Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Based on the interaction between supramolecule of traditional Chinese medicine and enterobacteria, the material basis of Rhei Radix et Rhizoma and Coptidis Rhizoma was explored. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) were used to characterize the morphological differences of Rhubarb single decoction, Coptis single decoction and Rhubarb and Coptis co-decoction. An in vitro antibacterial model (E. coli, E. faecium and B. subtilis) was established to evaluate the damage effect of the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma on enterobacteria. Ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to analyze the changes of chemical components of single decoctions and co-decoctions. The co-decoction of Rhei Radix et Rhizoma and Coptidis Rhizoma was turbid after decocting. The spherical particles of 300-400 nm were observed under SEM, and the co-decoction was more uniform and stable than that of single decoction. The interaction between supramolecules formed after the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma and enterobacteria was significantly different from that of single decoction. In the process of interaction between supramolecules and enterobacteria, the spherical state was maintained, and the medicinal ingredients in Coptidis Rhizoma or Rhei Radix et Rhizoma were blocked, which could effectively alleviate the damage to enterobacteria. This study provided a reference for subsequent studies on the regulation of intestinal flora homeostasis by the combination of Rhei Radix et Rhizoma and Coptidis Rhizoma.

Objective To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine(MDMA)and its metabolite 4,5-methylene dioxy amphetamine(MDA)in rats af-ter single and continuous administration of MDMA,providing reference data for the forensic identifica-tion of MDMA.Methods A total of 24 rats in the single administration group were randomly divided into 5,10 and 20 mg/kg experimental groups and the control group,with 6 rats in each group.The ex-perimental group was given intraperitoneal injection of MDMA,and the control group was given intraperi-toneal injection of the same volume of normal saline as the experimental group.The amount of 0.5 mL blood was collected from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.In the continuous administration group,24 rats were randomly divided into the experi-mental group(18 rats)and the control group(6 rats).The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5,7,9,11,13,15,17 mg/kg per day,respectively,while the control group was given the same volume of normal saline as the experimental group by in-traperitoneal injection.On the eighth day,the experimental rats were randomly divided into 5,10 and 20 mg/kg dose groups,with 6 rats in each group.MDMA was injected intraperitoneally,and the con-trol group was injected intraperitoneally with the same volume of normal saline as the experimental group.On the eighth day,0.5 mL of blood was taken from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels,and statistical software was employed for data analysis.Results In the single-administration group,peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration,respectively,with the largest detection time limit of 12 h.In the continuous administration group,peak concentrations were reached at 30 min and 1.5 h af-ter administration,respectively,with the largest detection time limit of 10 h.Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows:T=10.362C-1.183,R2=0.974 6;T=7.397 3C-0.694,R2=0.961 5(T:injection time;C:concentration ratio of MDMA to MDA in plasma).Conclusions The toxicokinetic data of MDMA and its metabolite MDA in rats,obtained through single and continuous administration,including peak concentration,peak time,detection time limit,and the relationship between concentration ratio and administration time,provide a theoretical and data foundation for relevant forensic identification.

ObjectiveIn recent years, with the intensification of environmental issues and the depletion of ozone layer, incidence of skin tumors has also significantly increased, becoming one of the major threats to people’s lives and health. However, due to factors such as high concealment in the early stage of skin tumors, unclear symptoms, and large human skin area, most cases are detected in the middle to late stage. Early detection plays a crucial role in postoperative survival of skin tumors, which can significantly improve the treatment and survival rates of patients. We proposed a rapid non-invasive electrical impedance detection method for early screening of skin tumors based on bioimpedance spectroscopy (BIS) technology. MethodsFirstly, we have established a complete skin stratification model, including stratum corneum, epidermis, dermis, and subcutaneous tissue. And the numerical analysis method was used to investigate the effect of dehydrated and dry skin stratum corneum on contact impedance in BIS measurement. Secondly, differentiation effect of different diameter skin tumor tissues was studied using a skin model after removing the stratum corneum. Then, in order to demonstrate that BIS technology can be used for detecting the microinvasion stage of skin tumors, we conducted a simulation study on the differentiation effect of skin tumors under different infiltration depths. Finally, in order to verify that the designed BIS detection system can distinguish between tumor microinvasion periods, we conducted tumor invasion experiments using hydrogel treated pig skin tissue. ResultsThe simulation results show that a dry and high impedance stratum corneum will bring about huge contact impedance, which will lead to larger measurement errors and affect the accuracy of measurement results. We extracted the core evaluation parameter of relaxed imaginary impedance (Z_imag-relax) from the simulation results of the skin tumor model. When the tumor radius (R_tumor) and invasion depth (h)>1.5 mm, the designed BIS detection system can distinguish between tumor tissue and normal tissue. At the same time, in order to evaluate the degree of canceration in skin tissue, the degree of tissue lesion (ε_worse) is defined by the relaxed imaginary impedance (Z_imag-relax) of normal and tumor tissue (ε_worse is the percentage change in virtual impedance of tumor tissue relative to that of normal tissue), and we fitted a Depth-Z_imag-relax curve using relaxation imaginary impedance data at different infiltration depths, which can be applied to quickly determine the infiltration depth of skin tumors after being supplemented with a large amount of clinical data in the future. The experimental results proved that when ε_worse=0.492 0, BIS could identify microinvasive tumor tissue, and the fitting curve correction coefficient of determination was 0.946 8, with good fitting effect. The simulation using pig skin tissue correlated the results of real human skin simulation with the experimental results of pig skin tissue, proving the reliability of this study, and laying the foundation for further clinical research in the future. ConclusionOur proposed BIS method has the advantages of fast, real-time, and non-invasive detection, as well as high sensitivity to skin tumors, which can be identified during the stage of tumor microinvasion.

Lung cancer is the leading type of cancer death, and most patients with lung cancer are diagnosed at an advanced stage and have a very poor prognosis. Although low-dose computed tomography (LDCT) has entered the clinic as a screening tool for lung cancer, its false-positive rate is more than 90%. As one of the epigenetic modifications of research hotspots, DNA methylation plays a key role in a variety of diseases, including cancer.Hypermethylation of tumor suppressor genes and hypomethylation of proto-oncogenes are important events in tumorigenesis and development. Therefore, DNA methylation analysis can provide some useful information for the early screening, diagnosis, treatment and prognosis of lung cancer. Although invasive methods such as tissue biopsy remain the gold standard for tumor diagnosis and monitoring, they also have limitations such as inconvenience in sampling. In recent years, there has been a rapid development of liquid biopsy, which can detect primary or metastatic malignancies and reflect the heterogeneity of tumors. In addition, the blood sample can be collected in a minimally invasive or non-invasive format and is well tolerated in older and frail patients. This article explores some of the emerging technologies for DNA methylation analysis and provides an overview of the application of DNA methylation in the diagnosis and treatment of lung cancer.

Objective To explore the application of metagenomic next-generation sequencing(mNGS)technology in the investigation of healthcare-associated infection(HAI)outbreaks of carbapenem-resistant Acinetobacter bau-mannii(CRAB).Methods Pathogenic detection by mNGS and conventional pathogen culture were performed on 5 patients in the intensive care unit(ICU)of a hospital from June 8 to 22,2023 from whom CRAB were detected.Microbial sampling was carried out in potentially contaminated environment.Bacterial culture,identification,and antimicrobial susceptibility testing were conducted.Comprehensive control measures were taken,and the effect was evaluated.Results The time required for reporting results by mNGS was shorter than the culture time([3.92± 1.05]days vs[6.24±0.25]days,P＜0.001).CRAB was isolated from the specimens of 5 patients.mNGS de-tected OXA-23 resistance genes from all patients.After comprehensive assessment by experts,4 patients were HAI and 1 patient was due to specimen contamination.According to the definition from Guidelines for HAI outbreak control,this event was considered an outbreak of HAI.The monitoring results of environmental hygiene showed that the detection rate of CRAB in the environment during the outbreak was 51.30％(59/115),mainly from the hands of health care workers and the surface of ventilators.After implementing multidisciplinary infection control measures,clinicians'hand hygiene compliance rate and implementation rate of ventilator disinfection increased from 40.83％(49/120)and 33.33％(16/48)to 82.61％(95/115)and 83.33％(30/36),respectively.The prognosis of patients was good,and no new case emerged during subsequent monitoring.The outbreak of HAI in this hospital has been effectively controlled.Conclusion mNGS is characterized by high precision,less time consumption,and high accuracy,and can be applied to the prevention and control of HAI outbreak and the study of antimicrobial-re-sistant genomes.It is of great significance for the anti-infection treatment of patients with multidrug-resistant orga-nism infection as well as the formulation of HAI prevention and control measures.Continuous improving disinfec-tion effectiveness and hand hygiene compliance is important for preventing and controlling CRAB infection.