A new approach to antiglaucoma drugs: carbonic anhydrase inhibitors with or without NO donating moieties. Mechanism of action and preliminary pharmacology.

The clinically used sulfonamide carbonic anhydrase (CA, EC 4.2.1.1) inhibitor dorzolamide (DRZ), a new sulfonamide CA inhibitor also incorporating NO-donating moieties, NCX250, and isosorbide mononitrate (ISMN) (an NO-donating compound with no CA inhibitory properties) were investigated for their intraocular pressure (IOP) lowering effects in rabbits with carbomer-induced glaucoma. NCX250 was more effective than DRZ or ISMN on lowering IOP, increasing ocular hemodynamics, decreasing the inflammatory processes and ocular apoptosis in this animal model of glaucoma. NO participate to the regulation of IOP in glaucoma, having also antiapoptotic and anti-inflammatory effects. The ophthalmic artery, both systolic and diastolic velocities, were significantly reduced in NCX250-treated eyes in comparison to DRZ treated ones, suggesting thus a beneficial effect of NCX250 on the blood supply to the optic nerve. Combining CA inhibition with NO-donating moieties in the same compound offers an excellent approach for the management of glaucoma

Evaluación de la calidad de diferentes preparaciones típicas de aceitunas de mesa (cv Nocellara del Belice)

Commercially available green table olives of the Nocellara del Belice cultivar were processed in 26 companies. Three different processing conditions were used to obtain olive debittering: natural fermentation, “Castelvetrano” (a typical west Sicilian method) and cracked olives. The green olives packed into 200-500 mL glass jars were analyzed for physico-chemical characteristics that revealed statistical differences among the three debittering methods and a great difference among the samples, reflecting a low level of standardization achieved in these fermented products. The results showed an influence of the treatments on all physico-chemical parameters with the exception of total polyphenol content and lightness (L*) for which no significant differences were found. The average pH in the brine samples was under the hygienic limit of 4.5 with the exception of Castelvetrano olives which showed a higher pH values. The salt concentration of the brine samples appeared lower than the commercial limit according to the table olive trade standards. The brine samples were also analyzed for some microbiological parameters. Not all the samples showed acceptable commercial standards, because Clostridium perfringens, Staphylococcus aureus and coliform bacteria were detected in a few samples.Aceitunas verdes de mesa de la variedad “Nocellara del Belice” disponibles en el mercado fueron procesadas en 26 empresas. Tres condiciones diferentes de procesamiento se utilizaron para obtener aceitunas sin amargor: fermentación natural, Castelvetrano (un típico método del oeste de Sicilia) y aceitunas rajadas. Se analizaron las características fisicoquímicas de las aceitunas verdes en envases de vidrio de 200-500 mL que reveló diferencias significativas entre los tres métodos de eliminación del amargor y una gran diferencia entre las muestras, lo que refleja un bajo nivel de normalización conseguido en estos productos fermentados. Los resultados mostraron una influencia de los tratamientos en todos los parámetros físicoquímicos, con la excepción del contenido de polifenoles totales y de luminosidad (L *) para los que no se encontraron diferencias significativas. El promedio de pH de las muestras de salmuera se encontró por debajo del límite sanitario de 4,5, con la excepción de las aceitunas de Castelvetrano que mostró un valor de pH peligroso. La concentración de sal de las muestras de salmuera fue más baja que el límite comercial de acuerdo a las normas de la tabla del comercio de aceitunas. Algunos de los parámetros microbiológicos se analizaron también en las muestras de salmuera. No todas las muestras mostraron niveles aceptables de los valores comerciales establecidos, debido a que en algunas muestras se detectaron Clostridium perfringens, Staphylococcus aureus y bacterias coniformes

Antimicrobial and antibiofilm activities of new synthesized Silver Ultra-NanoClusters (SUNCs) against Helicobacter pylori

Helicobacter pylori colonizes approximately 50% of the world\u2019s population and it is the cause of chronic gastritis, peptic ulcer disease and gastric cancer. The increase of antibiotic resistance is one of the biggest challenges of our century due to its constant increase. In order to identify an alternative or adjuvant strategy to the standard antibiotic therapy, the in vitro activity of newly synthesized Silver Ultra-NanoClusters (SUNCs), characterized by an average size inferior to 5 nm, against clinical strains of Helicobacter pylori, with different antibiotic susceptibilities, was evaluated in this study. MICs and MBCs were determined by the broth microdilution method, whereas the effect of drug combinations by the checkerboard assay. The Minimum Biofilm Eradication Concentration (MBEC) was measured using AlamarBlue (AB) assay and Colony Forming Unit (CFU) counts. The cytotoxicity was evaluated by performing the MTT assay on AGS cell line. The inhibitory activity was expressed in terms of bacteriostatic and bactericidal potential, with MIC50, MIC90, and MBC50 of 0.33 mg/L against planktonic Helicobacter pylori strains. Using the fractional inhibitory concentration index, SUNCs showed synergism with metronidazole in one clinical strain, and very close to synergistic effect on the reference strain; the combination with clarythromicin evidenced an effect very close to synergism on both strains considered. The biofilm eradication was obtained after treatment with 2X, 3X and 4X MIC value. Moreover, SUNCs showed low toxicity on human cells and was effective in eradicating a mature biofilm produced by H. pylori. The data presented in this study demonstrate that SUNCs could represent a novel strategy for the treatment of H. pylori infections either alone or in combination with metronidazole

Synthesis and evaluation of thymol-based synthetic derivatives as dual-action inhibitors against different strains of h. pylori and AGS cell line

Following a similar approach on carvacrol-based derivatives, we investigated the synthesis and the microbiological screening against eight strains of H. pylori, and the cytotoxic activity against human gastric adenocarcinoma (AGS) cells of a new series of ether compounds based on the structure of thymol. Structural analysis comprehended elemental analysis and 1H/13C/19F NMR spectra. The analysis of structure-activity relationships within this molecular library of 38 structurally-related compounds reported that some chemical modifications of the OH group of thymol led to broad-spectrum growth inhibition on all isolates. Preferred substitutions were benzyl groups compared to alkyl chains, and the specific presence of functional groups at para position of the benzyl moiety such as 4-CN and 4-Ph endowed the most anti-H. pylori activity toward all the strains with minimum inhibitory concentration (MIC) values up to 4 µg/mL. Poly-substitution on the benzyl ring was not essential. Moreover, several compounds characterized by the lowest minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) values against H. pylori were also tested in order to verify a cytotoxic effect against AGS cells with respect to 5-fluorouracil and carvacrol. Three derivatives can be considered as new lead compounds alternative to current therapy to manage H. pylori infection, preventing the occurrence of severe gastric diseases. The present work confirms the possibility to use natural compounds as templates for the medicinal semi-synthesis

The Antibiofilm Effect of a Medical Device Containing TIAB on Microorganisms Associated with Surgical Site Infection

Surgical site infections (SSIs) represent the most common nosocomial infections, and surgical sutures are optimal surfaces for bacterial adhesion and biofilm formation. Staphylococcus spp., Enterococcus spp., and Escherichia coli are the most commonly isolated microorganisms. The aim of this research was to evaluate the antibiofilm activity of a medical device (MD) containing TIAB, which is a silver-nanotech patented product. The antibacterial effect was evaluated against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, and E. coli ATCC 25922 by assessing the minimum inhibitory concentration (MIC) by the Alamar Blue\uae (AB) assay. The antibiofilm effect was determined by evaluation of the minimum biofilm inhibitory concentration (MBIC) and colony-forming unit (CFU) count. Subsequently, the MD was applied on sutures exposed to the bacterial species. The antimicrobial and antibiofilm effects were evaluated by the agar diffusion test method, confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM). The MIC was determined for S. aureus and E. faecalis at 2 mg/mL, while the MBIC was 1.5 mg/mL for S. aureus and 1 mg/mL for E. faecalis. The formation of an inhibition zone around three different treated sutures confirmed the antimicrobial activity, while the SEM and CLSM analysis performed on the MD-treated sutures underlined the presence of a few adhesive cells, which were for the most part dead. The MD showed antimicrobial and antibiofilm activities versus S. aureus and E. faecalis, but a lower efficacy against E. coli. Surgical sutures coated with the MD have the potential to reduce SSIs as well as the risk of biofilm formation post-surgery

Identification and characterization of the a-CA in the outer membrane vesicles produced by Helicobacter pylori

The genome of Helicobacter pylori encodes for carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the aand b-CA classes, which together with urease, have a pivotal role in the acid acclimation of the microorganism within the human stomach. Recently, in the exoproteome of H. pylori, a CA with no indication of the corresponding class was identified. Here, using the protonography and the mass spectrometry, a CA belonging to the a-class was detected in the outer membrane vesicles (OMVs) generated by planktonic and biofilm phenotypes of four H. pylori strains. The amount of this metalloenzyme was higher in the planktonic OMVs (pOMVs) than in the biofilm OMVs (bOMVs). Furthermore, the content of a-CA increases over time in the pOMVs. The identification of the a-CA in pOMVs and bOMVs might shed new light on the role of this enzyme in the colonization, survival, persistence, and pathogenesis of H. pylor

Interaction-Dependent PCR: Identification of Ligand−Target Pairs from Libraries of Ligands and Libraries of Targets in a Single Solution-Phase Experiment

Interaction-dependent PCR (IDPCR) is a solution-phase method to identify binding partners from combined libraries of small-molecule ligands and targets in a single experiment. Binding between DNA-linked targets and DNA-linked ligands induces formation of an extendable duplex. Extension links codes that identify the ligand and target into one selectively amplifiable DNA molecule. In a model selection, IDPCR resulted in the enrichment of DNA encoding all five known protein−ligand pairs out of 67 599 possible sequences.Chemistry and Chemical Biolog