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941.
We report a patient who exhibited transient palinopsia and visual hallucinations. Disturbances initially included an auditory component and increasingly were localized to the left visual field. These events occurred during recovery from a right subcortical hematoma with left homonymous hemianopia. Single-photon emission computed tomography (SPECT) demonstrated extensive perilesional hyperperfusion involving parts of the right parietal, temporal, and occipital cortex. Perilesional hyperperfusion disappeared as the visual abnormalities diminished. We believe that excitatory neuronal activation in perilesional cortex during recovery contributed importantly to the transient abnormal perceptions.  相似文献   
942.
Systemic administration of 3-nitropropionic acid (3-NPA, a mycotoxin) induces brain damage accompanied by disturbance in the blood-brain barrier (BBB). Since the endothelial cells are important components of the BBB and the first target of a systemic intoxication, in the present study, the effect of 3-NPA on primary cultured rat brain endothelial cells (rBECs) was examined by studying intracellular Ca(2+) ([Ca(2+)](i)) response using imaging techniques with fura-2. rBECs were prepared using a method of Kis et al. [Eur. J. Pharmacol. 368 (1999) 35-42] and Szabo et al. [Neurobiology 5 (1997) 1-16]. Almost all cells were immunoreactive to antibody against the factor VIII-related antigen (von-Willebrand factor). They showed a typical dose-dependent increase of [Ca(2+)](i) in response to ATP or bradykinin. Low concentrations of 3-NPA (1.7 mM, 3.4 mM) caused no changes, and a medium concentration (6.8 mM) increased the [Ca(2+)](i) gradually and progressively, and the increase was reversed incompletely back to the resting level after washing. A high concentration (13.6 mM) increased the [Ca(2+)](i) irreversibly. These elevations of [Ca(2+)](i) were absent in a Ca(2+)-free medium. In endothelial cells treated with 17beta-estradiol (above 10(-5) M) or with a selective estrogen receptor modulator, tamoxifen (5 x 10(-7) M), no elevation of [Ca(2+)](i) was observed with 3-NPA treatment. The response to ATP was impaired after application of 3-NPA, but it was preserved by cotreatment with 17beta-estradiol or tamoxifen. An estrogen receptor antagonist ICI 182,780 inhibited these effects by 17beta-estradiol or tamoxifen. Lysosomal neutral red uptake and TUNEL experiments revealed the necrotic but not apoptotic cell death at least in this acute stage. Data indicate that a medium to high concentration of 3-NPA induces damage on rBECs as revealed by an accumulation of [Ca(2+)](i), but the damage was protected by cotreatment with 17beta-estradiol or tamoxifen, suggesting that estrogen may be protective for the brain vascular damage via estrogen receptor.  相似文献   
943.
IL-6 is a multifunctional cytokine involved in regulation of differentiation, antibody production, and growth of certain types of tumor cells. Its excessive production plays a major role in pathogenesis of multiple myeloma and postmenopausal osteoporosis. In the course of a screening program aimed at IL-6 inhibitor from microbial products, we found madindoline A (MDL-A) and madindoline B, which have a fuloindoline structure with diketocyclopentene bound to the methyl group. MDL-A has no cytotoxic activities. It inhibited only activities of both IL-6 and IL-11 without affecting the IL-6-specific signal transduction cascade, JAK2/STAT3. In a dose-dependent manner [(3)H]MDL-A binds to gp130, which is a signal transducing 130-kDa glycoprotein, but formation of the trimeric complex IL-6/IL-6 receptor/gp130 was not inhibited, suggesting that MDL-A suppresses dimerization of trimeric complexes. Not only did MDL-A markedly inhibit IL-6- and IL-11-induced osteoclastogenesis in vitro, but it also inhibited IL-6-stimulated serum amyloid A production and bone resorption in an experimental model of postmenopausal osteoporosis in vivo by a different mechanism from that of 17beta-estradiol. Here we show that MDL-A has a highly selective inhibitory effect on IL-6 and IL-11 activities by inhibiting a gp130 activity while suppressing bone loss in ovariectomized mice. MDL-A is anticipated as a lead compound for treatment of hormone-dependent postmenopausal osteoporosis, which has no serious side effects, and as a new mechanism of action, gp130 blocking.  相似文献   
944.
INTRODUCTION: The muscle bundles within the ligament of Marshall (LOM) are electrically active. The importance of these muscle bundles (Marshall bundle [MB]) to atrial activation and the generation of the ECG P wave is unclear. METHODS AND RESULTS: We used optical mapping techniques to study epicardial activation patterns in isolated perfused left atrium in four dogs. In another seven dogs, P waves were studied before and after in vivo radiofrequency (RF) ablation of the connection between coronary sinus (CS) and the LOM. Computerized mapping was performed before and after RF ablation. Optical mapping studies showed that CS pacing resulted in broad wavefronts propagating from the middle and distal LOM directly to the adjacent left atrium (LA). Serial sections showed direct connection between MB and LA near the orifice of the left superior pulmonary vein in two dogs. In vivo studies showed that MB potentials were recorded in three dogs. After ablation, the duration of P waves remained unchanged. In the other four dogs, MB potentials were not recorded. Computerized mapping showed that LA wavefronts propagated to the MB region via LA-MB connection and then excited the CS. After ablation, the activation of CS muscle sleeves is delayed, and P wave duration increased from 65.3 +/- 14.9 msec to 70.5 +/- 17.2 msec (P = 0.025). CONCLUSION: In about half of the normal dogs, MB provides an electrical conduit between LA free wall and CS. Severing MB alters the atrial activation and lengthens the P wave. MB contributes to generation of the P wave on surface ECG.  相似文献   
945.
As a current attention of the medical treatment has been paid to improve guality of the life rather than to save the life of the patient, so the treatment of bone and joint diseases, which are not ordinarily fatal and deteriorate quality of the life of the patient, would become important in the aged society of 21 century. In a strategy to improve the quality of life in the patient with osteoarthritis, disease modifying anti-osteothritis drugs are investigated for primary prevention and complete recovery of osteoarthritis. In osteoporosis, a characteristic bone disease of the aged, aims of the treatment have been changed from freeing of pain in the nineteen sixties, increase of bone mass in the nineteen eighties and reduction of the fracture rate in the nineteen nineties to improve of quality of the life through decrease of pain and fracture in 21 century. In conclusion, current management for bone and joint diseases in the elderly is finally designed to enjoy a healthy life of long span by medical intervention.  相似文献   
946.
A 68-year-old woman with idiopathic thrombocytopenic purpura (ITP) was admitted to our hospital with acute myocardial infarction on 7 February 1999. She had been treated since 1991 for mitral stenosis and regurgitation, atrial fibrillation due to mitralism, diabetes mellitus, hypertension, hyperlipidemia. Chest radiograph on admission showed cardiomegaly with congestion and cardiothoracic ratio was 63%. The platelet count on admission was 22,000/microliter, but she did not have petechia or purpura. Urgent coronary angiography revealed total occlusion in segment 7, and 13 and 75% stenosis in segment 4PD, 9 and 10. Subsequently, direct percutaneous transluminal coronary angioplasty (PTCA) was performed in segment 7. Dissection occurred during the intervention, and a coronary stent was implanted, we started heparin infusion and medication with ticlopidine hydrochloride as post-stenting therapy after the intervention, and there was no bleeding tendency.  相似文献   
947.
We describe a case of false aneurysm due to loosening of the anastomotic sutures 5 years after graft replacement for subacute type A aortic dissection. Leakage from the graft was controlled by tightening the suture slack indicating that suture loosening was the cause of the aneurysm. The mechanism was probably the progressive thinning of the edematous swollen aortic wall over the years causing the sutures to loosen.  相似文献   
948.
PURPOSE: To evaluate magnetic resonance (MR) imaging findings of radiation-induced cranial arteritis regarding arterial wall thickening and degree of enhancement, as well as to compare the findings with those of idiopathic moyamoya disease. MATERIALS AND METHODS: We reviewed cerebral MR images in five patients with radiation-induced large cerebral arteritis. All patients had undergone irradiation 2-25 years prior to this study. Conventional nonenhanced MR, MR angiographic, and contrast material-enhanced MR images were evaluated. Special attention was paid to wall enhancement of the affected arteries (distal internal carotid artery). Wall enhancement was staged in three levels by two neuroradiologists. We also reviewed MR images in 18 patients with primary moyamoya disease for comparison and analyzed them statistically (Fisher exact test). RESULTS: Wall thickening and prominent ring enhancement of the wall of the affected large cerebral arteries were observed in all (five of five) patients with radiation-induced arteritis. In contrast, wall thickening and prominent ring enhancement of the wall of the occluded arteries either were not seen (13 of 18 patients) or were faint (five of 18 patients) in patients with moyamoya disease. Contrast enhancement of the arterial walls in patients with radiation-induced arteritis was significantly more prominent than in patients with moyamoya disease (P =.003). CONCLUSION: MR images of wall thickening and prominent ring enhancement of the wall of affected large cerebral arteries may be a diagnostic clue in differentiating radiation-induced arteritis from moyamoya disease.  相似文献   
949.
We report granular cell tumor in the right SI nerve root, a location which has not been reported previously. The tumor showed heterogeneous hypointensity on T2-weighted images and heterogeneous enhancement. MRI also demonstrated the precise relation between the tumor and the nerve root.  相似文献   
950.
Diffusion-weighted MR imaging has been applicable to the differential diagnosis of abscesses and necrotic or cystic brain tumors. However, restricted water diffusion is not necessarily specific for brain abscess. We describe ring-enhancing metastases of lung carcinoma characterized by high signal intensity on diffusion-weighted MR images. The signal pattern probably reflected intralesional hemorrhage. The present report adds to the growing literature regarding the differential diagnosis of ring-enhancing brain lesions.  相似文献   
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