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11.
对栅藻B38的营养成分进行了全面分析,结果表明,栅藻藻粉中油脂含量14%,总糖含量13.86%,粗纤维3.52%,灰分4.28%,蛋白质49.0%,为高蛋白质类微藻。栅藻B38中含有23种脂肪酸。栅藻B38中氨基酸总量为852.58 mg/g,必需氨基酸占总氨基酸的47.45%,必需氨基酸指数为85.42%。两种模式的氨基酸比值系数分较接近,均在65以上;待评价物质的氨基酸品质与模式蛋白的贴近度接近1(0.93和0.88)。栅藻B38中共检测出23种矿物质元素,其中钠、钾、钙、镁、铁、铝含量较为丰富。重金属的含量均低于国家食品卫生标准。栅藻B38中维生素B3(106.02 mg/100 g)和维生素E(540.77 mg/100 g)的量较高。综上,栅藻B38的营养较丰富,可以进一步开发利用。  相似文献   
12.
通过给牦牛投喂硫酸头孢喹肟(CEF)、盐酸二氟沙星(DIF)和黄曲霉毒素B1(AFB1),并进行瘤胃微生物宏基因组测序,旨在揭示这3种外源性刺激因子对抗生素抗性基因(ARGs)种类、抗性类型、抗性机制等的影响,对于深入研究微生物抗性组特征和抗性机制具有重要价值。选取15头牦牛,随机分5组。Cef组和Dif组分别根据说明书推荐剂量按体重计算、灌服CEF 1 mg·kg^-1和DIF 1 mL·kg^-1;E1组和E2组分别按采食量投喂AFB120、60μg·kg^-1;C组为对照组。处理7 d后,采集瘤胃液,提取DNA,Illumina HiSeq测序,对reads counts进行标准化得到TPM值,并进行方差分析。结果显示,对照组共获得132种ARGs,分属30种抗性类型,其中,四环素类tetQ和tetW基因丰度较高;Cef组tetW基因丰度增加(P<0.05),Dif组tetQ丰度增加(P<0.05);Cef组四环素类和头孢菌素类抗性基因丰度增加(P<0.05),Dif组四环素类和氨基香豆素类抗性基因丰度增加(P<0.05),E1组氨基香豆素和青霉烯类抗性基因丰度增加(P<0.05),E2组青霉烯类、头孢菌素类等9类抗性基因丰度均增多(P<0.05);Dif组Erm基因23S核糖体RNA甲基转移酶丰度增加(P<0.05),E2组中ATP结合盒超家族等3种抗性机制相关基因的丰度增加(P<0.05);3种因子均显著增加四环素类ARGs宿主的种类。结论:瘤胃是蕴含丰富ARGs的储藏库,其中,四环素类抗生素抗性基因tetQ和tetW是主要的ARGs。不仅CEF和DIF使部分ARGs的种类、抗性类型以及耐药机制相关酶等的丰度升高,增加瘤胃微生物的耐药性,而且AFB1也具有类似作用,且高剂量AFB1对抗性类型的影响范围较抗生素大。这3种因子还导致携带四环素类ARGs宿主微生物的种类数量增加,从而强化横向转移机制,加快ARGs传播,增强微生物对四环素类的耐药性。  相似文献   
13.
This study aimed to investigate the protective effects and underlying mechanism of seaweed polysaccharide (SWP) on intestinal epithelial barrier dysfunction induced by E. coli in an IPEC-J2 model. A preliminary study was done to screen optimum SWP concentrations by cell viability, cytotoxicity, apoptosis and proliferation evaluation. The regular study was conducted to evaluate the protective effects of SWP against E. coli challenge via the analysis of transepithelial electrical resistance (TEER), tight junction proteins, NF-κB signalling pathway, proinflammatory cytokines and the E. coli adhesion and invasion. Our results show that 4 h E. coli challenge down-regulated tight junction proteins expression, decreased TEER, activated NF-κB signalling pathway and increased proinflammatory response, which indicates that the E. coli infection model was well-established. Pre-treatment with 240 μg/ml SWP for 24 h alleviated the 4 h E. coli -induced intestinal epithelial barrier dysfunction, as evidenced by the up-regulated expression of Occludin, Claudin-1 and ZO-1 at both mRNA and protein level and the increased TEER of IPEC-J2 cells. Pre-incubation with 240 μg/ml SWP for 24 h inhibited the activation of the NF-κB signalling pathway by 4 h E. coli challenge, including the decreased mRNA expression of TLR-4, MyD88, IκBα, p-65, as well as the reduced ratio of protein expression of p-p65/p65. Also, pre-treatment with 240 μg/ml SWP for 24 h decreased proinflammatory response (IL-6 and TNF-α) induced by 4 h E. coli challenge and decreased the E. coli adhesion and invasion. In conclusion, SWP mitigated intestinal barrier dysfunction caused by E. coli through NF-κB pathway in IPEC-J2 cells and 240 μg/ml SWP exhibited better effect. Our results also provide a fundamental basis for SWP in reducing post-weaning diarrhoea of weaned piglets, especially under E. coli -infected or in-feed antibiotic-free conditions.  相似文献   
14.
The aim of this study was to analyse the association between single-nucleotide polymorphisms within INHA and ACVR2B and litter size in Dazu black goats. In total, twenty-two SNPs were genotyped in 190 individuals by SNaPshot and resequencing. The results showed that three SNPs (SNP_1, SNP_12 and SNP_13 in this study) were detected to have significant additive genetic effect on the recorded goat litter size (p < .05). The SNP_1 (NC_030809.1), a non-synonymous substitution of G for T at chr2-g. 28314990 in the exon 2 of INHA gene (NM_001285606.1), resulted in homozygote 2 (HOM2) contributed 0.25 and heterozygote (HET) contributed 0.12 larger litter than homozygote 1 (HOM1). Meanwhile, SNP_12 (Chr22-g. 11721225 A > T) and SNP_13 (Chr22-g. 11721227 A > C) (NC_030829.1) simultaneously mutated at the first and third position of a triplet AAA (lysine, K) in the exon 4 of ACVR2B gene (XM_018066623.1) had estimated genetic effects of HOM1 (0.00) and HOM2 (0.03) larger than HET (−0.12). In conclusion, one SNPs (chr2-g. 28314990 T > G) within the exon 2 of INHA and two SNPs (Chr22-g. 11721225 A > T and Chr22-g. 11721227 A > C) i n the exon 4 of ACVR2B gene were highly recommended as candidate markers of litter size in Dazu black goats. A large-scale association study to assess the impact of these variants on litter size is still necessary.  相似文献   
15.
AIM:To investigate the protective effect of ethanol extract from Cortex Albiziae on acute liver injury, and to explore its possible mechanism. METHODS:Acute liver injury in mice was induced by single intraperitoneal injection of 25% carbon tetrachloride (olive oil solubilization). The effective parts of ethanol extract from Cortex Albizziae against acute liver injury were screened. The pathological changes of the liver tissues were examined by pathological sections with HE staining. The activity of total superoxide dismutase (T-SOD) and the content of malondialdehyde (MDA) of the liver tissues were detected, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were mea-sured by ELISA, and the protein expression levels of NF-κB p65, Bcl-2 and Bax in the liver cells of the mice in each group were determined by Western blot. RESULTS:Compared with model group, the serum levels of AST and ALT in low-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-L, 4 mg·kg-1·d-1) group and high-dose n-butanol phase of ethanol extract from Cortex Albiziae (AB-H, 8 mg·kg-1·d-1) group were significantly decreased. The necrosis extent and degree of the hepatocytes and infiltration of inflammatory cells were significantly lower than that in model group. Compared with model group, the serum levels of TNF-α and IL-6 in AB-H group and AB-L group were significantly decreased (P<0.05). The protein level of NF-κB p65 in the nuclei of mouse liver cells in AB-H group and AB-L group were also decreased significantly (P<0.05). Compared with model group, the protein expression of Bax was decreased, the protein expression of Bcl-2 was increased, and the Bcl-2/Bax ratio was increased in AB-L group and AB-H group. CONCLUSION:The n-butanol phase of ethanol extract from Cortex Albiziae may protect the liver by reducing the activation of NF-κB p65, inhibiting the excessive release of inflammatory cytokines IL-6 and TNF-α, and decreasing hepatocyte apoptosis via regulating Bcl-2 and Bax expression.  相似文献   
16.
AIM: To investigate the role of Toll-like receptor 4 (TLR4) and transient receptor potential channel 6 (TRPC6) signaling pathway in lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) P65 expression and nuclear translocation in airway epithelial cells (16HBE) for supplementing the mechanism for airway inflammation. METHODS: After stimulating the 16HBE cells with LPS at 1 mg/L for 0, 0.5, 2, 6, 12 and 24 h, the expression of NF-κB P65 at mRNA and protein levels in the 16HBE cells were determined by RT-PCR and Western blot respectively, and the nuclear translocation of NF-κB P65 was detected by immunocytochemical staining method. The effects of TLR4 inhibitor CLI-095 at 5 μmol/L and TRPC6 agonist Hyp9 at 10 μmol/L on LPS (1 mg/L)-induced NF-κB P65 expression and nuclear translocation in the 16HBE cells were determined by RT-PCR, Western blot and immunocytochemical staining. RESULTS: LPS increased the mRNA and protein expression of NF-κB P65 and nuclear translocation in the 16HBE cells(P<0.05). TLR4 inhibitor CLI-095 reduced the mRNA and protein expression of NF-κB P65 and nuclear translocation induced by LPS, while Hyp9 enhanced the mRNA and protein expression of NF-κB P65 and nuclear translocation induced by LPS in the 16HBE cells(P<0.05). CONCLUSION: LPS induces the expression and nuclear translocation of NF-κB P65 in the 16HBE cells via TLR4-TRPC6 signaling pathway.  相似文献   
17.
NMB/NMBR通过调节A型流感病毒(IAV/H1N1/PR8)感染诱导的细胞因子表达而参与抗IAV的先天性免疫反应。为探究其发挥抗IAV/H1N1感染的信号通路,本文用PR8和WSN毒株分别感染MLE-12细胞和小鼠,用NF-κB抑制剂BAY11-7028单独或联合NMB处理MLE-12细胞,小鼠后腿肌内注射NMB和NMBRA,采用RT-PCR和qRT-PCR分析NMBNMBRIL-6、IFN-α和NP基因表达变化,采用Western blot分析NMB、NMBR、P65/p-P65、IκBα和NP蛋白表达的变化。结果显示,BAY11-7028可促使PR8和WSN感染的MLE-12细胞中NMB、NMBRIL-6和IFN-α基因表达水平均下降和NP基因表达水平上升,并降低NMB、NMBR和p-P65蛋白表达水平和提升IκBα和NP蛋白表达水平。然而,NMB联合BAY 11-7028诱导PR8或WSN感染后的细胞中IL-6和NP表达出现极显著下降和IFN-α显著上升。此外,NMB抑制PR8和WSN感染的小鼠肺组织内p-P65和NP蛋白表达水平和促进IκBα蛋白表达水平;NMBRA联合NMB抵消NMB对PR8或WSN感染后的这些蛋白表达水平的调节作用。综上表明,NMB/NMBR通过调节PR8和WSN感染的MLE-12细胞和小鼠体内的NF-κB信号通路上P65蛋白磷酸化和IκBα的表达,进而影响下游细胞因子IL-6和IFN-α基因的表达,从而发挥抗IAV/H1N1感染的先天性免疫应答反应。  相似文献   
18.
Single nucleotide polymorphisms (SNPs) of cytokine genes have been found to be involved in the clinical outcome of Tuberculosis. The present study was aimed to identify the high risk genotypes in Tuberculosis patients and their household contacts. A total of 490 subjects were studied which includes 150 active pulmonary tuberculosis patients (APTB), 190 household contacts (HHC) and 150 healthy controls (HC). The SNPs of TNF-α (-308A/G), IL-10(-1082G/A) and IL-6(-174G/C) were performed by ARMs PCR. The IL-10 GA genotype showed significant association in APTB and HHC and was 2.3 times higher risk in APTB and 3.7 times in HHC compared to HCs. The A allele was found to be significantly associated with the risk of disease. The CC genotype of IL-6 was found to be significantly associated in APTB and an insignificant positive association in HHCs. The multifactor dimensionality reduction (MDR) analysis indicated that the genotypes of IL-6 were showing high risk with GA genotype of IL-10. In conclusion the gene interaction may be useful for identification of genotypes as biomarkers to distinguish high risk individuals.  相似文献   
19.
以天维菌素B、天维菌素B单糖苷和天维菌素B苷元为原料,经选择性C-5羟基保护,在C-13、C-4′和C-4″位引入不同酰基基团,合成了3个系列共23个天维菌素B酰化衍生物,并通过1H NMR、13C NMR和高分辨质谱对所有目标化合物的结构进行了表征。生物活性测定结果表明,所有衍生物对小菜蛾Plutella xylostella、朱砂叶螨Tetranychus cinnabarinus以及松材线虫Bursaphelenchus xylophilus均表现出不同程度的毒杀活性,其中天维菌素B C-4″位衍生物的活性优于C-4′位衍生物及13位衍生物。化合物8e对小菜蛾和松材线虫的毒杀活性最优,LC50值分别为9.2 mg/L和0.42 mg/L,化合物8b对朱砂叶螨的毒性最高,LC50值为0.0019 mg/L,均优于对照药天维菌素B。  相似文献   
20.
AIM: To investigate the expression and roles of family with sequence similarity 3, member C (FAM3C) in oral squamous-cell carcinoma cells. METHODS: The mRNA and protein expression levels of FAM3C in dysplastic oral keratinocyte (DOK) and oral squamous-cell carcinoma WSU-HN6 cells were detected by RT-qPCR and Western blot. The WSU-HN6 cells were treated with siFAM3C or FAM3C antibody. After 24, 48 and 72 h, the viability of WSU-HN6 cells was measured by CCK-8 assay, and the activation of protein kinase B (Akt) was detected by Western blot. Adenovirus was used to mediate over-expression of FAM3C in the DOK cells. The DOK cell viability was measured by CCK-8 assay after adenovirus infection for 24, 48 and 72 h, and the activation of Akt was detected by Western blot. RESULTS: Compared with the DOK cells, the mRNA and protein levels of FAM3C were significantly increased in the WSU-HN6 cells (P<0.05). The viability of WSU-HN6 cells transfected with siFAM3C was significantly inhibited at 48 h and 72 h (P<0.05). siFAM3C treatment inhibited the activation of Akt (P<0.05). FAM3C antibody treatment also suppressed the viability of the WSU-HN6 cells at 48 h and 72 h and the activation of Akt (P<0.05). Over-expression of FAM3C in the DOK cells promoted the cell viability at 48 h and 72 h and activated Akt (P<0.05). CONCLUSION: FAM3C might promote oral squamous-cell carcinoma cell growth by activating Akt.  相似文献   
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