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1.
Histochem Cell Biol ; 150(4): 379-393, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29931444

RESUMO

Microtissues (MT) are currently considered as a promising alternative for the fabrication of natural, 3D biomimetic functional units for the construction of bio-artificial substitutes by tissue engineering (TE). The aim of this study was to evaluate the possibility of generating mesenchymal cell-based MT using human umbilical cord Wharton's jelly stromal cells (WJSC-MT). MT were generated using agarose microchips and evaluated ex vivo during 28 days. Fibroblasts MT (FIB-MT) were used as control. Morphometry, cell viability and metabolism, MT-formation process and ECM synthesis were assessed by phase-contrast microscopy, functional biochemical assays, and histological analyses. Morphometry revealed a time-course compaction process in both MT, but WJSC-MT resulted to be larger than FIB-MT in all days analyzed. Cell viability and functionality evaluation demonstrated that both MT were composed by viable and metabolically active cells, especially the WJSC during 4-21 days ex vivo. Histology showed that WJSC acquired a peripheral pattern and synthesized an extracellular matrix-rich core over the time, what differed from the homogeneous pattern observed in FIB-MT. This study demonstrates the possibility of using WJSC to create MT containing viable and functional cells and abundant extracellular matrix. We hypothesize that WJSC-MT could be a promising alternative in TE protocols. However, future cell differentiation and in vivo studies are still needed to demonstrate the potential usefulness of WJSC-MT in regenerative medicine.


Assuntos
Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Geleia de Wharton/citologia , Sobrevivência Celular , Matriz Extracelular/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Geleia de Wharton/metabolismo
2.
AIDS Behav ; 22(3): 800-805, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28063073

RESUMO

Little research has focused on suicidality in the era of successful antiretroviral therapy among those engaged in HIV care. We performed a study of 648 clinic patients who completed a psychological and behavioral annual assessment in 2012. Depressive symptoms were measured using the Patient Health Questionnaire-9 (PHQ-9), suicidal ideation was measured by the last item of the scale. Anxiety symptoms were measured using the Generalized Anxiety Disorder-7 questionnaire (GAD-7). HIV biomedical markers were abstracted from medical records. Suicidal ideation was reported among 13% (n = 81) of the sample. Individuals endorsing suicidality were more likely to have unsuppressed viral loads, moderate to severe anxiety symptoms and consider themselves to be homeless (p < 0.01 for all). After adjusting for confounders, homeless individuals and those endorsing moderate to severe anxiety symptoms had higher odds of reporting suicidality. Results suggest basic needs must be met to complement HIV management efforts. Furthermore, better understanding of how psychological distress symptoms are expressed and how to manage them may better inform barriers to HIV management.


Assuntos
Ansiedade/epidemiologia , Depressão/epidemiologia , Infecções por HIV/psicologia , Ideação Suicida , Adolescente , Adulto , Idoso , Ansiedade/diagnóstico , Ansiedade/psicologia , Estudos Transversais , Depressão/diagnóstico , Depressão/psicologia , Feminino , HIV , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Questionário de Saúde do Paciente , Estresse Psicológico , Inquéritos e Questionários , Estados Unidos/epidemiologia , Carga Viral , Adulto Jovem
3.
Neuroimage ; 163: 480-486, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28687516

RESUMO

Here we show how it is possible to make estimates of brain structure based on MEG data. We do this by reconstructing functional estimates onto distorted cortical manifolds parameterised in terms of their spherical harmonics. We demonstrate that both empirical and simulated MEG data give rise to consistent and plausible anatomical estimates. Importantly, the estimation of structure from MEG data can be quantified in terms of millimetres from the true brain structure. We show, for simulated data, that the functional assumptions which are closer to the functional ground-truth give rise to anatomical estimates that are closer to the true anatomy.


Assuntos
Encéfalo/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Magnetoencefalografia/métodos , Algoritmos , Simulação por Computador , Humanos , Modelos Neurológicos
5.
Neuroimage ; 84: 476-87, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24041874

RESUMO

The MEG/EEG inverse problem is ill-posed, giving different source reconstructions depending on the initial assumption sets. Parametric Empirical Bayes allows one to implement most popular MEG/EEG inversion schemes (Minimum Norm, LORETA, etc.) within the same generic Bayesian framework. It also provides a cost-function in terms of the variational Free energy-an approximation to the marginal likelihood or evidence of the solution. In this manuscript, we revisit the algorithm for MEG/EEG source reconstruction with a view to providing a didactic and practical guide. The aim is to promote and help standardise the development and consolidation of other schemes within the same framework. We describe the implementation in the Statistical Parametric Mapping (SPM) software package, carefully explaining each of its stages with the help of a simple simulated data example. We focus on the Multiple Sparse Priors (MSP) model, which we compare with the well-known Minimum Norm and LORETA models, using the negative variational Free energy for model comparison. The manuscript is accompanied by Matlab scripts to allow the reader to test and explore the underlying algorithm.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Magnetoencefalografia/métodos , Reconhecimento Automatizado de Padrão/métodos , Inteligência Artificial , Teorema de Bayes , Interpretação Estatística de Dados , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
MethodsX ; 12: 102686, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38585179

RESUMO

One of the initial steps in the preprocessing of digital fundoscopy images is the identification of pixels containing relevant information. This can be achieved through different approaches, one of them is implementing background extraction, reducing the set of pixels to be analyzed later in the process. In this work, we present a background extraction method for digital fundoscopy images based on computational topology. By interpreting binarized images as cubical complexes and extracting their homological groups in 1 and 2 dimensions we identify a subset of luminescence values that can be used to binarize the original grayscale image, obtaining a mask to achieve background extraction. This method is robust to noise and suboptimal image quality, facilitating the analytical pipeline in the context of computer aided diagnosis approaches. This method facilitates the segmentation of the background of a digital fundoscopy image, which allows further methods to focus on pixels with relevant information (eye fundus). This tool is best suited to be implemented in the preprocessing stages of the analytical pipeline by computational ophthalmology specialists.•It is robust to noise and low-quality images.•Output provides an ideal scenario for down-the-line analysis by facilitating only relevant pixels in a digital fundoscopy.

8.
Rev Clin Esp (Barc) ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39313029

RESUMO

OBJECTIVE: The objective is to analyze the prevalence of Alzheimer's disease in patients with and without a diagnosis of different autoimmune diseases and the possible association between both pathologies. PATIENTS AND METHODS: A multicenter, retrospective, cohort study was conducted to study the prevalence of Alzheimer's disease among patients diagnosed with various autoimmune diseases compared to the general population. Data from electronic medical records from the Castilla-La Mancha healthcare system were analyzed using Natural Language Processing through the Savana Manager® artificial intelligence clinical platform. A total of 1,028,356 patients were analyzed, including 28,920 individuals with Alzheimer's disease and 999,436 control patients. RESULTS: Out of the 12 autoimmune diseases analyzed, 5 showed a significant association with Alzheimer's disease with p < 0.05. Myasthenia gravis had an increased prevalence of AD with OR 1.49 (95% CI 1.11-2), systemic lupus erythematosus with OR 2.42 (95% CI 2.02-2.88), rheumatoid arthritis with OR 1.38 (95% CI 1.24-1.54), polymyalgia rheumatica with OR 2.01 (95% CI 1.08-2.23), and pernicious anemia with OR 2.06 (95% CI 1.59-2.66). The remaining autoimmune diseases analyzed did not show a higher prevalence of Alzheimer's disease compared to the general population. CONCLUSIONS: There may be an association between certain systemic autoimmune diseases and Alzheimer's disease. Further studies are needed to confirm our findings, establish causality, and explore the underlying mechanisms of this association.

9.
Prev Med Rep ; 36: 102458, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37886723

RESUMO

Skin cancer incidence is increasing worldwide. Late adolescence and young adulthood are fundamental stages of life to acquire good sun exposure practices, regarding both personal involvement in skin cancer prevention and being a role model for others, especially in a health education environment. This descriptive cross-sectional study is based on the validated CHACES questionnaire to study sun exposure and photoprotection behavior among students and teachers at the School of Health Sciences in the National University of Chimborazo, Riobamba (Ecuador). University members (814 students (89.8 %) and 93 teachers (10.2 %)) were studied, with a predominance of females and light-skin phototypes in both groups. Similar results were obtained regarding sun exposure, with higher recreative exposure in the teachers' group and higher occupational exposure in students. However, students significantly showed lower avoiding midday sun (41.9 % vs 60.9 %), and lower use of sunglasses (10.1 % vs. 41.6 %). Attitudes towards the sun and photoprotection knowledge issues were also equivalent between students and teachers (6.1/10 vs 6.2/10). Students' sunburn rate last year reaches 88.4 % and 52.7 % in teachers (p < 0.001). Using a multivariable logistic regression model, we identified risk factors associated with a greater risk of sunburn in our population. This study highlights areas to be improved regarding knowledge, attitudes and, especially, practices of photoprotection, among students and teachers at the University of Chimborazo. These results point out that awareness-raising campaigns should be implemented to reduce sunburns, morbidity and mortality of skin cancer in this environment.

10.
Neuroimage ; 60(2): 1194-204, 2012 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-22289800

RESUMO

There is uncertainty introduced when a cortical surface based model derived from an anatomical MRI is used to reconstruct neural activity with MEG data. This is a specific case of a problem with uncertainty in parameters on which M/EEG lead fields depend non-linearly. Here we present a general mathematical treatment of any such problem with a particular focus on co-registration. We use a Metropolis search followed by Bayesian Model Averaging over multiple sparse prior source inversions with different headlocation/orientation parameters. Based on MEG data alone we can locate the cortex to within 4mm at empirically realistic signal to noise ratios. We also show that this process gives improved posterior distributions on the estimated current distributions, and can be extended to make inference on the locations of local maxima by providing confidence intervals for each source.


Assuntos
Magnetoencefalografia/estatística & dados numéricos , Incerteza , Teorema de Bayes
12.
Heliyon ; 8(3): e09026, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35252619

RESUMO

Molecular dynamic (MD) calculations were performed to investigate the thermodynamic and structural properties of lead fluoride (PbF2) by using a proposed inter-ionic temperature-dependent potential. This potential allows calculating with high precision the linear thermal expansivity and the lattice parameter as a temperature function. In addition, the potential can be represented as a sum of two contributions, a temperature-independent potential added to another temperature-dependent potential, considered last as a correction justified by the one-dimensional Newtonian quantum equation. Two fitting regions were considered, the first region from 300 to 700 K and the other one from 700 to 900 K. These regions arise naturally due to the smooth and continuous transition that PbF2 undergoes until it reaches the superionic state and, allows us to model with high precision the anomaly in the dependence of the lattice parameter with the temperature of this material, a feature that until now under the molecular dynamic method has not been studied. These results are all in good agreement with the experimental measurements.

13.
Soc Neurosci ; 15(4): 398-407, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32107978

RESUMO

Ex-combatants often exhibit atypical Emotional Processing (EP) such as reduced emphatic levels and higher aggressive attitudes. Social Cognitive Training (SCT) addressing socio-emotional components powerfully improve social interaction among Colombian ex-combatants. However, with narrow neural evidence, this study offers a new testimony. A sample of 28 ex-combatants from Colombian illegal armed groups took part in this study, split into 15 for SCT and 13 for the conventional program offered by the Governmental Reintegration Route. All of them were assessed before and after the intervention with a protocol that included an EP task synchronized with electroencephalographic recordings. We drew behavioral scores and brain connectivity (Coherency) metrics from task performance. Behavioral scores yielded no significant effects. Increased post-intervention connectivity in the delta band was observed during negative emotional processing only SCT group. Positive emotions exposed distinctive gamma band connectivity that differentiate groups. These results suggest that SCT can trigger covert neurofunctional reorganization in ex-combatants embarked on the reintegration process even when overt behavioral improvements are not yet apparent. Such covert functional changes may be the neural signature of compensatory mechanisms necessary to reshape behaviors adaptively. This novel framework may inspire cutting-edge translational research at the crossing of neuroscience, sociology, and public policy-making.


Assuntos
Encéfalo/fisiopatologia , Terapia Cognitivo-Comportamental/métodos , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/reabilitação , Veteranos/psicologia , Adulto , Colômbia , Emoções/fisiologia , Feminino , Humanos , Masculino , Transtornos de Estresse Pós-Traumáticos/psicologia
14.
Int J Neural Syst ; 29(6): 1950001, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30859856

RESUMO

In the recent past, estimating brain activity with magneto/electroencephalography (M/EEG) has been increasingly employed as a noninvasive technique for understanding the brain functions and neural dynamics. However, one of the main open problems when dealing with M/EEG data is its non-Gaussian and nonstationary structure. In this paper, we introduce a methodology for enhancing the data covariance estimation using a weighted combination of multiple Gaussian kernels, termed WM-MK, that relies on the Kullback-Leibler divergence for associating each kernel weight to its relevance. From the obtained results of validation on nonstationary and non-Gaussian brain activity (simulated and real-world EEG data), WM-MK proves that the accuracy of the source estimation raises by more effectively exploiting the measured nonlinear structures with high time and space complexity.


Assuntos
Eletroencefalografia/estatística & dados numéricos , Magnetoencefalografia/métodos , Magnetoencefalografia/estatística & dados numéricos , Modelos Estatísticos , Simulação por Computador , Eletroencefalografia/métodos , Humanos
15.
J Healthc Qual Res ; 34(4): 209-216, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31713532

RESUMO

INTRODUCTION: the main aim of this study was to develop and implement a risk map in the Oral and Maxillofacial Surgery Service of the University Hospital «Virgen de las Nieves¼ of Granada to minimize the incidence of adverse effects (AE). MATERIALS AND METHODS: Longitudinal, prospective study carried out in the Oral and Maxillofacial Surgery Service of the Hospital Universitario Virgen de las Nieves of Granada, from June 2017 to May 2018, through the methodology of «Analysis and Failure Mode Effect¼. Management of the different AE was addressed. The following phases were considered as it follows: identification of the problem, identification of AE for within the practice of the oral and maxillofacial surgery that represents a problem in the assistive safety, creation of an interdisciplinary working group, analysis of the current situation in patient safety and risk management using 2analysis tools, SWOT and PITELO, preparation of the patient care process, development of a catalog of AE and preparation of a risk map. RESULTS: A total of 33 AE were identified. The risk map showed a higher incidence of AE in the Surgical Area (22) compared to the areas of Outpatient Clinic and Hospital Discharge (6). A total of 10 critical AE were identified. CONCLUSIONS: The elaboration of a risk map allowed to determine the process of the oral and maxillofacial surgical patient, and to elaborate a catalog of AE.


Assuntos
Procedimentos Cirúrgicos Bucais/efeitos adversos , Segurança do Paciente , Gestão de Riscos/organização & administração , Cirurgia Bucal , Unidades Hospitalares , Humanos , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Medição de Risco/métodos , Gestão de Riscos/métodos
19.
J Healthc Qual Res ; 33(5): 256-263, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30361103

RESUMO

INTRODUCTION: Patient safety in oral and maxillofacial surgery is oriented towards providing patient care by means of adequate risk management that minimises adverse events and fosters a culture of safe clinical practices as the fundamental basis of quality health care. To implement preventive actions are implemented in order to improve patient safety and to reduce the incidence of adverse events, as well as to improve the quality of care. The aim of this report is to implement preventive measures in order to improve the health care of the patient in an Oral and Maxillofacial Surgery Unit by reducing the Adverse Events and proving good quality healthcare. MATERIALS AND METHODS: A longitudinal, prospective, single centre study was conducted using a methodology of analysis of modes of failure and effects of the management of potentially serious adverse events in the Oral and Maxillofacial surgical unit of the University Hospital of Granada (June-November 2017), as well as the preparation and implementation of a series of corrective measures. RESULTS: A total of 33 adverse events were recorded, with 10 of them considered as critical, distributed in different areas of care, and referred from Primary Health Care and from other hospitals. Seven preventive actions were implemented: information to the patient, training actions, improvements in the protocols and procedures, in the care process and clinical practice, as well as the need to set up an adequate checklist, and other miscellaneous. DISCUSSION: The implementation of preventive measures represent a notable advance in the prevention of harm to the patient and the organisation, involving healthcare staff in a safety culture oriented towards quality care.


Assuntos
Erros Médicos/prevenção & controle , Procedimentos Cirúrgicos Bucais/efeitos adversos , Segurança do Paciente , Complicações Pós-Operatórias/prevenção & controle , Qualidade da Assistência à Saúde , Lista de Checagem , Humanos , Procedimentos Cirúrgicos Bucais/normas , Sistemas de Identificação de Pacientes , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Gestão de Riscos/organização & administração
20.
Transplant Proc ; 50(10): 3216-3221, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30577188

RESUMO

INTRODUCTION: Chronic kidney disease (CKD) is a priority problem due to its high prevalence. According to the modalities of renal replacement therapy, kidney transplantation (TR) offers to be the best alternative. TR presents multiple factors of dependence of success; among them is the management of the anatomical variants of the graft and the surgical decision on the basis of these. Therefore, the objective of this study is to determine the frequency of variants in the graft, its surgical management, and the impact on the functionality of the transplanted kidney. MATERIAL AND METHODS: This was an observational, retrospective study of patients in the renal transplant unit of the Siglo XXI National Medical Center from 2002-2016. The analysis begins in the description of the population doing bivariate analysis to establish relative risks. For variables with a central tendency, the parametric tests analysis of variance, Student t paired, and unpaired will be used. In the case of nominal variables, the proportion's difference will be estimated using the chi-square test, establishing significance when P is ≤ .05. SPSS 21 software was used. RESULTS: There were a total of 773 patients, with 576 transplants from living donors and 197 from deceased donors. In the case of the artery, a greater number of variants is observed-27.8% being alive versus 17.3% of the variants found in deceased donors. For the renal vein, 12.7% of the kidneys were taken from living donor vs 6.1% from deceased donors. This required one more day of hospitalization (6 vs 7 days of single vs multiple vessels); likewise, increases in immediate post-transplant infections were 5% for single vessels vs 8% in the case of multiple variants. CONCLUSIONS: The importance of knowing the anatomical variants prior to the TR allows them to plan the potential surgical maneuvers, decreasing the times aimed at improving the immediate functionality of the renal graft, while also considering the increase in hospital expenses due to the greater number of days of hospitalization.


Assuntos
Transplante de Rim/métodos , Rim/anormalidades , Transplantes/anormalidades , Adolescente , Adulto , Idoso , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , México , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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