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Gonzalez-Castano D.M.,University of Santiago de Compostela | Gonzalez L.B.,General Universitario Of Valencia | Gago-Arias M.A.,University of Santiago de Compostela | Pardo-Montero J.,University of Santiago de Compostela | And 4 more authors.
Medical Physics | Year: 2012

Purpose: This work contains an alternative methodology for obtaining correction factors for ionization chamber (IC) dosimetry of small fields and composite fields such as IMRT. The method is based on the convolution/ superposition (C/S) of an IC response function (RF) with the dose distribution in a certain plane which includes chamber position. This method is an alternative to the full Monte Carlo (MC) approach that has been used previously by many authors for the same objective. Methods: The readout of an IC at a point inside a phantom irradiated by a certain beam can be obtained as the convolution of the dose spatial distribution caused by the beam and the IC two-dimensional RF. The proposed methodology has been applied successfully to predict the response of a PTW 30013 IC when measuring different nonreference fields, namely: output factors of 6 MV small fields, beam profiles of cobalt 60 narrow fields and 6 MV radiosurgery segments. The two-dimensional RF of a PTW 30013 IC was obtained by MC simulation of the absorbed dose to cavity air when the IC was scanned by a 0.6 × 0.6 mm 2 cross section parallel pencil beam at low depth in a water phantom. For each of the cases studied, the results of the IC direct measurement were compared with the corresponding obtained by the C/S method. Results: For all of the cases studied, the agreement between the IC direct measurement and the IC calculated response was excellent (better than 1.5). Conclusions: This method could be implemented in TPS in order to calculate dosimetry correction factors when an experimental IMRT treatment verification with in-phantom ionization chamber is performed. The miss-response of the IC due to the nonreference conditions could be quickly corrected by this method rather than employing MC derived correction factors. This method can be considered as an alternative to the plan-class associated correction factors proposed recently as part of an IAEA work group on nonstandard field dosimetry. © 2012 American Association of Physicists in Medicine. Source

Noguera J.F.,General Universitario Of Valencia | Dolz C.,Hospital Son Llatzer | Cuadrado A.,Hospital Son Llatzer | Olea J.,Hospital Son Llatzer | Garcia J.,Hospital Son Llatzer
Surgical Innovation | Year: 2013

Introduction. The development of natural orifice transluminal endoscopic surgery has led to other techniques, such as single-incision surgery. The use of the flexible endoscope for single-incision surgery paves the way for further refinement of both surgical methods. Objective. To describe a new, single-incision surgical technique, namely, flexible single-incision surgery. Patients and Methods. Assessment of the safety and effectiveness of endoscopic cholecystectomy in a series of 30 patients. This technique consists of a single umbilical incision through which a flexible endoscope is introduced and consists of 2 parallel entry ports that provide access to nonarticulated laparoscopic instruments. Results. The technique was applied in all patients for whom it was prescribed. No general or surgical wound complications were noted. Surgical time was no longer than usual for single-port surgery. Conclusions. Flexible single-incision surgery is a new single-site surgical technique offering the same level of patient safety, with additional advantages for the surgeon at minimal cost. © The Author(s) 2012. Source

De Toro-Peinado I.,Hospital Regional Universitario Of Malaga | Concepcion Mediavilla-Gradolph M.,Hospital Regional Universitario Of Malaga | Tormo-Palop N.,General Universitario Of Valencia | Palop-Borras B.,Hospital Regional Universitario Of Malaga
Enfermedades Infecciosas y Microbiologia Clinica | Year: 2015

Urinary tract infections (UTI) are the most common infectious diseases observed in primary care; up to one-third of women will have at least one symptomatic UTI by age 24, and more than one-half of women will be affected by the end of life. In addition, UTIs represent 40% of nosocomial infections, and being usually associated with urinary catheters. Although urine cultures would not be indicated in all cases, these samples are the most abundant in the laboratories of clinical microbiology. Thus, the working protocols applied to these samples have an important impact in the performance of the laboratory. The samples are collected by mid stream urine, and 60-70% of them are negative culture. At present, several commercial systems have been introduced in order to simplify and automate this process. A urine culture with ≥ 105 CFU/ml has classically been considered as positive, although lower counts are valued in certain clinical settings. Factors related to this count e.g. methods to obtain urine, conservation of the sample or use of chemical preservatives as well as low counts are critical points to be discussed in detail. The development of antimicrobial resistance logically affects uropathogens, mainly Escherichia coli, which remains the most frequently isolated in urine cultures. The aim of this paper is to review the most innovating aspects influencing the microbiological diagnosis of UTI. © 2015 Elsevier España, S.L.U. All rights reserved. Source

Arevalo J.F.,Wilmer Eye Institute | Arevalo J.F.,Stellenbosch University | Lasave A.F.,Clinica Oftalmologica Centro Caracas | Wu L.,Institute Cirugia Ocular | And 4 more authors.
Retina | Year: 2013

PURPOSE:: To evaluate the anatomical and functional outcomes at 24 months in patients with diffuse diabetic macular edema treated with primary intravitreal bevacizumab (IVB) plus grid laser photocoagulation (GLP) or primary IVB alone or GLP alone. METHODS:: Retrospective, interventional, comparative, multicenter study. We included in this analysis 141 eyes of 120 patients with diffuse diabetic macular edema treated with primary IVB alone (Group A), 120 eyes of 94 patients with GLP therapy (Group B), and 157 eyes of 104 patients treated with IVB plus GLP (Group C). RESULTS:: In all 3 groups, the authors observed improvement of Early Treatment Diabetic Retinopathy Study best-corrected visual acuity from baseline to 24-month follow-up (P < 0.0001). The improvement rate in Group A was statistically significantly better than in Group B (analysis of variance, P = 0.013). The authors also found a decrease in central macular thickness in all groups from baseline to the 24-month follow-up (P < 0.0001). The comparison among 3 groups showed higher central macular thickness decrease in Group A than in Groups B and C (analysis of variance, P < 0.001). CONCLUSION:: The study provides evidence to support the use of primary IVB with or without GLP as treatment of diffuse diabetic macular edema. Primary IVB without GLP seems to be superior to GLP alone to provide stability or improvement in best-corrected visual acuity in patients with diffuse diabetic macular edema at 24 months. Source

Uso M.,General Universitario Of Valencia | Uso M.,University of Valencia | Jantus-Lewintre E.,General Universitario Of Valencia | Jantus-Lewintre E.,Polytechnic University of Valencia | And 4 more authors.
Future Oncology | Year: 2014

Lung cancer is the leading cause of cancer death worldwide. Therefore, advances in the diagnosis and treatment of the disease are urgently needed. miRNAs are a family of small, noncoding RNAs that regulate gene expression at the transcriptional level. miRNAs have been reported to be deregulated and to play a critical role in different types of cancer, including lung cancer. Thus, miRNA profiling in lung cancer patients has become the core of several investigations. To this end, the development of a multitude of platforms for miRNA profiling analysis has been essential. This article focuses on the different technologies available for assessing miRNAs and the most important results obtained to date in lung cancer. © 2014 Future Medicine Ltd. Source

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