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1.
Nat Biomed Eng ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698155

RESUMO

The adenovirus-mediated somatic transfer of the embryonic T-box transcription factor 18 (TBX18) gene can convert chamber cardiomyocytes into induced pacemaker cells. However, the translation of therapeutic TBX18-induced cardiac pacing faces safety challenges. Here we show that the myocardial expression of synthetic TBX18 mRNA in animals generates de novo pacing and limits innate and inflammatory immune responses. In rats, intramyocardially injected mRNA remained localized, whereas direct myocardial injection of an adenovirus carrying a reporter gene resulted in diffuse expression and in substantial spillover to the liver, spleen and lungs. Transient expression of TBX18 mRNA in rats led to de novo automaticity and pacemaker properties and, compared with the injection of adenovirus, to substantial reductions in the expression of inflammatory genes and in activated macrophage populations. In rodent and clinically relevant porcine models of complete heart block, intramyocardially injected TBX18 mRNA provided rate-adaptive cardiac pacing for one month that strongly correlated with the animal's sinus rhythm and physical activity. TBX18 mRNA may aid the development of biological pacemakers.

2.
Int J Biostat ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38590225

RESUMO

Many cohort studies in survival analysis have imbedded in them subcohorts consisting of incident cases and prevalent cases. Instead of analysing the data from the incident and prevalent cohorts alone, there are surely advantages to combining the data from these two subcohorts. In this paper, we discuss a survival function nonparametric maximum likelihood estimator (NPMLE) using both length-biased right-censored prevalent cohort data and right-censored incident cohort data. We establish the asymptotic properties of the survival function NPMLE and utilize the NPMLE to estimate the distribution for time spent in a Montreal area hospital.

3.
Telemed J E Health ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621152

RESUMO

Objective: We examined the change in pediatric primary care clinician attitudes and perceptions about telemedicine after one year of telemedicine use. Methods: We administered a survey to pediatric primary care clinicians across 50 primary care practices in Pennsylvania in 2020 and 2021. Surveys were linked using a combination of deterministic and probabilistic matching. We used McNemar's test to compare change in responses from 2020 to 2021. Results: Among pediatric primary care clinicians surveyed in 2020 and 2021 (n = 101), clinicians agreed that telemedicine could always or usually deliver high-quality care for mental health (80% in 2020 and 78% in 2021), care coordination (77% in 2020 and 70% in 2021), acute care (33% in 2020 and 34% in 2021), or preventive care (25% in 2020 and 18% in 2021) and this did not significantly change. Clinician perceptions of usability, while high, declined over time with fewer endorsing ease of use (93% in 2020 and 80% in 2021) and reliability (14% in 2020 and 0% in 2021) over time. Despite this, 62% of clinicians agreed that they were satisfied with their use of telemedicine at both time points. Respondents anticipated positive impact on equity and timeliness of care from telemedicine use but did not anticipate positive impact across child health, health care delivery, or clinician experience. Perceptions across these domains did not change over time. Conclusions: With one year of telemedicine experience, primary care clinicians maintained beliefs that telemedicine could deliver high-quality care for specific clinical needs but had worsening perceptions of usability over time.

4.
J Mech Behav Biomed Mater ; 152: 106434, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350383

RESUMO

The reliability of computational models in orthopedic biomechanics depends often on the accuracy of the bone material properties. It is widely recognized that the mechanical response of trabecular bone is time-dependent, yet it is often ignored for the sake of simplicity. Previous investigations into the viscoelastic properties of trabecular bone have not explored the relationship between nonlinear stress relaxation and bone mineral density. The inclusion of this behavior could enhance the accuracy of simulations of orthopedic interventions, such as of primary fixation of implants. Although methods to quantify the viscoelastic behavior are known, the time period during which the viscoelastic properties should be investigated to obtain reliable predictions is currently unclear. Therefore, this study aimed to: 1) Investigate the duration of stress relaxation in bovine trabecular bone; 2) construct a material model that describes the nonlinear viscoelastic behavior of uniaxial stress relaxation experiments on trabecular bone; and 3) implement bone density into this model. Uniaxial compressive stress relaxation experiments were performed with cylindrical bovine femoral trabecular bone samples (n = 16) with constant strain held for 24 h. Additionally, multiple stress relaxation experiments with four ascending strain levels with a holding time of 30 min, based on the results of the 24-h experiment, were executed on 18 bovine bone cores. The bone specimens used in this study had a mean diameter of 12.80 mm and a mean height of 28.70 mm. A Schapery and a Superposition model were used to capture the nonlinear stress relaxation behavior in terms of applied strain level and bone mineral density. While most stress relaxation happened in the first 10 min (up to 53 %) after initial compression, the stress relaxation continued even after 24 h. Up to 69 % of stress relaxation was observed at 24 h. Extrapolating the results of 30 min of experimental data to 24 h provided a good fit for accuracy with much improved experimental efficiency. The Schapery and Superposition model were both capable of fitting the repeated stress relaxation in a sample-by-sample approach. However, since bone mineral density did not influence the time-dependent behavior, only the Superposition model could be used for a group-based model fit. Although the sample-by-sample approach was more accurate for an individual specimen, the group based approach is considered a useful model for general application.


Assuntos
Densidade Óssea , Osso Esponjoso , Bovinos , Animais , Reprodutibilidade dos Testes , Fenômenos Biomecânicos , Fêmur
5.
Sci Rep ; 14(1): 2243, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278855

RESUMO

Cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) possess tremendous potential for basic research and translational application. However, these cells structurally and functionally resemble fetal cardiomyocytes, which is a major limitation of these cells. Microgravity can significantly alter cell behavior and function. Here we investigated the effect of simulated microgravity on hiPSC-CM maturation. Following culture under simulated microgravity in a random positioning machine for 7 days, 3D hiPSC-CMs had increased mitochondrial content as detected by a mitochondrial protein and mitochondrial DNA to nuclear DNA ratio. The cells also had increased mitochondrial membrane potential. Consistently, simulated microgravity increased mitochondrial respiration in 3D hiPSC-CMs, as indicated by higher levels of maximal respiration and ATP content, suggesting improved metabolic maturation in simulated microgravity cultures compared with cultures under normal gravity. Cells from simulated microgravity cultures also had improved Ca2+ transient parameters, a functional characteristic of more mature cardiomyocytes. In addition, these cells had improved structural properties associated with more mature cardiomyocytes, including increased sarcomere length, z-disc length, nuclear diameter, and nuclear eccentricity. These findings indicate that microgravity enhances the maturation of hiPSC-CMs at the structural, metabolic, and functional levels.


Assuntos
Células-Tronco Pluripotentes Induzidas , Ausência de Peso , Humanos , Miócitos Cardíacos/metabolismo , Células Cultivadas , Sarcômeros , Diferenciação Celular
6.
Stem Cell Res Ther ; 14(1): 322, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37941041

RESUMO

BACKGROUND: Cardiac pathological outcome of metabolic remodeling is difficult to model using cardiomyocytes derived from human-induced pluripotent stem cells (hiPSC-CMs) due to low metabolic maturation. METHODS: hiPSC-CM spheres were treated with AMP-activated protein kinase (AMPK) activators and examined for hiPSC-CM maturation features, molecular changes and the response to pathological stimuli. RESULTS: Treatment of hiPSC-CMs with AMPK activators increased ATP content, mitochondrial membrane potential and content, mitochondrial DNA, mitochondrial function and fatty acid uptake, indicating increased metabolic maturation. Conversely, the knockdown of AMPK inhibited mitochondrial maturation of hiPSC-CMs. In addition, AMPK activator-treated hiPSC-CMs had improved structural development and functional features-including enhanced Ca2+ transient kinetics and increased contraction. Transcriptomic, proteomic and metabolomic profiling identified differential levels of expression of genes, proteins and metabolites associated with a molecular signature of mature cardiomyocytes in AMPK activator-treated hiPSC-CMs. In response to pathological stimuli, AMPK activator-treated hiPSC-CMs had increased glycolysis, and other pathological outcomes compared to untreated cells. CONCLUSION: AMPK activator-treated cardiac spheres could serve as a valuable model to gain novel insights into cardiac diseases.


Assuntos
Proteínas Quinases Ativadas por AMP , Células-Tronco Pluripotentes Induzidas , Humanos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Células Cultivadas , Proteômica , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular/fisiologia
7.
Pediatr Pulmonol ; 58(11): 3179-3187, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37594160

RESUMO

BACKGROUND: We aimed to determine the association of COVID-19 variant wave with asthma exacerbations in children with asthma. METHODS: We conducted a retrospective cross-sectional study of children in the Western Pennsylvania COVID-19 Registry (WPACR). We extracted data for all children in the WPACR with asthma and compared their acute clinical presentation and outcomes during the Pre-Delta (7/1/20-6/30/21), Delta (8/1/21-12/14/21), and Omicron (12/15/21-8/30/22) waves. We conducted multivariable logistic regression analyses of SARS-CoV-2-associated asthma exacerbations, adjusting for characteristics that have been associated with COVID-19 outcomes in prior studies. RESULTS: Among 573 children with asthma in the WPACR during the study period, the proportion of children with COVID-19 who had an asthma exacerbation was higher during the Omicron wave than during the prior two variant waves (40.2% vs. 22.6% vs. 26.2%, p = 0.002; unadjusted OR = 2.12 [95% confidence interval (CI) = 1.39-3.22], p < 0.001). In our multivariable regression models, the odds of an asthma exacerbation were 2.8 times higher during the Omicron wave than during prior waves (adjusted OR = 2.80 [95% CI = 1.70-4.61]). Results were similar after additionally adjusting for asthma severity but were no longer significant after additionally adjusting for poor asthma control. CONCLUSION: The proportion of children with asthma experiencing an asthma exacerbation during SARS-CoV-2 infection was higher during Omicron than prior variant waves, adding to the body of evidence that COVID-19-associated respiratory symptoms vary by variant. These findings provide additional support for vaccination and prevention.


Assuntos
Asma , COVID-19 , Humanos , Criança , COVID-19/complicações , COVID-19/epidemiologia , SARS-CoV-2 , Estudos Transversais , Estudos Retrospectivos , Asma/complicações , Asma/epidemiologia
8.
Ann Am Thorac Soc ; 20(11): 1605-1613, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37495209

RESUMO

Rationale: Little is known about the long-term impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on children with asthma. Objectives: To determine whether SARS-CoV-2 infection affects symptom control and lung function in children with asthma. Methods: Using data from clinical registries and the electronic health record, we conducted a prospective case-control study of children with asthma aged 6-21 years who had (cases) or did not have (control subjects) SARS-CoV-2 infection, comparing baseline and follow-up asthma symptom control and spirometry within an ∼18-month time frame and, for cases, within 18 months of acute coronavirus disease (COVID-19). Results: A total of 171 cases had baseline and follow-up asthma symptom data, and 114 cases had baseline and follow-up spirometry measurements. There were no significant differences in asthma symptom control (P = 0.50), forced expiratory volume in 1 second (P = 0.47), forced vital capacity (P = 0.43), forced expiratory volume in 1 second/forced vital capacity (P = 0.43), or forced expiratory flow, midexpiratory phase (P = 0.62), after SARS-CoV-2 infection. Compared with control subjects (113 with symptom data and 237 with spirometry data), there were no significant differences in follow-up asthma symptom control or lung function. A similar proportion of cases and control subjects had poorer asthma symptom control (17.5% vs. 9.7%; P = 0.07) or worse lung function (29.0% vs. 32.5%; P = 0.50) at follow-up. Patients whose asthma control worsened after COVID-19 had a shorter time to follow-up (3.5 [1.5-7.5] vs. 6.1 [3.1-9.8] mo; P = 0.007) and were more likely to have presented with an asthma exacerbation during COVID-19 (46% vs. 26%; P = 0.04) than those without worse control. Conclusions: We found no significant differences in asthma symptom control or lung function in youth with asthma up to 18 months after acute COVID-19, suggesting that COVID-19 does not affect long-term asthma severity or control in the pediatric population.


Assuntos
Asma , COVID-19 , Adolescente , Humanos , Criança , Estudos de Casos e Controles , SARS-CoV-2 , Asma/complicações , Asma/epidemiologia , Asma/diagnóstico , Volume Expiratório Forçado , Pulmão
9.
Int Stat Rev ; 91(1): 72-87, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37193196

RESUMO

Non-parametric estimation of the survival function using observed failure time data depends on the underlying data generating mechanism, including the ways in which the data may be censored and/or truncated. For data arising from a single source or collected from a single cohort, a wide range of estimators have been proposed and compared in the literature. Often, however, it may be possible, and indeed advantageous, to combine and then analyze survival data that have been collected under different study designs. We review non-parametric survival analysis for data obtained by combining the most common types of cohort. We have two main goals: (i) To clarify the differences in the model assumptions, and (ii) to provide a single lens through which some of the proposed estimators may be viewed. Our discussion is relevant to the meta analysis of survival data obtained from different types of study, and to the modern era of electronic health records.

10.
BMJ Open ; 13(3): e067141, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37001917

RESUMO

INTRODUCTION: There are unmet mental health needs of depressed adolescents and young adults (AYAs) across the USA. Behavioural technology adequately integrated into clinical care delivery has potential to improve care access and efficiency. This multisite randomised controlled trial evaluates how a coach-enhanced digital cognitive behavioural intervention (dCBI) enhances usual care for depressed AYAs in paediatric practices with minority enriched samples. METHODS AND ANALYSIS: Participants (n=750) ages 16-22 who meet threshold criteria for depressive severity (Patient Health Questionnaire-9; PHQ-9 score 10-24) will be recruited through paediatric practices across three academic institutions (Boston, Pittsburgh and San Diego). Participants will be randomised to 12 weeks of dCBI+treatment as usual (TAU) (n=450) or TAU alone (n=300) in outpatient paediatric practices. Assessments will be completed at baseline, 6 weeks and 12 weeks with the primary outcome being improvement in clinician-rated and self-reported depressive severity (Children's Depression Rating Scale-Revised and PHQ-9) and secondary outcomes being self-reported suicidal ideation (item 9 on PHQ-9), anxiety severity (Generalised Anxiety Disorder), general quality of life (Satisfaction with Life Scale) and general functioning (Children's Global Assessment Scale). The study design is an intent-to-treat mixed effects regression with group, and covariates nested within the sites. ETHICS AND DISSEMINATION: All participants or their parent/guardian (under 18 years or unemancipated) will give informed consent to a study team member. All data are expected to be collected over 18 months. The Institutional Review Board (IRB) is a board at each institution in the United States that reviews and monitors research involving human subjects. IRB approval from the University of Pittsburgh was obtained on 30 November 2021 (STUDY21080150), from the University of California San Diego's Human Research Protection Program IRB on 14 July 2022 (802047), and from the Boston Children's Hospital IRB on 25 October 2022 (P00040987). Full study results are planned to be published within 2 years of initial study recruitment (October 2024). Dissemination of findings will occur in peer-reviewed journals, professional conferences and through reports to participating entities and stakeholders. TRIAL REGISTRATION NUMBER: NCT05159713; ClinicalTrials.gov.


Assuntos
Depressão , Saúde Mental , Humanos , Adulto Jovem , Adolescente , Criança , Adulto , Depressão/terapia , Qualidade de Vida , Ansiedade/terapia , Transtornos de Ansiedade , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Cell Stem Cell ; 30(1): 96-111.e6, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36516837

RESUMO

The efficacy and safety of gene-therapy strategies for indications like tissue damage hinge on precision; yet, current methods afford little spatial or temporal control of payload delivery. Here, we find that tissue-regeneration enhancer elements (TREEs) isolated from zebrafish can direct targeted, injury-associated gene expression from viral DNA vectors delivered systemically in small and large adult mammalian species. When employed in combination with CRISPR-based epigenome editing tools in mice, zebrafish TREEs stimulated or repressed the expression of endogenous genes after ischemic myocardial infarction. Intravenously delivered recombinant AAV vectors designed with a TREE to direct a constitutively active YAP factor boosted indicators of cardiac regeneration in mice and improved the function of the injured heart. Our findings establish the application of contextual enhancer elements as a potential therapeutic platform for spatiotemporally controlled tissue regeneration in mammals.


Assuntos
Elementos Facilitadores Genéticos , Terapia Genética , Coração , Infarto do Miocárdio , Miócitos Cardíacos , Regeneração , Animais , Camundongos , Proliferação de Células , Coração/fisiologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Peixe-Zebra/genética , Terapia Genética/métodos , Regeneração/genética
12.
J Proteome Res ; 21(10): 2277-2292, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36006872

RESUMO

Previously, we reported that heterologous expression of an embryonic transcription factor, Tbx18, reprograms ventricular cardiomyocytes into induced pacemaker cells (Tbx18-iPMs), though the key pathways are unknown. Here, we have used a tandem mass tag proteomic approach to characterize the impact of Tbx18 on neonatal rat ventricular myocytes. Tbx18 expression triggered vast proteome remodeling. Tbx18-iPMs exhibited increased expression of known pacemaker ion channels, including Hcn4 and Cx45 as well as upregulation of the mechanosensitive ion channels Piezo1, Trpp2 (PKD2), and TrpM7. Metabolic pathways were broadly downregulated, as were ion channels associated with ventricular excitation-contraction coupling. Tbx18-iPMs also exhibited extensive intracellular cytoskeletal and extracellular matrix remodeling, including 96 differentially expressed proteins associated with the epithelial-to-mesenchymal transition (EMT). RNAseq extended coverage of low abundance transcription factors, revealing upregulation of EMT-inducing Snai1, Snai2, Twist1, Twist2, and Zeb2. Finally, network diffusion mapping of >200 transcriptional regulators indicates EMT and heart development factors occupy adjacent network neighborhoods downstream of Tbx18 but upstream of metabolic control factors. In conclusion, transdifferentiation of cardiac myocytes into pacemaker cells entails massive electrogenic, metabolic, and cytostructural remodeling. Structural changes exhibit hallmarks of the EMT. The results aid ongoing efforts to maximize the yield and phenotypic stability of engineered biological pacemakers.


Assuntos
Transdiferenciação Celular , Transição Epitelial-Mesenquimal , Miócitos Cardíacos , Proteínas com Domínio T , Animais , Transição Epitelial-Mesenquimal/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Miócitos Cardíacos/metabolismo , Proteoma/metabolismo , Proteômica , Ratos , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Canais de Cátion TRPM/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
13.
J Anim Ecol ; 91(9): 1755-1769, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35852382

RESUMO

Technological advances in the field of animal tracking have greatly expanded the potential to remotely monitor animals, opening the door to exploring how animals shift their behaviour over time or respond to external stimuli. A wide variety of animal-borne sensors can provide information on an animal's location, movement characteristics, external environmental conditions and internal physiological status. Here, we demonstrate how piecewise regression can be used to identify the presence and timing of potential shifts in a variety of biological responses using multiple biotelemetry data streams. Different biological latent states can be inferred by partitioning a time-series into multiple segments based on changes in modelled responses (e.g. their mean, variance, trend, degree of autocorrelation) and specifying a unique model structure for each interval. We provide six example applications highlighting a variety of taxonomic species, data streams, timescales and biological phenomena. These examples include a short-term behavioural response (flee and return) by a trumpeter swan Cygnus buccinator following a GPS collar deployment; remote identification of parturition based on movements by a pregnant moose Alces alces; a physiological response (spike in heart-rate) in a black bear Ursus americanus to a stressful stimulus (presence of a drone); a mortality event of a trumpeter swan signalled by changes in collar temperature and overall dynamic body acceleration; an unsupervised method for identifying the onset, return, duration and staging use of sandhill crane Antigone canadensis migration; and estimation of the transition between incubation and brood-rearing (i.e. hatching) for a breeding trumpeter swan. We implement analyses using the mcp package in R, which provides functionality for specifying and fitting a wide variety of user-defined model structures in a Bayesian framework and methods for assessing and comparing models using information criteria and cross-validation measures. These simple modelling approaches are accessible to a wide audience and offer a straightforward means of assessing a variety of biologically relevant changes in animal behaviour.


Assuntos
Cervos , Animais , Teorema de Bayes , Aves , Cervos/fisiologia , Movimento , Temperatura
14.
Med Eng Phys ; 99: 103734, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35058027

RESUMO

Sufficient primary stability through interference fit is required for bone ingrowth and subsequent long-term fixation of cementless knee replacement implants, and can be evaluated in experimental testing. In this study, primary stability of a novel posterior-stabilized (PS) femoral component (Attune PS) and a contemporary PS component (Triathlon PS) were analyzed, and compared to previous outcomes of cruciate-retaining (CR) implants. Potential bone ingrowth was evaluated by measuring micromotions over the implant-bone interface in six cadaveric femur pairs under two loading conditions using digital image correlation, for a paired comparison of the PS implants. Push-off forces required to achieve implant removal under high-flexion were determined as a measure of implant fixation. Achieved interference fit was determined by reconstructing the implant positions through use of separate implant and resected bone geometries. Lower overall micromotions and a higher average push-off force were measured in the Attune PS implant, indicating increased initial fixation compared to the Triathlon PS design. Interference fit was significantly higher for the Attune PS and was related to lower gait micromotions in Triathlon and overall PS groups. Based on reported clinical results and the comparison with available CR implant results, both PS implants are expected to provide sufficient initial clinical stability.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Fenômenos Biomecânicos , Fêmur/cirurgia , Marcha , Humanos , Articulação do Joelho/cirurgia , Desenho de Prótese , Amplitude de Movimento Articular
15.
BMC Med Res Methodol ; 22(1): 10, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996366

RESUMO

When modelling the survival distribution of a disease for which the symptomatic progression of the associated condition is insidious, it is not always clear how to measure the failure/censoring times from some true date of disease onset. In a prevalent cohort study with follow-up, one approach for removing any potential influence from the uncertainty in the measurement of the true onset dates is through the utilization of only the residual lifetimes. As the residual lifetimes are measured from a well-defined screening date (prevalence day) to failure/censoring, these observed time durations are essentially error free. Using residual lifetime data, the nonparametric maximum likelihood estimator (NPMLE) may be used to estimate the underlying survival function. However, the resulting estimator can yield exceptionally wide confidence intervals. Alternatively, while parametric maximum likelihood estimation can yield narrower confidence intervals, it may not be robust to model misspecification. Using only right-censored residual lifetime data, we propose a stacking procedure to overcome the non-robustness of model misspecification; our proposed estimator comprises a linear combination of individual nonparametric/parametric survival function estimators, with optimal stacking weights obtained by minimizing a Brier Score loss function.


Assuntos
Estudos de Coortes , Simulação por Computador , Humanos , Funções Verossimilhança , Análise de Sobrevida , Incerteza
16.
J Biomed Mater Res B Appl Biomater ; 110(4): 776-786, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34661334

RESUMO

Periprosthetic bone loss is an important factor in tibial implant failure mechanisms in total knee arthroplasty (TKA). The purpose of this study was to validate computational postoperative bone response using longitudinal clinical DEXA densities. Computational remodeling outcome over a population was obtained by incorporating the strain-adaptive remodeling theory in finite element (FE) simulations of 26 different tibiae. Physiological loading conditions were applied, and bone mineral density (BMD) in three different regions of interest (ROIs) was considered over a postoperative time of 15 years. BMD outcome was compared directly to previously reported clinical BMD data of a comparable TKA cohort. Similar trends between computational and clinical bone remodeling over time were observed in the two proximal ROIs, with most rapid bone loss taking place in the initial months after TKA and BMD starting to level in the following years. The extent of absolute proximal BMD change was underestimated in the FE population compared with the clinical subject group, which might be the result of significantly higher initial clinical baseline BMD values. Large differences in remodeling response were found in the distal ROI, in which resorption was measured clinically, but a large BMD increase was predicted by the FE models. Multiple computational limitations, related to the FE mesh, loading conditions, and strain-adaptive algorithm, likely contributed to the extensive local bone formation. Further research incorporating subject-specific comparisons using follow-up CT scans and more extensive physiological knee loading is recommended to optimize bone remodeling more distal to the tibial baseplate.


Assuntos
Artroplastia do Joelho , Absorciometria de Fóton , Densidade Óssea , Remodelação Óssea , Humanos , Tíbia/cirurgia
17.
Pediatr Allergy Immunol ; 33(1): e13696, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775650

RESUMO

BACKGROUND: Most pediatric studies of asthma and COVID-19 to date have been ecological, which offer limited insight. We evaluated the association between asthma and COVID-19 at an individual level. METHODS: Using data from prospective clinical registries, we conducted a nested case-control study comparing three groups: children with COVID-19 and underlying asthma ("A+C" cases); children with COVID-19 without underlying disease ("C+" controls); and children with asthma without COVID-19 ("A+" controls). RESULTS: The cohort included 142 A+C cases, 1110 C+ controls, and 140 A+ controls. A+C cases were more likely than C+ controls to present with dyspnea and wheezing, to receive pharmacologic treatment including systemic steroids (all p < .01), and to be hospitalized (4.9% vs. 1.7%, p = .01). In the adjusted analysis, A+C cases were nearly 4 times more likely to be hospitalized than C+ controls (adjusted OR = 3.95 [95%CI = 1.4-10.9]); however, length of stay and respiratory support level did not differ between groups. Among A+C cases, 8.5% presented with an asthma exacerbation and another 6.3% developed acute exacerbation symptoms shortly after testing positive for SARS-CoV-2. Compared to historic A+ controls, A+C cases had less severe asthma, were less likely to be on controller medications, and had better asthma symptom control (all p < .01). CONCLUSIONS: In our cohort, asthma was a risk factor for hospitalization in children with COVID-19, but not for worse COVID-19 outcomes. SARS-CoV-2 does not seem to be a strong trigger for pediatric asthma exacerbations. Asthma severity was not associated with higher risk of COVID-19.


Assuntos
Asma , COVID-19 , Asma/tratamento farmacológico , Asma/epidemiologia , Estudos de Casos e Controles , Criança , Hospitalização , Humanos , Estudos Prospectivos , Fatores de Risco , SARS-CoV-2
18.
Circ Arrhythm Electrophysiol ; 14(10): e009957, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34592837

RESUMO

Each heartbeat that pumps blood throughout the body is initiated by an electrical impulse generated in the sinoatrial node (SAN). However, a number of disease conditions can hamper the ability of the SAN's pacemaker cells to generate consistent action potentials and maintain an orderly conduction path, leading to arrhythmias. For symptomatic patients, current treatments rely on implantation of an electronic pacing device. However, complications inherent to the indwelling hardware give pause to categorical use of device therapy for a subset of populations, including pediatric patients or those with temporary pacing needs. Cellular-based biological pacemakers, derived in vitro or in situ, could function as a therapeutic alternative to current electronic pacemakers. Understanding how biological pacemakers measure up to the SAN would facilitate defining and demonstrating its advantages over current treatments. In this review, we discuss recent approaches to creating biological pacemakers and delineate design criteria to guide future progress based on insights from basic biology of the SAN. We emphasize the need for long-term efficacy in vivo via maintenance of relevant proteins, source-sink balance, a niche reflective of the native SAN microenvironment, and chronotropic competence. With a focus on such criteria, combined with delivery methods tailored for disease indications, clinical implementation will be attainable.


Assuntos
Arritmias Cardíacas/terapia , Relógios Biológicos , Nó Sinoatrial/fisiopatologia , Potenciais de Ação/fisiologia , Arritmias Cardíacas/fisiopatologia , Humanos , Desenho de Prótese
19.
Appl Clin Inform ; 12(2): 310-319, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33853141

RESUMO

OBJECTIVE: The study aimed to evaluate an integrated electronic questionnaire system implementation in outpatient community pediatric practices on workflow, completion rates, and recorded scores. METHODS: We evaluated the implementation and outcomes of an integrated electronic questionnaire system at 45 community pediatric practices that used standardized questionnaires to screen for autism, depression, and substance use and to measure asthma control. Electronic health record (EHR) data for all well child visits were extracted for the 3 months before and after implementation. We used statistical process control charts to evaluate questionnaire completion rates and Chi-square tests to evaluate screening completion and positive screening rates. The collection and entry of questionnaire information was observed and timed. RESULTS: EHR data included 107,120 encounters across 45 practices that showed significant and sustained improvement in completion rates for all questionnaires. The rate of recorded concerning questionnaires decreased for asthma control (19.3 vs. 12.8%, p < 0.001), stayed the same for autism (96.6 vs. 96.2%, p = 0.38), decreased for depression (9.5 vs. 6.7%, p ≤ 0.001), and increased for any substance use (9.8 vs. 12.8%, p < 0.001). Twelve practices were observed, and patient time and staff time managing questionnaires were decreased after implementation. DISCUSSION: Electronic questionnaire administration saved staff time and patient time. We report overall improvement in questionnaire completion rates, with notable variation in improvement in completion across practices and in change in concerning recorded result rates across measures. CONCLUSION: Conversion of four standard paper questionnaires to an integrated electronic system reduces patient and staff time while increasing completion rates when well integrated into routine care.


Assuntos
Instituições de Assistência Ambulatorial , Registros Eletrônicos de Saúde , Criança , Eletrônica , Humanos , Inquéritos e Questionários , Fluxo de Trabalho
20.
Acad Pediatr ; 21(7): 1239-1243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33741531

RESUMO

OBJECTIVE: Regulatory and payment changes associated with COVID-19 facilitated wide-spread use of telehealth within pediatric primary care starting in March 2020. Given prior quality concerns about antibiotic management for children during telemedicine visits outside of primary care, we sought to examine acute respiratory tract infection (ARTI) visit volume and antibiotic management for children via telemedicine integrated within pediatric primary care. METHODS: Using electronic health record data from 47 practices within a large pediatric primary care network, we identified visits for ARTI from April to September 2020. For these visits, we categorized antibiotic management consistent with clinical guidelines as guideline concordant. We compared telemedicine and in-person visit guideline-concordant antibiotic management, diagnoses, and antibiotic prescribing using chi-square tests and examined trends over time using descriptive statistics. Antibiotic stewardship during the study period included learning collaborative videoconferences and sharing of clinic and clinician-level metrics through an interactive dashboard. RESULTS: During the 6-month period, 8332 ARTI visits were identified, with 3003 (36%) via telemedicine. Guideline-concordant antibiotic management occurred in 92.5% of telemedicine visits compared to 90.7% of in-person office visits (P = .004). Telemedicine ARTI visits receiving diagnoses of acute otitis media or streptococcal pharyngitis declined from peak of 52% (May) to 7% (September). Guideline-concordant antibiotic management of sinusitis and viral ARTI during telemedicine visits increased from 88% (April) to 97% (September). CONCLUSION: With active antibiotic stewardship, pediatricians practicing within certified medical homes consistently delivered highly guideline-concordant care for ARTIs to their patient population via telemedicine integrated into primary care.


Assuntos
COVID-19 , Infecções Respiratórias , Telemedicina , Antibacterianos/uso terapêutico , Criança , Humanos , Padrões de Prática Médica , Atenção Primária à Saúde , Infecções Respiratórias/tratamento farmacológico , SARS-CoV-2
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