Flexible bronchoscopic management of benign tracheal stenosis: long term follow-up of 115 patients

<p>Abstract</p> <p>Background</p> <p>Management of benign tracheal stenosis (BTS) varies with the type and extent of the disease and influenced by the patient's age and general health status, hence we sought to investigate the long-term outcome of patients with BTS that underwent minimally invasive bronchoscopic treatment.</p> <p>Methods</p> <p>Patients with symptomatic BTS were treated with flexible bronchoscopy therapeutic modalities that included the following: balloon dilatation, laser photo-resection, self-expanding metal stent placement, and High-dose rate endobronchial brachytherapy used in cases of refractory stent-related granulation tissue formation.</p> <p>Results</p> <p>A total of 115 patients with BTS and various cardiac and respiratory co-morbidities with a mean age of 61 (range 40-88) were treated between January 2001 and January 2009. The underlining etiologies for BTS were post - endotracheal intubation (N = 76) post-tracheostomy (N = 30), Wegener's granulomatosis (N = 2), sarcoidosis (N = 2), amyloidosis (N = 2) and idiopathic BTS (N = 3). The modalities used were: balloon dilatation and laser treatment (N = 98). Stent was placed in 33 patients of whom 28 also underwent brachytherapy. Complications were minor and mostly included granulation tissue formation. The overall success rate was 87%. Over a median follow-up of 51 months (range 10-100 months), 30 patients (26%) died, mostly due to exacerbation of their underlying conditions.</p> <p>Conclusions</p> <p>BTS in elderly patients with co-morbidities can be safely and effectively treated by flexible bronchoscopic treatment modalities. The use of HDR brachytherapy to treat granulation tissue formation following successful airway restoration is promising.</p

On the nature and impact of self-similarity in real-time systems

In real-time systems with highly variable task execution times simplistic task models are insufficient to accurately model and to analyze the system. Variability can be tackled using distributions rather than a single value, but the proper charac- terization depends on the degree of variability. Self-similarity is one of the deep- est kinds of variability. It characterizes the fact that a workload is not only highly variable, but it is also bursty on many time-scales. This paper identifies in which situations this source of indeterminism can appear in a real-time system: the com- bination of variability in task inter-arrival times and execution times. Although self- similarity is not a claim for all systems with variable execution times, it is not unusual in some applications with real-time requirements, like video processing, networking and gaming. The paper shows how to properly model and to analyze self-similar task sets and how improper modeling can mask deadline misses. 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Balance of90Sr over Antarctica: Existence of a protected area

International audienceThe study of firn cores from Terre Adélie and from stations located along the axis Mirny-Vostok made possible new calculations of90Sr accumulation in Antarctica, i.e. 25.103 Ci as of January 1964. Despite the scarcity of sampling stations, an inhomogeneous geographical distribution may be observed which shows the existence of a low contamination area. Moreover, a linear relationship seems to exist in many cores between90Sr and water accumulations. Thus it could be possible to extrapolate some geochemical measurements made in Antarctica to the rest of the Southern Hemisphere

Numerical cloud model to interpret the isotope content of hailstones

SIGLEAvailable from CEN Saclay, Service de Documentation, 91191 Gif-sur-Yvette Cedex (France) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Postoperative radiotherapy in non-small-cell lung cancer: Systematic review and meta-analysis of individual patient data from nine randomised controlled trials

Background: The role of postoperative radiotherapy in treatment of patients with completely resected non-small-cell lung cancer (NSCLC) remains unclear. We undertook a systematic review and meta-analysis of the available evidence from randomised trials. Methods: Updated data were obtained on individual patients from all available randomised trials of postoperative radiotherapy versus surgery alone. Data on 2128 patients from nine randomised trials (published and unpublished) were analysed by intention to treat. There were 707 deaths among 1056 patients assigned postoperative radiotherapy and 661 among 1072 assigned surgery alone. Median follow-up was 3.9 years (2.3-9.8 for individual trials) for surviving patients. Findings: The results show a significant adverse effect of postoperative radiotherapy on survival (hazard ratio 1.21 [95% CI 1.08-1.34]). This 21% relative increase in the risk of death is equivalent to an absolute detriment of 7% (3-11) at 2 years, reducing overall survival from 55% to 48%. Subgroup analyses suggest that this adverse effect was greatest for patients with stage I/II, N0-N1 disease, whereas for those with stage III, N2 disease there was no clear evidence of an adverse effect. Interpretation: Postoperative radiotherapy is detrimental to patients with early-stage completely resected NSCLC and should not be used routinely for such patients. The role of postoperative radiotherapy in the treatment of N2 tumours is not clear and may warrant further research.SCOPUS: ar.jinfo:eu-repo/semantics/publishe