The S100 protein family is a key component of damage-associated molecular patterns(DAMP), which play a vital role in regulating inflammation in the body's innate immune response. S100A8/S100A9 proteins play a wide range of antibacterial and anti-infective functions in many diseases, and promote the occurrence and development of the body's immune and inflammatory responses. In various retinal degenerative diseases, S100A8/S100A9 proteins are significantly upregulated at the transcription and translation stages, promoting the activation of inflammatory factors in ocular tissues, the activation and recruitment of immune cells such as macrophages and neutrophils, and the occurrence and development of ocular inflammation. This review aimsat explaining the biological functions of S100A8/S100A9 proteins and their roles and possible mechanisms in retinal degenerative diseases such as diabetic retinopathy, age-related macular degeneration and ischemic retinopathy.

Objective:To analyze the pathogen distribution and prognostic risk factors of catheter-related bloodstream infection (CRBSI) in patients with maintenance hemodialysis (MHD) during non-hospitalization.Methods:A retrospective comparative study was conducted. Thirty-four patients of MHD with semi-permanent catheter admitted to the department of nephrology of Gansu Provincial Hospital from January 2020 to May 2023 due to CRBSI during non-hospitalization were enrolled. The distribution characteristics of pathogens causing CRBSI in MHD patients during non-hospital period were analyzed. All patients were actively given anti-infection treatment after admission. The general data, laboratory indicators and prognosis during hospitalization were collected through the electronic medical record system. Patients were divided into poor prognosis group (14 cases) and good prognosis group (20 cases) according to the treatment results during hospitalization. Univariate and binary Logistic regression were used to analyze the risk factors affecting the prognosis of patients, and receiver operator characteristic curve (ROC curve) was drawn to evaluate its predictive value for prognosis.Results:A total of 28 pathogenic bacteria were isolated from 34 patients, of which 25 were Gram-positive, Staphylococcus was the most common pathogen, accounting for 82.15% of the total, and 16 strains of Staphylococcus aureus (57.15%), including 6 methicillin-resistant Staphylococcus aureus (MRSA, 21.43%). There were 7 strains of Staphylococcus epidermidis (25.00%), including 3 strains of methicillin-resistant Staphylococcus epidermidis (MRSE, 10.71%). There were 3 strains of Gram-negative bacteria, 1 strain each of Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii. Univariate analysis showed that the fever duration of MHD patients with CRBSI in the poor prognosis group was significantly longer than that in the good prognosis group [days: 8.50 (3.75, 45.00) vs. 2.50 (1.00, 4.75), P < 0.01], serum erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and random blood glucose (GLU) were significantly higher than those in the good prognosis group [ESR (mm/1 h): 82.36±24.98 vs. 56.95±35.65, CRP (mg/L): 123.45±74.10 vs. 67.35±55.22, GLU (mmol/L): 8.74±3.66 vs. 6.42±1.95, all P < 0.05]. Binary Logistic regression analysis showed that serum CRP was an independent risk factor for poor prognosis in MHD patients with CRBSI [odds ratio ( OR) = 1.020, 95% confidence interval (95% CI) was 1.002-1.038, P = 0.025]. ROC curve analysis showed that the area under the curve (AUC) of serum CRP in predicting poor prognosis of MHD patients with CRBSI was 0.711; when the optimal cut-off value was 104.65 mg/L, the sensitivity was 64.3% and the specificity was 85.0%, indicating that it has good predictive value. Conclusions:Gram-positive bacteria are the main pathogens of CRBSI in MHD patients during non-hospital period. The poor prognosis is mainly related to the high level of serum CRP. Serum CRP level can effectively screen the high-risk group of MHD patients with CRBSI with poor prognosis.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective We propose a low-dose CT reconstruction method using partial differential equation (PDE) denoising under high-dimensional constraints. Methods The projection data were mapped into a high-dimensional space to construct a high-dimensional representation of the data, which were updated by moving the points in the high-dimensional space. The data were denoised using partial differential equations and the CT image was reconstructed using the FBP algorithm. Results Compared with those by FBP, PWLS-QM and TGV-WLS methods, the relative root mean square error of the Shepp-Logan image reconstructed by the proposed method were reduced by 68.87％, 50.15％ and 27.36％, the structural similarity values were increased by 23.50％, 8.83％ and 1.62％, and the feature similarity values were increased by 17.30％, 2.71％ and 2.82％, respectively. For clinical image reconstruction, the proposed method, as compared with FBP, PWLS-QM and TGV-WLS methods, resulted in reduction of the relative root mean square error by 42.09％, 31.04％and 21.93％, increased the structural similarity values by 18.33％, 13.45％ and 4.63％, and increased the feature similarity values by 3.13％, 1.46％ and 1.10％, respectively. Conclusion The new method can effectively reduce the streak artifacts and noises while maintaining the spatial resolution in reconstructed low-dose CT images.

Objective We propose a low-dose CT reconstruction method using partial differential equation (PDE) denoising under high-dimensional constraints. Methods The projection data were mapped into a high-dimensional space to construct a high-dimensional representation of the data, which were updated by moving the points in the high-dimensional space. The data were denoised using partial differential equations and the CT image was reconstructed using the FBP algorithm. Results Compared with those by FBP, PWLS-QM and TGV-WLS methods, the relative root mean square error of the Shepp-Logan image reconstructed by the proposed method were reduced by 68.87％, 50.15％ and 27.36％, the structural similarity values were increased by 23.50％, 8.83％ and 1.62％, and the feature similarity values were increased by 17.30％, 2.71％ and 2.82％, respectively. For clinical image reconstruction, the proposed method, as compared with FBP, PWLS-QM and TGV-WLS methods, resulted in reduction of the relative root mean square error by 42.09％, 31.04％and 21.93％, increased the structural similarity values by 18.33％, 13.45％ and 4.63％, and increased the feature similarity values by 3.13％, 1.46％ and 1.10％, respectively. Conclusion The new method can effectively reduce the streak artifacts and noises while maintaining the spatial resolution in reconstructed low-dose CT images.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective To compare the efficacy of ultrasound-guided microwave ablation versus thyroidectomy in the treatment of benign thyroid nodules (BTN) and to explore the influencing factors of prognosis. Methods A total of 282 BTN patients were enrolled and divided into ablation group (treated with ultrasound-guided microwave ablation, n=172) and resection group (treated with thyroidectomy, n=110) based on treatment methods. Perioperative indicators and thyroid function indices before and after surgery were compared between the two groups. Patients were followed up for 1 year and divided into good prognosis group [volume reduction rate (VRR)≥80%, n=210] and a poor prognosis group (VRR < 80%, n=72) based on the VRR. Factors influencing the prognosis of BTN patients were analyzed. Results The ablation group had shorter operative time and hospital stay, less intraoperative blood loss, and lower postoperative Visual Analogue Scale (VAS) scores compared to the resection group (P < 0.05). One month after surgery, serum thyrotropin (TSH) levels were higher, while free triiodothyronine (FT3) and free thyroxine (FT4) levels were lower than preoperative levels in both groups, however, TSH level was lower, and FT3 and FT4 levels were higher in the ablation group compared to the resection group (P < 0.05). Univariate analysis showed that preoperative TSH levels, the proportion of solid nodules, and the proportion of nodules in the risk zone were lower, while preoperative FT4 levels were higher in the good prognosis group compared to the poor prognosis group (P < 0.05). Binary Logistic regression analysis revealed that nodule type, nodule location, preoperative TSH, and preoperative FT4 were all influencing factors for the prognosis of BTN patients (P < 0.05). Conclusion Compared to thyroidectomy, ultrasound-guided microwave ablation for BTN offers advantages such as less intraoperative blood loss, milder postoperative pain, shorter operative time and hospital stay, and less damage to thyroid function. Preoperative TSH and FT4 levels, nodule type, and nodule location are closely related to the prognosis of BTN patients and should be given attention in clinical practice.

Objective:To investigate CT manifestations of perivascular epithelioid cell tumors.Methods:The multi-slice spiral CT manifestations in 11 patients with perivascular epithelioid cell tumors which were pathologically confirmed in the First Affiliated Hospital of Shantou University Medical College between October 2012 and August 2021 were retrospectively analyzed.Results:Perivascular epithelioid cell tumors were located in the kidney of eight patients, in the right lobe of the liver of two patients, and in the descending colon of one patient. The largest tumor, approximately 20.0 cm × 26.0 cm × 11.0 cm, was located in the kidney. The smallest tumor, 2.4 cm × 2.6 cm × 3.4 cm, was located in the colon. CT plain scans showed uniform density without bleeding, calcification, or fat in two patients, and non-uniform density with fatty change in two patients. Contrast-enhanced CT images showed non-uniform enhancement in the arterial phase in 10 patients and uniform enhancement in one patient. Contrast-enhanced CT images showed decreased degrees of enhancement of the lesions in 11 patients from the portal venous phase to the delayed phase and dilated and tortuous vascular shadows in 11 patients.Conclusion:The multi-slice spiral CT manifestations of perivascular epithelioid cell tumors are characteristic and the multi-slice spiral CT is of value for the diagnosis of perivascular epithelioid cell tumors.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical bacterial isolates from bloodstream infections in China in 2021.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2021 to December 2021. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 11 013 bacterial strains were collected from 51 hospitals, of which 2 782 (25.3%) were Gram-positive bacteria and 8 231 (74.7%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.6%), Klebsiella pneumoniae (18.9%), Staphylococcus aureus (9.8%), coagulase-negative Staphylococci (6.3%), Pseudomonas aeruginosa (3.6%), Enterococcus faecium (3.6%), Acinetobacter baumannii (2.8%), Enterococcus faecalis (2.7%), Enterobacter cloacae (2.5%) and Klebsiella spp (2.1%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 25.3% and 76.8%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci was detected; more than 95.0% of Staphylococcus aureus were sensitive to ceftobiprole. No vancomycin-resistant Enterococci strains were detected. The rates of extended spectrum B-lactamase (ESBL)-producing isolated in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 49.6%, 25.5% and 39.0%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.2% and 15.8%, respectively; 7.9% of carbapenem-resistant Klebsiella pneumoniae was resistant to ceftazidime/avibactam combination. Ceftobiprole demonstrated excellent activity against non-ESBL-producing Escherichia coli and Klebsiella pneumoniae. Aztreonam/avibactam was highly active against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii (5.5% and 4.5%). The prevalence of carbapenem-resistance in Pseudomonas aeruginosa was 18.9%. Conclusions:The BRICS surveillance results in 2021 shows that the main pathogens of blood stream infection in China are gram-negative bacteria, in which Escherichia coli is the most common. The MRSA incidence shows a further decreasing trend in China and the overall prevalence of vancomycin-resistant Enterococci is low. The prevalence of Carbapenem-resistant Klebsiella pneumoniae is still on a high level, but the trend is downwards.

Clinical undergraduates generally have the following problems during their radiology internship: short internship period, low motivation, teachers using traditional teaching mode, and insufficient hardware and software facilities for image reading. In this study, RadiAnt DICOM Viewer and case-based learning (CBL) model were applied in online practice teaching for clinical undergraduates in the radiology department, which achieved good results. The results showed that the clinical undergraduates had a pass rate of 91.18% (124/136) in the image reading quiz and a mean score of (85.71±10.99) in the in-class quiz, with a pass rate of 91.91% (125/136). The satisfaction survey showed that 84.56% (115/136) of the students were more satisfied with the application of RadiAnt DICOM Viewer in image reading teaching; 80.88% (110/136) of the students expressed more interest in radiology after this training course; 90.44% (123/136) of the students thought that online practice teaching of radiology is feasible.