Endo-beta-N-acetylglucosaminidase (ENGase) is widely distributed in various organisms. The first reported ENGase activity was detected in Diplococcus pneumoniae in 1971. The protein (Endo D) was purified and its peptide sequence was determined in 1974. Three ENGases (Endo F1-F3) were discovered in Flavobacterium meningosepticum from 1982 to 1993. After that, the activity was detected from different species of bacteria, yeast, fungal, plant, mice, human, etc. Multiple ENGases were detected in some species, such as Arabidopsis thaliana and Trichoderma atroviride. The first preliminary crystallographic analysis of ENGase was conducted in 1994. But to date, only a few ENGases structures have been obtained, and the structure of human ENGase is still missing. The currently identified ENGases were distributed in the GH18 or GH85 families in Carbohydrate-Active enZyme (CAZy) database. GH18 ENGase only has hydrolytic activity, but GH85 ENGase has both hydrolytic and transglycosylation activity. Although ENGases of the two families have similar (β/α)8-TIM barrel structures, the active sites are slightly different. ENGase is an effective tool for glycan detection andglycan editing. Biochemically, ENGase can specifically hydrolyze β‑1,4 glycosidic bond between the twoN-acetylglucosamines (GlcNAc) on core pentasaccharide presented on glycopeptides and/or glycoproteins. Different ENGases may have different substrate specificity. The hydrolysis products are oligosaccharide chains and a GlcNAc or glycopeptides or glycoproteins with a GlcNAc. Conditionally, it can use the two products to produce a new glycopeptides or glycoprotein. Although ENGase is a common presentation in cell, its biological function remains unclear. Accumulated evidences demonstrated that ENGase is a none essential gene for living and a key regulator for differentiation. No ENGase gene was detected in the genomes of Saccharomyces cerevisiae and three other yeast species. Its expression was extremely low in lung. As glycoproteins are not produced by prokaryotic cells, a role for nutrition and/or microbial-host interaction was predicted for bacterium produced enzymes. In the embryonic lethality phenotype of the Ngly1-deficient mice can be partially rescued by Engase knockout, suggesting down regulation of Engase might be a solution for stress induced adaptation. Potential impacts of ENGase regulation on health and disease were presented. Rabeprazole, a drug used for stomach pain as a proton inhibitor, was identified as an inhibitor for ENGase. ENGases have been applied in vitro to produce antibodies with a designated glycan. The two step reactions were achieved by a pair of ENGase dominated for hydrolysis of substrate glycoprotein and synthesis of new glycoprotein with a free glycan of designed structure, respectively. In addition, ENGase was also been used in cell surface glycan editing. New application scenarios and new detection methods for glycobiological engineering are quickly opened up by the two functions of ENGase, especially in antibody remodeling and antibody drug conjugates. The discovery, distribution, structure property, enzymatic characteristics and recent researches in topical model organisms of ENGase were reviewed in this paper. Possible biological functions and mechanisms of ENGase, including differentiation, digestion of glycoproteins for nutrition and stress responding were hypothesised. In addition, the role of ENGase in glycan editing and synthetic biology was discussed. We hope this paper may provide insights for ENGase research and lay a solid foundation for applied and translational glycomics.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Inertial microfluidics,as a microfluidic technology with the ability to precisely manipulate particles and cells with high throughput,has attracted widespread attention.However,challenges remain in achieving particle focusing with insensitivity to flow rates in large-scale channels,mainly due to the instability of secondary flows within the inertial microfluidic chip.This study developed a microstructure-assisted ultra-low aspect ratio spiral microchannel,which utilized the stability and acceleration of secondary flows to achieve inertial particle focusing.The research results demonstrated successful particle focusing within a 1 mm-wide spiral channel chip,for different diameter sizes(7.3 μm and 15.5 μm),within a wide range of flow rates(0.5-3 mL/min).The focusing efficiencies for these particles were measured to be above 94%and 99%,respectively.Additionally,it was observed that the particle focusing position was approximately 100 μm away from the channel walls,significantly larger than other inertial focusing chips.Consequently,by incorporating ordered microstructures within the spiral channel chip,the stability and enhancement of secondary flows were achieved,resulting in flow rate and particle size-insensitive inertial focusing.Compared to traditional methods of inertial focusing,this design had advantages of not requiring additional sheath flow operations,and boasted high throughput and ease of manufacturing.This innovative structure opened up vast prospects for the development of portable inertial microfluidic chips,and could be used in the fields such as cell analysis and detection,flow cytometry,and online sample processing.

Objective:To establish a high-performance liquid chromatography (HPLC) characteristic spectrum of Radix Actinidiae Chinensis decoction pieces, standard decoction and formula granules; To simultaneously determine the contents of index components; To study the transfer law of formula granules based on the extraction amount, content of Catechin and characteristic spectrum of standard decoction.Methods:15 batches of Radix Actinidiae Chinensis decoction pieces were collected, the standard decoction was prepared, and the extraction amount was measured. The HPLC fingerprints of decoction pieces, standard decoction and formula granules were established, and the characteristic peaks were calibrated and attributed. The content of Catechins in decoction pieces, standard decoction and formula granules was measured, and the transfer rate law was calculated. The yield rate, the common peak transmission number of fingerprints, the content and the transfer rate were the main evaluation indexes, and the law of the transmission of the magnitude value was analyzed.Results:The paste yield of 15 batches of Radix Actinidiae Chinensis standard decoction ranged from 3.9%-6.3%. A total of 4 characteristic peaks were calibrated in the feature map, and peak 2 was identified as Protocatechuic acid and peak 4 as Catechin; 6 characteristic peaks were detected in Actinidia chinensis Planchon decoction pieces, standard decoction and formula granules, and their relative retention times were all within the specified range. The content of Catechins in Radix Actinidiae Chinensis decoction pieces was 0.4%-1.4%, which was 3.8%-4.9% in formula granules. The transfer rate of decoction pieces-standard decoction was 13.6%-38.3%, and the decoction-formula granules was 15.5%-21.2%.Conclusions:The mass transfer between Radix Actinidiae Chinensis decoction pieces, standard decoction and formula granules has a good migration. The formula granules also have a good correlation and consistency with the standard decoction, which indicating that the preparation process of Radix Actinidiae Chinensis is reasonable and feasible.

Objective To investigate the nutritional status of children with cystic fibrosis(CF)and understand the correlation between malnutrition and clinical characteristics as well as lung function.Methods A retrospective analysis was performed on clinical data of CF children admitted from January 2016 to June 2023.Clinical characteristics of CF children with different nutritional statuses were compared,and the correlation between malnutrition and lung function was analyzed.Results A total of 52 CF children were included,comprising 25 boys(48％)and 27 girls(52％),aged between 7 months and 17 years.Respiratory symptoms were the predominant clinical manifestations(96％,50/52).The prevalence of malnutrition was 65％(34/52),with moderate/severe malnutrition being the most common(65％,22/34).The malnutrition group had a longer duration of illness,higher proportion of digestive system symptoms,and lower levels of serum albumin(P＜0.05).Pulmonary function parameters,including forced expiratory volume in one second as a percentage of the predicted value,ratio of forced expiratory volume in one second to forced vital capacity,forced expiratory flow at 25％of forced vital capacity exhaled,forced expiratory flow at 50％of forced vital capacity exhaled,forced expiratory flow at 75％of forced vital capacity exhaled,and maximum mid-expiratory flow as a percentage of the predicted value,were lower in the malnutrition group compared to the normal nutrition group(P＜0.05).Correlation analysis showed body mass index Z-score was positively correlated with the above six pulmonary function parameters(P＜0.05).Conclusions The prevalence of malnutrition is high in CF children and is associated with decreased lung function.CF children with higher body mass index have better lung function.Therefore,screening and evaluation of nutritional status as well as appropriate nutritional intervention should be emphasized in CF children.[Chinese Journal of Contemporary Pediatrics,2024,26(3):275-281]

Objective To explore the molecular mechanism of chronic osteomyelitis and to clarify the role of MAPK signal pathway in the pathogenesis of chronic osteomyelitis,by collecting and analyzing the transcriptional information of bone tissue in patients with chronic osteomyelitis.Methods Four cases of traumatic osteomyelitis in limbs from June 2019 to June 2020 were selected,and the samples of necrotic osteonecrosis from chronic osteomyelitis(necrotic group),and normal bone tissue(control group)were collected.Transcriptome information was collected by Illumina Hiseq Xten high throughput sequencing platform,and the gene expression in bone tissue was calculated by FPKM.The differentially expressed genes were screened by comparing the transcripts of the Necrotic group and control group.Genes were enriched by GO and KEGG.MAP3K7 and NFATC1 were selected as differential targets in the verification experiments,by using rat osteomyelitis animal model and im-munohistochemical analysis.Results A total of 5548 differentially expressed genes were obtained by high throughput sequenc-ing by comparing the necrotic group and control group,including 2701 up-regulated and 2847 down-regulated genes.The genes enriched in MAPK pathway and osteoclast differentiation pathway were screened,the common genes expressed in both MAPK and osteoclast differentiation pathway were(inhibitor of nuclear factor κ subunit Beta,IκBKβ),(mitogen-activated protein ki-nase 7,MAP3K7),(nuclear factor of activated t cells 1,NFATC1)and(nuclear factor Kappa B subunit 2,NFκB2).In rat os-teomyelitis model,MAP3K7 and NFATC1 were highly expressed in bone marrow and injured bone tissue.Conclusion Based on the transcriptome analysis,the MAPK signaling and osteoclast differentiation pathways were closely related to chronic os-teomyelitis,and the key genes IκBKβ,MAP3K7,NFATC1,NFκB2 might be new targets for clinical diagnosis and therapy of chronic osteomyelitis.

Objective:To evaluate the impact of self-crosslinked hyaluronic acid (SCH) gel on endometrium recovery after artificial abortion.Methods:A multicenter, prospective randomized controlled trial was conducted across 18 hospitals from December 2021 to February 2023, involving 382 women who underwent artificial abortion. Participants were randomly allocated to receive either treatment with SCH gel (SCH group) or no treatment (control group) in a 1∶1 ratio. The primary outcome was endometrium thickness in 14 to 18 days after the first postoperative menstruation. Secondary outcomes included changes in menstrual volume during the first postoperative menstruation, menstruation resumption within 6 postoperative weeks, time to menstruation resumption, duration of the first postoperative menstruation, and incidence of dysmenorrhea.Results:Baseline characteristics of participants were comparable between the two groups (all P>0.05), with 95.3% (182/191) in SCH group and 92.7% (177/191) in the control group completed the study. The postoperative endometrial thickness in SCH group was significantly greater than that in the control group [(9.78±3.15) vs (8.95±2.32) mm; P=0.005]. SCH group also had significantly fewer participants with reduced menstrual volume [23 cases (12.6%, 23/182) vs 31 cases (17.5%, 31/177); P=0.038]. Although SCH group experienced less dysmenorrhea during the first postoperative menstrual period, this difference was not statistically significant [28.5% (51/179) vs 37.1% (65/175); P=0.083]. Outcomes were similar between SCH group and the control group regarding the proportion of participants who resumed menstruation within 6 weeks postoperatively, time to menstruation resumption, and duration of the first postoperative menstruation ( P=0.792, 0.485, and 0.254, respectively). No serious adverse events were observed during the study period, and no adverse events were attributed to SCH gel treatment. Conclusion:The application of SCH gel after artificial abortion is safe and might aid in the recovery of the endometrium.

OBJECTIVE: To discover the relationship between matrix remodeling associated 7 (MXRA7) and acute B lymphoblastic leukemia (B-ALL), and explore the effect of MXRA7 on the biological functions of B-ALL cell line REH. METHODS: The expression of MXRA7 in blood diseases was searched and analyzed through BloodSpot database. Real-time qPCR was used to detect the expression level of MXRA7 in B-ALL cell line 697 and REH cells. Lentivirus-mediated shRNA interference technology was utilized to knock down the expression of MXRA7 in REH cells. The effects of MXRA7 on the biological functions of REH cells were studied by in vitro experiments. Cell proliferation was detected by CCK-8 assay, cell cycle was detected by PI staining, cell apoptosis was detected by Annexin V and 7-AAD staining, and the expression of apoptosis pathway related proteins was detected by Western blot. RESULTS: Database analysis showed that MXRA7 was highly expressed in B-ALL patients, and real-time qPCR results showed that MXRA7 was also highly expressed in cell lines 697 and REH cells. Knockdown of MXRA7 in REH cells inhibited the cell proliferation and increased the percentage of G₀/G₁ phase cells. After treatment with cytarabine, the apoptotic ratio was increased in MXRA7-impaired REH cells, and the activation of caspase-3 and caspase-9 were also increased. CONCLUSION Knockdown of MXRA7 can reduce the malignancy of REH cells by inhibiting the cell proliferation and increasing the sensitivity of REH cells to cytarabine. These results indicate MXRA7 may be as a novel target for the treatment of B-ALL, and the potential usefulness of MXRA7 in B-ALL deserves further investigation.
Humans ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Cytarabine ; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism*

Objective: To investigate the quality of life and associated factors in patients with coronary heart disease (CHD) in China. Methods: A cross-sectional study of 25 provinces and cities in China was performed from June to September 2020. A questionnaire was used to collect the socio-demographic and clinical information of patients with CHD, while the European Five-dimensional Quality of Life Scale (EQ-5D) was used to assess the quality of life. Multiple linear regression model was performed to analyze the associated factors. Results: The median age of the 1 075 responders was 60 (52, 67) years, and 797 (74.1%) were men. The EQ-5D and EQ-VAS indices were 0.7 (0.5, 0.8) and 60.0 (40.0, 80.0). Among the five dimensions in the quality of life scale, the frequency of anxiety/depression was the highest (59.8%), while problems in self-care was the lowest (35.8%). In the multiple linear regression model, female, increasing age, obesity, comorbidity(ies), anxiety/depression, social media channels, and receiving the CABG therapy were associated with the lower EQ-5D index (all P<0.05). In addition, increasing age, obesity, comorbidity (ies), depression, anxiety and depression, social media channels, and receiving the CABG therapy were associated with lower EQ-VAS index (all P<0.05). Conclusion: Over half of the patients with CHD in China have a low quality of life, which is related to gender, age, obesity, treatment pathway, the presence or absence of comorbidity (ies), and psychological state. In addition to managing the adverse effects of traditional socio-demographic factors on the quality of life, clinical practices should pay attention to the psychological state of patients. Moreover, establishing a WeChat group for doctor-patient communication could improve the quality of life of CHD patients.
Male ; Humans ; Female ; Quality of Life/psychology* ; Self Report ; Cross-Sectional Studies ; Coronary Disease ; Surveys and Questionnaires ; Obesity