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101.
Erythropoietin protects the kidneys against ischemia reperfusion injury by activating hypoxia inducible factor-1alpha 总被引:4,自引:0,他引:4
Imamura R Moriyama T Isaka Y Namba Y Ichimaru N Takahara S Okuyama A 《Transplantation》2007,83(10):1371-1379
BACKGROUND: Ischemia/reperfusion (I/R) injury is closely associated with tissue damage in various organs, as well as in kidney transplants. Erythropoietin (EPO) has been shown to have a cytoprotective effect against hypoxia. We examined the effect of EPO against renal I/R injury and the underlying mechanism. METHODS: Human umbilical vein endothelial cells and human renal proximal tubular epithelial cells were cultured under hypoxic conditions with various EPO concentrations at 37 degrees C and examined the mechanism of cell proliferation by EPO. Moreover, to demonstrate the renoprotective effect in vivo, we treated Sprague-Dawley rats with 100 IU/kg EPO every 2 days for 2 weeks (a total of 6 doses). One day after the last injection, the operations to produce renal I/R injury (bilateral renal occlusion for 60 min) were done, and rats were killed at the end of the reperfusion period (24 hr and 72 hr after reperfusion began). RESULTS: First, we demonstrated in vitro that EPO increased hypoxia inducible factor-1alpha (HIF-1alpha) expression and stimulated proliferation of both cells under hypoxic conditions. Next, we demonstrated in vivo that EPO treatment increased the number of HIF-1alpha-positive cells, and markedly induced the expression of vascular endothelial growth factor messenger RNA. Using pimonidazole, a molecular probe that detects hypoxia, we found that EPO markedly attenuated tubular hypoxia, and reduced the number of terminal transferase dUTP nick end labeling-positive apoptotic cells and alpha-smooth muscle actin-positive interstitial cells. CONCLUSIONS: We suggested a novel HIF-1alpha induction pathway by EPO under hypoxic conditions. Thus, EPO may protect the kidneys against ischemia reperfusion injury by activating HIF-1alpha. 相似文献
102.
Tomohiro Mimura Kanji Mori Taku Kawasaki Shinji Imai Yoshitaka Matsusue 《World journal of orthopedics》2014,5(1):14-22
A wide variety of pelvic osteotomies have been developed for the treatment of developmental dysplasia of the hip (DDH). In the present paper, we present a detailed review of previous studies of triple osteotomy as an alternative treatment for DDH. We also report our experience treating 6 adult cases of DDH by triple osteotomy in order to highlight the various aspects of this procedure.The mean age of our patients was 31.2 years with a mean follow-up period of 6 years. We assessed range of motion, center-edge angle, acetabular index angle, Sharp angle, acetabulum head index, head lateralization index, Japanese Orthopedic Association score, Harris hip score, patient satisfaction, and the difference between lower limb lengths before and after the procedure. At final follow-up, clinical scores were significantly improved and radiographic parameters also showed good correction of acetabulum. 相似文献
103.
Akihiro Shimomura Isao Matsui Takayuki Hamano Takuya Ishimoto Yumiko Katou Kenji Takehana Kazunori Inoue Yasuo Kusunoki Daisuke Mori Chikako Nakano Yoshitsugu Obi Naohiko Fujii Yoshitsugu Takabatake Takayoshi Nakano Yoshiharu Tsubakihara Yoshitaka Isaka Hiromi Rakugi 《Journal of the American Society of Nephrology : JASN》2014,25(9):1954-1965
Vascular calcification (VC) is a life-threatening complication of CKD. Severe protein restriction causes a shortage of essential amino acids, and exacerbates VC in rats. Therefore, we investigated the effects of dietary l-lysine, the first-limiting amino acid of cereal grains, on VC. Male Sprague-Dawley rats at age 13 weeks were divided randomly into four groups: low-protein (LP) diet (group LP), LP diet+adenine (group Ade), LP diet+adenine+glycine (group Gly) as a control amino acid group, and LP diet+adenine+l-lysine·HCl (group Lys). At age 18 weeks, group LP had no VC, whereas groups Ade and Gly had comparable levels of severe VC. l-Lysine supplementation almost completely ameliorated VC. Physical parameters and serum creatinine, urea nitrogen, and phosphate did not differ among groups Ade, Gly, and Lys. Notably, serum calcium in group Lys was slightly but significantly higher than in groups Ade and Gly. Dietary l-lysine strongly suppressed plasma intact parathyroid hormone in adenine rats and supported a proper bone-vascular axis. The conserved orientation of the femoral apatite in group Lys also evidenced the bone-protective effects of l-lysine. Dietary l-lysine elevated plasma alanine, proline, arginine, and homoarginine but not lysine. Analyses in vitro demonstrated that alanine and proline inhibit apoptosis of cultured vascular smooth muscle cells, and that arginine and homoarginine attenuate mineral precipitations in a supersaturated calcium/phosphate solution. In conclusion, dietary supplementation of l-lysine ameliorated VC by modifying key pathways that exacerbate VC.Medial vascular calcification is common in aging, diabetes, and CKD.1–4 Because the presence of vascular calcification is strongly associated with increased cardiovascular morbidity and mortality, several studies in both animals and humans have sought ways to reduce the extent of vascular calcification.5–10 However, satisfactory therapies have not yet been established.11Adenine-induced renal failure is one of the commonly used animal models for studying the development of vascular calcification, but the prevalence of vascular calcification in this model is not very high. Indeed, Price et al. reported that vascular calcification was detected in only 30% of rats with adenine-induced chronic renal failure (adenine rats) fed a normal-protein diet.5 These authors speculated that consistent vascular calcification might require a longer period of adenine feeding. On the basis of this idea, they designed a low-protein (LP) diet in an attempt to reduce the nitrogen load and thus enable the rats to thrive on the adenine diet for longer periods. As a result of this attempt, Price et al. unexpectedly found that adenine rats fed a LP diet had extensive vascular calcification without a longer feeding period.5 All 13 adenine rats fed the LP diet had uniform alizarin red staining of the aorta, whereas only 3 of the 11 adenine rats fed a normal-protein diet had partial calcification.5 These findings indicated that dietary protein deficiency correlates with the extent of vascular calcification.Proteins are usually made from 20 kinds of amino acids. On the basis of nutritional requirements, these amino acids can be divided into two groups: essential amino acids (EAAs) and non-EAAs. Because restriction of dietary protein results in a shortage of EAAs, the level of dietary EAAs may be relevant to the extent of vascular calcification. Among nine EAAs, this study focused on l-lysine (l-Lys) based on the following three reasons. First, l-Lys is the first-limiting amino acid in most cereal grains.12 Second, the safety of l-Lys supplementation has been verified in the area of animal husbandry. l-Lys has long been added to feed grains in order to improve the utility of feed proteins.13 Third, several studies have demonstrated that dietary supplementation with l-Lys protects bones from osteoporosis, a pathologic condition that often coexists with vascular calcification.14,15 These points prompted us to hypothesize that supplementation with l-Lys would ameliorate vascular calcification. Therefore, in this study, we tested this hypothesis using adenine rats. 相似文献
104.
Hisashi Shiga Katsuya Endo Masatake Kuroha Yoichi Kakuta Seiichi Takahashi Yoshitaka Kinouchi Tooru Shimosegawa 《Surgical endoscopy》2014,28(7):2120-2128
Background
The efficacy of colorectal endoscopic submucosal dissection (ESD) has been reported mainly from Japanese referral centers. However, ESD is technically difficult and associated with a higher risk of adverse events than endoscopic mucosal resection, especially for novices performing colorectal ESD with little experience in gastric ESD. The current study evaluated the results of colorectal ESD during the clinical learning curve by retrospectively examining the results of colorectal ESD performed by four endoscopists who had experience with fewer than five cases of gastric ESD.Methods
The study retrospectively investigated the first 20 cases managed by each endoscopist, for a total of 80 cases. The main outcome measurements were procedural time, en bloc resection rate with tumor-free margins (R0 resection rate), and adverse events rate. From among clinicopathologic characteristics, factors that affected main outcome measurements were identified.Results
Of the 80 cases (56 colonic and 24 rectal lesions; 44 granular laterally spreading tumors (LSTs) and 23 nongranular LSTs, 5 depressed, and 8 protruding), 54 cases (67.5 %) had resection using a standard tip-type knife, and 26 cases (32.5 %) had resection using a small scissors-type knife. The mean tumor diameter was 34.9 ± 14.1 mm, and the mean procedural time was 108.8 ± 53.4 min. The resection in 75 cases (93.8 %) was performed en bloc, and the R0 resection rate was 75 % (60/80). Perforation occurred in six cases (7.5 %) and postoperative hemorrhage in three cases (3.8 %). Multivariate analyses showed that colonic lesions and larger lesions (≥40 mm) were significantly associated with prolonged procedural time (≥90 min). Use of the scissors-type knife was significantly associated with a higher R0 resection rate. Perforation occurred only in colonic lesions.Conclusions
For novices in colorectal ESD, beginning with rectal and smaller lesions may be advisable. Also, using scissors-type knives may increase the R0 resection rate. 相似文献105.
Masahiro Wada Alan T. Lefor Hiroyuki Mutoh Tomonori Yano Yoshikazu Hayashi Keijiro Sunada Naoyuki Nishimura Yoshimasa Miura Hiroyuki Sato Hakuei Shinhata Hironori Yamamoto Kentaro Sugano 《Surgical endoscopy》2014,28(8):2428-2436
Background
Double-balloon endoscopy (DBE) has become a new standard in enteroscopy. However, it may be difficult to make a diagnosis or plan treatment strategy with endoscopic visualization alone. The addition of endoscopic ultrasonography (EUS) has the potential to improve the ability to establish the diagnosis and develop a treatment strategy. The present study was conducted to assess the feasibility and usefulness of EUS with DBE.Methods
EUS with DBE was performed in 31 of 891 patients who underwent DBE from July 2004 to March 2011 at Jichi Medical University Hospital. We analyzed the EUS findings for lesions and evaluated the usefulness of EUS considering the following three factors: qualitative diagnostic value for lesions, depth grading of lesions, and evaluation of the structure of severe strictures prior to endoscopic balloon dilation.Results
EUS was performed for 31/32 lesions (97 %) in 31 patients. EUS findings were informative for 29/32 lesions (91 %). EUS findings were useful for establishing a qualitative diagnosis in 15/25 lesions (60 %). EUS findings for depth grading provided useful information for determining the therapeutic strategy in 11/13 lesions (85 %). EUS with DBE was useful in the evaluation of strictures for all six lesions (100 %). The overall usefulness of EUS with DBE on decision making was 72 % (23/32) in this study.Conclusions
EUS with DBE is feasible and useful. It provides additional information on small-bowel disease and contributes to establishing a precise diagnosis and selection of an appropriate therapeutic strategy. 相似文献106.
Tomoyuki Yano M.D. Mutsumi Okazaki M.D. Ph.D. Runa Kawaguchi M.D. Nobuko Suesada M.D. Kentaro Tanaka M.D. Seiji Kishimoto M.D. Ph.D. 《Microsurgery》2013,33(6):487-490
Tongue reconstruction was performed using a deep inferior epigastric perforator (DIEP) free flap in a 6‐year‐old girl with undifferentiated sarcoma of the tongue. After hemi‐glossectomy with upper neck dissection, a 3‐lobed DIEP free flap was used for the reconstruction. Donor site was closed primarily with suturing umbilicus in proper position. No flap loss, leakage, or infection occurred. Postoperatively, the patient was able to consume a normal diet without difficulty or aspiration and displayed good speech function. No donor site morbidity, e.g., herniation or bulging, was observed, and the patient was able to perform their normal daily activities. DIEP flaps provide a pliable skin paddle, an adequate amount of adipose tissue, and reduced donor site morbidity, even in children. We did not have any difficulty harvesting the DIEP flap or with the microvascular anastomosis. We consider DIEP free flaps to be the ideal option for pediatric tongue reconstruction. © 2013 Wiley Periodicals, Inc. Microsurgery 33:487–490, 2013. 相似文献
107.
Takashi Iwazawa Mitsunobu Imazato Tadashi Ohnishi Yutaka Kimura Hiroshi Yano Takushi Monden 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(8):386-389
We report adult congenital bronchoesophageal fistula with both symptomatic fistula and asymptomatic one. A 56-year-old woman
with a history of cough after drinking fluids was diagnosed as bronchoesophageal fistula by upper gastrointestinal series
that showed a diverticulum in the middle portion of the esophagus with a fistula between the esophagus and right lower lung.
Esophagoscopy revealed an orifice of the fistula located 27 cm from the incisors. Computed tomography showed chronic inflammatory
change with bronchiectasis in the S6 segment of the right lung. The patient underwent video assisted thoracic surgery that
identified two fistulae without missing a symptomatic one, and both were successfully resected. The fistulae were lined by
squamous epithelium and smooth muscle without evidence of malignancy, infection or chronic inflammation that were histologically
compatible with congenital fistulae. 相似文献
108.
Hand-assisted laparoscopic splenectomy for splenic tumors 总被引:3,自引:0,他引:3
Yano H Nakano Y Tono T Ohnishi T Iwazawa T Kimura Y Kanoh T Monden T 《Digestive surgery》2004,21(3):215-222
BACKGROUND: The feasibility of hand-assisted laparoscopic splenectomy (HALS) for splenic tumors including benign or malignant neoplasms and the associated clinical outcome of the patients remain unclear. METHODS: A total of 10 patients with splenic tumors undergoing HALS were retrospectively analyzed in this study. The intraoperative course, postoperative course, and postoperative recovery were evaluated. RESULTS: Ten patients with splenic tumors consisted of 5 with benign tumors and 5 with malignant tumors. HALS was not converted to an open splenectomy in any of the patients. Mean operative time was 170 min (range 100-310 min). Mean estimated blood loss was 105 g (range 10-900 g). Mean splenic size and splenic weight was 13 cm and 478 g, respectively. Splenomegaly based on size or weight occurred in 50% of the patients. There were no intra- or postoperative complications. Postoperative chemotherapy was given to 4 patients with malignant tumors including metastatic carcinomas and malignant lymphomas. All the patients were alive at a mean follow-up of 26 months, ranging from 15 to 43 months after surgery. There was no port-site recurrence after surgery in our study. Mean time to first flatus, mean time to first walking, mean time to resumption of oral intake, mean length of hospital stay, and mean duration of epidural analgesia were 1.8, 1, 1.5, 10.8 and 3.1 days, respectively. The results were equal in terms of intra- and postoperative course to those seen with a standard laparoscopic splenectomy for 13 patients with idiopathic thrombocytopenic purpura. CONCLUSION: HALS may be a good indication for malignant tumors as well as benign tumors of the spleen. 相似文献
109.
Takiguchi S Sekimoto M Fujiwara Y Yasuda T Yano M Hori M Murakami T Nakamura H Monden M 《Surgical endoscopy》2004,18(1):106-110
Background: Laparoscopic extended lymph node dissection for gastric cancer is difficult to perform because it requires dissection with preservation of vessels. Therefore, an intraoperative navigation system for the angioarchitecture would be helpful. Recent enhanced volume-rendering computed tomography (CT) can produce clear intraluminal three-dimensional (3D) images. This advanced radiological technology can provide 3D angiographic images reconstructed in the same view as would be observed from a laparoscope inserted into the abdominal cavity. We report our experience with laparoscopic gastrectomy with radical lymph node dissection using this advanced radiological technology. Methods: 3D CT angiographic images from the celiac axis to the proper hepatic artery were reconstructed in two ways preoperatively. The first was only 3D angiographic images that were reconstructed as the laparoscopic view (LapView 3D CT angiography). The second was LapView 3D CT angiography with images of the body of the pancreas, which was more useful for intraoperative navigation in comprehensing anatomy. Two monitors were placed over the shoulder of the patient during surgery. One monitor, which was controlled by the image mixer, projected the laparoscopic images with picture in picture of 3D CT angiographic images. The surgeon performed the surgery with reference to this monitor during lymph node dissection. Results: 3D angiographic CT clearly showed all vessels of interest in laparoscopic lymph node dissection for gastric cancer in 10 cases. The anatomy of vessels appeared as if looking beyond visible surface.
LapView 3D CT angiography was useful for laparoscopic navigation surgery.
Paper presented at the Scientific Session of the 8th World Congress of Endoscopic Surgery hosted by SAGES, New York, NY, USA, March 2002 相似文献
110.
Yoshiharu Nishimura Yoshitaka Okamura Keiichi Fujiwara Shuji Yamamoto Atsutoshi Hatada Takahiro Hisaoka 《Annals of thoracic and cardiovascular surgery》2004,10(4):259-262
A 47-year-old woman who had been diagnosed as having aortitis syndrome underwent aortic root replacement for an ascending aortic aneurysm and aortic regurgitation. Because the patient has been treated with steroids for more than 20 years, a Freestyle stentless valve was used to avoid the risk of valve detachment. There were no complications observed during the postoperative course. Although long-term follow-up will be necessary to observe the valve durability, the Freestyle stentless valve seems to be useful for aortic root replacement in patients at high risk of valve detachment due to aortitis syndrome. 相似文献