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1.
Artigo em Inglês | MEDLINE | ID: mdl-38768264

RESUMO

Freestanding single-crystalline SrTiO3 membranes, as high-κ dielectrics, hold significant promise as the gate dielectric in two-dimensional (2D) flexible electronics. Nevertheless, the mechanical properties of the SrTiO3 membranes, such as elasticity, remain a critical piece of the puzzle to adequately address the viability of their applications in flexible devices. Here, we report statistical analysis on plane-strain effective Young's modulus of large-area SrTiO3 membranes (5 × 5 mm2) over a series of thicknesses (from 6.5 to 32.2 nm), taking advantage of a highly efficient buckling-based method, which reveals its evident thickness-dependent behavior ranging from 46.01 to 227.17 GPa. Based on microscopic and theoretical results, we elucidate these thickness-dependent behaviors and statistical data deviation with a bilayer model, which consists of a surface layer and a bulk-like layer. The analytical results show that the ∼3.1 nm surface layer has a significant elastic softening compared to the bulk-like layer, while the extracted modulus of the bulk-like layer shows a variation of ∼40 GPa. This variation is considered as a combined contribution from oxygen deficiency presenting in SrTiO3 membranes, and the alignment between applied strain and the crystal orientation. Upon comparison of the extracted elastic properties and electrostatic control capability to those of other typical gate dielectrics, the superior performance of single-crystalline SrTiO3 membranes has been revealed in the context of flexible gate dielectrics, indicating the significant potential of their application in high-performance flexible 2D electronics.

2.
Front Public Health ; 12: 1367546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560430

RESUMO

Background: Organ and Tissue Donation Coordinators (OTDCs) are key to the success of deceased organ donation processes. However, reduced resilience can leave them susceptible to the incidence of work-related issues and decrease the quality of the care provided. Therefore, this study aimed to examine the extent of resilience and influencing aspects among OTDCs in Canada. Methods: Mixed-method (QUAN-qual) explanatory sequential design. Quantitative data was collected using an online cross-sectional survey approach with demographic data and the validated scales and analyzed using descriptive and inferential statistics. Qualitative data was collected using a descriptive approach with a semi-structured interview guide and analyzed using content analysis. Results: One hundred twenty participants responded to the survey, and 39 participants were interviewed. Most participants from the survey were female (82%), registered nurses (97%) and on average 42 years old. The quantitative data revealed that OTDCs had a high level of perceived compassion satisfaction (ProQOL-CS = 36.3) but a resilience score (CD-RISC = 28.5) lower than other groups of healthcare professionals. OTDCs with over a year of experience in the role were more likely to have higher levels of resilience. The qualitative data identified that participants saw resilience as crucial for their work-related well-being. Although coping strategies were identified as a key factor that enhance resilience, many OTDCs reported difficulty in developing healthy coping strategies, and that the use of unhealthy mechanisms (e.g., alcohol and smoking) can result in negative physical consequences (e.g., weight gain) and reduced resilience levels. Conclusion: Participants reported using a series of coping and protective strategies to help build resilience, but also difficulty in developing healthy mechanisms. The lack of healthy coping strategies were seen as contributing to negative work-related issues (e.g., burnout). Our findings are being used to develop tailored interventions to improve resilience and healthy coping strategies among organ donor coordinators in Canada.


Assuntos
Testes Psicológicos , Resiliência Psicológica , Obtenção de Tecidos e Órgãos , Humanos , Feminino , Adulto , Masculino , Estudos Transversais , Canadá
3.
Anesthesiology ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684054

RESUMO

BACKGROUND: Adenotonsillectomy and tonsillectomy (now referred to as tonsillectomy thereafter) are common pediatric surgeries. Postoperative complications include hemorrhage requiring surgery (2-3% of cases) and pain. While non-steroidal anti-inflammatory drugs are commonly administered for post-surgical pain, controversy exists regarding bleeding risk with cyclo-oxygenase-1 inhibition and associated platelet dysfunction. Preliminary evidence suggests selective cyclo-oxygenase-2 inhibitors, for example celecoxib, effectively manage pain without adverse events including bleeding. Given the paucity of data for routine celecoxib use after tonsillectomy, we investigated the association between post-operative celecoxib prescription and post-tonsillectomy hemorrhage requiring surgery using chart-review data from the Children's Hospital of Eastern Ontario, Canada. METHODS: After ethics approval we performed a retrospective single-center observational cohort study in children <18 yrs undergoing tonsillectomy from January 2007 to December 2017. Cases of adenoidectomy alone were excluded due to low bleed rates. The primary outcome was the proportion of patients with post-tonsillectomy hemorrhage requiring surgery. The association between a celecoxib prescription and post-tonsillectomy hemorrhage requiring surgery was estimated using inverse probability of treatment weighting based on propensity scores and using generalized estimating equations to accommodate clustering by surgeon. RESULTS: An initial patient cohort of 6468 was identified and 5846 children with complete data were included in analyses. Median (interquartile range) age was 6.10 (4.40, 9.00) years and 46% were female. In our cohort, 28.1% (n=1644) were prescribed celecoxib. Among the 4996 tonsillectomy patients, 1.7% (n=86) experienced post-tonsillectomy hemorrhage requiring surgery. The proportion with post-tonsillectomy hemorrhage requiring surgery among patients who had a tonsillectomy and were or were not prescribed celecoxib was 1.94% (30/1548; 95% CI: 1.36-2.75) and 1.62% (56/3448; 95% CI: 1.25-2.10), respectively. Modelling did not identify an association between celecoxib prescription and increased odds of post-tonsillectomy hemorrhage requiring surgery (OR=1.4, 95% CI: 0.85-2.31, p=0.20). CONCLUSIONS: Celecoxib does not significantly increase the odds of post-tonsillectomy hemorrhage requiring surgery, after adjusting for covariates. This large pediatric cohort study of celecoxib administered after tonsillectomy provides compelling evidence for safety but requires confirmation with a multi-site randomized controlled trial.

4.
AJNR Am J Neuroradiol ; 45(5): 588-591, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38548309

RESUMO

Pediatric large-vessel occlusion has a poor natural history. Recent retrospective studies have demonstrated the potential benefits, feasibility, and safety profile of mechanical thrombectomy in children. However, the role of thrombectomy in pediatric M2 occlusions remains uncertain. In this clinical report, we present a multicenter series of 6 pediatric patients with acute M2 occlusion (female = 1, male = 5; age range, 0.9-16.0 years, mean = 9.2). All 6 patients having undergone thrombectomy had excellent clinical outcomes (pediatric mRS = 0-1) at 3 months and final available follow-up (median, 12 months; range, 3-72 months). Factors relevant to treatment decision-making in pediatric M2 occlusions are discussed, including the important role of multidisciplinary team discussions during acute management.


Assuntos
AVC Isquêmico , Trombectomia , Humanos , Criança , Masculino , Feminino , Adolescente , AVC Isquêmico/cirurgia , AVC Isquêmico/diagnóstico por imagem , Pré-Escolar , Trombectomia/métodos , Lactente , Resultado do Tratamento , Estudos Retrospectivos
5.
Cell Mol Life Sci ; 81(1): 129, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472514

RESUMO

Recent work putatively linked a rare genetic variant of the chaperone Resistant to Inhibitors of acetylcholinesterase (RIC3) (NM_024557.4:c.262G > A, NP_078833.3:p.G88R) to a unique ability to speak backwards, a language skill that is associated with exceptional working memory capacity. RIC3 is important for the folding, maturation, and functional expression of α7 nicotinic acetylcholine receptors (nAChR). We compared and contrasted the effects of RIC3G88R on assembly, cell surface expression, and function of human α7 receptors using fluorescent protein tagged α7 nAChR and Förster resonance energy transfer (FRET) microscopy imaging in combination with functional assays and 125I-α-bungarotoxin binding. As expected, the wild-type RIC3 protein was found to increase both cell surface and functional expression of α7 receptors. In contrast, the variant form of RIC3 decreased both. FRET analysis showed that RICG88R increased the interactions between RIC3 and α7 protein in the endoplasmic reticulum. These results provide interesting and novel data to show that a RIC3 variant alters the interaction of RIC3 and α7, which translates to decreased cell surface and functional expression of α7 nAChR.


Assuntos
Receptores Nicotínicos , Humanos , Acetilcolinesterase/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Membrana Celular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Receptores Nicotínicos/genética , Fala
6.
Neurology ; 102(5): e208112, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38335499

RESUMO

BACKGROUND AND OBJECTIVES: Vamorolone is a dissociative agonist of the glucocorticoid receptor that has shown similar efficacy and reduced safety concerns in comparison with prednisone in Duchenne muscular dystrophy (DMD). This study was conducted to determine the efficacy and safety of vamorolone over 48 weeks and to study crossover participants (prednisone to vamorolone; placebo to vamorolone). METHODS: A randomized, double-blind, placebo-controlled and prednisone-controlled clinical trial of 2 doses of vamorolone was conducted in participants with DMD, in the ages from 4 years to younger than 7 years at baseline. The interventions were 2 mg/kg/d of vamorolone and 6 mg/kg/d of vamorolone for 48 weeks (period 1: 24 weeks + period 2: 24 weeks) and 0.75 mg/kg/d of prednisone and placebo for the first 24 weeks (before crossover). Efficacy was evaluated through gross motor outcomes and safety through adverse events, growth velocity, body mass index (BMI), and bone turnover biomarkers. This analysis focused on period 2. RESULTS: A total of 121 participants with DMD were randomized. Vamorolone at a dose of 6 mg/kg/d showed maintenance of improvement for all motor outcomes to week 48 (e.g., for primary outcome, time to stand from supine [TTSTAND] velocity, week 24 least squares mean [LSM] [SE] 0.052 [0.0130] rises/s vs week 48 LSM [SE] 0.0446 [0.0138]). After 48 weeks, vamorolone at a dose of 2 mg/kg/d showed similar improvements as 6 mg/kg/d for North Star Ambulatory Assessment (NSAA) (vamorolone 6 mg/kg/d-vamorolone 2 mg/kg/d LSM [SE] 0.49 [1.14]; 95% CI -1.80 to 2.78, p = 0.67), but less improvement for other motor outcomes. The placebo to vamorolone 6 mg/kg/d group showed rapid improvements after 20 weeks of treatment approaching benefit seen with 48-week 6 mg/kg/d of vamorolone treatment for TTSTAND, time to run/walk 10 m, and NSAA. There was significant improvement in linear growth after crossover in the prednisone to vamorolone 6 mg/kg/d group, and rapid reversal of prednisone-induced decline in bone turnover biomarkers in both crossover groups. There was an increase in BMI after 24 weeks of treatment that then stabilized for both vamorolone groups. DISCUSSION: Improvements of motor outcomes seen with 6 mg/kg/d of vamorolone at 24 weeks of treatment were maintained to 48 weeks of treatment. Vamorolone at a dose of 6 mg/kg/d showed better maintenance of effect compared with vamorolone at a dose of 2 mg/kg/d for most (3/5) motor outcomes. Bone morbidities of prednisone (stunting of growth and declines in serum bone biomarkers) were reversed when treatment transitioned to vamorolone. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov Identifier: NCT03439670. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that for boys with DMD, the efficacy of vamorolone at a dose of 6 mg/kg/d was maintained over 48 weeks.


Assuntos
Distrofia Muscular de Duchenne , Pregnadienodiois , Humanos , Masculino , Biomarcadores , Distrofia Muscular de Duchenne/tratamento farmacológico , Prednisona/efeitos adversos , Pregnadienodiois/efeitos adversos , Pré-Escolar , Criança
7.
Anal Methods ; 16(9): 1323-1329, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38189186

RESUMO

Two new techniques for analyzing praziquantel (PZQ), an effective antiparasitic drug used in fresh and saltwater aquariums, were optimized and compared. One method was based on voltammetry and the other method used gas chromatography combined with mass spectrometry (GC-MS), although both procedures utilized the same sample pretreatment strategy which involved the PZQ being quantitatively transferred into acetonitrile using solid phase extraction. GC-MS analysis led to lower limits of detection (0.32 µM, 0.10 ppm) and quantification (0.72 µM, 0.22 ppm) compared to voltammetry, although both methods gave acceptable quantification for levels of PZQ > 25 µM (7.8 ppm). GC-MS is preferred for the most accurate determination, but voltammetry may provide a cost-effective alternative for detecting PZQ where on site testing is required.


Assuntos
Praziquantel , Espectrometria de Massas em Tandem , Praziquantel/química , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem/métodos , Água Doce
8.
Respir Care ; 69(4): 387-394, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38164568

RESUMO

BACKGROUND: Pulse oximetry measurement is ubiquitous in acute health care settings in high-income countries and is familiar to any parent whose child has been treated in such a setting. Oximeters for home use are readily available online and are incorporated in several smartphones and smartwatches. METHODS: We wished to determine how accurate are oximeters available online that are designated for adult and pediatric use, and the saturation monitor integrated in a smartphone, when used in children, compared to reference, hospital-grade oximeters. We evaluated a fingertip oximeter marketed for children purchased online; an adult fingertip oximeter purchased online; the oximeter integrated in a smartphone; and reference, hospital-grade oximeters. Participants were < 18 y of age. Bland-Altman charts were generated, and the estimated root mean square error (EARMS) was calculated. Rates of failure to obtain a measurement, relationship between device and time to successful measurement, relationship between age and time to successful measurement, and relationship between error (vs the reference device) and age were evaluated for each consumer-grade device. RESULTS: We measured SpO2 in 74 children between 0.1-17.0 y of age. Subjects weighing < 30 kg had a median (interquartile range [IQR]) age of 2 (1.0 month-1.4 y) months, and subjects weighing ≥ 30 kg had a median (IQR) age of 14.3 (11.9-16.2) y. Readings could not be obtained in 7.5, 0, and 38.8% of subjects using the pediatric, adult, and smartphone oximeters, respectively. The time to successful reading had a modest negative correlation with age with the inexpensive adult and pediatric oximeters. The inexpensive pediatric oximeter had an overall negative bias, with a mean difference from the reference device of -4.5% (SD 7.9%) and an error that ranged from > 8% to < 33% the reference device. The EARMS was 7.92%. The inexpensive adult oximeter demonstrated no obvious trend in error in the limited saturation range evaluated of 87-99%. The overall mean difference was -0.7% (SD 2.5%). EARMS was 2.5%. The smartphone oximeter underestimated SpO2 at saturations < 94% and overestimated SpO2 for saturations > 94%. Saturations could read as much as > 4%, or < 17%, than the reference oximeter. The mean difference was -2.9% (SD 5.2%). EARMS was 5.1%. CONCLUSIONS: Our findings suggest that the performance of consumer-grade devices varies considerably by both subject age and device. The pediatric fingertip device and smartphone application we tested are poorly suited for use in infants. The adult fingertip device we tested performed quite well in larger children with relatively normal oxygen saturations, and the pediatric fingertip device performed moderately well in subjects > 1 y of age who weighed < 30 kg. Given the vast number of devices available online and ever-changing technology, research to evaluate nonclinical oximeters will continue to be required.


Assuntos
Aplicativos Móveis , Saturação de Oxigênio , Lactente , Adulto , Humanos , Criança , Oxigênio , Oximetria , Smartphone
9.
Can J Neurol Sci ; 51(2): 196-202, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36847175

RESUMO

BACKGROUND: E-learning has become commonplace in medical education. Incorporation of multimedia, clinical cases, and interactive elements has increased its attractiveness over textbooks. Although there has been an expansion of e-learning in medicine, the feasibility of e-learning in pediatric neurology is unclear. This study evaluates knowledge acquisition and satisfaction using pediatric neurology e-learning compared to conventional learning. METHODS: Residents of Canadian pediatrics, neurology, and pediatric neurology programs and medical students from Queens University, Western University, and the University of Ottawa were invited to participate. Learners were randomly assigned two review papers and two ebrain modules in a four-topic crossover design. Participants completed pre-tests, experience surveys, and post-tests. We calculated the median change in score from pre-test to post-test and constructed a mixed-effects model to determine the effect of variables on post-test scores. RESULTS: In total, 119 individuals participated (53 medical students; 66 residents). Ebrain had a larger positive change than review papers in post-test score from pre-test score for the pediatric stroke learning topic but a smaller positive change for Duchenne muscular dystrophy, childhood absence epilepsy, and acute disseminated encephalomyelitis. Learning topics showed statistical relationship to post-test scores (p = 0.04). Depending on topic, 57-92% (N = 59-66) of respondents favored e-learning over review article learning. CONCLUSIONS: Ebrain users scored higher on post-tests than review paper users. However, the effect is small and it is unclear if it is educationally meaningful. Although the difference in scores may not be substantially different, most learners preferred e-learning. Future projects should focus on improving the quality and efficacy of e-learning modules.


Assuntos
Instrução por Computador , Educação Médica , Neurologia , Pediatria , Humanos , Canadá , Neurologia/educação , Estudantes de Medicina , Estudos Cross-Over , Pediatria/educação
10.
Child Neuropsychol ; 30(3): 425-443, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37144751

RESUMO

To (i) determine whether accelerated long-term forgetting (ALF) can be found using standardized verbal memory test materials in children with genetic generalized epilepsy (GGE) and temporal lobe epilepsy (TLE), and (ii) to establish whether ALF is impacted by executive skills and repeat testing over long delays. One hundred and twenty-three children aged 8 to 16, (28 with GGE, 23 with TLE, and 72 typically developing; TD) completed a battery of standardized tests assessing executive functioning and memory for two stories. Stories were recalled immediately and after a 30-min delay. To examine whether repeat testing impacts long-term forgetting, one story was tested via free recall at 1-day and 2-weeks, and the other at 2-weeks only. Recognition was then tested for both stories at 2-weeks. Children with epilepsy recalled fewer story details, both immediately and after 30-min relative to TD children. Compared to TD children, the GGE group, but not the TLE group, showed ALF, having significantly poorer recall of the story tested only at the longest delay. Poor executive skills were significantly correlated with ALF for children with epilepsy. Standard story memory materials can detect ALF in children with epilepsy when administered over long delays. Our findings suggest that (i) ALF is related to poor executive skills in children with epilepsy, and (ii) repeated testing may ameliorate ALF in some children.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Criança , Humanos , Transtornos da Memória , Testes Neuropsicológicos , Memória de Longo Prazo , Memória , Epilepsia/complicações , Rememoração Mental
11.
Infect Control Hosp Epidemiol ; 45(2): 253-256, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37728055

RESUMO

Family caregivers are essential inpatient pediatric care partners, yet their handwashing knowledge and compliance are rarely studied. Through hand hygiene audits and self-administered questionnaires, we observed 9% compliance, significantly lower than self-reported practice. We suggest interventions to improve caregiver handwashing behaviors to decrease infection transmission risk to hospitalized children.


Assuntos
Higiene das Mãos , Humanos , Criança , Cuidadores , Pacientes Internados , Desinfecção das Mãos , Inquéritos e Questionários
12.
Child Care Health Dev ; 50(1): e13169, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658639

RESUMO

BACKGROUND: Currently, there are no standardized approaches to care or evaluation for tone dysfunction in Canada. The study authors hypothesize that there is significant practice variation across the country. This environmental scan is aimed to describe the current practice for management of paediatric patients with hypertonia across Canada. METHODS: A web-based survey was developed by the authors with a multi-disciplinary approach and sent to representative paediatric rehabilitation sites in each province in Canada. Disciplines at the rehabilitation sites surveyed included all or some of the following disciplines: physiatry, neurology, neurosurgery, plastic surgery, orthopaedic surgery, physiotherapy and occupational therapy. All statistical analyses were performed using the R statistical software version 4.0. Fifteen rehabilitation sites were contacted, and 12 sites were used for the final analysis. RESULTS: Cerebral palsy was found to be the most common diagnosis for tone dysfunction, with 58% of sites diagnosing greater than 20 new patients per year. In 67% of sites, patients were seen within a formal multidisciplinary clinic to manage hypertonia. All 12 sites utilized oral baclofen and gabapentin, and 92% of sites utilized trihexyphenidyl. Botulinum toxin injections were offered at 50% of sites. Upper and lower extremity surgical procedures were offered in 83% of the sites. CONCLUSION: The information gained from this study provides some insight into the current practice across Canada for children with hypertonia. This study may assist in the development of a national, standardized strategy to tone management, potentially facilitating more equitable access to care for patients.


Assuntos
Baclofeno , Paralisia Cerebral , Criança , Humanos , Hipertonia Muscular , Gabapentina , Canadá
13.
Seizure ; 115: 1-13, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160512

RESUMO

OBJECTIVES: To determine: i) seizure recurrence; ii) developmental disability; iii) co-morbidities and risk factors in self-limited familial neonatal and/or infantile epilepsy (SeLFE) in a multigenerational study. METHODS: Families were retrospectively recruited from epilepsy databases (2021-2022) in 2 paediatric hospitals, Sydney, Australia. Eligible families had 2 first degree relatives with seizures and underwent genetic testing. Demographics/clinical data were collected from interviews and medical records. Vineland Adaptive Behaviour Scales-Third Edition measured adaptive function. RESULTS: Fifteen families participated. Fourteen had a genetic diagnosis (93%): 11 pathogenic; PRRT2 (n=4), KCNQ2 (n=3), SCN2A (n=4), 3 likely pathogenic; KCNQ2 (n=1), SCN8A (n=2). Seizures affected 73 individuals (ages 1-76 years); 30 children and 20 adults had in-depth phenotyping. Ten of 50 individuals (20%) had seizure recurrence, aged 8-65 years. Median time from last neonatal/infantile seizure was 11.8/12.8 years. Predictors of recurrence were high seizure number (p=0.05) and longer treatment duration (p=0.03). Seven children had global developmental delay (GDD): mild (n=4), moderate (n=1) and severe (n=2). Vineland-3 identified 3 had low-average and 3 had mild-moderately impaired functioning. The majority (82%) were average. GDD was associated with older age at last seizure (p=0.03), longer epilepsy duration (p=0.02), and higher number of anti-seizure medications (p=0.05). Four children had speech delay, 5 (10%) had Autism Spectrum Disorder. Paroxysmal kinesiogenic dyskinesia (n=5) occurred in 4 families and hemiplegic migraine (n=8) in 3 families. CONCLUSIONS: Individuals with SeLFE have a small risk of recurrent seizures (20%) and neurodevelopmental disability. Significant predictors are higher seizure number and longer epilepsy duration. Developmental surveillance is imperative.


Assuntos
Transtorno do Espectro Autista , Epilepsia Neonatal Benigna , Epilepsia , Síndromes Epilépticas , Criança , Recém-Nascido , Adulto , Humanos , Epilepsia Neonatal Benigna/genética , Estudos Retrospectivos , Mutação , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Austrália/epidemiologia , Epilepsia/epidemiologia , Epilepsia/genética , Convulsões/epidemiologia , Convulsões/genética
14.
Sci Rep ; 13(1): 17064, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816924

RESUMO

Phyllachora maydis is a fungal pathogen causing tar spot of corn (Zea mays L.), a new and emerging, yield-limiting disease in the United States. Since being first reported in Illinois and Indiana in 2015, P. maydis can now be found across much of the corn growing regions of the United States. Knowledge of the epidemiology of P. maydis is limited but could be useful in developing tar spot prediction tools. The research presented here aims to elucidate the environmental conditions necessary for the development of tar spot in the field and the creation of predictive models to anticipate future tar spot epidemics. Extended periods (30-day windowpanes) of moderate mean ambient temperature (18-23 °C) were most significant for explaining the development of tar spot. Shorter periods (14- to 21-day windowpanes) of moisture (relative humidity, dew point, number of hours with predicted leaf wetness) were negatively correlated with tar spot development. These weather variables were used to develop multiple logistic regression models, an ensembled model, and two machine learning models for the prediction of tar spot development. This work has improved the understanding of P. maydis epidemiology and provided the foundation for the development of a predictive tool for anticipating future tar spot epidemics.


Assuntos
Doenças das Plantas , Zea mays , Estados Unidos/epidemiologia , Zea mays/microbiologia , Doenças das Plantas/microbiologia , Phyllachorales , Illinois/epidemiologia
15.
ACS Nano ; 17(17): 17148-17157, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37656004

RESUMO

Ferroelectrics possess a spontaneous polarization that is switchable by an electric field and is critical for the development of low-energy nanoelectronics and neuromorphic applications. However, apart from a few recent developments, the realization of switchable polarization in metal oxides with simpler structures has been a major challenge. Here, we demonstrate the presence of robust switchable polarization at the level of a single nanocrystallite in magnesium-doped zinc oxide thin films with polar wurtzite crystal structures. Using a combination of high-resolution scanning probe microscopy and spectroscopic techniques, voltage control of the polarization and the coupled electronic transport behavior revealing a giant resistance change of approximately 10000% is unveiled. Time- and frequency-resolved nanoscale measurements provide key insights into the polarization phenomenon and a 9-fold increase in the effective longitudinal piezoelectric coefficient. Our work thus constitutes a crucial step toward validating nanoscale ferroelectricity in polar wurtzites for use in advanced nanoelectronics and memory applications.

16.
Artigo em Inglês | MEDLINE | ID: mdl-37582613

RESUMO

BACKGROUND AND OBJECTIVES: Up to 50% of patients with myasthenia gravis (MG) without acetylcholine receptor antibodies (AChR-Abs) have antibodies to muscle-specific kinase (MuSK). Most MuSK antibodies (MuSK-Abs) are IgG4 and inhibit agrin-induced MuSK phosphorylation, leading to impaired clustering of AChRs at the developing or mature neuromuscular junction. However, IgG1-3 MuSK-Abs also exist in MuSK-MG patients, and their potential mechanisms have not been explored fully. METHODS: C2C12 myotubes were exposed to MuSK-MG plasma IgG1-3 or IgG4, with or without purified agrin. MuSK, Downstream of Kinase 7 (DOK7), and ßAChR were immunoprecipitated and their phosphorylation levels identified by immunoblotting. Agrin and agrin-independent AChR clusters were measured by immunofluorescence and AChR numbers by binding of 125I-α-bungarotoxin. Transcriptomic analysis was performed on treated myotubes. RESULTS: IgG1-3 MuSK-Abs impaired AChR clustering without inhibiting agrin-induced MuSK phosphorylation. Moreover, the well-established pathway initiated by MuSK through DOK7, resulting in ßAChR phosphorylation, was not impaired by MuSK-IgG1-3 and was agrin-independent. Nevertheless, the AChR clusters did not form, and both the number of AChR microclusters that precede full cluster formation and the myotube surface AChRs were reduced. Transcriptomic analysis did not throw light on the pathways involved. However, the SHP2 inhibitor, NSC-87877, increased the number of microclusters and led to fully formed AChR clusters. DISCUSSION: MuSK-IgG1-3 is pathogenic but seems to act through a noncanonical pathway. Further studies should throw light on the mechanisms involved at the neuromuscular junction.


Assuntos
Miastenia Gravis , Receptores Proteína Tirosina Quinases , Humanos , Agrina/farmacologia , Imunoglobulina G , Proteínas Musculares/metabolismo , Miastenia Gravis/tratamento farmacológico , Fosforilação , Receptores Colinérgicos
17.
PLoS One ; 18(8): e0284946, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37594946

RESUMO

BACKGROUND: Children with congenital heart disease (CHD) often have inactive lifestyles and motor skill deficits beginning in infancy. The least active infants continue to be the least active children at school age. Enhancing physical activity and motor development in infancy, at the time of CHD treatment, may prevent inactive lifestyle habits. METHODS: All children being treated, through surgery or catheterization, for congenital heart disease are eligible if they are 3 to 72 months of age at enrollment. The Peabody Motor Development Scales (Version 2) and 7-day accelerometry (Actigraph GT9X Link) assess motor skills and physical activity prior to treatment and 7 weeks, 6 months and 12 months post-treatment. Participants are randomized 3:1 to intervention:control. Until 7 weeks post-treatment, intervention activities focus on regaining pre-treatment mobility and midline crossing. From 7 weeks to 6 months post-treatment, the intervention is individualized to each child's assessment results and is parent-led, delivered at home and play-based. CONCLUSION: This feasibility study will provide essential data for a randomized controlled trial to evaluate play-based, parent-delivered interventions optimized to support age-appropriate physical activity and motor skills among young children with CHD. Preliminary intervention efficacy data will inform an evidence-based sample size calculation, optimize intervention timing, and identify hypotheses on the motor skill-physical activity connection and the impact of play-based, parent-led interventions during recovery from CHD treatment. Long-term, the goal is to optimize motor skill and active lifestyles among young children with CHD, enabling their healthy growth and development and enhancing childhood quality of life. TRIAL REGISTRATION: Clinical trials registration: NCT04619745.


Assuntos
Cardiopatias Congênitas , Comportamento Sedentário , Lactente , Criança , Humanos , Pré-Escolar , Estudos de Viabilidade , Qualidade de Vida , Cardiopatias Congênitas/cirurgia , Exercício Físico , Cateterismo
18.
Pediatr Radiol ; 53(11): 2229-2234, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37553458

RESUMO

BACKGROUND: Image-guided drainage is the management of choice for perforated appendicitis with intra-abdominal abscess/es. However, there is paucity of data regarding the optimal time for intervention in children. OBJECTIVE: The purpose of this study is to assess the relationship between the time from diagnosis of a drainable abscess to abscess drainage (delta time) and the clinical outcome in patients with complicated acute appendicitis. MATERIALS AND METHODS: This is an institutional review board (IRB)-approved retrospective study comprising 80 pediatric patients who had image-guided abscess drainage due to perforated acute appendicitis. Delta time was associated with clinical outcome including length of stay, catheter dwell time, need for additional interventions, and need for tissue plasminogen activator (t-PA). Gamma regression models were used to assess the adjusted effect of delta time on the "length of stay" and "catheter dwell time" using "volume of the largest abscess" and "number of collections" as severity indices. Logistic regression was used to assess the effect of delta time on the "need for the t-PA" and "need for additional interventions." RESULTS: Mean age (SD) was 10.2 (3.8) years. Mean time between diagnosis and intervention (delta time) was 1.5 (1.2) days. There was no evidence that delta time effects the length of stay, catheter dwell time, need for t-PA, and need for additional interventions (P > 0.05). However, there was an association between the number of collections and volume of the largest abscess with length of stay (P = 0.006; P = 0.058), catheter dwell time (P = 0.029; P < 0.001), and need for additional interventions (P = 0.029; P = 0.016). CONCLUSIONS: Our results suggest that time between diagnosis of an appendicitis associated abscess and intervention is not significantly associated with need for tPA, need for additional intervention, drain dwell time, or length of stay.


Assuntos
Abscesso , Apendicite , Humanos , Criança , Abscesso/complicações , Ativador de Plasminogênio Tecidual , Apendicite/complicações , Apendicite/diagnóstico por imagem , Apendicite/cirurgia , Estudos Retrospectivos , Drenagem/métodos , Apendicectomia/métodos , Tempo de Internação
19.
JAMA Neurol ; 80(9): 910-918, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37486670

RESUMO

Importance: Pediatric large vessel occlusion (LVO) stroke has a poor natural history. However, uptake of mechanical thrombectomy is hindered by a lack of clinical trial data in children. A randomized clinical trial is not feasible due to small sample sizes and absence of equipoise. Objective: To evaluate whether pediatric patients with acute LVO stroke who undergo thrombectomy have better clinical outcomes than matched patients managed conservatively. Design, Setting, and Participants: This matched case-control study used pooled stroke registry data from 5 tertiary referral hospitals in Australia and Canada from January 2011 to April 2022. Patients were aged 1 month to younger than 18 years with acute LVO stroke. Pooled data identified 31 thrombectomy patients and 46 control patients. Five patients undergoing thrombectomy with basilar artery occlusion were excluded due to insufficient controls. Using a hierarchal matching system (site of occlusion, age group, side of occlusion, and sex), deidentified consensus matching of patients and controls was undertaken while blinded to clinical outcome. Data were analyzed from July to November 2022. Exposure: In the case cohort, mechanical thrombectomy was undertaken for management of acute LVO stroke. The control cohort received medical treatment only. Main Outcomes and Measures: The primary outcome was the functional clinical status 3 months following stroke, measured by the pediatric modified Rankin Scale (mRS). Clinical outcomes were compared between groups using ordinal regression analysis. Results: Of 52 included patients, 31 (60%) were male, and the mean (SD) age was 10.3 (4.4) years. Matching was achieved for 26 children undergoing thrombectomy with 26 controls. There was no significant difference between groups for site or side of occlusion, age, sex, etiology, thrombolysis status, baseline Alberta Stroke Programme Early CT Score, or time since last seen well to presentation. Patients undergoing thrombectomy had superior clinical outcomes than control patients at 3 months on the pediatric mRS (odds ratio, 3.76; 95% CI, 1.32-10.67; P = .01). These superior outcomes were maintained at final follow-up (odds ratio, 3.65; 95% CI, 1.25-10.68; P = .02). Conclusions and Relevance: In the absence of a randomized clinical trial, this case-control study demonstrates better clinical outcomes with thrombectomy than medical management alone for pediatric patients aged 2 to 18 years with anterior circulation LVO stroke.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Masculino , Criança , Feminino , AVC Isquêmico/cirurgia , AVC Isquêmico/complicações , Isquemia Encefálica/complicações , Estudos de Casos e Controles , Resultado do Tratamento , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia/efeitos adversos , Arteriopatias Oclusivas/complicações , Procedimentos Endovasculares/efeitos adversos
20.
Healthc Manage Forum ; 36(4): 217-223, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37269126

RESUMO

Healthcare decision-makers are becoming increasingly aware that climate change poses significant threats to population health and continued delivery of quality care. Challengingly, responding to climate change requires complex, often expensive, and multi-faceted actions to limit new emissions from worsening climate trajectories, while investing in climate-resilient systems. We present a Climate Resilience Maturity Matrix that brings together both mitigation and adaptation actions into a high-level tool for health leaders, for supporting organizational review, assessment, and decision-making for climate change readiness. This tool is designed to (i) support leaders in Canadian health facilities and regional health authorities in designing mitigation and adaptation roadmaps, (ii) support decision-making for climate change-related strategic planning processes, and (iii) create a high-level overview of organizational readiness. This tool is intended to consolidate key data, provide a clear communication tool, allow for objective rapid baselining, enable system-level gap analysis, facilitate comparability/transparency, and support rapid learning cycles.


Assuntos
Mudança Climática , Atenção à Saúde , Humanos , Canadá
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