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排序方式: 共有926条查询结果,搜索用时 15 毫秒
1.
Takafumi Nagaoka Yoichi Katayama Toshikazu Kano Kazutaka Kobayashi Hideki Oshima Chikashi Fukaya Takamitsu Yamamoto 《Neuromodulation》2007,10(3):206-215
Objective. Employing [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess the correlation between the effect of deep brain stimulation (DBS) on the subthalamic nucleus (STN) and the regional cerebral metabolic rate of glucose (rCMRGlc) in advanced Parkinson's disease patients (N = 8). Materials and Methods. On the basis of patients’ diary records, we performed FDG‐PET during the off‐period of motor activity with on‐ or off‐stimulation by STN‐DBS on separate days and analyzed the correlation between changes in motor symptoms and alterations in the rCMRGlc. Result. When FDG‐PET was performed, the motor score on the unified Parkinson's disease rating scale (UPDRS) was 64% lower with on‐stimulation than with off‐stimulation (p < 0.001, Wilcoxon single‐rank test). STN‐DBS increased the rCMRGlc in the posterior part of the right middle frontal gyrus, which corresponded to the premotor area, and the right anterior lobe of the cerebellum (p < 0.005, paired t‐test). No region exhibited a decrease in rCMRGlc. Among the items of the UPDRS motor score, the changes in resting tremor and rigidity of the left extremities showed a significant correlation with the changes in rCMRGlc observed in the right premotor area (p < 0.02 and p < 0.05, respectively, Spearman's rank correlation). Conclusions. STN‐DBS either activates the premotor area or normalizes the deactivation of the premotor area. These FDG‐PET findings obtained are consistent with the idea that STN‐DBS modifies the activities of neural circuits involved in motor control. 相似文献
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Hidai C Kawana M Habu K Kazama H Kawase Y Iwata T Suzuki H Quertermous T Kokubun S 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,287(2):1165-1175
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery. 相似文献
4.
Tanaka T Nakanishi T Hasuike Y Inoue T Noguchi K Takamitsu Y 《Nihon Jinzo Gakkai shi》1999,41(8):754-763
Whether L-Arginine (L-ARG) ameliorates or aggravates renal function and histopathological changes in several models of renal disease remains controversial as L-ARG is the substrate for nitric oxide (NO) synthase as well as the precursor of proline and polyamines which cause renal fibrosis. These ambiguous results might be attributed to differences in the dose and period of L-ARG administration and the animal model used in each observation. Therefore, we tested the dose-dependent effect of L-ARG on mean blood pressure (MBP), 24-hour urinary excretion of protein (UP), NO metabolites (NO2(-) + NO3-) and cyclic GMP (cGMP), plasma asymmetrical dimethylarginine (ADMA), glomerular sclerosis index (SI) and % interstitial fibrosis area (%INT) in 5/6 nephrectomized SD rats. These 5/6 nephrectomized SD rats were divided into 4 groups: 1. L-ARG 0.2 g/kg/day (0.2 g ARG), 2. L-ARG 1 g/kg/day (1 g ARG), 3. L-ARG 2 g/kg/day (2 g ARG), 4. No administration of L-ARG(ARG(-)). Compared with ARG(-)MBP, UP and ADMA were significantly decreased and NO2(-) + NO3-, cGMP were significantly increased in the 0.2 g ARG. SI group and %INT were significantly increased in the 2 g ARG group and decreased in the 0.2 g ARG group. A small dose of L-ARG ameliorated glomerulosclerosis and interstitial fibrosis while a larger dose did not. SI, %INT and ADMA were inversely correlated with NO2(-) + NO3-. These data suggested that renal NO synthesis might attenuate glomerulosclerosis and interstitial fibrosis and the rise in ADMA and L-ARG might cause the decrease in NO. 相似文献
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Kohei Fukuoka Atsushi Sasaki Takaaki Yanagisawa Tomonari Suzuki Kenji Wakiya Jun-ichi Adachi Kazuhiko Mishima Takamitsu Fujimaki Masao Matsutani Ryo Nishikawa 《Brain tumor pathology》2012,29(4):229-234
We report a case of pineal parenchymal tumor (PPT) in an 11-year-old girl. Brain magnetic resonance imaging (MRI) revealed a large tumor (48?mm) located in the pineal region with heterogeneous enhancement after gadolinium administration. The patient underwent tumor removal with craniotomy; only partial tumor resection could be performed because of massive intratumoral bleeding. Histopathological examination of the tumor showed lobular proliferation of round cells with moderate atypia. Cellularity varied by area, and focal Homer Wright rosettes were identified. Examination of tumor cells revealed a few mitoses (two mitotic figures per 10 high-powered fields), and immunohistochemical staining revealed positivity for synaptophysin, slight positivity for neurofilament protein (NFP) with antibody clone 2F11, and strong positivity for NFP with clone NF-M+H. The pathological diagnosis was pineal parenchymal tumor of intermediate differentiation grade II according to World Health Organization criteria despite a high (22%) MIB-1 labeling index (LI). The patient had a favorable clinical course after an intensified chemotherapy regimen designed for pineoblastoma and radiotherapy administered to the entire neuraxis, followed by stereotactic radiotherapy. In conclusion, MIB-1 LI could be a useful tool for deciding therapeutic strategies for PPT treatment when there is a discrepancy between clinical findings and pathological grading. 相似文献
6.
Wang W Yuasa T Tsuchiya N Maita S Kumazawa T Inoue T Saito M Ma Z Obara T Tsuruta H Satoh S Habuchi T 《Endocrine-related cancer》2008,15(4):943-952
Androgen-deprivation therapy (ADT) of patients with prostate cancer (PCa) is known to reduce bone mineral density (BMD). However, the most studies examined Caucasian or black patients and the effects of ADT on the bone metabolism of East Asians are unclear. Therefore, we performed a cross-sectional study to elucidate the influence of ADT on bone metabolism in Japanese patients. In total, 101 native Japanese patients with PCa were enrolled. They consisted of 58 ADT-treated and 43 hormone-naive patients. The BMD in the lumbar spine, total hip, and femoral neck was measured by dual energy X-ray absorptiometry and expressed in s.d. units relative to young adult men (T-score) or age-matched men (Z-score). Serum levels of bone metabolism markers were also measured. The BMDs at the three sites revealed that 2.3% (1/43) and 8.6% (5/58) of the hormone-naive and ADT-treated PCa patients had osteoporosis respectively, but this difference failed to achieve statistical significance (P=0.294). The two groups also did not differ significantly in their Z-scores of the three sites, and univariate and multivariate analyses indicated that ADT was not a significant risk factor for decreased BMD. In addition, a significant correlation between the duration of ADT and BMD was not observed for all three sites measured. However, the ADT-treated patients had significantly higher serum levels of N-terminal telopeptide of type I collagen (NTx) than the hormone-naive patients (P=0.017). To our knowledge, this is the first study to demonstrate the low prevalence of osteoporosis in both ADT-treated and hormone-naive Japanese PCa patients. Moreover, ADT did not significantly increase the prevalence of osteoporosis in this Japanese population. 相似文献
7.
BACKGROUND/AIMS: The E-cadherin-mediated cell adhesion system is now considered to be an "invasion suppressor system" in cancer cells. The purpose of this study is to examine the effect of E-cadherin on morphogenesis of MKN28 human gastric carcinoma cell line in the course of E-cadherin antisense S-oligodeoxynucleotide (ODN) treatment. METHODOLOGY: The effect of E-cadherin antisense or random S-ODN treatment on cell growth, morphology in monolayer culture, and E-cadherin protein expression of MKN28 cells were evaluated. Further, immunohistochemical examination was performed. RESULTS: Cell growth under 3-microM and 6-microM E-cadherin antisense S-ODN treatment did not differ from that under random S-ODN treatment. Although the expression of E-cadherin was decreased assuredly at the time of 6 days after 3-microM E-cadherin antisense S-ODN treatment by immunohistochemical examination, cell-cell adhesion was still observed until Day 10 after the treatment. On Day 15, the cells lost the cell-cell adhesion and showed the detachment and intercellular slits at least. Expression of the insoluble fraction of E-cadherin protein decreased in E-cadherin antisense S-ODN treatment cells at 6 days. CONCLUSIONS: In this study, we demonstrated that discrepancy between E-cadherin protein expression and morphology exists in MKN28 cells treated with E-cadherin antisense S-ODN treatment. 相似文献
8.
Dayton D. McMillan Junko Maeda Justin J. Bell Matthew D. Genet Garrett Phoonswadi Kelly A. Mann Susan L. Kraft Hisashi Kitamura Akira Fujimori Yukie Yoshii Takako Furukawa Yasuhisa Fujibayashi Takamitsu A. Kato 《Journal of radiation research》2015,56(5):784-791
Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a 64Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of 64Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from 64Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to 64Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D10 values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that 64Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from 64Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after 64Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that 64Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of 64Cu-ATSM as a cancer treatment modality for hypoxic tumors. 相似文献
9.
Takamitsu Hattori Darson Lai Irina S. Dementieva Sherwin P. Monta?o Kohei Kurosawa Yupeng Zheng Louesa R. Akin Kalina M. ?wist-Rosowska Adrian T. Grzybowski Akiko Koide Krzysztof Krajewski Brian D. Strahl Neil L. Kelleher Alexander J. Ruthenburg Shohei Koide 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(8):2092-2097
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