Read by QxMD icon Read

Bacterial resistance

Shunjie Yan, Lingjie Song, Shifang Luan, Zhirong Xin, Shanshan Du, Hengchong Shi, Shuaishuai Yuan, Yuming Yang, Jinghua Yin
Bacterial infections are problematic in many healthcare-associated devices. Antibacterial surfaces integrating the strength of bacteria repellent and bactericidal functions exhibit an encouraging efficacy in tackling this problem. Herein, a hierarchical dual-function antibacterial polymer brush coating that integrates an antifouling bottom layer with a bactericidal top layer is facilely constructed via living photograft polymerization. Excellent resistance to bacterial attachment is correlated with the antifouling components, and good bactericidal activity is afforded by the bactericidal components, and therefore the hierarchical coating shows an excellent long-term antibacterial capability...
August 12, 2016: Colloids and Surfaces. B, Biointerfaces
T Didbaridze, L Saginashvili, L Akhmeteli, B Iremashvili, N Gogokhia
This study provides a contemporary epidemiology of aspirates taken during surgery from the abdominal cavity among patients with bacterial peritonitis to identify the isolates and study their sensitivity to antibiotics. Our bacteriology investigations included isolation of poor cultures, and detection of microbes was conducted using a rapid identification system (API20E, API Staph, API Strep, API Ana, BioMerieux). Rapid tests for detection of oxidase and catalase activity were also used. Susceptibility of microorganisms to antibiotics was defined by the disc-diffusion method using standard discs (EUCAST guidelines 2015) according to Clinical Laboratory Standard Institute (CLSI) protocols (ATB strips: ATB G, ATB Staph, ATBANA, ATBPse, ATBStrep...
September 2016: Georgian Medical News
Fuqin Zou, Dong Zeng, Bin Wen, Hao Sun, Yi Zhou, Mingyue Yang, Zhirong Peng, Shuai Xu, Hesong Wang, Xiangchao Fu, Dan Du, Yan Zeng, Hui Zhu, Kangcheng Pan, Bo Jing, Ping Wang, Xueqin Ni
Antibiotics have been widely used for the prevention and the treatment of diseases to humans and animals, and they have fed additives for agricultural animals to promote growth. However, there is a growing concern over the practice due to its side effects on intestinal microbial communities which plays a vital role in animals' health. To investigate the effect of antibiotics on the bacterial population of the caecum in rex rabbits, 80 rex rabbits were randomly divided into four groups: control group (B, basal diet), chlortetracycline group (C, 50 mg/kg), colistin sulfate group (S, 20 mg/kg) and zinc bacitracin group (Z, 40 mg/kg)...
December 2016: AMB Express
Bartosz Roszniowski, Agnieszka Latka, Barbara Maciejewska, Dieter Vandenheuvel, Tomasz Olszak, Yves Briers, Giles S Holt, Miguel A Valvano, Rob Lavigne, Darren L Smith, Zuzanna Drulis-Kawa
Burkholderia phage AP3 (vB_BceM_AP3) is a temperate virus of the Myoviridae and the Peduovirinae subfamily (P2likevirus genus). This phage specifically infects multidrug-resistant clinical Burkholderia cenocepacia lineage IIIA strains commonly isolated from cystic fibrosis patients. AP3 exhibits high pairwise nucleotide identity (61.7 %) to Burkholderia phage KS5, specific to the same B. cenocepacia host, and has 46.7-49.5 % identity to phages infecting other species of Burkholderia. The lysis cassette of these related phages has a similar organization (putative antiholin, putative holin, endolysin, and spanins) and shows 29-98 % homology between specific lysis genes, in contrast to Enterobacteria phage P2, the hallmark phage of this genus...
October 21, 2016: Applied Microbiology and Biotechnology
Mustafa Nakipoğlu, Fadime Yilmaz, Bulent Icgen
Untreated wastewaters and treated effluents even after final disinfection contain antibiotic resistant bacteria and resistance genes before they are released into surface waters. A correlation between resistant bacteria and antibiotics in surface waters has been found, as have antibiotic resistance genes. Of particular interest are vancomycin-resistant enterococci harboring vanA gene that confers high level of resistance to glycopeptide antibiotics including teicoplanin. Therefore, in this study, river water samples were analysed to investigate vancomycin- and teicoplanin-resistant bacterial isolates harboring vanA gene...
October 21, 2016: Bulletin of Environmental Contamination and Toxicology
Daniel Nichol, Mark Robertson-Tessi, Peter Jeavons, Alexander R A Anderson
Non-genetic variation in phenotypes, or bet-hedging, has been observed as a driver of drug resistance in both bacterial infections and cancers. Here, we study how bet-hedging emerges in the genotype-phenotype mapping through a simple interaction model: a molecular switch. We use simple Chemical Reaction Networks to implement stochastic switches that map gene products to phenotypes and investigate the impact of structurally distinct mappings on the evolution of phenotypic heterogeneity. Bet-hedging naturally emerges within this model and is robust to evolutionary loss through mutations to both the expression of individual genes and to the network itself...
October 21, 2016: Genetics
Héloïse Coté, Marie-Anne Boucher, André Pichette, Benoit Roger, Jean Legault
ETHNOPHARMACOLOGICAL RELEVANCE: Oleoresin of Abies balsamea (L.) Mill. was used by Aboriginal people of the boreal forest of Canada and French Canadians to treat various infections, suggesting that oleoresin has antibacterial properties. AIM OF THE STUDY: In this study, the antibacterial activity of whole oleoresin from A. balsamea was investigated against E. coli, S. aureus and two methicillin-resistant S. aureus (MRSA) strains using a new sensitive assay developed to evaluate hydrophobic matrix and compounds...
October 18, 2016: Journal of Ethnopharmacology
Arzu Tatar, Mukadder Korkmaz, Muhammed Yayla, Elif Polat, Hakan Uslu, Zekai Halici, Secil N Parlak
INTRODUCTION: For the treatment of rhinosinusitis antibiotics are used frequently. Concerns have been raised regarding the adverse effects of antibiotics and growing resistance. The lack of discovery of new antibiotic compounds has increased the necessity for exploration of non-antibiotic compounds that have antibacterial activity. Amlodipine is a non-antibiotic compound with anti-inflammatory activity. OBJECTIVE: In this study we aimed to investigate the potential role of amlodipine in treatment of rhinosinusitis by evaluating its effects on tissue oxidative status, mucosal histology and inflammation...
September 28, 2016: Brazilian Journal of Otorhinolaryngology
J F Leal, I S Henriques, A Correia, E B H Santos, V I Esteves
Oxytetracycline (OTC) is one of the most used antibiotics in aquaculture. The main concern related to its use is the bacterial resistance, when ineffective treatments are applied for its removal or inactivation. OTC photo-degradation has been suggested as an efficient complementary process to conventional methods used in intensive fish production (e.g.: ozonation). Despite this, and knowing that the complete mineralization of OTC is difficult, few studies have examined the antibacterial activity of OTC photoproducts...
October 18, 2016: Environmental Pollution
Sanjib K Shrestha, Liliia M Kril, Keith D Green, Stefan Kwiatkowski, Vitaliy M Sviripa, Justin R Nickell, Linda P Dwoskin, David S Watt, Sylvie Garneau-Tsodikova
The emergence of multidrug-resistant bacterial and fungal strains poses a threat to human health that requires the design and synthesis of new classes of antimicrobial agents. We evaluated bis(N-amidinohydrazones) and N-(amidino)-N'-aryl-bishydrazones for their antibacterial and antifungal activities against panels of Gram-positive/Gram-negative bacteria as well as fungi. We investigated their potential to develop resistance against both bacteria and fungi by a multi-step resistance-selection method, explored their potential to induce the production of reactive oxygen species, and assessed their toxicity...
October 10, 2016: Bioorganic & Medicinal Chemistry
Jeremiah Seni, Enock Sweya, Amri Mabewa, Stephen E Mshana, Japhet M Gilyoma
BACKGROUND: Secondary peritonitis is a common surgical emergence with deadly outcomes when not timely and promptly intervened. The emergence of Extended spectrum beta lactamase producing bacteria (ESBL) poses treatment challenge at Bugando Medical Centre (BMC); hence a need to evaluate the magnitude of ESBL so as to guide specific therapy. METHODS: This was a cross sectional study conducted at BMC from May 2014 to April 2015 involving patients with secondary peritonitis...
October 21, 2016: BMC Emergency Medicine
Pierre Dehoux, Jean Christophe Marvaud, Amr Abouelleil, Ashlee M Earl, Thierry Lambert, Catherine Dauga
BACKGROUND: Clostridium bolteae and Clostridium clostridioforme, previously included in the complex C. clostridioforme in the group Clostridium XIVa, remain difficult to distinguish by phenotypic methods. These bacteria, prevailing in the human intestinal microbiota, are opportunistic pathogens with various drug susceptibility patterns. In order to better characterize the two species and to obtain information on their antibiotic resistance genes, we analyzed the genomes of six strains of C...
October 21, 2016: BMC Genomics
Yu Cheng, Srinivasa Rao Avula, Wei-Wei Gao, Dinesh Addla, Vijai Kumar Reddy Tangadanchu, Ling Zhang, Jian-Mei Lin, Cheng-He Zhou
A series of new potentially multi-targeting antimicrobial 2-aminothiazolyl quinolones were designed, synthesized and characterized by (1)H NMR, (13)C NMR, IR, MS and HRMS spectra. Bioactive assay manifested that some of the prepared compounds showed moderate to good antibacterial and antifungal activities. Noticeably, compound 10f could effectively inhibit the growth of B. typhi and MRSA with MIC values of 1 and 8 μg/mL, respectively. Experimental results revealed that compound 10f was membrane-active and had the ability to rapidly kill the tested strains and effectively prevent the development of bacterial resistance...
October 7, 2016: European Journal of Medicinal Chemistry
Troy A Skwor, Stephanie Klemm, Hanyu Zhang, Brianna Schardt, Stephanie Blaszczyk, Matthew A Bork
Increasing rates of antibiotic resistance coupled with the lack of novel antibiotics threatens proper clinical treatment and jeopardizes their use in prevention. A photodynamic approach appears to be an innovative treatment option, even for multi-drug resistant strains of bacteria. Three components are utilized in photodynamic inactivation: a photosensitizer, light source, and oxygen. Variations in photosensitizers strongly influence microbial binding and bactericidal activity. In this study, four different cationic metalloporphyrins (Cu(2+), Fe(2+), Pd(2+), Zn(2+)) were compared to the free-base ligand 5,10,15,20-tetrakis(N-methylpyridinium-4-yl)porphyrin regarding their electronic properties and generation of reactive oxygen species upon subsequent 405nm violet-blue irradiation...
October 15, 2016: Journal of Photochemistry and Photobiology. B, Biology
Narges Abdali, Jerry Matthew Parks, Keith Haynes, Julie L Chaney, Adam T Green, David Wolloscheck, John K Walker, Valentin V Rybenkov, Jerome Yves Baudry, Jeremy C Smith, Helen I Zgurskaya
Antibiotic resistance is a major threat to human welfare. Inhibitors of multidrug efflux pumps (EPIs) are promising alternative therapeutics that could revive activities of antibiotics and reduce bacterial virulence. Identification of new druggable sites for inhibition is critical for development of effective EPIs, especially in light of constantly emerging resistance. Here, we describe EPIs that interact with periplasmic membrane fusion proteins, critical components of efflux pumps that are responsible for the activation of the transporter and the recruitment of the outer-membrane channel...
October 21, 2016: ACS Infectious Diseases
Michael R Gillings, Ian T Paulsen, Sasha G Tetu
Antibiotic resistance arises as a consequence of complex interactions among genes, mobile elements, and their bacterial hosts, coupled with the intense selection pressures imposed by humans in an attempt to control bacterial growth. Understanding the evolution of resistance requires an understanding of interacting cellular and genetic components. Here, we review how DNA analysis has helped reconstruct the origins of the mosaic, multiresistant mobile elements that have spread through pathogens in the last 60 years...
October 21, 2016: Annals of the New York Academy of Sciences
Issmat I Kassem, Olugbenga Kehinde, Anand Kumar, Gireesh Rajashekara
Poultry is a major source of Campylobacter, which can cause foodborne bacterial gastroenteritis in humans. Additionally, poultry-associated Campylobacter can develop resistance to important antimicrobials, which increases the risk to public health. While broiler chickens have been the focus of many studies, the emergence of antimicrobial-resistant Campylobacter on layer farms has not received equal attention. However, the growing popularity of cage-free and organic layer farming necessitates a closer assessment of (1) the impact of these farming practices on the emergence of antimicrobial-resistant Campylobacter and (2) layers as a potential source for the transmission of these pathogens...
September 22, 2016: Foodborne Pathogens and Disease
Po C Liu, Yi T Lee, Chun Y Wang, Ya-Tang Yang
We describe a low cost, configurable morbidostat for characterizing the evolutionary pathway of antibiotic resistance. The morbidostat is a bacterial culture device that continuously monitors bacterial growth and dynamically adjusts the drug concentration to constantly challenge the bacteria as they evolve to acquire drug resistance. The device features a working volume of ~10 ml and is fully automated and equipped with optical density measurement and micro-pumps for medium and drug delivery. To validate the platform, we measured the stepwise acquisition of trimethoprim resistance in Escherichia coli MG 1655, and integrated the device with a multiplexed microfluidic platform to investigate cell morphology and antibiotic susceptibility...
September 27, 2016: Journal of Visualized Experiments: JoVE
Jean-Emmanuel Hugonnet, Dominique Mengin-Lecreulx, Alejandro Monton, Tanneke den Blaauwen, Etienne Carbonnelle, Carole Veckerlé, Yves Brun, Michael van Nieuwenhze, Christiane Bouchier, Kuyek Tu, Louis B Rice, Michel Arthur
The target of β-lactam antibiotics is the D,D-transpeptidase activity of penicillin-binding proteins (PBPs) for synthesis of 4→3 cross-links in the peptidoglycan of bacterial cell walls. Unusual 3→3 cross-links formed by L,D-transpeptidases were first detected in Escherichia coli more than four decades ago, however no phenotype has previously been associated with their synthesis. Here we show that production of the L,D-transpeptidase YcbB in combination with elevated synthesis of the (p)ppGpp alarmone by RelA lead to full bypass of the D,D-transpeptidase activity of PBPs and to broad-spectrum β-lactam resistance...
October 21, 2016: ELife
Mark Shepherd, Maud E S Achard, Adi Idris, Makrina Totsika, Minh-Duy Phan, Kate M Peters, Sohinee Sarkar, Cláudia A Ribeiro, Louise V Holyoake, Dimitrios Ladakis, Glen C Ulett, Matthew J Sweet, Robert K Poole, Alastair G McEwan, Mark A Schembri
Nitric oxide (NO) is a toxic free radical produced by neutrophils and macrophages in response to infection. Uropathogenic Escherichia coli (UPEC) induces a variety of defence mechanisms in response to NO, including direct NO detoxification (Hmp, NorVW, NrfA), iron-sulphur cluster repair (YtfE), and the expression of the NO-tolerant cytochrome bd-I respiratory oxidase (CydAB). The current study quantifies the relative contribution of these systems to UPEC growth and survival during infection. Loss of the flavohemoglobin Hmp and cytochrome bd-I elicit the greatest sensitivity to NO-mediated growth inhibition, whereas all but the periplasmic nitrite reductase NrfA provide protection against neutrophil killing and promote survival within activated macrophages...
October 21, 2016: Scientific Reports
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"