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 lo investigate the protective effect of dihydromyricetin(DHM)against exercise-induced muscle damage(EIMD)in mice and its potential mechanism. Methods Adult male C57BL/6J mice were randomly divided into control group(CG),exercise group(EG),and exercise+100 mg/kg weightd DHM(DHM)group.The intervention lasted for four weeks,during which the animals in the EG and DHM groups were subjected to exercise training for 1 h per day.The day after the training,a 90-min treadmill exercise(slope:0 and speed:18 m/min)was conducted in both EG and DHM groups.Samples of blood and gastrocnemius muscles were harvested from the three groups 24 h after the exercise,followed by the measurement of serum creatine kinase(CK)and lactate dehydrogenase(LDH)activities,total superoxide dismutase(T-SOD)activity,malondialdehyde(MDA),and skeletal muscle mitochondrial enzyme complex Ⅰ and Ⅱ activities.Histological changes in the skeletal muscle were observed by transmission electron microscopy,and the protein expressions of mitochondrial function-related pathways were detected by Western blotting. Results Skeletal muscle morphological changes and mitochondrial damage were alleviated in the DHM group compared to those in the EG.The activities of EIMD markers CK and LDH and the level of lipid peroxidation were notably repressed and the serum T-SOD activity was enhanced after DHM intervention.Western blotting demonstrated that the expressions of sirtuin type 3(SIRT3),estrogen-related receptor alpha,and peroxisome proliferator-activated receptor-gamma coactivator-1 alpha in the skeletal muscle of mice increased after the DHM intervention. Conclusion DHM can relieve EIMD in mice,possibly by promoting the recovery of the mitochondrial structure and function in the skeletal muscle of mice after high-intensity exercise via the activation of the SIRT3 signaling pathway.

Objective To investigate the effect of Polyetheretherketone(PEEK)rod semi-rigid pedicle screw fixation sys-tem in lumbar spine non-fusion surgery.Methods A total of 74 patients with tow-level lumbar degenerative diseases who un-derwent surgery from March 2017 to December 2019 were divided into PEEK rod group and titanium rod group.In the PEEK rod group,there were 34 patients,including 13 males and 21 females,aged from 51 to 79 years old with an average of(62.4±6.8)years old;There were 1 patient of L1-L3 segments,7 patients of L2-L4 segments,20 patients of L3-L5 segments and 6 pa-tients of L4-S1 segments.In the titanium rod group,there were 40 patients,including 17 males and 23 females,aged from 52 to 81 years old with an average of(65.2±7.3)years old;There were 3 patient of L1-L3 segments,11 patients of L2-L4 segments,19 patients of L3-L5 segments and 7 patients of L4-S1 segments.The general conditions of operation,such as operation time,intraoperative blood loss,postoperative drainage was recorded.The visual analogue scale(VAS)for low back pain and Os-westry disability index(ODI)were compared in preoperatively and postoperatively(3 months,12 months and last follow-up)between two groups.The change of range of motion(ROM)was observed by flexion and extension x-ray of lumbar Results All patients successfully completed the operation.The follow-up time ranged from 22 to 34 months with an average of(26.8±5.6)months.The operative time(142.2±44.7)min and intraoperative blood loss(166.5±67.4)ml in PEEK group were lower than those in titanium group[(160.7±57.3)min、(212.8±85.4)ml](P＜0.05).There was no significant differences in postoperative drainage between the two groups(P＞0.05).At the final follow-up visit,in PEEK group and titanium group VAS of low back pain[(0.8±0.4)points vs(1.0±0.5)points],VAS for leg pain[(0.7±0.4)points vs(0.8±0.5)points]and ODI[(9.8±1.6)％vs(12.1±1.5)％]were compared with preoperative[(5.8±1.1)points vs(6.0±1.1)points],[(7.2±1.7)points vs(7.0±1.6)points],[(68.5±8.9)％vs(66.3±8.2)％]were significantly different(P＜0.05).There was no significant difference in VAS scores between the two groups at each postoperative time point(P＞0.05).At 3 months after surgery,there was no difference in ODI between the two groups(P＞0.05).There were significant differences in ODI between PEEK group and titanium rod group at 12 months[(15.5±2.1)％vs(18.4±2.4)％]and at the last follow-up[(9.8±1.6)％vs(12.1±1.5)％](P＜0.05).The total range of motion(ROM)of lumbar decreased in both groups after surgery.At 12 months after surgery and the last follow-up,the PEEK group compared with the titanium rod group,the total range of motion of lumbar was statistically significant(P＜0.05).The range of motion(ROM)of the fixed segments decreased in both groups after surgery.The ROM of the fixed segments in PEEK group decreased from(9.5±4.6)° to(4.1±1.9)° at the last follow-up(P＜0.05),which in the titanium rod group was de-creased from(9.8±4.3)°to(0.9±0.5)° at the last follow-up(P＜0.05).The range of motion(ROM)of upper adjacent segment increased in both groups,there was statistical significance in the ROM of upper adjacent segment between the two groups at 12 months after surgery and the last follow-up,(P＜0.05).There was no screw loosening and broken rods in both groups during the follow-up period.Conclusion The PEEK rod semi-rigid pedicle screw internal fixation system used in lumbar non-fusion surgery can retain part of the mobility of the fixed segment,showing comparable short-term clinical efficacy to titanium rod fu-sion.PEEK rod semi-rigid pedicle screw internal fixation system is a feasible choice for the treatment of lumbar spine degener-ative diseases,and its long-term efficacy needs further follow-up observation.

Aim To investigate the synergistic sensiti-zation effect of saikosaponin D(SSD)combined with temozolomide(TMZ)on glioblastoma cells(GBM)and its molecular mechanism.Methods The sensitiv-ity of RG-2,U251 and LN-428 GBM cell lines to SSD and TMZ was analyzed by CCK-8 method combined with HE staining,and the optimal compatible concen-tration was screened.The effect of HE staining com-bined with Hoechst fluorescence staining on the prolif-eration of GBM cell line was detected by clonal forma-tion experiment.The autophagosome formation of GBM cells was observed by monodansylcadaverine(MDC)staining.The expression and distribution of endoplas-mic reticulum stress-related factors and apoptosis and autophagy proteins were detected by Western blot and ICC.Results The sensitivity order of GBM cells to TMZ was RG-2＞U251＞LN-428.The results of com-bined administration showed the synergistic inhibitory effect of SSD combined with TMZ on proliferation of GBM cell lines,which was confirmed by cell cloning formation experiment.Compared with the TMZ group,Hoechst fluorescence staining showed a significant in-crease in the number of nuclear bright staining in the combined administration group.MDC fluorescence staining showed that there were more dense green parti-cles in the cytoplasm of SSD/TMZ plus group than that of TMZ group.Western blot results showed that com-pared with TMZ group,the expression of ER stress markers GRP78,CHOP,p-PERK and ATF6 signifi-cantly increased in SSD/TMZ group(P＜0.05).The expressions of apoptosis proteins caspase-12,caspase-9,caspase-3,cleaved caspase-3,Bax and autophagy proteins LC3 and Beclin-1 significantly increased(P＜0.05),which were verified by ICC test.Conclusions SSD can cooperate with TMZ to inhibit the prolifera-tion of GBM cells and induce apoptosis and autophagy,and enhance the sensitivity of GBM cells to TMZ by ac-tivating endoplasmic reticulum stress pathway.

Background/Aims: The histological characteristics and natural history of precirrhotic primary biliary cholangitis (PBC) with portal hypertension (PH) are unclear. Our aim was to clarify the prevalence, risk factors, and histological characteristics of precirrhotic PBC patients with PH. Methods: This retrospective study compared the clinical features, histological characteristics, and response to ursodeoxycholic acid (UDCA) between the PH and non-PH groups of precirrhotic PBC patients. Results: Out of 165 precirrhotic PBC patients, 40 (24.2%) also had PH. According to histological stage 1, 2 and 3 disease, 5.3% (1/19), 17.3% (17/98), and 45.8% (22/48) of patients also had PH, respectively. Precirrhotic PBC with PH was significantly positively correlated with bile duct loss, degree of cytokeratin 7 positivity, and degree of fibrosis in the portal area, but significantly negatively correlated with lymphoid follicular aggregation. Compared to the non-PH group, patients in the PH group showed a higher prevalence of obliterative portal venopathy, incomplete septal fibrosis, portal tract abnormalities and non-zonal sinusoidal dilatation (p<0.05). In addition, patients with PH were more likely to present with symptoms of jaundice, ascites, epigastric discomfort, a poorer response to UDCA, and more decompensation events (p<0.05). High alkaline phosphatase levels, low white blood cell counts, high Mayo scores, and high FIB-4 index values were risk factors for precirrhotic PBC with PH. Conclusions Approximately 24.2% of precirrhotic PBC patients have PH, which is histologically related to the injury of bile ducts. High alkaline phosphatase levels, low white blood cell counts, high Mayo scores, and high FIB-4 index values are associated with increased risk of precirrhotic PBC with PH.

Two undescribed terpene glycosides and two compounds were isolated from the n-butanol fraction of Alpiniae Oxyphyllae Fructus by using various chromatographic methods, including MCI Gel, Sephadex LH-20, ODS, silica gel and semi-preparative HPLC. The structures of the isolated compounds were identified by spectroscopy methods (1D, 2D NMR, UV, IR, MS, etc.), and the absolute configuration of the compound 1 was determined by ECD calculation and acid hydrolysis. Compounds 1 and 2 are new compound, and compounds 3 and 4 were isolated from Alpiniae Oxyphyllae Fructus for the first time.

Humans ; Sarcoma, Clear Cell/pathology* ; Gastrointestinal Neoplasms/pathology* ; Esophagus ; Neuroectodermal Tumors/pathology*

Humans ; Multiple Myeloma ; Nasal Cavity

ObjectiveBased on ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS^E） technique， we identified qualitatively the metabolites of aristolochic acid（AAs） in rat in order to analyze the metabolic differences between water extract of Aristolochiae fructus（AFE） and Aristolochic acid Ⅰ（AAⅠ）. MethodSD rats were selected and administered AFE（110 g·kg^-1·d^-1） or AAⅠ（5 mg·kg^-1·d^-1） by oral for 5 days， respectively. Serum， urine and feces were collected after administration. Through sample pretreatment， ACQUITY UPLC BEH C₁₈ column（2.1 mm×100 mm， 1.7 μm） was used with the mobile phase of 0.01% formic acid methanol（A）-0.01% formic acid water（B， containing 5 mmol·L^-1 ammonium acetate） for gradient elution（0-1 min， 10%B； 1-7 min， 10%-75%B； 7-7.2 min， 75%-95%B； 7.2-10.2 min， 95%B； 10.2-10.3 min， 95%-10%B； 10.3-12 min， 10%B） at a flow rate of 0.3 mL·min^-1. Positive ion mode of electrospray ionization（ESI⁺） was performed in the scanning range of m/z 100-1 200. In combination with UNIFI 1.9.4.053 system， the Pathway-MS^E was used to qualitatively analyze and identify the AAs prototype and related metabolites in biological samples（serum， urine and feces）， and to compare the similarities and differences of metabolites in rats in the subacute toxicity test between AFE group and AAⅠ group. ResultCompared with AAⅠ group， 6， 10， 13 common metabolites and 14， 20， 30 unique metabolites were identified in biological samples（serum， urine and feces） of AFE group， respectively. Moreover， the main AAs components always followed the metabolic processes of demethylation， nitrate reduction and conjugation. Compared with common metabolites in AAⅠ group， prototype components of AAⅠ in serum and most metabolic derivatives of AAⅠ［AAⅠa， aristolochic lactam Ⅰ（ALⅠ）a， 7-OHALⅠ and its conjugated derivatives］ in biological samples were significantly increased in AFE group（P<0.05， P<0.01）， except that the metabolic amount of ALⅠ in feces of AFE group was remarkably lowed than that of AAⅠ group（P<0.01）. In addition， a variety of special ALⅠ efflux derivatives were also identified in the urine and feces of the AFE group. ConclusionAlthough major AAs components in AFE all show similar metabolic rules as AAⅠ components in vivo， the coexistence of multiple AAs components in Aristolochiae Fructus may affect the metabolism of AAⅠ， and achieve the attenuating effect by increasing the metabolic effection of AAⅠ and ALⅠ.

We prepared 15 batches of Kaixin Powder benchmark samples with the decoction pieces of different batches. Further, we established the specific chromatograms and index component content determination method of Kaixin Powder benchmark samples and analyzed the peaks and similarity of the chromatograms. With sibiricose A5, sibiricose A6, polygalaxanthone Ⅲ, 3,6'-disinapoyl sucrose, ginsenoside Rb_1, β-asarone, α-asarone, and dehydropachymic acid as index components, the index component content determination method was established and 70%-130% of the mean content of each component was set as the range. The chromatograms of 15 batches of Kaixin Powder benchmark samples had a total of 22 characteristic peaks, among which 8 peaks were identified, which represented sibiricose A5, sibiricose A6, polygalaxanthone Ⅲ, 3,6'-disinapoyl sucrose, ginsenoside Rb_1, β-asarone, α-asarone, and dehydropachymic acid, respectively. The chromatograms shared the similarity of 0.992-0.999. The 15 batches of benchmark samples had sibiricose A5 of 0.34-0.55 mg·g~(-1), sibiricose A6 of 0.43-0.57 mg·g~(-1), polygalaxanthone Ⅲ of 0.12-0.19 mg·g~(-1), 3,6'-disinapoyl sucrose of 1.08-1.78 mg·g~(-1), ginsenoside Rb_1 of 0.33-0.62 mg·g~(-1), β-asarone of 2.34-3.72 mg·g~(-1), α-asarone of 0.11-0.22 mg·g~(-1), and dehydropachymic acid of 0.053-0.079 mg·g~(-1). This study established the specific chromatograms and index component content determination method of Kaixin Powder benchmark samples, and the method was simple, feasible, reproducible, and stable. This study provides a scientific basis for further research on the key chemical properties of the benchmark samples and preparations of Kaixin Powder.
Powders ; Ginsenosides ; Benchmarking ; Drugs, Chinese Herbal/chemistry* ; Sucrose ; Chromatography, High Pressure Liquid/methods*