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1.
J Magn Reson Imaging ; 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668069

RESUMO

BACKGROUND: Left ventricular global function index (LVGFI) integrates LV volumetric and functional parameters. In patients with end-stage renal disease (ESRD), cardiac injury manifests as LV hypertrophy and dysfunction. However, the prognostic value of LVGFI in this population remains unclear. PURPOSE: To investigate the association of LVGFI with major adverse cardiac events (MACE) in patients with ESRD. STUDY TYPE: Prospective. POPULATION: One hundred fifty-eight ESRD patients (mean age: 54.1 ± 14.4 years; 105 male) on maintenance dialysis. FILED STRENGTH/SEQUENCE: 3.0 T, balanced steady-state free precession (bSSFP) cine and modified Look-Locker inversion recovery (MOLLI) sequences. ASSESSMENT: LV volumetric and functional parameters were determined from bSSFP images. LVGFI was calculated as the ratio of stroke volume to global volume and native T1 was determined from MOLLI T1 maps. MACE was recorded on follow up. Models were developed to predict MACE from conventional risk factors combined with LVGFI, GLS, native T1, and LV mass index (LVMI), respectively. Subgroup analyses were further performed in participants with LVEF above median. STATISTICAL TESTS: Cox proportional hazard regression and log-rank test were used to investigate the association between LVGFI and MACE. The predictive models were evaluated and compared using Harrell's C-statistics and DeLong tests. A P value <0.05 was considered statistically significant. RESULTS: Thirty-four MACE occurred during the median follow-up period of 26 months. The hazard of MACE increased by 114% for each 10% decrease in LVGFI in univariable analysis. The predictive model consisting of LVGFI (C-statistic: 0.724) had significantly better predictive performance than the others (all P < 0.001). These results were consistent in patients (N = 79) with LVEF > median (63.54%). DATA CONCLUSION: LVGFI is a novel marker for MACE risk stratification in patients with ESRD and was better able to predict MACE than native T1 mapping and GLS. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

2.
Quant Imaging Med Surg ; 13(6): 3703-3715, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37284097

RESUMO

Background: Ultrasound has advantages in prostate cancer (PCa) detection and biopsy guidance but lacks a comprehensive quantitative evaluation model with multiparametric features. We aimed to construct a biparametric ultrasound (BU) scoring system for PCa risk assessment and to provide an option for clinically significant prostate cancer (csPCa) detection. Methods: From January 2015 to December 2020, 392 consecutive patients at Chongqing University Cancer Hospital who underwent BU (grayscale, Doppler flow imaging, and contrast-enhanced ultrasound) and multiparametric magnetic resonance imaging (mpMRI) before biopsy were retrospectively enrolled in the training set to construct the scoring system. From January 2021 to May 2022, 166 consecutive patients at Chongqing University Cancer Hospital were retrospectively enrolled in the validation set. The ultrasound system was compared with mpMRI, and the gold standard was a biopsy. The primary outcome was the detection of csPCa in any area with a Gleason score (GS) ≥3+4, and the secondary outcome was defined as a GS ≥4+3 and/or maximum cancer core length (MCCL) ≥6 mm. Results: Malignant association features in the nonenhanced biparametric ultrasound (NEBU) scoring system included echogenicity, capsule, and gland asymmetrical vascularity. In the biparametric ultrasound scoring system (BUS), the feature of contrast agent arrival time was added. In the training set, the area under the curves (AUCs) of the NEBU scoring system, BUS, and mpMRI were 0.86 [95% confidence interval (CI): 0.82-0.90], 0.86 (95% CI: 0.82-0.90), and 0.86 (95% CI: 0.83-0.90), respectively (P>0.05). Similar results were also observed in the validation set, in which the areas under the curves were 0.89 (95% CI: 0.84-0.94), 0.90 (95% CI: 0.85-0.95), and 0.88 (95% CI: 0.82-0.94), respectively (P>0.05). Conclusions: We constructed a BUS that showed efficacy and value for csPCa diagnosis as compared with mpMRI. However, in limited circumstances, the NEBU scoring system may also be an option.

3.
Hum Genet ; 142(6): 835-847, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37095353

RESUMO

Fetal hyperechogenic kidneys (HEK) is etiologically a heterogeneous disorder. The aim of this study was to identify the genetic causes of HEK using prenatal chromosomal microarray analysis (CMA) and exome sequencing (ES). From June 2014 to September 2022, we identified 92 HEK fetuses detected by ultrasound. We reviewed and documented other ultrasound anomalies, microscopic and submicroscopic chromosomal abnormalities, and single gene disorders. We also analyzed the diagnostic yield of CMA and ES and the clinical impact the diagnosis had on pregnancy management. In our cohort, CMA detected 27 pathogenic copy number variations (CNVs) in 25 (25/92, 27.2%) fetuses, with the most common CNV being 17q12 microdeletion syndrome. Among the 26 fetuses who underwent further ES testing, we identified 7 pathogenic/likely pathogenic variants and 8 variants of uncertain significance in 9 genes in 12 fetuses. Four novel variants were first reported herein, expanding the mutational spectra for HEK-related genes. Following counseling, 52 families chose to continue the pregnancy, and in 23 of them, postnatal ultrasound showed no detectable renal abnormalities. Of these 23 cases, 15 had isolated HEK on prenatal ultrasound. Taken together, our study showed a high rate of detectable genetic etiologies in cases with fetal HEK at the levels of chromosomal (aneuploidy), sub-chromosomal (microdeletions/microduplications), and single gene (point mutations). Therefore, we speculate that combined CMA and ES testing for fetal HEK is feasible and has good clinical utility. When no genetic abnormalities are identified, the findings can be transient, especially in the isolated HEK group.


Assuntos
Variações do Número de Cópias de DNA , Diagnóstico Pré-Natal , Gravidez , Feminino , Humanos , Sequenciamento do Exoma , Aberrações Cromossômicas , Feto/diagnóstico por imagem , Feto/anormalidades , Análise em Microsséries , Rim/diagnóstico por imagem
4.
Comput Biol Med ; 152: 106264, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535209

RESUMO

The widespread of SARS-CoV-2 presents a significant threat to human society, as well as public health and economic development. Extensive efforts have been undertaken to battle against the pandemic, whereas effective approaches such as vaccination would be weakened by the continuous mutations, leading to considerable attention being attracted to the mutation prediction. However, most previous studies lack attention to phylogenetics. In this paper, we propose a novel and effective model TEMPO for predicting the mutation of SARS-CoV-2 evolution. Specifically, we design a phylogenetic tree-based sampling method to generate sequence evolution data. Then, a transformer-based model is presented for the site mutation prediction after learning the high-level representation of these sequence data. We conduct experiments to verify the effectiveness of TEMPO, leveraging a large-scale SARS-CoV- 2 dataset. Experimental results show that TEMPO is effective for mutation prediction of SARS- CoV-2 evolution and outperforms several state-of-the-art baseline methods. We further perform mutation prediction experiments of other infectious viruses, to explore the feasibility and robustness of TEMPO, and experimental results verify its superiority. The codes and datasets are freely available at https://github.com/ZJUDataIntelligence/TEMPO.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Filogenia , Mutação , Pandemias
5.
Eur Radiol ; 33(3): 2027-2038, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36260118

RESUMO

OBJECTIVES: To explore the diagnostic potential of texture analysis applied to native T1 maps obtained from cardiac magnetic resonance (CMR) images for the assessment of heart failure with preserved ejection fraction (HFpEF) among patients with end-stage renal disease (ESRD). METHODS: This study, conducted from June 2018 to November 2020, included 119 patients (35 on hemodialysis, 55 on peritoneal dialysis, and 29 with kidney transplants) in Renji Hospital. Native T1 maps were assessed with texture analysis, using a freely available software package, in participants who underwent cardiac MRI at 3.0 T. Four texture features, selected by dimension reduction specific to the diagnosis of HFpEF, were analyzed. Multivariate logistic regression was performed to examine the independent association between the selected features and HFpEF in ESRD patients. RESULTS: Seventy-six of 119 patients were diagnosed with HFpEF. Demographic, laboratory, cardiac MRI, and echocardiogram characteristics were compared between HFpEF and non-HFpEF groups. The four texture features that were analyzed showed statistically significant differences between groups. In multivariate analysis, age, left atrial volume index (LAVI), and sum average 4 (SA4) turned out to be independent predictors for HFpEF in ESRD patients. Combining the texture feature, SA4, with typical predictive factors resulted in higher C-index (0.923 vs. 0.898, p = 0.045) and a sensitivity and specificity of 79.2% and 95.2%, respectively. CONCLUSIONS: Texture analysis of T1 maps adds diagnostic value to typical clinical parameters for the assessment of heart failure with preserved ejection fraction in patients with end-stage renal disease. KEY POINTS: • Non-invasive assessment of HFpEF can help predict prognosis in ESRD patients and help them take timely preventative measures. • Texture analysis of native T1 maps adds diagnostic value to the typical clinical parameters for the assessment of HFpEF in patients with ESRD.


Assuntos
Insuficiência Cardíaca , Falência Renal Crônica , Humanos , Volume Sistólico , Insuficiência Cardíaca/diagnóstico , Coração , Imageamento por Ressonância Magnética , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico por imagem , Função Ventricular Esquerda
6.
Artigo em Inglês | MEDLINE | ID: mdl-36554580

RESUMO

Carbon emissions trading policy has received widespread attention from scholars as a core policy tool to reduce carbon emissions. While most scholars have previously focused on the carbon emission reduction effect, this paper investigates the impact of carbon emissions trading policy on green technology innovation using a differences-in-differences method based on provincial panel data from 2005-2019, using a carbon emissions trading pilot as a quasi-natural experiment. The findings show that the policy can significantly promote green technology innovation, but with a lagged effect, and this finding still holds in the robustness test. Further heterogeneity analysis reveals that the stronger the human capital, the stronger the intellectual property protection and the stronger the marketization with better policy effects. In addition, carbon emissions trading policy can indirectly affect green technology innovation by influencing research investment.


Assuntos
Carbono , Invenções , Humanos , Carbono/análise , Políticas , Investimentos em Saúde , China
7.
J Autoimmun ; 128: 102798, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35182896

RESUMO

To explore bias in lupus erythematosus (LE) randomized clinical trials (RCTs) and to help the development of benchmarks for future trials and management. We searched systematically three databases and three registries to summarize the interventional randomized clinical trials (RCTs) and identify factors associated with participant loss. Trials which examined pharmacological interventions with control group were included and a meta-analysis was carried out by using fixed and random effects models to calculate risk ratio of participant loss in the intervention and control groups. A total of 481 trials with 68,582 participants met our inclusion criteria, organ specific interventional studies along with trials that address quality of life attributes and geopolitical disparities are missing or lagging behind. 90 trials were involved in the meta-analyses, the withdrawal ratio between intervention and control groups was distinctly influenced by national income of the trial-conducted country. In high income countries, the withdrawal ratio was relatively constant, while for trials conducted in low and middle income countries, the results were altered by trial registration, year of start, number of centers, number of participants, and primary outcome identification. Moreover, the comparability of participants was also worrying, trial location and registration status altered basal participant adherence. Our study reveals the unexpectedly huge heterogeneity brought by national income and trial registration in lupus RCTs worldwide. To maintain the fundamental repeatability and referenceability of LE RCTs, rigorously designed single-country trials with diverse inclusion criteria are needed.


Assuntos
Qualidade de Vida , Humanos , Razão de Chances
8.
Econ Lett ; 209: 110099, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34629571

RESUMO

The rapid spread of the novel coronavirus (COVID-19) has had a dramatic effect on financial markets worldwide. This paper explores the association between rare disasters, macroeconomic policy, and the exchange rate, using COVID-19 as an example. Analysis of data from 27 advanced and emerging economies reveals a strong correlation between COVID-19 and time-varying risk premiums in the foreign exchange market. Moreover, the spread of COVID-19 significantly depreciates the domestic exchange rate in emerging markets, but not in advanced countries. During the COVID-19 crisis, expansionary fiscal policies and unconventional monetary policies led to an appreciation of local currencies. However, conventional expansionary monetary policies had the opposite effect, indicating that the traditional effect of monetary policy on the exchange rate takes precedence even in the event of a rare disaster.

9.
J Magn Reson Imaging ; 54(1): 290-300, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33604934

RESUMO

BACKGROUND: Noncontrast cardiac T1 times are increased in dialysis patients which might indicate fibrotic alterations in uremic cardiomyopathy. PURPOSE: To explore the application of the texture analysis (TA) of T1 images in the assessment of myocardial alterations in dialysis patients. STUDY TYPE: Case-control study. POPULATION: A total of 117 subjects, including 22 on hemodialysis, 44 on peritoneal dialysis, and 51 healthy controls. FIELD STRENGTH: A 3 T, steady-state free precession (SSFP) sequence, modified Look-Locker imaging (MOLLI). ASSESSMENT: Two independent, blinded researchers manually delineated endocardial and epicardial borders of the left ventricle (LV) on midventricular T1 maps for TA. STATISTICAL TESTS: Texture feature selection was performed, incorporating reproducibility verification, machine learning, and collinearity analysis. Multivariate linear regressions were performed to examine the independent associations between the selected texture features and left ventricular function in dialysis patients. Texture features' performance in discrimination was evaluated by sensitivity and specificity. Reproducibility was estimated by the intraclass correlation coefficient (ICC). RESULTS: Dialysis patients had greater T1 values than normal (P < 0.05). Five texture features were filtered out through feature selection, and four showed a statistically significant difference between dialysis patients and healthy controls. Among the four features, vertical run-length nonuniformity (VRLN) had the most remarkable difference among the control and dialysis groups (144 ± 40 vs. 257 ± 74, P < 0.05), which overlap was much smaller than Global T1 times (1268 ± 38 vs. 1308 ± 46 msec, P < 0.05). The VRLN values were notably elevated (cutoff = 170) in dialysis patients, with a specificity of 97% and a sensitivity of 88%, compared with T1 times (specificity = 76%, sensitivity = 60%). In dialysis patients, VRLN was significantly and independently associated with left ventricular ejection fraction (P < 0.05), global longitudinal strain (P < 0.05), radial strain (P < 0.05), and circumferential strain (P < 0.05); however, T1 was not. DATA CONCLUSION: The texture features obtained by TA of T1 images and VRLN may be a better parameter for assessing myocardial alterations than T1 times. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.


Assuntos
Cardiomiopatias , Função Ventricular Esquerda , Cardiomiopatias/diagnóstico por imagem , Estudos de Casos e Controles , Humanos , Imageamento por Ressonância Magnética , Imagem Cinética por Ressonância Magnética , Miocárdio , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Volume Sistólico
10.
Carbohydr Polym ; 257: 117573, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33541632

RESUMO

Chondroitin sulfate (ChS) has shown promising results in promoting cell proliferation and antithrombogenic activity. To engineered develop a dual-function vascular scaffold with antithrombosis and endothelialization, ChS was tethered to collagen to accelerate the growth of endothelial cells and prevent platelet activation. First, ChS was used to conjugate with collagen to generate glycosylated products (ChS-COL) via reductive amination. Then, the fabricated ChS-COL conjugates were electrospun into nanofibers and their morphologies and physicochemical characteristics, cell-scaffold responses and platelet behaviors upon ChS-COL nanofibers were comprehensively characterized to evaluate their potential use for small-diameter vascular tissue-engineered scaffolds. The experimental results demonstrated that the ChS modified collagen electrospun nanofibers were stimulatory of endothelial cell behavior, alleviated thrombocyte activation and maintained an antithrombotic effect in vivo in 10-day post-transplantation. The ChS-COL scaffolds encouraged rapid endothelialization, thus probably ensuring the antithrombotic function in long-term implantation, suggesting their promise for small-diameter vascular tissue engineering applications.


Assuntos
Sulfatos de Condroitina/química , Colágeno/química , Nanofibras/química , Engenharia Tecidual/instrumentação , Alicerces Teciduais/química , Animais , Plaquetas/citologia , Artérias Carótidas/patologia , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Teste de Materiais , Microscopia Eletrônica de Varredura , Fenótipo , Ativação Plaquetária , Poliésteres/química , Coelhos , Suínos , Engenharia Tecidual/métodos
11.
Ecotoxicol Environ Saf ; 203: 111012, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32684522

RESUMO

Planting sweet potato (Ipomoea batatas (L.) Lam.) instead of rice in the area contaminated with heavy metals is one of the measures to ensure people's health and agricultural economy. Therefore, it is important to screen the low accumulation cultivars of sweet potato and to find out the concentration rule of cadmium (Cd) and lead (Pb) in edible parts along with the associated health risks to humans. A field experiment was performed with fourteen of three main types (starch, purple, and edible-type) of sweet potato cultivars grown on farmland polluted with Cd and Pb in eastern Hunan Province, China. The Cd and Pb concentrations in the sweet potato tissues as well as the yield were measured. The yield of the shoot and tuberous root of the fourteen sweet potato cultivars ranged from 14.59 to 68.57 and 26.35-50.76 t ha-1 with mean values of 33.09 and 33.46 t ha-1, respectively. Compared with purple and edible-type cultivars, the starch-type cultivar had lower Cd and Pb concentrations in the flesh, but higher in the shoot. The Cd and Pb concentrations in the flesh of cultivars Shangshu 19, Sushu 24, Yushu 98, and Xiangshu 98 were lower than MCL provided in Chinese National Food Safety Standards GB2762-2017. Based on the hazard index (HI), the consumption of sweet potato flesh is lower health risk, while shoots pose a greater health risk to local people and Cd is the main cause of the risk. As a result, sweet potato cultivars Shangshu 19, Sushu 24, Yushu 98 and Xiangshu 98 can be plant in serve Cd and Pb contaminated soils with the advantages of easy cultivation, high yield and economic benefits without stopping agricultural production.


Assuntos
Cádmio/análise , Exposição Dietética/análise , Ipomoea batatas/química , Chumbo/análise , Poluentes do Solo/análise , China , Produtos Agrícolas/química , Produtos Agrícolas/genética , Exposição Dietética/normas , Inocuidade dos Alimentos , Humanos , Ipomoea batatas/genética , Medição de Risco
12.
Int J Endocrinol ; 2019: 3618169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687019

RESUMO

Iodine deficiency during pregnancy can cause iodine deficiency disorders (IDD). However, it is unclear about iodine and thyroid status of Chinese pregnant women and neonates after the implementation of the revised universal salt iodisation (USI) level in 2012. Therefore, the aim of the cross-sectional study was to determine iodine nutrition and thyroid status among pregnant women and their neonates in China after the implementation of USI. Medical records of pregnant women and neonates in Northern Jiangsu People's Hospital between January 2016 and December 2017 were reviewed and included. We included 3060 mother-and-newborn pairs in the study. Mean age of participants was 28.2 ± 4.1 years. TSH, FT3, and FT4 of participants were within normal reference range. The overall mean neonatal TSH, birth weight, and prevalence of low birth weight (LBW) were 4.86 ± 2.06 mIU/L, 3358 ± 455 g, and 3.2%, respectively. The prevalence of neonatal TSH values >5 mIU/L was 29.3%, suggesting iodine deficiency in the region. In conclusion, our results indicated iodine deficiency in the region, according to the neonatal TSH cutoff recommended by WHO/UNICEF/IGD. More efforts are urgently required to improve iodine status of pregnant women in the region in order to prevent a re-emergence of iodine deficiency.

13.
PLoS One ; 14(6): e0216651, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31206535

RESUMO

In recent years, with the rapid development of China's air transport industry and the change in market consumption structure, service quality has become one of the important factors affecting airline revenue. How to formulate a reasonable pricing strategy and maintain competitiveness in the fierce market competition has become an urgent problem for airlines. First, the impact factor of service quality level in the traditional pricing model is introduced and a static price competition model for multi-oligopoly airlines based on service quality is established in this paper. And then, a dynamic pricing model based on service quality of the multi-oligopoly airlines is established. The model incorporates the weight factor of service quality impact, which is used to indicate the weight of the service quality level in the process of airline dynamic pricing. The research results show that the service quality level of airlines has an indispensable influence on its development. Airlines should improve service quality as soon as possible to enhance market competitiveness and achieve sustainable development.


Assuntos
Ar , Custos e Análise de Custo , Meios de Transporte/economia , Modelos Econômicos , Controle de Qualidade
15.
Abdom Radiol (NY) ; 44(5): 1850-1857, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30694370

RESUMO

PURPOSE: The aim of this study was to investigate the effectiveness of contrast-enhanced ultrasound (CEUS) in predicting early nephropathy in cynomolgus macaques with spontaneous type 2 diabetes mellitus (T2DM). METHODS: Six cynomolgus macaques with spontaneous T2DM and six normal cynomolgus macaques (Group 1) were included in this study. The time-intensity curve was used to obtain parameters such as peak values, red blood volume (RBV), red blood flow (RBF), time to peak (TTP), and mean transit time (MTT). Biopsy renal tissue samples were assessed histopathologically. Six cynomolgus macaques with spontaneous T2DM were subgrouped into T2DM without nephropathy group (Group 2) and T2DM with nephropathy group (Group 3) based on histopathological findings. RESULTS: Peak value had the largest area under the curve comparing with RBF, RBV, TTP, MTT. The sensitivity and specificity of peak value with cut-off value of 38.65 dB for the diagnosis of DN were 98.3% and 83%, respectively. Peak value, RBV, and RBF in Group 3 was significantly decreased compared with Group 1 and Group 2 (P = 0.000, x2 = 23.99; P = 0.003, x2 = 9.14; P = 0.02, x2 = 5.14). CONCLUSIONS: The perfusion parameter of peak value in CEUS might be useful in predicting early diabetic nephropathy in spontaneous T2DM cynomolgus macaques.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas/diagnóstico por imagem , Ultrassonografia/métodos , Animais , Biomarcadores/sangue , Biomarcadores/urina , Biópsia com Agulha de Grande Calibre , Meios de Contraste , Processamento de Imagem Assistida por Computador , Macaca fascicularis , Masculino , Fosfolipídeos , Sensibilidade e Especificidade , Hexafluoreto de Enxofre
16.
J Ultrasound Med ; 37(3): 725-736, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28960465

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of Virtual Touch tissue imaging quantification (VTIQ; Siemens Medical Solutions, Mountain View, CA) in combination with the Thyroid Imaging Reporting and Data System (TI-RADS) for assessing thyroid nodules referred for biopsy. METHODS: A total of 197 surgically or cytologically proven thyroid nodules in 187 patients were included. Nodules evaluated by conventional ultrasound (US) and VTIQ examinations were classified into US TI-RADS categories. The shear wave velocity (SWV) on VTIQ was assessed, and the cutoff value was obtained from a receiver operating characteristic curve analysis. Diagnostic performances of conventional US, VTIQ, and their combination were compared. RESULTS: There were 134 benign and 63 malignant nodules. The sensitivity and specificity for the US TI-RADS were 98.4% and 20.1%, respectively. The areas under the receiver operating characteristic curves for the mean, maximum, minimum, and ratio of the SWV were 0.818, 0.805, 0.799, and 0.728. With a cutoff value of 2.90 m/s, the sensitivity and specificity of the mean SWV were 71.4% and 82.8%. By applying this value or less as a standard for downgrading TI-RADS category 4a to category 3 lesions, the specificity significantly rose from 20.1% to 47.0% (P < .001) without a loss of sensitivity. CONCLUSIONS: The additional application of VTIQ can improve the specificity of the TI-RADS for evaluating thyroid nodules without a loss of sensitivity.


Assuntos
Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas de Informação em Radiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Interface Usuário-Computador , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-28009838

RESUMO

Intersections are one of the major locations where safety is a big concern to drivers. Inappropriate driver behaviors in response to frequent changes when approaching intersections often lead to intersection-related crashes or collisions. Thus to better understand driver behaviors at intersections, especially in the dilemma zone, a Hidden Markov Model (HMM) is utilized in this study. With the discrete data processing, the observed dynamic data of vehicles are used for the inference of the Hidden Markov Model. The Baum-Welch (B-W) estimation algorithm is applied to calculate the vehicle state transition probability matrix and the observation probability matrix. When combined with the Forward algorithm, the most likely state of the driver can be obtained. Thus the model can be used to measure the stability and risk of driver behavior. It is found that drivers' behaviors in the dilemma zone are of lower stability and higher risk compared with those in other regions around intersections. In addition to the B-W estimation algorithm, the Viterbi Algorithm is utilized to predict the potential dangers of vehicles. The results can be applied to driving assistance systems to warn drivers to avoid possible accidents.


Assuntos
Condução de Veículo/psicologia , Comportamento , Cadeias de Markov , Acidentes de Trânsito/prevenção & controle , Algoritmos , Humanos , Probabilidade , Medição de Risco , Fatores de Risco , Segurança
18.
Artigo em Inglês | MEDLINE | ID: mdl-26959043

RESUMO

The objectives of the present study were to investigate heavy metal accumulation in 22 vegetable species and to assess the human health risks of vegetable consumption. Six vegetable types were cultivated on farmland contaminated with heavy metals (Pb, Cd, Cu, Zn, and As). The target hazard quotient (THQ) method was used to assess the human health risks posed by heavy metals through vegetable consumption. Clear differences were found in the concentrations of heavy metals in edible parts of the different vegetables. The concentrations of heavy metals decreased in the sequence as leafy vegetables > stalk vegetables/root vegetables/solanaceous vegetables > legume vegetables/melon vegetables. The ability of leafy vegetables to uptake and accumulate heavy metals was the highest, and that of melon vegetables was the lowest. This indicated that the low accumulators (melon vegetables) were suitable for being planted on contaminated soil, while the high accumulators (leafy vegetables) were unsuitable. In Shizhuyuan area, China, the total THQ values of adults and children through consumption of vegetables were 4.12 and 5.41, respectively, suggesting that the residents may be facing health risks due to vegetable consumption, and that children were vulnerable to the adverse effects of heavy metal ingestion.


Assuntos
Poluição Ambiental , Contaminação de Alimentos/análise , Indicadores Básicos de Saúde , Metais Pesados/análise , Poluentes do Solo/efeitos adversos , Poluentes do Solo/análise , Verduras/química , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China , Humanos , Lactente , Pessoa de Meia-Idade , Medição de Risco , Adulto Jovem
19.
Sci Rep ; 5: 9679, 2015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25902910

RESUMO

First discovered in rural areas of middle-eastern China in 2009, severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne zoonosis affecting hundreds of cases reported in China each year. Using the national surveillance data from 2010 to 2013, we conducted this retrospective epidemiological study and risk assessment of SFTS in China. We found that the incidence of SFTS and its epidemic areas are continuing to grow, but the case fatality rate (CFR) has steadily decreased. SFTS most commonly affected elderly farmers who acquired infection between May and July in middle-eastern China. However, other epidemiological characteristics such as incidence, sex ratio, CFR, and seasonality differ substantially across the affected provinces, which seem to be consistent with local agricultural activities and the seasonal abundance of ticks. Spatial scan statistics detected three hot spots of SFTS that accounted for 69.1% of SFTS cases in China. There was a strong association of SFTS incidence with temporal changes in the climate within the clusters. Multivariate modeling identified climate conditions, elevation, forest coverage, cattle density, and the presence of Haemaphysalis longicornis ticks as independent risk factors in the distribution of SFTS, based on which a predicted risk map of the disease was derived.


Assuntos
Trombocitopenia/complicações , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Agricultura , Animais , Área Sob a Curva , Criança , Pré-Escolar , China/epidemiologia , Clima , Análise por Conglomerados , Feminino , Febre/etiologia , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Medição de Risco , Estações do Ano , Índice de Gravidade de Doença , Síndrome , Adulto Jovem , Zoonoses/complicações , Zoonoses/patologia
20.
Environ Toxicol Chem ; 32(12): 2719-27, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24038101

RESUMO

Soybean is one of most important dicotyledonous food crops and is widely planted in Hunan Province, China. However, mining activity causes contamination of the soil in which soybean grows. To assess the impact of mining-induced soil contamination on soybean plants, a geoaccumulation index (I(geo)) was used to evaluate 20 soil samples from the mining and smelting areas of southern Hunan Province. The results indicated that Zn ranged from uncontaminated to a moderately contaminated level (I(geo)<1), Pb was at a strongly contaminated level (I(geo)>3), and Cd was at an extremely contaminated level (I(geo)>5) across the whole study area. All of the studied soybean plants were affected by heavy metal Pb and Cd contamination, and the mean concentrations in seeds were 13.9 mg/kg and 2.95 mg/kg, respectively. The estimated bioconcentration factor and translocation factor showed that the soybean roots had a strong Cd bioconcentration capability and the stems had a strong translocation capability in terms of Pb, Cd, and Zn, with preferential transference of metals to the soybean leaves. The bioavailable fraction in the soil was characterized by the exchangeable fraction of heavy metals. In the present study, the bioavailable fractions of Pb, Cd, and Zn were significantly positively correlated with the concentration of these metals in soybean tissues (roots, stems, leaves, husks, and seeds).


Assuntos
Glycine max/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Animais , China , Concentração de Íons de Hidrogênio , Metalurgia , Metais Pesados/análise , Mineração , Poluentes do Solo/química , Glycine max/química
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