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991.
Purpose
We describe a new rat model of biliary atresia, induced by biliary ablation with pure ethanol.Methods
A catheter was inserted and fixed in the common bile duct of male rats. Saline or pure ethanol was injected through the catheter and the animals were monitored for 8 weeks thereafter. We measured total bilirubin (T-Bil), aspartate aminotransferase (AST), alanine transaminase (ALT), and hyaluronic acid (HA) and examined liver biopsy specimens immunohistochemically for α-smooth muscle actin staining (α-SMA) and transforming growth factor-β1 (TGF-β1).Results
The ethanol injection group animals were further divided into a temporary and a persistent liver dysfunction group. In the persistent group, T-Bil, AST, ALT and HA levels were significantly higher after 8 weeks in the persistent group than in the control group and the temporary group. In the ethanol injection group, α-SMA expression was prominent in the surrounding proliferative bile ducts and portal areas. The distribution of TGF-β1 was found prominently in hepatocytes in the center of nodules and in ductular epithelial cells.Conclusions
This study characterizes the effects of ethanol-induced bile duct injury in rats, resulting in sclerosing cholangitis and its secondary effects. We believe that this experimental model will prove useful in the study of biliary atresia. 相似文献992.
Takanori Inose Tatsuya Miyazaki Shigemasa Suzuki Naritaka Tanaka Makoto Sakai Akihiko Sano Takehiko Yokobori Makoto Sohda Masanobu Nakajima Minoru Fukuchi Hiroyuki Kato Hiroyuki Kuwano 《Surgery today》2013,43(8):877-882
Purpose
Nonspecific esophageal motility disorder (NEMD) is a vague category that includes patients with poorly defined contraction abnormalities observed during esophageal manometry. This study investigated the therapeutic effects of the video-assisted thoracoscopic surgery (VATS) approach using long myotomy and fundopexy for NEMD.Methods
The VATS approach using myotomy and fundopexy was performed for 4 patients of NEMD between 2005 and 2008. A total of 4 patients with NEMD that underwent treatment at our institution were analyzed retrospectively.Results
The patients included 2 males and 2 females with a median age of 48 years (range 21–74 years). The median duration of NEMD symptoms was 58 months (range 4–108 months). Dysphagia was a primary symptom in all patients. Chest pain was a primary symptom in 3 of 4 patients (75 %). Treatment with medication was attempted before the operation. The median operative time was 344.5 min (range 210–476 min). The median time before starting oral feeding was 2.5 days (range 2–22 days). All patients achieved a significant improvement of their previous condition.Conclusions
The VATS approach using myotomy and fundopexy for NEMD is a good treatment in cases resistant to medication and balloon dilation. 相似文献993.
Hiroji Uemura Futoshi Sano Akira Nomiya Toshihiro Yamamoto Masafumi Nakamura Yasuhide Miyoshi Kenta Miki Kazumi Noguchi Shin Egawa Yukio Homma Yoshinobu Kubota 《World journal of urology》2013,31(5):1123-1128
Purpose
To explore the possibility of targeted biopsy (TBx) using transrectal ultrasound (US) with perflubutane microbubbles, we studied the findings of different cancerous tissue imaging modalities and evaluated needle biopsy in prostate cancer (PCa) using contrast-enhanced US (CEUS) in a multicenter clinical trial.Methods
Seventy-one patients undergoing prostate biopsy received intravenous injection of perflubutane microbubbles (Sonazoid®). We evaluated and compared images obtained by CEUS. The safety observation period was 2 days after contrast administration.Results
Among the 30 patients with cancer, one or more sites with findings suggestive of cancer in CEUS were detected in 23 patients (32.4%) by TBx. Although 22 patients had positive cores of cancer by systematic biopsy (SBx), 8 patients had positive cores of cancer in TBx alone (11.3%). There was a significant difference in cancer detection rate by TBx between two cohorts with PSA < 10 ng/mL (22.9%) and PSA ≥ 10 ng/mL (52.2%) (P < 0.02). Close observation of various CEUS findings with Sonazoid® enabled targeting of cancerous areas, and consequently, a significant difference (P < 0.05) in the detection rate of cancer was recognized in the transition zone (TZ): SBx; 21/120 (17.5%) and TBx; 17/55 (30.9%). The incidence of adverse events was 6.7% and that of adverse reactions was 4%.Conclusions
CEUS with Sonazoid® improved the detection rate of PCa by visualizing cancerous lesions. More detailed examination of CEUS images provided efficient characterization especially in the TZ area. TBx according to this procedure is expected to enable a lower number of biopsies and more accurate diagnosis of PCa. 相似文献994.
Akihiro Nakabayashi Naosuke Kamei Toru Sunagawa Osami Suzuki Shingo Ohkawa Akira Kodama Goki Kamei Mitsuo Ochi 《Journal of orthopaedic research》2013,31(5):754-759
The purpose of this study is to clarify the kinetics of transplanted mesenchymal stem cells (MSCs) in rat skeletal muscle injury model and the contribution of the magnetic cell delivery system to muscle injury repair. A magnetic field generator was used to apply an external magnetic force to the injury site of the tibia anterior muscle, and 1 × 106 MSCs labeled with ferucarbotran–protamine complexes, which were isolated from luciferase transgenic rats, were injected into the injury site. MSCs were injected with and without an external magnetic force (MSC M+ and MSC M? groups, respectively), and phosphate‐buffered saline was injected into injury sites as a control. In vivo bioluminescence imaging was performed immediately after the transplantation and, at 12, 24, and 72 h, and 1 and 4 weeks post‐transplantation. Also, muscle regeneration and function were histologically and electromechanically evaluated. In vivo bioluminescence imaging showed that the photon of the MSC M+ group was significantly higher than that of the MSC M? group throughout the observation period. In addition, muscle regeneration and function in the MSC M+ group was histologically and functionally better than that of the MSC M? group. The results of our study indicated that magnetic cell delivery system may be of use in directing the transplanted MSCs to the injury site to promote skeletal muscle regeneration. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 754–759, 2013 相似文献
995.
Sachiyuki Tsukada Masaki Otsuji Akira Shiozaki Asako Yamamoto Shuro Komatsu Hideya Yoshimura Hiroo Ikeda Akiho Hoshino 《International orthopaedics》2013,37(12):2451-2456
Purpose
The reduction of periosteal compression through the use of a locking plate may minimize disturbances of bone blood supply and may improve the rate of bone union. A single-centre, assessor blinded randomized controlled trial was conducted to compare the clinical effectiveness of a locking plate and a non-locking plate.Methods
A total of 52 patients with AO/OTA 44B lateral malleolar fractures were included in this study. All patients underwent surgical fixation using a lag screw and neutralization plate. An identical treatment protocol was used in all patients, with exception of plate selection. The rate of radiographic bone union, defined as the complete disappearance of fracture lines confirmed through anteroposterior, lateral, and internal oblique views was compared at three, six, and 12 months following surgery. In addition, the Medical Outcomes 36-Item Short-Form Health Survey (SF-36) score, the time required for resolution of tenderness at the fracture site and the complication rate were evaluated.Results
Twenty-three patients were randomly assigned to undergo fixation using a locking plate, and 29 patients were assigned to undergo fixation using a non-locking plate. Intention-to-treat analysis showed no difference in the radiographic bone union rate of fibula, SF-36 score, the time for resolution of tenderness at the fracture site and complication rates.Conclusion
No differences were observed in patients with AO/OTA 44B lateral malleolar fractures undergoing fixation with a locking versus non-locking neutralization plate. 相似文献996.
997.
998.
Satsuki Miyata Masashi Urabe Akira Gomi Mutsumi Nagai Takashi Yamaguchi Tomonori Tsukahara Hiroaki Mizukami Akihiro Kume Keiya Ozawa Eiju Watanabe 《Neurologia medico-chirurgica》2013,53(10):645-654
Cytosolic isocitrate dehydrogenase 1 (IDH1) with an R132H mutation in brain tumors loses its enzymatic activity for catalyzing isocitrate to α-ketoglutarate (α-KG) and acquires new activity whereby it converts α-KG to 2-hydroxyglutarate. The IDH1 mutation induces down-regulation of tricarboxylic acid cycle intermediates and up-regulation of lipid metabolism. Sterol regulatory element-binding proteins (SREBPs) regulate not only the synthesis of cholesterol and fatty acids but also acyclin-dependent kinase inhibitor p21 that halts the cell cycle at G1. Here we show that SREBPs were up-regulated in U87 human glioblastoma cells transfected with an IDH1R132H-expression plasmid. Small interfering ribonucleic acid (siRNA) for SREBP1 specifically decreased p21 messenger RNA (mRNA) levels independent of the p53 pathway. In IDH1R132H-expressing U87 cells, phosphorylation of Retinoblastoma (Rb) protein also decreased. We propose that metabolic changes induced by the IDH1 mutation enhance p21 expression via SREBP1 and inhibit phosphorylation of Rb, which slows progressionof the cell cycle and may be associated with non-aggressive features of gliomas with an IDH1 mutation. 相似文献
999.