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1.
J Appl Gerontol ; : 7334648241236237, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553848

RESUMO

Home- and community-based services (HCBS) are optimal ways to deal with disability problems among older adults. This study aims to analyze urban-rural disparities in the relationship between HCBS utilization and levels of disability among Chinese older adults with disabilities, so as to meet the long-term care needs of them. In applying the Andersen Behavioral Model, bivariate analysis and multivariate regression models were employed using data from 843 older adults with disabilities from the 2018 China Longitudinal Aging Social Survey (CLASS). After adjusting covariates, disability levels among Chinese older adults with disabilities were significantly correlated with HCBS utilization in urban areas but not in rural areas. The urban-rural disparities may be due to the low utilization of HCBS in rural areas (only 11.2%) among older adults with disabilities compared with their urban counterparts (22.7%).

2.
Front Pharmacol ; 14: 1298341, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38044948

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARG), a key transcription factor involved in lipid metabolism and glucose homeostasis, has been implicated in various types of cancer. However, its precise role in cancer remains unclear. In this study, we conducted a comprehensive pan-cancer analysis of PPARG expression using various types of cancer obtained from public databases. We observed significant heterogeneity in PPARG expression across different types of cancer. The association between PPARG expression and patient prognosis was investigated using Cox proportional hazards regression models and survival analysis. Clinical features and protein expression levels in the cohort showed that PPARG expression was strongly associated, suggesting its potential as a therapeutic target. We also evaluated the prognostic potential of PPARG by analyzing immune infiltration and genomic stability. We experimentally validated the potential of PPARG as a therapeutic target by analyzing drug sensitivity profiles, molecular docking simulations, and in vitro cell proliferation assays associated with PPARG expression. We identified common expression patterns of PPARG with other genes involved in key carcinogenic pathways. This provides deeper insights into the molecular mechanisms underlying its carcinogenic role. Additionally, functional enrichment analysis revealed significant enrichment of genes related to drug metabolism, cell proliferation, and immune response pathways associated with PPARG. Our findings highlight the importance of PPARG in the broader biology of cancer and suggest its potential as a diagnostic and therapeutic target for specific types of cancer. The results of our study provide strong support for the potential role of PPARG as a promising prognostic biomarker and immunotherapeutic target across various types of cancer.

3.
Org Lett ; 25(47): 8463-8468, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982592

RESUMO

An intermolecular redox-economical coupling reaction of allyl alcohols with alkynes, catalyzed by Ni-Brønsted acid cocatalysis, has been developed. This method allows for the synthesis of a diverse range of γ,δ-unsaturated ketones with yields ranging from 40% to 94%, while maintaining excellent compatibility with various functional groups. The transformation of the resulting product demonstrates the significant practical value of this method. Further mechanistic investigations have revealed that the reaction proceeds through the formation of an oxa-nickelacycle intermediate.

4.
Chem Sci ; 14(21): 5608-5618, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37265723

RESUMO

Carboacyloxylation of internal alkynes is emerging as a powerful and straightforward strategy for enol ester synthesis. However, the reported examples come with limitations, including the utilization of noble metal catalysts, the control of regio- and Z/E selectivity, and an application in the synthesis of enol carbonates. Herein, a boron Lewis acid-catalyzed intermolecular carboacyloxylation of ynamides with esters to access fully substituted acyclic enol esters in high yield with generally high Z/E selectivity (up to >96 : 4) is reported. Most importantly, readily available allylic carbonates are also compatible with this difunctionalization reaction, representing an atom-economic, catalytic and stereoselective protocol for the construction of acyclic ß,ß-disubstituted enol carbonates of amides for the first time. The application of the carboacyloxylation products to decarboxylative allylations provided a ready access to enantioenriched α-quaternary amides. Moreover, experimental studies and theoretical calculations were performed to illustrate the reaction mechanism and rationalize the stereochemistry.

5.
Eur Radiol ; 33(4): 2768-2778, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36449061

RESUMO

OBJECTIVES: To investigate the ability of CT and endoscopic sonography (EUS) in predicting the malignant risk of 1-2-cm gastric gastrointestinal stromal tumors (gGISTs) and to clarify whether radiomics could be applied for risk stratification. METHODS: A total of 151 pathologically confirmed 1-2-cm gGISTs from seven institutions were identified by contrast-enhanced CT scans between January 2010 and March 2021. A detailed description of EUS morphological features was available for 73 gGISTs. The association between EUS or CT high-risk features and pathological malignant potential was evaluated. gGISTs were randomly divided into three groups to build the radiomics model, including 74 in the training cohort, 37 in validation cohort, and 40 in testing cohort. The ROIs covering the whole tumor volume were delineated on the CT images of the portal venous phase. The Pearson test and least absolute shrinkage and selection operator (LASSO) algorithm were used for feature selection, and the ROC curves were used to evaluate the model performance. RESULTS: The presence of EUS- and CT-based morphological high-risk features, including calcification, necrosis, intratumoral heterogeneity, irregular border, or surface ulceration, did not differ between very-low and intermediate risk 1-2-cm gGISTs (p > 0.05). The radiomics model consisting of five radiomics features showed favorable performance in discrimination of malignant 1-2-cm gGISTs, with the AUC of the training, validation, and testing cohort as 0.866, 0.812, and 0.766, respectively. CONCLUSIONS: Instead of CT- and EUS-based morphological high-risk features, the CT radiomics model could potentially be applied for preoperative risk stratification of 1-2-cm gGISTs. KEY POINTS: • The presence of EUS- and CT-based morphological high-risk factors, including calcification, necrosis, intratumoral heterogeneity, irregular border, or surface ulceration, did not correlate with the pathological malignant potential of 1-2-cm gGISTs. • The CT radiomics model could potentially be applied for preoperative risk stratification of 1-2-cm gGISTs.


Assuntos
Tumores do Estroma Gastrointestinal , Neoplasias Gástricas , Humanos , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/patologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/métodos
6.
BMC Public Health ; 22(1): 1958, 2022 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280809

RESUMO

BACKGROUND: The first three years of life are the critical and sensitive periods for the formation of individual abilities. However, existing data indicates that early childhood development (ECD) in economically vulnerable areas of China is lagging, which is closely related to the lack of parenting knowledge and poor parenting practices. METHODS: We conducted a non-masked cluster-randomized controlled trial in a former nationally designated poverty county of China. All 6-36-month-old children and their caregivers living in 18 communities/clusters (10 towns and 8 districts of the county seat) were enrolled in a 9-month parenting training program. In the treatment-group communities, ECD centers were installed where community workers provided parenting training sessions. If caregivers were unable to visit the center, home-based parenting training was offered. No intervention was provided to the control group. Furthermore, we assigned half of the treatment group to receive monthly developmental feedback in addition to the parenting training. Based on the baseline and follow-up data, we investigated the treatment effects on parenting knowledge, attitudes, and practices through Intention-to-Treat (ITT) and Treatment-on-the-Treated (TOT) analyses. RESULTS: We found no effects on the parenting knowledge and attitudes of the caregivers but significant effects on the parenting practices. The effects were heterogeneous among families with different characteristics. Specifically, on average, the program had the largest effect on internally oriented caregivers, mothers with higher education, and mothers who are primary caregivers. We want to emphasize that, although the ITT effect on parenting practices (the average treatment effect) were stronger for mothers with higher education, the TOT effect on parenting practices (the local average treatment effect, LATE) were stronger for mothers with less education. That is, even though on average the program helped mothers with higher education, but among complier families, the program benefited mothers with less education. CONCLUSION: The findings indicate that, at least in the short run, the program can directly change caregivers' parenting practices without changing their knowledge and attitudes. Future studies are needed to investigate whether parenting knowledge and attitudes can change in the long run.


Assuntos
Cuidadores , Poder Familiar , Criança , Feminino , Pré-Escolar , Humanos , Lactente , Conhecimentos, Atitudes e Prática em Saúde , Desenvolvimento Infantil , Mães/educação , China
7.
Artigo em Inglês | MEDLINE | ID: mdl-35954894

RESUMO

Energy consumption and industrial activities are the primary sources of carbon emissions. As the "world's factory" and the largest carbon emitter, China has been emphasizing the core role of technological innovation in promoting industrial structure upgrades (ISU) and energy efficiency (EE) to reduce carbon emissions from industrial production and energy consumption. This study investigated the mechanism (through ISU and EE) and spillover effect of technological innovation on carbon emission reduction using the panel dataset of 30 Chinese provinces from 2008 to 2019 and spatial econometrics models. The study concluded that (1) technological innovation had a negative direct effect on provincial carbon emissions, while it also showed a spatial spillover effect on neighboring provinces; (2) technological innovation had an indirect effect on provincial carbon emissions reduction through the mediation of energy efficiency improvement, while the mediation effect of industrial structure upgrading is not yet significant; and (3) the effect of technological innovation on carbon emission reduction showed heterogeneity in the eastern, central, and western regions of China. This study provided empirical and theoretical references to decision-makers in China and other developing countries in promoting technological and carbon control policies. More specifically, direct technology investment and indirect investment in industrial structure upgrades and energy efficiency could help with regional carbon emissions reduction.


Assuntos
Dióxido de Carbono , Tecnologia , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Indústrias , Invenções , Investimentos em Saúde
8.
Eur Radiol ; 31(8): 5659-5668, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33616764

RESUMO

OBJECTIVES: To evaluate the performance of a fractional order calculus (FROC) diffusion model for imaging-based assessment of Lauren classification in gastric adenocarcinoma. METHODS: In this study, 43 patients (15 females, 28 males) with gastric adenocarcinoma underwent MRI at 1.5 T. According to pathology-based Lauren classification, 10 patients had diffuse-type, 20 had intestinal-type, and 13 had mixed-type lesions. The diffuse and mixed types were combined as diffuse-and-mixed type to be differentiated from the intestinal type using diffusion MRI. Diffusion-weighted images were acquired by using eleven b-values (0-2000 s/mm2). Three FROC model parameters comprising diffusion coefficient D, intravoxel diffusion heterogeneity ß, and a microstructural quantity µ, together with a conventional apparent diffusion coefficient (ADC), were estimated. The mean parameter values in the tumour were computed by using a percentile histogram analysis. Individual or linear combinations of the mean parameters in the tumour were used to differentiate the diffuse-and-mixed type from the intestinal type using descriptive statistics and receiver operating characteristic (ROC) analyses. RESULTS: Significant differences were observed between diffuse-and-mixed-type and intestinal-type lesions in D (0.99 ± 0.20 µm2/ms vs. 1.11 ± 0.23 µm2/ms; p = 0.036), ß (0.37 ± 0.08 vs. 0.43 ± 0.11; p = 0.043), µ (7.92 ± 2.79 µm vs. 9.87 ± 1.52 µm; p = 0.038), and ADC (0.81 ± 0.34 µm2/ms vs. 0.96 ± 0.19 µm2/ms; p = 0.033). Among the individual parameters, µ produced the largest area under the ROC curve (0.739). The combinations of (D, ß, µ) and (ß and µ) produced the best overall performance with a sensitivity of 0.739, specificity of 0.750, accuracy of 0.744, and area under the curve of 0.793 (95% confidence interval: 0.657-0.929). CONCLUSION: Diffusion MRI with the FROC model holds promise for non-invasive assessment of Lauren classification for gastric adenocarcinoma. KEY POINTS: • High b-value diffusion MRI with a FROC model that is sensitive to tissue microstructures can differentiate the diffuse-and-mixed type from intestinal type of gastric adenocarcinoma. • The combination of FROC parameters produced the best result for distinguishing the diffuse-and-mixed type from the intestinal type with an area under the receiver operating characteristic curve of 0.793. • The FROC model parameters, individually or conjointly, hold promise for repeated, non-invasive evaluations of gastric adenocarcinoma at various time points throughout disease progression or regression to complement conventional Lauren classification.


Assuntos
Adenocarcinoma , Cálculos , Neoplasias Gástricas , Adenocarcinoma/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Masculino , Curva ROC , Neoplasias Gástricas/diagnóstico por imagem
9.
J Environ Sci (China) ; 94: 119-127, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563475

RESUMO

Currently, the wastewater treatment plants (WWTPs) attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge. However, they have not been able to satisfy the increasing ecological safety needs. In this study, the removal of micropollutants was investigated, and the ecological safety was assessed for a local WWTP. Although the total concentration of 31 micropollutants detected was reduced by 83% using the traditional biological treatment processes, the results did not reflect chemicals that had poor removal efficiencies and low concentrations. Of the five categories of micropollutants, herbicides, insecticides, and bactericides were difficult to remove, pharmaceuticals and UV filters were effectively eliminated. The specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5% of aquatic organisms are affected. The photosynthesis inhibition effect from wastewater in the WWTP was negligible, even the untreated raw wastewater. However, the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect, posed potential ecological risk. To decrease non-specific biological effects, especially of macromolecular dissolved organic matter, overall pollutant reduction strategy is necessary. Meanwhile, the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent; ≥ 0.34 g O3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.


Assuntos
Ozônio , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos , Águas Residuárias/análise
10.
Fam Community Health ; 41(4): 233-243, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30134338

RESUMO

The overall goal of this study is to examine whether infant feeding practices differ between mothers and grandmothers in rural China. We randomly sampled 1383 caregivers of infants aged 18 to 30 months living in 351 villages across 174 townships in nationally designated poverty counties in rural areas. Results show that a high fraction of caregivers of 18- to 30-month-old children living in low-income areas of rural China do not regularly engage in positive infant feeding practices. Only 30% of children in our sample achieved adequate dietary diversity. Only 49% of children in our sample were fed meat in the day prior to survey administration. Few caregivers reported giving any vitamin supplements (such as calcium or iron supplements) to their children. We find that 33% of the children were cared for by grandmothers rather than mothers, and that grandmothers feed a less diversified diet to children than do mothers. Most (84%) caregivers rely solely on their own experiences, friends, and family members in shaping their feeding behaviors. Overall infant feeding practices are poor in rural China. Grandmothers engage in poorer feeding practices than do mothers. Grandmothers have improved their feeding practices compared to when their own children were young. Our results suggest shortcomings in the quality of infant feeding practices, at least in part due to an absence of reliable information sources.


Assuntos
Comportamento Alimentar/psicologia , População Rural/tendências , Cuidadores , Pré-Escolar , China , Feminino , Avós , Humanos , Lactente , Recém-Nascido , Masculino , Mães , Fatores Socioeconômicos
11.
Sci Rep ; 6: 33832, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27652518

RESUMO

To compare the capabilities of three-dimensional contrast enhanced ultrasound (3D-CEUS) and dynamic contrast-enhanced magnetic resonance (DCE-MRI) in predicting the response to neoadjuvant chemotherapy (NAC) among breast cancer patients, 48 patients with unilateral breast cancer were recruited for 3D-CEUS and DCE-MRI examinations both before and after NAC; pathology was used to validate the results. This study was approved by the institutional review board, and written informed consent was obtained from each patient. Imaging feature changes and pathological vascularity response, including microvessel density (MVD) and vascular endothelial growth factor (VEGF), were calculated. Pathological complete response (pCR) and major histological response (MHR) were used as references. The 3D-CEUS score, DCE-MRI score, MVD and VEGF significantly decreased (P < 0.0001) after NAC. The correlations between Δ3D-CEUS and ΔDCE-MRI with pCR (r = 0.649, P < 0.0001; r = 0.639, P < 0.0001) and MHR (r = 0.863, P < 0.0001; r = 0.836, P < 0.0001) were significant. All scores showed significant differences between the pCR and non-pCR groups with folder changes of 0.1, 0.1, 2.4, and 2.3, respectively (P = 0.0001, <0.0001, <0.0001 and <0.0001). In conclusion, 3D-CEUS is effective in assessing the response of breast cancer patients undergoing NAC.

12.
Bioresour Technol ; 176: 121-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25460992

RESUMO

To solve the problem of extraction wastewater in citric acid industrial production, an improved integrated citric acid-methane production process was established in this study. Extraction wastewater was treated by anaerobic digestion and then the anaerobic digestion effluent (ADE) was stripped by air to remove ammonia. Followed by solid-liquid separation to remove metal ion precipitation, the supernatant was recycled for the next batch of citric acid fermentation, thus eliminating wastewater discharge and reducing water consumption. 130U/g glucoamylase was added to medium after inoculation and the recycling process performed for 10 batches. Fermentation time decreased by 20% in recycling and the average citric acid production (2nd-10th) was 145.9±3.4g/L, only 2.5% lower than that with tap water (149.6g/L). The average methane production was 292.3±25.1mL/g CODremoved and stable in operation. Excessive Na(+) concentration in ADE was confirmed to be the major challenge for the proposed process.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Ácido Cítrico/metabolismo , Metano/biossíntese , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Amônia/isolamento & purificação , Análise da Demanda Biológica de Oxigênio , Fermentação , Glucana 1,4-alfa-Glucosidase/química , Manihot/química , Metais/isolamento & purificação
13.
J Ultrasound Med ; 33(5): 835-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24764339

RESUMO

OBJECTIVES: The purpose of this study was to differentiate perfusion and vascular characteristics between benign and malignant breast lesions by 3-dimensional contrast-enhanced sonography and evaluate their correlation with microvessel density and vascular endothelial growth factor (VEGF) expression for further clinical exploration. METHODS: Three-dimensional contrast-enhanced sonography was performed in 183 patients with breast lesions, and sonographic characteristics were carefully observed for further analysis. The mean microvessel density and VEGF expression were measured by immunohistochemical analysis. RESULTS: Pathologic results showed 35 benign and 148 malignant cases. Malignancy and benignity differed significantly in peripheral vessel characteristics (number, distribution, course, degree of dilatation, and penetrating vessels), rim perfusion and coarseness degree, intratumoral perfusion type, and intratumoral vessel dilatation (P< .05) but not the presence of peripheral and intratumoral vessels and intratumoral perfusion (P > .05). The specificity of penetrating vessels was 88.6% for diagnosing malignancy. The sensitivity, specificity, and accuracy of rim perfusion coarseness were 90.2%, 70.4%, and 85.3% respectively. The sensitivity of the intratumoral perfusion type was 77.8%, whereas the specificity of intratumoral vessel dilatation was 88.9%. Microvessel density and VEGF expression were significantly correlated with perfusion and vascular characteristics (P < .05), except the presence of peripheral vessels, rim perfusion, and intratumoral perfusion (P> .05). The presence of intratumoral vessels was related to VEGF (P< .05) but not microvessel density (P > .05). CONCLUSIONS: Three-dimensional contrast-enhanced sonographic characteristics were statistically different between benign and malignant breast lesions. Some of them also correlated significantly with microvessel density and VEGF expression and therefore have potential for objective evaluation of tumor angiogenesis.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Imageamento Tridimensional/métodos , Microvasos/patologia , Neovascularização Patológica/diagnóstico , Ultrassonografia Mamária/métodos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/irrigação sanguínea , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Neovascularização Patológica/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
14.
Bioresour Technol ; 148: 453-60, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24077154

RESUMO

An integrated corn ethanol-methane fermentation system was proposed to solve the problem of stillage handling, where thin stillage was treated by anaerobic digestion and then reused to make mash for the following ethanol fermentation. This system was evaluated at laboratory and pilot scale. Anaerobic digestion of thin stillage ran steadily with total chemical oxygen demand removal efficiency of 98% at laboratory scale and 97% at pilot scale. Ethanol production was not influenced by recycling anaerobic digestion effluent at laboratory and pilot scale. Compared with dried distillers' grains with solubles produced in conventional process, dried distillers' grains in the proposed system exhibited higher quality because of increased protein concentration and decreased salts concentration. Energetic assessment indicated that application of this novel process enhanced the net energy balance ratio from 1.26 (conventional process) to 1.76. In conclusion, the proposed system possessed technical advantage over the conventional process for corn fuel ethanol production.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Etanol/síntese química , Sementes/química , Zea mays/química , Aminoácidos/análise , Anaerobiose , Ração Animal , Biomassa , Carboidratos/análise , Fermentação , Laboratórios , Projetos Piloto , Termodinâmica
15.
Bioresour Technol ; 144: 452-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23890978

RESUMO

A lab-scale membrane diffusion packed-bed bioreactor was used to investigate hydrogenotrophic denitrification for tertiary nitrogen removal from municipal wastewater. After start-up, the bioreactor had been operated for 165 days by stepwise increasing influent loading rates at 30 and 15°C. The results indicated that this bioreactor could achieve relatively high nitrogen removal efficiencies. The denitrification rates reached 0.250 and 0.230 kg N/(m(3)d) at 30 and 15°C respectively. The total nitrogen concentration in effluent was entirely below 2.0 mg/L at the steady operation state. The average increase of total organic carbon in effluent was approximately 0.41 mg/L, suggesting the risk of organic residue can be completely controlled. Dissolved oxygen (DO) did not show obviously negative effects on hydrogenotrophic denitrification. There was only slight decrease of DO concentration in effluent, which demonstrated almost all of the hydrogen was used for nitrate reduction.


Assuntos
Reatores Biológicos , Desnitrificação , Hidrogênio/metabolismo , Nitrogênio/isolamento & purificação , Águas Residuárias/química , Purificação da Água/instrumentação , Purificação da Água/métodos , Biodegradação Ambiental , Biofilmes , Reatores Biológicos/microbiologia , Carbono/análise , Cidades , Custos e Análise de Custo , Difusão , Elétrons , Concentração de Íons de Hidrogênio , Membranas Artificiais , Microscopia Eletrônica de Varredura , Nitratos/análise , Compostos Orgânicos/análise , Oxigênio/análise , Temperatura , Eliminação de Resíduos Líquidos , Purificação da Água/economia
16.
PLoS One ; 8(1): e53580, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23326461

RESUMO

BACKGROUND: With the properties of three-column fixation and anterior-approach-only procedure, anterior transpedicular screw (ATPS) is ideal for severe multilevel traumatic cervical instabilities. However, the accurate insertion of ATPS remains challenging. Here we constructed a patient-specific biocompatible drill template and evaluated its accuracy in assisting ATPS insertion. METHODS: After ethical approval, 24 formalin-preserved cervical vertebrae (C2-C7) were CT scanned. 3D reconstruction models of cervical vertebra were obtained with 2-mm-diameter virtual pin tracts at the central pedicles. The 3D models were used for rapid prototyping (RP) printing. A 2-mm-diameter Kirschner wire was then inserted into the pin tract of the RP model before polymethylmethacrylate was used to construct the patient-specific biocompatible drill template. After removal of the anterior soft tissue, a 2-mm-diameter Kirschner wire was inserted into the cervical pedicle with the assistance of drill template. Cadaveric cervical spines with pin tracts were subsequently scanned using the same CT scanner. A 3D reconstruction was performed of the scanned spines to get 3D models of the vertebrae containing the actual pin tracts. The deviations were calculated between 3D models with virtual and actual pin tracts at the middle point of the cervical pedicle. 3D models of 3.5 mm-diameter screws were used in simulated insertion to grade the screw positions. FINDINGS: The patient-specific biocompatible drill template was constructed to assist ATPS insertion successfully. There were no significant differences between medial/lateral deviations (P = 0.797) or between superior/inferior deviations (P = 0.741). The absolute deviation values were 0.82±0.75 mm and 1.10±0.96 mm in axial and sagittal planes, respectively. In the simulated insertion, the screws in non-critical position were 44/48 (91.7%). CONCLUSIONS: The patient-specific drill template is biocompatible, easy-to-apply and accurate in assisting ATPS insertion. Its clinical applications should be further researched.


Assuntos
Materiais Biocompatíveis/farmacologia , Parafusos Ósseos , Vértebras Cervicais/efeitos dos fármacos , Teste de Materiais/métodos , Procedimentos Ortopédicos/métodos , Idoso , Feminino , Humanos , Imageamento Tridimensional , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos
17.
Environ Monit Assess ; 185(7): 6049-62, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23208758

RESUMO

Heavy metals concentrations in surface sediments from Miyun Reservoir were determined to evaluate the pollution and identify the sources. The average content of metals in sediments from Miyun Reservoir followed the order Al>Fe>Ti>Mn>V>Zn>Cr>Ni>Cu>Pb>As>Cd>Hg, and the most mean values were lower than the globe average shale. Heavy metals concentrations at the inflow area of Baihe were higher than those at the inflow area of Chaohe. Heavy metals pollution assessment was carried out by factor enrichment (EF), geoaccumulation index (I(geo)), and potential ecological risk (RI). The EF values for all heavy metals except Hg, Cd, and Cr at several sites were lower than 3, suggesting low anthropogenic impact on the metals level. The I(geo) values of Pb indicated that half of the sites were unpolluted to moderately polluted and mainly located in the Baihe area of the reservoir. The RI showed that heavy metals of Miyun Reservoir were low potential risk, however, Hg approached or belonged to moderate ecological risk at sites of M5, M7, and M13. Correlation analysis and principal component suggested that Ni, Cu, V, Zn, Mn, Cr, Ti, and Pb were derived from soil erosion in upper reaches of the reservoir, while Fe, Cd, Hg, As, and partial Pb originated from anthropogenic sources, particularly industrial mining and gold tailings.


Assuntos
Monitoramento Ambiental , Água Doce/química , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Mineração , Abastecimento de Água/estatística & dados numéricos
18.
Chin J Cancer Res ; 25(6): 722-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24385700

RESUMO

OBJECTIVE: This study investigated the capability of dual-energy spectral computed tomography (CT) to quantitatively evaluate lung perfusion defects that are induced by central lung cancer. METHODS: Thirty-two patients with central lung cancer underwent CT angiography using spectral imaging. A univariate general linear model was conducted to analyze the variance of iodine concentration/CT value with three factors of lung fields. A paired t-test was used to compare iodine concentrations and CT values between the distal end of lung cancer and the corresponding area in the contralateral normal lung. RESULTS: Iodine concentrations increased progressively in the far, intermediate and near ground sides in the normal lung fields at 0.60±0.28, 0.93±0.27 and 1.25±0.38 mg/mL, respectively (P<0.001). The same trend was observed for the CT values [-(840.64±49.08), -(812.66±50.85) and -(760.83±89.17) HU, P<0.001]. The iodine concentration (0.70±0.42 mg/mL) of the lung field in the distal end of lung cancer was significantly lower than the corresponding area in the contralateral normal lung (1.19±0.62 mg/mL) (t=-7.23, P<0.001). However, the CT value of lung field in the distal end of lung cancer was significantly higher than the corresponding area in the contralateral normal lung [-(765.29±93.34) HU vs. -(800.07±76.18) HU, t=3.564, P=0.001]. CONCLUSIONS: Spectral CT imaging based on the spectral differentiation of iodine is feasible and can quantitatively evaluate pulmonary perfusion and identify perfusion defects that are induced by central lung cancer. Spectral CT seems to be a promising technique for the simultaneous evaluation of both morphological and functional lung information.

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