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101.
Sympathetic nerves and adrenal medulla: contributions to cardiovascular-conditioned emotional responses in spontaneously hypertensive rats 总被引:1,自引:0,他引:1
This report investigates the contributions of the sympathetic nerves and adrenal medulla to resting mean arterial pressure (MAP) and to emotionally conditioned MAP and heart rate (HR) responses in unrestrained spontaneously hypertensive rats (SHR) and Wistar-Kyoto normotensive control rats (WKY). Resting MAP (in mm Hg), which was higher in SHR (WKY = 120 +/- 4; SHR = 163 +/- 4; p less than 0.01), did not differ in the two strains following chemosympathectomy (WKY = 105 +/- 2; SHR = 101 +/- 2; n.s.). Adrenal medullectomy did not affect resting MAP in WKY (125 +/- 6; n.s.) but lowered it in SHR (146 +/- 5; p less than 0.05), relative to controls (see above). The conditioned pressor response (in mm Hg) in controls consisted of two peaks (I, II) in both strains, but was exaggerated in SHR (I = WKY, 13 +/- 1; SHR, 25 +/- 2; p less than 0.01; II = WKY 10 +/- 2; SHR 20 +/- 2; p less than 0.01). Chemosympathectomy suppressed (relative to controls) the first peak, but not the second, in both strains (WKY: I = 4 +/- 1, p less than 0.01; II = 12 +/- 2, n.s.; SHR: I = 6 +/- 1, p less than 0.01; II = 15 +/- 2, n.s.). Adrenal medullectomy alone had little effect on the pressor response, but when combined with chemosympathectomy both peaks were largely eliminated (WKY: I = 2 +/- I; II = 5 +/- 1; SHR: I = 1 +/- 0; II = 2 +/- 0). These data indicate that: 1) hypertension in conscious, freely behaving SHR is largely sustained by the sympathetic vasomotor nerves but that the adrenal medulla contributes to the magnitude of the elevation; 2) the early component of the exaggerated pressor response during aversive stimulation is mediated by sympathetic vasomotor excitation; and 3) the later component of the exaggerated pressor response reflects coactivation of the sympathetic vasomotor nerves and the adrenal medulla. 相似文献
102.
Koji Aoyama Masako Tsuchiya Kenji Mori Yoshitsugu Kubo Kei Shiraishi Eiki Sakaguchi Satoyoshi Yamashita Isao Sakaida 《Hepatology research》2007,37(8):608-614
Aims: We have reported that one-week administration of a late evening snack (LES) improved not only malnutrition but also glucose intolerance in hospitalized patients with liver cirrhosis. Thus, we investigated whether long-term LES administration to outpatients for 3 months could reproduce the results obtained from hospitalized patients, especially improved glucose intolerance. If this treatment aggravated glucose intolerance, we tried to find any marker predicting this aggravation before the treatment. Methods: Outpatients were prescribed one pack of oral supplementation of a branched-chain amino acid (BCAA)-enriched nutrient, Aminoleban EN (210 kCal) as a LES without dietician supervision. Both before LES administration and after 3 months, glucose tolerance and liver function were examined using a 75 g oral glucose tolerance test (OGTT), biochemical parameters in blood and the relationship between glucose tolerance (area under the curve (AUC)) and the following serum markers. Results: Branched-chain amino acid/tyrosine ratio (BTR), the number of red blood cells (RBC), and hematocrit (Ht) significantly increased, with significant reduction of blood NH(3) level in patients with a blood glucose level less than 200 mg/dL 2 h after 75 g OGTT. However, the increase of AUC was seen after 3 months of LES administration in patients who had blood glucose higher than 200 mg/dL 2 h after 75 g OGTT. AUC weakly correlated positively with serum 7S collagen and negatively with choline esterase (ChE) and albumin (Alb). Conclusion: 75 g OGTT is a useful marker to predict the worst outcome and avoid the adverse effect of LES treatment in liver cirrhosis patients if performed without adequate nutrient conduct by a dietician. 相似文献
103.
104.
To understand the mechanisms that control life span and age-related phenotypes, we used two-dimensional (2D) gel electrophoresis to study the intracellular proteins whose amounts change during the process of cellular aging. We found that the amount of an alpha-2-macroglobulin (A2M) fragment derived from culture medium increased in the cells with aging. A2M is linked to Alzheimer's disease both genetically and functionally. This is the first report of accumulation of an A2M fragment in senescent fibroblasts. We also studied 2D gel profiles of human fibroblasts immortalized by treatment with either 60Co gamma rays or 4-nitroquinoline 1-oxide. As immortalized cells overcome cellular senescence to gain an unlimited life span, the proteins whose amounts change after immortalization may be relevant to the age-related phenotypes. 2D gel analysis revealed that the A2M fragment was down-regulated in the immortalized cells, compared with their normal counterparts, regardless of their passage. We also found that the other four proteins increased in amount with aging and decreased in amount after immortalization. Our results suggest: (1) the A2M incorporation into the cells is increased in the process of cellular aging; and (2) A2M may be linked to the age-related phenotypes that were lost during the process of immortalization of human cells. 相似文献
105.
K Sakaguchi R Hattori Y Yui Y Takatsu T Susawa N Yui H Nonogi S Tamaki C Kawai 《British heart journal》1986,55(5):434-438
Changes in platelet alpha 2 adrenoreceptors and their relation to plasma catecholamine concentrations were studied in 11 patients with acute transmural myocardial infarction. A radiolabelled alpha 2 adrenoreceptor antagonist, [3H]-yohimbine, was used to assay alpha 2 adrenoreceptors on platelet membranes, and plasma catecholamine concentrations were measured by high performance liquid chromatography. The number of platelet alpha 2 adrenoreceptors, the dissociation constant, and plasma noradrenaline and adrenaline concentrations were studied 6.6 (3.3) (mean (SD)) hours after the onset of acute myocardial infarction and one month later. The mean (SD) number of adrenoreceptors increased significantly from 94.5 (50.5) fmol/mg protein immediately after infarction to 157.0 (65.7) fmol/mg protein one month later. The dissociation constant, however, did not change significantly (4.33 (1.40) nmol/l vs 4.37 (1.22) nmol/l). Raised noradrenaline (5.60 (4.37) nmol/l) and adrenaline (0.28 (0.14) nmol/l) concentrations had fallen significantly to normal values (1.21 (0.67) and 0.09 (0.05) nmol/l respectively) a month after infarction. The decrease in the number of alpha 2 adrenoreceptors soon after infarction may be beneficial because such a change will reduce the strength of various reactions to catecholamines, such as vasoconstriction. 相似文献
106.
S Kobayashi T Takeda M Enomoto A Tamori N Kawada D Habu H Sakaguchi T Kuroda K Kioka S R Kim T Kanno T Ueda M Hirano S Fujimoto H Jomura S Nishiguchi S Seki 《Liver international》2007,27(2):186-191
BACKGROUND: Interferon (IFN) improves hepatic inflammation/fibrosis and reduces the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C (CH-C). However, HCC develops in some patients who have a sustained virological response (SVR) to IFN therapy. We designed this study to establish a follow-up protocol for patients with CH-C who have SVR to IFN therapy. METHODS: We retrospectively studied 1124 patients with CH-C who received IFN. RESULTS: HCC developed in 3.5% of patients with SVR to IFN. As compared with SVR patients without HCC, SVR patients with HCC were predominantly male (P=0.003), older at the initiation of IFN therapy (P=0.002), and at a more advanced histologic stage of disease (P<0.001). However, three of the 13 SVR HCC patients had mild fibrosis. The mean interval from IFN therapy to the detection of HCC in SVR HCC patients was 5.8 years and did not differ significantly from that in non-SVR HCC patients (P=0.304). Although most patients with HCC received curative therapy, the prognosis of some SVR HCC patients was poor, probably because of insufficient follow-up, resulting in delayed detection of HCC. CONCLUSIONS: SVR patients with CH-C who are elderly, male, or have an advanced histologic stage are at a high risk for the development of HCC after IFN therapy. We recommend that SVR patients should be observed carefully for more than 10 years after the completion of IFN therapy, even if they only have early fibrosis. 相似文献
107.
Naturally arising CD25+CD4+ regulatory T cells play key roles in the maintenance of immunologic self-tolerance and negative control of various immune responses. The majority, if not all, of them are produced by the normal thymus as a functionally distinct T-cell subpopulation, and their generation is in part developmentally controlled. Genetic abnormality in the development and function of this population can indeed be a cause of autoimmune disease, immunopathology, and allergy in humans. This regulatory population can be exploited to prevent and treat autoimmune disease by strengthening and reestablishing immunologic self-tolerance. 相似文献
108.
Karin Ashizawa Kanako Ogura Shunsuke Nagase Asumi Sakaguchi Joji Tokugawa Makoto Hishii Masaharu Fukunaga Takanori Hirose Toshiharu Matsumoto 《Pathology international》2021,71(10):697-706
An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry. 相似文献
109.
Daisuke Yoshioka Koichi Toda Taichi Sakaguchi Shigeru Miyagawa Hiroyuki Nishi Yasushi Yoshikawa Satsuki Fukushima Shunsuke Saito Tetsuya Saito Ikuko Shibasaki Yasushi Sakata Tomohito Ohtani Yoshiki Sawa 《Journal of artificial organs》2013,16(3):386-388
Continuous-flow left ventricular assist devices (LVADs) provide acceptable clinical results, but the long waiting period for heart transplantation leads to diverse complications. LVAD support can cause reverse left ventricular (LV) remodeling that results in the improvement of LV function and allows LVAD removal. We present a case of successful removal of a DuraHeart LVAD because of sufficient recovery of LV function. Before LVAD removal, we conducted an “LVAD weaning test” by decreasing pump speed and performing an additional normal saline infusion test. We consider that the LVAD weaning test can be used in place of the “pulsatile LVAD off test.” 相似文献
110.
Apparent diffusion coefficient as a potential surrogate marker for Ki‐67 index in mucinous breast carcinoma 下载免费PDF全文