Although it is known that the first case of cancer was recorded in ancient Egypt around 1600 BC, it was not until 1917 during the First World War and the development of mustard gas that chemotherapy ...against cancer became relevant; however, its properties were not recognised until 1946 to later be used in patients. In this sense, the use of metallopharmaceuticals in cancer therapy was extensively explored until the 1960s with the discovery of cisplatin and its anticancer activity. From that date to the present, the search for more effective, more selective metallodrugs with fewer side effects has been an area of continuous exploration. Efforts have led to considering a wide variety of metals from the periodic table, mainly from the d‐block, as well as a wide variety of organic ligands, preferably with proven biological activity. In this sense, various research groups have found an ideal binder in Schiff bases, since their raw materials are easily accessible, their synthesis conditions are friendly and their denticity can be manipulated. Therefore, in this review, we have explored the anticancer and antitumor activity reported in the literature for coordination complexes of d‐block metals coordinated with tridentate Schiff bases (O N O and O N N) derived from salicylaldehyde. For this work, we have used the main scientific databases CCDC® and SciFinder®.
The search for more effective and selective metal‐based anticancer drugs with fewer side effects has been an area of continuous exploration. This has led to the exploration of a wide range of metals from the periodic table, mainly from the d‐block, as well as a wide variety of organic ligands, preferably with proven biological activity. Herein we review d‐block transition metal complexes including tridentate Schiff bases from salicylaldehyde (O N O and O N N) that exhibit good results in preliminary anticancer and antitumor activity assays.
In the search of nanomaterials to be used in drug delivery applications, Density Functional Theory calculations were implemented to study the interaction between graphene (G) and hexagonal boron ...nitride nanosheet (hBNN) with octahedral B12N12 fullerenes. These B12N12 fullerenes were considered in two cases: pristine and the modified one with boron-boron, nitrogen-nitrogen (tetragon) and boron-boron-boron (hexagon) homo-nuclear bonds. The whole systems were analyzed in the gas and aqueous phases. The results reveal for all these systems that the interaction is in the range of physisorption (Eads = from −0.03 to −0.37 eV) for both phases, limiting its functions as a vehicle. However, for the nano-composite: B12N12 fullerene modified and hBNNs, the values of average chemical reactivity and HOMO-LUMO gap decreased whereas the polarity was improved, thereby this combination of quantum descriptors lead them to be considered as potential vehicle for drug delivery.
When considering homonuclear bonds in B12N12 fullerene, adsorption on the surface of the sheet is improved. Display omitted
•Magnetic properties emerges in G and hBNNs-B12N12 fullerene nanocomposites.•Adsorption of homonuclear bonds B12N12 fullerene on hBN nanosheets is very viable.•The nature of the hBNNs-B12N12 fullerene, is strong and magnetic, may provide vehicle for drug delivery.
The adsorption of the carbon monoxide molecules onto the magnetic BN fullerene:B
6
−
and BN fullerene:C
6
−
nanocomposites is analyzed by means of the density functional theory. Three ...nanostructures were considered to evaluate the interactions generated when molecules of CO are added until reach the saturation: magnetic pristine BN fullerene, BN fullerene functionalized with magnetic B
6
and C
6
clusters. For all cases, it is obtained a chemical interaction that was increasing with the number of CO molecules adsorbed. The above pristine BNF:B
6
−
and BNF:C
6
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nanocomposites exhibit electronic behavior like-semiconductor; intrinsic magnetism (1.0 and 3.0
µ
B
), high polarity, and low-chemical reactivity respect to pristine BNF; these quantum descriptors they are modified slightly when the BN
−
fullerene, BNF:B
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and BNF:C
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nanocomposites are interacting with carbon monoxide molecule, moreover high chemisorption is obtained. Therefore, it is feasible to propose these nanocomposites as CO sensors.
•Total As and phenylarsenic compounds are analyzed in feed samples.•A microwave-assisted extraction method with 1.5M H3PO4 is applied.•The HPLC-UV/HG-AFS technique presents low-cost, simplicity, ...sensitivity and reproducibility.•ASA compound is found in chicken feed samples studied.•Unknown arsenic species are usually found in feed samples evaluated.
The development of a new method to determine the presence of the organoarsenic additives p-arsanilic acid (ASA), roxarsone (ROX) and nitarsone (NIT) in livestock feeds by high performance liquid chromatography coupled to ultraviolet oxidation hydride generation atomic fluorescence spectrometry (HPLC-UV/HG-AFS) after microwave assisted extraction (MAE) was proposed. Chromatographic separation was achieved on a C18 column with 2% acetic acid/methanol (96:4, v/v) as the mobile phase. The limits of detection (LODs) were 0.13, 0.09 and 0.08mgL−1, and the limits of quantification (LOQs) were 0.44, 0.30 and 0.28mgL−1. The relative standard deviations (RSDs) for ASA, ROX and NIT determined from five measurements of the mixed calibration standard were 3.3, 5.3, and 5.4%, respectively.
MAE extraction of phenylated arsenic compounds using 1.5M H3PO4 at 120°C for 45min allowed for maximum recoveries (%) of total arsenic (As) and organoarsenic species, with no degradation of these compounds. The extraction of total As was approximately 97%, and the As species recoveries were between 95.2 and 97.0%. The results of the analysis were validated using mass balance by comparing the sum of extracted As with the total concentration of As in the corresponding samples. The method was successfully applied to determine the presence of these compounds in feed samples. ASA was the only As species detected in chicken feed samples, with a concentration between 0.72 and 12.91mgkg−1.
Motivated by models proposed to explain Standard Model anomalies, and the unprecedented τ+τ− data to be collected by the Belle II experiment during the next years, we study the kinematics of tau pair ...decays and propose a new method to search for lepton flavor violating processes in tau lepton decays to invisible beyond Standard Model particles, such as τ → ℓα, where ℓ is either an electron or a muon, and α is a massive particle that escapes undetected. The new method improves by one order of magnitude the expected upper limit on the τ → ℓα production in 3 × 1 prong tau decays and establishes the possibility of performing this search in 1 × 1 prong tau decays which has not been previously considered.
A DFT scheme was adopted to study the noncovalent/covalent attachment of fullerenes (C60, Si24C36, and B24N36) to graphene and Fe-doped graphene nanosheets (FeG). Geometrical, energetic, and ...electronic properties related to the physical and chemical nature of the bonding were characterized. The results show that fullerenes are physisorbed on graphene with adsorption energies of 0.7–1.2 eV, while the chemisorption is reached on FeG by cycloadditions with adsorption energies of 1.6–4.4 eV and is depending on the topology of FeG. The origin of the stability was analyzed from chemical and physical viewpoints, applying methods such as atom-in-molecules (AIM), natural bond orbital (NBO), and energy decomposition analysis based on absolutely localized molecular orbitals (ALMO-EDA). It is shown that noncovalent graphene–fullerene hybrids are assembled by van der Waals interactions but are also governed by permanent electrostatic Coulombic interactions that contribute at least 31% to the binding stability and depending on the bond polarity of fullerenes. Otherwise, the cycloaddition of fullerenes with FeG is reached by the formation of highly polarized chemical bonds, which were described in a detailed orbital picture. The structural stability of the covalent complexes is dominated by the contribution of charge transfer and permanent electrostatic physical effects. Additionally, the polarizability is an intrinsic property of fullerenes that also determines its binding strength on graphene (up to 35%); in this way, the larger polarizability of fullerenes increases the interaction stability. Therefore, this work gives insights into the bonding properties governing the stability of hybrid materials formed by self-assembly of fullerenes onto emerging low-dimensional nanostructures.
Different lines of evidence have highlighted the role of IL-17A in the inflammatory process occurring in giant cell arteritis (GCA). The aim of the present study was to assess whether the IL17A locus ...influences GCA susceptibility and its clinical subphenotypes.
We carried out a large meta-analysis including a total of 1266 biopsy-proven GCA patients and 3779 healthy controls from four European populations (Spain, Italy, Germany and Norway). Five IL17A polymorphisms (rs4711998, rs8193036, rs3819024, rs2275913 and rs7747909) were selected by tagging and genotyped using TaqMan assays. Allelic combination and dependency tests were also performed.
In the pooled analysis, two of the five analysed polymorphisms showed evidence of association with GCA (rs2275913: PMH=1.85E-03, OR=1.17 (1.06-1.29); rs7747909: PMH=8.49E-03, OR=1.15 (1.04-1.27)). A clear trend of association was also found for the rs4711998 variant (PMH=0.059, OR=1.11 (1.00-1.23)). An independent effect of rs2275913 and rs4711998 was evident by conditional regression analysis. In addition, the haplotype harbouring the risk alleles better explained the observed association than the polymorphisms independently (likelihood p value <10(-05)).
Polymorphisms within the IL17A locus show a novel association with GCA. This finding supports the relevant role of the Th17 cells in this vasculitis pathophysiology.
To analyse the role of the PTPN22 and CSK genes, previously associated with autoimmunity, in the predisposition and clinical phenotypes of giant cell arteritis (GCA).
Our study population was ...composed of 911 patients diagnosed with biopsy-proven GCA and 8136 unaffected controls from a Spanish discovery cohort and three additional independent replication cohorts from Germany, Norway and the UK. Two functional PTPN22 polymorphisms (rs2476601/R620W and rs33996649/R263Q) and two variants of the CSK gene (rs1378942 and rs34933034) were genotyped using predesigned TaqMan assays.
The analysis of the discovery cohort provided evidence of association of PTPN22 rs2476601/R620W with GCA (PFDR=1.06E-04, OR=1.62, CI 95% 1.29 to 2.04). The association did not appear to follow a specific GCA subphenotype. No statistically significant differences between allele frequencies for the other PTPN22 and CSK genetic variants were evident either in the case/control or in stratified case analysis. To confirm the detected PTPN22 association, three replication cohorts were genotyped, and a consistent association between the PTPN22 rs2476601/R620W variant and GCA was evident in the overall meta-analysis (PMH=2.00E-06, OR=1.51, CI 95% 1.28 to 1.79).
Our results suggest that the PTPN22 polymorphism rs2476601/R620W plays an important role in the genetic risk to GCA.
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