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Abstract: In situ transmission electron microscopy (TEM) observation of UO2 single crystal irradiated with Kr ions at high temperatures was conducted to understand the dislocation evolution due to high-energy radiation. The dislocation evolution in UO2 single crystal is shown to occur as nucleation and growth of dislocation loops at low-irradiation doses, followed by transformation to extended dislocation segments and networks at high doses, as well as shrinkage and annihilation of some loops and dislocations due to high temperature annealing. Generally the trends of dislocation evolution in UO2 were similar under Kr irradiation at different ion energies and temperatures (150keV at 600°C and 1MeV at 800°C) used in this work. Interstitial-type dislocation loops with Burgers vector along 〈110〉 were observed in the Kr-irradiated UO2. The irradiated specimens were denuded of dislocation loops near the surface. [Copyright &y& Elsevier]

Abstract: The microstructure, mechanical and thermal properties, as well as oxidation behavior, of in situ hot-pressed Zr2[Al(Si)]4C5–30vol.% SiC composite have been characterized. The microstructure is composed of elongated Zr2[Al(Si)]4C5 grains and embedded SiC particles. The composite shows superior hardness (Vickers hardness of 16.4GPa), stiffness (Young''s modulus of 386GPa), strength (bending strength of 353MPa), and toughness (fracture toughness of 6.62MPam1/2) compared to a monolithic Zr2[Al(Si)]4C5 ceramic. Stiffness is maintained up to 1600°C (323GPa) due to clean grain boundaries with no glassy phase. The composite also exhibits higher specific heat capacity and thermal conductivity as well as better oxidation resistance compared to Zr2[Al(Si)]4C5. [Copyright &y& Elsevier]

An abstract of the article "Completely Elimination of Xenograft SW620 Cancer by Combined Tumor Targeting MnSOD and Trail Genes," by Yan-hong Zhang, Jin-fa Gu, Li-li Zhao, Yi-gang Wang, Jin-hui Wang, Ling-feng He, Wei-guo Zou, Qi-Jun Qian, Cheng Qian and Xin-yuan Liu is presented.

An abstract of the article "Antitumor Effect of IL-24 Mediated by Tumor Targeting Vector ZD55 Is Much Better Than That Mediated by Replication Deficient Adenovirus," by Li-li Zhao and colleagues is presented.

In eukaryotes, histone acetylation and deacetylation play an important role in the regulation of gene expression. Histone acetylation levels are reversibly regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs). Increasing evidence highlights histone acetylation plays essential roles in the regulation of gene expression in plant response to environmental stress. In this review, we discussed the recent advance of histone acetylation in the regulation of abiotic stress responses including temperature, light, salt and drought stress. This information will contribute to our understanding of how plants adapt to environmental changes. As the mechanisms of epigenetic regulation are conserved in many plants, research in this field has potential applications in improvement of agricultural productivity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Li, Liu, He, Li, Guo, Zhang, Zhao and Guo.)

Background: Human interferon-beta (IFN-beta) has been widely used in gene therapy for its antitumor activity but its therapeutic effect is limited. The conditionally replicative adenovirus ONYX-015 (a E1B-55-kDa-deleted adenovirus) targets well to tumor cells, but is not potent enough to cause significant tumor regression. To solve these problems, a tumor-selective replicating adenovirus expressing IFN-beta was constructed in this study., Methods: The oncolytic adenoviruses were generated by homologous recombination in packaging cells. The expression of the IFN-beta protein was detected by enzyme-linked immunosorbent assay (ELISA). The antitumor efficacy of ZD55-IFN-beta was evaluated in cell lines and human hepatocellular carcinoma xenografts in nude mice., Results: ZD55-IFN-beta can express much more IFN-beta than Ad-IFN-beta because of the replication of the ZD55 vector. Our data showed that ZD55-IFN-beta could exert a strong cytopathic effect on tumor cells (about 100-fold higher than Ad-IFN-beta or ONYX-015). Moreover, no obvious cytotoxic or apoptotic effects were detected in normal cells infected with ZD55-IFN-beta., Conclusions: The antitumor efficacy of IFN-beta could be significantly improved due to the increased gene expression level from the tumor-selective replicating vector. The oncolytic adenovirus expressing IFN-beta may provide a novel approach for cancer gene therapy., ((c) 2008 John Wiley & Sons, Ltd.)

Background & Objective: Neoadjuvant chemotherapy has gained increasing attention as a treatment for gastric cancer since Wilke first reported its application to the treatment of gastric cancer in 1989. However, its value in treating gastric cancer remains controversial. This research was to assess the efficacy of neoadjuvant chemotherapy on gastric cancer through a Meta analysis of the randomized controlled trials published worldwide in both English and Chinese., Methods: Cochrane systematic evaluation was used to search through Cochrane libraries of clinical comparative trials, PubMed, Embase, Chinese Biomedical Literature Database (CBM), Chinese Scientific Journal Full-text Database (CSJD) and Chinese Journal Full-text Database (CJFD), aided with manual retrieval and other retrievals. The quality of the assessment was independently evaluated and cross-checked by two evaluators, and the results of homogeneous studies were analyzed with RevMan4.2.10 software., Results: Five randomized controlled trials involved a total of 838 patients were studied. Of the 5 trials, 2 were performed in Japan, 1 in the Netherlands, 1 in the United Kingdom, 1 in China. Of the 838 patients, 373 were treated with neoadjuvant chemotherapy and 465 were treated with surgery alone. Among the above 5 studies, one used blind method and one described random allocation concealment method. No statistical differences were found in the resection rate, cure rate, 1-and 5-year survival rates between neoadjuvant chemotherapy group and surgery group [odds ratio (OR)=1.09, 95% confidence interval (CI)=0.67-1.77 for resection rate; OR=1.25, 95% CI=0.85-1.84 for cure rate; OR=1.61, 95% CI=0.90-2.90 for 1-year survival rate; OR=1.13, 95% CI=0.83-1.53 for 5-year survival rate]., Conclusions: The efficacy of neoadjuvant chemotherapy on gastric cancer is not better than that of surgery alone. Therefore, neoadjuvant chemotherapy should not be recommended as a regular treatment for gastric cancer before obtaining evidences of its certain efficacy on gastric cancer.

Background: Bladder cancer is a relatively common tumor in the urinary system, in which mitomycin C (MMC)-based chemotherapy or combination chemotherapy has been mainly used to treat patients with advanced bladder cancer. The prognosis of patients with advanced bladder cancer is still extremely poor in spite of recent therapeutic advances. To improve the prognosis, the sensitivity of tumor cells to mitomycin C by the induction of apoptosis with the abating heat shock protein 70 (HSP70) expression in human bladder cancer cell lines of BIU-87 was investigated., Methods: HSP70 expression was abated in BIU-87 cells by HSP mRNA antisense oligomers. MTT assay and the clone-forming test were used for evaluating the sensitivity of cells to MMC. Apoptosis was assessed using both fluorescent microscopy after staining the cells with Hoechst 33258 and DNA fragment ladder agarose electrophoresis. Thirty-two male six-week-old BALB/c nude mice, at the beginning of the experiment, were used to evaluate the effect of antisense oligomers (ASO) on the tumor formation in vivo., Results: HSP70 expression in BIU-87 was effectively abated by HSP70 mRNA antisense oligomers. The percentage of apoptotic cells in ASO group was greater than in sense oligomers (SO) [P < 0.05, (18.31 +/- 2.89)% vs (1.89 +/- 0.74)%], nonsense oligomers (NO) [P < 0.05, (18.31 +/- 2.89)% vs (1.78 +/- 0.92)%] and blank groups [P < 0.05, (18.31 +/- 2.89)% vs (1.87 +/- 0.84)%], while the sensitivity of tumor cells to mitomycin C was enhanced. The in vivo tumor inhibition rate of ASO plus MMC (> 50%) was more than that of ASO or MMC group alone (all P < 0.05)., Conclusions: The abating level of HSP70 expression can strengthen the sensitivity of BIU-87 to MMC. One of this effect might be related to the induction of apoptosis by abating HSP70 expression.

Objective: To investigate whether the heat shock protein (HSP) 70 antisense oligomers can enhance the sensitivity of bladder cancer cell EJ to mitomycin C., Methods: The HSP70 mRNA of EJ cells was blocked by the 10 micromol/L HSP70 antisense oligomers, while its effect on cell growth was evaluated by methyl thiazolyl tetrazolium (MTT) and colony forming ability test., Results: The HSP70 expressions in HSP70 antisense treated group were lower than the corresponding sense and nonsense treated groups (P < 0.01). While, the increased sensitivity of EJ to mitomycin C was found in antisense treated group, compared with the corresponding sense and nonsense treated groups (P < 0.01)., Conclusion: The sensitivity of bladder cancer cell EJ to mitomycin C was enhanced by the blockage of the HSP70 expression.

Objective: To investigate the expression of cyclooxygenase-2 (COX-2) in bladder transitional cell carcinoma tissues, and understand its clinical significance., Methods: Reversal transcription polymerase chain reaction (RT-PCR) was used to assess the expression of COX-2 mRNA in 52 cases of bladder transitional cell carcinoma tissues and 17 cases of normal bladder tissues far from neoplasm; Western blot was used to assess the expression of COX-2 protein in 49 cases of bladder cancerous tissues and 17 cases of normal tissues., Results: Positive expression of COX-2 mRNA was detected in 83% (43/52) of bladder cancer tissues and in 29% (5/17) of normal tissues by RT-PCR and there was significant difference in expression of COX-2 mRNA between cancer tissues and normal tissues. Western blot analysis showed that expression of COX-2 protein was correlation with the stage and grade of cancer., Conclusion: COX-2 is overexpressed in bladder transitional cell carcinoma. COX-2 maybe play a certain role in carcinogenesis and progression of bladder cancer and turn into a useful target of chemoprevention of bladder cancer.