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1.
Chemistry ; 30(23): e202304130, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38350013

RESUMO

Magnesium-based catalysts are becoming popular for hydroelementation reactions specially using p-block reagents. Based on the seminal report from Schäfer's group (ChemCatChem 2022, 14, e202201007), our study demonstrates that the reaction mechanisms exhibit a far greater degree of complexity than originally presumed. Magnesium has a variety of coordination modes (and access to different hybridizations) which allows this electron-deficient centre to modulate its catalytic power depending on the σ-donor properties of the reagent. DFT calculations demonstrate several reaction channels closely operating in these versatile catalysts. In addition, variations in limiting energy barriers resulting from catalyst modifications were examined as a function of the Hammett constant, thereby predicting enhanced efficiency in reaction conversions.

2.
J Phys Chem A ; 128(17): 3339-3350, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38651289

RESUMO

Recently, pyrrole cages have been synthesized that encapsulate ion pairs and silver(I) clusters to form intricate supramolecular capsules. We report here a computational analysis of these structures using density functional theory combined with a semiempirical tight-binding approach. We find that for neutral pyrrole cages, the Gibbs free energies of formation provide reliable predictions for the ratio of bound ions. For charged pyrrole cages, we find strong argentophilic interactions between Ag ions on the basis of the calculated bond indices and molecular orbitals. For the cage with the Ag4 cluster, we find two minimum-geometry conformations that differ by only 6.5 kcal/mol, with an energy barrier <1 kcal/mol, suggesting a very flexible structure as indicated by molecular dynamics. The predicted energies of formation of [Agn⊂1]n-3+ (n = 1-5) cryptands provide low energy barriers of formation of 5-20 kcal/mol for all cases, which is consistent with the experimental data. Furthermore, we also examined the structural variability of mixed-valence silver clusters to test whether additional geometrical conformations inside the organic cage are thermodynamically accessible. In this context, we show that the time-dependent density functional theory UV-vis spectra may potentially serve as a diagnostic probe to characterize mixed-valence and geometrical configurations of silver clusters encapsulated into cryptands.

3.
J Allergy Clin Immunol ; 152(6): 1493-1519, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37678572

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects. OBJECTIVE: We sought to systematically synthesize the benefits and harms of AD prescription topical treatments. METHODS: For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT databases to September 5, 2022, for randomized trials addressing AD topical treatments. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. We classified topical corticosteroids (TCS) using 7 groups-group 1 being most potent. This review is registered in the Open Science Framework (https://osf.io/q5m6s). RESULTS: The 219 included trials (43,123 patients) evaluated 68 interventions. With high-certainty evidence, pimecrolimus improved 6 of 7 outcomes-among the best for 2; high-dose tacrolimus (0.1%) improved 5-among the best for 2; low-dose tacrolimus (0.03%) improved 5-among the best for 1. With moderate- to high-certainty evidence, group 5 TCS improved 6-among the best for 3; group 4 TCS and delgocitinib improved 4-among the best for 2; ruxolitinib improved 4-among the best for 1; group 1 TCS improved 3-among the best for 2. These interventions did not increase harm. Crisaborole and difamilast were intermediately effective, but with uncertain harm. Topical antibiotics alone or in combination may be among the least effective. To maintain AD control, group 5 TCS were among the most effective, followed by tacrolimus and pimecrolimus. CONCLUSIONS: For individuals with AD, pimecrolimus, tacrolimus, and moderate-potency TCS are among the most effective in improving and maintaining multiple AD outcomes. Topical antibiotics may be among the least effective.


Assuntos
Asma , Dermatite Atópica , Fármacos Dermatológicos , Eczema , Humanos , Dermatite Atópica/tratamento farmacológico , Tacrolimo/uso terapêutico , Metanálise em Rede , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fármacos Dermatológicos/uso terapêutico , Asma/tratamento farmacológico , Antibacterianos/uso terapêutico
4.
J Allergy Clin Immunol ; 152(6): 1470-1492, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37678577

RESUMO

BACKGROUND: Atopic dermatitis (AD) is an inflammatory skin condition with multiple systemic treatments and uncertainty regarding their comparative impact on AD outcomes. OBJECTIVE: We sought to systematically synthesize the benefits and harms of AD systemic treatments. METHODS: For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, Web of Science, and GREAT databases from inception to November 29, 2022, for randomized trials addressing systemic treatments and phototherapy for AD. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. This review is registered in the Open Science Framework (https://osf.io/e5sna). RESULTS: The 149 included trials (28,686 patients with moderate-to-severe AD) evaluated 75 interventions. With high-certainty evidence, high-dose upadacitinib was among the most effective for 5 of 6 patient-important outcomes; high-dose abrocitinib and low-dose upadacitinib were among the most effective for 2 outcomes. These Janus kinase inhibitors were among the most harmful in increasing adverse events. With high-certainty evidence, dupilumab, lebrikizumab, and tralokinumab were of intermediate effectiveness and among the safest, modestly increasing conjunctivitis. Low-dose baricitinib was among the least effective. Efficacy and safety of azathioprine, oral corticosteroids, cyclosporine, methotrexate, mycophenolate, phototherapy, and many novel agents are less certain. CONCLUSIONS: Among individuals with moderate-to-severe AD, high-certainty evidence demonstrates that high-dose upadacitinib is among the most effective in addressing multiple patient-important outcomes, but also is among the most harmful. High-dose abrocitinib and low-dose upadacitinib are effective, but also among the most harmful. Dupilumab, lebrikizumab, and tralokinumab are of intermediate effectiveness and have favorable safety.


Assuntos
Asma , Dermatite Atópica , Eczema , Humanos , Dermatite Atópica/tratamento farmacológico , Metanálise em Rede , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
5.
Angew Chem Int Ed Engl ; 63(4): e202316489, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38032333

RESUMO

The use of 2,5-diformylpyrrole in self-assembly reactions with diamines and Zn(II)/Cd(II) salts allowed the preparation of [2]catenane, trefoil knot, and Borromean rings. The intrinsically dynamic nature of the diiminopyrrole motif rendered all of the formed assemblies intramolecularly flexible. The presence of diiminopyrrole revealed new coordination motifs and influenced the host-guest chemistry of the systems, as illustrated by hexafluorophosphate encapsulation by Borromean rings.

6.
J Am Chem Soc ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37916946

RESUMO

Ruthenium-based Hoveyda-type olefin metathesis catalysts bearing novel rigid spirocyclic alkyl amino carbenes (CAACs) have been developed. They are characterized by exceptional stability toward decomposition through ß-elimination and bimolecular pathways, thus enabling unprecedented efficiency in the cross-metathesis of seed oil-derived fatty acid esters with ethylene (ethenolysis). Catalyst loading as low as 100 ppb was applied to the ethenolysis of the model substrate methyl oleate, leading to a remarkable turnover number (TON) of 2.6 million, significantly higher than previously reported (TON 340 000 at 1 ppm and 744 000 at 0.5 ppm catalyst loading). Ethenolysis of methyl esters derived from high oleic sunflower oil and rapeseed oil, readily available on an industrial scale, inexpensive, and renewable feedstocks, was for the first time effectively carried out with 0.5 ppm catalyst loading with TON as high as 964 000.

7.
Am J Epidemiol ; 192(10): 1678-1687, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37254775

RESUMO

We aimed to assess the impact of allocation concealment and blinding on the results of coronavirus disease 2019 (COVID-19) trials, using the World Health Organization COVID-19 database (to February 2022). We identified 488 randomized trials comparing drug therapeutics with placebo or standard care in patients with COVID-19. We performed random-effects meta-regressions comparing the results of trials with and without allocation concealment and blinding of health-care providers and patients. We found that, compared with trials with allocation concealment, trials without allocation concealment may estimate treatments to be more beneficial for mortality, mechanical ventilation, hospital admission, duration of hospitalization, and duration of mechanical ventilation, but results were imprecise. We did not find compelling evidence that, compared with trials with blinding, trials without blinding produce consistently different results for mortality, mechanical ventilation, and duration of hospitalization. We found that trials without blinding may estimate treatments to be more beneficial for hospitalizations and duration of mechanical ventilation. We did not find compelling evidence that COVID-19 trials in which health-care providers and patients are blinded produce different results from trials without blinding, but trials without allocation concealment estimate treatments to be more beneficial compared with trials with allocation concealment. Our study suggests that lack of blinding may not always bias results but that evidence users should remain skeptical of trials without allocation concealment.


Assuntos
COVID-19 , Humanos , Viés , Hospitalização
8.
Rheumatology (Oxford) ; 62(5): 1860-1869, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36135792

RESUMO

OBJECTIVES: Cognitive dysfunction (CD) is a common manifestation of SLE that can have detrimental consequences for those affected. To date, no treatments have been approved for SLE-CD. This study aims to assess the association of azathioprine (AZA) and mycophenolate (MMF) use with SLE-CD, given that these medications have demonstrated neuroprotective qualities in prior studies. METHODS: Consecutive adult SLE patients presenting to a single healthcare center were considered for participation. The ACR neuropsychological battery for SLE was administered to consenting patients at 0, 6 and 12 months. Scores were compared with age- and sex-matched controls. Primary outcome was CD, defined as a z-score ≤-1.5 in two or more cognitive domains. Mixed-effects logistic regression models were constructed to estimate the odds of CD with respect to AZA and MMF use. RESULTS: A total of 300 participants representing 676 patient visits completed the study; 114 (38%) met criteria for CD at baseline. The cumulative AZA dose (g/kg) was associated with reduced odds of CD [odds ratio (OR) 0.76 (95% CI 0.58, 0.98), P = 0.04]. Years of AZA treatment was also associated with reduced odds of CD [OR 0.72 (95% CI 0.54, 0.97), P = 0.03]. MMF use was not associated with CD. CONCLUSION: AZA use was associated with significantly lower odds of SLE-CD, while MMF use was not. Additional studies are warranted to further investigate the relationship of AZA and SLE-CD.


Assuntos
Azatioprina , Lúpus Eritematoso Sistêmico , Adulto , Humanos , Azatioprina/uso terapêutico , Ácido Micofenólico/uso terapêutico , Imunossupressores/uso terapêutico , Inibidores Enzimáticos , Cognição , Lúpus Eritematoso Sistêmico/tratamento farmacológico
9.
Rheumatology (Oxford) ; 62(11): 3610-3618, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36394258

RESUMO

OBJECTIVE: To phenotype SLE based on symptom burden (disease damage, system involvement and patient reported outcomes), with a specific focus on objective and subjective cognitive function. METHODS: SLE patients ages 18-65 years underwent objective cognitive assessment using the ACR Neuropsychological Battery (ACR-NB) and data were collected on demographic and clinical variables, disease burden/activity, health-related quality of life (HRQoL), depression, anxiety, fatigue and perceived cognitive deficits. Similarity network fusion (SNF) was used to identify patient subtypes. Differences between the subtypes were evaluated using Kruskal-Wallis and χ2 tests. RESULTS: Of the 238 patients, 90% were female, with a mean age of 41 years (s.d. 12) and a disease duration of 14 years (s.d. 10) at the study visit. The SNF analysis defined two subtypes (A and B) with distinct patterns in objective and subjective cognitive function, disease burden/damage, HRQoL, anxiety and depression. Subtype A performed worst on all significantly different tests of objective cognitive function (P < 0.03) compared with subtype B. Subtype A also had greater levels of subjective cognitive function (P < 0.001), disease burden/damage (P < 0.04), HRQoL (P < 0.001) and psychiatric measures (P < 0.001) compared with subtype B. CONCLUSION: This study demonstrates the complexity of cognitive impairment (CI) in SLE and that individual, multifactorial phenotypes exist. Those with greater disease burden, from SLE-specific factors or other factors associated with chronic conditions, report poorer cognitive functioning and perform worse on objective cognitive measures. By exploring different ways of phenotyping SLE we may better define CI in SLE. Ultimately this will aid our understanding of personalized CI trajectories and identification of appropriate treatments.


Assuntos
Disfunção Cognitiva , Lúpus Eritematoso Sistêmico , Humanos , Feminino , Adulto , Masculino , Qualidade de Vida/psicologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Ansiedade , Aprendizado de Máquina
10.
J Exp Bot ; 74(9): 2891-2911, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36723875

RESUMO

Climate change has intensified the infection of tomato plants by pathogens such as Pseudomonas syringae pv. tomato (Pst). Rootstocks may increase plant tolerance to leaf phytopathogens. The aim of this study was to evaluate the effects of the tolerant Poncho Negro (R) tomato rootstock on physiological defence and the role of hydrogen sulfide (H2S) in susceptible Limachino (L) tomato plant responses to Pst attack. Ungrafted (L), self-grafted (L/L), and grafted (L/R) plants were infected with Pst. Rootstock increased the concentration of antioxidant compounds including ascorbate in the scion. Tolerant rootstock induced an increase of H2S in the scion, which correlated with enhanced expression of the SlAPX2 gene. A high accumulation of salicylic acid was observed in Pst-inoculated grafted L/L and L/R plants, but this was higher in L/R plants. The increase of H2S during Pst infection was associated with a reduction of ethylene in L/R plants. Our study indicates that the Poncho Negro rootstock reduced the symptoms of bacterial speck disease in the Limachino tomato plants, conferring tolerance to Pst infection. This study provides new knowledge about the impact of rootstock in the defence of tomato plants against leaf pathogens that could be used in sustainable management of tomato cultivation.


Assuntos
Pseudomonas syringae , Solanum lycopersicum , Solanum lycopersicum/genética , Plantas , Folhas de Planta/fisiologia , Doenças das Plantas/microbiologia
11.
Chemistry ; 29(62): e202302494, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37584302

RESUMO

While R2 C=N-R double bonds in organic imines are well established, the related iminoboranes R-B=N-R are either prone to oligomerization or can only be stabilized at sufficient steric congestion. In particular, the examples of unsubstituted parent B=N-H entity are rare. We demonstrate that the amino imidazoline-2-imine ligand system (HAmIm) not only gives rise to the isolation of a parent (AmIm)B=N-H iminoborane, but also to species of type (AmIm)B=N-SiMe3 with concomitant stabilization by lithium bromide. The double bond character in these systems is unambiguously corroborated by DFT calculations. The steric accessibility of the (AmIm)B=NH unit allows facile reactivity including metathesis reactions with C=O and C=S bonds, nucleophilic addition toward organic and organometallic carbonyl compounds, but also oxidative N-N coupling within a dimeric unit. Thus, the chemical behavior of the (AmIm)B=N-H and (AmIm)B=N-SiMe3 is distinctly different from that of organic imines.

12.
J Phys Chem A ; 127(45): 9465-9472, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37916964

RESUMO

Stereoselective control of the cross metathesis of olefins is a crucial aspect of synthetic procedures. In this study, we utilized density functional theory methods to calculate thermodynamic and kinetic descriptors to explore the stereoselectivity of cross metathesis between allylbenzene and 2-butene-1,4-diyl diacetate. A ruthenium-based complex, characterized primarily by an anthracene-9-thiolate ligand, was designed in silico to completely restrict the E conformation of olefins through a bottom-bound mechanism. Our investigation of the kinetics of all feasible propagation routes demonstrated that Z-stereoisomers of metathesis products can be synthesized with an energy cost of only 13 kcal/mol. As a result, we encourage further research into the synthetic strategies outlined in this work.

13.
Phytother Res ; 37(3): 1092-1114, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36480428

RESUMO

The SARS-CoV-2 outbreak has been one of the largest public health crises globally, while thrombotic complications have emerged as an important factor contributing to mortality. Therefore, compounds that regulate the processes involved in thrombosis could represent a dietary strategy to prevent thrombotic complications involved in COVID-19. In August 2022, various databases were consulted using the keywords "flavonoids", "antiplatelet", "anticoagulant", "fibrinolytic", and "nitric oxide". Studies conducted between 2019 and 2022 were chosen. Flavonoids, at concentrations mainly between 2 and 300 µM, are capable of regulating platelet aggregation, blood coagulation, fibrinolysis, and nitric oxide production due to their action on multiple receptors and enzymes. Most of the studies have been carried out through in vitro and in silico models, and limited studies have reported the in vivo and clinical effect of flavonoids. Currently, quercetin has been the only flavonoid evaluated clinically in patients with COVID-19 for its effect on D-dimer levels. Therefore, clinical studies in COVID-19 patients analyzing the effect on platelet, coagulant, fibrinolytic, and nitric oxide parameters are required. In addition, further high-quality studies that consider cytotoxic safety and bioavailability are required to firmly propose flavonoids as a treatment for the thrombotic complications implicated in COVID-19.


Assuntos
COVID-19 , Trombose , Humanos , COVID-19/complicações , Flavonoides , SARS-CoV-2 , Trombose/etiologia , Trombose/prevenção & controle , Óxido Nítrico
14.
Chemistry ; 28(12): e202103997, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35023235

RESUMO

The stabilization of elusive monomeric species containing multiple boron-chalcogen bonds has motivated the investigation of sophisticated ligand systems in the past few years. Recently, a series of neutral, Lewis acid-free chalcogenboranes were prepared by incorporation of an amido imidazoline-2-imine as the supporting ligand (Frank et al., Angew. Chem. Int. Ed. 2021, 60, 4633), resulting in well-defined molecular entities with pronounced multiple bond character, B=X (X=O, S, Se, Te). In view of the potential use of N-heterocyclic boranes (NHB=X) as ligands in catalysis and fine chemistry, we evaluated in this work the bonding properties of the new B=X compounds based on a π-backdonation model. The electronic properties of systems in question were modulated via systematic modifications of the NHB ring with respect to ligand variation, saturation, size, and heteroatom substitutions. Investigations into the B=X bond length and order, calculated by means of density functional theory methods, reveal enhanced B=X bonding properties for NHB rings with high electron delocalization in the NHB ring and bearing electron-withdrawing substituents; a fact that was also confirmed by computational assessment of electron interactions of the B=X species with a dicarbonyl manganese complex. We expect that the analysis will contribute to the rational optimization of existing ligands as well as the development of new moieties, which would further allow for exploration of new boron chemistry.

15.
Chemphyschem ; 23(23): e202200580, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36062870

RESUMO

The dissociative mechanism of initiation for a series of Hoveyda-Grubbs type metathesis catalysts modified at the para and meta positions in the isopropoxybenzylidene ligand is investigated by means of DFT calculations. The electron donating/withdrawing capacity of the ligand was screened through the incorporation of various substituents such as halogens, nitro, alkoxides, ketones, esters, amines, and amides. Variations in structural parameters, energy barriers for the Ru-O bond dissociation, and Ru-O bond strength were examined as a function of the Hammett constant. It was found that electronic properties of the catalysts such as chemical potential, hardness, and electrophilicity correlate linearly with the dissociative energy barriers. These findings enable a systematic rationalization and prediction of rate of precatalyst initiation through the calculation of only the HOMO-LUMO gap of catalysts, as the faster the initiation, the more electrophilic the catalyst.


Assuntos
Alcenos , Rutênio , Alcenos/química , Rutênio/química , Ligantes , Catálise , Ésteres
16.
Lupus ; 31(1): 45-54, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34957878

RESUMO

OBJECTIVE: We previously demonstrated the utility of the Automated Neuropsychological Assessment Metrics (ANAM) for screening cognitive impairment (CI) in patients with systemic lupus erythematosus (SLE) and developed composite indices for interpreting ANAM results. Our objectives here were to provide further support for the ANAM's concurrent criterion validity against the American College of Rheumatology neuropsychological battery (ACR-NB), identify the most discriminatory subtests and scores of the ANAM for predicting CI, and provide a new approach to interpret ANAM results using Classification and Regression Tree (CART) analysis. METHODS: 300 adult SLE patients completed an adapted ACR-NB and ANAM on the same day. As per objectives, six models were built using combinations of ANAM subtests and scores and submitted to CART analysis. Area under the curve (AUC) was calculated to evaluate the ANAM's criterion validity compared to the adapted ACR-NB; the most discriminatory ANAM subtests and scores in each model were selected, and performance of models with the highest AUCs were compared to our previous composite indices; decision trees were generated for models with the highest AUCs. RESULTS: Two models had excellent AUCs of 86 and 89%. Eight most discriminatory ANAM subtests and scores were identified. Both models demonstrated higher AUCs against our previous composite indices. An adapted decision tree was created to simplify the interpretation of ANAM results. CONCLUSION: We provide further validity evidence for the ANAM as a valid CI screening tool in SLE. The decision tree improves interpretation of ANAM results, enhancing clinical utility.


Assuntos
Disfunção Cognitiva , Lúpus Eritematoso Sistêmico , Reumatologia , Adulto , Benchmarking , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Testes Neuropsicológicos
17.
Europace ; 24(2): 313-330, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34878119

RESUMO

We aim to provide a critical appraisal of basic concepts underlying signal recording and processing technologies applied for (i) atrial fibrillation (AF) mapping to unravel AF mechanisms and/or identifying target sites for AF therapy and (ii) AF detection, to optimize usage of technologies, stimulate research aimed at closing knowledge gaps, and developing ideal AF recording and processing technologies. Recording and processing techniques for assessment of electrical activity during AF essential for diagnosis and guiding ablative therapy including body surface electrocardiograms (ECG) and endo- or epicardial electrograms (EGM) are evaluated. Discussion of (i) differences in uni-, bi-, and multi-polar (omnipolar/Laplacian) recording modes, (ii) impact of recording technologies on EGM morphology, (iii) global or local mapping using various types of EGM involving signal processing techniques including isochronal-, voltage- fractionation-, dipole density-, and rotor mapping, enabling derivation of parameters like atrial rate, entropy, conduction velocity/direction, (iv) value of epicardial and optical mapping, (v) AF detection by cardiac implantable electronic devices containing various detection algorithms applicable to stored EGMs, (vi) contribution of machine learning (ML) to further improvement of signals processing technologies. Recording and processing of EGM (or ECG) are the cornerstones of (body surface) mapping of AF. Currently available AF recording and processing technologies are mainly restricted to specific applications or have technological limitations. Improvements in AF mapping by obtaining highest fidelity source signals (e.g. catheter-electrode combinations) for signal processing (e.g. filtering, digitization, and noise elimination) is of utmost importance. Novel acquisition instruments (multi-polar catheters combined with improved physical modelling and ML techniques) will enable enhanced and automated interpretation of EGM recordings in the near future.


Assuntos
Fibrilação Atrial , Cardiologia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/terapia , Mapeamento Potencial de Superfície Corporal , Átrios do Coração , Humanos , América Latina
18.
BMC Health Serv Res ; 21(1): 179, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632200

RESUMO

BACKGROUND: Patient engagement (PE) in planning or improving hospital facilities or services is one approach for improving healthcare delivery and outcomes. To provide evidence on hospital capacity needed to support PE, we described the attributes of hospital PE capacity associated with clinical quality measures. METHODS: We conducted a cross-sectional survey of general and specialty hospitals based on the Measuring Organizational Readiness for Patient Engagement framework. We derived a PE capacity index measure, and with Multiple Correspondence Analysis, assessed the association of PE capacity with hospital type, and rates of hand-washing, C. difficile infection rates and 30-day readmission. RESULTS: Respondents (91, 66.4%) included general: < 100 beds (48.4%), 100+ beds (27.5%), teaching hospitals (11.0%) and specialty (13.2%) hospitals. Most featured PE in multiple clinical and corporate departments. Most employed PE in a range of Planning (design/improve facilities 94.5%, develop strategic plans 87.9%), Evaluation/Quality Improvement (accreditation 91.2%, develop QI plans 90.1%) and Service Delivery activities (develop information/communication aids 92.3%). Hospitals enabled PE with multiple supports (median 12, range 0 to 25), most often: 76.9% strategic plan recognizes PE, 74.7% patient/family advisory council, and 69.2% pool of patient volunteers; and least often: 30.0% PE staff, 26.4% PE funding and 16.5% patient reimbursement or 3.3% compensation. Hospitals employed a range of less (inform, consult) and more (involve, partner) active modes of engagement. Two variables accounted for 29.6% of variance in hospital PE capacity index measure data: number of departments featuring PE and greater use of active engagement modes. PE capacity was not associated with general hospital type or clinical quality measures. CONCLUSIONS: Hospitals with fewer resources can establish favourable PE conditions by deploying PE widely and actively engaging patients. Healthcare policy-makers, hospital executives and PE managers can use these findings to allocate PE resources. Future research should explore how PE modes and methods impact clinical outcomes.


Assuntos
Clostridioides difficile , Participação do Paciente , Estudos Transversais , Serviços de Saúde , Hospitais , Humanos
19.
Sensors (Basel) ; 21(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921468

RESUMO

BACKGROUND: End-stage renal disease patients undergoing hemodialysis (ESRD-HD) therapy are highly susceptible to malignant ventricular arrhythmias caused by undetected potassium concentration ([K+]) variations (Δ[K+]) out of normal ranges. Therefore, a reliable method for continuous, noninvasive monitoring of [K+] is crucial. The morphology of the T-wave in the electrocardiogram (ECG) reflects Δ[K+] and two time-warping-based T-wave morphological parameters, dw and its heart-rate corrected version dw,c, have been shown to reliably track Δ[K+] from the ECG. The aim of this study is to derive polynomial models relating dw and dw,c with Δ[K+], and to test their ability to reliably sense and quantify Δ[K+] values. METHODS: 48-hour Holter ECGs and [K+] values from six blood samples were collected from 29 ESRD-HD patients. For every patient, dw and dw,c were computed, and linear, quadratic, and cubic fitting models were derived from them. Then, Spearman's (ρ) and Pearson's (r) correlation coefficients, and the estimation error (ed) between Δ[K+] and the corresponding model-estimated values (Δ^[K+]) were calculated. RESULTS AND DISCUSSIONS: Nonlinear models were the most suitable for Δ[K+] estimation, rendering higher Pearson's correlation (median 0.77 ≤r≤ 0.92) and smaller estimation error (median 0.20 ≤ed≤ 0.43) than the linear model (median 0.76 ≤r≤ 0.86 and 0.30 ≤ed≤ 0.40), even if similar Spearman's ρ were found across models (median 0.77 ≤ρ≤ 0.83). CONCLUSION: Results support the use of nonlinear T-wave-based models as Δ[K+] sensors in ESRD-HD patients.


Assuntos
Dinâmica não Linear , Diálise Renal , Arritmias Cardíacas , Eletrocardiografia , Humanos , Projetos Piloto , Potássio
20.
Rheumatology (Oxford) ; 59(10): 3032-3041, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32191334

RESUMO

OBJECTIVES: To examine for latent patterns of SLE disease activity trajectories that associate with specific latent patterns of health-related quality of life (HRQoL; Medical Outcomes Study Short Form-36), and to determine baseline predictors of class membership. METHODS: In this retrospective longitudinal inception cohort of 222 SLE adults over 10 years, trajectories of three outcomes were studied jointly: Short Form-36 physical (PCS) and mental (MCS) component summaries and adjusted mean SLEDAI-2000 (AMS). Group-based joint trajectory modelling was used to model latent classes; univariable and multivariable analyses were used to identify predictors of class membership. RESULTS: Four latent classes were identified: Class 1 (C1) (24%) had moderate AMS, and persistently low PCS and MCS; C2 (26%) had low AMS, moderate PCS and improved then worsened MCS; C3 (38%) had moderate AMS, and persistently high PCS and MCS; and C4 (11%) had high AMS, moderate-low PCS and improving MCS. Baseline older age was associated with lower HRQoL trajectories. Higher AMS trajectories did not associate with a particular pattern of HRQoL trajectory. A higher prevalence of fibromyalgia (44% in C1) was associated with worse HRQoL trajectories. Disease manifestations, organ damage and cumulative glucocorticoid were not differentially distributed across the latent classes. CONCLUSION: High disease activity did not necessarily associate with low HRQoL. More patients with worse HRQoL trajectories had fibromyalgia. Older age at diagnosis increased the probability of belonging to a class with low HRQoL trajectories. The care of SLE patients may be improved through addressing fibromyalgia in addition to disease activity.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Saúde Mental , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Adulto , Fatores Etários , Análise de Variância , Feminino , Fibromialgia/complicações , Fibromialgia/psicologia , Nível de Saúde , Humanos , Estudos Longitudinais , Lúpus Eritematoso Sistêmico/psicologia , Masculino , Estudos Retrospectivos , Reumatologia/normas , Sociedades Médicas/normas , Fatores de Tempo
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