BF-30 effectively inhibits ciprofloxacin-resistant bacteria in vitro and in a rat model of vaginosis

Wang, Jing,Li, Bing,Li, Yang,Dou, Jie,Hao, Qingru,Tian, Yuwei,Wang, Hui,Zhou, Changlin 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7

Bacterial infections are becoming increasingly difficult to treat due to the increasing number of multidrug-resistant strains. Cathelicidin-BF (BF-30) is a cathelicidin-like antimicrobial peptide and exhibits broad antimicrobial activity against bacteria. In the present study, the antibacterial activity of BF-30 against ciprofloxacin-resistant Escherichia coli and Staphylococcus aureus was examined, and the protective effects of this peptide against these bacteria in rats with bacterial vaginosis were identified for the first time. The data showed that BF-30 had effective antimicrobial activities against ciprofloxacin-resistant E. coli and S. aureus. The minimal inhibitory concentrations for both bacterial strains were $16{\mu}g/ml$, and the minimal bactericidal concentrations were 64 and $128{\mu}g/ml$, respectively. A time course experiment showed that the CFU counts rapidly decreased after BF-30 treatment, and the bacteria were nearly eliminated within 4 h. BF-30 could reduce the fold change (CFU/ml) in local colonization by drug-resistant E. coli and S. aureus to 0.01 at a dose of 0.8 mg/kg/day in the rats' vaginal secretions. In addition, BF-30 induced membrane permeabilization and bound to the genomic DNA, interrupting protein synthesis. Taken together, our data demonstrate that BF-30 has potential therapeutic value for the prevention and treatment of bacterial vaginosis.

BF-30 effectively inhibits ciprofloxacin-resistant bacteria in vitro and in a rat model of vaginosis

Jing Wang,Bing Li,Yang Li,Jie Dou,Qingru Hao,Yuwei Tian,Hui Wang,Changlin Zhou 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7

Bacterial infections are becoming increasinglydifficult to treat due to the increasing number of multidrugresistantstrains. Cathelicidin-BF (BF-30) is a cathelicidinlikeantimicrobial peptide and exhibits broad antimicrobialactivity against bacteria. In the present study, the antibacterialactivity of BF-30 against ciprofloxacin-resistantEscherichia coli and Staphylococcus aureus was examined,and the protective effects of this peptide against these bacteriain rats with bacterial vaginosis were identified for thefirst time. The data showed that BF-30 had effective antimicrobialactivities against ciprofloxacin-resistant E. coliand S. aureus. The minimal inhibitory concentrations forboth bacterial strains were 16 lg/ml, and the minimal bactericidalconcentrations were 64 and 128 lg/ml, respectively. A time course experiment showed that the CFUcounts rapidly decreased after BF-30 treatment, and thebacteria were nearly eliminated within 4 h. BF-30 couldreduce the fold change (CFU/ml) in local colonization bydrug-resistant E. coli and S. aureus to 0.01 at a dose of0.8 mg/kg/day in the rats’ vaginal secretions. In addition,BF-30 induced membrane permeabilization and bound to thegenomic DNA, interrupting protein synthesis. Taken together,our data demonstrate that BF-30 has potential therapeuticvalue for the prevention and treatment of bacterialvaginosis.

Potent antibacterial and antibiofilm activities of TICbf-14, a peptide with increased stability against trypsin

Wang Liping,Liu Xiaoyun,Ye Xinyue,Zhou Chenyu,Zhao Wenxuan,Zhou Changlin,Ma Lingman 한국미생물학회 2022 The journal of microbiology Vol.60 No.1

The poor stability of peptides against trypsin largely limits their development as potential antibacterial agents. Here, to obtain a peptide with increased trypsin stability and potent antibacterial activity, TICbf-14 derived from the cationic peptide Cbf-14 was designed by the addition of disulfide-bridged hendecapeptide (CWTKSIPPKPC) loop. Subsequently, the trypsin stability and antimicrobial and antibiofilm activities of this peptide were evaluated. The possible mechanisms underlying its mode of action were also clarified. The results showed that TICbf-14 exhibited elevated trypsin inhibitory activity and effectively mitigated lung histopathological damage in bacteria-infected mice by reducing the bacterial counts, further inhibiting the systemic dissemination of bacteria and host inflammation. Additionally, TICbf-14 significantly repressed bacterial swimming motility and notably inhibited biofilm formation. Considering the mode of action, we observed that TICbf-14 exhibited a potent membrane-disruptive mechanism, which was attributable to its destructive effect on ionic bridges between divalent cations and LPS of the bacterial membrane. Overall, TICbf-14, a bifunctional peptide with both antimicrobial and trypsin inhibitory activity, is highly likely to become an ideal candidate for drug development against bacteria.

A Study on Construction and Simulation of Agricultural Machinery System Control Model

Wang Ying,Xu Shiyang,Liu Shiqiang,Li Xiaoxue,Ao Changlin 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.8

In order to study the state-changing and running rules of agricultural machinery system, this paper establishes the control model of agricultural machinery system under the discrete-state space based on control theory, from the perspective of the complex systems and with reference to the actual conditions of agricultural production; conducts the qualitative analysis on the system model, builds the relevant simulation model of agricultural machinery system accordingly, and verifies the running of the simulation model. This control model can provide effective basis and reference for further quantitative studies on state evolution of agricultural machinery system.

Non-parameter Estimation of Failures Intensity of Tractor Based on Bootstrap

Yanfang Wang,Changlin Ao 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.1

Particle swarm optimization of fuzzy PI control for PMSMs

Shijiao Wang,Chengming Jiang,Qunzhang Tu,Huidong Shu,Changlin Zhu 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.10

To solve the problems of the slow response speed and poor adaptive capability of a permanent magnet synchronous motor (PMSM) under a fuzzy PI control system, a particle swarm optimization (PSO) fuzzy PI method is proposed as a parameter optimization control scheme in this paper. The proportion factor and quantization factor in fuzzy PI control are optimized through the iteration of a PSO algorithm. In addition, the parameters of the PI control are intelligently adjusted through thefuzzy control. A simulation model is developed using MATLAB/Simulink, and an experimental platform is constructed to verify the proposed algorithm. Test results demonstrate that the fuzzy PI control optimized by PSO improves the convergence accuracy of a system and reduces the speed ring overshoot to a minimum. Furthermore, the PSO-optimized fuzzy PI control exhibits characteristics such as small torque ripple, strong anti-interference capability, and fast dynamic response.

A Three-way Handshaking Access Mechanism for Point to Multipoint In-band Full-duplex Wireless Networks

( Haiwei Zuo ),( Yanjing Sun ),( Changlin Lin ),( Song Li ),( Hongli Xu ),( Zefu Tan ),( Yanfen Wang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.7

In-band Full-duplex (IBFD) wireless communication allows improved throughput for wireless networks. The current Half-duplex (HD) medium access mechanism Request to Send/Clear to Send (RTS/CTS) has been directly applied to IBFD wireless networks. However, this is only able to support a symmetric dual link, and does not provide the full advantages of IBFD. To increase network throughput in a superior way to the HD mechanism, a novel three-way handshaking access mechanism RTS/SRTS (Second Request to Send)/CTS is proposed for point to multipoint (PMP) IBFD wireless networks, which can support both symmetric dual link and asymmetric dual link communication. In this approach, IBFD wireless communication only requires one channel access for two-way simultaneous packet transmissions. We first describe the RTS/SRTS/CTS mechanism and the symmetric/asymmetric dual link transmission procedure and then provide a theoretical analysis of network throughput and delay using a Markov model. Using simulations, we demonstrate that the RTS/SRTS/CTS access mechanism shows improved performance relative to that of the RTS/CTS HD access mechanism.

The antimicrobial activity of Cbf-K16 against MRSA was enhanced by β-lactamantibiotics through cell wall non-integrity

Bo Li,Wei Kang,Hanhan Liu,Yanrong Wang,Changzhong Yu,Xinyi Zhu,Jie Dou,Haibo Cai,Changlin Zhou 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as one of the most important pathogens both in health care and in community-onset infections. Cbf-K16, a cathelicidin-like antimicrobial peptide, presented broad antimicrobial activity during our previous studies. We evaluated the potential for synergy of Cbf-K16 with ceftazidime/ampicilin against MRSA, which was resistant to these two antibiotics with the minimum inhibitory concentration more than 64 μg/ml. The combinations showed a synergistic effect by a checkerboard assay with a fractional inhibitory concentration index ≤0.5. The killing curves of the combination treatment against MRSA showed that CFU counts decreased rapidly within 4 h by almost five logs, while single medication groups and the control group exhibited little inhibitory effect. In addition, in a mice bacteremia model, studies indicated that the combination treatment significantly prolonged the survival time of mice infected with MRSA, with a death protection rate of 80 %. Flow cytometry analysis and transmission electron microscopy indicated that combination- treated MRSA was completely ruptured with the cellular contents leaked out. The synergistic effect showed that Cbf-K16 selectively killed cells with non-integrity induced by cell wall inhibition antibiotics, suggesting that Cbf-K16 is a potential therapeutic agent and adjuvant for antimicrobial chemotherapy.

The inhibitory effect of sodium baicalin on oseltamivir-resistant influenza A virus via reduction of neuraminidase activity

Jing Jin,Yuanjin Chen,Dechuan Wang,Lingman Ma,Min Guo,Changlin Zhou,Jie Dou 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.6

Baicalin was identified as a neuraminidase (NA)inhibitor displaying anti-influenza A virus (IAV) activity. However, its poor solubility in saline has limited its use inthe clinic. We generated sodium baicalin and showed that itexhibited greatly increased solubility in saline. Its efficacyagainst oseltamivir-resistant mutant A/FM/1/47-H275Y(H1N1-H275Y) was evaluated in vitro and in vivo. Resultsshowed that 10 lM of sodium baicalin inhibited A/FM/1/47 (H1N1), A/Beijing/32/92 (H3N2) and H1N1-H275Y inMDCK cells in a dose-dependent manner, with inhibitoryrates of 83.9, 75.9 and 47.7%, respectively. Intravenousadministration of sodium baicalin at 100 mg/kg/d enabledthe survival of 20% of H1N1-H275Y-infected mice. Thetreatment alleviated body weight loss and lung injury. Moreover, sodium baicalin exerted a clear inhibitory effecton NAs. The IC50 values of sodium baicalin against H1N1-H275Y and cells-expressing A/Anhui/1/2013-R294K(H7N9-R294K) NA protein (N9-R294K) were 214.4 lMand 216.3 lM. Direct interactions between sodium baicalinand NA were observed, and we simulated the interactionsof sodium baicalin with N9-R294K and N9 near the activesites of OC-N9-R294K and OC-N9. The residues responsiblefor the sodium baicalin-N9-R294K and sodiumbaicalin-N9 interactions were the same, confirming thatsodium baicalin exerts effects on wild-type and oseltamivir-resistant viral strains.

Neoadjuvant Chemotherapy-Guided Bladder-Sparing Treatment for Muscle-Invasive Bladder Cancer: Results of a Pilot Phase II Study

Hongzhe Shi,Wen Zhang,Xingang Bi,Dong Wang,Zejun Xiao,Youyan Guan,Kaopeng Guan,Jun Tian,Hongsong Bai,Linjun Hu,Chuanzhen Cao,Weixing Jiang,Zhilong Hu,Jin Zhang,Yan Chen,Shan Zheng,Xiaoli Feng,Changlin 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose Reduced quality of life after cystectomy has made bladder preservation a popular research topic for muscle-invasive bladder cancer (MIBC). Previous research has indicated significant tumor downstaging after neoadjuvant chemotherapy (NAC). However, maximal transurethral resection of bladder tumor (TURBT) was performed before NAC to define the pathology, impacting the real evaluation of NAC. This research aimed to assess real NAC efficacy without interference from TURBT and apply combined modality therapies guided by NAC efficacy. Materials and Methods Patients with cT2-4aN0M0 MIBC were confirmed by cystoscopic biopsy and imaging. NAC efficacy was assessed by imaging, urine cytology, and cystoscopy with multidisciplinary team discussion. Definite responders (≤ T1) underwent TURBT plus concurrent chemoradiotherapy. Incomplete responders underwent radical cystectomy or partial cystectomy if feasible. The primary endpoint was the bladder preservation rate. Results Fifty-nine patients were enrolled, and the median age was 63 years. Patients with cT3-4 accounted for 75%. The median number of NAC cycles was three. Definite responders were 52.5%. The complete response (CR) was 10.2%, and 59.3% of patients received bladder-sparing treatments. With a median follow-up of 44.6 months, the 3-year overall survival (OS) was 72.8%. Three-year OS and relapse-free survival were 88.4% and 60.0% in the bladder-sparing group but only 74.3% and 37.5% in the cystectomy group. The evaluations of preserved bladder function were satisfactory. Conclusion After stratifying MIBC patients by NAC efficacy, definite responders achieved a satisfactory bladder-sparing rate, prognosis, and bladder function. The CR rate reflected the real NAC efficacy for MIBC. This therapy is worth verifying through multicenter research.