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1.
Hepatology ; 80(1): 152-162, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446707

RESUMO

BACKGROUND AND AIMS: High levels of serum matrix metalloproteinase-7 (MMP-7) have been linked to biliary atresia (BA), with wide variation in concentration cutoffs. We investigated the accuracy of serum MMP-7 as a diagnostic biomarker in a large North American cohort. APPROACH AND RESULTS: MMP-7 was measured in serum samples of 399 infants with cholestasis in the Prospective Database of Infants with Cholestasis study of the Childhood Liver Disease Research Network, 201 infants with BA and 198 with non-BA cholestasis (age median: 64 and 59 days, p = 0.94). MMP-7 was assayed on antibody-bead fluorescence (single-plex) and time resolved fluorescence energy transfer assays. The discriminative performance of MMP-7 was compared with other clinical markers. On the single-plex assay, MMP-7 generated an AUROC of 0.90 (CI: 0.87-0.94). At cutoff 52.8 ng/mL, it produced sensitivity = 94.03%, specificity = 77.78%, positive predictive value = 64.46%, and negative predictive value = 96.82% for BA. AUROC for gamma-glutamyl transferase = 0.81 (CI: 0.77-0.86), stool color = 0.68 (CI: 0.63-0.73), and pathology = 0.84 (CI: 0.76-0.91). Logistic regression models of MMP-7 with other clinical variables individually or combined showed an increase for MMP-7+gamma-glutamyl transferase AUROC to 0.91 (CI: 0.88-0.95). Serum concentrations produced by time resolved fluorescence energy transfer differed from single-plex, with an optimal cutoff of 18.2 ng/mL. Results were consistent within each assay technology and generated similar AUROCs. CONCLUSIONS: Serum MMP-7 has high discriminative properties to differentiate BA from other forms of neonatal cholestasis. MMP-7 cutoff values vary according to assay technology. Using MMP-7 in the evaluation of infants with cholestasis may simplify diagnostic algorithms and shorten the time to hepatoportoenterostomy.


Assuntos
Atresia Biliar , Biomarcadores , Metaloproteinase 7 da Matriz , Humanos , Metaloproteinase 7 da Matriz/sangue , Atresia Biliar/diagnóstico , Atresia Biliar/sangue , Biomarcadores/sangue , Lactente , Feminino , Masculino , Recém-Nascido , Estudos de Coortes , Colestase/diagnóstico , Colestase/sangue , Estudos Prospectivos
2.
J Am Chem Soc ; 146(32): 22570-22582, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39083620

RESUMO

Understanding the nature of metal-ligand bonding is a major challenge in actinide chemistry. We present a new experimental strategy for addressing this challenge using actinide 3d4f resonant inelastic X-ray scattering (RIXS). Through a systematic study of uranium(IV) halide complexes, [UX6]2-, where X = F, Cl, or Br, we identify RIXS spectral satellites with relative energies and intensities that relate to the extent of uranium-ligand bond covalency. By analyzing the spectra in combination with ligand field density functional theory we find that the sensitivity of the satellites to the nature of metal-ligand bonding is due to the reduction of 5f interelectron repulsion and 4f-5f spin-exchange, caused by metal-ligand orbital mixing and the degree of 5f radial expansion, known as central-field covalency. Thus, this study furthers electronic structure quantification that can be obtained from 3d4f RIXS, demonstrating it as a technique for estimating actinide-ligand covalency.

3.
J Am Chem Soc ; 146(20): 13962-13973, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38727611

RESUMO

Dimeric complexes composed of d8 square planar metal centers and rigid bridging ligands provide model systems to understand the interplay between attractive dispersion forces and steric strain in order to assist the development of reliable methods to model metal dimer complexes more broadly. [Ir2 (dimen)4]2+ (dimen = para-diisocyanomenthane) presents a unique case study for such phenomena, as distortions of the optimal structure of a ligand with limited conformational flexibility counteract the attractive dispersive forces from the metal and ligand to yield a complex with two ground state deformational isomers. Here, we use ultrafast X-ray solution scattering (XSS) and optical transient absorption spectroscopy (OTAS) to reveal the nature of the equilibrium distribution and the exchange rate between the deformational isomers. The two ground state isomers have spectrally distinct electronic excitations that enable the selective excitation of one isomer or the other using a femtosecond duration pulse of visible light. We then track the dynamics of the nonequilibrium depletion of the electronic ground state population─often termed the ground state hole─with ultrafast XSS and OTAS, revealing a restoration of the ground state equilibrium in 2.3 ps. This combined experimental and theoretical study provides a critical test of various density functional approximations in the description of bridged d8-d8 metal complexes. The results show that density functional theory calculations can reproduce the primary experimental observations if dispersion interactions are added, and a hybrid functional, which includes exact exchange, is used.

4.
Hepatology ; 77(5): 1639-1653, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626628

RESUMO

BACKGROUND AND AIMS: Biliary atresia (BA), a congenital cholestatic liver disease, commonly culminates in end-stage liver disease. We previously demonstrated in BA that Prominin-1 ( Prom1 )-expressing hepatic progenitor cells (HPCs) expand within regions of developing fibrosis, giving rise to cholangiocytes within biliary ductular reactions. Null mutation of Prom1 or ablation of cells expressing Prom1 significantly diminishes fibrogenesis. FN14, the receptor for TNF-like weak inducer of apoptosis (TWEAK), is expressed by HPCs. TWEAK/FN14 signaling promotes fibrosis in multiple organ systems. Therefore, we hypothesized that TWEAK/FN14 signaling mediates Prom1 -expressing HPC proliferation leading to profibrogenic ductular reactions in BA. APPROACH AND RESULTS: The experimental mouse model of BA mediated by perinatal rhesus rotavirus (RRV) infection resulted in increased co-expression of Fn14 in Prom1 -expressing HPCs within regions of ductular reactions. FN14 antagonist L524-0366 decreased ductular reactions, biliary fibrosis and periportal fibroblast activation in RRV injury. L524-0366 inhibition also demonstrated loss of downstream noncanonical NF-kB signaling expression in RRV injury. Murine HPC organoids demonstrated accelerated organoid growth and proliferation when treated with recombinant TWEAK. Increased organoid proliferation with recombinant TWEAK was lost when also treated with L524-0366. Analysis of a large publicly available RNA sequencing database of BA and normal control patients revealed significant increases in expression of PROM1 , FN14 , and genes downstream of TNF signaling and noncanonical NF-κB signaling pathways in BA infants. Infants who failed to achieve bile drainage after hepatoportoenterostomy had higher relative levels of FN14 expression. CONCLUSION: TWEAK/FN14 signaling activation in Prom1 -expressing HPCs contributes to proliferation of profibrogenic ductular reactions in BA.


Assuntos
Atresia Biliar , Infecções por Rotavirus , Rotavirus , Animais , Camundongos , Antígeno AC133/genética , Atresia Biliar/metabolismo , Fibrose , Rotavirus/metabolismo , Células-Tronco/metabolismo , Fatores de Transcrição , Fatores de Necrose Tumoral/metabolismo , Fatores de Necrose Tumoral/farmacologia
5.
Hepatology ; 77(3): 862-873, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36131538

RESUMO

BACKGROUND AND AIMS: In biliary atresia, serum bilirubin is commonly used to predict outcomes after Kasai portoenterostomy (KP). Infants with persistently high levels invariably need liver transplant, but those achieving normalized levels have a less certain disease course. We hypothesized that serum bile acid levels could help predict outcomes in the latter group. APPROACH AND RESULTS: Participants with biliary atresia from the Childhood Liver Disease Research Network were included if they had normalized bilirubin levels 6 months after KP and stored serum samples from the 6-month post-KP clinic visit ( n  = 137). Bile acids were measured from the stored serum samples and used to divide participants into ≤40 µmol/L ( n  = 43) or >40 µmol/L ( n  = 94) groups. At 2 years of age, the ≤40 µmol/L compared with >40 µmol/L group had significantly lower total bilirubin, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, bile acids, and spleen size, as well as significantly higher albumin and platelet counts. Furthermore, during 734 person-years of follow-up, those in the ≤40 µmol/L group were significantly less likely to develop splenomegaly, ascites, gastrointestinal bleeding, or clinically evident portal hypertension. The ≤40 µmol/L group had a 10-year cumulative incidence of liver transplant/death of 8.5% (95% CI: 1.1%-26.1%), compared with 42.9% (95% CI: 28.6%-56.4%) for the >40 µmol/L group ( p  = 0.001). CONCLUSIONS: Serum bile acid levels may be a useful prognostic biomarker for infants achieving normalized bilirubin levels after KP.


Assuntos
Atresia Biliar , Lactente , Humanos , Criança , Atresia Biliar/cirurgia , Portoenterostomia Hepática , Prognóstico , Bilirrubina , Ácidos e Sais Biliares , Biomarcadores , Resultado do Tratamento , Estudos Retrospectivos
6.
Hepatology ; 77(2): 530-545, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069569

RESUMO

BACKGROUND AND AIMS: Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis. APPROACH AND RESULTS: A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS. CONCLUSIONS: Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.


Assuntos
Síndrome de Alagille , Colestase , Técnicas de Imagem por Elasticidade , Hepatopatias , Humanos , Criança , Fígado/patologia , Metaloproteinase 7 da Matriz , Endoglina , Interleucina-8 , Colestase/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatopatias/patologia , Biomarcadores , Síndrome de Alagille/patologia
7.
Acta Anaesthesiol Scand ; 68(4): 546-555, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38267221

RESUMO

The DEXamethasone twice for pain treatment after Total Knee Arthroplasty (DEX-2-TKA) trial showed that adding one and two doses of 24 mg intravenous dexamethasone to paracetamol, ibuprofen and local infiltration analgesia, reduced morphine consumption (primary outcome) within 48 h after TKA. We aimed to explore the differences in the effect of dexamethasone on morphine consumption in different subgroups. Quantile regression adjusted for site was used to test for significant interaction between the predefined dichotomised subgroups and treatment group. The subgroups were defined based on baseline data: sex (male/female), age (≤65 years/>65 years), American Society of Anaesthesiologists (ASA)-score (ASA I + II/III), visual analogue score of preoperative pain at rest (≤30 mm/>30 mm), pain during mobilisation (≤30 mm/>30 mm), type of anaesthesia (spinal anaesthesia/general anaesthesia and spinal converted to general anaesthesia), and prior daily use of analgesics (either paracetamol and/or NSAID/neither). These analyses were supplemented with post hoc multivariate linear regression analyses. Test of interaction comparing sex in the pairwise comparison between DX2 (dexamethasone [24 mg] + dexamethasone [24 mg]) versus placebo (p = .02), showed a larger effect of dexamethasone on morphine consumption in male patients compared to females. Test of interaction comparing age in the pairwise comparison between DX1 (dexamethasone [24 mg] + placebo) versus placebo (p = .04), showed a larger effect of dexamethasone on morphine consumption in younger patients (≤65 years) compared to older. All remaining subgroup analyses showed no evidence of a difference. The supplemental multivariate analyses did not support any significant interaction for sex (p = .256) or age (p = .730) but supported a significant interaction with the type of anaesthesia (p < .001). Our results from the quantile regression analyses indicate that the male sex and younger age (≤65 years) may be associated with a larger analgesic effect of dexamethasone than the effects in other types of patients. However, this is not supported by post-hoc multivariate linear regression analyses. The two types of analyses both supported a possible interaction with the type of anaesthesia.


Assuntos
Artroplastia do Joelho , Morfina , Humanos , Masculino , Feminino , Idoso , Morfina/uso terapêutico , Acetaminofen/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dexametasona/uso terapêutico , Analgésicos Opioides/uso terapêutico , Método Duplo-Cego
8.
Pediatr Surg Int ; 40(1): 46, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294551

RESUMO

PURPOSE: Pilonidal disease (PD) is marked by chronic inflammation and frequent recurrence which can decrease quality of life. However, debate remains regarding the optimal treatment for PD in the pediatric population. This study compares two recommended treatment approaches-excision with off-midline flap reconstruction (OMF: Bascom cleft lift flap, modified Limberg flap) and minimally invasive endoscopic pilonidal sinus treatment (EPSiT). METHODS: Single-center retrospective evaluation of patients 1-21 years of age with PD who underwent either excision with OMF reconstruction or EPSiT between 10/1/2011 and 10/31/2021. Outcomes included were disease recurrence, reoperation, and wound complication rates. Comparisons were performed using Chi-square and Mann-Whitney U tests. RESULTS: 18 patients underwent excision/OMF reconstruction and 45 patients underwent EPSiT. The excision/OMF reconstruction cohort was predominantly male (44.4% vs 17.8% p = 0.028), with history of prior pilonidal infection (33.3% vs 6.7%; p = 0.006), and longer median operative time (60 min vs 17 min; p < 0.001). The excision/OMF reconstruction cohort had a higher rate of wound complications (22.2% vs 0%; p = 0.001), but lower rates of disease recurrence (5.6% vs 33.3%; p = 0.022) and reoperation (5.6% vs 31.1%; p = 0.031). CONCLUSION: In pediatric patients with PD, excision with OMF reconstruction may decrease recurrence and reoperation rates with increased operative times and wound complication rates, compared to EPSiT.


Assuntos
Seio Pilonidal , Dermatopatias , Humanos , Criança , Masculino , Feminino , Seio Pilonidal/cirurgia , Qualidade de Vida , Estudos Retrospectivos , Endoscopia , Reoperação
9.
Clin Infect Dis ; 76(3): e82-e89, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35938291

RESUMO

BACKGROUND: Many interventional in-patient coronavirus disease 2019 (COVID-19) trials assess primary outcomes through day 28 post-randomization. Since a proportion of patients experience protracted disease or relapse, such follow-up period may not fully capture the course of the disease, even when randomization occurs a few days after hospitalization. METHODS: Among adults hospitalized with COVID-19 in eastern Denmark from 18 March 2020-12 January 2021 we assessed all-cause mortality, recovery, and sustained recovery 90 days after admission, and readmission and all-cause mortality 90 days after discharge. Recovery was defined as hospital discharge and sustained recovery as recovery and alive without readmissions for 14 consecutive days. RESULTS: Among 3386 patients included in the study, 2796 (82.6%) reached recovery and 2600 (77.0%) achieved sustained recovery. Of those discharged from hospital, 556 (19.9%) were readmitted and 289 (10.3%) died. Overall, the median time to recovery was 6 days (interquartile range [IQR]: 3-10), and 19 days (IQR: 11-33) among patients in intensive care in the first 2 days of admission. CONCLUSIONS: Postdischarge readmission and mortality rates were substantial. Therefore, sustained recovery should be favored to recovery outcomes in clinical COVID-19 trials. A 28-day follow-up period may be too short for the critically ill.


Assuntos
COVID-19 , Adulto , Humanos , Readmissão do Paciente , Alta do Paciente , Assistência ao Convalescente , SARS-CoV-2 , Hospitalização , Hospitais , Mortalidade Hospitalar
10.
Ann Oncol ; 34(3): 262-274, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36535565

RESUMO

BACKGROUND: Patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) have a poor prognosis. The phase III KESTREL study evaluated the efficacy of durvalumab [programmed death-ligand 1 (PD-L1) antibody] with or without tremelimumab [cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody], versus the EXTREME regimen in patients with R/M HNSCC. PATIENTS AND METHODS: Patients with HNSCC who had not received prior systemic treatment for R/M disease were randomized (2 : 1 : 1) to receive durvalumab 1500 mg every 4 weeks (Q4W) plus tremelimumab 75 mg Q4W (up to four doses), durvalumab monotherapy 1500 mg Q4W, or the EXTREME regimen (platinum, 5-fluorouracil, and cetuximab) until disease progression. Durvalumab efficacy, with or without tremelimumab, versus the EXTREME regimen in patients with PD-L1-high tumors and in all randomized patients was assessed. Safety was also assessed. RESULTS: Durvalumab and durvalumab plus tremelimumab were not superior to EXTREME for overall survival (OS) in patients with PD-L1-high expression [median, 10.9 and 11.2 versus 10.9 months, respectively; hazard ratio (HR) = 0.96; 95% confidence interval (CI) 0.69-1.32; P = 0.787 and HR = 1.05; 95% CI 0.80-1.39, respectively]. Durvalumab and durvalumab plus tremelimumab prolonged duration of response versus EXTREME (49.3% and 48.1% versus 9.8% of patients remaining in response at 12 months), correlating with long-term OS for responding patients; however, median progression-free survival was longer with EXTREME (2.8 and 2.8 versus 5.4 months). Exploratory analyses suggested that subsequent immunotherapy use by 24.3% of patients in the EXTREME regimen arm contributed to the similar OS outcomes between arms. Grade 3/4 treatment-related adverse events (TRAEs) for durvalumab, durvalumab plus tremelimumab, and EXTREME were 8.9%, 19.1%, and 53.1%, respectively. CONCLUSIONS: In patients with PD-L1-high expression, OS was comparable between durvalumab and the EXTREME regimen. Durvalumab alone, and with tremelimumab, demonstrated durable responses and reduced TRAEs versus the EXTREME regimen in R/M HNSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Antígeno B7-H1 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia , Neoplasias de Cabeça e Pescoço/etiologia
11.
Hepatology ; 76(3): 712-726, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35271743

RESUMO

BACKGROUND AND AIMS: The natural history of gastroesophageal variceal hemorrhage (VH) in biliary atresia (BA) is not well characterized. We analyzed risk factors, incidence, and outcomes of VH in a longitudinal multicenter study. APPROACH AND RESULTS: Participants enrolled in either an incident (Prospective Database of Infants with Cholestasis [PROBE]) or prevalent (Biliary Atresia Study of Infants and Children [BASIC]) cohort of BA were included. Variceal hemorrhage (VH) was defined based on gastrointestinal bleeding in the presence of varices accompanied by endoscopic or nontransplant surgical intervention. Cumulative incidence of VH and transplant-free survival was compared based on features of portal hypertension (e.g., splenomegaly, thrombocytopenia) and clinical parameters at baseline in each cohort (PROBE: 1.5 to 4.5 months after hepatoportoenterostomy [HPE]; BASIC: at enrollment > 3 years of age). Analyses were conducted on 869 children with BA enrolled between June 2004 and December 2020 (521 in PROBE [262 (51%) with a functioning HPE] and 348 in BASIC). The overall incidence of first observed VH at 5 years was 9.4% (95% CI: 7.0-12.4) in PROBE and 8.0% (5.2-11.5) in BASIC. Features of portal hypertension, platelet count, total bilirubin, aspartate aminotransferase (AST), albumin, and AST-to-platelet ratio index at baseline were associated with an increased risk of subsequent VH in both cohorts. Transplant-free survival at 5 years was 45.1% (40.5-49.6) in PROBE and 79.2% (74.1-83.4) in BASIC. Two (2.5%) of 80 participants who had VH died, whereas 10 (12.5%) underwent transplant within 6 weeks of VH. CONCLUSIONS: The low risk of VH and associated mortality in children with BA needs to be considered in decisions related to screening for varices and primary prophylaxis of VH.


Assuntos
Atresia Biliar , Varizes Esofágicas e Gástricas , Hipertensão Portal , Varizes , Atresia Biliar/complicações , Atresia Biliar/cirurgia , Criança , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/prevenção & controle , Humanos , Hipertensão Portal/etiologia , Lactente , Varizes/complicações
12.
Phys Chem Chem Phys ; 25(35): 23417-23434, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37486006

RESUMO

We apply ultrashort X-ray laser pulses to track optically excited structural dynamics of [Ir2(dimen)4]2+ molecules in solution. In our exploratory study we determine angular correlations in the scattered X-rays, which comprise a complex fingerprint of the ultrafast dynamics. Model-assisted analysis of the experimental correlation data allows us to elucidate various aspects of the photoinduced changes in the excited molecular ensembles. We unambiguously identify that in our experiment the photoinduced transition dipole moments in [Ir2(dimen)4]2+ molecules are oriented perpendicular to the Ir-Ir bond. The analysis also shows that the ground state conformer of [Ir2(dimen)4]2+ with a larger Ir-Ir distance is mostly responsible for the formation of the excited state. We also reveal that the ensemble of solute molecules can be characterized with a substantial structural heterogeneity due to solvent influence. The proposed X-ray correlation approach offers an alternative path for studies of ultrafast structural dynamics of molecular ensembles in the liquid and gas phases.

13.
Phys Chem Chem Phys ; 25(4): 3309-3322, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36630169

RESUMO

The magnetic properties of the nickelalumite-type layered double hydroxides (LDH), MAl4(OH)12(SO4)·3H2O (MAl4-LDH) with M = Co2+ (S = 3/2), Ni2+ (S = 1), or Cu2+ (S = 1/2) were determined by a combined experimental and computational approach. They represent three new inorganic, low-dimensional magnetic systems with a defect-free, structurally ordered magnetic lattice. They exhibit no sign of magnetic ordering down to 2 K in contrast to conventional hydrotalcite LDH. Detailed insight into the complex interplay between the choice of magnetic ion (M2+) and magnetic properties was obtained by a combination of magnetic susceptibility, heat capacity, neutron scattering, solid-state NMR spectroscopy, and first-principles calculations. The NiAl4- and especially CoAl4-LDH have pronounced zero-field splitting (ZFS, easy-axis and easy-plane, respectively) and weak ferromagnetic nearest-neighbour interactions. Thus, they are rare examples of predominantly zero-dimensional spin systems in dense, inorganic matrices. In contrast, CuAl4-LDH (S = 1/2) consists of weakly ferromagnetic S = 1/2 spin chains. For all three MAl4-LDH, good agreement is found between the experimental magnetic parameters (J, D, g) and first-principles quantum chemical calculations, which also predict that the interchain couplings are extremely weak (< 0.1 cm-1). Thus, our approach will be valuable for evaluation and prediction of magnetic properties in other inorganic materials.

14.
Nature ; 543(7647): 695-699, 2017 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28358064

RESUMO

Transition-metal complexes are used as photosensitizers, in light-emitting diodes, for biosensing and in photocatalysis. A key feature in these applications is excitation from the ground state to a charge-transfer state; the long charge-transfer-state lifetimes typical for complexes of ruthenium and other precious metals are often essential to ensure high performance. There is much interest in replacing these scarce elements with Earth-abundant metals, with iron and copper being particularly attractive owing to their low cost and non-toxicity. But despite the exploration of innovative molecular designs, it remains a formidable scientific challenge to access Earth-abundant transition-metal complexes with long-lived charge-transfer excited states. No known iron complexes are considered photoluminescent at room temperature, and their rapid excited-state deactivation precludes their use as photosensitizers. Here we present the iron complex [Fe(btz)3]3+ (where btz is 3,3'-dimethyl-1,1'-bis(p-tolyl)-4,4'-bis(1,2,3-triazol-5-ylidene)), and show that the superior σ-donor and π-acceptor electron properties of the ligand stabilize the excited state sufficiently to realize a long charge-transfer lifetime of 100 picoseconds (ps) and room-temperature photoluminescence. This species is a low-spin Fe(iii) d5 complex, and emission occurs from a long-lived doublet ligand-to-metal charge-transfer (2LMCT) state that is rarely seen for transition-metal complexes. The absence of intersystem crossing, which often gives rise to large excited-state energy losses in transition-metal complexes, enables the observation of spin-allowed emission directly to the ground state and could be exploited as an increased driving force in photochemical reactions on surfaces. These findings suggest that appropriate design strategies can deliver new iron-based materials for use as light emitters and photosensitizers.

15.
Eur J Anaesthesiol ; 40(3): 155-170, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36325886

RESUMO

BACKGROUND: Postoperative analgesic effects of systemic glucocorticoids given as an adjunct to treatment are largely undetermined in alloplastic procedures. OBJECTIVES: To investigate the beneficial and harmful effects of peri-operative systemic glucocorticoid treatment for pain after total hip arthroplasty (THA) or total knee arthroplasty (TKA). DESIGN: A systematic review of randomised clinical trials (RCTs) with meta-analyses, trial sequential analyses and GRADE. Primary outcome was 24 h intravenous (i.v.) morphine (or equivalent) consumption with a predefined minimal important difference (MID) of 5 mg. Secondary outcomes included pain at rest and during mobilisation (MID, VAS 10 mm), adverse and serious adverse events (SAEs). DATA SOURCES: We searched EMBASE, Cochrane CENTRAL, PubMed and Google Scholar up to October 2021. ELIGIBILITY CRITERIA: RCTs investigating peri-operative systemic glucocorticoid versus placebo or no intervention, for analgesic pain management of patients at least 18 years undergoing planned THA or TKA, irrespective of publication date and language. RESULTS: We included 32 RCTs with 3521 patients. Nine trials were at a low risk of bias. Meta-analyses showed evidence of a reduction in 24 h cumulative morphine consumption with glucocorticoids by 5.0 mg (95% CI 2.2 to 7.7; P  = 0.0004). Pain at rest was reduced at 6 h by 7.8 mm (95% CI 5.5 to 10.2; P  < 0.00001), and at 24 h by 6.3 mm (95% CI 3.8 to 8.8; P  < 0.00001). Pain during mobilisation was reduced at 6 h by 9.8 mm (95% CI 6.9 to 12.8; P  < 0.00001), and at 24 h by 9.0 mm (95% CI 5.5 to 12.4, P  < 0.00001). Incidence of adverse events was generally lower in the glucocorticoid treatment group. SAEs were rarely reported. The GRADE rated quality of evidence was low to very low. CONCLUSION: Peri-operative systemic glucocorticoid treatment reduced postoperative morphine consumption to an individually relevant level following hip and knee arthroplasty. Pain levels were reduced but were below the predefined MID. The quality of evidence was generally low. REGISTRATION: PROSPERO ID: CRD42019135034.


Assuntos
Artroplastia do Joelho , Humanos , Artroplastia do Joelho/efeitos adversos , Glucocorticoides/efeitos adversos , Analgésicos , Morfina , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia
16.
J Acoust Soc Am ; 153(3): 1554, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37002091

RESUMO

We revisit the problem of constructing one-dimensional acoustic black holes. Instead of considering the Euler-Bernoulli beam theory, we use Timoshenko's approach, which is known to be more realistic at higher frequencies. Our goal is to minimize the reflection coefficient under a constraint imposed on the normalized wavenumber variation. We use the calculus of variations to derive the corresponding Euler-Lagrange equation analytically and then use numerical methods to solve this equation to find the "optimal" height profile for different frequencies. We then compare these profiles to the corresponding ones previously found using the Euler-Bernoulli beam theory and see that in the lower range of the dimensionless frequency Ω (defined using the largest height of the plate), the optimal profiles almost coincide, as expected.

17.
J Arthroplasty ; 38(12): 2592-2598.e2, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37286048

RESUMO

BACKGROUND: Perioperative dexamethasone as an adjunct to multimodal analgesia, has an opioid-sparing and pain alleviating effect after total knee arthroplasty (TKA), however, the 3-year effects are unknown. We aimed to investigate the 3-year effect of 1 (DX1) or 2 (DX2) intravenous doses of 24 mg dexamethasone or placebo on pain, physical function, and health-related quality of life after TKA. METHODS: Patients who participated in the Dexamethasone Twice for Pain Treatment after TKA (DEX-2-TKA) were invited to physical tests and questionnaires (self-reported characteristics, Oxford Knee Score, EuroQol-5Dimensions-5Levels (EQ5D5L), and PainDetect). The tests were 40-meter Fast Paced Walk (40FPW) test, Timed Up and Go (TUG), 30 Second Chair Stand test (30CST), Stair Climb Test (SCT), bilateral knee Range of Motion, and knee extension torque. For each test the peak pain intensity was registered on a 0 to 100 mm Visual Analogue Scale. Primary outcome was average peak pain intensity during the 40FPW, TUG, 30CST and SCT. Secondary outcomes were the tests and questionnaires. Out of 252 eligible patients, 133 (52.8%) underwent the tests and 160 (63.5%) answered the questionnaires. Mean follow-up time was 33 months (range, 23 to 40). RESULTS: Median (interquartile range) peak pain intensity was 0 (0 to 65) for the DX2 group, 0 (0 to 51) for DX1 group and 0 (0 to 70) for the placebo group (P = .72). No differences in secondary outcomes were identified. CONCLUSION: One or 2 intravenous doses of 24 mg dexamethasone did not impact chronic pain development or physical function 3 years after TKA.


Assuntos
Artroplastia do Joelho , Dor Crônica , Humanos , Artroplastia do Joelho/efeitos adversos , Seguimentos , Qualidade de Vida , Dexametasona/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle
18.
Int J Neuropsychopharmacol ; 25(7): 556-566, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35106566

RESUMO

OBJECTIVES: Successful treatment of delirium depends on the detection of the reversible contributors. Drugs with delirogenic properties are the most prevalent reversible cause of delirium. METHODS: This observational study is based on data from Arzneimittelsicherheit in der Psychiatrie, a multicenter drug surveillance program in German-speaking countries recording severe adverse drug reactions (ADRs) in psychiatric inpatients. The present study analyzes drug-induced delirium (DID) during treatment with antidepressants and antipsychotics. RESULTS: A total of 436 565 psychiatric inpatients were treated with antidepressants and/or antipsychotics during the observation period from 1993 to 2016 in the participating 110 hospitals. Overall, 254 cases (0.06% of all patients treated with antidepressants and/or antipsychotics) of DID were detected. Implicated either in combination or alone (multiple drugs were implicated in 70.1% of DID), clomipramine (0.24%), amitriptyline (0.21%), and clozapine (0.18%) showed the highest incidence rates of DID. When implicated alone (98 cases overall), clozapine (0.11%) followed by amitriptyline (0.05%) were most likely causally associated with the occurrence of DID. Drugs with strong antimuscarinic properties generally exhibited higher risk of DID. CONCLUSIONS: With an incidence rate of <0.1%, the use of antidepressants and antipsychotics was rarely associated with DID within the Arzneimittelsicherheit in der Psychiatrie program. Tricyclic antidepressants and clozapine were the most commonly implicated psychotropic drugs. These data support the specific role of antimuscarinic properties in DID.


Assuntos
Antipsicóticos , Clozapina , Delírio , Psicoses Induzidas por Substâncias , Sistemas de Notificação de Reações Adversas a Medicamentos , Amitriptilina , Antidepressivos/efeitos adversos , Antipsicóticos/efeitos adversos , Delírio/induzido quimicamente , Delírio/tratamento farmacológico , Delírio/epidemiologia , Humanos , Incidência , Antagonistas Muscarínicos
19.
Phys Rev Lett ; 129(5): 056001, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35960558

RESUMO

Time-resolved scattering experiments enable imaging of materials at the molecular scale with femtosecond time resolution. However, in disordered media they provide access to just one radial dimension thus limiting the study of orientational structure and dynamics. Here we introduce a rigorous and practical theoretical framework for predicting and interpreting experiments combining optically induced anisotropy and time-resolved scattering. Using impulsive nuclear Raman and ultrafast x-ray scattering experiments of chloroform and simulations, we demonstrate that this framework can accurately predict and elucidate both the spatial and temporal features of these experiments.

20.
Mol Psychiatry ; 26(3): 1009-1018, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31383926

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with a robust genetic influence. The norepinephrine transporter (NET) is of particular interest as it is one of the main targets in treatment of the disorder. As ADHD is a complex and polygenetic condition, the possible regulation by epigenetic processes has received increased attention. We sought to determine possible differences in NET promoter DNA methylation between patients with ADHD and healthy controls. DNA methylation levels in the promoter region of the NET were determined in 23 adult patients with ADHD and 23 healthy controls. A subgroup of 18 patients with ADHD and 18 healthy controls underwent positron emission tomography (PET) with the radioligand (S,S)-[18F]FMeNER-D2 to quantify the NET in several brain areas in vivo. Analyses revealed significant differences in NET methylation levels at several cytosine-phosphate-guanine (CpG) sites between groups. A defined segment of the NET promoter ("region 1") was hypermethylated in patients in comparison with controls. In ADHD patients, a negative correlation between methylation of a CpG site in this region and NET distribution in the thalamus, locus coeruleus, and the raphe nuclei was detected. Furthermore, methylation of several sites in region 1 was negatively associated with the severity of hyperactivity-impulsivity symptoms. Our results point to an epigenetic dysregulation in ADHD, possibly due to a compensatory mechanisms or additional factors involved in transcriptional processing.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Proteínas da Membrana Plasmática de Transporte de Norepinefrina , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Humanos , Comportamento Impulsivo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Tomografia por Emissão de Pósitrons
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