Cholesterol Functionalized Nanoparticles Are Effective against Helicobacter pylori, the Gastric Bug: A Proof-of-Concept Study.

Helicobacter pylori chronic infection is the highest risk factor for the development of gastric cancer, being this Gram-negative bacterium classified as carcinogenic. The mounting resistance of H. pylori to antibiotics calls for innovative therapeutic strategies.

Novel microbial synthesis of titania nanoparticles using probiotic Bacillus coagulans and its role in enhancing the microhardness of glass ionomer restorative materials.

Dental caries is a commonly occurring non-communicable disease throughout the world that might compromise the quality of any individual's life. Glass ionomer cements (GIC) are the most acceptable restorative materials due to their ease of manipulation, minimal tooth loss and least invasive strategy; however, they lack mechanical stability that has become a point of concern. Nanoparticles (NPs) are an outstanding option for modifying and enhancing the properties of dental materials.

Recent Advances in the Development of Antibiotics-Coated Gold Nanoparticles to Combat Antimicrobial Resistance.

Antimicrobial resistance (AMR) has become an alarming threat to the successful treatment of rapidly growing bacterial infections due to the abuse and misuse of antibiotics. Traditional antibiotics bear many limitations, including restricted bioavailability, inadequate penetration and the emergence of antimicrobial-resistant microorganisms. Recent advances in nanotechnology for the introduction of nanoparticles with fascinating physicochemical characteristics have been predicted as an innovative means of defence against antimicrobial-resistant diseases.

Advances in the design of amino acid and peptide synthesized gold nanoparticles for their applications.

The field of therapeutics and diagnostics is advanced by nanotechnology-based approaches including the spatial-temporal release of drugs, targeted delivery, enhanced accumulation of drugs, immunomodulation, antimicrobial action, and high-resolution bioimaging, sensors and detection. Various compositions of nanoparticles (NPs) have been developed for biomedical applications; however, gold NPs (Au NPs) have attracted tremendous attention due to their biocompatibility, easy surface functionalization and quantification. Amino acids and peptides have natural biological activities as such, their activities enhance several folds in combination with NPs.

May carriers at nanoscale improve the Endodontic's future?

Nanocarriers (NCs) are dynamic nanovehicles used to transport bioactive derivatives like therapeutical formulations, drugs and/or dyes. The current review assists in understanding the mechanism of action of several recent developed NCs with antimicrobial purposes. Here, nine NCs varieties are portrayed with focus on nineteen approaches that are fulfil described based on outcomes obtained from in vitro antimicrobial assays.

Acidic sophorolipid and antimicrobial peptide based formulation as antimicrobial and antibiofilm agents.

Antimicrobial peptides (AMPs) are considered promising candidates to treat various infections in soft tissues and skin. However, no effective treatment based on AMPs has been reached to clinics due to their instability in serum and wounds. Biosurfactants such as acidic sophorolipids (ASLs) of very high concentrations (equal or above 5 mg/mL) have been demonstrated to be antimicrobial agents, however these concentrations might induce cytotoxic effects to human cells.

Antimicrobial Peptide-Tether Dressing Able to Enhance Wound Healing by Tissue Contact.

No effective therapeutic dressings are currently available in the market that can prevent bacterial infection and simultaneously promote skin regeneration in diabetic patients. The lack of re-epithelization, prevalence of inflammation, and high risk of infection are hallmarks of non-healing wounds. Here, we have evaluated the antimicrobial and pro-regenerative effect of a relatively non-leaching LL37 peptide immobilized in polyurethane (PU)-based wound dressings (PU-adhesive-LL37 dressing).

Antimicrobial peptide-based materials: opportunities and challenges.

The multifunctional properties of antimicrobial peptides (AMPs) make them attractive candidates for the treatment of various diseases. AMPs are considered as alternatives to antibiotics due to the increasing number of multidrug-resistant (MDR) bacteria. However, bare AMPs have limited therapeutic potentials due to a low residence time in the blood circulatory system and susceptibility to proteases and an alkaline wound environment.

Antimicrobial and pro-angiogenic properties of soluble and nanoparticle-immobilized LL37 peptides.

Antimicrobial peptides (AMPs), such as LL37 peptides, may be immobilized on the surface of medical devices to render them with antimicrobial and angiogenic properties. However, little is known about LL37 properties after immobilization. Here, we have studied the antimicrobial and pro-angiogenic activity of soluble and immobilized LL37 peptides (conjugated to gold nanoparticles).

Induced pluripotent stem cell-derived vascular networks to screen nano-bio interactions.

The vascular bioactivity/safety of nanomaterials is typically evaluated by animal testing, which is of low throughput and does not account for biological differences between animals and humans such as ageing, metabolism and disease profiles. The development of personalized human in vitro platforms to evaluate the interaction of nanomaterials with the vascular system would be important for both therapeutic and regenerative medicine. A library of 30 nanoparticle (NP) formulations, in use in imaging, antimicrobial and pharmaceutical applications, was evaluated in a reporter zebrafish model of vasculogenesis and then tested in personalized humanized models composed of human-induced pluripotent stem cell (hiPSC)-derived endothelial cells (ECs) with "young" and "aged" phenotypes in 3 vascular network formats: 2D (in polystyrene dish), 3D (in Matrigel) and in a blood vessel on a chip.

Biomedical applications of the peptide decorated gold nanoparticles.

Currently, peptide-nanoparticle (NP) conjugates have been demonstrated to be efficient and powerful tools for the treatment and the diagnosis of various diseases as well as in the bioimaging application. Several bioconjugation strategies have been adopted to formulate the peptide-NP conjugates. In this review, we discuss the exciting applications of peptide-gold (Au) NP conjugates in the area of drug delivery, targeting, cancer therapy, brain diseases, vaccines, immune modulation, biosensor, colorimetric detection of heavy metals, and bio-labeling and models.

A light-triggerable formulation to control the stability of pro-angiogenic transcription factor hypoxia inducible factor-1α (HIF-1α).

The control of vascular remodeling mediated by transcription factor HIF-1α is critical in the treatment of several diseases including cancer, retinopathies, chronic wounds, and ischemic heart disease, among others. Gene silencing using a small interfering RNA (siRNA) is a promising therapeutic strategy to regulate HIF-1α; however, the delivery systems developed so far have limited endothelial targeting and efficiency. Herein, we have synthesized a light-triggerable polymeric nanoparticle (NP) library composed of 110 formulations which showed variable morphology, charge and disassembly rates after UV exposure.

Atomistic-Level Investigation of a LL37-Conjugated Gold Nanoparticle By Well-Tempered Metadynamics.

LL37 is a cathelicidin-derived antimicrobial peptide (AMP) with a broad spectrum of antimicrobial activity and wound-healing potential. The enhancement of these characteristics was recently demonstrated for a cysteine (CYS)-modified cathelicidin-derived LL37-SH conjugated with gold nanoparticles (AuNPs). Considering the potential of this peptide, we hereby report a computational study in which well-tempered metadynamics was applied to unveil the interaction of LL37-SH and LL37 with a AuNP with atomistic detail.

A nanoformulation for the preferential accumulation in adult neurogenic niches.

Stimulation of adult neurogenesis by targeting the endogenous neural stem cells (NSCs), located in hippocampus and subventricular zone (SVZ), with nanoformulations has been proposed for brain repair in cases of neurodegenerative diseases. Unfortunately, it is relatively unknown the nanoformulation properties to facilitate their accumulation in the neurogenic niches after intravenous injection. Here, we have screened different gold-based formulations having variable morphology, surface chemistry and responsiveness to light for their capacity to cross the blood brain barrier (BBB) and accumulate preferentially in the neurogenic niches.

MicroRNA-124-loaded nanoparticles increase survival and neuronal differentiation of neural stem cells in vitro but do not contribute to stroke outcome in vivo.

There is a high quest for novel therapeutic strategies to enhance recovery after stroke. MicroRNA-124 (miR-124) has been described as neuroprotective and anti-inflammatory molecule. Moreover, miR-124 is a well described enhancer of adult neurogenesis that could offer potentially beneficial effects.

Antimicrobial peptide-gold nanoscale therapeutic formulation with high skin regenerative potential.

Chronic skin wounds affect ≈3% of persons aged >60years (Davies et al., 2007) [1]. These wounds are typically difficult to heal by conventional therapies and in many cases they get infected making even harder the regeneration process.

Findings on the interaction of the antimicrobial peptide cecropin-melittin with a gold surface from molecular dynamics studies.

The immobilization of gold nanoparticles (AuNPs) with antimicrobial peptides (AMPs) is a new and promising way to enhance both the activity and targeting capabilities of AMPs. However, a full understanding of the adsorption process underlying these materials is still lacking. Cecropin-melittin is a peptide with a broad antimicrobial activity while displaying low hemolytic properties, whose conjugation with AuNPs has not been studied before.

High Antimicrobial Activity and Low Human Cell Cytotoxicity of Core-Shell Magnetic Nanoparticles Functionalized with an Antimicrobial Peptide.

Superparamagnetic iron oxide nanoparticles (SPIONs) functionalized with antimicrobial agents are promising infection-targeted therapeutic platforms when coupled with external magnetic stimuli. These antimicrobial nanoparticles (NPs) may offer advantages in fighting intracellular pathogens as well as biomaterial-associated infections. This requires the development of NPs with high antimicrobial activity without interfering with the biology of mammalian cells.

One-step synthesis of high-density peptide-conjugated gold nanoparticles with antimicrobial efficacy in a systemic infection model.

The increase in antibiotic drug resistance and the low number of new antibacterial drugs approved in the last few decades requires the development of new antimicrobial strategies. Antimicrobial peptides (AMPs) are very promising molecules to fight microbial infection since they kill quickly bacteria and, in some cases, target bacterial membrane. Although some AMPs may be stable against proteolytic degradation by chemical modification, in general, low AMP activity and stability in the presence of serum and proteolytic enzymes as well as their cytotoxicity have impaired their clinical translation.

High-density antimicrobial peptide coating with broad activity and low cytotoxicity against human cells.

Unlabelled: Medical device-associated infections are a multi-billion dollar burden for the worldwide healthcare systems. The modification of medical devices with non-leaching coatings capable of killing microorganisms on contact is one of the strategies being investigated to prevent microorganism colonization. Here we developed a robust antimicrobial coating based on the chemical immobilization of the antimicrobial peptide (AMP), cecropin-melittin (CM), on gold nanoparticles coated surfaces.

Facile fabrication of uniform silica films with tunable physical properties using silicatein protein from sponges.

We report an elegant and simple method to fabricate uniform silica films with controlled thickness, roughness, and hydrophilicity using nanogram quantities of silicatein, a protein involved in silica synthesis in sponges. The formation of uniform silica films was achieved by immobilization of silicatein on gold-coated surfaces that had been functionalized with amines. Specifically, the amines, cystamine and cysteamine having disulfide and thiol groups, respectively, were bound to surfaces and treated with a cross-linking agent, glutardialdehyde (GDA) before protein immobilization.

Role of halide ions and temperature on the morphology of biologically synthesized gold nanotriangles.

In this paper, we demonstrate the effect of halide ions on the formation of biogenically prepared gold nanotriangles using the leaf extract of lemongrass (Cymbopogon flexuosus) plant. We have also studied the effect of halide ions on the morphology of biogenic nanotriangles. It has been shown that iodide ions have a greater propensity to transform flat gold nanotriangles into circular disk-like structures as compared to other halide ions.

Biological synthesis of triangular gold nanoprisms.

The optoelectronic and physicochemical properties of nanoscale matter are a strong function of particle size. Nanoparticle shape also contributes significantly to modulating their electronic properties. Several shapes ranging from rods to wires to plates to teardrop structures may be obtained by chemical methods; triangular nanoparticles have been synthesized by using a seeded growth process.

Rapid synthesis of Au, Ag, and bimetallic Au core-Ag shell nanoparticles using Neem (Azadirachta indica) leaf broth.

We report on the use of Neem (Azadirachta indica) leaf broth in the extracellular synthesis of pure metallic silver and gold nanoparticles and bimetallic Au/Ag nanoparticles. On treatment of aqueous solutions of silver nitrate and chloroauric acid with Neem leaf extract, the rapid formation of stable silver and gold nanoparticles at high concentrations is observed to occur. The silver and gold nanoparticles are polydisperse, with a large percentage of gold particles exhibiting an interesting flat, platelike morphology.