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1.
bioRxiv ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39131292

RESUMEN

Recent work has leveraged massive datasets and advanced harmonization methods to construct normative models of neuroanatomical features and benchmark individuals' morphology. However, current harmonization tools do not preserve the effects of biological covariates including sex and age on features' variances; this failure may induce error in normative scores, particularly when such factors are distributed unequally across sites. Here, we introduce a new extension of the popular ComBat harmonization method, ComBatLS, that preserves biological variance in features' locations and scales. We use UK Biobank data to show that ComBatLS robustly replicates individuals' normative scores better than other ComBat methods when subjects are assigned to sex-imbalanced synthetic "sites". Additionally, we demonstrate that ComBatLS significantly reduces sex biases in normative scores compared to traditional methods. Finally, we show that ComBatLS successfully harmonizes consortium data collected across over 50 studies. R implementation of ComBatLS is available at https://github.com/andy1764/ComBatFamily.

2.
J Gastrointest Surg ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39127405

RESUMEN

BACKGROUND: Pyloroplasty is an effective surgery for gastroparesis. However, some patients fail to improve after pyloric drainage and may require subsequent gastric electric stimulation. There is a paucity of data on the efficacy of gastric stimulator as an adjunct to failed pyloroplasty. This study aimed to describe our experience with pyloroplasty, determine the efficacy of gastric stimulator for failed pyloroplasty, and compare the final outcomes of those who required pyloroplasty with and without gastric stimulator for gastroparesis. METHODS: Records of patients who underwent primary pyloroplasty for gastroparesis at our institution were reviewed. Patients with poor symptomatic improvement after pyloroplasty underwent subsequent gastric stimulator. Symptoms were assessed using the gastroparesis cardinal symptom index (GCSI) preoperatively and after each surgery. Severe gastroparesis was defined as GCSI total score ≥3. Outcomes were assessed after pyloroplasty in all patients and after stimulator in patients who failed pyloroplasty. Final outcomes were then compared between those who did and did not require adjunct gastric stimulator. RESULTS: The study population consisted of 104 patients (89.4% females) with a mean (SD) age of 42.2 years (11) and body mass index of 26.9 kg/m2 (7). Gastroparesis etiologies were 71.2% idiopathic, 17.3% diabetic, and 11.5% postsurgical. At 18.7 months (12) after pyloroplasty, there was a decrease in the GCSI total score (3.5 [1] to 2.7 [1.2]; P = .0012) and the rate of severe gastroparesis (71.9%-29.3%; P < .0001). Gastric emptying scintigraphy (GES) 4-hour retention decreased (36.5 [24] to 15.3 [18]; P = .0003). Adjunct gastric stimulator was required by 30 patients (28.8%) owing to suboptimal outcomes with no improvement in GCSI (P = .201) or GES (P = .320). These patients were younger (40.5 [10.6] vs 49.6 [15.2] years; P = .0016), with higher baseline GCSI total scores (4.3 [0.7] vs 3.7 [1.1]; P < .001) and more severe gastroparesis (100% vs 55.6%; P < .001). All other preoperative characteristics were similar. At 21.7 months (15) after gastric stimulator, there was improvement in GCSI (4.1 [0.7] to 2.6 [1.1]; P < .0001), severe gastroparesis (100%-33.3%; P < .0001), and GES 4-hour retention (21.2 [22] to 7.6 [10]; P = .054). Before gastric stimulator, those who failed pyloroplasty had significantly worse GCSI (P = .0009) and GES (P = .048). However, after gastric stimulator, GCSI and GES improved and were comparable with those who only required pyloroplasty (P > .05). CONCLUSION: Pyloroplasty improved gastroparesis symptoms and gastric emptying, yet 28% failed, requiring gastric stimulator. Younger patients and those with preoperative GCSI scores ≥3 were more likely to fail. Gastric stimulator improved outcomes after failed pyloroplasty, with comparable final GCSI and GES with those who did not fail.

3.
J Voice ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38641520

RESUMEN

INTRODUCTION: Magnetic sphincter augmentation (MSA) is an effective treatment for typical reflux symptoms, but data on its impact on laryngopharyngeal reflux (LPR) is limited. This study aimed to determine the efficacy of MSA for LPR and to identify predictors of outcome. METHODS: This was a retrospective review of 775 patients who underwent MSA between 2013 and 2021. LPR was defined as presence of atypical reflux symptoms and a reflux symptom index (RSI) score >13. Favorable outcome was defined as primary symptom resolution, freedom from proton pump inhibitors, and five-point improvement or RSI score normalization. Preoperative clinical, high-resolution manometry, and impedance-pH data were analyzed for impact on favorable outcome using univariate followed by multivariable analysis. RESULTS: There were 128 patients who underwent MSA for LPR. At a mean (SD) follow-up of 13 (5.4) months, favorable outcome was achieved by 80.4% of patients, with median (IQR) RSI score improving from 29 (22-35) to 9 (4-17), (P < 0.001). Independent predictors of favorable outcome on multivariable analysis included LPR with typical reflux symptoms [OR (95% CI): 8.9 (2.3-31.1), P = 0.001], >80% intact swallow on high-resolution manometry [OR (95% CI): 3.8 (1.0-13.3), P = 0.035], upper esophageal sphincter (UES) resting pressure >34 mmHg [OR (95% CI): 4.1 (1.1-14.1), P = 0.027] and short total proximal acid clearance time [OR (95% CI): 1.1 (1.0-1.1), P = 0.031]. Impedance parameters including number of LPR events, full column reflux and proximal acid exposure events were similar between outcome groups (P > 0.05). CONCLUSION: MSA is an effective surgery for patients with LPR. Patients with concomitant typical reflux symptoms, normal esophageal body motility, and competent UES benefit the most from surgery. Individual impedance-pH parameters were not associated with outcome.

4.
Radiology ; 309(1): e230096, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37906015

RESUMEN

Background Clinically acquired brain MRI scans represent a valuable but underused resource for investigating neurodevelopment due to their technical heterogeneity and lack of appropriate controls. These barriers have curtailed retrospective studies of clinical brain MRI scans compared with more costly prospectively acquired research-quality brain MRI scans. Purpose To provide a benchmark for neuroanatomic variability in clinically acquired brain MRI scans with limited imaging pathology (SLIPs) and to evaluate if growth charts from curated clinical MRI scans differed from research-quality MRI scans or were influenced by clinical indication for the scan. Materials and Methods In this secondary analysis of preexisting data, clinical brain MRI SLIPs from an urban pediatric health care system (individuals aged ≤22 years) were scanned across nine 3.0-T MRI scanners. The curation process included manual review of signed radiology reports and automated and manual quality review of images without gross pathology. Global and regional volumetric imaging phenotypes were measured using two image segmentation pipelines, and clinical brain growth charts were quantitatively compared with charts derived from a large set of research controls in the same age range by means of Pearson correlation and age at peak volume. Results The curated clinical data set included 532 patients (277 male; median age, 10 years [IQR, 5-14 years]; age range, 28 days after birth to 22 years) scanned between 2005 and 2020. Clinical brain growth charts were highly correlated with growth charts derived from research data sets (22 studies, 8346 individuals [4947 male]; age range, 152 days after birth to 22 years) in terms of normative developmental trajectories predicted by the models (median r = 0.979). Conclusion The clinical indication of the scans did not significantly bias the output of clinical brain charts. Brain growth charts derived from clinical controls with limited imaging pathology were highly correlated with brain charts from research controls, suggesting the potential of curated clinical MRI scans to supplement research data sets. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Ertl-Wagner and Pai in this issue.


Asunto(s)
Encéfalo , Gráficos de Crecimiento , Humanos , Masculino , Niño , Recién Nacido , Estudios Retrospectivos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Cabeza
5.
J Gastrointest Surg ; 27(11): 2684-2693, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37848686

RESUMEN

INTRODUCTION: Esophagogastric junction outflow obstruction (EGJOO) is an esophageal motility disorder characterized by failure of lower esophageal sphincter (LES) relaxation with preserved peristalsis. Studies have shown that Heller myotomy with Dor fundoplication (HMD) and per oral endoscopic myotomy (POEM) are effective treatments for EGJOO. However, there is paucity of data comparing the efficacy and impact of these two procedures. Therefore, the aim of this study was to compare outcomes and impact on esophageal physiology in patients undergoing HMD or POEM for primary EGJOO. METHODS: This was a retrospective review of patients who underwent either HMD or POEM for primary EGJOO at our institution between 2013 and 2021. Favorable outcome was defined as an Eckardt score ≤ 3 at 1 year after surgery. GERD-HRQL questionnaire, endoscopy, pH monitoring, and high-resolution manometry (HRM) results at baseline and 1 year after surgery were compared pre- and post-surgery and between groups. Objective GERD was defined as DeMeester score > 14.7 or LA grade C/D esophagitis. RESULTS: The final study population consisted of 52 patients who underwent HMD (n = 35) or POEM (n = 17) for EGJOO. At a mean (SD) follow-up of 24.6 (15.3) months, favorable outcome was achieved by 30 (85.7%) patients after HMD and 14 (82.4%) after POEM (p = 0.753). After HMD, there was a decrease GERD-HRQL total score (31 (22-45) to 4 (0-19); p < 0.001), and objective reflux (54.2 to 25.9%; p = 0.033). On manometry, there was a decrease in LES resting pressure (48 (34-59) to 13 (8-17); p < 0.001) and IRP (22 (17-28) to 8 (3-11); p < 0.001), but esophageal body characteristics did not change (p > 0.05). Incomplete bolus clearance improved (70% (10-90) to 10% (0-40); p = 0.010). After POEM, there was no change in the GERD-HRQL total score (p = 0.854), but objective reflux significantly increased (0 to 62%; p < 0.001). On manometry, there was a decrease in LES resting pressure (43 (30-68) to 31 (5-34); p = 0.042) and IRP (23 (18-33) to 12 (10-32); p = 0.048), DCI (1920 (1600-5500) to 0 (0-814); p = 0.035), with increased failed swallows (0% (0-30) to 100% (10-100); p = 0.032). Bolus clearance did not improve (p = 0.539). Compared to HMD, POEM had a longer esophageal myotomy length (11 (7-15)-vs-5 (5-6); p = 0.001), more objective reflux (p = 0.041), lower DCI (0 (0-814)-vs-1695 (929-3101); p = 0.004), and intact swallows (90 (70-100)-vs-0 (0-40); p = 0.006), but more failed swallows (100 (10-100); p = 0.018) and incomplete bolus clearance (90 (90-100)-vs-10 (0-40); p = 0.004). CONCLUSION: Peroral endoscopic myotomy and Heller myotomy with Dor fundoplication are equally effective at relieving EGJOO symptoms. However, POEM causes worse reflux and near complete loss of esophageal body function.


Asunto(s)
Acalasia del Esófago , Trastornos de la Motilidad Esofágica , Reflujo Gastroesofágico , Miotomía de Heller , Cirugía Endoscópica por Orificios Naturales , Gastropatías , Humanos , Acalasia del Esófago/diagnóstico , Fundoplicación/métodos , Trastornos de la Motilidad Esofágica/etiología , Trastornos de la Motilidad Esofágica/cirugía , Esfínter Esofágico Inferior/cirugía , Reflujo Gastroesofágico/etiología , Manometría , Resultado del Tratamiento , Gastropatías/etiología , Cirugía Endoscópica por Orificios Naturales/efectos adversos , Cirugía Endoscópica por Orificios Naturales/métodos , Unión Esofagogástrica/cirugía
6.
Schizophr Res ; 250: 100-103, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36399898

RESUMEN

The Schizophrenia Exome Meta-Analysis (SCHEMA) consortium identified 10 genes in which loss-of-function (LoF) variants are highly associated with schizophrenia (SZ). In a well-characterized sample of 988 patients with psychotic disorders, we investigated whether patients bearing a SCHEMA variant presented with unusual or unique signs, symptoms, or course of illness. We identified 5 patients who carried a LoF variant in a SCHEMA gene, each in a different gene. None of the patients with a SCHEMA variant had unique symptoms. However, compared to the average of patients in the sample, all of the patients with a SCHEMA variant had earlier onset of any mental illness and more hospitalizations. Also, among SCHEMA carriers, 80 % were treated with clozapine, 60 % with ECT, all with either clozapine or ECT and 40 % with both clozapine and ECT, compared to only 2 % treated with clozapine and 18 % treated with ECT in the comparison group of patients without SCHEMA variants. All 5 patients with a SCHEMA variant had polysubstance abuse, and all had attempted suicide. Fewer than half had such presentations in the group without SCHEMA variants. In this small sample, SCHEMA variants appear to be associated with earlier onset, less favorable response to standard first-line treatments, and more severe illness, but not unique presentations of illness.


Asunto(s)
Antipsicóticos , Clozapina , Terapia Electroconvulsiva , Trastornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/complicaciones , Esquizofrenia/genética , Esquizofrenia/diagnóstico , Resultado del Tratamiento , Trastornos Psicóticos/tratamiento farmacológico , Clozapina/uso terapéutico , Antipsicóticos/uso terapéutico
7.
Artículo en Inglés | MEDLINE | ID: mdl-36118842

RESUMEN

Semantic differential techniques are a useful, well-validated tool to assess affective processing of stimuli and determine how that processing is impacted by various demographic factors, such as gender. In this paper, we explore differences in connotative word processing between men and women as measured by Osgood's semantic differential and what those differences imply about affective processing in the two genders. We recruited 94 young participants (47 men, 47 women, ages 18-39) using an online survey and collected their affective ratings of 120 words on three rating tasks: Evaluation (E), Potency (P), and Activity (A). With these data, we explored the theoretical and mathematical overlap between Osgood's affective meaning factor structure and other models of emotional processing commonly used in gender analyses. We then used Osgood's three-dimensional structure to assess gender-related differences in three affective classes of words (words with connotation that is Positive, Neutral, or Negative for each task) and found that there was no significant difference between the genders when rating Positive words and Neutral words on each of the three rating tasks. However, young women consistently rated Negative words more negatively than young men did on all three of the independent dimensions. This confirms the importance of taking gender effects into account when measuring emotional processing. Our results further indicate there may be differences between Osgood's structure and other models of affective processing that should be further explored.

8.
Schizophr Bull ; 48(3): 712-720, 2022 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-34999898

RESUMEN

Microstructural abnormalities in the white matter (WM) are implicated in the pathophysiology of psychosis. In vivo magnetic resonance spectroscopy (MRS) can probe the brain's intracellular microenvironment through the measurement of transverse relaxation and diffusion of neurometabolites and possibly provide cell-specific information. In our previous studies, we observed differential metabolite signal abnormalities in first episode and chronic stages of psychosis. In the present work, longitudinal data were presented for the first time on white matter cell-type specific abnormalities using a combination of diffusion tensor spectroscopy (DTS), T2 MRS, and diffusion tensor imaging (DTI) from a group of 25 first episode psychosis patients and nine matched controls scanned at baseline and one and two years of follow-up. We observed significantly reduced choline ADC in the year 1 of follow-up (0.194 µm2/ms) compared to baseline (0.229 µm2/ms), followed by a significant increase in NAA ADC in the year 2 follow-up (0.258 µm2/ms) from baseline (0.222 µm2/ms) and year 1 follow-up (0.217 µm2/ms). In contrast, NAA T2 relaxation, reflecting a related but different aspect of microenvironment from diffusion, was reduced at year 1 follow-up (257 ms) compared to baseline (278 ms). These abnormalities were observed in the absence of any abnormalities in water relaxation and diffusion at any timepoint. These findings indicate that abnormalities are seen in in glial-enriched (choline) signals in early stages of psychosis, followed by the subsequent emergence of neuronal-enriched (NAA) diffusion abnormalities, all in the absence of nonspecific water signal abnormalities.


Asunto(s)
Trastornos Psicóticos , Sustancia Blanca , Ácido Aspártico , Encéfalo/metabolismo , Colina/metabolismo , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora/métodos , Humanos , Estudios Longitudinales , Trastornos Psicóticos/patología , Agua/metabolismo , Sustancia Blanca/patología
9.
Schizophr Bull Open ; 2(1): sgaa073, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33554120

RESUMEN

BACKGROUND: Converging evidence indicates impaired brain energy metabolism in schizophrenia and other psychotic disorders. Creatine kinase (CK) is pivotal in providing adenosine triphosphate in the cell and maintaining its levels when energy demand is increased. However, the activity of CK has not been investigated in patients with first-episode schizophrenia spectrum disorders. METHODS: Using in vivo phosphorus magnetization transfer spectroscopy, we measured CK first-order forward rate constant (k f ) in the frontal lobe, in patients with first-episode psychosis (FEP; n = 16) and healthy controls (n = 34), at rest. RESULTS: CK k f was significantly reduced in FEP compared to healthy controls. There were no differences in other energy metabolism-related measures, including phosphocreatine (PCr) or ATP, between groups. We also found increase in glycerol-3-phosphorylcholine, a putative membrane breakdown product, in patients. CONCLUSIONS: The results of this study indicate that brain bioenergetic abnormalities are already present early in the course of schizophrenia spectrum disorders. Future research is needed to identify the relationship of reduced CK k f with psychotic symptoms and to test treatment alternatives targeting this pathway. Increased glycerol-3-phosphorylcholine is consistent with earlier studies in medication-naïve patients and later studies in first-episode schizophrenia, and suggest enhanced synaptic pruning.

10.
Bioanalysis ; 12(22): 1597-1605, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33156693

RESUMEN

Over the developmental lifetime of a therapeutic protein, the immunogenicity assay validation history can become substantial, frustrating review of clinical immunogenicity within the biologics license application. In our experience, this can lead to questions by regulators, resulting in numerous information requests during the review process. To address this, we propose a new document, the method history report (MHR), which can comprehensively present the history of the immunogenicity assay for regulators, including assay development and validation. The flexibility of the MHR allows for adaptation to the specific needs of each therapeutic program, while maintaining a consistent template. Here, we detail the rationale, general outline and template for the MHR and recommend others consider adopting it for their biologics license application-related activities.


Asunto(s)
Bioensayo/métodos , Humanos , Estudios de Validación como Asunto
11.
Harv Rev Psychiatry ; 28(4): 255-270, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32692089

RESUMEN

BACKGROUND: The prevalence of severe mental illness (SMI) in correctional settings is alarmingly high. Some correctional facilities have developed mental health units (MHUs) to treat incarcerated individuals with SMI. OBJECTIVE: To identify existing MHUs in the United States and collate information on these units. DATA SOURCES: A systematic review using Criminal Justice Abstracts, ERIC, PsycINFO, PubMed, and SocINDEX, plus an exploratory review using the Google search engine were conducted. MHUs were included if they were located within an adult correctional facility in the United States, specifically catered to SMI populations, and were in active operation as of June 2019. RESULTS: Eleven articles were identified through the peer-reviewed literature, but there were still major gaps in the information on MHUs. The Google search identified 317 MHUs. The majority of units were located within prisons (79.5%) and served only men (76%). The Google search found information indicating that 169 (53.3%) offered groups or programming to inmates; 104 (32.8%) offered individual therapy; and 89 (23%) offered both. One hundred sixty-six units (52.4%) had dedicated mental health staff, and 75 (23.7%) provided mental health training to correctional officers. Information on funding and outcomes of the MHUs is presented. LIMITATIONS: Use of the Google search engine and sources that have not been peer reviewed limits the robustness of conclusions about the MHUs. CONCLUSIONS: Standards for developing and implementing MHUs are not widespread. The shortcomings of current MHUs are discussed in the context of desired criteria for size, staffing, and programming.


Asunto(s)
Instalaciones Correccionales , Servicios de Salud Mental/organización & administración , Servicios de Salud Mental/normas , Prisioneros , Humanos , Trastornos Mentales/diagnóstico , Trastornos Mentales/terapia , Salud Mental/educación , Estados Unidos
12.
Schizophr Res ; 208: 196-201, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30842029

RESUMEN

BACKGROUND: Visual hallucinations (VH) are a common, but understudied symptom of psychosis, experienced by individuals across diagnostic categories of psychotic and neuropsychiatric conditions. There are limited data on VH and associated clinical phenotypes in adult idiopathic psychotic disorders, which are needed to elucidate their relevance to psychotic illness paradigms. METHOD: In this cross-sectional study, we examined clinical risk factors for VH in a well-characterized sample of 766 patients with adult psychotic disorders across diagnostic categories of schizophrenia (n = 227), schizoaffective disorder (n = 210), and bipolar I disorder (n = 329). The Structured Clinical Interview for DSM-IV-TR was used for diagnosis and symptom measurements. RESULTS: The prevalence of VH was 26.1% (200/766). Multivariate logistic regression showed that VH were independently associated with the presence of hallucinations in other modalities, including auditory, tactile, olfactory, and gustatory hallucinations. History of a suicide attempt and catatonic behavior were also associated with VH. In addition, specific delusions were associated with VH, in particular, delusions of control, and religious, erotomanic and jealousy delusions. Diagnosis, negative symptoms, and family history of psychosis were not independent predictors of VH. CONCLUSIONS: Results showed the clinical and disease relevance of VH as they were associated with severe morbidity of illness, including suicide attempts and catatonic behavior. Findings also suggest a phenotype associated with hallucinations in other modalities and specific types of delusions. Based on our findings, VH may be a significant factor in assessing for suicidality and illness severity, warranting clinical attention and further study of underlying mechanisms.


Asunto(s)
Trastorno Bipolar/epidemiología , Alucinaciones/epidemiología , Trastornos Psicóticos/epidemiología , Esquizofrenia/epidemiología , Intento de Suicidio , Adulto , Catatonia/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Prevalencia , Percepción Visual
13.
Alzheimers Dement (Amst) ; 10: 604-614, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30417070

RESUMEN

INTRODUCTION: Developing biomarkers that distinguish individuals with Alzheimer's disease (AD) from those with normal cognition remains a crucial goal for improving the health of older adults. We investigated adding brain spatial information to temporal event-related potentials (ERPs) to increase AD identification accuracy over temporal ERPs alone. METHODS: With two-step principal components analysis, we applied multivariate analyses that incorporated temporal and spatial ERP information from a cognitive task. Discriminant analysis used temporospatial ERP scores to classify participants as belonging to either the AD or healthy control group. RESULTS: Temporospatial ERPs produced a cross-validated area under the curve of 0.84. Adding spatial information through a formal procedure significantly improves classification accuracy. DISCUSSION: A weighted combination of temporospatial ERP markers performs well in detecting AD. Because ERPs are noninvasive and inexpensive, they may be promising biomarkers for AD that can add functional information to other biomarker systems while providing the individual's probability of correct classification.

14.
Clin Neurophysiol ; 127(6): 2423-35, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27178862

RESUMEN

OBJECTIVE: To determine how aging and dementia affect the brain's initial storing of task-relevant and irrelevant information in short-term memory. METHODS: We used brain Event-Related Potentials (ERPs) to measure short-term memory storage (ERP component C250) in 36 Young Adults, 36 Normal Elderly, and 36 early-stage AD subjects. Participants performed the Number-Letter task, a cognitive paradigm requiring memory storage of a first relevant stimulus to compare it with a second stimulus. RESULTS: In Young Adults, C250 was more positive for the first task-relevant stimulus compared to all other stimuli. C250 in Normal Elderly and AD subjects was roughly the same to relevant and irrelevant stimuli in Intratrial Parts 1-3 but not 4. The AD group had lower C250 to relevant stimuli in part 1. CONCLUSIONS: Both normal aging and dementia cause less differentiation of relevant from irrelevant information in initial storage. There was a large aging effect involving differences in the pattern of C250 responses of the Young Adult versus the Normal Elderly/AD groups. Also, a potential dementia effect was obtained. SIGNIFICANCE: C250 is a candidate tool for measuring short-term memory performance on a biological level, as well as a potential marker for memory changes due to normal aging and dementia.


Asunto(s)
Envejecimiento/fisiología , Enfermedad de Alzheimer/fisiopatología , Potenciales Evocados , Memoria a Corto Plazo , Adulto , Anciano , Femenino , Humanos , Masculino
15.
Brain Res ; 1604: 74-83, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25641043

RESUMEN

Brain event-related potentials (ERPs) offer a quantitative link between neurophysiological activity and cognitive performance. ERPs were measured while young adults performed a task that required storing a relevant stimulus in short-term memory. Using principal components analysis, ERP component C250 (maximum at 250 ms post-stimulus) was extracted from a set of ERPs that were separately averaged for various task conditions, including stimulus relevancy and stimulus sequence within a trial. C250 was more positive in response to task-specific stimuli that were successfully stored in short-term memory. This relationship between C250 and short-term memory storage of a stimulus was confirmed by a memory probe recall test where the behavioral recall of a stimulus was highly correlated with its C250 amplitude. ERP component P300 (and its subcomponents of P3a and P3b, which are commonly thought to represent memory operations) did not show a pattern of activation reflective of storing task-relevant stimuli. C250 precedes the P300, indicating that initial short-term memory storage may occur earlier than previously believed. Additionally, because C250 is so strongly predictive of a stimulus being stored in short-term memory, C250 may provide a strong index of early memory operations.


Asunto(s)
Encéfalo/fisiología , Potenciales Evocados/fisiología , Memoria a Corto Plazo/fisiología , Adulto , Biomarcadores/análisis , Estudios de Casos y Controles , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Femenino , Humanos , Masculino , Análisis de Componente Principal , Adulto Joven
16.
J Pathol ; 236(1): 41-52, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25500911

RESUMEN

Inherited syndromes provide unique opportunities to identify key regulatory mechanisms governing human disease. We previously identified germline loss-of-function DICER1 mutations in a human syndrome defined by the childhood lung neoplasm pleuropulmonary blastoma (PPB), which arises during lung development. DICER1 regulates many biological processes critical in development and disease pathogenesis. Significant challenges in defining the role of DICER1 in human disease are identifying cause-effect relationships and generating manipulatable systems that model the complexity of organ development and disease pathogenesis. Here we report the generation of a murine model for PPB and demonstrate that precise temporal and cell type-specific Dicer1 ablation is necessary and sufficient for the development of cystic lungs that histologically and phenotypically model PPB. Dicer1 ablation in the distal airway epithelium during early stages of lung development resulted in a cystic lung phenotype indistinguishable from PPB, whereas DICER1 function was not required for development of the proximal airway epithelium or during later stages of organogenesis. Mechanistic studies demonstrate that Dicer1 loss results in epithelial cell death, followed by cystic airway dilatation accompanied by epithelial and mesenchymal proliferation. These studies define precise temporal and epithelial cell type-specific DICER1 functions in the developing lung and demonstrate that loss of these DICER1 functions is sufficient for the development of cystic PPB. These results also provide evidence that PPB arise through a novel mechanism of non-cell-autonomous tumour initiation, in which the genetic abnormality initiating the neoplasm does not occur in the cells that ultimately transform, but rather occurs in a benign-appearing epithelial cell component that predisposes underlying mesenchymal cells to malignant transformation.


Asunto(s)
ARN Helicasas DEAD-box/metabolismo , Mutación de Línea Germinal/genética , Neoplasias Pulmonares/metabolismo , Blastoma Pulmonar/metabolismo , Ribonucleasa III/metabolismo , Animales , ARN Helicasas DEAD-box/genética , Modelos Animales de Enfermedad , Epitelio/metabolismo , Epitelio/patología , Humanos , Neoplasias Pulmonares/patología , Ratones , Blastoma Pulmonar/patología , Ribonucleasa III/genética
17.
Synth Commun ; 44(7): 976-980, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25221359

RESUMEN

The use of the Mitsunobu reaction for the synthesis of N,N-diethylbenzamides affords ortho-, meta-, and para-substituted benzamides, containing both electron-donating and electron-withdrawing groups. While the preparation of numerous functional groups has been efficiently demonstrated employing the Mitsunobu reaction, our methodology represents the first application of the Mitsunobu reaction for the construction of benzamides using benzoic acid and amine starting materials. Moreover, this synthetic transformation is believed to proceed via a non-classical mechanism involving the existence of an acyloxyphosphonium ion.

18.
Curr Alzheimer Res ; 10(7): 732-41, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23905997

RESUMEN

This paper investigates how commonly prescribed pharmacologic treatments for Alzheimer's disease (AD) affect Event-Related Potential (ERP) biomarkers as tools for predicting AD conversion in individuals with Mild Cognitive Impairment (MCI). We gathered baseline ERP data from two MCI groups (those taking AD medications and those not) and later determined which subjects developed AD (Convert->AD) and which subjects remained cognitively stable (Stable). We utilized a previously developed and validated multivariate system of ERP components to measure medication effects among these four subgroups. Discriminant analysis produced classification scores for each individual as a measure of similarity to each clinical group (Convert->AD, Stable), and we found a large significant main Group effect but no main AD Medications effect and no Group by Medications interaction. This suggested AD medications have negligible influence on this set of ERP components as weighted markers of disease progression. These results provide practical information to those using ERP measures as a biomarker to identify and track AD in individuals in a clinical or research setting.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/fisiopatología , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/fisiopatología , Progresión de la Enfermedad , Potenciales Evocados/fisiología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Disfunción Cognitiva/patología , Electroencefalografía/efectos de los fármacos , Electroencefalografía/métodos , Potenciales Evocados/efectos de los fármacos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Nootrópicos/farmacología , Nootrópicos/uso terapéutico , Resultado del Tratamiento
19.
J Alzheimers Dis ; 33(1): 55-68, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22886016

RESUMEN

Brain plasticity and cognitive compensation in the elderly are of increasing interest, and Alzheimer's disease (AD) offers an opportunity to elucidate how the brain may overcome damage. We provide neurophysiological evidence of a short-latency event-related potential (ERP) component (C145) linked to stimulus relevancy that may reflect cognitive compensation in early-stage AD. Thirty-six subjects with early-stage, mild AD and 36 like-aged normal elderly (controls) had their EEG recorded while performing our Number-Letter task, a cognitive/perceptual paradigm that manipulates stimulus relevancies. ERP components, including C145, were extracted from ERPs using principal components analysis. C145 amplitudes and spatial distributions were compared among controls, AD subjects with high performance on the Number-Letter task, and AD subjects with low performance. Compared to AD subjects, control subjects showed enhanced C145 processing of visual stimuli in the occipital region where differential processing of relevant stimuli occurred. AD high performers recruited central brain areas in processing task relevancy. Controls and AD low performers did not show a significant task relevancy effect in these areas. We conclude that short-latency ERP components can detect electrophysiological differences in early-stage AD that reflect altered cognition. Differences in C145 amplitudes between AD and normal elderly groups regarding brain locations and types of task effects suggest compensatory mechanisms can occur in the AD brain to overcome loss of normal functionality, and this early compensation may have a profound effect on the cognitive efficiency of AD individuals.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Trastornos del Conocimiento/fisiopatología , Electroencefalografía/métodos , Potenciales Evocados/fisiología , Pruebas Neuropsicológicas , Tiempo de Reacción/fisiología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Encéfalo/fisiología , Cognición/fisiología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Análisis de Componente Principal/métodos
20.
PLoS One ; 7(9): e46044, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23029379

RESUMEN

Stress is the most commonly reported precipitating factor for seizures in patients with epilepsy. Despite compelling anecdotal evidence for stress-induced seizures, animal models of the phenomena are sparse and possible mechanisms are unclear. Here, we tested the hypothesis that increased levels of the stress-associated hormone corticosterone (CORT) would increase epileptiform activity and spontaneous seizure frequency in mice rendered epileptic following pilocarpine-induced status epilepticus. We monitored video-EEG activity in pilocarpine-treated mice 24/7 for a period of four or more weeks, during which animals were serially treated with CORT or vehicle. CORT increased the frequency and duration of epileptiform events within the first 24 hours of treatment, and this effect persisted for up to two weeks following termination of CORT injections. Interestingly, vehicle injection produced a transient spike in CORT levels - presumably due to the stress of injection - and a modest but significant increase in epileptiform activity. Neither CORT nor vehicle treatment significantly altered seizure frequency; although a small subset of animals did appear responsive. Taken together, our findings indicate that treatment of epileptic animals with exogenous CORT designed to mimic chronic stress can induce a persistent increase in interictal epileptiform activity.


Asunto(s)
Antiinflamatorios/farmacología , Corticosterona/farmacología , Convulsiones/tratamiento farmacológico , Estado Epiléptico/inducido químicamente , Estado Epiléptico/fisiopatología , Animales , Antiinflamatorios/sangre , Antiinflamatorios/metabolismo , Corticosterona/sangre , Corticosterona/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Pilocarpina , Estado Epiléptico/sangre , Estrés Fisiológico
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