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Background: Skeletal muscle wasting commonly occurs in patients with chronic obstructive pulmonary disease (COPD) and has been associated with the presence of systemic inflammation and endocrinological disturbance. The aim of this study is to analyze the effect of rehabilitation program on the balance of anabolic versus catabolic hormone in patients with COPD and in healthy subjects. Methods: Nineteen patients with COPD and 16 age-matched healthy subjects undertooked exercise training 3 days/week for 8 weeks. Before and after the training program the concentration of growth hormone (GH), Insulin-Like Growth Factor-1 (IGF-1), Insulin-like Growth Factor-Binding Protein 3 (IGF-BP3), testosterone and cortisol in serum were determined. The exercise measurements included a 6-Minute Walking Test (6MWT). Results: After 8 weeks, there was no significant change in lung function in patients with COPD and healthy subjects. Growth hormone, Insulin-like Growth Factor-1 and Insulin-like Growth Factor-Binding Protein 3 increased significantly after rehabilitation training (p < 0.01). The rehabilitation program improves the testosterone/cortisol ratio (T/C ratio) in both groups. There is a significant improvement in the 6-Minute Walking distance (6MWD) in both groups (p < 0.01). Dyspnea and heart rate at rest and at the peak of the 6-Minute Walking Test (6MWT) decreased significantly after training program (p < 0.01). Conclusion: Pulmonary rehabilitation induces an improvement of the anabolic process and reduces proteine distruction by the modifications in endocrinological factors regulating skeletal muscle in patients with COPD.  相似文献   
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Summary

Diaphysis, inferior, and lateral superior regions of the femoral neck are subjected to diverse mechanical loads. Using micro-CT based on synchrotron radiation, three-dimensional morphology and connectivity of the pore network are location dependent, underlying different remodeling mechanisms.

Introduction

The three-dimensional (3D) morphology and connectivity of the pore network at various locations in human femurs subjected to diverse mechanical loads were assessed using micro-CT based on synchrotron radiation.

Methods

The cortex from 20 human femurs (mean age, 78.3?±?12.4 years) was taken from the diaphysis (D), the inferior (IN), and the lateral superior (LS) regions of the femoral neck. The voxel size of the 3D reconstructed image was 7.5 μm. Cortical thickness and pore volume/tissue volume (Po.V/TV), pore diameter (Po.Dm) and spacing (Po.Sp) were determined. The pore surface/pore volume ratio (Po.S/Po.V), the number of pores (Po.N), the degrees of anisotropy (DA), and the connectivity density (ConnD), the degree of mineralization (DMB) were also determined.

Results

The characteristics of the pore network in femoral cortical bone were found to be location dependent. There was greater porosity, Po.Dm, and Po.N, and more large (180–270 μm), extra-large (270–360 μm) and giant pores (>360 μm) in the LS compared to the IN and D. The difference in porosity in between the periosteal and endosteal layers was mostly due to an increase of Po.Dm rather than Po.N. There was a lower DMB of bone in the LS, which is consistent with a higher remodeling rate.

Conclusion

The results provide evidence for large variations in the structure of the internal pore network in cortical bone. These variations could involve different underlying remodeling mechanisms.  相似文献   
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Introduction

Lymph node dissection (LND) has been advocated by oncologic surgeons to completely eradicate cancer. However, evidence for that strategy is solely based on poor quality data. Some randomized studies done outside the field of urology failed to show any benefit to LND. Our objective was to evaluate whether LND at the time of removal of prostate, kidney and urothelial carcinomas results in a survival benefit.

Methods

For that purpose, we performed a systematic literature review.

Results

For kidney cancer, LND might be able to cure some patients with N+ disease. In N0 patients, although a randomized trial has been completed, the value of LND remains uncertain. LND at the time of radical prostatectomy can be useful in some patients with lymph node invasion. However, studies on the impact of LND in pN0 patients are retrospective and conflictive. Extended LND has been recommended when performing a radical cystectomy based on improved outcomes observed in retrospective studies. However, these studies are limited by selection biases and results of ongoing randomized trials will specify the template and the advantages of LND when removing a bladder cancer. Recent data of large series of radical nephro-ureterectomies for upper tract urothelial carcinomas are conflicting. Some found a benefit of LND in N0 patients while others did not.

Conclusion

The studies that support LND at the time of surgery for prostate, kidney and urothelial carcinomas have low level of evidence. This should encourage urologists to design and perform well-designed randomized trials to assess the potential survival impact of a commonly done procedure.  相似文献   
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Objectives

The role of topical upper urinary tract instillation as adjuvant treatment after conservative management of urothelial carcinomas remains unclear. The aim of this article was to review available techniques and protocols proposed to treat urothelial carcinomas of the upper tract (UTUC).

Methods

Evidence acquisition on UTUC topical instillations was performed by a Medline search using combinations of the following key words: urothelial carcinomas; upper urinary tract; renal pelvis; ureter; adjuvant therapy; recurrence; bacillus Calmette-Guérin (BCG); mitomycin C. A total of 36 publications were included in analysis.

Results

Different approaches have been reported for instillation of the upper tract (UT): percutaneous nephrostomy, retrograde catheterisation and vesico-ureteral reflux. Currently, BCG and mitomycin C are the most commonly agents used for topical treatment of UTUC. A role for BCG in the management of UT carcinoma in situ (CIS) has been demonstrated in retrospective studies, although a definitive efficacy of adjuvant topical therapy after endoscopic resection of Ta/T1 tumours has not yet been proven. No individual study has shown a statistical improvement in survival and recurrence rates.

Conclusion

Currently BCG instillation should be considered as first-line treatment for UT CIS managed conservatively in carefully selected patients. The place for adjuvant topical instillation after ablation of Ta/T1 tumours is less evident and should be evaluated on an individual basis.  相似文献   
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Background

Excision repair cross-complementing 1 (ERCC1) has been associated with outcomes of urothelial carcinoma of the bladder, but was not yet studied in upper tract urothelial carcinoma (UTUC). The aim of this study was to assess the prognostic role of ERCC1 expression in a large international cohort of UTUC patients.

Methods

Immunohistochemical ERCC1 expression was evaluated in 716 UTUC patients who underwent radical nephroureterectomy with curative intent. ERCC1 was considered positive when the H-score was >1.0. Associations with overall survival and cancer-specific survival were assessed using univariable and multivariable Cox models.

Results

ERCC1 was expressed in 303 tumors (42.3 %) and linked with the presence of tumor necrosis (16.2 vs. 10.4 %, p = 0.023), but not with any other clinical or pathological variable. ERCC1 status did not predict cancer-specific survival and overall survival on both univariable (p = 0.70 and 0.32, respectively) and multivariable analyses (p = 0.48 and 0.33, respectively).

Conclusions

ERCC1 is expressed in a significant proportion of UTUC and is linked with tumor necrosis, but its expression appears not to be associated with prognosis following radical nephroureterectomy.
  相似文献   
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