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971.
Adrenocorticotropic hormone is produced in the ventricle of patients with essential hypertension 总被引:4,自引:0,他引:4
Mizuno Y Yasue H Yoshimura M Harada E Fujii H Nakamura S Yamamoto N Ogawa H Nakao K 《Journal of hypertension》2005,23(2):411-416
OBJECTIVE: Aldosterone is produced in the ventricle of patients with hypertension. The present study was designed to examine whether adrenocorticotropic hormone (ACTH) and cortisol are also produced from the heart in patients with essential hypertension. METHODS: The study population consisted of 57 patients with essential hypertension and 28 control subjects. Plasma levels of ACTH, aldosterone, and cortisol were measured in the aortic root, the anterior interventricular vein and the coronary sinus during cardiac catheterization. RESULTS: The plasma levels of ACTH were significantly higher at the anterior interventricular vein and coronary sinus than at the aortic root (12.7 +/- 1.0 versus 10.7 +/- 0.9 pmol/l, P < 0.001; and 12.3 +/- 1.0 versus 10.7 +/- 0.9 pmol/l, P < 0.001, respectively) in the hypertension group, whereas there were no significant differences in the levels among these sites in the control group. The plasma levels of aldosterone were significantly higher at the anterior interventricular vein and the coronary sinus than at the aortic root (261.7 +/- 16.4 versus 239.1 +/- 15.1 pmol/l, P < 0.001; and 258.8 +/- 17.0 versus 239.1 +/- 15.1 pmol/l, P < 0.01, respectively) in the hypertension group, whereas there were no significant differences in the levels among these sites in the control group. CONCLUSIONS: ACTH as well as aldosterone is produced, but cortisol is not produced, from the ventricle of patients with essential hypertension. 相似文献
972.
Sakata C Kinoshita T Kaminou T Adachi A Kinoshita F Ogawa T 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》2005,65(3):278-280
Synovial sarcomas are a less common cervical tumor in young patients. We report a 23-year-old man with synovial sarcoma in the submandibular region. T2-weighted MR images demonstrated a mixed-intensity tumor attached to the submandibular gland. T1-weighted MR images revealed a focal area with mildly increased signal intensity, indicating intratumoral hemorrhage. MR images were also useful for visualization of tumor extension. Synovial sarcoma should be considered in the differential diagnosis of well-defined inhomogeneous tumors adjacent to the submandibular gland in young adults. 相似文献
973.
Shinohara Y Kinoshita T Sugihara S Kinoshita F Matsusue E Fujii S Sakata C Tanabe Y Ogawa T 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》2005,65(4):353-358
PURPOSE: To evaluate the usefulness of MR imaging for the detection of severe facial nerve damage in patients with facial nerve palsy. MATERIALS AND METHODS: We retrospectively reviewed 26 consecutive patients with facial nerve palsy (13 non-responders and 13 responders). T1-weighted, T2-weighted, and postcontrast T1-weighted images were obtained in all patients. FLAIR images were also obtained in 3 non-responders. RESULTS: The geniculate ganglion, labyrinthine segment, and tympanic segment or mastoid segment showed high signal intensity on T2-weighted images in 9 of 13 non-responders, whereas high signal intensity of the nerve was only seen in 1 of 13 responders. FLAIR imaging revealed high signal intensity lesions of the distal intrameatal segment in 2 non-responders. Contrast enhancement of the facial nerve showed a similar pattern in non-responders and responders. High signal intensity lesions on T2-weighted or FLAIR images showed enhancement on postcontrast T1-weighted images. CONCLUSION: These results suggest that a high signal intensity area on T2-weighted images is a marker of severe facial nerve damage. FLAIR imaging is useful for identification of T2-prolongation in the distal intrameatal segment. 相似文献
974.
Ogasawara K Inoue T Kobayashi M Endo H Yoshida K Fukuda T Terasaki K Ogawa A 《AJNR. American journal of neuroradiology》2005,26(2):252-257
BACKGROUND AND PURPOSE: Cerebral hyperperfusion syndrome is a rare but serious complication of carotid endarterectomy (CEA). The aim of the present study was to determine whether intraoperative blood flow velocity (BFV) monitoring in the middle cerebral artery (MCA) by using transcranial Doppler ultrasonography (TCD) could be used as a reliable technique to detect cerebral hyperperfusion following CEA by comparing findings with those of brain single photon emission CT (SPECT). METHODS: Intraoperative BFV monitoring was attempted in 67 patients undergoing CEA for treatment of ipsilateral internal carotid artery (ICA) stenosis (> or =70%). Cerebral blood flow (CBF) was also assessed using SPECT, which was performed before and immediately after CEA. RESULTS: Intraoperative BFV monitoring was achieved in 60 patients. Of the 60 patients, post-CEA hyperperfusion (CBF increase > or =100%, compared with preoperative values) was observed in six patients. The sensitivity, specificity, and positive predictive value of the BFV increases immediately after declamping of the ICA for detecting post-CEA hyperperfusion was 100%, 94% and 67%, respectively, with a cut-off point 2.0-fold that of preclamping BFV. The sensitivity and specificity of the BFV increases at the end of the procedure for detecting post-CEA hyperperfusion were 100% for both parameters, with cut-off points of 2.0- to 2.2-fold BFV of preclamping value. Hyperperfusion syndrome developed in two patients with post-CEA hyperperfusion, but intracerebral hemorrhage did not occur. In one of these two patients, BFV monitoring was not possible because of failure to obtain an adequate bone window. CONCLUSION: Intraoperative MCA BFV monitoring by using TCD is a less reliable method to detect cerebral hyperperfusion following CEA than postoperative MCA BFV monitoring, provided adequate monitoring can be achieved. 相似文献
975.
Pallidoreticular damage in acute carbon monoxide poisoning: diffusion-weighted MR imaging findings 总被引:2,自引:0,他引:2
Kinoshita T Sugihara S Matsusue E Fujii S Ametani M Ogawa T 《AJNR. American journal of neuroradiology》2005,26(7):1845-1848
We describe a case of carbon monoxide poisoning that led to pallidoreticular damage and delayed leukoencephalopathy. Serial diffusion-weighted MR imaging was performed. A restricted water diffusion pattern was demonstrated in the globus pallidus and substantia nigra in the early stage. Diffusion-weighted imaging is useful for early identification of the effects of acute carbon monoxide poisoning. 相似文献
976.
Fukazawa R Sonobe T Hamamoto K Hamaoka K Sakata K Asano T Imai T Kamisago M Ohkubo T Uchikoba Y Ikegami E Watanabe M Ogawa S 《Pediatric research》2004,56(4):597-601
ACE I/D and AT1R 1166A/C polymorphisms are considered to comprise individual risk factors for the development of coronary disease. We sought to demonstrate that the ACE I/D and AT1R 1166A/C polymorphisms affect coronary artery stenosis in patients with Kawasaki disease (KD). We examined 147 healthy controls and 281 Japanese children with KD. The patients were further divided into group N (n = 246, no ischemia) and group I (n = 35, severe coronary artery stenosis with myocardial ischemia), and we studied the genotype of ACE I/D and AT1R 1166A/C polymorphisms. We also examined ACE activity in patients with acute KD. We did not detect any prevalent genotypes of the ACE and AT1R polymorphisms between controls and KD patients. However, the prevalence of the D allele in the ACE polymorphism and of the C allele in the AT1R polymorphism tended to be higher in group I than in group N (odds ratios, 2.00 and 2.32, respectively). In addition, the presence of the D and/or C alleles significantly increased the relative risk of developing myocardial ischemia (odds ratio, 2.71; p = 0.038). During the convalescent phase of KD, ACE activity was increased despite significant attenuation during the acute phase. These results suggested that the renin-angiotensin system is associated with the formation of severe coronary artery stenosis and myocardial ischemia. 相似文献
977.
Halothane and propofol modulation of gamma-aminobutyric acidA receptor single-channel currents 总被引:3,自引:0,他引:3
Kitamura A Sato R Marszalec W Yeh JZ Ogawa R Narahashi T 《Anesthesia and analgesia》2004,99(2):409-15, table of contents
Halothane and propofol enhance the activity of the gamma-aminobutyric acid (GABA) system, which is one of the most important systems in the mechanism of anesthesia. To determine whether halothane and propofol enhance GABAergic responses by the same mechanism, we performed single-channel patch-clamp experiments with rat cortical neurons in primary culture. Each of the open-time and closed-time distributions of GABA(A) receptor single channels was expressed by a sum of fast and slow time constants. Neither halothane nor propofol changed the single-channel conductance. Halothane increased the probability of the channel being open via a prolongation of the slow phase of open time, whereas propofol increased the channel open probability via a shortening of the slow phase of closed time. Thus, although both halothane and propofol augmented the channel open probability, thereby causing an increase in charge transfer during inhibitory transmitter action, they acted by different mechanisms. 相似文献
978.
Smad3 deficiency attenuates renal fibrosis, inflammation,and apoptosis after unilateral ureteral obstruction 总被引:12,自引:0,他引:12
Inazaki K Kanamaru Y Kojima Y Sueyoshi N Okumura K Kaneko K Yamashiro Y Ogawa H Nakao A 《Kidney international》2004,66(2):597-604
BACKGROUND: Transforming growth factor-beta (TGF-beta) has been implicated in the development of renal fibrosis induced by unilateral ureteral obstruction (UUO). However, there is little information on signaling pathways mediating TGF-beta activity involved in molecular and cellular events leading to renal fibrosis induced by UUO. In this study, we sought to determine whether Smad3, a major signaling component of TGF-beta, mediated renal fibrosis induced by UUO. METHODS: Renal fibrosis, inflammation, and apoptosis induced by UUO were macroscopically and histologically compared between wild-type mice and Smad3 null mice. RESULTS: Gross appearance of the kidney after UUO showed relatively intact kidney in Smad3 null mice [Smad3(-/-) mice] when compared with that of wild-type mice [Smad3(+/+) mice]. Renal interstitial fibrosis based on the interstitial area stained with Aniline-blue or Sirius red solution was significantly attenuated in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Deposition of type I and type III collagens were also significantly reduced in the obstructed kidney of Smad3(-/-) mice. In addition, the numbers of myofibroblasts, macrophages, and CD4/CD8 T cells infiltrated into the kidney after UUO were significantly attenuated in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Furthermore, terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) staining after UUO showed significantly reduced number of tubular apoptotic cells in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Endogenous Smad pathway was activated in the obstructed kidney after UUO in wild-type mice as judged by the increase of phosphorylated Smad2 or phosphorylated Smad2/3-positive cells in renal interstitial area. CONCLUSION: Smad3 deficiency attenuated renal fibrosis, inflammation, and apoptosis after UUO, suggesting that Smad3 was a key molecule mediating TGF-beta activity leading to real fibrosis after UUO. 相似文献
979.
BACKGROUND: Magnetic resonance imaging (MRI) can provide a preoperative diagnosis of gliomatosis cerebri, but the findings sometimes do not correspond with the clinical symptoms or histologic findings. CASE DESCRIPTION: Three-dimensional anisotropy contrast (3DAC) imaging was used to assess damage to the neuronal fibers in two patients with gliomatosis cerebri who presented with only mental deterioration. Conventional MRI depicted markedly abnormal findings consisting of widespread areas of abnormally high signal intensity in the corpus callosum and in the bilateral white matter in both cases. In contrast, 3-D AC imaging showed no abnormality except for small dark areas in the corpus callosum or white matter. CONCLUSION: 3-D AC imaging provides more accurate information about damage to the neuronal fibers in cases of gliomatosis cerebri than other MRI techniques. 相似文献
980.
Nakatani Y Miyagi Y Takemura T Oka T Yokoi T Takagi M Yokoyama S Kashima K Hara K Yamada T Nozawa A Inayama Y Sakamoto K Ogawa N Kitamura H Resl M Cho SH Koss MN Mark EJ 《The American journal of surgical pathology》2004,28(7):921-927
It is now known that gene mutation of beta-catenin with subsequent nuclear/cytoplasmic (N/C) overaccumulation of the protein plays an important role in tumorigenesis of various organs. We recently demonstrated that low-grade adenocarcinoma of the fetal lung type (L-FLAC)/well-differentiated fetal adenocarcinoma (WDFA), the epithelial prototype of classic pulmonary blastoma (CPB), shows N/C localization of beta-catenin with genetic mutation. This prompted us to further investigate the state of beta-catenin abnormality in CPB and related neoplasms. We studied 9 lung tumors previously diagnosed as biphasic pulmonary blastoma (PB). Histologically, 4 cases (median age 34 years) were CPB with l-FLAC/WDFA as the epithelial component, whereas 5 cases (median age 65 years) were a variant of carcinosarcoma with high-grade FLAC/clear cell adenocarcinoma with fetal lung features as the epithelial component, which we term the blastomatoid variant of carcinosarcoma (BCS). Immunohistochemically, all 4 CPBs showed aberrant N/C localization of beta-catenin both in the epithelial and mesenchymal components, with especially high staining intensity in the budding glands and morules. In contrast, all 5 BCSs showed preserved or diminished membranous expression and no significant N/C expression of beta-catenin in the epithelial component, and absent or focal N/C expression of beta-catenin in the mesenchymal component. Mutational analysis of exon 3 of the beta-catenin gene revealed that 3 CPBs harbored missense mutations (S29F, S37F, and S37F), whereas none of the 5 BCSs had this mutation. This study suggests that beta-catenin gene mutations may play a role in the tumorigenesis of CPB. Although CPB and BCS have often been grouped together as biphasic PB, they are different entities based on immunohistochemical and molecular analysis of beta-catenin. Immunostaining for beta-catenin is useful for the discrimination. 相似文献