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BACKGROUND: The use of peritumoral features to determine the survival time of patients with rectal cancer (RC) is still imprecise. PURPOSE: To explore the correlation between intratumoral, peritumoral and combined features, and overall survival (OS). STUDY TYPE: Retrospective. POPULATION: One hundred sixty-six RC patients (53 women, 113 men; average age: 55 ± 12 years) who underwent radical resection after neoadjuvant therapy. FIELD STRENGTH/SEQUENCE: 3 T; T2WI sagittal, T1WI axial, T2WI axial with fat suppression, and high-resolution T2WI axial sequences, enhanced T1WI axial and sagittal sequences with fat suppression. ASSESSMENT: Radiologist A segmented 166 patients, and radiologist B randomly segmented 30 patients. Intratumoral and peritumoral features were extracted, and features with good stability (ICC ≥0.75) were retained through intra-observer analysis. Seven classifiers, including Logistic Regression (LR), Support Vector Machine (SVM), K-Nearest Neighbors (KNN), Random Forest (RF), Extremely randomized trees (ET), eXtreme Gradient Boosting (XGBoost), and LightGBM (LGBM), were applied to select the classifier with the best performance. Next, the Rad-score of best classifier and the clinical features were selected to establish the models, thus, nomogram was built to identify the association with 1-, 3-, and 5-year OS. STATISTICAL TESTS: LASSO, regression analysis, ROC, DeLong method, Kaplan-Meier curve. P < 0.05 indicated a significant difference. RESULTS: Only Node (irregular tumor nodules in the surrounding mesentery) and ExtraMRF (lymph nodes outside the perirectal mesentery) were significantly different in 20 clinical features. Twelve intratumoral, 3 peritumoral, and 14 combined features related to OS were selected. LR, SVM, and RF classier showed the best efficacy in the intratumoral, peritumoral, and combined model, respectively. The combined model (AUC = 0.954 and 0.821) had better survival association than the intratumoral model (AUC = 0.833 and 0.813) and the peritumoral model (AUC = 0.824 and 0.687). DATA CONCLUSION: The proposed peritumoral model with radiomics features may serve as a tool to improve estimated survival time. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 4.
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OBJECTIVE: The aim of this study is to investigate the radiation dose and image quality of head CT using SPS and OBTCM techniques. METHODS: Three anthropomorphic head phantoms (1-yr-old, 5-yr-old, and adult) were used. Images were acquired using four modes (Default protocol, OBTCM, SPS, and SPS+OBTCM). Absorbed dose to the lens, anterior brain (brain_A), and posterior brain (brain_P) was measured and compared. Image noise and CNR were assessed in the selected regions of interest (ROIs). RESULTS: Compared with that in the Default protocol, the absorbed dose to the lens reduced by up to 28.33%,71.38%, and 71.12% in OBTCM, SPS, and SPS+OBTCM, respectively. The noise level in OBTCM slightly (≤1.45HU) increased than that in Default protocol, and the SPS or SPS+OBTCM mode resulted in a quantitatively small increase (≤2.58HU) in three phantoms. There was no significant difference in CNR of different phantoms under varies scanning modes (pâ>â0.05). CONCLUSIONS: During head CT examinations, the SPS mode can reduce the radiation dose while maintaining image quality. SPS+OBTCM couldn't further effectively reduce the absorbed dose to the lens for 1-yr and 5-yr-old phantoms. Thus, SPS mode in pediatric and SPS+OBTCM mode in adult are better than other modes, and should be used in clinical practice.
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Redução da Medicação , Proteção Radiológica , Adulto , Humanos , Criança , Doses de Radiação , Proteção Radiológica/métodos , Cabeça/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imagens de FantasmasRESUMO
BACKGROUND: The reproducibility of intravoxel incoherent motion (IVIM)-based radiomics studies in humans has not been reported. PURPOSE: To determine the inter- and intra-observer variability on the reproducibility of IVIM-based radiomics features in cervical cancer (CC). MATERIAL AND METHODS: The IVIM images of 25 patients with CC were retrospectively collected. Based on the high-resolution T2-weighted images, the regions of interest (ROIs) were independently delineated twice in diffusion-weighted images at a b value of 1000 s/mm2 (interval time was one month) by two radiologists. This was done at the largest transversal cross-sections of the tumors. The ROI was subsequently used in apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) maps derived from IVIM images. In total, 105 radiomics features were then finally extracted from the IVIM-derived maps. The inter- and intra-observer reproducibility of IVIM-derived features was then evaluated using the intraclass correlation coefficient. RESULTS: Inter- and intra-observer variability affected the reproducibility of radiomics features. D* map had 100% and 95% reproducible features, ADC map had 89% and 93%, D map had 97% and 86%, while f map had 54% and 62% reproducible features with good to excellent reliability in the intra-observer analysis. Similarly, D* map had 90% and 94%, ADC map had 85% and 70%, D map had 81% and 78%, while f map had 41% and 93% reproducible features with good to excellent reliability in the inter-observer analysis. CONCLUSION: Inter- and intra-observer variability can affect radiomics analysis. Cognizant to this, multicenter studies should pay more attention to intra- and inter-observer variability.
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Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
BACKGROUND: Cerebral structures in both cortical and subcortical regions change with aging. More specific and comprehensive studies are needed to better elucidate these changes. PURPOSE: To investigate the relationships between age and cerebral structures regarding cortical and subcortical changes. STUDY TYPE: Cross-cohort research. POPULATION: 54 healthy adults (28 females) aged 21-71 years. FIELD STRENGTH/SEQUENCE: T1 -weighted imaging was performed at 1.5T. ASSESSMENT: The cortical thickness, local gyrification index (LGI), and the volumes of total gray matter (GM), white matter (WM), white matter hyperintensity (WMH), deep gray matter nuclei (putamen, pallidum, thalamus, caudate, amygdala, accumbens area, and hippocampus), ventricles, and hippocampal subfields were obtained using FreeSurfer software. STATISTICAL TESTS: Regression analysis was performed to determine the relationships between age and cortical thickness, LGI, and volumes of subcortical structures. Uncorrected P values ≤ 0.001 and R2 > 0.16 were considered significant. RESULTS: The cortical thickness and LGI decreased with age throughout almost all brain regions (R2 > 0.16; P ≤ 0.001). Except for the volumes of the WM and 4th ventricle (R2 < 0.16; P > 0.001), the volumes of the GM, WMH, lateral ventricle, inferior lateral ventricle, and 3rd ventricle showed a nonlinear correlation with aging (R2 > 0.16; P ≤ 0.001). For deep gray matter nuclei, the thalamus volume was significantly decreased with aging (R2 = 0.256; P = 0.001). Additionally, the hippocampus volume was initially increased and then decreased at age of 50, mainly in the granule cell layer of the dentate gyrus (GC-DG), cornus ammonis 2/3 (CA2/3), CA4, and fissure (R2 > 0.16; P ≤ 0.001). The volumes of the putamen, pallidum, accumbens area, amygdala and caudate showed no significance with aging (R2 < 0.16; P > 0.001). DATA CONCLUSION: The results comprehensively show the relationships between age and cerebral structures in multiple brain regions, and these findings may help identify normal aging and other age-related neuroradiological disorders. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:152-163.
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Envelhecimento , Mapeamento Encefálico/métodos , Substância Cinzenta/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Feminino , Voluntários Saudáveis , Hipocampo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão , Adulto JovemRESUMO
Polyvinyl chloride (PVC) is a commonly used tissue-mimicking material (TMM) for phantom construction using 3D printing technology. PVC-based TMMs consist of a mixture of PVC powder and dioctyl terephthalate as a softener. In order to allow the clinical use of a PVC-based phantom use across CT and magnetic resonance imaging (MRI) imaging platforms, we evaluated the mechanical and physical imaging characteristics of ten PVC samples. The samples were made with different PVC-softener ratios to optimize phantom bioequivalence with physiologic human tissue. Phantom imaging characteristics, including computed tomography (CT) number, MRI relaxation time, and mechanical properties (e.g., Poisson's ratio and elastic modulus) were quantified. CT number varied over a range of approximately -10 to 110 HU. The relaxation times of the T1-weighted and T2-weighted images were 206.81 ± 17.50 and 20.22 ± 5.74 ms, respectively. Tensile testing was performed to evaluate mechanical properties on the three PVC samples that were closest to human tissue. The elastic moduli for these samples ranged 7.000-12.376 MPa, and Poisson's ratios were 0.604-0.644. After physical and imaging characterization of the various PVC-based phantoms, we successfully produced a bioequivalent phantom compatible with multimodal imaging platforms for machine calibration and image optimization/benchmarking. By combining PVC with 3D printing technologies, it is possible to construct imaging phantoms simulating human anatomies with tissue equivalency.
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Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/instrumentação , Imagens de Fantasmas , Cloreto de Polivinila/química , Radiografia Torácica , Tomografia Computadorizada por Raios X/métodos , Humanos , Imageamento por Ressonância Magnética/instrumentação , Tomografia Computadorizada por Raios X/instrumentaçãoRESUMO
Objective To observe the effect of Qili Qiangxin Capsule (QQC) in improving lung struc- tural remodeling on heart failure (HF) rats after myocardial infarction (Ml) and to study its possible mecha- nism. Methods The proximal left anterior descending branch of coronary artery was ligated using a terylene suture to establish acute myocardial infarction (AMI) rat model. After successful AMI modeling rats were ran- domly divided into the model group (intragastrically administered with distilled water at 1 mL/100 g, n =13) and the QQC group (intragastrically administered with QQC at the daily dose of 1 g/kg, n =9). And the sham-opera- tion group (intragastrically administered with distilled water at 1 mL/100 g, n =10) was also set up. After four weeks intervention heart functions of rats were detected using echocardiography. The pathological changes of lung structures were observed by HE and Masson staining method. Protein expressions of lung α-SMA, Collagen I, TGF-ß1, and p-Smad3 of the lung tissue were detected by immunohistochemistry and Western blot. Re- sults Compared with the sham-operation group, ejection fraction (EF) and fraction shortening (FS) decreased (P <0. 05) , protein expressions of lung left ventricular internal diastolic diameter (LVIDd), left ventric- ular internal systolic diameter (LVIDs), end diastolic volume (EDV), end systolic volume (ESV), α-smooth muscle actin (a-SMA), Collagen I, tumor growth factor-ß1 (TGF-ß1), and p-Smad3 increased (P <0.05) in the model group. The muscularized small arteries ratio and collagen area of the lung tissue increased in the model group (P <0. 05). Compared with the model group, EF and FS increased (P <0. 05), protein expressions of LVIDs, ESV, α-SMA, Collagen I, TGF-ß, , and p-Smad3 decreased (P <0.05) in the QQC group. The muscular- ized small arteries ratio and collagen area of the lung tissue decreased in the QQC group (P <0. 05). Conclusion QQC could improve lung structural remodeling degree of HF rats after MI, and its possible mechanism might be achieved by regulating TGF-beta,/Smad3 signaling pathways.
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Medicamentos de Ervas Chinesas , Infarto do Miocárdio , Remodelação Ventricular , Animais , Medicamentos de Ervas Chinesas/farmacologia , Coração , Insuficiência Cardíaca , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Remodelação Ventricular/efeitos dos fármacosRESUMO
OBJECTIVES: High-throughput sequencing technology is increasingly applied in intestinal microbiota of aquatic animals including shrimp. However, there is a lack of standard method or kit for DNA isolation from shrimp intestinal microbiota, and little is known about the effectiveness and biases regarding DNA extraction based on high-throughput sequencing. The aim of this study was to study the biases of different DNA extraction kits on community structure of shrimp intestinal microbiota through high-throughput sequencing, and to better understand the structure and composition of bacterial flora associated with healthy Litopenaeus vannamei. METHODS: We extracted the total DNA of intestinal microbiota from L. vannamei with three commercial kits designed for DNA extraction from bacteria, stool and tissue (Omega, USA). DNA quality was evaluated based on the absorbance ratios of 260/280 nm by NanoDrop, while DNA concentration was quantified using PicoGreen. Then Illumina MiSeq high-throughput sequencing was used to examine the intestinal bacterial communities following PCR amplification of 16S rDNA V4 region. RESULTS: The yield and purity of the DNA from the Bacterial Kit (SIB) were superior to those from the Stool Kit (SIS), whereas the DNA from Tissue Kit (SIT) presented too small amount to be amplified efficiently. The average sequence reads obtained from SIB and SIS samples were 52151 ± 5085 and 55296 ± 5147 respectively. After resampling at the same depth of 46800 reads, the operational taxonomic unit (OTU) number and Shannon diversity index of SIS samples were significantly higher than those of SIB samples. By contrast, the reproducibility of OTU among SIB replicates was higher than that among SIS replicates. The dominant phyla of SIS and SIB samples were identical, including Proteobacteria, Firmicutes, Bacteroidetes, Planctomycetes, Actinobacteria, and Cyanobacteria. However, the relative abundances of almost all the dominant groups at various taxonomic levels differed greatly between these two samples. CONCLUSION: Significant biases on community structure of shrimp intestinal microbiota were detected which originated from DNA extraction. And the core microbiota of the healthy L. vannamei in this study was mainly composed of genera Photobacterium, Lactococcus, Aliivibrio, Vibrio, as well as three other unclassified groups.
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Métodos Analíticos de Preparação de Amostras/normas , Bactérias/isolamento & purificação , DNA Bacteriano/isolamento & purificação , Microbioma Gastrointestinal , Penaeidae/microbiologia , Métodos Analíticos de Preparação de Amostras/métodos , Animais , Bactérias/classificação , Bactérias/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificaçãoAssuntos
Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Objectives: To determine whether contrast-enhanced CT radiomics features can preoperatively predict lymphovascular invasion (LVI) and perineural invasion (PNI) in gastric cancer (GC). Methods: A total of 148 patients were included in the LVI group, and 143 patients were included in the PNI group. Three predictive models were constructed, including clinical, radiomics, and combined models. A nomogram was developed with clinical risk factors to predict LVI and PNI status. The predictive performance of the three models was mainly evaluated using the mean area under the curve (AUC). The performance of three predictive models was assessed concerning calibration and clinical usefulness. Results: In the LVI group, the predictive power of the combined model (AUC=0.871, 0.822) outperformed the clinical model (AUC=0.792, 0.728) and the radiomics model (AUC=0.792, 0.728) in both the training and testing cohorts. In the PNI group, the combined model (AUC=0.834, 0.828) also had better predictive power than the clinical model (AUC=0.764, 0.632) and the radiomics model (AUC=0.764, 0.632) in both the training and testing cohorts. The combined models also showed good calibration and clinical usefulness for LVI and PNI prediction. Conclusion: CECT-based radiomics analysis might serve as a non-invasive method to predict LVI and PNI status in GC.
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Epithelial ovarian cancer (EOC) is a fatal gynecological malignant tumor with a low 5-year survival rate. The use of the first-line chemotherapeutic drug, paclitaxel, for the treatment of EOC is associated with resistance, often leading to treatment failure. The present study investigated the gene targets in an A2780 paclitaxel-resistant EOC cell line (A2780/Taxol), and the potential underlying mechanisms using transcriptome sequencing technology and bioinformatics analysis. The transcriptome of the A2780/Taxol cell line was sequenced, and 498 differentially expressed genes were obtained contained in the Gene Expression Omnibus dataset. Further bioinformatics analysis revealed that matrix metalloproteinase 1 (MMP1), zyxin (ZYX) and Unc-5 netrin receptor C (UNC5C) may be gene targets related to paclitaxel resistance. Moreover, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that a potential mechanism associated with paclitaxel resistance was related to cell migration. Furthermore, the expression levels of MMP1, ZYX and UNC5C were verified using western blotting, immunofluorescence and immunohistochemistry in vitro. The results revealed that the expression levels of MMP1 and ZYX were significantly increased in A2780/Taxol cells, while UNC5C expression was significantly decreased, which was consistent with the results of the transcriptome sequencing. The present study demonstrated that MMP1, ZYX and UNC5C may be the gene targets associated with paclitaxel resistance in EOC. These genes have potential to be used as molecular markers for EOC drug therapy, targeted elimination of drug resistance, and evaluation of treatment efficacy and patient prognosis.
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PURPOSE: To develop a combined radiomics nomogram based on computed tomography (CT) images and clinical features to preoperatively distinguish Lauren's diffuse-type gastric cancer (GC) from intestinal-type GC. METHODS: Ninety-five patients with Lauren's intestinal or diffuse-type GC confirmed by postoperative pathology had their preoperative clinical information and dynamic contrast CT images retrospectively analyzed and were subdivided into training and test groups in a 7:3 ratio. To select the optimal features and construct the radiomic signatures, we extracted, filtered, and minimized the radiomic features from arterial phase (AP) and venous phase (VP) CT images. We constructed four models (clinical model, AP radiomics model, VP radiomics model, and radiomics-clinical model) to assess and compare their predictive performance between the intestinal- and diffuse-type GC. Receiver-operating characteristic (ROC) curve, area under the ROC curve (AUC), and the DeLong test were used for assessment and comparison. In this study, radiomic nomograms integrating combined radiomic signatures and clinical characteristics were developed. RESULTS: Compared to the AP radiomics model, the VP radiomics model had better performance, with an AUC of 0.832 (95% confidence interval [CI], 0.735, 0.929) in the training cohort and 0.760 (95% CI 0.580, 0.940) in the test cohort. Among the combined models that assessed Lauren's type GC, the model including age and VP radiomics showed the best performance, with an AUC of 0.849 (95% CI 0.758, 0.940) in the training cohort and 0.793 (95% CI 0.629, 0.957) in the test cohort. CONCLUSIONS: Nomogram incorporating radiomic signatures and clinical features effectively differentiated Lauren's diffuse-type from intestinal-type GC.
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Nomogramas , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Curva ROC , Tomografia Computadorizada por Raios X/métodosRESUMO
OBJECTIVE: To shorten acquisition time of readout segmentation of long variable echo trains (RESOLVE)-based diffusion kurtosis imaging (DKI) via Readout Partial Fourier (RPF) and b-value combinations. METHODS: The RESOLVE-based DKI images of 38 patients with nasopharyngeal carcinoma (NPC) were prospectively enrolled. For RESOLVE-based DKI images with 5/8 RPF and without RPF, objective and subjective evaluations of image quality were performed. A total of nine groups with different b-value combinations were simulated, and the influence of different b-value combinations for RESOLVE-RPF-based DKI sequences was assessed using the intraclass correlation coefficient (ICC). RESULTS: The mean values of signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in DKI images without RPF were higher than those with 5/8 RPF (252.9 ± 77.7 vs 247.3 ± 85.5 and 5.8 ± 2.8 vs 5.4 ± 2.3, respectively), but not significantly (p = 0.460 and p = 0.180, respectively). In comparing the ICCs between nine groups of different b-value combinations in RESOLVE-RPF-based DKI, group (200, 800, 2000 s/mm2), group (200, 400, 800, 2000 s/mm2) and group (200, 800, 1500, 2000 s/mm2) were not significantly different (p > 0.001) and showed excellent agreement (0.81-1.00) with that of group (200, 400, 800, 1500, 2000 s/mm2). Using b-value optimization and RPF technology, the group with RPF (200, 400, 800, 2000 s/mm2) showed a 56% reduced scanning compared with the group without RPF (200, 400, 800, 1500, 2000 s/mm2; 3 min 46 s vs 8 min 31 s, respectively). CONCLUSION: DKI with RPF did not significantly affect image quality, but both RPF and different b-value combinations can affect the scanning time. The combination of RPF and b-value optimization can ensure the stability of DKI parameters and reduce the scanning time by 56%. ADVANCES IN KNOWLEDGE: This work is to optimize scan parameters, e.g. RPF and b-value combinations, to reduce acquisition time for RESOLVE-based DKI in NPC. To our knowledge, the effect of RESOLVE-RPF and b-value combinations on DKI has not been reported.
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Imagem de Difusão por Ressonância Magnética , Neoplasias Nasofaríngeas , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão , Humanos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Razão Sinal-RuídoRESUMO
The conventional method of preparing metal-ceramic composite structures causes delamination and cracking defects due to differences in the composite structures' properties, such as the coefficient of thermal expansion between metal and ceramic materials. Laser-directed energy deposition (LDED) technology has a unique advantage in that the composition of the materials can be changed during the forming process. This technique can overcome existing problems by forming composite structures. In this study, a multilayer composite structure was prepared using LDED technology, and different materials were deposited with their own appropriate process parameters. A layer of Al2O3 ceramic was deposited first, and then three layers of a NbMoTa multi-principal element alloy (MPEA) were deposited as a single composite structural unit. A specimen of the NbMoTa-Al2O3 multilayer composite structure, composed of multiple composite structural units, was formed on the upper surface of a φ20 mm × 60 mm cylinder. The wear resistance was improved by 55% compared to the NbMoTa. The resistivity was 1.55 × 10-5 Ω × m in the parallel forming direction and 1.29 × 10-7 Ω × m in the vertical forming direction. A new, electrically anisotropic material was successfully obtained, and this study provides experimental methods and data for the preparation of smart materials and new sensors.
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A series of aromatic acetic acid compounds were designed and synthesized on the basis of Non-steroidal anti-inflammatory drugs indomethacin and diclofenac. Compounds 5a, 7a, 5h, 7h and 17 could strongly promote insulin-regulated differentiation of 3T3-L1 cells in vitro. They acted as full or partial PPARgamma agonist, or improved insulin resistance through non-PPARgamma pathway.
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Diclofenaco/farmacologia , Indometacina/farmacologia , Resistência à Insulina , Células 3T3-L1 , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Diclofenaco/química , Desenho de Fármacos , Indometacina/química , Insulina/farmacologia , Camundongos , PPAR gama/agonistas , PPAR gama/metabolismo , RatosRESUMO
To fabricate an individualized anthropomorphic lung phantom with tissue-equivalent radiation attenuation properties using a cost-effective three-dimensional (3D) printing technique. Based on anonymized human chest CT images, the phantom contained a 3D-printed skin shell, filled with tissue equivalent materials with similar radiation attenuation characteristics. The filling materials were a mixture of CaCO3, MgO, agarose, NaCl, pearl powder and silica gel. The dose calculation accuracy of different treatment planning system (TPS) algorithms was validated and compared with the ion chamber measurements in the phantom, including tumor and surrounding normal tissues. The chest phantom was shown to represent a human's chest in terms of radiation attenuation property and human anatomy. The Hounsfield unit ranges were -60 to -100, 20 to 60, and 120 to 300 for fat, muscle, and bone, respectively. The actual measured values of the ionization chamber were 213.7 cGy for the tumor, 53.85 cGy for normal lung tissue, and 4.1 cGy for the spinal cord, compared to 214.1, 55.2, and 4.5 cGy, respectively, with use of the Monte Carlo algorithm in TPS. The application of 3D printing in anthropomorphic phantoms can improve personalized medical need and efficiency with reduce costs thus, can be used for radiation dose verification.
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PURPOSE: Circulating tumour cells (CTCs) have been found to correlate with treatment response and prognosis in some cancers; however, such correlations have not been reported in nasopharyngeal carcinoma (NPC). We aimed to determine the relationship between CTCs and the treatment response in NPC. PATIENTS AND METHODS: In this prospective study, we ascertained the karyotype of CTCs and identified a possible correlation between karyotype and treatment response in locally advanced NPC (LANPC). We prospectively collected peripheral blood from LANPC patients. CTCs were measured by negative enrichment with immunofluorescence in situ hybridization (imFISH) and a centromere of chromosome 8 (CEP8) probe. Chromosome 8 was karyotyped in CTCs, which were identified as triploid, tetraploid or multiploid. Patients were then treated with platinum-based induction chemotherapy followed by concurrent chemoradiotherapy. CTCs were measured before and after treatment. RESULTS: We detected CTCs in 27 of 50 (54%) patients, which served as a baseline value. The results were independent of age, smoking history and NPC clinical stage. All of the 27 evaluable enrolled patients with detectable CTCs showed decreases in both total CTCs and CTCs of different ploidies after treatment (P<0.05). Reductions in CTCs were significantly more common in patients with a complete response (CR) than in those with a partial response (PR) (P<0.05). The presence of fewer tetraploid CTCs before treatment had a positive predictive value for a CR to chemoradiotherapy (P<0.05). CTC-positive patients had a shorter PFS after treatment (P=0.03). CONCLUSION: The decrease in CTCs was correlated with therapeutic efficacy in patients with LANPC, and the presence of tetraploid CTCs before treatment is a potential predictive factor for clinical outcomes.
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BACKGROUND: Breast imaging technology plays an important role in breast cancer planning and treatment. Recently, three-dimensional (3D) printing technology has become a trending issue in phantom constructions for medical applications, with its advantages of being customizable and cost-efficient. However, there is no current practice in the field of multi-purpose breast phantom for quality control (QC) in multi-modalities imaging. The purpose of this study was to fabricate a multi-purpose breast phantom with tissue-equivalent materials via a 3D printing technique for QC in multi-modalities imaging. METHODS: We used polyvinyl chloride (PVC) based materials and a 3D printing technique to construct a breast phantom. The phantom incorporates structures imaged in the female breast such as microcalcifications, fiber lesions, and tumors with different sizes. Moreover, the phantom was used to assess the sensitivity of lesion detection, depth resolution, and detectability thresholds with different imaging modalities. Phantom tissue equivalent properties were determined using computed tomography (CT) attenuation [Hounsfield unit (HU)] and magnetic resonance imaging (MRI) relaxation times. RESULTS: The 3D-printed breast phantom had an average background value of 36.2 HU, which is close to that of glandular breast tissue (40 HU). T1 and T2 relaxation times had an average relaxation time of 206.81±17.50 and 20.22±5.74 ms, respectively. Mammographic imaging had improved detection of microcalcification compared with ultrasound and MRI with multiple sequences [T1WI, T2WI and short inversion time inversion recovery (STIR)]. Soft-tissue lesion detection and cylindrical tumor contrast were superior with mammography and MRI compared to ultrasound. Hemispherical tumor detection was similar regardless of the imaging modality used. CONCLUSIONS: We developed a multi-purpose breast phantom using a 3D printing technique and determined its value for multi-modal breast imaging studies.
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For in-depth characterization of the microbiota associated with shrimp larvae, careful selection of DNA isolation procedure is paramount for avoiding biases introduced in community profiling. Four E.Z.N.A.™ DNA extraction kits, i.e., Bacterial, Mollusc, Stool, and Tissue DNA Kits, abbreviated as Ba, Mo, St, and Ti, respectively, were initially evaluated with zoea 2 (Z2) larvae of the Pacific white shrimp (Litopenaeus vannamei) by 16S amplicon sequencing on a Illumina MiSeq platform. Further characterization of additional larval samples, specifically nauplii 5 (N5), mysis 1 (M1), and postlarvae 1 (P1), was performed with Ba and St kits to examine the changing microbiota profile during shrimp hatchery period. The results from the Z2 samples showed that DNA yields from the four kits varied significantly (P < 0.05), whereas no significant differences were detected in the α-diversity metrics of the microbiota. By contrast, the St kit, with the lowest DNA yield and quality, successfully recovered DNA from Gram-positive and gut-associated bacterial groups, whereas the Ba kit, which showed maximal microbiota similarity with the Mo kit, manifested the best reproducibility. Notably, significant differences were observed in relative abundances of most dominant taxa when comparing results from the Ba and St kits on Z2, M1, and P1 samples. In addition, the bacterial community identified shifted markedly with larval development regardless of the DNA extraction kits. The DNA recovery biases arising from the larval microbiota could be due to different protocols for cell lysis and purification. Therefore, combined application of different DNA extraction methods may facilitate identification of some biologically important groups owing to their complementary effects. This approach should receive adequate attention for a thorough understanding of the larvae-associated microbiota of the penaeid shrimp.
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Routine follow-up visits and radiographic imaging are required for outcome evaluation and tumor recurrence monitoring. Yet more personalized surveillance is required in order to sufficiently address the nature of heterogeneity in nonsmall cell lung cancer and possible recurrences upon completion of treatment. Radiomics, an emerging noninvasive technology using medical imaging analysis and data mining methodology, has been adopted to the area of cancer diagnostics in recent years. Its potential application in response assessment for cancer treatment has also drawn considerable attention. Radiomics seeks to extract a large amount of valuable information from patients' medical images (both pretreatment and follow-up images) and quantitatively correlate image features with diagnostic and therapeutic outcomes. Radiomics relies on computers to identify and analyze vast amounts of quantitative image features that were previously overlooked, unmanageable, or failed to be identified (and recorded) by human eyes. The research area has been focusing on the predictive accuracy of pretreatment features for outcome and response and the early discovery of signs of tumor response, recurrence, distant metastasis, radiation-induced lung injury, death, and other outcomes, respectively. This review summarized the application of radiomics in response assessments in radiotherapy and chemotherapy for non-small cell lung cancer, including image acquisition/reconstruction, region of interest definition/segmentation, feature extraction, and feature selection and classification. The literature search for references of this article includes PubMed peer-reviewed publications over the last 10 years on the topics of radiomics, textural features, radiotherapy, chemotherapy, lung cancer, and response assessment. Summary tables of radiomics in response assessment and treatment outcome prediction in radiation oncology have been developed based on the comprehensive review of the literature.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde/métodos , Mineração de Dados/métodos , Humanos , Medicina de Precisão/métodos , Radioterapia (Especialidade)/métodosRESUMO
Qili qiangxin capsule (QL), a traditional Chinese herbal compound, has been proved to be effective and safe for the treatment of chronic heart failure (CHF). Upregulation of aquaporin-2 (AQP2) accounts for the water retention in CHF. The aim of the present study was to evaluate the effects of QL on the expression of AQP2 in rats with CHF induced by acute myocardial infarction and to investigate the underlying mechanisms. The urine output of all rats was quantified and collected every day at the first week and the 4th week after administration of QL or Valsartan. The expression of AQP2, vasopressin type 2 receptor (V2R), and angiotensin II type 1 receptor (AT1R) were examined after treatment for 4 weeks. Urinary output increased significantly after administration of QL. Importantly, the protein expression of AQP2 and AQP2 phosphorylated at serine 256 (pS256-AQP2) was downregulated after administration of QL and Valsartan to CHF rats. Furthermore, QL reduced plasma arginine vasopressin (AVP) and angiotensin II (AngII) level and downregulated V2R and AT1R protein expression. Thus, QL exerts its diuretic effect and improves cardiac function in CHF rats by reversing the increases in both AQP2 and pS256-AQP2 expression. The possible mechanisms may involve inhibition of V2R and AT1R.