Evaluation of the Safety and Potential Benefits of Beetroot-Based Dietary Supplements According to Their Elemental Composition.

The study aimed to assess the health value and safety associated with the consumption of the chosen 37 beetroot-based dietary supplements (DSs). An optimized and validated analytical procedure, using a method called microwave plasma atomic emission spectrometry (MP-AES), was developed to determine the profiles of 19 elements (Na, K, Fe, Ca, Pt, Zn, Cd, Cu, V, Co, Ni, Pb, Mo, Mg, Al, Mn, Sr, Cr, Ba) in the DSs. The products were assessed for compliance with the recommended daily doses for the chosen elements, and any deviations were identified.

Biocompatible antibiotic-loaded mesoporous silica/bioglass/collagen-based scaffolds as bone drug delivery systems.

Local delivery of antibiotics has gained increasing interest in the treatment of osteomyelitis due to its effectiveness and safety. Since the regeneration of bone tissue at the site of infection is as important as bacterial eradication, implantable drug delivery systems should not only release the drugs in a proper manner but also exert the osseointegration capability. Herein, we present an implantable drug delivery system in a scaffold form with a unique set of features for local treatment of osteomyelitis.

Antioxidant Capacity, Nitrite and Nitrate Content in Beetroot-Based Dietary Supplements.

Due to the high content of bioactive substances, beetroot and its preserves might be a valuable constituent of a diet. Research into the antioxidant capacity and content of nitrate (III) and (V) in beetroot-based dietary supplements (DSs) worldwide is limited. The Folin-Ciocalteu method, CUPRAC, DPPH, and Griess methods were used to determine total antioxidant capacity, total phenolic content, nitrites, and nitrates content in fifty DSs and twenty beetroot samples.

Bioglass obtained via one-pot synthesis as osseointegrative drug delivery system.

Osseointegration is a fundamental process during which implantable biomaterial integrates with host bone tissue. The surgical procedure of biomaterial implantation is highly associated with the risk of bacterial infection. Thus, the research continues for biodegradable bone void fillers which are able to stimulate the bone tissue regeneration and locally deliver the antibacterial agent.

Assessment of the Mineral Composition and the Selected Physicochemical Parameters of Dietary Supplements Containing Green Tea Extracts.

Our aim was to assess the mineral composition as well as the physicochemical quality of green tea-based dietary supplements (capsules and tablets) with respect to average weight, size and shape, friability, breaking force and disintegration time. Products were analysed by flame atomic absorption spectrometry for Ca, K, Mg, Na, Cr, Cu, Fe, Zn, Mn, Pb and Cd. Approximately 60% of the analysed supplements met the requirements of European and Polish regulations.

Antioxidant-Loaded Mesoporous Silica-An Evaluation of the Physicochemical Properties.

The dangerous effects of oxidative stress can be alleviated by antioxidants—substances with the ability to prevent damage caused by reactive oxygen species. The adsorption of antioxidants onto nanocarriers is a well-known method that might protect them against rough environ-mental conditions. The aim of this study was to investigate the adsorption and desorption of gallic acid (GA), protocatechuic acid (PCA), chlorogenic acid (CGA), and 4-hydroxybenzoic acid (4-HBA) using commercially available mesoporous silica materials (MSMs), both parent (i.

Mineral Composition of Dietary Supplements-Analytical and Chemometric Approach.

There is a lack of data on the actual composition and effectiveness of beetroot-based dietary supplements. The research aimed to determine the profile of 22 elements (Na, K, Ca, Mg, P, Fe, As, Se, Zn, Cu, Ag, Co, Ni, Mo, Al, Mn, Sr, Cr, Ba, Li, Pb, Cd) in beetroot and its supplements by the microwave plasma atomic emission spectrometry (MP-AES) method. The analytical procedure was optimised and validated.

Evaluation of Physicochemical Properties of Beetroot-Based Dietary Supplements.

In the European Union, no specific requirements for the physicochemical parameters of dietary supplements have been established, contrary to the United States of America. This research aimed to assess the selected physical parameters of 31 commercially available beetroot-based dietary supplements in the form of tablets and capsules following the United States Pharmacopoeia (USP) guidelines and the Food and Drug Administration (FDA) recommendations. There was also estimated zinc and iron content by atomic absorption spectroscopy with flame detection.

Mesoporous Silica-Bioglass Composite Pellets as Bone Drug Delivery System with Mineralization Potential.

For decades, local bone drug delivery systems have been investigated in terms of their application in regenerative medicine. Among them, inorganic polymers based on amorphous silica have been widely explored. In this work, we combined two types of amorphous silica: bioglass and doxycycline-loaded mesoporous silica MCM-41 into the form of spherical granules (pellets) as a bifunctional bone drug delivery system.

Molecular Mechanism of Thymidylate Synthase Inhibition by N-Hydroxy-dCMP in View of Spectrophotometric and Crystallographic Studies.

Novel evidence is presented allowing further clarification of the mechanism of the slow-binding thymidylate synthase (TS) inhibition by N-hydroxy-dCMP (N-OH-dCMP). Spectrophotometric monitoring documented time- and temperature-, and N-OH-dCMP-dependent TS-catalyzed dihydrofolate production, accompanying the mouse enzyme incubation with N-OH-dCMP and N-methylenetetrahydrofolate, known to inactivate the enzyme by the covalent binding of the inhibitor, suggesting the demonstrated reaction to be uncoupled from the pyrimidine C(5) methylation. The latter was in accord with the hypothesis based on the previously presented structure of mouse TS (cf.

Advanced Spectroscopy and APBS Modeling for Determination of the Role of His190 and Trp103 in Mouse Thymidylate Synthase Interaction with Selected dUMP Analogues.

A homo-dimeric enzyme, thymidylate synthase (TS), has been a long-standing molecular target in chemotherapy. To further elucidate properties and interactions with ligands of wild-type mouse thymidylate synthase (mTS) and its two single mutants, H190A and W103G, spectroscopic and theoretical investigations have been employed. In these mutants, histidine at position 190 and tryptophan at position 103 are substituted with alanine and glycine, respectively.

Microwave-Assisted Fabrication of Mesoporous Silica-Calcium Phosphate Composites for Dental Application.

Herein, the microwave-assisted wet precipitation method was used to obtain materials consisting of mesoporous silica (SBA-15) and calcium orthophosphates (CaP). Composites were prepared through immersion of mesoporous silica in different calcification coating solutions and then exposed to microwave radiation. The composites were characterized in terms of molecular structure, crystallinity, morphology, chemical composition, and mineralization potential by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX).

Mesoporous silica pellets as bifunctional bone drug delivery system for cefazolin.

For decades, bone drug delivery systems dedicated for osteomyelitis treatment have been investigated as bifunctional materials that exhibit prolonged drug release and mineralization potential. Herein, composite-type pellets based on cefazolin-loaded amino-modified mesoporous silica SBA-15 and microwave-assisted hydroxyapatite were investigated as potential bone drug delivery system in vitro. Pellets were obtained by granulation, extrusion and spheronization methods in laboratory scale and studied in terms of physical properties, drug release, mineralization potential, antimicrobial activity and cytotoxicity towards human osteoblasts.

Silica-Polymer Composites as the Novel Antibiotic Delivery Systems for Bone Tissue Infection.

Bone tissue inflammation, , is commonly caused by bacterial invasion and requires prolonged antibiotic therapy for weeks or months. Thus, the aim of this study was to develop novel silica-polymer local bone antibiotic delivery systems characterized by a sustained release of ciprofloxacin (CIP) which remain active against for a few weeks, and do not have a toxic effect towards human osteoblasts. Four formulations composed of ethylcellulose (EC), polydimethylsiloxane (PDMS), freeze-dried CIP, and CIP-adsorbed mesoporous silica materials (MCM-41-CIP) were prepared via solvent-evaporation blending method.

Biphasic composite of calcium phosphate-based mesoporous silica as a novel bone drug delivery system.

We reported the new biphasic composites of calcium phosphate and mesoporous silica material (CaP@MSi) in the form of powders and pellets as a potential bone drug delivery system for doxycycline hydrochloride (DOX). The CaP@MSi powders were synthesized by cationic surfactant-templating method. The effects of 10, 20, and 30% CaP content in the CaP@MSi powders on the molecular surface structure, the cytotoxicity against osteoblast cells in vitro, and the mineralization potential in simulated body fluid were investigated.

Thymidylate synthase-catalyzed, tetrahydrofolate-dependent self-inactivation by 5-FdUMP.

In view of previous crystallographic studies, N-hydroxy-dCMP, a slow-binding thymidylate synthase inhibitor apparently caused "uncoupling" of the two thymidylate synthase-catalyzed reactions, including the N-methylenetetrahydrofolate one-carbon group transfer and reduction, suggesting the enzyme's capacity to use tetrahydrofolate as a cofactor reducing the pyrimidine ring C(5) in the absence of the 5-methylene group. Testing the latter interpretation, a possibility was examined of a TS-catalyzed covalent self-modification/self-inactivation with certain pyrimidine deoxynucleotides, including 5-fluoro-dUMP and N-hydroxy-dCMP, that would be promoted by tetrahydrofolate and accompanied with its parallel oxidation to dihydrofolate. Electrophoretic analysis showed mouse recombinant TS protein to form, in the presence of tetrahydrofolate, a covalently bound, electrophoretically separable 5-fluoro-dUMP-thymidylate synthase complex, similar to that produced in the presence of N-methylenetetrahydrofolate.

The Effect of Polydimethylsiloxane-Ethylcellulose Coating Blends on the Surface Characterization and Drug Release of Ciprofloxacin-Loaded Mesoporous Silica.

In this study, we obtained novel solid films composed of ciprofloxacin-loaded mesoporous silica materials (CIP-loaded MCM-41) and polymer coating blends. Polymer coating blends were composed of ethylcellulose (EC) with various levels of polydimethylsiloxane (PDMS, 0, 1, 2% (/)). The solid films were prepared via the solvent-evaporation molding method and characterized by using scanning electron microscopy (SEM), optical profilometry, and wettability analyses.

Use of Materials Based on Polymeric Silica as Bone-Targeted Drug Delivery Systems for Metronidazole.

Mesostructured ordered silica-based materials are the promising candidates for local drug delivery systems in bone disease due to their uniform pore size and distribution, and high surface area which affect their excellent adsorption properties, good biocompatibility and bioactivity, and versatile functionalization so that their properties can be controlled. Ordered mesoporous silica (MCM-41 type) was synthesized by a surfactant-assisted sol-gel process using tetraethoxysilane as a silica precursor and hexadecyltrimethylammonium bromide as the structure-directing agent. Functionalized silica materials containing various types of organic groups (3-aminopropyl, 3-mercaptopropyl, or 3-glycidyloxypropyl groups) were synthesized by the post-grafting method onto pre-made mesoporous silica.

Surface-Activated Fibre-Like SBA-15 as Drug Carriers for Bone Diseases.

Here, we report an inorganic hexagonally ordered mesoporous fibre-like carrier made of silica as an effective drug delivery system with mineralisation potential. Fibre-like SBA-15 has been modified by employing a simple surface activation (rehydroxylation) procedure. The surface-rehydroxylated fibre-like SBA-15 (SBA-15-R) was used to investigate the possible mechanism of hydroxyapatite (HA) nucleation and deposition onto silica's surface after immersion in simulated body fluid (SBF).

A synergistic effect of phosphate, pH and Phe159 substitution on the formycin A association to the E. coli purine nucleoside phosphorylase.

A steady-state absorption and emission spectroscopy was used to create a comprehensive work and to study the interaction of the wild type Escherichia coli purine nucleoside phosphorylase and its mutants, PNPF159Y and PNPF159A, with a potent E. coli PNP inhibitor - formycin A. The absorption and emission spectra were recorded in the presence and absence of the phosphate at the 50 mM concentration.

Towards understanding the E. coli PNP binding mechanism and FRET absence between E. coli PNP and formycin A.

The aim of this study is threefold: (1) augmentation of the knowledge of the E. coli PNP binding mechanism; (2) explanation of the previously observed 'lack of FRET' phenomenon and (3) an introduction of the correction (modified method) for FRET efficiency calculation in the PNP-FA complexes. We present fluorescence studies of the two E.

The effect of wool hydrolysates on squamous cell carcinoma cells in vitro. Possible implications for cancer treatment.

Squamous cell carcinoma of the skin is the second most common cutaneous malignancy. Despite various available treatment methods and advances in noninvasive diagnostic techniques, the incidence of metastatic cutaneous squamous cell carcinoma is rising. Deficiency in effective preventive or treatment methods of transformed keratinocytes leads to necessity of searching for new anticancer agents.

Formulation and In Vitro Characterization of Bioactive Mesoporous Silica with Doxorubicin and Metronidazole Intended for Bone Treatment and Regeneration.

The purpose of this study was to evaluate the surface mineralization activity and in vitro drug behavior potential of two forms of mesoporous silica: powder and granulate. Ordered mesoporous SiO powder was synthesized by surfactant-assisted sol-gel process using tetraethoxysilane as a silica precursor and hexadecyltrimethylammonium bromide as the structure-directing agent. The granulate was prepared using silica powder and ethyl cellulose as a binding agent.

Preparation and in vitro characterisation of bioactive mesoporous silica microparticles for drug delivery applications.

The aim of this study was to evaluate the surface mineralization activity and in vitro drug behaviour potential of new mesoporous silica microparticles (MSM). The unmodified MSM (MSM-0%Ca) and calcium-modified MSM (MSM-5%Ca, MSM-15%Ca, MSM-25%Ca) were prepared using the self-assembling method. Calcium diethoxide was used as a calcium precursor.

A QM-MD simulation approach to the analysis of FRET processes in (bio)molecular systems. A case study: complexes of E. coli purine nucleoside phosphorylase and its mutants with formycin A.

Predicting FRET pathways in proteins using computer simulation techniques is very important for reliable interpretation of experimental data. A novel and relatively simple methodology has been developed and applied to purine nucleoside phosphorylase (PNP) complexed with a fluorescent ligand - formycin A (FA). FRET occurs between an excited Tyr residue (D*) and FA (A).