37 research outputs found

    Automated lumen segmentation using multi-frame convolutional neural networks in Intravascular Ultrasound datasets

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    Aims: Assessment of minimum lumen areas in intravascular ultrasound (IVUS) pullbacks is time-consuming and demands adequately trained personnel. In this work, we introduce a novel and fully automated pipeline to segment the lumen boundary in IVUS datasets. Methods and results First, an automated gating is applied to select end-diastolic frames and bypass saw-tooth artefacts. Second, within a machine learning (ML) environment, we automatically segment the lumen boundary using a multi-frame (MF) convolutional neural network (MFCNN). Finally, we use the theory of Gaussian processes (GPs) to regress the final lumen boundary. The dataset consisted of 85 IVUS pullbacks (52 patients). The dataset was partitioned at the pullback-level using 73 pullbacks for training (20 586 frames), 6 pullbacks for validation (1692 frames), and 6 for testing (1692 frames). The degree of overlapping, between the ground truth and ML contours, median (interquartile range, IQR) systematically increased from 0.896 (0.874–0.933) for MF1 to 0.925 (0.911–0.948) for MF11. The median (IQR) of the distance error was also reduced from 3.83 (2.94–4.98)% for MF1 to 3.02 (2.25–3.95)% for MF11-GP. The corresponding median (IQR) in the lumen area error remained between 5.49 (2.50–10.50)% for MF1 and 5.12 (2.15–9.00)% for MF11-GP. The dispersion in the relative distance and area errors consistently decreased as we increased the number of frames, and also when the GP regressor was coupled to the MFCNN output. Conclusion: These results demonstrate that the proposed ML approach is suitable to effectively segment the lumen boundary in IVUS scans, reducing the burden of costly and time-consuming manual delineation.Fil: Ziemer, Paulo G. P.. Laboratorio Nacional de Computacao Cientifica; BrasilFil: Bulant, Carlos Alberto. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Grupo de Plasmas Densos Magnetizados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; ArgentinaFil: Orlando, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Grupo de Plasmas Densos Magnetizados. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Grupo de Plasmas Densos Magnetizados; ArgentinaFil: Maso Talou, Gonzalo D.. University of Auckland; Nueva ZelandaFil: Mansilla Álvarez, Luis A.. Laboratorio Nacional de Computacao Cientifica; BrasilFil: Guedes Bezerra, Cristiano. Universidade de Sao Paulo; BrasilFil: Lemos, Pedro A.. Universidade de Sao Paulo; BrasilFil: García García, Héctor M.. Georgetown University School of Medicine; Estados UnidosFil: Blanco, Pablo J.. Laboratorio Nacional de Computacao Cientifica; Brasi

    Overactive bladder-18 years - Part II

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    Traditionally, the treatment of overactive bladder syndrome has been based on the use of oral medications with the purpose of reestablishing the detrusor stability. The recent better understanding of the urothelial physiology fostered conceptual changes, and the oral anticholinergics - pillars of the overactive bladder pharmacotherapy - started to be not only recognized for their properties of inhibiting the detrusor contractile activity, but also their action on the bladder afference, and therefore, on the reduction of the symptoms that constitute the syndrome. Beta-adrenergic agonists, which were recently added to the list of drugs for the treatment of overactive bladder, still wait for a definitive positioning - as either a second-line therapy or an adjuvant to oral anticholinergics. Conservative treatment failure, whether due to unsatisfactory results or the presence of adverse side effects, define it as refractory overactive bladder. In this context, the intravesical injection of botulinum toxin type A emerged as an effective option for the existing gap between the primary measures and more complex procedures such as bladder augmentation. Sacral neuromodulation, described three decades ago, had its indication reinforced in this overactive bladder era. Likewise, the electric stimulation of the tibial nerve is now a minimally invasive alternative to treat those with refractory overactive bladder. The results of the systematic literature review on the oral pharmacological treatment and the treatment of refractory overactive bladder gave rise to this second part of the review article Overactive Bladder - 18 years, prepared during the 1st Latin-American Consultation on Overactive Bladder.Univ Fed Sao Paulo, EPM, Sao Paulo, SP, BrazilUniv Sao Paulo, Dept Urol, BR-05508 Sao Paulo, SP, BrazilFac Med ABC, Dept Urol, Sao Paulo, SP, BrazilUniv Los Andes, Dept Urol, Bogota, ColombiaEscuela Med Mil, Dept Urol, Mexico City, DF, MexicoHosp Clin Jose San Martin, Catedra Urol, Buenos Aires, DF, ArgentinaMae de Deus Ctr Hosp, Dept Urol, Porto Alegre, RS, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilAC Camargo Hosp, Dept Urol, Sao Paulo, SP, BrazilHosp Clinico Fuerza Area Chile, Santiago, ChileInst Mexicano Seguro Social, Mexico City, DF, MexicoHosp Souza Aguiar, Dept Urol, Rio De Janeiro, RJ, BrazilComplejo Med Policial Churruca Visca, Serv Urol, Buenos Aires, DF, ArgentinaCtr Policlin Valencia Vina, Valencia, VenezuelaHosp Pablo Tobon Uribe, Medellin, ColombiaClin Indisa, Serv Urol, Providencia, ChileCtr Reabilitacao & Readaptacao Dr Henriqe Santill, Goiania, Go, BrazilHosp Univ Caracas, Serv Urol, Caracas, VenezuelaUniv Fed Ceara, Div Urol, Fortaleza, Ceara, BrazilUniv Fed Sao Paulo, EPM, Sao Paulo, SP, BrazilWeb of Scienc

    Overactive bladder-18 years - Part I

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    Overactive bladder syndrome is one of the lower urinary tract dysfunctions with the highest number of scientific publications over the past two decades. This shows the growing interest in better understanding this syndrome, which gathers symptoms of urinary urgency and increased daytime and nighttime voiding frequency, with or without urinary incontinence and results in a negative impact on the quality of life of approximately one out of six individuals - including both genders and almost all age groups. The possibility of establishing the diagnosis just from clinical data made patients' access to specialized care easier. Physiotherapy resources have been incorporated into the urological daily practice. A number of more selective antimuscarinic drugs with consequent lower adverse event rates were released. Recently, a new class of oral drugs, beta-adrenergic agonists has become part of the armamentarium for Overactive Bladder. Botulinum toxin injections in the bladder and sacral neuromodulation are routine modalities of treatment for refractory cases. During the 1st Latin-American Consultation on Overactive Bladder, a comprehensive review of the literature related to the evolution of the concept, epidemiology, diagnosis, and management was conducted. This text corresponds to the first part of the review Overactive Bladder 18-years.Univ Fed Sao Paulo, EPM, Rua Dr Oscar Monteiro Barros 617-141, BR-05641010 Sao Paulo, SP, BrazilUniv Sao Paulo, Dept Urol, BR-05508 Sao Paulo, SP, BrazilFac Med ABC, Dept Urol, Sao Paulo, SP, BrazilUniv Los Andes, Dept Urol, Bogota, ColombiaEscuela Med, Dept Urol, Mexico City, DF, MexicoHosp Clin Jose San Martin, Catedra Urol, Buenos Aires, DF, ArgentinaMae de Deus Ctr Hosp, Dept Urol, Porto Alegre, RS, BrazilUniv Fed Ciencias Saude Porto Alegre, Porto Alegre, RS, BrazilAC Camargo Hosp, Dept Urol, Sao Paulo, BrazilHosp Clin Fuerza Area Chile, Santiago, ChileInst Mexicano Seguro Social, Mexico City, DF, MexicoHosp Souza Aguiar, Dept Urol, Rio De Janeiro, RJ, BrazilComplejo Med Policial Churruca Visca, Serv Urol, Buenos Aires, DF, ArgentinaCtr Policlin Valencia Vina, Valencia, VenezuelaHosp Pablo Tobon Uribe, Medellin, ColombiaClin Indisa, Serv Urol, Providencia, ChileCtr Reabilitacao & Readaptacao Dr Henriqe Santill, Goiania, Go, BrazilHosp Univ Caracas, Serv Urol, Caracas, VenezuelaUniv Fed Ceara, Div Urol, Fortaleza, Ceara, BrazilUniv Fed Sao Paulo, EPM, Rua Dr Oscar Monteiro Barros 617-141, BR-05641010 Sao Paulo, SP, BrazilWeb of Scienc

    Overactive bladder – 18 years – Part II

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    WUE and CO<sub>2</sub> Estimations by Eddy Covariance and Remote Sensing in Different Tropical Biomes

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    The analysis of gross primary production (GPP) is crucial to better understand CO2 exchanges between terrestrial ecosystems and the atmosphere, while the quantification of water-use efficiency (WUE) allows for the estimation of the compensation between carbon gained and water lost by the ecosystem. Understanding these dynamics is essential to better comprehend the responses of environments to ongoing climatic changes. The objective of the present study was to analyze, through AMERIFLUX and LBA network measurements, the variability of GPP and WUE in four distinct tropical biomes in Brazil: Pantanal, Amazonia, Caatinga and Cerrado (savanna). Furthermore, data measured by eddy covariance systems were used to assess remotely sensed GPP products (MOD17). We found a distinct seasonality of meteorological variables and energy fluxes with different latent heat controls regarding available energy in each site. Remotely sensed GPP was satisfactorily related with observed data, despite weak correlations in interannual estimates and consistent overestimations and underestimations during certain months. WUE was strongly dependent on water availability, with values of 0.95 gC kg−1 H2O (5.79 gC kg−1 H2O) in the wetter (drier) sites. These values reveal new thresholds that had not been previously reported in the literature. Our findings have crucial implications for ecosystem management and the design of climate policies regarding the conservation of tropical biomes, since WUE is expected to change in the ongoing climate change scenario that indicates an increase in frequency and severity of dry periods

    Diretrizes para prevenção e tratamento da osteoporose induzida por glicocorticoide Guidelines for the prevention and treatment of glucocorticoid-induced osteoporosis

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    Os glicocorticoides (GC) são prescritos por praticamente todas as especialidades médicas, e cerca de 0,5% da população geral do Reino Unido utiliza esses medicamentos. Com o aumento da sobrevida dos pacientes com doenças reumatológicas, a morbidade secundária ao uso dessa medicação representa um aspecto importante que deve ser considerado no manejo de nossos pacientes. As incidências de fraturas vertebrais e não vertebrais são elevadas, variando de 30%-50% em pessoas que usam GC por mais de três meses. Assim, a osteoporose e as fraturas por fragilidade devem ser prevenidas e tratadas em todos os pacientes que iniciarão ou que já estejam em uso desses esteroides. Diversas recomendações elaboradas por várias sociedades internacionais têm sido descritas na literatura, porém não há consenso entre elas. Recentemente, o Americam College of Rheumatology publicou novas recomendações, porém elas são fundamentadas na FRAX (WHO Fracture Risk Assessment Tool) para analisar o risco de cada indivíduo e, dessa maneira, não podem ser completamente utilizadas pela população brasileira. Dessa forma, a Comissão de Osteoporose e Doenças Osteometabólicas da Sociedade Brasileira de Reumatologia, em conjunto com a Associação Médica Brasileira e a Associação Brasileira de Medicina Física e Reabilitação, implementou as diretrizes brasileiras de osteoporose induzida por glicocorticoide (OPIG), baseando-se na melhor evidência científica disponível e/ou experiência de experts. DESCRIÇÃO DO MÉTODO DE COLETA DE EVIDÊNCIA: A revisão bibliográfica de artigos científicos desta diretriz foi realizada na base de dados MEDLINE. A busca de evidência partiu de cenários clínicos reais, e utilizou as seguintes palavras-chave (MeSH terms): Osteoporosis, Osteoporosis/chemically induced*= (Glucocorticoids= Adrenal Cortex Hormones, Steroids), Glucocorticoids, Glucocorticoids/administration and dosage, Glucocorticoids/therapeutic use, Glucocorticoids/adverse effects, Prednisone/adverse effects, Dose-Response Relationship, Drug, Bone Density/drug effects, Bone Density Conservation Agents/pharmacological action, Osteoporosis/ prevention&control, Calcium, Vitamin D, Vitamin D deficiency, Calcitriol, Receptors, Calcitriol; 1-hydroxycholecalciferol, Hydroxycholecalciferols, 25-Hydroxyvitamin D3 1-alpha-hydroxylase OR Steroid Hydroxylases, Prevention and Control, Spinal fractures/prevention & control, Fractures, Spontaneous, Lumbar Vertebrae/injuries, Lifestyle, Alcohol Drinking, Smoking OR tobacco use disorder, Movement, Resistance Training, Exercise Therapy, Bone density OR Bone and Bones, Dual-Energy X-Ray Absorptiometry OR Absorptiometry Photon OR DXA, Densitometry, Radiography, (Diphosphonates Alendronate OR Risedronate Pamidronate OR propanolamines OR Ibandronate OR Zoledronic acid, Teriparatide OR PTH 1-34, Men AND premenopause, pregnancy, pregnancy outcome maternal, fetus, lactation, breast-feeding, teratogens, Children (6-12 anos), adolescence (13-18 anos). GRAU DE RECOMENDAÇÃO E FORÇA DE EVIDÊNCIA: A) Estudos experimentais e observacionais de melhor consistência; B) Estudos experimentais e observacionais de menor consistência; C) Relatos de casos (estudos não controlados); D) Opinião desprovida de avaliação crítica, com base em consensos, estudos fisiológicos ou modelos animais. OBJETIVO: Estabelecer as diretrizes para a prevenção e o tratamento da OPIG.<br>Glucocorticoids (GC) are used in almost all medical specialties, and approximately 0.5% of the general population of the United Kingdom receives those medications. With the increased survival of patients with rheumatological diseases, morbidity secondary to the use of those medications represents an important aspect of the management of our patients. The incidences of vertebral and non-vertebral fractures are elevated, ranging from 30% to 50% of the individuals on GC for over three months. Thus, osteoporosis and frailty fractures should be prevented and treated in all patients initiating or already on GC. There are several recommendations on this topic elaborated by several international societies, but consensus still lacks. Recently, the American College of Rheumatology has published new recommendations, but they are based on the WHO Fracture Risk Assessment Tool (FRAX®) to evaluate the risk for each individual, and, thus, cannot be completely used for the Brazilian population. Thus, the Committee for Osteoporosis and Bone Metabolic Disorders of the Brazilian Society of Rheumatology, along with the Brazilian Medical Association and the Brazilian Association of Physical Medicine and Rehabilitation, has elaborated the Brazilian Guidelines for Glucocorticoid-Induced Osteoporosis (GIO), based on the better available scientific evidence and/or expert experience. METHOD OF EVIDENCE COLLECTION: The bibliographic review of scientific articles of this guideline was performed in the MEDLINE database. The search for evidence was based on real clinical scenarios, and used the following keywords (MeSH terms): Osteoporosis, Osteoporosis/ chemically induced*= (Glucocorticoids= Adrenal Cortex Hormones, Steroids), Glucocorticoids, Glucocorticoids/administration and dosage, Glucocorticoids/therapeutic use, Glucocorticoids/adverse effects, Prednisone/adverse effects, Dose-Response Relationship, Drug, Bone Density/drug effects, Bone Density Conservation Agents/pharmacological action, Osteoporosis/prevention & control, Calcium, Vitamin D, Vitamin D deficiency, Calcitriol, Receptors, Calcitriol; 1-hydroxycholecalciferol, Hydroxycholecalciferols, 25-Hydroxyvitamin D3 1-alpha-hydroxylase OR Steroid Hydroxylases, Prevention and Control, Spinal fractures/prevention & control, Fractures, Spontaneous, Lumbar Vertebrae/injuries, Lifestyle, Alcohol Drinking, Smoking OR tobacco use disorder, Movement, Resistance Training, Exercise Therapy, Bone density OR Bone and Bones, Dual-Energy X-Ray Absorptiometry OR Absorptiometry Photon OR DXA, Densitometry, Radiography, (Diphosphonates Alendronate OR Risedronate Pamidronate OR propanolamines OR Ibandronate OR Zoledronic acid, Teriparatide OR PTH 1-34, Men AND premenopause, pregnancy, pregnancy outcome maternal, fetus, lactation, breast-feeding, teratogens, Children (6-12 years), adolescence (13-18 years). GRADE OF RECOMMENDATION AND LEVEL OF EVIDENCE: A) Data derived from more consistent experimental and observational studies; B) Data derived from less consistent experimental and observational studies; C) Case reports (uncontrolled studies); D) Expert opinion without explicit critical appraisal, or based on consensus, physiological studies or animal models. OBJECTIVE: To establish guidelines for the prevention and treatment of GIO
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