Read by QxMD icon Read


B Yun, T Zhang, M A K Azad, J Wang, C J Nowell, P Kalitsis, T Velkov, D F Hudson, J Li
Increasing incidence of multidrug-resistant bacteria presents an imminent risk to global health. Polymyxins are 'last-resort' antibiotics against Gram-negative 'superbugs'; however, nephrotoxicity remains a key impediment in their clinical use. Molecular mechanisms underlying this nephrotoxicity remain poorly defined. Here, we examined the pathways which led to polymyxin B induced cell death in vitro and in vivo. Human proximal tubular cells were treated with polymyxin B (12.5-100 μM) for up to 24 h and showed a significant increase in micronuclei frequency, as well as abnormal mitotic events (over 40% in treated cells, p < 0...
March 20, 2018: Archives of Toxicology
Yoshinori Sato, Yuka Unno, Tsuneyuki Ubagai, Yasuo Ono
We investigated the numbers of planktonic and biofilm cells and the expression levels of genes encoding efflux pumps and biofilm-related proteins in 10 clinical isolates of multi-drug resistant Acinetobacter baumannii (MDRA) as well as in its standard strain ATCC 19606 in the presence of colistin (CST), polymyxin B (PMB), minomycin (MIN), and tigecycline (TGC) at their respective sub-MICs. The number of planktonic and biofilm cells of ATCC 19606 decreased in the presence of all aforementioned antibiotics in a dose-dependent manner...
2018: PloS One
Rui Shi, Yuzhao Niu, Min Gong, Jingjing Ye, Wei Tian, Liqun Zhang
Bacterial infection is a major problem world-wide, especially in wound treatment where it can severely prolong the healing process. In this study, a double drug co-delivery elastic antibacterial nanocomposite was developed by combining ciprofloxacin (CPX) and polymyxin B sulfate-loaded halloysite clay nanotubes (HNTs-B) into a gelatin elastomer. CPX nanoparticles which act against both gram positive and gram-negative bacterium were dispersed directly in the matrix, and polymyxin B sulfate was loaded in HNTs and then distributed into the matrix...
June 1, 2018: Materials Science & Engineering. C, Materials for Biological Applications
Satoshi Inoue, Yuichiro Sakamoto, Hiroyuki Koami, Kosuke Yamada C, Futoshi Nagashima, Toru Miike, Takashi Iwamura, Toru Obata
PURPOSE: The aim of this study was to identify a useful biomarker to predict the efficacy of polymyxin B-immobilized fiber direct hemoperfusion (PMX-DHP) in patients with septic shock. METHODS: The 44 patients included in this study were divided into two groups. Group A had an increase in systolic blood pressure (SBP) over 30 mmHg after PMX-DHP treatment. Group B had an increase in SBP less than 30 mmHg after PMX-DHP treatment. We evaluated the clinical characteristics and demographics of both groups...
2018: Journal of Nippon Medical School, Nippon Ika Daigaku Zasshi
Yue Li, Liqiang Liu, Shanshan Song, Hua Kuang, Chuanlai Xu
Increasing attention is now being directed to the utilization of polymyxin B (PMB) as a last-line treatment for life-threatening infections caused by multidrug resistant Gram-negative bacteria. Unfortunately, polymyxins resistance is also increasingly reported, leaving a serious threat to human health. Therefore, the establishment of rapid detection methods for PMB residues is highly essential to ensure public health. In this study, two monoclonal antibodies (mAb; 2A2 and 3C6) were obtained using PMB-bovine serum albumin as the immunogen and PMB-ovalbumin as the coating antigen, which were prepared with N -(γ-maleimidobutyryloxy) succinimide ester and glutaraldehyde as cross-linking agents, respectively...
March 5, 2018: Nanomaterials
Sybil Obuobi, Zhi Xiang Voo, Mei W Low, Bertrand Czarny, Vanitha Selvarajan, Nor L Ibrahim, Yi Yan Yang, Pui Lai Rachel Ee
While physically crosslinked polycarbonate hydrogels are effective drug delivery platforms, their hydrophobic nature and lack of side chain functionality or affinity ligands for controlled release of hydrophilic drugs underscore the importance of their chemical compositions. This study evaluates an array of anionic hydrogel systems of phenylboronic acid functionalized triblock copolymers prepared via reversible physical interactions. Variation of key chemical functionalities while maintaining similar core structural features demonstrates the influence of the substitution position and protection of the boronic acid functionality on gel viscoelasticity and mechanical strength at physiological pH...
March 6, 2018: Advanced Healthcare Materials
Qiuxia Ma, Yong Huang, Jian Wang, Xuebin Xu, Jane Hawkey, Chaojie Yang, Beibei Liang, Xiaofeng Hu, Fuli Wu, Xiaoxia Yang, Jinyan Wang, Rongrui Li, Peng Li, Jing Xie, Leili Jia, Ligui Wang, Rongzhang Hao, Yigang Tong, Kathryn E Holt, Shaofu Qiu, Yansong Sun, Hongbin Song
Since the plasmid-mediated polymyxin resistance gene mcr-1 was first reported in Escherichia coli and Klebsiella pneumoniae in China, only one mcr-1-positive isolate of Shigella sonnei, containing inactivated mcr-1, has been reported worldwide. Here, we screened 1650 historical S. sonnei strains isolated from 2003 to 2015 in China for mcr-1. We determined the antimicrobial susceptibilities and resistance genes of mcr-1-positive isolates and investigated the transferability of polymyxin resistance by plasmid conjugation...
February 28, 2018: International Journal of Antimicrobial Agents
Manjulika Shukla, Isha Soni, Karen Matsuyama, Tran Tran, Mary Tanga, Leyi Gong, Sidharth Chopra
INTRODUCTION: Multidrug-resistant Acinetobacter baumannii (MDR-AB) is one of the most significant nosocomial pathogens, that is increasingly being isolated in healthcare settings worldwide. Owing to its inherent drug-resistant nature, coupled with its ability to readily acquire resistance to other antibiotic classes, there is a real dearth of antibiotics available to treat infections with MDR-AB. MATERIALS AND METHODS: A commercially available library was screened against MDR-AB BAA-1605 to identify novel inhibitory molecules...
February 28, 2018: International Journal of Antimicrobial Agents
Eduardo C Gomes, Diego R Falci, Pedro Bergo, Alexandre P Zavascki, Maria Helena Rigatto
OBJECTIVES: To evaluate the impact of polymyxin B (PMB)- associated Acute Kidney Injury (AKI) in 1-year mortality and renal function recovery. METHODS: Patients >18 years old who survived the first 30-days after PMB therapy were followed for 1-year. The impact of AKI and Renal Failure (using RIFLE score) in 1-year mortality was analyzed, along with other confounding variables. Variables with a P value ≤0.2 were included in a forward stepwise Cox regression model...
March 1, 2018: International Journal of Antimicrobial Agents
Vincenzo Pota, Maria Beatrice Passavanti, Pasquale Sansone, Maria Caterina Pace, Filomena Peluso, Alfonso Fiorelli, Caterina Aurilio
BACKGROUND: Descending necrotizing mediastinitis is a common and progressive polymicrobial infection involving the neck and chest with a high death rate (10 to 40%). From a microbiological point of view, descending necrotizing mediastinitis is sustained by Gram-positive bacteria (43-62%), anaerobes (46-78%), and, rarely, Gram-negative bacteria. Data collected during the Antibiotic Resistance-Istituto Superiore di Sanità project confirmed that Italy is positioned among the countries with the highest levels of resistance in most pathogenic species under surveillance...
March 3, 2018: Journal of Medical Case Reports
Zackery P Bulman, Miao Zhao, Michael J Satlin, Liang Chen, Barry N Kreiswirth, Thomas J Walsh, Roger L Nation, Jian Li, Brian T Tsuji
Polymyxin B and fosfomycin are two 'old' antibiotics that consistently maintain activity against Klebsiella pneumoniae carbapenemase (KPC)-producing organisms based on in vitro susceptibility testing. However, each antibiotic's use in monotherapy has been associated with high rates of treatment failure. Therefore, our objective was to investigate the combinatorial pharmacodynamics of polymyxin B and fosfomycin against KPC-producing K. pneumoniae. Polymyxin B front-loading (3.33 mg/kg for 1 dose followed by 1...
February 24, 2018: International Journal of Antimicrobial Agents
Martti Vaara
Polymyxin B and colistin (polymyxin E) are bactericidal pentacationic lipopeptides that act specifically on Gram-negative bacteria, first by disrupting their outermost permeability barrier, the outer membrane (OM), and then damaging the cytoplasmic membrane. The discovery of both polymyxin B and colistin was published independently by three laboratories as early as in 1947. They were subsequently used in intravenous therapy. Unfortunately, they also exhibit significant and dose-limiting nephrotoxicity. Therefore, polymyxins were reserved as agents of last-line defense...
February 27, 2018: Medicinal Research Reviews
Aiko Okubo, Ayumu Nakashima, Shigehiro Doi, Toshinori Ueno, Kensuke Sasaki, Takashi Esaki, Takao Masaki
BACKGROUND: The definition of sepsis was updated to sepsis-3 in February 2016. Currently, direct hemoperfusion therapy using the polymyxin B-immobilized fiber cartridge (PMX-DHP) is widely performed to treat sepsis and septic shock. However, the prognostic factors of PMX-DHPs in patients with sepsis using the new definition are unclear. We retrospectively assessed prognostic factors in patients who had received PMX-DHP therapy for sepsis and septic shock. METHODS: We included 71 patients with severe infection who underwent PMX-DHP treatment from January 2006 to August 2015 in this study...
February 24, 2018: Clinical and Experimental Nephrology
Ming Lu, Jian-Ri Li, Lery Alvarez-Lugo, Yan Li, Shan Yu, Xuanhao Li, Benkang Shi, Toby C Chai
Bladder urothelium plays an active role in response to bacterial infection. There is little known about the electrophysiological activity in urothelial cells in this process. We used a non-enzymatic method to isolate bladder urothelial tissue and to patch clamp umbrella cells in situ. A 200pS conductance potassium (K+ ) channel was detected from female C57BL6 mice. Of 58 total patches, 17.2% patches displayed the 200pS K+ conductance channel. This K+ conductance channel showed Ca2+ sensitivity and voltage dependence...
February 21, 2018: American Journal of Physiology. Cell Physiology
M N Islam, D Ahmed, M A Hossain, C R Ahsan, M Yasmin
Antimicrobial drug resistance, a global concern, has been increasing unpredictably in microorganism causing human infections specially among Gram negative non-fermenting Pseudomonas spp. Carbapenems, a beta lactam antibiotics, are the most potent and effective drug usually kept reserved for treating the multi-drug resistant Psedomonas spp and other infections caused by organisms producing Extended Spectrum Beta Lactamase (ESBL) and AmpC. Clinical utility of carbapenem will reduce when resistant bacteria evolve due to production of carbapenem hydrolyzing Metallo-β-lactamase (MBL) which confers high-level resistance to all beta-lactam antibiotics except aztreonam...
January 2018: Mymensingh Medical Journal: MMJ
Wei Guo, Shao-Chun Guo, Min Li, Li-Hong Li, Yan Qu
Background: Acinetobacter baumannii nosocomial ventriculitis/meningitis, especially those due to drug-resistant strains, has substantially increased over recent years. However, limited therapeutic options exist for the Acinetobacter baumannii ventriculitis/meningitis because of the poor penetration rate of most antibiotics through the blood-brain barrier. Case presentation: A 57-year-old male patient developed ventriculitis from an extensively drug-resistant strain of Acinetobacter baumannii after the decompressive craniectomy for severe traumatic brain injury...
2018: Antimicrobial Resistance and Infection Control
Sandra S Richter, James Karichu, Joshua Otiso, Hillary Van Heule, George Keller, Eric Cober, Laura J Rojas, Andrea M Hujer, Kristine M Hujer, Steve Marshall, Frederico Perez, Susan D Rudin, T Nicholas Domitrovic, Keith S Kaye, Robert Salata, David van Duin, Robert A Bonomo
Colistin and polymyxin B MICs were determined for 106 carbapenem-resistant Klebsiella pneumoniae (CR-Kp) isolates using Sensititre Research Use Only GNX2F plates (Thermo Fisher) and compared to CLSI broth macrodilution (BMD) as the reference method. For colistin, EUCAST breakpoints were applied and testing of isolates with very major (VM) errors was repeated in duplicate by both methods to determine a majority result. Essential agreement (MIC ± one dilution) of GNX2F with the reference method was 97.1% for polymyxin B and 92...
January 9, 2018: Diagnostic Microbiology and Infectious Disease
Francesco Di Virgilio, Anna L Giuliani, Valentina Vultaggio-Poma, Simonetta Falzoni, Alba C Sarti
The P2X7 receptor (P2X7R) is a ligand-gated plasma membrane ion channel belonging to the P2X receptor subfamily activated by extracellular nucleotides. General consensus holds that the physiological (and maybe the only) agonist is ATP. However, scattered evidence generated over the last several years suggests that ATP might not be the only agonist, especially at inflammatory sites. Solid data show that NAD + covalently modifies the P2X7R of mouse T lymphocytes, thus lowering the ATP threshold for activation...
2018: Frontiers in Pharmacology
Hanae Tsukumo, Natsumi Matsunari, Kunihiko Yamashita, Hajime Kojima, Hiroshi Itagaki
It was believed that high molecular weight molecules including proteins cannot penetrate the skin. However, protein penetration through disrupted/ruptured skin has been reported recently, thus carrying the potential for inducing an allergic response. We used the human Cell Line Activation Test (h-CLAT), an in vitro skin sensitization test, to assess the allergic potential of proteins by measuring levels of CD86 and CD54 in the human monocytic leukemia cell line THP-1. Six allergens including ovalbumin (OVA) and human serum albumin (HSA; negative control) upregulated CD86 and/or CD54; a false-positive result was obtained using HSA...
February 10, 2018: Journal of Pharmacological and Toxicological Methods
Lucy J Bock, Charlotte K Hind, J Mark Sutton, Matthew E Wand
The effectiveness of several cationic disinfectants as well as colistin and polymyxin B were assessed under different growth conditions against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa strains. These conditions included different media (MH1, MH2, TSB and LB) and plate material (polypropylene and polystyrene). Results showed that MIC/MBC values of colistin and polymyxin B were significantly lower on polypropylene plates when compared to polystyrene plates regardless of media used. There were also differences for MIC/MBC values to certain biocides e...
February 12, 2018: Letters in Applied Microbiology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"