1.
Antibacterial activity of medicinal plants against ESKAPE: An update.
Bhatia, P, Sharma, A, George, AJ, Anvitha, D, Kumar, P, Dwivedi, VP, Chandra, NS
Heliyon. 2021;(2):e06310
Abstract
Antibiotic resistance has emerged as a threat to global health, food security, and development today. Antibiotic resistance can occur naturally but mainly due to misuse or overuse of antibiotics, which results in recalcitrant infections and Antimicrobial Resistance (AMR) among bacterial pathogens. These mainly include the MDR strains (multi-drug resistant) of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). These bacterial pathogens have the potential to "escape" antibiotics and other traditional therapies. These bacterial pathogens are responsible for the major cases of Hospital-Acquired Infections (HAI) globally. ESKAPE Pathogens have been placed in the list of 12 bacteria by World Health Organisation (WHO), against which development of new antibiotics is vital. It not only results in prolonged hospital stays but also higher medical costs and higher mortality. Therefore, new antimicrobials need to be developed to battle the rapidly evolving pathogens. Plants are known to synthesize an array of secondary metabolites referred as phytochemicals that have disease prevention properties. Potential efficacy and minimum to no side effects are the key advantages of plant-derived products, making them suitable choices for medical treatments. Hence, this review attempts to highlight and discuss the application of plant-derived compounds and extracts against ESKAPE Pathogens.
2.
Understanding specificity and sensitivity of T-cell recognition.
George, AJ, Stark, J, Chan, C
Trends in immunology. 2005;(12):653-9
Abstract
The response of T cells to antigen shows an amazing degree of both sensitivity and specificity, with a cell responding to 1-10 peptide-MHC complexes and being sensitive to single amino acid substitutions. Kinetic proofreading or feedback pathways achieve specificity at the level of the receptor, whereas serial engagement of receptors by ligand molecules enhances sensitivity. Crosstalk between receptors, integration of signals and/or tuning of responses is important at the level of the cell. Induction of anergic or regulatory cells by suboptimal stimuli prevents cell activation by multiple encounters with weak ligands. Thus, for optimal sensitivity and specificity, it is necessary to have mechanisms that operate at the level of the receptor, the cell and finally, the population of responding cells.
3.
Central nervous system stimulants.
George, AJ
Bailliere's best practice & research. Clinical endocrinology & metabolism. 2000;(1):79-88
Abstract
Three major types of CNS stimulant are currently abused in sport: amphetamine, cocaine and caffeine. Each drug type has its own characteristic mechanism of action on CNS neurones and their associated receptors and nerve terminals. Amphetamine is widely abused in sports requiring intense anaerobic exercise where it prolongs the tolerance to anaerobic metabolism. It is addictive, and chronic abuse causes marked behavioural change and sometimes psychosis. Major sports abusing amphetamine are cycling, American football, ice-hockey and baseball. Cocaine increases tolerance to intense exercise, yet most of its chronic effects on energy metabolism are negative. Its greatest effects seem to be as a central stimulant and the enhancement of short-term anaerobic exercise. It is highly addictive and can cause cerebral and cardiovascular fatalities. Caffeine enhances fatty acid metabolism leading to glucose conservation, which appears to benefit long-distance endurance events such as skiing. Caffeine is also addictive, and chronic abuse can lead to cardiac damage. Social abuse of each of the three drugs is often difficult to distinguish from their abuse in sport.