Objective: To explore the characterization and frequency of antibiotic resistance related to membrane porin and efflux pump genes among Acinetobacter baumannii (A. baumannii) strains obtained from burn patients in Teh...Objective: To explore the characterization and frequency of antibiotic resistance related to membrane porin and efflux pump genes among Acinetobacter baumannii (A. baumannii) strains obtained from burn patients in Tehran, Iran. Methods: In this cross-sectional descriptive study, 100 strains of A. baumannii isolated from burn patients visiting teaching hospitals of Tehran were collected from January 2016 to November 2017. After A. baumannii strains were confirmed, antimicrobial susceptibility testing was done via Kirby-Bauer disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines. PCR amplification was performed for detection of β-lactamase adeR, OprD, adeS genes among A. baumannii strains. Results: All isolates (100%) were resistant to ceftazidime, cefotaxime, cefepime, ciprofloxacin, and piperacillin, and most isolates indicated high resistance (95%-97%) to meropenem, imipenem, gentamicin, ceftriaxone, trimethoprim-sulfamethoxazole, piperacillin-tazobactam, amikacin, and tetracycline. The most effective antibiotic against A. baumannii isolates was colistin (97% sensitivity), followed by tigecycline. The frequency of OprD, adeS, and adeR genes were 98%, 91%, and 77%, respectively. Conclusions: This study shows that the majority of A. baumannii isolates are highly resistant to the antibiotics most commonly used in burn patients. Also, high distribution of OprD and adeRS genes may be responsible for the observed resistances among A. baumannii isolates that demonstrate the possible role of both efflux pumps in simultaneous of carbapenemase production during antibiotic resistance.展开更多
The Optimum use of energy is one of the significant needs in wireless sensor networks, because sensor devices would usually use the battery power. In this article, we give the suggested routing algorithm (BSDCH) with ...The Optimum use of energy is one of the significant needs in wireless sensor networks, because sensor devices would usually use the battery power. In this article, we give the suggested routing algorithm (BSDCH) with determining an optimum routine due to the energy use and the number of passed hobs. To transfer date from nodes’ sensor to BS (Base Station), data sending has been utilized in chains. In BSDCH algorithm, the nodes’ space is divided into several regions. In this article, each part is called a cluster. In each cluster, a node which is the best due to energy and distance comparison with other cluster nodes it is continuously selected with a given Formula (4) which is called main CH (Cluster Head) and forms a chain in that cluster and in each node cluster, it is selected by Formula (5) as secondary CH with the least distance and the best situation to BS and main CH. the secondary CH task is to receive data from the main CH and send data to the BS. As far as the main cluster head would waste too much energy to send data to BS, so to send data through secondary CH, we can keep main CH energy for more time. In the time of sending data from nodes to main CH, a multi chain is utilized. In the time of making nodes’ chain, nods are connected straight into its main CH radius and other nodes are connected in their sending radius which would have the least distance to main CH. Finally, also, BSDCH has been compared with PEGASIS [1] and PDCH [2]. The simulation results are shown which are indicator of a better BSDCH performance.展开更多
文摘Objective: To explore the characterization and frequency of antibiotic resistance related to membrane porin and efflux pump genes among Acinetobacter baumannii (A. baumannii) strains obtained from burn patients in Tehran, Iran. Methods: In this cross-sectional descriptive study, 100 strains of A. baumannii isolated from burn patients visiting teaching hospitals of Tehran were collected from January 2016 to November 2017. After A. baumannii strains were confirmed, antimicrobial susceptibility testing was done via Kirby-Bauer disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines. PCR amplification was performed for detection of β-lactamase adeR, OprD, adeS genes among A. baumannii strains. Results: All isolates (100%) were resistant to ceftazidime, cefotaxime, cefepime, ciprofloxacin, and piperacillin, and most isolates indicated high resistance (95%-97%) to meropenem, imipenem, gentamicin, ceftriaxone, trimethoprim-sulfamethoxazole, piperacillin-tazobactam, amikacin, and tetracycline. The most effective antibiotic against A. baumannii isolates was colistin (97% sensitivity), followed by tigecycline. The frequency of OprD, adeS, and adeR genes were 98%, 91%, and 77%, respectively. Conclusions: This study shows that the majority of A. baumannii isolates are highly resistant to the antibiotics most commonly used in burn patients. Also, high distribution of OprD and adeRS genes may be responsible for the observed resistances among A. baumannii isolates that demonstrate the possible role of both efflux pumps in simultaneous of carbapenemase production during antibiotic resistance.
文摘The Optimum use of energy is one of the significant needs in wireless sensor networks, because sensor devices would usually use the battery power. In this article, we give the suggested routing algorithm (BSDCH) with determining an optimum routine due to the energy use and the number of passed hobs. To transfer date from nodes’ sensor to BS (Base Station), data sending has been utilized in chains. In BSDCH algorithm, the nodes’ space is divided into several regions. In this article, each part is called a cluster. In each cluster, a node which is the best due to energy and distance comparison with other cluster nodes it is continuously selected with a given Formula (4) which is called main CH (Cluster Head) and forms a chain in that cluster and in each node cluster, it is selected by Formula (5) as secondary CH with the least distance and the best situation to BS and main CH. the secondary CH task is to receive data from the main CH and send data to the BS. As far as the main cluster head would waste too much energy to send data to BS, so to send data through secondary CH, we can keep main CH energy for more time. In the time of sending data from nodes to main CH, a multi chain is utilized. In the time of making nodes’ chain, nods are connected straight into its main CH radius and other nodes are connected in their sending radius which would have the least distance to main CH. Finally, also, BSDCH has been compared with PEGASIS [1] and PDCH [2]. The simulation results are shown which are indicator of a better BSDCH performance.
