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Bioprosthetic heart valves (BHV) fabricated from glutaraldehyde-fixed heterograft tissue, such as bovine pericardium (BP), are widely used for treating heart valve disease, a group of disorders that affects millions. Structural valve degeneration (SVD) of BHV due to both calcification and the accumulation of advanced glycation end products (AGE) with associated serum proteins limits durability. We hypothesized that BP modified with poly-2-methyl-2-oxazoline (POZ) to inhibit protein entry would demonstrate reduced accumulation of AGE and serum proteins, mitigating SVD. In vitro studies of POZ-modified BP demonstrated reduced accumulation of serum albumin and AGE. BP-POZ in vitro maintained collagen microarchitecture per two-photon microscopy despite AGE incubation, and in cell culture studies was associated with no change in tumor necrosis factor-α after exposure to AGE and activated macrophages. Comparing POZ and polyethylene glycol (PEG)-modified BP in vitro, BP-POZ was minimally affected by oxidative conditions, whereas BP-PEG was susceptible to oxidative deterioration. In juvenile rat subdermal implants, BP-POZ demonstrated reduced AGE formation and serum albumin infiltration, while calcification was not inhibited. However, BP-POZ rat subdermal implants with ethanol pretreatment demonstrated inhibition of both AGE accumulation and calcification. Ex vivo laminar flow studies with human blood demonstrated BP-POZ enhanced thromboresistance with reduced white blood cell accumulation. We conclude that SVD associated with AGE and serum protein accumulation can be mitigated through POZ functionalization that both enhances biocompatibility and facilitates ethanol pretreatment inhibition of BP calcification.
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Doenças das Valvas Cardíacas/tratamento farmacológico , Doenças das Valvas Cardíacas/terapia , Oxazóis/farmacologia , Pericárdio/efeitos dos fármacos , Animais , Materiais Biocompatíveis , Calcificação Fisiológica/efeitos dos fármacos , Calcinose/tratamento farmacológico , Calcinose/metabolismo , Calcinose/terapia , Linhagem Celular , Colágeno/metabolismo , Etanol/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Doenças das Valvas Cardíacas/metabolismo , Próteses Valvulares Cardíacas , Xenoenxertos/efeitos dos fármacos , Humanos , Masculino , Oxirredução/efeitos dos fármacos , Pericárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Células THP-1RESUMO
OBJECTIVE: We urgently need to understand Alzheimer's disease (AD) stigma among Black adults. Black communities bear a disproportionate burden of AD, and recent advances in early diagnosis using AD biomarkers may affect stigma associated with AD. The goal of our study is to characterize AD stigma within our cohort of self-identified Black participants and test how AD biomarker test results may affect this stigma. DESIGN: We surveyed a sample of 1,150 self-identified Black adults who were randomized to read a vignette describing a fictional person, who was described as either having a positive or negative biomarker test result. After reading the vignette, participants completed the modified Family Stigma in Alzheimer's Disease Scale (FS-ADS). We compared FS-ADS scores between groups defined by age, gender, and United States Census region. We examined interactions between these groupings and AD biomarker test result. RESULTS: Participants over age 65 had lower scores (lower stigma) on all 7 FS-ADS domains compared to those under 65: structural discrimination, negative severity attributions, negative aesthetic attributions, antipathy, support, pity, and social distance. In the biomarker positive condition, worries about structural discrimination were greater than in the biomarker negative condition and statistically similar in the two age groups (DOR, 0.39 [95%CI, 0.22-0.69]). This pattern of results was similar for negative symptom attributions (DOR, 0.51 [95%CI, 0.28-0.90]). CONCLUSION: While older adults reported less AD stigma than younger adults, AD biomarker testing caused similarly high concerns about structural discrimination and negative severity attributions. Thus, use of AD biomarker diagnosis may increase AD stigma and exacerbate healthcare disparities known to effect AD diagnosis in some Black adults. Advances in AD diagnosis may interact with social and structural factors to differentially affect groups of Black adults.
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INTRODUCTION: How do reactions to a brain scan result differ between Black and White adults? The answer may inform efforts to reduce disparities in Alzheimer's disease (AD) diagnosis and treatment. METHODS: Self-identified Black (n = 1055) and White (n = 1451) adults were randomized to a vignette of a fictional patient at a memory center who was told a brain scan result. Measures of stigma and diagnosis confidence were compared between-groups. RESULTS: Black participants reported more stigma than White participants on four of seven domains in reaction to the patient at a memory center visit. Black participants' confidence in an AD diagnosis informed by a brain scan and other assessments was 72.2 points (95% confidence interval [CI] 70.4 to 73.5), which was lower than the respective rating for White participants [78.1 points (95%CI 77.0 to 79.3)]. DISCUSSION: Equitable access to early AD diagnosis will require public outreach and education that address AD stigma associated with a memory center visit.
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Doença de Alzheimer , Encéfalo , Adulto , Humanos , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Estigma Social , Negro ou Afro-Americano , BrancosRESUMO
We propose a dynamic allocation procedure that increases power and efficiency when measuring an average treatment effect in sequential randomized trials exploiting some subjects' previous assessed responses. Subjects arrive sequentially and are either randomized or paired to a previously randomized subject and administered the alternate treatment. The pairing is made via a dynamic matching criterion that iteratively learns which specific covariates are important to the response. We develop estimators for the average treatment effect as well as an exact test. We illustrate our method's increase in efficiency and power over other allocation procedures in both simulated scenarios and a clinical trial dataset. An R package "SeqExpMatch" for use by practitioners is available on CRAN.
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A central goal in designing clinical trials is to find the test that maximizes power (or equivalently minimizes required sample size) for finding a false null hypothesis subject to the constraint of type I error. When there is more than one test, such as in clinical trials with multiple endpoints, the issues of optimal design and optimal procedures become more complex. In this paper, we address the question of how such optimal tests should be defined and how they can be found. We review different notions of power and how they relate to study goals, and also consider the requirements of type I error control and the nature of the procedures. This leads us to an explicit optimization problem with objective and constraints that describe its specific desiderata. We present a complete solution for deriving optimal procedures for two hypotheses, which have desired monotonicity properties, and are computationally simple. For some of the optimization formulations this yields optimal procedures that are identical to existing procedures, such as Hommel's procedure or the procedure of Bittman et al. (2009), while for other cases it yields completely novel and more powerful procedures than existing ones. We demonstrate the nature of our novel procedures and their improved power extensively in a simulation and on the APEX study (Cohen et al., 2016).
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Projetos de Pesquisa , Simulação por Computador , Tamanho da Amostra , Ensaios Clínicos como AssuntoRESUMO
We discuss three issues. In the first part, we discuss the criteria emphasized by Maurer, Bretz, and Xun, warning that it modifies the per comparison error rate that does not address the concerns raised by multiple testing. In the second part, we strengthen the optimality results developed in the paper, based on our recent results. In the third part, we highlight the potentially important role that the use of weights may have in practice and discuss the difficulties in assigning weights that convey the importance in the gain and loss functions, especially as it pertains to multiple endpoints.
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Projetos de Pesquisa , Interpretação Estatística de DadosRESUMO
In individuals with autism spectrum disorder (ASD), de novo mutations have previously been shown to be significantly correlated with lower IQ but not with the core characteristics of ASD: deficits in social communication and interaction and restricted interests and repetitive patterns of behavior. We extend these findings by demonstrating in the Simons Simplex Collection that damaging de novo mutations in ASD individuals are also significantly and convincingly correlated with measures of impaired motor skills. This correlation is not explained by a correlation between IQ and motor skills. We find that IQ and motor skills are distinctly associated with damaging mutations and, in particular, that motor skills are a more sensitive indicator of mutational severity than is IQ, as judged by mutational type and target gene. We use this finding to propose a combined classification of phenotypic severity: mild (little impairment of either), moderate (impairment mainly to motor skills), and severe (impairment of both IQ and motor skills).
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Transtorno do Espectro Autista/genética , Destreza Motora/fisiologia , Criança , Feminino , Genótipo , Humanos , Masculino , MutaçãoRESUMO
We develop a method of analysis [affected to discordant sibling pairs (A2DS)] that tests if shared variants contribute to a disorder. Using a standard measure of genetic relation, test individuals are compared with a cohort of discordant sibling pairs (CDS) to derive a comparative similarity score. We ask if a test individual is more similar to an unrelated affected than to the unrelated unaffected sibling from the CDS and then, sum over such individuals and pairs. Statistical significance is judged by randomly permuting the affected status in the CDS. In the analysis of published genotype data from the Simons Simplex Collection (SSC) and the Autism Genetic Resource Exchange (AGRE) cohorts of children with autism spectrum disorder (ASD), we find strong statistical significance that the affected are more similar to the affected than to the unaffected of the CDS (P value â¼ 0.00001). Fathers in multiplex families have marginally greater similarity (P value = 0.02) to unrelated affected individuals. These results do not depend on ethnic matching or gender.
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Transtorno Autístico/genética , Transtorno Autístico/fisiopatologia , Irmãos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Criança , Pré-Escolar , Estudos de Coortes , Simulação por Computador , Saúde da Família , Feminino , Genótipo , Humanos , Masculino , Modelos Estatísticos , Polimorfismo de Nucleotídeo Único , Fatores SexuaisRESUMO
See Kleen and Kirsch (doi:10.1093/awx178) for a scientific commentary on this article.Cognitive deficits are common among epilepsy patients. In these patients, interictal epileptiform discharges, also termed spikes, are seen routinely on electroencephalography and believed to be associated with transient cognitive impairments. In this study, we investigated the effect of spikes on memory encoding and retrieval, taking into account the spatial distribution of spikes in relation to the seizure onset zone as well as anatomical regions of the brain. Sixty-seven patients with medication refractory epilepsy undergoing continuous intracranial electroencephalography monitoring engaged in a delayed free recall task to test short-term memory. In this task, subjects were asked to memorize and recall lists of common nouns. We quantified the effect of each spike on the probability of successful recall using a generalized logistic mixed model. We found that in patients with left lateralized seizure onset zones, spikes outside the seizure onset zone impacted memory encoding, whereas those within the seizure onset zone did not. In addition, spikes in the left inferior temporal gyrus, middle temporal gyrus, superior temporal gyrus, and fusiform gyrus during memory encoding reduced odds of recall by as much as 15% per spike. Spikes also reduced the odds of word retrieval, an effect that was stronger with spikes outside of the seizure onset zone. These results suggest that seizure onset regions are dysfunctional at baseline, and support the idea that interictal spikes disrupt cognitive processes related to the underlying tissue.
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Cognição/fisiologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Convulsões/fisiopatologia , Lobo Temporal/fisiopatologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
We propose a dynamic allocation procedure that increases power and efficiency when measuring an average treatment effect in fixed sample randomized trials with sequential allocation. Subjects arrive iteratively and are either randomized or paired via a matching criterion to a previously randomized subject and administered the alternate treatment. We develop estimators for the average treatment effect that combine information from both the matched pairs and unmatched subjects as well as an exact test. Simulations illustrate the method's higher efficiency and power over several competing allocation procedures in both simulations and in data from a clinical trial.
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Biometria/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Algoritmos , Amitriptilina/uso terapêutico , Simulação por Computador , Cistite Intersticial/tratamento farmacológico , Humanos , Modelos Lineares , Modelos Estatísticos , Dinâmica não Linear , Resultado do TratamentoRESUMO
Recurrent copy number variations (CNVs) of human 16p11.2 have been associated with a variety of developmental/neurocognitive syndromes. In particular, deletion of 16p11.2 is found in patients with autism, developmental delay, and obesity. Patients with deletions or duplications have a wide range of clinical features, and siblings carrying the same deletion often have diverse symptoms. To study the consequence of 16p11.2 CNVs in a systematic manner, we used chromosome engineering to generate mice harboring deletion of the chromosomal region corresponding to 16p11.2, as well as mice harboring the reciprocal duplication. These 16p11.2 CNV models have dosage-dependent changes in gene expression, viability, brain architecture, and behavior. For each phenotype, the consequence of the deletion is more severe than that of the duplication. Of particular note is that half of the 16p11.2 deletion mice die postnatally; those that survive to adulthood are healthy and fertile, but have alterations in the hypothalamus and exhibit a "behavior trap" phenotype-a specific behavior characteristic of rodents with lateral hypothalamic and nigrostriatal lesions. These findings indicate that 16p11.2 CNVs cause brain and behavioral anomalies, providing insight into human neurodevelopmental disorders.
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Transtorno Autístico/genética , Cromossomos Humanos Par 16/genética , Dosagem de Genes , Animais , Comportamento Animal , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Deleção Cromossômica , Ritmo Circadiano/genética , Modelos Animais de Doenças , Feminino , Engenharia Genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fenótipo , Gravidez , TranscriptomaRESUMO
OBJECTIVES: Early diagnosis of Alzheimer's disease (AD) using brain scans and other biomarker tests will be essential to increasing the benefits of emerging disease-modifying therapies, but AD biomarkers may have unintended negative consequences on stigma. We examined how a brain scan result affects AD diagnosis confidence and AD stigma. METHODS: The study used a vignette-based experiment with a 2â ×â 2â ×â 3 factorial design of main effects: a brain scan result as positive or negative, treatment availability and symptom stage. We sampled 1,283 adults ages 65 and older between June 11and July 3, 2019. Participants (1) rated their confidence in an AD diagnosis in each of four medical evaluations that varied in number and type of diagnostic tools and (2) read a vignette about a fictional patient with varied characteristics before completing the Modified Family Stigma in Alzheimer's Disease Scale (FS-ADS). We examined mean diagnosis confidence by medical evaluation type. We conducted between-group comparisons of diagnosis confidence and FS-ADS scores in the positive versus negative brain scan result conditions and, in the positive condition, by symptom stage and treatment availability. RESULTS: A positive versus negative test result corresponds with higher confidence in an AD diagnosis independent of medical evaluation type (all pâ <â .001). A positive result correlates with stronger reactions on 6 of 7 FS-ADS domains (all pâ <â .001). DISCUSSION: A positive biomarker result heightens AD diagnosis confidence but also correlates with more AD stigma. Our findings inform strategies to promote early diagnosis and clinical discussions with individuals undergoing AD biomarker testing.
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Doença de Alzheimer , Estigma Social , Humanos , Doença de Alzheimer/psicologia , Doença de Alzheimer/diagnóstico por imagem , Masculino , Idoso , Feminino , Diagnóstico Precoce , Idoso de 80 Anos ou mais , Neuroimagem/métodos , Encéfalo/diagnóstico por imagem , Biomarcadores , AutoimagemRESUMO
OBJECTIVES: This study assessed the state of pediatric medical device (PMD) development by comparing PMD clinical trials to pediatric trials evaluating drugs and biologics, from 1999 to 2022. METHODS: The site www.clinicaltrials.gov was used to identify and quantify both PMD clinical trials and pediatric trials for drugs and biologics. Clinical specialty was also assessed. The institutions included were the 7 children's hospitals primarily affiliated with the Food and Drug Administration (FDA) Pediatric Device Consortia (PDC) grant program between 2018 and 2023. For a national comparison, an additional search assessed PMD trials across all US medical institutions. RESULTS: A total of 243 PMD clinical trials were identified at the FDA-PDC institutions on the basis of the year of initiation; the average number of PMD trials initiated per year per institution was 1.5 from 1999 to 2022. However, PMD trials significantly increased during the period 2014 to 2022 compared with 1999 to 2013 (P < .001); the rate of initiation of drug and biologic pediatric trials demonstrated no significant differences between these time periods. A national survey of all institutions initiating PMD trials, and drugs and biologics trials, identified 1885 PMD trials out of a total 12 943. A comparable trend was noted in the national survey with initiation of PMD trials increasing significantly from 2014 to 2022 (P < .001), compared with 1999 to 2013, whereas the rate of initiation of drug and biologic trials during these periods did not demonstrate a significant change. CONCLUSIONS: Although pediatric clinical trial initiation for drugs and biologics remained stable from 1999 to 2022, the rate of new PMD trials significantly increased during the period 2014 to 2022 at FDA-PDC institutions and nationally.
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Ensaios Clínicos como Assunto , Humanos , Estados Unidos , Criança , Equipamentos e Provisões , United States Food and Drug Administration , Pediatria , Produtos Biológicos/uso terapêutico , Hospitais Pediátricos , Aprovação de EquipamentosRESUMO
High-frequency (100-500 Hz) oscillations (HFOs) recorded from intracranial electrodes are a potential biomarker for epileptogenic brain. HFOs are commonly categorized as ripples (100-250 Hz) or fast ripples (250-500 Hz), and a third class of mixed frequency events has also been identified. We hypothesize that temporal changes in HFOs may identify periods of increased the likelihood of seizure onset. HFOs (86,151) from five patients with neocortical epilepsy implanted with hybrid (micro + macro) intracranial electrodes were detected using a previously validated automated algorithm run over all channels of each patient's entire recording. HFOs were characterized by extracting quantitative morphologic features and divided into four time epochs (interictal, preictal, ictal, and postictal) and three HFO clusters (ripples, fast ripples, and mixed events). We used supervised classification and nonparametric statistical tests to explore quantitative changes in HFO features before, during, and after seizures. We also analyzed temporal changes in the rates and proportions of events from each HFO cluster during these periods. We observed patient-specific changes in HFO morphology linked to fluctuation in the relative rates of ripples, fast ripples, and mixed frequency events. These changes in relative rate occurred in pre- and postictal periods up to thirty min before and after seizures. We also found evidence that the distribution of HFOs during these different time periods varied greatly between individual patients. These results suggest that temporal analysis of HFO features has potential for designing custom seizure prediction algorithms and for exploring the relationship between HFOs and seizure generation.
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Ondas Encefálicas/fisiologia , Epilepsia/fisiopatologia , Neocórtex/fisiopatologia , Adulto , Biomarcadores , Interpretação Estatística de Dados , Eletroencefalografia , Epilepsia/classificação , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto JovemRESUMO
The development and maintenance of mitochondrial heteroplasmy has important consequences for both health and heredity. Previous studies using pathogenic mutations have shown considerable variability between maternally related individuals and studies of several D-loop polymorphisms have suggested a relationship between heteroplasmy and somatic aging. To broadly explore the variation of human heteroplasmy and to clarify the dynamics of somatic heteroplasmy over the course of lifespan, we analyzed mitochondrial sequence variation across a range of ages. We utilized array-generated single-nucleotide polymorphism data that were well correlated with independent measures of heteroplasmy. Significant levels of heteroplasmy were identified at 0.24% of sites evaluated. By examining mother-child pairs, we found that heteroplasmy was inherited (30%) but could occur de novo in offspring or, conversely, be present in mothers but eliminated in their children (70%). Cumulatively, mitochondrial heteroplasmy across the genome increased significantly with advanced age (r = 0.224, P =8 × 10(-30)). Surprisingly, changes in heteroplasmy were not uniform with some sites demonstrating a loss of variation (increased homoplasmy) with aging. These data suggest that both mutation and selective pressure affect blood mitochondrial DNA sequence over the course of the human lifespan and reveal the unexpectedly dynamic nature of human heteroplasmy.
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Envelhecimento/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Mitocôndrias/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Feminino , Genótipo , Hereditariedade , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Adulto JovemRESUMO
Studying thousands of families, we find siblings concordant for autism share more of their parental genomes than expected by chance, and discordant siblings share less, consistent with a role of transmission in autism incidence. The excess sharing of the father is highly significant (p value of 0.0014), with less significance for the mother (p value of 0.31). To compare parental sharing, we adjust for differences in meiotic recombination to obtain a p value of 0.15 that they are shared equally. These observations are contrary to certain models in which the mother carries a greater load than the father. Nevertheless, we present models in which greater sharing of the father is observed even though the mother carries a greater load. More generally, our observations of sharing establish quantitative constraints that any complete genetic model of autism must satisfy, and our methods may be applicable to other complex disorders.
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Degenerative mitral valve (MV) regurgitation (MR) is a highly prevalent heart disease that requires surgery in severe cases. Here, we show that a decrease in the activity of the serotonin transporter (SERT) accelerates MV remodeling and progression to MR. Through studies of a population of patients with MR, we show that selective serotonin reuptake inhibitor (SSRI) use and SERT promoter polymorphism 5-HTTLPR LL genotype were associated with MV surgery at younger age. Functional characterization of 122 human MV samples, in conjunction with in vivo studies in SERT-/- mice and wild-type mice treated with the SSRI fluoxetine, showed that diminished SERT activity in MV interstitial cells (MVICs) contributed to the pathophysiology of MR through enhanced serotonin receptor (HTR) signaling. SERT activity was decreased in LL MVICs partially because of diminished membrane localization of SERT. In mice, fluoxetine treatment or SERT knockdown resulted in thickened MV leaflets. Similarly, silencing of SERT in normal human MVICs led to up-regulation of transforming growth factor ß1 (TGFß1) and collagen (COL1A1) in the presence of serotonin. In addition, treatment of MVICs with fluoxetine not only directly inhibited SERT activity but also decreased SERT expression and increased HTR2B expression. Fluoxetine treatment and LL genotype were also associated with increased COL1A1 expression in the presence of serotonin in MVICs, and these effects were attenuated by HTR2B inhibition. These results suggest that assessment of both 5-HTTLPR genotype and SERT-inhibiting treatments may be useful tools to risk-stratify patients with MV disease to estimate the likelihood of rapid disease progression.
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Insuficiência da Valva Mitral , Valva Mitral , Humanos , Animais , Camundongos , Valva Mitral/metabolismo , Insuficiência da Valva Mitral/metabolismo , Fluoxetina/farmacologia , Fluoxetina/uso terapêutico , Fluoxetina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Serotonina/metabolismo , Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêuticoRESUMO
Transient high-frequency (100-500 Hz) oscillations of the local field potential have been studied extensively in human mesial temporal lobe. Previous studies report that both ripple (100-250 Hz) and fast ripple (250-500 Hz) oscillations are increased in the seizure-onset zone of patients with mesial temporal lobe epilepsy. Comparatively little is known, however, about their spatial distribution with respect to seizure-onset zone in neocortical epilepsy, or their prevalence in normal brain. We present a quantitative analysis of high-frequency oscillations and their rates of occurrence in a group of nine patients with neocortical epilepsy and two control patients with no history of seizures. Oscillations were automatically detected and classified using an unsupervised approach in a data set of unprecedented volume in epilepsy research, over 12 terabytes of continuous long-term micro- and macro-electrode intracranial recordings, without human preprocessing, enabling selection-bias-free estimates of oscillation rates. There are three main results: (i) a cluster of ripple frequency oscillations with median spectral centroid = 137 Hz is increased in the seizure-onset zone more frequently than a cluster of fast ripple frequency oscillations (median spectral centroid = 305 Hz); (ii) we found no difference in the rates of high frequency oscillations in control neocortex and the non-seizure-onset zone neocortex of patients with epilepsy, despite the possibility of different underlying mechanisms of generation; and (iii) while previous studies have demonstrated that oscillations recorded by parenchyma-penetrating micro-electrodes have higher peak 100-500 Hz frequencies than penetrating macro-electrodes, this was not found for the epipial electrodes used here to record from the neocortical surface. We conclude that the relative rate of ripple frequency oscillations is a potential biomarker for epileptic neocortex, but that larger prospective studies correlating high-frequency oscillations rates with seizure-onset zone, resected tissue and surgical outcome are required to determine the true predictive value.
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Ondas Encefálicas/fisiologia , Epilepsia/fisiopatologia , Neocórtex/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Eletrodos Implantados , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
OBJECTIVE: The symptoms and prognosis of Alzheimer's disease (AD) dementia contribute to the public's negative reactions toward individuals with AD dementia and their families. But what if, using AD biomarker tests, diagnosis was made before the onset of dementia, and a disease-modifying treatment was available? This study tests the hypotheses that a "preclinical" diagnosis of AD and treatment that improves prognosis will mitigate stigmatizing reactions. METHODS: A sample of U.S. adults were randomized to receive one vignette created by a 3 × 2 × 2 vignette-based experiment that described a person with varied clinical symptom severity (Clinical Dementia Rating stages 0 (no dementia), 1 (mild), or 2 (moderate)), AD biomarker test results (positive vs negative), and disease-modifying treatment (available vs not available). Between-group comparisons were conducted of scores on the Modified Family Stigma in Alzheimer's Disease Scale (FS-ADS). RESULTS: The sample of 1,817 adults had a mean age two years younger than that of U.S. adults but was otherwise similar to the general adult population. The response rate was 63% and the completion rate was 96%. In comparisons of randomized groups, mild and moderate symptoms of dementia evoked stronger reactions on all FS-ADS domains compared to no dementia (all p < 0.001). A positive biomarker test result evoked stronger reactions on all but one FS-ADS domain (negative aesthetic attributions) compared to a negative biomarker result (all p < 0.001). Disease-modifying treatment had no measurable influence on stigma (all p > 0.05). CONCLUSIONS: The stigmas of dementia spill over into preclinical AD, and availability of treatment does not alter that stigma. Translation of the preclinical AD construct from research into practice will require interventions that mitigate AD stigma to preserve the dignity and identity of individuals living with AD.
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Doença de Alzheimer , Adulto , Biomarcadores , Pré-Escolar , Humanos , Prognóstico , Percepção Social , Estigma SocialRESUMO
Bioprosthetic heart valves (BHV) fabricated from heterograft tissue, such as glutaraldehyde pretreated bovine pericardium (BP), are the most frequently used heart valve replacements. BHV durability is limited by structural valve degeneration (SVD), mechanistically associated with calcification, advanced glycation end products (AGE), and serum protein infiltration. We investigated the hypothesis that anti-AGE agents, Aminoguanidine, Pyridoxamine [PYR], and N-Acetylcysteine could mitigate AGE-serum protein SVD mechanisms in vitro and in vivo, and that these agents could mitigate calcification or demonstrate anti-calcification interactions with BP pretreatment with ethanol. In vitro, each of these agents significantly inhibited AGE-serum protein infiltration in BP. However, in 28-day rat subdermal BP implants only orally administered PYR demonstrated significant inhibition of AGE and serum protein uptake. Furthermore, BP PYR preincubation of BP mitigated AGE-serum protein SVD mechanisms in vitro, and demonstrated mitigation of both AGE-serum protein uptake and reduced calcification in vivo in 28-day rat subdermal BP explants. Inhibition of BP calcification as well as inhibition of AGE-serum protein infiltration was observed in 28-day rat subdermal BP explants pretreated with ethanol followed by PYR preincubation. In conclusion, AGE-serum protein and calcification SVD pathophysiology are significantly mitigated by both PYR oral therapy and PYR and ethanol pretreatment of BP.