NM23-H1、 DJ1 和 TIM1 在低分化鼻咽鳞癌 组织和 CNE2 细胞株中共同表达

鼻咽癌为一种好发于鼻咽顶前壁及咽隐窝的头颈肿瘤, 98% 属低分化鳞癌 . 鼻咽癌就诊的患者中约 75% 已有颈淋巴结转移,颅神经受累 ( Ⅱ ~ Ⅵ, Ⅸ ~ Ⅻ ) 也较易发生. CNE2 为一种低分化鼻咽鳞癌细胞系,其生物学行为具有低分化鼻咽鳞癌的一些共同特点 . 选择恶性程度高的鼻咽癌组织 ( Ⅳ期,低分化鼻咽鳞癌 ) 和恶性程度高的低分化鼻咽鳞癌细胞株 CNE2 为研究样本,应用双向凝胶电泳技术获得了 6 例分辨率较高、重复性较好的低分化鼻咽鳞癌组织和 CNE2 细胞系双向凝胶电泳图谱,利用基质辅助激光解吸电离飞行时间质谱 (MALDI-TOF-MS) 技术,分析了 145 个蛋白质斑点 ( 组织 66 个点,细胞株 79 个点 ),共鉴定出了 74 种蛋白质,其中瘤基因 DJ1、转移相关基因 NM23-H1 和磷酸丙糖激酶异构酶 1(TIM1) 3 种蛋白质,在 CNE2 细胞系和该 6 例低分化鼻咽鳞癌组织中均共同表达 . 并进一步应用 RT-PCR 法检测低分化鼻咽鳞癌细胞系 CNE2 和 12 例低分化鼻咽鳞癌组织三者 mRNA 的表达：在细胞系 CNE2 和 3 例Ⅳ期低分化鼻咽鳞癌病人的组织中三者全表达, 3 例Ⅲ期及 6 例Ⅱ期也各有 1 例为全表达,而在正常对照的 6 例慢性鼻咽炎组织中未检测到三者的同时表达且有一例为全阴性, NM23-H1、 DJ1 和 TIM1 三者的 mRNA 在Ⅲ、Ⅳ期低分化鼻咽鳞癌组织共同表达,与正常对照组织相比,发现两者有显著性差异 (x²=10.214 , P＜0.005). NM23-H1、 DJ1 和 TIM1 三者的共同表达,可能与低分化鼻咽鳞癌的发生发展有关.     

EGFR/MET promotes hepatocellular carcinoma metastasis by stabilizing tumor cells and resisting to RTKs inhibitors in circulating tumor microemboli

The receptor tyrosine kinases (RTKs) family is well-recognized as vital targets for the treatment of hepatocarcinoma cancer (HCC) clinically, whereas the survival benefit of target therapy sorafenib is not satisfactory for liver cancer patients due to metastasis. EGFR and MET are two molecules of the RTK family that were related to the survival time of liver cancer patients and resistance to targeted therapy in clinical reports. However, the mechanism and clinical therapeutic value of EGFR/MET in HCC metastasis are still not completely clarified. The study confirmed that EGFR/MET was highly expressed in HCC cells and tissues and the phosphorylation was stable after metastasis. The expression of EGFR/MET was up-regulated in circulating tumor microemboli (CTM) to accelerate IL-8 production and resistance to the lethal effect of leukocytes. Meanwhile, highly expressed EGFR/MET effectively regulated the Ras/MAPK pathway and stabilized suspended HCC cells by facilitating proliferation and inhibiting apoptosis. Moreover, EGFR/MET promoted phosphorylation of hetero-RTKs, which was dependent on high-energy phosphoric acid compounds rather than their direct interactions. In conclusion, highly expressed EGFR/MET could be used in CTM identification and suitable for preventing metastasis of HCC in clinical practice.Subject terms: Liver cancer, Metastasis     

Amperometric glucose biosensor based on self-assembly hydrophobin with high efficiency of enzyme utilization

Hydrophobins are a family of natural self-assembling proteins with high biocompability, which are apt to form strong and ordered assembly onto many kinds of surfaces. These physical-chemical and biological properties make hydrophobins suitable for surface modification and biomolecule immobilization purposes. A class II hydrophobin HFBI was used as enzyme immobilization matrix on platinum electrode to construct amperometric glucose biosensor. Permeability of HFBI self-assembling film was optimized by selecting the proper HFBI concentration for electrode modification, in order to allow H₂O₂ permeating while prevent interfering compounds accessing. HFBI self-assembly and glucose oxidase (GOx) immobilization was monitored by quartz crystal microbalance (QCM), and characterization of the modified electrode surface was obtained by scanning electron microscope (SEM). The resulting glucose biosensors showed rapid response time within 6 s, limits of detection of 0.09 mM glucose (signal-to-noise ratio = 3), wide linear range from 0.5 to 20 mM, high sensitivity of 4.214 × 10⁻³ A M⁻¹ cm⁻², also well selectivity, reproducibility and lifetime. The all-protein modified biosensor exhibited especially high efficiency of enzyme utilization, producing at most 712 μA responsive current for per unit activity of GOx. This work provided a promising new immobilization matrix with high biocompatibility and adequate electroactivity for further research in biosensing and other surface functionalizing.     

The histone demethylases Jhdm1a/1b enhance somatic cell reprogramming in a vitamin-C-dependent manner

Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) resets the epigenome to an embryonic-like state. Vitamin C enhances the reprogramming process, but the underlying mechanisms are unclear. Here we show that the histone demethylases Jhdm1a/1b are key effectors of somatic cell reprogramming downstream of vitamin C. We first observed that vitamin C induces H3K36me2/3 demethylation in mouse embryonic fibroblasts in culture and during reprogramming. We then identified Jhdm1a/1b, two known vitamin-C-dependent H3K36 demethylases, as potent regulators of reprogramming through gain- and loss-of-function approaches. Furthermore, we found that Jhdm1b accelerates cell cycle progression and suppresses cell senescence during reprogramming by repressing the Ink4/Arf locus. Jhdm1b also cooperates with Oct4 to activate the microRNA cluster 302/367, an integral component of the pluripotency machinery. Our results therefore reveal a role for H3K36me2/3 in cell fate determination and establish a link between histone demethylases and vitamin-C-induced reprogramming.     

用荧光标记O-I噬菌体快速检测食品源沙门氏菌

[目的]利用O-I噬菌体几乎可裂解沙门氏菌属细菌的特性建立快速检测食品中沙门氏菌的方法.[方法]用核酸荧光染料SYBR gold染料标记O-I噬菌体侵染100株试验菌及120份食品样品菌,荧光显微镜鉴定沙门氏菌;并测灵敏度.[结果]100株试验菌中40株沙门氏菌可见杆状荧光,而10株变形杆菌、20株志贺氏菌、20株大肠杆菌和10株葡萄球菌均无荧光;沙门氏菌检测灵敏度达10 CFU/100 μL;120份食品样品中沙门氏菌的O-I噬菌体检测与生化鉴定结果的阳性率分别为9.17%和10%,符合率为91.7%.[结论]试验表明用荧光标记的O-I噬菌体可以快速、直观、准确、大量地检测食品中沙门氏菌.     

Methylation-mediated miR-214 regulates proliferation and drug sensitivity of renal cell carcinoma cells through targeting LIVIN

LIVIN, a member of the inhibitor of apoptosis proteins (IAPs), is reported playing important roles in the development and progression of multiple human cancers. However, its underlined mechanisms in human renal cell carcinoma (RCC) are still needed to be clarified. In the present study, we reported that inhibition of miR-214 promoted the expression of LIVIN, then facilitated RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs. In constant, overexpression of miR-214 had contradictory effects. Further investigation showed that miR-214 was down-regulated in RCC because of abnormal methylation. In addition, DNA methyltransferase DNMT1, miR-214 and LIVIN are directly correlated in RCC patients. In conclusion, these results suggest that abnormal miR-214 methylation negatively regulates LIVIN, which may promote RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs.     

Effects of Dietary Iodine and Selenium on Nutrient Digestibility,Serum Thyroid Hormones,and Antioxidant Status of Liaoning Cashmere Goats

Forty-eight 2-year-old Liaoning Cashmere goats (body weight = 38.0 ± 2.94 kg) were used to investigate the effects of dietary iodine (I) and selenium (Se) supplementation on nutrient digestibility, serum thyroid hormones, and antioxidant status during the cashmere telogen period to learn more about the effects of dietary I and Se on nutrition or health status of Cashmere goats. The goats were equally divided into six groups of eight animals each that were treated with 0, 2, or 4 mg of supplemental I/kg dry matter (DM) and 0 or 1 mg of supplemental Se/kg DM in a 2 × 3 factorial arrangement of treatments. The six treatments were I₀Se₀, I₂Se₀, I₄Se₀, I₀Se₁, I₂Se₁, and I₄Se₁. The concentrations of I and Se in the basal diet were 0.67 and 0.09 mg/kg DM, respectively. The study started in March and proceeded for 45 days. Supplemental I or Se alone had no effect on nutrient digestibility and nitrogen metabolism. However, the interaction between I and Se was significant regarding the digestibility of acid detergent fiber (ADF; P < 0.05), and compared with group I₄Se₁, the digestibility of ADF was significantly increased in group I₄Se₀ (P < 0.05). Selenium supplementation did not affect serum triiodothyronine (T₃) or thyroxine (T₄) concentrations. However, the concentration of serum T₄ but not that of T₃ was significantly increased with I supplementation (P < 0.05). In addition, serum superoxide dismutase (SOD) activity was not affected (P > 0.05), but serum glutathione peroxidase (GSH-Px) activity was significantly decreased by I supplementation (P < 0.05). The antioxidant status was improved by Se supplementation, and the activities of SOD and GSH-Px were significantly increased (P < 0.05).     

广西防城港黑翅长脚鹬的繁殖行为

本研究于2021年3～9月,采用目标观察和全事件记录法,对广西防城港市钦州湾八路水湿地黑翅长脚鹬（Himantopus himantopus）的繁殖习性进行全过程观察记录。黑翅长脚鹬的栖息生境主要在盐田、虾塘和鱼塘,而巢主要分布在盐田生境。共发现39巢,雌雄共同营巢,按照主要巢材将其巢分为干草巢、碎石巢、泥皮巢和牛毛毡草巢4种;巢材包括禾本科（Gramineae）和莎草科（Cyperaceae）植物以及碎石、贝壳等;巢外径为（23.3±10.7）cm,巢内径为（11.2±1.9）cm,巢深为（1.6±0.5）cm,巢高为（6.5±4.3）cm(n=39);筑巢需（3±2）d(n=6)。窝卵数2～4枚,1～2 d产1枚卵,7 d内产完满窝卵（n=6）。雌雄均参与孵卵,雄性孵卵时间比雌性长,但二者差异不显著（P> 0.05）,雄性（8 550±245.9）min,雌性（7 530±263.3）min,孵卵期为（25±2）d(n=6)。育雏期（26±3）d(n=6),雌雄轮流育雏,育雏前、中期（雏鸟1～20d日龄）,雌性育雏时间比雄性长,是雄性的2倍,育雏后期（雏鸟大于20 d日龄）,...     

镉吸附细菌的分离及其对土壤镉的固定

[目的] 探究镉吸附细菌是否能够高效固定土壤有效镉（Cd）,为土壤有效Cd的微生物固定提供理论依据。[方法] 利用含Cd²⁺牛肉膏蛋白胨液体培养基对细菌进行Cd的耐受性测试筛选出镉抗性强的菌株;通过16S rRNA基因相似性及系统进化分析鉴定耐镉细菌,将菌细胞加入含CdCl₂溶液中进行Cd²⁺吸附效率测定;通过土培模拟实验,测定土壤pH、碱解氮、有效磷、速效钾、有机质、CEC、有效Cd及微生物数量来分析镉吸附细菌对镉污染土壤的影响。[结果] 从德阳鱼腥草根际土壤中分离获得的57株细菌对Cd²⁺表现出不同程度的抗性,并从中筛选出3株耐Cd优势细菌普罗威登斯菌属（Providencia）DY8、芽孢杆菌属（Bacillus）DY3和芽孢杆菌属（Bacillus）DY1-4。其对溶液中的Cd²⁺表现出较好的吸附作用,吸附效率随着Cd²⁺浓度升高而降低。DY8、DY3、DY1-4能使镉污染土壤中有效Cd含量分别降低72.11%、68.55%、62.32%,同时显著提高镉污染土壤中碱解氮、有效磷的含量。[结论] Cd污染农田土壤中含有丰富的耐Cd微生物资源,Cd吸附细菌能降低土壤中有效Cd的含量,且能有效改善土壤养分条件。     

Comprehensive gene and microRNA expression profiling reveals the crucial role of hsa-let-7i and its target genes in colorectal cancer metastasis

Accumulating evidence has demonstrated that miRNAs play important roles in the occurrence and development of colorectal cancer (CRC). However, whether miRNAs are associated with the metastasis of CRC remains largely unexplored. The aim of the current study is to profile miRNAs in different CRC metastatic cell lines to identify the biomarkers in CRC metastasis. Gene and miRNA expression profiling was performed to analyze the global expression of mRNAs and miRNAs in the four human CRC cell lines (LoVo, SW480, HT29 and Caco-2) with different potential of metastasis. Expression patterns of mRNAs and miRNAs were altered in different CRC cell lines. By developing an integrated bioinformatics analysis of gene and miRNA expression patterns, hsa-let-7i was identified to show the highest degree in the microRNA-GO-network and microRNA-Gene-network. The expression level of hsa-let-7i was further validated by qRT-PCR in CRC cells. In addition, the targets of hsa-let-7i were predicted by two programs TargetScan and PicTar, and target genes were validated by expression profiling in the most epresentative LoVo and Caco-2 cell lines. Eight genes including TRIM41, SOX13, SLC25A4, SEMA4F, RPUSD2, PLEKHG6, CCND2, and BTBD3 were identified as hsa-let-7i targets. Our data showed the power of comprehensive gene and miRNA expression profiling and the application of bioinformatics tools in the identification of novel biomarkers in CRC metastasis.