Based on the recent reports of World Health Organization, increased antibiotic resistance prevalence among bacteria represents the greatest challenge to human health. In addition, the poor solubility, stability, and side effects that lead to inefficiency of the current antibacterial therapy prompted the researchers to explore new innovative strategies to overcome such resilient microbes. Hence, novel antibiotic delivery systems are in high demand. Nanotechnology has attracted considerable interest due to their favored physicochemical properties, drug targeting efficiency, enhanced uptake, and biodistribution. The present review focuses on the recent applications of organic (liposomes, lipid-based nanoparticles, polymeric micelles, and polymeric nanoparticles), and inorganic (silver, silica, magnetic, zinc oxide (ZnO), cobalt, selenium, and cadmium) nanosystems in the domain of antibacterial delivery. We provide a concise description of the characteristics of each system that render it suitable as an antibacterial delivery agent. We also highlight the recent promising innovations used to overcome antibacterial resistance, including the use of lipid polymer nanoparticles, nonlamellar liquid crystalline nanoparticles, anti-microbial oligonucleotides, smart responsive materials, cationic peptides, and natural compounds. We further discuss the applications of antimicrobial photodynamic therapy, combination drug therapy, nano antibiotic strategy, and phage therapy, and their impact on evading antibacterial resistance. Finally, we report on the formulations that made their way towards clinical application.

Aim To develop the topical gel containing transferosomal lidocaine as alternative to painful local anesthetic injection. Materials and methods The transfersomes were prepared by film hydration technique using soybean phosphatidylcholine and cholesterol. The prepared transfersomes were evaluated for the morphology, drug loading, %EE, particle size and in vitro release. The transferosomal gel of lidocaine was prepared using HPMC k15 as gelling agent and propylene glycol, dimethyl sulfoxide (DMSO), and polyamidoamine dendrimer third generation (PAMAM G3) solutions were used as permeation enhancer. The formulated gels were evaluated for pH, viscosity, drug content and ex-vivo permeation of the gel. The analgesic effect of the formulation was tested using tail flick test. Results The transfersomes showed that transfersomes (F4) had the highest entrapment efficiency (%EE) approaching 79.87±2.35, low particle size 179.5 nm, and zeta potential of −43.5±4.74 mV. According to the rat tail flick test, the AUC 0–90 minutes of the control formulation (lidocaine solution, A) was 352.32±5.87 seconds minutes. While the maximum AUC 0–90 minutes value was found to be 570.5±6.81 seconds minutes for gel formulation (F) containing transfersomal lidocaine with PAMAM G3 dendrimer as permeation enhancer. In this case, the local anesthetic efficacy was increased by 1.62-folds as compared to control formulation. Conclusion From the present study, it can be concluded that the topical gel loaded with transfersomal lidocaine shows enhanced skin permeation effect along with increase in local anesthetic action of lidocaine.

Staphylococcus haemolyticus ( S. haemolyticus ) is one of the Coagulase-negative staphylococci (CoNS) that inhabits the skin as a commensal. It is increasingly implicated in opportunistic infections, including diabetic foot ulcer (DFU) infections. In contrast to the abundance of information available for S. aureus and S. epidermidis , little is known about the pathogenicity of S. haemolyticus , despite the increased prevalence of this pathogen in hospitalized patients. We described, for the first time, the pathogenesis of different clinical isolates of S. haemolyticus isolated from DFU on primary human skin fibroblast (PHSF) cells. Virulence-related genes were investigated, adhesion and invasion assays were carried out using Giemsa stain, transmission electron microscopy (TEM), MTT and flowcytometry assays. Our results showed that most S. haemolyticus carried different sets of virulence-related genes. S. haemolyticus adhered to the PHSF cells to variable degrees. TEM showed that the bacteria were engulfed in a zipper-like mechanism into a vacuole inside the cell. Bacterial internalization was confirmed using flowcytometry and achieved high intracellular levels. PHSF cells infected with S.haemolyticus suffered from amarked decrease in viability and increased apoptosis when treated with whole bacterial suspensions or cell-free supernatants but not with heat-treated cells. After co-culture with PBMCs, S. haemolyticus induced high levels of pro-inflammatory cytokines. This study highlights the significant development of S. haemolyticus , which was previously considered a contaminant when detected in cultures of clinical samples. Their high ability to adhere, invade and kill the PHSF cells illustrate the severe damage associated with DFU infections. Abbreviations CoNS, coagulase-negative staphylococci; DFU, diabetic foot ulcer; DM, diabetes mellitus; DMEM, Dulbecco’s Modified Eagle Medium; MTT, 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide; PBMCs,peripheral blood mononuclear cells; PHSF, primary human skin fibroblast; CFU, colony-forming unit.

Even though chickpea {Cicer arietinum L.) is well adapted to growing on stored soil moisture in drought-prone environments, drought is a major yield reducer in most chickpea-growing regions. Little progress has been made in breeding for improved performance under drought stress for want of a reliable and repeatable method of screening for drought resistance. Therefore, a study was initiated in 1990 to develop a screening technique and a rating scale to evaluate germplasm for drought resistance. A spring date-of-planting experiment was conducted during spring from 1990 to 1992 at Tel Hayda (northern Syria) to see if the expression of genotypic differences in drought resistance should be accentuated. Simultaneously, a rating scale was developed. Using the screening technique and rating scale, over 4000 germplasm lines were evaluated from 1992 to 1995. The resulting screening techniqtie involves delayed sowing by 3 weeks during spring at a relatively dry site (long-term average annual rainfall of 328 mm), preliminary evaltiation of materials on a rating scale of i-9 to discard susceptible lines, and final evaluation of promising lines under stress (drought) and non-stress (supplemental irrigation) conditions, selecting drought-resistant lines which perform well under both conditions. In the 1-9 rating scale that was developed: 1 = no yield reduction as compared to a non-stress control and 9 = al! plants dry without producing any seed. Using this technique, 19 lines out of 4165 lines screened were identified as drought resistant, producing over 1 t ha"' seed yield under drought conditions while being able to yield over 2 t b"' under nonstress conditions. Resistant lines are being used by national programs in the Mediterranean region and by ICARDA for developing drought-and disease-resistant. high-yielding cultivars.