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991.
Hiromi Tateno MD PhD Ryuji Sakakibara MD PhD Shunsuke Shiina BSci Hirokazu Doi PhD Fuyuki Tateno MD PhD Mitsutoshi Sato PhD Tohru Masaka PhD Masahiko Kishi MD PhD Yohei Tsuyusaki MD Yosuke Aiba MD Tsuyoshi Ogata MSc Yasuo Suzuki MD PhD 《Journal of the American Geriatrics Society》2015,63(11):2416-2418
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Sparing Native Upper Lobes in Living‐Donor Lobar Lung Transplantation: Five Cases From a Single Center
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A. Aoyama F. Chen K. Minakata K. Yamazaki T. Yamada M. Sato H. Date 《American journal of transplantation》2015,15(12):3202-3207
Living‐donor lobar lung transplantation (LDLLT) is indicated for rapidly deteriorating patients, and the total volume of two lower lobe grafts must be sufficient for the recipient. To rescue patients with small lobar grafts, we performed five LDLLTs sparing native upper lobes. This strategy was used when upper lobes or segments were preoperatively less impaired. There were no hospital deaths. Extracorporeal circulation time and operative time were similar to those of conventional LDLLTs. The length of intensive care unit stay was also similar. Late complications attributed to the spared lungs were airway infection in one recipient and pneumothorax in two but they were successfully managed. All recipients were discharged without supplemental oxygen. The spared lung volumes measured by volumetry did not change after LDLLT. Lung perfusion scintigraphy performed at 1 year showed remaining perfusion in the spared lungs, although much less than in the grafts. These results suggested that the spared lobes kept adequate space in the thoracic cavity and kept functioning to a limited extent. The new lobar‐sparing strategy appears feasible and effective in LDLLT using small grafts for selected patients when the upper lobes or segments are less impaired. 相似文献
997.
Mitani Genya Takagaki Tomonori Hamahashi Kosuke Serigano Kenji Nakamura Yutaka Sato Masato Mochida Joji 《Journal of orthopaedic surgery and research》2015,10(1):1-6
Growth factors such as nerve growth factor (NGF) and insulin-like growth factor-1 (IGF-1) have been shown to play a role in the healing process of nerve injury. Recent researches have also shown that oxytocin administration activates these growth factors of importance for the healing of nerve tissue. The objective of the present study was to evaluate the effects of oxytocin on peripheral nerve regeneration in rats. Twenty-four male Sprague-Dawley rats were underwent transection damage model on the right sciatic nerve and defective damage model on the left sciatic nerve. The animals were assigned to one of two groups: control group or treatment group (received 80 mg/kg oxytocin intraperitoneally for 12 weeks). The sciatic nerve was examined, both functionally (on the basis of climbing platform test) and histologically (on the basis of axon count), 3, 6, 9, and 12 weeks after the injury. Also, stereomicroscopic and electrophysiological evaluations were carried out. Significantly greater improvements in electrophysiological recordings and improved functional outcome measures were presented in the treatment group at 12-week follow-up. Stereomicroscopic examinations disclosed prominent increases in vascularization on proximal cut edges in the oxytocin group in comparison with the control group. Higher axon counts were also found in this group. Intraperitoneal oxytocin administration resulted in accelerated functional, histological, and electrophysiological recovery after different sciatic injury models in rats. 相似文献
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999.
Excessive zinc intake elevates systemic blood pressure levels in normotensive rats--potential role of superoxide-induced oxidative stress 总被引:3,自引:0,他引:3
OBJECTIVES: The present study was designed to examine whether or not excessive Zn intake affects systemic blood pressure (BP) levels in a normotensive state. METHODS: Systolic BP (SBP) and mean arterial pressure (MAP) before and after administration of the nitric oxide synthase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME) or the exogenous superoxide scavenger, tempol and the activity of the endogenous superoxide scavenger, Cu/Zn-superoxide dismutase (SOD) and levels of endothelial type (e)NOS mRNA and protein in the thoracic aorta were analyzed in male Sprague-Dawley rats fed a standard diet containing 0.005% Zn or a high Zn diet containing 0.5% Zn for 8 weeks. RESULTS: SBP and MAP levels observed at the end of dietary conditioning were significantly elevated in rats fed a high Zn diet relative to rats fed a standard diet. Administration of L-NAME caused an increase in MAP levels in rats fed a standard and a high Zn diet, demonstrating the involvement of the vasodilator, nitric oxide (NO) in the regulation of systemic BP in the two groups of rats. However, the expression of eNOS mRNA and protein in the thoracic aorta was not significantly different between rats fed a standard and a high Zn diet. On the other hand, administration of tempol led to a decrease in MAP levels in rats fed a standard and a high Zn diet, indicating the participation of the oxygen free radical, superoxide in the modification of systemic BP in the two groups of rats. As reported recently, the mechanism involved is due likely to a decrease in the action of the vasodilator, NO through the formation of peroxynitrite based on the non-enzymatic reaction of superoxide and NO. In addition, tempol treatment dramatically restored MAP levels in rats fed a high Zn diet to levels comparable with those observed in rats fed a standard diet, indicating that an elevation in systemic BP levels seen in rats fed a high Zn versus a standard diet is presumably brought by a reduction in the action of the vasodilator, NO resulting from an increase in the action of superoxide. The activity of Cu/Zn-SOD in the thoracic aorta was significantly reduced in rats fed a high Zn diet relative to rats fed a standard diet, appearing to at least in part, play a role in an increase in the action of superoxide in the vessel wall of rats fed a high Zn diet. CONCLUSIONS: Excessive Zn intake may be a factor to elevate systemic BP levels in a normotensive state presumably through the oxidative stress caused by superoxide. 相似文献
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Glutathione-S-transferase P1-1 protects aberrant crypt foci from apoptosis induced by deoxycholic acid 总被引:4,自引:0,他引:4
Nobuoka A Takayama T Miyanishi K Sato T Takanashi K Hayashi T Kukitsu T Sato Y Takahashi M Okamoto T Matsunaga T Kato J Oda M Azuma T Niitsu Y 《Gastroenterology》2004,127(2):428-443
BACKGROUND & AIMS: Aberrant crypt foci, precursors of colonic adenoma, are frequently positive for glutathione-S-transferase P1-1. Because deoxycholic acid is an apoptosis-inducing xenobiotic in the colon, we examined the possibility that aberrant crypt foci, through the cytoprotecting function of glutathione-S-transferase P1-1, resist deoxycholic acid-induced apoptosis, thereby surviving to become adenomas and subsequently cancer. METHODS: Glutathione-S-transferase P1-1 or cyclooxygenase-2 expression and the percentage of apoptotic cells in aberrant crypt foci were examined by immunohistochemistry and by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, respectively. Glutathione-S-transferase P1-1 was transfected into colon cancer cells (M7609) and human lung fibroblasts, and deoxycholic acid-induced apoptosis was evaluated by a dye-uptake assay and flow cytometry. Binding of deoxycholic acid to glutathione-S-transferase P1-1 was analyzed by circular dichroism and immunoprecipitation. Caspase activities were determined by colorimetric protease assay, and sulindac binding to glutathione-S-transferase P1-1 was determined by inhibition assay of glutathione-S-transferase P1-1 activity. RESULTS: Aberrant crypt foci showed positive immunostaining for glutathione-S-transferase P1-1 but negative staining for cyclooxygenase-2. The percentage of apoptotic cells in aberrant crypt foci was significantly lower than in healthy epithelium, and the difference became more apparent with deoxycholic acid treatment. The impaired sensitivity of aberrant crypt foci to deoxycholic acid was restored by the glutathione-S-transferase P1-1-specific inhibitor gamma-glutamyl-S-(benzyl)cysteinyl-R-phenylglycine diethylester. By transfection of glutathione-S-transferase P1-1, M7609 cells became more resistant to deoxycholic acid-induced apoptosis than mock transfectants. Direct binding of glutathione-S-transferase P1-1 to deoxycholic acid was proven by circular dichroism and by immunoprecipitation. The aberrant crypt foci in adenoma patients treated with sulindac, which was shown to bind to glutathione-S-transferase P1-1, underwent apoptosis in 4 days and mostly regressed in 2-3 months. CONCLUSIONS: Glutathione-S-transferase P1-1 protects aberrant crypt foci from deoxycholic acid-induced apoptosis and may play a pivotal role in early colon carcinogenesis. 相似文献