Investigation of the Mechanism of Action of AMPs from Amphibians to Identify Bacterial Protein Targets for Therapeutic Applications.

Antimicrobial peptides (AMPs) from amphibians represent a promising source of novel antibacterial agents due to their potent and broad-spectrum antimicrobial activity, which positions them as valid alternatives to conventional antibiotics. This review provides a comprehensive analysis of the mechanisms through which amphibian-derived AMPs exert their effects against bacterial pathogens. We focus on the identification of bacterial protein targets implicated in the action of these peptides and on biological processes altered by the effect of AMPs.

The antimicrobial peptide Temporin-L induces vesicle formation and reduces the virulence in .

The evolution of methicillin-resistant () has required the development of new antimicrobial agents and new approaches to prevent and overcome drug resistance. AntiMicrobial Peptides (AMPs) represent promising alternatives due to their rapid bactericidal activity and their broad-spectrum of action against a wide range of microorganisms. The amphibian Temporins constitute a well-known family of AMPs with high antibacterial properties against both Gram-positive and Gram-negative bacteria.

Nanoscale, surface-confined phase separation by electron beam induced oxidation.

Electron-assisted oxidation of Co-Si-based focused electron beam induced deposition (FEBID) materials is shown to form a 2-4 nm metal oxide surface layer on top of an electrically insulating silicon oxide layer less than 10 nm thick. Differences between thermal and electron-induced oxidation on the resulting microstructure are illustrated.

Gas-Phase Synthesis of Iron Silicide Nanostructures Using a Single-Source Precursor: Comparing Direct-Write Processing and Thermal Conversion.

The investigation of precursor classes for the fabrication of nanostructures is of specific interest for maskless fabrication and direct nanoprinting. In this study, the differences in material composition depending on the employed process are illustrated for focused-ion-beam- and focused-electron-beam-induced deposition (FIBID/FEBID) and compared to the thermal decomposition in chemical vapor deposition (CVD). This article reports on specific differences in the deposit composition and microstructure when the (HSi)Fe(CO) precursor is converted into an inorganic material.

Release of a novel peptide from ferritin nanocages: A new tool for therapeutic applications.

The development of new drug delivery systems for targeted chemotherapy release in cancer cells represents a very promising tool. In this contest, protein-based nanocages have considerable potential as drug delivery devices. Notably, ferritin has emerged as an excellent candidate due to its unique architecture, surface properties and high biocompatibility.

The antimicrobial peptide Esc(1-21)-1c increases susceptibility of to conventional antibiotics by decreasing the expression of the MexAB-OprM efflux pump.

The increase in bacterial strains resistant to conventional antibiotics is an alarming problem for human health and could lead to pandemics in the future. Among bacterial pathogens responsible for a large variety of severe infections there is . Therefore, there is an urgent need for new molecules with antimicrobial activity or that can act as adjuvants of antibiotics already in use.

A Comparative Study of the Inhibitory Action of Berberine Derivatives on the Recombinant Protein FtsZ of .

Medicinal plants belonging to the genus may be considered an interesting source of drugs to counteract the problem of antimicrobial multiresistance. The important properties associated with this genus are mainly due to the presence of berberine, an alkaloid with a benzyltetrahydroisoquinoline structure. Berberine is active against both Gram-negative and Gram-positive bacteria, influencing DNA duplication, RNA transcription, protein synthesis, and the integrity of the cell surface structure.

A new and efficient procedure to load bioactive molecules within the human heavy-chain ferritin nanocage.

For their easy and high-yield recombinant production, their high stability in a wide range of physico-chemical conditions and their characteristic hollow structure, ferritins (Fts) are considered useful scaffolds to encapsulate bioactive molecules. Notably, for the absence of immunogenicity and the selective interaction with tumor cells, the nanocages constituted by the heavy chain of the human variant of ferritin (hHFt) are optimal candidates for the delivery of anti-cancer drugs. hHFt nanocages can be disassembled and reassembled to allow the loading of cargo molecules, however the currently available protocols present some relevant drawbacks.

Sensorineural hearing loss after neonatal meningitis: a single-centre retrospective study.

Babies in intensive care are at higher risk for meningitis and sensorineural hearing loss (SNHL). We reviewed the rate of SNHL among definite cases of bacterial/fungal meningitis in our neonatal intensive care unit over a 16-year period (2006-2021). We identified 16 confirmed meningitis cases among 16 070 admissions: 8 of 10 surviving infants with available diagnostic audiology had normal/satisfactory hearing while 2 of 10 had SNHL.

New trends in methyl salicylate sensing and their implications in agriculture.

Methyl salicylate (MeSal) is an organic compound present in plants during stress events and is therefore a key marker for early plant disease detection. It has usually been detected by conventional methods that require bulky and costly equipment, such as gas chromatography or mass spectrometry. Currently, however, chemical sensors provide an alternative for MeSal monitoring, showing good performance for its determination in the vapour or liquid phase.

The antimicrobial peptide Magainin-2 interacts with BamA impairing folding of membrane proteins.

Antimicrobial peptides (AMPs) are a unique and diverse group of molecules endowed with a broad spectrum of antibiotics properties that are being considered as new alternative therapeutic agents. Most of these peptides are membrane-active molecules, killing bacteria by membrane disruption. However, recently an increasing number of AMPs was shown to enter bacterial cells and target intracellular processes fundamental for bacterial life.

Structural and Functional Characterization of a Novel Recombinant Antimicrobial Peptide from .

Antibiotics are commonly used to treat pathogenic bacteria, but their prolonged use contributes to the development and spread of drug-resistant microorganisms raising the challenge to find new alternative drugs. Antimicrobial peptides (AMPs) are small/medium molecules ranging 10-60 residues synthesized by all living organisms and playing important roles in the defense systems. These features, together with the inability of microorganisms to develop resistance against the majority of AMPs, suggest that these molecules might represent effective alternatives to classical antibiotics.

ZnO Structures with Surface Nanoscale Interfaces Formed by Au, FeO, or CuO Modifier Nanoparticles: Characterization and Gas Sensing Properties.

Zinc oxide rod structures are synthetized and subsequently modified with Au, FeO, or CuO to form nanoscale interfaces at the rod surface. X-ray photoelectron spectroscopy corroborates the presence of Fe in the form of oxide-FeO; Cu in the form of two oxides-CuO and CuO, with the major presence of CuO; and Au in three oxidation states-Au, Au, and Au, with the content of metallic Au being the highest among the other states. These structures are tested towards nitrogen dioxide, ethanol, acetone, carbon monoxide, and toluene, finding a remarkable increase in the response and sensitivity of the Au-modified ZnO films, especially towards nitrogen dioxide and ethanol.

Interaction of Temporin-L Analogues with the FtsZ Protein.

The research of new therapeutic agents to fight bacterial infections has recently focused on the investigation of antimicrobial peptides (AMPs), the most common weapon that all organisms produce to prevent invasion by external pathogens. Among AMPs, the amphibian Temporins constitute a well-known family with high antibacterial properties against Gram-positive and Gram-negative bacteria. In particular, Temporin-L was shown to affect bacterial cell division by inhibiting FtsZ, a tubulin-like protein involved in the crucial step of Z-ring formation at the beginning of the division process.

Attentional salience and the neural substrates of response inhibition in borderline personality disorder.

Background: Impulsivity is a central symptom of borderline personality disorder (BPD) and its neural basis may be instantiated in a frontoparietal network involved in response inhibition. However, research has yet to determine whether neural activation differences in BPD associated with response inhibition are attributed to attentional saliency, which is subserved by a partially overlapping network of brain regions.

Methods: Patients with BPD (n = 45) and 29 healthy controls (HCs; n = 29) underwent functional magnetic resonance imaging while completing a novel go/no-go task with infrequent odd-ball trials to control for attentional saliency.

Characterization of the Proteins Involved in the DNA Repair Mechanism in .

Several alkylating agents that either occur in the environment or are self-produced can cause DNA-damaging injuries in bacterial cells. Therefore, all microorganisms have developed repair systems that are able to counteract DNA alkylation damage. The adaptive response to alkylation stress in consists of the Ada operon, which has been widely described; however, the homologous system in (MTB) has been shown to have a different genetic organization but it is still largely unknown.

Antimicrobial and Antibiofilm Peptides.

The increasing onset of multidrug-resistant bacteria has propelled microbiology research towards antimicrobial peptides as new possible antibiotics from natural sources. Antimicrobial peptides are short peptides endowed with a broad range of activity against both Gram-positive and Gram-negative bacteria and are less prone to trigger resistance. Besides their activity against planktonic bacteria, many antimicrobial peptides also show antibiofilm activity.

A Parts Per Billion (ppb) Sensor for NO with Microwatt (μW) Power Requirements Based on Micro Light Plates.

A film of gas sensitive ZnO nanoparticles has been coupled with a low-power micro light plate (μLP) to achieve a NO-parts-per-billion conductometric gas sensor operating at room temperature. In this μLP configuration, an InGaN-based LED (emitting at 455 nm) is integrated at a few hundred nanometers distance from the sensor material, leading to sensor photoactivation with well controlled, uniform, and high irradiance conditions, and very low electrical power needs. The response curves to different NO concentrations as a function of the irradiance displayed a bell-like shape.

Cerium Oxide-Tungsten Oxide Core-Shell Nanowire-Based Microsensors Sensitive to Acetone.

Gas sensitive cerium oxide-tungsten oxide core-shell nanowires are synthesized and integrated directly into micromachined platforms via aerosol assisted chemical vapor deposition. Tests to various volatile organic compounds (acetone, ethanol, and toluene) involved in early disease diagnosis demonstrate enhanced sensitivity to acetone for the core-shell structures in contrast to the non-modified materials (i.e.

Site-Specific Growth and in Situ Integration of Different Nanowire Material Networks on a Single Chip: Toward a Nanowire-Based Electronic Nose for Gas Detection.

A new method for the site-selective synthesis of nanowires has been developed to enable material growth with defined morphology and, at the same time, different composition on the same chip surface. The chemical vapor deposition approach for the growth of these nanowire-based resistive devices using micromembranes can be easily modified and represents a simple, adjustable fabrication process for the direct integration of nanowire meshes in multifunctional devices. This proof-of-concept study includes the deposition of SnO, WO, and Ge nanowires on the same chip.

Using non-nutritive sucking to support feeding development for premature infants: A commentary on approaches and current practice.

Non-nutritive sucking is often used with premature infants by either using a pacifier or an expressed breast nipple to support the introduction and development of early oral feeding. The pattern of non-nutritive sucking is distinct in that it involves two sucks per second in contrast to nutritive sucking which is one suck per second. Although some literature has identified that non-nutritive sucking has some benefit for the premature infant's feeding development, it is not entirely clear why such an approach is helpful as neurologically, activation of non-nutritive and nutritive skills are different.

Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods.

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, their high cost production and/or incompatibility with microfabrication technologies, due to the use of pre-deposited catalyst-seeds and/or high processing temperatures exceeding 900 °C, represent a drawback for a widespread use of these methods. Here, however, we report the synthesis of ZnO rods via a non-catalyzed vapor-solid mechanism enabled by using an aerosol-assisted chemical vapor deposition (CVD) method at 400 °C with zinc chloride (ZnCl2) as the precursor and ethanol as the carrier solvent. This method provides both single-step formation of ZnO rods and the possibility of their direct integration with various substrate types, including silicon, silicon-based micromachined platforms, quartz, or high heat resistant polymers.

ZnO Rods with Exposed {100} Facets Grown via a Self-Catalyzed Vapor-Solid Mechanism and Their Photocatalytic and Gas Sensing Properties.

We present a new method for vapor deposition of columnar ZnO structures in the form of rods on various substrates without the need for substrate modification with catalyst seed particles and at relatively low temperatures compared to other vapor deposition methods. These structures are used for the photodegradation of stearic acid (CHO) and the photoactivated detection of gases such as carbon monoxide (CO), ethanol (CHO), toluene (CH), and nitrogen dioxide (NO) at room temperature, showing improved selectivity compared to tests performed in themoactivated mode.