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.

Protein as the allergens could lead to allergy. In addition, a widespread class of allergens were known as glycans of N-glycoprotein. N-glycoprotein contained oligosaccharide linked by covalent bonds with protein. Recently,studies implicated that allergy was associated with glycans of heterologous N-glycoprotein found in food, inhalants, insect toxins, etc. The N-glycan structure of N-glycoprotein allergen has exerted an influence on the binding between allergens and IgE, while the recognition and presentation of allergens by antigen-presenting cells (APCs) were also affected. Some researches showed thatN-glycan structure of allergen was remodeled by N-glycosidase, such as cFase I, gpcXylase, as binding of allergen and IgE partly decreased. Thus, allergic problems caused by N-glycoproteins could potentially be solved by modifying or altering the structure ofN-glycoprotein allergens, addressing the root of the issue. Mechanism of N-glycans associated allergy could also be elaborated through glycosylation enzymes, alterations of host glycosylation. This article hopes to provide a separate insight for glycoimmunology perspective, and an alternative strategy for clinical prevention or therapy of allergic diseases.

Objective To establish a sensitive,accurate and simple method for the determination of methotrexate and methotrexate polyglutamates(MTXPG2 and MTXPG3)in human erythrocytes.Methods A dual three element gradient liquid chromatograph with a fluorescence detector was used,the C18-WP column(20 mm ×4 mm,5μm)was used as the online SPE column,and the Athena C18-WP column(150 mm x4.6 mm,3 μm)was used as the analytical column.Erythrocyte lysate was precipitated with zinc sulphate-10％formic acid methanol(100:90,v/v),and postcolumn photo-oxidation of MTXPGs to fluorescent analytes using H2O2.The fluorescence excitation wavelength was 274 nm,the emission wavelength was 470 nm,the column temperature was 40 ℃,and the injection volume was 100 μL.The specificity,standard curve,lower limit of quantitation,precision,recovery and stability of the method were investigated.Results MTX,MTXPG2 and MTXPG3 had good linearity in the range of 12.5-400.0 nmol·L-1.The standard curve of MTX was y=763.8x-2 961.1(R2=0.999 5),and the extraction recovery rate was 60.7％-66.1％;the standard curve of MTXPG2 was y=1 017.8x-239.8(R2=0.998 4),and the extraction recovery rate was 67.2％-67.3％;the standard curve of MTXPG3 was y=1 069.1x-819.6(R2=0.999 4),the extraction recovery rate was 62.9％-70.1％.Intra-day precision RSD＜8.8％,inter-day precision RSD＜10.8％.Conclusion This method is accurate and reproducibility,and the online solid-phose extraction enrichment and separation of target compounds simplify the sample pretreatment steps,improve the analysis efficiency,and is suitable for detecting the concentration of MTX,MTXPG2 and MTXPG3 in erythrocytes of patients with rheumatoid arthritis.

Objective To find potential biomarkers and analyzing metabolic pathways of the treatment by honey-processed Hedysari Radix,the cecal contents of rats with spleen-Qi deficiency were used as samples for analysis.Methods Sixty male SD rats were randomly divided into blank,model,experimental and control groups.The rats in other groups except the control group were carried out by using the three-factor compound modeling method of bitter-cold diarrhea,excessive exertion and hunger and satiety disorders.Experimental group was given 12.60 g·kg-1 honey-processed Hedysari Radix;control group was given 0.63 g·kg-1 lactobacillus bifidum triplex tabletsa;control and model groups received with equal volume of distilled water for a total of 15 days.Measure body weight,anal temperature,immune organ index of rats.Ultra-pressure liquid chromatography-quadrupole-exactive-mass spectrometry technology was used to measure the levels of endogenous metabolites in cecum contents.Orthogonal partial least squares discriminant analysis and database"Kyoto Encyclopedia of Genes and Genomes"were used to identify potential differential metabolites and possible metabolic pathways.Results After the intervention,the average body weight of the experimental,control,model and blank groups was(216.87±7.85),(210.96±9.03),(159.47±5.18)and(293.51±22.98)g;anal temperature was(36.14±0.48),(35.40±0.64),(34.50±0.78)and(36.61±0.34)℃;the thymus indexes were(1.19±0.20),(1.24±0.25),(0.47±0.15)and(1.31±0.21)mg·g-1;the spleen indexes were(1.95±0.33),(2.18±0.28),(1.61±0.27)and(2.29±0.24)mg·g-1.Compared with the model group,the above indexes of the experimental group and the control group were significantly increased(all P＜0.01).A total of 14 potential biomarkers of Honey-processed Hedysari Radix in treating spleen-Qi deficiency syndrome were screened out in this study,which mainly involved amino acid metabolism such as tryptophan and glutamate,riboflavin metabolism and adenosine 5'-monophosphate-activated protein kinase metabolism.Conclusion Honey-processed Hedysari Radix can further protect the intestinal mucosal barrier and reduce the intestinal inflammatory response by improving the metabolic level of cecum contents in rats with spleen-Qi deficiency in cecum contents,thus exerting the effect of strengthening the spleen and tonifying the Qi.

Objective To explore the protective mechanism of honey-processed Hedysari Radix in regulating intestinal mucosal injury in rats with spleen qi deficiency.Methods The three-factor composite modeling method of bitter cold diarrhea,overwork and hunger and satiety disorder was used to construct a spleen qi deficiency model rats.After the model was successfully made,they were randomly divided into model group,honey-processed Hedysari Radix group and probiotic group,with 15 animals in each group.Another 15 normal rats were taken as the blank group.The honey-processed Hedysari Radix group was given 12.6 g·kg-1 water decoction of honey-processed Hedysari Radix by gavage,the probiotics group was given Bifidobacterium Lactobacillus triple viable tablets suspension at a dose of 0.625 g·kg-1,and the blank group and the model group were given the same dose of distilled water.The rats in the four groups were administered once a day for 15 days.Enzyme-linked immunosorbent assay was used to detect diamine oxidase(DAO)in serum,D-lactic acid(D-LA),secretory immunoglobulin A factor,and Western blotting was used to detect the expression levels of AMP-activated protein kinase(AMPK),zonula occludens-1(ZO-1)and occludin in colon tissues.Results The serum levels of DAO in the blank group,model group,honey-processed Hedysari Radix group and probiotic group were(138.93±9.78),(187.95±12.90),(147.21±6.92)and(166.47±3.37)pg·mL-1;the contents of D-LA were(892.23±49.17),(1 099.84±137.64),(956.56±86.04)and(989.61±51.75)μg·L-1;the contents of SIgA in colon tissues were(14.04±1.42),(11.47±2.39),(11.84±1.49)and(12.93±1.65)μg·mL-1;the relative expression levels of ZO-1 protein in colon tissues were 1.18±0.11,0.42±0.04,0.77±0.05 and 0.95±0.07;the relative expression levels of occludin protein were 1.35±0.31,0.61±0.17,1.19±0.19 and 0.88±0.13;the relative expression levels of AMPK protein were 0.91±0.02,0.35±0.09,0.74±0.08 and 0.59±0.11.Compared with the model group,there were significant differences in the serum content of DAO and D-LA,SIgA content in colon,and the content of ZO-1,occludin and AMPK protein in the honey-processed Hedysari Radix group(P＜0.01,P＜0.05).Conclusion Honey-processed Hedysari Radix can enhance the protective effect on the intestinal mucosa of rats with spleen qi deficiency by regulating the expression of related inflammatory cytokines,intestinal mucosal upper cell enzymes and tight junction proteins in rats with spleen qi deficiency.

Objective To investigate the effects of parecoxib sodium injection combined with dexmedetomidine hydrochloride injection on postoperative cognitive function and stress response in patients with osteoporotic compression fractures.Methods The patients with osteoporotic compression fractures were divided into treatment group and control group according to the treatment plan.The control group was given intravenous injection of dexmedetomidine hydrochloride injection 0.2 μg·kg-1load dose,then micro pump injection 0.2 μg·kg-1·min-1 maintenance dose,until 30 min before the end of the operation;patients in the treatment group were intravenously injected with parecoxib sodium injection 20 mg before local anesthesia and 30 min before the end of operation on the basis of the control group.The pain,sedation,hemodynamics[mean arterial pressure(MAP),heart rate(HR)],cognitive function and safety evaluation were compared between the two groups before operation(T0),2 h after operation(T1),6 h after operation(T2),12 h after operation(T3)and 24 h after operation(T4).Results There were 39 cases in the treatment group and 41 cases in the control group.Visual analogue scale(VAS)scores in treatment group and control group were(3.09±0.55)and(3.41±0.62)scores at T1;VAS scores were(3.02±0.57)and(3.35±0.48)scores at T2;VAS scores were(2.64±0.44)and(2.90±0.46)scores at T3;VAS scores were(2.02±0.41)and(2.35±0.47)scores at T4;MMSE scores were(25.28±1.57)and(24.33±1.42)scores at T2;MMSE scores were(28.16±1.01)and(27.25±0.89)scores at T4;MoCA scores were(24.63±1.60)and(23.59±1.25)scores at T2;MoCA scores were(27.20±0.97)and(26.48±0.83)scores at T4.There were statistically significant differences in the above indexes between the treatment group and the control group(all P＜0.05).Adverse drug reactions in the treatment group included bradycardia,hypotension,nausea vomiting and hypokalemia;adverse drug reactions in the control group included bradycardia,hypotension and nausea vomiting.The total incidence rates of adverse drug reactions were 12.82％and 9.76％,without statistically significant difference(P＞0.05).Conclusion Compared with using dexmedetomidine alone,parecoxib sodium combined with dexmedetomidine is beneficial for relieving postoperative pain in patients with osteoporotic compression fractures,improving postoperative cognitive function.

【Objective】 To investigate the expressions of containing CKLF like MARVEL transmembrane domain gene 6 (CMTM6) and ras protein activator like 2 (RASAL2) in prostate cancer tissues, and to analyze the relationships between the above factors and the clinicopathological characteristics and prognosis of prostate cancer patients. 【Methods】 The prostate cancer tissues and adjacent tissues of 80 prostate cancer patients admitted to Zhumadian City Center Hospital during Feb.2018 and Feb.2020 were collected.Expressions of CMTM6 and RASAL2 were detected with immunohistochemical method.The relationship between the expressions of CMTM6 and RASAL2 and the clinical pathological characteristics of prostate cancer were analyzed.The survival curve was plotted with Kaplan-Meier method.The prognostic factors were analyzed with multivariate Cox regression. 【Results】 The positive expression rate of CMTM6 in prostate cancer tissues was 67.50%, which was obviously higher than 38.75% in adjacent tissues (χ²=13.277, P<0.001).The positive expression rate of RASAL2 in prostate cancer tissues was 47.50%, which was obviously lower than 73.75% in adjacent tissues (χ²=11.546, P=0.001).The expressions of CMTM6 and RASAL2 were not related to patients’ age, tumor size and tissue differentiation (P>0.05), but to TNM staging, Gleason score, lymph node metastasis and preoperative PSA level (P<0.05).Survival curve showed that the 3-year survival rate of positive CMTM6 expression patients was 61.11% (33/54), which was obviously lower than that of negative patients, which was 88.46% (23/26) (χ²=5.940, P=0.015).The 3-year survival rate of positive RASAL2 expression patients was 81.85% (31/38), which was obviously higher than that of negative patients, which was 59.52% (25/42) (χ²=4.887, P=0.027).Cox multivariate regression showed that Gleason score, lymph node metastasis, preoperative PSA level, CMTM6, and RASAL2 were independent influencing factors of prognosis (P<0.05). 【Conclusion】 The positive expression rate of CMTM6 in prostate cancer tissues is significantly higher than that in paracancer tissues, while the positive expression rate of RASAL2 in prostate cancer tissues is significantly lower than that in paracancer tissues. Both CMTM6 and RASAL2 are closely related to the clinical pathological characteristics and prognosis of prostate cancer patients, and may provide reference for the prognosis.

Objective:To develop and validate a model to predict the risk of malnutrition in patients with nasopharyngeal carcinoma receiving concurrent chemoradiotherapy. Methods:From April 2022 to August 2023, 430 patients with nasopharyngeal carcinoma who were admitted to the department of radiotherapy of the first affiliated hospital of Guangxi medical university in Nanning were conveniently selected as the study subjects, and they were divided into the modelling group (300 cases) and the internal validation group (130 cases) in the internal validation group in the ratio of 7:3, and 61 patients with nasopharyngeal carcinoma admitted to the affiliated cancer hospital of Guangxi medical university in Nanning City were selected as the external validation group. Logistic regression was used to establish the risk prediction model and draw nomograms,Hosmer-Lemeshow, calibration curve and ROC were used to verify the goodness of fit and predictive power of the model, and clinical decision curve was used to assess the clinical utility. Results:Logistic regression analysis showed that skeletal muscle mass index, self-rated anxiety scale score, Pittsburgh sleep quality questionnaire score, Chinese diet pagoda score, regular exercise, and digestive symptom groups were the influencing factors for malnutrition in patients with nasopharyngeal carcinoma receiving concurrent chemoradiotherapy. In the modelling group, the area under the ROC curve was 0.853 (95％CI:0.81 ～ 0.89), the maximum Youden was 0.600, and the corresponding specificity was 0.764 and the sensitivity was 0.836. The Hosmer-Lemeshow test=4.040 and P=0.853 indicated that the model had good predictive ability. Calibration curve of the calibration showed that the predictive effect of the model matched actual probability well, with an average absolute error was 0.024. When the threshold probability of the clinical decision curve is 0.05 ～ 0.85, the clinical response rate is higher. The area under the operating curve of the subjects in the internal validation group was 0.891, the sensitivity was 77.36％, the specificity was 89.61％, and the practical application accuracy was 84.62％. The area under the operating curve of the subjects in the external validation group was 0.886, the sensitivity was 76.00％, the specificity was 83.33％, and the overall accuracy was 80.33％. Conclusion:The risk prediction model constructed in this study has a good effect, which can effectively predict the incidence of malnutrition in patients receiving concurrent radiotherapy and chemotherapy for nasopharyngeal carcinoma, and provide a reference for clinical staff to formulate and implement nutritional interventions.

Objective To study the in vitro expression of three phenylalanine hydroxylase(PAH)mutants(p.R243Q,p.R241C,and p.Y356X)and determine their pathogenicity.Methods Bioinformatics techniques were used to predict the impact of PAH mutants on the structure and function of PAH protein.Corresponding mutant plasmids of PAH were constructed and expressed in HEK293T cells.Quantitative reverse transcription polymerase chain reaction was used to measure the mRNA expression levels of the three PAH mutants,and their protein levels were assessed using Western blot and enzyme-linked immunosorbent assay.Results Bioinformatics analysis predicted that all three mutants were pathogenic.The mRNA expression levels of the p.R243Q and p.R241C mutants in HEK293T cells were similar to the mRNA expression level of the wild-type control(P>0.05),while the mRNA expression level of the p.Y356X mutant significantly decreased(P<0.05).The PAH protein expression levels of all three mutants were significantly reduced compared to the wild-type control(P<0.05).The extracellular concentration of PAH protein was reduced in the p.R241C and p.Y356X mutants compared to the wild-type control(P<0.05),while there was no significant difference between the p.R243Q mutant and the wild type control(P>0.05).Conclusions p.R243Q,p.R241C and p.Y356X mutants lead to reduced expression levels of PAH protein in eukaryotic cells,with p.R241C and p.Y356X mutants also affecting the function of PAH protein.These three PAH mutants are to be pathogenic.[Chinese Journal of Contemporary Pediatrics,2024,26(2):188-193]

Hip fracture in the elderly is characterized by high incidence, high disability rate, and high mortality and has been recognized as a public health issue threatening their health. Surgery is the preferred choice for the treatment of elderly patients with hip fracture. However, lower extremity deep venous thrombosis (DVT) has an extremely high incidence rate during the perioperative period, and may significantly increase the risk of patients′ death once it progresses to pulmonary embolism. In response to this issue, the clinical guidelines and expert consensuses all emphasize active application of comprehensive preventive measures, including basic prevention, physical prevention, and pharmacological prevention. In this prevention system, basic prevention is the basis of physical and pharmacological prevention. However,there is a lack of unified and definite recommendations for basic preventive measures in clinical practice. To this end, the Orthopedic Nursing Professional Committee of the Chinese Nursing Association and Nursing Department of the Orthopedic Branch of the China International Exchange and Promotive Association for Medical and Health Care organized relevant nursing experts to formulate Expert consensus on perioperative basic prevention for lower extremity deep venous thrombosis in elderly patients with hip fracture ( version 2024) . A total of 10 recommendations were proposed, aiming to standardize the basic preventive measures for lower extremity DVT in elderly patients with hip fractures during the perioperative period and promote their subsequent rehabilitation.