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*

Objective The aim of this study was to investigate the impact and mechanisms of emodin on oxidative stress response in lipopolysaccharide(LPS)-induced murine mononuclear macrophages(RAW264.7).Methods Involved the use of LPS,RAW264.7 cells,and emodin.Experimental groups included a control group,LPS(1 μg/mL)group,and LPS(1 μg/mL)+emodin(15 μmmol/L)pretreatment group.Aldehyde malondialdehyde(MDA)content,intracellular reactive oxygen species(ROS)levels,and silent information regulator 2(Sirt2)expression were evaluated at 6,12,and 18 hours after LPS exposure.Additionally,RAW264.7 cells were pretreated with Sirt2 inhibitor AGK2(20 μmol/L)followed by LPS stimulation,and the above-mentioned parameters were assessed at 6 hours.Results Compared to the control group,MDA content,ROS levels,Sirt2 mRNA,and protein expression in RAW264.7 cells in the LPS group increased at all time points(all P<0.05).At 6 and 18 hours,MDA content and ROS levels in RAW264.7 cells in the LPS+emodin group decreased significantly(all P<0.05),while at 12 hours,ROS levels were lower in the LPS group compared to the LPS+emodin group(P<0.05).Sirt2 mRNA and protein levels significantly increased at all time points(all P<0.05)compared to the LPS group.In the LPS+emodin+AGK2 group,Sirt2 mRNA and protein levels decreased,and MDA content and ROS levels increased compared to the LPS+emodin group(all P<0.05).Conclusion LPS-induced oxidative stress in RAW264.7 cells and emodin attenuate LPS-induced oxidative stress in RAW264.7 cells through Sirt2.

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.

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 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]

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates.Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity.This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes.The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes,and corresponding reference ranges will be established.The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance,with altitude gradients divided into 4 categories:800 m,1 900 m,2 400 m,and 3 500 m,with an anticipated sample size of 170 neonates per altitude gradient.This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.[Chinese Journal of Contemporary Pediatrics,2024,26(4):403-409]

AIM: To explore the correlation between the integrity of the macular microstructures and the visual outcomes before and after idiopathic macular epiretinal membrane(IMEM)surgery.METHODS: A total of 43 patients(43 eyes)with IMEM who were treated in our hospital between January 2017 and December 2019 were selected. The best corrected visual acuity(BCVA)of each patient was examined preoperatively and at 3, 6, 9mo after surgery. Moreover, metamorphopsia(M-chart)examination was given, and spectral domain-optical coherence tomography(SD-OCT)was used to measure central foveal thickness(CFT), subfoveal choroidal thickness(SFCT), the thickness of ganglion cells-inner plexiform layer(GC-IPL)and the length of interdigitation zone(IZ)defect.RESULTS: The BCVA and the metamorphopsia were gradually improved at postoperative 3, 6 and 9 mo(all P<0.05). Moreover, the BCVA was positively correlated with CFT and the length of the IZ defect(P<0.05), while it was not correlated with SFCT and the thickness of GC-IPL(P>0.05). The metamorphopsia assessment was positively correlated with the CFT at postoperative 3, 6, and 9mo(P<0.05), while it was not correlated with SFCT, the thickness of GC-IPL and the length of IZ defect(P>0.05).CONCLUSIONS: The CFT and the length of IZ defect were significantly correlated with the BCVA after IMEM surgery, which can be used as indicators to predict the recovery of visual function after IMEM surgery.

OBJECTIVE: This study assesses the impact of iodine-rich processed foods and dining places on the iodine nutritional status of children. METHODS: School-aged children (SAC) in seven provinces in China were selected by school-based multi-stage sampling. Urinary iodine, salt iodine, and thyroid volume (TVOL) were determined. Questionnaires were used to investigate dining places and iodine-rich processed foods. The water iodine was from the 2017 national survey. Multi-factor regression analysis was used to find correlations between variables. RESULTS: Children ate 78.7% of their meals at home, 15.1% at school canteens, and 6.1% at other places. The percentage of daily iodine intake from water, iodized salt, iodine-rich processed foods, and cooked food were 1.0%, 79.2%, 1.5%, and 18.4%, respectively. The salt iodine was correlated with the urinary iodine and TVOL, respectively (r = 0.999 and -0.997, P < 0.05). The iodine intake in processed foods was weakly correlated with the TVOL (r = 0.080, P < 0.01). Non-iodized salt used in processed foods or diets when eating out had less effect on children's iodine nutrition status. CONCLUSION Iodized salt remains the primary source of daily iodine intake of SAC, and processed food has less effect on iodine nutrition. Therefore, for children, iodized salt should be a compulsory supplement in their routine diet.
Humans ; Child ; Nutritional Status ; Cross-Sectional Studies ; Iodine ; Sodium Chloride, Dietary/analysis* ; China ; Water

There are 500 species of Viola(Violaceae) worldwide, among which 111 species are widely distributed in China and have a long medicinal history and wide varieties. According to the authors' statistics, a total of 410 compounds have been isolated and identified from plants of this genus, including flavonoids, terpenoids, phenylpropanoids, organic acids, nitrogenous compounds, sterols, saccharides and their derivatives, volatile oils and cyclotides. The medicinal materials from these plants boast anti-microbial, anti-viral, anti-oxidant and anti-tumor activities. This study systematically reviewed the chemical constituents and pharmacological activities of Viola plants to provide a basis for further research and clinical application.
Viola/chemistry* ; Plant Extracts/pharmacology* ; Flavonoids ; Terpenes/pharmacology* ; China