New antibiotic development: the need versus the costs

Evaluating Antimicrobial Activity and Wound Healing Effect of Rod-Shaped Nanoparticles

Presently, the nanotechnology approach has gained a great concern in the media of drug delivery. Gold nanoparticles (Au-NPs) specially having a non-spherical structure, such as gold nanorods (GNR), are attracting much interest as antibacterial agent and many other medical fields. The aim of the current investigation was to characterize Au-NPs and investigate their antimicrobial and wound healing efficacy in diabetic animals. Material and methods: Au-NPs were characterized using a UV-Vis spectrophotometer, estimating their particle size, polydispersity (PDI), and assessing their morphological characters. Further, Au-NPs were estimated for their antibacterial and antifungal behavior. Ultimately, in vivo activity of Au-NPs was evaluated against excision wound healing in STZ-induced diabetic animals. Results: Au-NPs were found to show maximum absorption at 520 nm. They exhibited a particle size of 82.57 nm with a PDI value of 0.323. Additionally, they exhibited good antimicrobial activity against different bacterial strains. Topical application of Au-NPs caused a significantly increased percentage of wound area reduction, lesser time needed for epithelialization, and augmented hydroxyproline, collagen, and hexosamine levels demonstrating enhanced healing processes. Furthermore, Au-NPs displayed a significant intensification in angiogenesis-related factors (HIF-1α, TGF-β1, and VEGF), and antioxidant enzymes activities (CAT, SOD, GPx) as well as mitigated inflammatory mediators IL-6, IL-1β, TNF-α, and NF-κB) and lipid peroxidation (MDA). Conclusion: Au-NPs exhibited proper particle size, and rod-shaped particles, with efficient antimicrobial behavior against different bacterial strains. Furthermore, Au-NPs demonstrated a promising wound healing activity in STZ-induced diabetic animals.

Flavonoid-Decorated Nano-gold for Antimicrobial Therapy Against Gram-negative Bacteria Escherichia coli

Nano-gold (Aunps) have emerged as promising options that exhibit unique features discrete from traditional materials suited for biomedical applications. Aunps were synthesized using flavonoid quercetin (Q) as reducing agent, and resultant nanoparticles were further conjugated with the flavonoid. The resultant nano-system was expected to perform a dual role as antibacterial and as antioxidant agent. Nano-gold surface plasmon peaks were recorded at 560 nm with size around 62 nm and having slim distribution pattern. Spherical particle with smooth surface was observed under TEM and AFM studies. TEM micrographs confirmed a homogeneous particle population of size around 30 nm. Quercetin association to nano-gold was corroborated through FTIR and EDAX analysis. Antioxidant nature of nano-gold prevented rapid oxidation of brilliant cresyl blue dye, in presence of sodium hypochlorite. Antimicrobial action of QuAunp was tested against Gram-negative bacteria Escherichia coli. Nano-gold designed produced a minimum inhibitory concentration of 7.6 μg/ml and minimum bactericidal concentration 10.5 μg/ml against E. coli. Further TEM analysis and membrane permeability studies revealed the impact of QuAunps on bacterial membrane leading to cell damage.

Developing a hybrid antimicrobial resistance surveillance system in India: Needs & challenges

Growing resistance to antimicrobials has become one of the most important problems of the 21^st century. The development of new antibiotics is a time-consuming process involving huge financial resources. An alternate approach is proper utilization of the existing antibiotics through the surveillance of resistance. An important component of surveillance is the informatics tool for collection, management and analysis of antimicrobial resistance susceptibility testing data. Based on the scope, antimicrobial resistance surveillance resistance tools can be broadly classified as collectors and integrators. Individually, both the integrators and collectors have limitations which restrict their use in India. There is a strong requirement to develop a hybrid AMR surveillance tool that captures standardized data from small laboratories and integrates data from multiple sources to present a complete picture of the country. Here we describe a tool i-AMRSS developed by the Indian Council of Medical Research for collection, storage and management of AMR data from collaborating institutes/laboratories and to generate real-time analytics and reports.

[Antibiotic Stewardship 2.0. Individualization of therapy]

Antibiotic resistance is a part of bacterial evolution and therefore unavoidable. In the context of missing novel treatment options, the restrictive use of available antibiotics in order to decelerate the spread of resistance is of high importance. This is the aim of Antibiotic Stewardship (ABS). ABS consists of two sides: a structural one and an individual one. The former deals with the formation of ABS teams, the analysis of antibiotic usage and resistance development, and the implementation of certain measures to improve antibiotic use; the latter is reflected by concrete bedside decisions: How can (broad) spectrum antibiotics be spared without harming the patient? This can be achieved, for example, by de-escalation, limiting duration of treatment, and avoiding nonindicated use. Typical nonindicated uses in both in- and outpatients are viral respiratory tract infections, asymptomatic bacteriuria and nonbacterial exacerbations of chronic obstructive pulmonary disease. Furthermore, respiratory colonization in ventilated patients, ventilator-associated tracheobronchitis, "prolonged" perioperative prophylaxis, and contaminated blood cultures reflect situations where antibiotics should be avoided. In the future, ABS will benefit from accelerated pathogen and resistance detection because early adequate treatment not only lowers the usage of antibiotics but can also improve patient outcome.

N-Heterocyclic molecule-capped gold nanoparticles as effective antibiotics against multi-drug resistant bacteria

We demonstrate that N-heterocyclic molecule-capped gold nanoparticles (Au NPs) have broad-spectrum antibacterial activity. Optimized antibacterial activity can be achieved by using different initial molar ratios (1 : 1 and 10 : 1) of N-heterocyclic prodrugs and the precursor of Au NPs (HAuCl4). This work opens up new avenues for antibiotics based on Au NPs.