MicroRNA-30a sensitizes tumor cells to cis-platinum via suppressing beclin 1-mediated autophagy

Autophagy is activated in cancer cells during chemotherapy and often contributes to tumor chemotherapy resistance. In this study, we characterized the role of microRNA-30a (miR-30a) in the coordination of cancer cell apoptosis and autophagy, which determines the sensitivity of cancer cells to chemotherapy. First, the autophagy activity in cancer cells increased after cis-dichloro-diamine platinum (cis-DDP) or Taxol treatment, as indicated by the enhanced expression of beclin 1, a key regulator of autophagy, and increased number of LC3-positive autophagosomes. Second, miRNA screening using a TaqMan probe-based quantitative RT-PCR assay identified that miR-30a, a miRNA that targets beclin 1, was significantly reduced in tumor cells by cis-DDP treatment. Forced expression of miR-30a significantly reduced beclin 1 and the autophagy activity of tumor cells induced by cis-DDP. Third, the blockade of tumor cell autophagy activity by miR-30a expression or 3-methyladenine significantly increased tumor cell apoptosis induced by cis-DDP treatment. Finally, an in vivo tumor implantation mouse model clearly showed that elevation of miR-30a in implanted tumor cells by administration of the recombinant lentivirus expressing miR-30a strongly enhanced cis-DDP-induced apoptosis of tumor cells. In conclusion, our results demonstrate for the first time that miR-30a can sensitize tumor cells to cis-DDP via reducing beclin 1-mediated autophagy and that increasing miR-30a level in tumor cells represents a novel approach to enhance the efficacy of chemotherapy during cancer treatment.     

Tissue-engineered mesh for pelvic floor reconstruction fabricated from silk fibroin scaffold with adipose-derived mesenchymal stem cells

A tissue-engineered mesh fabricated with adipose-derived mesenchymal stem cells (AD-MSCs) cultured on a silk fibroin scaffold is evaluated for use in female pelvic reconstruction. Thirty-five female Sprague Dawley rats were divided into four groups. Group A (n?=?10) were implanted with polypropylene meshes, Group B (n?=?10) with silk fibroin scaffolds and Group C (n?=?10) with tissue-engineered meshes. Group D (n?=?5) acted as the tissue control. The tissue-engineered mesh was produced as follows. AD-MSCs were obtained from adipose tissue of rats designated to Group C. The cells were seeded onto a silk fibroin scaffold, cultured and then observed by scanning electron microscopy (SEM). Histological studies of these meshes were performed at 4 and 12 weeks after implantation and mechanical testing was carried out on all groups before implantation and at 12 weeks after implantation. AD-MSCs displayed fibroblast-like shapes and were able to differentiate into adipocytes or fibroblasts. SEM observation showed that AD-MSCs proliferated and secreted a matrix onto the silk fibroin scaffolds. After implantation of the scaffolds into rats, histological analysis revealed better organized newly formed tissue in Group C than in controls. Group C also had a similar failure force (2.67?±?0.15 vs 2.33?±?0.38 N) and a higher Young’s modulus (2.99?±?0.19 vs 1.68?±?0.20 MPa) than a normal vaginal wall, indicating the potential of this tissue-engineered approach. AD-MSCs were validated as seed cells for tissue engineering. The silk fibroin scaffold thus shows promise for application with AD-MSCs in the fabrication of tissue-engineered mesh with good biocompatibility and appropriate mechanical properties for pelvic floor reconstruction.     

Serum miR-128-2 Serves as a Prognostic Marker for Patients with Hepatocellular Carcinoma

Circulating miRNAs are promising biomarkers for predicting the aggressiveness of hepatocellular carcinoma (HCC). We aimed to identify differentially expressed miRNAs in the serum of HCC patients with different Barcelona Clinic Liver Cancer (BCLC) stage, and to investigate the potential of serum miRNAs as biomarkers for patient outcomes. In the discovery stage, TaqMan Low-Density Array was used to test the difference in levels of serum miRNAs between 20 patients with portal vein tumor thrombosis (PVTT) and 20 patients without PVTT. The detected serum miRNAs then were validated in 182 patients. Fifteen serum miRNAs showed more than two-fold higher expression in patients with PVTT, and miR-128-2 was found to be significantly up-regulated and was selected for further validation. In the validation stage, patients were divided into two groups with low or high serum miR-128-2 using the median expression level of all 182 cases as the cut-off point. Kaplan-Meier analysis revealed that patients with low level of serum miR-128-2 had favorable trends of survival (log rank = 13.031, p < 0.001). The median survivals for patients with a low and high level of serum miR-128-2 were 625 (95% CI, 527–722) days and 426 (95% CI, 362–491) days, respectively. MiR-128-2 was also an independent factor of overall survival (p = 0.001, HR 2.793, 95%CI 1.550, 5.033). Serum levels of the ubiquitously expressed miR-128-2 showed no significant correlation with parameters of liver damage or liver function. In addition, expressions of miR-128-2 in HCC tissues were up-regulated in comparison with adjacent non-tumor tissues. In conclusion, serum level of miR-128-2 serves as a noninvasive biomarker for the overall survival of patients with hepatocellular carcinoma.     

Production of β-xylosidase from <Emphasis Type="Italic">Trichoderma asperellum</Emphasis> KIF125 and its application in efficient hydrolysis of pretreated rice straw with fungal cellulase

On-site cellulase and hemicellulase production is a promising way to reduce enzyme cost in the commercialization of the lignocellulose-to-ethanol process. A hemicellulase-producing fungal strain suitable for on-site enzyme production was selected from cultures prepared using wet disc-milling rice straw (WDM-RS) and identified as Trichoderma asperellum KIF125. KIF125 hemicellulase showed uniquely high abundance of β-xylosidase in the xylanolytic enzyme system compared to other fungal hemicellulase preparations. Supplementation of Talaromyces cellulolyticus cellulase with KIF125 hemicellulase was more effective than that with the hemicellulases from other fungal sources in reducing the total enzyme loading for the improvement of xylose yield in the hydrolysis of ball-milling RS, due to its high β-xylosidase dominance. β-Xylosidase in KIF125 hemicellulase was purified and classified as a glycosyl hydrolase family 3 enzyme with relatively high specificity for xylobiose. The production of KIF125 β-xylosidase in the fermentor was estimated as 118 U/g-WDM-RS (2350 U/L culture) at 48 h. These results demonstrate that KIF125 is promising as a practical hemicellulase source to combine with on-site cellulase production using T. cellulolyticus.     

Involvement of SSAO-mediated deamination in adipose glucose transport and weight gain in obese diabetic KKAy mice

Semicarbazide-sensitive amine oxidase (SSAO) is located on outer surfaces of adipocytes and endothelial and vascular smooth muscle cells. This enzyme catalyzes deamination of methylamine and aminoacetone, leading to production of toxic formaldehyde and methylglyoxal, respectively, as well as hydrogen peroxide and ammonium. Several lines of evidence suggest that increased SSAO activity is related to chronic inflammation and vascular disorders related to diabetic complications. We found that a highly potent and selective SSAO inhibitor, (E)-2-(4-fluorophenethyl)-3-fluoroallylamine (FPFA), was capable of reducing numbers of atherosclerotic lesions as well as weight gain in obese KKAy mice fed an atherogenic diet. SSAO inhibitors cause a moderate and long-lasting hyperglycemia. Such an increase in serum glucose is a result of reduction of glucose uptake by adipocytes. SSAO-mediated deamination of endogenous methylamine substrates induces adipocyte glucose uptake and lipogenesis. Highly selective SSAO inhibitors can effectively block induced glucose uptake. The results suggest that increased SSAO-mediated deamination may be concomitantly related to obesity and vascular disorders associated with type 2 diabetes.     

Complete genome sequence of the bacterium Ketogulonicigenium vulgare Y25

Ketogulonicigenium vulgare is characterized by the efficient production of 2KGA from L-sorbose. Ketogulonicigenium vulgare Y25 is known as a 2-keto-L-gulonic acid-producing strain in the vitamin C industry. Here we report the finished, annotated genome sequence of Ketogulonicigenium vulgare Y25.     

Comparison of three ELISA kits for the differentiation of foot-and-mouth disease virus-infected from vaccinated animals

A study was performed to validate 3 FMDV 3ABC-I-ELISA kits developed in China for the differentiation of FMDV infected and vaccinated animals. Sets of sera from naive and vaccinated cattle as well as from cattle that had been infected were tested for antibodies against nonstructural proteins (NSPs) of FMDV by commercial diagnosis kits, Ceditest® FMDV-NS (Ceditest® kit), UBI® FMDV NONSTRUCTURAL PROTEIN ELISA DIRECTION INSERT (UBI® kit) and a FMDV 3ABC-I-ELISA kit developed at the Lanzhou Veterinary Research Institute. The test parameters (sensitivity and specificity) of the three kits were determined, and the result obtained from FMD 3ABC-I-ELISA kit was compared with that obtained from two foreign kits. The results indicated that the coincidence rate between the FMDV 3ABC-I-ELISA and Ceditest® kits was 98.05%, and the coincidence rate between the FMDV 3ABC-I-ELISA and UBI® kits was 94.4%; the sensitivity of both Ceditest® and FMDV 3ABC-I-ELISA kit was 100%. However, the sensitivity of the UBI® kit was only 81.8%. With sera from naive or vaccinated non-infected animals, the specificity of all tests exceeded 90%.     

棉铃虫Helicoverpa armigera的环境友好型诱杀技术研究

2003年和2004年,在山东惠民采用杀虫灯、性诱剂、杨树枝把等措施开展了诱杀棉铃虫Helicoverpa armigera成虫的防治试验.杀虫灯+10支性诱剂,杀虫灯+5支性诱剂+5支杨树枝把,杀虫灯+lO支杨树枝把,杀虫灯4种措施的日均诱蛾量分别为11.4、10.4、8.6和7.0头,性诱剂和杨树枝把均未显著提高对棉铃虫的诱杀效果.不同诱捕方案对棉铃虫累积诱蛾量随日期的变化符合Gompertz方程.普通灯和时控灯对棉铃虫的日均诱蛾量分别为19.9头和17.4头,二者差异不显著;时控灯对异色瓢虫和龟纹瓢虫的日均诱捕量均少于普通灯;减少开灯时间可在不显著降低棉铃虫诱杀量的同时,有效保护捕食性瓢虫.与普通灯相比,设置时间合理的时控灯(夜间19:00～23:00和3:00～5:00开灯)未显著降低棉铃虫的日均诱蛾量,而对异色瓢虫和龟纹瓢虫的日均诱捕量分别为2.0头和4.9头,均显著低于普通灯的3.7头和9.2头,合理设置开关灯控制模式可在不显著降低对棉铃虫诱杀效果的同时,降低近50%的天敌杀伤率,节约用电40%.     

一种宏观基因调控分子SATB1

自身多聚化的SATB1(special AT-rich sequences binding protein 1)围绕异染色质形成笼状结构分布在细胞核中,SATB1不仅结合染色质DNA的核基质结合区(matrix attachment regions,MARs),也结合核基质,能够使DNA锚定在核基质并形成袢环状结构(loop)。SATB1的磷酸化、乙酰化和小泛素化样修饰可调节其DNA结合能力和细胞核内亚结构的定位;SATB1与多种蛋白质相互作用,能够募集染色质重塑复合物和组蛋白修饰酶,实现对其靶基因表达的时空特异性调控。SATB1在调节细胞分化、细胞凋亡、肿瘤生长与转移和X染色体失活等方面起到重要作用,并有可能成为肿瘤转移的治疗靶点。