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81.
Tau is the most abundant microtubule-associated protein in the brain. If tau protein lost the normal function, the toxic effect should be showed and plays an important role in various central nervous system lesions. Hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality in the neonatal period and it is mainly characterized by neurological deficits such as cognitive limitations. However, the mechanism still needs further study, and the underlying relationship between tau protein and HIE lacks direct evidence. Some recent clinical study reported that tau protein expression elevated in the serum of asphyxia children and had a high correlation with behavior deficient. In this review, we focus on 3 key points to provide new insights to understand the tau protein-related pathogenesis of HIE as followed: (1) tau protein and its phosphorylation change during central nervous system development; (2) comparison of tau protein expression in developing brain and adult brain under some neurological disorders; (3) potential pathological change of tau in HIE related pathological conditions, such as dysmyelination, inflammation response and glutamate metabolism. 相似文献
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本试验旨在研究不同浓度降钙素基因相关肽(CGRP)对猪小肠上皮细胞钠离子依赖型Ⅱb磷转运蛋白(NaPi-Ⅱb)表达和磷吸收的影响.选用第3~8代猪小肠上皮细胞进行试验,按单因素试验设计,将试验细胞分为1个对照组和5个CGRP(1×10-11~1×10-7 mmol/L)试验组,每组设6个重复.用4-甲基偶氮唑盐(MTT)法测定细胞生长速度,采用比色法测定CGRP干预24 h后细胞上清液磷含量,用RT-PCR法检测NaPi-Ⅱb mRNA相对表达量,以及蛋白质印迹(Western blot)法检测NaPi-Ⅱb蛋白表达.结果表明:与对照组相比,不同浓度CGRP对细胞生长没有显著影响(P>0.05);各试验组均极显著或显著地促进了磷的吸收和NaPi-ⅡbmRNA的相对表达量(P<0.01或P<0.05);除1×10-10 mmol/L组外均显著提高了NaPi-Ⅱb蛋白的表达(P<0.05).研究结果表明,CGRP通过诱导小肠上皮细胞中NaPi-Ⅱb的表达促进细胞磷的吸收,其中以1×10-9、1×10-8 mmol/L浓度的CGRP促进效果较为显著. 相似文献
84.
为研究从碎米花杜鹃叶中分离得到的化合物原花青素A-1(Proanthocyanidin A-1,简称PAA-1)的免疫增强活性,初步从细胞水平上探讨其免疫增强机制。体外试验采用流式细胞术,检测PAA-1体外对小鼠脾淋巴细胞T细胞亚群CD4和CD8单阳性和双阳性T淋巴细胞亚群百分率及CD4+/CD8+比值;体内试验通过饲喂不同剂量的PAA-1后,检测试验猪外周血淋巴细胞CD4和CD8单阳性以及CD4+/CD8+比值。结果证明,体外试验中同阴性对照组相比,PAA-1能单独或协同Con A提升具CD4+、CD8+及CD4+CD8+表型的T淋巴细胞亚群百分率,提高CD4+/CD8+的比值;体内试验中饲喂中、高剂量的PAA-1的试验猪外周血中具有CD4+、CD8+表型的T淋巴细胞的百分率及CD4+/CD8+的比值均有显著提高。说明PAA-1可通过增加辅助性T淋巴细胞和细胞毒性T淋巴细胞数量、促进T淋巴细胞的成熟以及增加CD4+/CD8+的比值发挥增强细胞免疫的作用,为其进一步开发为新型免疫增强剂提供试验依据。 相似文献
85.
2015-2016年对来自黑龙江地区46个养殖场送检的鲤鱼进行锦鲤疱疹病毒(Koi herpes virus,KHV)的分离鉴定,并应用DNAStar等软件对检出的阳性样本的主要囊膜蛋白(Major envelop protein,MEP)基因进行生物信息学分析。结果显示,KHV的检出率约为6.5%,3株阳性样本具有相同的MEP基因序列,称之为KHV-HLJ1516。MEP基因开放阅读框为771 bp,编码256个氨基酸,相对分子质量为28 280.58,等电点为8.40。对KHV-HLJ1516的MEP基因序列同源性分析表明,其与KHV-GZ11分离株仅有1个碱基不同,但并未导致氨基酸发生改变,碱基相似性为99%;而与HZ419分离株相比,KHV-HLJ1516的MEP基因有3个碱基发生突变,相应的氨基酸由Asn变为IIe。聚类分析结果显示,KHV-HLJ1516与KHV-GZ11处于同一分支,而HZ419位于另一分支。B细胞抗原表位预测结果显示,KHV-HLJ1516的MEP的抗原表位主要位于4~11,24~40,42~63,82~110,209~218,238~249氨基酸区段。 相似文献
86.
Antioxidant and anti‐inflammatory activities of Pinus radiata bark extract in salmonid cell lines 下载免费PDF全文
Allisson Astuya Javiera Ziehe Alejandra Rivera Sebastián Ortiz Viviana Ulloa Marlene Roeckel Estrella Aspé Katherina Fernández 《Aquaculture Research》2017,48(7):3568-3578
A fish meal supply shortage is limiting aquaculture development. Currently, plant‐based proteins, such as soya bean meal, are being used as an alternative protein source, despite that such a diet can adversely affect fish, such as by inducing an inflammatory response. A possible solution is to include dietary additives in farm diets to counteract negative effects. One such solution originates from pine bark extracts, which present bioactive properties. In this study, the antioxidant and anti‐inflammatory properties of Pinus radiata bark extracts were evaluated for the first time in a salmonid cell line. This extract chemically demonstrated antioxidant activity through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH = 58.4 ± 1.1%) and ferric ion reducing antioxidant power (FRAP = 575 ± 17 mgEqFe(II)·g extract?1) assays. Additionally, the extract showed high flavonoid and phenolic compound contents. Up to 100 mg mL?1, the P. radiata extract showed no cytotoxicity in the CHSE‐214 salmonid embryo cell line. Moreover, the antioxidant activity of the extract (50 μg mL?1) was evaluated by a dichlorofluorescein (DCFH) assay in the SHK‐1 salmon cell line challenged with an oxidant stimulus (H2O2), showing 58.9% activity. The extract also protected DNA from oxidative damage, as observed through a comet assay. When assessing anti‐inflammatory properties in an in vitro inflammation model, the extract significantly reduced the relative expression of the pro‐inflammatory cytokines interleukin‐1β (IL‐1β), tumour necrosis factor‐α (TNF‐α) and interleukin‐8 (IL‐8) and of the inducible cyclooxygenase‐2 (COX‐2) enzyme. These results suggest a potential application of P. radiata bark extract in functional foods in aquaculture. 相似文献
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88.
Legislation limiting the use of chlorpropham (CIPC), the major potato sprout suppressant, has led to a need for new technologies to extend storage life of tubers. Ultra violet C (UV-C) has been used postharvest to reduce disease incidence on many crops, yet its use and efficacy as a sprout suppressant has not been investigated. The aim of this project was to identify the optimum dose and treatment timing of UV-C treatment on potato tubers as an alternative method of sprout suppression to reduce the dependence on chemical sprout suppressants. Up to six potato cultivars over two seasons were treated with varying doses of UV-C ranging from 0 to 30 kJ m−2 either at harvest or at first indication of dormancy break. The tubers were stored at 9 °C and sprout growth and incidence assessed. Treatment with moderate UV-C doses (5–20 kJ m−2) suppressed sprout length and sprout incidence in a range of cultivars. Periderm DNA damage and programmed cell death were not detected in response to any of the UV-C doses. The inactive ABA metabolite, ABA-GE, increased in response to 10 or 20 kJ m−2 within 72 h of treatment. Multivariate analysis showed a negative relationship between ABA metabolites and sprout growth/incidence during storage. This study found that UV-C reduced sprout growth in potato with no deleterious effects on tuber quality. This suggests potential for further development as an alternative or supplement to conventional sprout suppressant technologies. 相似文献
89.
Visible and near infrared (vis/NIR) spectroscopy combined with chemometrics were investigated to evaluate the effects of simulated transport vibration levels on damage of tomato fruit. A total of 280 tomato samples were randomly divided into 5 groups; each group was subjected to vibration at different acceleration levels. A total of 230 samples (46 from each group) were selected as a calibration set; whereas 50 samples (10 from each group) were selected as a prediction set. Raw spectra, differentiation (the first derivative) spectra, extended multiplicative scatter correction (EMSC) processed spectra and standard normal variant combined with detrending (SNV–DT) processed spectra were used for calibration models. SNV–DT processed spectra had the best performance using for partial least squares (PLS) analysis. The PLS analysis was implemented to calibrate models with different wavelength bands including visible, short-wave near infrared (SWNIR) and long-wave near infrared (LWNIR) regions. The best PLS model was obtained in the vis/NIR (600–1600 nm) region. Using a grid search technique and radial basis function (RBF) kernel, four least squares support vector machine (LS–SVM) models with different latent variables (7, 8, 9, and 10 LVs) were compared. The optimal model was obtained with 9 LVs and the correlation coefficient (r), root mean square error of prediction (RMSEP) and bias for the best prediction by LS–SVM were 0.984, 0.137 and 0.003, respectively. The results showed that vis/NIR spectroscopy could be applied as a reliable and rapid method for predicting the effect of vibration levels on tissue damage of tomato fruit. 相似文献
90.
FGF4已经被证明是癌基因,它涉及肿瘤的生长和转移,为了解FGF4的表达与肿瘤微环境的关系。我们利用FGF4抗体通过免疫组化对一名肺癌患者癌旁,癌组织,癌组织小鼠移植瘤,二次移植瘤以及原代培养的细胞爬片进行FGF4检测,探究其表达差异。通过对比癌组织与对照组(癌旁组织),FGF4在癌巢中高表达;同样,移植瘤与二次移植瘤的癌巢中与癌旁组织比较,FGF4表达相对较高;但是将癌组织进行原代培养后,免疫组化检测细胞爬片FGF4,发现仅有5%±0.21%的肿瘤细胞表达FGF4,对照蛋白Cytokine作为肿瘤标记物,则在100%的肿瘤细胞中表达。研究提示免疫组化检测到FGF4在体内和体外表达不同,提示肿瘤细胞FGF4的表达与肿瘤微环境调控密切相关,肿瘤微环境对肿瘤细胞的FGF4的调控有着重要作用。 相似文献