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1.
Sci Educ (Arlingt) ; 29(1): 1-11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098957

RESUMO

With few resources and little time for professional development, science education leaders need ways to efficiently disseminate effective pedagogical practices, improve instruction, and support science teachers (Shaked and Schecter, 2016). Efficient leader strategies are especially important as teachers and districts face reforms to existing standards. One potential avenue for dissemination is leveraging the informal social networks of teachers. Therefore, it is necessary to map and interpret informal teacher networks. We describe a case study involving a partnership of university researchers and a district science curriculum specialist who collected survey data to map district teacher informal advice-seeking networks. We also describe the kinds of network analysis information that science education leaders can use to make strategic decisions about the costs and benefits of efforts directed at all teachers (e.g. workshops, annual professional development time) and those directed at highly connected teachers who can become or already are informal leaders in their communities.

2.
Q J Exp Psychol (Hove) ; : 17470218231203459, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37706292

RESUMO

Music listening affects time perception, with previous studies suggesting that a variety of factors may influence this: musical, individual, and environmental. Two experiments investigated the effect of musical factors (tonality and musical tempo) and individual factors (a listener's level of musical sophistication) on subjective estimates of duration. Participants estimated the duration of different versions of newly composed instrumental music stimuli under retrospective and prospective conditions. Stimuli varied in tempo (90-120 bpm) and tonality (tonal-atonal), in a 2 × 2 factorial design, while other musical parameters remained constant. Estimates were made using written estimates of minutes and seconds in Experiment 1, and the reproduction method in Experiment 2. Two-way analyses of variance (ANOVAs) showed no main effect of tonality on estimates and no significant interactions between tempo and tonality, under any condition. Musical tempo significantly affected estimates, with the faster tempo leading to longer estimates, but only in the prospective condition, and with the use of the reproduction method. Correlation matrices using the Pearson correlation coefficient found no correlation between musical sophistication scores (measured using the Goldsmiths Musical Sophistication Index [Gold-MSI]) and verbal or reproduction estimates. In conclusion, together with the existing literature, findings suggest that (1) changes in tonality, without further changes in rhythm, metre, or melodic contour, do not significantly affect estimates; (2) small changes in musical tempo influence only prospective reproduction estimates, with larger tempo differences or longer stimuli being needed to cause changes in retrospective estimates; (3) participants' level of musical sophistication does not impact estimates of musical duration; and (4) empirical research on music listening and subjective time must consider potential method-dependent results.

3.
Environ Sci Pollut Res Int ; 30(47): 104477-104488, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37702867

RESUMO

China's Paris Agreement Pledge and recent introduction of an Emissions Trading Scheme have created a need for information on where it makes the most economic sense to use different sources of energy. With lower carbon dioxide emissions, natural gas and liquefied petroleum gas provide cleaner sources of energy relative to coal. Although it is practically crucial to investigate the use of these two sources, empirical studies are limited due to lack of data. To fill the research gap, this paper studies the efficiency of natural gas and liquefied petroleum gas sector in China by using data from 24 major province-level divisions over the years 2006-2015. Efficiency is defined as the utility's ability to produce the highest output given fixed inputs. We find that: (1) GDP per capita and high customer density are associated with higher levels of efficiency and (2) utilities that serve higher proportions of households (as opposed to industry and firms) are associated with lower levels of efficiency. Policy makers can use this information to address China's energy needs due to rapid urbanization while also pursuing Paris Agreement goals.


Assuntos
Gás Natural , Petróleo , Carvão Mineral , Urbanização , China , Desenvolvimento Econômico , Dióxido de Carbono/análise
4.
Nurse Educ Today ; 121: 105659, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36470041

RESUMO

OBJECTIVES: To clarify capability for work readiness in newly graduated registered nurses as viewed from the perspective of clinicians in practice, educators in tertiary institutions, and graduates. DESIGN: Integrative review. DATA SOURCES: Databases searched for peer-reviewed studies included PubMed, MEDLINE, ERIC, Campbell collaboration, Google Scholar, and Cochrane databases. REVIEW METHODS: Pragmatism informed this integrative review. The five-stage method described by Whittemore and Knafl was used to enable rigorous examination of the expected capability of graduate nurses. A comprehensive database search was conducted using PRISMA guidelines. Eighteen articles were appraised and analysed for this review. The capability concept was used as a framework for analysis. RESULTS: Eighteen articles met the inclusion criteria. Findings revealed that although there is no definition for graduate nurses' work readiness, there is a common theme. Graduate nurses are expected to have broad theoretical knowledge (knowing) along with practical knowledge (doing). They are also expected to demonstrate integrity, honesty, respect, compassion, and a moral compass. A list of personal attributes and organisational acumen was also reflective of graduate readiness upon entering the workforce and identified as necessary capabilities for graduates. CONCLUSIONS: A picture of the perfect employee is illustrated in the definition of work readiness by the participants of the original studies. Yet there is a lack of stakeholder consensus on the capabilities expected from a graduate nurse.


Assuntos
Educação de Pós-Graduação em Enfermagem , Enfermeiras e Enfermeiros , Humanos , Recursos Humanos
5.
Front Rehabil Sci ; 3: 873216, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188900

RESUMO

From a humanistic perspective, participatory processes in research find support on both ethical and moral grounds. In practical terms however, it is often difficult to establish protocols that best honour (i.e., elicit, capture, and integrate) the opinions of individuals and groups that represent the various specific stakeholders (e.g., from allied health, scientific, and academic disciplines) needed to investigate complex phenomena. Here, we describe a consultation process (funded by Parkinson's UK) devised to explore use of music among people with Parkinson's in relation to potential applications to enhance quality of life. People with Parkinson's were paired with researchers in order to discuss music on an equal footing so as to enable participant empowerment. We describe outcomes that demonstrate avenues of success as a result of this approach and additional insights gained through these processes in the hope of informing future practise. It has been our experience that researchers must establish a balance between (a) ensuring methodological rigour within an appropriate framework, and (b) facilitating informal "playtime" that develops connectivity between participants and enables both creative thinking and reflexive practise amongst stakeholders. We encourage researchers not to underestimate "playtime" as an important vehicle to foster this social interactivity and fuel the good will required to conduct inclusive and relevant research.

6.
Sci Total Environ ; 824: 153802, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35150681

RESUMO

Aboveground net primary productivity (ANPP) of an ecosystem is among the most important metrics of valued ecosystem services. Measuring the efficiency scores of ecological production (ESEP) based on ANPP using relevant variables is valuable for identifying inefficient sites. The efficiency scores computed by the Data Envelopment Analysis (DEA) may be influenced by the number of input variables incorporated into the models and two DEA settings-orientations and returns-to-scales (RTSs). Therefore, the objectives were threefold to: (1) identify soil-environmental variables relevant to ANPP, (2) assess the sensitivity of ESEP to the number of input variables and DEA settings, and (3) assess local management relations with ESEP. The ANPP rates were calculated for pine forests in the southeastern U.S. where 10 management types were used. This was followed by an all-relevant variable selection technique based on 696 variables that cover biotic, pedogenic, climatic, geological, and topographical factors. Five minimal-optimal variable selection techniques were further applied to create five parsimonious sets that contain a different number of variables used as DEA inputs. After setting ANPP as the output variable, two DEA orientations (input/output) and six RTS were applied to compute ESEP. The variable selection methods succeeded in objectively identifying the major factors relevant to ANPP variation. The site index showed the highest correlation with ANPP (r = 0.39), while various precipitation factors were negatively correlated (r = - 0.15~ - 0.29, p < 0.01). Parsimonious ESEP models observed a decrease in score variances as the number of input variables increased. Various RTS produced similar scores across orientations. Of the DEA settings, an output orientation with decreasing RTS produced the most progressive ESEP with large variation. Results also suggested that macro- and micronutrient fertilization is the best combination of management strategies to achieve high ESEP. This holistic benchmark approach can be applied to other ecological functions in diverse regions.


Assuntos
Ecossistema , Solo , Florestas , Sudeste dos Estados Unidos
7.
Int J STEM Educ ; 9(1): 10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35106273

RESUMO

BACKGROUND: Designed in 2012 with a first implementation in 2013, NE STEM 4U is a professional development program for post-secondary students/undergraduates, and serves as a source of outreach, content knowledge generation, and STEM literacy for youth in grades kindergarten through 8th grade (ages 5-14). The model empowers post-secondary students as facilitators of inquiry-based learning within the context of an out-of-school time program. This study investigated the potential for replicating or 'franchising' this model by evaluating on the following: (1) Is the model replicable? And, if so, (2) what core elements are necessary for program fidelity? And (3) is there a dependency on a particular setting/participant type (e.g., a more rural or urban setting)? RESULTS: Strategic expansion of the program to different institutional types (i.e., Research 1, Research II, and a predominantly undergraduate institution), different geographical locations (i.e., rural and urban), and with various school district partners (i.e., large and small) determined that program fidelity and replicability required 4 core elements or criteria: (i) intentional programming, (ii) staff quality, (iii) effective partnerships, and (iv) program evaluation and continuous improvement. Importantly, we examined emergent themes by each site, as well as in combination (n = 16 focus group participants, n = 12 reflection surveys). These data indicated that Flexibility (21.22%), Student Engagement (i.e., Youth) (19.53%), Classroom Management (i.e., also pertaining to youth) (19.31%), and Communication (15.71%) were the themes most referenced by the post-secondary student mentors in the NE STEM 4U program, regardless of site. Finally, the YPQA results demonstrate general replication of program quality in a "franchise" location. CONCLUSIONS: These results highlight the core elements of the NE STEM 4U program for consideration of expansion (through strategic replication or 'franchising') as a possible international model. The findings and voices highlight the program's trajectory toward success into environments that expand professional development for post-secondary students, and for delivering STEM opportunities for youth. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40594-021-00320-0.

8.
Front Psychol ; 11: 1001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547450

RESUMO

BACKGROUND: This study concerns the perception of musical segmentation during listening to live contemporary classical music. Little is known about how listeners form judgments of musical segments, particularly when typical section markers, such as cadences and fermatas, are absent [e.g., Sears et al. (2014)] or when the music is non-tonal (e.g., in much contemporary classical music). AIMS: The current study aimed to examine the listeners' segmentation decisions in a piece of contemporary music, Ligeti's "Fanfares"? METHODS: Data were gathered using a smartphone application [Practice & Research in Science & Music (PRiSM) Perception App] designed for this study by the Royal Northern College of Music (RNCM) Centre for PRiSM and the Oxford e-Research Centre. A total of 259 audience participants were asked to "tap" when they felt that a section had ended. Subjective responses were captured, as well as contextual data about the participants. RESULTS: The audience members demonstrated high levels of agreement regarding segmentation, mostly at places in the music involving breaks in the musical texture (one piano hand resting), changes in dynamic (volume), and changes in register/pitch. A sense of familiarity with contemporary repertoire did seem to influence the responses-the participants who self-reported being familiar with contemporary music used a wider range of cues to make their segmentation decisions. The self-report data analysis suggested that the listeners were not always aware of how they made decisions regarding segmentation. The factors which may influence their judgment of musical segmentation are, to some extent, similar to those identified by music analysis (Steinitz, 2011) but different in other ways. The effect of musical training was found to be quite small. CONCLUSION: Whether musically trained and/or familiar with contemporary classical music or not, the listeners demonstrate commonalities in segmentation, which they are not always aware of. This study has implications for contemporary composers, performers, and audiences and how they engage with new music in particular.

9.
J Oncol Pharm Pract ; 25(8): 1839-1845, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30551722

RESUMO

BACKGROUND: Capecitabine is an oral chemotherapeutic agent used in colorectal cancer. Two prior studies found a negative impact with the concomitant use of proton pump inhibitor agents during treatment with capecitabine in patients with early colorectal and gastroesophageal cancers. OBJECTIVE: To determine if there is a clinical impact of the concomitant use of capecitabine and acid suppression therapy in patients with local and metastatic colorectal cancer. METHODS: This was a single-center retrospective cohort study of adult patients with colorectal cancer on capecitabine monotherapy between 2011 and 2017. Progression-free survival (PFS) and overall survival were compared between patients on acid suppression therapy and those not on acid suppression therapy. RESULTS: A total of 70 patients were included. Patients on acid suppression therapy at capecitabine initiation (21%) had decreased progression-free survival versus those not on acid suppression therapy (HR 2.24, 95% CI 1.06-4.41, p = 0.035), after adjusting for disease severity and age. Acid suppression therapy use was associated with a numerical decrease in overall survival (HR 1.86, 95% CI 0.81-3.91, p = 0.14). In patients on any concomitant acid suppression therapy (25%), there was a decreased rate of progression-free survival (HR 6.21, 95% CI 2.56-14.32, p = 0.0001) but not overall survival (HR 1.64, 95% CI 0.68-3.54, p = 0.25) versus those without concomitant acid suppression therapy, after adjusting for age and disease severity. CONCLUSIONS: Concurrent use of acid suppression therapy and capecitabine was associated with decreased progression-free survival, and there was a trend towards decreased overall survival. Due to the demonstrated potential of decreased efficacy, concurrent use of proton pump inhibitors or histamine 2 receptor antagonists should be avoided in colorectal cancer patients on treatment with capecitabine monotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Capecitabina/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Inibidores da Bomba de Prótons/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Intervalo Livre de Doença , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
10.
J Neurooncol ; 139(3): 617-623, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29774497

RESUMO

INTRODUCTION: Patients with intracranial masses are often advised to avoid airflight due to concerns of worsening neurological symptoms or deterioration. However, many patients often travel cross-country or internationally to tertiary care centers for definitive care. This study assesses the safety of commercial airflight for brain and skull base tumor patients without severe or progressive neurological deficits. METHODS: Patients that had traveled to our institution for surgery via commercial airflight from 2014 to 2017 were identified. An electronic survey was administered (RedCap) and flight duration, aircraft type, presenting symptoms and new or worsened peri-flight symptoms were queried. Severity was assessed using visual analogue scale (VAS). Significant change of symptoms was determined to be greater than 25%. Demographics and clinical history were obtained from electronic medical records. Providence Health System IRB: 16-168. RESULTS: Of 665 patients operated on for brain tumor, 63 (9.5%) traveled by airflight to our center for surgery and of these, 41 (65%) completed the study (mean age 48.5 ± 16.8 years, 63% female). Pathology included pituitary and other parasellar tumors (58%), meningiomas (22%), metastatic tumors (5%), gliomas (5%), pineal tumor (5%), cerebello-pontine tumor (5%). Average tumor volume was 11.4 cc and average maximal dimension was 2.7 cm. Ten (24.4%) patients developed worsened symptoms during airflight including: headaches 3/19 (15.8%), fatigue 3/14 (21.4%), dizziness 3/5 (60%) and ear pain 3/3 (100%), as well as one patient who had new onset seizures inflight. Seven patients (70%) sustained worsened symptoms after airflight. There were no permanent neurological deficits related to airflight. There was no correlation with tumor size, volume, location or flight duration with development of neurological symptoms. There was an inverse correlation between peri-flight corticosteroid usage and symptom exacerbation (p = 0.048). No patient with completely asymptomatic tumors developed new symptoms during flight. CONCLUSIONS: Most patients with brain and skull base tumors can travel safely via commercial airflight with acceptable symptom exacerbation. However, consideration should be given to administering corticosteroids and possibly anticonvulsants to patients who are symptomatic and/or have relatively large tumors with mass effect and peritumoral edema.


Assuntos
Aeronaves , Neoplasias Encefálicas , Segurança do Paciente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Transporte de Pacientes , Adulto Jovem
11.
J Alzheimers Dis ; 51(1): 263-75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26836171

RESUMO

A substantial body of research evidence is indicative of disproportionately slowed information processing speed in a wide range of multi-trial, computer-based, neuroimaging- and electroencephalography-based reaction time (RT) tests in Alzheimer's disease and mild cognitive impairment (MCI). However, in what is arguably a dichotomy between research evidence and clinical practice, RT associated with different brain functions is rarely assessed as part of their diagnosis. Indeed, often only the time taken to perform a single, specific task, commonly the Trail making test (TMT), is measured. In clinical practice therefore, there can be a failure to assess adequately the integrity of the rapid, serial information processing and response, necessary for efficient, appropriate, and safe interaction with the environment. We examined whether a typical research-based RT task could at least match the TMT in differentiating amnestic MCI (aMCI) from cognitively healthy aging at group level. As aMCI is a heterogeneous group, typically containing only a proportion of individuals for whom aMCI represents the early stages of dementia, we examined the ability of each test to provide intra-group performance variation. The results indicate that as well as significant slowing in performance of the operations involved in TMT part B (but not part A), individuals with aMCI also experience significant slowing in RT compared to controls. The results also suggest that research-typical RT tests may be superior to the TMT in differentiating between cognitively healthy aging and aMCI at group level and in revealing the performance variability one would expect from an etiologically heterogeneous disorder such as aMCI.


Assuntos
Disfunção Cognitiva/fisiopatologia , Processos Mentais/fisiologia , Tempo de Reação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Eletroencefalografia , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Estimulação Luminosa , Características de Residência
12.
Int J Mol Sci ; 16(10): 24600-13, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26501267

RESUMO

Findings from epidemiological and observational studies have indicated that diets high in omega-3 polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may reduce the risk of cognitive decline and Alzheimer's disease (AD). To determine if increasing intake of DHA and EPA through supplementation is beneficial to cognition and mood in individuals with cognitive impairment no dementia (CIND) or Alzheimer's disease (AD) a four month, randomised, double-blind, placebo controlled study was conducted. Fifty-seven participants with CIND and nineteen with AD were randomised to receive either omega-3 PUFAs (600 mg EPA and 625 mg DHA per day) or placebo (olive oil) over a four month period. Elevating depleted levels of EPA and DHA through supplementation in individuals with CIND or AD was found to have negligible beneficial effect on their cognition or mood. These findings confirm an overall negligible benefit of omega-3 PUFA supplementation for those with cognitive impairment and dementia. More intervention studies need to be undertaken with longer study durations and larger sample sizes. It may prove fruitful to examine effects of different doses as well as effects in other dementia subtypes.


Assuntos
Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Suplementos Nutricionais , Ácidos Graxos Ômega-3 , Afeto/efeitos dos fármacos , Idoso , Ácidos Docosa-Hexaenoicos , Método Duplo-Cego , Ácido Eicosapentaenoico , Feminino , Humanos , Masculino
13.
J Contin Educ Nurs ; 46(9): 409-15, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26352044

RESUMO

Making the transition from student to RN is challenging and demanding. In Australia, where nurses commonly graduate after 3 years in a Bachelor of Nursing program, graduate transition programs have been established in the workplace to support and socialize new graduates to nursing practice. These programs vary in content, rigor, and available support mechanisms, and no nationally agreed upon standards of expected graduate performance exist. Providing a structured, evidence-based, and clinically focused education and support program specific to the needs of graduate nurses contributes to quality care and patient safety and has significant benefits for the individual graduate, the employing organizations, and health care. This article presents the development and implementation of the Bachelor of Nursing With Clinical Honors (Transition to Practice) program offered by the University of Tasmania, in collaboration with St. Vincent's Private Hospital, Sydney, Australia.


Assuntos
Bacharelado em Enfermagem/organização & administração , Educação de Pós-Graduação em Enfermagem/organização & administração , Modelos Educacionais , Adaptação Psicológica , Austrália , Escolha da Profissão , Relações Comunidade-Instituição , Currículo , Humanos , Avaliação das Necessidades , Desenvolvimento de Programas , Tasmânia
14.
J Med Toxicol ; 10(2): 205-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24798647

RESUMO

INTRODUCTION: Physostigmine was once a widely used antidote for the treatment of antimuscarinic toxicity. However, reports describing the association of physostigmine with asystole and seizures in severe tricyclic antidepressant poisoning resulted in a decrease in use. Recent literature has demonstrated that physostigmine is a safe and effective antidote for the treatment of antimuscarinic toxicity. There are only two previously published articles regarding the use of physostigmine administered as a continuous intravenous infusion for persistent antimuscarinic toxicity. We present a case of physostigmine continuous infusion for the treatment of antimuscarinic symptoms in a polydrug overdose due to the ingestion of diphenhydramine along with bupropion, citalopram, acetaminophen, and naproxen. CASE PRESENTATION: A 13-year-old female presented with hyperthermia, myoclonus and rigidity, hallucinations, severe agitation, and antimuscarinic toxicity including inability to sweat after a polydrug overdose. Several doses of lorazepam were administered followed by physostigmine which produced resolution of hallucinations and attenuation of the antimuscarinic symptoms including perspiration, temperature improvement, and decreased agitation. After periods of improvement and recurrence of antimuscarinic effects, a continuous infusion of physostigmine was administered at 2 mg/h and continued for almost 8 h to maintain attenuation of symptoms. GABAergic agents including lorazepam and phenobarbital were used later in the hospital course for presumed symptoms of serotonergic and adrenergic toxicity after resolution of antimuscarinic effects. The patient did not experience any adverse effects of physostigmine administration. DISCUSSION: Physostigmine administered as a continuous infusion may be a reasonable treatment option for severe and recurrent symptoms related to antimuscarinic toxicity.


Assuntos
Antídotos/administração & dosagem , Inibidores da Colinesterase/administração & dosagem , Overdose de Drogas/tratamento farmacológico , Antagonistas Muscarínicos/intoxicação , Fisostigmina/administração & dosagem , Tentativa de Suicídio , Adolescente , Antídotos/efeitos adversos , Antídotos/uso terapêutico , Inibidores da Colinesterase/efeitos adversos , Inibidores da Colinesterase/uso terapêutico , Terapia Combinada/efeitos adversos , Overdose de Drogas/fisiopatologia , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Infusões Intravenosas , Antagonistas Muscarínicos/química , Fisostigmina/efeitos adversos , Fisostigmina/uso terapêutico , Polimedicação , Recidiva , Índice de Gravidade de Doença , Resultado do Tratamento
15.
J Alzheimers Dis ; 40(1): 177-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24366922

RESUMO

Although there is some evidence that amnestic mild cognitive impairment (aMCI) can be characterized by significant deficits in visuospatial function, the cross-sectional design of the majority of these studies renders it impossible to determine whether such deficits occur in aMCI as a result of, or accompany, amnestic dysfunction per se or whether they are the result of disproportionately poorer performance in a sub-group of patients for whom aMCI represents prodromal dementia. Similarly, whether the absence of aMCI-related functional deficit stems from the masking of dementia-specific abnormality by the preserved performance of those with a different cause of aMCI cannot be ascertained. Here we report the outcome of a cross-sectional and 2.5-year longitudinal evaluation follow-up, computer-based study of visuospatial attention, specifically attentional disengagement and inhibition of return and the mean (RTSPEED) and intra-individual variability (IIVRT) of their component reaction times, in 45 patients with aMCI and 31 cognitively healthy older adults. Reduced inhibition of return (p = 0.01 and p = 0.037 in response to 400 and 800 ms cue to target interval conditions), slowed RTSPEED (p = 0.038 and p = 0.03 in response to 400 and 800 ms cue), and raised IIVRT at baseline testing (p = 0.003, p = 0.026, p = 0.013 in response to 200, 400 and 800 ms cue) were associated with the development of dementia within the 2.5-year follow-up period, whereas the performance of patients with aMCI who did not develop dementia did not differ significantly from that of the cognitively healthy controls. Attentional disengagement appeared insensitive to the presence of prodromal dementia or amnestic dysfunction per se. The results indicate that those patients for whom aMCI represents prodromal dementia may experience, in addition to amnestic dysfunction, a decline in the functional integrity of some fundamental aspects of visual information processing, an effect potentially capable of increasing disease burden and reducing quality of life.


Assuntos
Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia , Inibição Psicológica , Deficiências da Aprendizagem/etiologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Estudos Retrospectivos
16.
PLoS One ; 8(6): e65712, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762413

RESUMO

Compared to cognitively healthy ageing (CH), intra-individual variability in reaction time (IIV(RT)), a behavioural marker of neurological integrity, is commonly reported to increase in both Alzheimer's disease (AD) and mild cognitive impairment (MCI). It varies in MCI with respect to whether it represents the pro-dromal stages of dementia or not; being greatest in those most likely to convert. Abnormal IIV(RT) in MCI therefore represents a potential measure of underlying functional integrity that may serve to differentiate MCI from CH and to help identify those patients for whom MCI is the result of a progressive pathological process. As the clinical approach to MCI is increasingly stratified with respect to gender, we investigated whether this factor could influence study outcome. The influence of RTSPEED and processing load upon IIV(RT) was also examined. Under low processing load conditions, IIV(RT) was significantly increased in both MCI and AD compared to CH. However, correcting for an individual's processing speed abolished this effect in MCI but not in AD, indicating that the increased IIV(RT) in MCI and AD may result from different factors. In MCI but not in CH, IIV(RT) was significantly greater for females. Increasing task processing load by adding distracting information, although increasing overall IIV(RT), failed to improve the differentiation between CH and both MCI and AD, and in MCI resulted in a reduction in the influence of gender upon study outcome. The outcome of studies investigating IIV(RT) in MCI and AD compared to CH therefore appear influenced by the gender of the participants, by task-related processing load and processing speed.


Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Processos Mentais/fisiologia , Tempo de Reação/fisiologia , Adulto , Idoso , Doença de Alzheimer/psicologia , Estudos de Casos e Controles , Disfunção Cognitiva/psicologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores Sexuais
17.
PLoS One ; 8(5): e62554, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23690943

RESUMO

Adipose-derived stem cells (ASC) are multipotent stem cells that show great potential as a cell source for osteogenic tissue replacements and it is critical to understand the underlying mechanisms of lineage specification. Here we explore the role of primary cilia in human ASC (hASC) differentiation. This study focuses on the chemosensitivity of the primary cilium and the action of its associated proteins: polycystin-1 (PC1), polycystin-2 (PC2) and intraflagellar transport protein-88 (IFT88), in hASC osteogenesis. To elucidate cilia-mediated mechanisms of hASC differentiation, siRNA knockdown of PC1, PC2 and IFT88 was performed to disrupt cilia-associated protein function. Immunostaining of the primary cilium structure indicated phenotypic-dependent changes in cilia morphology. hASC cultured in osteogenic differentiation media yielded cilia of a more elongated conformation than those cultured in expansion media, indicating cilia-sensitivity to the chemical environment and a relationship between the cilium structure and phenotypic determination. Abrogation of PC1, PC2 and IFT88 effected changes in both hASC proliferation and differentiation activity, as measured through proliferative activity, expression of osteogenic gene markers, calcium accretion and endogenous alkaline phosphatase activity. Results indicated that IFT88 may be an early mediator of the hASC differentiation process with its knockdown increasing hASC proliferation and decreasing Runx2, alkaline phosphatase and BMP-2 mRNA expression. PC1 and PC2 knockdown affected later osteogenic gene and end-product expression. PC1 knockdown resulted in downregulation of alkaline phosphatase and osteocalcin gene expression, diminished calcium accretion and reduced alkaline phosphatase enzymatic activity. Taken together our results indicate that the structure of the primary cilium is intimately associated with the process of hASC osteogenic differentiation and that its associated proteins are critical players in this process. Elucidating the dynamic role of the primary cilium and its associated proteins will help advance the application of hASC in generating autologous tissue engineered therapies in critical defect bone injuries.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular/fisiologia , Cílios/fisiologia , Células-Tronco Multipotentes/fisiologia , Osteogênese/fisiologia , Análise de Variância , Cílios/ultraestrutura , Técnicas de Silenciamento de Genes , Engenharia Genética/métodos , Humanos , Microscopia de Fluorescência , Interferência de RNA , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
18.
Int J Psychophysiol ; 87(1): 81-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23183315

RESUMO

Research in the field of deception often tests participants' ability to lie about information with which they are familiar and have a strong recall of base truth. The current study examined the impact of uncertainty in memory on the ability to deceive, as may happen in real-world eye-witness scenarios. A visual misinformation paradigm was combined with event-related potentials (ERPs) to examine the impact of deception and misinformation on ERP components previously associated with deception and memory processes. Deception was associated with strong parietal P3b suppression and a large frontal negativity (N400). Misinformation was also associated with parietal P3b suppression and had effects on a late positive component (LPC) in occipital regions. The results indicate that while deception and memory uncertainty may have combined effects, they still both independently influence information processing.


Assuntos
Comunicação , Enganação , Potenciais Evocados/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Nutr Neurosci ; 15(6): 271-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22824373

RESUMO

OBJECTIVES: Various strands of evidence suggest that low intake of omega-3 fatty acids increases risk of cognitive decline and dementia. The present study investigated differences in dietary intake and blood plasma content of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) in individuals with cognitive impairment no dementia (CIND), individuals with Alzheimer's disease (AD), and healthy volunteers (HV). METHODS: A total of 135 individuals aged between 55 and 91 years (19 AD, 55 CIND, and 61 HV) were assessed predominantly within a hospital setting. RESULTS: Compared with age and sex-matched HV, individuals with AD or CIND performed poorly on a majority of tests of cognitive function. Impairment was greatest for delayed and verbal recognition memory. CIND individuals were less impaired than AD individuals. Omega-3 intake and the percentage of EPA and DHA in plasma phosphatidylcholine (PC) showed a similar pattern (AD < HV, with intermediate scores for CIND). Across the whole sample, and after controlling for age, years of education, level of socio-economic deprivation, and gender, omega-3 intake, plasma PC DHA, and plasma PC EPA were all significant positive predictors of memory functioning. DISCUSSION: These results are consistent with the possibility that omega-3 fatty acid nutrition has an impact on cognitive decline, but could equally be explained by dietary changes that occurred after onset of cognitive decline. It is also possible that the results could be explained by unknown confounding factors.


Assuntos
Doença de Alzheimer/sangue , Transtornos Cognitivos/sangue , Cognição/efeitos dos fármacos , Ácidos Graxos Ômega-3/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Dieta , Suplementos Nutricionais , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
20.
Cortex ; 47(2): 180-90, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19846073

RESUMO

Whether or not attentional mechanisms such as phasic alerting, spatial cueing and inhibition of return (IOR) remain intact in adults with Alzheimer's disease (AD) and mild cognitive impairment (MCI) remains a matter of debate. This is possibly the result of inter-study outcome variation caused by the adoption of different methodological components by different research groups. Here we investigated the influence of methodological factors upon study outcome, using a Posner-type exogenous cueing paradigm with amnestic MCI patients and healthy older controls. Specifically, we compared results when the required response involved target discrimination with results for a simple target detection response, using cue-to-target intervals (CTIs) of 200msec and 800msec in each case and with the same participants completing all conditions. For both groups, the presence or absence of both alerting and spatial cue-related effects depended upon the combination of target response requirement and CTI. Moreover, differences between the groups were specific to certain task conditions. The MCI group showed the same alerting effects as healthy people with a discrimination response, but the alerting effect shown by controls with a 200msec CTI and target detection was absent in MCI. Patients and controls showed similar spatial cue validity effects at 200msec CTI, but group differences emerged at 800msec CTI: target discrimination evoked a validity effect in the MCI group only, while target detection evoked an IOR effect in the healthy group only. These data indicate that detection and discrimination responses may each activate different attentional mechanisms, which are themselves differentially vulnerable in MCI. Thus a seemingly arbitrary choice of response may directly influence whether attentional processing appears preserved or disrupted in MCI. Furthermore, these data provide further evidence in support of the existence of significant visual attention-related functional abnormalities in amnestic MCI.


Assuntos
Envelhecimento/psicologia , Transtornos Cognitivos/psicologia , Orientação/fisiologia , Percepção Espacial/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Atenção/fisiologia , Sinais (Psicologia) , Discriminação Psicológica/fisiologia , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Percepção Visual/fisiologia
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