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2,073 result(s) for "Costa, Alberto"
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Cognitive and mental health changes and their vulnerability factors related to COVID-19 lockdown in Italy
The COVID-19 pandemic and government imposed social restrictions like lockdown exposed most individuals to an unprecedented stress, increasing mental health disorders worldwide. We explored subjective cognitive functioning and mental health changes and their possible interplay related to COVID-19-lockdown. We also investigated potential risk factors to identify more vulnerable groups. Across Italy, 1215 respondents completed our Qualtrics-based online-survey during the end of a seven to 10-week imposed lockdown and home confinement (from April 29 to May 17, 2020). We found subjective cognitive functioning and mental health severely changed in association with the lockdown. Under government regulations, cognitive complaints were mostly perceived in routine tasks involving attention, temporal orientation and executive functions—with no changes in language abilities. A paradoxical effect was observed for memory, with reduced forgetfulness compared to pre-lockdown. We found higher severity and prevalence of depression, anxiety disorders, abnormal sleep, appetite changes, reduced libido and health anxiety: with mild-to-severe depression and anxiety prevalence climbing to 32 and 36 percent, respectively, under restrictions. Being female, under 45 years, working from home or being underemployed were all identified as relevant risk factors for worsening cognition and mental health. Frequent consumers of COVID-19 mass media information or residents in highly infected communities reported higher depression and anxiety symptoms, particularly hypochondria in the latter. If similar restrictions are reimposed, governments must carefully consider these more vulnerable groups in their decisions, whilst developing effective global and long-term responses to the cognitive and mental health challenges of this type of pandemic; as well as implementing appropriate psychological interventions with specific guidelines: particularly regarding exposure to COVID-19 mass-media reports.
Protein Dynamics Associated with Failed and Rescued Learning in the Ts65Dn Mouse Model of Down Syndrome
Down syndrome (DS) is caused by an extra copy of human chromosome 21 (Hsa21). Although it is the most common genetic cause of intellectual disability (ID), there are, as yet, no effective pharmacotherapies. The Ts65Dn mouse model of DS is trisomic for orthologs of ∼55% of Hsa21 classical protein coding genes. These mice display many features relevant to those seen in DS, including deficits in learning and memory (L/M) tasks requiring a functional hippocampus. Recently, the N-methyl-D-aspartate (NMDA) receptor antagonist, memantine, was shown to rescue performance of the Ts65Dn in several L/M tasks. These studies, however, have not been accompanied by molecular analyses. In previous work, we described changes in protein expression induced in hippocampus and cortex in control mice after exposure to context fear conditioning (CFC), with and without memantine treatment. Here, we extend this analysis to Ts65Dn mice, measuring levels of 85 proteins/protein modifications, including components of MAP kinase and MTOR pathways, and subunits of NMDA receptors, in cortex and hippocampus of Ts65Dn mice after failed learning in CFC and after learning was rescued by memantine. We show that, compared with wild type littermate controls, (i) of the dynamic responses seen in control mice in normal learning, >40% also occur in Ts65Dn in failed learning or are compensated by baseline abnormalities, and thus are considered necessary but not sufficient for successful learning, and (ii) treatment with memantine does not in general normalize the initial protein levels but instead induces direct and indirect responses in approximately half the proteins measured and results in normalization of the endpoint protein levels. Together, these datasets provide a first view of the complexities associated with pharmacological rescue of learning in the Ts65Dn. Extending such studies to additional drugs and mouse models of DS will aid in identifying pharmacotherapies for effective clinical trials.
On the Therapeutic Use of Monoclonal Antibodies Against Amyloid Plaques in Older Adults with Down Syndrome: A Narrative Review and Perspective
Down syndrome (DS) is a genetic disorder caused by an extra copy of chromosome 21 (trisomy 21 or T21) and is associated with an increased risk of early-onset Alzheimer’s disease (AD), also known as DS-associated AD (DSAD). Individuals with DS typically develop amyloid neuropathology in their late-thirties to early-forties and the mean age of onset of clinical dementia is approximately 55 years. Recent advances in AD clinical research have focused on monoclonal antibodies (mAbs) targeting amyloid-β (Aβ) plaques as a potential therapeutic approach. Therefore, there has been guarded enthusiasm about using anti-amyloid mAbs in the prevention/treatment of DSAD. This narrative review and perspective explores the current understanding of amyloid pathology in AD and DSAD, the rationale for using anti-amyloid mAbs in the treatment of DSAD, and the challenges and opportunities for research toward the application of this therapeutic strategy to older adults with DS.
Forward and backward span for verbal and visuo-spatial data: standardization and normative data from an Italian adult population
The Digit span and Corsi span tasks are frequently used to assess verbal and visuo-spatial short-term memory. Forward versions of these tasks, in which sequences of items of increasing length have to be reproduced in the order they were presented, are believed to primarily evaluate the functioning of the working memory material-specific slave systems (i.e. the phonological loop and the visuo-spatial sketchpad for verbal and visuo-spatial data, respectively). The backward versions of both tasks, in which sequences of items have to be reproduced in the reverse order, are believed to primarily tax Central Executive resources. Here, we report normative data on the forward and backward versions of the Digit span and Corsi span tasks that was collected from 362 healthy Italians ranging in age from 20 to 90 years. The results show a decremental effect of age on performance in all tasks and an ameliorative effect of education in all tasks except the Corsi span backwards. We provide correction grids for age and literacy that derive from results of the regression analyses.
Atypical electrophysiological and behavioral responses to diazepam in a leading mouse model of Down syndrome
Mounting evidence implicates dysfunctional GABA A R-mediated neurotransmission as one of the underlying causes of learning and memory deficits observed in the Ts65Dn mouse model of Down syndrome (DS). The specific origin and nature of such dysfunction is still under investigation, which is an issue with practical consequences to preclinical and clinical research, as well as to the care of individuals with DS and anxiety disorder or those experiencing seizures in emergency room settings. Here, we investigated the effects of GABA A R positive allosteric modulation (PAM) by diazepam on brain activity, synaptic plasticity, and behavior in Ts65Dn mice. We found Ts65Dn mice to be less sensitive to diazepam, as assessed by electroencephalography, long-term potentiation, and elevated plus-maze. Still, diazepam pre-treatment displayed typical effectiveness in reducing susceptibility and severity to picrotoxin-induced seizures in Ts65Dn mice. These findings fill an important gap in the understanding of GABAergic function in a key model of DS.
Imagine, Discover, Inspire: Proceedings of the 4th International Conference of the Trisomy 21 Research Society
Down syndrome (DS) or trisomy 21 (T21) is present in a significant number of children and adults around the world and is associated with cognitive and medical challenges. Through research, the T21 Research Society (T21RS), established in 2014, unites a worldwide community dedicated to understanding the impact of T21 on biological systems and improving the quality of life of people with DS across the lifespan. T21RS hosts an international conference every two years to support collaboration, dissemination, and information sharing for this goal. In 2022, T21RS hosted an international conference in Long Beach, California, from June 9 to 12. The conference, attended by 483 people including scientists, families, self-advocates, and industry representatives from 17 countries, was a dynamic and interactive meeting that shared discoveries from international research teams. This summary highlights the scientific discoveries shared at the 4th T21RS meeting with the Imagine, Discover, Inspire theme.
Baseline Neuropsychological Characteristics of Adolescents and Young Adults with Down Syndrome Who Participated in Two Clinical Trials of the Drug Memantine
Background/Objectives: Down syndrome (DS) is a neurodevelopmental and neurodegenerative disorder typically caused by trisomy 21. We recently concluded a two-site (Ohio, USA and São Paulo, Brazil), phase-2, randomized trial to evaluate the efficacy, tolerability, and safety of the drug memantine in enhancing cognitive abilities of adolescents and young adults with DS. This trial was a follow-up study to a pilot trial performed in Colorado, USA. Results of these two clinical trials have been published elsewhere. Here, we present a comparative analysis of the baseline neuropsychological assessments at the three sites of these two studies, including their psychometric properties, and an account of the considerations involved in the test battery design. We compared test results in the different sites as a way of evaluating the replicability and generalizability of the test results. The distribution of the test results at each site was analyzed and combined when no differences were detected between the mean values of these results. We used post-treatment data from the placebo arms of these studies to quantify test–retest reliability. Results: Most measures had comparable mean values across test sites, and had good-to-excellent feasibility, few floor effects, and good-to-excellent test–retest reliability. A few measures, however, were deemed unsuitable for use in future studies. Conclusions: This study demonstrated remarkable consistency of results across studies in two countries with significantly different cultures and levels of socioeconomic development, which provides supporting evidence for the future design and implementation of similar multicenter, international clinical studies involving participants with DS.
Biologically Active Metabolites Synthesized by Microalgae
Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences.
Acute Injections of the NMDA Receptor Antagonist Memantine Rescue Performance Deficits of the Ts65Dn Mouse Model of Down Syndrome on a Fear Conditioning Test
Individuals with Down syndrome (DS) and Ts65Dn mice (a major animal model of DS) carry an extra copy of the DSCR1 (Down Syndrome Critical Region 1) gene, which encodes for a protein that inhibits calcineurin. Calcineurin itself has been shown to modulate N -methyl- D -aspartate (NMDA) receptor (NMDAR) activation kinetics by decreasing channel mean open time and opening probability. We hypothesize that the overexpression of DSCR1 in persons with DS and Ts65Dn mice would inhibit normal calcineurin activity and produce pathological increases in NMDAR mean open time and opening probability. These kinetic changes should in turn produce an increase in inhibition of NMDAR-mediated currents by open channel blockers. To test this hypothesis, we investigated the locomotor-stimulating effects of MK-801 on Ts65Dn mice and have found that these mice display an increased sensitivity to this compound. Furthermore, we have found that acute injections (5 mg/kg, i.p.) of the uncompetitive NMDAR antagonist memantine rescue performance deficits of Ts65Dn mice on a fear conditioning test. Because the actions of memantine on NMDAR kinetics had been shown by others to mimic somewhat the actions of calcineurin, we attributed this positive effect of memantine on Ts65Dn mice to a drug-mediated ‘normalization’ of NMDAR function. To our knowledge, this is the first instance in which the acute injection of a pharmacological agent has improved the behavioral performance of Ts65Dn mice in a test of learning and memory. These results are very promising from a potential therapeutic perspective, given memantine's current status as a Food and Drug Administration (FDA)-approved drug.
Human Sensory Neurons Derived from Induced Pluripotent Stem Cells Support Varicella-Zoster Virus Infection
After primary infection, varicella-zoster virus (VZV) establishes latency in neurons of the dorsal root and trigeminal ganglia. Many questions concerning the mechanism of VZV pathogenesis remain unanswered, due in part to the strict host tropism and inconsistent availability of human tissue obtained from autopsies and abortions. The recent development of induced pluripotent stem (iPS) cells provides great potential for the study of many diseases. We previously generated human iPS cells from skin fibroblasts by introducing four reprogramming genes with non-integrating adenovirus. In this study, we developed a novel protocol to generate sensory neurons from iPS cells. Human iPS cells were exposed to small molecule inhibitors for 10 days, which efficiently converted pluripotent cells into neural progenitor cells (NPCs). The NPCs were then exposed for two weeks to growth factors required for their conversion to sensory neurons. The iPS cell-derived sensory neurons were characterized by immunocytochemistry, flow cytometry, RT-qPCR, and electrophysiology. After differentiation, approximately 80% of the total cell population expressed the neuron-specific protein, βIII-tubulin. Importantly, 15% of the total cell population co-expressed the markers Brn3a and peripherin, indicating that these cells are sensory neurons. These sensory neurons could be infected by both VZV and herpes simplex virus (HSV), a related alphaherpesvirus. Since limited neuronal populations are capable of supporting the entire VZV and HSV life cycles, our iPS-derived sensory neuron model may prove useful for studying alphaherpesvirus latency and reactivation.