Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. 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 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective To observe CT and MRI manifestations of gastritis cystica profunda(GCP).Methods Seventeen patients with GCP confirmed by operation or biopsy pathology were enrolled,and lesions'CT and MRI manifestations were observed.Results Among 17 cases,16 cases(16/17,94.12％)were found with single lesion and 1(1/17,5.88％)with diffuse multiple lesions.The lesion located in the fundus of stomach in 5 cases(5/17,29.41％),in the body of stomach in 4 cases(4/17,23.53％),in the cardia and antrum of stomach each in 3 cases(3/17,17.65％)and in the pylorus in 1 case(1/17,5.88％),while 1 case(1/17,5.88％)was found with diffused multiple lesions within stomach.Non-enhance CT showed local thickening of gastric wall in 10 cases(10/17,58.82％),all were isodensities,and the mucosa uniformly enhanced in contrast enhance CT(CECT).Predominately cystic lesion in 5 cases(5/17,29.41％)presented as submucosal cystic protrusions,and grew into the stomach cavity with circular or oblong low density in non-enhanced CT,while sandwich enhancement of mucosa was observed in CECT.Among these 5 cases(5/17,29.41％),MRI showed lesion confined to the submucosa with low signal on T1WI and high signal on T2WI,while diffusion weighted imaging showed unrestricted diffusion,and the enhancement pattern was consistent with that of CT in 2 cases.In other 2 cases(2/17,11.77％)with cystic-solid lesion,non-enhanced CT showed soft tissue density,while CECT showed lump-like stratified enhancement.Conclusion CT and MRI manifestations of GCP had certain characteristics.

Objective To observe CT and MRI manifestations of gastritis cystica profunda(GCP).Methods Seventeen patients with GCP confirmed by operation or biopsy pathology were enrolled,and lesions'CT and MRI manifestations were observed.Results Among 17 cases,16 cases(16/17,94.12％)were found with single lesion and 1(1/17,5.88％)with diffuse multiple lesions.The lesion located in the fundus of stomach in 5 cases(5/17,29.41％),in the body of stomach in 4 cases(4/17,23.53％),in the cardia and antrum of stomach each in 3 cases(3/17,17.65％)and in the pylorus in 1 case(1/17,5.88％),while 1 case(1/17,5.88％)was found with diffused multiple lesions within stomach.Non-enhance CT showed local thickening of gastric wall in 10 cases(10/17,58.82％),all were isodensities,and the mucosa uniformly enhanced in contrast enhance CT(CECT).Predominately cystic lesion in 5 cases(5/17,29.41％)presented as submucosal cystic protrusions,and grew into the stomach cavity with circular or oblong low density in non-enhanced CT,while sandwich enhancement of mucosa was observed in CECT.Among these 5 cases(5/17,29.41％),MRI showed lesion confined to the submucosa with low signal on T1WI and high signal on T2WI,while diffusion weighted imaging showed unrestricted diffusion,and the enhancement pattern was consistent with that of CT in 2 cases.In other 2 cases(2/17,11.77％)with cystic-solid lesion,non-enhanced CT showed soft tissue density,while CECT showed lump-like stratified enhancement.Conclusion CT and MRI manifestations of GCP had certain characteristics.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. 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 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

BACKGROUND:The pituitary gland is an important endocrine organ in the body.Certain diseases can cause damage to the pituitary gland,such as pituitary adenoma and abnormal hormone secretion.Pituitary stem cells,due to their self-renewal and multi-directional differentiation potential,are expected to become a new therapeutic approach for repairing damaged pituitary glands. OBJECTIVE:To isolate and culture pituitary stem cells using the suspension cell ball culture method and identify their proliferation and differentiation ability. METHODS:Pituitary stem cells were isolated and cultured from the pituitary gland of newborn New Zealand white rabbits using the suspension cell ball culture method,and their morphological characteristics were observed.Immunofluorescence cytochemistry was used to detect the expression of pituitary stem cell markers SOX2 and Nestin.EdU labeling method was utilized to detect the proliferative ability of pituitary stem cells.After adherent and induced differentiation,the hormone levels in the culture medium were detected by ELISA. RESULTS AND CONCLUSION:Pituitary stem cell spheres could be successfully isolated by the suspension cell ball culture method,with strong proliferative ability.Positive expression of stem cell-specific markers SOX2 and Nestin was found in the cultured cells.After induction and differentiation,adrenocorticotropic hormone,thyroid hormone,growth hormone,luteinizing hormone,follicle-stimulating hormone,and prolactin levels significantly increased in the medium(P<0.001),with strong differentiation ability.

BACKGROUND:There is currently no anatomic locking plate suitable for the anteromedial platform,so the medial locking plate of the tibial plateau is usually placed forward to fix anteromedial compression fractures caused by hyperextension varus injury.Due to the inability of the locking screw to achieve vertical fixation of the fracture line,coupled with the influence of the patellar ligament,the clinical results are still unsatisfactory. OBJECTIVE:To compare the biomechanical performance of a new type of plate with traditional internal fixation methods in treating hyperextension varus tibial plateau fractures through finite element analysis. METHODS:CT data of 20 cases of hyperextension varus tibial plateau fractures were collected,and their morphological characteristics,such as medial posterior tibial slope,the medial articular fracture angle,surface area,and anterior cortical height were measured.A 24-year-old male volunteer with a height of 175 cm and a weight of 65 kg was selected,and his tibial CT data were imported into Mimics 21.0 software to generate a 3D model.Then,internal fixation models were imported into SolidWorks 2017 software.New type of plate,medial locking plate,posterior medial locking plate,and 6.5 mm hollow screws fixed data models were established based on the measured morphological data.Ansys 17.0 software was used to load stress on the four fixation models and compare their biomechanical performance. RESULTS AND CONCLUSION:(1)With the increase of axial load,the peak stresses of different internal fixation models approximately increased proportionally.At 500 N,the peak stress values were as follows:screw group(6.973 7 MPa)

Humans ; Asthma/drug therapy* ; Biological Therapy

Objective:To investigate the feasibility and clinical efficacy of percutaneous screw fixation for acetabular anterior column fracture with laser-assisted axial fluoroscopy.Methods:Data of 20 patients (22 sided) with acetabular anterior column fracture treated by percutaneous screw fixation with laser-assisted axial fluoroscopy from January 2017 to December 2018 were retrospectively analyzed. There were 11 males and 9 females with an average of 42.1±3.2 years (range, 24-68 years). There were 7 cases of unilateral acetabular anterior column fracture, 2 cases of bilateral acetabular anterior column fracture (4 sides), 7 cases of anterior column with ipsilateral sacral fracture, and 4 cases of anterior column with sacroiliac joint injury. There were 3 hips of Area I, 6 Area II, 13 Area III of acetabular anterior column fractures according to Nakatani partition. The time from injury to surgery was 5 days (range, 3-11 days). All patients with acetabular anterior column fractures were fixed by percutaneous screw fixation with laser-assisted axial fluoroscopy, and patients with sacral fracture or sacroiliac joint injury were fixed by percutaneous sacroiliac screws with Starr frame-assisted reduction. The time of operation, the number of intraoperative fluoroscopy and the amount of intraoperative bleeding were recorded. Matta scoring criteria were used to assess fracture reduction quality, and hip function was assessed at the last follow-up according to the modified Merle D' Aubigné and Postel scoring system.Results:The average operative time was 22±10 min (range, 20-40 min) with an average times of intraoperative fluoroscopy of 30±8 times (range, 21-45 times), and the amount of intraoperative blood loss was 20±5 ml (range, 10-40 ml). 20 patients were followed up after operation for a period of 14±3.1 months (range, 12-18 months). The quality of postoperative fracture reduction was assessed according to the Matta acetabular fracture reduction criteria: anatomical reduction in 18 hips, satisfactory reduction in 2 hips, unsatisfactory reduction in 2 hips, with an excellent and good rate of 91% (20/22). The fracture healing time was 13±2.2 weeks (range, 11-16 weeks). At the lastest follow-up, hip function was assessed according to the modified Merle D' Aubigné and Postel scoring system: excellent 18, good 3, fair 1, and the satisfactory rate was 95%(21/22). No major neurological, vascular injury, wound infection and ectopic ossification were found during follow-up.Conclusion:Using laser-assisted axial fluoroscopy percutaneous screw to treat acetabular anterior column fracture, the operation is simple. And there is low risk to damage important blood vessels and nerves. This method can shorten the operation time of acetabular anterior column fracture, reduce the amount of blood loss during the operation, and the outcome is satisfactory.