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1.
Artigo em Inglês | MEDLINE | ID: mdl-36674136

RESUMO

Regional eco-efficiency affects local public health through intermediaries such as economic and environmental impacts. Considering multiple factors, the implicit and uncertain relationship with regional characteristics, and the limited data availability, this paper investigated the forecasting of changes in local public health-including the number of visits to hospitals (VTH), outpatients with emergency treatment (OWET), number of inpatients (NI), number of health examinations (NOHE), and patients discharged (PD)-using calculated regional eco-efficiency with the Least Square-Support Vector Machine-Forecasting Model and acquired empirical evidence, utilizing the province-level data in China. Results: (1) regional eco-efficiency is a good predictor in both a single and multi-factor situation; (2) the prediction accuracy for five dimensions of the changes in local public health was relatively high, and the volatility was lower and more stable throughout the whole forecasting period; and (3) regional heterogeneity, denoted by three economic and demographic factors and three medical supply and technical level factors, improved the forecasting performance. The findings are meaningful for provincial-level decision-makers in China in order for them to know the current status or trends of medical needs, optimize the allocation of medical resources in advance, and enable ample time to tackle urgent emergencies, and, finally, the findings can serve to evaluate the social effects of improving regional eco-efficiency via local enterprises or individuals and adopting sustainable development strategies.


Assuntos
Eficiência , Saúde Pública , Humanos , Aprendizagem , China , Desenvolvimento Econômico
2.
J Surg Res ; 265: 323-332, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33971464

RESUMO

BACKGROUND: Nowadays, there is no approved targeted agent for lung injury induced by sepsis. S1PR2 is confirmed to be a promising diagnosis and treatment target. JTE-013 as S1PR2 antagonists may be an agent of great potential. In this research, we sought to determine the functional role of JTE-013 in lung injury induced by sepsis. MATERIALS AND METHODS: Seventy-two rats were assigned into normal group, sepsis model group and JTE-013 group. The animal model of lung injury induced by sepsis was constructed by cecal ligation and puncture. The human pulmonary microvascular endothelial cells (HPMECs) were divided into control, LPS and LPS + JTE-013 group. HPMECs induced by LPS served as the cell model of lung injury induced by sepsis. HE staining assay was performed for assessment of the pathological condition and Evans blue was applied for assessment of pulmonary tissue permeability. Wet/dry ratio was measured as indicators of pulmonary edema degree and neutrophil count was measured as indicators of infection status. The levels of inflammatory factors were detected by corresponding kits, cell survival by CCK-8 assay and protein expression level by western blot. RESULTS: S1PR2 was highly expressed in vivo model of lung injury induced by sepsis. It was observed that JTE-013 as antagonist of S1PR2 alleviated the lung tissue injury, endothelial dysfunction and pulmonary edema induced by sepsis. In addition, JTE-013 reduced neutrophil count and levels of inflammatory factors. Moreover, results confirmed that JTE-013 enhanced cell viability and mitigated inflammatory response in cell model of sepsis. CONCLUSIONS: Overall, JTE-013 as an antagonist of S1PR2 could relieve inflammatory injury and endothelial dysfunction induced by sepsis in vivo and vitro, resulting in attenuation of lung injury. These findings elucidated that JTE-013 may be a promising targeted agent for lung injury induced by sepsis.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Sepse/complicações , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/metabolismo , Animais , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Humanos , Masculino , Pirazóis/farmacologia , Piridinas/farmacologia , Ratos Sprague-Dawley , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/metabolismo
3.
Ultrasound Med Biol ; 37(3): 450-64, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21316562

RESUMO

Noninvasive, easy-to-use and accurate measurements of wall shear stress (WSS) in human blood vessels have always been challenging in clinical applications. Echo particle image velocimetry (Echo PIV) has shown promise for clinical measurements of local hemodynamics and wall shear rate. Thus far, however, the method has only been validated under simple flow conditions. In this study, we validated Echo PIV under in vitro and in vivo conditions. For in vitro validation, we used an anatomically correct, compliant carotid bifurcation flow phantom with pulsatile flow conditions, using optical particle image velocimetry (optical PIV) as the reference standard. For in vivo validation, we compared Echo PIV-derived 2-D velocity fields obtained at the carotid bifurcation in five normal subjects against phase-contrast magnetic resonance imaging (PC-MRI)-derived velocity measurements obtained at the same locations. For both studies, time-dependent, 2-D, two-component velocity vectors; peak/centerline velocity, flow rate and wall shear rate (WSR) waveforms at the common carotid artery (CCA), carotid bifurcation and distal internal carotid artery (ICA) were examined. Linear regression, correlation analysis and Bland-Altman analysis were used to quantify the agreement of different waveforms measured by the two techniques. In vitro results showed that Echo PIV produced good images of time-dependent velocity vector maps over the cardiac cycle with excellent temporal (up to 0.7 ms) and spatial (∼0.5 mm) resolutions and quality, comparable with optical PIV results. Further, good agreement was found between Echo PIV and optical PIV results for velocity and WSR measurements. In vivo results also showed good agreement between Echo PIV velocities and phase contrast MRI velocities. We conclude that Echo PIV provides accurate velocity vector and WSR measurements in the carotid bifurcation and has significant potential as a clinical tool for cardiovascular hemodynamics evaluation.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiologia , Imagem de Perfusão do Miocárdio/métodos , Reologia/métodos , Ultrassonografia/métodos , Humanos , Projetos Piloto , Resistência ao Cisalhamento
4.
BMC Syst Biol ; 4: 122, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20809933

RESUMO

BACKGROUND: The cellular responses of bacteria to superoxide stress can be used to model adaptation to severe environmental changes. Superoxide stress promotes the excessive production of reactive oxygen species (ROS) that have detrimental effects on cell metabolic and other physiological activities. To antagonize such effects, the cell needs to regulate a range of metabolic reactions in a coordinated way, so that coherent metabolic responses are generated by the cellular metabolic reaction network as a whole. In the present study, we have used a quantitative metabolic flux analysis approach, together with measurement of gene expression and activity of key enzymes, to investigate changes in central carbon metabolism that occur in Escherichia coli in response to paraquat-induced superoxide stress. The cellular regulatory mechanisms involved in the observed global flux changes are discussed. RESULTS: Flux analysis based on nuclear magnetic resonance (NMR) and mass spectroscopy (MS) measurements and computation provided quantitative results on the metabolic fluxes redistribution of the E. coli central carbon network under paraquat-induced oxidative stress. The metabolic fluxes of the glycolytic pathway were redirected to the pentose phosphate pathway (PP pathway). The production of acetate increased significantly, the fluxes associated with the TCA cycle decreased, and the fluxes in the glyoxylate shunt increased in response to oxidative stress. These global flux changes resulted in an increased ratio of NADPH:NADH and in the accumulation of α-ketoglutarate. CONCLUSIONS: Metabolic flux analysis provided a quantitative and global picture of responses of the E. coli central carbon metabolic network to oxidative stress. Systematic adjustments of cellular physiological state clearly occurred in response to changes in metabolic fluxes induced by oxidative stress. Quantitative flux analysis therefore could reveal the physiological state of the cell at the systems level and is a useful complement to molecular systems approaches, such as proteomics and transcription analyses.


Assuntos
Carbono/metabolismo , Biologia Computacional/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxidos/farmacologia , Escherichia coli/citologia , Escherichia coli/genética , Perfilação da Expressão Gênica , NAD/metabolismo , NADP/metabolismo , Paraquat/farmacologia
5.
J Acoust Soc Am ; 126(4): 1766-75, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19813791

RESUMO

The theoretical understanding of encapsulated microbubble response to high-frequency ultrasound (HFUS) excitation is still limited although some novel experimental HFUS contrast imaging techniques have been well developed. In this paper, the higher-order modal (HOM) contributions to the scattered field are studied for such microbubbles driven by 1-100 MHz ultrasound. An exact solution of all small-amplitude vibrational modes of a single encapsulated microbubble in water is given by the wave scattering theory (WST) method and compared to results obtained from Church's Rayleigh-Plesset-like model for the small-amplitude radial oscillation of a microbubble in an incompressible fluid. From numerical results, we show that the HOM field contribution is significant for scattering properties from individual Nycomed microbubbles with normalized frequency > or = 0.2. It is also shown that the multiple scattering is strengthened for monodispersed Definity microbubbles of 3 microm radius at frequencies >40 MHz. However, comparisons between the authors' analyses and known experimental data for polydispersed Definity microbubbles indicate that the HOM contributions are insignificant in attenuation estimation at frequencies <50 MHz. In conclusion, the WST model analysis suggests that HOM scattering is an important consideration for single bubbles but may be less critical in the modeling of polydispersed Definity bubbles at high frequencies.


Assuntos
Microbolhas , Modelos Teóricos , Ultrassom , Algoritmos , Simulação por Computador
6.
Bioinformatics ; 23(9): 1115-23, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17332023

RESUMO

MOTIVATION: Flux estimation by using (13) C-labeling pattern information of metabolites is currently the only method that can give accurate, detailed quantification of all intracellular fluxes in the central metabolism of a microorganism. In essence, it corresponds to a constrained optimization problem which minimizes a weighted distance between measured and simulated results. Characteristics, such as existence of multiple local minima, non-linear and non-differentiable make this problem a special difficulty. RESULTS: In the present work, we propose an evolutionary-based global optimization algorithm taking advantage of the convex feature of the problem's solution space. Based on the characteristics of convex spaces, specialized initial population and evolutionary operators are designed to solve (13)C-based metabolic flux estimation problem robustly and efficiently. The algorithm was applied to estimate the central metabolic fluxes in Escherichia coli and compared with conventional optimization technique. Experimental results illustrated that our algorithm is capable of achieving fast convergence to good near-optima and maintaining the robust nature of evolutionary algorithms at the same time. AVAILABILITY: Available from the authors upon request.


Assuntos
Algoritmos , Carbono/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Modelos Biológicos , Transdução de Sinais/fisiologia , Simulação por Computador , Metabolismo Energético/fisiologia
7.
Ultrasonics ; 44 Suppl 1: e115-8, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-16854444

RESUMO

In this paper, the multiple scattering of interacting encapsulated microbubbles in suspensions is calculated using two novel approaches--Kargl's effective medium approach and Ye and Ding's approach of 2nd-order correction. Two types of contrast agents with bubbles of different sizes and concentrations are chosen for our numerical simulations. One is Albunex, which is depicted by Church and has a size range of several microns, and the other is sodium laureate solution (before fractionation) described by Soetanto and Chan and has an average size of 35.5 microm. The numerical results from these two approaches are compared with that from the linear approximation. It is found that the multiple scattering effects on attenuation and dispersion of sound in suspensions are evident in the cases of high bubble volume fractions, basically greater than the order of 1 x 10(-4), and much more obvious for larger bubbles with average size of tens of microns.


Assuntos
Meios de Contraste/química , Meios de Contraste/efeitos da radiação , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Modelos Químicos , Ultrassonografia/métodos , Simulação por Computador , Relação Dose-Resposta à Radiação , Tamanho da Partícula , Doses de Radiação , Espalhamento de Radiação
8.
Ultrasound Med Biol ; 32(6): 961-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16785017

RESUMO

The phenomenon of image distortions caused by the multiple scattering (MS) effects of encapsulated microbubbles in ultrasoniqc imaging was experimentally found in previous studies (Soetanto and Chan 2000a), but its mechanism has not been fully understood. To study the MS effects of microbubbles in contrast imaging, two approaches are employed in this article--the effective medium approach initialized by Kargl (2002), which includes all the high-order rescattering of free bubbles, and the classic lowest-order approximation approach of Commander and Prosperetti (1989), which ignores the higher-order rescattering between bubbles. In this work, they are modified to model encapsulated microbubble suspensions, and the discrepancies in attenuation coefficients calculated by these two approaches, i.e., the higher-order rescattering of bubbles are defined as the measure of the MS effects of microbubbles. The intrinsic relations between the MS effects of microbubbles in suspensions and physical properties of the microbubbles, such as the bubble concentrations, sizes, and the shell thicknesses etc., are simulated and discussed. It is found that in suspensions for identical microbubbles >12 microm in size, the MS effects come to be significant when the bubble concentrations exceed 1 x 10(5) bubbles/mL. The MS effects of microbubbles with broad size spectrums are examined by simulating Soetanto and Chan's experiments. Also, the MS effects of UCAs in current ultrasonic imaging practice are discussed. The STARs and extinction cross-sections of different-sized individual encapsulated microbubbles are calculated for further investigations on the mechanism of the MS effects of UCAs.


Assuntos
Meios de Contraste , Microbolhas , Ultrassonografia , Acústica , Humanos , Modelos Teóricos , Tamanho da Partícula
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