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.Status of nutritional literacy in peritoneal dialysis patients
Wei-Wei FU ; Shan ZHANG ; Ting-Ting ZHOU ; Wen-Xin YU ; Gui-Lan LÜ
Parenteral & Enteral Nutrition 2024;31(3):172-175,183
Objective:To determine the status of nutritional literacy and its influencing factors among the peritoneal dialysis (PD) patients. Methods:The patients who underwent PD and long-term follow-up in the Department of Nephrology,General Hospital of Eastern Theater Command between January and October,2023 were enrolled in this study. The status of nutritional literacy in the patients was assessed through collecting and analyzing the data on the patients' general information,the current nutritional status,and laboratory-and dialysis-related indicators. Results:The average score of nutritional literacy in the enrolled patients were (24.49±3.35). Significant differences in nutritional literacy scoring were observed in the different patient subgroups according to the patients' educational background,dialysis time or times of receiving multidisciplinary diet guidance (all P values<0.05). The nutritional literacy levels of PD patients were negatively correlated to the concentrations of serum calcium and prealbumin,and left ventricular posterior wall thickness,and postively correlated to prealbumin level(P<0.05). Basing on multiple linear regression analysis,the times of receiving multidisciplinary diet guidance,educational background and serum prealbumin level were identified as independent influencing factors for the nutritional literacy levels in PD patients,respectively (all P values<0.05). Conclusions:The present study showed that the nutritional literacy of PD patients was in the middle level. In clinical practice,to enhance multidisciplinary diet guidance and management at the early stage of PD could contribute to improve the nutritional status of PD patients. In addition,to increase the patients' nutritional knowledge and health management ability might be also helpful for the nutritional levels of PD patients.
3.A single-center study on the safety and effectiveness of a novel non-implant interatrial shunt device
San-Shuai CHANG ; Xin-Min LIU ; Zheng-Ming JIANG ; Yu-Tong KE ; Qian ZHANG ; Qiang LÜ ; Xin DU ; Jian-Zeng DONG ; Guang-Yuan SONG
Chinese Journal of Interventional Cardiology 2024;32(8):425-433
Objective To preliminarily evaluate the safety and effectiveness of a novel non-implantable atrial shunt device based on radiofrequency ablation for the treatment of chronic heart failure(CHF).Methods This was a prospective single-arm study.From January 2023 to December 2023,five eligible CHF patients were consecutively enrolled at Beijing Anzhen Hospital,Capital Medical University,and underwent inter-atrial shunt using Shenzhen Betterway atrial shunt device.Pulmonary capillary wedge pressure(PCWP),right atrial pressure(RAP),pulmonary artery pressure(PAP),total pulmonary resistance(TPR),pulmonary vascular resistance(PVR),and pulmonary/systemic blood flow ratio(Qp/Qs)were measured using right heart catheterization before and immediately after procedure.Patients were followed up for 90 days,and echocardiography,right heart catheterization,and cardiac functional indicators were evaluated.The primary endpoint was procedural success.Secondary endpoints included clinical success,echocardiographic changes,6-minute walk distance(6MWD)changes,New York Heart Association(NYHA)class changes,Kansas city cardiomyopathy questionnaire(KCCQ)score changes,and amino-terminal probrain natriuretic peptide(NT-proBNP)level changes at 90 days.The safety endpoint was major cardiovascular and cerebrovascular adverse events and device-related adverse events.Results All five patients successfully achieved left-to-right atrial shunt.Compared with baseline,PCWP decreased significantly immediately after procedure in all five patients,with a procedural success rate of 100%.There were no significant changes in RAP,PAP,TPR,and PVR before and immediately after procedure.After 90 days follow-up,four patients had persistent left-to-right atrial shunt,and PCWP was significantly lower than baseline,with a clinical success rate of 80%.Compared with baseline,LVEF increased,left ventricular end-diastolic diameter decreased,and tricuspid annular plane systolic excursion and right ventricular fractional area change were not impaired in all five patients at 90 days.KCCQ scores and 6MWT improved,NT-proBNP decreased,and NYHA class did not change significantly.There were no deaths,rehospitalizations for heart failure,stroke-related adverse events,or device-related adverse events during the follow-up.Conclusions The novel non-implantable atrial shunt catheter can safely and effectively improve hemodynamic,echocardiographic,and cardiac functional indicators in patients with heart failure.However,larger-scale clinical studies are still needed to validate its long-term clinical effectiveness.
4.The research of a SEC-UV-RI method to determine the modifiction degree of PEG-rhGH
Yi LI ; Xiao-ming ZHANG ; Xin-yue HU ; Yue SUN ; Lü-yin WANG ; Du-yu CHEN ; Ping LÜ ; Cheng-gang LIANG ; Jing LI
Acta Pharmaceutica Sinica 2024;59(12):3367-3373
According to the requirements of the regulatory authorities, degree of modification (DP) should be included in the characterisation of the PEGylated protein drug substance, and is one of the critical quality attributes for quality control. In this study, based on the fundamental assumption that the refractive index (RI) signal and the ultraviolet (UV) signal of PEGylated protein are equal to the sum of the corresponding signal produced by the polyethylene glycol (PEG) and protein parts of the conjugates in their uncoupled state, we developed a method to determine the DP of PEGylated recombinant human growth hormone (inpegsomatropin). In this method, 20 μL of 1 mg·mL-1 human growth hormone (hGH) standard, 2 mg·mL-1 PEG reference substance and 1 mg·mL-1 drug substance solution were each injected to size exclusion chromatographic (SEC) column for separation, detected with ultraviolet and refractive index (UV-RI) detectors in series. Finally, the DP was calculated as the formula derived from the fundamental assumption. The developed SEC-UV-RI method showed good specificity, repeatability (RSD = 0.63%,
5.Introduction to revision of Technical Specification for Occupational Health Surveillance
Chen YU ; Dehong LI ; Daoyuan SUN ; Zubing WANG ; Chaoqiang JIANG ; Xunmiao ZHANG ; Yongjian YAN ; Weiming YUAN ; Yiqun XUAN ; Xin QIAO ; Yujing XIA ; Qiuhong ZHU ; Qiang HOU ; Hong WANG ; Yiwen JIANG ; Xuetao ZHANG ; Fang QI ; Xiangpei LÜ ; Huanqiang WANG
China Occupational Medicine 2023;50(2):209-216
To revise GBZ 188 Technical Specification for Occupational Health Surveillance based on national laws, regulations, standards, specifications and legal documents of occupational disease, and combination with the actual situation in China. The main modifications are as follows: the occupational health surveillance for workers exposed to toluene (xylene may implement by reference), bromopropane, methyl iodide, ethylene oxide, chloroacetic acid, indium and its compounds, coal tar, coal tarasphalt, asphalt, β-naphthylamine, dust of metal and its compounds(tin, iron, antimony, barium and its compounds), hard metal dust, erionite dust, low temperature, laser, tick-borne encephalitis virus, Borrelia burgdorferi, and human immunodeficiency virus, for scraper or grind operators, and underground workers using squatting or kneeling position, crawling position, side-lying position, or shoulder position for a long period of time are included. The emergency health screening for workers exposed to arsenic, fluorine and its inorganic compounds, and acrylamide are included. The occupational medical examination (OME) for workers exposed to amino and nitro compounds of benzene, phosgene, monomethylamine, organic fluorine and dimethyl sulfate has been adjusted and made mandatory, with corresponding assessments required upon leaving the job. The special occupational health surveillance for workers exposed to mycobacterium tuberculosis and hepatitis virus is removed. The OME conclusion of reexamination is removed, and standardize recheck/additional inspection requirements. The optional items in OME performed before, during and after leaving post are removed, but the optional items in emergency medical examination are retained. Additional OME items are added. The Guideline for OME Summary Reports is added as informative appendix, and so on. The revised GBZ 188 Technical Specification for Occupational Health Surveillance is more scientific and practical.
6.Downward referral willingness of rehabilitation patients in an urban medical group and its influencing factors
Jingyu LI ; Yun LÜ ; Yu XIN ; Shuo LI ; Sijing PENG ; Zhongxiang MI
Chinese Journal of Rehabilitation Theory and Practice 2023;29(12):1481-1488
ObjectiveTo investigate the willingness of rehabilitation patients within an urban medical group to accept downward referrals and analyze the influencing factors. MethodsFrom June to October, 2023, a survey was conducted using a simple random sampling method among neurological and orthopedic rehabilitation patients in hospitals within a specific urban medical group. The 2013 version of the Andersen Model was employed to construct a theoretical framework for the willingness of rehabilitation patients to accept downward referrals and influencing factors. Within this framework, a questionnaire was designed using a 5-point Likert scale, comprising three sections including personal characteristics, environmental features and healthcare service utilization choices, totaling 23 questions. A preliminary survey was conducted, and the questionnaire had underwent reliability and validity testing. ResultsA total of 350 questionnaires were collected, with 314 valid questionnaires. The willingness of rehabilitation patients to accept downward referrals was found to be associated with age, rehabilitation specialties, rehabilitation phases, previous experiences with downward referrals, awareness of and perceptions regarding bidirectional referral policies, and understanding and opinions about the urban medical group (χ2 > 7.755, P < 0.05). The primary influencing factors were rehabilitation specialties, rehabilitation phases, previous experiences with downward referrals and perceptions of the necessity of bidirectional referral policies (P < 0.05). ConclusionRehabilitation specialties, rehabilitation phases, previous experiences with downward referrals and perceptions of the necessity of bidirectional referral policies are the primary factors that influenced the willingness of rehabilitation patients to accept downward referrals. We should formulate targeted and focused improvement measures based on the specific circumstances and key influencing factors of rehabilitation patients within the urban medical group regarding their willingness to accept downward referrals. Continuously enhancing the proportion of patients willingness to accept downward referrals is essential for the effective implementation of bidirectional referral for rehabilitation patients.
7.Lysosomal membrane protein Sidt2 knockout induces apoptosis of human hepatocytes in vitro independent of the autophagy-lysosomal pathway.
Jiating XU ; Mengya GENG ; Haijun LIU ; Wenjun PEI ; Jing GU ; Mengxiang QI ; Yao ZHANG ; Kun LÜ ; Yingying SONG ; Miaomiao LIU ; Xin HU ; Cui YU ; Chunling HE ; Lizhuo WANG ; Jialin GAO
Journal of Southern Medical University 2023;43(4):637-643
OBJECTIVE:
To explore the regulatory mechanism of human hepatocyte apoptosis induced by lysosomal membrane protein Sidt2 knockout.
METHODS:
The Sidt2 knockout (Sidt2-/-) cell model was constructed in human hepatocyte HL7702 cells using Crispr-Cas9 technology.The protein levels of Sidt2 and key autophagy proteins LC3-II/I and P62 in the cell model were detected using Western blotting, and the formation of autophagosomes was observed with MDC staining.EdU incorporation assay and flow cytometry were performed to observe the effect of Sidt2 knockout on cell proliferation and apoptosis.The effect of chloroquine at the saturating concentration on autophagic flux, proliferation and apoptosis of Sidt2 knockout cells were observed.
RESULTS:
Sidt2-/- HL7702 cells were successfully constructed.Sidt2 knockout significantly inhibited the proliferation and increased apoptosis of the cells, causing also increased protein expressions of LC3-II/I and P62(P < 0.05) and increased number of autophagosomes.Autophagy of the cells reached a saturated state following treatment with 50 μmol/L chloroquine, and at this concentration, chloroquine significantly increased the expressions of LC3B and P62 in Sidt2-/- HL7702 cells.
CONCLUSION
Sidt2 gene knockout causes dysregulation of the autophagy pathway and induces apoptosis of HL7702 cells, and the latter effect is not mediated by inhibiting the autophagy-lysosomal pathway.
Humans
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Lysosome-Associated Membrane Glycoproteins/metabolism*
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Autophagy
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Apoptosis
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Hepatocytes
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Lysosomes/metabolism*
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Chloroquine/pharmacology*
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Nucleotide Transport Proteins/metabolism*
9.Tumor immune checkpoint therapy and the drug delivery strategies
Pei-shan LI ; Yi-xuan LIU ; Ying XIE ; Yu-xin REN ; Ming CHEN ; Gui-ling WANG ; Wan-liang LÜ
Acta Pharmaceutica Sinica 2022;57(1):13-24
Tumor immune checkpoint therapy is a clinical treatment strategy developed based on the new principle of the inhibition of negative immune regulation. In this article, the tumor immune checkpoint therapy and the drug delivery strategies were reviewed, mainly including immunity and tumor therapy, tumor immune checkpoint therapy and its mechanism of action, clinical application of tumor immune checkpoint therapy and therapeutic drugs, immune resistance of programmed cell death protein 1 (PD1)/programmed cell death ligand 1 (PDL1) treatment and countermeasures, drug delivery strategies for tumor immune checkpoint therapeutic agents, etc. As a revolutionary new immunotherapy strategy, tumor immune checkpoint therapy has shown obvious superior therapeutic efficacy in a variety types of tumor. However, tumor immune checkpoint therapy is also faced with a big challenge, namely, immunotherapy resistance. With the discovery of new mechanism, the continuous development of new therapeutic drugs and delivery strategies, tumor immune checkpoint therapy is expected to further improve the clinical efficacy of tumor.
10.Research Progress of Targeted Ultrasound Contrast Agent BR55.
Xin-Yue ZHANG ; Ke LÜ ; Jian-Chu LI ; Yu-Xin JIANG ; Meng-Su XIAO
Acta Academiae Medicinae Sinicae 2022;44(1):118-122
BR55 is an ultrasound contrast agent targeting vascular endothelial growth factor receptor 2,which can be used to detect tumor neovascularization and improve the diagnostic accuracy.Overseas researchers have used BR55 for human ultrasound molecular imaging,which showed good safety and tolerance.We reviewed the research progress on BR55 applied in the evaluation of tumor neovascularization from the composition,characteristics,animal experiments,and clinical studies of BR55.
Animals
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Contrast Media
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Humans
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Microbubbles
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Molecular Imaging/methods*
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Neovascularization, Pathologic/diagnostic imaging*
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Ultrasonography/methods*
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Vascular Endothelial Growth Factor Receptor-2/analysis*

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