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Huang L, Chen Z, Song Y, Tan J, Jia N, You W, Yuan H, Feng G, Li C, Luan C, Quan Y, Wang Y. Immunogenicity and safety of a live-attenuated varicella vaccine in a healthy population aged 13 years and older: A randomized, double-blind, controlled study. Vaccine 2024; 42:396-401. [PMID: 38057208 DOI: 10.1016/j.vaccine.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/27/2023] [Accepted: 10/13/2023] [Indexed: 12/08/2023]
Abstract
OBJECTIVES Vaccines for prevention against varicella are important for adolescents and adults, who have an increased risk of severe varicella. This study aimed to evaluate the immunogenicity and safety of a two-dose immunization schedule of a live-attenuated varicella vaccine (VarV) manufactured by Sinovac (Dalian) in healthy adolescents and adults. METHODS A randomized, double-blind, controlled clinical trial was conducted in healthy population aged ≥ 13 years old in China. Participants in block 1 were randomly assigned (1:1) to receive two doses of either the test vaccine or an active control vaccine, administered 4, 6 or 8 weeks apart. Participants in block 2 were randomly assigned (2:1) to receive two doses of test vaccine or placebo, administered 10 weeks apart. The primary immunogenicity endpoint was the seroconversion rates and GMTs of varicella zoster virus (VZV) antibodies measured by fluorescent-antibody-to-membrane-antigen (FAMA) 4 weeks post-immunization. The primary safety endpoint was the incidence of adverse reactions within 4 weeks after each dose. RESULTS A total of 2398 participants were enrolled. The seroconversion rates of VZV antibodies were 79.55 % in the test group and 76.41 % in the active control group respectively 4 weeks after two doses of pooled schedule, with the difference of 3.14 % (95 %CI: -0.69 %, 6.97 %). The GMTs were 1:162.07 and 1:160.04 respectively, with the ratio of 1.013 (95 %CI: 0.910, 1.127). Both the seroconversion rates and GMTs reached the prespecified non-inferiority criteria. Two-dose schedule with an interval of 10 weeks could also induce high immune responses, with a seroconversion rate of 83.22 % and a GMT of 1:160.38 in the test group. Safety profiles were similar among the test group, active control group and placebo group. CONCLUSION VarV, manufactured by Sinovac (Dalian), demonstrated higher immune response and better flexibility in the immunization schedule among heathy population aged 13 years and older, without increased safety risk.
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Affiliation(s)
- Lili Huang
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, China
| | - Zhen Chen
- National Institutes for Food and Drug Control, Beijing, China
| | - Yufei Song
- Sinovac Biotech Co., Ltd., Beijing, China
| | - Jiebing Tan
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, China
| | | | - Wangyang You
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, China
| | - Hongxue Yuan
- Sinovac (Dalian) Vaccine Technology Co., Ltd., Dalian, China
| | - Guangwei Feng
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, China
| | - Changgui Li
- National Institutes for Food and Drug Control, Beijing, China
| | - Chunfang Luan
- Sinovac (Dalian) Vaccine Technology Co., Ltd., Dalian, China.
| | - Yaru Quan
- National Institutes for Food and Drug Control, Beijing, China.
| | - Yanxia Wang
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, Henan, China.
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Sun D, Yu D, Du Z, Jia N, Liu X, Sun J, Xu Q, Sun Z, Luan C, Lv J, Xiong P, Zhang L, Sha X, Gao Y, Kang D. Immunogenicity and safety of a live attenuated varicella vaccine co-administered with inactive hepatitis A vaccine: A phase 4, single-center, randomized, controlled trial. Hum Vaccin Immunother 2023; 19:2161789. [PMID: 36593652 PMCID: PMC9936993 DOI: 10.1080/21645515.2022.2161789] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Co-administration of vaccines can facilitate the introduction of new vaccines in immunization schedules. This study aimed to evaluate the immunogenicity and safety of co-administration with live attenuated varicella vaccine (VarV) and inactivated hepatitis A vaccine (HepA) among children aged 12 ~ 15 months. In this phase 4 clinical trial, 450 children were randomized with a ratio of 1:1 to receive VarV and Hep A simultaneously (Group A) or separately (Group B). The primary endpoints were the seroconversion rate of anti-varicella-zoster virus (VZV) antibodies 42 days after vaccination of VarV and the seroconversion rate of anti-Hepatitis A virus (HAV) antibodies 30 days after two-dose vaccination of HepA. After full immunization, the seroconversion rates of anti-VZV antibodies were 91.79% in Group A and 92.15% in Group B; the geometric mean titers (GMTs) were 11.80 and 12.19, respectively. The seroconversion rates of anti-HAV antibodies were 99.48% in Group A and 100.0% in Group B; the geometric mean concentrations (GMCs) reached 9499.11 and 9528.36 mIU/ml, respectively. The lower limits of the 95% CI for the seroconversion difference of anti-VZV antibodies and anti-HAV antibodies were -5.86% and -2.90%, which greater than the predefined non-inferiority margin (-10%). The incidence rate of adverse reactions in Group A was lower than Group B (9.33% vs 16.22%), and only one serious adverse event was reported in Group B, which was unrelated to the study vaccine. In conclusion, the co-administration of VarV with HepA has non-inferior immunogenicity and safety profiles were quite comparable with the separate administration of both vaccines.Trial registration number: NCT05526820 (ClinicalTrials.gov).
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Affiliation(s)
- Dapeng Sun
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China
| | - Dan Yu
- Medical Affairs Department, Sinovac Biotech Co., Ltd, Beijing, China
| | - Zhenhua Du
- Department Of Immunology, FeiCheng Center for Disease Control and Prevention, Taian, China
| | - Ningning Jia
- Medical Affairs Department, Sinovac Biotech Co., Ltd, Beijing, China
| | - Xiaodong Liu
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China
| | - Jianwen Sun
- Medical Affairs Department, Sinovac Life Science Co, Ltd, Beijing, China
| | - Qing Xu
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China
| | - Zhuoqun Sun
- Medical Affairs Department, Sinovac Life Science Co, Ltd, Beijing, China
| | - Chunfang Luan
- Research and Development Department, Sinovac (Dalian) Vaccine Technology Co., Ltd, Dalian, China
| | - Jingjing Lv
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China
| | - Ping Xiong
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China
| | - Li Zhang
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China,School of Public Health, Shandong University, Jinan, China
| | - Xueyan Sha
- Research and Development Department, Sinovac (Dalian) Vaccine Technology Co., Ltd, Dalian, China
| | - Yongjun Gao
- Medical Affairs Department, Sinovac Biotech Co., Ltd, Beijing, China,CONTACT Yongjun Gao Medical Affairs Department, Sinovac Biotech Co., Ltd, No.8 Dongbeiwang West Road, Haidian District, Beijing, China
| | - Dianmin Kang
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Center for Disease Control and Prevention, Jinan, China,School of Public Health, Shandong University, Jinan, China
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Hu W, Jia N, Meng W, Zhou T, Wang R, Xiong Y, Luan C, Zhang S. Safety analysis of a live attenuated mumps vaccine in healthy adolescents in China: A phase 4, observational, open-label trial. PLoS One 2023; 18:e0291730. [PMID: 37733724 PMCID: PMC10513284 DOI: 10.1371/journal.pone.0291730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/01/2023] [Indexed: 09/23/2023] Open
Abstract
Mumps is an acute infectious disease, which was well controlled in the past, but recently it has resurged in some areas. This study aimed to evaluate the safety profile of the live attenuated mumps vaccine after large-scale vaccination. We conducted an observational, open-label phase 4 trial in Shaanxi, China from October 2020 to March 2021. Eligible participants were freshmen of junior high school who were not above 14 years old. Adverse events following immunization (AEFI) monitoring was carried out by active and passive surveillance. Safety follow-ups were conducted during the study participation. Overall, 10057 subjects were enrolled in the active surveillance analysis. A total of 214 subjects reported adverse reactions with an incidence of 2.13% (214/10057). Most adverse reactions were grade 1, and the incidence of grade 1 adverse reactions was 1.44% (145/10057); 0.60% for grade 2 (60/10057); and 0.09% for grade 3 (9/10057). The majority of adverse reactions were solicited (1.73%, 174/10057). Injection-site pain was the most frequently reported local adverse reaction (0.71%, 71/10057), followed by redness (0.29%, 29/10057). The most common systemic adverse reactions were nausea (0.19%, 19/10057) and fever (0.16%, 16/10057). For passive AEFI surveillance, 57 AEFI cases were reported, with an incidence of 19.28/100000 (57/287608). And most AEFI cases were common adverse reactions (66.67%, 38/57). In total, the live attenuated mumps vaccine evaluated in this trial has a favorable safety profile and can be used for large-scale inoculation.
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Affiliation(s)
- Weijun Hu
- Immunization Programme Institute, Vaccine Clinical Evaluation Center, Shaanxi Provincial Center for Disease Control and Prevention, Xi’an, China
| | - Ningning Jia
- Clinical Research and Development Center, Sinovac Biotech Co., LTD, Beijing, China
| | | | - Tiantian Zhou
- Immunization Programme Institute, Vaccine Clinical Evaluation Center, Shaanxi Provincial Center for Disease Control and Prevention, Xi’an, China
| | - Ruize Wang
- Immunization Programme Institute, Vaccine Clinical Evaluation Center, Shaanxi Provincial Center for Disease Control and Prevention, Xi’an, China
| | | | - Chunfang Luan
- Research and Development Center, Sinovac (Dalian) Vaccine Technology Co., LTD, Dalian, China
| | - Shaobai Zhang
- Immunization Programme Institute, Vaccine Clinical Evaluation Center, Shaanxi Provincial Center for Disease Control and Prevention, Xi’an, China
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Zhao Z, Liu X, Luan C, Liu X, Wang D, Qin T, Sui L, Zhang W. Architecting hierarchical shell porosity of hollow prussian blue-derived iron oxide for enhanced Li storage. J Microsc 2019; 276:53-62. [PMID: 31603242 DOI: 10.1111/jmi.12836] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 09/12/2019] [Accepted: 10/01/2019] [Indexed: 11/28/2022]
Abstract
Delicate architecture of active material enables improving the performacne of lithium ion batteries. Environmental-friendly Fe2 O3 anode has high theoretical specific capacity (1007 mAh g-1 ) in lithium ion batteries, but suffers from structural collapsing and poor electronic conductivity. Herein, we design an unique hierarchical iron oxide by regulating the initial precursor prussian blue and targeting hollow-shell structures with full consideration of temperature controls. Among them, Fe2 O3 with a sheet-crossing structure at 650°C, affords obvious advantages of improved electronic conductivity, short ionic diffusion length, prevented particle agglomeration, and buffer volume change. Thus, we achieve a superior discharge specific capacity of 611 mAh g-1 at 500 mA g-1 . Regulating hierarchical structure of prussian blue-assisted oxides enables effectively enchancing Li storge performance. LAY DESCRIPTION: Nanoparticle self-assembly, one of bottom-up methods is often used to prepare hollow hierarchical structures, whereas it suffers from low productivity and insufficient stability. Hence, we designed a unique hierarchical iron oxide by top-down method with regulating the initial precursor PB and targeting hollow-shell structures through full consideration of temperature controls. Delicate architecture of active material enables improving the performacne of lithium ion batteries. Environmental-friendly Fe2 O3 anode has high theoretical specific capacity (1007 mAh g-1 ) in lithium ion batteries, but suffers from structural collapsing and poor electronic conductivity. Hence, we prepared Prussian Blue (PB) materials with different sizes and calcined them at different temperatures. We found that no matter what the size of PB, the sheet-crossing morphology appeared at 650°C, and the interlaced morphology was the key to improve the performance of lithium batteries. If the size of PB precursor is too large or too small, it has adverse effects on lithium batteries. Only when the size and calcination temperature of PB precursor reach the optimum state, the best performance can be obtained. The calcination PB-K-3 at 650°C has a unique hierarchical structure of sheet-crossing. An obvious advantages include the prevention of particle agglomeration, short ionic diffusion lengths, and buffering volume changes. As a consequence, 611 mAh g-1 was obtained at the current density of 500 mA g-1 . In addition, we observed the structural changes of electrode plates at different reaction potentials, according to the reaction equation of Fe2 O3 +xLi+ +xe→Lix Fe2 O3 . With the proceeding charge process, the voltage increases from 0.01 to 3 V, the lithium ions gradually comes out of the iron oxide electrode surface. Whereas the discharging process reverses the aforementioned phenomena. Even if the changing volumes, however, the shape of cubic blocks for the PB-K-3 is preserved at different potentials. Taking these advantages into account, our designed MOFs-derived struture was an effective way to prepare hollow hierarchical structure with enhanced Li storage performacne. Such work is expected to facilitate the design of new electrode structure of lithium batteries.
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Affiliation(s)
- Z Zhao
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China
| | - X Liu
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China.,College of Biological and Agricultural Engineering, Jilin University, Changchun, China
| | - C Luan
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China
| | - X Liu
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China
| | - D Wang
- State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, Hunan University, Changsha, China
| | - T Qin
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China
| | - L Sui
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China
| | - W Zhang
- Key Laboratory of Mobile Materials MOE, School of Materials Science & Engineering, Electron Microscopy Center, International Center of Future Science, Jilin University, Changchun, China.,Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
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Hao B, Chen Z, Zeng G, Huang L, Luan C, Xie Z, Chen J, Bao M, Tian X, Xu B, Wang Y, Wu J, Xia S, Yuan L, Huang J. Efficacy, safety and immunogenicity of live attenuated varicella vaccine in healthy children in China: double-blind, randomized, placebo-controlled clinical trial. Clin Microbiol Infect 2019; 25:1026-1031. [DOI: 10.1016/j.cmi.2018.12.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 12/18/2018] [Accepted: 12/22/2018] [Indexed: 10/27/2022]
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Liu X, Yang K, Zhao S, Li T, Luan C, Guo X, Zhao B, Zheng L, Su L, Xu J, Bian J. Growth and lasing performance of a Tm,Y:CaF 2 crystal. Opt Lett 2017; 42:2567-2570. [PMID: 28957286 DOI: 10.1364/ol.42.002567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 06/05/2017] [Indexed: 06/07/2023]
Abstract
A Tm3+ ion and Y3+ ion co-doped CaF2 crystal was grown and characterized, in which spectral and lasing performance was presented for the first time, to the best of our knowledge. Under diode end-pumping, in a continuous-wave regime, maximum output power of 453 mW was delivered under an absorption pump power of 2.5 W, corresponding to an optical-to-optical conversion efficiency of 17.9% and a slope efficiency of 21%. With a birefringent quartz plate, wavelength-tunable operation with a tunable range of more than 190 nm was realized. The results show that Tm,Y:CaF2 is a promising laser crystal operating in a spectral region ranging from 1850 nm to 2050 nm.
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Luan C, Yang K, Zhao J, Zhao S, Li T, Zhang H, He J, Song L, Dekorsy T, Guina M, Zheng L. Diode-pumped mode-locked Tm:LuAG laser at 2 μm based on GaSb-SESAM. Opt Lett 2017; 42:839-842. [PMID: 28198878 DOI: 10.1364/ol.42.000839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mode-locking of a directly diode-pumped Tm:LuAG laser is demonstrated using GaSb-based semiconductor saturable absorber mirrors (SESAMs). Stable and self-starting mode-locked operation was realized, generating pulses as short as 13.6 ps at 2024 nm with a maximum output power of 98 mW. Two GaInAs-based SESAMs were used for comparison with the operation based upon the use of the GaSb SESAM; in this case, longer pulses with durations of 27 ps and 34 ps were obtained under the same experimental conditions. Our work sets a new record in pulse duration for mode-locked Tm:LuAG lasers and confirms that lattice-matched GaSb-based SESAMs are beneficial for mode-locked solid-state lasers in the 2 μm range.
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Han SL, Wan SL, Li QT, Xu DT, Zang HM, Chen NJ, Chen LY, Zhang WP, Luan C, Yang F, Xu ZW. Is vertebroplasty a risk factor for subsequent vertebral fracture, meta-analysis of published evidence? Osteoporos Int 2015; 26:113-22. [PMID: 25149856 DOI: 10.1007/s00198-014-2848-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 08/10/2014] [Indexed: 10/24/2022]
Abstract
UNLABELLED In our paper, we systemically retrieved the eligible study evaluating whether increased incidence of subsequent vertebral fracture is associated with vertebroplasty. Main effect sizes were vertebral fracture rates reported in terms of hazard ratio (HR) for time-to-event data or relative risk (RR) for dichotomous outcome. Our results do not support the hypothesis that vertebroplasty contributes to increased risk of subsequent vertebral fracture, neither adjacent nor total vertebral fracture. INTRODUCTION Vertebroplasty has been implicated in significant changes in vertebral strength, vertebral shape, and consequently increased risk for subsequent vertebral fracture, especially the adjacent level. Here, we further tested the hypothesis whether new-onset vertebral fracture is a natural result of osteoporosis or consequence of cement augmentation. METHODS Relevant literatures were retrieved using PubMed, Web of Knowledge, and Cochrane Central Register of Controlled Trials (CENTRAL), supplemented by a hand-search of the reference lists of selected articles. Eligible studies assessed whether increased morbidity of subsequent vertebral fracture is associated with vertebroplasty. Main effect sizes were vertebral fracture rates reported in terms of hazard ratio (HR) for time-to-event data or relative risk (RR) for dichotomous outcome. Random-effects model was used to account for clinical or methodological heterogeneity across studies. RESULTS Thirteen studies with a number of 2,551 individuals (1,631 in vertebroplasty group and 920 in control group) were suitable for this meta-analysis. In trials that reported adjacent vertebral fracture as time-to-event data (two trials, n = 328), we found a similar incidence of vertebral fracture in percutaneous vertebroplasty (PVP) group compared to conservative therapy (HR 0.60, 95% confidence interval 0.29 to 1.26; P = 0.18). In trials that reported overall vertebral fracture as time-to-event data (three trials, n = 704), vertebroplasty was associated with a slightly increased but non-significant risk for vertebral fracture (HR 1.14, 95% confidence interval 0.65 to 2.00; P = 0.65). The outcome was further confirmed in the secondary meta-analysis of studies that reported vertebral fracture as dichotomous data. Subgroup analysis according to study design revealed no difference either. CONCLUSIONS Our results do not support the hypothesis that vertebroplasty contributes to increased risk of subsequent vertebral fracture, neither adjacent nor total vertebral fracture. However, adequately designed randomized controlled trials are warranted to confirm the present findings.
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Affiliation(s)
- S L Han
- Department of Orthopaedics, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 East Qingchun Road, Hangzhou, Zhejiang, 310016, China
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Han FF, Gao YH, Luan C, Xie YG, Liu YF, Wang YZ. Comparing bacterial membrane interactions and antimicrobial activity of porcine lactoferricin-derived peptides. J Dairy Sci 2013; 96:3471-87. [PMID: 23567049 DOI: 10.3168/jds.2012-6104] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 02/11/2013] [Indexed: 11/19/2022]
Abstract
Antibiotic treatment for microbial infections is under scrutiny due to increasing resistance to conventional antibiotics, warranting discovery of new classes of antibiotic agents. Antimicrobial peptides are part of the innate defense system found in nearly all organisms and possess bactericidal mechanisms that make it more difficult for bacteria to develop resistance. Porcine lactoferricin (LFP-20) is an antimicrobial peptide located in the N terminus of lactoferrin (LF). To develop novel cell-selective antimicrobial peptides with improved antimicrobial specificity compared with LFP-20, analogs LF2A LF-2, LF-4, and LF-6 were substituted with Ala, Ser, or Trp residues at different positions in the molecule. Analogs displayed a 2- to 16-fold higher antimicrobial activity than LFP-20, but were hemolytic at 64 μg/mL. Additionally, LFP-20, LF2A, LF-2, and LF-4 exhibited lower cytotoxicity against human peripheral blood mononuclear cells than LF-6 at concentrations of 25 to 100 μg/mL. To better understand the antibacterial mechanisms of LFP-20 and its analogs we examined their effect on the cytoplasmic membrane of Escherichia coli. The LFP-20 was not effective in depolarizing cytoplasmic membranes, whereas the other 3 analogs gradually dissipated the membrane potential of E. coli. Membrane potential increased with minimal inhibitory concentrations changes, demonstrating a correlation between bactericidal activity and membrane depolarization. Analogs were more efficient than LFP-20 in displacing lipopolysaccharide-bound dansyl-polymyxin B, which also rapidly increased 1-N-phenyl-naphthylamine uptake and release of cytoplasmic β-galactosidase by increasing the permeability of the outer and inner membranes of E. coli. The 3 analogs caused an increased potential for calcein leakage from negatively charged lipid vesicles at high concentrations. Collectively, these results suggest that the first targets of LF-2, LF-4, and LF-6 in E. coli are cytoplasmic membranes. The 3 analogs exhibited lethal effects based on their abilities to disrupt membranes and permit transit of large intracellular components, such as calcein.
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Affiliation(s)
- F F Han
- Key Laboratory of Molecular Animal Nutrition, Ministry of Agriculture and Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Institute of Feed Science, Zhejiang University, Hangzhou 310058, China
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Luan C, Li Y, Wei B. [Study on fluorimetry of aluminum quaternary complex and analytical application]. Hua Xi Yi Ke Da Xue Xue Bao 2000; 31:415-8. [PMID: 12545850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
This study was conducted to seek an easy-to-do method for determination of aluminum in biological and food samples. The fluorescent reaction of aluminum forming quaternary complex with fluoride, Ferron and CTMAB in the buffer solution of ammonium acetate (at pH 6.0) was investigated. The conditions of the reaction and the pretreatment of samples were optimized. In addition, the aluminum contents of hair and food samples was detected. A good linear relationship between fluorescence intensity and aluminum concentrations from 0.002 microgram/ml to 0.20 microgram/ml was observed. The detection limit was 1.0 x 10(-3) micrograms/ml. The spiked recoveries were in the range of 88.66%-112.61% with relative standard deviation varying from 1.87% to 2.56%. This method has characters of good sensitivity, selectivity and the ability against interference, it can be of wide application.
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Affiliation(s)
- C Luan
- Department of Sanitary Technology, School of Public Health, WCUMS, Chengdu 610041
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Wang L, Liu Z, Yang Q, Luan C. [Analysis and prevention of dislocation after total hip replacement]. Zhonghua Wai Ke Za Zhi 1999; 37:626-8. [PMID: 11829909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To analyse and prevent postoperative dislocation after total hip replacement (THR). METHODS Of 850 cases operated on by THR 15 (1.7%) had postoperative dislocation. Eleven were revision cases while the other 4 were operated on their primary procedures. RESULTS Postoperative dislocation after THR were found in 15 cases. Eleven cases had posterior dislocation by posterolateral approach after revision of THR. Anterior dislocation occurred in 2 cases who received lateral approach. Another two cases of dislocation were related to the design of prosthesis. Separation of polyethylene liner and metal shell in acetabular prosthesis was noted in the two cases. All the cases but 1 were reduced operatively. The cases with malpositioned prosthesis were revised operatively. Augmentation procedure was carried out to increase the strength of abductor. In one case, relocation of the great trochantor increased the strength of abductor. No redislocation was observed during follow-up. CONCLUSIONS Postoperative dislocation after THR are due to malpositioning of prosthesis, unbalanced bilateral soft tissues, especially the loosening of abductor. Evaluating carefully the development of the pelvis and the deviation of normal bone markers is important in addition to accurate insertion and installment of the prosthesis intraoperatively. Complete clearance of osteophytes and bone cements around the acetabulumis reqaired apart from the repairment of adjacent soft tissues. Double check of hip stability should be carried out before the closure of incision.
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Affiliation(s)
- L Wang
- Department of Orthopaedics, Ruijin Hospital, Shanghai Second Medical University. Shanghai Institute of Traumatology and Orthopaedics, Shanghai 200025
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Liu Y, Fu X, Han H, Cheng B, Luan C. Spectral structure for a class of one-dimensional three-tile quasilattices. Phys Rev B Condens Matter 1991; 43:13240-13245. [PMID: 9997149 DOI: 10.1103/physrevb.43.13240] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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