Advancements in electron paramagnetic resonance (EPR) spectroscopy: A comprehensive tool for pharmaceutical research.

Electron paramagnetic resonance (EPR) spectroscopy has long been established across various scientific disciplines for characterizing organic radicals, organometallic complexes, protein structures and dynamics, polymerization processes, and radical degradation phenomena. Despite its extensive utility in these areas, EPR spectroscopy's application within pharmaceutical science has historically been constrained, primarily due to factors such as high equipment costs, a steep learning curve, complex spectral deconvolution and analysis, and a traditional lack of emphasis on single-electron chemistry in pharmaceutical research. This review aims to provide a thorough examination of EPR spectroscopy's applications in analyzing a wide array of para-magnetic species relevant to pharmaceutical research.

Light-induced rearrangement from macrocyclic to bicyclic lactam: A case study of -chlorinated laurolactam.

Converting macrocycle lactams into bicyclic lactams is proposed as an additional way to further increase the metabolic stability of peptide-based drugs. Unfortunately, the synthesis of bicyclic lactams has to start almost from scratch. This study explores the Hofmann-Löffler-Freytag (HLF) reaction mechanism and products as a potential late-stage functionalisation strategy for facile conversion of macrocyclic to bicyclic ring.

Unveiling the antiglioblastoma potential of harmicens, harmine and ferrocene hybrids.

The poor prognosis of glioblastoma multiforme, inadequate treatment options, and growing drug resistance urge the need to find new effective agents. Due to the significant anti-cancer potential of harmicens, hybrid compounds which comprise harmine/β-carboline and ferrocene moiety, we investigated their antiglioblastoma potential and mechanism of action (inhibition of DYRK1A, Hsp90, anti-oxidative activity). The results have shown that triazole-type harmicens, namely , with a ferrocene moiety in C-3 position of the β-carboline ring ( = 3.

Prediction of spirometry outcome in Croatian patients with chronic obstructive pulmonary disease.

The current study offers an extensive examination of the influence of 29 diverse parameters on spirometry measurement variables in a cohort of 534 patients with chronic obstructive pulmonary disease (COPD) from five different centers in Croatia. The study elucidates both the magnitude and direction of the effect exerted by the 29 predictors on forced vital capacity (FVC), forced expiratory volume in one second (FEV1), the ratio FEV1/FVC, and predicted forced expiratory flow at 50% of FVC. Additionally, the development of prediction models for these parameters has been undertaken using several statistical methods.

Regioselective Rearrangement of Nitrogen- and Carbon-Centered Radical Intermediates in the Hofmann-Löffler-Freytag Reaction.

The Hofmann-Löffler-Freytag (HLF) reaction serves as a late-stage functionalization technique for generating pyrrolidine heterocyclic ring systems. Contemporary HLF protocols utilize in situ halogenated sulfonamides as precursors in the radical-mediated rearrangement cycle. Despite its well-established reaction mechanism, experiments toward the detection of radical intermediates using EPR techniques have only recently been attempted.

Body composition, pulmonary function tests, exercise capacity, and quality of life in chronic obstructive pulmonary disease patients with obesity.

Purpose Of The Study: Larger proportions of chronic obstructive pulmonary disease (COPD) patients are currently overweight or with obesity than underweight, and the combination of COPD and obesity is increasing. The purpose of this study was to investigate differences in the body composition, pulmonary function tests, exercise capacity, and health-related quality of life among normal weight, overweight, and obese patients with COPD.

Study Design: A total of 514 patients with COPD were included in the study.

Thallium Toxicity and its Interference with Potassium Pathways Tested on Various Cell Lines.

Thallium (Tl) is a highly toxic heavy metal whose mechanism of toxicity is still not completely understood. The aim of this study was to test Tl cytotoxicity on several cell lines of different tissue origin in order to clarify specific Tl toxicity to a particular organ. In addition, possible interference of Tl with cell potassium (K) transport was examined.

Differences in nutritional status of patients with chronic obstructive pulmonary disease between Mediterranean and non-Mediterranean regions in Croatia.

The nutritional status of patients with chronic obstructive pulmonary disease (COPD) is a significant factor that influences the prognosis of the disease. This observational study aimed to analyze the nutritional status of COPD patients and assess the associations between nutritional status, disease severity, and exercise capacity in four different regions of Croatia. In this multicenter study, 534 COPD patients were recruited and evaluated concerning fat-free mass (FFM), FFM index (FFMI), skeletal muscle mass index (SMMI), phase angle (PhA), pulmonary function tests, and the 6-minute walk test (6MWT).

Association between Nutritional Status, Lifestyle Habits, and Disease Activity in Dalmatian Patients with Rheumatoid Arthritis.

The aim of this study was to evaluate body composition, handgrip strength, quality of life, disease duration and activity and lifestyle habits in patients with rheumatoid arthritis (RA) and to evaluate possible associations between all of the abovementioned factors. Seventy-five stable RA patients were included. Data on sociodemographic data, disease activity, quality of life, nutritional risk, body mass composition, anthropometric parameters, and clinical and laboratory parameters were collected for each study participant.

Glycosylation Profile of Immunoglobulin G Is Cross-Sectionally Associated With Cardiovascular Disease Risk Score and Subclinical Atherosclerosis in Two Independent Cohorts.

Rationale: One measure of protein glycosylation (GlycA) has been reported to predict higher cardiovascular risk by reflecting inflammatory pathways.

Objective: The main objective of this study is to assess the role of a comprehensive panel of IgG glycosylation traits on traditional risk factors for cardiovascular disease and on presence of subclinical atherosclerosis in addition to GlycA.

Methods And Results: We measured 76 IgG glycosylation traits in 2970 women (age range, 40-79 years) from the TwinsUK cohort and correlated it to their estimated 10-year atherosclerotic cardiovascular disease risk score and their carotid and femoral plaque measured by ultrasound imaging.

Physical mechanisms and methods employed in drug delivery to tumors.

In addition to several well-known drug delivery strategies developed to facilitate effective chemotherapy with anticancer agents, some new approaches have been recently established, based on specific effects arising from the applications of ultrasound, magnetic and electric fields on drug delivery systems. This paper gives an overview of newly developed methods of drug delivery to tumors and of the related anticancer therapies based on the combined use of different physical methods and specific drug carriers. The conventional strategies and new approaches have been put into perspective to revisit the existing and to propose new directions to overcome the threatening problem of cancer diseases.

Evaluation of antioxidative activity of Croatian propolis samples using DPPH* and ABTS*+ stable free radical assays.

Propolis is one of the richest sources of plant phenolics (flavonoids and phenolic acids), which are widely recognized as rather strong antioxidants. The aim of our work was to use colored stable free radical (DPPH* and ABTS*+) spectrophotometric and thin-layer chromatographic (TLC) assays to study the antioxidative behavior of the phenolics (caffeic acid, galangin and pinocembrin) most commonly present in Croatian propolis samples obtained from different Croatian regions. We propose a mathematical model providing a more sophisticated interpretation of the obtained results and a new parameter named antioxidative efficiency (AOE) is introduced.

Oxidation of hydroxyurea with oxovanadium(V) ions in acidic aqueous solution.

Hydroxyurea (HU) effectively reduces vanadium(V) into vanadium(IV) species (hereafter V(V) and V(IV) species, respectively) in acidic aqueous solution via the formation of a transient complex followed by an electron transfer process that includes the formation and subsequent fading out of a free radical, U* (U* identical with H(2)N-C(=O)N(H)O*). The electron paramagnetic resonance (EPR) spectra of U* in H(2)O/D(2)O solutions suggest that the unpaired electron is located predominantly on the hydroxamate hydroxyl-oxygen atom. Visible and V(IV)-EPR spectroscopic data reveal HU as a two-electron donor, whereas formation of U*, which reduces a second V(V), indicates that electron transfer occurs in two successive one-electron steps.

EPR study of a copper impurity center in a single crystal of 2-thiothymine.

EPR spectroscopy was used to study the complex formed in crystals of 5-methyl-2-thiouracil (2-thiothymine) containing traces of copper. The copper impurities, originally present as Cu(I)-complex of 2-thiothymine in the lattice of 2-thiothymine, are transformed into paramagnetic Cu(II)-complex by ionizing radiation. It was found that the complex is planar, the plane being defined by two pairs of S and N atoms, from two adjacent 2-thiothymine molecules.

EPR study of a copper center in a single crystal of cytosine monohydrate.

Copper is found incorporated into the crystal structure of cytosine monohydrate grown from aqueous solution of commercially available cytosine. Upon ionizing irradiation, the crystals exhibited the electron paramagnetic resonance (EPR) spectra characteristic of Cu(II) complex. Planar coordination bonding to the cupric ion, having three nitrogen atoms and an oxygen as ligands, is interpreted to bridge two cytosine molecules, replacing the two cytosine-cytosine hydrogen bonds present in pure crystals.

Betainohydroxamic acid chloride.

The title compound, N-hydroxy-2-(trimethylammonio)acetamide chloride, C(5)H(13)N(2)O(2)(+).Cl(-), has been synthesized and structurally characterized. The structure consists of betainohydroxamic acid cations and Cl(-) anions linked by N-H.

5-Methyl-2-thiouracil.

The molecular structure of the title compound, also known as 2-thiothymine [systematic name: 2,3-dihydro-5-methyl-2-thioxopyrimidin-4(1H)-one], C(5)H(6)N(2)OS, is similar to that of thymine, with only small changes in the ring structure, apart from a significant difference at the substitution site [S=C = 1.674 (1) A]. The molecules are connected by hydrogen bonds, with N-H.