Mechanisms of Antimicrobial Resistance in Pseudomonas aeruginosa and a Multi-Pronged Approach to Combat its Infection in Veterinary Science and Public Health: A Review

Pseudomonas aeruginosa is one of the most important nosocomial pathogens associated with a variety of medical and veterinary infections and therefore, it presents a major public health threat. Different classes of antibiotics are being used to treat its infections which are increasing selective pressure to multi-drug resistance development. Resistance to antibiotics in P. aeruginosa is due to many of the common and unique mechanisms which include: reducing membrane permeability, modification or inactivation of antibiotics, alteration of enzymes, modification of target sites and over-expression of efflux systems. Over or under expression of the genes of porin channels and components of efflux systems play a major role in the resistance mechanisms of P. aeruginosa. To overcome the problem of the emergence of antibiotic resistance, many new strategies are being employed to control infections caused by P. aeruginosa. These include the use of herbs/medicinal plants and phage therapy. With the advent of modern technology, the molecular mechanisms of these alternative therapies are being elucidated and may be used in future to treat P. aeruginosa infections in humans and veterinary clinics. This review thus highlights the mechanisms of antibiotic resistance of P. aeruginosa against the commonly used antimicrobials and also some alternative strategies to control P. aeruginosa infection. © 2021 Friends Science Publishers

Colloidal dispersion gels for in-depth permeability modification

In this study, we describe the synthesis, characterization and evaluation of colloidal dispersion gels (CDGs) to be used as in-situ fluid diversion. The chemical stability of CDGs was improved by modifying the polymer mixture. The CDGs were synthesized by free radical crosslinking polymerization using 2-acrylamido-2-methylpropane sulfonic acid (AMPS), Acrylic acid (AAc), partially hydrolyzed polyacrylamide (HPAM) and chromium triacetate crosslinker. The effect of crosslinker/polymer concentration, salinity, gelation time, rheological behavior, particle size distribution of CDGs, also their thermo-chemical stabilities and resistance/residual resistance factor (RRF) were investigated.

Effective Mechanisms to Relate Initial Rock Permeability to Outcome of Relative Permeability Modification

Excessive water production is becoming common in many gas reservoirs. Polymers have been used as relative permeability modifiers (RPM) to selectively reduce water production with minimum effect on the hydrocarbon phase. This manuscript reports the results of an experimental study where we examined the effect of initial rock permeability on the outcome of an RPM treatment for a gas/water system. The results show that in high-permeability rocks, the treatment may have no significant effect on either the water and gas relative permeabilities. In a moderate-permeability case, the treatment was found to reduce water relative permeability significantly but improve gas relative permeability, while in low-permeability rocks, it resulted in greater reduction in gas relative permeability than that of water. This research reveals that, in an RPM treatment, more important than thickness of the adsorbed polymer layer ( e ) is the ratio of this thickness on rock pore radius ( e r ).

Polymer Gelled Technology to Improve Sweep Efficiency in Enhanced Oil Recovery: A Literature Review

This article is an overview of the use of polymer gelled technology to improve sweep efficiency in enhanced oil recovery. Recent progress use polymer types, Polyacrylamide and polysaccharide to be applied in enhanced oil recovery (EOR). A lot of researchers concluded that polymer gel stability must be maintained to ensure excellent performance in sweep efficiency. The application of polymer gels in permeability modification to improve volumetric sweep efficiency of fluid injection processes showed fruitful efforts as it can be a potential candidate to enhance oil recovery as compared to other technologies.