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71.
AIM:To investigate a dual labeling technique,which would enable real-time monitoring of transplanted embryonic stem cell(ESC) kinetics,as well as long-term tracking.METHODS:Liver damage was induced in C57/BL6 male mice(n = 40) by acetaminophen(APAP) 300 mg/kg administered intraperitoneally.Green fluorescence protein(GFP) positive C57/BL6 mouse ESCs were stained with the near-infrared fluorescent lipophilic tracer 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide(DiR) immediately before transplantationinto the spleen.Each of the animals in the cell therapy group(n = 20) received 5 × 10 6 ESCs 4 h following treatment with APAP.The control group(n = 20) received the vehicle only.The distribution and dynamics of the cells were monitored in real-time with the IVIS Lumina-2 at 30 min post transplantation,then at 3,12,24,48 and 72 h,and after one and 2 wk.Immunohistochemical examination of liver tissue was used to identify expression of GFP and albumin.Plasma alanine aminotransferase(ALT) was measured as an indication of liver damage.RESULTS:DiR-stained ESCs were easily tracked with the IVIS using the indocyanine green filter due to its high background passband with minimal background autofluorescence.The transplanted cells were confined inside the spleen at 30 min post-transplantation,gradually moved into the splenic vein,and were detectable in parts of the liver at the 3 h time-point.Within 24 h of transplantation,homing of almost 90% of cells was confirmed in the liver.On day three,however,the DiR signal started to fade out,and ex vivo IVIS imaging of different organs allowed signal detection at time-points when the signal could not be detected by in vivo imaging,and confirmed that the highest photon emission was in the liver(P 0.0001).At 2 wk,the DiRsignal was no longer detectable in vivo ;however,immunohistochemistry analysis of constitutively-expressed GFP was used to provide an insight into the distribution of the cells.GFP +ve cells were detected in tissue sections resembling hepatocytes and were dispersed throughout the hepatic parenchyma,with the presence of a larger number of GFP +ve cells incorporated within the sinusoidal endothelial lining.Very faint albumin expression was detected in the transplanted GFP +ve cells at 72 h;however at 2 wk,few cells that were positive for GFP were also strongly positive for albumin.There was a significant improvement in serum levels of ALT,albumin and bilirubin in both groups at 2 wk when compared with the 72 h time-point.In the cell therapy group,serum ALT was significantly(P = 0.016) lower and albumin(P = 0.009) was significantly higher when compared with the control group at the 2 wk time-point;however there was no difference in mortality between the two groups.CONCLUSION:Dual labeling is an easy to use and cheap method for longitudinal monitoring of distribution,survival and engraftment of transplanted cells,and could be used for cell therapy models.  相似文献   
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Purpose

Prognostic impact of lymphadenectomy during radical nephroureterectomy (RNU) for urothelial carcinoma of the upper urinary tract (UTUC) is controversial. Our aim was to assess the impact of lymph node status (LNS) on survival in patients treated by RNU.

Methods

In our multi-institutional, retrospective database, 714 patients with non-metastatic UTUC had undergone RNU between 1995 and 2010. LNS was tested as prognostic factor for survivals through univariate and multivariable Cox regression analysis.

Results

Median age was 70 years [interquartile range (IQR), 60–75] with median follow-up of 27 months (IQR, 10–50). Overall, lymphadenectomy was performed in 254 patients (35.5 %). Among these patients, 204 (80 %) had negative lymph nodes (pN0) and 50 (20 %) had positive lymph nodes (pN1/2). The 5-year cancer-specific survival (CSS) was 81 % [95 % confidence interval (CI), 73–88 %] for pN0 patients, 85 % (95 % CI, 80–90 %) for pNx patients and 47 % (95 % CI, 24–69 %) for pN1/2 patients (p < 0.001). Metastasis-free survival (MFS) and overall survival (OS) rates were significantly lower in pN1/2 patients than in pN0 and pNx patients (p < 0.05). On multivariable analysis, LNS did not appear as an independent prognostic factor for CSS, OS or MFS (p > 0.05). In case of lymph node involvement, extra-nodal extension was marginally associated with worse CSS (log rank p = 0.07). The retrospective design was the main limitation.

Conclusion

LNS is helpful for survival stratification in patients treated with RNU for UTUC. However, LNS did not appear as an independent predictor of survival in this retrospective series and needs to be investigated in a large multicentre, prospective evaluation.  相似文献   
75.
To assess the in vitro effect of platelet‐rich plasma (PRP) on biological activity of the human rotator cuff fibroblasts and to describe the optimal dose‐response to maximize cellular stimulation while reducing potential risk. Rotator cuff (RC) fibroblasts of n = 6 patients (mean age of 65.2 years) undergoing arthroscopic cuff tear reconstruction were cultured in vitro for 21 days and stimulated with PRP in three different concentrations (1‐, 5‐, and 10‐fold). Samples were obtained for DNA and GAG measurement at 1, 7, 14, and 21 days. The biological outcomes were regressed on the PRP concentration. The application of PRP significantly influenced the fibroblast proliferation and activity of the human rotator cuff with elevated glycosaminoglycan (GAG) and DNA levels. The dosage of PRP had the significantly highest impact on this proliferation using a onefold or fivefold application. PRP has a significant effect on fibroblast proliferation of the human rotator cuff in vitro with an optimal benefit using a onefold or fivefold PRP concentration. This study justifies further in vivo investigations using PRP at the human rotator cuff. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1249–1253, 2013  相似文献   
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77.

Purpose

Posterior cruciate ligament (PCL) injury has a reported incidence of 3–20 %. PCL reconstruction is aimed at reducing onset of premature articular degeneration and improving function. Numerous operative techniques have been described with varying degrees of result consistency.

Methods

We evaluated 15 patients treated for isolated primary posterior cruciate ligament injury with a mean follow-up of 4.1 years (range one to nine). Post-reconstruction clinical assessment included the Lysholm and Tegner knee scoring scale, international knee documentation committee (IKDC) ligament evaluation, and KT2000 arthrometer assessment.

Results

On the Lysholm knee score 11 patients (73 %) had excellent results, three patients (20 %) had good results and one patient (7 %) had a poor result. On the Tegner activity score the majority of patients scored 7–8 with a return to high level sports. At the final follow-up, the post-reconstruction IKDC score was normal or nearly normal (A and B) in 14 (93 %) patients, and abnormal (C) in one (7 %) patient. According to KT-2000 arthrometer measurements at final follow-up review, 11 patients (73 %) were rated as normal (A, 0–2 mm), and four patients (27 %) as nearly normal (B, 3–5 mm). These results were independent of age, mechanism of injury, time elapsed to surgical reconstruction, and length of follow-up.

Conclusions

Despite being a technically demanding procedure, the outcomes reported in this study show that single bundle transtibial arthroscopic PCL repair using four strands hamstring autograft provides satisfactory and consistent functional outcomes.  相似文献   
78.

Background

Anaplastic thyroid carcinoma (ATC) is the most aggressive form of thyroid cancer and it has an extremely poor prognosis. Rapid airway compromise is the main cause of death in patients with ATC.

Methods

The present study is based on a retrospective review of clinical data of patients with ATC treated over the last decade in a tertiary referral center.

Results

Between January 1998 and December 2010, 31 patients (13 males: 18 females) with a mean age of 74 years (range: 54–90 years) had a diagnosis of ATC made on fine-needle aspiration (n = 29) or biopsy (n = 2). Eight patients underwent total thyroidectomy and lymph node dissection, and five patients had attempted surgery but the procedure was abandoned because of inoperability. Airway compromise was clinically apparent in 11 patients. Five patients had tracheal stents inserted, with a median survival of 2 months (range: 1–36 months). In the whole cohort, 29 patients died of the disease, with a mean survival of 7 months (range: 1–36 months).

Conclusions

Survival of patients with undifferentiated thyroid cancer is severely compromised by airway obstruction. Palliation with tracheal stenting can rescue catastrophic airway obstruction but offers minimal survival benefit.  相似文献   
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The extrusion of the coil complex outside of the aneurysmal dome is thought to be an important mechanism by which the aneurysm neck and fundus recanalize, but the migration of the coil loops and their incorporation inside vital nervous structures has not been clearly described. We reviewed the medical literature on coil extrusion and migration and report a rare case of third nerve palsy due to direct damage caused by coil loop migration that resolved after surgery. A 25-year-old woman presented with subarachnoid hemorrhage and painful left third nerve palsy. The angiogram revealed a supraclinoid internal carotid aneurysm incorporating the origin of the left posterior communicating artery. Her aneurysm was coiled. The 8 month follow-up angiogram revealed a major recurrence of her aneurysm. It was decided to surgically clip the aneurysm. At surgery, coil loops were found in the subarachnoid space and embedded into the third nerve. At 1 month follow-up she had recovered well, and only had very subtle diplopia upon fatigue. Coil extrusion is a fairly common phenomenon that should be suspected in instances of major aneurysmal recurrence. Surgical treatment is recommended, and special care should be taken when mobilizing the extruded coil mass.  相似文献   
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