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The underlying mechanism involved in the interaction between neutrophil elastase inhibitors and tachykinins has not been elucidated. In this study we have examined the effects of sivelestat, a neutrophil elastase inhibitor, on the in vitro responses of airways from lipopolysaccharide (LPS)-untreated or -treated guinea-pigs to substance P. Substance P (0.01-30 micromol/l) produced concentration-dependent contractions of both tracheal and bronchial ring preparations of LPS-untreated or -treated guinea-pigs. Responsiveness to substance P in these isolated airway preparations was augmented by either epithelium removal or LPS treatment. In epithelium-intact tracheal ring preparations isolated from LPS-untreated guinea-pigs, sivelestat (100 micromol/l) significantly inhibited substance P-induced contractions. The inhibitory action was markedly attenuated by pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l), and was almost undetected following removal of the epithelium. On the other hand, in bronchial ring preparations isolated from LPS-untreated guinea-pigs, sivelestat had only a very slight effect on substance P-induced contraction of the epithelium-intact preparation, whereas sivelestat greatly inhibited contraction in epithelium-removed bronchial ring preparations. In LPS-treated guinea-pigs, whether the epithelium was intact or not, sivelestat significantly inhibited the substance P-induced contraction of bronchial ring preparations. Pretreatment with L-NAME (100 micromol/l) or indomethacin (2 micromol/l) did not affect the inhibitory effect of sivelestat in bronchial ring preparations. In conclusion, epithelium removal or LPS treatment induced hyperreactivity to substance P in the guinea-pig airway. Sivelestat caused epithelium-, nitric oxide- and prostaglandin-dependent inhibition of the substance P-induced contraction of isolated guinea-pig tracheal ring preparations. In contrast, the inhibitory effect of sivelestat on substance P-induced contraction of guinea-pig bronchial ring preparations is mediated by epithelium-, nitric oxide- and prostaglandin-independent mechanisms. Sivelestat may be effective in reducing the airway hyperresponsiveness to tachykinins induced by epithelial injury as occurs in LPS-mediated inflammatory lung diseases. 相似文献
3.
Yoshiro Matsui Mizuho Ohta Kohsuke Ohno Masao Nagumo 《Journal of oral and maxillofacial surgery》2006,64(10):1540-1545
PURPOSE: This study evaluated the bone volume, height, and width that can be obtained in alveolar ridge augmentation using titanium mesh and autogenous bone particles in patients with cleft lip/palate. PATIENTS AND METHODS: Subjects were 15 patients with cleft lip/palate requiring tertiary bone graft for implant therapy. Computed tomography (CT) scans were taken before removing the mesh, from 1 to 21 months after bone grafting. Forty-three reconstructed images corresponding to the positions for implant placement were selected for this study. The percent defect filled with bone (%BONE), defined as the percentage of newly formed bone in the space created by the mesh, was measured for image analyses. In linear analyses, 4 parameters were used: increased bone height (IBH), percent increased bone height (%IBH), increased bone width (IBW), and percent increased bone width (%IBW). Factors influencing the quantitative data and the clinical courses of placed implants were also explored. RESULTS: The average %BONE was 91.1%. IBH averaged 4.4 mm, whereas %IBH averaged 88.5%. IBW averaged 4.6 mm, whereas %IBW averaged 86.4%. Little correlation was present between the quantitative data and patient age, or time interval. A significant correlation was identified between the data for span of the grafted area and %BONE (correlation coefficient value = -0.36). However, the diminishing rate was very low. No implants were lost postoperatively. CONCLUSIONS: Alveolar ridge augmentation with titanium mesh and autogenous bone particles from the anterior iliac crest has very high predictability as a preimplant procedure in patients with cleft lip/palate. 相似文献
4.
Hitoshi Matsuda Tomomi Hasegawa Takayo Maekawa Yutaka Okita 《Annals of thoracic and cardiovascular surgery》2005,11(2):132-134
A 23-year-old man was admitted for an aortic root aneurysm with mild aortic valve regurgitation (AR) and a small pressure gradient. At surgery, findings of aortic valve, one normal left posterior commissure and very rudimentary right anterior commissure, was compatible with the uni-commisural aortic valve. Aortic root replacement with valve-sparing technique was performed. Four years later no residual AR was observed. 相似文献
5.
Kiichiro Hashimoto Naohide Mori Takao Tamesa Toshimasa Okada Shigeto Kawauchi Atsunori Oga Tomoko Furuya Akira Tangoku Masaaki Oka Kohsuke Sasaki 《Modern pathology》2004,17(6):617-622
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC. 相似文献
6.
7.
Yukata Okita M.D. Shigehito Miki M.D. Yuichi Ueda M.D. Takafumi Tahata M.D. Tetsuro Sakai M.D. Katsuhiko Matsuyama M.D. Masahiko Matsumura M.D. 《Journal of cardiac surgery》1994,9(4):433-439
A 6-year-old boy was successfully operated on for double outlet ventricle, common atrioventricular canal with severe valvular regurgitation, right atrial Isomerism, L-loop ventricles, total anomalous pulmonary venous connection, and pulmonary stenosis with hypoplastic left pulmonary artery. The Interventricular rerouting from the left ventricle to the ascending aorta was performed with a spiral patch, the lnteratrlal switching was performed by a Mustard patch, the common atrioventricular orifice was partitioned and valve repair was performed, and an 18-mm valved conduit was inserted between the right ventricle and the pulmonary artery. Although the patient had a small residual ventricular septal defect and pulmonary stenosls, the patient Is alive and well. 相似文献
8.
The purpose of this study was to clarify the significance of immunohistological staining for PCNA/cyclin in human colorectal lesions. Our results: The PCNA-positive cells existed at the bottom of colonic tubuli in the normal and hyperplastic conditions. In the neoplastic lesions, however, the positive cells were existed at the relatively surface of the mucosa (chi 2: P less than 0.01) and distributed irregularly from the bottom to the top of carcinoma tissue. These results suggested that immunohistological staining for PCNA would specifically detect the cell proliferation and be beneficial for practical use and clinical application of the diagnosis of the colorectal lesions. 相似文献
9.
Tatsuo Shirota Mie Tashiro Kohsuke Ohno Akira Yamaguchi 《Journal of oral and maxillofacial surgery》2003,61(4):471-480
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results. 相似文献
10.
Mayumi Matsuta Yuko Imamura Morimasa Matsuta Saiichi Kon Kohsuke Sasaki 《The Journal of dermatology》1994,21(1):14-19
We have applied DNA flow cytometric analysis to paraffin-embedded tissue sections of primary malignant melanomas. Conventionally, flow cytometric analysis of paraffin-embedded tissue sections has been done by the method of Hedley et al. We added ultrasound treatment to the method of Hedley et al. and a lower value of coefficient of variation was shown. Furthermore, a new technique, fluorescence in situ hybridization with a chromosome-specific repetitive DNA probe, was used for the analysis of chromosomal numerical aberrations in the same paraffin-embedded tissue sections. The DNA flow cytometric analysis showed that in 8 cases six primary malignant melanomas were of the aneuploid pattern and two cases of lentigo maligna (melamona in situ) were of the diploid pattern. By fluorescence in situ hybridization, the two cases with the diploid pattern had spots/nucleus of 1.28 and 1.12, and those with the aneuploid pattern had spots/nucleus from 2.01 to 2.27. Only one nodular melanoma in an aneuploid case showed spots/nucleus of 1.71. These data indicate that fluorescence in situ hybridization with chromosome-specific repetitive DNA probes can serve as a cytogenetic tool for the analysis of interphase nuclei of solid human tumors and may be useful for the study of tumor cell heterogeneity. 相似文献