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91.
In vivo visualization and portally repeated transplantation of bone marrow cells in rats with liver damage 总被引:1,自引:0,他引:1
Haga J Wakabayashi G Shimazu M Tanabe M Takahara T Azuma T Sato Y Hakamata Y Kobayashi E Kitajima M 《Stem cells and development》2007,16(2):319-328
Recent reports have raised concerns over the feasibility of differentiating bone marrow cells (BMCs) into functional hepatocytes. Such augmentation is considered necessary for potential clinical use of these cells in liver diseases. The present investigation was designed to determine the kinetics of transplanted BMCs and evaluate the effects of repeated bone marrow transplantation (BMT) in rat models of CCl(4)-induced liver damage. The early kinetics of transplanted BMCs was evaluated with a charge-coupled-device (CCD) camera using BMCs obtained from green fluorescent protein (GFP) transgenic (Tg) rats and followed up with in vivo imaging system (IVIS) using BMCs obtained from firefly luciferase (luc) Tg rats. We used a portal infusion system for repeated BMT. BMCs were transplanted via a peripheral vein or the portal vein (PV) once or repeatedly using this system. The results revealed that BMCs accumulated more in the damaged liver than in the intact liver. In the experimental group receiving repeated BMT via the PV, the liver fibrosis was milder than that in the group not receiving BMT, and large clusters of albumin-producing cells were detected by albumin staining. The injected BMCs were shown to accumulate in the damaged liver. This strategy of repeated BMT has potential clinical use in enhancing the number of albumin-producing cells and suppressing liver fibrosis. This combination of beneficial effects may contribute to the benefits of cell transplantation therapy. Demonstration of the benefits of BMT in this study may be expected to have great significance for clinical trials. 相似文献
92.
93.
Ximing Zhang Takayuki Furumatsu Yuki Okazaki Takaaki Hiranaka Yuya Kodama Haowei Xue Yoshiki Okazaki Toshifumi Ozaki 《Journal of orthopaedic science》2021,26(3):430-434
BackgroundSevere chondral lesions and varus knee alignment are associated with poor outcomes following transtibial pullout repair for medial meniscus posterior root tears and meniscus tear is strongly associated with body mass index. The prognostic factors in well-aligned knees (femorotibial angle < 180°) with mild chondral lesions are unknown. Therefore, we investigated the prognostic factors in these patients. We hypothesized that high body mass index would lead to poor clinical outcomes following pullout repair of medial meniscus posterior root tears.MethodsWe retrospectively reviewed the files of 28 patients who had undergone pullout repair of medial meniscus posterior root tears between October 2016 and December 2017. We recorded the baseline characteristics (age, gender, height, weight, and body mass index) and the time between injury and surgery. We recorded the International Knee Documentation Committee scores, Knee injury and Osteoarthritis Outcome Scores, and pain visual analog scale scores. Using magnetic resonance imaging preoperatively and 1 year after surgery, we measured the medial meniscus body width and absolute and relative medial meniscus extrusion. Pearson correlation and multivariate linear regression analyses were used to assess potential associations between these factors and clinical outcomes.ResultsAge positively correlated (coefficient = 0.49, P < 0.01) and body mass index negatively correlated with the postoperative International Knee Documentation Committee score (coefficient = ?0.64, P < 0.01). In multivariate linear regression analysis, body mass index was a significant factor leading to poor postoperative International Knee Documentation Committee score (R2 = 0.29, P < 0.05).ConclusionsBody mass index > 30 kg/m2 is a risk factor for unfavorable clinical outcomes following pullout repair of medial meniscus posterior root tears in well-aligned knees.Level of evidenceIII, Comparative retrospective study. 相似文献
94.
Relationship Between Fibril Length and Tissue Ingrowth in the Healing of Expanded Polytetrafluoroethylene Grafts 总被引:1,自引:0,他引:1
Purpose To determine whether fibril length is correlated with graft healing as well as cellular and capillary ingrowth in a canine carotid implantation model.Methods Expanded polytetrafluoroethylene (ePTFE) vascular grafts with three different fibril lengths (30, 60, and 90µm) were implanted into the carotid artery in dogs. They were retrieved 4 weeks later, and subjected to histomorphometric analysis.Results Endothelial healing was best in the 60-µm grafts. Not only cellular ingrowth but also capillary ingrowth was most evident in the 60-µm grafts, followed by the 90-µm grafts and then the 30-µm grafts.Conclusion Better endothelial healing of ePTFE vascular grafts is correlated with more cellular and capillary ingrowth, but more cellular and capillary ingrowth is not correlated with longer fibril length or higher air porosity. 相似文献
95.
The aim of this study was to clarify the characteristics of pancreatic head carcinomas mainly invading the groove between
the duodenum and the pancreatic head. Nine patients with pathologically proven pancreatic head carcinomas underwent thin-slice
dynamic CT, MR imaging, duodenal endoscopy, and angiography (seven patients). Plate-like masses within the groove region were
seen in all cases, which showed hypointensity on T1-weighted images and slight hyperintensity on T2-weighted MR images. The
masses appeared hypovascular in the early phase and delayed enhancement in the late phase of dynamic CT and MR imaging. On
MR cholangiopancreatography, stenosis of intrapancreatic common bile duct was seen in all patients, whereas stenosis of the
main pancreatic duct was seen in only three cases. Endoscopy revealed luminal narrowing of the duodenum in all patients, and
duodenal mucosal biopsy demonstrated adenocarcinoma in seven patients. Abdominal arteriography showed serrated encasement
of peripancreatic arteries in seven patients who received angiographic examinations. The CT and MR imaging findings of groove
pancreatic carcinomas resemble those of groove pancreatitis. Differential diagnosis may be achieved by the pathological diagnosis
of a biopsy specimen of the duodenal mucosa and arterial encasement on arteriography. 相似文献
96.
Murakami T Ishimaru H Sakamoto I Uetani M Matsuoka Y Daikoku M Honda S Koshiishi T Fujimoto T 《Cardiovascular and interventional radiology》2007,30(4):696-704
PURPOSE: To analyze local recurrence-free rates and risk factors for recurrence following percutaneous radiofrequency ablation (RFA) or transcatheter arterial chemoembolization (TACE) for hypervascular hepatocellular carcinoma (HCC). METHODS: One hundred and nine nodules treated by RFA and 173 nodules treated by TACE were included. Hypovascular nodules were excluded from this study. Overall local recurrence-free rates of each treatment group were calculated using the Kaplan-Meier method. The independent risk factors of local recurrence and the hazard ratios were analyzed using Cox's proportional-hazards regression model. Based on the results of multivariate analyses, we classified HCC nodules into four subgroups: central nodules < or =2 cm or >2 cm and peripheral nodules < or =2 cm or >2 cm. The local recurrence-free rates of these subgroups for each treatment were also calculated. RESULTS: The overall local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p = 0.013). The 24-month local recurrence-free rates in the RFA and TACE groups were 60.0% and 48.9%, respectively. In the RFA group, the only significant risk factor for recurrence was tumor size >2 cm in greatest dimension. In the TACE group, a central location was the only significant risk factor for recurrence. In central nodules that were < or =2 cm, the local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p < 0.001). In the remaining three groups, there was no significant difference in local recurrence-free rate between the two treatment methods. CONCLUSION: A tumor diameter of >2 cm was the only independent risk factor for local recurrence in RFA treatment, and a central location was the only independent risk factor in TACE treatment. Central lesions measuring < or =2 cm should be treated by RFA. 相似文献
97.
Clinical and diagnostic significance of preoperative computed tomography findings of ascites in patients with advanced gastric cancer 总被引:5,自引:0,他引:5
Yajima K Kanda T Ohashi M Wakai T Nakagawa S Sasamoto R Hatakeyama K 《American journal of surgery》2006,192(2):185-190
BACKGROUND: The relationship between ascites, as detected by preoperative computed tomography (CT), and peritoneal metastasis of gastric cancer requires clarification because of its likely significance for clinical outcome. METHODS: A retrospective analysis of 293 patients with advanced gastric cancer investigated the association between preoperative CT findings of ascites and surgical findings of peritoneal washing cytology and peritoneal metastasis. RESULTS: Forty-five of 293 patients (15%) presented with ascites on preoperative CT. Positive ascites on CT predicted the presence of free tumor cells with 40% sensitivity and 97% specificity, and peritoneal metastasis with 51% sensitivity and 97% specificity. Ascites on CT was an independent prognostic factor by univariate (P < .001) and multivariate (relative risk, 2.03; 95% confidence interval, 1.39-2.96; P < .001) analyses. The median survival time was 6.0 months in patients with positive ascites on CT. CONCLUSIONS: The presence of ascites on CT suggests the presence of peritoneal metastasis and indicates a poor prognosis. The presence of peritoneal metastasis should be confirmed by diagnostic laparoscopy in gastric cancer patients with ascites. 相似文献
98.
Eiji Nakata Shinsuke Sugihara Masaaki Kataoka Natsumi Yamashita Takayuki Furumatsu Tomoyuki Takigawa Tomoko Tetsunaga Toshifumi Ozaki 《Journal of orthopaedic science》2018,23(6):912-917
Background
Radiation therapy (RT) is the common treatment for painful vertebral bone metastases without paralysis by malignant spinal cord compression. However, no studies have focused on the time course of pain after RT. Then, we investigated the change of pain after RT for painful vertebral bone metastases without paralysis.Methods
Participants included 101 patients who received RT for painful vertebral bone metastases without paralysis in our institution between 2012 and 2016. All patients received RT and pain response was evaluated by Numeric Rating Scale (NRS). Follow-up assessments were performed just before the start of RT and every month for six months after RT. Pain response was classified as complete response (CR), partial response (PR), pain progression (PP), and indeterminate response (IR) based on the response criteria of International Bone Metastases Consensus Working Party. Responders were classified as either CR or PR, and non-responders as either PP or IR.Results
Median NRS scores for pain were 5 before RT, decreasing to 0 by one month after RT and remaining zero until last follow-up, representing a significant decrease over time (P < 0.001). The rate of responders at each month from one to six months was 93, 96, 95, 100, 98, and 96%, respectively. Multivariate analysis revealed that Spinal Instability Neoplastic Score (SINS) was the only risk factor for response to RT at one month. At one month pain disappeared in 88% of the patients with spinal stability (SINS < 7), although pain disappeared 58% of the patients with spinal instability (SINS ≥ 7), which was significant (P = 0.002).Conclusions
Pain decreased significantly over time and 93% of patients were classified as responders as early as one month after RT in patients with painful vertebral bone metastases without paralysis. Pretreatment SINS could be a predictor of pain response to RT. 相似文献99.
Hiroaki Onuma Kunikazu Tsuji Takashi Hoshino Kei Inomata Mio Udo Yusuke Nakagawa Hiroki Katagiri Kazumasa Miyatake Toshifumi Watanabe Ichiro Sekiya Takeshi Muneta Hideyuki Koga 《Journal of orthopaedic research》2020,38(6):1296-1306
The infrapatellar fat pad (IFP) contains nerve fiber endings and is considered to play an important role in the perception of knee pain. However, it is unclear whether and to what degree prolonged pain influences the nociceptive role of the IFP. To answer this question, we established a novel rat model of knee pain in which inflammation is restricted to the IFP. Rats received a single intra-IFP injection of monoiodoacetic acid (MIA) (0.2 mg/10 µL or 1.0 mg/10 µL) in the left knee and a phosphate-buffered saline (10 µL) injection in the right knee as a control. Pain-avoidance behavior and histological changes of the knee joint were measured at multiple time points up to 28 days after MIA injection. Histological analysis showed a transient inflammatory response in the IFP body in the 0.2-mg model, whereas prolonged inflammation followed by fibrotic changes was observed in the 1.0-mg model. Subtle histological alterations were observed in the articular cartilage and IFP surface regardless of the dose. The pain-avoidance behavior test indicated the development of prolonged knee pain throughout the experimental period in the 1.0-mg group. Histological assessments showed a significant increase in calcitonin gene-related peptide (CGRP)-positive nerve fiber endings inside IFPs with fibrosis in newly vascularized surrounding regions. These data suggest that irreversible fibrotic changes in the IFP induce the formation of new vessels and CGRP-positive nerve fiber endings that associate prolonged pain in the joint. 相似文献
100.
Takayuki Furumatsu Ami Maehara Yuki Okazaki Toshifumi Ozaki 《Journal of orthopaedic science》2018,23(5):811-818