Autoimmune hepatitis (AIH) is a chronic, immune-mediated liver injury of unknown etiology. The onset of this disease involves the activation and recruitment of diverse immune and non-immune cells, which in turn trigger hepatic damage. Immune checkpoint molecules (ICM) are expressed on the surface of multiple cell types. By regulating cellular functional states, they help limit the intensity and duration of immune responses, thereby preventing excessive inflammation and tissue damage, and maintaining immune homeostasis. In AIH, however, this natural "braking" mechanism is impaired, leading to aberrant activation of both immune and non-immune cells and the breakdown of immune homeostasis. Consequently, ICM are likely to play a critical role in the pathogenesis of AIH. A deeper understanding of the function of ICM in AIH not onlyadvances our insight into the disease mechanism, but also suggests that targeting these molecules may represent a promising therapeutic strategy for the treatment of AIH.

Objective:To explore the feasibility of joint screening of the two primary immunodeficiency diseases [severe combined immunodeficiency (SCID) and X-linked agammaglobulinemia(XLA)] and spinal muscular atrophy(SMA) in newborns by multiplex real-time quantitative PCR technology, and to provide evidence for early screening, diagnosis and treatment of children.Methods:Cross-sectional study. From July 2021 to January 2023, a total of 103 240 dry blood spots samples of newborns were collected which were delivered to Neonatal Disease Screening Center of Zhejiang by cold chain transportation. The concentrations of the T cell receptor excision ring (TREC), Kappa deletion of the recombinant excision loop (KREC), and exon 7 deletion of Survival Motor Neuron 1 (SMN1) gene in dry blood spots were simultaneously detected by multiplex real-time fluorescence quantitative PCR, taken ribonuclease P/MRP 30 000 subunits (RPP30) as an internal reference gene. The positive newborns were further diagnosed by other laboratory tests and gene sequencing was taken as gold standard. Children samples from 1 case of SCID, 3 cases of XLA and 2 cases of SMA were used for positive verification. The correlation between detected concentration of TREC/KREC and basic information in newborns were analyzed. The differences among groups for each factor were analyzed.Results:One case of SCID, 2 cases of XLA, 9 cases of SMA and 7 cases of other genetic diseases (4 cases of DiGeorge syndrome, 1 case of trisomy 21 syndrome, 1 case of Noonan syndrome and 1 case of super male syndrome) were identified by multiplex real-time fluorescence quantitative PCR. The positive predictive values of screening neonatal SCID, XLA and SMA were 2.44% (1/41), 2.78% (2/72) and 9/9 respectively. Taking the samples from clinically diagnosed 1 case of SCID, 3 cases of XLA and 2 cases of SMA as positive validation samples, which were all identified. The detected results of TREC/KREC correlated with time of blood collection, sex, weight, gestational age and delivery mode of newborns, whose r values were 0.162/0.187, 0.066/0.032, 0.045/0.042, ?0.015/?0.088 and 0.014/0.068 respectively (all P<0.05). Conclusions:Relying on current neonatal screening platform in Zhejiang, it is feasible to screen jointly two kinds of primary immunodeficiency diseases and spinal muscular atrophy in newborns by multiple real-time fluorescence quantitative PCR technology.

Objective:To investigate the underlying mechanism behind the significant reduction in intracellular virus loads after respiratory syncytial virus (RSV) and influenza viruses infect respiratory epithelial cells overexpressing the chemokine (C-C motif) receptor 1 (CCR1).Methods:A549 cells were infected with respiratory syncytial virus (RSV), influenza A viruses (H1N1, H3N2), or influenza B virus (FluB), and the expression of chemokine (C-C motif) ligand 5 (CCL5) and CCR1 were detected by qRT-PCR, ELISA, and Western blot. After overexpressing or knocking down CCR1 in A549 cells, these cells were infected with RSV, H1N1, H3N2, or FluB, and the expression of CCR1, heat shock protein 90 (HSP90), cyclin-dependent kinase 1 (CDK1), and viral proteins were detected by qRT-PCR and Western blot. After stimulating CCR1-overexpressed A549 cells with CCL5, Western blot was used to detect the expression of HSP90 and CDK1, and co-immunoprecipitation was used to detect the interaction between HSP90 and CCR1. CCR1 -/- mice were infected with RSV, H1N1, or H3N2 to observe the changes in the expression of HSP90, CDK1, and viral proteins with Western blot, and the inflammation in lung tissues with HE staining. One-way analysis of variance and t test were used for statistical analysis. Results:RSV, H1N1, H3N2, and FluB infections induced high expression of CCL5 in A549 cells ( P<0.05), but the expression of CCR1 showed an overall downward trend. After activating its receptor CCR1, CCL5 inhibited the replication of RSV and influenza viruses by suppressing the activity of HSP90 ( P<0.05). The experiments conducted on CCR1 -/- mice confirmed that the enhanced activity of HSP90 facilitated the replication of RSV and influenza viruses. Conclusion:RSV and influenza viruses may reduce the binding of CCL5 to CCR1 by downregulating the expression of CCR1 in respiratory epithelial cells, thereby weakening the inhibitory effect of CCR1 on HSP90 activity, which enables them to evade host immune defense.

Objective:To investigate the underlying mechanism behind the significant reduction in intracellular virus loads after respiratory syncytial virus (RSV) and influenza viruses infect respiratory epithelial cells overexpressing the chemokine (C-C motif) receptor 1 (CCR1).Methods:A549 cells were infected with respiratory syncytial virus (RSV), influenza A viruses (H1N1, H3N2), or influenza B virus (FluB), and the expression of chemokine (C-C motif) ligand 5 (CCL5) and CCR1 were detected by qRT-PCR, ELISA, and Western blot. After overexpressing or knocking down CCR1 in A549 cells, these cells were infected with RSV, H1N1, H3N2, or FluB, and the expression of CCR1, heat shock protein 90 (HSP90), cyclin-dependent kinase 1 (CDK1), and viral proteins were detected by qRT-PCR and Western blot. After stimulating CCR1-overexpressed A549 cells with CCL5, Western blot was used to detect the expression of HSP90 and CDK1, and co-immunoprecipitation was used to detect the interaction between HSP90 and CCR1. CCR1 -/- mice were infected with RSV, H1N1, or H3N2 to observe the changes in the expression of HSP90, CDK1, and viral proteins with Western blot, and the inflammation in lung tissues with HE staining. One-way analysis of variance and t test were used for statistical analysis. Results:RSV, H1N1, H3N2, and FluB infections induced high expression of CCL5 in A549 cells ( P<0.05), but the expression of CCR1 showed an overall downward trend. After activating its receptor CCR1, CCL5 inhibited the replication of RSV and influenza viruses by suppressing the activity of HSP90 ( P<0.05). The experiments conducted on CCR1 -/- mice confirmed that the enhanced activity of HSP90 facilitated the replication of RSV and influenza viruses. Conclusion:RSV and influenza viruses may reduce the binding of CCL5 to CCR1 by downregulating the expression of CCR1 in respiratory epithelial cells, thereby weakening the inhibitory effect of CCR1 on HSP90 activity, which enables them to evade host immune defense.

Objective:To explore the feasibility of joint screening of the two primary immunodeficiency diseases [severe combined immunodeficiency (SCID) and X-linked agammaglobulinemia(XLA)] and spinal muscular atrophy(SMA) in newborns by multiplex real-time quantitative PCR technology, and to provide evidence for early screening, diagnosis and treatment of children.Methods:Cross-sectional study. From July 2021 to January 2023, a total of 103 240 dry blood spots samples of newborns were collected which were delivered to Neonatal Disease Screening Center of Zhejiang by cold chain transportation. The concentrations of the T cell receptor excision ring (TREC), Kappa deletion of the recombinant excision loop (KREC), and exon 7 deletion of Survival Motor Neuron 1 (SMN1) gene in dry blood spots were simultaneously detected by multiplex real-time fluorescence quantitative PCR, taken ribonuclease P/MRP 30 000 subunits (RPP30) as an internal reference gene. The positive newborns were further diagnosed by other laboratory tests and gene sequencing was taken as gold standard. Children samples from 1 case of SCID, 3 cases of XLA and 2 cases of SMA were used for positive verification. The correlation between detected concentration of TREC/KREC and basic information in newborns were analyzed. The differences among groups for each factor were analyzed.Results:One case of SCID, 2 cases of XLA, 9 cases of SMA and 7 cases of other genetic diseases (4 cases of DiGeorge syndrome, 1 case of trisomy 21 syndrome, 1 case of Noonan syndrome and 1 case of super male syndrome) were identified by multiplex real-time fluorescence quantitative PCR. The positive predictive values of screening neonatal SCID, XLA and SMA were 2.44% (1/41), 2.78% (2/72) and 9/9 respectively. Taking the samples from clinically diagnosed 1 case of SCID, 3 cases of XLA and 2 cases of SMA as positive validation samples, which were all identified. The detected results of TREC/KREC correlated with time of blood collection, sex, weight, gestational age and delivery mode of newborns, whose r values were 0.162/0.187, 0.066/0.032, 0.045/0.042, ?0.015/?0.088 and 0.014/0.068 respectively (all P<0.05). Conclusions:Relying on current neonatal screening platform in Zhejiang, it is feasible to screen jointly two kinds of primary immunodeficiency diseases and spinal muscular atrophy in newborns by multiple real-time fluorescence quantitative PCR technology.

Primary ciliary dyskinesia(PCD)is a rare monogenic disorder primarily associated with structural and functional abnormalities of motile cilia.It is typically inherited in an autosomal recessive pattern.The disease affects multiple organs,and the variability in clinical phenotypes,along with genetic heterogeneity significantly complicates its diagnosis.Although the application of clinical exome sequencing has significantly improved the diagnostic rate of PCD,more than 30％of patients are still unable to obtain a definitive diagno-sis.This article reviews and discusses the pathogenesis,diagnostic methods,and expanding genetic diag-nostic approaches for patients with PCD that are negative for exome sequencing.The aim of this article is to assist clinicians in selecting more advanced emerging genetic testing technologies,with the hope of increasing the positive diagnostic rate of PCD,deepening the understanding of its genetic pathogenesis,and laying a foundation for the practice of gene therapy in the future.

Objectives:To explore the antitumor effects of redox-responsive nanoparticles containing platinum(Ⅳ)—NP@Pt(Ⅳ) in ovarian cancer.Methods:Redox-responsive polymer carriers were synthesized. Polymer carriers and platinum(Ⅳ)—Pt(Ⅳ) can self-assemble into NP@Pt(Ⅳ). Inductively coupled plasma mass spectrometry was performed to detect the platinum release from NP@Pt(Ⅳ) in reducing environment and the platinum content in ovarian cancer cells ES2 treated with cisplatin, Pt(Ⅳ) and NP@Pt(Ⅳ). The proliferation ability of the ovarian cancer cells were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cellular apoptosis was assessed by flow cytometry. Collection of primary ovarian cancer tissues from patients with primary high-grade serous ovarian cancer who were surgically treated at the Cancer Hospital of the Chinese Academy of Medical Sciences from October to December 2022. The high-grade serous ovarian cancer patient-derived xenograft (PDX) mice were intravenously injected with Cy7.5 labeled NP@Pt(Ⅳ) followed by in vivo imaging system. Mice were treated with PBS, cisplatin and NP@Pt(Ⅳ). Tumor volume and weight were measured in each group. Necrosis, apoptosis and cell proliferation of tumor tissues were detected by hematoxylin-eosin (HE) staining, TUNEL fluorescence staining and Ki-67 immunohistochemistry staining. Body weight and HE staining of heart, liver, spleen, lung and kidney of mice in each group were measured.Results:The platinum release of NP@Pt(Ⅳ) after 48 hours in reducing environment was 76.29%, which was significantly higher than that of 26.82% in non-reducing environment ( P<0.001). The platinum content in ES2 cells after 4 hours and 7 hours of treatment with NP@Pt(Ⅳ) (308.59, 553.15 ng/million cells) were significantly higher than those of Pt(Ⅳ) (100.21, 180.31 ng/million cells) and cisplatin (43.36, 50.36 ng/million cells, P＜0.05). The half inhibitory concentrations of NP@Pt(Ⅳ) in ovarian cancer cells ES2, A2780, A2780DDP were 1.39, 1.42 and 4.62 μmol/L, respectively, which were lower than those of Pt(IV) (2.89, 7.27, and 16.74 μmol/L) and cisplatin (5.21, 11.85, and 71.98 μmol/L). The apoptosis rate of ES2 cells treated with NP@Pt(Ⅳ) was (33.91±3.80)%, which was significantly higher than that of Pt(Ⅳ) [(16.28±2.41)%] and cisplatin [(15.01±1.17)%, P＜0.05]. In high-grade serous ovarian cancer PDX model, targeted accumulation of Cy7.5 labeled NP@Pt(Ⅳ) at tumor tissue could be observed. After the treatment, the tumor volume of mice in NP@Pt(IV) group was (130±98) mm 3, which was significantly lower than those in control group [(1 349±161) mm 3, P<0.001] and cisplatin group [(715±293) mm 3, P=0.026]. The tumor weight of mice in NP@Pt(IV) group was (0.17±0.09)g, which was significantly lower than those in control group [(1.55±0.11)g, P<0.001] and cisplatin group [(0.82±0.38)g, P=0.029]. The areas of tumor necrosis and apoptosis in mice treated with NP@Pt(Ⅳ) were higher than those in mice treated with cisplatin. Immunohistochemical staining revealed that there were low expressions of Ki-67 at tumor tissues of mice treated with NP@Pt(Ⅳ) compared with cisplatin. The change in body weight of mice in NP@Pt(Ⅳ) group was not significantly different from that of the control group [(18.56±2.04)g vs.(20.87±0.79)g, P=0.063]. Moreover, the major organs of the heart, liver, spleen, lung, and kidney were also normal by HE staining. Conclusion:Redox-responsive NP@Pt(Ⅳ), produced in this study can enhance the accumulation of cisplatin in ovarian cancer cells and improve the efficacy of ovarian cancer chemotherapy.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ 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) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had 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 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ 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) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had 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 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

OBJECTIVE: To describe negative conversion and rebound of patients with severe and critical acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection after treatment with Nirmatrelvir/Ritonavir, and to analyze related factors associating with failure of SARS-CoV-2 negative conversion and relapse and prognosis. METHODS: A single center retrospective cohort study was conducted. Patients aged ≥ 16 years old who were diagnosed with severe or critical SARS-CoV-2 infection and took Nirmatrelvir/Ritonavir for 5 days in Peking University First Hospital from December 7, 2022 to January 27, 2023, were included. General characteristics and clinical data were collected from electronic medical record system. The Kaplan-Meier curve of SARS-CoV-2 negative conversion was drawn. Factors with P < 0.10 were incorporated into multivariate Logistic regression model to analyze the relationship between the factors and persistent nucleic acid positive and rebound. RESULTS: A total of 31 severe and 37 critical SARS-CoV-2 infection patients were included. The median duration from initiation of Nirmatrelvir/Ritonavir to negative conversion of SARS-CoV-2 for both was 6.0 days, and the negative conversion rate on day 15 was 93.5% and 86.5%, respectively. SARS-CoV-2 rebound was observed in 7 patients (11.3%), among whom were 1 severe patient and 6 critical patients. The above 7 patients with SARS-CoV-2 rebound and 6 patients with failure of SARS-CoV-2 negative conversion were compared with 55 patients with persistent negative conversion. Factors with P < 0.10, including the lowest lymphocyte count (LYM), the highest D-dimer, the highest procalcitonin (PCT), the lowest Ct value, cardiovascular diseases other than hypertension and coronary heart disease, were incorporated into multivariate Logistic regression analysis. The decreased LYM [odds ratio (OR) = 0.146, 95% confidence interval (95%CI) was 0.031-0.689, P = 0.015] and the increased PCT (OR = 2.008, 95%CI was 1.042-3.868, P = 0.037) were revealed to be independent risk factors of the failure of SARS-CoV-2 negative conversion or rebound. The proportion of mechanical ventilation and invasive ventilation were significantly higher in patients with persistent SARS-CoV-2 infection or rebound than those in patients with SARS-CoV-2 negative conversion (84.6% vs. 38.2%, 69.2% vs. 25.5%, both P < 0.01), but no significant difference in mechanical ventilation and invasive ventilation duration was observed. Compared with the patients with SARS-CoV-2 negative conversion, more patients with persistent SARS-CoV-2 infection or rebound were admitted to intensive care unit (ICU, 76.9% vs. 50.9%), and length of ICU stay in patients with persistent SARS-CoV-2 infection or rebound tended to be longer [days: 13.0 (10.3, 24.3) vs. 11.0 (5.3, 23.0), P > 0.05]. CONCLUSIONS The decreased LYM and increased PCT are independent risk factors for the failure of SARS-CoV-2 negative conversion or rebound in patients with severe and critical SARS-CoV-2 infection. Attention should be paid to these patients for their poor prognosis.
Humans ; Adolescent ; COVID-19 ; SARS-CoV-2 ; Retrospective Studies ; Ritonavir/therapeutic use* ; Critical Illness ; COVID-19 Drug Treatment