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1.
J Phys Chem A ; 2024 Apr 23.
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.

2.
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.

3.
J Biomol Struct Dyn ; 42(4): 1692-1710, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37232450

RESUMO

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Conventional antithrombotic therapy has reported hemorrhagic accidents. Ethnobotanical and scientific reports point to Cnidoscolus aconitifolius as an antithrombotic adjuvant. Previously, C. aconitifolius leaves ethanolic extract displayed antiplatelet, anticoagulant, and fibrinolytic activities. This work aimed to identify compounds from C. aconitifolius with in vitro antithrombotic activity through a bioassay-guided study. Antiplatelet, anticoagulant, and fibrinolytic tests guided the fractionation. Ethanolic extract was subjected to a liquid-liquid partitioning, followed by vacuum liquid, and size exclusion chromatography to obtain the bioactive JP10B fraction. The compounds were identified through UHPLC-QTOF-MS, and their molecular docking, bioavailability, and toxicological parameters were determined computationally. Kaempferol-3-O-glucorhamnoside and 15(S)-HPETE were identified; both showed affinity for antithrombotic targets, low absorption, and safety for human consumption. Further in vitro and in vivo evaluations will better understand their antithrombotic mechanism. This bioassay-guided fractionation demonstrated that C. aconitifolius ethanolic extract has antithrombotic compounds.Communicated by Ramaswamy H. Sarma.


Assuntos
Fibrinolíticos , Extratos Vegetais , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Simulação de Acoplamento Molecular , Fibrinolíticos/farmacologia , Disponibilidade Biológica , Etanol/química , Anticoagulantes/farmacologia
4.
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.

5.
J Thorac Cardiovasc Surg ; 167(3): 861-868, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37541572

RESUMO

OBJECTIVES: To determine the impact of older donor age (70+ years) on long-term survival and freedom from chronic lung allograft dysfunction in lung transplant (LTx) recipients. METHODS: A retrospective single-center study was performed on all LTx recipients from 2002 to 2017 and a modern subgroup from 2013 to 2017. Recipients were stratified into 4 groups based on donor lung age (<18, 18-55, 56-69, ≥70 years). Donor and recipient characteristics were compared using χ2 tests for differences in proportions and analysis of variance for differences in means. Univariable and multivariable Cox regression was used to describe differences in long-term survival and freedom from chronic lung allograft dysfunction. RESULTS: Between 2002 and 2017, 1600 LTx were performed, 98 of which were performed from donors aged 70 years or older. Recipients of 70+ years donor lungs were significantly older with a mean age of 55.5 ± 12.9 years old (P = .001) and had more Status 3 (urgent) recipients (37.4%, P = .002). After multivariable regression, there were no significant differences in survival or freedom from chronic lung allograft dysfunction between the 4 strata of recipients. CONCLUSIONS: Lung transplantation using donors 70 years old or older can be considered when all other parameters suggest excellent donor lung function without compromising short- or long-term outcomes.


Assuntos
Transplante de Pulmão , Doadores de Tecidos , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Fatores Etários , Transplante de Pulmão/efeitos adversos , Pulmão
6.
J Clin Epidemiol ; 166: 111238, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38081440

RESUMO

OBJECTIVES: Combining multivariate and network meta-analysis methods simultaneously in a multivariate network meta-analysis (MVNMA) provides the methodological framework to analyze the largest amount of evidence relevant to decision-makers (i.e., from indirect evidence and correlated outcomes). The objectives of this scoping review were to summarize the characteristics of MVNMAs published in the health sciences literature and map the methodological guidance available for MVNMA. STUDY DESIGN AND SETTING: We searched MEDLINE, Embase, and the Cumulative Index to Nursing and Allied Health Literature from inception to 28 August 2023, along with citations of included studies, for quantitative evidence syntheses that applied MVNMA and articles addressing MVNMA methods. Pairs of reviewers independently screened potentially eligible studies. Collected data included bibliographic, methodological, and analytical characteristics of included studies. We reported results as total numbers, frequencies, and percentages for categorical variables and medians and interquartile ranges for continuous variables that were not normally distributed. RESULTS: After screening 1,075 titles and abstracts, and 112 full texts, we included 38 unique studies, of which, 10 were quantitative evidence syntheses that applied MVNMA and 28 were articles addressing MVNMA methods. Among the 10 MVNMAs, the first was published in 2013, four used studies identified from already published systematic reviews, and eight addressed pharmacological interventions, which were the most common interventions. They evaluated interventions for metastatic melanoma, colorectal cancer, prostate cancer, oral hygiene, disruptive behavior disorders, rheumatoid arthritis, narcolepsy, type 2 diabetes, and overactive bladder syndrome. Five MVNMAs analyzed two outcomes simultaneously, and four MVNMAs analyzed three outcomes simultaneously. Among the articles addressing MVNMA methods, the first was published in 2007 and the majority provided methodological frameworks for conducting MVNMAs (26/28, 93%). One study proposed criteria to standardize reporting of MVNMAs and two proposed items relevant to the quality assessment of MVNMAs. Study authors used data from 18 different illnesses to provide illustrative examples within their methodological guidance. CONCLUSIONS: The application of MVNMA in the health sciences literature is uncommon. Many methodological frameworks are published; however, standardization and specific criteria to guide reporting and quality assessment are lacking. This overview of the current landscape may help inform future conduct of MVNMAs and research on MVNMA methods.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38083783

RESUMO

Sudden cardiac death is the leading cause of death among cardiovascular diseases. Markers for patient risk stratification focusing on QT-interval dynamics in response to heart-rate (HR) changes can be characterized in terms of parametric QT to RR dependence and QT/RR hysteresis. The QT/RR hysteresis can be quantified by the time delay the QT interval takes to accommodate for the HR changes. The exercise stress test has been proposed as a proper test, with large HR dynamics, to evaluate the QT/RR hysteresis. The present study aims at evaluating several time-delay estimators based on noise statistic (Gaussian or Laplacian) and HR changes profile at stress test (gradual transition change). The estimator's performance was assessed on a simulated QT transition contaminated by noise and in a clinical study including patients affected by coronary arteries disease (CAD). As expected, the Laplacian and Gaussian estimators yield the best results when noise follows the respective distribution. Further, the Laplacian estimator showed greater discriminative power in classifying different levels of cardiac risk in CAD patients, suggesting that real data fit better the Laplacian distribution than the Gaussian one. The Laplacian estimator appears to be the choice for time-delay estimation of QT/RR hysteresis lag in response to HR changes in stress test.Clinical Relevance-The proposed time-delay estimator of QT/RR hysteresis lag improves its significance as biomarkers for coronary artery diseases risk stratification.


Assuntos
Doença da Artéria Coronariana , Eletrocardiografia , Humanos , Eletrocardiografia/métodos , Teste de Esforço , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Frequência Cardíaca/fisiologia
8.
Front Plant Sci ; 14: 1326689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38143584

RESUMO

Tomato (Solanum lycopersicum L.) domestication and later introduction into Europe resulted in a genetic bottleneck that reduced genetic variation. Crosses with other wild tomato species from the Lycopersicon clade can be used to increase genetic diversity and improve important agronomic traits such as stress tolerance. However, many species in the Lycopersicon clade have intraspecific and interspecific incompatibility, such as gametophytic self-incompatibility and unilateral incompatibility. In this review, we provide an overview of the known incompatibility barriers in Lycopersicon. We begin by addressing the general mechanisms self-incompatibility, as well as more specific mechanisms in the Rosaceae, Papaveraceae, and Solanaceae. Incompatibility in the Lycopersicon clade is discussed, including loss of self-incompatibility, species exhibiting only self-incompatibility and species presenting both self-compatibility and self-incompatibility. We summarize unilateral incompatibility in general and specifically in Lycopersicon, with details on the 'self-compatible x self-incompatible' rule, implications of self-incompatibility in unilateral incompatibility and self-incompatibility-independent pathways of unilateral incompatibility. Finally, we discuss advances in the understanding of compatibility barriers and their implications for tomato breeding.

9.
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.

10.
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.

11.
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
12.
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
13.
Food Res Int ; 172: 113125, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689890

RESUMO

The use of carrier systems for the protection and delivery of bioactive compounds in the agri-food industry is an area of opportunity that requires the design of new systems and sources of materials for their structure. Chia seeds (Salvia hispanica L.) produce mucilage with functional qualities that allow their application in diverse areas of the food industry. These qualities have been used to form very stable carrier systems, such as capsules, emulsions, coatings, and films that can protect and prolong the functionalities of loaded compounds (e.g., antimicrobial and antioxidant capabilities). This paper presents a review of chia mucilage-based carrier systems and their applications in food products (micro-and nanoparticles, emulsions, coatings, and films for food packaging), as well as the current technological prospects of these systems. The use of chia mucilage in coatings and films shows a high potential for use in biodegradable, edible, and organic packaging. Although many studies have been conducted on chia mucilage encapsulation systems, there is still a gap in the application of capsules and particles in food.


Assuntos
Emulsões , Polissacarídeos , Cápsulas , Embalagem de Alimentos , Sementes
14.
IEEE J Biomed Health Inform ; 27(11): 5314-5325, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37651478

RESUMO

Variations in the dispersion of ventricular repolarization can be quantified by T-wave time-warping based index, dw. However, the early phase of the T-wave can be affected by ST-segment changes during ischemia. We hypothesized that restricting dw to the T-wave peak-to-end ( Tpe) would circumvent this limitation while still quantifying variations in repolarization dispersion. A total of 101 ECG recordings from patients undergoing coronary occlusion, together with their control recordings, were analyzed. A series of dw values was calculated by quantifying the Tpe morphological variations between the T-waves at different occlusion stages and a baseline T-wave. We introduced a normalized version of dw, Rd, reflecting variations of dw during occlusion relative to control recordings ( Rd = 1 corresponds to the same level of variation). The dw series followed a gradually increasing trend with occlusion time, reaching median [range] Rd values of 9.44 [1.01, 80.74] at the occlusion end. Rd at occlusion end was significantly higher than threshold values of 1, 2, 5, and 10 in 94.1%, 85.11%, 64.4% and 48.5% of patients, respectively. The spatial lead-wise analysis of dw showed distinct distributions depending on the occluded artery, suggesting a relation with the ischemia location. The relative variation R with ischemia of index dw (9.4) is greater than that of the T-wave amplitude (7.7), Tpe interval (2.7) and T-wave width (3.0). In conclusion, dw tracks ischemic-induced variations in repolarization dispersion in a more robust manner than classical indexes, avoiding the impact of ST segment elevation/depression or early T-wave distortions, thus warranting further clinical studies.


Assuntos
Arritmias Cardíacas , Eletrocardiografia , Humanos , Isquemia
15.
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.

16.
J Biomed Opt ; 28(7): 075004, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37484974

RESUMO

Significance: The number of injections administered has increased dramatically worldwide due to vaccination campaigns following the COVID-19 pandemic, creating a problem of disposing of syringes and needles. Accidental needle sticks occur among medical and cleaning staff, exposing them to highly contagious diseases, such as hepatitis and human immunodeficiency virus. In addition, needle phobia may prevent adequate treatment. To overcome these problems, we propose a needle-free injector based on thermocavitation. Aim: Experimentally study the dynamics of vapor bubbles produced by thermocavitation inside a fully buried 3D fused silica chamber and the resulting high-speed jets emerging through a small nozzle made at the top of it. The injected volume can range from ∼0.1 to 2 µL per shot. We also demonstrate that these jets have the ability to penetrate agar skin phantoms and ex-vivo porcine skin. Approach: Through the use of a high-speed camera, the dynamics of liquid jets ejected from a microfluidic device were studied. Thermocavitation bubbles are generated by a continuous wave laser (1064 nm). The 3D chamber was fabricated by ultra-short pulse laser-assisted chemical etching. Penetration tests are conducted using agar gels (1%, 1.25%, 1.5%, 1.75%, and 2% concentrations) and porcine tissue as a model for human skin. Result: High-speed camera video analysis showed that the average maximum bubble wall speed is about 10 to 25 m/s for almost any combination of pump laser parameters; however, a clever design of the chamber and nozzle enables one to obtain jets with an average speed of ∼70 m/s. The expelled volume per shot (0.1 to 2 µl) can be controlled by the pump laser intensity. Our injector can deliver up to 20 shots before chamber refill. Penetration of jets into agar of different concentrations and ex-vivo porcine skin is demonstrated. Conclusions: The needle-free injectors based on thermocavitation may hold promise for commercial development, due to their cost and compactness.


Assuntos
Hidrodinâmica , Injeções a Jato , Vacinação , Animais , Humanos , Ágar/química , Injeções a Jato/normas , Pele , Suínos , Vacinação/instrumentação , Modelos Anatômicos , Fotografação
17.
J Am Dent Assoc ; 154(8): 727-741.e10, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37500235

RESUMO

BACKGROUND: Corticosteroids are used to manage pain after surgical tooth extractions. The authors assessed the effect of corticosteroids on acute postoperative pain in patients undergoing surgical tooth extractions of mandibular third molars. TYPES OF STUDIES REVIEWED: The authors conducted a systematic review and meta-analysis. The authors searched the Epistemonikos database, including MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and the US clinical trials registry (ClinicalTrials.gov) from inception until April 2023. Pairs of reviewers independently screened titles and abstracts, then full texts of trials were identified as potentially eligible. After duplicate data abstraction, the authors conducted random-effects meta-analyses. Risk of bias was assessed using Version 2 of the Cochrane Risk of Bias tool and certainty of the evidence was determined using the Grading of Recommendations Assessment, Development and Evaluation approach. RESULTS: Forty randomized controlled trials proved eligible. The evidence suggested that corticosteroids compared with a placebo provided a trivial reduction in pain intensity measured 6 hours (mean difference, 8.79 points lower; 95% CI, 14.8 to 2.77 points lower; low certainty) and 24 hours after surgical tooth extraction (mean difference, 8.89 points lower; 95% CI, 10.71 to 7.06 points lower; very low certainty). The authors found no important difference between corticosteroids and a placebo with regard to incidence of postoperative infection (risk difference, 0%; 95% CI, -1% to 1%; low certainty) and alveolar osteitis (risk difference, 0%; 95% CI, -3% to 4%; very low certainty). PRACTICAL IMPLICATIONS: Low and very low certainty evidence suggests that there is a trivial difference regarding postoperative pain intensity and adverse effects of corticosteroids administered orally, submucosally, or intramuscularly compared with a placebo in patients undergoing third-molar extractions.


Assuntos
Dor Aguda , Alvéolo Seco , Humanos , Dente Serotino/cirurgia , Dor Aguda/tratamento farmacológico , Corticosteroides/uso terapêutico , Complicações Pós-Operatórias , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia
18.
IEEE Trans Biomed Eng ; 70(12): 3449-3460, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37347631

RESUMO

The present article proposes an ECG simulator that advances modeling of arrhythmias and noise by introducing time-varying signal characteristics. The simulator is built around a discrete-time Markov chain model for simulating atrial and ventricular arrhythmias of particular relevance when analyzing atrial fibrillation (AF). Each state is associated with statistical information on episode duration and heartbeat characteristics. Statistical, time-varying modeling of muscle noise, motion artifacts, and the influence of respiration is introduced to increase the complexity of simulated ECGs, making the simulator well suited for data augmentation in machine learning. Modeling of how the PQ and QT intervals depend on heart rate is also introduced. The realism of simulated ECGs is assessed by three experienced doctors, showing that simulated ECGs are difficult to distinguish from real ECGs. Simulator usefulness is illustrated in terms of AF detection performance when either simulated or real ECGs are used to train a neural network for signal quality control. The results show that both types of training lead to similar performance.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/diagnóstico , Frequência Cardíaca , Simulação por Computador , Eletrocardiografia/métodos , Redes Neurais de Computação
19.
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
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