BACKGROUND:Magnetic resonance imaging is the gold standard for the diagnosis of osteonecrosis of femoral head,and previous methods of predicting osteonecrosis of femoral head collapse based on magnetic resonance images mostly require the combined assessment of coronal and sagittal images.However,osteonecrosis of femoral head tends to occur bilaterally,most hospitals perform bilateral hip magnetic resonance imaging scans during clinical examinations,but the bilateral hip scans can only view coronal and cross-sectional images,and it is difficult to obtain sagittal images,which affects the assessment of the risk of collapse.Therefore,it is of clinical value to establish a method to assess the risk of early osteonecrosis of femoral head collapse by applying the images that can be obtained after bilateral hip magnetic resonance scanning. OBJECTIVE:To establish a method of applying coronal and cross-sectional images of bilateral hip magnetic resonance imaging to assess the risk of osteonecrosis of femoral head collapse. METHODS:The medical records of 111 patients(181 hips)with early-stage osteonecrosis of femoral head diagnosed at the outpatient clinic of Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2017 to October 2019 were retrospectively analyzed.They were categorized into collapsed and non-collapsed groups according to the femoral head collapse at the final follow-up,with 69 hips in the collapsed group and 112 hips in the non-collapsed group.The angle of necrotic range on the images of median coronal plane,transverse plane or one level above and below it was measured on the magnetic resonance imaging system.The sum of the two angles of necrotic angle on the coronal and transverse planes was used as the combined necrotic angle.The average of the three combined necrotic angles of each hip was taken to get the average combined necrotic angle of each hip.Finally,the correlation between the three combined necrotic angles and the average combined necrotic angle with the collapse of osteonecrosis of femoral head was analyzed,and the specificity and sensitivity of the four combined necrotic angles in predicting collapse were evaluated by using receiver operating characteristic curves. RESULTS AND CONCLUSION:(1)Totally 69 hips(38.1%)had femoral head collapse at the last follow-up and were included in the collapsed group;112 hips(61.9%)did not have progression of collapse and were included in the non-collapsed group.(2)The difference between the collapsed group and the non-collapsed group in terms of Association Research Circulation Osseous(ARCO)stage was significant(P<0.001).The difference in age,body mass index,follow-up time,gender distribution,side of onset,and causative factors was not significant(P>0.05).(3)The results of independent samples t-test suggested that all four combined necrotic angles were significantly correlated with collapse(P<0.000 1);and the differences in combined necrotic angles between the collapsed group and the non-collapsed group of ARCO stage I and the two groups of ARCO stage II were all significant(P<0.000 1).(4)In the analysis of the receiver operating characteristic,the area under the curve of the average combined necrotic angle was greater than that of the combined necrotic angle on the lower level of the median,the middle level,and the upper level of the median.(5)The average combined necrotic angle had a higher accuracy in the prediction of collapse than the lower level of the median,the middle level,and the upper level of the combined necrotic angle.(6)It is concluded that the accuracy of the average combined necrotic angle in predicting the risk of osteonecrosis of femoral head collapse is higher,and the clinical practicability is stronger,so we can consider using this method to predict the risk of osteonecrosis of femoral head collapse.

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.

BACKGROUND:For non-traumatic osteonecrosis of the femoral head,if the femoral head collapses,it will have a great impact on the normal life of the patients.Thus,it is necessary to use an appropriate way to evaluate the risk of femoral head collapse and then to take targeted measures to delay the process of femoral head collapse. OBJECTIVE:To analyze the natural course of early osteonecrosis of the femoral head(without collapse)under different locations of necrotic lesions. METHODS:121 patients(191 hips)with early non-traumatic osteonecrosis of the femoral head who were treated in the Outpatient Department of Honghui Hospital Affiliated to Xi'an Jiaotong University from October 2016 to October 2017 were enrolled in this study.The clinical data of all patients were followed up for 5 years to observe the collapse of osteonecrosis of the femoral head and the risk coefficient of femoral head collapse among different JIC types.The collapse rate of osteonecrosis of the femoral head was calculated during the follow-up. RESULTS AND CONCLUSION:(1)A total of 191 hips were included in this study.The femoral head collapsed in 86 hips during follow-up,with a total collapse rate of 45.0%.Among the influencing factors,age,ARCO stage and JIC classification were the main influencing factors of femoral head collapse(P<0.05),but body mass index,sex,incidence side and pathogenic factors were not the main influencing factors(P>0.05).(2)Among 191 hips,in JIC classification,the total collapse rates of type A,type B,type C1 and type C2 were 11.1%(2/18),30.2%(16/53),52.4%(43/82),and 65.8%(25/38),respectively.There were significant differences in the total collapse rate of the femoral head among all types(P<0.05).The collapse risk results showed that the collapse risk of type B,type C1 and type C2 was 2.41,5.22 and 7.89 times higher than that of type A,respectively.(3)Both JIC classification and ARCO stage were correlated with femoral head collapse(P<0.01).There was no significant difference in the collapse rate of the femoral head among all JIC types in ARCO I stage hips(P>0.05).In the hips with ARCO II stage,the collapse rates of the femoral head of JIC types A,B,C1 and C2 were 1.2%,19.5%,50.0%and 29.3%,respectively,and there were significant differences in the collapse rates among different types(P<0.05).(4)During follow-up,the collapse rates of the femoral head in the first to fifth years were 29.3%,7.9%,4.7%,2.6%and 0.5%,respectively.(5)Results showed that for early non-traumatic osteonecrosis of the femoral head,the risk of collapse of osteonecrosis of the femoral head is high within one year,and the location of the focus of osteonecrosis affects the risk of collapse of the femoral head.The effect of the location of the focus on the prognosis of the disease should be considered in clinical treatment.

Objective To determine the effects of ciprofol and propofol on hemodynamics and cardiac work were determined by hemodynamic monitoring,so as to provide reference for anesthesia induction in car-diac surgery.Methods A total of 90 patients scheduled for mitral valve replacement under cardiopulmonary bypass from June 2022 to June 2023 were randomly divided into two groups:the ciprofol group (group P,n=45) and the propofol group (group B,n=45).The heart rate (HR),oxygen saturation (SpO2),index of con-sciousness (ICO1),mean arterial pressure (MAP),central venous pressure (CVP),stroke volume (SV),car-diac output (CO),systemic vascular resistance (SVR),cardiac cycle efficiency (CCE),stroke volume variation (SVV),maximum pressure gradient reflecting myocardial contractility (dp/dt) were recorded before adminis-tration (T0) and five min after administration (T1).Results In group P,ICO1,MAP,SV,CO,and SVR at T1 were lower than those at T0,and CCE was higher than that at T0 (P<0.01,P<0.05).In group B,ICO1, MAP,CVP,SV,CO,SVR,CCE,SVV,dp/dt at T1 were significantly lower than those at T0 (P<0.01,P<0.05).There was no statistically significant difference in HR,SpO2,ICO1,MAP,CVP and hemodynamic indi-cators between group B and group P at T0 (P>0.05).There was no statistically significant difference in HR, SpO2,ICO1,CVP and SVV between group B and group P at T1 (P>0.05).MAP,SV,CO,SVR,CCE and dp/dt at T1 in group P were higher than those in group B (P<0.05).Conclusion Ciprofol can better maintain hemodynamic stability and reduce cardiac impairment during the induction phase of mitral valve replacement surgery under cardiopulmonary bypass.

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.

Non-pharmaceutical interventions (NPIs) implemented during the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) epidemic have been proven to be effective in blocking the spread of the epidemic.While reducing SARS-CoV-2 transmission, NPIs also reduce children exposure to other pathogens, leading to a decline in the incidence of many viral and bacterial infections.The reduction in contact with viruses and bacteria and the delay or interruption of routine immunization during SARS-CoV-2 epidemic have resulted in insufficient immune stimulation of pathogens on the population, leading to an increase in susceptible populations and a decline in herd immunity, forming the immune debt during SARS-CoV-2 epidemic.After reducing or lifting NPIs, the incidence of some viral or bacterial infectious diseases was significantly higher than pre-epidemic.In this review, the definition, source, impact and strategies of immune debt during epidemic period were expounded, inorder to improve clinicians′ attention and understanding of immune debt and optimize the prevention of children′s infectious diseases.

Humans ; Blood Pressure/physiology* ; Cohort Studies ; Patient Discharge ; Ischemic Stroke ; Stroke ; Brain Ischemia ; Diabetes Mellitus ; Hypertension

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.

Objective:To understand the incubation periods of infections of Omicron variants BA.2 and BF.7 in two COVID-19 epidemics and related factors in Beijing and provide basic parameters for the establishment of 2019-nCoV dynamic transmission model.Methods:The COVID-19 cases with specific exposure time and onset time in the Omicron variant BA.2 infection epidemic in April 2022 and in the Omicron variant BF.7 infection epidemic in October 2022 in Beijing were included in the analysis. The rank-sum test was conducted to estimate the differences in the incubation period between two types of infections. The incubation period distribution of the Omicron variant infection was fitted by using Weibull, Gamma and lognormal distributions. Multivariate analysis of variance was conducted to assess the effects of age, sex, variant type and vaccination status on the incubation periods.Results:A total of 64 cases of variant BA.2 infection and 58 cases of variant BF.7 infection were included. The M( Q1,Q3) of the incubation period was 3.00 (3.00, 4.00) days for BA.2 infection and 3.00 (2.00, 3.25) days for BF.7 infection. The lognormal distribution was the best fit. Multivariate analysis of variance showed that there were some differences in the incubation periods between two types of infections of Omicron variants, and the incubation period of variant BF.7 infection was shorter than that of variant BA.2 infection. Conclusion:Omicron variant BF.7 infection had shorter incubation period compared with Omicron variant BA.2 infection.