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.

AIM:To evaluate the clinical efficacy and safety of pneumoperitoneum-free single-hole endoscopy combined with ropivacaine local infiltra-tion anesthesia in pregnancy with ovarian tumor.METHODS:Twenty-eight pregnant women with ovarian tumor were randomly divided into two groups:observation group(n=16)and control group(n=12).The first time out of bed,ventilation time,postoperative hospital stay,non-invasive blood pressure,heart rate(HR),respiratory fre-quency(RR)and blood oxygen saturation(SpO2)were compared between the two groups.Pain score,Ramsay sedation score,SAS anxiety score,postoperative complications,patient satisfaction and recovery quality scale QoR15 were evaluated at 6,24 and 48 hours after operation.RESULTS:There was no significant difference in postopera-tive hospital stay,Ramsay score,RR,SpO2 and the incidence of complications between the two groups(P>0.05),but the time of getting out of bed and ventilation time were shortened,the scores of non-invasive blood pressure,HR,pain and anxiety in the observation group were lower than those in the control group,and the scores of patient satisfac-tion and QoR15 in the observation group were bet-ter than those in the control group(P<0.05).CON-CLUSION:The application of pneumoperitoneum-free single-hole endoscope combined with ropiva-caine local infiltration anesthesia in pregnancy with ovarian tumor can reach satisfactory clinical re-sults,including reducing postoperative pain and anxiety,which is worth popularizing.

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.

Clinical data of 15 primary central nervous system lymphoma (PCNSL) children aged ≤18 years admitted to our hospital between May 2013 to May 2023 were retrospectively analyzed. Our goal was to summarize the clinical features of children and investigate the therapeutic effect of a high-dose methotrexate (HD-MTX) based chemotherapy regimen on this disease. The male-to-female ratio was 2.7∶1, and the median age was 7.2 (2.3-16.4) years at diagnosis. The initial clinical symptoms were primarily cranial hypertension, with imaging findings revealing multiple lesions. Pediatric PCNSL with normal immune function has a favorable prognosis with HD-MTX-based chemotherapy. Patients with a stable disease can be treated with minimal or no maintenance. HD-MTX-based chemotherapy remains effective when the disease progresses or recurs after an initial course of non-HD-MTX-based chemotherapy.

Objective:To analyze the factors affecting delayed chemotherapy in children with Burkitt lymphoma (BL) and their influence on prognosis.Methods:Retrospective cohort study. Clinical data of 591 children aged ≤18 years with BL from May 2017 to December 2022 in China Net Childhood Lymphoma (CNCL) was collected. The patients were treated according to the protocol CNCL-BL-2017. According to the clinical characteristics, therapeutic regimen was divided into group A, group B and group C .Based on whether the total chemotherapy time was delayed, patients were divided into two groups: the delayed chemotherapy group and the non-delayed chemotherapy group. Based on the total delayed time of chemotherapy, patients in group C were divided into non-delayed chemotherapy group, 1-7 days delayed group and more than 7 days delayed group. Relationships between delayed chemotherapy and gender, age, tumor lysis syndrome before chemotherapy, bone marrow involvement, disease group (B/C group), serum lactate dehydrogenase (LDH) > 4 times than normal, grade Ⅲ-Ⅳ myelosuppression after chemotherapy, minimal residual disease in the interim assessment, and severe infection (including severe pneumonia, sepsis, meningitis, chickenpox, etc.) were analyzed. Logistic analysis was used to identify the relevant factors. Kaplan-Meier method was used to analyze the patients' survival information. Log-Rank was used for comparison between groups.Results:Among 591 patients, 504 were males and 87 were females, the follow-up time was 34.8 (18.6,50.1) months. The 3-year overall survival (OS) rate was (92.5±1.1)%,and the 3-year event-free survival (EFS) rate was (90.5±1.2)%. Seventy-three (12.4%) patients were in delayed chemotherapy group and 518 (87.6%) patients were in non-delayed chemotherapy group. The reasons for chemotherapy delay included 72 cases (98.6%) of severe infection, 65 cases (89.0%) of bone marrow suppression, 35 cases (47.9%) of organ dysfunction, 22 cases (30.1%) of tumor lysis syndrome,etc. There were 7 cases of chemotherapy delay in group B, which were seen in COPADM (vincristine+cyclophosphamide+prednisone+daunorubicin+methotrexate+intrathecal injection,4 cases) and CYM (methotrexate+cytarabine+intrathecal injection,3 cases) stages. There were 66 cases of chemotherapy delay in group C, which were common in COPADM (28 cases) and CYVE 1 (low dose cytarabine+high dose cytarabine+etoposide+methotrexate, 12 cases) stages. Multinomial Logistic regression analysis showed that the age over 10 years old ( OR=0.54,95% CI 0.30-0.93), tumor lysis syndrome before chemotherapy ( OR=0.48,95% CI 0.27-0.84) and grade Ⅲ-Ⅳ myelosuppression after chemotherapy ( OR=0.55,95% CI 0.33-0.91)were independent risk factors for chemotherapy delay.The 3-year OS rate and the 3-year EFS rate of children with Burkitt lymphoma in the delayed chemotherapy group were lower than those in the non-delayed chemotherapy group ((79.4±4.9)% vs. (94.2±1.1)%, (80.2±4.8)% vs. (92.0±1.2)%,both P<0.05). The 3-year OS rate of the group C with chemotherapy delay >7 days (42 cases) was lower than that of the group with chemotherapy delay of 1-7 days (22 cases) and the non-delay group (399 cases) ((76.7±6.9)% vs. (81.8±8.2)% vs. (92.7±1.3)%, P=0.002).The 3-year OS rate of the chemotherapy delay group (9 cases) in the COP (vincristine+cyclophosphamide+prednisone) phase was lower than that of the non-chemotherapy delay group (454 cases) ((66.7±15.7)% vs. (91.3±1.4)%, P=0.005). Similarly, the 3-year OS rate of the chemotherapy delay group (11 cases) in the COPADM1 phase was lower than that of the non-chemotherapy delay group (452 cases) ((63.6±14.5)% vs. (91.5±1.3)%, P=0.001). Conclusions:The delayed chemotherapy was related to the age over 10 years old, tumor lysis syndrome before chemotherapy and grade Ⅲ-Ⅳ myelosuppression after chemotherapy in pediatric BL. There is a significant relationship between delayed chemotherapy and prognosis of BL in children.

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 explore the cost-effectiveness and cost-benefit of chronic obstructive pulmonary disease (COPD) screening and intervention based on family doctor contract services.Methods:From January 2023 to October 2023, using purposive sampling and a cross-sectional survey method, 1 040 individuals aged 60 to 75 years who underwent physical examinations at community health service centers in Shanghai Minhang district were selected as research subjects. The subjects were divided into a control group ( n=532) and a study group ( n=508). The control group received conventional community health education and participated in a COPD screening and intervention program provided by the examination center. The study group received COPD screening and intervention provided by contracted family doctors under a tightly integrated medical consortium. The screening content for both groups included initial and follow-up risk assessment questionnaires, pulmonary function tests, bronchodilator tests, and CT scans. A comparative analysis was conducted on the screening compliance rate, positive rate, and cost-effectiveness and cost-benefit between the two groups. Results:A total of 251 individuals at high risk for COPD and confirmed COPD patients were identified through initial and re-screening in both groups, accounting for 24.13% of the subjects, including 222 individuals at high risk (21.35%) and 29 confirmed patients (2.79%). The study group had significantly higher compliance rates in questionnaire-based initial screening, questionnaire-based re-screening+pulmonary function tests, bronchodilator experiments, diagnosis, and subsequent CT scans than the control group ( χ2=33.563, 41.425, 24.842, 17.363, all P<0.05).There were significant higher proportions of high-risk individuals and patients identified through screening in the study group than those in the control group ( χ2=44.880, all P<0.05). The study group had significantly higher positive rates of questionnaire-based initial screening, pulmonary function tests, bronchodilator experiments, and CT scans than the control group ( χ2=29.191, 11.313, 12.370, 4.429, all P<0.05). The overall costs of the screening in the control and study groups were 36 100 and 53 900 yuan, respectively. The cost of pulmonary function tests in the screening for the control and study groups was 1.44 million and 2.45 million yuan, respectively, accounting for 43.19% of the total cost, which was the highest proportion among all costs. The per capita cost for identifying one high-risk individual or patient with COPD was 358.46 Yuan, and the cost in study groups was significantly lower than that in the control group (322.75 vs. 429.45 yuan, χ2=20.396, P<0.05). The per capita net benefits and cost-benefit ratios for the overall subjects in the two groups were 0.37 million yuan and 43.50, respectively. The average net benefit of the study group and the control group was 0.49 million yuan and 0.26 million yuan respectively. The average net benefit of the study group was 0.23 million yuan higher than that of the control group. The cost-benefit ratio of the study group and the control group were 46.77 and 38.61, respectively. The cost-benefit ratio of the study group was 8.16 higher than that of the control group. Conclusion:The screening and intervention for COPD based on family doctor contract services have significant effectiveness, with a marked improvement in screening compliance and high cost-effectiveness, and can be used in community medical institutions with relatively sound family doctor and medical consortium services for targeted COPD screening.

Background::Cluster of differentiation 8 (CD8 T) cells play critical roles in eradicating human immunodeficiency virus (HIV)-1 infection, but little is known about the effects of T cells expressing CD8 at low levels (CD8 low) or high levels (CD8 high) on HIV-1 replication inhibition after HIV-1 invasion into individual. Methods::Nineteen patients who had been acutely infected with HIV-1 (AHI) and 20 patients with chronic infection (CHI) for ≥2 years were enrolled in this study to investigate the dynamics of the quantity, activation, and immune responses of CD3 +CD8 low T cells and their counterpart CD3 +CD8 high T cells at different stages of HIV-1 infection. Results::Compared with healthy donors, CD3 +CD8 low T cells expanded in HIV-1-infected individuals at different stages of infection. As HIV-1 infection progressed, CD3 +CD8 low T cells gradually decreased. Simultaneously, CD3 +CD8 high T cells was significantly reduced in the first month of AHI and then increased gradually as HIV-1 infection progressed. The classical activation of CD3 +CD8 low T cells was highest in the first month of AHI and then reduced as HIV-1 infection progressed and entered the chronic stage. Meanwhile, activated CD38 -HLA-DR +CD8 low T cells did not increase in the first month of AHI, and the number of these cells was inversely associated with viral load ( r = -0.664, P = 0.004) but positively associated with the CD4 T-cell count ( r = 0.586, P = 0.014). Increased programmed cell death protein 1 (PD-1) abundance on CD3 +CD8 low T cells was observed from the 1st month of AHI but did not continue to be enhanced, while a significant T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif (ITIM) domains (TIGIT) abundance increase was observed in the 12th month of infection. Furthermore, increased PD-1 and TIGIT abundance on CD3 +CD8 low T cells was associated with a low CD4 T-cell count (PD-1: r = -0.456, P = 0.043; TIGIT: r = -0.488, P = 0.029) in CHI. Nonetheless, the nonincrease in PD-1 expression on classically activated CD3 +CD8 low T cells was inversely associated with HIV-1 viremia in the first month of AHI ( r = -0.578, P = 0.015). Notably, in the first month of AHI, few CD3 +CD8 low T cells, but comparable amounts of CD3 +CD8 high T cells, responded to Gag peptides. Then, weaker HIV-1-specific T-cell responses were induced in CD3 +CD8 low T cells than CD3 +CD8 high T cells at the 3rd and 12th months of AHI and in CHI. Conclusions::Our findings suggest that CD3 +CD8 low T cells play an anti-HIV role in the first month of infection due to their abundance but induce a weak HIV-1-specific immune response. Subsequently, CD3 +CD8 low T-cell number decreased gradually as infection persisted, and their anti-HIV functions were inferior to those of CD3 +CD8 high T cells.

Objective:To evaluate the effectiveness of hepatitis B prevention and control in Tibet Autonomous Region by comparative analysis of the results of seroepidemiological surveys of hepatitis B in 2014 and 2020.Methods:The required sample size was calculated based on the estimated HBsAg positivity rates of permanent residents aged 1-4, 5-14, 15-29, and 30-69 years. A total of 7 163 people and 4 802 people were required in 2014 and 2020, respectively. The subjects were selected by stratified multistage cluster random sampling method, using questionnaires to obtain basic information, and 5 ml of venous blood was collected from each subject to detect HBsAg, anti-HBs, and anti-HBc, and rechecked the HBsAg positive samples. SPSS 22.0 software was used to analyze the survey results, calculate the positive rate and 95% confidence interval.Results:A total of 7 069 people were investigated in 2014 and 4 913 people in 2020. In 2020, the positive rate of HBsAg, anti-HBs, and anti-HBc was 9.20% (452/4 913), 37.11% (1 823/4 913), and 32.75% (1 609/4 913), respectively, and decreased by 22.95%, 15.54%, and 1.92% as compared with the rate in 2014. The positive rate of HBsAg of people aged 1-, 5-, 15- and 30-69 years in 2020 was 2.23% (8/358), 2.85% (20/701), 6.86% (69/1 006) and 12.46%(355/2 848), respectively, decreased by 61.82%, 62.75%, 54.81% and 24.21% as compared with the rate in 2014. The positive rate of anti-HBs of people aged 1-4 years was 52.79% (189/358), 10.30% increased compared with 2014; for people aged 5-, 15-, and 30-69 years was 32.67% (229/701), 37.67% (379/1 006) and 36.03%(1 026/2 848), respectively, decreased by 20.84%, 14.13% and 16.52% as compared with the rate in 2014. The positive rate of anti-HBc of people aged 1-, 5-, 15-, 30-69 years was 4.19% (15/358), 6.42%(45/701), 21.07% (212/1 006), and 46.95% (1 337/2 848), respectively, decreased by 59.63%, 58.93%, 50.49%, and 12.10% as compared with the rate in 2014.Conclusions:The prevention and control of hepatitis B in Tibet have made partial achievements. The prevalence of HBsAg among people aged 1-69 years in 2020 had declined compared with 2014, but it is still at a high epidemic level. People have a high risk of HBV infection for a low level of anti-HBs. It is necessary to strengthen the vaccination of hepatitis B further and effectively implement the strategy of blocking mothers and children of the hepatitis B virus.

Objective:To investigate the clinical manifestations, pathological features, treatment and prognosis of primary bone lymphoma in children.Methods:The clinical data of children who were initially diagnosed as primary bone lymphoma and treated in Beijing Children's Hospital Affiliated to Capital Medical University from January 2016 to January 2020 were retrospectively analyzed, including gender, onset age, primary involvement site, clinical stage, pathological type, fracture, and clinical outcome. The related literature was reviewed.Results:All 11 children were initially diagnosed as primary bone lymphoma, with a median age of onset of 8.6 years old (2.7-12.3 years old), including 7 males and 4 females. There were 7 cases of diffuse large B-cell lymphoma (DLBCL), 3 cases of B lymphoblastic lymphoma (BLL), and 1 case of anaplastic large cell lymphoma (ALCL). The initial symptoms were bone pain in 8 cases, local swelling in 1 case, limp in 1 case, and fever in 1 case. One case was in stage Ⅰ, 7 cases were in stageⅡ, and 3 cases were in stage Ⅳ, and the most common sites of involvement were femur and tibia. All 11 cases were treated with chemotherapy according to different pathological types, with a median follow-up time of 45 months (7-80 months). Ten cases got complete remission, 1 case of BLL died of bone marrow recurrence after chemotherapy remission.Conclusions:The clinical manifestations of primary bone lymphoma in children are insidious, DLBCL is the most common pathological type, and the prognosis is good after standardized treatment.