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1.
Nature ; 572(7770): 511-515, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31435056

RESUMO

Lithium metal anodes offer high theoretical capacities (3,860 milliampere-hours per gram)1, but rechargeable batteries built with such anodes suffer from dendrite growth and low Coulombic efficiency (the ratio of charge output to charge input), preventing their commercial adoption2,3. The formation of inactive ('dead') lithium- which consists of both (electro)chemically formed Li+ compounds in the solid electrolyte interphase and electrically isolated unreacted metallic Li0 (refs 4,5)-causes capacity loss and safety hazards. Quantitatively distinguishing between Li+ in components of the solid electrolyte interphase and unreacted metallic Li0 has not been possible, owing to the lack of effective diagnostic tools. Optical microscopy6, in situ environmental transmission electron microscopy7,8, X-ray microtomography9 and magnetic resonance imaging10 provide a morphological perspective with little chemical information. Nuclear magnetic resonance11, X-ray photoelectron spectroscopy12 and cryogenic transmission electron microscopy13,14 can distinguish between Li+ in the solid electrolyte interphase and metallic Li0, but their detection ranges are limited to surfaces or local regions. Here we establish the analytical method of titration gas chromatography to quantify the contribution of unreacted metallic Li0 to the total amount of inactive lithium. We identify the unreacted metallic Li0, not the (electro)chemically formed Li+ in the solid electrolyte interphase, as the dominant source of inactive lithium and capacity loss. By coupling the unreacted metallic Li0 content to observations of its local microstructure and nanostructure by cryogenic electron microscopy (both scanning and transmission), we also establish the formation mechanism of inactive lithium in different types of electrolytes and determine the underlying cause of low Coulombic efficiency in plating and stripping (the charge and discharge processes, respectively, in a full cell) of lithium metal anodes. We propose strategies for making lithium plating and stripping more efficient so that lithium metal anodes can be used for next-generation high-energy batteries.

2.
Nano Lett ; 24(25): 7557-7563, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38758657

RESUMO

Ultrathin topological insulator membranes are building blocks of exotic quantum matter. However, traditional epitaxy of these materials does not facilitate stacking in arbitrary orders, while mechanical exfoliation from bulk crystals is also challenging due to the non-negligible interlayer coupling therein. Here we liberate millimeter-scale films of the topological insulator Bi2Se3, grown by molecular beam epitaxy, down to 3 quintuple layers. We characterize the preservation of the topological surface states and quantum well states in transferred Bi2Se3 films using angle-resolved photoemission spectroscopy. Leveraging the photon-energy-dependent surface sensitivity, the photoemission spectra taken with 6 and 21.2 eV photons reveal a transfer-induced migration of the topological surface states from the top to the inner layers. By establishing clear electronic structures of the transferred films and unveiling the wave function relocation of the topological surface states, our work lays the physics foundation crucial for the future fabrication of artificially stacked topological materials with single-layer precision.

3.
Rheumatology (Oxford) ; 63(2): 358-365, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37129549

RESUMO

OBJECTIVES: To compare the incidence of major adverse cardiovascular events (MACEs), cancer and infective complications in RA patients using Janus kinase (JAKis) and TNF (TNFis) inhibitors. METHOD: A retrospective analysis of data from the Hong Kong Biologics Registry 2008-2021 was performed. RA patients who had ever used JAKis or TNFis were included. The incidence of MACEs, cancer and infections were compared between the two groups, with adjustment for confounding factors. RESULTS: A total of 2471 courses of JAKis (n = 551) and TNFis (n = 1920) were used in 1732 RA patients (83.7% women, age 53.8 [12.5] years; follow-up 6431 patient-years). JAKi users had significantly older age, more atherosclerotic risk factors and higher frequency of past malignancies. A total of 15 and 40 MACEs developed in the JAKi and TNFi users, respectively (incidence 1.34 vs 0.75 per 100 patient-years; P = 0.22). There was no significant difference in the incidence of cancers between the two groups (0.81 [JAKi] vs 0.85 [TNFi] per 100 patient-years; P = 0.25). The adjusted hazard ratios of MACE and cancer in the JAKi users were 1.36 (95% CI: 0.62, 2.96) (P = 0.44) and 0.87 (95% CI: 0.39, 1.95) (P = 0.74), respectively. Rates of infections were significantly higher in the JAKi than TNFi users (16.3 vs 9.9 per 100 patient-years; P = 0.02), particularly herpes zoster (3.49 vs 0.94 per 100 patient-years; P < 0.001). CONCLUSIONS: In a real-life setting, there is no increase in MACEs or cancers in users of JAKis compared with TNFis. However, the incidence of non-serious infections, including herpes zoster, was increased in users of JAKis.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Herpes Zoster , Neoplasias , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Produtos Biológicos/efeitos adversos , Estudos Retrospectivos , Hong Kong/epidemiologia , Antirreumáticos/efeitos adversos , Fator de Necrose Tumoral alfa , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/complicações , Herpes Zoster/induzido quimicamente , Herpes Zoster/epidemiologia , Janus Quinases , Sistema de Registros , Neoplasias/induzido quimicamente
4.
Nano Lett ; 23(15): 7062-7069, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37522917

RESUMO

Nonaqueous fluidic transport and ion solvation properties under nanoscale confinement are poorly understood, especially in ion conduction for energy storage and conversion systems. Herein, metal-organic frameworks (MOFs) and aprotic electrolytes are studied as a robust platform for molecular-level insights into electrolyte behaviors in confined spaces. By employing computer simulations, along with spectroscopic and electrochemical measurements, we demonstrate several phenomena that deviate from the bulk, including modulated solvent molecular configurations, aggregated solvation structures, and tunable transport mechanisms from quasi-solid to quasi-liquid in functionalized MOFs. Technologically, taking advantage of confinement effects may prove useful for addressing stability concerns associated with volatile organic electrolytes while simultaneously endowing ultrafast transport of solvates, resulting in improved battery performance, even at extreme temperatures. The molecular-level insights presented here further our understanding of structure-property relationships of complex fluids at the nanoscale, information that can be exploited for the predictive design of more efficient electrochemical systems.

5.
J Am Chem Soc ; 145(17): 9624-9633, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37071778

RESUMO

Sulfurized polyacrylonitrile (SPAN) represents a class of sulfur-bonded polymers, which have shown thousands of stable cycles as a cathode in lithium-sulfur batteries. However, the exact molecular structure and its electrochemical reaction mechanism remain unclear. Most significantly, SPAN shows an over 25% 1st cycle irreversible capacity loss before exhibiting perfect reversibility for subsequent cycles. Here, with a SPAN thin-film platform and an array of analytical tools, we show that the SPAN capacity loss is associated with intramolecular dehydrogenation along with the loss of sulfur. This results in an increase in the aromaticity of the structure, which is corroborated by a >100× increase in electronic conductivity. We also discovered that the conductive carbon additive in the cathode is instrumental in driving the reaction to completion. Based on the proposed mechanism, we have developed a synthesis procedure to eliminate more than 50% of the irreversible capacity loss. Our insights into the reaction mechanism provide a blueprint for the design of high-performance sulfurized polymer cathode materials.

6.
Rheumatology (Oxford) ; 62(9): 2998-3005, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36707997

RESUMO

OBJECTIVES: This study explored whether the excess cardiovascular (CV) disease (CVD) risk in RA could be ameliorated by suppression of inflammation using a treat-to-target (T2T) approach. We compared the CV event (CVE) incidence among ERA patients managed by a T2T strategy with a CV risk factor-matched non-RA population and a historical RA cohort (HRA). METHODS: This was an observational study using the city-wide hospital data and the ERA registry. ERA patients received T2T management while HRA patients received routine care. Each ERA/HRA patient was matched to three non-RA controls according to age, gender and CV risk factors. Patients on antiplatelet/anticoagulant agents, with pre-existing CVD, chronic kidney disease or other autoimmune diseases were excluded. All subjects were followed for up to 5 years. The primary end point was the first occurrence of a CVE. RESULTS: The incidence of CVE in the ERA cohort (n = 261) and ERA controls were similar with a hazard ratio of 0.53 (95% CI 0.15, 1.79). In contrast, the incidence of CVE in the HRA cohort (n = 268) was significantly higher than that of the HRA controls with a hazard ratio of 1.9 (95% CI 1.16, 3.13). The incidence of CVE in the ERA cohort was significantly lower than that of the HRA cohort and the difference became insignificant after adjusting for inflammation, the use of methotrexate and traditional CV risk factors. CONCLUSION: ERA patients managed by a T2T strategy did not develop excess CVE compared with CV risk factor-matched controls over 5 years.


Assuntos
Artrite Reumatoide , Doenças Cardiovasculares , Humanos , Estudos de Casos e Controles , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Metotrexato/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Inflamação/complicações , Fatores de Risco
7.
Chem Rev ; 120(14): 6878-6933, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32603100

RESUMO

All-solid-state batteries (ASSBs) have attracted enormous attention as one of the critical future technologies for safe and high energy batteries. With the emergence of several highly conductive solid electrolytes in recent years, the bottleneck is no longer Li-ion diffusion within the electrolyte. Instead, many ASSBs are limited by their low Coulombic efficiency, poor power performance, and short cycling life due to the high resistance at the interfaces within ASSBs. Because of the diverse chemical/physical/mechanical properties of various solid components in ASSBs as well as the nature of solid-solid contact, many types of interfaces are present in ASSBs. These include loose physical contact, grain boundaries, and chemical and electrochemical reactions to name a few. All of these contribute to increasing resistance at the interface. Here, we present the distinctive features of the typical interfaces and interphases in ASSBs and summarize the recent work on identifying, probing, understanding, and engineering them. We highlight the complicated, but important, characteristics of interphases, namely the composition, distribution, and electronic and ionic properties of the cathode-electrolyte and electrolyte-anode interfaces; understanding these properties is the key to designing a stable interface. In addition, conformal coatings to prevent side reactions and their selection criteria are reviewed. We emphasize the significant role of the mechanical behavior of the interfaces as well as the mechanical properties of all ASSB components, especially when the soft Li metal anode is used under constant stack pressure. Finally, we provide full-scale (energy, spatial, and temporal) characterization methods to explore, diagnose, and understand the dynamic and buried interfaces and interphases. Thorough and in-depth understanding on the complex interfaces and interphases is essential to make a practical high-energy ASSB.

8.
J Am Chem Soc ; 143(15): 5763-5770, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33825477

RESUMO

Lithium-rich nickel manganese cobalt oxide (LRNMC) is being explored as an alternative to stoichiometric nickel manganese cobalt oxide (NMC) cathode materials due to its higher, initially accessible, energy-storage capacity. This higher capacity has been associated with reversible O oxidation; however, the mechanism through which the change in O chemistry is accommodated by the surrounding cathode structure remains incomplete, making it challenging to design strategies to mitigate poor electrode performance resulting from extended cycling. Focusing on LRNMC cathodes, we identify nanoscale domains of lower electron density within the cathode as a structural consequence of O oxidation using small-angle X-ray scattering (SAXS) and operando X-ray diffraction (XRD). A feature observed in the small angle scattering region suggests the formation of nanopores, which first appears during O oxidation, and is partially reversible. This feature is not present in traditional cathode materials, including stoichiometric NMC and lithium nickel cobalt aluminum oxide (NCA) but appears to be common to other Li-rich systems tested here, Li2RuO3 and Li1.3Nb0.3Mn0.4O2.

9.
J Am Chem Soc ; 143(41): 17079-17089, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34610744

RESUMO

In parallel with advances in the synthesis of solid-state ionic conductors, there is a need to understand the underlying mechanisms behind their improved ionic conductivities. This can be achieved by obtaining an atomic level picture of the interplay between the structure of materials and the resultant ionic diffusion processes. To this end, the structure and dynamics of Mg2+-stabilized rotor phase material γ-Na3PO4, characterized by neutron scattering, are detailed in this work. The Mg2+-stabilized rotor phase is found to be thermally stable from 4 to 650 K. However, signatures of orientational disorder of the phosphate anions are also evident in the average structure. Long-range Na+ self-diffusion was probed by quasi-elastic neutron scattering and subsequently modeled via a jump diffusion matrix with consideration of the phosphate anion rotations. The resultant diffusion model points directly to coupled anion-cation dynamics. Our approach highlights the importance of considering the whole system when developing an atomic level picture of structure and dynamics, which is critical in the rational design and optimization of energy materials.

10.
Nat Mater ; 19(12): 1339-1345, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32719511

RESUMO

Lithium metal has been considered an ideal anode for high-energy rechargeable Li batteries, although its nucleation and growth process remains mysterious, especially at the nanoscale. Here, cryogenic transmission electron microscopy was used to reveal the evolving nanostructure of Li metal deposits at various transient states in the nucleation and growth process, in which a disorder-order phase transition was observed as a function of current density and deposition time. The atomic interaction over wide spatial and temporal scales was depicted by reactive molecular dynamics simulations to assist in understanding the kinetics. Compared to crystalline Li, glassy Li outperforms in electrochemical reversibility, and it has a desired structure for high-energy rechargeable Li batteries. Our findings correlate the crystallinity of the nuclei with the subsequent growth of the nanostructure and morphology, and provide strategies to control and shape the mesostructure of Li metal to achieve high performance in rechargeable Li batteries.

11.
Rheumatology (Oxford) ; 60(2): 737-750, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32793966

RESUMO

OBJECTIVES: We investigated circulating syndecan-1, HA and thrombomodulin levels in patients with biopsy-proven Class III/IV ± V LN and their clinico-pathological associations. Patients with non-renal SLE or non-lupus chronic kidney disease, and healthy subjects served as controls. METHODS: Serum syndecan-1, HA and thrombomodulin levels were determined by ELISAs. RESULTS: Syndecan-1, HA and thrombomodulin levels were significantly higher during active LN compared with remission (P < 0.01, for all), and correlated with the level of proteinuria, estimated glomerular filtration rate, anti-dsDNA antibodies, complement 3 and serum creatinine. Longitudinal studies showed that syndecan-1 and thrombomodulin levels increased prior to clinical renal flare by 3.6 months, while HA level increased at the time of nephritic flare, and the levels decreased in parallel with treatment response. Receiver operating characteristic curve analysis showed that syndecan-1 and thrombomodulin levels distinguished patients with active LN from healthy subjects, LN patients in remission, patients with active non-renal lupus and patients with non-lupus chronic kidney disease (receiver operating characteristic area under curve of 0.98, 0.91, 0.82 and 0.95, respectively, for syndecan-1; and area under curve of 1.00, 0.84, 0.97 and 0.79, respectively, for thrombomodulin). HA level distinguished active LN from healthy subjects, LN patients in remission and non-lupus chronic kidney disease (receiver operating characteristic area under curve of 0.82, 0.71 and 0.90, respectively) but did not distinguish between renal vs non-renal lupus. Syndecan-1 and thrombomodulin levels correlated with the severity of interstitial inflammation, while HA level correlated with chronicity grading in kidney biopsies of active LN. CONCLUSION: Our findings suggest potential utility of serum syndecan-1, thrombomodulin and HA levels in clinical management, and their potential contribution to LN pathogenesis.


Assuntos
Ácido Hialurônico/sangue , Nefrite Lúpica/sangue , Sindecana-1/sangue , Trombomodulina/sangue , Adulto , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Nefrite Lúpica/diagnóstico , Masculino , Curva ROC , Estudos Retrospectivos
12.
Lupus ; 30(7): 1039-1050, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33765901

RESUMO

OBJECTIVE: We investigated the clinico-pathological associations of serum VCAM-1 and ICAM-1 levels in patients with biopsy-proven Class III/IV±V lupus nephritis (LN). METHODS: Serum VCAM-1 and ICAM-1 levels were determined by ELISAs. Sera from patients with non-renal SLE or non-lupus chronic kidney disease (CKD), and healthy subjects served as controls. RESULTS: Seropositivity rate for VCAM-1 and ICAM-1 was 93.10% and 37.93% respectively at the time of nephritic flare, and 44.83% and 13.79% respectively at remission, with both showing higher levels during flare (P < 0.05, for both). VCAM-1 level correlated with proteinuria, serum creatinine, and anti-dsDNA antibodies, and inversely correlated with C3. VCAM-1 level also correlated with leukocyte infiltration and fibrinoid necrosis/karyorrhexis scores in active LN kidney biopsies. ICAM-1 level correlated with proteinuria, but not anti-dsDNA or C3, nor histopathological features. VCAM-1 level increased 4.5 months before renal flare, while ICAM-1 increase coincided with flare, and both decreased after treatment. ROC analysis showed that VCAM-1 distinguished active LN from healthy subjects, LN in remission, active non-renal lupus, and CKD (ROC AUC of 0.98, 0.86, 0.93 and 0.90 respectively). VCAM-1 level in combination with either proteinuria or C3 was superior in distinguishing active LN from remission compared to the measurement of individual markers. Serum ICAM-1 level distinguished active LN from healthy subjects and LN patients in remission (ROC AUC of 0.75 and 0.66 respectively), but did not distinguish between renal versus non-renal lupus. ICAM-1 level in combination with markers of endothelial cell activation (syndecan-1, hyaluronan and thrombomodulin) was superior to proteinuria, anti-dsDNA, or C3 in distinguishing active LN from quiescent disease. CONCLUSION: Our findings suggest potential utility of serum VCAM-1 and ICAM-1 in clinical management. Monitoring VCAM-1 may facilitate early diagnosis of flare. Combining selected biomarkers may be advantageous in diagnosing active LN. VCAM-1 may have a pathogenic role in renal parenchymal inflammation in active LN.


Assuntos
Molécula 1 de Adesão Intercelular/sangue , Nefrite Lúpica/metabolismo , Nefrite Lúpica/patologia , Molécula 1 de Adesão de Célula Vascular/sangue , Adulto , Anticorpos Antinucleares/sangue , Biomarcadores/sangue , Biópsia , Estudos de Casos e Controles , Complemento C3/metabolismo , Creatinina/sangue , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Ácido Hialurônico/sangue , Rim/patologia , Nefrite Lúpica/classificação , Nefrite Lúpica/diagnóstico , Masculino , Pessoa de Meia-Idade , Proteinúria/complicações , Proteinúria/diagnóstico , Curva ROC , Sindecana-1/sangue , Trombomodulina/sangue
13.
Proc Natl Acad Sci U S A ; 115(34): 8558-8562, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30082391

RESUMO

We report anomalous physical properties of high-quality single-crystalline FeSi over a wide temperature range of 1.8-400 K. The electrical resistivity ρ(T) can be described by activated behavior with an energy gap Δ = 57 meV between 150 and 67 K, below which the estimated energy gap is significantly smaller. The magneto-resistivity and Hall coefficient change sign in the vicinity of 67 K, suggesting a change of dominant charge carriers. At ∼19 K, ρ(T) undergoes a cross-over from semiconducting to metallic behavior which is very robust against external magnetic fields. The low-temperature metallic conductivity depends strongly on the width/thickness of the sample. In addition, no indication of a bulk-phase transition or onset of magnetic order is found down to 2 K from specific heat and magnetic susceptibility measurements. The measurements are consistent with one another and point to complex electronic transport behavior that apparently involves a conducting surface state in FeSi at low temperatures, suggesting the possibility that FeSi is a 3D topological insulator.

14.
Nano Lett ; 20(5): 2943-2949, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32176514

RESUMO

Thin film solid oxide fuel cells (TF-SOFCs) are attracting attention due to their ability to operate at comparatively lower temperatures (400-650 °C) that are unattainable for conventional anode-supported SOFCs (650-800 °C). However, limited cathode performance and cell scalability remain persistent issues. Here, we report a new approach of fabricating yttria-stabilized zirconia (YSZ)-based TF-SOFCs via a scalable magnetron sputtering process. Notable is the development and deposition of a porous La0.6Sr0.4Co0.2Fe0.8O2.95(LSCF)-based cathode with a unique fibrous nanostructure. This all-sputtered cell shows an open-circuit voltage of ∼1.0 V and peak power densities of ∼1.7 and ∼2.5 W/cm2 at 600 and 650 °C, respectively, under hydrogen fuel and air along with showing stable performance in short-term testing. The power densities obtained in this work are the highest among YSZ-based SOFCs at these low temperatures, which demonstrate the feasibility of fabricating exceptionally high-performance TF-SOFC cells with distinctive dense or porous nanostructures for each layer, as desired, by a sputtering process. This work illustrates a new, potentially low-cost, and scalable platform for the fabrication of next-generation TF-SOFCs with excellent power output and stability.

15.
Angew Chem Int Ed Engl ; 60(20): 11359-11369, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33751750

RESUMO

Commercialization of the lithium-sulfur battery is hampered by bottlenecks like low sulfur loading, high cathode porosity, uncontrollable Li2 Sx deposition and sluggish kinetics of Li2 S activation. Herein, we developed a densely stacked redox-active hexaazatrinaphthylene (HATN) polymer with a surface area of 302 m2 g-1 and a very high bulk density of ca. 1.60 g cm-3 . Uniquely, HATN polymer has a similar redox potential window to S, which facilitates the binding of Li2 Sx and its transformation chemistry within the bulky polymer host, leading to fast Li2 S/S kinetics. The compact polymer/S electrode presents a high sulfur loading of ca. 15 mgs cm-2 (200-µm thickness) with a low cathode porosity of 41 %. It delivers a high areal capacity of ca. 14 mAh cm-2 and good cycling stability (200 cycles) at electrolyte-sulfur (E/S) ratio of 5 µL mgs -1 . The assembled pouch cell delivers a cell-level high energy density of 303 Wh kg-1 and 392 Wh L-1 .

16.
Ann Rheum Dis ; 79(8): 1070-1076, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32448782

RESUMO

OBJECTIVES: To report the 10-year outcome of lupus nephritis (LN) treated with mycophenolate mofetil (MMF) or tacrolimus (TAC) induction in a randomised controlled trial. METHODS: Patients with active LN were treated with MMF or TAC combined with high-dose prednisolone. Responders were switched to azathioprine (AZA) at month 6. Clinical outcomes at 10 years (renal flares, renal function decline and mortality) were assessed. Factors affecting prognosis were studied by Cox regression. Urine protein-to-creatinine ratio (uPCr) and estimated glomerular filtration rate (eGFR) at different time points were evaluated for their prediction of a poor prognosis by receiver operating characteristic (ROC) analysis. RESULTS: 150 patients were studied (age 35.5±12.8 years). Complete renal response rate was similar between MMF (59%) and TAC-treated patients (62%; p=0.71). AZA maintenance was given to 79% patients. After 118.2±42 months, proteinuric and nephritic renal flares occurred in 34% and 37% of the MMF, and 53% and 30% of the TAC groups of patients, respectively (p=0.49). The cumulative incidence of a composite outcome of ↓eGFR ≥30%, chronic kidney disease stage 4/5 or death at 10 years was 33% in both groups (p=0.90). Factors independently associated with a poor renal prognosis were first-time LN (HR 0.12 (0.031 to 0.39); p=0.01), eGFR (HR 0.98 (0.96 to 0.99); p=0.008) and no response at month 6 (HR 5.18 (1.40 to 19.1); p=0.01). ROC analysis revealed an uPCr >0.75 and eGFR of <80 mL/min at month 18 best predicted a poor renal prognosis. CONCLUSIONS: Long-term data confirmed non-inferiority of TAC to MMF as induction therapy of LN. An uPCr≤0.75 and eGFR of ≥80 mL/min at month 18 best predicted a favourable 10-year outcome and may be suitable targets for induction/consolidation therapy. TRIAL REGISTRATION NUMBER: NCT00371319.


Assuntos
Imunossupressores/uso terapêutico , Quimioterapia de Indução/métodos , Nefrite Lúpica/tratamento farmacológico , Ácido Micofenólico/uso terapêutico , Tacrolimo/uso terapêutico , Adulto , Azatioprina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Quimioterapia de Manutenção/métodos , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Exacerbação dos Sintomas , Tempo , Resultado do Tratamento
17.
Ann Rheum Dis ; 79(10): 1320-1326, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32737113

RESUMO

OBJECTIVE: To examine whether Disease Activity in Psoriatic Arthritis (DAPSA) reflecting the inflammatory component of psoriatic arthritis (PsA) can predict cardiovascular (CV) events independent of traditional CV risk factors and subclinical carotid atherosclerosis. METHODS: A cohort analysis was performed in patients with PsA who had been followed since 2006. The outcome of interest was first CV event. Four different CV disease (CVD) risk scores and DAPSA were computed at baseline. The presence of carotid plaque (CP) and carotid intima-media thickness (CIMT) was also determined in a subgroup of patients using high-resolution ultrasound. The association between DAPSA, CVD risk scores, CP, CIMT and the occurrence of CV events was assessed using Cox proportional hazard models. RESULTS: 189 patients with PsA (mean age: 48.9 years; male: 104 (55.0%)) were recruited. After a median follow-up of 9.9 years, 27 (14.3%) patients developed a CV event. Higher DAPSA was significantly associated with an increased risk of developing CV events (HR: 1.04, 95% CI (1.01 to 1.08), p=0.009). The association remained significant after adjusting for all CV risk scores in the multivariable models. In the subgroup analysis, 154 patients underwent carotid ultrasound assessment and 23 (14.9%) of them experienced a CV event. CP was associated with increased risk of developing CV events after adjusting for three CV risk scores and DAPSA, with HR ranging from 2.35 to 3.42. CONCLUSION: Higher DAPSA and the presence of CP could independently predict CVD events in addition to traditional CV risk scores in patients with PsA.


Assuntos
Artrite Psoriásica/complicações , Doenças Cardiovasculares/epidemiologia , Estenose das Carótidas/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índice de Gravidade de Doença
18.
Rheumatology (Oxford) ; 59(10): 2881-2892, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087023

RESUMO

OBJECTIVE: PsA patients who achieved sustained minimal disease activity (sMDA) had less subclinical atherosclerosis progression. The vascular effects of achieving other potential treatment targets, including the PsA Disease Activity Score (PASDAS) and the Disease Activity in PsA (DAPSA) score, remained uncertain. This study aimed to compare the vascular effects of achieving different treatment targets in PsA patients. METHOD: This is a post hoc analysis of a 2 year treat-to-target study aimed at MDA. A total of 101 consecutive PsA patients without overt cardiovascular disease were recruited. High-resolution carotid ultrasound and arterial stiffness markers were assessed annually. Low disease activity (LDA) was defined as MDA, DAPSA ≤14 or PASDAS ≤3.2. Sustained disease control was defined as achieving these targets at each visit from month 12 until month 24. RESULTS: Ninety patients [52 male (57.8%), age 50 years (s.d. 11)] who completed 24 months of follow-up were included in this analysis. A total of 44%, 48% and 45% of patients achieved sustained DAPSA LDA (sDAPDA-LDA), sustained PASDAS LDA (sPASDAS-LDA) and sMDA, respectively. Patients who achieved sMDA had significantly less progression of carotid intima-media thickness than those who did not (P = 0.031). Using multivariate analysis, achieving sMDA and sPASDAS-LDA had a protective effect on plaque progression, less increase in total plaque area, reduced mean intima-media thickness and reduced augmentation index after adjusting for covariates. In contrast, no significant differences in the progression of vascular parameters were demonstrated between patients who did or did not achieve sDAPSA-LDA. CONCLUSION: Achieving sMDA/sDASPAS-LDA, but not sDAPSA-LDA, was associated with a protective effect in subclinical atherosclerosis and arterial stiffness progression. A multidimensional domain of disease control might be better in minimizing cardiovascular risk in PsA.


Assuntos
Artrite Psoriásica/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Espessura Intima-Media Carotídea , Rigidez Vascular , Aterosclerose/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Placa Aterosclerótica/diagnóstico por imagem , Indução de Remissão , Fatores de Tempo
19.
Angew Chem Int Ed Engl ; 59(11): 4572-4580, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-31914215

RESUMO

A gas-phase approach to form Zn coordination sites on metal-organic frameworks (MOFs) by vapor-phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution-phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO2 to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200-300 mV. Using element-specific X-ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square-pyramidal geometry with four Zn-N bonds in the equatorial plane and one Zn-OH2 bond in the axial plane. The fine-tuned internal strain was further supported by monitoring changes in XRD and UV/Visible absorption spectra across a range of infiltration cycles. The ability to use internal strain to increase catalytic activity of MOFs suggests that applying this strategy will enhance intrinsic catalytic capabilities of a variety of porous materials.

20.
Chem Rev ; 117(21): 13123-13186, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-28960962

RESUMO

Rechargeable battery technologies have ignited major breakthroughs in contemporary society, including but not limited to revolutions in transportation, electronics, and grid energy storage. The remarkable development of rechargeable batteries is largely attributed to in-depth efforts to improve battery electrode and electrolyte materials. There are, however, still intimidating challenges of lower cost, longer cycle and calendar life, higher energy density, and better safety for large scale energy storage and vehicular applications. Further progress with rechargeable batteries may require new chemistries (lithium ion batteries and beyond) and better understanding of materials electrochemistry in the various battery technologies. In the past decade, advancement of battery materials has been complemented by new analytical techniques that are capable of probing battery chemistries at various length and time scales. Synchrotron X-ray techniques stand out as one of the most effective methods that allow for nearly nondestructive probing of materials characteristics such as electronic and geometric structures with various depth sensitivities through spectroscopy, scattering, and imaging capabilities. This article begins with the discussion of various rechargeable batteries and associated important scientific questions in the field, followed by a review of synchrotron X-ray based analytical tools (scattering, spectroscopy, and imaging) and their successful applications (ex situ, in situ, and in operando) in gaining fundamental insights into these scientific questions. Furthermore, electron microscopy and spectroscopy complement the detection length scales of synchrotron X-ray tools and are also discussed toward the end. We highlight the importance of studying battery materials by combining analytical techniques with complementary length sensitivities, such as the combination of X-ray absorption spectroscopy and electron spectroscopy with spatial resolution, because a sole technique may lead to biased and inaccurate conclusions. We then discuss the current progress of experimental design for synchrotron experiments and methods to mitigate beam effects. Finally, a perspective is provided to elaborate how synchrotron techniques can impact the development of next-generation battery chemistries.

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