Read by QxMD icon Read


Sandrine Alibert, Joannah N'Gompazza Diarra, Jessica Hernandez, Aurélien Stutzmann, Marwa Fouad, Gérard Boyer, Jean-Marie Pagès
Worrying levels of bacterial resistance have been reported worldwide involving the failure of many available antibiotic treatments. Multidrug resistance (MDR) in Gram-negative bacteria is often ascribed to the presence of multiple and different resistance mechanisms in the same strain. RND efflux pumps play a major role and are an attractive target to discover new antibacterial drugs. Areas covered: This review discusses the prevalence of efflux pumps, their overexpression in clinical scenarios, their polyselectivity, their effect on the intracellular concentrations of various antibiotics associated with the alteration of the membrane permeability and their involvement in pathogenicity are discussed...
October 20, 2016: Expert Opinion on Drug Metabolism & Toxicology
Kyle A Tipton, Marjan Farokhyfar, Philip N Rather
Colony opacity phase variation in Acinetobacter baumannii strain AB5075 is regulated by a reversible high-frequency switch. Transposon mutagenesis was used to generate mutations that decreased the opaque to translucent switch and a gene encoding a predicted periplasmic membrane fusion component of a resistance-nodulation-cell division (RND)-type efflux system was isolated. This gene was designated arpA and immediately downstream was a gene designated arpB that encodes a predicted membrane transporter of RND-type systems...
October 19, 2016: MicrobiologyOpen
Zhe-Xian Tian, Xue-Xian Yi, Anna Cho, Fergal O'Gara, Yi-Ping Wang
Resistance-Nodulation-Division (RND) efflux pumps are responsible for multidrug resistance in Pseudomonas aeruginosa. In this study, we demonstrate that CpxR, previously identified as a regulator of the cell envelope stress response in Escherichia coli, is directly involved in activation of expression of RND efflux pump MexAB-OprM in P. aeruginosa. A conserved CpxR binding site was identified upstream of the mexA promoter in all genome-sequenced P. aeruginosa strains. CpxR is required to enhance mexAB-oprM expression and drug resistance, in the absence of repressor MexR, in P...
October 2016: PLoS Pathogens
Qing Lin, Langping Tan, Yu Zhou, Quanbo Zhou, Rufu Chen
OBJECTIVE: To explore the clinical value of the radical nerve dissection (RND) for the carcinoma of head of pancreas (CHP). METHODS: The clinical and pathological data of 30 CHP patients who underwent RND in our hospital were retrospectively analyzed, with an attempt to explore the safety and short-term efficacy of this procedure. RESULTS: Among these 30 patients, the operative time was (351±61) min, the intra-operative blood loss was 350 (range, 300-600) mL, and the grades B and C pancreatic fistula was 23...
August 2016: Chinese Journal of Cancer Research, Chung-kuo Yen Cheng Yen Chiu
Abigail T Ntreh, Jon W Weeks, Logan M Nickels, Helen I Zgurskaya
: TriABC-OpmH is an efflux pump from Pseudomonas aeruginosa with an unusual substrate specificity and protein composition. When overexpressed, this pump confers a high level of resistance to biocide triclosan and the detergent SDS, which are commonly used in combinations for antimicrobial treatments. This activity requires an RND transporter TriC, an outer membrane channel OpmH and two periplasmic membrane fusion proteins TriA and TriB with non-equivalent functions. In the active complex, TriA is responsible for the recruitment of OpmH, while TriB is responsible for stimulation of the transporter TriC...
September 19, 2016: Journal of Bacteriology
Juan Manriquez, Laura Giesen, Constanza Del Puerto, Sergio Gonzalez
A 54 year-old woman with a 3-year history of rheumatoid arthritis (RA) consulted us because of weight loss, fever and skin eruption. On physical examination, erythematous plaques with a pseudo-vesicular appearance were seen on the back of both shoulders. Histological examination was consistent with rheumatoid neutrophilic dermatosis (RND). After 3 days of prednisone treatment, the skin eruption resolved. RND is a rare cutaneous manifestation of seropositive RA, characterized by asymptomatic, symmetrical erythematous plaques with a pseudo-vesicular appearance...
July 2016: Anais Brasileiros de Dermatologia
David A Calhoun
No abstract text is available yet for this article.
September 20, 2016: Circulation
Christian Chalut
Mycobacteria produce a large variety of surface-exposed lipids with unusual structures. Some of these compounds are ubiquitously present in mycobacteria and play an important role in the structural organization of the cell envelope, while others are species-specific. The biosynthesis of most of these lipids requires modular polyketide synthases (PKS) or non-ribosomal peptide synthetases (NRPS) that are intracellular, suggesting that the assembly of these compounds takes place in the cytosolic compartment or near the inner leaflet of the plasma membrane...
September 2016: Tuberculosis
F Megdiche, N Vakilzadeh, M Maillard, E Grouzmann, M Burnier, G Wuerzner
OBJECTIVE: The sympathetic nervous system is implicated in most form of hypertension. In resistant hypertension, transcatheter renal denervation (RDN) has been proposed as an adjunctive therapy to antihypertensive drugs at maximum tolerated doses. The results on blood pressure (BP) reduction have been the source of debate. Few studies have explored the effect on renal hemodynamics and tubular sodium handling. The objective was to assess these two parameters before RND and after 1 and 12 months...
September 2016: Journal of Hypertension
Debarati Choudhury, Anupam Das Talukdar, Pankaj Chetia, Amitabha Bhattacharjee, Manabendra Dutta Choudhury
AIM AND OBJECTIVE: Overexpression of efflux pumps belonging to the Resistance Nodulation cell Division (RND) family is the most important intrinsic resistance mechanism of Pseudomonas aeruginosa. Hence, it is imperative to identify suitable efflux pump inhibitors (EPI) that can lead to increased intracellular concentration of antibiotics by blocking the pump. This study was undertaken to identify a putative plant based efflux pump inhibitor for RND efflux pump of P. aeruginosa. MATERIAL AND METHOD: Using molecular docking approach, 328 secondary plant metabolites have been screened for their inhibitory activity against cytoplasmic exporter protein MexB of MexAB-OprM efflux pump of P...
July 20, 2016: Combinatorial Chemistry & High Throughput Screening
Monisha Gopalani, Alisha Dhiman, Amit Rahi, Divya Kandari, Rakesh Bhatnagar
Two component systems (TCSs) can be envisaged as complex molecular devices that help the bacteria to sense its environment and respond aptly. 41 TCSs are predicted in Bacillus anthracis, a potential bioterrorism agent, of which only four have been studied so far. Thus, the intricate signaling network contributed by TCSs remains largely unmapped in B. anthracis and needs comprehensive exploration. In this study, we functionally characterized one such system composed of BAS0540 (Response regulator) and BAS0541 (Histidine kinase)...
2016: PloS One
Cristina Belgiovine, Giulio Chiesa, Ilaria Chiodi, Roberta Frapolli, Katiuscia Bonezzi, Giulia Taraboletti, Maurizio D'Incalci, Chiara Mondello
Cancer cells use two major types of movement: Mesenchymal, which is typical of cells of mesenchymal origin and depends on matrix metalloproteinase (MMP) activity, and amoeboid, which is characteristic of cells with a rounded shape and relies on the activity of Rho-associated kinase (ROCK). The present authors previously demonstrated that, during neoplastic transformation, telomerase-immortalized human fibroblasts (cen3tel cells) acquired a ROCK-dependent/MMP independent mechanism of invasion, mediated by the downregulation of the ROCK cellular inhibitor Round (Rnd)3/RhoE...
July 2016: Oncology Letters
Sirawit Pagdepanichkit, Chanwit Tribuddharat, Rungtip Chuanchuen
One hundred Acinetobacter baumannii clinical isolates were examined for inhibitory effect of reserpine and carbonyl cyanide m-chlorophenylhydrazone (CCCP) on the antimicrobial susceptibility and expression of 4 resistant-nodulation-cell division (RND)-type multidrug efflux systems, including AdeABC, AdeDE, AdeIJK, and AdeFGH, using RT-PCR. Ten A. baumannii isolates expressing AdeABC, AdeIJK, or AdeFGH were randomly selected for determination of transcription level and regulatory mutations. While all the isolates were resistant to multiple drugs, the reserpine and CCCP experiment showed that the multidrug resistance phenotype in most A...
September 2016: Canadian Journal of Microbiology
Jéssica Subirats, Alexandre Sànchez-Melsió, Carles M Borrego, José Luis Balcázar, Pascal Simonet
A metagenomics approach was applied to explore the presence of antibiotic resistance genes (ARGs) in bacteriophages from hospital wastewater. Metagenomic analysis showed that most phage sequences affiliated to the order Caudovirales, comprising the tailed phage families Podoviridae, Siphoviridae and Myoviridae. Moreover, the relative abundance of ARGs in the phage DNA fraction (0.26%) was higher than in the bacterial DNA fraction (0.18%). These differences were particularly evident for genes encoding ATP-binding cassette (ABC) and resistance-nodulation-cell division (RND) proteins, phosphotransferases, β-lactamases and plasmid-mediated quinolone resistance...
August 2016: International Journal of Antimicrobial Agents
Mark C Bates
When performed by experienced clinicians, renal nerve denervation (RND) can be done with very low risk of complication and/or acute renal injury Renal function seems to remain unchanged in this small series over 3 years More studies are needed to establish the role of renal biomarkers in assessment of acute renal injury in this setting and larger series of RND in azotemic patients should be done before the procedure indications can be expanded.
June 2016: Catheterization and Cardiovascular Interventions
Spyros Pournaras, Vasiliki Koumaki, Nicholas Spanakis, Vasiliki Gennimata, Athanassios Tsakris
During the past decades, rates of multidrug-resistant (MDR) and carbapenem-resistant (CR) Enterobacteriaceae clinical isolates, mainly Klebsiella spp., Escherichia coli, Enterobacter spp., Proteus spp. and Serratia marcescens, have increased, considerably restricting effective antimicrobial treatments. Tigecycline, the first member of the glycylcyclines, has been approved by the US Food and Drug Administration (FDA) for the treatment of complicated skin and soft-tissue, complicated intra-abdominal and community-acquired bacterial respiratory infections and is increasingly administered against MDR Enterobacteriaceae...
July 2016: International Journal of Antimicrobial Agents
Eun-Jeong Yoon, Viviane Balloy, Laurence Fiette, Michel Chignard, Patrice Courvalin, Catherine Grillot-Courvalin
UNLABELLED: Overexpression of chromosomal resistance-nodulation-cell division (RND)-type efflux systems with broad substrate specificity contributes to multidrug resistance (MDR) in Acinetobacter baumannii We have shown that modulation of expression of the structural genes for the efflux systems AdeABC and AdeIJK confers MDR and results in numerous alterations of membrane-associated cellular functions, in particular biofilm formation. However, the contribution of these RND pumps to cell fitness and virulence has not yet been studied...
2016: MBio
Zachary Aron, Timothy J Opperman
The rise of multidrug resistant (MDR) Gram-negative pathogens complicates our ability to treat bacterial infections with antibiotics. MDR efflux pumps play a major role in the acquisition and expression of the MDR phenotype. The major MDR efflux pumps in Gram-negative pathogens are the resistance-nodulation-division (RND) superfamily pumps. Efflux pump inhibitors (EPIs) that target RND superfamily pumps could play an important role in the clinic as an adjunctive therapy to increase antibiotic efficacy, decrease resistance, and attenuate virulence in Gram-negative pathogens...
May 24, 2016: Current Opinion in Microbiology
Rodrigo Sandoval, Cristian Oliver, Sharin Valdivia, Karla Valenzuela, Ronie E Haro, Patricio Sánchez, Víctor H Olavarría, Paulina Valenzuela, Rubén Avendaño-Herrera, Alex Romero, Juan G Cárcamo, Jaime E Figueroa, Alejandro J Yáñez
Piscirickettsia salmonis is a fastidious intracellular pathogen responsible for high mortality rates in farmed salmonids, with serious economic consequences for the Chilean aquaculture industry. Oxytetracycline and florfenicol are the most frequently used antibiotics against P. salmonis, but routine use could contribute to drug resistance. This study identified differentiated florfenicol susceptibilities in two P. salmonis strains, LF-89 and AUSTRAL-005. The less susceptible isolate, AUSTRAL-005, also showed a high ethidium bromide efflux rate, indicating a higher activity of general efflux pump genes than LF-89...
June 2016: FEMS Microbiology Letters
Joel W J Refos, Birgit I Witte, Cees J T de Goede, Remco de Bree
BACKGROUND: Donor site morbidity of pectoralis major pedicled flap (PMPF) is scarcely studied. METHODS: A cross-sectional study on patients who underwent reconstructive surgery with a PMPF at least 6 months before was performed. Patients with a similar type neck dissection on both sides and PMPF on one side (n = 9) were assigned to group 1; patients with neck dissection and PMPF (n = 26) were assigned to group 2; and neck dissection only (n = 47) were assigned to group 3...
August 2016: Head & Neck
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"