ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

OBJECTIVES: To study the significance of serum 25-hydroxyvitamin D₃ [25-(OH)D₃] level in the clinicopathological characteristics and prognosis of children with immunoglobulin A vasculitis nephritis (IgAVN). METHODS: A retrospective analysis was conducted on the clinical data of children with IgAVN who underwent renal biopsy at Suzhou Hospital Affiliated to Anhui Medical University and Jinling Hospital of the Medical School of Nanjing University from June 2015 to June 2020. Based on serum 25-(OH)D₃ level, the patients were divided into a normal group and a lower group. The clinicopathological characteristics and follow-up data of the two groups were collected and compared. RESULTS: A total of 359 children with IgAVN were included. Compared to the normal group (62 cases), the lower group (297 cases) exhibited higher incidences of hematochezia and gross hematuria, higher levels of serum creatinine, blood urea nitrogen, urinary retinol protein, urinary N-acetyl-β-D-glucosaminidase, and quantitative urinary protein, and a longer duration from renal biopsy to urinary protein becoming negative, as well as lower estimated glomerular filtration rate and albumin level (P<0.05). Renal pathology in the lower group showed a higher occurrence of tubular interstitial injury, crescent formation, segmental sclerosis in glomeruli, and inflammatory cell infiltration in the renal interstitium compared to the normal group (P<0.05). Survival analysis indicated that the cumulative renal survival rate was lower in the lower group (P<0.05). Multivariate Cox regression analysis revealed that low serum 25-(OH)D₃ level is an independent risk factor for poor prognosis in children with IgAVN. CONCLUSIONS Children with IgAVN and low serum 25-(OH)D₃ level have relatively severe clinicopathological manifestations. Low serum 25-(OH)D₃ level is an independent risk factor for poor prognosis in children with IgAVN.
Humans ; Male ; Female ; Child ; Prognosis ; Retrospective Studies ; Calcifediol/blood* ; Child, Preschool ; Adolescent ; Glomerulonephritis, IGA/mortality* ; Vasculitis/pathology* ; IgA Vasculitis/mortality*

mRNA gene therapy has attracted much attention due to its advantages such as scalability, modification, no need to enter the nucleus and no integration of host genes. In gene therapy, safe and effective delivery of mRNA into cells is critical for the success of gene therapy. In this study, we designed and synthesized an amphiphilic cationic lipopeptide gene vector (dendritic arginine & disulfide bond-containing cationic lipopeptide, RLS) enriched with branched arginine. We achieved a 1.5-fold higher mRNA transfection efficiency in zebrafish compared to the commercial reagent Lipofectamine 2000, and confirmed its good biosafety by in vitro cytotoxicity and in vivo biosafety. First, we characterized the chemical composition of the cationic lipid peptides by nuclear magnetic resonance hydrogen spectroscopy (¹H NMR) and time-of-flight mass spectrometry (MS). The results of particle size and potential tested by dynamic light scattering particle size analysis showed that at a nitrogen/phosphorus (N/P) ratio of 20, the RLS/mRNA composite assemblies formed homogeneous nanoparticles with an average particle size of about 220 nm and a surface ζ potential of about +21 mV. In vitro gene transfection, the transfection experiments demonstrated that RLS exhibited 1.2-fold higher transfection efficiency in human embryonic kidney 293 cells (HEK293) and 3-fold higher transfection efficiency in rat mesenchymal stem cells (MSC) compared to Lipofectamine 2000. In addition, after microinjection of RLS into zebrafish embryos, we evaluated the survival, hatching, and teratogenicity rates, all of which confirmed its favorable in vivo safety profile. Thus, this amphiphilic cationic lipid peptide RLS, enriched with branched arginine, exhibits excellent mRNA delivery properties and safety. These findings highlight its potential as a promising gene therapy tool.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

AIM To investigate the effects of total Astragalus saponins on the improvement of sarcopenia in a rat model of type 2 diabetes mellitus(T2DM).METHODS The rats were divided into the normal group for a normal feeding and the model group for the feeding of high-sugar and high-fat diet combined with intraperitoneal injection of STZ to establish a T2DM model.The successful model rats were randomly divided into the model group,the metformin group(0.2 g/kg)and the total Astragalus saponins group(80 mg/kg),and given corresponding doses of drugs by gavage.After 12 weeks administration,the rats had their FBG,postprandial blood glucose(PG2h)and wet weight of skeletal muscle measured;their serum levels of INS,C-peptide(C-P),IGF-1,TNF-α and IL-1β detected by ELISA;their morphological changes of skeletal muscle observed by HE staining;their protein expressions of PI3K,p-Akt,mTOR,S6K1,FoxO1 and Murf1 in skeletal muscle detected by Western blot;and their mRNA expressions of Pi3k,Akt and mtor in skeletal muscle detected by RT-qPCR method.RESULTS Compared with the model group,the total Astragalus saponins group displayed decreased levels of FBG,PG2h,OGTT-AUC,HOMA-IR,TNF-α and IL-1β(P＜0.01);increased levels of INS,C-P,IGF-1 and wet weight of skeletal muscle(P＜0.05,P＜0.01);improved skeletal muscle atrophy and increased protein expressions of PI3K,p-Akt,mTOR and S6K1 in skeletal muscle(P＜0.05,P＜0.01);decreased protein expressions of FoxO1 and Murf1(P＜0.05,P＜0.01);and increased mRNA expressions of Pi3k,Akt and mtor(P＜0.01).CONCLUSION The improvement effects of total Astragalus saponins on sarcopenia in T2DM rats may be associated with the regulation of PI3K/Akt/mTOR and PI3K/Akt/FoxO1 pathways.

Objective: To explore the efficacy of adjuvant programmed cell death 1 (PD-1) monoclonal antibody immunotherapy in Chinese patients with resected stage Ⅱ-Ⅲ melanoma. Methods: A total of 296 patients who underwent radical surgery for stage Ⅱ-Ⅲ cutaneous orlimb melanoma at Fudan University Shanghai Cancer Center and Shanghai Electric Power Hospital between 2017 and 2021 and received adjuvant PD-1 monoclonal antibody immunotherapy, low-dose interferon (IFN), or observational follow-up were enrolled in this study. Patients were divided into the PD-1 monoclonal antibody group (164 cases) and the IFN or observation group (IFN/OBS group, 132 cases) based on postoperative adjuvant treatment methods. Patients' disease recurrence and survival were observed. Results: Among the 296 patients, 77 had cutaneous melanoma and 219 had limb melanoma; 110 were stage Ⅱ and 186 were stage Ⅲ. Among stage Ⅱ patients, the median recurrence-free survival (RFS) in the PD-1 monoclonal antibody group (46 cases) did not reach, while the median RFS in the IFN/OBS group (64 cases) was 36 months. The 1-year RFS rates were 85.3% and 92.1% and the 2-year RFS rates were 71.9% and 63.7% in the PD-1 monoclonal antibody group and the IFN/OBS group, respectively, with no statistically significant difference (P=0.394). Among stage Ⅲ patients, the median RFS rates in the PD-1 monoclonal antibody group (118 cases) and the IFN/OBS group (68 cases) were 23 and 13 months, respectively. The 1-year RFS rates were 70.0% and 51.8% and the 2-year RFS rates were 51.8% and 35.1%in the PD-1 monoclonal antibody group and the IFN/OBS group, respectively, with a statistically significant difference (P=0.010). Stratified analysis showed that the advantage of PD-1 monoclonal antibody adjuvant therapy in improving RFS persisted in the subgroups of primary ulceration (HR=0.558, 95% CI: 0.348-0.893), lymph node macroscopic metastasis (HR=0.486, 95% CI: 0.285-0.828), stage ⅢC (HR=0.389, 95% CI: 0.24-0.63), and the subgroup without BRAF/c-Kit/NRAS gene mutations (HR=0.347, 95% CI: 0.171-0.706). In terms of recurrence patterns, in stage Ⅱ patients, the recurrence and metastasis rate was 15.2% (7/46) in the PD-1 monoclonal antibody group, significantly lower than the IFN/OBS group [43.8% (28/64), P=0.002]. In stage Ⅲ melanoma patients, the recurrence and metastasis rate was 42.4% (50/118) in the PD-1 monoclonal antibody group, also lower than the IFN/OBS group [63.2% (43/68), P=0.006]. Conclusions: In real-world settings, compared with patients receiving low-dose IFN adjuvant therapy or observational follow-up, PD-1 monoclonal antibody immunotherapy can reduce the recurrence and metastasis rate of cutaneous and limb melanoma, and prolong the postoperative RFS of stage Ⅲ cutaneous and limb melanoma patients. Patients with a heavier tumor burden benefit more from immunotherapy.
Humans ; Antibodies, Monoclonal/therapeutic use* ; Apoptosis ; China ; Disease-Free Survival ; East Asian People ; Immunotherapy ; Interferon-alpha/therapeutic use* ; Lymphatic Metastasis ; Melanoma/pathology* ; Programmed Cell Death 1 Receptor/therapeutic use* ; Skin Neoplasms/pathology* ; Melanoma, Cutaneous Malignant

Objective: To explore the efficacy of adjuvant programmed cell death 1 (PD-1) monoclonal antibody immunotherapy in Chinese patients with resected stage Ⅱ-Ⅲ melanoma. Methods: A total of 296 patients who underwent radical surgery for stage Ⅱ-Ⅲ cutaneous orlimb melanoma at Fudan University Shanghai Cancer Center and Shanghai Electric Power Hospital between 2017 and 2021 and received adjuvant PD-1 monoclonal antibody immunotherapy, low-dose interferon (IFN), or observational follow-up were enrolled in this study. Patients were divided into the PD-1 monoclonal antibody group (164 cases) and the IFN or observation group (IFN/OBS group, 132 cases) based on postoperative adjuvant treatment methods. Patients' disease recurrence and survival were observed. Results: Among the 296 patients, 77 had cutaneous melanoma and 219 had limb melanoma; 110 were stage Ⅱ and 186 were stage Ⅲ. Among stage Ⅱ patients, the median recurrence-free survival (RFS) in the PD-1 monoclonal antibody group (46 cases) did not reach, while the median RFS in the IFN/OBS group (64 cases) was 36 months. The 1-year RFS rates were 85.3% and 92.1% and the 2-year RFS rates were 71.9% and 63.7% in the PD-1 monoclonal antibody group and the IFN/OBS group, respectively, with no statistically significant difference (P=0.394). Among stage Ⅲ patients, the median RFS rates in the PD-1 monoclonal antibody group (118 cases) and the IFN/OBS group (68 cases) were 23 and 13 months, respectively. The 1-year RFS rates were 70.0% and 51.8% and the 2-year RFS rates were 51.8% and 35.1%in the PD-1 monoclonal antibody group and the IFN/OBS group, respectively, with a statistically significant difference (P=0.010). Stratified analysis showed that the advantage of PD-1 monoclonal antibody adjuvant therapy in improving RFS persisted in the subgroups of primary ulceration (HR=0.558, 95% CI: 0.348-0.893), lymph node macroscopic metastasis (HR=0.486, 95% CI: 0.285-0.828), stage ⅢC (HR=0.389, 95% CI: 0.24-0.63), and the subgroup without BRAF/c-Kit/NRAS gene mutations (HR=0.347, 95% CI: 0.171-0.706). In terms of recurrence patterns, in stage Ⅱ patients, the recurrence and metastasis rate was 15.2% (7/46) in the PD-1 monoclonal antibody group, significantly lower than the IFN/OBS group [43.8% (28/64), P=0.002]. In stage Ⅲ melanoma patients, the recurrence and metastasis rate was 42.4% (50/118) in the PD-1 monoclonal antibody group, also lower than the IFN/OBS group [63.2% (43/68), P=0.006]. Conclusions: In real-world settings, compared with patients receiving low-dose IFN adjuvant therapy or observational follow-up, PD-1 monoclonal antibody immunotherapy can reduce the recurrence and metastasis rate of cutaneous and limb melanoma, and prolong the postoperative RFS of stage Ⅲ cutaneous and limb melanoma patients. Patients with a heavier tumor burden benefit more from immunotherapy.
Humans ; Antibodies, Monoclonal/therapeutic use* ; Apoptosis ; China ; Disease-Free Survival ; East Asian People ; Immunotherapy ; Interferon-alpha/therapeutic use* ; Lymphatic Metastasis ; Melanoma/pathology* ; Programmed Cell Death 1 Receptor/therapeutic use* ; Skin Neoplasms/pathology* ; Melanoma, Cutaneous Malignant

Adult ; Age Factors ; China ; Famine ; Female ; Fibrosis ; Humans ; Liver Diseases ; Prenatal Exposure Delayed Effects ; Sex Factors

ObjectiveSepsis associated acute kidney injury （SA-AKI） is a critical clinical disease. The purpose of this study was to investigate the role and molecular mechanism of miR-4321 in the HK2 cellular damage induced by lipopolysaccharides （LPS）. MethodsRT-qPCR was conducted to detect the expression of miR-3165， miR-4270 and miR-4321 in LPS-induced HK2 cell model and cecal ligation and puncture （CLP）-induced renal injury model. In LPS-induced HK2 cell model， miR-4321-inhibitor was used to inhibit the miR-4321 expression. The effects of miR-4321 on cell proliferation， cell viability， cytokines and apoptosis-related protein levels were evaluated by CCK-8 analysis， EdU staining analysis and western blotting analysis， respectively. In CLP-induced renal injury model， miR-4321-Antago was used to intervene the miR-4321 expression. The changes of renal tissue structure were examined by H&E staining. The levels of serum creatinine and blood urea nitrogen （BUN） were measured by colorimetric method. ELISA was employed to assess the expression of interleukin-6 （IL-6）， interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α） in serum. IHC staining and western blotting were performed to determine the mTOR level and apoptosis-related protein expression in kidney tissues. Target genes of miR-4321 were predicted by Targetscan software and verified by dual-luciferase reporter assay. ResultsCompared with the control group， the miR-4321 expression was increased in LPS-induced HK2 cell model （n=3， t=7.154， P=0.001 3）. miR-4321 inhibitor promoted the proliferation and viability of HK2 cells， decreased the expression of LPS-induced IL-6， IL-1β and TNF-α and apoptosis-related proteins. In vivo experiments showed that miR-4321-Antago inhibited serum creatinine and BUN levels in CLP mice， improved renal injury， reduced levels of IL-1β， IL-6 and TNF-α， promoted the mTOR expression in renal tissues and inhibited the apoptosis-related protein expression. mTOR signaling pathway was believed the target gene of miR-4321. ConclusionInhibition of miR-4321 significantly alleviates SA-AKI， which may be achieved by increasing the expression of mTOR.

Objective: To analyze the clinical epidemiological characteristics including composition of pathogens , clinical characteristics, and disease prognosis acute bacterial meningitis (ABM) in Chinese children. Methods: A retrospective analysis was performed on the clinical and laboratory data of 1 610 children <15 years of age with ABM in 33 tertiary hospitals in China from January 2019 to December 2020. Patients were divided into different groups according to age,<28 days group, 28 days to <3 months group, 3 months to <1 year group, 1-<5 years of age group, 5-<15 years of age group; etiology confirmed group and clinically diagnosed group according to etiology diagnosis. Non-numeric variables were analyzed with the Chi-square test or Fisher's exact test, while non-normal distrituction numeric variables were compared with nonparametric test. Results: Among 1 610 children with ABM, 955 were male and 650 were female (5 cases were not provided with gender information), and the age of onset was 1.5 (0.5, 5.5) months. There were 588 cases age from <28 days, 462 cases age from 28 days to <3 months, 302 cases age from 3 months to <1 year of age group, 156 cases in the 1-<5 years of age and 101 cases in the 5-<15 years of age. The detection rates were 38.8% (95/245) and 31.5% (70/222) of Escherichia coli and 27.8% (68/245) and 35.1% (78/222) of Streptococcus agalactiae in infants younger than 28 days of age and 28 days to 3 months of age; the detection rates of Streptococcus pneumonia, Escherichia coli, and Streptococcus agalactiae were 34.3% (61/178), 14.0% (25/178) and 13.5% (24/178) in the 3 months of age to <1 year of age group; the dominant pathogens were Streptococcus pneumoniae and the detection rate were 67.9% (74/109) and 44.4% (16/36) in the 1-<5 years of age and 5-<15 years of age . There were 9.7% (19/195) strains of Escherichia coli producing ultra-broad-spectrum β-lactamases. The positive rates of cerebrospinal fluid (CSF) culture and blood culture were 32.2% (515/1 598) and 25.0% (400/1 598), while 38.2% (126/330)and 25.3% (21/83) in CSF metagenomics next generation sequencing and Streptococcus pneumoniae antigen detection. There were 4.3% (32/790) cases of which CSF white blood cell counts were normal in etiology confirmed group. Among 1 610 children with ABM, main intracranial imaging complications were subdural effusion and (or) empyema in 349 cases (21.7%), hydrocephalus in 233 cases (14.5%), brain abscess in 178 cases (11.1%), and other cerebrovascular diseases, including encephalomalacia, cerebral infarction, and encephalatrophy, in 174 cases (10.8%). Among the 166 cases (10.3%) with unfavorable outcome, 32 cases (2.0%) died among whom 24 cases died before 1 year of age, and 37 cases (2.3%) had recurrence among whom 25 cases had recurrence within 3 weeks. The incidences of subdural effusion and (or) empyema, brain abscess and ependymitis in the etiology confirmed group were significantly higher than those in the clinically diagnosed group (26.2% (207/790) vs. 17.3% (142/820), 13.0% (103/790) vs. 9.1% (75/820), 4.6% (36/790) vs. 2.7% (22/820), χ²=18.71, 6.20, 4.07, all P<0.05), but there was no significant difference in the unfavorable outcomes, mortility, and recurrence between these 2 groups (all P>0.05). Conclusions: The onset age of ABM in children is usually within 1 year of age, especially <3 months. The common pathogens in infants <3 months of age are Escherichia coli and Streptococcus agalactiae, and the dominant pathogen in infant ≥3 months is Streptococcus pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. ABM should not be excluded even if CSF white blood cell counts is within normal range. Standardized bacteriological examination should be paid more attention to increase the pathogenic detection rate. Non-culture CSF detection methods may facilitate the pathogenic diagnosis.
Adolescent ; Brain Abscess ; Child ; Child, Preschool ; Escherichia coli ; Female ; Humans ; Hydrocephalus ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial/epidemiology* ; Retrospective Studies ; Streptococcus agalactiae ; Streptococcus pneumoniae ; Subdural Effusion ; beta-Lactamases