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101.
Electroconvulsive shock increases preproenkephalin messenger RNA abundance in rat hypothalamus. 总被引:1,自引:2,他引:1 下载免费PDF全文
K Yoshikawa J S Hong S L Sabol 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(2):589-593
Daily administration of electroconvulsive shock (ECS) to rats for 10 days increased the content of [Met5]enkephalin in the hypothalamus and the striatum by 64% and 45%, respectively. The effect of ECS on the relative abundance of mRNA coding for the enkephalin precursor preproenkephalin was investigated. Analysis by cell-free translation of polyadenylylated RNA and immunoprecipitation of preproenkephalin revealed ECS-elicited increases of 79% and 14% in preproenkephalin mRNA activity in the hypothalamus and striatum, respectively. ECS treatment did not affect the general translational activity of total polyadenylylated RNA from these brain regions. A 32P-labeled probe prepared from a rat preproenkephalin cDNA clone hybridized with an apparently single species of polyadenylylated RNA of approximately equal to 1450 nucleotides from both hypothalamus and striatum. Dot-blot hybridization of polyadenylylated RNA with the rat probe indicated that ECS elicits a 76% increase in the preproenkephalin mRNA abundance in the hypothalamus and no significant change in the striatum. These results suggest that ECS treatment leads to enhanced biosynthesis of the enkephalin precursor in hypothalamic neurons. 相似文献
102.
A novel Na+‐Independent alanine‐serine‐cysteine transporter 1 inhibitor inhibits both influx and efflux of D‐Serine 下载免费PDF全文
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
103.
Sato H Shimada M Kurita N Iwata T Nishioka M Morimoto S Yoshikawa K Miyatani T Goto M Kashihara H Takasu C 《Surgical endoscopy》2012,26(8):2240-2246
Background
Laparoscopy-assisted gastrectomy (LAG) is becoming widely used for early gastric cancer. However, how the curability and long-term prognosis of LAG and open gastrectomy (OG) for early and advanced gastric cancer compare remains unclear. This study assessed short- and long-term outcomes after LAG with lymph node dissection in early and advanced gastric cancer.Methods
A total of 332 patients who underwent LAG or OG for early and advanced gastric cancer from January 2001 through December 2010 were reviewed retrospectively. The mean operating time, estimated mean blood loss, number of dissected lymph nodes, and survival rates were compared between LAG and OG for early and advanced gastric cancer.Results
Overall, 47.6% (158/332) of patients underwent LAG; D1, D1+ lymph node dissection was carried out in 77.2%, with D2 dissection in 22.8%. Only one patient required conversion to OG. Comparing LAG and OG with D1, D1+ lymph node dissection for early gastric cancer (EGC), mean operating time was significantly longer, estimated mean blood loss was significantly smaller, and the average number of retrieved lymph nodes was significantly greater with LAG. The rate of specific postoperative morbidity was 17.2% for LAG patients and 25.0% for OG patients, with no postoperative mortality. Survival and recurrence rates were not significantly different. Comparing LAG and OG with D2 lymph node dissection for advanced gastric cancer (AGC), mean operating time was significantly longer and estimated mean blood loss was significantly smaller with LAG, while the average number of retrieved lymph nodes, specific postoperative morbidity and mortality, and survival and recurrence rates were not significantly different.Conclusions
LAG with D1, D1+ lymph node dissection for EGC is safe and equivalent to open gastrectomy in curability. Moreover, LAG with D2 lymph node dissection for AGC is comparable to OG with D2 lymph node dissection with regard to short- and long-term results. 相似文献104.
Comparison of grey matter and metabolic reductions in frontotemporal dementia using FDG-PET and voxel-based morphometric MR studies 总被引:1,自引:0,他引:1
Kanda T Ishii K Uemura T Miyamoto N Yoshikawa T Kono AK Mori E 《European journal of nuclear medicine and molecular imaging》2008,35(12):2227-2234
Purpose The aim of this study was to investigate the regional differences between the morphologic and functional changes in the same
patients with frontotemporal dementia (FTD) using statistical parametric mapping and voxel-based morphometry (VBM).
Methods Thirteen FTD patients (mean age, 64.9 years old; mean MMSE score, 17.7), 20 sex-matched Alzheimer’s disease (AD) patients
(mean age, 65.0 years old; mean MMSE score, 17.5), and 20 normal volunteers (mean age, 65.2 years old; mean MMSE score, 29.0)
underwent both [18F]FDG positron emission tomography and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used
to conduct a VBM analysis of the morphologic data, which were compared voxel by voxel with the results of a similar analysis
of glucose metabolic data.
Results FTD patients showed decreased grey matter volume and decreased glucose metabolism in the frontal lobe and anterior temporal
lobe. In addition, there was a clear asymmetry in grey matter volume in FTD patients by the VBM analysis while the glucose
metabolic data showed little asymmetry. In AD patients, glucose metabolic reduction occurred in the bilateral posterior cingulate
gyri and parietal lobules while grey matter density decreased the least in the same patients.
Conclusion In FTD, metabolic and morphologic changes occur in the bilateral frontal lobe and temporal lobe with a limited asymmetry whereas
there was considerable discordance in the AD group. 相似文献
105.
Yoshikawa T Aoki S Abe O Hayashi N Masutani Y Masumoto T Mori H Satake Y Ohtomo K 《Radiation Medicine》2008,26(8):481-487
Purpose The aim of the study was to estimate the effect of distortion correction with correspondence to numbers of encoding directions
to acquire diffusion tensor imaging (DTI) of improved quality.
Materials and methods Ten volunteers underwent DTI of the head using echo planar imaging with 6, 13, 27, and 55 encoding directions. Fractional
anisotropy (FA) maps and apparent diffusion coefficient (ADC) maps were created before and after distortion correction. Regions
of interest were placed in the corpus callosum on each map, and standard deviations of FA and ADC were calculated. FA maps
were also evaluated visually by experienced neuroradiologists.
Results Dispersion of standard deviations tended to be reduced after distortion correction, with significant differences found in
FA maps with 6 encoding directions, ADC maps with 6 directions, and ADC maps with 13 directions (P < 0.001, P < 0.005, and P < 0.05, respectively). Visual image quality was improved after distortion correction (P < 0.01 for all of the visual comparisons).
Conclusion Distortion correction is effective in providing DTI of enhanced quality, notwithstanding the number of encoding directions.
This article was presented at a Japan Radiological Society meeting in 2002 相似文献
106.
Ishii K Kanda T Harada A Miyamoto N Kawaguchi T Shimada K Ohkawa S Uemura T Yoshikawa T Mori E 《European radiology》2008,18(11):2678-2683
The utility of measuring the corpus callosal angle (CA) for the diagnosis of idiopathic normal pressure hydrocephalus (INPH)
was investigated. Three-dimensional magnetic resonance imaging (MRI) was performed in 34 INPH patients, 34 Alzheimer’s disease
(AD) patients, and 34 normal control (NC) subjects. Measurement of the CA on the coronal MR images of the posterior commissure
perpendicular to the anteroposterior commissure plane was performed for all subjects. The CA of the INPH group (mean ± SD,
66 ± 14°) was significantly smaller than those of the AD (104 ± 15°) and NC (112 ± 11°) groups. When using the threshold of
the mean − 2SD value of the NC group (= 90°), an accuracy of 93%, sensitivity of 97%, and specificity of 88% were observed
for discrimination of INPH from AD patients. Measuring the CA helps in differentiating INPH patients from AD and normally
aged subjects. 相似文献
107.
Miyazaki S Murase K Yoshikawa T Morimoto S Ohno Y Sugimura K 《The British journal of radiology》2008,81(970):790-800
The purpose of this study was to investigate the accuracy of a quantitative method for estimating arterial hepatic blood flow and portal hepatic blood flow separately using a dual-input single-compartment model compared with the maximum slope method using computer simulations and clinical data. In computer simulations, the rate constants for the transfer of contrast agent (CA) from the hepatic artery to the liver (K(1a)), from the portal vein to the liver (K(1p)) and from the liver to the blood (k(2)) were estimated from simulated time-density curves with various transit times of CA from the aorta to the liver (tau(a)) and from the portal vein to the liver (tau(p)) using the linear least-squares (LLSQ) method. In clinical studies, dynamic CT data were acquired from 27 patients, and parametric maps of K(1a), K(1p) and k(2) were generated by applying the LLSQ method pixel by pixel. In simulation studies, tau(a) and tau(p) were found to have a large and a small effect on the estimates of K(1a) and K(1p), respectively. In clinical studies, the K(1a) and K(1p) values estimated with the maximum slope method were underestimated by 60+/-29% and 37+/-12%, respectively, compared with those estimated by the LLSQ method. In conclusion, our results suggest that correction of tau(a) is necessary for accurately estimating K(1a) and K(1p). Our method is therefore promising for the evaluation of hepatic blood flow in various liver diseases because it allows us to evaluate arterial hepatic blood flow and portal hepatic blood flow separately and visually. 相似文献
108.
Maruyama K Iijima K Ikeda M Kitamura A Tsukaguchi H Yoshiya K Hoshii S Wada N Uemura O Satomura K Honda M Yoshikawa N 《Pediatric nephrology (Berlin, Germany)》2003,18(5):412-416
Podocin is an integral membrane protein encoded by NPHS2, which is mapped to 1q25-31 and is exclusively expressed in glomerular podocytes. NPHS2 mutations are responsible for autosomal recessive familial steroid-resistant nephrotic syndrome (SRNS) with minor glomerular abnormalities or focal segmental glomerulosclerosis (FSGS), which is characterized by early childhood onset (age less than 6 years) and rapid progression to chronic renal insufficiency. This gene mutation is also responsible for an adolescent/adult onset form of autosomal recessive familial FSGS with heavy proteinuria. It has been demonstrated that sporadic SRNS and heavy proteinuria are also due to NPHS2 gene mutations. We isolated genomic DNA from 36 Japanese children with chronic renal insufficiency caused by SRNS or heavy proteinuria, and analyzed all eight exons and exon-intron boundaries of NPHS2 using the polymerase chain reaction and direct sequencing. The age at onset of disease was 3.9+/-0.5 years. There were 29 patients with SRNS and 7 with heavy proteinuria without nephrotic syndrome at the onset, but all patients developed chronic renal insufficiency 4.6+/-0.8 years after the onset. A new homozygous missense variant of NPHS2, G34E (G101A) in exon 1, was detected in 1 of 36 patients. However, this homozygous variant was also found in 1 of 44 normal controls, suggesting that the mutation is a polymorphism. Two silent variants (T954C and A1038G) in exon 8 of this gene were also identified in some of the patients and normal controls, indicating that the silent variants are also polymorphisms. There was no significant difference in the genotypic and allelic frequencies of T954C and A1038G polymorphisms between the patients and normal controls. In conclusion, NPHS2 gene mutations are not a major cause of chronic renal insufficiency caused by sporadic SRNS or heavy proteinuria in Japanese children. 相似文献
109.
Renal involvement in children with influenza A virus infection 总被引:2,自引:0,他引:2
Watanabe T Yoshikawa H Abe Y Yamazaki S Uehara Y Abe T 《Pediatric nephrology (Berlin, Germany)》2003,18(6):541-544
Renal involvement in influenza A virus infection has been rarely reported. To define the clinical characteristics and the factors contributing to the development of renal involvement in influenza A virus infection, we reviewed the clinical characteristics, laboratory data, pediatric risk of mortality (PRISM) score, and the number of systemic inflammatory response syndrome (SIRS) criteria and dysfunctional organs in 45 hospitalized children with influenza A virus infection. Eleven (24.4%) patients had renal involvement. All patients with renal involvement suffered from sepsis and multiple organ dysfunction syndrome (MODS) and 5 developed acute renal failure (ARF). The incidences of dehydration, hypotension, disseminated intravascular coagulation (DIC), and rhabdomyolysis were significantly higher in patients with renal involvement. PRISM scores, the numbers of SIRS criteria and dysfunctional organs, and mortality rate were also higher in patients with renal involvement. Influenza A RNA was absent in the renal tissues of 3 patients with ARF. These results suggested that renal involvement in influenza A virus infection occurred in patients with sepsis and MODS; dehydration, hypotension, DIC, and rhabdomyolysis were factors contributing to its development; direct viral injury to the kidney did not seem to occur in influenza A virus infection. 相似文献
110.
Keiichiro Oura Hisao Moritomo Toshiyuki Kataoka Kunihiro Oka Tsuyoshi Murase Kazuomi Sugamoto Hideki Yoshikawa 《Journal of orthopaedic science》2017,22(1):50-55