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1.
J Affect Disord ; 310: 106-115, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35525507

RESUMO

BACKGROUND: Remote sensing for the measurement and management of long-term conditions such as Major Depressive Disorder (MDD) is becoming more prevalent. User-engagement is essential to yield any benefits. We tested three hypotheses examining associations between clinical characteristics, perceptions of remote sensing, and objective user engagement metrics. METHODS: The Remote Assessment of Disease and Relapse - Major Depressive Disorder (RADAR-MDD) study is a multicentre longitudinal observational cohort study in people with recurrent MDD. Participants wore a FitBit and completed app-based assessments every two weeks for a median of 18 months. Multivariable random effects regression models pooling data across timepoints were used to examine associations between variables. RESULTS: A total of 547 participants (87.8% of the total sample) were included in the current analysis. Higher levels of anxiety were associated with lower levels of perceived technology ease of use; increased functional disability was associated with small differences in perceptions of technology usefulness and usability. Participants who reported higher system ease of use, usefulness, and acceptability subsequently completed more app-based questionnaires and tended to wear their FitBit activity tracker for longer. All effect sizes were small and unlikely to be of practical significance. LIMITATIONS: Symptoms of depression, anxiety, functional disability, and perceptions of system usability are measured at the same time. These therefore represent cross-sectional associations rather than predictions of future perceptions. CONCLUSIONS: These findings suggest that perceived usability and actual use of remote measurement technologies in people with MDD are robust across differences in severity of depression, anxiety, and functional impairment.


Assuntos
Transtorno Depressivo Maior , Transtornos de Ansiedade , Estudos Transversais , Transtorno Depressivo Maior/diagnóstico , Humanos , Recidiva , Tecnologia de Sensoriamento Remoto
2.
Theriogenology ; 123: 37-44, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30273739

RESUMO

The overall aim of this work was to study the influence of the hematopoietic growth factors erythropoietin (EPO) and kit ligand (KITL) during bovine oocyte in vitro maturation (IVM). The effect of adding different concentrations of EPO or KITL to maturation medium was evaluated analyzing oocyte nuclear maturation, cumulus cells apoptosis, embryo cleavage, reactive oxygen species (ROS) production in matured oocytes and cleaved embryos and the developmental competence to the blastocyst stage. No significant differences were observed in the percentage of oocytes that completed nuclear maturation among treatments, but the percentages of cleaved embryos and blastocysts obtained increased. With the addition of both hematopoietic growth factors the percentage of cumulus cells undergoing apoptosis decreased, the number of blastomeres per cleaved embryo was larger and ROS production per cleaved embryo increased. In conclusion, although the addition of EPO and KITL hematopoietic growth factors during bovine oocyte IVM had no impact on nuclear maturation, it had a positive effect on oocyte cytoplasmic maturation and developmental competence.


Assuntos
Bovinos/embriologia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Eritropoetina/farmacologia , Fator de Células-Tronco/farmacologia , Animais , Fertilização in vitro/veterinária , Técnicas de Maturação in Vitro de Oócitos
7.
Med Phys ; 40(5): 051906, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23635276

RESUMO

PURPOSE: The authors have developed a trimodal PET∕SPECT∕CT scanner for small animal imaging. The gamma ray subsystems are based on monolithic crystals coupled to multianode photomultiplier tubes (MA-PMTs), while computed tomography (CT) comprises a commercially available microfocus x-ray tube and a CsI scintillator 2D pixelated flat panel x-ray detector. In this study the authors will report on the design and performance evaluation of the multimodal system. METHODS: X-ray transmission measurements are performed based on cone-beam geometry. Individual projections were acquired by rotating the x-ray tube and the 2D flat panel detector, thus making possible a transaxial field of view (FOV) of roughly 80 mm in diameter and an axial FOV of 65 mm for the CT system. The single photon emission computed tomography (SPECT) component has a dual head detector geometry mounted on a rotating gantry. The distance between the SPECT module detectors can be varied in order to optimize specific user requirements, including variable FOV. The positron emission tomography (PET) system is made up of eight compact modules forming an octagon with an axial FOV of 40 mm and a transaxial FOV of 80 mm in diameter. The main CT image quality parameters (spatial resolution and uniformity) have been determined. In the case of the SPECT, the tomographic spatial resolution and system sensitivity have been evaluated with a (99m)Tc solution using single-pinhole and multi-pinhole collimators. PET and SPECT images were reconstructed using three-dimensional (3D) maximum likelihood and ordered subset expectation maximization (MLEM and OSEM) algorithms developed by the authors, whereas the CT images were obtained using a 3D based FBP algorithm. RESULTS: CT spatial resolution was 85 µm while a uniformity of 2.7% was obtained for a water filled phantom at 45 kV. The SPECT spatial resolution was better than 0.8 mm measured with a Derenzo-like phantom for a FOV of 20 mm using a 1-mm pinhole aperture collimator. The full width at half-maximum PET radial spatial resolution at the center of the field of view was 1.55 mm. The SPECT system sensitivity for a FOV of 20 mm and 15% energy window was 700 cps∕MBq (7.8 × 10(-2)%) using a multi-pinhole equipped with five apertures 1 mm in diameter, whereas the PET absolute sensitivity was 2% for a 350-650 keV energy window and a 5 ns timing window. Several animal images are also presented. CONCLUSIONS: The new small animal PET∕SPECT∕CT proposed here exhibits high performance, producing high-quality images suitable for studies with small animals. Monolithic design for PET and SPECT scintillator crystals reduces cost and complexity without significant performance degradation.


Assuntos
Imagem Multimodal/instrumentação , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Animais , Calibragem , Desenho de Equipamento , Processamento de Imagem Assistida por Computador , Camundongos , Ratos
8.
Comput Biol Med ; 43(8): 1053-61, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23706690

RESUMO

We suggest a symmetric-polar pixellation scheme which makes possible a reduction of the computational cost for expectation maximization (EM) iterative algorithms. The proposed symmetric-polar pixellation allows us to deal with 3D images as a whole problem without dividing the 3D problem into 2D slices approach. Performance evaluation of each approach in terms of stability and image quality is presented. Exhaustive comparisons between all approaches were conducted in a 2D based image reconstruction model. From these 2D approaches, that showing the best performances were finally implemented and evaluated in a 3D based image reconstruction model. Comparison to 3D images reconstructed with FBP is also presented. Although the algorithm is presented in the context of computed tomography (CT) image reconstruction, it can be applied to any other tomographic technique as well, due to the fact that the only requirement is a scanning geometry involving measurements of an object under different projection angles. Real data have been acquired with a small animal (CT) scanner to verify the proposed mathematical description of the CT system.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/instrumentação
9.
Int Angiol ; 31(5): 444-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22990507

RESUMO

AIM: Cardiovascular disease (CV) is the second leading cause of morbidity and mortality in chronic obstructive pulmonary disease (COPD). Peripheral arterial disease (PAD) is associated with cardiovascular disease, and its risk factors are common to other atherosclerotic diseases. The objective is to determine the prevalence of PAD in a population of patients with COPD using the ankle / brachial index (ABI) and to investigate the relationship between PAD and lung disease severity. METHODS: In a prospective cross-sectional study, 246 patients with COPD were recruited. Patients were enrolled consecutively according to their admission to Povisa hospital from September 1, 2008, until March 1, 2010, and were assessed by clinical history, spirometry and ABI. The COPD severity was graded by GOLD criteria in spirometry. RESULTS: Overall, 84 patients (36.8%) had abnormal ABI results and 59 (70.2%) were asymptomatic for PAD. COPD patients with PAD had a higher prevalence of moderate to severe COPD (61.9% vs. 41.7%, P=0.004), lower mean forced expiratory volume in 1 second (FEV1) values (46.7% ± 15 vs. 52.3±14%, P=0.001) and a higher prevalence of hypertension (69% vs. 54.3%, P=0.03) and previous cardiovascular disease (34.5% vs. 21.3%, P=0.03). CONCLUSION: There was a high prevalence of asymptomatic PAD in the COPD patients we examined. Abnormal ABI results were associated with a higher prevalence of cardiovascular risk factors and more severe lung disease. The diagnosis of peripheral arterial disease in COPD is important because this is an entity that limits the patient's physical activity and impairs their quality of life in addition to turn it into a high cardiovascular risk patient that requiring additional therapeutic measures.


Assuntos
Doença Arterial Periférica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Índice Tornozelo-Braço , Doenças Assintomáticas , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Modelos Logísticos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doença Arterial Periférica/diagnóstico , Prevalência , Prognóstico , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Espanha/epidemiologia , Espirometria
10.
Rev. esp. anestesiol. reanim ; 59(6): 315-320, jun.-jul. 2012.
Artigo em Espanhol | IBECS | ID: ibc-100753

RESUMO

Objetivos. Dada la creciente evidencia a favor de una relación entre el tiempo de conservación de los concentrados de hematíes y las complicaciones postransfusionales, nos planteamos analizar la relación existente entre los niveles de enzima arginasa, parámetros bioquímicos y de hemólisis, con el tiempo de conservación de concentrados de hematíes transfundidos. Material y métodos. Diseñamos un estudio prospectivo que incluyó 24 unidades de concentrado de hematíes, que habían sido transfundidos consecutivamente a pacientes de nuestro hospital. Luego de registrar el tiempo de conservación de cada bolsa, se extrajeron 15ml de sangre para determinar la actividad arginasa, los datos bioquímicos y de hemólisis. Se realizó un análisis univariante de todos los parámetros registrados y se incluyeron aquellos que resultaron significativos en un modelo de regresión múltiple (p<0,05). Resultados. El tiempo promedio de conservación fue de 18,6±6,1 días (rango: 6-31 días), con un hematocrito de 59,8%±0,05%, una hemoglobina 20,3±1,8g/dl, un pH de 6,5±0,1 y una actividad arginasa de 140,1±124,0 mU/ml. Se observó una relación lineal en el análisis univariante entre el tiempo de conservación y el pH (p=0,001), el HCO3act (p=0,001), el índice hemolítico (p=0,035) y la SpO2 (p=0,01). Una vez ajustados las variables de confusión procedentes del modelo univariante, se observó una relación lineal entre la actividad arginasa y el tiempo de conservación (p=0,031). Conclusiones. Nuestro trabajo muestra una relación lineal directamente proporcional entre el tiempo de conservación de los concentrados de hematíes y la actividad arginasa presente en los mismos. Sugerimos que estos hallazgos podrían estar relacionados con la elevada incidencia de complicaciones tras la transfusión que puede ser directamente proporcional a su tiempo de conservación(AU)


Objectives. Given the increasing evidence regarding a relationship between packed red blood cells storage time and post-transfusion complications, we decided to determine the relationship between the arginase enzyme levels, biochemical parameters and haemolysis, with the storage time of transfused packed red blood cells. Material and methods. We designed a prospective study that included 24 units of packed cells that had been consecutively transfused to patients of our hospital. After recording the storage time of each bag, 15ml of blood was removed to determine arginase activity, biochemical parameters and haemolysis. A univariate analysis was performed on all the recorded parameters, and included those that were significant in the multiple regression model (P<.05). Results. The mean storage time was 18.6±6.1 days (range: 6-31 days), with a haematocrit of 59.8%±0.05%, a haemoglobin of 20.3±1.8g/dl, a pH of 6.5±0.1, and an arginase activity of 140.1±124.0mU/ml. A linear relationship was observed in the univariate analysis between the storage time and the pH (P=.001), the actualHCO3 (P=.001), the haemolysis index (P=.035) and the SpO2 (P=.01). Once adjusted for the confounding variables of the univariate model, a linear relationship was observed between the arginase activity and the storage time (P=.031). Conclusions. Our study shows a directly proportional linear relationship between the storage time of packed red blood cells and their arginase activity. We suggest that these findings could be associated with the high incidence of complications after transfusion that may be directly proportional to their storage time(AU)


Assuntos
Humanos , Masculino , Feminino , Arginase/metabolismo , Eritrócitos/metabolismo , Eritrócitos/fisiologia , Transfusão de Sangue/métodos , Hemólise , Hemólise/fisiologia , Transfusão de Componentes Sanguíneos/tendências , Estudos Prospectivos , Análise de Variância
11.
Rev Esp Anestesiol Reanim ; 59(6): 315-20, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-22703829

RESUMO

OBJECTIVES: Given the increasing evidence regarding a relationship between packed red blood cells storage time and post-transfusion complications, we decided to determine the relationship between the arginase enzyme levels, biochemical parameters and haemolysis, with the storage time of transfused packed red blood cells. MATERIAL AND METHODS: We designed a prospective study that included 24 units of packed cells that had been consecutively transfused to patients of our hospital. After recording the storage time of each bag, 15 ml of blood was removed to determine arginase activity, biochemical parameters and haemolysis. A univariate analysis was performed on all the recorded parameters, and included those that were significant in the multiple regression model (P<.05). RESULTS: The mean storage time was 18.6±6.1 days (range: 6-31 days), with a haematocrit of 59.8%±0.05%, a haemoglobin of 20.3±1.8 g/dl, a pH of 6.5±0.1, and an arginase activity of 140.1±124.0 mU/ml. A linear relationship was observed in the univariate analysis between the storage time and the pH (P=.001), the actual HCO(3) (P=.001), the haemolysis index (P=.035) and the SpO(2) (P=.01). Once adjusted for the confounding variables of the univariate model, a linear relationship was observed between the arginase activity and the storage time (P=.031). CONCLUSIONS: Our study shows a directly proportional linear relationship between the storage time of packed red blood cells and their arginase activity. We suggest that these findings could be associated with the high incidence of complications after transfusion that may be directly proportional to their storage time.


Assuntos
Arginase/sangue , Preservação de Sangue , Eritrócitos/enzimologia , Bicarbonatos/sangue , Transfusão de Eritrócitos , Hematócrito , Hemoglobinas/análise , Hemólise , Humanos , Concentração de Íons de Hidrogênio , Estudos Prospectivos , Fatores de Tempo
18.
Neuroscience ; 154(1): 355-69, 2008 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-18384972

RESUMO

It is well established that restricted mechanical lesions of the cochlea result in reorganization of the tonotopic map in the auditory thalamus and cortex, but it is unclear whether acoustic trauma produces similar effects at earlier stages of the auditory pathways. To test whether the tonotopic map is reorganized after acoustic trauma at the midbrain level, i.e. the inferior colliculus (IC), we exposed rats to an acoustic trauma and let them survive for at least 5 weeks to ensure that we produced a permanent threshold shift. Experiments were carried out in urethane-anesthetized animals 35-296 days after the traumatic exposure. The acoustic lesions were assessed by measuring the compound action potential. We mapped the frequency organization of the IC using multiunit recordings. In addition, we recorded frequency response areas (FRAs) when a single unit was isolated (N=142). The results show that acoustic trauma produces a persistent reorganization of the tonotopic map and that the normal stepwise representation of sound frequency in the IC is profoundly disrupted. Although the reorganization in the IC is similar to that previously described in the cortex and thalamus in that the affected area appears to be invaded by the adjacent normal frequencies, changes in thresholds and FRAs in these regions are different from those in the forebrain. We conclude that most of the changes can be explained by the residual-response hypothesis [Irvine DR, Rajan R, Smith S (2003) Effects of restricted cochlear lesions in adult cats on the frequency organization of the inferior colliculus. J Comp Neurol 467:354-374]. Plastic reorganization of frequency response areas and tonotopic organization does not seem to occur at the midbrain level following acoustic trauma in adult animals in a manner similar to that previously shown in the auditory cortex. Maintaining the stability of the neuronal circuitry for frequency coding in the IC may be important for the treatment of noise-induced hearing loss.


Assuntos
Potenciais de Ação/fisiologia , Mapeamento Encefálico , Perda Auditiva Provocada por Ruído/patologia , Colículos Inferiores/fisiopatologia , Estimulação Acústica/efeitos adversos , Estimulação Acústica/métodos , Animais , Audiometria/métodos , Limiar Auditivo/fisiologia , Modelos Animais de Doenças , Eletrodos Implantados , Feminino , Colículos Inferiores/patologia , Masculino , Psicofísica , Ratos , Análise Espectral
19.
Mar Pollut Bull ; 56(4): 686-703, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18321533

RESUMO

The ESEOO Project, launched after the Prestige crisis, has boosted operational oceanography capacities in Spain, creating new operational oceanographic services and increasing synergies between these new operational tools and already existing systems. In consequence, the present preparedness to face an oil-spill crisis is enhanced, significantly improving the operational response regarding ocean, meteorological and oil-spill monitoring and forecasting. A key aspect of this progress has been the agreement between the scientific community and the Spanish Search and Rescue Institution (SASEMAR), significantly favoured within the ESEOO framework. Important achievements of this collaboration are: (1) the design of protocols that at the crisis time provide operational state-of-the-art information, derived from both forecasting and observing systems; (2) the establishment, in case of oil-spill crisis, of a new specialized unit, named USyP, to monitor and forecast the marine oceanographic situation, providing the required met-ocean and oil-spill information for the crisis managers. The oil-spill crisis scenario simulated during the international search and rescue Exercise "Gijón-2006", organized by SASEMAR, represented an excellent opportunity to test the capabilities and the effectiveness of this USyP unit, as well as the protocols established to analyze and transfer information. The results presented in this work illustrate the effectiveness of the operational approach, and constitute an encouraging and improved base to face oil-spill crisis.


Assuntos
Planejamento em Desastres/métodos , Desastres , Óleos Combustíveis/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Oceano Atlântico , Previsões , Modelos Teóricos , Espanha , Fatores de Tempo , Movimentos da Água
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