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51.
Nayu Ikeda Manami Inoue Hiroyasu Iso Shunya Ikeda Toshihiko Satoh Mitsuhiko Noda Tetsuya Mizoue Hironori Imano Eiko Saito Kota Katanoda Tomotaka Sobue Shoichiro Tsugane Mohsen Naghavi Majid Ezzati Kenji Shibuya 《PLoS medicine》2012,9(1)
Background
The population of Japan has achieved the longest life expectancy in the world. To further improve population health, consistent and comparative evidence on mortality attributable to preventable risk factors is necessary for setting priorities for health policies and programs. Although several past studies have quantified the impact of individual risk factors in Japan, to our knowledge no study has assessed and compared the effects of multiple modifiable risk factors for non-communicable diseases and injuries using a standard framework. We estimated the effects of 16 risk factors on cause-specific deaths and life expectancy in Japan.Methods and Findings
We obtained data on risk factor exposures from the National Health and Nutrition Survey and epidemiological studies, data on the number of cause-specific deaths from vital records adjusted for ill-defined codes, and data on relative risks from epidemiological studies and meta-analyses. We applied a comparative risk assessment framework to estimate effects of excess risks on deaths and life expectancy at age 40 y. In 2007, tobacco smoking and high blood pressure accounted for 129,000 deaths (95% CI: 115,000–154,000) and 104,000 deaths (95% CI: 86,000–119,000), respectively, followed by physical inactivity (52,000 deaths, 95% CI: 47,000–58,000), high blood glucose (34,000 deaths, 95% CI: 26,000–43,000), high dietary salt intake (34,000 deaths, 95% CI: 27,000–39,000), and alcohol use (31,000 deaths, 95% CI: 28,000–35,000). In recent decades, cancer mortality attributable to tobacco smoking has increased in the elderly, while stroke mortality attributable to high blood pressure has declined. Life expectancy at age 40 y in 2007 would have been extended by 1.4 y for both sexes (men, 95% CI: 1.3–1.6; women, 95% CI: 1.2–1.7) if exposures to multiple cardiovascular risk factors had been reduced to their optimal levels as determined by a theoretical-minimum-risk exposure distribution.Conclusions
Tobacco smoking and high blood pressure are the two major risk factors for adult mortality from non-communicable diseases and injuries in Japan. There is a large potential population health gain if multiple risk factors are jointly controlled. Please see later in the article for the Editors'' Summary 相似文献52.
Akifumi Ohtaka 《Limnology》2018,19(3):367-373
In surveys conducted during 2000–2005, 39 taxa of aquatic oligochaetes belonging to the families Enchytraeidae and Naididae were found in Lake Tonle Sap in the Mekong River Basin, Cambodia. Dominated by naidines and pristinines (29 taxa), they mainly comprised widely distributed species as well as South Asian and Southeast Asian species. Among the four areas studied, the littoral regions of the lake—where inundated forests and aquatic vegetation developed during the flooded seasons—presented the highest number of species. Submerged vegetation in the littoral Lake Tonle Sap harbored abundant epiphytic oligochaetes, especially Stylaria fossularis. In contrast to the rich abundance of naidine and pristinine fauna, tubificines and ryhacodrilines were scarce in and around the lake, irrespective of the vegetation in their habitats. Several Aulodrilus species and Branchiura sowerbyi were the main representatives of the benthic oligochaete assemblages throughout the offshore zone of the lake without vegetation. It is noteworthy that the widely distributed tubificines Tubifex tubifex and Limnodrilus hoffmeisteri were not found in any surveyed locality. 相似文献
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Shiki Takamura Eiji Kajiwara Sachiyo Tsuji-Kawahara Tomoko Masumoto Makoto Fujisawa Maiko Kato Tomomi Chikaishi Yuri Kawasaki Saori Kinoshita Manami Itoi Nobuo Sakaguchi Masaaki Miyazawa 《PLoS pathogens》2014,10(3)
In chronic viral infections, persistent antigen presentation causes progressive exhaustion of virus-specific CD8+ T cells. It has become clear, however, that virus-specific naïve CD8+ T cells newly generated from the thymus can be primed with persisting antigens. In the setting of low antigen density and resolved inflammation, newly primed CD8+ T cells are preferentially recruited into the functional memory pool. Thus, continual recruitment of naïve CD8+ T cells from the thymus is important for preserving the population of functional memory CD8+ T cells in chronically infected animals. Friend virus (FV) is the pathogenic murine retrovirus that establishes chronic infection in adult mice, which is bolstered by the profound exhaustion of virus-specific CD8+ T cells induced during the early phase of infection. Here we show an additional evasion strategy in which FV disseminates efficiently into the thymus, ultimately leading to clonal deletion of thymocytes that are reactive to FV antigens. Owing to the resultant lack of virus-specific recent thymic emigrants, along with the above exhaustion of antigen-experienced peripheral CD8+ T cells, mice chronically infected with FV fail to establish a functional virus-specific CD8+ T cell pool, and are highly susceptible to challenge with tumor cells expressing FV-encoded antigen. However, FV-specific naïve CD8+ T cells generated in uninfected mice can be primed and differentiate into functional memory CD8+ T cells upon their transfer into chronically infected animals. These findings indicate that virus-induced central tolerance that develops during the chronic phase of infection accelerates the accumulation of dysfunctional memory CD8+ T cells. 相似文献
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Divalent ion sensitivity of hammerhead ribozymes is significantly reduced when the RNA structure includes appropriate tertiary stabilization. Therefore, we investigated the activity of the tertiary stabilized "RzB" hammerhead ribozyme in several nondivalent ions. Ribozyme RzB is active in spermidine and Na(+) alone, although the cleavage rates are reduced by more than 1,000-fold relative to the rates observed in Mg(2+) and in transition metal ions. The trivalent cobalt hexammine (CoHex) ion is often used as an exchange-inert analog of hydrated magnesium ion. Trans-cleavage rates exceeded 8 min(-1) in 20 mM CoHex, which promoted cleavage through outersphere interactions. The stimulation of catalysis afforded by the tertiary structural interactions within RzB does not require Mg(2+), unlike other extended hammerhead ribozymes. Site-specific interaction with at least one Mg(2+) ion is suggested by CoHex competition experiments. In the presence of a constant, low concentration of Mg(2+), low concentrations of CoHex decreased the rate by two to three orders of magnitude relative to the rate in Mg(2+) alone. Cleavage rates increased as CoHex concentrations were raised further, but the final fraction cleaved was lower than what was observed in CoHex or Mg(2+) alone. These observations suggest that Mg(2+) and CoHex compete for binding and that they cause misfolded structures when they are together. The results of this study support the existence of an alternate catalytic mechanism used by nondivalent ions (especially CoHex) that is distinct from the one promoted by divalent metal ions, and they imply that divalent metals influence catalysis through a specific nonstructural role. 相似文献
59.
Manami Koshiguchi Hitoshi Komazaki Shizuka Hirai 《Bioscience, biotechnology, and biochemistry》2017,81(5):966-971
Ferulic acid (FA) is a phenol compound found in plants that has anti-inflammatory properties. Indoleamine 2, 3-dioxygenase (IDO) is a tryptophan catabolic enzyme induced in immune cells, including glial cells, during inflammation. Enhanced IDO expression leads to reduced tryptophan levels and increased levels of toxic metabolites, including quinolinic acid. Therefore, inhibition of IDO expression may be effective in suppressing progression of neurodegenerative diseases. In this study, we examined the effect of FA in microglial cells on IDO expression levels and related inflammatory signal molecules. FA suppressed LPS-induced IDO mRNA expression and also suppressed nuclear translocation of NF-κB and phosphorylation of p38 MAPK. However, FA did not affect the production of LPS-induced inflammatory mediators and phosphorylation of JNK. Our results indicate that FA suppresses LPS-induced IDO mRNA expression, which may be mediated by inhibition of the NF-κB and p38 MAPK pathways in microglial cells. 相似文献
60.
Shiratsuchi A Ichiki M Okamoto Y Ueda N Sugimoto N Takuwa Y Nakanishi Y 《Journal of biochemistry》2009,145(1):43-50
The production of N-acylethanolamine (NAE) is enhanced during inflammation. NAE is synthesized from phosphatidylethanolamine with N-acylphosphatidylethanolamine (NAPE) as a precursor. The amount of NAPE at the site of inflammation exceeds that of NAE. This evokes the possibility that NAPE possesses a biological function, as does NAE. We here examined if N-palmitoylphosphatidylethanolamine (NPPE), a precursor of N-palmitoylethanolamine, modulates the state of inflammation. We found that the level of the phagocytosis of latex beads, Staphylococcus aureus, Escherichia coli, or apoptotic cells by mouse peritoneal macrophages or J774A.1 macrophages was reduced in the presence of liposomes containing NPPE, while that of dextran remained unaffected. This action of NPPE seemed to be due to the inhibition of the activation of Rac1 and Cdc42 in macrophages. These results suggested that NAPE is bioactive lipid acting toward the termination of inflammation. 相似文献