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201.
目的探讨原发性肝癌患者肠道菌群变化及其与内毒素、炎性因子水平的相关性。方法选取2018年2月至2019年10月我院收治的80例原发性肝癌患者为观察组,另选同时期80例健康体检者为对照组。观察两组对象肠道菌群情况,同时检测两组对象血清内毒素和白细胞介素6(IL-6)、白细胞介素1(IL-1)及肿瘤坏死因子α(TNF-α)水平。采用Pearson检验进行相关性分析。结果观察组患者肠道双歧杆菌、乳杆菌和拟杆菌数量低于对照组;而肠杆菌和酵母菌数量高于对照组(均P0.05)。观察组患者血清内毒素、IL-6、IL-1、TNF-α水平均高于对照组(均P0.05)。Pearson相关性分析显示,肠道双歧杆菌、乳杆菌和拟杆菌数量与血清内毒素和IL-6、IL-1、TNF-α水平呈负相关,肠道肠杆菌和酵母菌数量与内毒素和IL-6、IL-1、TNF-α水平呈正相关(均P0.05)。结论原发性肝癌患者肠道菌群紊乱与内毒素和炎症因子水平具有相关性,肠道菌群失衡可能是促进该病病情发展的原因之一。 相似文献
202.
生物膜干涉(biolayer interferometry,BLI)技术可对抗体与抗原的相互作用进行亲和力、动力学的全面分析。在抗体克隆筛选、动力学常数测定中对链霉亲和素(streptavidin,SA)生物传感器的需求量较大,但目前鲜有关于SA传感器重复利用的报道。基于BLI技术、再生SA生物传感器建立一种使用再生后的传感器检测PDL1抗体与PDL1抗原亲和力的方法。通过将生物素化的PDL1抗原偶联至SA生物传感器上,再与单链抗体、双价单链抗体、完整抗体和双特异性抗体这4类PDL1抗体结合,计算抗原抗体的亲和力常数,利用甘氨酸(10 mmol·L-1,pH 1.7)再生SA传感器,再次进行分子间相互作用力分析。结果显示,重复性相对标准偏差(relative standard deviation,RSD)均值为6.87%,批间重复性RSD为0.82%,稳定性RSD均值为6.13%,说明运用甘氨酸再生后的SA生物传感器测分子间的亲和力数据可靠、重现性好、稳定性高,再生后的传感器可继续用于本样品的实时、无标记的抗原抗体相互作用力分析。BLI技术可节省检测成本,为SA传感器的重复利用提供理论依据。 相似文献
203.
Li Tang Xiaoyan Feng Feng He Rui Huang Jing He Bingshui Xiu Kun Chen Xiqin Yang Shigan Ling Heqiu Zhang 《Molecular biotechnology》2013,54(1):58-67
In order to overcome the instability of CpG ODN in vivo, sequence diversity, and individual differences, eleven CpG ODN fragments were meticulously selected and linked to form a Multi-CpG, which were repeatedly inserted into the cloning vector pUC19 for constructing the recombinant plasmid pUCpGs10 containing ten of Multi-CpG. Using the multi-genotype HCV E1 and multi-epitope complex HCV-T as immunogens, and plasmid pUCpGs10 as the immune adjuvant, Balb/c mice were immunized through nasal and subcutaneous immunization. Strong-specific humoral and cellular immune response were induced, which can obviously inhibit the growth of homograft expressing HCV antigen. The immune adjuvant effect of pUCpGs10 closely matched that of Freund’s complete adjuvant. The plasmid pUCpGs10 can significantly improve IgA content in serum and different mucosal extract and systematical T-cell response via intranasal immunization. In conclusions, the newly constructed immunostimulatory plasmid pUCpGs10 is able to effectively activate the humoral and cellular immune activity, and possesses activation on mucosal immune response. 相似文献
204.
Mei Ling Xu Hyoung Jin Kim Don Yong Chang Hong-Jin Kim 《Journal of microbiology (Seoul, Korea)》2013,51(3):389-393
Acidic protein levels in the milk decrease markedly as lactation progresses, suggesting that it is an important part of the colostrum. However, little attention has been paid to their biological function. In this study, we isolated the acidic protein fraction of bovine colostrum (AFC, isoelectric point <5) by anion-exchange chromatography, and investigated the effect of its dietary intake on influenza A (H1N1) virus infection. 100% of mice infected with 1 LD50 of the virus survived when administered AFC for 14 days prior to infection, compared with 33% survival when administered phosphate buffered saline (PBS). Moreover, consumption of AFC reduced the weight loss associated with infection. We propose that dietary intake of AFC has a prophylactic effect on influenza A virus infection. 相似文献
205.
Xiaolei Zhu Lan Ye Huiming Ge Ling Chen Nan Jiang Lai Qian Lingling Li Rong Liu Shen Ji Su Zhang Jiali Jin Dening Guan Wei Fang Renxiang Tan Yun Xu 《Aging cell》2013,12(1):85-92
Increasing evidence demonstrates that amyloid beta (Aβ) elicits mitochondrial dysfunction and oxidative stress, which contributes to the pathogenesis of Alzheimer's disease (AD). Identification of the molecules targeting Aβ is thus of particular significance in the treatment of AD. Hopeahainol A (HopA), a polyphenol with a novel skeleton obtained from Hopea hainanensis, is potentially acetylcholinesterase‐inhibitory and anti‐oxidative in H2O2‐treated PC12 cells. In this study, we reported that HopA might bind to Aβ1–42 directly and inhibit the Aβ1–42 aggregation using a combination of molecular dynamics simulation, binding assay, transmission electron microscopic analysis and staining technique. We also demonstrated that HopA decreased the interaction between Aβ1–42 and Aβ‐binding alcohol dehydrogenase, which in turn reduced mitochondrial dysfunction and oxidative stress in vivo and in vitro. In addition, HopA was able to rescue the long‐term potentiation induction by protecting synaptic function and attenuate memory deficits in APP/PS1 mice. Our data suggest that HopA might be a promising drug for therapeutic intervention in AD. 相似文献
206.
207.
Xiang-Jun?Jiang Yi?Hu Ling?Jiang Bin?Zou Ping?Song He?HuangEmail author 《Biotechnology and Bioprocess Engineering》2013,18(2):350-357
Statistical experimental designs combined with solvent engineering for optimization of enzymatic synthesis of L-ascorbyl palmitate were developed. First, the composition of the solvent for co-dissolving polar and apolar substrates was determined. The co-solvent mixture of tert-pentanol: DMSO at a ratio of 9:1 (v/v) and the optimal biocatalyst were obtained. Then, the Plackett-Burman design was implemented to screen the variables that significantly influence the conversion. The method of steepest ascent was used to approach the proximity of optimum. After determining the Plackett-Burman and steepest ascent designs, the optimum values were determined by central composite design under response surface methodology. The statistical analysis showed that the optimum reaction conditions (temperature 50°C, enzyme concentration 5.8 g/L, and substrate molar ratio 11:1, stirring rate 160 rpm, amount of molecular sieve 50 g/L, time 18 h) led to the maximum conversion (66.44%) and production concentration (20.63 g/L). A very satisfactory conversion (64.74%) and production concentration (20.13 g/L) could be achieved in short time (6 h). 相似文献
208.
Approximately 70 species of Bactrocera fruit flies (Diptera: Tephritidae) are polyphagous economic pests that attack many important agricultural crops. Several of these Bactrocera species are also highly invasive, and many countries operate continuous, large-scale trapping programs to detect incipient infestations. Detection programs rely heavily on traps baited with male lures, with males of some species responding to raspberry ketone (RK; or its synthetic analogue cue-lure [CL]) and males of other species responding to methyl eugenol (ME). These lures (plus naled, an insecticide) are currently applied as liquids, although this procedure is time-consuming and may expose workers to health risks. Recent field tests, conducted largely in Hawaii, have shown that traps baited with a solid formulation (termed a wafer) that contains both RK and ME (plus dichlorvos, an insecticide) capture as many or more B. dorsalis (Hendel) and B. cucurbitae (Coquillett) males as traps baited with the standard liquid lures. While these results are promising, a more complete evaluation of the solid formulation requires testing in a region with a diverse assemblage of Bactrocera species, since interspecific variation in male response to lures has been reported. The objective of the present investigation was to assess the relative effectiveness of liquid versus solid formulations of male lures in Malaysia, a country known to harbor a large assemblage of Bactrocera species. Based on a 12-week sampling period, we found that, contrary to the Hawaiian results, traps baited with the wafer captured significantly fewer males than traps baited with liquid lures for all five ME-responding taxa analyzed and for one of the three RK/CL-responding species analyzed. Possible explanations for the discrepancy between these and earlier findings are offered. 相似文献
209.
Aihong Li Cunhong Pan Linbo Wu Zhengyuan Dai Shimin Zuo Nin Xiao Ling Yu Yuhong Li Xiaoxiang Zhang Wenxia Xue Hongxi Zhang Xuebiao Pan 《Molecular breeding : new strategies in plant improvement》2013,32(1):1-13
Rice black streaked-dwarf virus (RBSDV) disease is recently expanding in southern China and poses a serious threat to rice crops. Few studies related to the genetics and breeding of RBSDV resistance have been reported. We have previously mapped a number of quantitative trait loci (QTLs) for RBSDV resistance by using a recombinant inbred line population of ‘Zhenshan 97’ (ZS97, susceptible)/‘Minghui 63’ (MH63, resistant) with natural infection data in two locations. In the present study, we confirmed the presence of a number of resistant QTLs on chromosomes 6, 7, and 9 from MH63 by using the same population in four different locations. We then focused on a major QTL, qRBSDV-6 MH , on chromosome 6 and introduced it into a highly susceptible japonica rice variety, ‘Huaidao 5’, using MH63 as the donor via marker-assisted selection, to generate seven backcross inbred lines (BILs). Natural infection and artificial inoculation-based tests revealed that all of the BILs had a significantly higher resistance to RBSDV than the recurrent parent. These results demonstrate that qRBSDV-6 MH is a stable major resistance QTL of high breeding value. We also constructed a set of chromosome segment substitution lines (CSSLs) specific to the qRBSDV-6 MH region and these used as fine mapping population. Combining the genotypes of CSSLs with the phenotypes from natural infection data in a highly RBSDV epidemic area during two different sowing seasons, we were able to precisely map qRBSDV-6 MH to the markers S18 and S23 at a physical distance of 627.6 kb on the Nipponbare reference genome. 相似文献
210.
Miaofei Xu Yufeng Qin Jianhua Qu Chuncheng Lu Ying Wang Wei Wu Ling Song Shoulin Wang Feng Chen Hongbing Shen Jiahao Sha Zhibin Hu Yankai Xia Xinru Wang 《PloS one》2013,8(11)