257 research outputs found

    Selective Attention and Sensory Modality in Aging: Curses and Blessings

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    The notion that selective attention is compromised in older adults as a result of impaired inhibitory control is well established. Yet it is primarily based on empirical findings covering the visual modality. Auditory and, especially, cross-modal selective attention are remarkably underexposed in the literature on aging. In the past five years, we have attempted to fill these voids by investigating performance of younger and older adults on equivalent tasks covering all four combinations of visual or auditory target, and visual or auditory distractor information. In doing so, we have demonstrated that older adults are especially impaired in auditory selective attention with visual distraction. This pattern of results was not mirrored by the results from our psychophysiological studies, however, in which both enhancement of target processing and suppression of distractor processing appeared to be age equivalent. We currently conclude that (1) age-related differences of selective attention are modality dependent, (2) age-related differences of selective attention are limited, and (3) it remains an open question whether modality-specific age differences in selective attention are due to impaired distractor inhibition, impaired target enhancement, or both. These conclusions put the longstanding inhibitory deficit hypothesis of aging in a new perspective

    Remedial Effects of Motivational Incentive on Declining Cognitive Control In Healthy Aging and Parkinson's Disease

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    The prospect of reward may provide a motivational incentive for optimizing goal-directed behavior. Animal work demonstrates that reward-processing networks and oculomotor-control networks in the brain are connected through the dorsal striatum, and that reward anticipation can improve oculomotor control via this nexus. Due perhaps to deterioration in dopaminergic striatal circuitry, goal-directed oculomotor control is subject to decline in healthy seniors, and even more in individuals with Parkinson's disease (PD). Here we examine whether healthy seniors and PD patients are able to utilize reward prospects to improve their impaired antisaccade performance. Results confirmed that oculomotor control declined in PD patients compared to healthy seniors, and in healthy seniors compared to young adults. However, the motivational incentive of reward expectation resulted in benefits in antisaccade performance in all groups alike. These findings speak against structural and non-modifiable decline in cognitive control functions, and emphasize the remedial potential of motivational incentive mechanisms in healthy as well as pathological aging

    Tuning the Biological Activity of Camphorimine Complexes through Metal Selection

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    This research was funded by FCT—Fundação para a Ciência e a Tecnologia, through projects CQE (UIDB/00100/2020 and UIDP/00100/2020) and C2TN (UID/MULTI/04349/2019), the projects of the Research Unit Institute for Bioengineering and Biosciences—iBB (UIDB/04565/2020 and UIDP/04565/2020), the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB, and a PhD grant to J.P.C. (UI/BD/152244/2021).The cytotoxic activity of four sets of camphorimine complexes based on the Cu(I), Cu(II), Ag(I), and Au(I) metal sites were assessed against the cisplatin-sensitive A2780 and OVCAR3 ovarian cancer cells. The results showed that the gold complexes were ca. one order of magnitude more active than the silver complexes, which in turn were ca. one order of magnitude more active than the copper complexes. An important finding was that the cytotoxic activity of the Ag(I) and Au(I) camphorimine complexes was higher than that of cisplatin. Another relevant aspect was that the camphorimine complexes did not interact significantly with DNA, in contrast with cisplatin. The cytotoxic activity of the camphorimine complexes displayed a direct relationship with the cellular uptake by OVCAR3 cells, as ascertained by PIXE (particle-induced X-ray emission). The levels of ROS (reactive oxygen species) formation exhibited an inverse relationship with the reduction potentials for the complexes with the same metal, as assessed by cyclic voltammetry. In order to gain insight into the toxicity of the complexes, their cytotoxicity toward nontumoral cells (HDF and V79 fibroblasts) was evaluated. The in vivo cytotoxicity of complex 5 using the nematode Caenorhabditis elegans was also assessed. The silver camphorimine complexes displayed the highest selectivity coefficients (activity vs. toxicity).publishersversionpublishe

    Diagnostic accuracy of ultrasound signs for detecting adnexal torsion: systematic review and meta-analysis

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    Objective: To evaluate the diagnostic accuracy of different ultrasound signs for diagnosing adnexal torsion, using surgery as the reference standard. Methods: This was a systematic review and meta-analysis of studies published between January 1990 and November 2021 evaluating ovarian edema, adnexal mass, ovarian Doppler flow findings, the whirlpool sign and pelvic fluid as ultrasound signs (index tests) for detecting adnexal torsion, using surgical findings as the reference standard. The search for studies was performed in PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov and Web of Science databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to evaluate the quality of the studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated separately, and the post-test probability of adnexal torsion following a positive or negative test was also determined. Results: The search identified 1267 citations after excluding duplicates. Eighteen studies were ultimately included in the qualitative and quantitative syntheses. Eight studies (809 patients) analyzed the presence of ovarian edema, eight studies (1044 patients) analyzed the presence of an adnexal mass, 14 studies (1742 patients) analyzed ovarian Doppler flow, six studies (545 patients) analyzed the whirlpool sign and seven studies (981 patients) analyzed the presence of pelvic fluid as ultrasound signs of adnexal torsion. Overall, the quality of most studies was considered to be moderate or good. However, there was a high risk of bias in the patient-selection and index-text domains (with the exception of the whirlpool sign) in a significant proportion of studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios of each ultrasound sign were 58%, 86%, 4.0 and 0.49 for ovarian edema, 69%, 46%, 1.3 and 0.67 for adnexal mass, 65%, 91%, 7.6 and 0.38 for the whirlpool sign, 53%, 95%, 11.0 and 0.49 for ovarian Doppler findings and 55%, 69%, 1.7 and 0.66 for pelvic fluid. Heterogeneity was high for all analyses. Conclusions: The presence of an adnexal mass or pelvic fluid have poor diagnostic accuracy as ultrasound signs of adnexal torsion, while the presence of ovarian edema, the whirlpool sign and decreased or absent ovarian Doppler flow have good specificity but moderate sensitivity for detecting adnexal torsion. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.Objetivo.Evaluar la precision diagnostica de diferentes indicios ecograficos para el diagnostico de la torsion anexial,utilizando la cirugia como patron de referencia. Metodos. Se trata de una revision sistematica y un metaanalisis de los estudios publicados entre enero de 1990 y noviembre de 2021 que evaluaron el edema ovarico, la masa anexial, los resultados del flujo Doppler ovarico, el ‘‘signo del remolino’’ (torsion ovarica) y el liquido pelvico como indicios ecograficos (pruebas de referencia) para detectar la torsion anexial, utilizando los resultados quirurgicos como patron de referencia. La busqueda de estudios se realizo en las bases de datos PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov y Web of Science.Para evaluar la calidad de los estudios se utilizo la herramienta de Evaluacion de Calidad de los Estudios de Precision Diagnostica-2 (QUADAS-2, por sus siglas en ingles). Se calcularon por separado los valores combinados de sensibilidad,especificidad y cocientes de verosimilitud positivos y negativos, y se determino tambien la probabilidad posterior a la prueba de la torsion anexial tras una prueba positiva o negativa. Resultados. La busqueda identifico 1267 citas, una vez excluidas las duplicadas. Se incluyeron dieciocho estudios en las sıntesis cualitativa y cuantitativa. Ocho estudios (809 pacientes) analizaron la presencia de edema ovarico, ocho estudios(1044 pacientes) analizaron la presencia de una masa anexial, 14 estudios (1742 pacientes) analizaron el flujo Doppler ovarico, seis estudios (545 pacientes) analizaron el ‘‘signo del remolino’’ y siete estudios (981 pacientes) analizaron la presencia de lıquido pelvico como indicios ecograficos de torsion anexial. En general, la calidad de la mayorıa de los estudios se considero moderada o buena. Sin embargo, hubo un alto riesgo de sesgo en una proporcion significativa de estudios en las areas de seleccion de pacientes y texto de referencia (con la excepcion del ‘‘signo del remolino’’). Los valores combinados de la sensibilidad, la especificidad y los cocientes de probabilidad positivos y negativos de cada indicio ecografico fueron del 58%, 86%, 4,0 y 0,49 para el edema ovarico, del 69%, 46%, 1,3 y 0,67 para la masa anexial, del 65%, 91%, 7,6 y 0,38 para el ‘‘signo del remolino’’, del 53%, 95%, 11,0 y 0,49 para los resultados del Doppler ovarico y del 55%, 69%, 1,7 y 0,66 para el liquido pelvico. La heterogeneidad fue elevada en todos los analisis. Conclusion. La presencia de una masa anexial o de liquido pelvico apenas tienen precision diagnostica como indicios ecograficos de torsion anexial, mientras que la presencia de edema ovarico, el ‘‘signo del remolino’’ y la disminucion o ausencia de flujo Doppler ovarico tienen una buena especificidad, pero una sensibilidad moderada para detectar la torsion anexial

    Burden, coping, physical symptoms and psychological morbidity in caregivers of functionally dependent family members

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    Objectives: this study assessed burden, coping, physical symptoms and psychological morbidity in caregivers of functionally dependent family members. Methods: fifty family caregivers completed self-reported measures of burden, physical symptoms, psychological morbidity and coping strategies. Results: there was a significant negative correlation between coping strategies and the different clinical variables, as well as a significant positive correlation between coping strategies and duration of care. It appears that the stronger bond between caregiver and family member leads to a poorer use of adaptive coping strategies. It also appears that the deterioration of the relationship between them and the lower perceived self-efficacy are more prominente in caregivers of family members with cognitive impairment, indicating that caregivers with family members without cognitive impairment face fewer difficulties. Conclusion: these results emphasize the need for interventions to include coping strategies, since they are important in reducing caregivers’ burden, psychological morbidity and physical symptoms

    New endoperoxides highly active in vivo and in vitro against artemisinin-resistant Plasmodium falciparum

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    Background: The emergence and spread of Plasmodium falciparum resistance to artemisinin-based combination therapy in Southeast Asia prompted the need to develop new endoperoxide-type drugs. Methods: A chemically diverse library of endoperoxides was designed and synthesized. The compounds were screened for in vitro and in vivo anti-malarial activity using, respectively, the SYBR Green I assay and a mouse model. Ring survival and mature stage survival assays were performed against artemisinin-resistant and artemisinin-sensitive P. falciparum strains. Cytotoxicity was evaluated against mammalian cell lines V79 and HepG2, using the MTT assay. Results: The synthesis and anti-malarial activity of 21 new endoperoxide-derived compounds is reported, where the peroxide pharmacophore is part of a trioxolane (ozonide) or a tetraoxane moiety, flanked by adamantane and a substituted cyclohexyl ring. Eight compounds exhibited sub-micromolar anti-malarial activity (IC50 0.3–71.1 nM), no cross-resistance with artemisinin or quinolone derivatives and negligible cytotoxicity towards mammalian cells. From these, six produced ring stage survival < 1% against the resistant strain IPC5202 and three of them totally suppressed Plasmodium berghei parasitaemia in mice after oral administration. Conclusion: The investigated, trioxolane–tetrazole conjugates LC131 and LC136 emerged as potential anti-malarial candidates; they show negligible toxicity towards mammalian cells, ability to kill intra-erythrocytic asexual stages of artemisinin-resistant P. falciparum and capacity to totally suppress P. berghei parasitaemia in mice.info:eu-repo/semantics/publishedVersio
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