L-Cysteine-Catalysed Hydration of Activated Alkynes.

Hydration reactions consist of the introduction of a molecule of water into a chemical compound and are particularly useful to transform alkynes into carbonyls, which are strategic intermediates in the synthesis of a plethora of compounds. Herein we demonstrate that L-cysteine can catalyse the hydration of activated alkynes in a very effective and fully regioselective manner to access important building blocks in synthetic chemistry such as β-ketosulfones, amides and esters, in aqueous media. The mild reaction conditions facilitated the integration with enzyme catalysis to access chiral β-hydroxy sulfones from the corresponding alkynes in a one-pot cascade process in good yields and excellent enantiomeric ratios.

BioLindlar Catalyst: Ene-Reductase-Promoted Selective Bioreduction of Cyanoalkynes to Give (Z)-Cyanoalkenes.

The direct synthesis of alkenes from alkynes usually requires the use of transition-metal catalysts. Unfortunately, efficient biocatalytic alternatives for this transformation have yet to be discovered. Herein, the selective bioreduction of electron-deficient alkynes to alkenes catalysed by ene-reductases (EREDs) is described.

Clinical Course, Nosocomial, and Opportunistic Infections Among Kidney Transplant Recipients with COVID-19: A Retrospective Single Center Study.

Background: We report the results of an observational study, analyzing the clinical course of kidney transplant patients hospitalized for COVID-19 and comparing it with a control to determine if outcomes, nosocomial, and opportunistic infections were different between groups.

Methods: An observational, retrospective, case-control, single-center study, including a group of kidney transplant adults diagnosed with COVID-19, from March 2020 to April 2022. Transplant patients hospitalized for COVID-19 comprised the cases.

Improving the sustainability of heterogeneous Fenton-based methods for micropollutant abatement by electrochemical coupling.

Advanced oxidation processes such as Fenton reaction-based processes have attracted great interest in recent years as a promising alternative for the removal of persistent pollutants in wastewater. The use of nanocatalysts in advanced oxidation processes overcomes the limitations of homogeneous Fenton processes, where acidic pH values are required, and a large amount of sludge is generated after treatment. Aiming at maximizing the catalytic potential of the process, different configurations include coupling photocatalysis or electrochemistry to Fenton reactions.

Synthesis of Optically Active - and -Chlorohydrins through a Bienzymatic Reductive Cascade.

A bienzymatic cascade has been designed and optimized to obtain enantiopure chlorohydrins starting from the corresponding 1-aryl-2-chlorobut-2-en-1-ones. For the synthesis of these α-chloroenones, a two-step sequence was developed consisting of the allylation of the corresponding aldehyde with 3-dichloroprop-1-ene, followed by oxidation and further isomerization. The selective cooperative catalytic system involving ene-reductases (EREDs) and alcohol dehydrogenases (ADHs) afforded the desired optically active chlorohydrins under mild reaction conditions in excellent conversions (up to >99%) and selectivities (up to >99:1 diastereomeric ratio (dr), >99% enantiomeric excess ()).

Exploiting the Potential of Supported Magnetic Nanomaterials as Fenton-Like Catalysts for Environmental Applications.

In recent years, the application of magnetic nanoparticles as alternative catalysts to conventional Fenton processes has been investigated for the removal of emerging pollutants in wastewater. While this type of catalyst reduces the release of iron hydroxides with the treated effluent, it also presents certain disadvantages, such as slower reaction kinetics associated with the availability of iron and mass transfer limitations. To overcome these drawbacks, the functionalization of the nanocatalyst surface through the addition of coatings such as polyacrylic acid (PAA) and their immobilization on a mesoporous silica matrix (SBA15) can be factors that improve the dispersion and stability of the nanoparticles.

Systemic sclerosis and microscopic polyangiitis after systemic exposure to silicone.

The relationship between silicon breast implants (SBIs) and autoimmune/inflammatory syndrome induced by adjuvants (ASIA) has been extensively analysed, with discordant results. We present a 45-year-old woman with confirmed systemic exposure to SBI who developed systemic sclerosis (SSc) followed by anti-neutrophil cytoplasmic antibody anti-myeloperoxidase vasculitis with renopulmonary syndrome. The novelty of our case is, first, confirmation of systemic exposure to SBI and, second, chronologic development of not one, but two severe autoimmune diseases.

Reusable FeO/SBA15 Nanocomposite as an Efficient Photo-Fenton Catalyst for the Removal of Sulfamethoxazole and Orange II.

Today, the presence of recalcitrant pollutants in wastewater, such as pharmaceuticals or other organic compounds, is one of the main obstacles to the widespread implementation of water reuse. In this context, the development of innovative processes for their removal becomes necessary to guarantee effluent quality. This work presents the potentiality of magnetic nanoparticles immobilized on SBA-15 mesoporous silica as Fenton and photo-Fenton catalysts under visible light irradiation.

Polymeric Ionic Liquids Derived from -Valine for the Preparation of Highly Selective Silica-Supported Stationary Phases in Gas Chromatography.

A series of silica-supported polymeric ionic liquid (PIL)-based stationary phases derived from a vinylic -valine ionic liquid monomer and divinylbenzene (DVB) as the crosslinking agent have been prepared and studied as gas chromatographic stationary phases. These coated gas chromatographic columns exhibited good thermal stabilities (230-300 °C) and high efficiencies (1700-2700 plates/m), and were characterized using a linear solvation parameter model in order to understand the effects of the amount of DVB on the features of the resulting composite systems. Their retention behavior and separation efficiencies were demonstrated using the Grob test.