975 resultados para Clinical validation
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The primary aim of the research activity presented in this PhD thesis was the development of an innovative hardware and software solution for creating a unique tool for kinematics and electromyographic analysis of the human body in an ecological setting. For this purpose, innovative algorithms have been proposed regarding different aspects of inertial and magnetic data elaboration: magnetometer calibration and magnetic field mapping (Chapter 2), data calibration (Chapter 3) and sensor-fusion algorithm. Topics that may conflict with the confidentiality agreement between University of Bologna and NCS Lab will not be covered in this thesis. After developing and testing the wireless platform, research activities were focused on its clinical validation. The first clinical study aimed to evaluate the intra and interobserver reproducibility in order to evaluate three-dimensional humero-scapulo-thoracic kinematics in an outpatient setting (Chapter 4). A second study aimed to evaluate the effect of Latissimus Dorsi Tendon Transfer on shoulder kinematics and Latissimus Dorsi activation in humerus intra - extra rotations (Chapter 5). Results from both clinical studies have demonstrated the ability of the developed platform to enter into daily clinical practice, providing useful information for patients' rehabilitation.
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Objective: Our purpose was to present and discuss the psychiatric diagnoses of patients who presented psychogenic non-epileptic seizures (PNES) during video-electroencephalographic monitoring (VEEG). Methods: Out of 98 patients, a total of 28 patients presented PNES during the diagnostic procedure. In those cases in which the PNES that occurred during VEEG were validated by clinical history (clinical validation), and by showing the recorded event on video to an observer close to the patient (observer validation), was defined psychogenic non-epileptic seizure disorder (PNESD). Psychiatric diagnoses were made according to DSM-IV. Results: In 27, psychogenic non-epileptic seizures disorder was diagnosed. Fourteen patients presented only with psychogenic non-epileptic seizure disorder, 13 with both psychogenic non-epileptic seizures disorder and epilepsy, and one patient with epilepsy only. Psychiatric diagnoses were: 17 (63%) patients with conversion disorder, five (19%) with somatization disorder, two (7%) with dissociative disorder NOS, two (7%) with post-traumatic stress disorder and one (4%) with undifferentiated somato-form disorder. Conclusions: Dissociative-conversion non-epileptic seizures are the most frequent finding, representing the pseudoneurological manifestation of mental disorders that have these symptoms as a common feature. Provisionally, they may be defined as dissociative-conversion non-epileptic seizure disorders. (C) 2007 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.
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OBJECTIVE: To compare the immunogenicity of three yellow fever vaccines from WHO-17D and Brazilian 17DD substrains (different seed-lots). METHODS: An equivalence trial was carried out involving 1,087 adults in Rio de Janeiro. Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) were administered following standardized procedures adapted to allow blocked randomized allocation of participants to coded vaccine types (double-blind). Neutralizing yellow fever antibody titters were compared in pre- and post-immunization serum samples. Equivalence was defined as a difference of no more than five percentage points in seroconversion rates, and ratio between Geometric Mean Titters (GMT) higher than 0.67. RESULTS: Seroconversion rates were 98% or higher among subjects previously seronegative, and 90% or more of the total cohort of vaccinees, including those previously seropositive. Differences in seroconversion ranged from -0.05% to -3.02%. The intensity of the immune response was also very similar across vaccines: 14.5 to 18.6 IU/mL. GMT ratios ranged from 0.78 to 0.93. Taking the placebo group into account, the vaccines explained 93% of seroconversion. Viremia was detected in 2.7% of vaccinated subjects from Day 3 to Day 7. CONCLUSIONS: The equivalent immunogenicity of yellow fever vaccines from the 17D and 17DD substrains was demonstrated for the first time in placebo-controlled double-blind randomized trial. The study completed the clinical validation process of a new vaccine seed-lot, provided evidence for use of alternative attenuated virus substrains in vaccine production for a major manufacturer, and for the utilization of the 17DD vaccine in other countries.
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Este documento apresenta uma avaliação sobre o uso dos simuladores fisiológicos como padrão para avaliação metrológica dos esfigmomanómetros automáticos na estimação da pressão sanguínea pelo método não invasivo (PNI). O presente estudo procurou avaliar o enquadramento destes equipamentos com os procedimentos das normas e recomendações usadas para apreciação metrológica dos esfigmomanómetros digitais. No contexto da prática metrológica existente determinou-se a existência de uma oportunidade de melhoria nos processos relacionados. O trabalho procurou obter resposta a diversas questões, relacionando a medição da pressão pelo método não invasivo, com o uso dos simuladores fisiológicos, o contexto em que estes podem ser usados, as formas de simulação, as medições e os resultados, procurando a perspetiva metrológica como enquadramento. As recomendações existentes [1] [2] [3] [4] [5] [6] [7] [8], são muito claras nos procedimentos, validação e nos desvios permitidos para os monitores da tensão arterial (MTA), equipamento que permite a avaliação dos parâmetros fisiológicos do paciente, no entanto, quando se pretende avançar para outro domínio, como o do uso dos simuladores, em particular para a simulação da PNI, não existem recomendações ou normas tão claras, e não existe sobretudo um padrão de referência que imite a natureza dinâmica que caracteriza a pressão sanguínea. O trabalho procurou ainda estabelecer a ligação entre o método clássico de auscultação (o principio de determinação da PS), a técnica digital de medição e os simuladores, para uma melhor compreensão do que é a pressão sanguínea, e como relacionar a problemática da simulação e a de um padrão de referência. Neste trabalho estão ainda presentes abordagens a diversos tópicos, como as validações clínicas, acessórios, ou a metrologia e que influenciam no final os equipamentos e o contexto que se pretende avaliar. Os diversos equipamentos testados procuraram conter amostras diversificadas, quer para os MTA de uso profissional ou doméstico, assim como para os simuladores. A avaliação dos simuladores foi realizada contra um grupo de MTAs. Foi testada a influência na medição, causada pela mudança de acessórios, ou seja, nos resultados, merecendo consideração pela perspetiva metrológica. No resumo dos testes e do estudo sobre este tema, verificou-se que esta tipologia de equipamentos pode contribuir como complemento do processo de calibração típico (estático). Não constitui por si só um método alternativo, mas permitiu estimar possíveis limites de erro e desvio padrão a partir da observação dos resultados práticos, limites esses inferiores aos processos de validação clínica. Atendendo às particularidades, estimou-se como desvio aceitável um erro mais desvio padrão de 5 + 3 mmHg para o processo de simulação. Contudo considera-se ainda importante os testes adicionais em que o simulador permite, ao verificar as medidas de segurança implementadas no equipamento e a condição dos acessórios, que como verificado afetam os resultados. No entanto nem todos os simuladores se mostram adequados a este processo pelo que a qualidade da seleção do equipamento para este fim pode eventualmente reduzir ainda mais os possíveis limites.
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Urothelial bladder carcinoma (UBC) is an intricate malignancy with a variable natural history and clinical behavior. Despite developments in diagnosis/prognosis refinement and treatment modalities, the recurrence rate is high, and progression from non-muscle to muscle invasive UBC commonly leads to metastasis. Moreover, patients with muscle-invasive or extra-vesical disease often fail the standard chemotherapy treatment, and overall survival rates are poor. Thus, UBC remains a challenge in the oncology field, representing an ideal candidate for research on biomarkers that could identify patients at increased risk of recurrence, progression, and chemo-refractoriness. However, progress toward personalized medicine has been hampered by the unique genetic complexity of UBC. Recent genome-wide expression and sequencing studies have brought new insights into its molecular features, pathogenesis and clinical diversity, revealing a landscape where classical pathology is intersected by the novel and heterogeneous molecular groups. Hence, it seems plausible to postulate that only an integrated signature of prognostic/predictive biomarkers inherent in different cancer hallmarks will reach clinical validation. In this review, we have summarized ours and others' research into novel putative biomarkers of progression and chemoresistance that encompass several hallmarks of cancer: tumor neovascularization, invasion and metastasis, and energy metabolism reprogramming of the tumor microenvironment.
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INTRODUCTION & OBJECTIVES: Urothelial tumors of upper urinary tract are ranked among the most common types of cancers worldwide. The current standard therapy to prevent recurrence is intravesical Bacillus Calmetteâ Guerin (BCG) immunotherapy, but it presents several disadvantages such as BCG failure and intolerance. Another way is to use chemotherapy, which is generally better tolerated that BCG. In this case, drugs such as epirubicin, doxorubicin, paclitaxel and gemcitabine are used. Nevertheless, intravesical chemotherapy only prevents recurrence in the short-term. These failings can be partially attributed to the short residence time and low bioavailability of the drug within the upper urinary tract and the cancer cells, resulting in a need for frequent drug instillation. To avoid these problems, biodegradable ureteral stents impregnated by supercritical fluid CO2 (SCF) with each of the four anti-cancer drugs were produced. MATERIAL & METHODS: Four formulations with different concentrations of gelatin and alginate and crosslink agent were tested and bismuth was added to confer radiopaque properties to the stent. The preliminary in vivo validation studies in female domestic pigs was conducted at the University of Minho, Braga, after formal approval by the institutionâ s review board and in accordance with its internal ethical protocol for animal experiments. Paclitaxel, epirubicin, doxorubicin and gemcitabine were impregnated in the stents and the release kinetics was measured in artificial urine solution (AUS) for 9 days by UV spectroscopy in a microplate reader. The anti-tumoral effect of the developed stents in transitional cell carcinoma (TCC) and HUVEC primary cells, used as control, was evaluated. RESULTS: The in vivo validation of this second-generation of ureteral stents performed was herein demonstrated. Biodegradable ureteral stents were placed in the ureters of a female pigs, following the normal surgical procedure. The animals remained asymptomatic, with normal urine flow. The in vitro release study in AUS of the stent impregnated showed a higher release in the first 72h for the four anti-cancer drugs impregnated after this time the plateau was achieved and the stent degraded after 9 days. The direct and indirect contact of the anti-cancer biodegradable stents with the TCC and HUVEC cell lines confirm the anti-tumor effect of the stents impregnated with the four anti-cancer drugs, reducing around 75% of the viability of the TCC cell line after 72h and no killing effect in the HUVEC cells. CONCLUSIONS: The use of biodegradable ureteral stent in urology clinical practice not only reduce the stent-related symptoms but also open new treatment therapyâ s, like in urothelial tumors of upper urinary tract. Furthermore, we have demonstrated the clinical validation in vivo pig model. This study has thus shown the killing efficacy of the anti-cancer drug eluting biodegradable stents in vitro for the TCC cell line, with no toxicity observed in the control, non-cancerous cells.The direct and indirect contact of the anti-cancer biodegradable stents with the TCC and HUVEC cell lines confirm the anti-tumor effect of the stents impregnated with the four anti-cancer drugs, reducing around 75% of the viability of the TCC cell line after 72h and no killing effect in the HUVEC cells. This study has thus shown the killing efficacy of the anti-cancer drug eluting biodegradable stents in vitro for the TCC cell line, with no toxicity observed in the control, non-cancerous cells.
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Acetabular cup orientation is a key factor determining hip stability, and standard mechanical guides have shown little help in improving alignment. An in vitro study was carried out to compare the accuracy and precision of a new gravity-assisted guidance system with a standard mechanical guide. Three hundred ten cups were impacted by 5 surgeons, and the final cup orientation was measured. With the new guide, the average error in anteversion was 0.4 degrees , compared with 10.4 degrees with the standard guide and 0.3 degrees and -4.7 degrees , respectively, for abduction angles. The average time required for orienting the cups was similar for both guides. The accuracy and reproducibility obtained with the new guide were better (P < .0001). These good results would require a clinical validation.
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Drug-resistant tuberculosis (TB) threatens global TB control and is a major public health concern in several countries. We therefore developed a multiplex assay (LINE-TB/MDR) that is able to identify the most frequent mutations related to rifampicin (RMP) and isoniazid (INH) resistance. The assay is based on multiplex polymerase chain reaction, membrane hybridisation and colorimetric detection targeting of rpoB and katG genes, as well as the inhA promoter, which are all known to carry specific mutations associated with multidrug-resistant TB (MDR-TB). The assay was validated on a reference panel of 108 M. tuberculosis isolates that were characterised by the proportion method and by DNA sequencing of the targets. When comparing the performance of LINE-TB/MDR with DNA sequencing, the sensitivity, specificity and agreement were 100%, 100% and 100%, respectively, for RMP and 77.6%, 90.6% and 88.9%, respectively, for INH. Using drug sensibility testing as a reference standard, the performance of LINE-TB/MDR regarding sensitivity, specificity and agreement was 100%, 100% and 100% (95%), respectively, for RMP and 77%, 100% and 88.7% (82.2-95.1), respectively, for INH. LINE-TB/MDR was compared with GenoType MTBDRplus for 65 isolates, resulting in an agreement of 93.6% (86.7-97.5) for RIF and 87.4% (84.3-96.2) for INH. LINE-TB/MDR warrants further clinical validation and may be an affordable alternative for MDR-TB diagnosis.
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Objective This paper reviews the development and clinical validation of photodynamic diagnosis (PDD) of bladder cancer. Methods The authors reviewed the literature on the development of PDD, in particular the evidence for the clinical efficacy of hexaminolevulinate PDD in the diagnosis of bladder cancer. Results After initial work on ultraviolet cystoscopy following oral tetracycline, the focus of PDD research shifted to the use of synthetic porphyrins. First, the prodrug delta-aminolevulinic acid (ALA) was shown to cause a transient but significant accumulation of protoporphyrin IX (PpIX) in malignant or premalignant bladder tissue. Excitation by blue light leads to PpIX fluorescence (red), which distinguishes tumour from normal tissue (blue). Hexaminolevulinate (HAL, Hexvix), an ester of ALA, was then developed and has greater bioavailability and stability than the parent compound. It has been approved for clinical use in the diagnosis of bladder cancer. Clinical studies have shown that HAL PDD detects tumours, including carcinoma in situ (CIS), that are missed by conventional white-light cystoscopy. Conclusions HAL PDD is a valuable aid to the detection of bladder tumours, including CIS.
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There are at least six psychotherapeutic treatments of personality disorders having received empirical and clinical validation in terms of their efficacy. These treatments are based on different theoretical models, namely the cognitive-behavioural, psychodynamic and interpersonal models. This article briefly presents these treatments, focusing on the process of therapeutic change. It is assumed that the process of emotional activation is one of the most interesting theoretical psychotherapy ingredient in treatments of these patients. The treatments are discussed regarding this hypothesis and its clinical implications.
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As culture-based methods for the diagnosis of invasive fungal diseases (IFD) in leukemia and hematopoietic SCT patients have limited performance, non-culture methods are increasingly being used. The third European Conference on Infections in Leukemia (ECIL-3) meeting aimed at establishing evidence-based recommendations for the use of biological tests in adult patients, based on the grading system of the Infectious Diseases Society of America. The following biomarkers were investigated as screening tests: galactomannan (GM) for invasive aspergillosis (IA); β-glucan (BG) for invasive candidiasis (IC) and IA; Cryptococcus Ag for cryptococcosis; mannan (Mn) Ag/anti-mannan (A-Mn) Ab for IC, and PCR for IA. Testing for GM, Cryptococcus Ag and BG are included in the revised EORTC/MSG (European Organization for Research and Treatment of Cancer/Mycoses Study Group) consensus definitions for IFD. Strong evidence supports the use of GM in serum (A II), and Cryptococcus Ag in serum and cerebrospinal fluid (CSF) (A II). Evidence is moderate for BG detection in serum (B II), and the combined Mn/A-Mn testing in serum for hepatosplenic candidiasis (B III) and candidemia (C II). No recommendations were formulated for the use of PCR owing to a lack of standardization and clinical validation. Clinical utility of these markers for the early management of IFD should be further assessed in prospective randomized interventional studies.
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ANTECEDENTES: El aislamiento de células fetales libres o ADN fetal en sangre materna abre una ventana de posibilidades diagnósticas no invasivas para patologías monogénicas y cromosómicas, además de permitir la identificación del sexo y del RH fetal. Actualmente existen múltiples estudios que evalúan la eficacia de estos métodos, mostrando resultados costo-efectivos y de menor riesgo que el estándar de oro. Este trabajo describe la evidencia encontrada acerca del diagnóstico prenatal no invasivo luego de realizar una revisión sistemática de la literatura. OBJETIVOS: El objetivo de este estudio fue reunir la evidencia que cumpla con los criterios de búsqueda, en el tema del diagnóstico fetal no invasivo por células fetales libres en sangre materna para determinar su utilidad diagnóstica. MÉTODOS: Se realizó una revisión sistemática de la literatura con el fin de determinar si el diagnóstico prenatal no invasivo por células fetales libres en sangre materna es efectivo como método de diagnóstico. RESULTADOS: Se encontraron 5,893 artículos que cumplían con los criterios de búsqueda; 67 cumplieron los criterios de inclusión: 49.3% (33/67) correspondieron a estudios de corte transversal, 38,8% (26/67) a estudios de cohortes y el 11.9% (8/67) a estudios casos y controles. Se obtuvieron resultados de sensibilidad, especificidad y tipo de prueba. CONCLUSIÓN: En la presente revisión sistemática, se evidencia como el diagnóstico prenatal no invasivo es una técnica feasible, reproducible y sensible para el diagnóstico fetal, evitando el riesgo de un diagnóstico invasivo.
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Introducción: La escala LLANTO para dolor es una escala que hasta la fecha ha sido solo validada en población infantil española, actualmente no se conocen datos en población colombiana. Se pretende validar la escala de dolor LLANTO en pacientes neonatos y menores de 5 años, a través de su aplicación en pacientes atendidos en una de tres instituciones, además comparándola con las escalas FLACC y PIPP dependiendo de edad del paciente. Metodología: Se incluyeron niños con cualquier tipo de dolor, clasificándolos en dos grupos por edad: 1) neonatos y 2) niños entre 1 mes y 5 años de edad, que asistieron a la Fundación Cardioinfantil, Clínica Infantil Colsubsidio o al Hospital Universitario Mayor. Las escalas fueron aplicadas por dos residentes de pediatría y una enfermera especializada en el cuidado de población infantil. Para la prueba piloto se diseñó un cuestionario determinar dificultades en la aplicación de la escala LLANTO. Una vez corregidos los problemas identificados se procederá a la validación de la escala. Resultados: Se presentan los datos de la prueba piloto. Se incluyeron 8 neonatos y 8 niños entre 1 mes y 5 años, esta muestra fue obtenida en un periodo de un mes, con la encuesta se evaluó la aceptación y entendimiento de la escala LLANTO por parte de los evaluadores. La prueba piloto mostró resultados favorables en el 100% de los encuestados. Discusión: Se considera que la escala LLANTO no requiere cambios para continuar con su validación.
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Scopo: L’obiettivo del presente programma di studio è stato quello di identificare e validare nuovi possibili bersagli terapeutici per l’osteosarcoma (OS) partendo dall’analisi del chinoma umano. Risultati: L’analisi del profilo di espressione genica ottenuta su 21 campioni clinici di OS ad alto grado di malignità ha permesso di selezionare le seguenti chinasi di possibile rilevanza biologica per l’OS: AURK-A, AURK-B, CDK2, PIK3CA, PLK-1. Le chinasi selezionate sono state validate tramite RNA interference. Successivamente è stata valutata l’efficacia dei relativi inibitori specifici: VX-680 e ZM-447439 inibitori delle Aurora-chinasi, Roscovitina di CDK2 e NMS1 di PLK-1, già inclusi in studi clinici. In termini d’inibizione della crescita cellulare le linee sono risultate maggiomente sensibili ai farmaci VX-680 e NMS1. E’ stata osservata una minor sensibilità ai farmaci VX-680, ZM447439 e NMS1 nelle linee doxorubicina(DX)-resistenti (caratterizzate da elevati livelli di espressione di ABCB1), indicando questi farmaci come potenziali substrati di ABCB1. La Roscovitina, nonostante i valori di IC50 elevati, non sembrerebbe substrato di ABCB1. La validazione preclinica di VX-680 e ZM447439 è stata completata. La forte inibizione della crescita è causata da endoreduplicazione per mancata citodieresi con conseguente formazione di una popolazione iperploide e apoptosi. Inoltre, VX-680 inibisce la motilità e la capacità di formare colonie. Esperimenti di associazione farmacologica mostrano che VX-680 interagisce positivamente con tutti i chemioterapici convenzionali impiegati nel trattamento dell’OS. NMS-1 produce interazioni positive con la DX in linee cellulari DX-resistenti, probabilmente grazie all’effetto revertante esercitato su ABCB1. La Roscovitina produce interazioni positive con CDDP e DX nelle varianti resistenti, effetto probbilmente dovuto al ruolo di CDK2 nei meccanismi di riparo del DNA. Conclusioni: L’analisi in vitro dell’attività degli inibitori ha permesso di identificare VX-680 come nuovo farmaco di potenziale interesse clinico, soprattutto in virtù delle sue interazioni sinergiche con i chemioterapici di uso convenzionale nel trattamento dell’osteosarcoma.
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Ultrasound imaging is widely used in medical diagnostics as it is the fastest, least invasive, and least expensive imaging modality. However, ultrasound images are intrinsically difficult to be interpreted. In this scenario, Computer Aided Detection (CAD) systems can be used to support physicians during diagnosis providing them a second opinion. This thesis discusses efficient ultrasound processing techniques for computer aided medical diagnostics, focusing on two major topics: (i) Ultrasound Tissue Characterization (UTC), aimed at characterizing and differentiating between healthy and diseased tissue; (ii) Ultrasound Image Segmentation (UIS), aimed at detecting the boundaries of anatomical structures to automatically measure organ dimensions and compute clinically relevant functional indices. Research on UTC produced a CAD tool for Prostate Cancer detection to improve the biopsy protocol. In particular, this thesis contributes with: (i) the development of a robust classification system; (ii) the exploitation of parallel computing on GPU for real-time performance; (iii) the introduction of both an innovative Semi-Supervised Learning algorithm and a novel supervised/semi-supervised learning scheme for CAD system training that improve system performance reducing data collection effort and avoiding collected data wasting. The tool provides physicians a risk map highlighting suspect tissue areas, allowing them to perform a lesion-directed biopsy. Clinical validation demonstrated the system validity as a diagnostic support tool and its effectiveness at reducing the number of biopsy cores requested for an accurate diagnosis. For UIS the research developed a heart disease diagnostic tool based on Real-Time 3D Echocardiography. Thesis contributions to this application are: (i) the development of an automated GPU based level-set segmentation framework for 3D images; (ii) the application of this framework to the myocardium segmentation. Experimental results showed the high efficiency and flexibility of the proposed framework. Its effectiveness as a tool for quantitative analysis of 3D cardiac morphology and function was demonstrated through clinical validation.