With the rapid increase in the ownership of MRI equipment in China,quality control,particularly in clinical usage aspects,has become critically important.For clinical quality control of MRI systems,it is essential to establish comprehensive workflow principles encompassing multiple elements such as personnel,equipment,standards,tools and methodologies.To advance the standardization and widespread adoption of clinical quality control for MRI equipment,efforts must focus on strengthening regulatory frameworks,advancing phantom research,development and enhancing professional expertise.Concurrently,continuous improvements in training programs and supervision mechanisms are necessary to ensure the effective implementation of MRI clinical quality control practices.Furthermore,in the era of digital healthcare,clinical quality assurance for MRI equipment is evolving toward automation and intelligent solutions,providing higher-quality and more efficient assurance for clinical applications.

Objective:To investigate the molecular epidemiological characteristics of norovirus (NoV) among infectious diarrhea patients in Linyi from 2021 to 2023, and provide the scientific evidence for norovirus control and prevention.Methods:The epidemiological information and fecal samples of patients with infectious diarrhea in Linyi from 2021 to 2023 were collected and detected by real-time fluorescent quantitative PCR. The RdRp and capsid gene VP1 region of norovirus-positive specimens were amplified and sequenced used to analyze their genotype, phylogeny and homology.Results:Among the 2 311specimens, 123 (5.32%) were positive of NoV, with GI/GII group infection accounted for 17.07% (21/123) and 77.24% (95/123), respectively, GI/GII group mixed infection accounted for 5.69% (7/123). The detection rate of <1 year age group was the highest (8.86%), followed by the 1-3 years group (7.11%, 30/422) and the over 60 years group (5.29%, 23/123). The highest NoV detection rate was 7.96% (45/565) in the urban area, and the most abundant genotypes were found in the northern mountainous area. Sequence analysis showed that 61 identified NoV strains could be divided into 12 genotypes, with 4 NoV GI and 8 NoV GII. The dominant genotype differed during the 3 years, with GII.4 Sydney [P16] in 2021, GII.4 Sydney [P31] in 2022, and GII.2[P16] in 2023.Conclusions:NoV GII group was the main NoV infection in Linyi from 2021-2023 and genotypes were diverse. Children under 3 years of age and elderly people over 60 years old as susceptible groups should be given special protection. In addition, the monitoring of NoV genotype diversification should be strengthened in northern mountainous areas.

With the rapid increase in the ownership of MRI equipment in China,quality control,particularly in clinical usage aspects,has become critically important.For clinical quality control of MRI systems,it is essential to establish comprehensive workflow principles encompassing multiple elements such as personnel,equipment,standards,tools and methodologies.To advance the standardization and widespread adoption of clinical quality control for MRI equipment,efforts must focus on strengthening regulatory frameworks,advancing phantom research,development and enhancing professional expertise.Concurrently,continuous improvements in training programs and supervision mechanisms are necessary to ensure the effective implementation of MRI clinical quality control practices.Furthermore,in the era of digital healthcare,clinical quality assurance for MRI equipment is evolving toward automation and intelligent solutions,providing higher-quality and more efficient assurance for clinical applications.

Objective:To investigate the molecular epidemiological characteristics of norovirus (NoV) among infectious diarrhea patients in Linyi from 2021 to 2023, and provide the scientific evidence for norovirus control and prevention.Methods:The epidemiological information and fecal samples of patients with infectious diarrhea in Linyi from 2021 to 2023 were collected and detected by real-time fluorescent quantitative PCR. The RdRp and capsid gene VP1 region of norovirus-positive specimens were amplified and sequenced used to analyze their genotype, phylogeny and homology.Results:Among the 2 311specimens, 123 (5.32%) were positive of NoV, with GI/GII group infection accounted for 17.07% (21/123) and 77.24% (95/123), respectively, GI/GII group mixed infection accounted for 5.69% (7/123). The detection rate of <1 year age group was the highest (8.86%), followed by the 1-3 years group (7.11%, 30/422) and the over 60 years group (5.29%, 23/123). The highest NoV detection rate was 7.96% (45/565) in the urban area, and the most abundant genotypes were found in the northern mountainous area. Sequence analysis showed that 61 identified NoV strains could be divided into 12 genotypes, with 4 NoV GI and 8 NoV GII. The dominant genotype differed during the 3 years, with GII.4 Sydney [P16] in 2021, GII.4 Sydney [P31] in 2022, and GII.2[P16] in 2023.Conclusions:NoV GII group was the main NoV infection in Linyi from 2021-2023 and genotypes were diverse. Children under 3 years of age and elderly people over 60 years old as susceptible groups should be given special protection. In addition, the monitoring of NoV genotype diversification should be strengthened in northern mountainous areas.

Objective: To analyze the characteristics of influenza virus detection in an influenza outbreak in schools, so as to provide a strategic basis for the treatment of influenza outbreaks in schools. Methods: A total of 1 702 samples were collected from 52 school influenza outbreaks reported in Linyi City in 2021-2022. The samples were divided into 3 types according to different symptoms during the management of the epidemic [group A:influenzalike illness (ILI) group; group B:mild illness group; group C:close contacts group]. Rt-PCR was used to detect influenza virus nucleic acid in the collected samples. The detection rate of influenza virus in the outbreaks was analyzed by χ2 test. Results: In total, 1 071 samples (62.93%) tested positive for influenza virus nucleic acid. Among them, 610 out of 726 samples (84.02%) were detected in group A, while 331 out of 634 samples (52.21%) were detected in group B. In group C, 130 out of 342 samples (38.01%) tested positive. The differences were statistically significant (χ2=260.71, P<0.01). In group A, males had a detection rate of 80.83% for influenza virus nucleic acid, compared to 91.36% for females. For group B, the rates were 53.31% for males and 50.87% for females. In group C, males had a rate of 30.72%, while females had a rate of 43.92%. Statistical significance for gender differences was observed only in groups A and C (χ2=12.67, 6.25, P<0.05). According to the days of onset, the detection rates of influenza virus nucleic acid among patients with onset 0-6 days were 56.30%, 74.49%, 89.35%, 86.23%, 69.67%, 62.75%, 34.33%, respectively, and the difference was statistically significant (χ2=128.27, P<0.01). Conclusions Mild cases and close contacts are likely key factors contributing to the prolonged emergence of new cases within classrooms during school influenza outbreaks. The progression of influenza symptoms is related to the risk of transmission.

BACKGROUND:Establishing a nomogram prediction model for postoperative pulmonary infection in hip fractures and taking early intervention measures is crucial for improving patients'quality of life and reducing medical costs. OBJECTIVE:To construct a nomogram risk prediction model of postoperative pulmonary infection in elderly patients with hip fracture,and provide theoretical basis for feasible prevention and early intervention. METHODS:Case data of 305 elderly patients with hip fractures who underwent surgical treatment at Wuxi Traditional Chinese Medicine Hospital Affiliated to Nanjing University of Chinese Medicine between January and October 2020(training set)were retrospectively analyzed.Using univariate and multivariate logistic regression analysis and Hosmer-Lemeshow goodness of fit test,receiver operating characteristic curve was utilized to analyze the diagnostic predictive efficacy of independent risk factors and joint models for postoperative pulmonary infections.Tools glmnet,pROC,and rms in R Studio software were applied to construct a nomogram model for predicting the risk of postoperative pulmonary infection in elderly patients with hip fractures,and calibration curves were further drawn to verify the predictive ability of the nomogram model.Receiver operating characteristic curves,calibration curves,and decision curves were analyzed for 133 elderly patients with hip fractures(validation set)receiving surgery at the same hospital from November 2022 to March 2023 to further predict the predictive ability of the nomogram model. RESULTS AND CONCLUSION:(1)The postoperative pulmonary infection rate in elderly patients with hip fractures in this group was 9.18%(28/305).(2)Single factor and multivariate analysis,as well as forest plots,showed that preoperative hospitalization days,leukocyte count,hypersensitive C-reactive protein,and serum sodium levels were independent risk factors(P<0.05).The Hosmer-Lemeshow goodness of fit test showed good fit(χ2=4.57,P=0.803).Receiver operating characteristic curve analysis was conducted on the independent risk factors and their joint models mentioned above,and the differentiation of each independent risk factor and joint model was good,with statistical significance(P<0.05).(3)The graphical calibration method,C-index,and decision curve were used to validate the nomogram prediction model.The predicted calibration curve was located between the standard curve and the acceptable line,and the predicted risk of the nomogram model was consistent with the actual risk.(4)The validation set used receiver operating characteristic curve,graphic calibration method,and decision curve to validate the prediction model.The results showed good consistency with clinical practice,indicating that the model had a good fit.The nomogram risk prediction model constructed for postoperative pulmonary infection in elderly patients with hip fractures has good predictive performance.The use of the nomogram risk prediction model can screen high-risk populations and provide a theoretical basis for early intervention.

Acute gastrointestinal dysfunction is a common and important complication of sepsis. As no exiting formal definition and classification of gastrointestinal dysfunction, most of the treatment strategies for gastrointestinal dysfunction are not based on clinical evidence, but on their own clinical experience. Experts of traditional Chinese medicine, integrated traditional Chinese and Western medicine and Western medicine from various disciplines in Shanghai are organized by the Shanghai Society of Integrated Traditional Chinese and Western Medicine and the Emergency Department Branch of Shanghai Physicians Association. After repeated discussion, literature search and formulation of the outline, we developed consensus on gastrointestinal dysfunction secondary to sepsis with integrating Traditional Chinese Medicine and Western medicine by consulting extensively on clinical experts in the fields of emergency medicine, gastroenterology, general surgery, infectious medicine and traditional Chinese medicine, and holding several expert forums and consultation meetings. This clinical expert consensus focused on acute gastrointestinal injury (AGI) classification and inducer of sepsis. In this consensus, the common symptoms, diagnosis, classifications, treatment strategies and suggestions of acute gastrointestinal injury or dysfunction secondary to sepsis were explored from the aspect of both Traditional Chinese Medicine and Western medicine.

Objective To study the effect of storage duration on compressive mechanical properties of rabbit patellar, so as to provide references for in vitro ligament storage.Methods The compressive mechanical properties of rabbit patellar ligament storaged at -20 ℃ at different storage durations (in 36 d) were tested with the universal tensile test machine. The microscopic morphology of collagen fibers was observed under the scanning electron microscopy (SEM). The enthalpy and denaturation temperature of collagen fibers were measured with differential scanning calorimetry (DSC).Results With the increase of storage duration, the compressive stress of the patellar ligament at 40% strain increased from 19 kPa to 112 kPa and then decreased to 57 kPa. SEM observation showed that the cross-linking of collagen fibers was initially strengthened and then weakened. DSC results showed that the enthalpy increased from 59.47 J/g to 67.10 J/g and then decreased to 54.43 J/g. The denaturation temperature increased from 67.62 ℃ to 77.28 ℃ and then decreased to 64.10 ℃.Conclusions When rabbit patellar ligament is stored at -20 ℃, with the increase of storage duration, the compressive stress of rabbit patellar ligament at 40% strain increases at first and then decreases. This change may be due to the variation of cross-linking level of collagen fibers. The stronger the cross-linking of collagen fibers, the stronger the compressive mechanical properties will be.

Objective:To explore the application value of single source dual energy CT (DECT) scanning technique in improving the image quality of the pancreas.Methods:Imaging data of 21 patients with normal pancreas and 36 patients with pancreas related diseases in the First Affiliated Hospital of Naval Medical University from July 2021 to August 2021 were collected. All the patients first underwent multi-slice CT (MDCT) scan with no-contrast, and then dynamic enhanced MDCT scan. And the DECT scan was used in the delay period. Virtual single energy images (VMI, 40~100keV) of normal pancreas and mixed energy images of pancreatic lesions (PI, 80 and 140kVp) were obtained. The regions of interest (ROI) of fat on abdominal wall, normal pancreas and abdominal aorta were delineated, the CT values and standard deviation (SD) of each ROI were measured and recorded, and the pancreatic signal-to-noise ratio (SNR) and contrast-to-noise ratio (SNR) of each energy image were calculated. The objective index and subjective score of VMI(40-100keV) and PI (80kVp and 140kVp) with iodine (water) base map and VMI best CNR were compared between groups. The correlation between VMI(40-100keV) and PI(80, 140kVp) with iodine (water) base map and VMIbest CNR was analyzed by univariate regression.Results:In VMI(40-100keV) of normal pancreas, the highest SNR value was VMI best CNR and iodine (water) base map, and the highest CNR values were VMI 60keV and iodine (water) base map. There were significant differences on SNR and CNR values between different energy VMI and iodine (water) base map ( P<0.05). Among the four images of PI 80kVp, PI 140kVp, VMI best CNR and iodine (water) base map for pancreatic lesions, the SNR and CNR values of iodine (water) base map were the highest. The SNR and CNR values of VMI best CNR were higher than those of PI 80kVp, and the differences were statistically significant ( P<0.05). The lesion significance and edge sharpness score of iodine (water) base map was the highest, which was better than other groups; the lesion significance and edge sharpness score of VMI best CNR was better than PI 140kVp, and the differences were statistically significant ( P<0.05). The results of univariate regression analysis showed that the SNR values of PI 80kVp, PI 140kVp and VMI best CNR for pancreatic lesions were positively correlated with those of the iodine (water) base map ( P<0.05), the CNR values of PI 140kVp and VMI best CNR images were positively correlated with the iodine (water) base map ( P<0.05), and the SNR and CNR values of PI 140kVp were positively correlated with VMI best CNR ( P<0.05). Conclusions:VMI with different energy and iodine (water) base maps can be obtained by single source DECT enhanced scanning of pancreas related diseases. The VMI best CNR was the best among all VMIs, while the SNR and CNR values of iodine (water) base maps were the highest in all images. The VMI best CNR and iodine (water) base maps can improve the image quality of pancreas related diseases.

Objective To analyze the homology, biofilm-forming ability, and risk factors of prevalent A, B, C clones(carrying blaOXA-23 and blaOXA-51 genes mostly) of carbapenem-resistant Acinetobacter baumannii (CRAB) relative to carbapenemsusceptible Acinetobacter baumannii (CSAB). Methods A total of 87 prevalent A, B, C clones of CRAB and CSAB strains were collected from the First Affiliated Hospital of Chongqing Medical University. Multilocus sequence typing (MLST) was used for homologyanalysis of clone A, B, C strains. Biofilm-forming ability of CRAB and CSAB was measured quantitatively via crystal violet staining. Results Clone A was measured to be homologous type of ST238, while clones B and C were ST238 type. In general, CRAB prevalent clones showed weaker biofilm-forming ability than CSAB strains (0.470±0.301 versus 0.913±0.626, P＜0.05). CRAB clones A, B, and C varied in ability of biofilm formation. Clone A had comparative biofilm-forming ability to clone C (P=0.432). Both clone A and C were weaker than clone B in biofilm-forming ability (both P＜0.001). Biofilm-forming ability was not associated with blaOXA-23 or blaOXA-51 genes in CRAB strains (both P＞0.05). Conclusions Prevalent CRAB clone A, B, C are derived from the same origin. We are the first to report the prevalence of ST238 and the homologous types in a hospital. Biofilm-forming ability is negatively correlated with carbapenem resistance of Acinetobacter baumannii, which suggests that clone prevalence is mainly related to antibiotic resistance acquisition and antibiotic selective pressure. Biofilm-forming ability varies with the prevalent CRAB clone. The wide spread of clone B is of concern.