108 research outputs found
Effects of improved sodium uptake ability on grain yields of rice plants under low potassium supply
Sodium uptake is a factor that determines potassium use efficiency in plants as sodium can partially replace potassium in plant cells. Rice (Oryza sativa) roots usually exclude sodium but actively take it up when the plant is deficient in potassium. In rice roots, a sodium transporter OsHKT2;1 mediates active sodium uptake. We previously revealed that variation in the expression of OsHKT2;1 underlies the variation in sodium accumulation between a low-sodium-accumulating indica cultivar, IR64, and a high-sodium-accumulating japonica cultivar, Koshihikari. In the present study, we evaluated IR64 and its near-isogenic line IR64-K carrying OsHKT2;1 and neighboring genes inherited from Koshihikari for grain yield. IR64-K had a greater average grain yield and harvest index than IR64 in a pot culture experiment with three levels of potassium fertilizer. The differences were most significant under treatment without the potassium fertilizer. IR64-K also showed a slightly higher grain yield than IR64 when grown in a paddy field without applying the potassium fertilizer. These results suggest that enhanced sodium uptake ability improves the grain yield of rice plants under low-potassium-input conditions
A Study of Lecture Meetings and Childcare Activities in The Kindergarten
本研究の目的は、子育て支援の一環として試みた講演会や親子での活動が保護者にどのように受け止められ活動の後で変化をもたらしたかをアンケート調査し、今後の講演会や親子活動のあり方を考える上での基礎資料を得ることである。その結果、親子が一緒に活動するものや内容が具体的で保護者のニーズに対応したものの方が、参加率が高く、男女共7割以上の保護者が参加する前より考え方を変化させている。そして、親子参加型の子育て支援が望まれていることが明らかになった。The purpose of this study was to examine the effect of our support of childcare activities: lecture meetings and activities with parents and children. Parents were asked how they accepted these activities and what changes were brought by them. The results should that many parents took part in activities with children, and lecture meetings which had practical and concrete contents. And more than 70% of parents have changed their way of thinking
Multiple myeloma with high adenosine deaminase expression
A 50-year-old man with immunoglobulin A type multiple myeloma (MM) was referred to our hospital after bortezomib therapy. He had high alkaline phosphatase and lactate dehydrogenase levels. Computed tomography showed osteolytic and osteoblastic bone lesions. Response to salvage chemotherapy was temporary, and he developed a right pleural effusion with high adenosine deaminase (ADA) levels. He died from bleeding associated with a pelvic bone fracture 9 months later. ADA mRNA expression and ADA secretion of the MM cells from the patient were higher than those from myeloma cell lines tested. Clinical relevance of high ADA expression in MM cells is warranted
Association of an overlap syndrome of autoimmune hepatitis and primary biliary cirrhosis with cytomegalovirus infection
A 63-year-old woman, who presented with severe jaundice and elevated serum conjugated bilirubin level, denied alcohol and drug use and showed no evidence of viral hepatitis. Based on clinical and laboratory features, she was diagnosed with autoimmune hepatitis with primary biliary cirrhosis. Hematological and immunochemical assays, radiographic imaging, clinical examination, and liver biopsy were conducted. Laboratory results were the following: negative for fluorescence antinuclear antibody, negative for antismooth muscle antibodies but positive for antinuclear antibody (enzyme-linked immunosorbent assay) and antimitochondrial M2 antibody, high titers of serum globulin, and positive for cytomegalovirus IgM. Liver biopsy showed submassive lobular necrosis, inflammation with broad areas of parenchymal collapse, and chronic nonsuppurative destructive cholangitis. The patient responded well to corticosteroid therapy. This case might illustrate an association between cytomegalovirus infection and the occurrence of autoimmune hepatitis
Novel antimyeloma therapeutic option with inhibition of the HDAC1-IRF4 axis and PIM kinase
Multiple myeloma (MM) preferentially expands and acquires drug resistance in the bone marrow (BM). We herein examined the role of histone deacetylase 1 (HDAC1) in the constitutive activation of the master transcription factor IRF4 and the prosurvival mediator PIM2 kinase in MM cells. The knockdown or inhibition of HDAC1 by the class I HDAC inhibitor MS-275 reduced the basal expression of IRF4 and PIM2 in MM cells. Mechanistically, the inhibition of HDAC1 decreased IRF4 transcription through histone hyperacetylation and inhibiting the recruitment of RNA polymerase II at the IRF4 locus, thereby reducing IRF4-targeting genes, including PIM2. In addition to the transcriptional regulation of PIM2 by the HDAC1-IRF4 axis, PIM2 was markedly upregulated by external stimuli from BM stromal cells and interleukin-6 (IL-6). Upregulated PIM2 contributed to the attenuation of the cytotoxic effects of MS-275. Class I HDAC and PIM kinase inhibitors cooperatively suppressed MM cell growth in the presence of IL-6 and in vivo. Therefore, the present results demonstrate the potential of the simultaneous targeting of the intrinsic HDAC1-IRF4 axis plus externally activated PIM2 as an efficient therapeutic option for MM fostered in the BM
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
Class 1 HDAC-specific inhibition augments but HDAC6 inhibition mitigates CD38 upregulation in myeloma cells by interferon-α and all-trans retinoic acid
Glycolysis Inhibition Inactivates ABC Transporters to Restore Drug Sensitivity in Malignant Cells
Cancer cells eventually acquire drug resistance largely via the aberrant expression of ATP-binding cassette (ABC) transporters, ATP-dependent efflux pumps. Because cancer cells produce ATP mostly through glycolysis, in the present study we explored the effects of inhibiting glycolysis on the ABC transporter function and drug sensitivity of malignant cells. Inhibition of glycolysis by 3-bromopyruvate (3BrPA) suppressed ATP production in malignant cells, and restored the retention of daunorubicin or mitoxantrone in ABC transporter-expressing, RPMI8226 (ABCG2), KG-1 (ABCB1) and HepG2 cells (ABCB1 and ABCG2). Interestingly, although side population (SP) cells isolated from RPMI8226 cells exhibited higher levels of glycolysis with an increased expression of genes involved in the glycolytic pathway, 3BrPA abolished Hoechst 33342 exclusion in SP cells. 3BrPA also disrupted clonogenic capacity in malignant cell lines including RPMI8226, KG-1, and HepG2. Furthermore, 3BrPA restored cytotoxic effects of daunorubicin and doxorubicin on KG-1 and RPMI8226 cells, and markedly suppressed subcutaneous tumor growth in combination with doxorubicin in RPMI8226-implanted mice. These results collectively suggest that the inhibition of glycolysis is able to overcome drug resistance in ABC transporter-expressing malignant cells through the inactivation of ABC transporters and impairment of SP cells with enhanced glycolysis as well as clonogenic cells
RANKLが誘導する破骨細胞分化におけるROSの役割と、Febuxostatによる破骨細胞分化抑制効果
Receptor activator of NF-κB ligand (RANKL), a critical mediator of osteoclastogenesis, is upregulated in multiple myeloma (MM). The xanthine oxidase inhibitor febuxostat, clinically used for prevention of tumor lysis syndrome, has been demonstrated to effectively inhibit not only the generation of uric acid but also the formation of reactive oxygen species (ROS). ROS has been demonstrated to mediate RANKL-mediated osteoclastogenesis. In the present study, we therefore explored the role of cancer-treatment-induced ROS in RANKL-mediated osteoclastogenesis and the suppressive effects of febuxostat on ROS generation and osteoclastogenesis. RANKL dose-dependently induced ROS production in RAW264.7 preosteoclastic cells; however, febuxostat inhibited the RANKL-induced ROS production and osteoclast (OC) formation. Interestingly, doxorubicin (Dox) further enhanced RANKL-induced osteoclastogenesis through upregulation of ROS production, which was mostly abolished by addition of febuxostat. Febuxostat also inhibited osteoclastogenesis enhanced in cocultures of bone marrow cells with MM cells. Importantly, febuxostat rather suppressed MM cell viability and did not compromise Dox’s anti-MM activity. In addition, febuxostat was able to alleviate pathological osteoclastic activity and bone loss in ovariectomized mice. Collectively, these results suggest that excessive ROS production by aberrant RANKL overexpression and/or anticancer treatment disadvantageously impacts bone, and that febuxostat can prevent the ROS-mediated osteoclastic bone damage
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