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1.
Int J Geriatr Psychiatry ; 36(5): 627-646, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33169885

RESUMO

BACKGROUND: Although depression is known to be frequent in Parkinson's disease (PD), it is unclear how mood can change and/or impact on patient's quality of life (QoL) over time. Our aim was to analyze the frequency of depression, mood related factors and the contribution of mood to a patient's QoL perception in regard to disease duration. METHODS: PD patients recruited from the COPPADIS cohort from January 2016 to November 2017 were included in this cross-sectional study. Three groups were defined: <5 years (Group A); from 5 to <10 years (Group B); ≥10 years (Group C). Analysis with well-planned linear regression models was conducted to determine how different factors contribute to mood (Beck Depression Inventory-II [BDI-II] as dependent variable), to health-related QoL (39-item Parkinson's Disease Questionnaire [PDQ-39SI] as dependent variable) and to global QoL (European Health Interview Survey - Quality of Life Eight-Item Index [EUROHIS-QOL8] as dependent variable). RESULTS: Six hundred and sixty-three PD patients (62.6 ± 8.9 years old, 59.6% males) were included: Group A, 50.1% (n = 332); Group B, 33.3% (n = 221) and Group C, 16.6% (n = 110). There were no differences between the three groups in terms of the frequency of depressive symptoms nor the frequency of depression type (major vs. minor vs. subthreshold) (p = 0.729). However, the unique percent variance of PDQ-39SI and EUROHIS-QOL8 explained by BDI-II total score was 2 (23.7%) and threefold (26.9%), respectively, in Group C compared to the other two groups. EUROHIS-QOL8 total score provided the highest unique contribution to mood (16.8%). CONCLUSIONS: Although depression-type frequency does not appear to change over time in PD; the contribution of mood on QoL perception is greater in patients with longer disease duration.


Assuntos
Doença de Parkinson , Idoso , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Doença de Parkinson/epidemiologia , Qualidade de Vida , Inquéritos e Questionários
2.
Eur J Neurol ; 26(11): 1399-1407, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31179586

RESUMO

BACKGROUND AND PURPOSE: In Parkinson's disease (PD), the course of the disorder is highly variable between patients. Well-designed, prospective studies for identifying PD progression biomarkers are necessary. Our aim was to show the results of baseline evaluations of an ongoing global PD project, COPPADIS-2015 (Cohort of Patients with PArkinson's DIsease in Spain, 2015). METHODS: This was an observational, descriptive, nationwide study (Spain). The recruitment period ended in October 2017. Baseline evaluation included more than 15 validated scales and complementary studies in a subgroup of participants. RESULTS: In total, 1174 subjects from 35 centres were considered valid for baseline analysis: 694 patients (62.6 ± 8.9 years old, 60.3% males), 273 caregivers (58.5 ± 11.9 years old, 31.8% males) and 207 controls (61 ± 8.3 years old, 49.5% males). The mean disease duration was 5.5 ± 4.4 years. Hoehn and Yahr stage was 1 or 2 in 90.7% of the patients whilst 33.9% and 18.1% of them presented motor fluctuations and dyskinesias, respectively. The mean Non-Motor Symptoms Scale total score was 45.4 ± 38.1, and 30.4% of the patients presented cognitive impairment, 16.1% major depression, 12.7% impulse control disorder, 7.2% compulsive behaviour, 57.2% pain and 13.2% falls. Compared to the control group, PD patients presented a significantly higher burden of non-motor symptoms and a worse quality of life. More than 300 subjects conducted complementary studies (serum biomarkers, genetic and neuroimaging). CONCLUSIONS: Parkinson's disease is a complex disorder and different non-motor symptoms are frequently present and are more prevalent than in controls. In real clinical practice it is important to ask for them.


Assuntos
Doença de Parkinson/patologia , Idoso , Idoso de 80 Anos ou mais , Cuidadores/estatística & dados numéricos , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Estudos de Coortes , Comorbidade , Progressão da Doença , Transtornos Disruptivos, de Controle do Impulso e da Conduta , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Transtornos dos Movimentos/epidemiologia , Transtornos dos Movimentos/etiologia , Doença de Parkinson/epidemiologia , Doença de Parkinson/psicologia , Estudos Prospectivos , Qualidade de Vida , Fatores Socioeconômicos , Espanha/epidemiologia
3.
Environ Monit Assess ; 191(10): 635, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31522254

RESUMO

This study aimed to analyze the spatial and temporal variation of the vegetation in the northern Argentine Puna, utilizing both field sampling and remote-sensing tools. The study was performed within the Pozuelos Biosphere Reserve (Jujuy province, Argentina), which aims to generate socio-economic development compatible with biodiversity conservation. Our study was designed to analyze the dynamics of the Puna vegetation at local scale and assess and monitor the seasonal (dry and wet seasons), interannual, and spatial variation of the vegetation cover, biomass, dominant species, and vegetation indices. Ten vegetation units (with differences in composition, cover, and high and low stratum biomass) were identified at our study site. The diversity of these vegetation units correlated with geomorphology and soil type. In the dry season, the vegetation unit with greatest vegetation cover and biomass was the Festuca chrysophylla grassland, whereas in the wet season, the units with greatest cover and biomass were vegas (peatlands) and short grasslands. The Festuca chrysophylla grasslands and short grasslands were located in areas with clay soils, except peatlands, associated with valleys and coarse-texture soils. The vegetation indices used (NDVI, SAVI, and MSAVI2) were able to differentiate functional types of vegetation and showed a good statistical fit with cover values. Our results suggest that the integrated utilization of remote-sensing tools and field surveys improves the assessment of the Puna vegetation and would allow a periodic monitoring at production unit scale taking into account its spatial and temporal variation.


Assuntos
Monitoramento Ambiental/métodos , Pradaria , Plantas/classificação , Argentina , Biodiversidade , Biomassa , Parques Recreativos , Tecnologia de Sensoriamento Remoto , Estações do Ano , Solo/química
5.
J Chem Ecol ; 39(3): 398-412, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23475221

RESUMO

Prescribed burning (PB) is gaining popularity as a low-cost forest protection measure that efficiently reduces fuel build-up, but its effects on tree health and growth are poorly understood. Here, we evaluated the impact of PB on plant defenses in Mediterranean pine forests (Pinus halepensis and P. nigra ssp. laricio). These chemical defenses were estimated based on needle secondary metabolites (terpenes and phenolics including flavonoids) and discussed in terms of chlorophyll fluorescence and soil nutrients. Three treatments were applied: absence of burning (control plots); single burns (plots burned once); and repeated burns (plots burned twice). For single burns, we also explored changes over time. In P. laricio, PB tended to trigger only minor modifications consisting exclusively of short-lived increases (observed within 3 months after PB) in flavonoid index, possibly due to the leaf temperature increase during PB. In P. halepensis, PB had detrimental effects on physiological performance, consisting of (i) significant decreases in actual PSII efficiency (ΦPSII) in light-adapted conditions after repeated PB, and (ii) short-lived decreases in variable-to-maximum fluorescence ratio (Fv/Fm) after single PB, indicating that PB actually stressed P. halepensis trees. Repeated PB also promoted terpene-like metabolite production, which increased 2 to 3-fold compared to control trees. Correlations between terpene metabolites and soil chemistry were found. These results suggest that PB impacts needle secondary metabolism both directly (via a temperature impact) and indirectly (via soil nutrients), and that these impacts vary according to species/site location, frequency and time elapsed since last fire. Our findings are discussed with regard to the use of PB as a forest management technique and its consequences on plant investment in chemical defenses.


Assuntos
Conservação dos Recursos Naturais/métodos , Incêndios , Pinus/metabolismo , Folhas de Planta/metabolismo , Metabolismo Secundário , Pinus/crescimento & desenvolvimento , Solo/química , Terpenos/metabolismo , Árvores/crescimento & desenvolvimento
6.
Med Phys ; 39(10): 6351-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23039671

RESUMO

PURPOSE: Accurate delineation of the rectum is of high importance in off-line adaptive radiation therapy since it is a major dose-limiting organ in prostate cancer radiotherapy. The intensity-based deformable image registration (DIR) methods cannot create a correct spatial transformation if there is no correspondence between the template and the target images. The variation of rectal filling, gas, or feces, creates a non correspondence in image intensities that becomes a great obstacle for intensity-based DIR. METHODS: In this study the authors have designed and implemented a semiautomatic method to create a rectum mask in pelvic computed tomography (CT) images. The method, that includes a DIR based on the demons algorithm, has been tested in 13 prostate cancer cases, each comprising of two CT scans, for a total of 26 CT scans. RESULTS: The use of the manual segmentation in the planning image and the proposed rectum mask method (RMM) method in the daily image leads to an improvement in the DIR performance in pelvic CT images, obtaining a mean value of overlap volume index = 0.89, close to the values obtained using the manual segmentations in both images. CONCLUSIONS: The application of the RMM method in the daily image and the manual segmentations in the planning image during prostate cancer treatments increases the performance of the registration in presence of rectal fillings, obtaining very good agreement with a physician's manual contours.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Pelve/diagnóstico por imagem , Reto/metabolismo , Tomografia Computadorizada por Raios X/métodos , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Reto/diagnóstico por imagem
7.
J Vet Cardiol ; 35: 25-41, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33812131

RESUMO

INTRODUCTION/OBJECTIVES: In the past few years, novel markers such as the interval between the peak and the end of T-wave (Tpte) and Tpte/QT ratio have been shown to have high sensitivity for ventricular arrhythmias and mortality. We analyzed these and other parameters of ventricular repolarization, such as QT interval, QT interval corrected for heart rate (QTc), and QT dispersion (QTd) in dogs with myxomatous mitral valve disease (MMVD). Additionally, we investigated their relationship with the progression of the disease, echocardiographic parameters, and ventricular arrhythmias and assessed their prognostic value with development of clinical signs or mortality as the final outcome. ANIMALS, MATERIALS AND METHODS: Epidemiological, clinical, echocardiographic, and electrocardiographic data were obtained from 236 dogs with MMVD and 15 healthy dogs. Prognostic and survival information was also recorded for the MMVD group. All ventricular repolarization indices were measured in 10 lead electrocardiographic recordings. RESULTS: With the exception of the QT interval, most repolarization markers increased along with the frequency of arrhythmias and with the progression of MMVD. The parameters that best identified ventricular arrhythmias (AUC > 0.7) were Tpte (aVR, rV2, average rV2-V10, average rV2-V4) and Tpte/QT (II, aVR, rV2). In survival analysis, statistically significant markers with the highest differences in median survival were Tpte (maximum of any lead, maximum rV2-V10), QTc aVR, and Tpte rV2. CONCLUSION: Tpte and Tpte/QT are good non-invasive markers for clinical risk stratification in dogs with MMVD.


Assuntos
Doenças do Cão , Doenças das Valvas Cardíacas , Animais , Arritmias Cardíacas/veterinária , Cães , Eletrocardiografia/veterinária , Frequência Cardíaca , Doenças das Valvas Cardíacas/veterinária , Valva Mitral
8.
Parkinsons Dis ; 2021: 8871549, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34094501

RESUMO

INTRODUCTION: In a degenerative disorder such as Parkinson's disease (PD), it is important to establish clinical stages that allow to know the course of the disease. Our aim was to analyze whether a scale combining Hoehn and Yahr's motor stage (H&Y) and the nonmotor symptoms burden (NMSB) (assessed by the nonmotor symptoms scale (NMSS)) provides information about the disability and the patient's quality of life (QoL) with regard to a defined clinical stage. MATERIALS AND METHODS: Cross-sectional study in which 603 PD patients from the COPPADIS cohort were classified according to H&Y (1, stage I; 2, stage II; 3, stage III; 4, stage IV/V) and NMSB (A: NMSS = 0-20; B: NMSS = 21-40; C: NMSS = 41-70; D: NMSS ≥ 71) in 16 stages (HY.NMSB, from 1A to 4D). QoL was assessed with the PDQ-39SI, PQ-10, and EUROHIS-QOL8 and disability with the Schwab&England ADL (Activities of Daily Living) scale. RESULTS: A worse QoL and greater disability were observed at a higher stage of H&Y and NMSB (p < 0.0001). Combining both (HY.NMSB), patients in stages 1C and 1D and 2C and 2D had significantly worse QoL and/or less autonomy for ADL than those in stages 2A and 2B and 3A and 3B, respectively (p < 0.005; e.g., PDQ-39SI in 1D [n = 15] vs 2A [n = 101]: 28.6 ± 17.1 vs 7.9 ± 5.8; p < 0.0001). CONCLUSION: The HY.NMSB scale is simple and reflects the degree of patient involvement more accurately than the H&Y. Patients with a lower H&Y stage may be more affected if they have a greater NMS burden.

9.
Med Phys ; 37(3): 1137-45, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20384249

RESUMO

PURPOSE: Current radiotherapy is progressing to the concept of adaptive radiotherapy, which implies the adaptation of planning along the treatment course. Nonrigid registration is an essential image processing tool for adaptive radiotherapy and image guided radiotherapy, and the three-dimensional (3D) nature of the current radiotherapy techniques requires a 3D quantification of the registration error that existing evaluation methods do not cover appropriately. The authors present a method for 3D evaluation of nonrigid registration algorithms' performance, based on organ delineations, capable of working with near-spherical volumes even in the presence of concavities. METHODS: The evaluation method is composed by a volume shape description stage, developed using a new ad hoc volume reconstruction algorithm proposed by the authors, and an error quantification stage. The evaluation method is applied to the organ delineations of prostate and seminal vesicles, obtained by an automatic segmentation method over images of prostate cancer patients treated with intensity modulated radiation therapy. RESULTS: The volume reconstruction algorithm proposed has been shown to accurately model complex 3D surfaces by the definition of clusters of control points. The quantification method, inspired by the Haussdorf-Chebysev distance, provides a measure of the largest registration error per control direction, defining a valid metric for concave-convex volumes. Summarizing, the proposed evaluation methodology presents accurate results with a high spatial resolution in a negligible computation time in comparison with the nonrigid registration time. CONCLUSIONS: Experimental results show that the metric selected for quantifying the registration error is of utmost importance in a quantitative evaluation based on measuring distances between volumes. The accuracy of the volume reconstruction algorithm is not so relevant as long as the reconstruction is tight enough on the actual volume of the organ. The new evaluation method provides a smooth and accurate volume reconstruction for both the reference and the registered organ, and a complete 3D description of nonrigid registration algorithms' performance, resulting in a useful tool for study and comparison of registration algorithms for adaptive radiotherapy.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Tomografia Computadorizada por Raios X/métodos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Poult Sci ; 88(5): 975-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19359685

RESUMO

The effect of continuously feeding the probiotic microorganism Toyocerin to birds inoculated with Salmonella Enteritidis field-isolated strains on Salmonella Enteritidis prevalence, and performance variables were studied in 2 experiments. The experiments were performed with 1) broiler chickens in floor pens until slaughter 42 d of age, challenge was performed on d 3, 7, or 14 with 2 x 10(6) cfu per chick, and 2) Single Comb White Leghorn chickens in cages until 28 d of age, challenge was performed on d 7 with 10(8) cfu per chick. The inclusion of Toyocerin in feed of inoculated broiler chickens did significantly (P < 0.05) improve ADG (by 3.4 g), BW (by 141 g), and feed conversion ratio (by -0.060 kg/kg) at the end of the trial at 42 d compared with inoculated and untreated birds. At the end of the trial at 42 d, the slaughter age, 42% of untreated birds were still positive for Salmonella, whereas Salmonella was not detected in Toyocerin-treated birds. In Leghorn chickens, at 3 wk after inoculation (the end of the trial), only 38% of birds from the Toyocerin-treated groups were Salmonella-positive, whereas 63% of birds were still Salmonella-positive in the untreated control treatment. No significant differences were detected in performance variables in Leghorn chickens. The results of the present experiments indicate that feeding Toyocerin reduced the prevalence of Salmonella in poultry and in the case of broiler chickens also significantly improved performance variables at slaughter age.


Assuntos
Bacillus cereus/classificação , Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Salmonelose Animal/prevenção & controle , Salmonella enteritidis , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas , Dieta/veterinária , Feminino , Masculino , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia
11.
Parkinsonism Relat Disord ; 66: 151-157, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31409572

RESUMO

OBJECTIVE: To identify factors related to a poor health-related and global quality of life (QoL) in a cohort of non-demented Parkinson's disease (PD) patients and compare to a control group. METHODS: The data correspond to the baseline evaluation of the COPPADIS-2015 Study, an observational, 5-year follow-up, multicenter, evaluation study. Three instruments were used to assess QoL: (1) the 39-item Parkinson's disease Questionnaire (PDQ-39), (2) a subjective rating of global QoL (PQ-10), and (3) the EUROHIS-QOL 8-item index (EUROHIS-QOL8). Multiple linear regression methods were used to evaluate the direct impact of different variables on these QoL measures. RESULTS: QoL was worse in PD patients (n = 692; 62.6 ±â€¯8.9 years old, 60.3% males) than controls (n = 206; 61 ±â€¯8.3 years old, 49.5% males): PDQ-39, 17.1 ±â€¯13.5 vs 4.4 ±â€¯6.3 (p < 0.0001); PQ-10, 7.3 ±â€¯1.6 vs 8.1 ±â€¯1.2 (p < 0.0001); EUROHIS-QOL8, 3.8 ±â€¯0.6 vs 4.2 ±â€¯0.5 (p < 0.0001). A high correlation was observed between PDQ-39 and Non-Motor Symptoms Scale (NMSS) (r = 0.72; p < 0.0001), and PDQ-39 and Beck Depression Inventory-II (BDI-II) (r = 0.65; p < 0.0001). For health-related QoL (PDQ-39), non-motor symptoms burden (NMSS), mood (BDI-II), and gait problems (Freezing Of Gait Questionnaire [FOGQ]) provided the highest contribution to the model (ß = 0.32, 0.28, and 0.27, respectively; p < 0.0001); whereas mood and gait problems contributed the most to global QoL (PQ-10, ß = -0.46 and -0.21, respectively; EUROHIS-QOL8, ß = -0.44 and -0.23, respectively). CONCLUSIONS: QoL is worse in PD patients than in controls. Mood, non-motor symptoms burden, and gait problems seem to be the most relevant factors affecting health-related and global perceived QoL in non-demented PD patients.


Assuntos
Sintomas Afetivos/fisiopatologia , Transtornos Neurológicos da Marcha/fisiopatologia , Doença de Parkinson/fisiopatologia , Qualidade de Vida , Sintomas Afetivos/etiologia , Idoso , Feminino , Seguimentos , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Índice de Gravidade de Doença
12.
Nonlinear Dynamics Psychol Life Sci ; 12(2): 153-61, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18384714

RESUMO

Nonlinear dimensional analyses can be a useful tool in understanding the underlying behavior of dynamical systems, including biological systems. Many biological functions can be modeled as chaotic processes, including sleep. Sleep data can be obtained from several methods, such as electroencephalograms, polysomnography, and actigraph. Actigraphy, because of its low level of invasiveness, is an increasingly popular method of obtaining sleep data. This study analyzed actigraphy data with nonlinear dimensional analyses to determine if such analytic methods would be useful in sleep studies. Participants wore actigraphs on their wrists, which recorded movement for several days. Several sleep quality variables, such as movement during sleep and total sleep time, were derived from these sleep data. These variables were used to determine whether the quality of sleep was good or poor. Lagged phase space plots were graphed and nonlinear parameters for the fractal dimension and the correlation dimension were computed for each participant. Descriptive and inferential statistics were performed to determine if the nonlinear parameters showed significant differences with respect to sleep quality.


Assuntos
Monitorização Ambulatorial/estatística & dados numéricos , Atividade Motora , Dinâmica não Linear , Polissonografia/normas , Adulto , Feminino , Fractais , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Polissonografia/instrumentação , Vigília
13.
Chemosphere ; 67(2): 276-84, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17156816

RESUMO

The effects of water deficit stress and plant water potential (psi) on monoterpene and sesquiterpene leaf emissions from Rosmarinus officinalis, Pinus halepensis, Cistus albidus and Quercus coccifera were studied over 11 days of water withholding (from t(1) to t(11)), after substrates had achieved their field capacity (control pots: t(0)). Volatile compounds were sampled from the same twig per plant all throughout the study, using a dynamic bag enclosure system. Volatiles, collected in Tenax TA, were studied by means of GC-FID and GC-MS. Monoterpene emissions of water stressed plants (t(1)-t(11)) were either similar to those of control seedlings (R. officinalis and Q. coccifera) or higher (P. halepensis and C. albidus). By contrast, sesquiterpene emissions were strongly reduced or inhibited after four days of water withholding, particularly for R. officinalis, thus altering terpene emission composition. Despite the positive effect of water stress on leaf monoterpene emissions of P. halepensis and C. albidus, the significant correlation between these emissions and psi showed a slow decrease of these emissions over long term water deficit periods. This contrasted with the rapid decline of sesquiterpene emissions of R. officinalis according to lower values of psi. These results provide an overall picture of the different responses of monoterpene and sesquiterpene emissions to progressive water loss. They also reveal the utility of using psi for estimating some emission rates of some species according to drought conditions.


Assuntos
Cistus/fisiologia , Pinus/fisiologia , Quercus/fisiologia , Rosmarinus/fisiologia , Sesquiterpenos/metabolismo , Terpenos/metabolismo , Árvores/fisiologia , Água
14.
Comput Methods Biomech Biomed Engin ; 20(14): 1543-1553, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29017357

RESUMO

We propose a fully automated methodology for hexahedral meshing of patient-specific structures of the human knee obtained from magnetic resonance images, i.e. femoral/tibial cartilages and menisci. We select eight patients from the Osteoarthritis Initiative and validate our methodology using MATLAB on a laptop computer. We obtain the patient-specific meshes in an average of three minutes, while faithfully representing the geometries with well-shaped elements. We hope to provide a fundamentally different means to test hypotheses on the mechanisms of disease progression by integrating our patient-specific FE meshes with data from individual patients. Download both our meshes and software at http://im.engr.uconn.edu/downloads.php .


Assuntos
Cartilagem/patologia , Articulação do Joelho/patologia , Osteoartrite/patologia , Automação , Fêmur/patologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Meniscos Tibiais/patologia
15.
J Biomech ; 56: 1-9, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28318603

RESUMO

Accurate estimation of peak wall stress (PWS) is the crux of biomechanically motivated rupture risk assessment for abdominal aortic aneurysms aimed to improve clinical outcomes. Such assessments often use the finite element (FE) method to obtain PWS, albeit at a high computational cost, motivating simplifications in material or element formulations. These simplifications, while useful, come at a cost of reliability and accuracy. We achieve research-standard accuracy and maintain clinically applicable speeds by using novel computational technologies. We present a solution using our custom finite element code based on graphics processing unit (GPU) technology that is able to account for added complexities involved with more physiologically relevant solutions, e.g. strong anisotropy and heterogeneity. We present solutions up to 17× faster relative to an established finite element code using state-of-the-art nonlinear, anisotropic and nearly-incompressible material descriptions. We show a realistic assessment of the explicit GPU FE approach by using complex problem geometry, biofidelic material law, double-precision floating point computation and full element integration. Due to the increased solution speed without loss of accuracy, shown on five clinical cases of abdominal aortic aneurysms, the method shows promise for clinical use in determining rupture risk of abdominal aortic aneurysms.


Assuntos
Aneurisma da Aorta Abdominal , Ruptura Aórtica , Análise de Elementos Finitos , Humanos , Modelos Cardiovasculares , Reprodutibilidade dos Testes , Risco , Estresse Mecânico
16.
Physiol Meas ; 27(4): 413-23, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16537982

RESUMO

Accelerometer data quality can be inadequate due to data corruption or to non-compliance of the subject with regard to study protocols. We propose a simple statistical test to determine if accelerometer data are of good quality and can be used for analysis or if the data are of poor quality and should be discarded. We tested several data evaluation methods using a group of 105 subjects who wore Motionlogger actigraphs (Ambulatory Monitoring, Inc.) over a 15 day period to assess sleep quality in a study of health outcomes associated with stress among police officers. Using leave-one-out cross-validation and calibration-testing methods of discrimination statistics, error rates for the methods ranged from 0.0167 to 0.4046. We found that the best method was to use the overall average distance between consecutive time points and the overall average mean amplitude of consecutive time points. These values gave us a classification error rate of 0.0167. The average distance between points is a measure of smoothness in the data, and the average mean amplitude between points gave an average reading. Both of these values were then normed to determine a final statistic, K, which was then compared to a cut-off value, K(C), to determine data quality.


Assuntos
Aceleração , Monitorização Ambulatorial/instrumentação , Atividade Motora/fisiologia , Algoritmos , Automação , Calibragem , Interpretação Estatística de Dados , Humanos , Polícia , Reprodutibilidade dos Testes , Sono/fisiologia , Estresse Psicológico/fisiopatologia
17.
Nutr Hosp ; 20(2): 93-100, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15813392

RESUMO

Enteral nutrition has demonstrated to be a useful and safe method to nourish critically ill patients admitted to the Intensive Care Unit. Although the time a severely ill patient can stand without nutrition is unknown, accelerated catabolism and fasting may be deleterious in those patients, and the more common recommendation is to start on artificial nutrition when a fasting period longer than seven days is foreseen. At an experimental level, advantages of enteral nutrition over parenteral nutrition are evident since the use of nutritional substrates via the gastrointestinal tract improves the local and systemic immune response and maintains the barrier functions of the gut. Clinical studies have demonstrated that early enteral nutrition administered within the first 48 hours of admission decreases the incidence of nosocomial infections in these patients, but not the mortality, with the exception of special groups of patients, particularly surgical ones. The major inconvenience of enteral nutrition is its digestive intolerance and the transpyloric approach, necessary when there is gastroparesia. Its efficacy is also questioned when the patient has tissue ischemia. For early enteral nutrition to be effective, a treatment strategy must be implemented that includes from simple measures, such as uprising the bed headrest, to more sophisticated ones, such as the transpyloric approach or the use of nutrients with immunomodulatory capabilities. To date, the use of early enteral nutrition is the best method for nutritional support in this kind of patients provided that it is individualized according to each patient clinical status and that is done following an adequate therapeutic strategy.


Assuntos
Estado Terminal/terapia , Nutrição Enteral , Humanos , Índice de Gravidade de Doença , Fatores de Tempo
18.
J Anim Sci ; 93(1): 238-46, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25568372

RESUMO

Salmonella enterica serovar Enteritidis is one of the leading causes of food-borne salmonellosis in humans. Poultry is the single largest reservoir, and the consumption of incorrectly processed chicken meat and egg products is the major source of infection. Since 2006, the use of antibiotics as growth promoters has been banned in the European Union, and the dietary inclusion of ß-galactomannans (ßGM) has become a promising strategy to control and prevent intestinal infections. The aim of this study was to investigate the effect of various ßGM-rich products on intestinal morphology in chickens challenged with Salmonella Enteritidis. To assess this effect, a total of 280 male Ross 308 chickens were studied (40 animals per treatment housed in 5 cages). There were 7 treatments, including controls: uninoculated birds fed the basal diet (negative control) and inoculated birds fed the basal diet (positive control) or the basal diet supplemented with Salmosan (1 g/kg), Duraió gum (1 g/kg), Cassia gum (1 g/kg), the cell walls of Saccharomyces cerevisiae (0.5 g/kg), or the antibiotic colistine (0.8 g/kg). The birds were fed these diets from the d 1 to 23, except the animals in the colistine group, which were fed the diet containing the antibiotic only from d 5 to 11. The inoculated animals were orally infected on d 7 with 10(8) cfu of Salmonella Enteritidis. Bird performance per replicate was determined for the whole study period (23 d), and the distal ileum and cecal tonsil of 5 animals per treatment (1 animal per replicate) were observed at different magnification levels (scanning electron, light, and laser confocal microscopy). In the images corresponding to the treatments containing ßGM we observed more mucus, an effect that can be associated with the observation of more goblet cells. Moreover, the images also show fewer M cells, which are characteristic of infected animals. Regarding the morphometric parameters, the animals that received Duraió and Cassia gums show greater (P = 0.001 and P = 0.016, respectively) villus length compared with the animals in the positive control, thus indicating the capacity of these products to increase epithelial surface area. However, no effect (P > 0.05) on microvillus dimensions was detected. In conclusion, the results obtained indicating the beneficial effects of these ßGM on intestinal morphology give more evidence of the positive effects of these supplements in poultry nutrition.


Assuntos
Galinhas/microbiologia , Dieta/veterinária , Enterite/veterinária , Intestinos/efeitos dos fármacos , Mananas/farmacologia , Doenças das Aves Domésticas/patologia , Salmonelose Animal/patologia , Salmonella enteritidis , Ração Animal , Animais , Antibacterianos/farmacologia , Ceco/efeitos dos fármacos , Ceco/microbiologia , Ceco/patologia , Colistina/farmacologia , Suplementos Nutricionais , Enterite/microbiologia , Enterite/patologia , Galactose/análogos & derivados , Humanos , Íleo/efeitos dos fármacos , Íleo/microbiologia , Íleo/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Intestinos/microbiologia , Intestinos/patologia , Masculino , Mananas/administração & dosagem , Microvilosidades/efeitos dos fármacos , Microvilosidades/microbiologia , Microvilosidades/ultraestrutura , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/isolamento & purificação
19.
Comput Math Methods Med ; 2015: 202539, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26236390

RESUMO

A correct patient-specific identification of the abdominal aortic aneurysm is useful for both diagnosis and treatment stages, as it locates the disease and represents its geometry. The actual thickness and shape of the arterial wall and the intraluminal thrombus are of great importance when predicting the rupture of the abdominal aortic aneurysms. The authors describe a novel method for delineating both the internal and external contours of the aortic wall, which allows distinguishing between vessel wall and intraluminal thrombus. The method is based on active shape model and texture statistical information. The method was validated with eight MR patient studies. There was high correspondence between automatic and manual measurements for the vessel wall area. Resulting segmented images presented a mean Dice coefficient with respect to manual segmentations of 0.88 and a mean modified Hausdorff distance of 1.14 mm for the internal face and 0.86 and 1.33 mm for the external face of the arterial wall. Preliminary results of the segmentation show high correspondence between automatic and manual measurements for the vessel wall and thrombus areas. However, since the dataset is small the conclusions cannot be generalized.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/patologia , Vasos Sanguíneos/patologia , Endotélio Vascular/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Trombose/patologia , Algoritmos , Angiografia , Fenômenos Biomecânicos , Humanos , Imageamento Tridimensional , Modelos Estatísticos , Reprodutibilidade dos Testes , Software , Trombose/diagnóstico , Tomografia Computadorizada por Raios X
20.
Food Chem Toxicol ; 40(4): 479-86, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11893407

RESUMO

The effects of an acute administration of T-2 toxin on vitamin E status and the corresponding degree of lipid peroxidation, as determined by the plasma and organ content of malondialdehyde (MDA), was studied in mice. The effects of T-2 toxin administration on the body weight and weights of liver, spleen and thymus were also assessed. T-2 toxin was administered in doses ranging from 1 to 6.25 mg/kg body weight, depending on the experiment, while the dietary content of vitamin E ranged from near 0 to 5000 IU/kg. There was a significant decrease in vitamin E content of plasma after the administration of the toxin with the concentrations remaining low for periods as long as 48-72 h. MDA content of liver increased significantly after 24-48 h of toxin administration in contrast to the controls. However, MDA levels returned to the control range after 72 h. The concentrations of MDA in liver were inversely related to the vitamin E content of the diet, and were always higher for the toxin-treated animals (significant linear regression between MDA content of liver and the log10 of vitamin E content of the diet). Weights of spleen and thymus decreased after T-2 toxin administration; however, the weight of liver either increased or did not change in the different experiments. In conclusion, T-2 toxin treatment of mice increased lipid peroxidation in the liver as measured by MDA production. This process was maximal after 48 h of T-2 challenge, and decreased thereafter. Plasma alpha-tocopherol levels decreased as soon as 6 h after the toxin challenge, while MDA did not increase until there was a severe depletion of vitamin E. These changes were accompanied by decrease in weight of spleen and thymus.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Toxina T-2/efeitos adversos , Administração Oral , Animais , Peso Corporal , Relação Dose-Resposta a Droga , Feminino , Fígado/patologia , Camundongos , Baço/patologia , Timo/patologia , Vitamina E/sangue , Vitamina E/metabolismo
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