Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective:To analyze the clinical characteristics of idiopathic systemic capillary leak syndrome (ISCLS).Methods:This retrospective case series analysis included 10 patients with confirmed ISCLS who were hospitalized at Peking Union Medical College Hospital from January 1983 to August 2023. Data collected encompassed general information, symptoms, laboratory results, treatment, and prognosis.Results:Among 10 ISCLS patients, 8 were males and 2 were females. The age of onset ranged from 29 to 63 years, and it was ≥40 years in 6 cases. Nine patients had nonspecific prodromal symptoms. All 10 experienced hypotension, hemoconcentration, hypoalbuminemia, and acute kidney injury during the leakage phase, with hemodynamic recovery in the subsequent phase. Neurological abnormalities were observed in 6 patients. Three patients had coagulation disorders, and 4 showed elevated levels of IL-6, IL-8, and TNF-α. M protein was found in all patients, with 8 showing IgGκ and 2 IgGλ. Acute-phase treatment primarily involved fluid resuscitation and vasopressors. In the stable phase, 4 patients had fewer episodes with anti-plasma cell therapy; 2 continued to have episodes despite intravenous immunoglobulin (IVIG); 2 had poor outcomes with theophylline; 1 improved without treatment; and 1 was lost to follow-up.Conclusions:ISCLS is a rare disease with adult-onset, presenting nonspecific prodromal symptoms and marked hypotension during episodes. All patients had monoclonal gammopathy. Effective treatment for the stable phase is lacking, though anti-plasma cell therapy may offer some benefit.

Objective:To investigate the correlation between the degree of hepatic fibrosis and early neurological deterioration (END) after intravenous thrombolysis in patients with acute ischemic stroke (AIS) and its predictive value.Methods:Patients with AIS received intravenous thrombolysis at Nanjing Jiangbei Hospital from January 2018 to March 2023 were retrospectively included. Hepatic fibrosis-4 index (FIB-4) was used to evaluate the degree of hepatic fibrosis in patients. FIB-4 ≥ 2.67 was defined as severe hepatic fibrosis. END was defined as an increase of ≥4 from baseline on the National Institutes of Health Stroke Scale (NIHSS) score within 24 h after intravenous thrombolysis. The relevant factors of END were analyzed through univariate analysis and multivariate logistic regression model. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of FIB-4 for END. Results:A total of 313 patients were included, of which 184 (58.8%) were male, aged 64.8±11.8 years old. The median baseline NIHSS score was 6 (interquartile range, 4-9), and the median FIB-4 was 1.76 (interquartile range, 1.28-2.56). Forty-five patients (14.4%) experienced END. Multivariate logistic regression analysis showed that after adjusting for other confounding factors, higher FIB-4 was significantly independently correlated with END (odds ratio 2.121, 95% confidence interval 1.422-3.162; P=0.001). ROC curve analysis shows that FIB-4 has a good predictive value for END (the area under the curve 0.689, 95% confidence interval 0.595-0.784; P=0.001). The optimal cutoff value of FIB-4 was 1.82, and its sensitivity and specificity in predicting END were 71.1% and 54.9%, respectively. Conclusion:FIB-4 has good predictive value for END in patients with AIS after intravenous thrombolysis.

We wished to summarize the clinical features of common variable immunodeficiency (CVID) complicated by non-cirrhotic portal hypertension (NCPH) and to deepen our understanding of it. The case data of CVID complicated with NCPH admitted to Peking Union Medical College Hospital from January 1983 to May 2021 were analyzed retrospectively to summarize their clinical characteristics. Six patients with CVID combined with NCPH (three of each sex; 16-45 years) were assessed. Four patients had portal hypertension. All patients had anemia, splenomegaly, a normal serum level of albumin and transaminases, and possibly increased levels of alkaline phosphatase and gamma-glutamyl transpeptidase. Two patients were diagnosed with esophagogastric fundic varices by gastroscopy. Two patients underwent splenectomy (which improved hematologic abnormalities partially). Four patients had autoimmune disease. Two cases were diagnosed with nodular regenerative hyperplasia (NRH) upon liver biopsy. Six patients were administered intravenous immunoglobulin-G (0.4-0.6 g/kg bodyweight) once every 3-4 weeks as basic therapy. Often, CVID complicated with NCPH has: (1) The manifestations of portal hypertension as the primary symptom. (2) Autoimmune-related manifestations. Imaging can provide important diagnostic clues. The etiology may be related to hepatic NRH and splenomegaly due to recurrent infections.

Objective:To investigate the role of dendritic cells (DC) in Chlamydia muridarum ( Cm) respiratory infection and their effect on adaptive immune response. Methods:C57BL/6 mice were exposed to 1×10 3 inclusion-forming units (IFU) of Cm through inhalation to establish the mouse model of Cm respiratory infection. The proportion of CD11c + MHCⅡ + DC and the expression of costimulatory molecules (CD40, CD80 and CD86) in spleen tissues were detected by flow cytometry on 0, 3 and 7 d after infection. The expression of IL-12p40, IL-10 and IL-6 at mRNA level in spleen tissues was detected by qPCR. Mouse splenic DC isolated on 7 d after Cm infection were sorted by magnetic beads and then transferred to recipient mice. Th1 response in the recipient mice was measured using intracellular cytokine staining 14 d after infection. Results:Cm respiratory infection induced massive infiltration of DC and promoted the expression of costimulatory molecules on splenic DC. The expression of IL-12 and IL-10 at mRNA level in splenic DC reached the peak on 3 d after infection. Transferring the splenic DC of Cm-infected mice into the recipient mice could alleviate the disease condition in the recipient mice after Cm infection with reduced Cm inclusion-forming units in lung tissues and significantly increased proportion of Th1 cells in lung and spleen tissues. Conclusions:Cm respiratory infection could induce the maturation and activation of DC, which promoted Th1 immune response. DC played an important role in Cm infection.

【Objective】 To investigate the quality changes of suspended red blood cells (SRBCs) prepared from the blood of Tibetan high Hb population, and explore the availability and safety of blood collected from Tibetan high Hb population. 【Methods】 The voluntary blood donors were grouped according to the Hb concentration at the initial screening: female blood donors from Tibet Autonomous Region (>3 500 m) with Hb≥190 g/L and male blood donors with Hb≥210 g/L were classified as plateau high hemoglobin group. A total of 13 male blood donors from Tibet Autonomous Region were recruited. And the female blood donors (n=13) with Hb(115~165) g/L and male blood donors (n=12) with Hb(120~185) g/L from Chengdu were classified as control group. Whole blood of 200 mL specification was centrifuged to remove the plasma, and MAP additive solution was added to prepare SRBCs, then SRBCs were divided into four aliquots (50 mL/bag and stored at 4℃. Parameters as blood routine, free Hb and hemolysis rate were measured aseptically at day 1, 14, 21, 35 of storage. And 10 mL SRBCs was used to extract membrane proteins for tyrosine phosphorylation detection of band 3 protein. 【Results】 The RBCs counts(×10¹²/L), hematocrit(%) and hemoglobin(g/L) of Tibetan high Hb group and control group were 6.76±0.95 vs 4.65±0.52, 63.3±6.8 vs 43.1±4.4 and 214.4±19.8 vs 143.2±16.9 (P<0.01). The erythrocyte deformability test on the day 1, 14, 21, 35 of storage showed that the deformability of SRBCs prepared from Tibetan high Hb group was significantly lower than that of the control group under shear stress of 3, 5.33, 9.49, 16.87, and 30 Pa, while the hemolysis rate of SRBCs prepared from the Tibetan high Hb group and the control group on the day 1, 14, 21, 35 were 0.050 2±0.040 2 vs 0.022 2±0.011 1, 0.055 4±0.043 vs 0.032 1±0.028 7, 0.061 2±0.025 9 vs 0.034 3±0.031 7 and 0.069 6±0.032 0 vs 0.044 0±0.033 3 (P<0.05). Western blotting showed that the cytoplasmic N-terminal Y21 of band 3 protein of SRBCs prepared from Tibetan high Hb group was highly phosphorylated. 【Conclusion】 The deformability of SRBCs prepared from the Tibetan high Hb group was significantly lower while the hemolysis rate of SRBCs was higher than that of the control group. The hemolysis rate of the SRBCs at the end of storage prepared from the Tibetan high Hb group meets the requirements of the national standard GB18469-2012(<0.8%). The increase of hemolysis rate of SRBCs prepared from the Tibetan high Hb group was closely related to the phosphorylation of band 3 protein.

We presented an adolescent with recurrent intracranial hemorrhage and skin lesion. The diagnosis was unclear and the treatment was difficult. Through a multidisciplinary effort type Ⅰ interferon disease was suspected and later, an interferon-stimulated gene was further detected. Considering the high morbidity and fatality rate of recurrent intracranial hemorrhage, tofacitinib and hydroxychloroquine were administered. After treatment, the livedo reticularis was significantly regressed. Unfortunately, the intracranial hemorrhage recurred due to a pre-existing cerebral aneurysm, leading to death of the patient. The diagnosis and treatment of this case highlight the importance of multidisciplinary collaboration in the diagnosis and treatment of difficult and rare diseases.

Objective:To explore the impact of Coronavirus disease 2019 (COVID-19) epidemic on career choosing perspective among medical students and to analyze the related factors.Methods:Semi-structured telephone interviews were conducted during March 1-25 2020 among 19 medical students of 8-year program from Peking Union Medical College. The grounded theory and thematic analysis were applied to code the data and identify categories and factors.Results:Among the 19 respondents aged 19-26 years, 9 were males and 10 were female; 10 were at the clinical stage, and 9 were at the premedical stage; 3 respondents had family members involved in medical profession. Thematic analysis identified 6 main categories that affect the variability of medical students' career prospects under the COVID-19 pandemic. The 6 themes were individual characteristics of students; occupational characteristics; systemic factors; COVID-19 events; stressors of physicians and influence of job satisfaction.The outbreak affected everyone's mind of future career to varying degrees. The participants had been exposed to more negative aspects, while only one participant changed her career intention. There were conflicting views on whether to choose some specialties in future, such as respiratory medicine, infectious disease and critical care medicine. The participants feel more pressure as a doctor from the attitude of the public. Almost all participants mentioned feeling unsafe due to the high risk of occupational exposure and doctor-patient relationships. Most valued the support from their family, faculty, classmates, and volunteers. Many participants expressed their hope to improve the medical policies and systems.Conclusions:The influence of COVID-19 outbreak on medical students' career choosing can be positive as well as negative in different degrees. However, we found no evidence that it altered their perspectives substantially.

Objective:To analyze the clinical manifestation, laboratory examination, treatment and prognosis of common variable immunodeficiency (CVID) in single center of Chinese population.Methods:The clinical data of 75 cases of CVID, diagnosed according to European Society for Immunodeficiency (ESID) criteria and admitted in Peking Union Medical College Hospital from January 1983 to May 2021 were retrospectively analyzed.Results:The main clinical manifestations of CVID were respiratory abnormality (68.0%,51/75), blood system abnormality (66.7%,50/75), liver and spleen involvement (66.7%,50/75), gastrointestinal abnormality (46.7%,35/75), autoimmune abnormality (29.3%,22/75). Immunoglobulin decreased significantly (median IgG 2.4 g/L, median IgA 0.1 g/L, median IgM 0.1 g/L). Lymphocyte subsets indicated that CD4 +T cells decreased (median 471/μl), CD8 +T cells increased (median 620/μl), CD4 +/CD8 +T calls proportion inverted (median 0.7), and NK cells and B cells decreased (median 44/μl, 115/μl, respectively). During hospitalization, their conditions were improved after IgG replacement therapy, supplemented with anti-infection and nutritional support therapy. Forty seven discharged patients were followed up, and only 16 patients insisted on regular IgG replacement therapy after discharge. Conclusions:The clinical manifestations of CVID are varied, and multiple systems may be involved, including autoimmune abnormalities. The treatment based on IgG replacement has a certain curative effect.

【Objective】 To investigate the removal efficacy of inflammatory cytokines and blood compatibility of modified PBTNF. 【Methods】 Acrylic acid (AA) was firstly UV-grafted onto the surface of PBTNF to negatively charge the surface of the material. Subsequently, the three positively charged polyelectrolytes, DA, PEI, and CS were respectively electrostatic self-assembled with GO on the surface of PBTNF, forming two layers of film with GO as the outer layer: PBTNF-(DA/GO)2, PBTNF-(PEI/GO)2, PBTNF-(CS/GO)2. 【Results】 Scanning electron microscopy results showed that compared with the PBTNF grafted with AA, the adhesion of particles was observed on the surface of the three modified materials, and the photo shows that the color of the material surface was deepened after electrostatic self-assembly. The results of wettability showed that the surface hydrophilicity was significantly improved, indicating that the electrostatic self-assembled membrane was successfully immobilized on the surface of PBTNF. The removal efficiency (%) of IL-1β for PBTNF-(DA/GO)2, PBTNF-(PEI/GO)2 and PBTNF-(CS/GO)2 were 69.00±7.36 vs -2.35±2.69 vs -1.59±3.26 (P<0.05). The removal efficiency of IL-6 (%) were 40.15±1.86 vs -13.46±5.72 vs -1.21±3.41 (P<0.05). The removal efficiency of IL-8 (%) were 96.90±0.97 vs 17.84±11.74 vs 43.68±17.38 (P<0.05). The removal efficiency of TNF-α (%) was 44.46±2.50 vs 14.90±7.12 vs 20.64±1.22 (P<0.05). Plasma protein adsorption results (total protein, immunoglobulin G, albumin) and red blood cell deformability index showed that there was no statistical difference among the three modified PBTNFs and the control group (P>0.05). Although the red blood cell osmotic fragility (g/L) of the three modified PBTNFs is higher than that of the former: control group vs PBTNF-(DA/GO)2 vs PBTNF-(PEI/GO)2 vs PBTNF-(CS/GO)2: 4.39±0.05 vs 4.62±0.02 vs 4.48±0.03 vs 4.90±0.03 (P<0.05), the hemolysis rate (%) of them were all less than 5%, and PBTNF-(DA/GO)2 performed the lowest hemolysis rate which was (0.03±0.01)% (compared with PBTNF-(PEI/GO)2, P<0.05). The coagulation function test results showed that compared with the control group, the fibrinogen (g/L) of the three modified PBTNFs had no statistical difference (P>0.05); the activated partial thrombo plastin time (S) slightly extended, but all within the normal range of clinical standard; and the prothrombin time (S) of PBTNF-(CS/GO)2 was prolonged(P<0.05). 【Conclusion】 Among the three positively charged polyelectrolytes, including DA, PEI, and CS, PBTNF-(DA/GO)2 performed the best removal rate of inflammatory cytokines, and the blood compatibility evaluation results showed that PBTNF-(DA/GO)2 had no significant effect on red blood cells and coagulation function. Consequently, in the study of inflammatory cytokines adsorption, DA is expected to be the optimal polyelectrolyte assembling with GO for further research.