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.

OBJECTIVE: To compare clinical efficacy of tibial transverse transport (TTT) microcirculation reconstruction and periosteal distraction in treating patients with early diabetic foot(DF). METHODS: From June 2021 to June 2024, 60 patients with DF were admitted and divided into bone transport group and stretch group according to different treatment methods. There were 30 patients in bone transport group, including 16 males and 14 females;aged from 48 to 65 years old with an average of (55.59±3.78) years old;the course of disease ranged from 2 to 9 months with an average of(5.95±1.32) months;TTT microcirculation reconstruction surgery was performed. There were 30 patients in distraction group, including 17 males and 13 females;aged from 47 to 67 years old with an average of (55.24±3.81) years old;the course of disease ranged from 2 to 10 months with an average of (5.68±1.54) months;periosteal distraction surgery was performed. The skin temperature of the affected feet, the time of getting out of bed and walking after operation, the time of full weight-bearing, the wound healing time and complications were compared between two groups;the pain was evaluated by visual analogue scale (VAS) before operation and one month after operation respectively;the changes of blood flow velocity of dorsal foot arteries, ankle brachial index(ABI), epidermal growth factor (EGF), and basic fibroblast growth factor (bFGF) before and after operation at 3 months were compared between two groups. RESULTS: All patients were followed up for 3 to 4 months with an average of (3.52±0.12) months. There were no statistically significant differences in comparison of foot skin temperature, postoperative walking time, full weight-bearing time and complications between two groups (P>0.05). The wound healing time of bone transport group (61.26±7.31) days was shorter than that of distraction group (70.17±7.15) days, and the difference was statistically significant (P<0.05). Postoperative VAS at 1 month of bone transport group (2.19±0.21) was lower than that of distraction group (2.55±0.20), and the difference was statistically significant (P<0.05). At 3 months after operation, the blood flow velocity of dorsal foot artery, ankle-brachial index, EGF and bFGF in bone transport group were(34.73±4.18) cm·s^-1, (0.95±0.13), (716.61±71.13) pg·ml^-1 and (175.69±31.28) pg·ml^-1, respectively;which were higher than that of distraction group (31.86±3.23) cm·s^-1, (0.84±0.11), (677.37±70.21) pg·ml^-1, (149.26±30.13) pg·ml^-1, and the differences were statistically significant (P<0.05). There was no recurrence of ulcers in situ or at other sites in both groups during follow-up. CONCLUSION Compared with periosteal distraction, TTT microcirculation reconstruction surgery has a definite effect in the treatment of early DF. It could effectively reduce pain level, improve blood flow indicators and vascular endothelial function of the foot, and has a relatively high safety.
Humans ; Male ; Female ; Middle Aged ; Aged ; Tibia/blood supply* ; Diabetic Foot/physiopathology* ; Microcirculation ; Periosteum/surgery* ; Plastic Surgery Procedures/methods* ; Osteogenesis, Distraction

This study was aimed at understanding the detection rate,drug resistance characteristics,virulence characteris-tics,multi-locus sequence typing,and other molecular epidemic and pathogenic characteristics of Campylobacter jejuni and Campylobacter coli in children in Guangdong Province from 2020 to 2022.Anal swabs or stool samples of suspected infection cases in children from 2020 to 2022 were collected from two hospitals in Guangzhou,Guangdong Province.Campylobacter was isolated and cultured through the filtration method,and identified with a microbial mass spectrometry system;antibiotic resist-ance was analyzed with the agar dilution method;bacterial genome nucleic acids were extracted,and whole-genome sequencing was conducted;and drug resistance genes,virulence genes,multi-locus sequence typing,and phylogenetic analysis based on whole-genome single nucleotide polymorphisms were analyzed from whole-genome sequencing results.First,53 strains of Campy-lobacter were detected through continuous routine monitoring in this study,with a positive detection rate of 2.94％.Among them,Campylobacter jejuni accounted for 81.13％(43/53)and Campylobacter coli accounted for 18.87％(10/53).In addition,16 strains of Campylobacter were screened through multi-pathogen surveillance,including 11 strains of Campylobacter jejuni and 5 strains of Campylobacter coli.Drug resistance ex-periments and whole genome sequencing were conducted on 46 Campylobacter isolates,including 33 isolates of Campylobacter jejuni and 13 isolates of Campylobacter coli.The resistance rate of Campylobacter to erythromycin,a widely used clinical treatment,was21.73％(10/46);that to tetracycline was 80.43％(37/46);those to the quinolone antibiotics nalidixic acid and ciprofloxacin were 76.08％(35/46)and 71.73％(33/46)respectively;and that to chloramphenicol was lowest,at 2.17％(1/46).The drug resistance rate was generally higher for Campylobacter coli than Campylobacter jejuni,and the differences in the indicators of erythromycin,gentamicin,streptomycin,telithromycin,and clindamycin were statistically significant.A total of 30 isolates of multidrug-resistant Campylobacter were detected,including nine multidrug-resistant phenotypes.Whole-ge-nome sequence analysis indicated that 46 Campylobacter isolates carried antibiotic resistance genes for antibiotics such as quino-lones,tetracyclines,β-lactams,and aminoglycosides,and carried 128 virulence factor genes in five categories.All 46 isolates of Campylobacter were identified as 35 ST type through MLST typing,and phylogenetic analysis indicated no obvious dominant ST type.Campylobacter coli had more SNPs than Campylobacter jejuni.In conclusion,the positive detection rate of Campy-lobacter in Guangzhou City,Guangdong Province stabilized from 2020 to 2022,and the detection rate of Campylobacter jejuni was higher than that of Campylobacter coli.Campylobacter isolates were resistant to tetracyclines and quinolone,and showed a wide spectrum of multi-drug resistance,which was relatively severe among Campylobacter coli.Resistance genes and drug-resistant phenotypes were correlated and had predictive significance.The virulence genes of Campylobacter jejuni were more a-bundant than those of Campylobacter coli,possibly because of the higher detection rate and pathogenicity of Campylobacter jejuni.The phylogenetic tree showed clear branches with high genetic diversity and no clearly dominant clonal group.

Objectives: To examine the influence of adjuvant chemotherapy after radical resection on the survival of patients with intrahepatic cholangiocarcinoma(ICC) and to identify patients who may benefit from it. Methods: The clinical and pathological data of 654 patients with ICC diagnosed by postoperative pathology from December 2011 to December 2017 at 13 hospitals in China were collected retrospectively. According to the inclusion and exclusion criteria,455 patients were included in this study,including 69 patients (15.2%) who received adjuvant chemotherapy and 386 patients (84.8%) who did not receive adjuvant chemotherapy. There were 278 males and 177 females,with age of 59 (16) years (M(IQR))(range:23 to 88 years). Propensity score matching (PSM) method was used to balance the difference between adjuvant chemotherapy group and non-adjuvant chemotherapy group. Kaplan-Meier method was used to plot the survival curve,the Log-rank test was used to compare the difference of overall survival(OS) and recurrence free survival(RFS)between the two groups. Univariate analysis was used to determine prognostic factors for OS. Multivariate Cox proportional hazards models were then performed for prognostic factors with P<0.10 to identify potential independent risk factors. The study population were stratified by included study variables and the AJCC staging system,and a subgroup analysis was performed using the Kaplan-Meier method to explore the potential benefit subgroup population of adjuvant chemotherapy. Results: After 1∶1 PSM matching,69 patients were obtained in each group. There was no significant difference in baseline data between the two groups (all P>0.05). After PSM,Cox multivariate analysis showed that lymph node metastasis (HR=3.06,95%CI:1.52 to 6.16,P=0.039),width of resection margin (HR=0.56,95%CI:0.32 to 0.99,P=0.044) and adjuvant chemotherapy (HR=0.51,95%CI:0.29 to 0.91,P=0.022) were independent prognostic factors for OS. Kaplan-Meier analysis showed that the median OS time of adjuvant chemotherapy group was significantly longer than that of non-adjuvant chemotherapy group (P<0.05). There was no significant difference in RFS time between the adjuvant chemotherapy group and the non-adjuvant chemotherapy group (P>0.05). Subgroup analysis showed that,the OS of female patients,without HBV infection,carcinoembryonic antigen<9.6 μg/L,CA19-9≥200 U/ml,intraoperative bleeding<400 ml,tumor diameter>5 cm,microvascular invasion negative,without lymph node metastasis,and AJCC stage Ⅲ patients could benefit from adjuvant chemotherapy (all P<0.05). Conclusion: Adjuvant chemotherapy can prolong the OS of patients with ICC after radical resection,and patients with tumor diameter>5 cm,without lymph node metastasis,AJCC stage Ⅲ,and microvascular invasion negative are more likely to benefit from adjuvant chemotherapy.

OBJECTIVES: To compare the effects of cell lysis method and magnetic beads method in forensic DNA identification and to explore these two methods in forensic DNA identification. METHODS: The genome DNA of THP-1 cells in different quantities was extracted by the cell lysis method and magnetic beads method, and the DNA content was quantified by real-time quantitative PCR. The cell lysis method and magnetic beads method were used to type the STR of human blood with different dilution ratios. RESULTS: When the numbers of THP-1 cell were 100, 400 and 800, the DNA content extracted by cell lysis method were (1.219±0.334), (5.081±0.335), (9.332±0.318) ng, respectively; and the DNA content extracted by magnetic beads method were (1.020±0.281), (3.634±0.482), (7.896±0.759) ng, respectively. When the numbers of THP-1 cells were 400 and 800, the DNA content extracted by the cell lysis method was higher than that by the magnetic beads method. The sensitivity of cell lysis method and magnetic beads method was similar in STR typing of human blood at different dilution ratios. Complete STR typing could be obtained at 100, 300 and 500-fold dilutions of blood samples, but could not be detected at 700-fold dilution. STR typing of undiluted human blood could not be detected by cell lysis method. CONCLUSIONS The cell lysis method is easy to operate and can retain template DNA to the maximum extend. It is expected to be suitable for trace blood evidence tests.
Humans ; Forensic Medicine ; DNA/genetics* ; Real-Time Polymerase Chain Reaction ; Magnetic Phenomena ; DNA Fingerprinting/methods* ; Microsatellite Repeats

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.
Female ; Fetal Growth Retardation ; Gestational Age ; Hospitalization ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Prospective Studies ; Risk Factors

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

Objective: The relationship between serum uric acid (SUA) levels and glycemic indices, including plasma glucose (FPG), 2-hour postload glucose (2h-PG), and glycated hemoglobin (HbA1c), remains inconclusive. We aimed to explore the associations between glycemic indices and SUA levels in the general Chinese population. Methods: The current study was a cross-sectional analysis using the first follow-up survey data from The China Cardiometabolic Disease and Cancer Cohort Study. A total of 105,922 community-dwelling adults aged ≥ 40 years underwent the oral glucose tolerance test and uric acid assessment. The nonlinear relationships between glycemic indices and SUA levels were explored using generalized additive models. Results: A total of 30,941 men and 62,361 women were eligible for the current analysis. Generalized additive models verified the inverted U-shaped association between glycemic indices and SUA levels, but with different inflection points in men and women. The thresholds for FPG, 2h-PG, and HbA1c for men and women were 6.5/8.0 mmol/L, 11.0/14.0 mmol/L, and 6.1/6.5, respectively (SUA levels increased with increasing glycemic indices before the inflection points and then eventually decreased with further increases in the glycemic indices). Conclusion An inverted U-shaped association was observed between major glycemic indices and uric acid levels in both sexes, while the inflection points were reached earlier in men than in women.
Aged ; Asian Continental Ancestry Group ; Blood Glucose/analysis* ; China/epidemiology* ; Cohort Studies ; Diabetes Mellitus/blood* ; Female ; Glucose Tolerance Test ; Glycated Hemoglobin A/analysis* ; Glycemic Index ; Humans ; Male ; Middle Aged ; Uric Acid/blood*

Objective:To study the quality inspection standard of seeds of Belamcanda chinensis and establish the quality grading standard of seeds of B. chinensis. Method:The purity of seeds of B. chinensis from different producing areas was analyzed，and the 1 000-grain weight，water content，viability and germination rate of seeds of B. chinensis with different diameters were determined after diameter classification. K-means was used for cluster analysis to preliminarily formulate the quality grading standard of seeds of B. chinensis. Result:There were obvious regional differences in the size of seeds of B. chinensis. The particle size of seeds of B. chinensis of Xiaochang，Dawu and Huanggang Academy of Agricultural Sciences in Hubei Province was larger and mostly between 4.5 mm to 5.5 mm. The seeds of B. chinensis from Tuanfeng，Qujing，Yunnan，and Anguo，Hebei province had smaller particle sizes than those from the other three producing areas，which were mostly between 3.5 mm to 5.0 mm. Arils in seeds of B. chinensis were removed by 10% NaClO to effectively break seed dormancy and significantly improve the seed germination rate. On this basis，the seed diameter was taken as the main grading index，and the seed moisture content，viability，germination rate and purity were taken as important reference indexes. The quality of seeds of B. chinensis was preliminarily divided into three grades，grade Ⅰ：seed diameter≥5.5 mm，moisture content≤10%，viability≥94%，germination rate≥60%，and cleanliness≥93%；grade Ⅱ：seed diameter≥4.5 mm，moisture content≤10%，viability≥90%，germination rate≥55%，and cleanliness≥85%；and grade Ⅲ：seed diameter≥3.5 mm，moisture content≤10%，viability≥84%，germination rate≥45%，cleanliness≥80%. Conclusion:In this study，the quality grading standard of seeds of B. chinensis was preliminarily established to provide reference for the quality evaluation of seeds of B. chinensis and the breeding of improved varieties. In addition，the maturity and the storage time of seeds of B. chinensis have a greater impact on the quality of seeds，so it is recommended to select fully mature（dark black） seeds and new seeds for production.

【Objective】To explore the role of lncRNA Xist in proliferation and migration of rat bone marrow mesenchymal stem cells（BMSC）and its possible mechanism.【Methods】BMSC were isolated，cultured and identified from the femur and tibia of 3 weeks old SD female rats in vitro. SiRNAs was designed and screened to acquire a high silencing efficiency siRNA. Lipo2000 was used to transfected si- Xist and si- NC into BMSC of the experimental group（si- Xist group）and the control group（si-NC group）. BMSC proliferation capacity was determined by CCK-8 assay. The transverse and longitudinal mobility of BMSC were measured by wound healing assay and transwell migration assays. QPCR was performed to verify the silencing efficiency of lncRNA Xist and detect the expression levels of SDF- 1 and CXCR4 mRNA. Western blot was used to quantify the expression of CXCR4 protein.【Results】The P3 generation BMSC shows shuttle- like or whirlpool-like，and flow cytometry showed CD11b（-），CD34（-），CD45（-），CD44（+），CD90（+），CD105（+）. When siRNAs were used to interfere with the expression of lncRNA Xist in BMSC ，the silencing efficiency of three siRNAs was 67.92% ，68.72% and 98.32% ，respectively. CCK- 8 assay showed that the OD450 value of si- Xist group decreased compared with si-NC group at 24 h and 48 h（P < 0.001，P < 0.01，respectively）and had no statistical difference at 12 h（P > 0.05）. Wound healing assay showed that the wound healing percentage of si-Xist group was lower than that of si-NC group（P < 0.05）；and the transwell migration assay showed that，compared with si- NC group，the cells that migrated through the polycarbonate membrane were obviously decreased at 6 h（P < 0.001）. QPCR experiment showed that CXCR4 expression in si-Xist group was lower than that in si-NC group at mRNA level（P < 0.05），while SDF-1 expression showed no significant statistical difference（P > 0.05）. Western blotting confirmed that CXCR4 expression in si- Xist group was lower than that in si-NC group（P < 0.05）.【Conclusions】LncRNA Xist promotes proliferation and migration of rat BMSC by regulating CXCR4 expression.