Harmonization and transferability of performance assessment: experience from four serum aluminum proficiency testing schemes

Proficiency testing schemes monitor laboratory performance and provide a stimulus for improvement in accuracy. Where several schemes operate in the same analytical sector, there are risks that assessments of performance may be in conflict. Performance assessment for the determination of trace elements such as aluminum in serum is particularly important due to the high risk of contamination and therefore erroneous results. The objectives of this work were (1) to compare several mathematical models to establish a predefined standard deviation for proficiency assessment and (2) to evaluate the influence of instrumental methods and proficiency testing scheme on the assessment of performance for serum aluminum measurements. For this purpose, three samples were sent to the participants of four proficiency testing schemes. Assigned values were calculated according to algorithm A according to ISO 13528 and standard deviation for proficiency assessment according to three methods based on individual variability, state of the art or previous proficiency testing results. The method based on individual variability produced a more stringent standard deviation compared to analytical imprecision based on the state of the art. The instrumental methods gave similar results, whereas significant differences were observed between the four proficiency testing schemes indicating that harmonization of the standard deviation for proficiency assessment fails to allow transferability from one proficiency testing scheme to another and that additional factor(s) contribute to variability in performance assessment.     

Simultaneous Detection of Carbon Monoxide and Viscosity Changes in Cells

A new family of robust, non-toxic, water-compatible ruthenium(II) vinyl probes allows the rapid, selective and sensitive detection of endogenous carbon monoxide (CO) in live mammalian cells under normoxic and hypoxic conditions. Uniquely, these probes incorporate a viscosity-sensitive BODIPY fluorophore that allows the measurement of microscopic viscosity in live cells via fluorescence lifetime imaging microscopy (FLIM) while also monitoring CO levels. This is the first example of a probe that can simultaneously detect CO alongside small viscosity changes in organelles of live cells.     

Ferromagnetically Coupled S=1 Chains in Crystals of Verdazyl-Nitronyl Nitroxide Diradicals

Thermally stable organic diradicals with a triplet ground state along with large singlet-triplet energy gap have significant potential for advanced technological applications. A series of phenylene-bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium-catalyzed cross-coupling reaction of iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔE_ST≈−64 cm⁻¹) and FM (ΔE_ST≥25 and 100 cm⁻¹) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para- or meta-phenylene) and by the type of oxoverdazyl block (C-linked or N-linked). Upon crystallization, diradicals with the triplet ground state form unique one-dimensional exchange-coupled chains with strong intra- and weak inter-diradical ferromagnetic coupling.     

Synthesis of (1′S*,2R*,3R*)- and (1′S*,2R*,3S*)-N-arylsulfonyl-2-(1′-halogenethyl)-3-methylindolines and their selective toxicity against SH-SY5Y cell line

N-tosyl-2- and N-tosyl-4-halogen-substituted derivatives of 2-(1-methylbut-2-en-1-yl)aniline were synthesized and their molecular iodine-mediated cyclization was investigated. The cyclization upon interaction of N-tosyl-6-methyl-2-(1-methylbut-2-en-1-yl)aniline with molecular iodine in methyl tert-butyl ether or acetonitrile was studied, as well as the interaction of this sulfonamide with N-bromosucinimide in dichloromethane. Synthesized (2R*,3R*)- and (2R*,3S*)-N-arylsulfonyl-2-(1-halogenoethyl)-3-methylindoline derivatives showed cytotoxic activity against HEK293 cells, SH-SY5Y, Jurkat, and HepG2 cell lines. The compounds (2R*,3S*)-N-arylsulfonyl-7-bromo-2-(1-halogenoethyl)-3-methylindoline cis- 4a , stereoisomeric (2R*,3R*)-trans- 4h and (2R*,3S*)-N-tosyl-7-chloro-2-(1-halogenoethyl)-3-methylindoline cis- 4h demonstrated selective toxicity against SH-SY5Y cell line (IC₅₀ ≈ 3 ÷ 5 μM), and did not affect HEK293, Jurkat, and HepG2 cells.     

Bioactive Properties and Phenolic Compound Profiles of Turnip-Rooted,Plain-Leafed and Curly-Leafed Parsley Cultivars

Petroselinum crispum Mill., Fuss., is a culinary vegetable used as an aromatic herb that garnishes and flavours a great variety of dishes. In the present study, the chemical profiles and bioactivities of leaf samples from 25 cultivars (three types: plain- and curly-leafed and turnip-rooted) from this species were assessed. Seven phenolic compounds were identified in all the varieties, including apigenin and kaempherol derivates. Apigenin-O-pentoside-O-hexoside was the major compound in all the tested parsley types (20, 22 and 13 mg/g of extract, respectively) and responsible for its excellent antioxidant activity, also investigated in this study. Antimicrobial activities were also explored, and the results revealed a good bioactivity against specific tested pathogens, such as bacteria and fungi. In conclusion, the leaves of all the types of P. crispum are a good source of natural bioactive compounds that confer health benefits, and thus, they should be part of a balanced and diversified diet.     

From 1D to 2D Cd(II) and Zn(II) Coordination Networks by Replacing Monocarboxylate with Dicarboxylates in Partnership with Azine Ligands: Synthesis,Crystal Structures,Inclusion, and Emission Properties

Eight mixed-ligand coordination networks, [Cd(2-aba)(NO₃)(4-bphz)_3/2]_n·n(dmf) (1), [Cd(2-aba)₂(4-bphz)]_n·0.75n(dmf) (2), [Cd(seb)(4-bphz)]_n·n(H₂O) (3), [Cd(seb)(4-bpmhz)]_n·n(H₂O) (4), [Cd(hpa)(3-bphz)]_n (5), [Zn(1,3-bdc)(3-bpmhz)]_n·n(MeOH) (6), [Cd(1,3-bdc)(3-bpmhz)]_n ·0.5n(H₂O)·0.5n(EtOH) (7), and [Cd(NO₃)₂(3-bphz)(bpe)]_n·n(3-bphz) (8) were obtained by interplay of cadmium nitrate tetrahydrate or zinc nitrate hexahydrate with 2-aminobenzenecarboxylic acid (H(2-aba)), three dicarboxylic acids, sebacic (decanedioic acid, H₂seb), homophthalic (2-(carboxymethyl)benzoic acid, H₂hpa), isophthalic (1,3-benzenedicarboxylic acid, H₂(1,3-bdc)) acids, bis(4-pyridyl)ethane (bpe) and with four azine ligands, 1,2-bis(pyridin-4-ylmethylene)hydrazine (4-bphz), 1,2-bis(1-(pyridin-4-yl)ethylidene) hydrazine (4-bpmhz), 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-bphz), and 1,2-bis(1-(pyridin-3-yl) ethylidene)hydrazine (3-bpmhz). Compounds 1 and 2 are 1D coordination polymers, while compounds 3–8 are 2D coordination polymers. All compounds were characterized by spectroscopic and X-ray diffraction methods of analysis. The solvent uptakes and stabilities to the guest evacuation were studied and compared for 1D and 2D coordination networks. The de-solvated forms revealed a significant increase of emission in comparison with the as-synthesized crystals.     

Effects of Grape Polyphenols on the Life Span and Neuroinflammatory Alterations Related to Neurodegenerative Parkinson Disease-Like Disturbances in Mice

Functional nutrition is a valuable supplementation to dietary therapy. Functional foods are enriched with biologically active substances. Plant polyphenols attract particular attention due to multiple beneficial properties attributed to their high antioxidant and other biological activities. We assessed the effect of grape polyphenols on the life span of C57BL/6 mice and on behavioral and neuroinflammatory alterations in a transgenic mouse model of Parkinson disease (PD) with overexpression of the A53T-mutant human α-synuclein. C57BL/6 mice were given a dietary supplement containing grape polyphenol concentrate (GPC—1.5 mL/kg/day) with drinking water from the age of 6–8 weeks for life. Transgenic PD mice received GPC beginning at the age of 10 weeks for four months. GPC significantly influenced the cumulative proportion of surviving and substantially augmented the average life span in mice. In the transgenic PD model, the grape polyphenol (GP) diet enhanced memory reconsolidation and diminished memory extinction in a passive avoidance test. Behavioral effects of GP treatment were accompanied by a decrease in α-synuclein accumulation in the frontal cortex and a reduction in the expression of neuroinflammatory markers (IBA1 and CD54) in the frontal cortex and hippocampus. Thus, a GP-rich diet is recommended as promising functional nutrition for aging people and patients with neurodegenerative disorders.     

Characterization of Phenolic Compounds,Vitamin E and Fatty Acids from Monovarietal Virgin Olive Oils of “Picholine marocaine” Cultivar

Olive oil is an important product in the Mediterranean diet, due to its health benefits and sensorial characteristics. Picholine marocaine is the most cultivated variety in Morocco. The present research aims to evaluate the phenolic compounds, vitamin E and fatty acids of commercial Picholine marocaine virgin olive oils (VOOs) from five different North Moroccan provinces (Chefchaouen, Taounate, Errachidia, Beni Mellal and Taza), using HPLC-photodiode array (PDA)/electrospray ionization (ESI)-MS, normal phase (NP)-HPLC/ fluorescence detector (FLD) and GC-flame ionization detector (FID)/MS, respectively. The obtained results showed an average content of 130.0 mg kg⁻¹ of secoiridoids (oleuropein aglycone, 10-hydroxy-oleuropein aglycone and ligstroside aglycone, oleocanthal and oleacein), 108.1 mg kg⁻¹ of phenolic alcohols (tyrosol and hydroxytyrosol), 34.7 mg kg⁻¹ of phenolic acids (caffeic acid, ferulic acid and elenolic acid), and 8.24 mg kg⁻¹ of flavonoids (luteolin, luteolin glucoside, apigenin). With regard to vitamin E, α-tocopherol was the most abundant vitamin E (57.9 mg kg⁻¹), followed by α-tocotrienol (2.5 mg kg⁻¹), γ-tocopherol (4.5 mg kg⁻¹) and β-tocopherol (1.9 mg kg⁻¹), while δ-tocopherol was not detected. Moreover, 14 fatty acids were found and, among them, oleic acid (76.1%), linoleic acid (8.1%) palmitic acid (8.7%) and stearic acid (2.5%) were the major fatty acids detected. Finally, heat map and principal component analysis allowed us to classify the studied provinces in terms of VOO chemical composition: Chefchaouen (tyrosol and hydroxytyrosol), Taounate (oleuropein aglycone), Errachidia (ferulic acid, w-3 and w-6), Beni Mellal (oleocanthal) and Taza (luteolin and oleic acid).     

Development of Phenothiazine Hybrids with Potential Medicinal Interest: A Review

The molecular hybridization approach has been used to develop compounds with improved efficacy by combining two or more pharmacophores of bioactive scaffolds. In this context, hybridization of various relevant pharmacophores with phenothiazine derivatives has resulted in pertinent compounds with diverse biological activities, interacting with specific or multiple targets. In fact, the development of new drugs or drug candidates based on phenothiazine system has been a promising approach due to the diverse activities associated with this tricyclic system, traditionally present in compounds with antipsychotic, antihistaminic and antimuscarinic effects. Actually, the pharmacological actions of phenothiazine hybrids include promising antibacterial, antifungal, anticancer, anti-inflammatory, antimalarial, analgesic and multi-drug resistance reversal properties. The present review summarizes the progress in the development of phenothiazine hybrids and their biological activity.     

Identification of pyrrolo-pyridine derivatives as novel class of antibacterials

Molecular Diversity - A series of 5-oxo-4H-pyrrolo[3,2-b]pyridine derivatives was identified as novel class of highly potent antibacterial agents during an extensive large-scale high-throughput...