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81.

Background

Responses to continuous theta burst stimulation (cTBS) applied to the human primary motor cortex are highly variable between individuals. However, little is known about how to improve the after-effects of cTBS by adjusting the protocol characteristics.

Objective

We examined whether current directions adopted in the measurement of cortical motor excitability indexed as motor evoked potentials (MEPs) affect the responses to cTBS. We also tested whether the stimulus intensity of cTBS influences the after-effects.

Methods

Thirty-one healthy volunteers participated. The after-effects of cTBS with the conventional intensity of 80% of individual active motor threshold (AMT) (cTBS80%) were tested by measuring MEP amplitudes induced by not only posterior-anterior (PA) but also anterior-posterior (AP) and biphasic (PA-AP) currents. We also investigated cTBS with 65% AMT (cTBS65%) and 100% AMT (cTBS100%) in subjects who showed depression of MEP amplitudes after cTBS80%, as well as cTBS65% in subjects in whom facilitation of MEPs was induced by cTBS80%.

Results

Current directions in MEP measurement had no influence on the cTBS responses. In subjects whose MEPs were depressed by cTBS80%, cTBS100% partly induced MEP facilitation, while cTBS65% abolished the after-effects. In subjects who showed MEP facilitation by cTBS80%, cTBS65% partly induced MEP depression.

Conclusions

Stimulus intensity of cTBS influenced the responses to cTBS, and lowering stimulus intensity induced the expected after-effects of cTBS in some subjects.  相似文献   
82.
83.
A laparoscopic cholecystectomy (LC) was successfully performed on a 61-year-old man who had undergone coronary artery bypass grafting (CABG) using the right gastroepiploic artery (RGEA). He complained of right hypochondralgia 20 days after CABG. Gallstones were diagnosed and a cholecystectomy was performed 9 months after CABG. Under general anesthesia, the operation was performed using a pneumoperitonium. When a laparoscope was inserted, the RGEA pedicle could be clearly recognized. The pedicle obstructed the operating field and made the working space narrower than usual. No ST changes on the electrocardiogram were seen during LC, especially during the initiation of pneumoperitonium, the insertion of the ports, or when retracting the gallbladder. The postoperative course was uneventful. To avoid complications, care should be taken not to stretch the RGEA pedicle during LC, and careful monitoring of the electrocardiogram is also necessary. It is difficult to view the operating field and the RGEA pedicle together. It is therefore better to insert another laparoscope for concomitant monitoring of the RGEA pedicle. Received: June 25, 2001 / Accepted: January 8, 2002  相似文献   
84.
Tryptase is a protease released from mast cells and is believed to contribute to the inflammatory process in allergic diseases including asthma. In the course of screening to find tryptase inhibitors, we isolated two new tryptase inhibitors, cyclotheonamide E4 (3) and E5 (4), from a marine sponge of the genus Ircinia. The structures of these molecules were determined by interpretation of 1H and 13C NMR spectra, and they were shown to be closely related to the previously reported cyclotheonamides E (1), E2, and E3 (2). These molecules contain two unusual amino acids, vinylogous tyrosine and alpha-ketohomoarginine, which are involved in strong activities against serine proteases. Cyclotheonamide E4 showed potent inhibitory activity against human tryptase (IC50 5.1 nM). Therefore, cyclotheonamide E4 may be useful as a therapeutic agent in the treatment of allergic diseases including asthma.  相似文献   
85.
Histologically proven eosinophilic myelitis has rarely been reported except in connection with parasitism. To clarify its clinicopathological features, we conducted a nationwide survey of biopsy-proven eosinophilic myelitis of unknown cause throughout Japan. Six such cases were collected and studied immunologically and pathologically. All were young to middle-aged men. All showed a protracted and fluctuating course with mild disability for 3-25 (mean 12.5) months before biopsy. Magnetic resonance imaging revealed localized lesions of T2-high and T1-iso signal intensity with a partial gadolinium enhancement in all cases. Cerebrospinal fluid (CSF) examinations were completely normal except for modest pleocytosis in two cases. Eosinophilia was present in the peripheral blood in two cases but was absent from the CSF of all cases. In spite of the chronic nature of the disease, spinal cord pathology revealed very active lesions with marked cell infiltration consisting mainly of CD8(+) T cells and varying numbers of eosinophils in the perivascular areas and the parenchyma. Both the myelin and axons were severely disrupted in all cases. Moreover, eosinophil cationic protein (ECP), an activated eosinophil product, was heavily deposited in the tissues. All but one case had hyperIgEemia and mite antigen-specific IgE in the sera, and two had accompanying atopic disorders. The present study thus revealed idiopathic eosinophilic myelitis to be a localized and persistent inflammation of the spinal cord, with distinct clinicopathological features, that has a possible link to atopic diathesis.  相似文献   
86.
Hirata Y  Kiuchi K 《Brain research》2003,983(1-2):1-12
Glial cell line-derived neurotrophic factor (GDNF) activates c-Ret tyrosine kinase and several downstream intracellular pathways; the biological effects caused by the activation of each of these pathways, however, remain to be elucidated. Here we report the ability of GDNF to induce proliferation, rather than differentiation, of neuroblastoma cells (SH-SY5Y) by targeting the signaling pathway responsible for mediating this proliferative effect. GDNF induces the phosphorylation of Akt and p70S6 kinase (p70S6K) in SH-SY5Y cells in which Ret protein expression is relatively low. Interestingly, treating SH-SY5Y cells with retinoic acid greatly increases Ret protein levels and GDNF-induced Ret tyrosine phosphorylation, but does not affect the mitogenic action of GDNF and the activation of the Akt/p70S6K pathway. In contrast, the activation of the ERK pathway and the resulting induction of immediate-early genes parallel the increases in Ret protein levels. Rapamycin, a specific inhibitor of p70S6K activation by the mammalian target of rapamycin, completely prevents GDNF-induced proliferation and activation of p70S6K. These results suggest that GDNF promotes cell proliferation via the activation of p70S6K, independent of the ERK signaling pathway, and that GDNF activates the Akt/p70S6K pathway more efficiently than the ERK pathway in the cells in which Ret expression is low.  相似文献   
87.
The differentiation of composite resin from teeth using fluorescence emission was investigated as basic research for the visual detection of resin filled teeth in mass dental health examinations. Fluorescence spectra were taken from extracted human maxillary central incisors and 12 types of light-cured composite resins with a maximum of 15 shades via excitation using light with wavelengths of 400-500 nm. The fluorescence intensity ratio of resin to tooth was lowest around 500 nm for all the resins. The fluorescent images were taken based on spectroscopic results, which confirmed discrimination between the resin part and the tooth in the resin filled tooth.  相似文献   
88.
89.
Sperm from the caudal epididymis of 2 inbred strains of Sprague-Dawley (SD) rats, selected on the basis of their high- or low-shuttlebox avoidance responses, were analyzed for motion characteristics by a computer-assisted sperm motion analysis (CASA) system. Sperm motion in high-avoidance animals (HAA) was characterized by high velocities, high amplitude of lateral head displacement (ALH), and low beat cross frequency (BCF). Conversely, sperm from low-avoidance animals (LAA) displayed low velocities, low ALH, and high BCF. These characteristics in sperm motion were not changed by washing. Furthermore, after treatment with alpha-chlorohydrin (aCH) as a male antifertility agent affecting rat epididymal sperm motion, sperm velocities in HAA rats were significantly reduced to levels similar to those in untreated LAA rats. However, ALH and BCF in HAA rats treated with aCH were different from those in untreated LAA rats. Sperm adenosine triphosphate (ATP) content was higher in HAA than in LAA rats, correlating with values of their sperm velocities. These data suggest there are apparent strain differences in sperm motion between HAA and LAA rats and that these differences are dependent on factors, including sperm energy production.  相似文献   
90.
Tanaka M  Xiao H  Kiuchi K 《Neuroreport》2002,13(15):1913-1916
Glial cell-line neurotrophic factor (GDNF), a neurotrophic factor with heparin binding affinity, promotes the survival and differentiation of a variety of neuronal cells including dopaminergic neuron. The effect of heparin on GDNF signaling was investigated based on the expression of the tyrosine hydroxyrase (TH) gene in neurobalstoma cells. Up-regulation of TH gene mRNA by GDNF was enhanced by co-administration of heparin. This facilitation by heparin was particularly evident at suboptimal levels of GDNF, which was consistent with the luciferase assay using TH gene promoter. Pretreatment with heparitinase decreased TH promoter activity in the absence of heparin. Phosphorylation of extracellular regulated kinase was increased in the presence of heparin, although tyrosine phosphorylation of Ret receptor tyrosine kinase was not affected by heparin. Expression of early response genes such as c-fos or Egr1 increased and sustained in the presence of heparin more than that without heparin. These results indicate that interaction with glycosaminoglycans such as heparin affects GDNF signal transduction positively.  相似文献   
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