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OBJECTIVES: People with HIV are at increased risk for metabolic dysfunction-associated steatohepatitis (MASH). Although sex differences are documented in the general population, their role in the context of HIV is less understood. METHODS: This was a multicentre cohort study including people with HIV without viral hepatitis coinfection. A FibroScan-AST (FAST) score >0.35 was used to diagnose MASH with significant liver fibrosis (stage F2-F4). We investigated sex-based differences in MASH trends as a function of age using a segmented linear mixed-effects model. Random effects accounted for clustering by the four sites. Adjusted models included ethnicity, diabetes, hypertension, and detectable HIV viral load. RESULTS: We included 1472 people with HIV (25% women). At baseline, the prevalence of MASH with fibrosis by FAST score was lower in women than in men (4.8% vs. 9.2%, p = 0.008). Based on the adjusted model, male sex (+0.034; p = 0.04), age per year (+0.003; p = 0.05), detectable HIV viral load (+0.034; p = 0.02), and hypertension (+0.03; p = 0.01) were positively associated with MASH with fibrosis. Although men exhibited generally higher FAST scores, FAST scores increased in women during the critical biological age of presumed perimenopause to menopause (between 40 and 50 years), reaching levels similar to those in men by the age of 55 years. CONCLUSION: Despite women with HIV having a lower prevalence of MASH with fibrosis than men, they exhibit an acceleration in FAST score increase around the perimenopausal age. Future studies should target adequate consideration of sex differences in clinical investigation of metabolic dysfunction-associated steatotic liver disease to fill current gaps and implement precision medicine for people with HIV.
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The UN Sustainable Development Goals (SDGs) provide a framework for addressing some of the most pressing global challenges, from rising inequalities to economic growth and environmental impact. Chemistry is relevant to these issues and this Editorial reviews the contributions in the chemistry community in Switzerland.
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The stability of hybrid organic-inorganic halide perovskite semiconductors remains a significant obstacle to their application in photovoltaics. To this end, the use of low-dimensional (LD) perovskites, which incorporate hydrophobic organic moieties, provides an effective strategy to improve their stability, yet often at the expense of their performance. To address this limitation, supramolecular engineering of noncovalent interactions between organic and inorganic components has shown potential by relying on hydrogen bonding and conventional van der Waals interactions. Here, the capacity to access novel LD perovskite structures that uniquely assemble through unorthodox S-mediated interactions is explored by incorporating benzothiadiazole-based moieties. The formation of S-mediated LD structures is demonstrated, including one-dimensional (1D) and layered two-dimensional (2D) perovskite phases assembled via chalcogen bonding and S-π interactions, through a combination of techniques, such as single crystal and thin film X-ray diffraction, as well as solid-state NMR spectroscopy, complemented by molecular dynamics simulations, density functional theory calculations, and optoelectronic characterization, revealing superior conductivities of S-mediated LD perovskites. The resulting materials are applied in n-i-p and p-i-n perovskite solar cells, demonstrating enhancements in performance and operational stability that reveal a versatile supramolecular strategy in photovoltaics.
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The understanding of mixed ionic-electronic conductivity in hybrid perovskites has enabled major advances in the development of optoelectronic devices based on this class of materials. While recent investigations revealed the potential of using dimensionality effects for various applications, the implication of this strategy on mixed conductivity is yet to be established. Here, we present a systematic analysis of mixed conduction in layered (2D) hybrid halide perovskite films based on 1,4-phenylenedimethylammonium (PDMA) and benzylammonium (BzA) organic spacers in (PDMA)PbI4 and (BzA)2PbI4 compositions, forming representative Dion-Jacobson (DJ) and Ruddleson-Popper (RP) phases, respectively. Electrochemical measurements of charge transport parallel to the layered structure reveal mixed ionic-electronic conduction with electronic transport mediated by electron holes in both DJ and RP phases. In comparison to the 3D perovskites, larger activation energies for both ionic and electronic conductivities are observed which result in lower absolute values. While the layered perovskites still allow for a relatively efficient exchange of iodine with the gas phase, the lower change of conductivity on the variation of the iodine partial pressure compared with 3D perovskites is consistent with the exchange affecting only a fraction of the film, with implications for the encapsulating efficacy of these materials. We complement the analysis with a demonstration of the superior thermal stability of DJ structures compared to their RP counterparts. This can guide future explorations of dimensionality and composition to control the transport and stabilization properties of 2D perovskite films.
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Hybrid metal halide perovskites have demonstrated remarkable performances in modern photovoltaics, although their stabilities remain limited. We assess the capacity to advance their properties by relying on interfacial modulators featuring helical chirality based on P,M-(1-methylene-3-methyl-imidazolium)[6]helicene iodides. We investigate their characteristics, demonstrating comparable charge injection for enantiomers and the racemic mixture. Overall, they maintain the resulting photovoltaic performance while improving operational stability, challenging the role of helical chirality in the interfacial modulation of perovskite solar cells.
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Hybrid halide perovskites are attractive candidates for resistive switching memories in neuromorphic computing applications due to their mixed ionic-electronic conductivity. Moreover, their exceptional optoelectronic characteristics make them effective as semiconductors in photovoltaics, opening perspectives for self-powered memory elements. These devices, however, remain unexploited, which is related to the variability in their switching characteristics, weak endurance, and retention, which limit their performance and practical use. To address this challenge, we applied low-dimensional perovskite capping layers onto 3D mixed halide perovskites using two perfluoroarene organic cations, namely (perfluorobenzyl)ammonium and (perfluoro-1,4-phenylene)dimethylammonium iodide, forming Ruddlesden-Popper and Dion-Jacobson 2D perovskite phases, respectively. The corresponding mixed-dimensional perovskite heterostructures were used to fabricate resistive switching memories based on perovskite solar cell architectures, showing that the devices based on perfluoroarene heterostructures exhibited enhanced performance and stability in inert and ambient air atmosphere. This opens perspectives for multidimensional perovskite materials in durable self-powered memory elements in the future.
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Perovskite solar cells have demonstrated exceptional development over the past decade, but their stability remains a challenge toward the application of this technology. Several strategies have been used to address this, and the use of host-guest complexation has recently attracted more interest. However, this approach has primarily been exploited in conventional perovskite solar cells based on n-i-p architectures, while its use in inverted p-i-n devices remains unexplored. Herein, we employ representative crown ether, dibenzo-24-crown-8, for interfacial host-guest complexation in inverted perovskite solar cells based on methylammonium and methylammonium-free formamidinium-cesium halide perovskite compositions. Upon post-treatment of the perovskite films, we observed nanostructures on the surface that were associated with the reduced amount of trap states at the interface with the electron transport layer. As a result, we demonstrate improved efficiencies and operational stabilities following ISOS-D-2I and ISOS-L-2I protocols, demonstrating the viability of this approach to advance device stability.
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OBJECTIVE: People with HIV (PWH) have high risk of liver fibrosis. We investigated the effect of weight gain and metabolic dysfunction-associated steatotic liver disease (MASLD) on liver fibrosis dynamics. DESIGN: Multicenter cohort study. METHODS: Fibrosis progression was defined as development of significant fibrosis [liver stiffness measurement (LSM) ≥8âkPa], or transition to cirrhosis (LSM ≥13âkPa), for those with significant fibrosis at baseline. Fibrosis regression was defined as transition to LSM less than 8âkPa, or to LSM less than 13âkPa for those with cirrhosis at baseline. MASLD was defined as hepatic steatosis (controlled attenuation parameter >248âdB/m) with at least one metabolic abnormality. A continuous-time multistate Markov model was used to describe transitions across fibrosis states. RESULTS: Among 1183 PWH included from three centers (25.2% with viral hepatitis coinfection), baseline prevalence of significant fibrosis and MASLD was 14.4 and 46.8%, respectively. During a median follow-up of 2.5âyears (interquartile range 1.9-3.5), the incidence rate of fibrosis progression and regression was 2.8 [95% confidence interval (CI) 2.3-3.4] and 2.2 (95% CI 1.9-2.6) per 100 person-years, respectively. In Markov model, weight gain increased the odds of fibrosis progression [odds ratio (OR) 3.11, 95% CI 1.59-6.08], whereas weight gain (OR 0.30, 95% CI 0.10-0.84) and male sex (OR 0.32, 95% CI 0.14-0.75) decreased the odds of fibrosis regression. On multivariable Cox regression analysis, predictors of fibrosis progression were weight gain [adjusted hazard ratio (aHR) 3.12, 95% CI 1.41-6.90] and MASLD (aHR 2.72, 95% CI 1.05-7.02). CONCLUSION: Fibrosis transitions are driven by metabolic health variables in PWH, independently of viral hepatitis coinfection and antiretroviral class therapy.
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Progressão da Doença , Fígado Gorduroso , Infecções por HIV , Cirrose Hepática , Aumento de Peso , Humanos , Masculino , Infecções por HIV/complicações , Feminino , Pessoa de Meia-Idade , Adulto , Fígado Gorduroso/patologia , Estudos de CoortesRESUMO
Artificial synapses based on resistive switching have emerged as a promising avenue for brain-inspired computing. Hybrid metal halide perovskites have provided the opportunity to simplify resistive switching device architectures due to their mixed electronic-ionic conduction, yet the instabilities under operating conditions compromise their reliability. We demonstrate reliable resistive switching and synaptic behaviour in layered benzylammonium (BzA) based halide perovskites of (BzA)2PbX4 composition (X = Br, I), showing a transformation of the resistive switching from digital to analog with the change of the halide anion. While (BzA)2PbI4 devices demonstrate gradual set and reset processes with reduced power consumption, the (BzA)2PbBr4 system features a more abrupt switching behaviour. Moreover, the iodide-based system displays excellent retention and endurance, whereas bromide-based devices achieve a superior on/off ratio. The underlying mechanism is attributed to the migration of halide ions and the formation of halide vacancy conductive filaments. As a result, the corresponding devices emulate synaptic characteristics, demonstrating the potential for neuromorphic computing. Such resistive switching and synaptic behaviour highlight (BzA)2PbX4 perovskites as promising candidates for non-volatile memory and neuromorphic computing.
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Altered metabolic function has many detrimental effects on the body that can manifest as cardiovascular and liver diseases. Traditional approaches to understanding and treating metabolic dysfunction-associated disorders have been organ-centered, leading to silo-type disease care. However, given the broad impact that systemic metabolic dysfunction has on the human body, approaches that simultaneously involve multiple medical specialists need to be developed and encouraged to optimize patient outcomes. In this review, we highlight how several of the treatments developed for cardiac care may have a beneficial effect on the liver and vice versa, suggesting that there is a need to target the disease process, rather than specifically target the cardiovascular or liver specific sequelae of metabolic dysfunction.
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Cardiologia , Gastroenterologia , Humanos , Cardiologia/métodos , Gastroenterologia/métodos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/terapia , Fígado/metabolismo , Fígado/patologia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/terapiaRESUMO
OBJECTIVE: The objectives of this study were to describe the trajectories of bone mineral density (BMD) and trabecular bone score (TBS) changes throughout pre-menopause (reproductive phase and menopausal transition) and post-menopause (early and late menopause) in women with HIV (WWH) undergoing different antiretroviral therapies (ARTs) and explore the risk factors associated with those changes. METHODS: This was an observational longitudinal retrospective study in WWH with a minimum of two DEXA evaluations comprising BMD and TBS measurements, both in the pre-menopausal and post-menopausal periods. Menopause was determined according to the STRAW+10 criteria, comprising four periods: the reproductive period, menopausal transition, and early- and late-menopausal periods. Mixed-effects models were fitted to estimate the trajectories of the two outcomes (BMD and TBS) over time. Annualized lumbar BMD and TBS absolute and percentage changes were calculated in each STRAW+10 time window. A backward elimination procedure was applied to obtain the final model, including the predictors that affected the trajectories of BMD or TBS over time. RESULTS: A total of 202 WWH, all Caucasian, were included. In detail, 1954 BMD and 195 TBS data were analyzed. The median number of DEXA evaluations per woman was 10 (IQR: 7, 12). The median observation periods per patient were 12.0 years (IQR = 8.9-14.4) for BMD and 6.0 years (IQR: 4.3, 7.9) for TBS. The prevalence of osteopenia (63% vs. 76%; p < 0.001) and osteoporosis (16% vs. 36%; p < 0.001) increased significantly between the pre-menopausal and post-menopausal periods. Both BMD (1.03 (±0.14) vs. 0.92 (±0.12) g/cm2; p < 0.001) and TBS (1.41 (IQR: 1.35, 1.45) vs. 1.32 (IQR: 1.28, 1.39); p < 0.001) decreased significantly between the two periods. The trend in BMD decreased across the four STRAW+10 periods, with a slight attenuation only in the late-menopausal period when compared with the other intervals. The TBS slope did not significantly change throughout menopause. The delta mean values of TBS in WWH were lower between the menopausal transition and reproductive period compared with the difference between menopause and menopausal transition. CONCLUSIONS: Both BMD and TBS significantly decreased over time. The slope of the change in BMD and TBS significantly decreased in the menopausal transition, suggesting that this period should be considered by clinicians as a key time during which to assess bone health and modifiable risk factors in WWH.