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911.
912.
Towart LA Alves SE Znamensky V Hayashi S McEwen BS Milner TA 《The Journal of comparative neurology》2003,463(4):390-401
Cholinergic septohippocampal neurons are affected by circulating estrogens. Previously, we found that extranuclear estrogen receptor-alpha (ERalpha) immunoreactivity in presynaptic profiles had an overlapping distribution with cholinergic afferents in the rat hippocampal formation. To determine the subcellular relationships between cholinergic presynaptic profiles and ERalpha, hippocampal sections were dually immunolabeled for vesicular acetylcholine transporter (VAChT) and ERalpha and examined by electron microscopy. Within the hippocampal formation, immunoreactivities for VAChT and ERalpha both were presynaptic, although their subcellular targeting was distinct. VAChT immunoreactivity was found exclusively within presynaptic profiles and was associated with small synaptic vesicles, which usually filled axon terminals. VAChT-labeled presynaptic profiles were most concentrated in stratum oriens of the hippocampal CA1 region and dentate inner molecular layer and hilus. In contrast, ERalpha immunoreactivity was found in clusters affiliated either with select vesicles or with the plasmalemma within preterminal axons and axon terminals. ERalpha-immunoreactive (IR) presynaptic profiles were more evenly distributed between hippocampal lamina than VAChT-IR profiles. Quantitative ultrastructural analysis revealed that VAChT-IR presynaptic profiles contained ERalpha immunoreactivity (ranging from 3% to 17%, depending on the lamina). Additionally, VAChT-IR presynaptic profiles apposed ERalpha-IR dendritic spines, presynaptic profiles, and glial profiles; many of the latter two types of profiles abutted unlabeled dendritic spines that received asymmetric (excitatory-type) synapses from unlabeled terminals. The presence of ERalpha immunoreactivity in cholinergic terminals suggests that estrogen could rapidly and directly affect the local release and/or uptake of acetylcholine. The affiliation of cholinergic terminals with excitatory terminals near ERalpha-labeled dendritic spines or glial profiles suggests that alterations in acetylcholine release could indirectly affect estrogen-modulated structural plasticity. 相似文献
913.
Association of phosphorylation site of tau protein with neuronal apoptosis in Alzheimer's disease 总被引:4,自引:0,他引:4
Kobayashi K Nakano H Hayashi M Shimazaki M Fukutani Y Sasaki K Sugimori K Koshino Y 《Journal of the neurological sciences》2003,208(1-2):17-24
In addition to neuritic changes and amyloid deposits, neuronal and glial cell apoptosis is an important pathological feature of Alzheimer's disease (AD). Several factors have been postulated as causes or triggers of cellular apoptotic change. This study focused on a quantifiable relationship between phosphorylation sites of tau protein in the neurofibrillary tangles (NFT) and neuronal apoptosis. Five monoclonal anti-tau antibodies (AT180, AT8, HT7, Tau2 and Tau5) for NFT labeling and TdT-mediated UTP nick-end labeling (TUNEL) for localizing apoptotic change were employed. TUNEL-stained neuronal nuclei showed significantly high density in the entorhinal cortex, cornu ammonis (CA) and the parietal cortex. In all regions, density of TUNEL-stained neuronal nuclei showed significantly direct correlation with that of AT8-, AT180- and Tau2-positive neurons. Correlation of TUNEL-stained neuronal nuclei with tau-positive neurons differed depending on the cerebral regions. Density of TUNEL-stained neuronal nuclei showed inverse correlation with that of both AT8-positive and Gallyas-stained NFT in the CA and showed significantly direct correlation with AT8- and HT7-positive neurons in the frontal cortex. Density of tau-positive and Gallyas-stained NFT was higher than that of TUNEL-stained nuclei. We conclude that phosphorylation sites of tau, 159-163 and 202-205, are probably associated with neuronal apoptosis and apoptotic change follows abnormal phosphorylation of tau. 相似文献
914.
915.
916.
Yoshida S Kamiyama T Nio M Ohi R Hayashi Y Sano N Endo N 《No to hattatsu. Brain and development》2003,35(3):211-214
We present here the indication, procedure and results of surgical treatment of gastroesophageal reflux (GER) for neurologically impaired children. We decide its indication based on clinical symptoms and findings of upper GI series, esophageal pH monitoring and GI fiberscopy, respecting the QOL of the patient and family. Laparoscopic fundoplication has become the first choice in surgical treatment of GER because of its good results. However, an anti-reflux procedure is not effective in patients with intractable aspiration. A laryngotracheal separation procedure should be applied for these cases. 相似文献
917.
Hayashi T Ito J Taira S Katsura K Shingaki S Hoshina H 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2003,96(1):112-117
OBJECTIVE: We sought to assess the reliability of repeated sonography in the detection of cervical lymph node metastases at the earliest stage during a follow-up period in patients with stage I or stage II carcinoma of the tongue. STUDY DESIGN: Eighteen consecutive patients with stage I or II squamous cell carcinoma of the tongue were included. When possible, every patient was examined with sonography approximately every 2 weeks during the follow-up period. RESULTS: With repeated sonography on 18 patients, 7 metastatic nodes of 7 patients (39%) meeting our criteria were found. With the use of computed tomography, we diagnosed 10 nodes (including the 7 nodes observed with sonography) in these 7 patients as metastatic. A histopathologic examination revealed that 12 nodes in the same 7 patients had metastatic foci. For sonography, the sensitivity per node was 58%, whereas that of computed tomography was 83%. CONCLUSIONS: Follow-up sonography enabled the detection of all patients who had subsequent subclinical lymph node metastases. However, the sensitivity of sonography in the detection of smaller metastatic nodes was lower than that of computed tomography. 相似文献
918.
Three-dimensional analysis of dental casts based on a newly defined palatal reference plane 总被引:1,自引:0,他引:1
The purpose of this study was to establish a new method for orthodontic diagnosis that integrates the three-dimensional (3-D) shape of a dental cast and the craniofacial morphology using a newly defined palatal reference plane. We also measured the accuracy of this new palatal reference plane as a reference for measurement and its spatial relationship to the framework of the craniofacial skeleton using lateral and frontal cephalometric radiography and maxillary dental casts, which were transferred using an anatomical face-bow. Eighteen female subjects were included in this study. The new reference plane in dental cast analysis corresponded to the A-PNS plane in the lateral view and to the J-J' plane in the frontal view, which have been shown to be sufficiently accurate as a reference for measurement. These results indicate that the application of this palatal reference plane, as a reference structure, should provide accurate and abundant 3-D data concerning malocclusion. 相似文献
919.
Kawabata H Nagai S Hayashi M Nakamura H Nagao T Shigematsu M Kitaichi M Izumi T 《Respirology (Carlton, Vic.)》2003,8(3):351-358
OBJECTIVE: The aim of this study was to determine whether the presence of lung shrinkage on CXR can predict diminished survival in patients with idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP). METHODOLOGY: In a hospital-based cohort study 68 subjects diagnosed with IPF/UIP by surgical lung biopsy or at autopsy were observed for a mean of 7.6 years. The radiographic scores from Cherniack's method, pulmonary function tests, arterial blood gas, and haematological data were obtained at initial presentation. Longitudinal radiographic changes over a mean interval of 2.7 years were measured. Survival analysis was performed using Kaplan-Meier and Cox's proportional hazards regression analysis. RESULTS: At some point during the observation period 36 (53%) of 68 patients did not exhibit lung shrinkage and 32 (47%) of 68 patients showed lung shrinkage. Patients with lung shrinkage were more likely to have a diminished survival than those with lung preservation; median survival was 4.4 vs 7.8 years, respectively. Lung shrinkage during the observation period (hazard ratio, 3.89; 95% CI = 1.68-9.01; P= 0.001) was associated with lower rates of survival. CONCLUSION: In patients with IPF/UIP, lung shrinkage on CXR during the observation period was a poor prognostic factor. 相似文献
920.