1.Endo-beta-N-acetylglucosaminidase: Possible Functions and Mechanisms
Xin-Rong LU ; Yong-Liang TONG ; Wei-Li KONG ; Lin ZOU ; Dan-Feng SHEN ; Shao-Xian LÜ ; Rui-Jie LIU ; Shao-Xing ZHANG ; Yu-Xin ZHANG ; Lin-Lin HOU ; Gui-Qin SUN ; Li CHEN
Progress in Biochemistry and Biophysics 2024;51(5):985-999
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.
2.Nimbolide targets RNF114 in treatment of mouse model of acute pneumonia caused by Staphylococcus aureus
Hui SUN ; Tian TIAN ; Tingrong XIONG ; Quanming ZOU ; Xiaokai ZHANG ; Xian YANG ; Yu WANG
Journal of Army Medical University 2024;46(12):1353-1360
Objective To explore the mechanism which drives nimbolide(NIM)in treating acute pneumonia caused by Staphylococcus aureus(S.auteus).Methods A mouse model of acute pneumonia caused by S.auteus was constructed through endotracheal intubation.After NIM treatment,the survival rate was observed,the amount of bacteria in the lung was tested by plate culture,and the expression of inflammatory cytokines in the lung tissues was detected with ELISA.After primary cultured peritoneal macrophages(PM)were infected with S.auteus,the effect of NIM on the expression of inflammatory cytokines and activation of inflammatory pathway were studied with ELISA and Western blotting,respectively.The effect of RNF114 knockdown by lentiviral shRNA infection on inflammation responses in PM was explored with ELISA and Western blotting.Results Acute infection of S.auteus in the lung could cause acute death in the mice,while NIM treatment significantly improved the survival rate and down-regulated the levels of inflammatory cytokines in the lung.However,it had no effect on the lung colonization of S.auteus in the short term.The results of in vitro experiments indicated that NIM may regulate RNF114 function to down-regulate the phosphorylation level of ERK,inhibit the activation of MAPK pathway,and thus suppress the expression of inflammatory cytokines.Conclusion NIM may inhibit the activation of MAPK pathway by regulating the function of RNF114,and thus suppress the expression of inflammatory cytokines in the lung,and finally inhibit the death of mice with acute pulmonary hyperinflammation caused by S.auteus.
3.Necessity of slit-lamp training during ophthalmology clerkships from the perspective of medical students
Xuan-Wei LIANG ; Yu-Xian ZOU ; Shu LIU ; Zi-Wei MENG ; Xin-Yue YU ; Ye-Hong ZHUO ; Rong-Xin CHEN
International Eye Science 2023;23(1):4-9
AIM: To evaluate the necessity of slit-lamp biomicroscopy(referred to here as “slit-lamp”)training from the student's perspective and reach a consensus on slit-lamp training in medical students during ophthalmology clerkship.METHODS: A controlled before-after clerkship study was performed on 117 students of the class of 2017 enrolled in clinical medicine at Sun Yat-sen University. All medical students underwent slit-lamp training during ophthalmology clerkship. We evaluated the students' cognition, perceived need and recommendations for slit-lamp teaching, using a self-completed questionnaire survey and compared the students' scores in these aspects before and after their ophthalmology clerkships. Additionally, the efficiency of slit-lamp training was evaluated by subjective student assessment after the ophthalmology clerkship. Each item was scored on a five-point Likert Scale. Statistical analysis was performed by IBM SPSS(Version 20.0; SPSS Inc., Chicago, IL, USA).RESULTS: A total of 116(99.1%)medical students completed the survey. The average score before clerkship was 19.99±3.03, which indicated a high level of cognition regarding slit-lamp utility; However, this score significantly increased to 22.97±2.37 after clerkship(P<0.001). The average score regarding perceived need was also higher for post-clerkship students than for pre-clerkship students(24.62±3.15 vs. 23.60±2.36, P=0.009). Moreover, 86.2% of post-clerkship students reported that hands-on slit-lamp practice could help promote clerkship quality. More than three-quarters of the surveyed students tended to agree that slit-lamp practice time should be increased(76.7% and 77.6% before and after clerkship, respectively).CONCLUSION: A hands-on approach to slit-lamp training is more favored by medical students in ophthalmology clerkships, and this training should be recommended in ophthalmology clerkships given its potential usefulness for improving clerkship quality.
5.A new form of familial platelet disorder caused by germline mutations in RUNX1 in a pedigree.
Jun GUAN ; Lan Lan WANG ; Chun Yan WANG ; Xian Min ZHU ; Hua Zhou SHUAI ; Xue YI ; Liang ZOU ; Dan YU ; Hui CHENG
Chinese Journal of Internal Medicine 2023;62(4):393-400
Objective: To investigate the clinical and biological characteristics of familial platelet disorder (FPD) with germline Runt-related transcription factor (RUNX) 1 mutations. Methods: Patients diagnosed with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) with RUNX1 mutations from February 2016 to December 2021 in Wuhan No.1 Hospital underwent pedigree analysis and were screened for gene mutations (somatic and germline). Patients diagnosed with FPD with germline RUNX1 mutations were enrolled and evaluated in terms of clinical characteristics and biological evolution. Bioinformatics analysis was used to assess the pathogenicity of mutations and to analyze the effect of mutated genes on the function of the corresponding protein. Results: Germline RUNX1 mutations were detected in three out of 34 patients suffering from MDS/AML who had RUNX1 mutations. A pedigree of FPD with RUNX1 (RUNX1-FPD) c.562A>C and RUNX1 c.1415T>C mutations was diagnosed, and the mutations were of patrilineal origin. Bioinformatics analysis indicated that the locus at positions 188 and 472 in the AML-1G type of RUNX1 was highly conserved across different species, and that variations might influence functions of the proteins. The mutations were evaluated to be highly pathogenic. Of the nine cases with germline RUNX1 mutations: two patients died due AML progression; one case with AML survived without leukemia after transplantation of hemopoietic stem cells; four patients showed mild-to-moderate thrombocytopenia; two cases had no thrombocytopenia. During the disease course of the proband and her son, mutations in RUNX1, NRAS and/or CEBPA and KIT appeared in succession, and expression of cluster of differentiation-7 on tumor cells was enhanced gradually. None of the gene mutations correlated with the tumor were detected in the four cases not suffering from MDS/AML, and they survived until the end of follow-up. Conclusions: RUNX1-FPD was rare. The mutations c.562A>C and c.1415T>C of RUNX1 could be the disease-causing genes for the family with RUNX1-FPD, and these mutations could promote malignant transformation. Biological monitoring should be carried out regularly to aid early intervention for family members with RUNX1-FPD.
Humans
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Female
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Germ-Line Mutation
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Core Binding Factor Alpha 2 Subunit/genetics*
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Pedigree
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Blood Platelet Disorders/complications*
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Leukemia, Myeloid, Acute/genetics*
6.Clinical features and prognosis of juvenile myelomonocytic leukemia: an analysis of 63 cases.
Wen-Yu YANG ; Li-Peng LIU ; Fang LIU ; Ben-Quan QI ; Li-Xian CHANG ; Li ZHANG ; Xiao-Juan CHEN ; Yao ZOU ; Yu-Mei CHEN ; Ye GUO ; Xiao-Fan ZHU
Chinese Journal of Contemporary Pediatrics 2023;25(3):265-271
OBJECTIVES:
To investigate the clinical features of juvenile myelomonocytic leukemia (JMML) and their association with prognosis.
METHODS:
Clinical and prognosis data were collected from the children with JMML who were admitted from January 2008 to December 2016, and the influencing factors for prognosis were analyzed.
RESULTS:
A total of 63 children with JMML were included, with a median age of onset of 25 months and a male/female ratio of 3.2∶1. JMML genetic testing was performed for 54 children, and PTPN11 mutation was the most common mutation and was observed in 23 children (43%), among whom 19 had PTPN11 mutation alone and 4 had compound PTPN11 mutation, followed by NRAS mutation observed in 14 children (26%), among whom 12 had NRAS mutation alone and 2 had compound NRAS mutation. The 5-year overall survival (OS) rate was only 22%±10% in these children with JMML. Of the 63 children, 13 (21%) underwent hematopoietic stem cell transplantation (HSCT). The HSCT group had a significantly higher 5-year OS rate than the non-HSCT group (46%±14% vs 29%±7%, P<0.05). There was no significant difference in the 5-year OS rate between the children without PTPN11 gene mutation and those with PTPN11 gene mutation (30%±14% vs 27%±10%, P>0.05). The Cox proportional-hazards regression model analysis showed that platelet count <40×109/L at diagnosis was an influencing factor for 5-year OS rate in children with JMML (P<0.05).
CONCLUSIONS
The PTPN11 gene was the most common mutant gene in JMML. Platelet count at diagnosis is associated with the prognosis in children with JMML. HSCT can improve the prognosis of children with JMML.
Child
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Humans
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Male
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Female
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Child, Preschool
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Leukemia, Myelomonocytic, Juvenile/therapy*
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Prognosis
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Genetic Testing
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Mutation
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Hematopoietic Stem Cell Transplantation
7.Association Between Dietary Knowledge and Food Preferences in Residents Aged 18 and Over in China Based on Latent Class Analysis.
Zhen-Xin MA ; Wei-Ye CHEN ; Yu-Xian KUANG ; Yi-Ying ZHENG ; Ke-Yuan LU ; Gao-Yong ZOU ; Ding ZENG ; Li LIU
Acta Academiae Medicinae Sinicae 2023;45(5):730-736
Objective To investigate the food preferences and explore the potential association between dietary knowledge and food preferences in residents aged 18 and over in China,so as to provide a basis for promoting healthy diets.Methods The latent class analysis was carried out with the 2015 cross-sectional data of China health and nutrition survey to categorize the food preferences among 8 783 residents aged 18 and over.Multinomial Logistic regression was adopted to assess the association between and dietary knowledge and food preferences.Results The food preferences of the residents aged 18 and over in China were classified into preference for less vegetable(3.28%),lack of preference(11.20%),diverse preferences(4.19%),and preference for healthy diets(81.33%).The proportion of the adults with dietary knowledge was 36.87%(3 238/8 783).The dietary knowledge varied in the adults with different food preferences(all P<0.001).After adjusting for gender,age,urban and rural distribution,education background,and annual household income,for each point increase in the dietary knowledge score,there was an estimated reduction of 22% in the probability of preferring less vegetables(OR=0.78,95%CI=0.76-0.80, P<0.001),13% in the probability of lacking preference(OR=0.87,95%CI=0.86-0.89, P<0.001),and 3% in the probability of having diverse preferences(OR=0.97,95%CI=0.94-1.00, P=0.030).Compared with those lacking dietary knowledge,the individuals with dietary knowledge had a 77% less probability of preferring less vegetables(OR=0.23,95%CI=0.16-0.32, P<0.001),a 55% less probability of lacking preference(OR=0.45,95%CI=0.39-0.53, P<0.001),and a 23% less probability of having diverse preferences(OR=0.77,95%CI=0.61-0.96, P=0.023).Conclusions The residents aged 18 and over in China presented four food preferences,including preference for less vegetables,lack of preference,diverse preferences,and preference for healthy diets,the last of which had the highest proportion.The individuals with lower levels of dietary knowledge have higher probability of preferring unhealthy food.
Adult
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Humans
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Adolescent
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Food Preferences
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Latent Class Analysis
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Cross-Sectional Studies
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Diet
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Nutrition Surveys
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China
8.Comparison on Performance of Quantitative Ultrasound and Dual-Energy X-ray Absorptiometry in Evaluating Bone Health of Adults Aged 18-40 Years.
Yu-Xian KUANG ; Hong CHENG ; Yi-Ying ZHENG ; Wei-Ye CHEN ; Zhen-Xin MA ; Gao-Yong ZOU ; Ding ZENG ; Jie MI ; Li LIU
Acta Academiae Medicinae Sinicae 2023;45(5):737-742
Objective To compare the consistency of quantitative ultrasound(QUS)and dual-energy X-ray absorptiometry(DXA)in measuring bone mineral density(BMD)of adults aged 18-40 years in Guangzhou and evaluate the diagnostic value of QUS for identifying low bone mass.Methods DXA was employed to measure the BMD and QUS to measure the speed of sound(SOS)in 731 participants.The Bland-Altman analysis was performed to evaluate the consistency of Z scores between SOS and BMD.With the BMD Z ≤-2.00 as the diagnostic criterion for low bone mass,the receiver operating characteristics curve of QUS was established,and the area under the curve(AUC)and the sensitivity,specificity,and correct diagnostic index for the optimal cut-off of SOS Z score were calculated.Results The results of Bland-Altman analysis showed that the mean differences in the Z scores of SOS and BMD in males and females were 1.27(-0.94 to 3.47)and 0.93(-1.33 to 3.18),respectively.The AUC of SOS Z score in the diagnosis of low bone mass in males and females was 0.734(95%CI=0.380-0.788)and 0.679(95%CI=0.625-0.732),respectively.In males,the optimal cut-off of SOS Z score for low bone mass was -0.35,with the sensitivity,specificity,and correct diagnostic index of 64.1%,68.6%,and 0.327,respectively.In females,the optimal cut-off value of SOS Z scores for low bone mass was -1.14,with the sensitivity,specificity,and correct index of 73.9%,54.8%,and 0.285,respectively.Conclusion QUS and DXA show poor consistency in the diagnosis of BMD in the adults aged 18-40 years in Guangzhou,while QUS demonstrates an acceptable value in identifying low bone mass.
Male
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Female
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Adult
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Humans
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Absorptiometry, Photon/methods*
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Bone Density
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Ultrasonography
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Bone and Bones
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ROC Curve
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Sensitivity and Specificity
9.Quality of moxa with different leaf-to-moxa ratios based on correlation analysis of thermogravimetric properties, cellulose content, and microscopic characteristics of non-secretory trichomes.
Bing YI ; Li-Ping KANG ; Xin-Yu ZHAO ; Chi ZHANG ; Xin ZOU ; Liu-Jia CHAN ; Hong-Mei LI ; Xian-Zhang HUANG ; Li-Chun ZHAO ; Yuan ZHANG
China Journal of Chinese Materia Medica 2023;48(18):4950-4958
The quality of moxa is a key factor affecting the efficacy of moxibustion. Traditional moxa grades are evaluated by the leaf-to-moxa ratio, but there is a lack of support from scientific data. Scanning electron microscopy(SEM), Image Pro Plus, Van Soest method, and stimultaneous thermal analysis(TGA/DSC) were used to characterize the scientific implication of the combustion differences between moxa with different leaf-to-moxa ratios(processed by crusher). The results showed that the median lengths from non-secretory trichomes(NSTs) of natural NSTs and moxa with leaf-to-moxa ratios of 3∶1, 5∶1, 10∶1, and 15∶1 were 542.46, 303.24, 291.18, 220.69, and 170.61 μm, respectively. The cellulose content of moxa increased significantly(P<0.05) with the increase in leaf-to-moxa ratio and the combustion parameters(T_i, t_i, D_i, C,-R_p,-R_v, S, D_b, and J_(total)) all showed an increasing trend. The correlation results showed that the burning properties of moxa(T_i,-R_v, t_i, and J_2) were significantly and positively correlated with cellulose content. NSTs with a length of 1-200 μm were significantly and positively correlated with J_2. NSTs with a length of 200-600 μm were significantly and positively correlated with J_1, T_(peak2), T_(peak1), and-R_v, and negatively correlated with J_(total), T_b, and t_b. As the leaf-to-moxa ratio increases, the NSTs in the moxa become shorter and the cellulose content increases, which is more conducive to ignition performance, heat release, and a milder, longer-lasting burn. The "NSTs-cellulose-TGA/DSC" quantitative evaluation method scientifically reveals the scientific connotation of the combustion of moxa with different leaf-to-moxa ratios and provides a scientific basis for the establishment of quality evaluation methods for moxa with different leaf-to-moxa ratios.
Trichomes
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Moxibustion
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Hot Temperature
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Plant Leaves

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