Space Radiation-Induced Hematopoietic Stem Cell Injury

Space radiation is an unavoidable health risk during space activities. Hematopoietic cells are sensitive to radiation including proton and oxygen radiation and so on. Understanding the mechanisms responsible for detrimental effects of space radiation is important to achieve countermeasures protecting hematopoietic stem cells (HSCs), which generates different hematopoietic populations. However, the biological effects of various sources of space radiation on HSCs are not understood well. Induction of cellular apoptosis, reactive oxygen species (ROS), and DNA damage upon space radiation is believed to be critical mediators for HSC damage. In this chapter, we will mainly discuss the biological effectiveness of proton and oxygen radiation on the numbers and function of HSCs. Space radiation-induced apoptosis, ROS, and DNA damage were examined as well, which will provide foundation to develop novel strategies protecting HSCs from space radiation

Bifacial dye-sensitized solar cells : a strategy to enhance overall efficiency based on transparent polyaniline electrode

Dye-sensitized solar cell (DSSC) is a promising solution to global energy and environmental problems because of its clean, low-cost, high efficiency, good durability, and easy fabrication. However, enhancing the efficiency of the DSSC still is an important issue. Here we devise a bifacial DSSC based on a transparent polyaniline (PANI) counter electrode (CE). Owing to the sunlight irradiation simultaneously from the front and the rear sides, more dye molecules are excited and more carriers are generated, which results in the enhancement of short-circuit current density and therefore overall conversion efficiency. The photoelectric properties of PANI can be improved by modifying with 4-aminothiophenol (4-ATP). The bifacial DSSC with 4-ATP/PANI CE achieves a light-to-electric energy conversion efficiency of 8.35%, which is increased by ,24.6% compared to the DSSC irradiated from the front only. This new concept along with promising results provides a new approach for enhancing the photovoltaic performances of solar cells.The authors acknowledge the financial joint support by the National High Technology Research and Development Program of China (No. 2009AA03Z217), the National Natural Science Foundation of China (nos. 90922028, U1205112, 51002053, 61306077), Seed Fund from Ocean University of China, and Fundamental Research Funds for the Central Universities (201313001)

Thermochromic properties of vanadium oxide films prepared by dc reactive magnetron sputtering

A transparent vanadium oxide film has been one of the most studied electrochromic (EC) and Thermochromic (TC) materials. Vanadium oxide films were deposited at different substrate temperatures up to 400 °Cand different ratios of the oxygen partial pressure (PO2). SEM,AFMand X-ray diffraction's results show detail structure data of the films. IR mode assignments of the films measured by IR reflection–absorbance in NGIA (near grazing incidence angle) are given. It is found that the film has V2O5 and VO2 combined structures. The films exhibit clear changes in transmittance when the environment temperature (Te) is varied, especially in the 3600–4000 cm−1 range. Applying a Te that is higher than a critical temperature (Tc) to the samples, the as-RT (room temperature) deposited film with 9% PO2 has a transmittance variation of 30%, but the films that were deposited on a heated substrate of 400 °C have little variation. There is tendency of bigger variation in transmittance for the sample deposited at a larger PO2, when it is applied by 200 °C Te

The impact of Metastasis Suppressor-1, MTSS1, on oesophageal squamous cell carcinoma and its clinical significance

<p>Abstract</p> <p>Background</p> <p>Metastasis suppressor-1 (MTSS1) has been proposed to function as a cytoskeletal protein with a role in cancer metastasis. Recent studies have demonstrated the clinical significance of MTSS1 in certain type of cancers, yet the clinical relevance of MTSS1 in oesophageal squamous cell carcinoma (ESCC) has not been reported.</p> <p>Methods</p> <p>In this study, we assessed the expression levels of MTSS1 in tumours and its matched adjacent non-tumour tissues obtained from 105 ESCC patients. We also used ESCC cells with differing MTSS1 expression and assessed the influence of MTSS1 on ESCC cells.</p> <p>Results</p> <p>Down-regulation of MTSS1 expression was observed both in oesophageal tumour tissues and ESCC cancer cell lines. We also reported that MTSS1 expression was associated with tumour grade (p = 0.024), lymph node metastasis (p = 0.010) and overall survival (p = 0.035). Patients with high levels of MTSS1 transcripts had a favorable prognosis in comparison with those who had reduced or absent expression levels. Using over-expression and knockdown approach, we created sublines from ESCC cells and further demonstrated that MTSS1 expression in ESCC cells significantly influenced the aggressiveness of the oesophageal cancer cells, by reducing their cellular migration and in vitro invasiveness.</p> <p>Conclusion</p> <p>MTSS1 serves as a potential prognostic indicator in human ESCC and may be an important target for cancer therapy.</p

Molecular impact of bone morphogenetic protein 7, on lung cancer cells and its clinical significance

The aim of this study was to investigate the expression of bone morphogenetic protein 7 (BMP7), in human pulmonary cancer tissues/cells and to evaluate the cellular impact of bone morphogenetic proteins on pulmonary cancer cells. BMP7 expression was determined in human lung cancer cell lines. The invasiveness and growth of cells transfected with BMP7, in vitro, were evaluated using the in vitro invasion assay and in vitro tumour models. Cellular migration was analysed using wounding assays. BMP7-positive tumours correlated with the absence of bone metastasis (P=0.040). In this analysis, we identified that 4 of 4 small cell lung cancer (SCLC) tissue specimens had no BMP7 expression, which illustrated that BMP7 may have no role in SCLC. BMP7 expression was not correlated with the overall survival time in lung cancer patients. Downregulation of BMP7 expression significantly inhibited the invasiveness of SPC-A1 cells (P0.5 respectively). In conclusion, we have demonstrated that BMP7 has an important role in controlling lung cancer cell motility and invasiveness, without affecting the growth process, cell proliferation and cell apoptosis. A higher BMP7 expression may be an indicator for bone metastasis. The therapeutic role of BMP7 warrants further investigation

Transient Inhibition of mTORC1 Signaling Ameliorates Irradiation-Induced Liver Damage

Recurrent liver cancer after surgery is often treated with radiotherapy, which induces liver damage. It has been documented that activation of the TGF-β and NF-κB signaling pathways plays important roles in irradiation-induced liver pathologies. However, the significance of mTOR signaling remains undefined after irradiation exposure. In the present study, we investigated the effects of inhibiting mTORC1 signaling on irradiated livers. Male C57BL/6J mice were acutely exposed to 8.0 Gy of X-ray total body irradiation and subsequently treated with rapamycin. The effects of rapamycin treatment on irradiated livers were examined at days 1, 3, and 7 after exposure. The results showed that 8.0 Gy of irradiation resulted in hepatocyte edema, hemorrhage, and sinusoidal congestion along with a decrease of ALB expression. Exposure of mice to irradiation significantly activated the mTORC1 signaling pathway determined by pS6 and p-mTOR expression via western blot and immunostaining. Transient inhibition of mTORC1 signaling by rapamycin treatment consistently accelerated liver recovery from irradiation, which was evidenced by decreasing sinusoidal congestion and increasing ALB expression after irradiation. The protective role of rapamycin on irradiated livers might be mediated by decreasing cellular apoptosis and increasing autophagy. These data suggest that transient inhibition of mTORC1 signaling by rapamycin protects livers against irradiation-induced damage

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Expression of bone morphogenetic protein 7 in lung cancer and its biological impact on lung cancer cells

Background: Lung cancer is the leading cause of cancer-related death in the world, with metastasis being the main reason for the mortality. As a member of the bone morphogenetic protein (BMP) family, BMP7 has important biological functions in malignant tumours. As yet, however, there is little knowledge of the role of BMP7 and its cellular function in lung cancer. This study aimed to investigate the biological impact of BMP7 on lung cancer cells and the expression pattern of the molecule in clinical lung carcinomas. Materials and Methods: The expression pattern of BMP7 and its receptors was examined in different lung cancer cell lines and normal cells. The biological function of BMP7 in lung cancer cells was further evaluated. The impact of BMP7 on the downstream signalling, namely the activation of SMAD1 status, was assessed. BMP7 expression level was assessed in a cohort of human lung cancer samples (tumour, n=70; matched normal tissues, n=70), in association with patient clinical variables, using quantitative analysis of BMP7. Results: In vitro, it was found that recombinant human (rh)BMP7 significantly reduced cellular motility of lung cancer cell line, SK-MES1, and its adhesion to Matrigel (p<0.05). rhBMP7 was also able to significantly reduce invasion of lung cancer cells (p<0.05). We found that rhBMP7 had little effect on actual growth of the lung cells. In addition, BMP7 was able to regulate the phosphorylation of SMAD1, a downstream signalling intermediate of the BMP7 signalling pathway. The study further revealed that reduced levels of BMP7 in lung cancer tissues significantly correlated with lymph node metastasis for lung cancer patients (p<0.05). Conclusion: BMP7 protein is a pivotal regulator of cell motility in lung cancer with little impact on the growth of tumour cells. BMP7 expression is linked to lymph node involvement in patients with lung cancer. These results indicate that BMP7 plays a key role in regulating the progression of lung cancer

Mediastinal lymphadenectomy fulfilling NCCN criteria may improve the outcome of clinical N0-1 and pathological N2 non-small cell lung cancer

Background: This retrospective study investigated whether mediastinal lymphadenectomy compliant with the National Comprehensive Cancer Network (NCCN) criteria will improve the oncological outcomes of clinical early-stage lung cancer. Methods: From 2003–2010, 712 consecutive cases of clinical N0/1 were included for retrospective analysis, including 152 confirmed cases of pN2 and 560 of pN0–1 disease following surgery. Group A was defined as the cases fulfilling NCCN lymphadenectomy criteria (≥ three stations of N2 nodes dissection) and group B included all other cases. The groups were stratified according to pN status and the outcomes were assessed. Results: Five-year overall survival (OS) and 5-year disease-free survival (DFS) were significantly different between group A versus B [72%±2% vs. 63%±4% (OS), P=0.014; 58.0%±2% vs. 49%±4% (DFS), P=0.038] in the whole cohort. After stratification by pN status, this difference was remained in pN2 subgroup [50%±5% vs. 25%±9% (OS), P=0.006; 31.0%±4% vs. 13%±7% (DFS), P=0.014], but not in pN0–1 subgroups. Cox regression analysis showed that performing a lymphadenectomy fulfilling NCCN criteria was a significant prognostic factor for OS either in the whole cohort [P=0.003, hazard ratio (HR): 0.598, 95% confidence interval (CI): 0.425–0.841] or in patients of pN2 status (P=0.038, HR: 0.559, 95% CI: 0.323–0.968). Cases with ≥4 N2 stations dissected did not achieve better survival benefit compared to those harvesting 3 stations in cN0/1–pN2 group (P=0.152). Conclusions: Mediastinal lymphadenectomy fulfilling NCCN criteria appears to improve the survival of unexpected N2 group (cN0/1-pN2) among early-stage lung cancer patients. More extended N2 node dissection may not further improve the outcome in this group.8 page(s