Objectiveβ‑Site APP cleaving enzyme 1 (BACE1) is a rate-limiting enzyme involved in the formation of amyloid plaques in Alzheimer’s disease (AD), and its expression and activity play a crucial role in the development of AD. The interacting protein of BACE1 can directly or indirectly regulate BACE1 in the transcription, translation, modification, intracellular transport and other links of BACE1 by directly binding, indirectly binding, and participating in various cell signal transduction pathways, so as to participate in the occurrence of AD and the process of disease. This study aimed to screen and validate the interacting proteins of BACE1, providing new insights into the mechanisms of amyloid plaque formation. MethodsCo-immunoprecipitation (Co-IP) and mass spectrometry (MS) were used to enrich and identify BACE1 interacting proteins in the hippocampus of wild type (WT) mice and AD model mice. For candidate BACE1 interacting proteins, GO enrichment analysis and KEGG pathway enrichment analysis were used to explore the subcellular localization, molecular function, participating biological processes and participating signaling pathways of BACE1 interacting proteins. The protein-protein interaction (PPI) network of BACE1 was further constructed to explore the potential proteins interacting with BACE1. By searching the mouse genomeinformation (MGI) website and NCBI database, the more reliable proteins among the potential BACE1 interacting proteins were screened. Co-IP assay and immunofluorescence confocal technology were used to preliminarily verify the interaction between the proteins, and the changes in protein expression levels of the interacting proteins in AD cell models were explored. ResultsA total of 614 differentially expressed proteins interacting with BACE1 were identified in AD group. GO enrichment analysis showed that the BACE1 interacting proteins in the AD group were mainly located in membrane organelles such as Golgi apparatus, endoplasmic reticulum, endosome, lysosome and vesicles, which had molecular functions such as ion channel regulation, protein kinase activity, transcription factor binding and passive transmembrane transporter activity. It is mainly involved in the biological processes of immune response regulation cell surface receptor signaling pathway, targeting Golgi vesicles transport, circadian rhythm regulation, Purkinje cell layer development, etc. KEGG analysis showed that BACE1 interacting proteins in AD were mainly involved in the PI3K-Akt signaling pathway, mTOR signaling pathway and other neurodegenerative disease-related pathways. The PPI network of BACE1 showed that a total of 12 proteins were identified as high confidence binding proteins, including PRNP, APOE, SYP, NSF, NUMB, SNAP91, HSP90aa1, UCHL1, BIN1, SNX27, Rheb, Ap2m1, of which, NSF, NUMB, SNAP91, HSP90aa1 were newly identified candidate proteins. After further verification, we found that NSF not only interacts with BACE1, but also interacts with amyloid precursor protein (APP), the substrate of BACE1, and the expression level of NSF is up-regulated in the AD cell model constructed by Aβ₄₂ induction. ConclusionBACE1 binding proteins participate in multiple AD-associated biological processes and signal pathways. NSF is a newly identified BACE1 binding protein that interacts with BACE1, and the protein expression level of NSF is up-regulated in the AD cell model. It is predicted that the interaction between NSF and BACE1 is involved in regulating the course of AD, providing a new target and direction for the study of the mechanism of AD.

Objective To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty(TKA).Methods From February 2023 to July 2023,26 patients with unilateral knee osteoarthritis(KOA)were treated with TKA,including 4 males and 22 females,aged from 57 to 85 years old with an average of(67.58±6.49)years old;body mass in-dex(BMI)ranged from 18.83 to 38.28 kg·m-2 with an average of(26.43±4.15)kg·m-2;14 patients on the left side,12 pa-tients on the right side;according to Kellgren-Lawrence(K-L)classification,6 patients with grade Ⅲ and 20 patients with grade Ⅳ;the courses of disease ranged from 1 to 14 years with an average of(5.54±3.29)years.Images and videos of standing up and walking,walking side shot,squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation.The human posture estimation framework OpenPose were used to analyze stride frequency,step length,step length,step speed,active knee knee bending angle,stride length,double support phase time,as well as maximum hip flexion angle and maximum knee bending angle on squatting position.Western Ontario and McMaster Universities(WOMAC)arthritis index and Knee Society Score(KSS)were used to evaluate clinical efficacy of knee joint.Results All patients were followed up for 5 to 7 weeks with an average of(6.00±0.57)weeks.The total score of WOMAC decreased from(64.85±11.54)before op-eration to(45.81±7.91)at 6 weeks after operation(P＜0.001).The total KSS was increased from(101.19±9.58)before opera-tion to(125.50±10.32)at 6 weeks after operation(P＜0.001).The gait speed,stride frequency and stride length of the affected side before operation were(0.32±0.10)m·s-1,(96.35±24.18)steps·min-1,(0.72±0.14)m,respectively;and increased to(0.48±0.11)m·s 1,(104.20±22.53)steps·min-1,(0.79±0.10)m at 6 weeks after operation(P＜0.05).The lower limb support time and active knee bending angle decreased from(0.31±0.38)sand(125.21±11.64)° before operation to(0.11±0.04)s and(120.01±13.35)° at 6 weeks after operation(P＜0.05).Eleven patients could able to complete squat before operation,13 patients could able to complete at 6 weeks after operation,and 9 patients could able to complete both before operation and 6 weeks after operation.In 9 patients,the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation,and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation.Conclusion Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of pa-tients'gait.Knee pain of KOA was relieved and the function was improved,the supporting ability of the affected limb was im-proved after TKA,and the patient's stride frequency,stride length and stride speed were improved,and the overall movement rhythm of both lower limbs are more coordinated.

The global COVID-19 coronavirus pandemic has infected over 109 million people, leading to over 2 million deaths up to date and still lacking of effective drugs for patient treatment. Here, we screened about 1.8 million small molecules against the main protease (M^pro) and papain like protease (PL^pro), two major proteases in severe acute respiratory syndrome-coronavirus 2 genome, and identified 1851M^pro inhibitors and 205 PL^pro inhibitors with low nmol/l activity of the best hits. Among these inhibitors, eight small molecules showed dual inhibition effects on both M^pro and PL^pro, exhibiting potential as better candidates for COVID-19 treatment. The best inhibitors of each protease were tested in antiviral assay, with over 40% of M^pro inhibitors and over 20% of PL^pro inhibitors showing high potency in viral inhibition with low cytotoxicity. The X-ray crystal structure of SARS-CoV-2 M^pro in complex with its potent inhibitor 4a was determined at 1.8 Å resolution. Together with docking assays, our results provide a comprehensive resource for future research on anti-SARS-CoV-2 drug development.
Humans ; Antiviral Agents/chemistry* ; COVID-19 ; COVID-19 Drug Treatment ; High-Throughput Screening Assays ; Molecular Docking Simulation ; Protease Inhibitors/chemistry* ; SARS-CoV-2/enzymology* ; Viral Nonstructural Proteins

OBJECTIVE: To explore the genotyping characteristics of human fecal Escherichia coli( E. coli) and the relationships between antibiotic resistance genes (ARGs) and multidrug resistance (MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related data. METHODS: Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs, multilocus sequence typing (MLST), and polymorphism trees were analyzed using whole-genome sequencing data (WGS). RESULTS: This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal (49/70) and healthy groups (15/24). CONCLUSION We developed a random forest (RF) prediction model of TEM.1 + baeR + mphA + mphB + QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers.
Humans ; Escherichia coli/genetics* ; Escherichia coli Infections/epidemiology* ; Multilocus Sequence Typing ; Genotype ; Beijing ; Drug Resistance, Multiple, Bacterial/genetics* ; Anti-Bacterial Agents/pharmacology* ; Diarrhea ; Microbial Sensitivity Tests

This study aimed to explore the correlation between rhizosphere soil microorganisms of wild Arnebia euchroma and the content of medicinal components to provide guidance for the selection of the ecological planting base. The total DNA of rhizosphere soil microorganisms of wild A. euchroma was extracted, and the microbial community structure of rhizosphere soil microorganisms was analyzed by IlluminaMiseq high-throughput sequencing technology. The content of total hydroxynaphthoquinone pigment and β,β'-dimethylacrylalkannin in medicinal materials was determined by high-performance liquid chromatography(HPLC). The physicochemical pro-perties of rhizosphere soil of wild A. euchroma in main producing areas were determined, and the correlation of soil microbial abundance with index component content and soil physicochemical properties was analyzed by SPSS software. The results showed that the species composition of rhizosphere fungi and bacteria in A. euchroma from different habitats was similar at the phylum and genus levels, but their relative abundance, richness index(Chao1), and community diversity(Simpson) index were different. Correlation analysis showed that the content of available phosphorus in soil was positively correlated with the content of total hydroxynaphthoquinone pigment and β,β'-dimethylacrylalkannin, and the abundance of five fungal genera such as Solicoccozyma and six bacterial genera such as Pseudo-nocardia and Bradyrhizobium was positively correlated with the content of medicinal components in medicinal materials. The abundance of Bradyrhizobium was significantly positively correlated with the content of β,β'-dimethylacrylalkanin. The abundance of fungi such as Archaeorhizomyces was significantly positively correlated with the content of available phosphorus in rhizosphere soil, and Bradyrhizobium was significantly negatively correlated with soil pH. Therefore, the abundance of fungi and bacteria in the rhizosphere of A. euchroma has a certain correlation with the medicinal components and the physicochemical properties of the rhizosphere soil, which can provide a scientific basis for the selection of ecological planting bases in the later stage.
Rhizosphere ; Soil Microbiology ; Bacteria/genetics* ; Phosphorus ; Soil ; Boraginaceae

OBJECTIVE: To observe the effect of fire needling on psoriasis-like lesion and the signal transducer and activator of transcription 3 (STAT3) pathway in mice and compare the therapeutic effect between different interventions of fire needling therapy (surrounding technique of fire needling, fire needling at "Dazhui" [GV 14] and "Zusanli" [ST 36]). METHODS: Thirty male BALB/c mice were randomized into a blank group, a model group, a dexamthasone group, a surrounding technique group and an acupoint group, 6 mice in each one. Except the blank group, the mice in the rest groups were established as psoriasis-like lesion model by topical application with imiquimod cream, once daily, consecutively for 8 days. From day 4 to day 8, in the dexamthasone group, gastric infusion with 0.2 mL dexamthasone was administered, once daily. On day 4, 6 and 8, in the surrounding technique group, fire needling was exerted around the skin lesion; and fire needling was applied to "Dazhui" (GV 14) and "Zusanli" (ST 36) in the acupoint group, once a day. The changes in skin lesion on the dorsal parts of mice were observed in each group to score the psoriasis area and severity index (PASI). Using HE staining, the dermal morphological changes and epidermal thickness were observed in the mice of each group. The positive expression of proliferating cell-associated antigen Ki-67 was determined by immunofluorescence. Immunohistochemistry method was used to determine the expressions of , and T cells of skin tissue in each group. Using real-time PCR, the expressions of interleukin (IL)-17, IL-22, tumor necrosis factor α(TNF-α) mRNA were determined. Western blot method was adopted to determine the protein expressions of STAT3 and p-STAT3 in skin tissue in each group. RESULTS: Compared with the blank group, the scores of each item and the total scores of PASI, as well as the epidermal thickness were all increased in the mice of the model group (P<0.01). Except for the erythema scores of the dexamethasone group and the surrounding technique group, the scores of each item and the total scores of PASI, as well as the epidermal thickness were all decreased in each intervention group as compared with the model group (P<0.01). The infiltration scores and the total scores in the dexamethasone group and the acupoint group were lower than those in the surrounding technique group respectively (P<0.01, P<0.05). In comparison with the blank group, Ki-67 positive cell numbers and the numbers of , and T cells in skin tissue were increased in the mice of the model group (P<0.01). Ki-67 positive cell numbers and the numbers of , and T cells were reduced in each intervention group as compared with the model group (P<0.01), and the numbers of and T cells in the acupoint group were less than the surrounding technique group (P<0.01). Compared with the blank group, the mRNA expressions of IL-17, IL-22 and TNF-α and the ratio of p-STAT3 to STAT3 were all increased in the model group (P<0.01). The mRNA expressions of IL-17, IL-22 and TNF-α and the ratio of p-STAT3 to STAT3 were all decreased in each intervention group as compared with the model group (P<0.01, P<0.05). The mRNA expressions of IL-17, IL-22 and TNF-α in the acupoint group, as well as mRNA expression of IL-17 in the surrounding technique group were all lower than the dexamethasone group (P<0.01), while, the mRNA expression of IL-22 in the acupoint group was lower than the surrounding technique group (P<0.01). CONCLUSION Fire needling therapy improves skin lesion severity in imiquimod induced psoriasis-like lesion of the mice, which is probably related to the inhibition of STAT3 pathway activation and the decrease of Th17 inflammatory factors expression. The systemic regulation of fire needling at "Dazhui" (GV 14) and "Zusanli" (ST 36) is superior to the local treatment.
Animals ; Dexamethasone/therapeutic use* ; Imiquimod/metabolism* ; Interleukin-17/metabolism* ; Ki-67 Antigen/metabolism* ; Male ; Mice ; Mice, Inbred BALB C ; Psoriasis/drug therapy* ; RNA, Messenger/metabolism* ; STAT3 Transcription Factor/pharmacology* ; Skin/pathology* ; Tumor Necrosis Factor-alpha/metabolism*

OBJECTIVES: To investigate the incidence of extrauterine growth retardation (EUGR) and its risk factors in very preterm infants (VPIs) during hospitalization in China. METHODS: A prospective multicenter study was performed on the medical data of 2 514 VPIs who were hospitalized in the department of neonatology in 28 hospitals from 7 areas of China between September 2019 and December 2020. According to the presence or absence of EUGR based on the evaluation of body weight at the corrected gestational age of 36 weeks or at discharge, the VPIs were classified to two groups: EUGR group (n=1 189) and non-EUGR (n=1 325). The clinical features were compared between the two groups, and the incidence of EUGR and risk factors for EUGR were examined. RESULTS: The incidence of EUGR was 47.30% (1 189/2 514) evaluated by weight. The multivariate logistic regression analysis showed that higher weight growth velocity after regaining birth weight and higher cumulative calorie intake during the first week of hospitalization were protective factors against EUGR (P<0.05), while small-for-gestational-age birth, prolonged time to the initiation of total enteral feeding, prolonged cumulative fasting time, lower breast milk intake before starting human milk fortifiers, prolonged time to the initiation of full fortified feeding, and moderate-to-severe bronchopulmonary dysplasia were risk factors for EUGR (P<0.05). CONCLUSIONS It is crucial to reduce the incidence of EUGR by achieving total enteral feeding as early as possible, strengthening breastfeeding, increasing calorie intake in the first week after birth, improving the velocity of weight gain, and preventing moderate-severe bronchopulmonary dysplasia in VPIs.
Female ; Fetal Growth Retardation ; Gestational Age ; Hospitalization ; Humans ; Incidence ; Infant ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Prospective Studies ; Risk Factors

Objective:To evaluate the clinical application value of MR amide proton transfer weighted imaging (APTWI) in predicting the pathological grade of brainstem glioma (BSG).Methods:The data of 41 BSG patients in Beijing Tiantan Hospital, Capital Medical University from August 2019 to June 2020 who underwent both MRI and APTWI 2 weeks before surgery and had pathological grading results were retrospectively analyzed. According to the pathological results, 41 patients were classified into high-grade BSG (20 patients) and low-grade BSG (21 patients). Combined with conventional MR images, the signal intensity (%) of amide proton transfer (APT) in the parenchymal area of the tumor was obtained on APTWI images. χ 2 test or independent sample t-test was used to analyze the differences in gender distribution, age and APT signal intensity between patients with high and low grade BSG. Receiver operating characteristic (ROC) curve was drawn to predict the efficacy of APT signal intensity in the differential diagnosis of high and low grade BSG, and Youden index was calculated to obtain the optimal diagnostic threshold; the predictive ability of APT signal intensity was analyzed in combination with Hosmer-Lemeshow goodness of fit test. Results:There was no significant difference in age [(23±18) years, (20±17) years, t=0.97, P=0.340] and gender distribution (9/11, 9/12 for males/females, χ 2=0.02, P=0.890) between high-grade and low-grade BSG patients. The APT signal intensity of high-grade BSG [(3.9±0.9)%] was significantly higher than that of low-grade BSG [(2.8±0.9)%], and the difference had statistical significance ( t=4.16, P<0.001). The area under the ROC curve of APT signal intensity to distinguish high-grade and low grade BSG was 0.836, and with 2.85% as the optimal diagnostic threshold of APT signal intensity, its sensitivity for the diagnosis of high-grade BSG was 90.0% and specificity was 71.4%. The Hosmer-Lemeshow test showed that APTWI had a good predictive ability for BSG grade (χ 2=13.33, P=0.101). Conclusion:APTWI can be applied in distinguishing high grade BSG from low grade BSG, and has clinical value in predicting glioma grading.

Objective: To observe the platinum drugs resistance effect of N-acetyltransferase 10 (NAT10) overexpression in breast cancer cell line and elucidate the underlining mechanisms. Methods: The experiment was divided into wild-type (MCF-7 wild-type cells without any treatment) group, NAT10 overexpression group (H-NAT10 plasmid transfected into MCF-7 cells) and NAT10 knockdown group (SH-NAT10 plasmid transfected into MCF-7 cells). The invasion was detected by Transwell array, the interaction between NAT10 and PARP1 was detected by co-immunoprecipitation. The impact of NAT10 overexpression or knockdown on the acetylation level of PARP1 and its half-life was also determined. Immunostaining and IP array were used to detect the recruitment of DNA damage repair protein by acetylated PARP1. Flow cytometry was used to detect the cell apoptosis. Results: Transwell invasion assay showed that the number of cell invasion was 483.00±46.90 in the NAT10 overexpression group, 469.00±40.50 in the NAT10 knockdown group, and 445.00±35.50 in the MCF-7 wild-type cells, and the differences were not statistically significant (P>0.05). In the presence of 10 μmol/L oxaliplatin, the number of cell invasion was 502.00±45.60 in the NAT10 overexpression group and 105.00±20.50 in the NAT10 knockdown group, both statistically significant (P<0.05) compared with 219.00±31.50 in wild-type cells. In the presence of 10 μmol/L oxaliplatin, NAT10 overexpression enhanced the binding of PARP1 to NAT10 compared with wild-type cells, whereas the use of the NAT10 inhibitor Remodelin inhibited the mutual binding of the two. Overexpression of NAT10 induced PARP1 acetylation followed by increased PARP1 binding to XRCC1, and knockdown of NAT10 expression reduced PARP1 binding to XRCC1. Overexpression of NAT10 enhanced PARP1 binding to LIG3, while knockdown of NAT10 expression decreased PARP1 binding to LIG3. In 10 μmol/L oxaliplatin-treated cells, the γH2AX expression level was 0.38±0.02 in NAT10 overexpressing cells and 1.36±0.15 in NAT10 knockdown cells, both statistically significant (P<0.05) compared with 1.00±0.00 in wild-type cells. In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. Conclusion: NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.
Breast Neoplasms/enzymology* ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Female ; Humans ; MCF-7 Cells ; N-Terminal Acetyltransferases/metabolism* ; Organoplatinum Compounds/pharmacology* ; Oxaliplatin/pharmacology* ; X-ray Repair Cross Complementing Protein 1

OBJECTIVE: To investigate the changes in serum levels of endothelin-1 (ET-1) and connective tissue growth factor (CTGF) in patients with atrial fibrillation (AF) and their value for predicting recurrence of AF after radiofrequency ablation (RFCA). METHODS: Sixty-six patients with paroxysmal AF (PaAF) and 72 with persistent AF (PaAF) admitted in our hospital were recruited as AF group and 80 patients with sinus rhythm as the control group, and in all the participants, serum levels of ET-1 and CTGF were measured using ELISA and Western blotting. From 6 patients with AF and 6 with sinus rhythm undergoing cardiac surgery in our hospital, tissue samples of the right atrial appendage were taken intraoperatively for observation of structural changes of the cardiomyocytes, myocardial fibrosis and expression of ET-1 and CTGF protein. In AF group, the patients receiving RFCA were followed up for 6 months following the procedure for assessment of the outcomes. RESULTS: Compared with the control patients, the patients with AF showed obvious damages of the cardiomyocyte structure and myocardial fibrosis. Serum levels of ET-1 and CTGF levels were significantly higher in PaAF and PeAF groups than in the control group, and were higher in PeAF group than in PaAF group. In the patients with AF, serum ET-1 and CTGF levels were positively correlated with left atrial diameter (LAD) (P < 0.05), and ET-1 was positively correlated with CTGF levels (P < 0.05). In patients with postoperative AF recurrence, the serum levels of ET-1 and CTGF were significantly higher than those in patients without recurrence; serum ET-1 and CTGF levels before and after the operation were positively correlated with the recurrence of PeAF, and elevated serum levels of ET- 1 and CTGF were identified by logistic regression analysis as independent risk factors for postoperative recurrence of PeAF. CONCLUSION Serum levels of ET-1 and CTGF are significantly elevated in AF patients in positive correlation with AF duration. ET-1 and CTGF levels are higher in AF patients with postoperative recurrence, and they both have predictive value for recurrence of PeAF following RFCA.
Humans ; Atrial Fibrillation ; Endothelin-1 ; Connective Tissue Growth Factor ; Chronic Disease ; Atrial Appendage ; Fibrosis