Superoxide dismutases enhance H2O2-induced DNA damage and alter its site specificity

AbstractSuperoxide dismutases (SODs) are involved in the protection of cells from oxygen toxicity. However, several papers have reported that the overexpression of CuZn-SOD causes oxidative damage to cells. We investigated a mechanism by which an excess of SODs accelerates oxidative stress. The presence of CuZn-SOD, Mn-SOD or Mn(II) enhanced the frequency of DNA damage induced by hydrogen peroxide (H2O2) and Cu(II), and altered the site specificity of the latter: H2O2 induced Cu(II)-dependent DNA damage with high frequency at the 5′-guanine of poly G sequences; when SODs were added, the frequency of cleavages at thymine and cytosine residues increased. SODs also enhanced the formation of 8-oxo-7,8-dihydro-2′-deoxyguanosine by H2O2 and Cu(II). We conclude that SODs may increase carcinogenic risks, e.g. of tumors in Down syndrome

Water utilization situations at two suburban areas in Lao P.D,R. - The cases of Lahanam district, Savannakhet and its changing pattern in Xaithani district in Vienntiane Capital -

Utilization and availability of water source is a serious health problem in developing countries. To analyze local condition of water utilization patterns in Lao PDR, a comparative study on water utility and sanitation condition along the local context was conducted at 2 villages in Savannakhet province and a village in Vientiane Capital in 2005. There was no city water supply in the two areas. Water utilization and the sanitation data of the Capital village in 2000 were also employed to compare change of the situation for 6 years at the place. In Savannakhet, main water sources were dug well, river, purchase-bottle water, and rainwater storage. Rainwater was common drinking source, and a half of them drink before boiling. In the capital area, main water sources were well (borehole and dug wells), purchase-bottle water both in 2000 and in 2005. Utilization of drinking water, well water was chosen firstly and the water boiling practice rates were not so different in both areas. The consumption of purchase water was higher in Vientiane than in Savannakhet. Also, it was demonstrated that the rate of purchase water increased much at the capital in these six years

Multiphoton Processes and Attosecond Physics

Recent advances in ultrashort pulsed laser technology have opened new frontiers in atomic, molecular and optical sciences. The 12th International Conference on Multiphoton Processes (ICOMP12) and the 3rd International Conference on Attosecond Physics (ATTO3), held jointly in Sapporo, Japan, during July 3-8, showcased studies at the forefront of research on multiphoton processes and attosecond physics. This book summarizes presentations and discussions from these two conferences

Water, Livelihood and Health in Attapeu Province in Lao PDR

This paper presents the results of an investigation on water-borne infectious diseaseconducted among the people of Attapeu province from 2003 to 2008. Regardless of the lastcholera epidemic in Attapeu province, Lao PDR in the year 1999, the local peoples'awareness of cholera was remarkably low, as demonstrated by the knowledge survey ondiarrheal diseases performed in the province in 2006. In the case study material, derivedfrom continuous field observations on malaria among permanent residents in relocatedvillages in Sanxay district from 2004 to 2008, the infection rate among febrile cases was ashigh as 45% in the early resettlement period, while it was proved that the rate fell later to1.9-14%. Judging from the environmental condition of this settlement area, this papermakes clear the persistent threat of malaria. Furthermore, among the villagers, hookworminfection was highly prevalent. However, liver fluke infections were scarce and noascariasis was found from parasitic stool examination in 2007. Water quality analysis ofthe water sources resulted in remarkably safe water from tube wells from 2003 to 2008

食餌性因子でエピゲノム異常のリセットは可能か？―食によるがん予防を目指して―

application/pdf感染・炎症などの環境因子がゲノム・エピゲノム異常を誘発する。一方で、食餌性因子が有効に作用し、異常の制御に働くとの報告もある。食餌性因子の影響評価に先立ち、我々はメチル化DNAの定量法を検討し、バイサルファイト処理DNAを用い、Bisulfite Amplicon Sequencing (BAS)法によりメチル化率を高精度に測定できることを明らかにした。Epstein-Barrウイルス感染関連上咽頭癌の流行地に、発病率が低い地域があり飲茶習慣との関係が注目される。そこで茶葉ポリフェノールエピガロカテキンガレートでヒト上咽頭癌培養細胞を処理し、DNAメチル率と遺伝子発現変化について検討している。Environmental factors including infection and inflammation induce the alteration of genome and epigenome, which may lead to carcinogenesis. Several reports suggest that dietary factors may change the status. First, we examined methods for quantification of DNA methylation, and we could get DNA methylation rates of candidate genes by Bisulfite Amplicon Sequencing (BAS) with high accuracy. In the endemic area of Epstein-Barr virus-associated nasopharyngeal carcinoma, there is an area having low incidence, and their custom of drinking tea attract attention. So, we are checking the effects of tea polyphenol, epigallocatechin gallate (EGCG) on DNA methylation rates and gene expression levels in human nasopharyngeal carcinoma cell lines.2015年度～2016年度科学研究費補助金(挑戦的萌芽研究)研究成果報告書15K1523