Design of New Bis(1,2,3-triazol-1-yl)methane-Based Nitrogen Ligands: Synthesis and Coordination Chemistry.

The reaction between bis(1,2,3-triazol-1-yl)methane derivatives and nBuLi and various aldehydes, yielded novel neutral ligand precursors incorporating alcohol functional groups. The resulting compounds exhibited distinct characteristics depending on the steric hindrance of the aldehyde employed. In instances where aromatic aldehydes were utilized, functionalization occurred at the methine group bridging both triazole rings. Conversely, the use of pivalic aldehyde prompted functionalization at the C5 position of the triazole ring. These compounds were subsequently employed as ligand precursors in the synthesis of organometallic aluminum and zinc complexes, yielding dinuclear complexes with high efficiency. The structural elucidation of all compounds was accomplished through spectroscopic methods and validated by X-ray crystallography. Preliminary catalytic investigations into the coupling reaction of cyclohexene oxide and CO2 revealed that aluminum and zinc complexes catalyzed the selective formation of polyether and polycarbonate materials, respectively.

Development of Heterobimetallic Al/Mg Complexes for the Very Rapid Ring-Opening Polymerization of Lactides.

The successful architecture of active catalytic species with enhanced efficiencies is critical for the optimal exploitation of sustainable resources in industrially demanded processes. In this work, we describe the preparation of novel helical heterobimetallic Al/Mg-based complexes of the type [AlMe2(pbpamd-)MgR{κ1-O-(OC4H8O)}] [R = Et (1a), tBu (2a)] as potential catalysts. The design was performed through the sequential addition of the Al fragment to the ligand, followed by the Mg platform, resulting in a planar π-C2N2(sp2)-Al/Mg bridging core between metals. The new heterobimetallic species have been unambiguously characterized by single-crystal X-ray analysis. NOESY, DOSY, and EXSY NMR studies as well as density functional theory calculations corroborate both a rearrangement in solution to scorpionate complexes containing an unprecedented apical carbanion with a direct σ-C(sp3)-Al covalent bond named [{Mg(R)(pbpamd-) Al(Me)2}] [R = Et (1b), tBu (2b)] and an interconversion equilibrium between both isomers. We verified their utility and high efficiency as catalysts in the well-controlled ring-opening polymerization of the biorenewable l- and rac-lactide (LA) at 23 °C, reaching a remarkable turnover frequency value close to 25000 h-1 for rac-LA at this temperature and exerting a significant level of heteroselectivity (Pr = 0.80). Very interestingly, the kinetics demonstrate apparent first-order with respect to the catalyst and LA, which supports a synergic intramolecular cooperation between centers with electronic modulation among them.

Zinc-Catalyzed Hydroalkoxylation/Cyclization of Alkynyl Alcohols.

Despite the great interest in zinc catalysis for hydroelementation reactions, the use of zinc complexes as catalysts for the hydroalkoxylation of alkynyl alcohols has not been reported to date. Scorpionate zinc complexes have been successfully designed as precatalysts for the hydroalkoxylation reaction of alkynyl alcohols under mild reaction conditions. Zinc amide complex 8 has been shown to be an excellent precatalyst for the highly selective intramolecular hydroalkoxylation process to yield the corresponding exocyclic enol ethers. Kinetic studies have been performed and confirmed that reactions are first-order in [catalyst] and zero-order in [alkynyl alcohol]. NMR spectroscopy and X-ray diffraction analysis provided evidence for the formation of an alkynyl zinc compound which has been shown to be a key intermediate in the hydroalkoxylation process. On the basis of the experimental results, a catalytic cycle is proposed.

NNC-Scorpionate Zirconium-Based Bicomponent Systems for the Efficient CO2 Fixation into a Variety of Cyclic Carbonates.

Two new derivatives of the bis(3,5-dimethylpyrazol-1-yl)methane modified by introduction of organosilyl groups on the central carbon atom, one of which bearing a chiral fragment, have been easily prepared. We verified the potential utility of these compounds through the reaction with [Zr(NMe2)4] for the preparation of novel zirconium complexes in which an ancillary bis(pyrazol-1-yl)methanide acts as a robust monoanionic tridentate scorpionate in a κ3-NNC chelating mode, forming strained four-membered heterometallacycles. These κ3-NNC-scorpionate zirconium amides were investigated as catalysts in combination with tetra-n-butylammonium bromide as cocatalyst for CO2 fixation into five-membered cyclic carbonate products. The study has led to the development of an efficient zirconium-based bicomponent system for the selective cycloaddition reaction of CO2 with epoxides. Kinetics investigations confirmed apparent first-order dependence on the catalyst and cocatalyst concentrations. In addition, this system displays very broad substrate scope, including mono- and disubstituted substrates, as well as the challenging biorenewable terpene derived limonene oxide, under mild and solvent-free conditions.

Bimetallic Zinc Catalysts for Ring-Opening Copolymerization Processes.

Novel bimetallic zinc acetate complexes supported by heteroscorpionate ligands have been developed for the ring-opening copolymerization of cyclohexene oxide and CO2 and the terpolymerization of cyclohexene oxide, phthalic anhydride, and CO2. Heteroscorpionate ligands precursors L1-L3 were reacted with two equivalents of zinc acetate to afford the dinuclear zinc complexes [{Zn(κ3-bpzappe)}(µ-O2CCH3)3-{Zn(HO2CCH3)}] (1), [{Zn(κ3-bpzbdmape)}(µ-O2CCH3)3-{Zn(HO2CCH3)}] (2), and [{Zn(κ3-bpzbdeape)}(µ-O2CCH3)3{Zn(HO2CCH3)}] (3) in excellent yields. The molecular structure of these compounds was determined spectroscopically and confirmed by X-ray diffraction analysis. Zinc acetate complexes 1-3 were screened as catalysts for the copolymerization of cyclohexene oxide and CO2 to produce poly(cyclohexene)carbonate, and complex 3 was found to be the most active catalyst for this process in the absence of a cocatalyst. Furthermore, the terpolymerization of cyclohexene oxide, phthalic anhydride, and CO2 was studied using the combination of complex 3 and 4-dimethylaminopyridine as catalyst system yielding the corresponding polyester-polycarbonate materials.

Influence of the Counterion on the Synthesis of Cyclic Carbonates Catalyzed by Bifunctional Aluminum Complexes.

New bifunctional aluminum complexes have been prepared with the aim of studying the effect of a counterion on the synthesis of cyclic carbonates from epoxides and carbon dioxide (CO2). Neutral ligand 1 was used as a precursor to obtain four novel mesylate, chloride, bromide, and iodide zwitterionic NNO ligands (2-5). The reaction of these ligands with 1 or 2 equiv of AlR3 (R = Me, Et) allowed the synthesis of mono- and bimetallic bifunctional aluminum complexes [AlR2(κ2-mbpzappe)]X [X = Cl, R = Me (6), Et (7); X = Br, R = Me (8), Et (9); X = I, R = Me (10), Et (11)] and [{AlR2(κ2-mbpzappe)}(µ-O){AlR3}]X [X = MeSO3, R = Me (12), Et (13); X = Cl, R = Me (14), Et (15); X = Br, R = Me (16), Et (17); X = I, R = Me (18), Et (19)] via alkane elimination. These complexes were studied as catalysts for the synthesis of cyclic carbonates from epoxides and CO2. Iodide complex 11 showed to be the most active catalyst for terminal epoxides, whereas bromide complex 9 was found to be the optimal catalyst when internal epoxides were used, showing the importance of the nucleophile cocatalyst on the catalytic activity.

Study of the Coordination Modes of Hybrid NNCp Cyclopentadienyl/Scorpionate Ligands in Ir Compounds.

A new coordination mode for the hybrid scorpionate/cyclopentadienyl ligand bpzcp, [bpzcp = 2,2-bis(3,5-dimethylpyrazol-1-yl)-1,1-diphenylethylcyclopentadienyl] is observed in iridium complexes. The reaction of the lithium precursor, [Li(bpzcp)(THF)], with a range of [IrCl(diene)]2 compounds leads to an unprecedented binding mode of the hybrid scorpionate/cyclopentadienyl ligand as η5-Cp-coordinated and the formation of Ir(I) derivatives [Ir(η5-Cp-bpzcp)(η4-cod)] (1), [Ir(η5-Cp-bpzcp){η4-CH2═C(Me)C(Me)═CH2}] (2), [Ir(η5-Cp-bpzcp)(η2-coe)2] (3), and [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2] (4). The Ir(I) complex 4 reacts with CO or bromine to afford the compound [Ir(η5-Cp-bpzcp)(CO)2] (5) and the 18e- Ir(III) complex [Ir(κ-N-η5-Cp-bpzcpBr2)Br2] (6), respectively. Reaction of the iridium compounds (2-4) with CuI or [PdCl2(CH3CN)2] yields the heterobimetallic iridium-copper or iridium-palladium complexes [Ir(η5-Cp-bpzcp){η4-CH2═C(Me)C(Me)═CH2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (7), [Ir(η5-Cp-bpzcp)(η2-coe)2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (8), [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2}(µ-bpzcp){CuI(κ2-NN-bpzcp)}] (9), [Ir(η5-Cp-bpzcp)(coe)2}(µ-bpzcp){PdCl2(κ2-NN-bpzcp)}] (10), and [Ir(η5-Cp-bpzcp)(η2-CH2═CH2)2(µ-bpzcp){PdCl2(κ2-NN-bpzcp)}] (11). All products were characterized by spectroscopic methods and the X-ray crystal structures of 1, 2, 3, 4, and 6 were also established.

Organo-Aluminum and Zinc Acetamidinates: Preparation, Coordination Ability, and Ring-Opening Polymerization Processes of Cyclic Esters.

The reaction of the highly sterically demanding NNN'-heteroscorpionate protioligands pbptamd-H, tbptamd-H, and phbptamd-H (a) and the low sterically hindered analogs pbpamd-H, tbpamd-H, and phbpamd-H (b), with 1 equiv of AlR3 (R = Me, Et) proceed in high yields to give two families of complexes: the mononuclear dialkyl aluminum bidentate-acetamidinates [AlR2(κ2- N' N')] (κ2- N' N' = pbptamd, R = Me 1, Et 2; tbptamd, R = Me 3, Et 4; phbptamd, R = Me 5, Et 6) and the monodentate-acetamidinates [AlR2(κ2- NN')] (κ2- NN' = tbpamd, R = Me 7; phbpamd, R = Me 8, Et 9). In complexes 7-9, the presence of two possible CH-NH tautomers as low extended π-N-C-N'(sp2)-Al and high extended π-HN-C2-N'(sp2)-Al complexes, respectively, could be identified. Moreover, the reaction of aluminum dimethyls 7 and 8 with ZnMe2 afforded the isolation of the more stable scorpionate zinc monoalkyls [Zn(Me)(κ3- NNN')] ( NNN' = tbpamd 10 and phbpamd 11), through a very unusual ligand exchange process, involving a zinc-to-aluminum transmetalation of an alkyl group. The X-ray crystal structures of 1, 3, 7, and 8, as well as that of 11, confirmed unambiguously the different κ2-arrangements proposed for bi- or monodentate acetamidinate dialkyls 1-6 and 7-9, respectively, the presence of NH tautomer in 7 and 8, and a κ3- NNN' coordination in monoalkyl 11. Density functional theory calculations were used to explore the three different favored κ2-arrangements found in acetamidinate aluminum dialkyls 1-9, the relative stability of both CH-NH tautomers, and the ligand transfer reaction leading to the formation of κ3- NNN' zinc monoalkyls 10 and 11. Interestingly, dialkyls 1, 5, 7, and 8 can act as highly efficient single-component living initiators for the ring-opening polymerization of ε-caprolactone and rac-lactide in mild conditions after hours. These initiators efficiently mediated the immortal polymerization in the presence of excess of benzyl alcohol (up to 20 equiv), as evidenced by the narrow dispersity values and the good agreement between the experimental Mn values and monomer/benzyl alcohol ratios. In addition, the most sterically hindered initiator, 5, exhibits enhanced levels of heteroselectivity on the produced PLAs, reaching Ps values up to 0.70.

AAL Platform with a "De Facto" Standard Communication Interface (TICO): Training in Home Control in Special Education.

Framed within a long-term cooperation between university and special education teachers, training in alternative communication skills and home control was realized using the "TICO" interface, a communication panel editor extensively used in special education schools. From a technological view we follow AAL technology trends by integrating a successful interface in a heterogeneous services AAL platform, focusing on a functional view. Educationally, a very flexible interface in line with communication training allows dynamic adjustment of complexity, enhanced by an accessible mindset and virtual elements significance already in use, offers specific interaction feedback, adapts to the evolving needs and capacities and improves the personal autonomy and self-confidence of children at school and home. TICO-home-control was installed during the last school year in the library of a special education school to study adaptations and training strategies to enhance the autonomy opportunities of its pupils. The methodology involved a case study and structured and semi-structured observations. Five children, considered unable to use commercial home control systems were trained obtaining good results in enabling them to use an open home control system. Moreover this AAL platform has proved efficient in training children in previous cognitive steps like virtual representation and cause-effect interaction.

Synthesis of Cyclic Carbonates Catalysed by Aluminium Heteroscorpionate Complexes.

New aluminium scorpionate based complexes have been prepared and used for the synthesis of cyclic carbonates from epoxides and carbon dioxide. Bimetallic aluminium(heteroscorpionate) complexes 9-14 were synthesised in very high yields. The single-crystal X-ray structures of 12 and 13 confirm an asymmetric κ(2)-NO-µ-O arrangement in a dinuclear molecular disposition. These bimetallic aluminium complexes were investigated as catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide in the presence of ammonium salts. Under the optimal reaction conditions, complex 9 in combination with tetrabutylammonium bromide acts as a very efficient catalyst system for the conversion of both monosubstituted and internal epoxides into the corresponding cyclic carbonates showing broad substrate scope. Complex 9 and tetrabutylammonium bromide is the second most efficient aluminium-based catalyst system for the reaction of internal epoxides with carbon dioxide. A kinetic study has been carried out and showed that the reactions were first order in complex 9 and tetrabutylammonium bromide concentrations. Based on the kinetic study, a catalytic cycle is proposed.

Progress of patients hospitalized with acute heart failure treated with empagliflozin.

Aim: To describe the epidemiological, clinical and laboratory characteristics and clinical progress of patients hospitalized with heart failure (HF) who started treatment with empagliflozin before discharge. Methods: We performed a retrospective observational study of patients aged ≥18 years admitted to the Internal Medicine Department of University Hospital Jaen, Jaen, Spain with acute HF between 1 May 2022 and 31 May 2023. Patients had to have a life expectancy of ≥1 year and have started treatment with empagliflozin during admission. Results: We included 112 patients (mean age, 85.2 ± 6.5 years; 67.9% women; 35.7 and 31.3% in NYHA functional classes III and IV; 73.2% with HF and preserved ejection fraction). Before admission, 80.4% were taking loop diuretics, 70.6% renin-angiotensin-aldosterone system inhibitors, 49.1% betablockers and 25% mineralocorticoid receptor antagonists. At admission, 94.6% were taking furosemide (15.2% at high doses, 36.6% at intermediate doses). The dose of furosemide was reduced at initiation of empagliflozin. At the end of follow-up, 13.4% of patients had died, 93.8% of the survivors continued treatment with empagliflozin and 26.8% had attended the emergency department with signs and symptoms of HF. Conclusion: Introduction of empagliflozin before discharge from hospital in patients admitted with HF made it possible to reduce the dose of diuretics during admission. The frequency of complications was as expected, and treatment was largely maintained.

Evaluation of heteroscorpionate ligands as scaffolds for the generation of Ruthenium(II) metallodrugs in breast cancer therapy.

The modular synthesis of the heteroscorpionate core is explored as a tool for the rapid development of ruthenium-based therapeutic agents. Starting with a series of structurally diverse alcohol-NN ligands, a family of heteroscorpionate-based ruthenium derivatives was synthesized, characterized, and evaluated as an alternative to platinum therapy for breast cancer therapy. In vitro, the antitumoral activity of the novel derivatives was assessed in a series of breast cancer cell lines using UNICAM-1 and cisplatin as metallodrug control. Through this approach, a bimetallic heteroscorpionate-based metallodrug (RUSCO-2) was identified as the lead compound of the series with an IC50 value range as low as 3-5 µM. Notably, RUSCO-2 was found to be highly cytotoxic in TNBC cell lines, suggesting a mode of action independent of the receptor status of the cells. As a proof of concept and taking advantage of the luminescent properties of one of the complexes obtained, uptake was monitored in human breast cancer MCF7 cell lines by fluorescence lifetime imaging microscopy (FLIM) to reveal that the compound is evenly distributed in the cytoplasm and that the incorporation of the heteroscorpionate ligand protects it from aqueous processes, conversion in another entity, or the loss of the chloride group. Finally, ROS studies were conducted, lipophilicity was estimated, the chloride/water exchange was studied, and stability studies in simulated biological media were carried out to propose structure-activity relationships.

Heteroscorpionate magnesium alkyls bearing unprecedented apical σ-C(sp3)-mg bonds: heteroselective ring-opening polymerization of rac-lactide.

The previously described reaction of the low sterically hindered heteroscorpionate lithium acetamidinates [Li(κ(3)-pbpamd)(THF)] and [Li(κ(3)-tbpamd)(THF)] with a series of commercially available Grignard reagents RMgCl in an equimolecular ratio yielded the magnesium monoalkyls [Mg(R)(κ(3)-NNN)] (NNN = pbpamd, R = CH2SiMe3, Et (1), Bn (2); NNN = tbpamd, R = CH2SiMe3, Et (3), Bn (4)). However, subsequent reaction of these monoalkyls [Mg(R)(κ(3)-NNN)] with two additional equivalents of the same RMgCl in tetrahydrofuran gave rise to dinuclear dialkyls of the type [RMg(κ(3)-N,N,N;κ(2)-C,N)MgR(thf)] (κ(3)-N,N,N;κ(2)-C,N = pbpamd(-), R = CH2SiMe3 (5), Et (6); κ(3)-N,N,N;κ(2)-C,N = tbpamd(-), R = CH2SiMe3 (7), Et (8)). Furthermore, when the reaction was carried out in a mixture of tetrahydrofuran/dioxane with the same stoichiometry, a new family of tetranuclear tetraalkyl magnesium complexes [{RMg(κ(3)-N,N,N;κ(2)-C,N)MgR}2{µ-O,O-(C4H8)}] (κ(3)-N,N,N;κ(2)-C,N = pbpamd(-), R = CH2SiMe3 (9), Et (10), Bn (11); κ(3)-N,N,N;κ(2)-C,N = tbpamd(-), R = CH2SiMe3 (12), Et (13), Bn (14)) was obtained. In both families, an apical methine C-H activation process on the heteroscorpionate takes place. The single-crystal X-ray structures of 4, 8, 9, and 12 confirm the nuclearity of each family, with 4-coordinative arrangements for all magnesium atoms. More importantly, the presence in the di- and tetranuclear complexes of unprecedented apical carbanions with a direct σ-C(sp(3))-Mg covalent bond, and as a result, the existence of stereogenic magnesium centers, have been unambiguously confirmed. Interestingly, the dinuclear dialkyls 5 and 7, as well as the tetranuclear tetraalkyls 9, 10, and 12, can act as highly efficient single-component living initiators for the ring-opening polymerization of ε-caprolactone and lactides. Lactide (LA) polymerizations afforded polylactide (PLA) materials with medium molecular weights in only a few minutes even at 20 °C for L-LA and in a few hours at 50 °C for rac-LA propagations. More importantly, microstructural analysis of the poly(rac-lactide) materials revealed that the tetranuclear tetra-alkyl 12 exerts enhanced levels of heteroselectivity on the PLAs under mild conditions, with Ps values up to 0.78.

Very efficient organo-zinc scorpionates for CO2 fixation into a variety of cyclic carbonates: synthesis, coordination ability and catalytic studies.

The fixation of CO2 mediated by metal-based catalysts for the production of organic molecules of industrial interest such as cyclic carbonates is urgently required under green and eco-friendly conditions. Herein, we describe the easy preparation of sterically demanding scorpionate ligands bearing different electron-withdrawing groups, and their coordination ability for the preparation of robust zinc-based mononuclear complexes of the type [ZnMe(κ3-NNN')] (4-6). These complexes, in combination with co-catalysts comprising larger ionic radius-based halides such as tetra-n-butylammonium, functioned as very active and selective catalysts for CO2 fixation into five-membered cyclic carbonates. These studies have led to the development of sustainable, inexpensive, and low-toxicity systems formed by 4-5 and Bu4NBr for the cycloaddition of CO2 into epoxides under very mild and solvent-free conditions, reaching very good to excellent conversions (TOF = 260 h-1). Moreover, these bicomponent systems show a broad substrate scope and functional group tolerance, including mono- and di-substituted epoxides, as well as bio-renewable diepoxides. Very interestingly, these are the first zinc-based systems reported to date for the successful transformation of the very challenging tri-substituted terpene-derived cis/trans-limonene oxide, whose reaction proceeds with high stereoselectivity to the formation of the bicyclic trans-limonene carbonate. Additionally, these bicomponents can be efficiently used up to six times without significant loss of activity. Kinetic investigations confirmed that the reaction shows an apparent first-order dependence on the catalyst and co-catalyst concentrations, which indicates an intramolecular monometallic mechanism.

One-pot terpolymerization of CHO, CO2 and L-lactide using chloride indium catalysts.

Ring-opening copolymerization reactions of epoxides, carbon dioxide and cyclic esters to produce copolymers is a promising strategy to prepare CO2-based polymeric materials. In this contribution, bimetallic chloride indium complexes have been developed as catalysts for the copolymerization processes of cyclohexene oxide, carbon dioxide and L-lactide under mild reaction conditions. The catalysts displayed good catalytic activity and excellent selectivity towards the preparation of poly(cyclohexene carbonate) (PCHC) at one bar CO2 pressure in the absence of a co-catalyst. Additionally, polyester-polycarbonate copolymers poly(lactide-co-cyclohexene carbonate) (PLA-co-PCHC) were obtained via an one-pot one-step route without the use of a co-catalyst. The degree of incorporation of carbon dioxide can be easily modulated by changing the CO2 pressure and the monomer feed, resulting in copolymers with different thermal properties.

Unexpected luminescence of non-conjugated biomass-based polymers: new approach in photothermal imaging.

Population growth, depletion of world resources and persistent toxic chemical production underline the need to seek new smart materials from inexpensive, biodegradable, and renewable feedstocks. Hence, "metal-free" ring-opening copolymerization to convert biomass carvone-based monomers into non-conventional luminescent biopolymers is considered a sustainable approach to achieve these goals. The non-conventional emission was studied in terms of steady-state and time-resolved spectroscopy in order to unravel the structure-properties for different carvone-based copolymers. The results highlighted the importance of the final copolymer folding structure as well as its environment in luminescent behavior (cluster-triggered emission). In all cases, their luminescent behavior is sensitive to small temperature fluctuations (where the minimum detected temperature is Tm ∼ 2 °C and relative sensitivity is Sr ∼ 6% °C) even at the microscopic scale, which endows these materials a great potential as thermosensitive smart polymers for photothermal imaging.

Synthesis, characterization, and antibacterial activities of a heteroscorpionate derivative platinum complex against methicillin-resistant Staphylococcus aureus.

Staphylococcus aureus is one of the species with the greatest clinical importance and greatest impact on public health. In fact, methicillin-resistant S. aureus (MRSA) is considered a pandemic pathogen, being essential to develop effective medicines and combat its rapid spread. This study aimed to foster the translation of clinical research outcomes based on metallodrugs into clinical practice for the treatment of MRSA. Bearing in mind the promising anti-Gram-positive effect of the heteroscorpionate ligand 1,1'-(2-(4-isopropylphenyl)ethane-1,1-diyl)bis(3,5-dimethyl-1H-pyrazole) (2P), we propose the coordination of this compound to platinum as a clinical strategy with the ultimate aim of overcoming resistance in the treatment of MRSA. Therefore, the novel metallodrug 2P-Pt were synthetized, fully characterized and its antibacterial effect against the planktonic and biofilm state of S. aureus evaluated. In this sense, three different strains of S. aureus were studied, one collection strain of S. aureus sensitive to methicillin and two clinical MRSA strains. To appraise the antibacterial activity, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), minimum biofilm inhibitory concentration (MBIC), and minimum biofilm eradication concentration (MBEC) were determined. Moreover, successful outcomes on the development of biofilm in a wound-like medium were obtained. The mechanism of action for 2P-Pt was proposed by measuring the MIC and MBC with EDTA (cation mediated mechanism) and DMSO (exogenous oxidative stress mechanism). Moreover, to shed light on the plausible antistaphylococcal mechanism of this novel platinum agent, additional experiments using transmission electron microscopy were carried out. 2P-Pt inhibited the growth and eradicated the three strains evaluated in the planktonic state. Another point worth stressing is the inhibition in the growth of MRSA biofilm even in a wounded medium. The results of this work support this novel agent as a promising therapeutic alternative for preventing infections caused by MRSA.

Assessment of Poorly Compactable Sands by Recycling and Recompaction: Experimental Program and Packing Particle Analysis.

Compaction is a common ground improvement technique based on the densification of soils for an energy level and optimum water content, mainly influenced by the particle size and curve gradation. Poorly compactable sands, characterized as cohesionless, fine and uniformly graded, are a challenge for earthworks since compaction is not effective due to the lack of a larger range of particle sizes to infill the voids and the compaction energy is not relevant either. These characteristics are common to other materials, i.e., desert sand, industrial or mining by-products or quarry fines, which are mostly discarded to landfill and replaced by proper soils, causing serious environmental issues. To enlarge the technical feasibilities of poorly compactable sands, reducing construction waste and raw material consumption, a mechanical stabilization, based on a repetitive series of recycling and recompaction without binder, is experimentally explored. The behavior observed is also analyzed from reported correlations and a packing particle approach, attending to densification stage, saturation degree, recompaction series, coordination number and packing density. The improvement achieved is moderate and dependent on the cycles applied, showing a characteristic repetitive pattern in the compaction curve, and approaching the estimated minimum void ratio and the theoretical maximum packing possibilities without degradation of the material.

Phase Angle and Handgrip Strength as a Predictor of Disease-Related Malnutrition in Admitted Patients: 12-Month Mortality.

Background: Phase Angle (PhA) value measured by bioelectrical impedance analysis (BIA) could be considered a good marker of the patient's cell mass and cellular damage. Various studies have shown that the value of PhA is associated with an increased nutritional risk in several pathologies. However, not many studies have focused on the use of PhA as a screening tool in admitted patients. The aim of this study is to evaluate the prognostic value of PhA to determine disease-related malnutrition (DRM) and the risk that this entails for mortality and length of stay (LOS). Methods: 570 patients admitted to the hospital for different causes were included in this retrospective observational study. Patients' nutritional risk was assessed by screening tests such as the Malnutrition Universal Screening tool (MUST) and Subjective Global Assessment (SGA), in addition to non-invasive functional techniques, such as BIA and handgrip strength (HGS), 24−48 h after admission. After performing an SGA as the gold standard to assess malnutrition, PhA and SPhA values were used to determine DRM. Furthermore, both samples: malnutrition status (MS) and non-malnutrition status (NMS) were compared, with SphA-Malnutrition corresponding to a diagnosis of malnutrition. Statistical analysis of the sample was conducted with JAMOVI version 2.2.2. Results: Patients with MS had lower PhA and SPhA than patients with NMS (p < 0.001). The ROC curve analysis (AUC = 0.81) showed a cut-off point for MS for PhA = 5.4° (sensitivity 77.51% and specificity 74.07%) and AUC = 0.776 with a cut-off point for SPhA = −0.3 (sensitivity 81.74% and specificity 63.53%). Handgrip strength (HGS) was also observed to be a good predictor in hospitalized patients. Carrying out a comparative analysis between MS and NMS, length of stay (LOS) was 9.0 days in MS vs. 5.0 days in NMS patients (OR 1.07 (1.04−1.09, p < 0.001)). A low SPhA-malnutrition value (SPhA < −0.3) was significantly associated with a higher mortality hazards ratio (HR 7.87, 95% CI 2.56−24.24, p < 0.001). Conclusion: PhA, SPhA and HGS are shown to be good prognostic markers of DRM, LOS and mortality and could therefore be useful screening tools to complement the nutritional assessment of admitted patients.

Synthesis of Nonisocyanate Poly(hydroxy)urethanes from Bis(cyclic carbonates) and Polyamines.

Nonisocyanate polyurethane materials with pending alcohol groups in the polymeric chain were synthesized by polyaddition reaction of bis(cyclic carbonates) onto diamines. For the platform molecule, 1,4-butanediol bis(glycidyl ether carbonate) (BGBC, 1) was used. The polyaddition reaction of 1 onto a wide range of diamines with different electronic and physical properties was explored. All PHUs were obtained quantitatively after 16 h at 80 °C temperature in MeCN as solvent. The low nucleophilicity of L-lysine has proven unable to ring-open the cyclic carbonate and, thus, no reaction occurred. The addition of DBU or TBD as the catalyst was tested and allows the obtention of the desired PHU. However, the presence of strong bases also led to the formation of polyurea fragments in the new PHU. The different poly(hydroxyurethane) materials were characterized using a wide range of spectroscopic techniques such as NMR, IR, MALDI-ToF, and using GPC studies. The thermal properties of the NIPUs were investigated by DSC and TGA analyses. Moreover, reactions employing different monomer ratios were performed, obtaining novel hydroxycarbamate compounds. Finally, sequential and one-pot experiments were also carried out to synthesize the PHUs polymers in one-step reaction.