Identifying the Molecular Fingerprint of Beta-Lactams via Raman/SERS Spectroscopy Using Unconventional Nanoparticles for Antimicrobial Stewardship.

Beta-lactam antibiotics, derived from penicillin, are the most used class of antimicrobials used for treating bacterial infections. Over the years, microorganisms have developed resistance mechanisms capable of preventing the effect of these drugs. This condition has been a significant public health concern for the 21st century, especially after predictions that antimicrobial resistance could lead to 10 million deaths annually by 2050.

Laser Ablated Albumin Functionalized Spherical Gold Nanoparticles Indicated for Stem Cell Tracking.

Cell tracking in cell-based therapy applications helps distinguish cell participation among paracrine effect, neovascularization, and matrix deposition. This preliminary study examined the cellular uptake of gold nanoparticles (AuNPs), observing cytotoxicity and uptake of different sizes and AuNPs concentrations in Adipose-derived stromal cells (ASCs). ASCs were incubated for 24 h with Laser ablated Albumin functionalized spherical AuNPs (LA-AuNPs), with average sizes of 2 nm and 53 nm in diameter, in four concentrations, 127 µM, 84 µM, 42 µM, and 23 µM.

Bismuth-based nanoparticles impair adipogenic differentiation of human adipose-derived mesenchymal stem cells.

Bismuth-based nanoparticles (BiNPs) have attracted attention for their potential biomedical applications. However, there is a lack of information concerning their interaction with biological systems. In this study, it was investigated the effect of physically synthesized BiNPs to human adipose-derived stem cells (ADSCs).

Polysaccharide-based substrate for surface-enhanced Raman spectroscopy.

Surface-enhanced Raman spectroscopy (SERS) became a useful analytical technique with the development of appropriate metallic substrates. The need for SERS substrates that immobilize metallic nanoparticles prompted this work to search for an appropriate material. This work presents the preparation, characterization and application of a SERS substrate for crystal violet (CV) detection, as the probe molecule.

Cytotoxicity of bismuth nanoparticles in the murine macrophage cell line RAW 264.7.

A promising use of bismuth nanoparticles (BiNPs) for different biomedical applications leads to a search for the elucidation of their toxicity mechanisms, since toxicity studies are still at early stage. In the current study, cytotoxic effects of BiNPs produced by laser ablation in solution (LASiS) was investigated in the murine macrophage line RAW 264.7.

Malignancy and tumorigenicity of melanoma B16 cells are not affected by silver and gold nanoparticles.

Gold (AuNP) and silver (AgNP) nanoparticles have been incorporated into many therapeutic and diagnostic applications. However, previous studies revealed toxic properties as well as the hormesis phenomenon of many nanoparticles in different biological models. To evaluate the effects of low concentrations of AuNP and AgNP on murine melanoma cells B16F1 and B16F10 and relate them with phenotype changes, cells were exposed for 24 and 48 h.

Dose-dependent cytotoxicity of bismuth nanoparticles produced by LASiS in a reference mammalian cell line BALB/c 3T3.

Nanoparticles (NPs) have emerged as new potential tools for many applications in previous years. Among all types of NPs, bismuth NPs (BiNPs) have a very low cost and potential for many applications, ranging from medicine to industry. Although the toxic effects of bismuth have been studied, little is known about its toxicity at the nanoscale level.

Anti-hMC2RL1 Functionalized Gold Nanoparticles for Adrenocortical Tumor Cells Targeting and Imaging.

The low rate of cure of adrenocortical carcinomas (ACC) in children and adults is related to germ line TP53 mutation, late diagnosis, incomplete surgical resection, and lack of an efficient adjunctive therapy. To provide a new approach for the improvement of ACC diagnosis and therapy, the present study aimed to explicitly target ACC cells using gold nanoparticle (AuNP) probes bound to specific antibodies. Immunohistochemistry of ACC and positive and negative control tissue micro-sections under light microscopy was used to test a purified polyclonal antibody raised against the 80–93, outer loop 1 position of the human melanocortin receptor 2 (hMC2R).

Toxicological interactions of silver nanoparticles and non-essential metals in human hepatocarcinoma cell line.

Toxicological interaction represents a challenge to toxicology, particularly for novel contaminants. There are no data whether silver nanoparticles (AgNPs), present in a wide variety of products, can interact and modulate the toxicity of ubiquitous contaminants, such as nonessential metals. In the current study, we investigated the toxicological interactions of AgNP (size=1-2nm; zeta potential=-23mV), cadmium and mercury in human hepatoma HepG2 cells.

Comparison of the Efficiency of Rose Bengal and Methylene Blue as Photosensitizers in Photodynamic Therapy Techniques for Enterococcus faecalis Inactivation.

Objective And Background: The aim of this in vitro study was to compare the efficiency of a photodynamic therapy (PDT) technique employing rose bengal (RB) and methylene blue (MB) as photosensitizers (PSs) to reduce the viability of Enterococcus faecalis, a well-known pathogen found in root canal systems. Currently, in several clinical applications, including in the field of endodontics, MB is employed in association with a red laser source for the photoinactivation of pathogenic bacteria.

Methods: In this study, MB was used at 0.

The photocycle and proton translocation pathway in a cyanobacterial ion-pumping rhodopsin.

The genome of thylakoidless cyanobacterium Gloeobacter violaceus encodes a fast-cycling rhodopsin capable of light-driven proton transport. We characterize the dark state, the photocycle, and the proton translocation pathway of GR spectroscopically. The dark state of GR contains predominantly all-trans-retinal and, similar to proteorhodopsin, does not show the light/dark adaptation.

Cytoplasmic shuttling of protons in anabaena sensory rhodopsin: implications for signaling mechanism.

It was found recently that Anabaena sensory rhodopsin (ASR), which possibly serves as a photoreceptor for chromatic adaptation, interacts with a soluble cytoplasmic transducer. The X-ray structure of the transducer-free protein revealed an extensive hydrogen-bonded network of amino acid residues and water molecules in the cytoplasmic half of ASR, in high contrast to its haloarchaeal counterparts. Using time-resolved spectroscopy of the wild-type and mutant ASR in the visible and infrared ranges, we tried to determine whether this hydrogen-bonded network is used to translocate protons and whether those proton transfers are important for interaction with the transducer.

Leptosphaeria rhodopsin: bacteriorhodopsin-like proton pump from a eukaryote.

Bacteriorhodopsin-like proteins provide archaea and eubacteria with a unique bioenergetic pathway comprising light-driven transmembrane proton translocation by a single retinal-binding protein. Recently, homologous proteins were found to perform photosensory functions in lower eukaryotes, but no active ion transport by eukaryotic rhodopsins was detected. By demonstrating light-driven proton pumping in a fungal rhodopsin from Leptosphaeria maculans, we present a case of a retinal-based proton transporter from a eukaryote.

FTIR spectroscopy of the K photointermediate of Neurospora rhodopsin: structural changes of the retinal, protein, and water molecules after photoisomerization.

Neurospora rhodopsin (NR, also known as NOP-1) is the first rhodopsin of the haloarchaeal type found in eucaryotes. NR demonstrates a very high degree of conservation of the amino acids that constitute the proton-conducting pathway in bacteriorhodopsin (BR), a light-driven proton pump of archaea. Nevertheless, NR does not appear to pump protons, suggesting the absence of the reprotonation switch that is necessary for the active transport.