4.Molecular cloning and characterization of a novel aspartyl aminopeptidase from Trichinella spiralis
Sun, X.Y. ; Ma, K.N. ; Bai, Y. ; Liu, R.D. ; Long, S.R. ; Zhang, X. ; Jiang, P. ; Cui, J. ; Wang, Z.Q.
Tropical Biomedicine 2021;38(No.3):420-434
Trichinellosis is an important zoonotic parasitic disease worldwide and is principally caused by ingesting animal meat containing Trichinella infective larvae. Aspartyl aminopeptidase is an intracytoplasmic metalloproteinase that specifically hydrolyzes the N-terminus of polypeptides free of acidic amino acids (aspartic acid and glutamate), and plays an important role in the metabolism, growth and development of organisms. In this study, a novel T. spiralis aspartyl aminopeptidase (TsAAP) was cloned and expressed, and its biological properties and roles in worm growth and development were investigated. The results revealed that TsAAP transcription and expression in diverse T. spiralis stages were detected by RT-PCR and Western blotting, and primarily localized at cuticle, stichosome and intrauterine embryos of this nematode by immunofluorescence test. rTsAAP has the enzymatic activity of native AAP to hydrolyze the substrate H-Glu-pNA. There was a specific binding between rTsAAP and murine erythrocyte, and the binding site was localized in erythrocyte membrane proteins. Silencing of TsAAP gene by specific dsRNA significantly reduced the TsAAP expression, enzymatic activity, intestinal worm burdens and female fecundity. The results demonstrated that TsAAP participates in the growth, development and fecundity of T. spiralis and it might be a potential target molecule for anti-Trichinella vaccines.
5.Content Determination of Pulegone in Schizonepeta tenuifolia and Its Compound Preparation by Hollow Fiber Liquid-phase Microextraction Coupled with HPLC
Ping LI ; Shuang HU ; Xiaohong BAI ; Xiaoping BI
China Pharmacy 2021;32(12):1427-1434
OBJECTIVE:To establish t he metho d for the content determination of pulegone in Schizonepetae tenuifolia decoction pieces and its compound preparation. METHODS :Hollow fiber liquid-phase microextraction coupled with HPLC (HF-LPME-HPLC) was adopted. Based on single factor tests ,HF-LPME condition of S. tenuifolia decoction pieces and its compound preparation (taking Compound S. tenuifolia granule as an expample ) was optimized by central composite design-response surface methodology using pulegone enrichment multiple as index ,with the concentration of sample phase solution (NaCl),extraction time and stirring speed as factors. Validation test was conducted. HPLC method was adopted to determine the content of pulegone. The determination was performed on Hypersil C 18 column with mobile phase consisted of methanol- 0.3% phosphoric acid (gradient elution )at the flow rate of 1.0 mL/min. The detection wavelength was set at 252 nm,the column temperature was 25 ℃. The sample size was 20 μL. The feasibility of HF-LPME-HPLC method established in this study was validated by using HPLC method stated in the item of S. tenuifolia decoction pieces in 2020 edition of Chinese Pharmacopoeia (part Ⅰ)as reference. RESULTS :The optimum HF-LPME conditions included n-nonanol as the extraction solvent ,sample phase solution with 11% NaCl and pH value of 7,stirring speed of 800 r/min,extraction time of 36 min. Results of HPLC methodology investigation showed that linear range of pulegone were 0.05-5 μg/mL(r=0.999 0). The limits of detection and quantitation were 0.4 and 1.3 ng/mL,respectively. RSDs of intra-day and inter-day precision were 1.8%-4.0% and 1.5%-4.1%(n=3),respectively. RSDs of reproducibility and stability tests (24 h)were all lower than 8%(n=6). Average recoveries of S. tenuifolia decoction pieces and Compound S. tenuifolia granule were 102.6%-105.1% and 97.2%-102.3%,respectively;RSDs were not higher than 4.1% and 6.2%(n=3). The average contents of pulegone in S. tenuifolia decoction pieces determined by pharmacopoeia method and established method were 0.84 mg/g(RSD=4.3% ,n=3)and 0.87 mg/g(RSD=5.5% ,n=3),respectively,with no significant difference (P>0.05). CONCLUSIONS :The established HF-LPME-HPLC method can enrich and concentrate pulegone , shows strong purification ability and high sensitivity ,and can be used to determine the contents of pulegone in S. tenuifolia decoction pieces and its compound preparation.
6.Dual roles of p62/SQSTM1 in the injury and recovery phases of acetaminophen-induced liver injury in mice.
Hui QIAN ; Qingyun BAI ; Xiao YANG ; Jephte Y AKAKPO ; Lili JI ; Li YANG ; Thomas RÜLICKE ; Kurt ZATLOUKAL ; Hartmut JAESCHKE ; Hong-Min NI ; Wen-Xing DING
Acta Pharmaceutica Sinica B 2021;11(12):3791-3805
Acetaminophen (APAP) overdose can induce liver injury and is the most frequent cause of acute liver failure in the United States. We investigated the role of p62/SQSTM1 (referred to as p62) in APAP-induced liver injury (AILI) in mice. We found that the hepatic protein levels of p62 dramatically increased at 24 h after APAP treatment, which was inversely correlated with the hepatic levels of APAP-adducts. APAP also activated mTOR at 24 h, which is associated with increased cell proliferation. In contrast, p62 knockout (KO) mice showed increased hepatic levels of APAP-adducts detected by a specific antibody using Western blot analysis but decreased mTOR activation and cell proliferation with aggravated liver injury at 24 h after APAP treatment. Surprisingly, p62 KO mice recovered from AILI whereas the wild-type mice still sustained liver injury at 48 h. We found increased number of infiltrated macrophages in p62 KO mice that were accompanied with decreased hepatic von Willebrand factor (VWF) and platelet aggregation, which are associated with increased cell proliferation and improved liver injury at 48 h after APAP treatment. Our data indicate that p62 inhibits the late injury phase of AILI by increasing autophagic selective removal of APAP-adducts and mitochondria but impairs the recovery phase of AILI likely by enhancing hepatic blood coagulation.
7.Expression and characterization of anticoagulant activity of salivary protein alALP from Asian tiger mosquito Aedes albopictus
Li, X.P. ; Lin, D. ; Zhang, Y. ; Chen, S.Q. ; Bai, H.Q. ; Zhang, S.N. ; Liu, W.Q. ; Liang, S.H.
Tropical Biomedicine 2020;37(No.1):116-126
Several bioactive molecules isolated from the saliva of blood-sucking arthropods, such as mosquitoes, have been shown to exhibit potential anticoagulant function. We have previously identified a 30kDa allergen named Aegyptin-like protein (alALP), which is highly homologous to Aegyptin, from the salivary glands of female Aedes albopictus (Asian tiger mosquito). In this study, we identified the conserved functional domain of alALP by using bioinformatic tools, and expressed the His-tagged alALP recombinant protein in sf9 insect cells by generation and transfection of a baculoviral expression plasmid carrying the fulllength cDNA of alALP. We purified this recombinant protein and examined its function on the inhibition of blood coagulation. The results showed that the purified His-alALP prolonged the Activated Partial Thromboplastin Time (APTT), Prothrombin Time (PT) and Thrombin Time (TT) in vitro as well as the Bleeding Time (BT) in vivo, which suggest that alALP could be a novel anticoagulant.
8.Impact of taxanes on androgen receptor signaling.
Shanshan BAI ; Bryan Y ZHANG ; Yan DONG
Asian Journal of Andrology 2019;21(3):249-252
The development and progression of metastatic castration-resistant prostate cancer is the major challenge in the treatment of advanced prostate cancer. The androgen receptor signaling pathway remains active in metastatic castration-resistant prostate cancer. Docetaxel and cabazitaxel are the first- and second-line chemotherapy, respectively, for patients with metastatic castration-resistant prostate cancer. These two taxanes, in general, function by (i) inhibiting mitosis and inducing apoptosis and (ii) preventing microtubule-dependent cargo trafficking. In prostate cancer, taxanes have been reported to inhibit the nuclear translocation and activity of the androgen receptor. However, whether this is attainable or not clinically remains controversial. In this review, we will provide a comprehensive view of the effects of taxanes on androgen receptor signaling in prostate cancer.
Antineoplastic Agents, Phytogenic/therapeutic use*
;
Humans
;
Male
;
Prostatic Neoplasms, Castration-Resistant/drug therapy*
;
Receptors, Androgen/drug effects*
;
Signal Transduction/drug effects*
;
Taxoids/therapeutic use*
9.Sentinel surveillance for viral hepatitis C in China, 2016-2017.
G W DING ; S D YE ; F X HEI ; Q L LIAN ; X D PEI ; J Y BAI ; D ZHOU ; Q YANG ; S HUI ; W WANG ; A X TU ; L PANG
Chinese Journal of Epidemiology 2019;40(1):41-45
Objective: To understand the prevalence of hepatitis C virus (HCV) infection in 5 populations in China during 2016-2017 and provide evidence for the estimation of prevalence trend of hepatitis C and evaluation on the prevention and control effect. Methods: A total of 87 national sentinel surveillance sites for hepatitis C were set up in 31 provinces (autonomous regions and municipalities) of China to obtain the information about HCV infection prevalence in 5 populations, including volunteer blood donors, people receiving physical examination, patients receiving invasive diagnosis and treatment, patients receiving hemodialysis, and clients visiting family planning outpatient clinics. From April to June, 2016 and 2017, cross-sectional surveys were repeatedly conducted in the 5 populations and blood samples were collected from them for HCV antibody detection. Results: In 2016, 86 sentinel sites completed the surveillance (one sentinel site was not investigated), and 115 841 persons were surveyed. The overall HCV positive rate was 0.38% (442/115 841, 95%CI: 0.23%-0.53%). In 2017, all the 87 sentinel sites completed the surveillance, and 120 486 persons were surveyed. The overall HCV positive rate was 0.37% (449/120 486, 95%CI: 0.23%-0.52%). In 2016 and 2017, the anti-HCV positive rates were 4.46% (223/5 005, 95%CI: 2.18%-6.73%) and 4.39% (216/4 919, 95%CI: 2.29%-6.50%) respectively in hemodialysis patients, 0.85% (44/5 200, 95%CI: 0.27%-1.42%) and 0.70% (36/5 150, 95%CI: 0.15%-1.24%) respectively in patients receiving invasive diagnosis and treatment and remained to be ≤0.25% in volunteer blood donors, people receiving physical examination and clients visiting family planning outpatient clinics. Results for the comparison of the anti-HCV positive rates in the 5 populations indicated that the differences were significant (F=23.091, P<0.001 in 2016 and F=20.181, P<0.001 in 2017). Conclusions: Data from the sentinel surveillance of HCV infection on prevalence in China showed that the anti-HCV positive rates varied in the 5 populations during 2016-2017. The anti-HCV positive rate appeared the highest in the hemodialysis patients, followed by that in the patients receiving invasive diagnosis and treatment, and the prevalence of HCV infection in other 3 populations were at low levels.
China/epidemiology*
;
Cross-Sectional Studies
;
Hepacivirus
;
Hepatitis C/epidemiology*
;
Hepatitis C Antibodies
;
Humans
;
Prevalence
;
Sentinel Surveillance
10.Bibliometrics and visualization analysis of land use regression models in ambient air pollution research.
Y J ZHANG ; D H ZHOU ; Z P BAI ; F X XUE
Chinese Journal of Epidemiology 2018;39(2):227-232
Objective: To quantitatively analyze the current status and development trends regarding the land use regression (LUR) models on ambient air pollution studies. Methods: Relevant literature from the PubMed database before June 30, 2017 was analyzed, using the Bibliographic Items Co-occurrence Matrix Builder (BICOMB 2.0). Keywords co-occurrence networks, cluster mapping and timeline mapping were generated, using the CiteSpace 5.1.R5 software. Relevant literature identified in three Chinese databases was also reviewed. Results: Four hundred sixty four relevant papers were retrieved from the PubMed database. The number of papers published showed an annual increase, in line with the growing trend of the index. Most papers were published in the journal of Environmental Health Perspectives. Results from the Co-word cluster analysis identified five clusters: cluster#0 consisted of birth cohort studies related to the health effects of prenatal exposure to air pollution; cluster#1 referred to land use regression modeling and exposure assessment; cluster#2 was related to the epidemiology on traffic exposure; cluster#3 dealt with the exposure to ultrafine particles and related health effects; cluster#4 described the exposure to black carbon and related health effects. Data from Timeline mapping indicated that cluster#0 and#1 were the main research areas while cluster#3 and#4 were the up-coming hot areas of research. Ninety four relevant papers were retrieved from the Chinese databases with most of them related to studies on modeling. Conclusion: In order to better assess the health-related risks of ambient air pollution, and to best inform preventative public health intervention policies, application of LUR models to environmental epidemiology studies in China should be encouraged.
Air Pollutants/analysis*
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Air Pollution
;
Bibliometrics
;
China
;
Environment
;
Environmental Monitoring/methods*
;
Humans
;
Models, Theoretical
;
Periodicals as Topic
;
Regression Analysis
;
Research


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