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1.
Jun Agata Nobuyuki Ura Hideaki Yoshida Yasuyuki Shinshi Haruki Sasaki Masaya Hyakkoku Shinya Taniguchi Kazuaki Shimamoto 《Hypertension research》2006,29(11):865-874
Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2. 相似文献
2.
Yutaka Okishio Tadayoshi Takeuchi Akikazu Fujita Kiyotaka Suenaga Kaori Fujinami Satoru Munakata Tadashi Takewaki Fumiaki Hata 《Journal of Smooth Muscle Research》2005,41(3):163-174
Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum. 相似文献
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5.
Ryuichi Matsumoto I. Nakano Nobutaka Arai Minami Suda Masaya Oda 《Acta neuropathologica》1996,92(6):640-644
This report concerns a notable case of progressive supranuclear palsy exhibiting asymmetric dentate nucleus and thalamic
degeneration with numerous torpedoes. The neuronal loss in the ventral lateral nucleus of the thalamus was predominant on
the right side, while in the cerebellum, a quantitative study revealed the contralateral predominance of the neuronal loss
in the dentate nuclei and torpedo formation, with preserved Purkinje cells. The abnormal tau-protein-related profiles in the
two nuclei did not show any laterality in their distribution, indicating that the dentatothalamic tract may have been affected
in a non-specific way in this case. In addition, the fact that the prominent sites of torpedo formation and loss of dentate
nucleus neurons are identical supports the hypothesis that the torpedoes may be formed in association with neuronal loss in
the dentate nucleus because of a plausible metabolic change in Purkinje cells through synaptic detachment of their axon terminals.
Received: 4 January 1996 / Revised: 27 March 1996 / Accepted: 5 April 1996 相似文献
6.
Takayoshi Sakai Seiji Iida Mitsunobu Kishino Masaya Okura Mikihiko Kogo 《Journal of oral pathology & medicine》2006,35(6):376-378
Sialolipoma is a new variant of salivary gland lipoma, which was first proposed by Nagao et al. (Histopathology 2001; 38: 30) in 2001. We report this rare case of sialolipoma in the hard palate. A 60-year-old Japanese woman was referred to our department complaining of a painless swelling on the right side of the hard palate. Intra-oral examination revealed a soft, elastic, dome-shaped mass with 1 cm in diameter located in the posterior part of the hard palate. Magnetic resonance imaging examination revealed high intensity on T(1)-weighted image and isointensity on T(2)-weighted image. Incisional biopsy revealed that the tumor was encapsulated by fibrous tissue, consisted of adipose tissue, and also contained normal salivary gland tissue peripherally. First diagnosed as an ordinary lipoma of the hard palate, the tumor was excised. According to the recent criteria of histologic findings of sialolipoma, we rediagnosed the tumor as sialolipoma of the hard palate. 相似文献
7.
The possibility that idiotypes (Ids) defined on anti-double stranded DNA (dsDNA) antibodies during active and inactive stages of lupus (1/84 Id and 4/90 Id, respectively) were expressed on anti-DNA antibodies during a subsequent active period (9/90) of the disease was investigated in a lupus patient with lupus cerebritis. Using rabbit (R)-anti-Ids specific to 1/84 Id and 4/90 Id in inhibition assays, the 4/90 Id was shown to be expressed on the framework regions of anti-single stranded DNA (ssDNA) but poorly on co-existing anti-dsDNA antibodies of active (9/90) stage. The 1/84 Id was poorly expressed on both types of 9/90 anti-DNA antibodies. While the 9/90 anti-ssDNA significantly bound to immobilized ssDNA and several single-stranded polynucleotides, only ssDNA inhibited the binding of the anti-ssDNA to ssDNA, suggesting its monospecificity toward ssDNA. Western blot analysis following isoelectric focusing showed that a spectrotype pattern of 4/90 Id-positive 9/90 anti-ssDNA IgG was similar to that of the 4/90 anti-dsDNA, suggesting that they are of related clonal origin. The present study suggests the idiotypic heterogeneity of anti-DNA antibodies and the shift of antigen specificity within an idiotypically related anti-DNA population during exacerbation of the disease. 相似文献
8.
Postoperative bronchial stump fistula responding well to occlusion with metallic coils and fibrin glue via a tracheostomy: a case report. 总被引:3,自引:0,他引:3
Junzo Shimizu Masaya Takizawa Tsuyoshi Yachi Yoshihiko Arano Yasumitsu Hirano Ryuichi Waseda Shiro Takahashi Yoshio Tsunezuka 《Annals of thoracic and cardiovascular surgery》2005,11(2):104-108
An 80-year-old man underwent middle and lower lobectomy of the right lung to treat squamous cell carcinoma (SCC) (4 cm in diameter) originating from the right B4 bronchus. On the 4th postoperative day, a massive air leak from the thoracic drain was noted. At that time, a diagnosis of bronchial stump fistula was made on the basis of the bronchoscopic findings. Continuous thoracic drainage, aspiration of sputum via a tracheostomy and intravenous administration of antibiotics were performed immediately after the diagnosis. However, the patient's condition was complicated by aspiration pneumonia. On the 11th postoperative day, bronchoscopic procedure to close the bronchial fistula was performed via the tracheostomy. During this procedure, metallic coils were first inserted into the fistula to serve as the core for occlusion. Then, instead of directly infusing fibrin glue, several small beans-sized pieces of Surgicell cotton (Johnson & Johnson Co., Cincinnati, OH) soaked in fluid A (concentrated fibrinogen) and the same number of Surgicell cotton pieces soaked in fluid B (thrombin) were alternately inserted into the fistula, to allow closure of the bronchial fistula. After this procedure, the embolus created remained in place without being expectorated, and the aspiration pneumonia entered remission, allowing the patient to be discharged from the hospital on the 24th postoperative day. At preset, 14 months after surgery, the patient is in good condition. This technique allows simple and reliable closure of a fistula if a tracheostomy is available. It should be selected as a therapy of first choice when dealing with patients with a postoperative bronchial stump fistula in poor general condition. Patients undergoing right pneumonectomy or middle and lower lobectomy of the right lung should be considered as belonging to a high risk group for bronchial fistula and as requiring preventable measures (e.g., covering the stump with an intercostal muscle flap). 相似文献
9.
I. Akiguchi Hidekazu Tomimoto Toshihiko Suenaga Hideaki Wakita Herbert Budka 《Acta neuropathologica》1997,95(1):78-84
Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and
lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated
in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we
describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s
disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group
I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial
fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as
extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared
to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical
U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic
vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular
WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s
disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic
cerebral ischemia or arterial hypertension.
Received: 25 April 1997 / Revised, accepted: 21 July 1997 相似文献
10.
Otagiri Masaki Yamamichi Ryuji Marayama Toru Imai Teruko Suenaga Ayaka Imamura Yorishige Kimachi Kazuhiko 《Pharmaceutical research》1989,6(2):156-159
The interactions of acidic and basic drugs with 1-acid glycoprotein (1-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to 1-AGP. The CD data suggested the presence of a single binding site on the 1-AGP molecule. The induced ellipticities of the acidic drug–1-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to 1-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with 1-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs. 相似文献