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991.
Chang Hyun Oh Jin Woo Kim Joon Hee Hong 《Nucleosides, nucleotides & nucleic acids》2013,32(8):871-878
Novel vinyl branched apiosyl nucleosides were synthesized in this study. Apiosyl sugar moiety was constructed by sequential ozonolysis and reductions. The bases (uracil and thymine) were efficiently coupled by glycosyl condensation procedure (persilyated base and TMSOTf). The antiviral activities of the synthesized compounds were evaluated against the HIV-1, HSV-1, HSV-2, and HCMV. Compound 10β displayed moderate anti-HIV activity (EC50 = 17.3 μg/mL) without exhibiting any cytotoxicity up to 100 μM. 相似文献
992.
I. Basnak Ming Sun T. A. Hamor N. Spencer R. T. Walke 《Nucleosides, nucleotides & nucleic acids》2013,32(7-8):1275-1285
Abstract 5-Cyclohexyl-2′-deoxyuridine (I) is an example of a 5-substituted pyrimidine 2′-deoxynucleoside which exhibits no antiviral activity and which is not a substrate for either cellular or viral (herpes) kinases. Despite the fact that a cursory inspection of NMR spectra of the compound, taken in DMSO-d 6 solution, suggested that the compound had a normal conformation, we here show that in the crystal and in aqueous solution (analysed by 2D NMR techniques), the conformation of this nucleoside has a syn-glycosidic and C4′-exo (4E) sugar pucker conformation. 相似文献
993.
Tam Dinh Le Vo Ji-seun Ko Seung Hwan Lee Si Jae Park Soon Ho Hong 《Biotechnology and Bioprocess Engineering》2013,18(6):1062-1066
This study investigated the effect of glutamate decarboxylase from Neurospora crassa OR74A on GABA production in Escherichia coli. GABA is one of the inhibitory neurotransmitters in the mammalian central nervous system, and can be used as a precursor of promising biopolymer Nylon 4. E. coli that overexpressed N. crassa glutamate decarboxylase was cultured at various pH levels and temperatures to determine optimum conditions for GABA production. When the recombinant E. coli strain was cultured at 30°C and pH 3, a final GABA concentration of 5.26 g/L was obtained from 10 g/L of monosodium glutamate (MSG), corresponding to a GABA yield of 86.23%. 相似文献
994.
Recovery of native protein from potato root water by expanded bed adsorption with amberlite XAD7HP 总被引:3,自引:0,他引:3
Fan-Kui Zeng Hong Liu Peng-Jun Ma Gang Liu 《Biotechnology and Bioprocess Engineering》2013,18(5):981-988
Potato root water (PRW) contains ~1.5% protein. In this study, expanded bed adsorption (EBA) chromatography with Amberlite XAD7HP resin adsorbent was used to isolate native protein from crude PRW. The optimal pH and ionic strength for potato protein binding onto Amberlite XAD7HP were 5.0 and 20 mmol/L. The EBA-refined proteins were dried by vacuum freeze drying and spray drying at varying outlet temperatures. Results indicated that low temperature spray drying was the most cost effective method with respect to retaining protease inhibitor activities. The dried protein concentrates appeared bright yellow or dark reddish brown, with a total glycoalkaloid content of ~170 μg/g. The protease inhibitor activity was ~400 mg/g and 11 ~ 12 mg/g for trypsin inhibition and chymotrypsin inhibition, respectively. The results presented here suggest that EBA using Amberlite XAD7HP as the adsorbent is a feasible strategy for the direct adsorption of native protein from crude PRW. 相似文献
995.
Hao Zhang Jing Sun Xianting Liu Chuan Hong Yuanbo Zhu Aiping Liu Siqi Li Huiyuan Guo Fazheng Ren 《Journal of microbiology (Seoul, Korea)》2013,51(6):777-782
Lactobacillus paracasei subsp. paracasei LC01 (LC01) can tolerate intestinal stresses and has antioxidant activity. To evaluate the effect of the bacterium on human intestinal microflora, a randomized, double-blind, placebo-controlled human trial was carried out. Fifty-two healthy adult volunteers were randomized equally to two groups. One group consumed 12% (wt/vol) skimmed milk supplemented with 1010 CFU of LC01 each day for the 4-week treatment period, and then consumed placebo in the next treatment period, separated by a 2-week washout. The other group followed the reverse order. Group-specific real-time PCR and biochemical analyses was used to determine the intestinal bacterial composition of fecal samples collected at the end of every period, and the concentration of short-chain fatty acids and ammonia. A significant inhibition in fecal Escherichia coli and increase in Lactobacillus, Bifidobacterium, and Roseburia intestinalis were observed after consumption of LC01. Acetic acid and butyric acid were significantly higher in the probiotic stage and fecal ammonia was significantly lower. The results indicated a modulation effect of LC01 on the intestinal microflora of young adults, suggesting a beneficial effect on bowel health. LC01 may have potential value as a probiotic. 相似文献
996.
Hong Li Gui-Rong Sun Ya-Dong Tian Rui-Li Han Guo-Xi Li Xiang-Tao Kang 《Journal of applied genetics》2013,54(2):209-213
In the present study, a total of 860 chickens from a Gushi–Anka F2 resource population were used to evaluate the genetic effect of the gga-miR-1614-3p gene. A novel, silent, single nucleotide polymorphism (SNP, +5 C>T) was detected in the gga-miR-1614-3p gene seed region through AvaII polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) and PCR products sequencing methods. Associations between the SNP and chicken growth, meat quality and carcass traits were performed by association analysis. The results showed that the SNP was significantly associated with breast muscle shear force and leg muscle water loss rate, wing weight, liver weight and heart weight (p?<?0.05), and highly significantly associated with the weight of the abdominal fat (p?<?0.01). The secondary structure of gga-miR-1614 and the free energy were altered due to the variation predicted by the M-fold program. 相似文献
997.
This study aimed to elucidate the mechanisms that may lead to an efficient strategy to induce a suitable host response of the vaginal mucosa upon exposure to intravaginally delivered exogenous compounds. It was hypothesized that the upregulation of intercellular adhesion molecule (ICAM)-1 gene expression may reflect the inflammatory response evoked by exogenous compounds. Major emphasis was placed on ethylenediamine tetraacetic acid (EDTA) which was added as a synergistic agent to conventional spermicidal agents or anti-HIV drugs. The levels of ICAM-1 mRNA were examined as a surrogate marker for inflammatory response in human vaginal epithelial cells upon exposure to EDTA or interleukin (IL)-1β (i.e. positive control, 25 mM). The effects of estrogen on EDTA-induced ICAM-1 expression were also evaluated for the estrogen involvement in the inflammatory process of the vaginal mucosa. ICAM-1 expression in human vaginal cells (VK2/E6E7 cells) increased as EDTA concentration added to human vaginal cell lines increased. The effects of estrogen on EDTA-induced ICAM-1 expression in human vaginal epithelial cells were estrogen-concentration dependent; estrogen at lower concentrations (~1–10 nM) did not affect ICAM-1 expression, whereas estrogen at higher concentrations (~100 nM–1 µM) attenuated ICAM-1 expression. The influence of estrogen in ICAM-1 expression suggests the beneficial effects of estrogen on the regulation of vaginal homeostasis. Identification and quantification of specific surrogate markers for the inflammatory response evoked by exogenous compounds and their regulation by estrogen will lead to an efficient strategy against sexually transmitted diseases including AIDS. 相似文献
998.
999.
Jae Hyeong Kim Eun-Kyung Yoon Hye-Jin Chung Seong-Yeol Park Kyeong-Man Hong Chang-Hun Lee Yeon-Su Lee Kyungho Choi Young Yang Kyungtae Kim In-Hoo Kim 《Apoptosis : an international journal on programmed cell death》2013,18(1):110-120
Microtubule inhibitors (MTIs) such as Taxol have been used for treating various malignant tumors. Although MTIs have been known to induce cell death through mitotic arrest, other mechanisms can operate in MTI-induced cell death. Especially, the role of p53 in this process has been controversial for a long time. Here we investigated the function of p53 in Taxol-induced apoptosis using p53 wild type and p53 null cancer cell lines. p53 was upregulated upon Taxol treatment in p53 wild type cells and deletion of p53 diminished Taxol-induced apoptosis. p53 target proteins including MDM2, p21, BAX, and β-isoform of PUMA were also upregulated by Taxol in p53 wild type cells. Conversely, when the wild type p53 was re-introduced into two different p53 null cancer cell lines, Taxol-induced apoptosis was enhanced. Among post-translational modifications that affect p53 stability and function, p53 acetylation, rather than phosphorylation, increased significantly in Taxol-treated cells. When acetylation was enhanced by anti-Sirt1 siRNA or an HDAC inhibitor, Taxol-induced apoptosis was enhanced, which was not observed in p53 null cells. When an acetylation-defective mutant of p53 was re-introduced to p53 null cells, apoptosis was partially reduced compared to the re-introduction of the wild type p53. Thus, p53 plays a pro-apoptotic role in Taxol-induced apoptosis and acetylation of p53 contributes to this pro-apoptotic function in response to Taxol in several human cancer cell lines, suggesting that enhancing acetylation of p53 could have potential implication for increasing the sensitivity of cancer cells to Taxol. 相似文献
1000.