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Purpose

The use of cortical bone trajectory (CBT) pedicle screws for circumferential interbody fusion represents a viable alternative for single-level procedure with reduced invasiveness and less tissue destruction than the traditional technique. In addition, CBT screws have a potentially stronger pullout strength because of the greater amount of cortical bone intercepted. Only few series exist evaluating clinical and radiological outcomes of CBT screws.

Methods

This is a retrospective cohort study. All patients that underwent circumferential lumbar interbody fusion with CBT screws in our institution from 2014 to 2017 were reviewed. Patient demographics, clinical outcome with visual analogue scale (VAS) and Oswestry Disability Index (ODI), radiological data such as fusion, lordosis and muscle trauma, operative blood loss, hospital stay and use of fluoroscopy were evaluated.

Results

A total of 101 patients undergoing CBT-arthrodesis for degenerative lumbo-sacral disease were reviewed. Mean procedural time was 187 min. The mean operative blood loss and X-ray dose per procedure was 383 ml and 1.60 mg cm2, respectively. The mean hospital stay was 3.47 days. The mean follow-up was 18.23 months. Mean lordosis increment at the treated level was 4.2°. When the follow-up was longer than 12 months (53% of patients), fusion was obtained in 94% of cases. Mean ODI and VAS index improved with statistical significance.

Conclusions

This is to our knowledge that the largest available study regarding CBT for circumferential arthrodesis. Results underlined the safety of this technique and the promising clinical and radiological outcomes that will need a longer follow-up.

Graphical abstract

These slides can be retrieved under Electronic Supplementary material.
  相似文献   
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Introduction

COPD is a highly prevalent but underdiagnosed disease, due to the limited availability of forced spirometry (FS) in primary care (PC). Microspirometers are inexpensive, easy-to-use devices that can measure FEV6 and FEV1/FEV6, and may help reduce underdiagnosis. The aim of this study was to validate the Piko-6 COPD screening device by demonstrating a good correlation with standard FS.

Methods

FS and Piko-6 determinations were made in 155 patients suspected of having COPD. The correlations, ROC curves, and Youden's index of both methods were compared, taking FS as the gold standard.

Results

FEV1, FVC and FEV6 correlation coefficients and FEV1/FVC and FEV1/FEV6 ratios were 0.87 (CI 0.836–0.909), 0.729 (CI 064–0.795) and 0.947 (95% CI 0.928–0.961), respectively. The ROC curve for FEV1 determined by Piko-6 achieved an area under the curve of 0.86 (95% CI: 0.78–0.92). Youden's index with a cut-off point of 0.70 for FEV1/FEV6 was 0.97.

Conclusions

Piko-6 may be useful for COPD screening in PC. Measurements obtained with this device correlate well with those determined by FS, particularly the FEV1/FEV6 ratio. This, combined with its low cost and ease of use, may contribute to reducing COPD underdiagnosis, although its exact role in the diagnostic process remains to be determined.  相似文献   
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Metastatic cells exhibit an extraordinary phenotypic plasticity, not only in adapting to unfamiliar microenvironments but also in surviving aggressive treatments and immune responses. A major source of phenotypic variability is alternative splicing (AS) of the pre-messenger RNA. This process is catalyzed by one of the most complex pieces of cellular molecular regulatory events, the spliceosome, which is composed of ribonucleoproteins and polypeptides termed spliceosome factors. With strong evidence indicating that AS affects nearly all genes encoded by the human genome, aberrant AS programs have a significant impact on cancer cell development and progression. In this review, we present insights about the genomic and epigenomic factors affecting AS, summarize the most recent findings linking aberrant AS to metastatic progression, and highlight potential prognostic and therapeutic applications.  相似文献   
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