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81.
A novel Na+‐Independent alanine‐serine‐cysteine transporter 1 inhibitor inhibits both influx and efflux of D‐Serine
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Katsuya Sakimura Kenji Nakao Masato Yoshikawa Motohisa Suzuki Haruhide Kimura 《Journal of neuroscience research》2016,94(10):888-895
NMDA receptor dysfunctions are hypothesized to underlie the pathophysiology of schizophrenia, and treatment with D‐serine (D‐Ser), an NMDA receptor coagonist, may improve the clinical symptoms of schizophrenia. Thus, upregulating the synaptic D‐Ser level is a novel strategy for schizophrenia treatment. Na+‐independent alanine‐serine‐cysteine transporter 1 (asc‐1) is a transporter responsible for regulating the extracellular D‐Ser levels in the brain. In this study, we discovered a novel asc‐1 inhibitor, (+)‐amino(1‐(3,5‐dichlorophenyl)‐3,5‐dimethyl‐1H‐pyrazol‐4‐yl)acetic acid (ACPP), and assessed its pharmacological profile. ACPP inhibited the D‐[3H]Ser uptake in human asc‐1‐expressing CHO cells and rat primary neurons with IC50 values of 0.72 ± 0.13 and 0.89 ± 0.30 μM, respectively. In accordance with the lower asc‐1 expression levels in astrocytes, ACPP did not inhibit D‐Ser uptake in rat primary astrocytes. In a microdialysis study, ACPP dose dependently decreased the extracellular D‐Ser levels in the rat hippocampus under the same conditions in which the asc‐1 inhibitor S‐methyl‐L‐cysteine (SMLC) increased it. To obtain insights into this difference, we conducted a D‐[3H]Ser efflux assay using asc‐1‐expressing CHO cells. ACPP inhibited D‐[3H]Ser efflux, whereas SMLC increased it. These results suggest that ACPP is a novel inhibitor of asc‐1. © 2016 Wiley Periodicals, Inc. 相似文献
82.
Kondo E Yasoda A Tsuji T Fujii T Miura M Kanamoto N Tamura N Arai H Kunieda T Nakao K 《Calcified tissue international》2012,90(4):307-318
Long bone abnormality (lbab/lbab) is a strain of dwarf mice. Recent studies revealed that the phenotype is caused by a spontaneous mutation in the Nppc gene, which encodes mouse C-type natriuretic peptide (CNP). In this study, we analyzed the chondrodysplastic skeletal phenotype
of lbab/lbab mice. At birth, lbab/lbab mice are only slightly shorter than their wild-type littermates. Nevertheless, lbab/lbab mice do not undergo a growth spurt, and their final body and bone lengths are only ~60% of those of wild-type mice. Histological
analysis revealed that the growth plate in lbab/lbab mice, especially the hypertrophic chondrocyte layer, was significantly thinner than in wild-type mice. Overexpression of
CNP in the cartilage of lbab/lbab mice restored their thinned growth plate, followed by the complete rescue of their impaired endochondral bone growth. Furthermore,
the bone volume in lbab/lbab mouse was severely decreased and was recovered by CNP overexpression. On the other hand, the thickness of the growth plate
of lbab/+ mice was not different from that of wild-type mice; accordingly, impaired endochondral bone growth was not observed in
lbab/+ mice. In organ culture experiments, tibial explants from fetal lbab/lbab mice were significantly shorter than those from lbab/+ mice and elongated by addition of 10−7 M CNP to the same extent as lbab/+ tibiae treated with the same dose of CNP. These results demonstrate that lbab/lbab is a novel mouse model of chondrodysplasia caused by insufficient CNP action on endochondral ossification. 相似文献
83.
K Matsushita K Uchida S Saigusa S Ide K Hashimoto Y Koike K Otake M Inoue K Tanaka M Kusunoki 《Journal of pediatric surgery》2012,47(7):1323-1330
Background/PurposeIncreased glycolysis is among the biochemical characteristics of cancerous tissue. The glucose transporter isoform 1 (GLUT1) gene encodes a key factor for glucose transport into cancerous tissue. However, the expression and functional significance of GLUT1 in neuroblastoma have not been fully characterized. Therefore, we investigated the association of GLUT1 expression with clinical outcomes in patients with neuroblastoma using immunohistochemical staining for GLUT1 in neuroblastoma tissues. We also assessed the efficacy of glycolysis inhibition as an anticancer treatment in neuroblastoma cell lines with altered expression of GLUT1.MethodsWe obtained total RNA from cancerous tissue by microdissection in 47 patients with neuroblastoma. GLUT1 expression levels were evaluated by quantitative real-time polymerase chain reaction. We analyzed the association of GLUT1 expression levels with clinical outcomes. We also examined changes in GLUT1 expression and proliferative responses in vitro using 4 neuroblastoma cell lines treated with a glycolysis inhibitor, 3-Bromopyruvate acid.ResultsElevated GLUT1 expression was associated with poor prognosis. Moreover, elevated GLUT1 expression independently predicted overall survival. Immunohistochemical analysis showed that GLUT1 expression tended to be localized to the centers of neuroblastoma cell nests. Our in vitro studies showed that 3-Bromopyruvate acid significantly suppressed the proliferation of neuroblastoma cells with high GLUT1 gene expression compared with those with low expression.ConclusionGlycolysis inhibitors are a potential therapeutic option for treating aggressive tumors expressing GLUT1. 相似文献
84.
K Okazaki T Yamaguchi K Tanaka M Notsu N Ogawa S Yano T Sugimoto 《Calcified tissue international》2012,91(4):286-296
Diabetes mellitus is known to be associated with osteoporotic fractures through a decrease in osteoblastic bone formation rather than an increase in osteoclastic bone resorption. However, its precise mechanism is unknown, and we examined whether or not high glucose or advanced glycation end products (AGEs), which play key roles in the pathogenesis and complications of diabetes, would affect the osteoblastic differentiation, growth, and apoptosis of mouse stromal ST2 cells. Ten to 200?μg/mL AGE2 or AGE3 alone dose-dependently inhibited the mineralization. AGE2 or AGE3 alone (200?μg/mL) significantly inhibited alkaline phosphatase (ALP) activities as well as the mineralization of the cells (p?0.01). In contrast, 22?mM glucose alone or in combination with 200?μg/mL AGE2 or AGE3 did not affect these cellular phenotypes. Real-time PCR showed that AGE2 or AGE3 alone (200?μg/mL) significantly decreased mRNA expressions of osteocalcin as well as osterix on day 14 (p?0.01). Western blot analysis showed that AGE2 or AGE3 alone (200?μg/mL) also decreased the levels of Runx2 and osterix protein expressions on days 7 and 14. AGE2 or AGE3 significantly suppressed cell growth and increased apoptotic cell death in time- and dose-dependent manners (p?0.01). Moreover, AGE3 alone (200?μg/mL) significantly increased mRNA expression of the receptor for AGEs (RAGE) on days 2 and 3 (p?0.01). These results suggest that AGE2 and AGE3, but not high glucose, may inhibit the osteoblastic differentiation of stromal cells by decreasing osterix expression and partly by increasing RAGE expression, as well as inhibiting cell growth and increasing cell apoptosis. 相似文献
85.
Yokoi A Arai H Bitoh Y Nakao M Oshima Y Nishijima E 《Journal of pediatric surgery》2012,47(6):1080-1083
PurposeCongenital tracheal stenosis is a rare condition and can be difficult to manage. One source of difficulty is postoperative tracheomalacia requiring long-term tracheal stenting. To prevent symptomatic postoperative tracheomalacia, we have been adding aortopexy to tracheal reconstruction since 2008. The aim of this study was to evaluate efficacy of aortopexy for preventing postoperative tracheomalacia after reconstruction of congenital tracheal stenosis.MethodsRetrospective chart review was conducted. From October 2003 to March 2011, 24 had tracheal reconstruction without aortopexy (group A) and 8 with aortopexy (group B). Statistical analysis was performed using Fisher's Exact test.ResultsOne had anastomotic leakage in group A, and 1, in group B (P = .44). Eleven patients required tracheostomy because of postoperative tracheomalacia confirmed by postoperative bronchoscopy in group A vs none in group B (P = .029).ConclusionsWe found that aortopexy with tracheal reconstruction reduced the need for postoperative tracheostomy in this patient group. Although there is a potential risk of anastomotic leakage because of the suspension suture on the anterior tracheal wall to aorta, we did not detect an increased incidence after aortopexy. Thus, aortic suspension may be a useful adjunct to prevent symptoms of tracheomalacia in these patients. 相似文献
86.
Yanaka K Fujita K Noguchi S Matsumaru Y Asakawa H Anno I Meguro K Nose T 《Neurologia medico-chirurgica》2003,43(10):509-12; discussion 513
The use of intraoperative angiography to monitor graft patency was retrospectively reviewed in extracranial-intracranial bypass procedures. Forty-two patients underwent 43 extracranial-intracranial bypass procedures with the use of intraoperative angiography. Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass was performed in 41 patients (42 procedures) with ischemic cerebrovascular diseases, and vertebral artery-MCA bypass using radial artery graft for intentional ligation of the common carotid artery in one patient with nasopharyngeal carcinoma. Intraoperative angiography provided high-quality subtraction images in every case. There were no complications due to angiography. Graft occlusion was observed intraoperatively in three cases, but an additional procedure reopened the occluded graft in all three cases. Graft patency rate was 100% after surgery. Outcome was excellent in 40 patients and good in one patient who underwent STA-MCA bypass. Intraoperative angiography provides useful information regarding graft patency during bypass surgery. Intraoperative assessment prior to wound closure allows for the recognition and correction of technical failure and decreases the risk of postoperative complications. 相似文献
87.
BACKGROUND: BN --> LEW small-intestine transplantation (SITx) given a 28-day course of tacrolimus results in partial tolerance and prolonged alloengraftment despite the development of indolent chronic rejection (CR). We determined whether the CR was associated with the quantity or quality of passenger leukocytes contained in the unmodified or antilymphocyte serum (ALS)-depleted BN intestine at the time of transplantation, and with the subsequent migration and persistence of these donor leukocytes in the LEW recipients (chimerism). METHODS: Four experimental cohorts were defined by differences of the BN allografts and by the infusion (or not) of na?ve donor (bone marrow cells [BMC]) on the day of the BN --> LEW SITx. All LEW recipients were treated with the same 28-day course of tacrolimus. The LEW animals received: (1) unaltered intestine; (2) intestine from ALS-treated donor; (3) intestine from ALS-treated donor plus BMC from naive BN donor on day 0; and (4) unaltered intestine and BMC from unmodified (na?ve) BN donor. RESULTS: Blood chimerism during the first 2 weeks after transplantation was lowest in the recipients of intestine from ALS-treated donors (groups 2 and 3), apparently because of the nearly complete elimination from the bowel of alphabetaTCR+ passenger leukocytes. After 2 weeks posttransplant to 5 months, greater than 2% of circulating donor cells were seen in animals given adjunct BMC from na?ve BN donors (groups 3 and 4); this was associated with the absence of CR in the intestinal allografts. With lower levels of chimerism, moderate CR including arteritis and fibrosis in the Peyer's patches and mesenteric lymph nodes was found in the intestinal grafts of all group 1 and group 2 animals. Nevertheless, the CR-prone recipients in groups 1 and 2 had equivalent weight gain for greater than or equal to 150 days as in the CR-free groups 3 and 4. Detailed tissue chimerism studies in groups 1 to 3 showed that most of the donor cells in the gut-associated lymphoid tissues were rapidly replaced, but that the residual donor constituency of up to 6% in the allografts of group 3 was nearly 10-fold greater at 150 days than in groups 1 and 2 and closely reflected the findings in blood. CONCLUSION: The development of CR in intestinal allografts to which the recipients are partially tolerant is associated with a decline with time of donor-leukocyte chimerism. Multilineage chimerism in the recipient, and a similar profile of donor cells in the allografts, is better achieved with infused donor BMC than with the normal intestinal passenger leukocytes of the intestine. The difference may be because of a higher number of precursor and pluripotent stem cells in BMC. 相似文献
88.
Protective effect of carbon monoxide inhalation for cold-preserved small intestinal grafts 总被引:9,自引:0,他引:9
Nakao A Kimizuka K Stolz DB Seda Neto J Kaizu T Choi AM Uchiyama T Zuckerbraun BS Bauer AJ Nalesnik MA Otterbein LE Geller DA Murase N 《Surgery》2003,134(2):285-292
BACKGROUND: Heme oxygenase (HO)-1 system has been shown to provide protection against oxidative stress through the degradation of heme to biliverdin, free iron, and carbon monoxide (CO). This study investigated cytoprotective efficacy of CO at a low concentration on cold ischemia/reperfusion (I/R) injury of transplanted intestine. METHODS: Lewis rat recipients of syngenic orthotopic small intestinal transplantation with 6 hours UW cold preservation were either kept in room air (air-treated control) or exposed to CO (250 ppm) for 1 hour before and 24 hours after surgery. RESULTS: In air-treated grafts, mRNA levels for interleukin-6, intracellular adhesion molecule-1, cyclooxygenase-2, and inducible nitric oxide synthase promptly increased. Sequential histopathologic analysis of untreated grafts revealed initial rapid epithelial loss, subsequent recruitment of inflammatory infiltrates, and local hemorrhage in the lamina propria, which extended downward to the epithelial crypt and muscle layer with time. CO effectively blocked proinflammatory cascade during I/R injury, inhibited upregulation of inflammatory molecules and ameliorated intestinal tissue injuries. Beneficial effects of CO were associated with improved graft blood flow without inhibiting endogenous HO-1 activity. Recipient animal survival was significantly improved with CO to 100% versus 58% in air-treated controls. CONCLUSIONS: These results indicate a significant role for CO in protecting the intestine from cold I/R injury associating with small intestinal transplantation. 相似文献
89.
PURPOSE: Long-term results of radial osteotomy for Kienb?ck's disease seldom are seen in the literature. The purpose of this study was to report the minimum 10-year results and to compare them with the 5-year results to determine whether the favorable intermediate-term results were maintained. METHODS: Twenty-five patients who underwent radial osteotomy were followed-up for a mean period of 14.5 years. They were examined for pain, grip strength, and wrist range of motion (ROM). Through a review of clinical records, 5-year postoperative results were collected. The carpal height ratio and St?hl's index were measured and the x-rays were inspected for osteoarthritic changes. We devised an original lunate grade to evaluate radiologic improvement of the ischemic lunate. Overall results were evaluated using Cooney's wrist function score and Nakamura's scoring system for Kienb?ck's disease. The long-term results were compared with both the preoperative status and the 5-year results. RESULTS: Pain, ROM, and grip strength were improved significantly after surgery, and the results were maintained for a long period. Carpal height ratio and St?hl's index did not show significant improvements but ischemic lunate showed certain radiologic improvements with time by the lunate grade system. Osteoarthritic changes were observed in 54% of patients at 5 years and in 73% of patients at the final follow-up evaluation, but the arthrosis generally was mild and did not affect the clinical results. Cooney's wrist function score was excellent or good in 96% of the patients, and the results with Nakamura's scoring system for Kienb?ck's disease were excellent or good in 68% of the patients at the final follow-up evaluation. The percentages were the same 5 years after surgery. CONCLUSIONS: Radial osteotomy for Kienb?ck's disease is a reasonable treatment option and clinical improvement lasts for a long period of time. Although radiologic improvement was not drastic, the inner structure such as sclerotic change or bone cysts of the lunate improved with time, indicating healing of the ischemic lunate. Severe osteoarthritic change or proximal migration of the capitate can be avoided. 相似文献
90.
Intracaval endovascular ultrasonography for large adrenal and retroperitoneal tumors 总被引:2,自引:0,他引:2
Kikumori T Imai T Kaneko T Sugimoto H Shibata A Hibi Y Nakao A 《Surgery》2003,134(6):989-93; discussion 993-4
BACKGROUND: An accurate diagnosis of inferior vena cava (IVC) invasion is important in deciding the surgical strategy for a large adrenal tumor. We investigated the diagnostic value of intracaval endovascular ultrasonography (ICEUS) for invasion of the IVC by a large adrenal tumor. METHODS: Nine of 163 patients with adrenal and retroperitoneal tumors underwent ICEUS between 1993 and 2002. Intravascular ultrasonography was performed through the right femoral vein with the use of an 8Fr, 20-MHz transducer. The diagnostic criterion for detecting IVC invasion with ICEUS was identification of destruction of a single echogenic layer of the IVC wall or identification of an intracaval tumor mass. The ICEUS finding was confirmed by pathologic examination. RESULTS: The mean diameter of the tumors in 9 patients undergoing ICEUS and resection was 12.6 cm (range, 8.6-16 cm). Pathologic diagnosis varied: adrenocortical carcinoma, 4; malignant pheochromocytoma, 1; leiomyosarcoma, 1; metastatic lung cancer, 1; paraganglioma, 1; and neurilemmoma, 1. Vascular invasion was identified in 2 patients by ICEUS and confirmed by examination of resected specimens. The sensitivity, specificity, and positive predictive values of ICEUS for the diagnosis of the IVC invasion were 100%, 100%, and 100%, respectively. However, these values for computed tomography were 100%, 14%, and 25%, respectively; and for cavography, 100%, 57%, and 40%, respectively. CONCLUSIONS: ICEUS provides confirmatory information regarding tumor invasion of the IVC. This modality also can assist in formulating an operative strategy for large adrenal or retroperitoneal tumors. 相似文献