Ultrasound study of right ventricular myocardial perfusion and functional changes in hypertrophic cardiomyopathy.

BACKGROUND: To evaluate the changes of right ventricular (RV) myocardial perfusion and function in patients with hypertrophic cardiomyopathy (HCM) by myocardial contrast echocardiography (MCE) and speckle tracking (2D-STE), and to explore the relationship between RV myocardial perfusion and strain. METHODS: Conventional ultrasound, MCE and 2D-STE were performed on 29 HCM patients and 21 healthy subjects to analyze RV myocardial perfusion, RV global strain, RV free wall strain, and strain of each segment. The correlation between RV myocardial perfusion and strain was further analyzed in HCM patients. RESULTS: MCE results showed that the regional myocardial perfusion of the RV in HCM patients was decreased. Compared with the normal control group, the mean slope (ß) in the middle and apical segments of the RV free wall, and the peak intensity (A), ß, myocardial blood flow (MBF) of the ventricular septum decreased in HCM patients (P < 0.05). RV function was impaired in HCM patients. The RV global strain (RV GLS), and the strain of RV free wall and each segment were lower than those in the normal control group (P < 0.05). Correlation analysis showed that there was a certain correlation between RV myocardial perfusion and strain, such as the ß of the whole RV in HCM group had a positive correlation with the strain of the middle segment of the interventricular septum (r = 0.550, P = 0.002). CONCLUSIONS: The regional myocardial perfusion and strain of the RV in HCM patients are reduced, and there is a positive correlation between them, suggesting that the reduction of myocardial strain may be related to the impairment of myocardial microcirculation.

Differences in the microcirculation disturbance in the right and left ventricles of neonatal rats with hypoxic pulmonary hypertension.

Microcirculation disturbance is a crucial pathological basis of heart damage; however, microcirculation alterations induced by hypoxic pulmonary hypertension (HPH) remain unknown, and the left ventricle (LV) in HPH is conventionally ignored. Herein, we investigated the changes in the cardiac structure, function and microcirculation after HPH and further compared the differences between the right ventricle (RV) and LV. Using a neonatal rat model of HPH, we found RV myocardial hypertrophy, dysfunction and poor myocardial perfusion in HPH rats. Additionally, RV microcirculation disturbance manifested as the abnormal expression of endothelin-1/eNOS and increased expression of intercellular cell adhesion molecule-1 (ICAM-1) or E-selectin 3 days after hypoxia, followed by vascular inflammation, coronary arterial remodeling and microvascular sparseness. Impairment in LV vasodilation was detected in rats after 3 days of hypoxia; however, no obvious microvascular rarefaction or inflammatory reaction was observed in the LV. In conclusion, our results suggest that HPH mainly triggers RV microcirculation disturbances, causing low myocardial perfusion damage and cardiac dysfunction. Despite the differences in the RV and LV, their impaired microvascular function, mediated by endothelial cells, occurs almost simultaneously after HPH, earlier than cardiac functional or structural abnormalities.

Relationship Between Myocardial Perfusion and Myocardial Function in Dilated Cardiomyopathy by Shown Ultrasonography.

Myocardial contrast echocardiography (MCE) and two-dimensional speckle tracking echocardiography (2D-STE) were used to detect left ventricular myocardial microcirculation perfusion and myocardial systolic function in dilated cardiomyopathy (DCM) and to explore the relationship between the two.Conventional ultrasound, MCE, and 2D-STE examinations were performed on 30 patients and 30 controls. Left ventricular microcirculation perfusion, left ventricular longitudinal strain (GLS), and circumferential strain (GCS) were analyzed to further compare the correlation between left ventricular perfusion and myocardial strain parameters.Regional myocardial perfusion was reduced in patients with DCM, manifesting as a decrease in the rising slope (A) of the mid-segment of the posterior septum, the peak intensity (PI) of the mid-segment of the anterior septum and the posterior septum, the apical segment of the lateral wall, the area under the curve (AUC) of the posterior septum, the basal segment of the posterior wall, the anterior septum, posterior septum, posterior wall, mid-segment of the lateral wall, and apical segment of the lateral wall and the overall average PI and AUC of the mid-segment, compared with that in the controls (P < 0.05). The left ventricular systolic function and the strain parameters GLS and GCS of DCM patients were lower than those of the controls (P < 0.001). Correlation analysis revealed a positive correlation between the A of the mitral valve and GCS (r = 0.372, P = 0.043), and MV-E/e' had a positive correlation with the AUC of the basal and intermediate segments (r = 0.379, P = 0.039; r = 0.404, P = 0.027).In patients with DCM, regional myocardial microcirculation perfusion is reduced, and myocardial strain is impaired. Myocardial perfusion has a good positive correlation with myocardial mechanics.

Cultivar Discrimination of Single Alfalfa (Medicago sativa L.) Seed via Multispectral Imaging Combined with Multivariate Analysis.

Rapid and accurate discrimination of alfalfa cultivars is crucial for producers, consumers, and market regulators. However, the conventional routine of alfalfa cultivars discrimination is time-consuming and labor-intensive. In this study, the potential of a new method was evaluated that used multispectral imaging combined with object-wise multivariate image analysis to distinguish alfalfa cultivars with a single seed. Three multivariate analysis methods including principal component analysis (PCA), linear discrimination analysis (LDA), and support vector machines (SVM) were applied to distinguish seeds of 12 alfalfa cultivars based on their morphological and spectral traits. The results showed that the combination of morphological features and spectral data could provide an exceedingly concise process to classify alfalfa seeds of different cultivars with multivariate analysis, while it failed to make the classification with only seed morphological features. Seed classification accuracy of the testing sets was 91.53% for LDA, and 93.47% for SVM. Thus, multispectral imaging combined with multivariate analysis could provide a simple, robust and nondestructive method to distinguish alfalfa seed cultivars.

Construction and Evaluation of a Predictive Model for Grassroots Nurses' Risk Perception of "Internet + Nursing Services": A Multicenter Cross-Sectional Study.

Purpose: The development of "Internet + nursing services" can effectively solve the problem of population aging, and grassroots nurses are the primary providers of such services in rural areas. This study aimed to analyze the factors affecting grassroots nurses' risk perception of "Internet + nursing services" and construct a predictive model. Patients and Methods: A multicenter cross-sectional study of 2220 nurses from 27 secondary hospitals and 36 community health centers in Hubei Province was conducted from August to December 2023 using a multi-stage cluster sampling method. Information was collected through a structured anonymous questionnaire. A Chi-square test, a Welch t-test, and binary logistic regression analyses were employed to determine independent risk factors for grassroots nurses' risk perception of "Internet + nursing services", and a nomogram was constructed. Receiver operating characteristic curves, calibration curves, and decision curves were plotted to evaluate the discrimination, calibration, and clinical effectiveness of the nomogram. Results: A total of 2050 valid questionnaires were collected, demonstrating that 51.95% of grassroots nurses thought that "Internet + nursing services" was a medium-high risk. Age, other sources of income, knowledge about "Internet + nursing services", personal safety, physical function, occupational exposure, social psychosocial, and time risk (P<0.05) were independent risk factors for grassroots nurses' risk perception. The area under the receiver operating characteristic curve of the nomogram was 0.939. The calibration and decision curve analyses demonstrated good calibration ability and clinical application values. Conclusion: The prediction model constructed in this study has good prediction ability. Most grassroots nurses believe that "Internet + nursing services" are risky and influenced by several factors. It is suggested that the government and hospitals should formulate a unified charging standard, improve the safety guarantee, and gradually eliminate the concerns of grassroots nurses.

Predicting the Ki-67 proliferation index in cervical cancer: a preliminary comparative study of four non-Gaussian diffusion-weighted imaging models combined with histogram analysis.

Background: The prognosis for patients with cervical cancer (CC) is strongly correlated with the Ki-67 proliferation index (PI). However, the Ki-67 PI obtained through biopsy has certain limitations. The non-Gaussian distribution diffusion model of magnetic resonance imaging (MRI) may play an important role in characterizing tissue heterogeneity. At present, there are limited data available concerning the prediction of Ki-67 PI using models based on histogram features of non-Gaussian diffusion distribution. This study aimed to determine whether preoperative histogram features from multiple non-Gaussian models of diffusion-weighted imaging can predict the Ki-67 PI in patients with CC. Methods: Our cross-sectional prospective study recruited a total of 53 patients suspected of having CC who underwent 3.0-T MRI at Sun Yat-sen Memorial Hospital of Sun Yat-sen University between January 2022 and January 2023. Fifteen b values (0-4,000 s/mm2) were used for diffusion-weighted imaging. A total of nine parameters from four non-Gaussian diffusion-weighted imaging models, including continuous-time random walk (CTRW), diffusion kurtosis imaging (DKI), fractional order calculus (FROC), and intravoxel incoherent motion (IVIM), were used. Whole-tumor volumetric histogram analysis of these parameters was then obtained. In logistic regression, significant histogram characteristics were statistically examined across two groups to build the final prediction model. To assess diagnostic parameters of the proposed model in the diagnosis of the Ki-67 PI, along with the sensitivity, specificity, and diagnostic accuracy of these various parameters from the four models, receiver operating feature analysis was applied. Results: Among the 53 patients (55.3±9.6 years, ranging from 23 to 79 years) included in the study, 15 had a Ki-67 PI ≤50% and 38 had a Ki-67 PI >50%. Univariable analysis determined that 12 histogram features were statistically different between the two groups. In multivariable logistic regression, we ultimately selected 6 histogram features to construct the final prediction model, with CTRW_α_10th percentile [odds ratio (OR) =0.955; 95% confidence interval (CI): 0.92-0.99; P=0.019], CTRW_α_robust mean absolute deviation (OR =0.893; 95% CI: 0.81-0.99; P=0.028), and CTRW_α_uniformity (OR =0.000, 95% CI: 0.00-0.90, P=0.047) being the independent predictive variables. The area under the curve of the combined prediction model was 0.845 (95% CI: 0.74-0.95), with a sensitivity of 78.9% (95% CI: 0.63-0.90), a specificity of 86.7% (95% CI: 0.60-0.98), an accuracy of 81.1% (95% CI: 0.68-0.91), a positive predictive value of 93.8% (95% CI: 0.79-0.99), and a negative predictive value of 61.9% (95% CI: 0.38-0.82). Conclusions: The histogram features of multiple non-Gaussian diffusion-weighted imaging can help to predict the Ki-67 PI of CC, providing a new method for the noninvasive evaluation of critical biological features of CC.

Whole-tumor histogram analysis of multiple non-Gaussian diffusion models at high b values for assessing cervical cancer.

PURPOSE: To assess the diagnostic potential of whole-tumor histogram analysis of multiple non-Gaussian diffusion models for differentiating cervical cancer (CC) aggressive status regarding of pathological types, differentiation degree, stage, and p16 expression. METHODS: Patients were enrolled in this prospective single-center study from March 2022 to July 2023. Diffusion-weighted images (DWI) were obtained including 15 b-values (0 ~ 4000 s/mm2). Diffusion parameters derived from four non-Gaussian diffusion models including continuous-time random-walk (CTRW), diffusion-kurtosis imaging (DKI), fractional order calculus (FROC), and intravoxel incoherent motion (IVIM) were calculated, and their histogram features were analyzed. To select the most significant features and establish predictive models, univariate analysis and multivariate logistic regression were performed. Finally, we evaluated the diagnostic performance of our models by using receiver operating characteristic (ROC) analyses. RESULTS: 89 women (mean age, 55 ± 11 years) with CC were enrolled in our study. The combined model, which incorporated the CTRW, DKI, FROC, and IVIM diffusion models, offered a significantly higher AUC than that from any individual models (0.836 vs. 0.664, 0.642, 0.651, 0.649, respectively; p < 0.05) in distinguishing cervical squamous cell cancer from cervical adenocarcinoma. To distinguish tumor differentiation degree, except the combined model showed a better predictive performance compared to the DKI model (AUC, 0.839 vs. 0.697, respectively; p < 0.05), no significant differences in AUCs were found among other individual models and combined model. To predict the International Federation of Gynecology and Obstetrics (FIGO) stage, only DKI and FROC model were established and there was no significant difference in predictive performance among different models. In terms of predicting p16 expression, the predictive ability of DKI model is significantly lower than that of FROC and combined model (AUC, 0.693 vs. 0.850, 0.859, respectively; p < 0.05). CONCLUSION: Multiple non-Gaussian diffusion models with whole-tumor histogram analysis show great promise to assess the aggressive status of CC.

CT and MRI features of sarcomatoid urothelial carcinoma of the bladder and its differential diagnosis with conventional urothelial carcinoma.

BACKGROUND: Sarcomatoid urothelial carcinoma (SUC) is a rare and highly malignant form of bladder cancer with a poor prognosis. Currently, there is limited information on the imaging features of bladder SUC and reliable indicators for distinguishing it from conventional urothelial carcinoma (CUC). The objective of our study was to identify the unique imaging characteristics of bladder SUC and determine factors that aid in its differential diagnosis. MATERIALS AND METHODS: This retrospective study enrolled 22 participants with bladder SUC and 61 participants with CUC. The clinical, pathologic, and CT/MRI data from both groups were recorded, and a comparison was conducted using univariate analysis and multinomial logistic regression for distinguishing SUC from CUC. RESULTS: The majority of SUCs were located in the trigone of the bladder and exhibited large tumor size, irregular shape, low ADC values, Vesical Imaging-Reporting and Data System (VI-RADS) score ≥ 4, the presence of necrosis, and an invasive nature. Univariate analysis revealed significant differences in terms of tumor location, shape, the maximum long-axis diameter (LAD), the short-axis diameter (SAD), ADC-value, VI-RADS scores, necrosis, extravesical extension (EVE), pelvic peritoneal spread (PPS), and hydronephrosis/ureteral effusion (p < .001 ~ p = .037) between SUCs and CUCs. Multinomial logistic regression found that only SAD (p = .014) and necrosis (p = .003) emerged as independent predictors for differentiating between SUC and CUC. The model based on these two factors achieved an area under curve (AUC) of 0.849 in ROC curve analysis. CONCLUSION: Bladder SUC demonstrates several distinct imaging features, including a high incidence of trigone involvement, large tumor size, and obvious invasiveness accompanied by necrosis. A bladder tumor with a large SAD and evidence of necrosis is more likely to be SUC rather than CUC.

MRI-based deep learning and radiomics for prediction of occult cervical lymph node metastasis and prognosis in early-stage oral and oropharyngeal squamous cell carcinoma: a diagnostic study.

INTRODUCTION: The incidence of occult cervical lymph node metastases (OCLNM) is reported to be 20-30% in early-stage oral cancer and oropharyngeal cancer. There is a lack of an accurate diagnostic method to predict occult lymph node metastasis and to help surgeons make precise treatment decisions. AIM: To construct and evaluate a preoperative diagnostic method to predict OCLNM in early-stage oral and oropharyngeal squamous cell carcinoma (OC and OP SCC) based on deep learning features (DLFs) and radiomics features. METHODS: A total of 319 patients diagnosed with early-stage OC or OP SCC were retrospectively enrolled and divided into training, test and external validation sets. Traditional radiomics features and DLFs were extracted from their MRI images. The least absolute shrinkage and selection operator (LASSO) analysis was employed to identify the most valuable features. Prediction models for OCLNM were developed using radiomics features and DLFs. The effectiveness of the models and their clinical applicability were evaluated using the area under the curve (AUC), decision curve analysis (DCA), and survival analysis. RESULTS: Seventeen prediction models were constructed. The Resnet50 deep learning (DL) model based on the combination of radiomics and DL features achieves the optimal performance, with AUC values of 0.928 (95% CI: 0.881-0.975), 0.878 (95% CI: 0.766-0.990), 0.796 (95% CI: 0.666-0.927), and 0.834 (95% CI: 0.721-0.947) in the training, test, external validation set1, and external validation set2, respectively. Moreover, the Resnet50 model has great prediction value of prognosis in patients with early-stage OC and OP SCC. CONCLUSION: The proposed MRI-based Resnet50 DL model demonstrated high capability in diagnosis of OCLNM and prognosis prediction in the early-stage OC and OP SCC. The Resnet50 model could help refine the clinical diagnosis and treatment of the early-stage OC and OP SCC.

Comparison of image quality and quantitative parameters in intravoxel incoherent motion imaging at 3-T based on turbo spin-echo and echo-planar imaging in patients with oral cancer.

PURPOSE: To compare the image quality, apparent diffusion coefficient (ADC), and intravoxel incoherent motion- (IVIM) derived parameters of IVIM imaging based on turbo spin-echo (TSE) and echo-planar imaging (EPI) of patients with oral cancer and to assess the equivalence of the ADC and IVIM-derived parameters. METHODS: Thirty patients with oral cancer underwent TSE-IVIM and EPI-IVIM imaging using a 3.0-T system. The distortion ratio (DR), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), qualitative evaluations of image quality, ADC, pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were compared between the two sequences. The consistency of the quantitative parameters in oral cancer between the TSE and EPI sequences was evaluated using a Bland-Altman analysis. RESULTS: TSE-IVIM had a significantly smaller DR than EPI-IVIM (P < 0.001). The CNR of EPI-IVIM on most of the anatomical sites was significantly higher than that of TSE-IVIM (P < 0.05), while the SNR was not significantly different (P > 0.05). TSE-IVIM had significantly higher image quality, less distortion and artifacts, and lower image contrast compared with EPI-IVIM (P < 0.05). The lesion-edge sharpness and diagnostic confidence of EPI-IVIM were lower than that of TSE-IVIM, although no significant differences existed (P > 0.05). The ADC and D of TSE-IVIM had better reproducibility (intraclass correlation coefficient > 0.9). Although no significant difference existed for the ADC and IVIM-derived parameters of lesions between the two sequences (P > 0.05), wide limits of agreement were found in the Bland-Altman plots. CONCLUSION: TSE-IVIM could be used as an alternative technique to EPI-IVIM for patients with oral cancer because of its better image quality. Furthermore, TSE-IVIM can provide more accurate quantitative parameters. However, the quantitative parameters derived from the two IVIM techniques cannot be used as equivalent parameters for patients with oral cancer.

Screening of the best time window for MSC transplantation to treat acute myocardial infarction with SDF-1α antibody-loaded targeted ultrasonic microbubbles: An in vivo study in miniswine.

The present study aimed to screen the best time window for the transplantation of bone marrow mesenchymal stem cells (MSCs) after acute myocardial infarction (MI) through targeted ultrasound microbubbles loaded with SDF-1α antibody. Thirty-six MI miniswine were randomly divided into six experimental groups according to the duration after infarction (1 day, 3 days, 1 week, 2 weeks, 3 weeks, and 4 weeks after infarction). MSCs were labeled with BrdU and then injected through the coronary artery in the stem cell transplantation group to detect the number of transplanted MSCs at different time points after MI. Three miniswine were randomly selected as the control group (sham operation: open chest without ligation of the coronary artery). All SDF-1α groups and control groups were injected with a targeted microbubble ultrasound contrast agent. The values of the myocardial perfusion parameters (A, ß, and A × ß) were determined. A T, ß T, and (A × ß)T varied with time and peaked 1 week after MI (P < 0.05). The number of transplanted stem cells in the myocardium through coronary injection of MSCs at 1 week was the greatest and consistent with the changing tendency of A T, ß T, and (A × ß)T (r = 0.658, 0.778, 0.777, P < 0.05). ß T(X), (A × ß)T(X), and the number of transplanted stem cells was used to establish the regression equation as follows: Y = 36.11 + 17.601X; Y = 50.023 + 3.348X (R 2 = 0.605, 0.604, P < 0.05). The best time window for transplanting stem cells was 1 week after MI. The myocardial perfusion parameters of the SDF-1α targeted contrast agent can be used to predict the number of transplanted stem cells in the myocardial tissue.

Improving visualization of free fibula flap perforators and reducing radiation dose in dual-energy CT angiography.

Background: The precise assessment of the perforators of the fibula free flap (FFF) is crucial for minimizing procedure-related complications when harvesting the FFF in patients with maxillofacial lesions. This study aims to investigate the utility of virtual noncontrast (VNC) images for radiation dose saving and to determine the optimal energy level of virtual monoenergetic imaging (VMI) reconstructions in dual-energy computed tomography (DECT) for visualization of the perforators of the fibula free flap (FFF). Methods: Data from 40 patients with maxillofacial lesions who received lower extremity DECT examinations in the noncontrast and arterial phase were collected in this retrospective, cross-sectional study. To compare VNC images from the arterial phase with true non-contrast images in a DECT protocol (M_0.5-TNC) and to compare VMI images with 0.5 linear images blending from the arterial phase (M_0.5-C), the attenuation, noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and subjective image quality were assessed in different arteries, muscles, and fat tissues. Two readers evaluated the image quality and visualization of the perforators. The dose-length product (DLP) and CT volume dose index (CTDIvol) were used to determine the radiation dose. Results: Objective and subjective analyses showed no significant difference between the M_0.5-TNC and VNC images in the arteries and muscles (P>0.09 to P>0.99), and VNC imaging could reduce 50% of the radiation dose (P<0.001). Compared with those of the M_0.5-C images, the attenuation and CNR of VMI reconstructions at 40 kiloelectron volt (keV) and 60 keV were higher (P<0.001 to P=0.04). Noise was similar at 60 keV (all P>0.99) and increased at 40 keV (all P<0.001), and the SNR in arteries was increased at 60 keV (P<0.001 to P=0.02) in VMI reconstructions compared with those in the M_0.5-C images. The subjective scores in VMI reconstructions at 40 and 60 keV was higher than those in M_0.5-C images (all P<0.001). The image quality at 60 keV was superior to that at 40 keV (P<0.001), and there was no difference in the visualization of the perforators between 40 and 60 keV (P=0.31). Conclusions: VNC imaging is a reliable technique for replacing M_0.5-TNC and provides radiation dose saving. The image quality of the 40-keV and 60-keV VMI reconstructions was higher than that of the M_0.5-C images, and 60 keV provided the best assessment of perforators in the tibia.

Improving the Visualization of the Adrenal Veins Using Virtual Monoenergetic Images from Dual-Energy Computed Tomography before Adrenal Venous Sampling.

(1) Background: This study explored the optimal energy level in advanced virtual monoenergetic images (VMI+) from dual-energy computed tomography angiography (DE-CTA) for adrenal veins visualization before adrenal venous sampling (AVS). (2) Methods: Thirty-nine patients were included in this prospective single-center study. The CT value, noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured in both adrenal veins and abdominal solid organs and were then compared between VMI+ within the range of 40-80 kiloelectron volt (keV). The visualization rate of the adrenal veins and the overall image quality of solid organs were subjectively compared among different keV VMI+. The AVS success rate was recorded for 20 patients. (3) Results: For the adrenal veins, 40 keV VMI+ had the peak CT value, noise and CNR (p < 0.05). Subjectively, the visualization rate was the highest at 40 keV (100% for the right adrenal vein, and 97.4% for the left adrenal vein) (p < 0.05). For solid organs, the CT value, noise and CNR at 50 keV were lower than those at 40 keV (p < 0.05), but the SNR was similar between 40 keV and 50 keV. The overall subjective image quality of solid organs at 50 keV was the best (p < 0.05). The AVS success rate was 95%. (4) Conclusions: For VMI+, 40 keV was the preferential energy level to obtain a high visualization rate of the adrenal veins and a high success rate of AVS, while 50 keV was the favorable energy level for the depiction of abdominal organs.

Evaluation of Quantitative Dual-Energy Computed Tomography Parameters for Differentiation of Parotid Gland Tumors.

RATIONALE AND OBJECTIVES: To assess the diagnostic performance of quantitative parameters from dual-energy CT (DECT) in differentiating parotid gland tumors (PGTs). MATERIALS AND METHODS: 101 patients with 108 pathologically proved PGTs were enrolled and classified into four groups: pleomorphic adenomas (PAs), warthin tumors (WTs), other benign tumors (OBTs), and malignant tumors (MTs). Conventional CT attenuation and DECT quantitative parameters, including iodine concentration (IC), normalized iodine concentration (NIC), effective atomic number (Zeff), electron density (Rho), double energy index (DEI), and the slope of the spectral Hounsfield unit curve (λHU), were obtained and compared between benign tumors (BTs) and MTs, and further compared among the four subgroups. Logistic regression analysis was used to assess the independent parameters and the receiver operating characteristic (ROC) curves were used to analyze the diagnostic performance. RESULTS: Attenuation, Zeff, DEI, IC, NIC, and λHU in the arterial phase (AP) and venous phase (VP) were higher in MTs than in BTs (p < 0.001-0.047). λHU in VP and Zeff in AP were independent predictors with an area under the curve (AUC) of 0.84 after the combination. Furthermore, attenuation, Zeff, DEI, IC, NIC, and λHU in the AP and VP of MTs were higher than those of PAs (p < 0.001-0.047). Zeff and NIC in AP and λHU in VP were independent predictors with an AUC of 0.93 after the combination. Attenuation and Rho in the precontrast phase; attenuation, Rho, Zeff, DEI, IC, NIC, and λHU in AP; and the Rho in the VP of PAs were lower than those of WTs (p < 0.001-0.03). Rho in the precontrast phase and attenuation in AP were independent predictors with an AUC of 0.89 after the combination. MTs demonstrated higher Zeff, DEI, IC, NIC, and λHU in VP and lower Rho in the precontrast phase compared with WTs (p < 0.001-0.04); but no independent predictors were found. CONCLUSION: DECT quantitative parameters can help to differentiate PGTs.

Nitroglycerin improves the visibility of fibula-free flap perforators on computed tomography angiography in patients with oral or maxillofacial lesion.

PURPOSE: To investigate the improvement of image quality and visualization of fibula-free flap (FFF) perforators on computed tomography angiography (CTA) after administration of sublingual nitroglycerin (NTG) tablets. METHODS: A total of 60 patients with oral or maxillofacial lesions before CTA of the lower extremity were randomly divided into two groups (NTG group and non-NTG group). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), overall image quality and grading of vessels were evaluated and compared. The lumen diameters of the major arteries and the proximal and distal peroneal perforators were measured. The number of visible perforators in muscular clearance and muscular layer was also counted and compared between the two groups. RESULTS: The CNR of posterior tibial artery and overall image quality of CTA images in the NTG group was significantly higher than that in the non-NTG group (p < 0.05), although the SNR and CNR of other arteries did not show significant differences (p > 0.05). The lumen diameters of the peroneal artery and its perforators, anterior tibial artery, and posterior tibial artery were significantly larger in the NTG group (p < 0.001), while no significant difference prevailed in the diameter of the popliteal artery between the two groups (p = 0.298). Compared with the non-NTG group, a significant increase in the number of visible perforators was noted in the NTG group (p < 0.001). CONCLUSIONS: The administration of sublingual NTG in CTA of the lower extremity can improve the image quality and visualization of perforators, which aids to surgeons select the optimum FFF.

Morphologic CT and MRI features of primary parotid squamous cell carcinoma and its predictive factors for differential diagnosis with mucoepidermoid carcinoma.

BACKGROUND: Primary parotid squamous cell carcinoma (SCC) is a rare entity with a poor prognosis. Pathologically, the diagnosis of it requires the exclusion of parotid mucoepidermoid carcinoma (MEC). Currently, the imaging features of primary parotid SCC and the predictive indicators for differential diagnosis of the two entities have not been well reported. Our purpose was to identify the imaging characteristics of primary parotid SCC and to determine the predictive factors for its' differential diagnosis. RESULTS: Thirty-one participants with primary parotid SCC and 59 with primary parotid MEC were enrolled. Clinical, CT and MRI features were reviewed and compared by univariate analysis. Then, multinomial logistic regression was used to determine the predictors to distinguish parotid SCC from MEC. Most primary parotid SCCs exhibited irregular shape, ill-defined margin, incomplete or no capsule, heterogeneous and marked or moderate enhancement, necrosis, local tumor invasiveness (LTI). Age, maximal dimension, shape, degree of enhancement, gradual enhancement, necrosis, and LTI were different between the primary parotid SCCs and MECs in univariate analysis (p < 0.05). While in multinomial logistic regression analysis, only age and necrosis were the independent predictors for distinguishing parotid SCC from MEC, and this model exhibited an area under curve of 0.914 in ROC curve analysis. CONCLUSIONS: Primary parotid SCC has some distinct imaging features including the large tumor size, irregular shape, ill-defined margin, and particularly the marked central necrosis. Patients with age ≥ 51.5 years and necrosis on the image of the primary tumor in the parotid gland could be more likely to be SCCs than MECs.

Preoperative Prediction of the Aggressiveness of Oral Tongue Squamous Cell Carcinoma with Quantitative Parameters from Dual-Energy Computed Tomography.

Objectives: To determine whether quantitative parameters derived from dual-energy computed tomography (DECT) were predictive of the aggressiveness of oral tongue squamous cell carcinoma (OTSCC) including the pathologic stages, histologic differentiation, lymph node status, and perineural invasion (PNI). Methods: Between August 2019 and March 2021, 93 patients (mean age, 54.6 ± 13.8 years; 66 men) with pathologically diagnosed OTSCC were enrolled in this prospective study. Preoperative DECT was performed and quantitative parameters (e.g., slope of the spectral Hounsfield unit curve [λHu], normalized iodine concentration [nIC], normalized effective atomic number [nZeff], and normalized electron density [nRho]) were measured on arterial phase (AP) and venous phase (VP) DECT imaging. Quantitative parameters from DECT were compared between patients with different pathologic stages, histologic differentiation, lymph node statuses, and perineural invasion statuses. Logistic regression analysis was utilized to assess independent parameters and the diagnostic performance was analyzed by the receiver operating characteristic curves (ROC). Results: λHu and nIC in AP and λHu, nZeff, and nIC in VP were significantly lower in stage III-IV lesions than in stage I-II lesions (p < 0.001 to 0.024). λHu in VP was an independent predictor of tumor stage with an odds ratio (OR) of 0.29, and area under the curve (AUC) of 0.80. λHu and nIC were higher in well-differentiated lesions than in poorly differentiated lesions (p < 0.001 to 0.021). The nIC in VP was an independent predictor of histologic differentiation with OR of 0.31, and AUC of 0.78. λHu and nIC in VP were lower in OTSCCs with lymph node metastasis than those without metastasis (p < 0.001 to 0.005). λHu in VP was the independent predictor of lymph node status with OR of 0.42, and AUC of 0.74. No significant difference was found between OTSCCs without PNI and those with PNI in terms of the quantitative DECT parameters. Conclusion: DECT can be a complementary means for the preoperative prediction of the aggressiveness of OTSCC.

General Characteristics of Microbubble-Adenovirus Vectors Carrying Genes.

INTRODUCTION: Transferring genes safely, targeting cells and achieving efficient transfection are urgent problems in gene therapy that need to be solved. Combining microbubbles (MBs) and viruses to construct double vectors has become a promising approach for gene delivery. Understanding the characteristic performance of MBs that carry genes is key to promoting effective gene transfer. Therefore, in this study, we constructed MB-adenovirus vectors and discussed their general characteristics. METHODS: We constructed MB-adenovirus vectors carrying the chemokine (C-X-C motif) ligand 12 (Cxcl12) and bone morphogenetic protein-2 (Bmp2) genes (pAd-Cxcl12 and pAd-Bmp2, respectively) to explore the general characteristics of double vectors carrying genes. RESULTS: The MB-adenovirus vectors had stable physical properties, and no significant differences in diameter, concentration, or pH were noted compared with naked MBs (p > 0.05). Flow cytometry and RT-PCR were used to detect the gene-loading capacity of MBs. The gene-loading efficiency of MBs increased with increasing virus amounts and was highest (91%) when 10.0 µL of virus was added. Beyond 10.0 µL of added virus, the gene-loading efficiency of MBs decreased with the continuous addition of virus. The maximum amounts of pAd-Cxcl12 and pAd-Bmp2 in 100 µL of MBs were approximately 14 and 10 µL, respectively. CONCLUSIONS: This study indicates that addition of an inappropriate viral load will result in low MB loading efficiency, and the maximum amount of genes loaded by MBs may differ based on the genes carried by the virus.

Heat shock protein 70 attenuates hypoxia­induced apoptosis of pulmonary microvascular endothelial cells isolated from neonatal rats.

Pulmonary microvascular endothelial cell (PMVEC) apoptosis is the initial stage of adult pulmonary hypertension (PH), which involves high pulmonary arterial pressure and pulmonary vascular remodeling. However, the mechanism regulating PMVEC apoptosis and its involvement in the early stages of neonatal hypoxic PH (HPH) pathogenesis are currently unclear. The present study aimed to investigate the effects of heat shock protein 70 (HSP70) on hypoxia­induced apoptosis in PMVECs. PMVECs isolated from neonatal Sprague­Dawley rats were transfected with lentivirus with or without HSP70, or treated with the synthetic HSP70 inhibitor N­formyl­3,4­methylenedioxy­benzylidene-g-butyrolactam under hypoxic conditions (5% O2) for 24, 48 or 72 h. PMVEC apoptosis was evaluated by performing flow cytometry and mitochondrial membrane potential (MMP) assays. The expression levels of HSP70, hypoxia­inducible factor­1α (HIF­1α) and apoptosis­associated proteins were determined by conducting reverse transcription­quantitative PCR and western blotting. Following 24, 48 or 72 h of hypoxia, the apoptotic rates of PMVECs were significantly elevated compared with cells under normoxic conditions. The MMP was significantly reduced, whereas the mRNA and protein expression levels of HIF­1α, cytochrome c (cyt C), caspase­3 and HSP70 were enhanced by hypoxia compared with those under normoxic conditions. Additionally, the mRNA and protein expression levels of B­cell lymphoma 2 (Bcl­2) were significantly downregulated in the hypoxia group compared with those in the normoxia group. In hypoxic PMVECs, HSP70 overexpression decreased the apoptotic rate and the expression levels of cyt C, downregulated the expression levels of caspase­3 and HIF­1α, and increased the MMP and the expression levels of Bcl­2. HSP70 inhibition resulted in the opposite outcomes compared with those of HSP70 overexpression. Therefore, the results of the present study suggested that HSP70 may inhibit mitochondrial pathway­mediated apoptosis in isolated neonatal rat PMVECs in early­stage hypoxia, which may be associated with HSP70­mediated HIF­1α downregulation. Overall, HSP70 may be protective against neonatal HPH through the HSP70/HIF­1α pathway.

Experimental Study on the Compatibility and Characteristics of a Dual-Target Microbubble Loaded with Anti-miR-33.

OBJECTIVE: To prepare a new type of dual-target microbubble loaded with anti-miR-33 (ANM33). METHODS: Carrier core nanobubbles (NBs) were prepared by thin film hydration, and microbubbles loaded with PM1 (PCNBs) were prepared by grafting DSPE-PEG2000-maleimide-PM1 onto the NB surface. ANM33 was connected via electrostatic adsorption and covalent bonding, and hyaluronic acid (HA) was covalently connected. PM1 and HA were the targets, and ANM33 was the intervention drug. To evaluate the general physical and chemical properties of the prepared dual-target microbubbles loaded with ANM33 (HA-PANBs), we observed their morphology, particle size and surface potential while monitoring their stability and in vitro imaging ability, evaluated their toxic effect on cells and verified their ability to target cells. RESULTS: HA-PANBs had a regular morphology and good stability. The average particle size measured by a Malvern potentiometer was 1421.75±163.23 nm, and the average surface potential was -5.51±1.87 mV. PM1 and ANM33 were effectively connected to the NBs. The PM1, ANM33, and HA binding reached 89.0±1.1%, 65.02±5.0%, and 61.4±3.5%, respectively, and the maximum binding reached 2 µg, 5 µg, and 7 µg/108 microbubbles, respectively. HA-PANBs had no obvious toxic effects on cells, and their ability to continuously enhance imaging in vitro persisted for more than 15 minutes, obviously targeting foam cells in the early stage of AS. CONCLUSION: HA-PANBs are ideal ultrasound contrast agents. The successful, firm connection of PM1 and HA to the NBs significantly increased the amount of carried ANM33. When microbubbles prepared with 2:4:7 PM1:ANM33:HA were used as a contrast agent, they had a high ANM33 carrying capacity, stable physical properties, and significantly enhanced imaging and targeting of foam cells in the early stage of AS.