Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Chapter 10: Chalcogenides and Non-oxides

Comprehensive Inorganic Chemistry II reviews and examines topics of relevance to today’s inorganic chemists. Covering more interdisciplinary and high impact areas, Comprehensive Inorganic Chemistry II includes biological inorganic chemistry, solid state chemistry, materials chemistry, and nanoscience. The work is designed to follow on, with a different viewpoint and format, from our 1973 work, Comprehensive Inorganic Chemistry, edited by Bailar, Emeléus, Nyholm, and Trotman-Dickenson, which has received over 2,000 citations. The new work will also complement other recent Elsevier works in this area, Comprehensive Coordination Chemistry and Comprehensive Organometallic Chemistry, to form a trio of works covering the whole of modern inorganic chemistry. Chapters are designed to provide a valuable, long-standing scientific resource for both advanced students new to an area and researchers who need further background or answers to a particular problem on the elements, their compounds, or applications. Chapters are written by teams of leading experts, under the guidance of the Volume Editors and the Editors-in-Chief. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource for information in the field. The chapters will not provide basic data on the elements, which is available from many sources (and the original work), but instead concentrate on applications of the elements and their compounds.https://nsuworks.nova.edu/cnso_chemphys_facbooks/1010/thumbnail.jp

Discovery and Crystallographic Challenges of Diamond-Like Semiconductors with Attractive Physicochemical Properties

Diamond-like semiconductors (DLSs) adopt crystal structures that can be considered as superstructures of diamond, either the cubic or hexagonal form. Although diamond-like structures are seemingly simple, these materials exhibit a number of crystallographic challenges and opportunities. Solving complex problems such as delineating cation patterns, differentiating polymorphs, discerning isoelectronic elements, and locating dopants/elemental substituents within ternary I-III-VI2 and quaternary I2-II-IV-VI4 DLSs is important to garner a fundamental understanding of structure-property relationships to improve these materials for potential applications. The attractive electrical, optical and magnetic properties of DLSs can be tuned through compositional changes, which often result in subtle structural variations that are sometimes only detectable through careful analysis of high-quality diffraction data. The assortment of structure types that have been observed among ternary and quaternary DLSs can be categorized by the closest-packed arrangement of the anions. Within each kind of closest-packed anion array, cations can display several unique ordering patterns within the tetrahedral holes, as found in the hexagonally derived wurtzstannite (Pmn21), wurtzkesterite (Pn) and lithium cobalt (II) silicate (Pna21) structure types. X-ray diffraction patterns of such materials can be strikingly similar and are difficult to distinguish in many instances. Concomitant with structural changes, marked effects on the observed physicochemical properties can be observed in polymorphs within a single composition. In the cases where the ions making up the formulae are isoelectronic, or nearly isoelectronic, challenges arise in discriminating between the ions using X-ray diffraction. Furthermore, the properties of these materials can be altered by partially replacing one ion in the lattice with another through a process of doping/substitution. Understanding the structural implications of these alterations on the resulting properties can benefit the future design of DLSs

The Impact of Three New Quaternary Sulfides on the Current Predictive Tools for Structure and Composition of Diamond-Like Materials

Iron-containing diamond-like materials Ag2FeSiS4, Li2FeSnS4, and Li2FeGeS4 were synthesized for the first time via high-temperature, solid-state synthesis and found to adopt the wurtz–kesterite structure, crystallizing in the noncentrosymmetric space group Pn. These materials are considered in the broader context of design principles for new cubic- and hexagonal-derived diamond-like materials. All three of these new compounds violate Pauling’s radius ratio rule and Pfitzner’s tetrahedral volume theory. An evaluation of the adherence of over 40 published quaternary diamond-like structures to Pauling’s radius ratio rule and Pfitzner’s tetrahedral volume theory reveals that tetrahedral structures can often be generated even though these ideals are violated. To assess the radius ratios in diamond-like structures, an appropriate radii set must be selected. Accordingly, five radii sets have been investigated for accuracy in predicting metal–sulfur bond distances in diamond-like materials. Furthermore, a crystal radius of 1.63 Å for four-coordinate S2− has been calculated using the metal–sulfur bond lengths of quaternary diamond-like materials and is proposed as an addition to the popular Shannon radii set

Optical Nonlinearity in Cu2CdSnS4 and α/β-Cu2ZnSiS4: Diamond-like Semiconductors with High Laser-Damage Thresholds

Cu2CdSnS4 and α/β-Cu2ZnSiS4 meet several criteria for promising nonlinear optical materials for use in the infrared (IR) region. Both are air-stable, crystallize in noncentrosymmetric space groups, and possess high thermal stabilities. Cu2CdSnS4 and α/β-Cu2ZnSiS4 display wide ranges of optical transparency, 1.4–25 and 0.7–25 μm, respectively, and have relatively large second-order nonlinearity as well as phase matchability for wide regions in the IR. The laser-damage threshold (LDT) for Cu2CdSnS4 is 0.2 GW/cm2, whereas α/β-Cu2ZnSiS4 has a LDT of 2.0 GW/cm2 for picosecond near-IR excitation. Both compounds also exhibit efficient third-order nonlinearity. Electronic structure calculations provide insight into the variation in properties

Optical Nonlinearity in Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄: Diamond-like Semiconductors with High Laser-Damage Thresholds

Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄ meet several criteria for promising nonlinear optical materials for use in the infrared (IR) region. Both are air-stable, crystallize in noncentrosymmetric space groups, and possess high thermal stabilities. Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄ display wide ranges of optical transparency, 1.4–25 and 0.7–25 μm, respectively, and have relatively large second-order nonlinearity as well as phase matchability for wide regions in the IR. The laser-damage threshold (LDT) for Cu₂CdSnS₄ is 0.2 GW/cm², whereas α/β-Cu₂ZnSiS₄ has a LDT of 2.0 GW/cm² for picosecond near-IR excitation. Both compounds also exhibit efficient third-order nonlinearity. Electronic structure calculations provide insight into the variation in properties

Optical Nonlinearity in Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄: Diamond-like Semiconductors with High Laser-Damage Thresholds

Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄ meet several criteria for promising nonlinear optical materials for use in the infrared (IR) region. Both are air-stable, crystallize in noncentrosymmetric space groups, and possess high thermal stabilities. Cu₂CdSnS₄ and α/β-Cu₂ZnSiS₄ display wide ranges of optical transparency, 1.4–25 and 0.7–25 μm, respectively, and have relatively large second-order nonlinearity as well as phase matchability for wide regions in the IR. The laser-damage threshold (LDT) for Cu₂CdSnS₄ is 0.2 GW/cm², whereas α/β-Cu₂ZnSiS₄ has a LDT of 2.0 GW/cm² for picosecond near-IR excitation. Both compounds also exhibit efficient third-order nonlinearity. Electronic structure calculations provide insight into the variation in properties