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1.
Alzheimer Dis Assoc Disord ; 38(2): 160-167, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38748658

RESUMEN

INTRODUCTION: Enrolling individuals from underrepresented ethnoracial groups in aging research is often a challenge. METHODS: We sought a diverse sample of older adults from a small-town area for a longitudinal aging study. We employed an intensive community engagement approach encompassing a range of recruitment strategies. RESULTS: Over 4 years a steady trickle of individuals, 66% self-identifying as Black, signed up for study information; the proportion of those who eventually enroll in the study has been rising each year, from 68% to 94%. Community events, word-of-mouth referrals, and mailed postcards brought in the most contacts. The highest percentage of contacts who ultimately enrolled were from postcards, flyers, and word-of-mouth. Significantly more word-of-mouth referrals were endorsed by Black individuals than White and by Black men than other race/sex groups. CONCLUSIONS: We have had some success in building relationships and trust with the local community, enrolling Black study participants in a proportion equal to their representation in the target community using a variety of recruitment methods. Patience, immersion in the community, and partnerships with key community members alongside traditional advertisements, and the utilization of study participants as recruiters are critical to designing optimal, targeted, recruitment strategies.


Asunto(s)
Envejecimiento , Selección de Paciente , Humanos , Estudios Longitudinales , Masculino , Femenino , Anciano , Anciano de 80 o más Años , Estudios de Cohortes
2.
Behav Res Methods ; 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012511

RESUMEN

Gestures are ubiquitous in human communication, and a growing but inconsistent body of research suggests that people with autism spectrum disorder (ASD) may process co-speech gestures differently from neurotypical individuals. To facilitate research on this topic, we created a database of 162 gesture videos that have been normed for comprehensibility by both autistic and non-autistic raters. These videos portray an actor performing silent gestures that range from highly meaningful (e.g., iconic gestures) to ambiguous or meaningless. Each video was rated for meaningfulness and given a one-word descriptor by 40 autistic and 40 non-autistic adults, and analyses were conducted to assess the level of within- and across-group agreement. Across gestures, the meaningfulness ratings provided by raters with and without ASD correlated at r > 0.90, indicating a very high level of agreement. Overall, autistic raters produced a more diverse set of verbal labels for each gesture than did non-autistic raters. However, measures of within-gesture semantic similarity among the responses provided by each group did not differ, suggesting that increased variability within the ASD group may have occurred at the lexical rather than semantic level. This study is the first to compare gesture naming between autistic and non-autistic individuals, and the resulting dataset is the first gesture stimulus set for which both groups were equally represented in the norming process. This database also has broad applicability to other areas of research related to gesture processing and comprehension. The video database and accompanying norming data are available on the Open Science Framework.

3.
Am J Med Genet A ; 188(1): 178-186, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34562062

RESUMEN

Children with autism spectrum disorder (ASD) routinely undergo genetic testing (GT) to identify the causative genetic etiology of their ASD. As there are questions about the impact of GT beyond clinical diagnosis, we conducted a mixed methods study to assess the perceived benefits of GT by exploring factors that lead parents to pursue these tests and the benefits experienced. Respondents were part of a pretest or posttest group. The pretest group (N = 22) expressed intent to pursue GT and the posttest group (N = 32) had undergone GT and received results at least 3 months prior to completing the survey. Responses were compared between and within groups. Free text responses were coded for themes and selection questions were analyzed using Fisher's exact tests. Our results demonstrate significant differences between the groups with participants in the pretest group more likely to choose "increased access to therapies" (p = 0.026) and "improved healthcare" (p < 0.000) as reasons to pursue testing. Benefits were also significantly different with "improved healthcare" (p = 0.009), "improved access to services" (p = 0.012), and "improved access to therapies" (p = 0.003) more frequently anticipated by the pretest group than reported by the posttest group. A relationship between GT and clinical management changes was reported by 34.4-50.0% of the posttest group. Among that group, genetic result type (positive, negative, or variant of uncertain significance) was associated with differing perceived benefits of testing. Thematic analysis revealed increased knowledge and coping as reported benefits in both groups. Our findings indicate a discrepancy between parental expectations and experiences of GT. Comprehensive pretest and posttest genetic counseling are necessary to improve information retention, address potential outcomes, and set expectations of GT for parents of children with ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/genética , Niño , Asesoramiento Genético , Pruebas Genéticas/métodos , Humanos , Padres/psicología , Encuestas y Cuestionarios
4.
Aesthetic Plast Surg ; 45(2): 453-458, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32968821

RESUMEN

BACKGROUND: Three-dimensional (3D) nipple-areolar tattoo is a novel approach to nipple-areolar complex reconstruction for which little data exist. Our aim was to evaluate 3D nipple-areolar tattoo outcomes and investigate if patient factors, payer status, surgeries, or therapies affect tattoo utilization. METHODS: Patients pursuing skin-sparing (SSM) or attempted nipple-sparing mastectomy (NSM) with breast reconstruction from 2008 to 2019 were reviewed. Outcomes included frequency of 3D tattoo, post-procedure complications (infections, or other local adverse sequelae), and rates, indications, and timing of revisions. Patient factors, payer status, surgeries, and adjuvant therapies underwent univariate analysis comparing rates of 3D tattoo and revisions. RESULTS: A total of 191 patients were identified; median follow-up was 4 years. The majority of patients were white (165, 86%), married (146, 76%), and post-menopausal (97, 51%), with private insurance (156, 81%). Surgeries included SSM (172, 90%) or attempted NSM (19, 10%) with implant (154, 81%) or autologous reconstruction (37, 19%). Sixty-two patients (32%) underwent 3D nipple-areolar tattooing. No post-procedure complications occurred. After tattooing, 20 patients (32%) pursued revisions, the majority due to color fading (12, 60%). Average time from tattoo to completion of revisions was 5.6 months. Patients undergoing autologous reconstruction had a higher rate of 3D tattooing (p < 0.001). Adjuvant radiation led to a higher rate of revisions (p = 0.02). Patient factors, payer status, index mastectomy, and chemotherapy did not significantly affect rates of 3D tattooing or revisions. CONCLUSIONS: 3D nipple-areolar tattoo utilization is likely unaffected by age, marriage, menopause, or payer status. Radiotherapy and color fading can lead to more revisions. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Asunto(s)
Neoplasias de la Mama , Mamoplastia , Tatuaje , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mamoplastia/efectos adversos , Mastectomía , Pezones/cirugía , Satisfacción del Paciente , Estudios Retrospectivos
5.
Cogn Neuropsychiatry ; 25(5): 371-386, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32873177

RESUMEN

Introduction: Schizotypy is defined as personality traits reflecting an underlying risk for schizophrenia-spectrum disorders. As yet, there is a dearth of suitable objective markers for measuring schizotypy. Frontal alpha asymmetry, characterised by reduced left versus right frontal region activity, reflects trait-like diminished approach-related systems and has been found in schizophrenia. Methods: The present study used electroencephalography (EEG) recorded on a consumer-grade mobile headset to examine asymmetric resting-state frontal alpha, beta, and gamma power within the multidimensional schizotypy (e.g. positive, negative, disorganised) during a three-minute "eyes closed" resting period in college undergraduates (n=49). Results: Findings suggest that schizotypy was exclusively related to reduced left versus right-lateralised power in the alpha frequency (8.1-12.9 Hz., R2= .16). Follow-up analysis suggested that positive schizotypy was uniquely associated with increased right alpha activity, indicating increased withdrawal motivation. Conclusions: Frontal asymmetry is a possible ecologically valid objective marker for schizotypy that may be detectable using easily accessible, consumer-grade technology.


Asunto(s)
Esquizofrenia , Trastorno de la Personalidad Esquizotípica , Electroencefalografía/métodos , Lóbulo Frontal/fisiología , Humanos , Motivación
6.
J Cogn Neurosci ; 31(2): 186-201, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30188777

RESUMEN

It is well established that the hippocampus is critical for memory. Recent evidence suggests that one function of hippocampal memory processing is to optimize how people actively explore the world. Here we demonstrate that the link between the hippocampus and exploration extends even to the moment-to-moment use of eye movements during visuospatial memory encoding. In Experiment 1, we examined relationships between study-phase eye movements in healthy individuals and subsequent performance on a spatial reconstruction test. In addition to quantitative measures of viewing behaviors (e.g., how many fixations or saccades were deployed during study), we used the information-theoretic measure of entropy to assess the amount of randomness or disorganization in participants' scanning behaviors. We found that the use of scanpaths during study that were lower in entropy (e.g., more organized, less random) predicted more accurate spatial reconstruction both within and between participants. Scanpath entropy was a better predictor of reconstruction accuracy than were the quantitative measures of viewing. In Experiment 2, we found that individuals with hippocampal amnesia tended to engage in viewing patterns that were higher in entropy (less organized) relative to healthy comparisons. These findings reveal a critical role of the hippocampus in guiding eye movement exploration to optimize visuospatial relational memory.


Asunto(s)
Conducta Exploratoria/fisiología , Hipocampo/fisiología , Memoria/fisiología , Reconocimiento Visual de Modelos/fisiología , Desempeño Psicomotor/fisiología , Movimientos Sacádicos/fisiología , Percepción Espacial/fisiología , Adolescente , Adulto , Entropía , Medidas del Movimiento Ocular , Femenino , Fijación Ocular/fisiología , Humanos , Masculino , Adulto Joven
7.
J Biol Inorg Chem ; 24(8): 1261-1268, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31728738

RESUMEN

Metal dyshomeostasis has long been linked to Parkinson's disease (PD), and the amyloidogenic protein α-synuclein (αS) is universally recognized as a key player in PD pathology. Structural consequences upon coordination of copper and iron to αS have gained attention due to significant dyshomeostasis of both metals in the PD brain. Protein-metal association can navigate protein folding in distinctive pathways based on the identity of the bio-metal in question. In this work, we employed photo-chemical crosslinking of unmodified proteins (PICUP) to evaluate these potential metal ion-induced structural alterations in the folding dynamics of N-terminally acetylated αS (NAcαS) following metal coordination. Through fluorescence analysis and immunoblotting analyses following photoirradiation, we discovered that coordination of iron obstructs copper-promoted crosslinking. The absence of intra-molecular crosslinking upon iron association further supports its C-terminal coordination site and suggests a potential role for iron in mitigating nearby post-translational modification of tyrosine residues. Decreased fluorescence emission upon synergistic coordination of both copper and iron highlighted that although copper acts as a conformational promotor of NAcαS crosslinking, iron inhibits analogous conformational changes within the protein. The metal coordination preferences of NAcαS suggest that both competitive binding sites as well as dual metal coordination contribute to the changes in folding dynamics, unveiling unique structural orientations for NAcαS that have a direct and measureable influence on photoinitiated dityrosine crosslinks. Moreover, our findings have physiological implications in that iron overload, as is associated with PD-insulted brain tissue, may serve as a conformational block of copper-promoted protein oxidation.


Asunto(s)
Cobre/metabolismo , Hierro/metabolismo , Conformación Proteica/efectos de los fármacos , alfa-Sinucleína/metabolismo , Sulfato de Amonio/química , Complejos de Coordinación , Reactivos de Enlaces Cruzados/síntesis química , Reactivos de Enlaces Cruzados/efectos de la radiación , Fluorescencia , Luz , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/efectos de la radiación , Oxidación-Reducción , Procesos Fotoquímicos , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/efectos de la radiación , Unión Proteica , Tirosina/análogos & derivados , Tirosina/análisis , alfa-Sinucleína/química
8.
J Am Chem Soc ; 140(49): 17086-17094, 2018 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-30422655

RESUMEN

Aggregation of the neuronal protein α-synuclein (αS) is a critical factor in the pathogenesis of Parkinson's disease. Analytical methods to detect post-translational modifications of αS are under development, yet the mechanistic underpinnings of biomarkers like dityrosine formation within αS have yet to be established. In our work, we demonstrate that CuI-bound N-terminally acetylated αS (NAcαS) activates O2 resulting in both intermolecular dityrosine cross-linking within the fibrillar core as well as intramolecular cross-linking within the C-terminal region. Substitution of the H50 residue with a disease relevant Q mutation abolishes intermolecular dityrosine cross-linking and limits the CuI/O2 promoted cross-linking to the C-terminal region. Such a dramatic change in reaction behavior establishes a previously unidentified role for H50 in facilitating intermolecular cross-linking. Involvement of H50 in the reaction profile implies that long-range histidine coordination with the upstream CuI coordination site is necessary to stabilize the transition of CuI to CuII as is a required mechanistic outcome of CuI/O2 reactivity. The aggregation propensity of NAcH50Q-CuI is also enhanced in comparison to NAcαS-CuI, suggesting a potential functional role for both copper and intermolecular cross-linking in attenuating NAcαS fibrillization.


Asunto(s)
Cobre/química , Radicales Libres/química , Histidina/química , alfa-Sinucleína/metabolismo , Acetilación , Secuencia de Aminoácidos , Complejos de Coordinación/química , Humanos , Mutación , Oxígeno/química , Conformación Proteica , Multimerización de Proteína , Tirosina/química , alfa-Sinucleína/química , alfa-Sinucleína/genética
9.
J Am Chem Soc ; 140(15): 5028-5032, 2018 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-29608844

RESUMEN

Brain metal dyshomeostasis and altered structural dynamics of the presynaptic protein α-synuclein (αS) are both implicated in the pathology of Parkinson's disease (PD), yet a mechanistic understanding of disease progression in the context of αS structure and metal interactions remains elusive. In this Communication, we detail the influence of iron, a prevalent redox-active brain biometal, on the aggregation propensity and secondary structure of N-terminally acetylated αS (NAcαS), the physiologically relevant form in humans. We demonstrate that under aerobic conditions, Fe(II) commits NAcαS to a PD-relevant oligomeric assembly, verified by the oligomer-selective A11 antibody, that does not have any parallel ß-sheet character but contains a substantial right-twisted antiparallel ß-sheet component based on CD analyses and descriptive deconvolution of the secondary structure. This NAcαS-FeII oligomer does not develop into the ß-sheet fibrils that have become hallmarks of PD, even after extended incubation, as verified by TEM imaging and the fibril-specific OC antibody. Thioflavin T (ThT), a fluorescent probe for ß-sheet fibril formation, also lacks coordination to this antiparallel conformer. We further show that this oligomeric state is not observed when O2 is excluded, indicating a role for iron(II)-mediated O2 chemistry in locking this dynamic protein into a conformation that may have physiological or pathological implications.


Asunto(s)
Compuestos Ferrosos/metabolismo , alfa-Sinucleína/metabolismo , Benzotiazoles , Compuestos Ferrosos/química , Colorantes Fluorescentes/química , Humanos , Oxidación-Reducción , Enfermedad de Parkinson/metabolismo , Tiazoles/química , alfa-Sinucleína/química
10.
Hippocampus ; 28(2): 164-177, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29232494

RESUMEN

Hippocampal involvement in learning and remembering relational information has an extensive history, often focusing specifically on spatial information. In humans, spatial reconstruction (SR) paradigms are a powerful tool for evaluating an individuals' spatial-relational memory. In SR tasks, participants study locations of items in space and subsequently reconstruct the studied display after a short delay. Previous work has revealed that patients with hippocampal damage are impaired both in overall placement accuracy as well as on a specific measure of relational memory efficacy, "swaps" (i.e., when the relative location of two items is reversed). However, the necessity of the hippocampus for other types of spatial-relational information involved in reconstruction behaviors (e.g., where in the environment and relative to which other items an item was located) have not yet been investigated systematically. In this work, three patients with hippocampal damage and nine healthy matched comparison participants performed an SR task. An analysis framework was developed to independently assess three first-order types of relations: (1) memory for the binding of specific item identities to locations, (2) memory for arrangement of items in relation to each other or the environment bounds, regardless of memory for the item identity, and (3) higher-order, compound relational errors (i.e., errors involving multiple pieces of relational information). Reconstruction errors were evaluated to determine the degree to which patients and comparisons differed (or not) on each type of spatial-relational information. Data revealed that the primary group difference in performance was for identity-location information. However, when the locations of items were evaluated without regarding the identities, no group difference was found in the number of item placements to studied locations. The present work provides a principled approach to analysis of SR data and clarifies our understanding of the types of spatial relations impaired in hippocampal damaged.


Asunto(s)
Amnesia/patología , Mapeo Encefálico , Hipocampo/patología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Amnesia/diagnóstico por imagen , Amnesia/fisiopatología , Amnesia/psicología , Análisis de Varianza , Femenino , Hipocampo/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
11.
Ann Surg ; 267(1): 81-87, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27759619

RESUMEN

OBJECTIVE: To characterize reasons for discordance between administrative data and registry data in the determination of postoperative infectious complications. BACKGROUND: Data regarding the occurrence of postoperative surgical complications are identified through either administrative or registry data. Rates of complications vary significantly between these two types of data; the reasons for this are not well-understood. METHODS: The occurrence of 30-day inpatient infectious complications (pneumonia, sepsis, surgical site infection, and urinary tract infection) was compared between the NSQIP and administrative mechanisms at 4 academic hospitals between 2012 and 2014. In each situation where the NSQIP and administrative data were discordant regarding the occurrence of a specific complication, a 2-clinician chart abstraction was performed to characterize the reasons for discordance as (i) administrative coding error, (ii) NSQIP coding error, (iii) "question of criteria", where the discordance was the result of differences in criteria, or (iv) "dually incorrect", where both data sources coded the complication incorrectly. RESULTS: The cohort included 19,163 patients undergoing surgery in 4 different academic hospitals. Rates of infectious complications varied up to 5-fold between the two data sources. A total of 717 discordant complications were identified. Of these, the greatest portion (43%) was due to "question of criteria," followed by administrative coding error (37%), NSQIP error (15%), and dually incorrect (5%). CONCLUSIONS: With a goal of improving existing mechanisms for measuring surgical quality, definitions for the occurrence of a postoperative complication need to be developed and applied consistently. Progress toward this goal will enable patients and payers to better take advantage of recent advances in healthcare data transparency.


Asunto(s)
Administración Hospitalaria/estadística & datos numéricos , Registros de Hospitales , Pacientes Internos , Sistema de Registros , Infección de la Herida Quirúrgica/epidemiología , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos/epidemiología
12.
Protein Expr Purif ; 152: 146-154, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30041032

RESUMEN

Parkinson's disease (PD) is multifactorial, likely resulting from an intricate relationship of genetic and environmental factors affecting fundamental cellular processes. Histopathological hallmarks of PD include the development of granular inclusions known as Lewy bodies that are enriched with aggregates of the protein α-synuclein (αS). Historically, αS has been considered a natively unfolded protein prone to amyloidogenic behavior. However, recent studies have revealed a physiologically relevant folded αS tetramer that is both alpha-helical and aggregation-resistant. The two forms are thought to reside in a dynamic coexistence within cells, and it has been suggested that a shift from metastable tetramers to the monomeric form could serve as a mechanism for disease initiation. The underlying pathology causing this type of shift remains unknown, but the importance of understanding tetramer stability and disassembly has therapeutic potential that cannot be overemphasized. Isolation of tetrameric αS is complicated by its dynamic nature, so thorough and detailed biochemical and biophysical studies on this αS conformer have been hampered by accessibility issues. We now report a robust and reliable recombinant expression platform that enables purification of native tetrameric αS without any detergents or other structure-modifying additives.


Asunto(s)
Clonación Molecular/métodos , Acetiltransferasa B N-Terminal/metabolismo , Plásmidos/química , Modificación Traduccional de las Proteínas , alfa-Sinucleína/aislamiento & purificación , Acetilación , Cromatografía en Gel/métodos , Cromatografía por Intercambio Iónico/métodos , Reactivos de Enlaces Cruzados/química , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Glutaral/química , Humanos , Acetiltransferasa B N-Terminal/genética , Plásmidos/metabolismo , Conformación Proteica , Multimerización de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Schizosaccharomyces/química , Schizosaccharomyces/enzimología , alfa-Sinucleína/química , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
13.
Environ Sci Technol ; 52(7): 4275-4284, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29513011

RESUMEN

Efficient oxidation from arsenite [As(III)] to arsenate [As(V)], which is less toxic and more readily to be adsorbed by adsorbents, is important for the remediation of arsenic pollution. In this paper, we report a metal organic framework (MIL-100(Fe)) filter to efficiently remove arsenic from synthetic groundwater. With commercially available iron mesh as a substrate, MIL-100(Fe) is implanted through an in situ growth method. MIL-100(Fe) is able to capture As(III) due to its microporous structure, superior surface area, and ample active sites for As adsorption. This approach increases the localized As concentration around the filter, where Fenton-like reactions are initiated by the Fe2+/Fe3+ sites within the MIL-100(Fe) framework to oxidize As(III) to As(V). The mechanism was confirmed by colorimetric detection of H2O2, fluorescence, and electron paramagnetic resonance detection of ·OH. With the aid of oxygen bubbling and Joule heating, the removal efficiency of As(III) can be further boosted. The MIL-100(Fe)-based filter also exhibits satisfactory structural stability and recyclability. Notably, the adsorption capacity of the filter can be regenerated satisfactorily. Our results demonstrate the potential of this filter for the efficient remediation of As contamination in groundwater.


Asunto(s)
Arsénico , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Peróxido de Hidrógeno , Hierro , Mallas Quirúrgicas
14.
Ann Plast Surg ; 78(2): e1-e3, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27070686

RESUMEN

A question arose in our practice of whether all cysts considered sebaceous should be sent for pathologic evaluation. To address this controversial topic, we performed a retrospective study of our single institution's histopathology database. A natural language search of the CoPath database across the institution was undertaken using the diagnosis of sebaceous cyst, epidermal cyst, epidermoid cyst, epithelial cyst, infundibular cyst, pilar cyst, trichilemmal cyst, and steatocystoma. A surgical pathologic review of all specimens with one of these preexcision diagnoses was included in the 15-year retrospective study of 1998 to 2013. All slides were confirmed to have undergone histopathologic review, and the preexcision diagnoses were compared with the postexcision diagnoses. Chart review was undertaken in instances of a diagnosis of malignancy. A total of 13,746 samples were identified. Forty-eight specimens had histopathologic diagnosis of malignancy, for an incidence of 0.3% and with the most common malignancy being squamous cell carcinoma. Chart review showed that for all cases, the surgeons reported uncertainty with regard to the diagnosis because of history or physical characteristics, or both. In addition, a comprehensive literature review showed results consistent with our data and illustrated 19 cases during the past 10 years in which most of the findings were squamous cell carcinoma. We propose the recommendation that routine pathologic evaluation of sebaceous cysts is necessary only when clinical suspicion exists.


Asunto(s)
Quiste Epidérmico/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/diagnóstico , Carcinoma/patología , Carcinoma/cirugía , Bases de Datos Factuales , Diagnóstico Diferencial , Quiste Epidérmico/diagnóstico , Quiste Epidérmico/cirugía , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/patología , Linfoma de Células B/cirugía , Melanoma/diagnóstico , Melanoma/patología , Melanoma/cirugía , Persona de Mediana Edad , Neoplasias de Células Plasmáticas/diagnóstico , Neoplasias de Células Plasmáticas/patología , Neoplasias de Células Plasmáticas/cirugía , Estudios Retrospectivos
15.
Angew Chem Int Ed Engl ; 53(19): 4935-9, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24700427

RESUMEN

Synthesis of small-molecule Cu2 O2 adducts has provided insight into the related biological systems and their reactivity patterns including the interconversion of the Cu(II) 2 (µ-η(2) :η(2) -peroxo) and Cu(III) 2 (µ-oxo)2 isomers. In this study, absorption spectroscopy, kinetics, and resonance Raman data show that the oxygenated product of [(BQPA)Cu(I) ](+) initially yields an "end-on peroxo" species, that subsequently converts to the thermodynamically more stable "bis-µ-oxo" isomer (Keq =3.2 at -90 °C). Calibration of density functional theory calculations to these experimental data suggest that the electrophilic reactivity previously ascribed to end-on peroxo species is in fact a result of an accessible bis-µ-oxo isomer, an electrophilic Cu2 O2 isomer in contrast to the nucleophilic reactivity of binuclear Cu(II) end-on peroxo species. This study is the first report of the interconversion of an end-on peroxo to bis-µ-oxo species in transition metal-dioxygen chemistry.


Asunto(s)
Cobre/química , Oxígeno/química , Espectrofotometría Ultravioleta , Espectrometría Raman
16.
Neuroimage ; 83: 849-61, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23871869

RESUMEN

The mechanisms that give rise to familiarity memory have received intense research interest. One current topic of debate concerns the extent to which familiarity is driven by the same fluency sources that give rise to certain implicit memory phenomena. Familiarity may be tied to conceptual fluency, given that familiarity and conceptual implicit memory can exhibit similar neurocognitive properties. However, familiarity can also be driven by perceptual factors, and its neural basis under these circumstances has received less attention. Here we recorded brain potentials during recognition testing using a procedure that has previously been shown to encourage a reliance on letter information when assessing familiarity for words. Studied and unstudied words were derived either from two separate letter pools or a single letter pool ("letter-segregated" and "normal" conditions, respectively) in a within-subjects contrast. As predicted, recognition accuracy was higher in the letter-segregated relative to the normal condition. Electrophysiological analyses revealed parietal old-new effects from 500-700 ms in both conditions. In addition, a topographically dissociable occipital old-new effect from 300-700 ms was present in the letter-segregated condition only. In a second experiment, we found that similar occipital brain potentials were associated with confident false recognition of words that shared letters with studied words but were not themselves studied. These findings indicate that familiarity is a multiply determined phenomenon, and that the stimulus dimensions on which familiarity is based can moderate its neural correlates. Conceptual and perceptual contributions to familiarity vary across testing circumstances, and both must be accounted for in theories of recognition memory and its neural basis.


Asunto(s)
Encéfalo/fisiología , Memoria/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Mapeo Encefálico , Electrofisiología , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Estimulación Luminosa , Procesamiento de Señales Asistido por Computador , Adulto Joven
17.
Adv Exp Med Biol ; 765: 131-138, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22879025

RESUMEN

The vascular hypothesis of Alzheimer's disease (AD) considers cerebral hypoperfusion as a primary trigger for neuronal dysfunction. We have previously reported that red blood cells (RBCs) bind amyloid, which are the characteristic deposits found in AD brains, and interact with amyloid on the vasculature [1-3]. Oxidative stress triggered by these RBC/amyloid interactions could impair oxygen delivery. Recent literature has implicated copper bound amyloid-ß peptide (CuAß) and the associated production of reactive oxygen species (ROS) as one of the primary factors contributing to AD pathology. In this work, we have investigated CuAß generated RBC oxidative stress. Aß(1-40) peptide with a stoichiometric amount of copper bound was produced and compared to the metal-free form of the peptide. Different aggregation states of the peptides were isolated and incubated with RBCs for 15 h. Interestingly, CuAß stimulated a pronounced increase in red cell oxidative stress as indicated by increased hemoglobin (Hb) oxidation, increased formation of fluorescent heme degradation products, and a decrease in RBC deformability. These findings demonstrate a potential role for CuAß in promoting vascular oxidative stress leading to impaired cerebral oxygen delivery, which may contribute to neurodegeneration associated with AD.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Péptidos beta-Amiloides/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Cobre/metabolismo , Eritrocitos/metabolismo , Oxígeno/metabolismo , Humanos , Oxidación-Reducción , Estrés Oxidativo , Oxihemoglobinas/química , Oxihemoglobinas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
18.
J Exp Psychol Hum Percept Perform ; 49(6): 786-801, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37166935

RESUMEN

Humans use eye movements to build visual memories. We investigated how the contributions of specific viewing behaviors to memory formation evolve over individual study epochs. We used dyadic modeling to explain performance on a spatial reconstruction task based on interactions among two gaze measures: (a) the entropy of the scanpath and (b) the frequency of item-to-item gaze transitions. To measure these interactions, our hypothesized model included causal pathways by which early-trial viewing behaviors impacted subsequent memory via downstream effects on later viewing. We found that lower scanpath entropy throughout the trial predicted better memory performance. By contrast, the effect of item-to-item transition frequency changed from negative to positive as the trial progressed. The model also revealed multiple pathways by which early-trial viewing dynamically altered late-trial viewing, thereby impacting memory indirectly. Finally, individual differences in scores on an independent measure of memory ability were found to predict viewing effectiveness, and viewing behaviors partially mediated the relation between memory ability and reconstruction accuracy. In a second experiment, the model showed a good fit for an independent dataset. These results highlight the dynamic nature of memory formation and suggest that the order in which eye movements occur can critically determine their effectiveness. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Movimientos Oculares , Memoria , Humanos , Cognición , Individualidad
19.
Biol Psychol ; 178: 108528, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36868296

RESUMEN

Previous research is inconclusive on when visual working memory (VWM) can be object-based or feature-based. Prior event-related potential (ERP) studies using change detection tasks have found that amplitudes of the N200-an ERP index of VWM comparison- are sensitive to changes in both relevant and irrelevant features, suggesting a bias toward object-based processing. To test whether VWM comparison processing can operate in a feature-based manner, we aimed to create circumstances that would support feature-based processing by: 1) using a strong task-relevance manipulation, and 2) repeating features within a display. Participants completed two blocks of a change detection task for four-item displays in which they were told to respond to color changes (task relevant) but not shape changes (task irrelevant). The first block contained only task-relevant changes to create a strong task-relevance manipulation. In the second block, both relevant and irrelevant changes were present. In both blocks, half of the arrays contained within-display feature repetitions (e.g. two items of the same color or shape). We found that during the second block, N200 amplitudes were sensitive to task-relevant but not irrelevant features regardless of repetition status, consistent with feature-based processing. However, analyses of behavioral data and N200 latencies suggested that object-based processing was occurring at some stages of VWM processing on task-irrelevant feature change trials. In particular, task-irrelevant changes may be processed after no task-relevant feature change is revealed. Overall, the results from the current study suggest that the VWM processing is flexible and can be either object- or feature-based.


Asunto(s)
Memoria a Corto Plazo , Percepción Visual , Humanos , Memoria a Corto Plazo/fisiología , Percepción Visual/fisiología , Potenciales Evocados
20.
J Psychosoc Oncol ; 30(3): 294-315, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22571245

RESUMEN

This study sought to examine the effects of an expressive talking intervention for 58 caregiving partners of hematopoietic stem cell transplant survivors, persons known to experience distress. Caregivers were randomly assigned to a three-session emotional expression (EE) or control condition. Subjective, objective, and physiologic indicators of emotion were assessed. Relative to controls, EE participants experienced more negative emotion, uttered more negative emotion words, and perceived the exercises as more helpful and meaningful. The trajectory of skin conductance and the use of cognitive mechanism words increased across EE sessions, suggesting sustained emotional engagement. Future research is warranted to determine the optimal dose and timing of EE for this population.


Asunto(s)
Cuidadores/psicología , Comunicación , Emoción Expresada , Trasplante de Células Madre Hematopoyéticas/psicología , Psicoterapia/métodos , Adaptación Psicológica , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Fenómenos Fisiológicos de la Piel , Estrés Psicológico , Sobrevivientes
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