[The protective effects of SB203580 against mortality and radiation induced intestinal injury of mice].

This study is to investigate the protective effects of the SB203580 against radiation induced mortality and intestinal injury of mice. A total of 67 male C57BL/6 mice (20.0-22.0 g) were matched according to body weight and randomly assigned to one of three groups: control, total body irradiation exposure (IR, 7.2 Gy) only, and IR (7.2 Gy) + SB203580 (15 mg x kg(-1)). 30 days survival rate was observed in the experiment. In intestinal injury experiment, the expression levels of caspase-3, Ki67, p53 and p-p38 were assayed in the mice intestine crypts. The results showed that the 30 days survival rate was 100% (control), 0 (IR) and 40% (IR+ SB203580), separately. Compared to the IR groups, the positive cells of caspase-3, p53 and p-p38 in crypt cells decreased 33.00%, 21.78% and 34.63%, respectively. The rate of positive cells of Ki67 increased 37.96%. Significant difference was found between all of them (P < 0.01). SB203580 potently protected against radiation-induced lethal and intestinal injury in mice, and it may be a potential radio protector.

Retinoblastoma 94 enhances radiation treatment of esophageal squamous cell carcinoma in vitro and in vivo.

We performed the study to investigate whether adenovirus-mediated retinoblastoma 94 (RB94) gene transfer could enhance radiation treatment of esophageal squamous cell carcinoma (ESCC) in vitro and in vivo. ESCC cells (Kyse150 cell line) were cultivated in vitro and tumors originated from the cell line were propagated as xenografts in nude mice. Treatment with Ad-RB94 and/or ionizing radiation (IR) was carried out both in vitro and in vivo with Ad-LacZ control vector and blank control. Cell viability, cell cycle distribution, cell apoptosis, tumor growth and transfected gene expression were evaluated and tumor degeneration was analyzed. The data of quantification real-time PCR assays and immunohistochemistry staining using RB antibody indicated that RB94 was efficiently transfected into Kyse150 cells. In vitro, data of cell growth assay indicated that treatment with Ad-RB94 improved radiation treatment of Kyse150 cells. Tumor xenograft studies, pathological analysis of H.E. staining and Ki67 staining suggested transfecting RB94 enhanced tumor regression induced by radiation treatment in vivo. In addition, data of Annexin V, TUNEL and cell cycle distribution assays proposed combination treatment effectively induced cell apoptosis and cell cycle arresting in G2/M phase. In conclusion, transferring RB94 gene by the adenoviral vector enhances radiation treatment of ESCC.

Toxicologic effects of gold nanoparticles in vivo by different administration routes.

Gold nanoparticles have potential applications in biomedicine, but one of the important concerns is about their safety. Most toxicology data are derived from in vitro studies and may not reflect in vivo responses. Here, an animal toxicity study of 13.5 nm gold nanoparticles in mice is presented. Animal survival, weight, hematology, morphology, and organ index are characterized at different concentrations (137.5-2200 µg/kg) over 14-28 days. The results show that low concentrations of gold nanoparticles do not cause an obvious decrease in body weight or appreciable toxicity, even after their breakdown in vivo. High concentrations of gold nanoparticles induced decreases in body weight, red blood cells, and hematocrit. It was also found that gold nanoparticles administered orally caused significant decreases in body weight, spleen index, and red blood cells. Of the three administration routes, the oral and intraperitoneal routes showed the highest toxicity, and the tail vein injection showed the lowest toxicity. Combining the results of all of these studies, we suggest that targeted gold nanopartices by tail vein injection may be suitable for enhancement of radiotherapy, photothermal therapy, and related medical diagnostic procedures.