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BACKGROUND: Microsatellite instability (MSI), caused by mismatch repair (MMR) protein defects that lead to uncorrectable mismatch bases, results in the accumulation of gene mutations and ultimately to tumors. Preoperative prediction of MSI can provide a basis for personalized and precise treatment of endometrial cancer (EC) patients. PURPOSE: To investigate amide proton transfer weighting (APTw) imaging combined with intravoxel incoherent motion (IVIM) in the assessment of MSI in EC. STUDY TYPE: Retrospective. POPULATION: A total of 71 patients with EC (12 classified as the MSI group and 22 as the microsatellite stabilization [MSS] group after entering and leaving the group standard). FIELD STRENGTH/SEQUENCE: A 3.0 T/IVIM, diffusion-weighted imaging (DWI) and APTw. ASSESSMENT: Amide proton transfer (APT) value, apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) were calculated and compared between MSI and MSS groups. STATISTICAL TESTS: The Kendall's W test; Mann-Whitney U-test; Chi-square test or Fisher's exact test; logistic regression analysis; Area under the receiver operating characteristic (ROC) curve (AUC); The Delong test; Pearson or Spearman correlation coefficients. The significance threshold was set at P < 0.05. RESULTS: APT and D* values of the MSI group were significantly higher than those of the MSS group. While ADC, D, and f values in the MSI group were significantly lower than those in the MSS group. The multivariate analysis revealed that only APT and D* values were independent predictors to evaluate the MSI status. And the ROC curves indicated that the combination of APT and D* values could distinguish the MSI status of EC with the highest diagnostic efficacy (AUC = 0.973), even without significant difference to those by APT (AUC = 0.894) or D* (AUC = 0.920) value separately (P = 0.149 and 0.078, respectively). CONCLUSION: Combination of APTw and IVIM imaging may serve as an effective noninvasive method for clinical assessment of MSI in EC. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.
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Neoplasias do Endométrio , Prótons , Feminino , Humanos , Instabilidade de Microssatélites , Amidas , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/genética , Movimento (Física)RESUMO
Gap junctions (GJs), which are composed of connexins (Cxs), provide channels for direct information exchange between cells. Cx expression has a strong spatial specificity; however, its influence on cell behavior and information exchange between cells cannot be ignored. A variety of factors in organisms can modulate Cxs and subsequently trigger a series of responses that have important effects on cellular behavior. The expression and function of Cxs and the number and function of GJs are in dynamic change. Cxs have been characterized as tumor suppressors in the past, but recent studies have highlighted the critical roles of Cxs and GJs in cancer pathogenesis. The complex mechanism underlying Cx and GJ involvement in cancer development is a major obstacle to the evolution of therapy targeting Cxs. In this paper, we review the post-translational modifications of Cxs, the interactions of Cxs with several chaperone proteins, and the effects of Cxs and GJs on cancer. Video Abstract.
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Conexinas , Neoplasias , Humanos , Conexinas/metabolismo , Conexinas/farmacologia , Junções Comunicantes/metabolismo , Neoplasias/metabolismoRESUMO
Chondrogenesis is the formation of chondrocytes and cartilage tissues and starts with mesenchymal stem cell (MSC) recruitment and migration, condensation of progenitors, chondrocyte differentiation, and maturation. The chondrogenic differentiation of MSCs depends on co-regulation of many exogenous and endogenous factors including specific microenvironmental signals, non-coding RNAs, physical factors existed in culture condition, etc. Cancer stem cells (CSCs) exhibit self-renewal capacity, pluripotency and cellular plasticity, which have the potential to differentiate into post-mitotic and benign cells. Accumulating evidence has shown that CSCs can be induced to differentiate into various benign cells including adipocytes, fibrocytes, osteoblast, and so on. Retinoic acid has been widely used in the treatment of acute promyelocytic leukemia. Previous study confirmed that polyploid giant cancer cells, a type of cancer stem-like cells, could differentiate into adipocytes, osteocytes, and chondrocytes. In this review, we will summarize signaling pathways and cytokines in chondrogenic differentiation of MSCs. Understanding the molecular mechanism of chondrogenic differentiation of CSCs and cancer cells may provide new strategies for cancer treatment.
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OBJECTIVE: This study aimed to elucidate the difference in diffusion-weighted magnetic resonance imaging (DWI) and diffusion tensor imaging (DTI) parameters between endometrioid endometrial adenocarcinoma (EEA) and uterine serous adenocarcinoma (SA). METHODS: Data of patients with pathologically confirmed EEA or SA who underwent DWI and DTI scanning between May 2013 and July 2016 were retrospectively analyzed. Apparent diffusion coefficient (ADC) value from DWI and ADC from DTI (ADC) map and fractional anisotropy (FA) values from DTI were analyzed and compared statistically. The correlation between ADC and ADC was analyzed by Pearson correlation analysis. Apparent diffusion coefficient, ADC, and FA between the 2 groups were compared using independent t test. The effect of ADC, ADC, and FA in distinguishing EEA and SA was evaluated by receiver operator characteristic curve. RESULT: Thirty-three patients were enrolled into the study, including 13 cases of SA and 20 cases of EEA. Pearson correlation analysis suggested that the value of ADC was highly related with ADC in both the SA group (r = 0.812, P = 0.001) and the EEA group (r = 0.858, P < 0.001). The value of ADC and ADC in the SA group was significantly lower than that in the EEA group; FA was significantly higher than that in the EEA group. Receiver operator characteristic curve analysis showed that ADC and ADC have high sensitivity and specificity; FA has low sensitivity and high specificity. CONCLUSIONS: We suggest that both DWI and DTI could be used in distinguishing EEA from SA. Apparent diffusion coefficient and ADC possess potential diagnostic value with high sensitivity and specificity.
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Carcinoma Endometrioide/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Feminino , Humanos , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVE: To explore the application value of dual-energy spectral imaging scanning with low radiation dose and low-concentration contrast medium (270 mg I/mL) in abdominal CT angiography (CTA) of obese patients. METHODS: A total of 127 obese patients (BMI≥25 kg/m(2) and waist circumference ≥900 mm) referred for abdominal CTA were prospectively enrolled in the study. The patients were divided into two groups; in group A (n=69), a spectral imaging scan mode and 270 mg I/mL iodine concentration contrast medium was used, and in group B (n=58), a conventional imaging scan mode using 120 kVp and 350 mg I/mL iodine concentration contrast medium was used. The image quality of the right renal artery in the two groups was evaluated by two observers using a 5-point scale, and the scores were compared using the Mann-Whitney U-test; the inter-observer agreement for the scores was analysed using the Kappa test. The CT values of the abdominal aorta, the superior mesenteric artery, the common hepatic artery and the splenic artery, and the CT value and standard deviation (SD) of the erector spinae at the level of the right renal hilum in groups A and B were measured by two observers; the inter-observer agreement of the measurement data was analysed using the inter-class correlation coefficient test. The following parameters were compared between the two groups using an independent sample t-test: the CT values of the abdominal aorta and its main branches; the image contrast-to-noise ratio (CNR) and figure of merit (FOM) of the abdominal aorta; the CT dose index (CTDIvol ); the dose length product (DLP); and the total iodine intake of the patients. P<.05 suggested a statistically significant difference. RESULTS: The image scores of the right renal artery in groups A (4.59±0.60) and B (4.53±0.63) were the same (P=.57), with good inter-observer agreement. The CT values of the abdominal aorta, the superior mesenteric artery, the common hepatic artery and the splenic artery were >300 HU in both the groups; there was no statistically significant difference between the two groups (all P>.05), and inter-observer agreement was also good. Group A had significantly higher CNR and FOM values in the abdominal aorta than group B (all P<.001). Compared with group B, the CTDIvol and DLP values in group A were decreased by 46% and 35%, respectively. The total iodine intake for patients in group A was 27 g, 23% lower than the 35 g intake for patients in group B. CONCLUSION: Compared with conventional CT, spectral CT imaging significantly reduces both radiation dose and contrast dose while maintaining image quality in abdominal CTA for patients with central obesity and high BMI.
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Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Obesidade/diagnóstico por imagem , Absorciometria de Fóton/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/diagnóstico por imagem , Estudos de Viabilidade , Artéria Hepática/diagnóstico por imagem , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Pessoa de Meia-Idade , Obesidade/complicações , Radiografia Abdominal/métodos , Artéria Renal/diagnóstico por imagem , Artéria Esplênica/diagnóstico por imagemRESUMO
BACKGROUND: To determine the clinical value of apparent diffusion coefficient (ADC) measurement by diffusion weighted magnetic resonance imaging (DW-MRI) in differentiating renal tumors. METHODS: Electronic databases were searched using combinations of keywords and free words relating to renal tumor, ADC and DW-MRI. Based on carefully selected inclusion and exclusion criteria, relevant case-control studies were identified and the related clinical data was acquired. Statistical analyses were performed using STATA 12.0 (Stata Corporation, College station, TX). RESULTS: Sixteen case-control studies were ultimately included in the present meta-analysis. These 16 high quality studies contained a combined total of 438 normal renal tissues and 832 renal tumor lesions (597 malignant and 235 benign). The results revealed that ADC values of malignant renal tumor tissues were markedly lower than normal renal tissues and benign renal tumor tissues. ADC values of benign renal tumor tissues were also significantly lower than normal renal tissue. CONCLUSIONS: ADC measurement by DW-MRI provided clinically useful information on the internal structure of renal tumors and could be an important radiographic index for differentiation of malignant renal tumors from benign renal tumors.
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Imagem de Difusão por Ressonância Magnética , Neoplasias Renais/diagnóstico , Estudos de Casos e Controles , Bases de Dados Factuais , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Viés de Publicação , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To evaluate the feasibility of enhanced T2 star-weighted angiography (ESWAN) in differentiating endometrial from non-endometrial cysts. METHODS: Forty-nine patients with 60 histopathologically proven ovarian cystic lesions underwent pelvic MRI including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), liver acquisition with volume acceleration, and ESWAN. Ovarian cystic lesions were divided into endometrial cysts (group 1; n = 28), pyosalpinx and hydrosalpinx (group 2; n = 13), and ovarian cystic and cystic-solid tumors (group 3; n = 19). R2* (effective transverse relaxation rate) values were measured and pairwise comparison of the R2* values among the three groups was made using Kruskal-Wallis test. Receiver operating characteristic curves were used to calculate cutoff values and performance of R2* values for distinguishing among groups. T1WI signal intensity and R2* value were also compared using area under curve values. RESULTS: R2* values for group 1 were statistically higher than groups 2 and 3 (15.37, 1.40, and 1.79 Hz, respectively; P < 0.001). The cutoff value for R2* was 7.43 Hz with a sensitivity, specificity, PPV, NPV, and accuracy of 96.43, 87.50, 87.10, 96.55, and 91.67%, respectively. There was no significant difference between the R2* value and T1WI in diagnosing endometrial cysts. CONCLUSIONS: The R2* value provides an effective way to discriminate endometrial cysts from other ovarian cystic lesions.
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Meios de Contraste , Endometriose/complicações , Endometriose/patologia , Aumento da Imagem , Cistos Ovarianos/etiologia , Cistos Ovarianos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Ovário/patologia , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
OBJECTIVE: To qualitatively and quantitatively evaluate the feasibility of CT virtual unenhanced (VUE) spectral imaging in renal cell carcinoma. METHOD: Thirty-six patients with histopathologically proven renal cell carcinoma underwent gemstone spectral imaging (GSI) including ture unenhanced (TUE), arterial, cortex and medullary phase acquisitions. The triphasic GSI dataset was sent to workstation and 3 sets of VUE images (including VUE a, VUE c, VUE m) were obtained by subtract iodine from iodine-water images in the triphasic enhanced GSI images, respectively. The quality of VUE s and TUE images was evaluated on a five-point scale.Interobserver agreement with regard to image quality was assessed using Cohen's Kappa, and four groups of image quality was compared with ANOVA analysis. The contrast-to-noise ratio (CNR) of mass-to-kidney in the TUE and VUE s images was calculated, and difference between these four datasets was compared with ANOVA analysis. Using appearance of masses on triphasic images as a standard, the masses detection ratio of four groups was calculated and compared with chi-square test. RESULTS: Interobserver agreement with regard to image quality was excellent (κ>0.600). There was no significant difference among the image quality of TUE and triphasic images of VUEs (P>0.05). The CNR of TUE (0.7 ± 0.6) was significant worse than that of triphasic images (1.7 ± 1.0, 1.9 ± 1.2, 2.5 ± 1.4, respectively) (P<0.05). There was no significant difference among the CNR of triphasic images (P>0.05). CONCLUSION: VUE images obtain from triphasic phases may be a surrogate for conventional unenhanced scan in renal cell carcinoma diagnosis.
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Carcinoma de Células Renais , Neoplasias Renais , Tomografia Computadorizada por Raios X , HumanosRESUMO
OBJECTIVE: To assess the image quality of gastrointestinal tract malignant tumors arteries using low tube voltage, low contrast medium concentration and 50% adaptive statistical iterative reconstruction (ASiR) algorithm. METHODS: A total of 58 patients with pathologically confirmed gastrointestinal tract malignant tumors and body mass index (BMI) under 22 kg/m² undergoing computed tomography (CT) scanning during March-December 2013. They were randomly divided into group A (270 mgI/ml of contrast medium, 80 kVp tube voltage scanning and 50% ASiR; 21 males and 11 females with an age range of 40-90 years) and group B (350 mgI/ml of contrast medium, 120 kVp routine tube voltage; 22 males and 4 females with an age range of 40-76 years). The inter-group differences of age and gender ratio were compared with Mann-Whitney U and Fisher exact tests respectively. Two independent radiologists reviewed reconstructions and separated the reconstructed image into 5 points according to image quality. The CT value of tumor blood supplying artery (CT1 value) and fat in anterior abdominal wall (SD value) were measured and image noise, contrast-to-noise ratio (CNR) and figure of merit (FOM) calculated. The interobserver variation was estimated by weighted kappa statistics and intra-class correlation coefficients (ICC) test. The point of image quality of two groups was compared by Mann-Whitney U test. The paired Student t test was used to compare the inter-group differences in CT1, SD, CNR, FOM and CT dose index (CTDIvol). RESULTS: No inter-group difference existed in patient age or gender ratio. The consistency of two radiologists was excellent (kappa value > 0.80; ICC value > 0.75). The subjective image quality scores of tumor blood supplying arteries showed no inter-group difference (P = 0.09). The tumor blood supply arteries CT value, CNR and FOM of group A (459 ± 69 HU, 20.2 ± 3.3 and 85 ± 37) were significantly higher than those of group B (250 ± 42 HU, 9.3 ± 1.9 and 9 ± 4) (both P < 0.01). The SD value of group A (20.0 ± 1.7) was obviously lower than that of group B (22.4 ± 3.2) (P < 0.01). And the CTDIvol of group A (5.2 ± 1.2 mGy) was obviously lower than that of group B (13.5 ± 4.7 mGy) (P < 0.01). CONCLUSION: For patients of BMI ≤ 22 kg/m², low tube voltage and low contrast medium concentration scan condition with 50% ASiR algorithm is feasible for acquiring better quality image and ensuring significant reduction in effective dose.
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Neoplasias Gastrointestinais , Neovascularização Patológica , Doses de Radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Angiografia , Artérias , Índice de Massa Corporal , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To explore the application of optimal monochromatic images according to computed tomography (CT) values of conventional CT scans with high concentration contrast agent and the feasibility in guiding abdominal arteries imaging with low concentration contrast. METHODS: From March 2013 to February 2014, 160 patients of suspected celiac disease with a body mass index (BMI) of >25 kg/m(2) underwent spectral CT scan. And they were randomly divided into two groups. In group A (n = 61), 270 mgI/ml low concentrations of contrast agents and spectral CT imaging; in group B (n = 99), 350 mgI/ml high concentrations of contrast agents and 120 kVp scan. For CT values of the first measurement of abdominal aorta B group of patients, the average CT value was calculated . The optimal monochromatic images of group A according to CT values of group B were reconstructed and 70 keV images (group C) also reconstructed. The CT values of hepatic, splenic, right renal and superior mesenteric arteries were measured and contrast to noise ratios (CNRs) calculated. CT values and CNR were compared through t test on independent samples. P > 0.05 indicated no significant difference. RESULTS: Mean CT value of abdominal aorta was (422 ± 65) HU in group B. And optimal keV was (67 ± 5) keV in group A. CT values of abdominal aorta and its branches showed no statistical significance; the CNRs of abdominal aorta and its branches showed statistical significance. The scoring consistency between two observers was excellent and the score (4.1 ± 0.9 vs 4.2 ± 0.7) showed no significant difference (P > 0.05). CONCLUSION: GSI abdominal scans with low concentration contrast may obtain better image qualities compared to conventional CTA of high concentration. And (67 ± 5) keV is recommended.
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Aorta Abdominal , Tomografia Computadorizada por Raios X , Meios de Contraste , Humanos , Artéria Mesentérica SuperiorRESUMO
OBJECTIVE: To investigate the value of amide proton transfer weighted (APTw) combined with diffusion kurtosis imaging (DKI) in quantitative prediction of lymph node metastasis (LNM) in cervical carcinoma (CC). METHODS: Data of 19 LNM(+) and 50 LNM(-) patients with CC were retrospectively analyzed. 3.0 T MRI scan was performed before the operation, including APTw and DKI. After post-processing, quantitative magnetization transfer ratio asymmetric at 3.5 ppm [MTRasym (3.5 ppm)], mean kurtosis (MK), and mean diffusivity (MD) maps were obtained. The MTRasym(3.5 ppm), MK, and MD values were respectively measured by two observers, and intra-class correlation coefficients (ICC) were used to test the consistency of the results. The independent samples t-test or Mann-Whitney U test was used to compare the differences in the values of each parameter. The ROC curve was used to analyze the predictive performance of parameters with significant differences and their combination parameter. RESULTS: The two observers had good agreement in the measurement of each data (ICC > 0.75). The MTRasym(3.5 ppm) and MK values of the LNM(+) group(3.260 ± 0.538% and 0.531 ± 0.202) were higher than those of the LNM(-) group(2.698 ± 0.597% and 0.401 ± 0.148) (P < 0.05), while there was no significant difference in MD values between the two groups(P > 0.05). The area under the curves (AUCs) of MTRasym(3.5 ppm), MK value, and MTRasym(3.5 ppm) + MK value were 0.763, 0.716, and 0.813, respectively, when predicting LNM status of CC. CONCLUSION: APTw and DKI can quantitatively predict LNM status of CC, which is of importance in clinical diagnosis and treatment.
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Prótons , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/diagnóstico por imagem , Amidas , Estudos Retrospectivos , Metástase Linfática/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodosRESUMO
High concentrations of cobalt chloride (CoCl2) can induce the formation of polyploid giant cancer cells (PGCCs) in various tumors, which can produce daughter cells with strong proliferative, migratory and invasive abilities via asymmetric division. To study the role of hypoxiainducible factor (HIF) 1α in the formation of PGCCs, colon cancer cell lines Hct116 and LoVo were used as experimental subjects. Western blotting, nuclear and cytoplasmic protein extraction and immunocytochemical experiments were used to compare the changes in the expression and subcellular localization of HIF1α, microphthalmiaassociated transcription factor (MITF), protein inhibitor of activated STAT protein 4 (PIAS4) and von HippelLindau disease tumor suppressor (VHL) after treatment with CoCl2. The SUMOylation of HIFα was verified by coimmunoprecipitation assay. After inhibiting HIF1α SUMOylation, the changes in proliferation, migration and invasion abilities of Hct116 and LoVo were compared by plate colony formation, wound healing and Transwell migration and invasion. In addition, lysine sites that led to SUMOylation of HIF1α were identified through site mutation experiments. The results showed that CoCl2 can induce the formation of PGCCs with the expression level of HIF1α higher in treated cells than in control cells. HIF1α was primarily located in the cytoplasm of control cell. Following CoCl2 treatment, the subcellular localization of HIF1α was primarily in the nuclei of PGCCs with daughter cells (PDCs). After treatment with SUMOylation inhibitors, the nuclear HIF1α expression in PDCs decreased. Furthermore, their proliferation, migration and invasion abilities also decreased. After inhibiting the expression of MITF, the expression of HIF1α decreased. MITF can regulate HIF1α SUMOylation. Expression and subcellular localization of VHL and HIF1α did not change following PIAS4 knockdown. SUMOylation of HIF1α occurs at the amino acid sites K391 and K477 in PDCs. After mutation of the two sites, nuclear expression of HIF1α in PDCs was reduced, along with a significant reduction in the proliferation, migration and invasion abilities. In conclusion, the posttranslation modification regulated the subcellular location of HIF1α and the nuclear expression of HIF1α promoted the proliferation, migration and invasion abilities of PDCs. MITF could regulate the transcription and protein levels of HIF1α and participate in the regulation of HIF1α SUMOylation.
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Cobalto , Fator de Transcrição Associado à Microftalmia , Neoplasias , Humanos , Fator de Transcrição Associado à Microftalmia/genética , Sumoilação , Linhagem Celular Tumoral , Poliploidia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Movimento Celular , Proliferação de CélulasRESUMO
OBJECTIVES: To find the optimal acceleration factor (AF) of the compressed SENSE (CS) technique for uterine isotropic high-resolution 3D T2-weighted imaging (3D-ISO-T2WI). METHODS: A total of 91 female volunteers from the First Affiliated Hospital of Dalian Medical University, Chu Hsien-I Memorial Hospital and Tianjin Institute of Endocrinology, and The Fourth Hospital of Harbin were recruited. A total of 44 volunteers received uterus sagittal 3D-ISO-T2WI scans on 3.0T MRI device with different CS AFs (including SENSE3, CS3, CS4, CS5, CS6, and CS7), 51 received 3D-ISO-T2WI scans with different degrees of fat suppression (none, light, moderate, and severe), while 4 volunteers received both series of scans. Image quality was subjectively evaluated with a 3-point scoring system. Junction zone signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and myometrial SNR were also calculated. Intraclass correlation coefficients were used to analyse the consistency of the measurement results by 2 observers. Analysis of variance test or Friedman rank sum test was used to compare the differences in subjective scores, SNR, and CNR under different AFs/different degrees of fat suppression. RESULTS: Images by AFs of CS3, CS4, and CS5 had the highest SNR and CNR. Among them, CS5 had the shortest scan time. CS5 also had one of the highest subjective scores. There was no significant difference in SNR and CNR among images acquired with different degrees of fat suppression. Also, images with moderate fat suppression had the highest subjective scores. CONCLUSION: The CS5 combined with moderate fat suppression is recommended for routine female pelvic 3D-ISO-T2WI scan. ADVANCES IN KNOWLEDGE: The CS5 has the highest image quality and has the shortest scan time, which is the best AF. Moderate fat suppression has the highest subjective scores. The CS5 and moderate fat suppression are the best combination for a female pelvic 3D-ISO-T2WI scan.
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Imageamento Tridimensional , Imageamento por Ressonância Magnética , Útero , Humanos , Feminino , Útero/diagnóstico por imagem , Adulto , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Pessoa de Meia-Idade , Adulto Jovem , Razão Sinal-RuídoRESUMO
Sandstone is a common construction material widely distributed in mountain tunnels. Its stability determines the safety and service life of tunnel projects. The surrounding rock of the tunnel is subject to frequent fire incidents and long-term erosion by acidic groundwater throughout its entire life cycle. This study investigated the pore characteristics and mechanical properties of sandstone under different high temperatures and acidic solutions. The T2 spectrum distribution, pore size distribution, porosity, compressive strength, and elastic modulus of sandstone were observed through uniaxial compression tests and nuclear magnetic resonance (NMR) tests. The results showed that high temperature and acidic solutions significantly affected the T2 spectrum distribution, pore size distribution, porosity, compressive strength, and elastic modulus of sandstones, and their effects on the pore structure and mechanical properties of sandstone differed in each stage. The effect of high temperature on the pore structure and mechanical properties of sandstone was stronger than that of the acidic solutions. In addition, the mechanism of damage formation is characterized by the porosity variation of sandstone. The pore structure of sandstone showed a close linear relationship with mechanical properties, indicating that changes in microstructure inevitably affected the macroscopic mechanical properties of sandstone. These findings can guide the construction and repair of rock failure induced by fire and acidic groundwater, providing a reference for associated tunnel projects.
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Temperatura Alta , Temperatura , Módulo de ElasticidadeRESUMO
OBJECTIVE: This study aims to explore the diagnostic performance of amide proton transfer (APT) imaging combined with diffusion kurtosis imaging (DKI) in differentiating stage Ia endometrial carcinoma (EC) and endometrial polyps (EP). METHODS: All patients were scanned with APT and DKI sequences with 3.0 T MRI before surgery. The MRI data of 32 patients with histopathologically confirmed stage Ia EC and 17 patients with EP were retrospectively analyzed. Amide proton transfer, mean kurtosis (MK) and mean diffusivity (MD) values were measured. ROC curves were employed to evaluate the efficiency of differentiating and diagnosing stage Ia EC and EP, followed by the Delong test to compare the differences between the areas under the curve (AUCs) of each parameter. Additionally, the Pearson correlation analysis was performed to assess the correlation between APT values and MK and MD. RESULTS: The measured APT, MK, and MD values of the patients with stage Ia EC were 2.609 ± 0.504%,0.641 ± 0.113 and 0.904(0.816, 1.108) µm2/ms, while those of patients with EP were1.909 ± 0.418%, 0.495 ± 0.069, and 1.650 (1.458, 1.815) µm2/ms. The AUCs of APT, MK, MD, MK + MD, and APT + MK + MD in differentiating stage Ia EC and EP were.850, 0.879, 0.893, 0.930 and 0.976, respectively. The AUCs of APT + MK + MD were significantly higher than the AUCs of APT or MK (P < 0.05). The APT value was weakly and positively correlated with the MK value (r = 0.299, P = 0.037), while the APT value was moderately and negatively correlated with the MD value (r = -0.520, P < 0.001). CONCLUSION: Both APT and DKI effectively differentiated stage Ia EC and EP; however, when combined, APT and DKI improved the ability to differentiate these diseases, boosting the value of using a combination of these modalities in clinical applications.
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Neoplasias do Endométrio , Prótons , Feminino , Humanos , Estudos Retrospectivos , Imagem de Tensor de Difusão/métodos , Imagem de Difusão por Ressonância Magnética/métodosRESUMO
PURPOSE: To explore the value of Diffusion kurtosis imaging (DKI) with multiple quantitative parameters in predicting microsatellite instability (MSI) status in endometrial carcinoma (EC). METHODS: Data of 38 patients with EC were retrospectively analyzed, including 12 MSI and 26 microsatellite stability (MSS). All patients underwent preoperative 1.5T MR examination. The quantitative values of the DKI sequence in the tumor parenchyma of the two groups, including mean kurtosis (MK), axial kurtosis (Ka), radial kurtosis (Kr), fractional anisotropy (FA), fractional anisotropy of kurtosis (FAk), mean diffusivity (MD), axial diffusivity (Da), and radial diffusivity (Dr) were measured by two observers, respectively. RESULTS: The MK, Ka, Kr, FA, FAk, MD, Da, and Dr values of the MSI group were 1.074 ± 0.162, 1.253 ± 0.229, 0.886 ± 0.205, 0.207 ± 0.041, 0.397 ± 0.129, 0.890 ± 0.158 µm2/ms, 1.083 ± 0.218 µm2/ms, and 0.793 ± 0.133 µm2/ms, and 0.956 (0.889,1.002), 1.048 ± 0.211, 0.831 ± 0.099, 0.188 ± 0.061, 0.334 (0.241,0.410), 1.043 ± 0.217 µm2/ms, 1.235 ± 0.229 µm2/ms, and 0.946 ± 0.215 µm2/ms in the MSS group. The MK and Ka values of the MSI group were higher than those of the MSS group (P<0.05), while the MD and Dr values were lower than those of the MSS group (P<0.05). The AUC of MK, Ka, MD, and Dr values in predicting MSI status of EC was 0.763, 0.729, 0.731, 0.748, respectively. The sensitivity was 58.3%, 50.0%, 65.4%, 61.5%, and the specificity was 96.2%, 92.3%, 75.0%, 83.3%, respectively. CONCLUSION: DKI can provide multiple quantitative parameters for predicting the MSI status of EC, and assist gynecologist to optimize the treatment plan for the patients.
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Neoplasias do Endométrio , Instabilidade de Microssatélites , Feminino , Humanos , Estudos Retrospectivos , Imagem de Tensor de Difusão/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/genéticaRESUMO
PURPOSE: To assess the value of multimodal MRI, including amide proton transfer-weighted imaging (APT), diffusion kurtosis imaging (DKI), and T2 mapping sequences for estimating human epidermal growth factor receptor-2 (Her-2) expression in patients with endometrial cancer (EC). METHODS: A total of 54 patients with EC who underwent multimodal pelvic MRI followed by biopsy were retrospectively selected and divided into the Her-2 positive (n = 24) and Her-2 negative (n = 30) groups. Her-2 expression was confirmed by immunohistochemistry (IHC). Two observers measured APT, mean kurtosis (MK), mean diffusivity (MD), and T2 values for EC lesions. RESULTS: The Her-2 (+) group showed higher APT values and lower MD and T2 values than the Her-2 (-) group (all p < 0.05); there was no significant difference in MK values (p > 0.05). The area under the receiver operating characteristic curve (AUC) of APT, MD, T2, APT + T2, APT + MD, T2 + MD, and APT + MD + T2 models to identify the two groups of cases were 0.824, 0.695, 0.721, 0.824, 0.858, 0.782, and 0.860, respectively, and the diagnostic efficacy after combined APT + MD + T2 value was significantly higher than those of MD and T2 values individually (p = 0.018, 0.028); the diagnostic efficacy of the combination of APT + T2 values was significantly higher than that of T2 values separately (p = 0.028). Weak negative correlations were observed between APT and T2 values (r = -0.365, p = 0.007), moderate negative correlations between APT and MD values (r = -0.560, p < 0.001), and weak positive correlations between MD and T2 values (r = 0.336, p = 0.013). The APT values were independent predictors for assessing Her-2 expression in EC patients. CONCLUSION: The APT, DKI, and T2 mapping sequences can be used to preoperatively assess the Her-2 expression in EC, which can contribute to more precise treatment for clinical preoperative.
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PURPOSE: To assess the value of amide proton transfer weighted (APTw) combined with intra-voxel incoherent motion (IVIM) imaging in differential diagnosis of stage I-II endometrial carcinoma (EC) and endometrial polyp (EP). METHODS: A total of 53 female patients (37 cases with EC and 16 cases with EP) confirmed by surgical resection or biopsy from June 2019 to Jan. 2022 were retrospectively reviewed. All patients underwent 3.0 T magnetic resonance imaging (MRI) examination including diffusion weighted imaging (DWI), APTw and IVIM scans. The pure diffusion coefficient (D), pseudo-diffusion coefficient (Dâ), perfusion fraction (f), apparent diffusion coefficient (ADC) and APT values were independently measured by two observers. Intra-class correlation coefficients (ICC) were used to test the consistency of measurements by the two observers. Mann-Whitney U test was performed to analyze the difference of each parameter between EC and EP groups. Receiver operator characteristic (ROC) analysis was performed, and the Delong test was used for ROC curve comparison. Pearson's correlation analysis was used to assess the correlation between APTw and IVIM parameters. RESULTS: There was no significant difference in clinical manifestations between the two groups (P > 0.05). APT and Dâ values of the EC group were significantly higher than those of the EP group [APT: 2.64 ± 0.50% vs. 2.05 ± 0.58%; and Dâ: (54.06 ± 36.06) × 10-3 mm2/s vs. (30.54 ± 16.67) × 10-3 mm2/s]. D, f and ADC values of EC group were significantly lower than those of EP group [D: 0.62(0.53,0.76) × 10-3 mm2/s vs. (1.45 ± 0.48) × 10-3 mm2/s; f: 22.18 ± 8.08% vs. 30.80 ± 8.92%; and ADC: (0.88 ± 0.16) × 10-3 mm2/s vs. (1.57 ± 0.43) × 10-3 mm2/s]. The area under ROC curves were observed as: AUC (IVIM+APT) > AUC (D) > AUC (ADC) > AUC (APT) > AUC (f) > AUC (Dâ). Delong test suggested statistical significance between AUC by APT and D, D and Dâ, D and f, Dâ and ADC, APT and com(IVIM+APT), Dâ and com(IVIM+APT), as well as f and com(IVIM+APT). No significant correlation between the APT and IVIM parameters was observed in either EC or EP group. CONCLUSION: Both APT and IVIM parameters showed statistical differences between EC and EP. With combination of APT and IVIM parameters, the diagnostic accuracy between EC and EP can be significantly improved.
Assuntos
Neoplasias do Endométrio , Prótons , Humanos , Feminino , Estudos Retrospectivos , Amidas , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Endométrio/diagnóstico por imagem , Movimento (Física)RESUMO
Background: To investigate the value of amide proton transfer weighted (APTw) imaging combined with modified Dixon fat quantification (mDixon-Quant) imaging in determining the degree of differentiation of cervical squamous carcinoma (CSC) against histopathologic. Methods: Magnetic resonance imaging (MRI) data were collected from 52 CSC patients. According to histopathologic results, patients were divided into the poorly differentiated group (37 cases) and the well/moderately differentiated group (15 cases). The APTw value by APTw imaging and the fat fraction (FF) and transverse relaxation rate R 2 * values by mDixon-Quant were independently measured by two radiologists. Intra-class correlation coefficients (ICCs) were used to test the consistency of APTw, FF, and R 2 * values measured by the two observers. The Mann-Whitney U test was used to analyze the difference in each parameter between the two groups. Logistic regression analysis was used to assess the association between the degree of differentiation on histopathology and imaging parameters by APTw and mDixon Quant. The ROC curve was used to evaluate the diagnostic efficacy of various parameters and their combination in distinguishing the degree of CSC differentiation on histopathology. The DeLong test was used to access the differences among the area under the ROC curves (AUCs). The Pearson correlation coefficient was used to evaluate the correlation between APTw and mDixon-Quant imaging parameters. Results: The APTw means were 2.95 ± 0.78% and 2.05 (1.85, 2.65)% in the poorly and well/moderately differentiated groups, respectively. The R 2 * values were 26.62 (21.99, 33.31)/s and 22.93 ± 6.09/s in the poorly and well/moderately differentiated groups, respectively (P < 0.05). The AUCs of APTw, R 2 * , and their combination were 0.762, 0.686, and 0.843, respectively. The Delong test suggested statistical significance between R 2 * and the combination of APTw and R 2 * . R 2 * values showed a significant correlation with APTw values in the poorly differentiated group. Conclusions: APTw combined with mDixon-Quant can be used to efficiently distinguish the differention degrees of CSC diagnosed on histopathology.
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Purpose: To develop and validate multi-parametric MRI (MP-MRI)-based radiomics models for the prediction of biological characteristics in endometrial cancer (EC). Methods: A total of 292 patients with EC were divided into LVSI (n = 208), DMI (n = 292), MSI (n = 95), and Her-2 (n = 198) subsets. Total 2316 radiomics features were extracted from MP-MRI (T2WI, DWI, and ADC) images, and clinical factors (age, FIGO stage, differentiation degree, pathological type, menopausal state, and irregular vaginal bleeding) were included. Intra-class correlation coefficient (ICC), spearman's rank correlation test, univariate logistic regression, and least absolute shrinkage and selection operator (LASSO) were used to select radiomics features; univariate and multivariate logistic regression were used to identify clinical independent risk factors. Five classifiers were applied (logistic regression, random forest, decision tree, K-nearest neighbor, and Bayes) to construct radiomics models for predicting biological characteristics. The clinical model was built based on the clinical independent risk factors. The combined model incorporating the radiomics score (radscore) and the clinical independent risk factors was constructed. The model was evaluated by ROC curve, calibration curve (H-L test), and decision curve analysis (DCA). Results: In the training cohort, the RF radiomics model performed best among the five classifiers for the three subsets (MSI, LVSI, and DMI) according to AUC values (AUCMSI: 0.844; AUCLVSI: 0.952; AUCDMI: 0.840) except for Her-2 subset (Decision tree: AUC=0.714), and the combined model had higher AUC than the clinical model in each subset (MSI: AUCcombined =0.907, AUCclinical =0.755; LVSI: AUCcombined =0.959, AUCclinical =0.835; DMI: AUCcombined = 0.883, AUCclinical =0.796; Her-2: AUCcombined =0.812, AUCclinical =0.717; all P<0.05). Nevertheless, in the validation cohort, significant differences between the two models (combined vs. clinical model) were found only in the DMI and LVSI subsets (DMI: AUCcombined =0.803, AUCclinical =0.698; LVSI: AUCcombined =0.926, AUCclinical =0.796; all P<0.05). Conclusion: The radiomics analysis based on MP-MRI and clinical independent risk factors can potentially predict multiple biological features of EC, including DMI, LVSI, MSI, and Her-2, and provide valuable guidance for clinical decision-making.