Objective To summarize the research progress of magnetic resonance quantitative technique in the iron overload of the abdominal parenchyma organ. Methods By reviewing the related literatures domesticly and abroad, the present status and progress of abdominal magnetic resonance quantitative technique and other examinations in the study of iron overload were analyzed. Results MRI multi-sequence examination technique had changed the research model of iron overload in different organs, and had important clinical significance in imaging diagnosis of abdominal parenchyma organ damage. so far, many techniques of MRI had been used in detection of iron overload, which included signal intensity measurements(including signal intensity ratio and signal intensity difference of positive and negative phases), T2/R2 measurements, T2*/R2* measurements, Dixon and its derivatization, ultrashort echo time technique and susceptibility weighted imaging (including conventional susceptibility weighted imaging and quantitative magnetic sensitive imaging). Conclusion Magnetic resonance quantitative examination technique is expected to be the first choice for detection of hepatic iron overload, and can improve the early detection rate of iron overload pancreatic damage.
The new mechanisms of automaticity controlled by the calcium and membrane clocks in sinoatrial node are helpful to revealing the sinus arrhythmia, but the present calcium dynamic model is only on the single cell level. In the present study, a central and peripheral single cell model was developed, and by exponentially changing the cell membrane capacitance, size, conductance and gap junction from the center to the periphery, a two-dimensional inhomogeneous sinus and atrial model was created on the basis of the anatomical structure. Five-point difference and finite element methods were used to process the internal grids and the borders. Irregular borders were defined by creating segment trial functions. Quantitative experiments suggested the consistency of the central and peripheral action potentials with related reports in amplitude, cycle length, maximum diastolic potential and upstroke velocity. Functions of the calcium and membrane clocks on the leading pacemaker site and upstroke velocity as well as the effects of the atrial premature beat on the sinus automaticity were also in good agreement with those in other studies. The developed model is helpful for deeply studying relative roles of the calcium and membrane clocks in automaticity and the relations with electrical activities in atrium. At the same time it will lay the foundation for building three-dimensional sinus and atrial organic models.
ObjectiveTo summarize the methods and research progress of imaging evaluation of liver iron concentration.MethodsThe current status and progress of different imaging techniques in liver iron overload research were reviewed by studying the relevant literatures at home and abroad. The methods for determining liver iron concentration and their advantages and disadvantages were summarized.ResultsThe imaging methods for determining liver iron concentration mainly included traditional non-enhanced CT and dual energy CT examination, magnetic resonance signal intensity ratio, relative signal intensity index, T2 and R2 values, magnetic resonance spectroscopy, T2* and R2* values, susceptibility weighted imaging, and quantitative susceptibility mapping.ConclusionLiver iron quantification imaging method, including dual-energy CT and magnetic resonance imaging could non-invasively and accurately assess the liver iron overload.
Objective To evaluate branched-chain DNA (b-DNA) signal amplification and semi-quantitative (Sq) RT-PCR in detection of free cancer cells in peritoneal flushing fluid of colorectal cancer patients during surgery. Methods The CEA mRNA in peritoneal flushing fluid in 48 cases of colorectal cancer were detected by b-DNA and SqRT-PCR. Peritoneal flushing fluid cytology (PLC) was conformed simultaneously to detect the free cancer cells. The peritoneal flushing fluid of 12 cases with colorectal benign disease were taken as negative control, GAPDH mRNA as internal control. Results In colorectal cancer patients, positive rate of free cancer cells by bDNA and SqRT-PCR （43.8%, 31.3%） was higher than that by PLC （4.2%）. The relative quantitative expressions of CEA mRNA were related to the Dukes staging， depth invasion and differentiation degree (Plt;0.05)， but irrelevant to tumor size，the patients’ age and gender (Pgt;0.05).Conclusion Both b-DNA and SqRT-PCR technologies have advantages and disadvantages to detect free cancer cells in peritoneal flushing fluid， which are related to clinicopathological factors.
Intravascular optical coherence tomography (IVOCT) has emerged as a high-resolution and minimal-invasive imaging technique that provides high-speed visualization of coronary arterial vessel walls and clearly displays the vessel lumen and lesions under the intima. However, morphological gray-scale images cannot provide enough information about the tissue components to accurately characterize the plaque tissues including calcified, fibrous, lipidic and mixed plaques. Quantitative IVOCT (qIVOCT) is necessary to provide the physiological contrast mechanisms and obtain the characteristic parameters of tissues with clinical diagnostic value. In this paper, the progress of qIVOCT is reviewed. The current methods for quantitatively measuring optical, elastic and hemodynamic parameters of vessel wall and plaque tissues using IVOCT gray-scale images and raw backscattered signals are introduced and potential development is forecast.
Objective To explore the clinical value of artificial intelligence (AI) quantitative parameters in distinguishing pathological grades of stageⅠ invasive adenocarcinoma (IAC). Methods Clinical data of patients with clinical stageⅠ IAC admitted to Yantaishan Hospital Affiliated to Binzhou Medical University from October 2018 to May 2023 were retrospectively analyzed. Based on the 2021 WHO pathological grading criteria for lung adenocarcinoma, IAC was divided into gradeⅠ, grade Ⅱ, and grade Ⅲ. The differences in parameters among the groups were compared, and logistic regression analysis was used to evaluate the predictive efficacy of AI quantitative parameters for grade Ⅲ IAC patients. Parameters were screened using least absolute shrinkage and selection operator (LASSO) regression analysis. Three machine learning models were constructed based on these parameters to predict grade Ⅲ IAC and were internally validated to assess their efficacy. Nomograms were used for visualization. ResultsA total of 261 IAC patients were included, including 101 males and 160 females, with an average age of 27-88 (61.96±9.17) years. Six patients had dual primary lesions, and different lesions from the same patient were analyzed as independent samples. There were 48 patients of gradeⅠ IAC, 89 patients of grade Ⅱ IAC, and 130 patients of grade Ⅲ IAC. There were statitical differences in the AI quantitive parameters such as consolidation/tumor ratio (CTR), ect among the three goups. (P<0.05). Univariate analysis showed that the differences in all variables except age were statistically significant (P<0.05) between the group gradeⅠ+grade Ⅱand the group grade Ⅲ . Multivariate analysis suggested that CTR and CT standard deviation were independent risk factors for identifying grade Ⅲ IAC, and the two were negatively correlated. Grade Ⅲ IAC exhibited advanced TNM staging, more pathological high-risk factors, higher lymph node metastasis rate, and higher proportion of advanced structure. CTR was positively correlated with the proportion of advanced structures in all patients. This correlation was also observed in grade Ⅲ but not in gradeⅠand grade ⅡIAC. CTR and CT median value were selected by using LASSO regression. Logistic regression, random forest, and XGBoost models were constructed and validated, among which, the XGBoost model demonstrated the best predictive performance. Conclusion Cautious consideration should be given to grade Ⅲ IAC when CTR is higher than 39.48% and CT standard deviation is less than 122.75 HU. The XGBoost model based on combined CTR and CT median value has good predictive efficacy for grade Ⅲ IAC, aiding clinicians in making personalized clinical decisions.
Objective To observe whether Cyclo-RGDfK (Arg-Gly-Asp-D-Phe-Lys) could enhance the adhesion of myofibroblast to decellularized scaffolds and upregulate the expression of Integrin αVβ3 gene. Methods Myofibroblast from the rat thoracic aorta was acquired by primary cell culture. The expression of Vimentin and α-smooth muscle actin(α-SMA) has been detected by immunoflurescent labeling. Decellularized valves have been randomly divided into three groups (each n=7). Group A (blank control): valves do not receive any pretreatment; Group B: valves reacted with linking agent NEthylN(3dimethylaminopropyl)carbodiimide hydrochloride (EDC) for 36 hours before being seeded; Experimental group: Cyclo-RGD peptide has been covalently immobilized onto the surface of scaffolds by linking agent EDC. The fifth generation of myofibroblast has been planted on the scaffolds of each group. The adhesion of myofibroblast to the scaffolds was evaluated by HE staining and electron scanning microscope. The expression of Integrin αVβ3 was quantified by halfquantitative reverse transcriptionpolymerase china reaction (RT-PCR). Results We can see that myofibroblast has exhibited b positive staining for Vimentin and α-SMA. Besides, it has been shown that the expression of Integrin αVβ3 was much higher in the experimental group than that of the group A and group B(Plt;0.05). There was no statistically difference in group A and group B (P=0.900). Conclusion RGD pretreatment does enhance the adhesive efficiency of seeding cells to the scaffolds and this effect may be related to the upregulation of Integrin αVβ3.
Effective medical image enhancement method can not only highlight the interested target and region, but also suppress the background and noise, thus improving the quality of the image and reducing the noise while keeping the original geometric structure, which contributes to easier diagnosis in disease based on the image enhanced. This article carries out research on strengthening methods of subtle structure in medical image nowadays, including images sharpening enhancement, rough sets and fuzzy sets, multi-scale geometrical analysis and differential operator. Finally, some commonly used quantitative evaluation criteria of image detail enhancement are given, and further research directions of fine structure enhancement of medical images are discussed.
The β-secretase is one of prospective targets against Alzheimer's disease (AD). A three-dimensional quantitative structure-activity relationship (3D-QSAR) model of Hydroethylamines (HEAs) as β-secretase inhibitors was established using Topomer CoMFA. The multiple correlation coefficient of fitting, cross validation and external validation were r2=0.928, qloo2=0.605 and rpred2=0.626, respectively. The 3D-QSAR model was used to search R groups from ZINC database as the source of structural fragments. As a result, a series of R groups with relatively high activity contribution was obtained to design a total of 15 new compounds, with higher activity than that of the template molecule. The molecular docking was employed to study the interaction mode between the new compounds as ligands and β-secretase as receptors, displaying that hydrogen bond and hydrophobicity played important roles in the binding affinity between the new compounds and β-secretase. The results showed that Topomer CoMFA and Topomer Search could be effectively used to screen and design new molecules of HEAs as β-secretase inhibitors, and the designed compounds could provide new candidates for drug design targeting AD.
Objective To investigate the detection of peritoneal free cancer cells and its clinical significance. Methods The peritoneal free cancer cells, the positive rates of CK20 protein and CK20 mRNA expressions of peritoneal lavage fluid were detected by peritoneal lavage cytology (PLC), flow cytometry (FCM) and real-time fluorescent quantitative RT-PCR in 50 cases of gastric cancer patients, respectively. The sensitivity of three kinds of detection method to peritoneal free cancer cells was compared. Results The positive rates of peritoneal free cancer cells, CK20 protein and mRNA expression of peritoneal lavage fluid were 20.0% (10/50), 36.0% (18/50) and 58.0% (29/50), respectively. The positive rate of CK20 mRNA expression detected by real-time fluorescencequantitative RT-PCR in peritoneal lavage fluid was significantly higher than those of the CK20 protein expression detected by FCM and peritoneal free cancer cells detected by PLC (Plt;0.05 or Plt;0.001). The difference of positive rate of CK20 protein expression and peritoneal free cancer cells was not significant (Pgt;0.05). The positive rate of CK20 mRNA expression of peritoneal lavage fluid was related to the tumor invasion depth, differentiation degree, TNM stage, and lymph node metastasis (Plt;0.05). Conclusion Real-time fluorescence quantitative RT-PCR is an effective method for the detection of peritoneal free cancer cells.