皂素开发成洗发香波,对多个配方进行了多方面的性能评价,其中两个配方的多项指标达到或优于国家标准. 相似文献