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101.
Critical neuroprotective roles of heme oxygenase‐1 induction against axonal injury‐induced retinal ganglion cell death 下载免费PDF全文
Noriko Himori Kazuichi Maruyama Kotaro Yamamoto Masayuki Yasuda Morin Ryu Kazuko Omodaka Yukihiro Shiga Yuji Tanaka Toru Nakazawa 《Journal of neuroscience research》2014,92(9):1134-1142
Although axonal damage induces significant retinal ganglion cell (RGC) death, small numbers of RGCs are able to survive up to 7 days after optic nerve crush (NC) injury. To develop new treatments, we set out to identify patterns of change in the gene expression of axonal damage‐resistant RGCs. To compensate for the low density of RGCs in the retina, we performed retrograde labeling of these cells with 4Di‐10ASP in adult mice and 7 days after NC purified the RGCs with fluorescence‐activated cell sorting. Gene expression in the cells was determined with a microarray, and the expression of Ho‐1 was determined with quantitative PCR (qPCR). Changes in protein expression were assessed with immunohistochemistry and immunoblotting. Additionally, the density of Fluoro‐gold‐labeled RGCs was counted in retinas from mice pretreated with CoPP, a potent HO‐1 inducer. The microarray and qPCR analyses showed increased expression of Ho‐1 in the post‐NC RGCs. Immunohistochemistry also showed that HO‐1‐positive cells were present in the ganglion cell layer (GCL), and cell counting showed that the proportion of HO‐1‐positive cells in the GCL rose significantly after NC. Seven days after NC, the number of RGCs in the CoPP‐treated mice was significantly higher than in the control mice. Combined pretreatment with SnPP, an HO‐1 inhibitor, suppressed the neuroprotective effect of CoPP. These results reflect changes in HO‐1 activity to RGCs that are a key part of RGC survival. Upregulation of HO‐1 signaling may therefore be a novel therapeutic strategy for glaucoma. © 2014 Wiley Periodicals, Inc. 相似文献
102.
Kiyoshi Nakazawa Tsuneharu Sakurai Akihiko Takagi Ryoji Kishi Keizo Osada Toshihiko Nanke Fumihiko Miyake Naoki Matsumoto Shinichi Kobayashi 《Circulation journal》2003,67(6):511-514
The autonomic properties in 27 patients with the electrocardiographic morphology of Brugada syndrome were investigated using 24-h Holter monitoring: 10 patients had a history of ventricular fibrillation (VF; Br-VF group) and 17 did not (Br-N group); there were 26 healthy subjects enrolled in this study. All subjects underwent normal Holter data monitoring and power spectral analysis. Few extrasystoles were observed in either group, and the mean heart rate (HR), maximum HR, and total heart beats over 24 h were obtained. All of these measurements were significantly lower in the Br-VF group than in the Br-N and healthy subject groups. The RR interval variability was analyzed over 512 beats every 10 min. The high-frequency component (0.15-0.40 Hz; HF), low-frequency component (0.04-0.15 Hz; LF) and the LF/HF ratio were analyzed over 24 h. The HF was significantly higher and LF/HF ratio lower in the Br-VF group than in the healthy subjects. The HF was also significantly higher than in the Br-N group. During the night (00.00-05.00 h), the HF was significantly higher in the Br-VF group, and the LH/HF lower. During the day (12.00-17.00 h), the HF was significantly higher in the Br-VF group, but there was no difference in the LF/HF. These results indicate that high vagal tone and low sympathetic tone are specific properties of symptomatic Brugada syndrome. 相似文献
103.
Hisato Nakazawa Masataka Komori Yuta Shibamoto Takahiko Tsugawa Yoshimasa Mori Tatsuya Kobayashi 《Acta neurochirurgica》2014,156(8):1483-1489
Background
The treatment planning for Gamma Knife (GK) stereotactic radiosurgery (SRS) that performs dose calculations based on tissue maximum ratio (TMR) algorithm has disadvantages in predicting dose in tissue heterogeneity. The latest version of the planning software is equipped with a convolution dose algorithm as an optional extra and the new algorithm is able to compensate for head inhomogeneity. However, the effect of this improved calculation method requires detailed validation in clinical cases. In this study, we compared absolute and relative dose distributions of treatment plans for acoustic neurinoma between TMR and the convolution calculation.Methods
Twenty-nine clinically used plans created by TMR algorithm were recalculated by convolution method. Differences between TMR and convolution were evaluated in terms of absolute dose (beam-on time), dosimetric parameters including target coverage, selectivity, conformity index, gradient index, radical homogeneity index and the dose-volume relationship.Results
The discrepancy in estimated absolute dose to the target ranged from 1 to 7 % between TMR and convolution. In addition, dosimetric parameters of the two methods achieved statistical significance. However, it was difficult to see the change of relative dose distribution by visual assessment on a monitor.Conclusions
Convolution, heterogeneity correction calculation, and the algorithm are necessary to reduce the dosimetric uncertainty of each case in GK SRS. 相似文献104.
105.
Nakazawa Yujiro Tamura Fumiyo Genkai Sae Shindo Hiroki Isoda Tomoko Mizukami Miki Kikutani Takeshi 《Odontology / the Society of the Nippon Dental University》2019,107(3):368-373
Odontology - This study aimed to determine the significance of oral ingestion in tube-fed adults. Six males and three females (mean age 48.1 ± 12.4 years) with severe... 相似文献
106.
Kanae Hirabayashi Yozo Nakazawa Hiroki Matsuura Yosuke Hara Takashi Kurata Koichi Hirabayashi Shoji Saito Kentaro Yoshikawa Miyuki Tanaka Ryu Yanagisawa Kazuo Sakashita Kenichi Koike 《International journal of hematology》2014,99(4):477-486
Long-term surviving recipients of allogeneic hematopoietic stem cell transplantation (HSCT) often suffer from diabetes mellitus (DM). We sought to identify risk factors for the development of post-transplant DM and impaired glucose tolerance (IGT) in pediatric HSCT patients. Glucose tolerance statuses were evaluated in 22 patients aged 6.3–21.8 years who had received allogeneic HSCT between the ages of 0.8–13.5 years. Five patients were diagnosed as having type 2 DM, and treated with insulin or oral hypoglycemic agents. Five patients were included in the IGT group, and the remaining 12 children were in the normal glucose tolerance (NGT) group. The cumulative incidence of DM plus IGT was 11.6 % at 5 years and 69.3 % at 10 years. None of the patients were obese/overweight and none had a family history of DM. There were no significant differences in serum levels of leptin and adiponectin between the DM + IGT and the NGT groups. An average preprandial glucose levels in the DM + IGT group were significantly higher than those in the NGT group from preparative conditioning to 60 days after HSCT. In multivariate analysis, an age of ≥6 years at the time of HSCT was significantly associated with the development of DM + IGT. Additionally, careful follow-up is necessary, even for NGT patients. 相似文献
107.
Hajime Uchida Seisuke Sakamoto Masatoshi Matsunami Kengo Sasaki Takanobu Shigeta Hiroyuki Kanazawa Akinari Fukuda Atsuko Nakazawa Osamu Miyazaki Shunsuke Nosaka Mureo Kasahara 《Pediatric transplantation》2014,18(7):E232-E235
CACS is rare, although it has been reported to be a potential risk factor for hepatic artery thrombosis following LT. We herein present the case of a 14‐yr‐old male with stenosis of the origin of the celiac trunk. Preoperative CT and color ultrasonography showed narrowing of the proximal celiac artery. The patient underwent DDLT with standard arterial reconstruction without dividing the gastroduodenal artery. His postoperative course was uneventful, with an excellent hepatic artery flow on Doppler ultrasonography. Applying a meticulous preoperative evaluation and the appropriate surgical technique is crucial in patients with CACS. 相似文献
108.
E. Kodama K. Morita H. Maeda J. Nakamura S. Kinoshita N. Kawamura Y. Nakazawa 《Human psychopharmacology》1996,11(2):123-130
The goal of the present study was to evaluate the effects of acute nicotine administration following 18 h of abstinence from cigarette smoking. Event-related potentials (ERPs) were measured in 13 male volunteers for five successive sessions. The peak amplitude and the area of the P300 significantly increased during acute withdrawal. An increase in P300 values also was observed following resumption of smoking. However, in subjects pretreated with nicotine gum, no increase in P300 values was observed following resumption of smoking. The increase in P300 values persisted for several weeks and returned to control values following 1 month of routine daily smoking. The P300 amplitude was negatively correlated with the daily dose of nicotine. These results suggest that attention and/or arousal may be enhanced by the withdrawal and the resumption of smoking. The mechanisms involved in CNS hypersensitivity to motivate the subject to smoke may persist in the presence of an increased P300 value, even following resumption of routine daily smoking. 相似文献
109.
IgG4-related sclerosing cholangitis (IgG4-SC) can be classified into four types based on cholangiographic findings and regions of biliary stricture. This cholangiographic classification is useful to differentiate IgG4-SC from mimickers including cholangiocarcinoma, primary sclerosing cholangitis, and pancreatic cancer. Autoimmune pancreatitis (AIP) is a valuable clue for the diagnosis of IgG4-SC because the two are frequently found in association with each other. Two sets of diagnostic criteria for IgG4-SC have been proposed. In Japan, the clinical diagnostic criteria 2020 were recently developed. These clinical diagnostic criteria include narrowing of the intrahepatic and/or extrahepatic bile duct, thickening of the bile duct wall, serological findings, pathological findings, other organ involvement, and effectiveness of steroid therapy. When these criteria are applied, IgG4-SC is initially classified as associated or not associated with AIP, and cholangiographic classification is used for differential diagnosis. In most instances, IgG4-SC can be diagnosed on the basis of clinical diagnostic criteria. However, it is challenging to diagnose isolated IgG4-SC or IgG4-SC not associated with AIP. Here, we review the classification and diagnostic criteria for IgG4-SC, specifically focusing on the clinical diagnostic criteria 2020 and a large IgG4-SC case series from a nationwide survey in Japan. 相似文献
110.
Matsukawa N Ikenaka K Nanmoku K Yuasa H Hattori M Kawano M Nakazawa H Fujimori O Ueda R Ojika K 《Developmental neuroscience》2003,25(5):349-356
Hippocampal cholinergic neurostimulating peptide precursor protein (HCNP-pp) is a unique multifunctional protein, being not only the precursor of HCNP, which promotes the phenotype development of septo-hippocampal cholinergic neurons, but also the binding protein of phosphatidylethanolamine, ATP, Raf-1 kinase (known as "Raf-1 kinase inhibitory factor" in peripheral organs), and serine protease. We obtained a high-titer retroviral vector harboring HCNP-pp cDNA by the use of a modified packaging cell line and centrifugation, and by injecting it into embryonic mouse ventricles, we investigated the function of its gene product within the central nervous system (CNS). We found that efficient transduction into hippocampal pyramidal neurons can be achieved by injecting the vector into embryonic brain ventricles on embryonic day 14 (E14). Three days after receiving the intraventricular injection of the high-titer HCNP-pp retrovirus vector on E14, the tissues around the ventricles showed an overexpression of HCNP-pp. This was accompanied by a reduced amount of activated MEK and Erk (as analyzed by histochemical and Western blot methods), suggesting that HCNP-pp also regulates the MAP-kinase cascade within the CNS. Surprisingly, mouse brains that received the HCNP-pp retroviral vector showed massive malformation of the hippocampus and cerebellum when examined 30 days after birth. This shows that strictly regulated HCNP-pp gene expression is necessary for the normal development of the mouse brain, and that the moderate overexpression achieved by retroviral vector-mediated gene transfer is sufficient to cause severe abnormality of entire brain structures. 相似文献