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1.
Radiologia (Engl Ed) ; 64 Suppl 1: 20-27, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35428463

RESUMO

OBJECTIVE: To compare the diagnostic performance of breast ultrasound and breast magnetic resonance imaging and to correlate the findings on the two techniques that are suggestive of implant rupture. MATERIAL AND METHODS: We reviewed the images and reports of breast ultrasound and magnetic resonance imaging studies done in our diagnostic and interventional breast imaging unit to evaluate breast implants in 205 patients between January 2015 and December 2017. RESULTS: Ultrasound findings were compatible with implant rupture in 87 (42.4%) patients: intracapsular rupture in 44 (21.5%) and intracapsular and extracapsular rupture in 43 (21.0%). Ultrasound yielded 85.2% sensitivity, 89.7% specificity, 86.2% positive predictive value, and 89.0% negative predictive value. Magnetic resonance imaging findings were compatible with implant rupture in 88 (42.9%) patients: intracapsular rupture in 50 (24.4%) and intracapsular and extracapsular rupture in 38 (18.5%). The correlation between positive findings for the location of the rupture on the two imaging techniques was excellent (0.77; p < 0.0001). CONCLUSION: We found high concordance between the two techniques for the detection of intracapsular and extracapsular implant rupture. These results consolidate the use of ultrasound as the first-line imaging technique to evaluate implant integrity in our population; magnetic resonance imaging can be reserved for cases in which the ultrasound diagnosis of implant integrity is uncertain.


Assuntos
Implantes de Mama , Mama , Implantes de Mama/efeitos adversos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Falha de Prótese , Ruptura , Ultrassonografia Mamária
2.
PLoS One ; 16(6): e0252148, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086705

RESUMO

OBJECTIVE: One of the main problems of lung transplantation is the shortage of organs as well as reduced survival rates. In the absence of an international standardized model for lung donor-recipient allocation, we set out to develop such a model based on the characteristics of past experiences with lung donors and recipients with the aim of improving the outcomes of the entire transplantation process. METHODS: This was a retrospective analysis of 404 lung transplants carried out at the Reina Sofía University Hospital (Córdoba, Spain) over 23 years. We analyzed various clinical variables obtained via our experience of clinical practice in the donation and transplantation process. These were used to create various classification models, including classical statistical methods and also incorporating newer machine-learning approaches. RESULTS: The proposed model represents a powerful tool for donor-recipient matching, which in this current work, exceeded the capacity of classical statistical methods. The variables that predicted an increase in the probability of survival were: higher pre-transplant and post-transplant functional vital capacity (FVC), lower pre-transplant carbon dioxide (PCO2) pressure, lower donor mechanical ventilation, and shorter ischemia time. The variables that negatively influenced transplant survival were low forced expiratory volume in the first second (FEV1) pre-transplant, lower arterial oxygen pressure (PaO2)/fraction of inspired oxygen (FiO2) ratio, bilobar transplant, elderly recipient and donor, donor-recipient graft disproportion requiring a surgical reduction (Tailor), type of combined transplant, need for cardiopulmonary bypass during the surgery, death of the donor due to head trauma, hospitalization status before surgery, and female and male recipient donor sex. CONCLUSIONS: These results show the difficulty of the problem which required the introduction of other variables into the analysis. The combination of classical statistical methods and machine learning can support decision-making about the compatibility between donors and recipients. This helps to facilitate reliable prediction and to optimize the grafts for transplantation, thereby improving the transplanted patient survival rate.


Assuntos
Transplante de Pulmão/métodos , Obtenção de Tecidos e Órgãos/métodos , Feminino , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Espanha , Taxa de Sobrevida , Doadores de Tecidos , Transplantados
3.
Radiologia (Engl Ed) ; 2021 Jan 19.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33483142

RESUMO

OBJECTIVE: To compare the diagnostic performance of breast ultrasound and breast magnetic resonance imaging and to correlate the findings on the two techniques that are suggestive of implant rupture. MATERIAL AND METHODS: We reviewed the images and reports of breast ultrasound and magnetic resonance imaging studies done in our diagnostic and interventional breast imaging unit to evaluate breast implants in 205 patients between January 2015 and December 2017. RESULTS: Ultrasound findings were compatible with implant rupture in 87 (42.4%) patients: intracapsular rupture in 44 (21.5%) and intracapsular and extracapsular rupture in 43 (21.0%). Ultrasound yielded 85.2% sensitivity, 89.7% specificity, 86.2% positive predictive value, and 89.0% negative predictive value. Magnetic resonance imaging findings were compatible with implant rupture in 88 (42.9%) patients: intracapsular rupture in 50 (24.4%) and intracapsular and extracapsular rupture in 38 (18.5%). The correlation between positive findings for the location of the rupture on the two imaging techniques was excellent (0.77; p<0.0001). CONCLUSION: We found high concordance between the two techniques for the detection of intracapsular and extracapsular implant rupture. These results consolidate the use of ultrasound as the first-line imaging technique to evaluate implant integrity in our population; magnetic resonance imaging can be reserved for cases in which the ultrasound diagnosis of implant integrity is uncertain.

4.
Neural Netw ; 123: 401-411, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31926464

RESUMO

In Machine Learning, the most common way to address a given problem is to optimize an error measure by training a single model to solve the desired task. However, sometimes it is possible to exploit latent information from other related tasks to improve the performance of the main one, resulting in a learning paradigm known as Multi-Task Learning (MTL). In this context, the high computational capacity of deep neural networks (DNN) can be combined with the improved generalization performance of MTL, by designing independent output layers for every task and including a shared representation for them. In this paper we exploit this theoretical framework on a problem related to Wind Power Ramps Events (WPREs) prediction in wind farms. Wind energy is one of the fastest growing industries in the world, with potential global spreading and deep penetration in developed and developing countries. One of the main issues with the majority of renewable energy resources is their intrinsic intermittency, which makes it difficult to increase the penetration of these technologies into the energetic mix. In this case, we focus on the specific problem of WPREs prediction, which deeply affect the wind speed and power prediction, and they are also related to different turbines damages. Specifically, we exploit the fact that WPREs are spatially-related events, in such a way that predicting the occurrence of WPREs in different wind farms can be taken as related tasks, even when the wind farms are far away from each other. We propose a DNN-MTL architecture, receiving inputs from all the wind farms at the same time to predict WPREs simultaneously in each of the farms locations. The architecture includes some shared layers to learn a common representation for the information from all the wind farms, and it also includes some specification layers, which refine the representation to match the specific characteristics of each location. Finally we modified the Adam optimization algorithm for dealing with imbalanced data, adding costs which are updated dynamically depending on the worst classified class. We compare the proposal against a baseline approach based on building three different independent models (one for each wind farm considered), and against a state-of-the-art reservoir computing approach. The DNN-MTL proposal achieves very good performance in WPREs prediction, obtaining a good balance for all the classes included in the problem (negative ramp, no ramp and positive ramp).


Assuntos
Aprendizado Profundo , Fontes Geradoras de Energia , Vento
5.
Neural Netw ; 84: 57-66, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27639724

RESUMO

Ordinal classification considers those classification problems where the labels of the variable to predict follow a given order. Naturally, labelled data is scarce or difficult to obtain in this type of problems because, in many cases, ordinal labels are given by a user or expert (e.g. in recommendation systems). Firstly, this paper develops a new strategy for ordinal classification where both labelled and unlabelled data are used in the model construction step (a scheme which is referred to as semi-supervised learning). More specifically, the ordinal version of kernel discriminant learning is extended for this setting considering the neighbourhood information of unlabelled data, which is proposed to be computed in the feature space induced by the kernel function. Secondly, a new method for semi-supervised kernel learning is devised in the context of ordinal classification, which is combined with our developed classification strategy to optimise the kernel parameters. The experiments conducted compare 6 different approaches for semi-supervised learning in the context of ordinal classification in a battery of 30 datasets, showing (1) the good synergy of the ordinal version of discriminant analysis and the use of unlabelled data and (2) the advantage of computing distances in the feature space induced by the kernel function.


Assuntos
Análise Discriminante , Análise Espacial , Aprendizado de Máquina Supervisionado , Algoritmos
6.
Dermatol Online J ; 20(3)2014 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-24656281

RESUMO

This document provides a summary of the Dutch S3-guidelines on the treatment of psoriasis. These guidelines were finalized in December 2011 and contain unique chapters on the treatment of psoriasis of the face and flexures, childhood psoriasis as well as the patient's perspective on treatment. They also cover the topical treatment of psoriasis, photo(chemo)therapy, conventional systemic therapy and biological therapy.


Assuntos
Psoríase/terapia , Adulto , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Produtos Biológicos/uso terapêutico , Criança , Terapia Combinada , Contraindicações , Vias de Administração de Medicamentos , Esquema de Medicação , Interações Medicamentosas , Quimioterapia Combinada , Humanos , Imunossupressores/uso terapêutico , Países Baixos , Aceitação pelo Paciente de Cuidados de Saúde , Psoríase/tratamento farmacológico , Psoríase/radioterapia , Retinoides/uso terapêutico , Terapia Ultravioleta/efeitos adversos , Terapia Ultravioleta/economia
7.
Acta Ortop Mex ; 27(2): 128-32, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24701766

RESUMO

The total shoulder prosthesis in reverse was designed as a treatment for patients with arthropathy deficiency rotator cuff because the conservative treatment failed. The indications for its use have evolved; these include arthropathy deficient rotator cuff, reconstruction humeral head fractures, hemiarthroplasties revision and reconstruction after tumor resection. Successful placement depends on the patient having a function adequately and good quality deltoid in the glenoid bone and in the proximal humerus. Until a few years ago data was no clear on the success of this procedure, currently encouraging results have been reported, however, they have had a high cost due to the high rate of complications, which are divided into specific and common to the prosthesis shoulder surgeries. The primary objective of this review is to assess the most common complications of the prosthesis in reverse, how to treat them and how we can avoid them.


Assuntos
Artroplastia/métodos , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Articulação do Ombro/cirurgia , Parafusos Ósseos , Remoção de Dispositivo , Humanos , Instabilidade Articular/etiologia , Instabilidade Articular/prevenção & controle , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Falha de Prótese/etiologia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/prevenção & controle , Resultado do Tratamento
8.
Neural Netw ; 24(7): 779-84, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21463924

RESUMO

This paper proposes a radial basis function neural network (RBFNN), called the q-Gaussian RBFNN, that reproduces different radial basis functions (RBFs) by means of a real parameter q. The architecture, weights and node topology are learnt through a hybrid algorithm (HA). In order to test the overall performance, an experimental study with sixteen data sets taken from the UCI repository is presented. The q-Gaussian RBFNN was compared to RBFNNs with Gaussian, Cauchy and inverse multiquadratic RBFs in the hidden layer and to other probabilistic classifiers, including different RBFNN design methods, support vector machines (SVMs), a sparse classifier (sparse multinomial logistic regression, SMLR) and a non-sparse classifier (regularized multinomial logistic regression, RMLR). The results show that the q-Gaussian model can be considered very competitive with the other classification methods.


Assuntos
Algoritmos , Redes Neurais de Computação , Distribuição Normal , Inteligência Artificial
9.
Parasitology ; 122(Pt 4): 465-70, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11315180

RESUMO

The community structure of monogeneans on the gills of a catfish Pimelodus albicans, in the Río de la Plata, was studied and compared with previous findings on P. maulatus. Six Monogenea species belonging to 3 genera were found: Demidospermus majusculus Kritsky & Gutiérrez, 1998; Demidospermus armostus Kritsky & Gutiérrez, 1998; Demidospermus idolus Kritsky & Gutiérrez, 1998; Demidospermus bidiverticulatum (Suriano & Incorvaia, 1995) Kritsky & Gutiérrez, 1998; Scleroductus yuncensi Jara & Cone, 1989; and Unibarra paranoplatensis Suriano & Incorvaia, 1995. The relationships between selected host and helminth variables; the interactions between the worms and the patterns obtained from the species abundance were analysed employing appropriate statistical methodology. The results obtained revealed the following common patterns within the monogenean communities of P. maculatus and P. albicans: (a) most monogenean species belonged to the genus Demidospermus; (b) S. yuncensi was a secondary species in both communities; (c) 1 of the 3 species common to both hosts was a core species (D. bidiverticulatum); (d) the selected variables of both hosts (weight and length) were not related to the number of monogeneans or species richness; (e) the dominant species in both communities showed the highest proportion of monogeneans in more than 40% of the infracommunities; (f) in both communities the dominant species accounted for 40-80% of the total number of monogeneans at component community level; (g) the number of worms correlates positively with the species richness; (h) few cases of interaction among species were found; (i) a high degree of order exists among the infracommunities compared. Finally, the proportion of common species and the phylogenetic and ecological resemblances between the hosts, P. maceulatus and P. albicans support a hypothesis of co-speciation among monogeneans and pimelodids in Río de la Plata. It seems improbable that these parasite communities are recent species assemblages formed by chance. The phylogenetic resemblance of the host-monogeneans system in Río de la Plata suggests that there is a single community pattern that can be observed in congeneric and sympatric hosts.


Assuntos
Peixes-Gato/parasitologia , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Trematódeos/crescimento & desenvolvimento , Infecções por Trematódeos/veterinária , Animais , Argentina , Peixes-Gato/classificação , Ecossistema , Interações Hospedeiro-Parasita , Trematódeos/classificação , Infecções por Trematódeos/parasitologia
10.
J Parasitol ; 87(2): 392-4, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11318570

RESUMO

The monotypic Philureter n. gen. (Ancyrocephalinae; Dactylogyridae) is proposed to accommodate Philureter trigoniopsis n. sp. with the following features: presence of a cuplike ventral haptor armed with 14 hooks and 2 anchor/bar complexes; dorsal pair of anchors poorly defined and variable in shape, 1 frequently absent; tandem, intercecal gonads, testis bilaterally lobulated. Philureter trigoniopsis n. sp. is described from the ureters and urinary bladder of Galaxias maculatus (Jenyns, 1842) (Osmeriformes) in Patagonian Andean lakes, Argentina.


Assuntos
Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Platelmintos/classificação , Ureter/parasitologia , Bexiga Urinária/parasitologia , Animais , Argentina/epidemiologia , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Doenças dos Peixes/epidemiologia , Peixes , Platelmintos/anatomia & histologia , Platelmintos/isolamento & purificação
11.
Parasitology ; 119 ( Pt 2): 177-82, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10466125

RESUMO

The Monogenea fauna was studied from the gills of the catfish Pimelodus maculatus. Fish were caught from Río de la Plata, in Buenos Aires harbour (Argentina). Five species of Monogenea were found. The structure of the monogenean community was analysed at the component and infracommunity level. The nature of the monogenean community, its possible interactivity, seasonal variation and predictability are also discussed.


Assuntos
Peixes-Gato/parasitologia , Brânquias/parasitologia , Trematódeos/classificação , Animais , Argentina , Interações Hospedeiro-Parasita , Estações do Ano
12.
Parasitology ; 119 ( Pt 2): 183-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10466126

RESUMO

Five Monogenea species were found on the gills of the catfish Pimelodus maculatus in Río de la Plata (Argentina). These were used for studying the preference of species on different gill-hemibranches, niche breadth and niche overlap between species. It was found that congeneric species had a generic-specific preference for certain gill-hemibranches. Niche breadth appeared to be related to the number of individuals of each species. Niche overlap between the species is discussed.


Assuntos
Peixes-Gato/parasitologia , Brânquias/parasitologia , Trematódeos/fisiologia , Animais , Peixes-Gato/anatomia & histologia , Ecologia , Brânquias/anatomia & histologia , Interações Hospedeiro-Parasita , Especificidade da Espécie
13.
Folia Parasitol (Praha) ; 46(4): 263-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10730198

RESUMO

Differences in the occurrence of monogeneans on lamellae of fish gill arches were observed in this study. These differences were attributed to variations in water current on the gill surfaces or to greater area of certain arches. Two computer simulation programs based on gill area and water current were written to generate parasite metapopulations with clumped patterns. The results obtained were compared with true distributions of selected freshwater monogenean taxa. The combination of both theoretical models (gill area and water current) had greater explanatory power than either of the models alone.


Assuntos
Peixes/parasitologia , Brânquias/parasitologia , Trematódeos/fisiologia , Animais , Simulação por Computador , Água Doce , Brânquias/fisiologia , Interações Hospedeiro-Parasita , Modelos Biológicos , Probabilidade
14.
Rev Invest Clin ; 50(2): 105-11, 1998.
Artigo em Espanhol | MEDLINE | ID: mdl-9658928

RESUMO

OBJECTIVE: A case control study to find out if Cuba's epidemic neuropathy was a result of one of the following causes: (1) an infectious process, (2) exposure to one or more toxical agents, (3) low intake of one or more nutrients, or (4) more than one of such causes and their interactions. MATERIAL AND METHODS: A total of 311 cases of epidemic neuropathy with optic and peripheral symptoms and 377 controls were studied. A questionnaire with 55 items was employed to document exposure to factors determined by the etiologic hypothesis. Data analysis was done separately for the optical and peripheral types of the disease. RESULTS: No association was found between illness and any deficiency of basic sanitation for both types of neuropathy. Acute stress, irregularities in food intake, body weight loss in the last 12 months and other indicators of nutritional deficiencies were associated to both clinical manifestations, although they were also high in the controls. Low frequency of illness was found for people living with diseased persons. Females had a significant high risk of illness in the peripheral manifestations whereas smoking was the only toxical risk factor in optical neuropathy. Nutritional deficiencies together with unidentified personal factors were the main associations for illness outcome; smoking increased significantly the risk of optical neuropathy. CONCLUSIONS: 1. The infection etiology was unsupported in the study. 2. Smoking appeared as a factor for the optical neuropathy. 3. Stress induced by vital events were significantly associated with the disease. 4. Both types of the neuropathy were associated to body weight loss and other indicators of nutritional deficit.


Assuntos
Surtos de Doenças , Doenças do Nervo Óptico/epidemiologia , Doenças do Sistema Nervoso Periférico/epidemiologia , Estudos de Casos e Controles , Cuba/epidemiologia , Feminino , Humanos , Infecções/epidemiologia , Masculino , Distúrbios Nutricionais/epidemiologia , Doenças do Nervo Óptico/etiologia , Doenças do Sistema Nervoso Periférico/etiologia , Fatores de Risco , Fumar , Redução de Peso
15.
Urol Clin North Am ; 20(3): 373-82, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8351764

RESUMO

Advancements in the management of urologic complications such as the neurogenic bladder have been essential to improving the quality of life and longevity of patients with spinal cord injury. These advances are discussed in greater detail in the subsequent articles in this issue. Despite the many improvements that have been made in post-trauma care, spinal cord injury remains a devastating lesion of the nervous system. Current therapies have not proved to be particularly effective in preventing or reversing damage to the spinal cord. Still, every effort should be made to preserve remaining function and to prevent complications. The care of these patients has been significantly improved with the development of specialized multidisciplinary centers. The emphasis in current treatment focuses on rehabilitation and adaptation to the disability and on prevention of secondary disabilities. Research in basic and clinical neuroscience will result in better, more useful care and treatment for those with spinal cord injury. However, even then, a neurorehabilitation team will be essential to care for these patients. Continuing efforts must be made to ensure that people with spinal cord injury lead full and productive lives.


Assuntos
Traumatismos da Medula Espinal , Feminino , História do Século XVIII , História do Século XIX , História do Século XX , História Antiga , Humanos , Masculino , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/história , Traumatismos da Medula Espinal/terapia , Síndrome
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