NASDA's new test facilities for satellites and rockets

The National Space Development Agency of Japan (NASDA) has decided to construct integrated environmental and structural test facilities for large space satellites. These facilities are under construction. The new test facilities are described and some technical considerations, especially for the unique vibration test facility are discussed

Mechanical and fatigue properties of long carbon fiber reinforced plastics at low temperature

The mechanical properties of long unidirectional (UD) and crossply (CR) carbon fiber reinforced plastics (CFRPs) were investigated at a low temperature (−196 °C). The CFRPs were fabricated from 60 vol.% carbon fiber and epoxy resin. The bending strength of the UD-CFRP was approximately twice that of the CR-CFRP. The high strength of the UD-CFRP was directly attributed to the amount of carbon fiber oriented along the loading direction: 60% for UD-CFRP compared with 30% for CR-CFRP. The low-temperature (−196 °C) tensile and fatigue strengths of the UD-CFRP were over 1.5 times greater than those at room temperature (20 °C). This was attributed to the increased epoxy strength at low temperatures along with the internal compressive stress arising from the different thermal expansion coefficients of the carbon fiber and epoxy. Both the epoxy strength and internal compressive strength were employed as factors in a compound law to numerically estimate the low-temperature tensile strength. This work presents a systematic analysis for changes in the CFRP material properties at low temperatures

Increased Life Span due to Calorie Restriction in Respiratory-Deficient Yeast

A model for replicative life span extension by calorie restriction (CR) in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD(+)–dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD(+) or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1) demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2) show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3) suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742

Deletion of H-ferritin in macrophages alleviates obesity and diabetes induced by high-fat diet in mice

Aims/hypothesis Iron accumulation affects obesity and diabetes, both of which are ameliorated by iron reduction. Ferritin, an iron storage protein, plays a crucial role in iron metabolism. H-ferritin exerts its cytoprotective action by reducing toxicity via its ferroxidase activity. We investigated the role of macrophage H-ferritin in obesity and diabetes. Methods Conditional macrophage-specific H-ferritin knockout (LysM-Cre FthKO) mice were used and divided into 4 groups; Wild-type (WT) and LysM-Cre FthKO mice with normal diet (ND), and WT and LysM-Cre Fth-KO mice with high-fat diet (HFD). Results Iron concentration reduced, and mRNA expression of ferroportin increased in macrophages from LysM-Cre FthKO mice. HFD-induced obesity was lower in LysM-Cre FthKO mice than in WT mice at 12 weeks (body weight (g); KO 34.6 ± 5.6 vs. WT 40.1 ± 5.2). mRNA expression of inflammatory cytokines, infiltrated macrophages, and oxidative stress increased in the adipose tissue of WT mice with HFD, but was not elevated in LysM-Cre FthKO mice with HFD. However, WT mice with HFD had elevated iron concentration in adipose tissue and spleen, which was not observed in LysM-Cre FthKO mice with HFD (adipose (μmol Fe/g protein); KO 1496 ± 479 vs. WT 2316 ± 866, spleen (μmol Fe/g protein); KO 218 ± 54 vs. WT 334 ± 83). Moreover, HFD administration impaired both glucose tolerance and insulin sensitivity in WT mice, which was ameliorated in LysM-Cre FthKO mice. In addition, energy expenditure, mRNA expression of thermogenic genes, and body temperature were higher in KO mice with HFD than WT mice with HFD. In vitro experiments showed that iron content was reduced, and LPS-induced TNF-α mRNA upregulation was inhibited in a macrophage cell line transfected with Fth siRNA. Conclusions/interpretation Deletion of macrophage H-ferritin suppresses the inflammatory response by reducing intracellular iron levels, resulting in the prevention of HFD-induced obesity and diabetes. The findings from this study highlight macrophage iron levels as a potential therapeutic target for obesity and diabetes

Proton pump inhibitors block iron absorption through direct regulation of hepcidin via the aryl hydrocarbon receptor-mediated pathway

Proton pump inhibitors (PPIs) have been used worldwide to treat gastrointestinal disorders. A recent study showed that long-term use of PPIs caused iron deficiency; however, it is unclear whether PPIs affect iron metabolism directly. We investigated the effect of PPIs on the peptide hepcidin, an important iron regulatory hormone. First, we used the FDA Adverse Event Reporting System database and analyzed the influence of PPIs. We found that PPIs, as well as H2 blockers, increased the odds ratio of iron-deficient anemia. Next, HepG2 cells were used to examine the action of PPIs and H2 blockers on hepcidin. PPIs augmented hepcidin expression, while H2 blockers did not. In fact, the PPI omeprazole increased hepcidin secretion, and omeprazole-induced hepcidin upregulation was inhibited by gene silencing or the pharmacological inhibition of the aryl hydrocarbon receptor. In mouse experiments, omeprazole also increased hepatic hepcidin mRNA expression and blood hepcidin levels. In mice treated with omeprazole, protein levels of duodenal and splenic ferroportin decreased. Taken together, PPIs directly affect iron metabolism by suppressing iron absorption through the inhibition of duodenal ferroportin via hepcidin upregulation. These findings provide a new insight into the molecular mechanism of PPI-induced iron deficiency

Atopic Dermatitis in Mouth Breathers

As mouth breathing is associated with asthma and otitis media, it may be associated with other diseases. Therefore, this population-based cross-sectional study evaluated the association of mouth breathing with the prevalences of various diseases in children. Preschool children older than 2 years were included. A questionnaire was given to parents/guardians at 13 nurseries in Tokushima City. There were 468 valid responses (45.2%). We defined a subject as a mouth breather in daytime (MBD) if they had 2 or more positive items among the 3 following items: “breathes with mouth ordinarily,” “mouth is open ordinarily,” and “mouth is open when chewing.” We defined subjects as mouth breathers during sleep (MBS) if they had 2 or more positive items among the following 3 items: “snoring,” “mouth is open during sleeping,” and “mouth is dry when your child gets up.” The prevalences of MBD and MBS were 35.5%and 45.9%, respectively. There were significant associations between MBD and atopic dermatitis (odds ratio [OR]: 2.4, 95% confidence interval [CI]: 1.4–4.2), MBS and atopic dermatitis (OR: 2.4, 95% CI: 1.3–4.2), and MBD and asthma (OR: 2.2, 95% CI: 1.2–4.0). After adjusting for history of asthma and allergic rhinitis; family history of atopic dermatitis, asthma, and allergic rhinitis; and nasal congestion; both MBD (OR: 2.6, 95% CI: 1.3–5.4) and MBS (OR: 4.1, 95% CI: 1.8–9.2) were significantly associated with atopic dermatitis. In preschool children older than 2 years, both MBD and MBS may be associated with the onset or development of atopic dermatitis

Diphenhydramine against cisplatin nephrotoxicity

Cisplatin is widely used as an anti-tumor drug for the treatment of solid tumors. Unfortunately, it causes nephrotoxicity as a critical side effect, limiting its use, given that no preventive drug against cisplatin-induced nephrotoxicity is currently available. This study identified that a previously developed drug, diphenhydramine, may provide a novel treatment for cisplatin-induced nephrotoxicity based on the results of the analysis of medical big data. We evaluated the actual efficacy of diphenhydramine via in vitro and in vivo experiments in a mouse model. Diphenhydramine inhibited cisplatin-induced cell death in renal proximal tubular cells. Mice administered cisplatin developed kidney injury with renal dysfunction (plasma creatinine: 0.43 ± 0.04 mg/dl vs 0.15 ± 0.01 mg/dl, p<0.01) and showed augmented oxidative stress, increased apoptosis, elevated inflammatory cytokines, and mitogen-activated protein kinases activation; however, most of these symptoms were suppressed by treatment with diphenhydramine. Further, the renal concentration of cisplatin was attenuated in diphenhydramine-treated mice (platinum content: 70.0 ± 3.3 µg/g dry kidney weight vs 53.4 ± 3.6 µg/g dry kidney weight, p<0.05). Importantly, diphenhydramine did not influence or interfere with the anti-tumor effect of cisplatin in any of the in vitro or in vivo experiments. Moreover, a retrospective clinical study of 1467 cancer patients treated with cisplatin showed that patients who had used diphenhydramine exhibited less acute kidney injury than patients who had not used diphenhydramine (6.1 % vs 22.4 %, p<0.05). Thus, diphenhydramine demonstrated efficacy as a novel preventive medicine against cisplatin-induced nephrotoxicity

Drug Repositioning for Cardiac Arrest

The survival rate of cardiac arrest patients is less than 10%; therefore, development of a therapeutic strategy that improves their prognosis is necessary. Herein, we searched data collected from medical facilities throughout Japan for drugs that improve the survival rate of cardiac arrest patients. Candidate drugs, which could improve the prognosis of cardiac arrest patients, were extracted using “TargetMine,” a drug discovery tool. We investigated whether the candidate drugs were among the drugs administered within 1 month after cardiac arrest in data of cardiac arrest cases obtained from the Japan Medical Data Center. Logistic regression analysis was performed, with the explanatory variables being the presence or absence of the administration of those candidate drugs that were administered to ≥10 patients and the objective variable being the “survival discharge.” Adjusted odds ratios for survival discharge were calculated using propensity scores for drugs that significantly improved the proportion of survival discharge; the influence of covariates, such as patient background, medical history, and treatment factors, was excluded by the inverse probability-of-treatment weighted method. Using the search strategy, we extracted 165 drugs with vasodilator activity as candidate drugs. Drugs not approved in Japan, oral medicines, and external medicines were excluded. Then, we investigated whether the candidate drugs were administered to the 2,227 cardiac arrest patients included in this study. The results of the logistic regression analysis showed that three (isosorbide dinitrate, nitroglycerin, and nicardipine) of seven drugs that were administered to ≥10 patients showed significant association with improvement in the proportion of survival discharge. Further analyses using propensity scores revealed that the adjusted odds ratios for survival discharge for patients administered isosorbide dinitrate, nitroglycerin, and nicardipine were 3.35, 5.44, and 4.58, respectively. Thus, it can be suggested that isosorbide dinitrate, nitroglycerin, and nicardipine could be novel therapeutic agents for improving the prognosis of cardiac arrest patients

Shortest-Path Network Analysis Is a Useful Approach toward Identifying Genetic Determinants of Longevity

Background Identification of genes that modulate longevity is a major focus of aging-related research and an area of intense public interest. In addition to facilitating an improved understanding of the basic mechanisms of aging, such genes represent potential targets for therapeutic intervention in multiple age-associated diseases, including cancer, heart disease, diabetes, and neurodegenerative disorders. To date, however, targeted efforts at identifying longevity-associated genes have been limited by a lack of predictive power, and useful algorithms for candidate gene-identification have also been lacking. Methodology/Principal Findings We have utilized a shortest-path network analysis to identify novel genes that modulate longevity in Saccharomyces cerevisiae. Based on a set of previously reported genes associated with increased life span, we applied a shortest-path network algorithm to a pre-existing protein–protein interaction dataset in order to construct a shortest-path longevity network. To validate this network, the replicative aging potential of 88 single-gene deletion strains corresponding to predicted components of the shortest-path longevity network was determined. Here we report that the single-gene deletion strains identified by our shortest-path longevity analysis are significantly enriched for mutations conferring either increased or decreased replicative life span, relative to a randomly selected set of 564 single-gene deletion strains or to the current data set available for the entire haploid deletion collection. Further, we report the identification of previously unknown longevity genes, several of which function in a conserved longevity pathway believed to mediate life span extension in response to dietary restriction. Conclusions/Significance This work demonstrates that shortest-path network analysis is a useful approach toward identifying genetic determinants of longevity and represents the first application of network analysis of aging to be extensively validated in a biological system. The novel longevity genes identified in this study are likely to yield further insight into the molecular mechanisms of aging and age-associated disease