245 research outputs found
A Unique Feature of the Asian Summer Monsoon Response to Global Warming: The Role of Different Land–Sea Thermal Contrast Change between the Lower and Upper Troposphere
Recent studies indicate that the view of a general weakening of the monsoon circulation in a warmer climate cannot be simply applied in the Asian monsoon regions. To understand the Asian summer monsoon response to global warming, idealized multi-model experiments are analyzed. In the coupled model response to increased CO2, monsoon westerlies in the lower troposphere are shifted poleward and slightly strengthened over land including South Asia and East Asia, while the tropical easterly jet in the upper troposphere are broadly weakened. The different circulation responses between the lower and upper troposphere is associated with vertically opposite changes in the meridional temperature gradient (MTG) between the Eurasian continent and the tropical Indian Ocean, with a strengthening (weakening) in the lower (upper) troposphere. Atmospheric model experiments to separate the effects of CO2 radiative forcing and sea surface temperature warming reveal that the strengthened MTG in the lower troposphere is explained by the CO2 forcing. On a global perspective, CO2-induced enhancement of the land–sea thermal contrast and resultant circulation changes are the most influential in the South Asian monsoon. This study emphasizes an important role of the land warming on the Asian monsoon response to global warming
気候モデルを用いたモンスーン地域の降水の将来変化と予測不確実性に関する研究
この博士論文は、全文公表に適さないやむを得ない事由があり要約のみを公表していましたが、解消したため、令和2(2020)年6月3日に全文を公表しました。筑波大学 (University of Tsukuba)201
Nutrient concentrations of precipitation, throughfall, soil water, groundwater, hyporheic water and stream water in a konara oak (Quercus serrata) forest
中国山地中央部に位置する鳥取大学・蒜山の森のコナラ林流域において, 降水, 林内雨, 土壌水, 地下水, 河床間隙水, 及び河川水の濃度分布を調べた. 2010年4月から2012年8月までの間に, 月に1~5回の頻度でこれらの水を採取し, 窒素とリンの濃度を分析した. 中央値に着目すると, 溶存態窒素の濃度は, 降水(0.39~0.59mg/l)よりも林内雨(0.60~0.67mg/l)はわずかに高く, 土壌水(1.92~2.93mg/l)はさらに高かったのに対し, 地下水(0.13~0.07mg/l), 河床間隙水(0.23~0.31mg/l), 及び河川水(0.20mg/l)は低かった. 溶存態リンの濃度は, 降水(0.003~0.004mg/l)よりも林内雨(0.015~0.039mg/l)で顕著に高かったのに対し, 土壌水(0.002mg/l), 地下水(0.001~0.002mg/l), 河床間隙水(0.001mg/l), 及び河川水(0.002mg/l)で低かった. 懸濁態の濃度については, 窒素もリンも林内雨で高く, 河川水で低かった. 全窒素と全リンについては, いずれも降水(全窒素:0.47~1.08, 全リン:0.007~0.019mg/l)よりも河川水(全窒素:0.27, 全リン:0.006mg/l)の方が低かった. これらの結果は, 当該地域の物質循環や水環境の研究にとって重要なバックグランドデータとなりうる
744-3 Inhibition of Nitric Oxide Synthesis does not Increase Cardiac Contractile Response but Reduces Coronary Blood Flow Response to β-Adrenergic Stimulation in Normal Dogs
Although the induction of nitric oxide (NO) synthesis has been implicated as a cause of cytokine-induced depression of cardiac β-adrenergic responsiveness. whether the NO system constitutively present in the normal myocardium plays a role in its physiologic response to β-adrenergic stimulation in vivoremains controversial. Accordingly, we examined the effects of low and high doses of NW-nitro-L-arginine methyl ester (L-NAME)(10 and 100 μg/kg/min for 10 min), an NO synthase inhibitor, administered into left circumflex coronary artery (LCX) on responses of peak left ventricular (LV) dP/dt, regional wall thickening in LCX region and LCX blood flow to graded intracoronary (IC) doses of isoproterenol (ISO:0.002 to 0.016 μg/kg/min) in 7 anesthetized dogs. IC L-NAME was associated with dose-related reductions in IC acetylcholine-induced coronary vasodilation. Effects of L-NAME on ISO-induced changes are shown:baselineISO:0.0020.0040.008.0016Peak LV dP/dt (mmHg/sec) (n=7)control2029±1362586±1922820±2003309±2554120±419*low L-NAME2171±1492566±1762894±2063214±2233707±250*high L-NAME2114±1662326±1932560±1523014±1403354±171*Wall thickening (%) (n=2)control22±725±629±533±735±9low L-NAME25±1125±1528±1931±1836±21high L-NAME28±1725±1525±1531±1934±15LCX blood flow (ml/min)(n=7)control33±648±752±661±870±9*low L-NAME36±741±844±947±852±9*high L-NAME33±736±838±740±748±8*mean ± SEM*p<0.05Thus, inhibition of NO synthesis by L-NAME did not change baseline contractility nor did it increase its response to ISO. It also did not alter baseline blood flow, but reduced significantly its response to ISO. These data strongly suggest that the NO system in the normal myocardium does not modulate contractility, but NO formation in the vasculature contributes to the β-adrenergic coronary vasodilation
PPARγ Ligand as a Promising Candidate for Colorectal Cancer Chemoprevention: A Pilot Study
Activating synthetic ligands for peroxisome proliferator-activated receptor gamma (PPARγ), such as pioglitazone, are commonly used to treat persons with diabetes mellitus with improvement of insulin resistance. Several reports have clearly demonstrated that PPARγ ligands could inhibit colorectal cancer cell growth and induce apoptosis. Meanwhile, aberrant crypt foci (ACF) have come to be established as a biomarker of the risk of CRC in azoxymethane-treated mice and rats. In humans, ACF can be detected using magnifying colonoscopy. Previously, CRC and adenoma were used as a target for chemopreventive agents, but it needs a long time to evaluate, however, ACF can be a surrogate marker of CRC even for a brief period. In this clinical study, we investigated the chemopreventive effect of pioglitazone on the development of human ACF as a surrogate marker of CRC. Twenty-nine patients were divided into two groups, 20 were in the endoscopically normal control group and 9 were in the pioglitazone (15 mg/day) group, and ACF and adenoma were examined before and after 1-month treatment. The number of ACF was significantly decreased (5.8 ± 1.1 to 3.3 ± 2.3) after 1 month of pioglitazone treatment, however, there was no significant change in the number of crypts/ACF or in the number and size of adenomas. Pioglitazone may have a clinical application as a cancer-preventive drug. This investigation is just a pilot study, therefore, further clinical studies are needed to show that the PPARγ ligand may be a promising candidate as a chemopreventive agent for colorectal carcinogenesis
Tensile And Impact Properties Of Pulverized Oil Palm Fiber Reinforced Polypropylene Composites : A Comparison Study With Wood Fiber Reinforced Polypropylene Composites
The comparison of tensile and impact properties between the fiber extracted from Malaysia’s oil palm plantation wastes and residues and wood fiber that are going to be
used as reinforcing agent in polymer composite materials is the main focus of this study.For that purpose,10 wt.% and 25 wt.% of Malaysian oil palm fiber (OPF) extracted from oil palm empty fruit bunches (OPEFB) was incorporated with polypropylene (PP) and maleated polypropylene (MAPP) to produce injection-molded composite materials.For comparison purposes,virgin PP and wood fiber reinforced polymer composites (WPC)were also fabricated as benchmark samples.Firstly,tensile test was performed for all three samples;virgin PP,OPF/PP and WPC in order to investigate the effect of fiber loading on composite materials.From the tensile test result,25 wt.% of fiber loading produced higher tensile properties than 10 wt.% of fiber loading.Moreover,the obtained OPF/PP composites showed comparable properties with the WPC material.Furthermore,the effect of fiber size on tensile and impact properties of both OPF/PP and WPC composite was investigated.As the results,the utilization of OPF into PP matrix demonstrated almost similar tensile and impact strength as WPC material.The equality of properties between OPF/PP composites and WPC indicates the potential of wastes and residual materials such as OPF to be broadly utilized in the production of composite
materials
Endoscopic therapy using an endoscopic variceal ligation for minute cancer of the esophagogastric junction complicated with esophageal varices: a case report
<p>Abstract</p> <p>Introduction</p> <p>Standard endoscopic mucosal resection or endoscopic submucosal dissection is a procedure for patients with minute cancers, complicated with esophageal varices that puts them at high risk of bleeding.</p> <p>Case presentation</p> <p>We present the case of a 77-year-old Japanese man with alcoholic cirrhosis who underwent a routine endoscopy examination as a screening procedure for esophageal varices and was incidentally diagnosed as having minute cancer of the esophagogastric junction with esophageal varices. Endoscopic ultrasonography findings suggested that the minute cancer was a non-invasive carcinoma (carcinoma <it>in situ</it>) and a 2 mm in diameter blood vessel, feeding the esophageal varices, pierced the lesion. Following the examination, we carried out endoscopic treatment of the minute cancer and esophageal varices. Endoscopic variceal ligation was performed using a pneumo-activated device (Sumitomo Bakelite, Tokyo, Japan). Two years after the treatment, during the follow-up endoscopic examination on the patient, recurrence of carcinoma was not detected endoscopically or histologically.</p> <p>Conclusion</p> <p>Endoscopic therapy using an endoscopic variceal ligation device for minute cancer of the esophagogastric junction, complicated with esophageal varices, may be an acceptable and easily applicable method.</p
Penetration of the sigmoid colon to the posterior uterine wall secondary to diverticulitis: a case report
<p>Abstract</p> <p>Introduction</p> <p>Penetration of the colon to the posterior uterine wall secondary to diverticulitis is unusual, with diagnostic methods not yet established. Non-invasive imaging, such as computed tomography and magnetic resonance imaging may help to establish a proper diagnosis, but confirmation may be reached only after surgical exploration.</p> <p>Case presentation</p> <p>We report the case of a 78-year-old Japanese woman who presented with a low grade fever and mild diarrhea which occurred two or three times a week. Computed tomography and magnetic resonance imaging demonstrated a capsular lesion including an air structure with a diameter of 5 cm, between the posterior aspect of the uterine body and the sigmoid colon. A gastrograffin enema and colonoscopy demonstrated a giant diverticulum of the sigmoid colon with no evidence of malignancy. These data confirmed the diagnosis of diverticulitis complicated by a giant diverticulum. Because of a relapsing fever after therapy with antibiotics, the patient had en bloc surgical treatment of the uterus, fallopian tubes, ovaries and sigmoid colon, the organs involved in the diverticulitis, followed by an uneventful recovery.</p> <p>Conclusion</p> <p>This is a rare case report of penetration of the sigmoid colon to the posterior uterine wall secondary to diverticulitis.</p
Next-generation survey sequencing and the molecular organization of wheat chromosome 6B.
コムギのゲノム配列の概要解読に成功 -コムギの新品種開発の加速化に期待-. 京都大学プレスリリース. 2014-07-24.Common wheat (Triticum aestivum L.) is one of the most important cereals in the world. To improve wheat quality and productivity, the genomic sequence of wheat must be determined. The large genome size (∼17 Gb/1 C) and the hexaploid status of wheat have hampered the genome sequencing of wheat. However, flow sorting of individual chromosomes has allowed us to purify and separately shotgun-sequence a pair of telocentric chromosomes. Here, we describe a result from the survey sequencing of wheat chromosome 6B (914 Mb/1 C) using massively parallel 454 pyrosequencing. From the 4.94 and 5.51 Gb shotgun sequence data from the two chromosome arms of 6BS and 6BL, 235 and 273 Mb sequences were assembled to cover ∼55.6 and 54.9% of the total genomic regions, respectively. Repetitive sequences composed 77 and 86% of the assembled sequences on 6BS and 6BL, respectively. Within the assembled sequences, we predicted a total of 4798 non-repetitive gene loci with the evidence of expression from the wheat transcriptome data. The numbers and chromosomal distribution patterns of the genes for tRNAs and microRNAs in wheat 6B were investigated, and the results suggested a significant involvement of DNA transposon diffusion in the evolution of these non-protein-coding RNA genes. A comparative analysis of the genomic sequences of wheat 6B and monocot plants clearly indicated the evolutionary conservation of gene contents
TAK1 inhibition in myeloma
Along with the tumor progression, the bone marrow microenvironment is skewed in multiple myeloma (MM), which underlies the unique pathophysiology of MM and confers aggressiveness and drug resistance in MM cells. TGF-β-activated kinase-1 (TAK1) mediates a wide range of intracellular signaling pathways. We demonstrate here that TAK1 is constitutively overexpressed and phosphorylated in MM cells, and that TAK1 inhibition suppresses the activation of NF-κB, p38MAPK, ERK and STAT3 in order to decrease the expression of critical mediators for MM growth and survival, including PIM2, MYC, Mcl-1, IRF4, and Sp1, along with a substantial reduction in the angiogenic factor VEGF in MM cells. Intriguingly, TAK1 phosphorylation was also induced along with upregulation of vascular cell adhesion molecule-1 (VCAM-1) in bone marrow stromal cells (BMSC) in cocultures with MM cells, which facilitated MM cell-BMSC adhesion while inducing IL-6 production and receptor activator of nuclear factor κ-Β ligand (RANKL) expression by BMSC. TAK1 inhibition effectively impaired MM cell adhesion to BMSC to disrupt the support of MM cell growth and survival by BMSC. Furthermore, TAK1 inhibition suppressed osteoclastogenesis enhanced by RANKL in cocultures of bone marrow cells with MM cells, and restored osteoblastic differentiation suppressed by MM cells or inhibitory factors for osteoblastogenesis overproduced in MM. Finally, treatment with the TAK1 inhibitor LLZ1640-2 markedly suppressed MM tumor growth and prevented bone destruction and loss in mouse MM models. Therefore, TAK1 inhibition may be a promising therapeutic option targeting not only MM cells but also the skewed bone marrow microenvironment in MM
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