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71.
Li-chun WANG Song-qing TANG Yan-mei LI Hong-lin ZHAO Cheng-hong DONG Ping-fang CUI Shao-hui MA Yun LIAO Long-ding LIU Qi-han LI 《Virologica Sinica》2010,(2)
The comparative analysis of the biological characterization and the genetic background study of EV71 circulating strains is commonly recognized as basic work necessary for development of an effective EV71 vaccine. In this study, we sequenced five EV71 circulating strains, isolated from Fuyang, Hefei, Kunming and Shenzhen city of China and named them FY-23, FY-22, H44, K9 and S1 respectively. The sequence alignment demonstrated their genotypes be C4. The genetic distance of the VP1 gene from these isolates s... 相似文献
72.
Eun Bae Kim Jee Soo Son Qian Kun Zhang Nam Kyung Lee Sung Hee Kim Jin Huk Choi Sang Kee Kang Yun Jaie Choi 《Current microbiology》2010,61(1):29-36
Genetic engineering of Lactococcus lactis to produce a heterologous protein may cause potential risks to the environment despite the industrial usefulness of engineered
strains. To reduce the risks, we generated three auxotrophic recombinant L. lactis subsp. lactis IL1403 strains expressing a heterologous protein, BmpB, using thyA- and alr-targeting integration vectors: ITD (thyA
−
alr
+
bmpB
+), IAD (thyA
+
alr
−
bmpB
+), and ITDAD (thyA
−
alr
−
bmpB
+). After construction of integration vectors, each vector was introduced into IL1403 genome. Integration of BmpB expression
cassette, deletion of thyA, and inactivation of alr were verified by using PCR reaction. All heterologous DNA fragments except bmpB were eliminated from those recombinants during double crossover events. By using five selective agar plates, we also showed
thymidine auxotrophy of ITD and ITDAD and d-alanine auxotrophy of IAD and ITDAD. In M17G and skim milk (SYG) media, the growth of the three recombinants was limited.
In MRS media, the growth of IAD and ITDAD was limited, but ITD showed a normal growth pattern as compared with the wild-type
strain (WT). All the recombinants showed maximal BmpB expression at an early stationary phase when they were cultivated in
M17G supplemented with thymidine and d-alanine. These results suggest that auxotrophic recombinant L. lactis expressing a heterologous protein could be generated to reduce the ecological risks of a recombinant L. lactis. 相似文献
73.
Yang YX Heo S Jin Z Yun JH Choi JY Yoon SY Park MS Yang BK Chae BJ 《Animal reproduction science》2009,112(3-4):199-214
Modern genotype primiparous and multiparous sows (Yorkshire x Landrace, n=48) were used to evaluate effects of dietary lysine intake during late gestation and lactation, and their interaction on reproductive performance. Sows were randomly allotted to two gestation lysine (G, 0.6% or 0.8% lysine) treatments based on parity in a 2 x 2 factorial arrangement, and each treatment had 12 replicates comprising 1 sow. Then all the sows were assigned to two lactation lysine (L, 1.0% or 1.3% lysine) treatments within parity and gestation treatments in a 2 x 2 x 2 factorial design, and each treatment comprised six replicates with 1 sow/replicate during lactation. Feeding higher lysine level during gestation increased sow body weight and backfat thickness (P=0.001) and body condition was better (P=0.001) in multiparous than that of primiparous sows. Both of the lysine levels during lactation and parity influenced sow body condition and reproductive performance (P<0.05). Higher lysine intake during lactation increased the concentrations of total solids (P=0.024), protein (P=0.001) and solids not-fat (P=0.042) in colostrum and total solids (P=0.001), protein (P=0.001), fat (P=0.001) and solids not-fat (P=0.005) in milk. Protein concentration of milk was greater (P=0.001) in multiparous sows than that of primiparous sows. Feeding of high lysine diets resulted in an increment of plasma urea N (P=0.010; P=0.047) and a decrease of creatinine (P=0.045; P=0.002) on the day of postfarrowing and weaning, respectively. Furthermore, as lysine intake increased, the secretions of insulin, FSH, and LH were increased (P<0.05) and multiparous sows showed higher (P<0.05) concentrations of FSH and LH pulses on the day of postfarrowing and weaning, respectively. These results indicated that higher lysine intake than that recommended by NRC [NRC, 1998. Nutrient Requirements of Swine, 10th ed. National Academy Press, 458 Washington, DC] could improve sow performance during late gestation and lactation. Furthermore primiparous sows need higher lysine intake than multiparous sows. Moreover, nutritional impacts on reproduction may be mediated in part through associated effects on circulating LH concentration. 相似文献
74.
目的:通过PET/CT检查观察脂肪肝患者肝脏及其他组织对18F脱氧葡萄糖(18F-FDG)摄入变化,探讨脂肪肝与糖脂代谢的相关性。方法:36例做PET/CT的健康和2型糖尿病男性患者,分为对照组(n=18例);脂肪肝组(n=9例);糖尿病脂肪肝组(n=9例)。常规测血糖、血脂及肝肾功能。PET/CT测肝脏CT值和肝脏、肾皮质,骨骼肌组织18F-FDG的最大标准摄入值(SUVmax)及平均标准摄入值(SUVmean)。结果:1.糖尿病脂肪肝组的TG显著高于单纯脂肪肝组和正常对照组,P=0.0003,0.0000。单纯脂肪肝组的TG亦显著高于正常对照组,P=0.028。2.糖尿病脂肪肝组的肝脏18F-FDG的SUVmean和SUVmax显著高于正常对照组的SUVmean和SUVmax,P=0.0054,0.0133。单纯脂肪肝组的肝脏SUVmean和SUVmax亦高于正常对照组,但比较无统计学差异。脑皮质、肾皮质和骨骼肌组织的18F-FDG的SUVmean和SUVmax三组间比较无显著性差异。3.Spearman相关性分析发现FBG与TG显著正相关(r=0.59919,P=0.0004);FBG和TG与肝脏的CT值显著负相关(r=-0.55625,P=0.0004;r=-0.45739,P=0.0097)。结论:脂肪肝与空腹血糖和甘油三酯升高显著相关。脂肪肝及2型糖尿病脂肪肝患者肝脏对葡萄糖摄取增高。 相似文献
75.
Lee IK Jung JY Seok SJ Kim WG Yun BS 《Bioorganic & medicinal chemistry letters》2006,16(21):5621-5624
New free radical scavengers, inoscavin D (1) and methylinoscavin D (2), were isolated from the methanolic extract of the fruiting bodies of Inonotus xeranticus (Hymenochaetaceae), along with the known compounds phelligridin D (3), 3,4-dihydroxybenzaldehyde (4), and 3,4-dihydroxybenzoic acid (5). Their structures were established by various spectroscopic analyses. Compounds 1 and 3 were proposed to be biosynthesized from the oxidative coupling of the precursor hispidin with 3,4-dihydroxybenzaldehyde and 3,4-dihydroxybenzoic acid, respectively. These compounds exhibited significant scavenging activity against the ABTS radical cation, and compounds 2 and 4 displayed moderate superoxide radical scavenging activity. 相似文献
76.
Cuiping Xie Feiming Ye Ning Zhang Yuxue Huang Yun Pan Xiaojie Xie 《Journal of cellular and molecular medicine》2021,25(15):7280-7293
Chemokine C-C motif ligand 7 (CCL7), a member of CC chemokine subfamily, plays pivotal roles in numerous inflammatory diseases. Hyper-activation of inflammation is an important characteristic of abdominal aortic aneurysm (AAA). Therefore, in the present study, we aimed to determine the effect of CCL7 on AAA formation. CCL7 abundance in aortic tissue and macrophage infiltration were both increased in angiotensin II (Ang II)-induced AAA mice. Ex vivo, CCL7 promoted macrophage polarization towards M1 phenotype. This effect was reversed by the blockage of CCR1, a receptor of CCL7. CCL7 up-regulated JAK2/STAT1 protein level in macrophage, and CCL7-induced M1 activation was suppressed by JAK2/STAT1 pathway inhibition. To verify the effect of CCL7 on AAA in vivo, either CCL7-neutralizing antibody (CCL7-nAb) or vehicles were intraperitoneally injected 24 hours prior to Ang II infusion and subsequently every three days for 4 weeks. CCL7-nAb administration significantly attenuated Ang II-induced luminal and external dilation as well as pathological remodelling. Immunostaining showed that CCL7-nAb administration significantly decreased aneurysmal macrophage infiltration. In conclusion, CCL7 contributed to Ang II-induced AAA by promoting M1 phenotype of macrophage through CCR1/JAK2/STAT1 signalling pathway. 相似文献
77.
Yun Gao Yi Pan Tingting Wang Ying Yao Wenbo Yuan Xue Zhu Ke Wang 《Acta biochimica et biophysica Sinica》2021,(12):1650-1661
Papillary thyroid cancer (PTC) usually has favorable prognosis;however,distant metastasis is a leading cause of death associated with PTC.MicroRNA-99a-3p (miR-9... 相似文献
78.
βγ-晶状体蛋白是主要分布于脊椎动物眼睛晶状体内的水溶性结构蛋白。非晶状体βγ-晶状体蛋白从微生物到高等哺乳动物都有过报道。微生物中发现的非晶状体βγ-晶状体蛋白主要作为环境胁迫应急蛋白,在恶劣环境中发挥对细菌的自我保护作用,如ProteinS。在哺乳动物中,非晶状体βγ-晶状体蛋白被推测能够参与胚胎的皮肤发育与分化调节,具有肿瘤抑制等重要的生理功能,如黑色素瘤缺失蛋白。但是,对于它们的生化特性、生理功能和作用机制知之甚少。本文从蛋白结构、基因起源和生物学功能等方面简要介绍目前非晶状体βγ-晶状体蛋白的相关研究进展。 相似文献
79.
A peptide-based 2-D liquid phase fractionation (PF2D) system was used in a quantitative proteomic analysis of hepatocellular carcinoma. 2-D liquid maps of peptide specimens showed better resolution than those of proteins, leading to the identification of differentially expressed proteins. Peptide-based PF2D gave well-matched theoretical and experimental pI values and was proven to be a very efficient and versatile analytical tool for both large-scale profiling and quantification of phosphoproteins in disease biomarker discovery. 相似文献
80.
Choi HS Wang Z Richmond W He X Yang K Jiang T Sim T Karanewsky D Gu XJ Zhou V Liu Y Ohmori O Caldwell J Gray N He Y 《Bioorganic & medicinal chemistry letters》2006,16(8):2173-2176
A series of 2-amino-9-aryl-7H-pyrrolo[2,3-d]pyrimidines were designed and synthesized to target focal adhesion kinase (FAK). A number of these pyrrolopyrimides exhibited low micromolar inhibitory activities against focal adhesion kinase, and their preliminary SAR was established via systematic chemical modifications. The 2-amino-9-aryl-7H-pyrrolo[2,3-d]pyrimidines represent a new class of kinase inhibitors. 相似文献