RESUMO
The renal vasopressin V(2) receptor (V(2)R) plays a critical role in physiological and pathophysiological processes associated with arginine vasopressin (AVP)-induced antidiuresis. Because clinical data suggests that females may be more prone to hyponatremia from AVP-mediated antidiuresis, we investigated whether there are sex differences in the expression and function of the renal V(2)R. In normal Sprague-Dawley rat kidneys, V(2)R mRNA and protein expression was 2.6- and 1.7-fold higher, respectively, in females compared with males. To investigate the potential physiological implications of this sex difference, we studied changes in urine osmolality induced by the AVP V(2)R agonist desmopressin. In response to different doses of desmopressin, there was a graded increase in urine osmolality and decrease in urine volume during a 24-h infusion. Females showed greater mean increases in urine osmolality and greater mean decreases in urine volume at 0.5 and 5.0 ng/h infusion rates. We also studied renal escape from antidiuresis produced by water loading in rats infused with desmopressin (5.0 ng/h). After 5 days of water loading, urine osmolality of both female and male rats escaped to the same degree physiologically, but V(2)R mRNA and protein in female kidneys was reduced to a greater degree (-63% and -73%, respectively) than in males (-32% and -48%, respectively). By the end of the 5-day escape period, renal V(2)R mRNA and protein expression were reduced to the same relative levels in males and females, thereby abolishing the sex differences in V(2)R expression seen in the basal state. Our results demonstrate that female rats express significantly more V(2)R mRNA and protein in kidneys than males, and that this results physiologically in a greater sensitivity to V(2)R agonist administration. The potential pathophysiological implications of these results are that females may be more susceptible to the development of dilutional hyponatremia because of a greater sensitivity to endogenously secreted AVP.
Assuntos
Arginina Vasopressina/metabolismo , Diurese , Receptores de Vasopressinas/metabolismo , Animais , Antidiuréticos/farmacologia , Aquaporina 2/metabolismo , Arginina Vasopressina/antagonistas & inibidores , Desamino Arginina Vasopressina/farmacologia , Feminino , Humanos , Hiponatremia/metabolismo , Masculino , Concentração Osmolar , Ratos , Receptores de Vasopressinas/análise , Fatores Sexuais , Urina/químicaRESUMO
BACKGROUND: To reduce the risk of patient handling-related musculoskeletal injury, overhead ceiling lifts have been installed in health care facilities. To increase ceiling lift usage for a variety of patient handling tasks, a peer coaching and mentoring program was implemented among the direct care staff in the long-term care subsector in British Columbia, Canada. They received a 4-day training program on body mechanics, ergonomics, patient-handling techniques, ceiling lift usage, in addition to coaching skills. METHODS: A questionnaire was administered among staff before and after the intervention to evaluate the program's effectiveness. RESULTS: There were 403 and 200 respondents to the pre-intervention and post-intervention questionnaires. In general, staff perceived the peer-coaching program to be effective. The number of staff who reported to be using ceiling lifts "often and always" went higher from 64.5% to 80.5% (<0.001) after coaching program implementation. Furthermore, staff reported that they were using the ceiling lifts for more types of tasks post-intervention. Staff reported that the peer coaching program has increased their safety awareness at work and confidence in using the ceiling lifts. CONCLUSIONS: The findings suggest that this educational model can increase the uptake of mechanical interventions for occupational health and safety initiatives. It appears that the training led to a greater awareness of the availability of or increased perceptions of the number of ceiling lifts, presumably through coaches advocating their use.
Assuntos
Pessoal de Saúde/educação , Movimentação e Reposicionamento de Pacientes/métodos , Grupo Associado , Segurança , Ensino/métodos , Adulto , Idoso , Colúmbia Britânica , Feminino , Humanos , Masculino , Mentores , Pessoa de Meia-Idade , Movimentação e Reposicionamento de Pacientes/instrumentação , Inquéritos e QuestionáriosRESUMO
To synthesize current knowledge of the impact of pediatric neuropsychological evaluations on child functioning, we conducted a systematic review of the literature on parents' overall satisfaction with their child's evaluation and perceptions of how helpful the evaluation was for understanding their child's abilities and how useful the evaluation was for providing actionable information to elicit change. Parent satisfaction is important in this context because studies on healthcare consumption indicate a substantial relationship between patient satisfaction with services and implementation of recommendations and follow-up care. We followed PRISMA guidelines to conduct a systematic review of the literature on parent perception of pediatric neuropsychological evaluations for children aged 3-21 years. Using a set of predefined search terms, we identified 1,163 abstracts across PubMed, PsycINFO, Cochrane Library, and Web of Science electronic databases and included 12 studies in our qualitative synthesis. In general, parents reported high levels of satisfaction with their child's evaluation. Feedback from the evaluation was helpful for understanding their child's pattern of strengths and weaknesses and included useful information for obtaining support. Although parents did report improvement in their child's functional participation in home, school, and community settings, they tended to rate the usefulness of the evaluation for eliciting change lower than their overall satisfaction with the evaluation or how helpful the evaluation was for understanding their child's abilities. Additional effort appears to be needed for pediatric neuropsychological evaluations recommendations to result in durable, meaningful change in child functioning.
Assuntos
Família , Pais , Criança , Humanos , Testes Neuropsicológicos , Percepção , Satisfação PessoalRESUMO
Past research suggests that children begin to phonologically rehearse at around 7 years of age. Less is known regarding the development of refreshment, an attention-based maintenance mechanism. Therefore, the use of these two maintenance methods by 6- and 8-year-olds was assessed using memory span tasks that varied in their opportunities for maintenance activity. Experiment 1 showed that nonverbal processing impaired both groups' performance to similar extents. Experiment 2 employed phonologically similar or dissimilar memory items and compared the effects of verbal versus nonverbal processing on recall. Both groups showed evidence of phonological maintenance under nonverbal processing but not under verbal processing. Furthermore, nonverbal processing again impaired recall. Verbal processing was also more detrimental to performance in 8-year-olds than in 6-year-olds. Together, the results suggest that nonverbal processing impairs recall by obstructing refreshment and that developmental change in maintenance between 6 and 8 years of age consists primarily of an increase in phonological rehearsal.
Assuntos
Atenção/fisiologia , Desenvolvimento Infantil/fisiologia , Memória de Curto Prazo/fisiologia , Fonética , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Rememoração Mental/fisiologia , Análise e Desempenho de TarefasRESUMO
Long-term care staff have high levels of musculoskeletal concerns. This research provided a pilot program to evaluate the efficacy of employer-funded on-site massage therapy on job satisfaction, workplace stress, pain, and discomfort. Twenty-minute massage therapy sessions were provided. Evaluation demonstrated possible improvements in job satisfaction, with initial benefits in pain severity, and the greatest benefit for individuals with preexisting symptoms. A long-term effect was not demonstrated.
Assuntos
Esgotamento Profissional/prevenção & controle , Pessoal de Saúde/psicologia , Satisfação no Emprego , Massagem/organização & administração , Serviços de Saúde do Trabalhador/organização & administração , Dor/prevenção & controle , Adulto , Atitude do Pessoal de Saúde , Colúmbia Britânica , Esgotamento Profissional/diagnóstico , Esgotamento Profissional/psicologia , Análise Fatorial , Feminino , Humanos , Masculino , Massagem/psicologia , Pessoa de Meia-Idade , Dor/diagnóstico , Dor/psicologia , Medição da Dor , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Instituições Residenciais , Índice de Gravidade de Doença , Inquéritos e Questionários , Carga de Trabalho , Local de Trabalho/organização & administração , Local de Trabalho/psicologiaRESUMO
We ask the question: Which aspects of immediate memory performance improve with age? In two studies, we reexamine the widely held view that primary memory capacity estimates derived from children's immediate free recall are age invariant. This was done by assessing children's immediate free-recall accuracy while also measuring the order in which they elected to recall items (Experiment 1) and by encouraging children to begin free recall with items from towards the end of the presented list (Experiment 2). Across samples aged between 5 and 8 years we replicated the previously reported age-related changes in free-recall serial position functions when aggregated across all trials of the standard task, including an absence of age differences in the recency portion of this curve. However, we also show that this does not reflect the fact that primary memory capacity is constant across age. Instead, when we incorporate order of report information, clear age differences are evident in the recall of list-final items that are output at the start of a participant's response. In addition, the total amount that individuals recalled varied little across different types of free-recall tasks. These findings have clear implications for the use of immediate free recall as a means of providing potential indices of primary memory capacity and in the study of the development of immediate memory.
Assuntos
Desenvolvimento Infantil , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Aprendizagem Verbal/fisiologiaRESUMO
OBJECTIVE: Suboptimal functioning of the basal ganglia is implicated in attention-deficit/hyperactivity disorder (ADHD). These structures are important to the acquisition of associative knowledge, leading some to theorize that associative learning deficits might be expected, despite the fact that most extant research in ADHD has focused on effortful control. We present 2 studies that examined the acquisition of explicit rule-based (RB) and associative information integration (II) category learning among school-age children with ADHD. METHOD AND RESULTS: In Study 1, we found deficits in both RB and II category learning tasks among children with ADHD (n = 81) versus controls (n = 42). Children with ADHD tended to sort by the more salient but irrelevant dimension (in the RB paradigm) and were unable to acquire a consistent sorting strategy (in the II paradigm). To disentangle whether the deficit was localized to II category learning versus a generalized inability to consider more than 1 stimulus dimension, in Study 2 children completed a conjunctive RB paradigm that required consideration of 2 stimulus dimensions. Children with ADHD (n = 50) continued to underperform controls (n = 33). CONCLUSIONS: Results provide partial support for neurocognitive developmental theories of ADHD that suggest that associative learning deficits should be found, and highlight the importance of using analytic approaches that go beyond asking whether an ADHD-related deficit exists to why such deficits exist.
Assuntos
Aprendizagem por Associação/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Formação de Conceito/fisiologia , Deficiências da Aprendizagem/etiologia , Criança , Feminino , Humanos , Inteligência , Deficiências da Aprendizagem/diagnóstico , Masculino , Testes NeuropsicológicosRESUMO
We examined whether error monitoring, operationalized as the degree to which individuals slow down after committing an error (i.e., posterror slowing), is differentially important in the learning of rule-based versus information-integration category structures. Rule-based categories are most efficiently solved through the application of an explicit verbal strategy (e.g., "sort by color"). In contrast, information-integration categories are believed to be learned in a trial-by-trial, associative manner. Our results indicated that posterror slowing predicts enhanced rule-based but not information-integration category learning. Implications for multiple category-learning systems are discussed.
Assuntos
Formação de Conceito/fisiologia , Conhecimento Psicológico de Resultados , Aprendizagem/fisiologia , Tempo de Reação/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Adulto JovemRESUMO
The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is frequently responsible for chronic hyponatremia in the elderly due to age-related disruption of the inhibitory component of brain osmoregulatory mechanisms. Recent research has indicated that chronic hyponatremia is associated with gait disturbances, increased falls, and bone fragility in humans, and we have found that chronic hyponatremia causes increased bone resorption and reduced bone mineral density in young rats. In this study, we used a model of SIADH to study multi-organ consequences of chronic hyponatremia in aged rats. Sustained hyponatremia for 18 weeks caused progressive reduction of bone mineral density by DXA and decreased bone ash calcium, phosphate and sodium contents at the tibia and lumbar vertebrae. Administration of 10-fold higher vitamin D during the last 8 weeks of the study compensated for the reduction in bone formation and halted bone loss. Hyponatremic rats developed hypogonadism, as indicated by slightly lower serum testosterone and higher serum FSH and LH concentrations, markedly decreased testicular weight, and abnormal testicular histology. Aged hyponatremic rats also manifested decreased body fat, skeletal muscle sarcopenia by densitometry, and cardiomyopathy manifested as increased heart weight and perivascular and interstitial fibrosis by histology. These findings are consistent with recent results in cultured osteoclastic cells, indicating that low extracellular sodium concentrations increased oxidative stress, thereby potentially exacerbating multiple manifestations of senescence. Future prospective studies in patients with SIADH may indicate whether these multi-organ age-related comorbidities may potentially contribute to the observed increased incidence of fractures and mortality in this population.
Assuntos
Envelhecimento/metabolismo , Hipogonadismo/etiologia , Hiponatremia/complicações , Vértebras Lombares/química , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Vitamina D/farmacologia , Absorciometria de Fóton , Análise de Variância , Animais , Biomarcadores/sangue , Densidade Óssea , Cálcio/sangue , Cardiomiopatias/etiologia , Doença Crônica , Síndrome de Secreção Inadequada de HAD/complicações , Masculino , Concentração Osmolar , Estresse Oxidativo , Ratos , Ratos Endogâmicos F344 , Sarcopenia/etiologia , Sódio/sangue , Redução de PesoRESUMO
We meta-analytically review 47 between-groups studies of continuous performance test (CPT) performance in children with attention-deficit/hyperactivity disorder (ADHD). Using a random effects model and correcting for both sampling error and measurement unreliability, we found large effect sizes (δ) for overall performance, but only small to moderate δ for performance over time in the handful of studies that reported that data. Smaller δs for performance over time are likely attributable, in part, to the extensive use of stimuli for which targets and distractors are quite easily differentiated. Artifacts accounted for a considerable proportion of variance among observed δs. Effect sizes reported in previous reviews were significantly attenuated because of the presence of uncorrected artifacts and highlight the necessity of accounting for artifactual variance in future work to determine the amount of true neurocognitive heterogeneity within ADHD. Signal detection theory and diffusion modeling analyses indicated that the ADHD-related deficits were because of decreased perceptual sensitivity (d') and slower drift rates (v). Results are interpreted the context of several recent models of ADHD.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Atenção , Criança , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Percepção , Desempenho Psicomotor/fisiologia , Tempo de Reação , Tamanho da AmostraRESUMO
Two studies that examine whether the forgetting caused by the processing demands of working memory tasks is domain-general or domain-specific are presented. In each, separate groups of adult participants were asked to carry out either verbal or nonverbal operations on exactly the same processing materials while maintaining verbal storage items. The imposition of verbal processing tended to produce greater forgetting even though verbal processing operations took no longer to complete than did nonverbal processing operations. However, nonverbal processing did cause forgetting relative to baseline control conditions, and evidence from the timing of individuals' processing responses suggests that individuals in both processing groups slowed their responses in order to "refresh" the memoranda. Taken together the data suggest that processing has a domain-general effect on working memory performance by impeding refreshment of memoranda but can also cause effects that appear domain-specific and that result from either blocking of rehearsal or interference.
Assuntos
Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação , Comportamento Verbal/fisiologia , Adulto JovemRESUMO
The effect of potentially distracting processing within working memory was examined by varying the nature and position of processing across conditions of a Brown-Peterson-like task. Separate groups of participants carried out verbal or visuospatial processing operations on identical stimuli, while retaining lists of to-be-remembered words. The number of words presented either before or after the processing interval was varied systematically. Results showed that although verbal processing was no more demanding than visuospatial processing, it led to greater forgetting. However, forgetting was confined to items presented prior to processing, and the difference in degree of forgetting shown by the two groups was maximal when four items occurred before processing. Temporal isolation effects were more marked in the verbal processing group. These findings indicate that individuals can keep active a limited number of items in primary memory during processing, unless processing blocks rehearsal, in which case retrieval occurs from secondary memory.
Assuntos
Memória de Curto Prazo , Animais , Atenção , Sinais (Psicologia) , Aprendizagem , Aprendizagem Seriada , Aprendizagem VerbalRESUMO
Sex steroids influence the development and function of the songbird brain. Developmentally, the neural circuitry underlying song undergoes masculine differentiation under the influence of estradiol. In adults, estradiol stimulates song behavior and the seasonal growth of song control circuits. There is good reason to believe that these neuroactive estrogens are synthesized in the brain. At all ages, estrogens could act at the lateral ventricle, during migration, or where song nuclei exist or will form. We investigated the activity of two critical steroidogenic enzymes, 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD) and aromatase, using a slice culture system. Sagittal brain slices were collected from juvenile (posthatch day 20) and adult zebra finches containing either the lateral ventricle, where neurons are born, or the telencephalic song nuclei HVC and RA. The slices were incubated with (3)H-dehydroepiandrosterone or (3)H-androstenedione. Activity was determined by isolating certain products of 3beta-HSD (5alpha-androstanedione, 5beta-androstanedione, estrone, and estradiol) and aromatase (estrone and estradiol). Activities of both 3beta-HSD and aromatase were detected in all slices and were confirmed using specific enzyme inhibitors. We found no significant difference in activity between adult males and females in either region for either enzyme. Juvenile female slices containing the lateral ventricle, however, showed greater levels of 3beta-HSD activity than did similar slices from age-matched males. Determination of the activity of these critical steroidogenic enzymes in slice culture has implications for the role of neurosteroids in brain development.
Assuntos
Aromatase/metabolismo , Tentilhões/metabolismo , Centro Vocal Superior/enzimologia , Ventrículos Laterais/enzimologia , Complexos Multienzimáticos/metabolismo , Progesterona Redutase/metabolismo , Esteroide Isomerases/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , Fatores Etários , Androstenodiona/metabolismo , Animais , Desidroepiandrosterona/metabolismo , Feminino , Tentilhões/crescimento & desenvolvimento , Centro Vocal Superior/crescimento & desenvolvimento , Ventrículos Laterais/crescimento & desenvolvimento , Masculino , Análise por Pareamento , Técnicas de Cultura de Órgãos , Fatores Sexuais , Estatísticas não ParamétricasRESUMO
Three experiments, using the original encoding-specificity paradigm, investigated the role of study list structure in producing Higham and Tam's (2005) generation failure effect. Generation failure occurs when cued recall performance for strong, extralist cues is worse than target production in a control group that is given no study list but is instead required merely to generate responses to the same test cues. In the present study, generation failure was replicated in Experiment 1, and Experiment 2 demonstrated that strong, extralist cues were more likely to elicit targets in pure generation groups when participants had studied a list of strong associates than when they had studied a list of weak ones. In Experiment 3, participants were released from generation failure when a study list of moderate associates was used and the cue-to-target associative strength was equated between the reinstated- and extralist-cue conditions. Together, these results suggest that generation failure is partly attributable to participants' searching inappropriate domains that, though consistent with the study list structure, are unlikely to contain targets.