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1.
Int J Geriatr Psychiatry ; 34(12): 1892-1899, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31469190

RESUMO

OBJECTIVES: Little research has explored how cognitive function and activities of daily living (ADL) affect each other over time. In addition, no current finding provides a clear hint to the temporal precedence between them. The present study tries to address these limitations of prior studies by utilizing a longitudinal data and advanced statistical modeling. METHODS: This study analyzed the data from the China Health and Retirement Longitudinal Study (CHARLS), a prospective observational study performed every 2 years for a total of three waves between 2011 and 2015 using a multistage probability sampling. Cognitive function was measured on the basis of three aspects of cognitive performance. Functional abilities were assessed using six types of activities of ADL and five types of instrumental ADL (IADL). Latent difference score modeling was employed to investigate the temporal precedence between cognitive function and ADL. RESULTS: The best fitting model indicates poor cognitive function precede worsening in ADL function, whereas the current findings did not support that poor ADL predate the cognition decline or reciprocal influence hypotheses. CONCLUSIONS: The elderly with poor cognitive function may be more vulnerable to deterioration in ADL. Findings underscore the importance of early screening for cognitive function among the elderly as the key strategy to prevent further ADL impairment and keep independence.


Assuntos
Atividades Cotidianas/psicologia , Cognição/fisiologia , Disfunção Cognitiva/complicações , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Vida Independente , Estudos Longitudinais , Masculino , Estudos Prospectivos
2.
Exp Cell Res ; 369(2): 275-283, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29842876

RESUMO

BACKGROUND/OBJECTIVE: Vascular endothelial growth factor (VEGF) has been recognized to be a potential pharmaceutical target for treating ischemic stroke, but its severe side effects hinder its widely application. Here, the present study was designed to investigate the effects of VEGF on blood-brain-barrier (BBB) disruption and the underlying mechanisms. METHODS: A mouse model of middle cerebral artery occlusion (MCAO) was constructed and treated with or without VEGF. Meanwhile, mice brain microvascular endothelial cells in co-culture with astrocytes were subjected to 1, 2 and 4 h oxygen-glucose deprivation followed by 24 h of reperfusion (OGD/R) in the absence or presence of VEGF. The mRNA and protein expression were assessed by real-time PCR and Western blotting. Fluorescence in situ hybridization (FISH) was utilized to validate LOC102640519 expression in OGD/R cell models. Chromatin Immunoprecipitation (ChIP) assay was used to confirm the regulatory mechanism of LOC102640519 to HOXC13. Interactions between HOXC13 and ZO-1 were measured by a luciferase reporter assay and RNA pull down assay. RESULTS: Our results showed that administration of VEGF significantly aggravated BBB by upregulating LOC102640519 and HOXC13 expression in vitro and vitro model of cerebral ischemia. Furthermore, LOC102640519 positively regulated the expression of HOXC13, thus negatively regulated the expression of ZO-1, Occludin and Claudin-5 in OGD/R model in the absence or presence of VEGF. CONCLUSIONS: VEGF aggravated BBB disruption after cerebral I/R-induced injury probably by increasing LOC102640519 and HOXC13 through inhibition of ZO-1, Occludin and Claudin-5.


Assuntos
Barreira Hematoencefálica/metabolismo , Isquemia Encefálica/etiologia , Isquemia Encefálica/metabolismo , Proteínas de Homeodomínio/metabolismo , RNA Longo não Codificante/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/genética , Células Cultivadas , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas de Homeodomínio/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/genética , Traumatismo por Reperfusão/genética , Transdução de Sinais , Proteínas de Junções Íntimas/genética , Proteínas de Junções Íntimas/metabolismo , Regulação para Cima , Proteína da Zônula de Oclusão-1/genética
3.
Clin Exp Hypertens ; 41(6): 516-523, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30199277

RESUMO

Researches involving arterial pressure measurements in mice have primarily relied on carotid arterial catheterization. However, in some circumstances, measuring arterial pressure through the carotid arterial impairs accuracy. This study was aimed to evaluate whether femoral artery could displace carotid artery for the blood pressure (BP) measurements in mice. Fifty-six Swiss mice (n = 14 in each group) were randomized into four groups: control, left femoral artery, right femoral artery, and union group, in which BP was measured through left carotid, left femoral, right femoral artery, and simultaneously from right femoral artery and left carotid artery, respectively. Arterial pressure was recorded for 5 min after catheterization. There was no significant difference of the success rate and mortality rate among four groups (P > 0.05), and no obvious difference (P > 0.05) of catheterization time among the first three groups. For intergroup comparison of arterial pressure, there was no significant difference (P > 0.05) of the systolic blood pressure (SBP), diastolic BP, mean arterial pressure, and pulse pressure among the first three groups. For intragroup comparison, SBP, diastolic blood pressure (DBP), mean arterial pressure (MAP) monitored from right femoral artery were similar (P > 0.05) with those from left carotid artery, with significantly positive correlation. The mean values of difference of SBP, DBP, and MAP were -1.3, 1.2, and 0.5 mmHg, respectively. Our results indicated that femoral artery catheterization could be a safe, feasible, reliable, and accuracy alternative for the direct measurement of arterial pressure in anesthesia mice.


Assuntos
Pressão Arterial/fisiologia , Artérias Carótidas/fisiopatologia , Artéria Femoral/fisiologia , Hipertensão/fisiopatologia , Monitorização Fisiológica/métodos , Animais , Determinação da Pressão Arterial/métodos , Cateterismo Periférico , Modelos Animais de Doenças , Hipertensão/diagnóstico , Masculino , Camundongos
4.
Opt Express ; 26(18): 22837-22856, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184942

RESUMO

An FTIR spectrometer often suffers from common problems of band overlap and Poisson noises. In this paper, we show that the issue of infrared (IR) spectrum degradation can be considered as a maximum a posterior (MAP) problem and solved by minimized a cost function that includes a likelihood term and two prior terms. In the MAP framework, the likelihood probability density function (PDF) is constructed based on the observed Poisson noise model. A fitted distribution of curvelet transform coefficient is used as spectral prior PDF, and the instrument response function (IRF) prior is described based on a Gauss-Markov function. Moreover, the split Bregman iteration method is employed to solve the resulting minimization problem, which highly reduces the computational load. As a result, the Poisson noises are perfectly removed, while the spectral structure information is well preserved. The novelty of the proposed method lies in its ability to estimate the IRF and latent spectrum in a joint framework, thus eliminating the degradation effects to a large extent. The reconstructed IR spectrum is more convenient for extracting the spectral feature and interpreting the unknown chemical or biological materials.

5.
Opt Express ; 26(26): 33510-33522, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650798

RESUMO

The phase measurement deflectometry considering the refraction effect is presented to measure the mirror surface in this paper. In the context of the conventional phase measurement deflectometry, the biplanar structure of the system constructed by spatial multiplexing of a screen or a half mirror with two screens is a compromise of traditional display technology, while they suffer from complex calibration process and low accuracy. To improve the system compactness and efficiency, a novel measurement model consisting of a transparent screen and an ordinary screen is used to determine the incident light. To compensate for the measurement errors caused by transparent screen refraction, the refraction of the transparent screen is characterized by two physical parameters, which can be calibrated thanks to the multi-stereo vision technique. Then, the improved mirror calibration method with the refraction model is proposed to determine the posed relationship of the system. After that, the three-dimensional (3D) information of mirror surface is restored by the radial basis function interpolation with the optimized refraction parameters and posed relationships from the gradient data which is transformed from the normal information. Higher measurement efficiency, higher measurement accuracy and more compactness of the proposed measurement method are verified by the experimental results.

6.
Appl Opt ; 54(23): 6969-78, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26368363

RESUMO

Catadioptric omnidirectional images exhibit serious nonlinear distortion due to the involved quadratic mirror. Conventional pinhole model-based methods perform poorly when directly applied to the deformed omnidirectional images. This study constructs a catadioptric geometry system to analyze the variation of the neighborhood of an object in terms of the elevation and azimuth directions in a spherical coordinate system. To accurately represent the distorted visual information, a parametric neighborhood mapping model is proposed based on the catadioptric geometry. Unlike the conventional catadioptric models, the prior information of the system is effectively integrated into the neighborhood formulation framework. Then the distortion-adaptive neighborhood can be directly calculated based on its measurable image radial distance. This method can significantly improve the computational efficiency of algorithm since statistical neighborhood sampling is not used. On the basis of the proposed neighborhood model, a distortion-invariant Haar wavelet transform is presented to perform the robust human detection and tracking in catadioptric omnidirectional vision. The experimental results verify the effectiveness of the proposed neighborhood mapping model and prove that the distorted neighborhood in the omnidirectional image follows a nonlinear pattern.


Assuntos
Lentes , Óptica e Fotônica , Visão Ocular , Algoritmos , Inteligência Artificial , Desenho de Equipamento , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Modelos Teóricos , Reconhecimento Automatizado de Padrão/métodos , Probabilidade , Software
7.
Sensors (Basel) ; 15(12): 30240-60, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26633422

RESUMO

Tracking multiple moving targets from a video plays an important role in many vision-based robotic applications. In this paper, we propose an improved Gaussian mixture probability hypothesis density (GM-PHD) tracker with weight penalization to effectively and accurately track multiple moving targets from a video. First, an entropy-based birth intensity estimation method is incorporated to eliminate the false positives caused by noisy video data. Then, a weight-penalized method with multi-feature fusion is proposed to accurately track the targets in close movement. For targets without occlusion, a weight matrix that contains all updated weights between the predicted target states and the measurements is constructed, and a simple, but effective method based on total weight and predicted target state is proposed to search the ambiguous weights in the weight matrix. The ambiguous weights are then penalized according to the fused target features that include spatial-colour appearance, histogram of oriented gradient and target area and further re-normalized to form a new weight matrix. With this new weight matrix, the tracker can correctly track the targets in close movement without occlusion. For targets with occlusion, a robust game-theoretical method is used. Finally, the experiments conducted on various video scenarios validate the effectiveness of the proposed penalization method and show the superior performance of our tracker over the state of the art.


Assuntos
Inteligência Artificial , Processamento de Imagem Assistida por Computador/métodos , Robótica/métodos , Gravação em Vídeo/métodos , Algoritmos , Rastreamento de Células , Humanos , Modelos Teóricos , Movimento , Distribuição Normal
8.
Blood ; 119(17): 4066-72, 2012 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-22294727

RESUMO

The effects of eltrombopag, a thrombopoietin-receptor agonist, on platelet function in immune thrombocytopenia (ITP) are not fully characterized. This study used whole blood flow cytometry to examine platelet function in 20 patients receiving eltrombopag treatment at days 0, 7, and 28. Platelet surface expression of activated GPIIb/IIIa, P-selectin, and GPIb was measured with and without low and high adenosine diphosphate (ADP) and thrombin receptor activating peptide (TRAP) concentrations. Before eltrombopag treatment with no ex vivo agonist, platelet activation was higher in ITP patients than controls. Platelet GPIb and activated GPIIb/IIIa expression without added agonist was unchanged following eltrombopag treatment, whereas a slight increase in P-selectin was observed. Expression of P-selectin and activated GPIIb/IIIa in response to high-dose ADP was lower during eltrombopag treatment than at baseline. Eltrombopag led to a slight increase in platelet reactivity to TRAP only in responders to eltrombopag but not to levels above those in controls; whole blood experiments demonstrated that this increase was probably because of higher platelet counts rather than higher platelet reactivity. In conclusion, although thrombocytopenic ITP patients have higher baseline platelet activation than controls, eltrombopag did not cause platelet activation or hyper-reactivity, irrespective of whether the platelet count increased.


Assuntos
Benzoatos/uso terapêutico , Plaquetas/efeitos dos fármacos , Hidrazinas/uso terapêutico , Ativação Plaquetária/efeitos dos fármacos , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/metabolismo , Pirazóis/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Selectina-P/metabolismo , Fragmentos de Peptídeos/farmacologia , Contagem de Plaquetas , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Púrpura Trombocitopênica Idiopática/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
J Vasc Surg ; 57(2): 354-61, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23182157

RESUMO

OBJECTIVE: Scoring systems for predicting mortality after repair of ruptured abdominal aortic aneurysms (RAAAs) have not been developed or tested in a United States population and may not be accurate in the endovascular era. Using prospectively collected data from the Vascular Study Group of New England (VSGNE), we developed a practical risk score for in-hospital mortality after open repair of RAAAs and compared its performance to that of the Glasgow aneurysm score, Hardman index, Vancouver score, and Edinburg ruptured aneurysm score. METHODS: Univariate analysis followed by multivariable analysis of patient, prehospital, anatomic, and procedural characteristics identified significant predictors of in-hospital mortality. Integer points were derived from the odds ratio (OR) for mortality based on each independent predictor in order to generate a VSGNE RAAA risk score, which was internally validated using bootstrapping methodology. Discrimination and calibration of all models were assessed by calculating the area under the receiver-operating characteristic curve (C-statistic) and applying the Hosmer-Lemeshow test. RESULTS: From 2003 to 2009, 242 patients underwent open repair of RAAAs at 10 centers. In-hospital mortality was 38% (n = 91). Independent predictors of mortality included age >76 years (OR, 5.3; 95% confidence interval [CI], 2.8-10.1), preoperative cardiac arrest (OR, 4.3; 95% CI, 1.6-12), loss of consciousness (OR, 2.6; 95% CI, 1.2-6), and suprarenal aortic clamp (OR, 2.4; 95% CI, 1.3-4.6). Patient stratification according to the VSGNE RAAA risk score (range, 0-6) accurately predicted mortality and identified those at low and high risk for death (8%, 25%, 37%, 60%, 80%, and 87% for scores of 0, 1, 2, 3, 4, and ≥5, respectively). Discrimination (C = .79) and calibration (χ(2) = 1.96; P = .85) were excellent in the derivation and bootstrap samples and superior to that of existing scoring systems. The Glasgow aneurysm score, Hardman index, Vancouver score, and Edinburg ruptured aneurysm score correlated with mortality in the VSGNE cohort but failed to identify accurately patients with a risk of mortality >65%. CONCLUSIONS: Existing scoring systems predict mortality after RAAA repair in this cohort but do not identify patients at highest risk. This parsimonious VSGNE RAAA risk score based on four variables readily assessed at the time of presentation allows accurate prediction of in-hospital mortality after open repair of RAAAs, including identification of those patients at highest risk for postoperative mortality.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/cirurgia , Técnicas de Apoio para a Decisão , Indicadores Básicos de Saúde , Procedimentos Cirúrgicos Vasculares/mortalidade , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/mortalidade , Ruptura Aórtica/mortalidade , Distribuição de Qui-Quadrado , Análise Discriminante , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , New England/epidemiologia , Razão de Chances , Seleção de Pacientes , Curva ROC , Sistema de Registros , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos
10.
Adv Clin Exp Med ; 32(4): 415-422, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36449399

RESUMO

BACKGROUND: Severe traumatic brain injuries (STBIs) cause 1/3-1/2 of trauma-related deaths. Tumor necrosis factor (TNF) receptor-associated factor NF-κB activator (TANK)-binding kinase 1 (TBK1) is a biomarker associated with inflammation, while inflammation is a key promoter of the TBI process. OBJECTIVES: To investigate the clinical significance of TBK1 in STBI patients. MATERIAL AND METHODS: The present prospective observational study included a total of 95 STBI cases diagnosed from October 2019 to October 2021. The values for optic nerve sheath diameter (ONSD) were determined under deep sedation using 2-dimensional gray scale ultrasound. Intracranial pressure (ICP) was also measured. Serum levels of TBK1 and inflammatory factors such as C-reactive protein (CRP), interleukin (IL)-1ß and IL-6 were evaluated with enzyme-linked immunosorbent assay (ELISA). Clinical variables including pathological type, Glasgow Coma Scale (GCS) score, sequential organ failure assessment (SOFA) score, and Acute Physiology and Chronic Health Evaluation II (APACHE II) score were recorded. RESULTS: The levels of TBK1 in the deceased patients were remarkably lower than in the patients who survived. The IL-1ß and IL-6 were markedly elevated in deceased patients compared with survivors, and negatively correlated with serum levels of TBK1. The ONSD and ICP values were significantly higher in the deceased patients than in the patients who survived and were positively correlated with each other, while both were negatively correlated with TBK1 levels. Patients with lower TBK1 expression showed significantly lower GCS scores, higher SOFA and APACHE II scores, as well as a higher 1-month mortality rate. The Kaplan-Meier curve showed that patients with higher TBK1 levels had a higher 1-month survival rate compared with the patients with lower TBK1 levels. Only TBK1 and ONSD were independent risk factors for 1-month mortality in STBI patients. CONCLUSIONS: Lower serum TBK1 levels are associated with higher inflammatory factors, higher ONSD and ICP levels, as well as a poorer prognosis in STBI patients.


Assuntos
Lesões Encefálicas Traumáticas , Sedação Profunda , Humanos , Pressão Intracraniana/fisiologia , Interleucina-6 , Inflamação , Nervo Óptico , Proteínas Serina-Treonina Quinases
11.
IEEE Trans Image Process ; 32: 6289-6302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37963008

RESUMO

Head pose estimation (HPE) is an indispensable upstream task in the fields of human-machine interaction, self-driving, and attention detection. However, practical head pose applications suffer from several challenges, such as severe occlusion, low illumination, and extreme orientations. To address these challenges, we identify three cues from head images, namely, critical minority relationships, neighborhood orientation relationships, and significant facial changes. On the basis of the three cues, two key insights on head poses are revealed: 1) intra-orientation relationship and 2) cross-orientation relationship. To leverage two key insights above, a novel relationship-driven method is proposed based on the Transformer architecture, in which facial and orientation relationships can be learned. Specifically, we design several orientation tokens to explicitly encode basic orientation regions. Besides, a novel token guide multi-loss function is accordingly designed to guide the orientation tokens as they learn the desired regional similarities and relationships. Experimental results on three challenging benchmark HPE datasets show that our proposed TokenHPE achieves state-of-the-art performance. Moreover, qualitative visualizations are provided to verify the effectiveness of the token-learning methodology.


Assuntos
Sinais (Psicologia) , Aprendizagem , Humanos , Benchmarking , Face/diagnóstico por imagem , Iluminação
12.
Front Bioeng Biotechnol ; 11: 1244550, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849981

RESUMO

Robot-assisted rehabilitation has exhibited great potential to enhance the motor function of physically and neurologically impaired patients. State-of-the-art control strategies usually allow the rehabilitation robot to track the training task trajectory along with the impaired limb, and the robotic motion can be regulated through physical human-robot interaction for comfortable support and appropriate assistance level. However, it is hardly possible, especially for patients with severe motor disabilities, to continuously exert force to guide the robot to complete the prescribed training task. Conversely, reduced task difficulty cannot facilitate stimulating patients' potential movement capabilities. Moreover, challenging more difficult tasks with minimal robotic assistance is usually ignored when subjects show improved performance. In this paper, a control framework is proposed to simultaneously adjust both the training task and robotic assistance according to the subjects' performance, which can be estimated from the users' electromyography signals. Concretely, a trajectory deformation algorithm is developed to generate smooth and compliant task motion while responding to pHRI. An assist-as-needed (ANN) controller along with a feedback gain modification algorithm is designed to promote patients' active participation according to individual performance variance on completing the training task. The proposed control framework is validated using a lower extremity rehabilitation robot through experiments. The experimental results demonstrate that the control scheme can optimize the robotic assistance to complete the subject-adaptation training task with high efficiency.

13.
J Vasc Surg ; 56(2): 353-60, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22480762

RESUMO

INTRODUCTION: To date, history of a contralateral amputation as a potential predictor of outcomes after lower extremity bypass (LEB) for critical limb ischemia (CLI) has not been studied. We sought to determine if a prior contralateral lower extremity amputation predicts worse outcomes in patients undergoing LEB in the remaining intact limb. METHODS: A retrospective analysis of all patients undergoing infrainguinal LEB for CLI between 2003 and 2010 within hospitals comprising the Vascular Study Group of New England was performed. Patients were stratified according to whether or not they had previously undergone a contralateral major or minor amputation before LEB. Primary end points included major amputation and graft occlusion at 1 year postoperatively. Secondary end points included in-hospital major adverse events, discharge status, and mortality at 1 year. RESULTS: Of 2636 LEB procedures, 228 (8.6%) were performed in the setting of a prior contralateral amputation. Patients with a prior amputation compared to those without were younger (66.5 vs 68.7; P = .034), more like to have congestive heart failure (CHF; 25% vs 16%; P = .002), hypertension (94% vs 85%; P = .015), renal insufficiency (26% vs 14%; P = .0002), and hemodialysis-dependent renal failure (14% vs 6%; P = .0002). They were also more likely to be nursing home residents (8.0% vs 3.6%; P = .036), less likely to ambulate without assistance (41% vs 80%; P < .0002), and more likely to have had a prior ipsilateral bypass (20% vs 12%; P = .0005). These patients experience increased in-hospital major adverse events, including myocardial infarction (MI; 8.9% vs 4.2%; P = .002), CHF (6.1% vs 3.4%; P = .044), deterioration in renal function (9.0% vs 4.7%; P = .006), and respiratory complications (4.2% vs 2.3%; P = .034). They were less likely to be discharged home (52% vs 72%; P < .0001) and less likely to be ambulatory on discharge (25% vs 55%; P < .0001). Although patients with a prior contralateral amputation experienced increased rates of graft occlusion (38% vs 17%; P < .0001) and major amputation (16% vs 7%; P < .0001) at 1 year, there was not a significant difference in mortality (16% vs 10%; P = .160). On multivariable analysis, prior contralateral amputation was an independent predictor of both major amputation (odds ratio, 1.73; confidence interval, 1.06-2.83; P = .027) and graft occlusion (odds ratio, 1.93; confidence interval, 1.39-2.68; P < .0001) at 1 year. CONCLUSIONS: Patients with prior contralateral amputations who present with CLI in the intact limb represent a high-risk population, even among patients with advanced peripheral arterial disease. When considering LEB in this setting, both physicians and patients should expect increased rates of perioperative adverse events, increased rates of 1-year graft occlusion, and decreased rates of limb salvage, when compared with patients who have not undergone a contralateral amputation.


Assuntos
Amputação Cirúrgica , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Vasculares , Idoso , Feminino , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Masculino , Análise Multivariada , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos
14.
World J Surg ; 36(12): 2909-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22933050

RESUMO

BACKGROUND: Organ shortage is the greatest challenge facing the field of organ transplantation today. Use of more organs of marginal quality has been advocated to address the shortage. METHOD: We examined the pattern of donation and organ use in the United States as shown in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database of individuals who were consented for and progressed to organ donation between January 2001 and December 2010. RESULTS: There were 66,421 living donors and 73,359 deceased donors, including 67,583 (92.1%) identified as donation after brain death and 5,776 (7.9%) as donation after circulatory death (DCD). Comparing two periods, era 1 (01/2001-12/2005) and era 2 (01/2006-12/2010), the number of deceased donors increased by 20.3% from 33,300 to 40,059 while there was a trend for decreasing living donation. The DCD subgroup increased from 4.9 to 11.7% comparing the two eras. A significant increase in cardiovascular/cerebrovascular disease as a cause of death was also noted, from 38.1% in era 1 to 56.1% in era 2 (p<0.001), as was a corresponding decrease in the number of deaths due to head trauma (48.8 vs. 34.9%). The overall discard rate also increased from 13,411 (11.5%) in era 1 to 19,516 (13.7%) in era 2. This increase in discards was especially prominent in the DCD group [440 (20.9%) in era 1 vs. 2,089 (24.9%) in era 2]. CONCLUSIONS: We detect a significant change in pattern of organ donation and use in the last decade in the United States. The transplant community should consider every precaution to prevent the decay of organ quality and to improve the use of marginal organs.


Assuntos
Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Causas de Morte , Bases de Dados Factuais , Seleção do Doador/estatística & dados numéricos , Seleção do Doador/tendências , Humanos , Doadores Vivos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/tendências , Estados Unidos
15.
J Opt Soc Am A Opt Image Sci Vis ; 29(11): 2514-24, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23201815

RESUMO

A central catadioptric-perspective camera system is widely used nowadays. A critical problem is that current calibration methods cannot determine the extrinsic parameters between the central catadioptric camera and a perspective camera effectively. We present a novel calibration method for a central catadioptric-perspective camera system, in which the central catadioptric camera has a hyperbolic mirror. Two cameras are used to capture images of one calibration pattern at different spatial positions. A virtual camera is constructed at the origin of the central catadioptric camera and faced toward the calibration pattern. The transformation between the virtual camera and the calibration pattern could be computed first and the extrinsic parameters between the central catadioptric camera and the calibration pattern could be obtained. Three-dimensional reconstruction results of the calibration pattern show a high accuracy and validate the feasibility of our method.


Assuntos
Dispositivos Ópticos , Calibragem , Processamento de Imagem Assistida por Computador , Modelos Teóricos
16.
J Opt Soc Am A Opt Image Sci Vis ; 29(6): 1047-58, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22673436

RESUMO

Gamma distortion is a dominant error source of phase measuring profilometry. It makes a single frequency for the ideal sinusoidal waveform an infinite width of spectrum. Besides, the defocus of the projector-camera system, like a spatial low-pass filter, attenuates the amplitudes of the high-frequency harmonics. In this paper, a generic distorted fringe model is proposed, which is expressed as a Fourier series. The mathematical model of the harmonic coefficients is derived. Based on the proposed model, a robust gamma calibration method is introduced. It employs the multifrequency phase-shifting method to eliminate the effect of defocus and preserve the influence of gamma distortion. Then, a gamma correction method is proposed to correct the gamma distortion with the calibrated gamma value. The proposed correction method has the advantage of high signal-to-noise ratio. The proposed model is verified through experiments. The results confirm that the phase error is dependent on the defocus and the pitch. The proposed gamma calibration method is compared with the state of the art and proves to be more robust to pitch and defocus variations. After adopting the proposed gamma correction method, the phase precision is much enhanced with higher quality in the measured surfaces.

17.
Appl Opt ; 51(27): 6641-52, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23033037

RESUMO

In this paper, we introduce a novel surveillance system based on thermal catadioptric omnidirectional (TCO) vision. The conventional contour-based methods are difficult to be applied to the TCO sensor for detection or tracking purposes due to the distortion of TCO vision. To solve this problem, we propose a contour coding based rotating adaptive model (RAM) that can extract the contour feature from the TCO vision directly as it takes advantage of the relative angle based on the characteristics of TCO vision to change the sequence of sampling automatically. A series of experiments and quantitative analyses verify that the performance of the proposed RAM-based contour coding feature for human detection and tracking are satisfactory in TCO vision.

18.
Appl Opt ; 51(22): 5340-56, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22859022

RESUMO

Color code is widely employed in coded structured light to reconstruct the three-dimensional shape of objects. Before determining the correspondence, a very important step is to identify the color code. Until now, the lack of an effective evaluation standard has hindered the progress in this unsupervised classification. In this paper, we propose a framework based on the benchmark to explore the new frontier. Two basic facets of the color code identification are discussed, including color feature selection and clustering algorithm design. First, we adopt analysis methods to evaluate the performance of different color features, and the order of these color features in the discriminating power is concluded after a large number of experiments. Second, in order to overcome the drawback of K-means, a decision-directed method is introduced to find the initial centroids. Quantitative comparisons affirm that our method is robust with high accuracy, and it can find or closely approach the global peak.


Assuntos
Cor , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Algoritmos , Inteligência Artificial , Simulação por Computador , Face , Feminino , Mãos , Humanos , Armazenamento e Recuperação da Informação/métodos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão/métodos
19.
HPB (Oxford) ; 14(7): 455-60, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22672547

RESUMO

OBJECTIVES: Living donor liver transplantation (LDLT) is an accepted treatment for patients with end-stage liver disease. To minimize risk to the donor, left lobe (LL) LDLT may be an ideal option in adult LDLT. METHODS: This study assessed the outcomes of LL-LDLT compared with right lobe (RL) LDLT in adults (1998-2010) as reported to the United Network for Organ Sharing (UNOS) Organ Procurement and Transplantation Network (OPTN). RESULTS: A total of 2844 recipients of LDLT were identified. Of these, 2690 (94.6%) underwent RL-LDLT and 154 (5.4%) underwent LL-LDLT. A recent increase in the number of LL-LDLTs was noted: average numbers of LL-LDLTs per year were 5.2 during 1998-2003 and 19.4 during 2004-2010. Compared with RL-LDLT recipients, LL-LDLT recipients were younger (mean age: 50.5 years vs. 47.0 years), had a lower body mass index (BMI) (mean BMI: 24.5 kg/m(2) vs. 26.8 kg/m(2)), and were more likely to be female (64.6% vs. 41.9%). Donors in LL-LDLT had a higher BMI (mean BMI: 29.4 kg/m(2) vs. 26.5 kg/m(2)) and were less likely to be female (30.9% vs. 48.1%). Recipients of LL-LDLT had a longer mean length of stay (24.9 days vs. 18.2 days) and higher retransplantation rates (20.3% vs. 10.9%). Allograft survival in LL-LDLT was significantly lower than in RL-LDLT and there was a trend towards inferior patient survival. In Cox regression analysis, LL-LDLT was found to be associated with an increased risk for allograft failure [hazard ratio (HR): 2.39)] and inferior patient survival (HR: 1.86). CONCLUSIONS: The number of LL-LDLTs has increased in recent years.


Assuntos
Transplante de Fígado/métodos , Doadores Vivos , Adulto , Distribuição de Qui-Quadrado , Feminino , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Sistema de Registros , Reoperação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Obtenção de Tecidos e Órgãos , Resultado do Tratamento , Estados Unidos
20.
J Diabetes Res ; 2022: 4819412, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35127950

RESUMO

BACKGROUND: Pontine infarction is the major subtype of posterior circulation stroke, and diabetes is more common in pontine infarction patients than in anterior circulation stroke patients. Whether the prevalence of diabetes remains homogenous within the posterior circulation stroke population is unclear. The present study is aimed at investigating the prevalence of diabetes in pontine infarction and comparing it to other subtypes of posterior circulation stroke. METHODS: We conducted a multicenter case-control study. Patients with posterior circulation stroke were screened. The subjects were divided into pontine infarction and nonpontine infarction groups. RESULTS: From November 1, 2018, to February 28, 2021, a total of 6145 stroke patients were screened and 2627 patients had posterior circulation strokes. After excluding cardioembolic stroke, as well as its other determined and undetermined causes, 1549 patients with 754 pontine infarctions were included in the analysis. The prevalence of diabetes in the pontine infarction group was higher than that in the nonpontine infarction group (42.7% vs. 31.4%, P < 0.05). After adjusting for confounding factors, diabetes was an independent risk factor for pontine infarction (OR 1.63, 95% CI 1.27-2.09, P < 0.05). For small vessel occlusion, diabetes was also more common in the pontine infarction group (43.2% vs. 30.0%, P < 0.05). Multivariate analysis also showed that diabetes was an independent risk factor for pontine infarction (OR 1.80, 95% CI 1.32-2.46, P < 0.05). CONCLUSION: In comparison with the nonpontine infarction subtype of posterior circulation stroke, patients with pontine infarction had a higher prevalence of diabetes, and diabetes was an independent risk factor for pontine infarction.


Assuntos
Diabetes Mellitus/etiologia , Núcleo Magno da Rafe/anormalidades , Acidente Vascular Cerebral/complicações , Idoso , Estudos de Casos e Controles , China/epidemiologia , Correlação de Dados , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Núcleo Magno da Rafe/irrigação sanguínea , Núcleo Magno da Rafe/lesões , Prevalência , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
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