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11.
AIM: To investigate the relationships between Iα1 hs1,2 VNTR polymorphism and IgA nephropathy. METHODS: Four hundred and ninteen patients with IgA nephropathy and their first-degree relatives were recruited. Two hundred and one sex and age-matched normal Chinese Han volunteers were also recruited as controls. After extracting genomic DNA, the VNTR genotypes of Iα1 hs1,2 region were determined by PCR and electrophoresis, and the results were analyzed by transmission disequilibrium test (TDT) and haplotype relative risk (HRR) in the families, and Chi-Square test in the case-control analysis. RESULTS: ① TDT analyses showed that B allele of the Iα1 hs1,2 VNTR region was significantly more transmitted from heterozygous parents to patients than expected (101 Trios, χ2=6.818, P<0.01), extended TDT produced the same results (164 families, χ2=7.583, P<0.01). ② Consistent with the TDT results, HRR also showed that B allele was over-transmitted to patients (P<0.05, χ2=4.122, HRR=1.180), and the BB genotype conferred a higher risk of developing the disease (P<0.05, χ2=4.411, OR=1.538). ③ The case-control study indicated that the B allele had a higher frequency in the IgA nephropathy group (χ2=6.968, P<0.05). CONCLUSION: B allele in Iα1 hs1,2 VNTR region is associated with susceptibility to IgA nephropathy.  相似文献   
12.
AIM:To construct the SNP haplotypes and the haplotype blocks of FcαR1 gene in Chinese Han population in Guangdong province.METHODS:Genomic DNA was extracted from 100 healthy Chinese Han subjects.Genotypes of the SNPs in FcαR1 gene were determined by PCR and direct sequencing.Constructing the SNP haplotypes and the haplotype blocks of FcαR1 gene by 12 SNPs that is its minor allele frequency were more than 0.1 with Haploview soft.RESULTS:There are 3 haplotype blocks in FcαR1 gene in Chinese Han population in Guangdong province.The number of haplotypes in each haplotype blocks was from 3 to 7 (average 5.33).However,the number of common haplotypes in each blocks was from 2 to 3 (average 2.3).CONCLUSION:Our results show the existence of the block-like structures and the common haplotypes in each block in FcαR1 gene.It provides a useful tool for the genome research and the mapping of disease contributing genes/variants in this gene.  相似文献   
13.
AIM: To study the effect of human FAT10 on the apopotosis of HEK293 cells using flag-tagged human FAT10 protein.METHODS: The fragment of FAT10 gene was cloned into the pcDNA3-flag vector,which was identified by PCR,enzyme digestion and sequencing.The reconstructed plasmids were transfected into HEK293 cells.The expression of introduced FAT10 in the normal cultured and starved cells was detected respectively by Western blotting.XTT assay and DNA ladder method were used to analyze the effect of FAT10 on the apoptosis of starved HEK293 cells.RESULTS: The reconstructed plasmids were highly expressed in HEK293 cells with different expression mode at the mormal cultured and starved state.The livability of starved FAT10 overexpressed HEK293 cells was significantly lower than that of normal cultured cells.DNA ladder was observed in the starved FAT10 overexpressed cells,but not in the normal cultured cells.CONCLUSION: The eukaryotic expressed plasmids of flag-tagged FAT10 were constructed successfully,and highly expressed in HEK293.Overexpressed FAT10 enhances the apoptosis in the starved HEK293 cells.  相似文献   
14.
妊娠的建立和维持归因于胚体的信号和黄体对孕酮的产生,在反刍动物,胚体滋养层分泌的激素抑制子宫内膜产生前列腺素PGF2α。在发情周期的绵羊,孕酮下调子宫内膜腔上皮和子宫腺上皮孕酮受体基因的表达,并伴随着上皮雌激素受体和催产素受体的增加。在催产素的作用下,子宫开始分泌溶黄体作用的前列腺素F2α。在妊娠绵羊,孕体滋养层产生的干扰素可作用于子宫内膜而直接抑制雌激素受体基因和催产素受体基因的转录。孕酮、干扰素、胎盘催乳素和生殖激素共同组成了一个"作用网络"来调节子宫的功能分化和子宫腺的形态发生,从而维持绵羊妊娠。本文综述了绵羊妊娠识别、建立和维持的信号系统。  相似文献   
15.
AIM: To illustrate the effects of overexpression of stathmin 1 on melanocyte growth and the relationship between C terminal motif and stathmin 1 function.METHODS: The overexpression vector and C terminal mutant coding vector were constructed. The vectors were transfected into melanocytes by Lipofectamine 2000. MTT and FCM were used to inspect the cell growth, Western blotting was a tool in caspase-3 measurement, and spectrophotography was used to detect the melanin products and tyrosinase activity.RESULTS: The vectors of overexpression and mutation were constructed and transfected into melanocytes successfully. Both of them inhibited the melanocyte growth, induced apoptosis, and decreased the melanin products and tyrosinase activity.CONCLUSION: Overexpression of stathmin 1 inhibits melanocyte growth, melanin products and tyrosinase activity. The change of C terminal motif could not affect the role of stathmin 1 in melanocyte markedly.  相似文献   
16.
荔枝的功能及活性成分研究现状   总被引:1,自引:0,他引:1  
自古以来,中国就有荔枝各组织保健医疗功能的记载。现代医学、营养学、植物化学和药理学为荔枝的医疗和保健功能提供了坚实的证据,其功能活性成分正不断被揭示。对荔枝果肉抗氧化、"上火"和致敏原,果皮抗氧化和抗癌功效,核抗癌、抗病毒、降血糖、调血脂等功能和相关成分研究现状进行了介绍。  相似文献   
17.
A fast and efficient method for the isolation of the C-glucosidated xanthones mangiferin and isomangiferin from the South-African plant Cyclopia genistoides was developed for the first time. The procedure involved extraction, liquid–liquid partitioning with ethyl acetate and subsequent precipitation of mangiferin and isomangiferin from methanol and acetonitrile–water fractions, respectively. Additionally, two benzophenone derivatives: 3-C-β-glucosides of maclurin and iriflophenone, were isolated from C. genistoides extracts using semi-preparative HPLC. Apart from the above, the isolation procedure also yielded hesperidin and small amounts of luteolin. The structures of the compounds were determined by 1D and 2D NMR experiments and/or LC-DAD-ESI–MS. The selected Cyclopia constituents were screened for pro-apoptotic activity on TNF-α-stimulated synovial cells isolated from rheumatoid arthritis patients. The strongest effect, measured as percent of apoptotic cells, was recorded for isomangiferin (75%), followed by iriflophenone 3-C-β-glucoside (71%), hesperidin (67%) and mangiferin (65%). The results are encouraging for further studies on the use of the above compounds in the treatment of rheumatoid arthritis.  相似文献   
18.
Soil urease is crucial for the nitrogen cycle and its association with humic acids (HAs) is a fundamental requirement for its stability. In this work, the chemical characteristic of two HA fractions (HA1, ≥50 kDa; HA2, 10–50 kDa) extracted from lignite was evaluated, and their effects on the activity and stability of Jack Bean urease were also studied. HA1 and HA2 exhibited different structural properties in the micro-FT-IR and 13C NMR spectra and influences on urease stability during 12 days of incubation: HA1 stabilized the urease activity. After 12 days, the residual activity of urease, at pH 6.0, 7.0 and 8.0, was 2.1, 2.6 and 3.9 times higher in the treatment of HA1-urease than in the free urease, respectively. With pH values increasing, the stability of free urease decreased and that of HA1-urease increased, which indicated that HA1 improved the stability of urease in the solution, especially at the alkaline condition.  相似文献   
19.
Edible coatings based on high molecular weight chitosan, pure or combined with methylcellulose or oleic acid, were applied to fresh-cut carrots cv. Nantesa by simple immersion and by applying a vacuum pulse (5 kPa for 4 min). Water vapour resistance, colour, mechanical properties and respiration rates of non-coated and coated samples were determined. Coatings improved sample appearance, since they diminished the occurrence of the white blush during storage. When applied by simple immersion, they neither conferred significant barrier properties nor the preservation of the mechanical properties of fresh-cut carrot samples. In contrast, coating application with a vacuum pulse enhanced all the positive effects, since the resistance of water vapour transmission of the samples was significantly improved, and better preservation of the sample colour and mechanical response during cold storage was obtained. Differences in film composition did not significantly affect the coating behaviour, probably due to the variability induced by different factors when coatings were applied to the carrot surface.  相似文献   
20.
Desotamides A, a cyclohexapeptide produced by the deep-sea-derived Streptomyces scopuliridis SCSIO ZJ46, displays notable antibacterial activities against strains of Streptococcus pnuemoniae, Staphylococcus aureus, and methicillin-resistant Staphylococcus epidermidis (MRSE). In this study, to further explore its antibacterial potential and reveal the antibacterial structure-activity relationship of desotamides, 13 cyclopeptides including 10 new synthetic desotamide A analogues and wollamides B/B1/B2 were synthesized and evaluated for their antibacterial activities against a panel of Gram-positive and -negative pathogens. The bioactivity data reveal that residues at position II and VI greatly impact antibacterial activity. The most potent antibacterial analogues are desotamide A4 (13) and A6 (15) where l-allo-Ile at position II was substituted with l-Ile and Gly at position VI was simultaneously replaced by d-Lys or d-Arg; desotamides A4 (13) and A6 (15) showed a 2–4-fold increase of antibacterial activities against a series of Gram-positive pathogens including the prevalent clinical drug-resistant pathogen methicillin-resistant Staphylococcus aureus (MRSA) with MIC values of 8–32 μg/mL compared to the original desotamide A. The enhanced antibacterial activity, broad antibacterial spectrum of desotamides A4 and A6 highlighted their potential as new antibiotic leads for further development.  相似文献   
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