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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   
3.
OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer.  相似文献   
4.
Leukotriene B4 (LTB4) production in polymorphonuclear leucocytes (PMN) was examined in ten children with steroid-responsive nephrotic syndrome (SRNS) before, during, and after steroid administration. Comparison of LTB4 production was made in 14 children with non-inflammatory disease who were not receiving steroid therapy. No significant change was noted in PMN LTB4 biosynthesis in children with SRNS throughout any phase of the disease. Furthermore, there was no significant difference in LTB4 biosynthesis in PMN between SRNS patients before steroid therapy and patients with non-inflammatory disease. These findings suggest that inhibition of LTB4 production is not involved in the mechanism underlying steroid action in SRNS.  相似文献   
5.
Summary Forty-nine out of 54 male workers engaged in the production of an epoxy compound, t-methyl-3-phenylglycidate, showed skin symptoms in varing degrees that may be due to the skin-irritative effect of the compound. The exposed workers were also shown to have subjective symptoms which may be related to the irritative property of the compound on surface tissue. Laboratory examinations on the blood obtained from the exposed workers showed significantly higher values of leukocyte concentration as compared with the non-exposed controls. This was chiefly caused by the increase of neutrophilic granulocytes and T-cell lymphocytes. Serum IgA levels of the exposed workers were shown to be significantly lower than those of the control group. Hemoglobin concentration, hematocrit value and red cell count of the exposed workers remained at the same level as those of the control subjects. Liver or kidney damage was not found in biochemical analyses on the sera of exposed workers.  相似文献   
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Electron microscopic and immunohistochemical studies were carried out on materials obtained from three patients of gamma heavy chain disease ( λ -HCD). Electron microscopically, proliferating cells showed various stages of maturation from immunoblast to plasma cell, and the majority of proliferating cells were proplasmacytes and plasma cells. From the intracytoplasmic immunoglobulin studies by immunoperoxidase method (PAP method) and electron microscopical enzyme-labeled antibody technique, proliferating cells, such as the immunoblast, plasmablast, proplasmacyte, and plasma cell, showed positive reaction to anti- λ -heavy chain serum and anti-Fc fragment (IgG) serum, and also in a third case with Bence Jones protein, proliferating cells showed positive reaction to anti-K light chain serum. We would conclude that proliferating cells in λ -HCD might be a single clone proliferation of B-cell synthesizing λ -HCD protein, and the predominant proliferation cells are proplasmacytes and plasma cells situated near mature plasma cells in the B-cell line.  相似文献   
8.
The precise distribution and expression of Toll-like receptor (TLR) 9 in gut-associated lymphoid tissues (GALTs) has not been elucidated. In this study, we investigated the expression pattern of TLR9 in adult and neonatal swine GALTs by real-time quantitative PCR, western blot, confocal laser microscopy and flow cytometric analysis. The swine TLR9 gene was preferentially expressed in adult Peyer's patches (Pps) and mesenteric lymph nodes (MLNs), which contained approximately three times higher TLR9 than the spleen. Other tissues exhibited only weak expression of TLR9. In neonatal swine, elevated expression of TLR9 was detected only in MLNs. We firstly showed that highly expressive (TLR9(+)) cells were formed in Pps and MLNs. In addition, TLR9(+) cells were present not only in immune cells such as dendritic cells and B cells but also in follicle-associated epithelia (FAE) including membranous cells (M cells) in Pps. These results suggest that Pps and MLNs provide the host defense with the ability to respond to a variety of bioactive oligonucleotides (ODNs) from bacteria at a conductive site of initial immune responses.  相似文献   
9.
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic.  相似文献   
10.
Localization and expression of chondromodulin-I in the rat cornea   总被引:1,自引:0,他引:1  
The localization and expression in the rat cornea of chondromodulin-I (ChM-I), an inhibitory angiogenesis factor, were examined by immunohistochemistry, Western blot analysis, ribonuclease protection assay, and real-time PCR assay. We found immunoreactivity for ChM-I in the epithelial layer but not the stromal layer or endothelial layer in the cornea, in addition to the positive ChM-I immunoreactivity in other sites in the eye such as the sclera, retina, and ciliary body. The ChM-I immunoreactivity was most intense at the outside of the basal cells and in their cytoplasm while the intensity of the immunoreactivity decreased gradually from the wing cells to the superficial cells in the corneal epithelial layer. No reactivity however, was detected in the Bowman's membrane or conjunctival epithelial cells which had continuity with the corneal epithelial cells. The expression of ChM-I mRNA was demonstrated in the cornea at one-third less intensity than that in the sclera with choroids and retinal pigment epithelium by ribonuclease protection assay and real-time PCR. ChM-I in the corneal epithelial layer may prevent neovascularization and maintain avascularity in the cornea.  相似文献   
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