95 research outputs found

    Grain boundary diffusion of W in lower mantle phase with implications for isotopic heterogeneity in oceanic island basalts by core-mantle interactions

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    Tungsten isotopes provide important constraints on the ocean-island basalt (OIB) source regions. Recent analyses of μ182W in modern basalts with high 3He/4He originating from the core-mantle boundary region reveal two distinct features: positive μ182W in Phanerozoic flood basalts indicating the presence of primordial reservoir, and negative μ182W in modern OIBs. One possibility to produce large variations in μ182W is interaction between the mantle and outer core. Here, we report grain boundary diffusion of W in lower mantle phases. High pressure experimental results show that grain boundary diffusion of W is fast and strongly temperature dependent. Over Earth's history, diffusive transport of W from the core to the lowermost mantle may have led to significant modification of the W isotopic composition of the lower mantle at length scales exceeding one kilometer. Such grain boundary diffusion can lead to large variations in μ182W in modern basalts as a function of the distance of their source regions from the core mantle boundary. Modern oceanic island basalts from Hawaii, Samoa and Iceland exhibit negative μ182W and likely originated from the modified isotope region just above the core-mantle boundary, whereas those with positive μ182W could be derived from the thick Large Low Shear Velocity Provinces (LLSVPs) far from the core-mantle boundary (CMB). When highly-oxidized slabs accumulate at the CMB oxidizing the outer core at the interface, a large W flux with negative μ182W can be added to the silicate mantle. As a result, the source region of the OIB would be effectively modified to a negative μ182W

    Parasitic Pathogens Associated with Diarrhoea in Mombasa, Kenya

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    A microscopic examination of a faecal specimens was designed to identify the enteropathogenic parasites in the diarrhoeal stool specimens in which neither enteropathogenic bacteria nor rotavirus was isolated in Caost Provincial General Hospital, Mombasa, Kenya. The parasites incriminated as causes of diarrhoea were Entamoeba histolytica, Giardia lamblia, Trichuris trichiura, hookworm and Ascaris lumbricoides. The cysts and ova of these parasites, however, were present with equal frequency in diarrhoeal, semi-formed and formed stool specimens, except the trophozoites of E. histolytica. The role of parasites in causation of diarrhoea is difficult to evaluate by the routine stool examination for parasites

    ONO-1301, a Sustained-Release Prostacyclin Analog, Ameliorates the Renal Alterations in a Mouse Type 2 Diabetes Model Possibly Through Its Protective Effects on Mesangial Cells

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    Diabetic nephropathy is the most common pathological disorder predisposing patients to end-stage renal disease. Considering the increasing prevalence of type 2 diabetes mellitus worldwide, novel therapeutic approaches are urgently needed. ONO-1301 is a novel sustained-release prostacyclin analog that inhibits thromboxane A2 synthase. Here we examined the therapeutic effects of the intermittent administration of slow-release ONO-1301 (SR-ONO) on diabetic nephropathy in obese type 2 diabetes mice, as well as its direct effects on mesangial cells. The subcutaneous injection of SR-ONO (3mg/kg) every 3 wks did not affect the obesity or hyperglycemia in the db/db obese mice used as a model of type 2 diabetes, but it significantly ameliorated their albuminuria, glomerular hypertrophy, glomerular accumulation of type IV collagen, and monocyte/macrophage infiltration, and also the increase of TGF-β1, α-smooth muscle actin (α-SMA) and MCP-1 compared to vehicle treatment. In cultured mouse mesangial cells, ONO-1301 concentration-dependently suppressed the increases in TGF-β, type IV collagen, α-SMA, MCP-1 and fibronectin induced by high ambient glucose, at least partly through prostacyclin (PGI2) receptor-mediated signaling. Taken together, these results suggest the potential therapeutic efficacy of the intermittent administration of SR-ONO against type 2 diabetic nephropathy, possibly through protective effects on mesangial cells

    Infrequent RAS mutation is not associated with specific histological phenotype in gliomas

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    BACKGROUND: Mutations in driver genes such as IDH and BRAF have been identified in gliomas. Meanwhile, dysregulations in the p53, RB1, and MAPK and/or PI3K pathways are involved in the molecular pathogenesis of glioblastoma. RAS family genes activate MAPK through activation of RAF and PI3K to promote cell proliferation. RAS mutations are a well-known driver of mutation in many types of cancers, but knowledge of their significance for glioma is insufficient. The purpose of this study was to reveal the frequency and the clinical phenotype of RAS mutant in gliomas. METHODS: This study analysed RAS mutations and their clinical significance in 242 gliomas that were stored as unfixed or cryopreserved specimens removed at Kyoto University and Osaka National Hospital between May 2006 and October 2017. The hot spots mutation of IDH1/2, H3F3A, HIST1H3B, and TERT promoter and exon 2 and exon 3 of KRAS, HRAS, and NRAS were analysed with Sanger sequencing method, and 1p/19q codeletion was analysed with multiplex ligation-dependent probe amplification. DNA methylation array was performed in some RAS mutant tumours to improve accuracy of diagnosis. RESULTS: RAS mutations were identified in four gliomas with three KRAS mutations and one NRAS mutation in one anaplastic oligodendroglioma, two anaplastic astrocytomas (IDH wild-type in each), and one ganglioglioma. RAS-mutant gliomas were identified with various types of glioma histology. CONCLUSION: RAS mutation appears infrequent, and it is not associated with any specific histological phenotype of glioma

    Randomized trial of an intensified, multifactorial intervention in patients with advanced‐stage diabetic kidney disease: Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT‐Japan)

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    Aims/Introduction We evaluated the efficacy of multifactorial intensive treatment (IT) on renal outcomes in patients with type 2 diabetes and advanced‐stage diabetic kidney disease (DKD). Materials and Methods The Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT‐Japan) is a multicenter, open‐label, randomized controlled trial with a 5‐year follow‐up period. We randomly assigned 164 patients with advanced‐stage diabetic kidney disease (urinary albumin‐to‐creatinine ratio ≥300 mg/g creatinine, serum creatinine level 1.2–2.5 mg/dL in men and 1.0–2.5 mg/dL in women) to receive either IT or conventional treatment. The primary composite outcome was end‐stage kidney failure, doubling of serum creatinine or death from any cause, which was assessed in the intention‐to‐treat population. Results The IT tended to reduce the risk of primary end‐points as compared with conventional treatment, but the difference between treatment groups did not reach the statistically significant level (hazard ratio 0.69, 95% confidence interval 0.43–1.11; P = 0.13). Meanwhile, the decrease in serum low‐density lipoprotein cholesterol level and the use of statin were significantly associated with the decrease in primary outcome (hazard ratio 1.14; 95% confidence interval 1.05–1.23, P Conclusions The risk of kidney events tended to decrease by IT, although it was not statistically significant. Lipid control using statin was associated with a lower risk of adverse kidney events. Further follow‐up study might show the effect of IT in patients with advanced diabetic kidney disease

    Association between initial body temperature on hospital arrival and neurological outcome among patients with out-of-hospital cardiac arrest: a multicenter cohort study (the CRITICAL study in Osaka, Japan)

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    [Background] The association between spontaneous initial body temperature on hospital arrival and neurological outcomes has not been sufficiently studied in patients after out-of-hospital cardiac arrest (OHCA). [Methods] From the prospective database of the Comprehensive Registry of Intensive Care for OHCA Survival (CRITICAL) study in Osaka, Japan, we enrolled all patients with OHCA of medical origin aged > 18 years for whom resuscitation was attempted and who were transported to participating hospitals between 2012 and 2019. We excluded patients who were not witnessed by bystanders and treated by a doctor car or helicopter, which is a car/helicopter with a physician. The patients were categorized into three groups according to their temperature on hospital arrival: ≤35.9 °C, 36.0–36.9 °C (normothermia), and ≥ 37.0 °C. The primary outcome was 1-month survival, with a cerebral performance category of 1 or 2. Multivariable logistic regression analyses were performed to evaluate the association between temperature and outcomes (normothermia was used as the reference). We also assessed this association using cubic spline regression analysis. [Results] Of the 18, 379 patients in our database, 5014 witnessed adult OHCA patients of medical origin from 16 hospitals were included. When analyzing 3318 patients, OHCA patients with an initial body temperature of ≥37.0 °C upon hospital arrival were associated with decreased favorable neurological outcomes (6.6% [19/286] odds ratio, 0.51; 95% confidence interval, 0.27–0.95) compared to patients with normothermia (16.4% [180/1100]), whereas those with an initial body temperature of ≤35.9 °C were not associated with decreased favorable neurological outcomes (11.1% [214/1932]; odds ratio, 0.78; 95% confidence interval, 0.56–1.07). The cubic regression splines demonstrated that a higher body temperature on arrival was associated with decreased favorable neurological outcomes, and a lower body temperature was not associated with decreased favorable neurological outcomes. [Conclusions] In adult patients with OHCA of medical origin, a higher body temperature on arrival was associated with decreased favorable neurologic outcomes

    Clinical impact of albuminuria and glomerular filtration rate on renal and cardiovascular events, and all-cause mortality in Japanese patients with type 2 diabetes

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    Background: The number of patients suffering from diabetic nephropathy resulting in end-stage kidney disease is increasing worldwide. In clinical settings, there are limited data regarding the impact of the urinary albumin-to-creatinine ratio (UACR) and reduced estimated glomerular filtration rate (eGFR) on renal and cardiovascular outcomes and all-cause mortality. Methods: We performed a historical cohort study of 4328 Japanese participants with type 2 diabetes from 10 centers. Risks for renal events (requirement for dialysis or transplantation, or half reduction in eGFR), cardiovascular events (cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke), and all-cause mortality were assessed according to UACR and eGFR levels. Results: During follow-up (median 7.0 years, interquartile range 3.0-8.0 years), 419 renal events, 605 cardiovascular events and 236 deaths occurred. The UACR levels increased the risk and the adjusted hazard ratios for these three events. In addition to the effects of UACR levels, eGFR stages significantly increased the adjusted hazard ratios for renal events and all-cause mortality, especially in patients with macroalbuminuria. Diabetic nephropathy score, based on the prognostic factors, well predicted incidence rates per 1000 patient/year for each event. Conclusions: Increased UACR levels were closely related to the increase in risks for renal, cardiovascular events and all-cause mortality in Japanese patients with type 2 diabetes, whereas the association between high levels of UACR and reduced eGFR was a strong predictor for renal events. © 2013 Japanese Society of Nephrology
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