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1.
Am J Respir Crit Care Med ; 209(12): 1463-1476, 2024 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358857

RESUMEN

Rationale: Acute cellular rejection (ACR) after lung transplant is a leading risk factor for chronic lung allograft dysfunction. Prior studies have demonstrated dynamic microbial changes occurring within the allograft and gut that influence local adaptive and innate immune responses. However, the lung microbiome's overall impact on ACR risk remains poorly understood. Objectives: To evaluate whether temporal changes in microbial signatures were associated with the development of ACR. Methods: We performed cross-sectional and longitudinal analyses (joint modeling of longitudinal and time-to-event data and trajectory comparisons) of 16S rRNA gene sequencing results derived from lung transplant recipient lower airway samples collected at multiple time points. Measurements and Main Results: Among 103 lung transplant recipients, 25 (24.3%) developed ACR. In comparing samples acquired 1 month after transplant, subjects who never developed ACR demonstrated lower airway enrichment with several oral commensals (e.g., Prevotella and Veillonella spp.) than those with current or future (beyond 1 mo) ACR. However, a subgroup analysis of those who developed ACR beyond 1 month revealed delayed enrichment with oral commensals occurring at the time of ACR diagnosis compared with baseline, when enrichment with more traditionally pathogenic taxa was present. In longitudinal models, dynamic changes in α-diversity (characterized by an initial decrease and a subsequent increase) and in the taxonomic trajectories of numerous oral commensals were more commonly observed in subjects with ACR. Conclusions: Dynamic changes in the lower airway microbiota are associated with the development of ACR, supporting its potential role as a useful biomarker or in ACR pathogenesis.


Asunto(s)
Rechazo de Injerto , Trasplante de Pulmón , Humanos , Trasplante de Pulmón/efectos adversos , Masculino , Rechazo de Injerto/microbiología , Femenino , Persona de Mediana Edad , Estudios Longitudinales , Estudios Transversales , Adulto , Microbiota , ARN Ribosómico 16S/genética , Pulmón/microbiología , Anciano , Enfermedad Aguda
2.
Biophys J ; 114(11): 2606-2616, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29874611

RESUMEN

The molecular interactions between antimicrobial peptides (AMPs) and lipid A-containing supported lipid bilayers were probed using single-molecule total internal reflection fluorescence microscopy. Hybrid supported lipid bilayers with lipid A outer leaflets and phospholipid (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE)) inner leaflets were prepared and characterized, and the spatiotemporal trajectories of individual fluorescently labeled LL37 and Melittin AMPs were determined as they interacted with the bilayer surfaces comprising either monophosphoryl or diphosphoryl lipid A (from Escherichia coli) to determine the impact of electrostatic interactions. Large numbers of trajectories were obtained and analyzed to obtain the distributions of surface residence times and the statistics of the spatial trajectories. Interestingly, the AMP species were sensitive to subtle differences in the charge of the lipid, with both peptides diffusing more slowly and residing longer on the diphosphoryl lipid A. Furthermore, the single-molecule dynamics indicated a qualitative difference between the behavior of AMPs on hybrid Lipid A bilayers and on those composed entirely of DOPE. Whereas AMPs interacting with a DOPE bilayer exhibited two-dimensional Brownian diffusion with a diffusion coefficient of ∼1.7 µm2/s, AMPs adsorbed to the lipid A surface exhibited much slower apparent diffusion (on the order of ∼0.1 µm2/s) and executed intermittent trajectories that alternated between two-dimensional Brownian diffusion and desorption-mediated three-dimensional flights. Overall, these findings suggested that bilayers with lipid A in the outer leaflet, as it is in bacterial outer membranes, are valuable model systems for the study of the initial stage of AMP-bacterium interactions. Furthermore, single-molecule dynamics was sensitive to subtle differences in electrostatic interactions between cationic AMPs and monovalent or divalent anionic lipid A moieties.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Lípido A/metabolismo , Membrana Dobles de Lípidos/metabolismo , Unión Proteica
3.
Brain Inj ; 30(12): 1491-1500, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27834537

RESUMEN

PRIMARY OBJECTIVE: Based on high comorbidity between mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) among deployed military service members, this study tested the hypothesis that the presence of PTSD disrupts the association between mTBI and lower white matter integrity identified in non-military samples. Research design/Methods and procedures: In a sample of 124 recent veterans with a range of mTBI and PTSD history, diffusion tensor imaging (DTI) metrics of white matter integrity in 20 regions were compared using multiple mTBI and PTSD contrasts. MAIN OUTCOMES AND RESULTS: Civilian mTBI was associated with lower global anisotropy, higher global diffusivity and higher diffusivity in 17 of 20 regions. No main effects of deployment mTBI were observed, but an interaction between deployment mTBI and lifetime PTSD on FA was observed globally and in 10 regions. Impact and blast mTBI demonstrated similar but weaker effects to those of civilian and deployment mTBI, respectively, demonstrating the context of mTBI is more relevant to white matter integrity than mechanism of injury. CONCLUSIONS: Overall, a main effect of civilian mTBI indicates long-term disruptions to white matter are likely present, while the interaction between deployment mTBI and PTSD indicates that a history of PTSD alters this relationship.


Asunto(s)
Conmoción Encefálica/complicaciones , Conmoción Encefálica/epidemiología , Corteza Cerebral/patología , Leucoencefalopatías/etiología , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/epidemiología , Adulto , Campaña Afgana 2001- , Anisotropía , Conmoción Encefálica/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Guerra de Irak 2003-2011 , Leucoencefalopatías/diagnóstico por imagen , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Índices de Gravedad del Trauma , Estados Unidos/epidemiología , Veteranos/psicología
4.
Br J Psychiatry ; 206(3): 237-44, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25614533

RESUMEN

BACKGROUND: Estimates of the prevalence of mild traumatic brain injury (mTBI) among military personnel and combat veterans rely almost exclusively on retrospective self-reports; however, reliability of these reports has received little attention. AIMS: To examine the consistency of reporting of mTBI over time and identify factors associated with inconsistent reporting. METHOD: A longitudinal cohort of 948 US National Guard Soldiers deployed to Iraq completed self-report questionnaire screening for mTBI and psychological symptoms while in-theatre 1 month before returning home (time 1, T1) and 1 year later (time 2, T2). RESULTS: Most respondents (n = 811, 85.5%) were consistent in their reporting of mTBI across time. Among those who were inconsistent in their reports (n = 137, 14.5%), the majority denied mTBI at T1 and affirmed mTBI at T2 (n = 123, 89.8%). Respondents rarely endorsed mTBI in-theatre and later denied mTBI (n = 14, 10.2% of those with inconsistent reports). Post-deployment post-traumatic stress symptoms and non-specific physical complaints were significantly associated with inconsistent report of mTBI. CONCLUSIONS: Military service members' self-reports of mTBI are generally consistent over time; however, inconsistency in retrospective self-reporting of mTBI status is associated with current post-traumatic stress symptoms and non-specific physical health complaints.


Asunto(s)
Lesiones Encefálicas/epidemiología , Lesiones Encefálicas/psicología , Guerra de Irak 2003-2011 , Personal Militar/psicología , Autoinforme , Trastornos por Estrés Postraumático/psicología , Adulto , Lesiones Encefálicas/complicaciones , Negación en Psicología , Femenino , Estado de Salud , Humanos , Estudios Longitudinales , Masculino , Reproducibilidad de los Resultados , Trastornos por Estrés Postraumático/complicaciones , Estados Unidos/epidemiología , Adulto Joven
5.
Langmuir ; 31(22): 6099-106, 2015 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-26001158

RESUMEN

A technique is described for resolving and interpreting molecular interactions with a chemically heterogeneous surface. Using total internal reflection fluorescence microscopy, dynamic single molecule trajectories were accumulated simultaneously for fluorescently labeled fatty acid (interacting primarily via hydrophobic interactions) and dextran (interacting via hydrogen-bonding interactions) probe molecules at the interface between an aqueous solvent and a photopatterned solid surface with distinct regions of amine-terminated and poly(ethylene glycol) self-assembled monolayers. Using dynamic properties of the probe molecules (adsorption rate, surface diffusion coefficient, residence time), an unsupervised Gaussian mixture model algorithm was used to identify areas of the surface that were chemically related to each other, and the dynamic behaviors of the probe molecules were studied statistically on these distinct regions. The dynamic data were compared to data from homogeneous surfaces of known chemistry to provide a chemical identification of each location on the surface. Spatial maps were also constructed, allowing for spatial visualization of surface chemistry on a hydrophilic substrate. This work enables the direct study of interactions between single-molecule probes and distinct surface chemistries, even in the presence of spatial heterogeneity, without human bias, assumptions about surface structure, or model-dependent analysis.


Asunto(s)
Simulación de Dinámica Molecular , Algoritmos , Aminas/química , Dextranos/química , Ácidos Grasos/química , Polietilenglicoles/química , Propiedades de Superficie
6.
Soft Matter ; 11(39): 7712-6, 2015 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-26313353

RESUMEN

Single molecule tracking was used to observe intermittent and anisotropic molecular motion at the solid-nematic interface. Although the interfacial diffusion was dramatically slower than self-diffusion in the nematic, the diffusion anisotropy was the same at the interface and in bulk, supporting the desorption-mediated mechanism of interfacial diffusion, where molecules sample the physical properties of the vicinal fluid phase during flights, and the magnitude of the interfacial diffusion coefficient is primarily determined by the distribution of waiting times between flights.


Asunto(s)
Cristales Líquidos/química , Compuestos de Bifenilo/química , Difusión , Recuperación de Fluorescencia tras Fotoblanqueo , Espectroscopía de Resonancia Magnética , Microscopía Fluorescente , Nitrilos/química
7.
Arch Phys Med Rehabil ; 94(7): 1398-420, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23348125

RESUMEN

OBJECTIVE: To determine the effectiveness and comparative effectiveness of multidisciplinary rehabilitation programs for moderate to severe traumatic brain injury (TBI) in improving participation-related outcomes in adults. This article presents results of select key questions from a recent Agency for Healthcare Quality and Research comparative effectiveness review. DATA SOURCES: MEDLINE, Cochrane Central Register of Controlled Trials, and PsycINFO; hand searches of previous relevant reviews. STUDY SELECTION: We included prospective controlled studies that evaluated the effectiveness or comparative effectiveness of multidisciplinary rehabilitation programs delivered to adults with moderate to severe TBI on their participation in life and community. DATA EXTRACTION: We extracted data, assessed risk of bias, and evaluated strength of evidence. Participation was selected as our primary outcome and included measures of productivity (eg, return to employment or military service) and select scales measuring community integration. Only data from studies with a low or moderate risk of bias were synthesized. DATA SYNTHESIS: Twelve studies met our inclusion criteria; of these, 8 were of low or moderate risk of bias (4 randomized controlled trials of 680 patients and 4 cohort studies of 190 patients, sample size 36-366). Heterogeneous populations, interventions, and outcomes precluded pooled analysis. Evidence was insufficient to draw conclusions about effectiveness. Evidence on comparative effectiveness often demonstrated that improvements were not different between groups; however, this evidence was low strength and may have limited generalizability. CONCLUSIONS: Our review used a rigorous systematic review methodology and focused on participation after multidisciplinary rehabilitation programs for impairments from moderate to severe TBI. The available evidence did not demonstrate the superiority of one approach over another. This conclusion is consistent with previous reviews that examined other patient-centered outcomes. While these findings will have little clinical impact, they do point out the limited evidence available to assess effectiveness and comparative effectiveness while highlighting important issues to consider in future comparative effectiveness research on this topic.


Asunto(s)
Lesiones Encefálicas/rehabilitación , Rehabilitación/métodos , Ensayos Clínicos como Asunto , Investigación sobre la Eficacia Comparativa , Eficiencia , Humanos , Relaciones Interpersonales , Evaluación de Resultado en la Atención de Salud , Índices de Gravedad del Trauma
8.
Behav Sci Law ; 31(6): 814-32, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24105940

RESUMEN

Traumatic brain injury (TBI) is a prominent public health problem in both civilian and military settings. This article discusses similarities and differences in the assessment and treatment of TBI and the attendant forensic implications. Acute care and management of moderate/severe TBI tend to be similar across environments, as is the recognition of disability status in affected individuals. By contrast, an increased focus on mild TBI in recent years has resulted in a reliance on self-report and screening measures to validate the occurrence of events leading to injury. This has complicated assessment, treatment and subsequent medicolegal proceedings. The neuropsychological literature has provided significant guidance on these difficult issues, although the complexity of disability adjudication for active duty members of the military and veterans continues to pose challenges for clinicians in evaluative and treatment contexts.


Asunto(s)
Lesiones Encefálicas/diagnóstico , Personal Militar , Lesiones Encefálicas/rehabilitación , Medicina Legal , Humanos , Neuropsicología/legislación & jurisprudencia , Salud Pública , Índices de Gravedad del Trauma , Resultado del Tratamiento
9.
Clin Neuropsychol ; 37(2): 231-285, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35582913

RESUMEN

OBJECTIVE: Examination of gender and diversity issues within clinical neuropsychology, using data from the 2020 professional practice and "salary survey." METHODS: Clinical neuropsychologists in the U.S. and Canada were invited to participate in an online survey. The final sample consisted of 1677 doctoral-level practitioners. RESULTS: Approximately, 60% of responding neuropsychologists are women and 53.8% of those women identify as early career psychologists (ECPs). Conversely, a majority of men in the sample are advanced career psychologists (ACPs). Both genders work predominantly in institutions, but more men than women work in private practice. ACP men produce a greater number of peer-reviewed publications and conference presentations. Across all work settings, women earn significantly less than men, and are less satisfied with their incomes. Establishing and maintaining family life is the biggest obstacle to attaining greater income and job satisfaction for both genders. Ethnic/racial minority status was identified in 12.9% of respondents, with 59.2% being ECPs. Job satisfaction and hostility in the workplace vary across ethnic/racial minority groups. Hispanic/Latino(a) and White neuropsychologists report higher incomes, but there were no statistically significant differences between any of the groups. CONCLUSIONS: Income and select practice differences persist between female and male neuropsychologists. There is a slow rate of increased ethnic/racial diversity over time, which is much more apparent among early career practitioners. Trajectories and demographics suggest that the gender income gap is unlikely to be improved by the next survey iteration in 2025, whereas it is very likely that ethnic/racial diversity will continue to increase gradually.


Asunto(s)
Neuropsicología , Salarios y Beneficios , Humanos , Femenino , Masculino , Pruebas Neuropsicológicas , Encuestas y Cuestionarios , Renta
10.
Clin Neuropsychol ; 37(1): 141-156, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34779345

RESUMEN

OBJECTIVE: Memory complaints are the most common form of cognitive limitation reported by military service members, but prior research suggests that posttraumatic stress symptoms (PTSS) may account for the link between subjective cognitive complaints and objective cognitive performance. The mechanisms underlying this relationship are largely unknown, including whether the finding applies to memory complaints and performance, which clinical dimensions are involved, and how the association varies when memory complaints are non-credible. METHOD: Using a sample of 196 US military service members, the present study aims to address these gaps by modeling the relationship between objective memory performance and plausible/implausible subjective memory complaints, then evaluating how the association is influenced by PTSS and clinical traits commonly found within PTSS (e.g. depression, anxiety, and somatic concerns). RESULTS: Overall memory complaints were associated with immediate and delayed recall, but both associations were fully mediated by PTSS (95% CI -0.14, -0.01; 95% CI -0.14, -0.02, respectively). Implausible memory complaints, however, were inconsistently linked to memory performance, and no PTSS mediation was observed. Of the clinical traits, only depression moderated the impact of PTSS, specifically by influencing the link between PTSS and overall memory complaints (ß = -0.02, SE = 0.004, p < .001). CONCLUSIONS: These results corroborate the importance of assessment for PTSS and depression in service members who report subjective memory complaints and highlight how targeted intervention for these conditions may play a key role in the management of memory complaints.


Asunto(s)
Trastornos por Estrés Postraumático , Humanos , Trastornos por Estrés Postraumático/psicología , Pruebas Neuropsicológicas , Ansiedad/psicología , Trastornos de Ansiedad
11.
J Clin Med ; 13(1)2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38202021

RESUMEN

Sarcoidosis is a systemic disease with heterogenous clinical phenotypes characterized by non-necrotizing granuloma formation in affected organs. Most disease either remits spontaneously or responds to corticosteroids and second-line disease-modifying therapies. These medications are associated with numerous toxicities that can significantly impact patient quality-of-life and often limit their long-term use. Additionally, a minority of patients experience chronic, progressive disease that proves refractory to standard treatments. To date, there are limited data to guide the selection of alternative third-line medications for these patients. This review will outline the pathobiological rationale behind current and emerging therapeutic agents for refractory or drug-intolerant sarcoidosis and summarize the existing clinical evidence in support of their use.

12.
Clin Neuropsychol ; 37(3): 459-474, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35658794

RESUMEN

Objective:This review provides a summary of historical details and current practice activities related to Forensic Neuropsychology (FN). Under the auspices of the American Board of Clinical Neuropsychology (ABCN), the Forensic Neuropsychology Special Interest Group (FNSIG) views the FN as a subspecialty, which has developed over time as the straightforward result of more than 20 years of numerous publications, extensive continuing education, focused research and growth of forensic practice within neuropsychology. In this article, the FNSIG core work group documents and integrates information that is the basis of efforts to consolidate practice knowledge and facilitate attainment of forensic practice competencies by clinical neuropsychologists. Method:Overview of continuing education topics at professional conferences, search results that identify relevant books and peer-reviewed publications, as well as pertinent findings across years of large-scale national survey results. Results:Relevant evidence has shown for decades that FN is prominent within Clinical Neuropsychology as practiced in the United States and Canada. A majority of U.S. neuropsychologists have received FN training and provide forensic evaluation services. FN practice time per week is considerable for many practitioners, and across survey epochs has been shown to be increasing. Conclusion:The present review leads to the conclusion that in the interest of promoting the acquisition of competence, FN practice should remain a focal point of training and continuing education. Alternate routes to attain competence are discussed, as are ongoing professional activities that undoubtedly will ensure continued growth of, and interest in, the subspecialty of FN.


Asunto(s)
Neuropsicología , Humanos , Estados Unidos , Neuropsicología/educación , Pruebas Neuropsicológicas , Encuestas y Cuestionarios , Canadá
13.
Langmuir ; 28(33): 12108-13, 2012 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-22876990

RESUMEN

The interactions between adsorbate molecules and hydrophobic surfaces are of significant interest due to their importance in a variety of biological and separation processes. However, it is challenging to extrapolate macroscopic ensemble-averaged force measurements to molecular-level phenomena. Using total internal reflection fluorescence microscopy to image individual molecules at hydrophobic solid-aqueous interfaces, we directly observed dynamic behavior associated with the interactions between fluorescently labeled dodecanoic acid (our probe molecules) and self-assembled monolayers (SAM) comprising n-alkyltriethoxysilanes with systematically increasing chain length (from n = 4-18). In all cases, we observed at least two characteristic surface residence times and two diffusive modes, suggesting the presence of multiple distinct adsorbed populations. In general, the mean surface residence time increased and the mobility decreased with increasing SAM chain length, consistent with stronger probe-surface interactions. However, these trends were not primarily due to changes in characteristic residence times or diffusion coefficients associated with the individual populations but rather to a dramatic increase in the fraction associated with the long-lived slow-moving population(s) on long-chain SAMs. In particular, on longer (16-18 carbon) alkylsilane monolayers, the probe molecule exhibited far fewer desorption-mediated "flights" than on short (4-6 carbon) monolayers. Additionally, probes on the longer chain surfaces were much more likely to exhibit extended surface residence times as opposed to short transient surface visits.


Asunto(s)
Interacciones Hidrofóbicas e Hidrofílicas , Ácidos Láuricos/química , Simulación de Dinámica Molecular , Silanos/química , Alcanos/química , Difusión , Colorantes Fluorescentes/química , Propiedades de Superficie , Agua/química
14.
J Int Neuropsychol Soc ; 18(5): 845-55, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22687547

RESUMEN

This study explored whether remote blast-related MTBI and/or current Axis I psychopathology contribute to neuropsychological outcomes among OEF/OIF veterans with varied combat histories. OEF/OIF veterans underwent structured interviews to evaluate history of blast-related MTBI and psychopathology and were assigned to MTBI (n = 18), Axis I (n = 24), Co-morbid MTBI/Axis I (n = 34), or post-deployment control (n = 28) groups. A main effect for Axis I diagnosis on overall neuropsychological performance was identified (F(3,100) = 4.81; p = .004), with large effect sizes noted for the Axis I only (d = .98) and Co-morbid MTBI/Axis I (d = .95) groups relative to the control group. The latter groups demonstrated primary limitations on measures of learning/memory and processing speed. The MTBI only group demonstrated performances that were not significantly different from the remaining three groups. These findings suggest that a remote history of blast-related MTBI does not contribute to objective cognitive impairment in the late stage of injury. Impairments, when present, are subtle and most likely attributable to PTSD and other psychological conditions. Implications for clinical neuropsychologists and future research are discussed. (JINS, 2012, 18, 1-11).


Asunto(s)
Trastorno de Personalidad Antisocial/complicaciones , Trastorno de Personalidad Antisocial/etiología , Traumatismos por Explosión/complicaciones , Conmoción Encefálica/complicaciones , Conmoción Encefálica/etiología , Trastornos del Conocimiento/etiología , Adulto , Campaña Afgana 2001- , Trastornos del Conocimiento/diagnóstico , Estudios de Cohortes , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Estudios Retrospectivos , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/etiología , Índices de Gravedad del Trauma , Estados Unidos/epidemiología , Veteranos/psicología , Adulto Joven
15.
Clin Psychol Sci ; 10(3): 499-513, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-38020495

RESUMEN

Among individuals with posttraumatic stress disorder (PTSD), verbal learning and memory are areas of weakness compared with other cognitive domains (e.g., visuospatial memory). In this study, previously deployed military veterans completed clinical assessments of word memory and vocabulary (n = 243) and a laboratory task measuring encoding, free recall, repetition priming, and recognition of words (n = 147). Impaired verbal memory was selectively related to reexperiencing symptoms of PTSD but was not associated with other symptom groupings or blast-induced traumatic brain injury. Implicit priming of response times following word repetition was also unrelated to clinical symptoms. Instead, slowed response times during encoding explained associations between reexperiencing and memory performance. These findings are consistent with alterations in attentional control explaining PTSD-related verbal-memory deficits. Such findings have implications for understanding trauma-focused psychotherapy and recovery, which may depend on efficient attentional processing of words to alter posttraumatic reexperiencing symptoms.

16.
Phys Rev Lett ; 107(15): 156102, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-22107306

RESUMEN

By directly observing molecular trajectories on a chemically heterogeneous surface, we have identified two distinct modes of diffusion involving (1) displacements within isolated surface islands (crawling mode), and (2) displacements where a molecule desorbs from an island, diffuses through the adjacent liquid phase, and readsorbs on another island (flying mode). The diffusion coefficients corresponding to these two modes differ by an order of magnitude, and both modes are also observed on chemically homogeneous surfaces. Comparison with previous results suggested that desorption-mediated diffusion is the primary transport mechanism in self-assembled monolayer formation.

17.
Brain Inj ; 25(5): 511-25, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21405948

RESUMEN

BACKGROUND/OBJECTIVE: Soldiers of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF) sustain blast-related mild traumatic brain injury (concussion) with alarming regularity. This study discusses factors in addition to concussion, such as co-morbid psychological difficulty (e.g. post-traumatic stress) and symptom validity concerns that may complicate neuropsychological evaluation in the late stage of concussive injury. CASE REPORT: The study presents the complexities that accompany neuropsychological evaluation of blast concussion through discussion of three case reports of OEF/OIF personnel. DISCUSSION: The authors emphasize uniform assessment of blast concussion, the importance of determining concussion severity according to acute-injury characteristics and elaborate upon non-concussion-related factors that may impact course of cognitive limitation. The authors conclude with a discussion of the need for future research examining the impact of blast concussion (particularly recurrent concussion) and neuropsychological performance.


Asunto(s)
Traumatismos por Explosión/complicaciones , Conmoción Encefálica/psicología , Pruebas Neuropsicológicas/normas , Trastornos por Estrés Postraumático/psicología , Veteranos/psicología , Adulto , Campaña Afgana 2001- , Traumatismos por Explosión/psicología , Conmoción Encefálica/etiología , Humanos , Guerra de Irak 2003-2011 , Masculino , Trastornos por Estrés Postraumático/diagnóstico
18.
J Alzheimers Dis Rep ; 5(1): 601-611, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34514342

RESUMEN

BACKGROUND: Utilities of blood-based biomarkers in Alzheimer's disease (AD) clinical trials remain unknown. OBJECTIVE: To evaluate the ability of plasma neurofilament light chain (NfL) to predict future declines in cognition and activities of daily living (ADL) outcomes in 26 older adults with mild-to-moderate AD dementia from the FIT-AD Trial. METHODS: Plasma NfL was measured at baseline and 3 and 6 months. Cognition and ADL were assessed using the AD Assessment Scale-Cognition (ADAS-Cog) and AD Uniform Dataset Instruments and Disability Assessment for Dementia (DAD), respectively, at baseline, 3, 6, 9, and 12 months. Linear mixed effects models were used to examine the associations between baseline or change in plasma NfL and changes in outcomes. RESULTS: Higher baseline plasma NfL was associated with greater rate of decline in ADAS-Cog from baseline to 6 months (standardized estimate of 0.00462, p = 0.02853) and in ADL from baseline to 12 months (standardized estimate of -0.00284, p = 0.03338). Greater increase in plasma NfL in short term from baseline to 3 months was associated with greater rate of decline in memory and ADL from 3 to 6 months (standardized estimate of -0.04638 [0.003], p = 0.01635; standardized estimate of -0.03818, p = 0.0435) and greater rate of decline in ADL from 3 to 12 month (standardized estimate of -0.01492, p = 0.01082). CONCLUSION: This study demonstrated that plasma NfL might have the potential to predict cognitive and function decline up to 12 months. However, future studies with bigger sample sizes need to confirm the findings.

19.
Clin Neuropsychol ; 35(7): 1205-1231, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34096460

RESUMEN

Objective: The current study summarizes the results of a 2020 survey that solicited information regarding backgrounds, beliefs, practices, and incomes of clinical neuropsychologists who practice in Canada. Methods: Clinical neuropsychologists who practice in Canada were invited to participate in an online survey that was available from 1/17/20 to 4/02/20. Available survey findings were obtained from 111 respondents, which reflects a response rate of 51.3% of the 216 doctoral-level Canadian neuropsychologists identified in at least one major North American or international professional organization membership list (AACN, INS, NAN, or SCN). Results: Most of the current respondents were White/Caucasian women who identified as adult providers and worked full-time in urban institutional settings. Four Canadian provinces (Alberta, British Columbia, Ontario, Quebec) accounted for more than 91% of the current respondent sample. Incomes and career satisfactions were largely encouraging, though some important variations were noted by province, work setting, and professional identity. Incomes were significantly associated with forensic practices and years of clinical experience. Most respondents made use of technician support in their practices, largely to increase productivity and patient volume. Only a small minority of respondents were board-certified and there was generally limited interest in future board certification. Conclusions: While important similarities were observed in the current Canadian sample relative to recent survey findings obtained in a U.S. sample, results also reveal a number of important differences that serve as important areas of future consideration.


Asunto(s)
Neuropsicología , Salarios y Beneficios , Adulto , Canadá , Femenino , Humanos , Pruebas Neuropsicológicas , Práctica Profesional , Encuestas y Cuestionarios
20.
Clin Neuropsychol ; 35(1): 7-80, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33375892

RESUMEN

OBJECTIVE: This portion of the 2020 survey updates practice information, beliefs, and income data of clinical neuropsychologists who practice within the United States. Methods: Doctoral-level neuropsychology practitioners were invited via numerous methods, with multiple reminders, to participate in a web-based survey from January 17 through April 2, 2020. The useable U.S. sample of 1677 doctoral-level practitioners was 6.2% larger than the comparable group in the prior 2015 practice survey. Results: Whereas women practitioners predominate, which continues a steeply increasing trend across time, increases in overall ethnic/racial diversity continue at a slow pace. Median age has remained very similar over the last 30 years, reflecting a continuous influx of young practitioners. A relatively small minority of neuropsychologists work part time. The proportion of board-certified neuropsychologists continues to show meaningful increase; interest in subspecialization certification is relatively high. Reliance on technicians remains popular, especially for neuropsychologists who work in institutions or are board certified. Although implementation of new CPT codes in 2019 and related payor policies appear to have had more negative than positive effects, psychology-related annual incomes of neuropsychologists have again increased compared to prior surveys. Variables such as specific work setting, state, region, years in practice, forensic practice hours, board certification, and basis for determining income (e.g. hours billed, revenue collected, relative value units) have an impact on income. More than half of practitioners engage in forensic neuropsychology, with the number of related practice hours per week again increasing. There is very high agreement regarding the use of response validity measures in clinical practice and forensic practice. Neurologists remain the number one referral source whether working in an institution, private practice, or a combination of both, and regardless of maintaining a pediatric, adult, or lifespan practice. Career satisfaction ratings for income, job, and work-life balance remain high, with the majority of ratings regarding the future of the specialty in the positive range. Additional data summaries related to a wide range of professional and practice topics are provided. Conclusions: Updating and comparing survey information at five-year intervals continues to provide insights and perspectives regarding relative stabilities and changes in practice activities, beliefs, and incomes of U.S. clinical neuropsychologists. Such information also provides guidance regarding the future of the specialty.


Asunto(s)
Actitud del Personal de Salud , Renta/estadística & datos numéricos , Neuropsicología/economía , Práctica Profesional/economía , Salarios y Beneficios/economía , Adulto , Empleo/economía , Femenino , Humanos , Masculino , Neuropsicología/estadística & datos numéricos , Práctica Profesional/estadística & datos numéricos , Salarios y Beneficios/estadística & datos numéricos , Encuestas y Cuestionarios , Estados Unidos , Lugar de Trabajo
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