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.
Histological studies and morphometry quantitative analysis have been performed on trial rabbit’s dilated common bile duct(CBD),which does not dilate simultaneously.The results shows:①Epithelia of rabbit’s CBD have a ber reparable function,which is fairly significant to the prevention of bile duct’s further injure under the pathogenic situation.②The smooth muscle cell(SMC)of the CBD is the histological basis of contraction,some SMC can be seen in contracting state under light microscope.This indicates that the SMC in rabbit’s CBD possess contracting function.③The collagenous and elastic fibers have the normal histological morphometric characteristics and quantity in it’s dilatation process,and no breekdown and degeneration of the fibers can be detected.Because of the morphological structure of these sections is quite similiar with normal ones,theoretically,we suspect that when pathological change of bile duct’s distal portion is relieved and the bile pressure is normal again.It is possible for this dilating bile duct to return to its formal shape and size.
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 detect traces of microRNAs (miRNAs) in plasma and assess the expression stability of two common reference genes by stem-loop and poly A polymerase (PAP) real-time quantitative polymerase chain reaction (PCR) method, as miRNAs are the new bio-markers of tumor diagnosis and molecular targeted therapy, and its quantitative research is very important. Methods We extracted miRNAs from plasma of adult Sprague Dawley (SD) rats’ plasma, and detected the expressions of rno-miR-200b-3p and rno-miR-126-3p with stem-loop and PAP real-time PCR quantitative method, with rno-miR-103a-3p and U6 as internal controls. All the results were evaluated by 2△Ct method. Results Compared with PAP method, the stem-loop method reduced Ct value by 2-4 cycles and improved sensitivity by 10 times. In PAP method, the melting curve showed two peaks, a main peak and a small non-specific peak. Yet the melting curve of stem-loop method demonstrated a single specific peak. Furthermore, we validated the stability of internal references in the two real time PCR methods. U6 presented a more stable Ct value than rno-miR-103 in adult SD rats’ plasma samples. Conclusions Stem-loop real-time PCR is recommended as a major way to detect some samples with a low concentration of miRNAs, owing to its high accuracy and sensitivity. However, if a large number of tissue samples is going to be detected, PAP real-time PCR is more suitable and convenient than stem-loop method. U6 is more stable and repeatable than rno-miR-103a-3p as the reference gene to evaluate the semi-quantitative consequence of miRNAs.
Objective To scientifically evaluate the nosocomial infection prevention and control ability of respiratory infectious diseases in general hospitals, and to construct a set of quantitative assessment system for the prevention and control ability of respiratory infectious diseases in general hospitals. Methods Papers, standards and guidelines online related to respiratory hospital infections published between January 1, 2010 and December 31, 2023 were selected, and infection control experience was summarized to build a pool of evaluation pionts. Then, this study used experts consultation to select the evaluation pionts, to calculate the weight coefficient and reached a consensus on the quantitative evaluation methods of each evaluation point. Results A total of 27 articles were included. The evaluation system included 17 evaluation points in 4 categories: “Basic management capacity” “Basic conditions of facilities and equipments” “The prevention and control capacity of nosocomial infection” and “The emergency response capacity”. Each evaluation point contained 3 quantitative evaluation indicators. The Cronbach’s α coefficients of the expert questionnaire consultation were 0.914 and 0.883, respectively. The scale-level content validity index was 0.932, and the item-level content validity index ranged from 0.823 to 1. Conclusions The evaluation system constructed in this study can be used for quantitative evaluation and quality self-examination of the prevention and control ability of respiratory infectious diseases in general hospitals. It also contributes to the continuous improvement of the quality of nosocomial infection prevention and control.
ObjectiveTo evaluate the value of imaging quantification parameters in artificial intelligence (AI) assisted diagnosis systems in clinical decision-making for lung nodules≤2 cm and the diagnostic efficacy of AI. MethodsLung nodule patients admitted to Affiliated Zhongshan Hospital of Dalian University from 2020 to 2023 were included. Imaging parameters of lung nodules were extracted using AI assisted diagnosis systems. Multifactor analysis was used to screen predictors for distinguishing benign and malignant nodules and high-risk predictors for recurrent invasive adenocarcinoma, and a diagnostic model was established and its performance evaluated. The diagnostic efficacy of the AI system was judged according to pathological results. ResultsA total of 594 patients with lung nodules were included, including 202 males and 392 females, with an average age of (58.75±11.55) years. Volume, average CT value, and 3D maximum diameter of non-solid nodules were independent predictors of malignant nodules, with thresholds of 287.4 mm3, ?491 HU, and 12.0 mm, respectively. The area under the curve (AUC) for diagnostic efficacy was ranked from high to low as combined model (0.802), volume (0.783), average CT value (0.749), and 3D maximum diameter (0.714). The average CT value and 3D long diameter of solid nodules were independent predictors of malignant nodules, with thresholds of ?81 HU and 17.5 mm, respectively, and AUC values of 0.874 and 0.686, respectively, with the combined prediction AUC of 0.957. The mass of cystic nodules was an independent predictor of malignancy when the mass>180.7 mg. Independent predictors of high recurrence risk of invasive adenocarcinoma in non-solid nodules were consolidation-tumor ratio (CTR), average CT value, 3D long diameter, and volume, with thresholds of 0.14, ?386 HU, 15.6 mm, and 1018.9 mm3, respectively, and diagnostic efficacy was ranked from high to low as combined model (0.788), 3D long diameter (0.735), volume (0.725), average CT value (0.720), and CTR (0.697). The accuracy of AI in predicting benign and malignant target nodules was 87.4%, with positive predictive value of 96.6% and negative predictive value of 58.9%. ConclusionIn clinical decision-making for lung nodules ≤2 cm, AI assisted diagnosis systems have high application value.
ObjectiveTo investigate the value of CT-based radiomics and clinical data in predicting the efficacy of non-vascularized bone grafting (NVBG) in hip preservation, and to construct a visual, quantifiable, and effective method for decision-making of hip preservation. Methods Between June 2009 and June 2019, 153 patients (182 hips) with osteonecrosis of the femoral head (ONFH) who underwent NVBG for hip preservation were included, and the training and testing sets were divided in a 7∶3 ratio to define hip preservation success or failure according to the 3-year postoperative follow-up. The radiomic features of the region of interest in the CT images were extracted, and the radiomics-scores were calculated by the linear weighting and coefficients of the radiomic features after dimensionality reduction. The clinical predictors were screened using univariate and multivariate Cox regression analysis. The radiomics model, clinical model, and clinical-radiomics (C-R) model were constructed respectively. Their predictive performance for the efficacy of hip preservation was compared in the training and testing sets, with evaluation indexes including area under the curve, C-Index, sensitivity, specificity, and calibration curve, etc. The best model was visualised using nomogram, and its clinical utility was assessed by decision curves. ResultsAt the 3-year postoperative follow-up, the cumulative survival rate of hip preservation was 70.33%. Continued exposure to risk factors postoperative and Japanese Investigation Committee (JIC) staging were clinical predictors of the efficacy of hip preservation, and 13 radiomic features derived from least absolute shrinkage and selection operator downscaling were used to calculate Rad-scores. The C-R model outperformed both the clinical and radiomics models in predicting the efficacy of hip preservation 1, 2, 3 years postoperative in both the training and testing sets (P<0.05), with good agreement between the predicted and observed values. A nomogram constructed based on the C-R model showed that patients with lower Rad-scores, no further postoperative exposure to risk factors, and B or C1 types of JIC staging had a higher probability of femoral survival at 1, 2, 3 years postoperatively. The decision curve analysis showed that the C-R model had a higher total net benefit than both the clinical and radiomics models with a single predictor, and it could bring more net benefit to patients within a larger probability threshold. Conclusion The prediction model and nomogram constructed by CT-based radiomics combined with clinical data is a visual, quantifiable, and effective method for decision-making of hip preservation, which can predict the efficacy of NVBG before surgery and has a high value of clinical application.
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.
Objective To investigate the gene expression of beta-defensin-4 (mBD-4) and mBD-6 in acute lung injury (ALI) mouse.Methods Sixty adult mice were randomly divided into a control group and a ALI group.ALI was induced by intraperitoneal injection of lipopolysaccharide (LPS) in the ALI group.The control group was treated with same dose of normal saline.The lung tissues were harvested at different time point after stimulation.The expression of mBD-4 and mBD-6 mRNA was measured by real-time quantitative reverse transcription polymerase chain reaction.DNA sequencing was used to confirm the specificity of mBD-4 and mBD-6 cDNA fragment.Results There were no obvious mBD-4 and mBD-6 mRNA expression in mouse lung in the control group at all time points and ALI 6 h group.In the ALI group a marked increasing expression was found on 12 h，1 d and 3 d after LPS stimulation.The mBD-4 mRNA expression was significant higher in the ALI groups of 1 d and 3 d points than that of ALI 12 h group with no obvious difference between each other.There were no significant differences of mBD-6 mRNA expression between ALI groups of 12 h，1 d and 3 d points Conclusion mBD-4 and mBD-6 mRNA is not constitutive expressed in mouse lung and show a up-regulative expression pattern after ALI.
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.