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1.
Orthop J Sports Med ; 12(5): 23259671241249132, 2024 May.
Article in English | MEDLINE | ID: mdl-38751851

ABSTRACT

Background: The anatomy of the trochlea plays a significant role in patellar stability. The developmental anatomy of the trochlea and its relationship to patellar stability remains poorly understood. Purpose: To describe the developmental changes of the osseous and cartilaginous trochlear morphology in skeletally immature specimens. Study Design: Descriptive laboratory study. Methods: A total of 65 skeletally immature cadaveric knees between the ages of 2 months and 11 years were evaluated using computed tomography scans. The measurements in the axial plane of both cartilage and bone include medial, central, and lateral trochlear height; sulcus height; medial and later trochlear facet length; trochlear sulcus angle; patellar sulcus angle; condylar height asymmetry; and trochlear facet asymmetry. Additional measurements included trochlear depth and lateral trochlear inclination angle. In the sagittal plane, measurements included curvilinear trochlear length, direct trochlear length, condylar height, and patellar sulcus angle. Results: Analysis of trochlear morphology using condylar height, condylar height asymmetry, and trochlear depth all increased with increasing age. The osseous and cartilaginous sulcus angles became deeper with age until age 8 and then plateaued. This corresponded with an increase in trochlear depth that also plateaued around age 8. Osseous condylar asymmetry increased with age but flipped from a larger medial condyle to a larger lateral condyle around age 8. The continued growth of the trochlea with age was further demonstrated in all measures in the sagittal view. Conclusion: This cadaveric analysis demonstrated that there is an increase in condylar height as age increased by all measurements analyzed. These changes in condylar height continued to be seen through age 11, suggesting a still-developing trochlea past this age. By age 8, a plateau in sulcus angle, and sulcus depth suggests more proportionate growth after this point. Similar changes in trochlear and patellar shape with age suggests that the 2 structures may affect each other during development. Clinical Relevance: This information can help design, develop, and determine timing of procedures that may alter the anatomy and stabilize the trochlear and patellofemoral joint.

2.
Oxid Med Cell Longev ; 2023: 5803323, 2023.
Article in English | MEDLINE | ID: mdl-37113744

ABSTRACT

The accumulation and aggregation of α-synuclein is a pathognomonic sign of Parkinson's disease (PD). Maneb (MB) exposure has also been reported as one environmental triggering factor of this multifactorial neurodegenerative disease. In our laboratory, we have previously reported that mild overexpression of α-synuclein (200% increase with respect to endogenous neuronal levels) can confer neuroprotection against several insults. Here, we tested the hypothesis that α-synuclein can modulate the neuronal response against MB-induced neurotoxicity. When exposed to MB, cells with endogenous α-synuclein expression displayed increased reactive oxygen species (ROS) associated with diminished glutamate-cysteine ligase catalytic subunit (GCLc) and hemeoxygenase-1 (HO-1) mRNA expressions and upregulation of the nuclear factor erythroid 2-related factor 2 (NRF2) repressor, BTB domain and CNC homolog 1 (BACH1). We found that α-synuclein overexpression (wt α-syn cells) attenuated MB-induced neuronal damage by reducing oxidative stress. Decreased ROS found in MB-treated wt α-syn cells was associated with unaltered GCLc and HO-1 mRNA expressions and decreased BACH1 expression. In addition, the increased SOD2 expression and catalase activity were associated with forkhead box O 3a (FOXO3a) nuclear compartmentalization. Cytoprotective effects observed in wt α-syn cells were also associated with the upregulation of silent information regulator 1 (SIRT1). In control cells, MB-treatment downregulated glutathione peroxidase 4 mRNA levels, which was coincident with increased ROS content, lipid peroxidation, and mitochondrial alterations. These deleterious effects were prevented by ferrostatin-1, an inhibitor of ferroptosis, under conditions of endogenous α-synuclein expression. The overexpression of α-synuclein attenuated MB toxicity by the activation of the same mechanisms as ferrostatin-1. Overall, our findings suggest that mild overexpression of α-synuclein attenuates MB-induced neurotoxicity through the modulation of NRF2 and FOXO3a transcription factors and prevents cell death probably by intervening in mechanisms associated with ferroptosis. Thus, we postulate that early stages of α-synuclein overexpression could be potentially neuroprotective against MB neurotoxicity.


Subject(s)
Maneb , Neurodegenerative Diseases , Neurotoxicity Syndromes , Humans , alpha-Synuclein/metabolism , Reactive Oxygen Species/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxidation-Reduction
3.
J Laryngol Otol ; 137(1): 68-75, 2023 Jan.
Article in English | MEDLINE | ID: mdl-34823621

ABSTRACT

OBJECTIVE: The role of high-resolution computed tomography scans in otosclerosis remains uncertain. There is a debate over the relationship between radiological and audiometric findings among patients. METHOD: Pre-operative audiometry and high-resolution computed tomography findings from 40 ears with surgically confirmed otosclerosis were compared. High-resolution computed tomography scan data regarding the characteristics of the disease foci, the endosteal extension and the occurrence of internal auditory canal diverticula were obtained. The influence of each radiological variable on the simple pure tone average, the high-frequency pure tone average and the bone-conduction pure tone average were investigated. RESULTS: Cases with endosteal extension (p = 0.047) and a higher number of affected sites within the otic capsule had a worse bone-conduction pure tone average, although it was only significant for the latter (p = 0.006). Those without concomitant retrofenestral disease (p = 0.019) had better simple pure tone average. CONCLUSION: The number of sites of involvement and concomitant retrofenestral disease seem to significantly impact audiometric findings in otosclerosis.


Subject(s)
Ear, Inner , Otosclerosis , Humans , Otosclerosis/complications , Otosclerosis/diagnostic imaging , Otosclerosis/epidemiology , Audiometry, Pure-Tone/methods , Retrospective Studies , Tomography, X-Ray Computed/methods
4.
PLoS One ; 15(9): e0238115, 2020.
Article in English | MEDLINE | ID: mdl-32915812

ABSTRACT

This work provides an in-depth computational performance study of the parallel finite-difference time-domain (FDTD) method. The parallelization is done at various levels including: shared- (OpenMP) and distributed- (MPI) memory paradigms and vectorization on three different architectures: Intel's Knights Landing, Skylake and ARM's Cavium ThunderX2. This study contributes to prove, in a systematic manner, the well-established claim within the Computational Electromagnetic community, that the main factor limiting FDTD performance, in realistic problems, is the memory bandwidth. Consequently a memory bandwidth threshold can be assessed depending on the problem size in order to attain optimal performance. Finally, the results of this study have been used to optimize the workload balancing of simulation of a bioelectromagnetic problem consisting in the exposure of a human model to a reverberation chamber-like environment.


Subject(s)
Algorithms , Electromagnetic Fields , Bone and Bones/physiology , Computer Storage Devices , Computer Systems , Humans , Kidney/physiology , Liver/physiology , Models, Theoretical , Software
5.
Phys Rev E ; 101(6-1): 063305, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32688467

ABSTRACT

In this work, we use the finite differences in time domain (FDTD) numerical method to compute and assess the validity of Hopf solutions, or hopfions, for the electromagnetic field equations. In these solutions, field lines form closed loops characterized by different knot topologies which are preserved during their time evolution. Hopfions have been studied extensively in the past from an analytical perspective but never, to the best of our knowledge, from a numerical approach. The implementation and validation of this technique eases the study of more complex cases of this phenomena; e.g., how these fields could interact with materials (e.g., anisotropic or nonlinear), their coupling with other physical systems (e.g., plasmas), and also opens the path on their artificial generation by different means (e.g., antenna arrays or lasers).

7.
Sci Rep ; 10(1): 7628, 2020 05 06.
Article in English | MEDLINE | ID: mdl-32376984

ABSTRACT

Endothelial dysfunction is a characteristic of systemic arterial hypertension (SAH) and an early marker of atherosclerosis. Aerobic exercise training (AT) improves endothelial function. However, the effects of resistance training (RT) and combined training (CT) on endothelial function remain controversial in individuals with SAH. We determined the effects of AT, RT, and CT on endothelial function and systolic (SBP)/diastolic blood pressure (DBP) in individuals with prehypertension or hypertension. Forty-two participants (54 ± 11 y, resting SBP/DBP 137 ± 9/86 ± 6 mmHg) were randomly allocated into AT (n = 14, 40 min of cycling, 50-75% heart rate reserve), RT (n = 14, 6 resistance exercises, 4 × 12 repetitions, 60% maximum strength) and CT (n = 14, 2 × 12 repetitions of RT + 20 min of AT). All participants performed a 40-minute exercise session twice a week for 8 weeks. Endothelial function was evaluated by brachial artery flow-mediated dilation (FMD). Blood pressure was evaluated through ambulatory monitoring for 24 hours. After 8 weeks of exercise training, blood pressure was reduced in all 3 groups: -5.1 mmHg in SBP (95%CI -10.1, 0.0; p = 0.003) in AT; -4.0 mmHg in SBP (95%CI -7.8, -0.5; p = 0.027) in RT; and -3.2 mmHg in DBP (95%CI -7.9, 1.5; p = 0.001) in CT. All 3 exercise training modalities produced similar improvements in FMD: + 3.2% (95%CI 1.7, 4.6) (p < 0.001) in AT; + 4.0% (95%CI 2.1, 5.7) (p < 0.001) in RT; and +6.8% (95%CI 2.6, 11.1) (p = 0.006) in CT. In conclusion, different exercise training modalities were similarly effective in improving endothelial function but impacts on ambulatory blood pressure appear to be variable in individuals with prehypertension or hypertension.


Subject(s)
Blood Pressure , Endothelium, Vascular/pathology , Exercise , Hypertension/pathology , Hypertension/physiopathology , Prehypertension/pathology , Prehypertension/physiopathology , Female , Humans , Male , Middle Aged , Resistance Training
8.
Free Radic Biol Med ; 155: 1-9, 2020 08 01.
Article in English | MEDLINE | ID: mdl-32416241

ABSTRACT

Zinc plays a key role in the modulation of neuronal redox homeostasis. A decreased zinc availability is associated with neuronal NADPH oxidase and nitric oxide synthase activation, deregulation of redox signaling, and impaired glutathione synthesis. The present work tested the hypothesis that zinc is necessary in the neuronal defense response against dopamine (DA)-induced oxidative stress, in particular through heme oxygenase-1 (HO-1) upregulation. DA showed higher cytotoxicity when zinc availability was low. Human IMR-32 neuroblastoma cells responded to high DA concentrations (100 µM) by upregulating HO-1. This upregulation involved Nrf2 translocation to the nucleus, degradation of the Bach-1 repressor, and Nrf2-DNA binding, but it was independent of ERK1/2 activation. DA-mediated induction of HO-1 expression was dependent on the concentration of zinc in the medium. IMR-32 cells incubated in zinc deficient medium showed an impaired response to DA, with lower HO-1 mRNA and protein levels than control DA-challenged cells. This altered HO-1 upregulation was reversed by zinc supplementation. In the presence of DA, Nrf2 nuclear translocation and Bach-1 degradation were lower in zinc deficient cells. The mechanisms involved include: i) impaired Nrf2-tubulin interactions and ii) alterations in the proteasome-mediated degradation of Bach-1 secondary to a decreased ubiquitylation. Results suggest that zinc is crucial in the neuronal response to DA-induced oxidative stress in part through its role in the modulation of the Nrf2-and Bach-1-driven upregulation of HO-1 expression.


Subject(s)
NF-E2-Related Factor 2 , Neuroblastoma , Heme Oxygenase-1/genetics , Heme Oxygenase-1/metabolism , Humans , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Neuroblastoma/genetics , Oxidative Stress , Zinc
9.
Sensors (Basel) ; 19(15)2019 Jul 27.
Article in English | MEDLINE | ID: mdl-31357583

ABSTRACT

Industry 4.0 is a synonym for the confluence of technologies that allows the integration of information technology, data science, and automated equipment, to produce smart industrial systems. The process of inserting new technologies into current conventional environments involves a wide range of disciplines and approaches. This article presents the process that was followed to identify and upgrade one station in an industrial workshop to make it compatible with the more extensive system as it evolves into the Industry 4.0 environment. An information processing kit was developed to upgrade the equipment from an automated machine to an Industry 4.0 station. The kit includes a structure to support the sensor and the data processing unit; this unit consisted of a minicomputer that records the data, graded the performance of the components, and sent the data to the cloud for storage, reporting, and further analysis. The information processing kit allowed the monitoring of the inspection system and improved the quality and speed of the inspection process.

10.
Phys Chem Chem Phys ; 19(42): 28781-28787, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-29048084

ABSTRACT

Manganese oxides (MnxOy) are considered as a promising catalyst alternative to platinum in fuel cell applications. In fact, a proper catalyst is needed in order to facilitate the oxygen reduction reaction (ORR) at the cathode, and platinum is considered the best material due to its low overpotential for this reaction. Contrary to platinum, MnxOy is inexpensive, environmentally friendly and can be shaped into several nanostructures; furthermore, most of them show significant electro-catalytic performance. Several strategies have been carried out in order to increase their efficiency, by preparing light and high-surface area materials. In this framework, nanofibres are among the most promising nanostructures that can be used for this purpose. In this work, a study of the thermal, morphological and catalytic behavior of MnxOy nanofibres obtained through the electrospinning technique is proposed. Emphasis is given to the thermal evolution of the precursors, proposing a possible crystallization mechanism of the different manganese oxides obtained. It turns out that manganese oxide nanofibres exhibit good catalytic performance for the ORR, comparable to those obtained by using Pt-based catalysts.

11.
Org Biomol Chem ; 15(14): 2953-2961, 2017 Apr 05.
Article in English | MEDLINE | ID: mdl-28291271

ABSTRACT

A homo-chiral synthesis of (7R,8aS)-octahydro-5,5-dimethylindolizin-7-amine 8 and (7S, 8aS)-octahydro-5,5-dimethylindolizin-7-ol 9, amine building blocks which have found applications within the pharmaceutical industry, is presented. The approach uses a Novozym 435-mediated kinetic resolution of racemic octahydroindolizine (indolizidine) alcohol 13 as a key step (up to 100 g scale).


Subject(s)
Alcohols/chemistry , Indolizidines/chemistry , Indolizidines/chemical synthesis , Lipase/metabolism , Biocatalysis , Chemistry Techniques, Synthetic , Enzymes, Immobilized , Fungal Proteins , Kinetics , Models, Molecular , Molecular Conformation , Stereoisomerism
12.
Eur J Clin Microbiol Infect Dis ; 35(11): 1803-1810, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27477855

ABSTRACT

Cryptococcosis, caused by Cryptococcus gattii sensu lato, is an emerging disease that was initially found in (sub)tropical regions but recently expanded to temperate regions. Cryptococcus gattii s.l. infections are mostly encountered in healthy individuals, frequently affecting both lungs and the central nervous system (CNS). Usually, C. gattii s.l. is less susceptible to antifungal compounds than its counterpart, C. neoformans s.l. We studied 18 clinical C. gattii s.l. isolates with amplified fragment length polymorphism (AFLP) fingerprinting, mating-typing, multi-locus sequence typing (MLST) and antifungal susceptibility testing. All isolates were C. deuterogattii (genotype AFLP6/VGII), 14 were mating-type α and four were type a. Amphotericin B, itraconazole, voriconazole, posaconazole and isavuconazole showed high activity, with minimum inhibitory concentration (MIC) ranges of 0.063-0.25, 0.031-0.25, 0.031-0.25, 0.031-0.25 and <0.016-0.25 µg mL-1, respectively. Fluconazole and flucytosine had high geometric mean MICs of 2.07 and 3.7 µg mL-1, respectively. Most cases occurred in immunocompetent patients (n = 10; 55.6 %) and CNS involvement was the most common clinical presentation (n = 14; 77.8 %). Three patients (16.7 %) showed sequelae, hyperreflexia, dysarthria, diadochokinesia, anosmia and upper limb weakness. In conclusion, all infections were caused by C. deuterogattii (AFLP6/VGII) and the majority of patients were immunocompetent, with the CNS as the most affected site. All antifungal drugs had high in vitro activity against C. deuterogattii isolates, except fluconazole and flucytosine.


Subject(s)
Antifungal Agents/pharmacology , Cryptococcosis/microbiology , Cryptococcus gattii/classification , Cryptococcus gattii/drug effects , Drug Resistance, Fungal , Amplified Fragment Length Polymorphism Analysis , Brazil/epidemiology , Cryptococcosis/epidemiology , Cryptococcus gattii/genetics , Cryptococcus gattii/isolation & purification , DNA Fingerprinting , Female , Genes, Mating Type, Fungal , Genotype , Humans , Male , Microbial Sensitivity Tests , Multilocus Sequence Typing
13.
Exp Eye Res ; 113: 172-81, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23791636

ABSTRACT

Iron accumulation and oxidative stress are hallmarks of retinas from patients with age-related macular degeneration (AMD). We have previously demonstrated that iron-overloaded retinas are a good in vitro model for the study of retinal degeneration during iron-induced oxidative stress. In this model we have previously characterized the role of cytosolic phospholipase A2 (cPLA2) and calcium-independent isoform (iPLA2). The aim of the present study was to analyze the implications of Group V secretory PLA2 (sPLA2), another member of PLA2 family, in cyclooxygenase (COX)-2 and nuclear factor kappa B (NF-κB) regulation. We found that sPLA2 is localized in cytosolic fraction in an iron concentration-dependent manner. By immunoprecipitation (IP) assays we also demonstrated an increased association between Group V sPLA2 and COX-2 in retinas exposed to iron overload. However, COX-2 activity in IP assays was observed to decrease in spite of the increased protein levels observed. p65 (RelA) NF-κB levels were increased in nuclear fractions from retinas exposed to iron. In the presence of ATK (cPLA2 inhibitor) and YM 26734 (sPLA2 inhibitor), the nuclear localization of both p65 and p50 NF-κB subunits was restored to control levels in retinas exposed to iron-induced oxidative stress. Membrane repair mechanisms were also analyzed by studying the participation of acyltransferases in phospholipid remodeling during retinal oxidation stress. Acidic phospholipids, such as phosphatidylinositol (PI) and phosphatidylserine (PS), were observed to show an inhibited acylation profile in retinas exposed to iron while phosphatidylethanolamine (PE) showed the opposite. The use of PLA2 inhibitors demonstrated that PS is actively deacylated during iron-induced oxidative stress. Results from the present study suggest that Group V sPLA2 has multiple intracellular targets during iron-induced retinal degeneration and that the specific role of sPLA2 could be related to inflammatory responses by its participation in NF-κB and COX-2 regulation.


Subject(s)
Cyclooxygenase 2/metabolism , Group V Phospholipases A2/physiology , Macular Degeneration/metabolism , NF-kappa B/metabolism , Oxidative Stress/drug effects , Retina/drug effects , Acetylation , Acetyltransferases/metabolism , Animals , Blotting, Western , Cattle , Cytosol/metabolism , Electrophoresis, Polyacrylamide Gel , Enzyme Inhibitors/pharmacology , Ferrous Compounds/toxicity , Group V Phospholipases A2/antagonists & inhibitors , Iron Overload/metabolism , Phosphatidylethanolamines/metabolism , Phosphatidylinositols/metabolism , Phosphatidylserines/metabolism , Phospholipases A/metabolism , Phospholipases A/physiology , Retina/metabolism
14.
Neurochem Int ; 61(5): 749-58, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22732705

ABSTRACT

Both elevated iron concentrations and the resulting oxidative stress condition are common signs in retinas of patients with age-related macular degeneration (AMD). The role of phospholipase A(2) (PLA(2)) during iron-induced retinal toxicity was investigated. To this end, isolated retinas were exposed to increasing Fe(2+) concentrations (25, 200 or 800 µM) or to the vehicle, and lipid peroxidation levels, mitochondrial function, and the activities of cytosolic PLA(2) (cPLA(2)) and calcium-independent PLA(2) (iPLA(2)) were studied. Incubation with Fe(2+) led to a time- and concentration-dependent increase in retinal lipid peroxidation levels whereas retinal cell viability was only affected after 60 min of oxidative injury. A differential release of arachidonic acid (AA) and palmitic acid (PAL) catalyzed by cPLA(2) and iPLA(2) activities, respectively, was also observed in microsomal and cytosolic fractions obtained from retinas incubated with iron. AA release diminished as the association of cyclooxygenase-2 increased in microsomes from retinas exposed to iron. Retinal lipid peroxidation and cell viability were also analyzed in the presence of cPLA(2) inhibitor, arachidonoyl trifluoromethyl ketone (ATK), and in the presence of iPLA(2) inhibitor, bromoenol lactone (BEL). ATK decreased lipid peroxidation levels and also ERK1/2 activation without affecting cell viability. BEL showed the opposite effect on lipid peroxidation. Our results demonstrate that iPLA(2) and cPLA(2) are differentially regulated and that they selectively participate in retinal signaling in an experimental model resembling AMD.


Subject(s)
Ferrous Compounds/toxicity , Macular Degeneration/chemically induced , Macular Degeneration/enzymology , Phospholipases A2/metabolism , Retina/enzymology , Animals , Cattle , Isoenzymes/metabolism , Isoenzymes/physiology , Lipid Peroxidation/drug effects , Lipid Peroxidation/physiology , Organ Culture Techniques , Phospholipases A2/physiology
15.
Neotrop Entomol ; 40(1): 89-96, 2011.
Article in English | MEDLINE | ID: mdl-21437488

ABSTRACT

Ovary development and maturation of Nezara viridula (L.) were evaluated by examining ovariole morphology and the alterations in the biochemical (protein synthesis related to reproduction) composition of the hemolymph. Quantitative and qualitative protein analyses were performed and ovary structural alterations for the pre-reproductive and reproductive stages were recorded. Total concentration of proteins in female hemolymph gradually increased until the end of the pre-mating stage, remaining unaltered thereafter. Proteins linked to reproduction (vitellogenins) appeared in the hemolymph 10 days after adult emergence and indicated the end of the pre-mating stage. After mating, total protein concentration in the hemolymph was lower compared to virgin females; vitellogenin levels were similar during most of the observation period. Oocyte development and maturation were gradual and age dependent. Ten-day-old females had chorionated oocytes ready for fertilization. Mating did not stimulate oocyte development in N. viridula, but the lack of mating activity appeared to have stimulated oocyte resorption in 17-day-old females.


Subject(s)
Hemiptera/growth & development , Ovary/growth & development , Age Factors , Animals , Female , Sexual Maturation
16.
Neotrop. entomol ; 40(1): 89-96, Jan.-Feb. 2011. ilus, graf
Article in English | LILACS | ID: lil-578839

ABSTRACT

Ovary development and maturation of Nezara viridula (L.) were evaluated by examining ovariole morphology and the alterations in the biochemical (protein synthesis related to reproduction) composition of the hemolymph. Quantitative and qualitative protein analyses were performed and ovary structural alterations for the pre-reproductive and reproductive stages were recorded. Total concentration of proteins in female hemolymph gradually increased until the end of the pre-mating stage, remaining unaltered thereafter. Proteins linked to reproduction (vitellogenins) appeared in the hemolymph 10 days after adult emergence and indicated the end of the pre-mating stage. After mating, total protein concentration in the hemolymph was lower compared to virgin females; vitellogenin levels were similar during most of the observation period. Oocyte development and maturation were gradual and age dependent. Ten-day-old females had chorionated oocytes ready for fertilization. Mating did not stimulate oocyte development in N. viridula, but the lack of mating activity appeared to have stimulated oocyte resorption in 17-day-old females.


Subject(s)
Animals , Female , Hemiptera/growth & development , Ovary/growth & development , Age Factors , Sexual Maturation
17.
Psicol. reflex. crit ; 24(1): 180-185, 2011. tab
Article in Portuguese | Index Psychology - journals | ID: psi-50148

ABSTRACT

A estratégia de auto-instruções tem vindo a ser reconhecida como uma relevante forma de regulação cognitivo-comportamental no incremento das capacidades atencionais, nomeadamente em sujeitos com Transtorno do Deficit de Atenção com Hiperatividade (TDAH). Neste artigo foi avaliada a atenção seletiva e a atenção sustentada em 2 grupos, ambos formados por pessoas com e sem TDAH, sendo que a um deles foi solicitada a realização de auto-instrução, com o objetivo de verificar se o uso desta estratégia promove as capacidades da atenção. Os resultados demonstraram que os sujeitos que realizam a estratégia de auto-instruções, quer apresentem ou não TDAH, manifestam melhores resultados do que os sujeitos que não a realizaram.(AU)


Self-instruction strategy has been recognized as a relevant strategy in cognitive and behavioural regulation as a way of improving attention skills, namely in subjects with Attention Deficit Hyperactivity Disorder (ADHD). This paper aims at demonstrating the effectiveness of this strategy regarding this disorder in subjects with and without ADHD as a mean of promoting attention skills, particularly selective and sustained attention. The results showed that subjects who performed the verbal self-instruction strategy presented better results in both attention processes assessed, than those who did not do it.(AU)


Subject(s)
Humans , Male , Female , Child , Adolescent , Attention Deficit Disorder with Hyperactivity/psychology , Health Strategies , Attention , Programmed Instructions as Topic
18.
Psicol. reflex. crit ; 24(1): 180-185, 2011. tab
Article in Portuguese | LILACS | ID: lil-596097

ABSTRACT

A estratégia de auto-instruções tem vindo a ser reconhecida como uma relevante forma de regulação cognitivo-comportamental no incremento das capacidades atencionais, nomeadamente em sujeitos com Transtorno do Deficit de Atenção com Hiperatividade (TDAH). Neste artigo foi avaliada a atenção seletiva e a atenção sustentada em 2 grupos, ambos formados por pessoas com e sem TDAH, sendo que a um deles foi solicitada a realização de auto-instrução, com o objetivo de verificar se o uso desta estratégia promove as capacidades da atenção. Os resultados demonstraram que os sujeitos que realizam a estratégia de auto-instruções, quer apresentem ou não TDAH, manifestam melhores resultados do que os sujeitos que não a realizaram.


Self-instruction strategy has been recognized as a relevant strategy in cognitive and behavioural regulation as a way of improving attention skills, namely in subjects with Attention Deficit Hyperactivity Disorder (ADHD). This paper aims at demonstrating the effectiveness of this strategy regarding this disorder in subjects with and without ADHD as a mean of promoting attention skills, particularly selective and sustained attention. The results showed that subjects who performed the verbal self-instruction strategy presented better results in both attention processes assessed, than those who did not do it.


Subject(s)
Humans , Male , Female , Child , Adolescent , Attention , Health Strategies , Attention Deficit Disorder with Hyperactivity/psychology , Programmed Instructions as Topic
19.
Neuroscience ; 170(2): 381-9, 2010 Oct 13.
Article in English | MEDLINE | ID: mdl-20674685

ABSTRACT

The amyloid beta-peptide (Abeta), which is thought to be the major cause of Alzheimer's disease (AD), is known to be capable of aggregating in different states: soluble monomers and oligomers, and insoluble aggregates. The Abeta aggregation state as well as its toxicity has been related to the interaction between the peptide and transition metals such as iron and copper. However, this relationship, as well as the effects of Abeta on the synaptic endings, is not fully understood. The aggregation states of Abeta in the presence of iron and copper, as well as their effects on synaptic viability and signaling were investigated in this work. During acute incubation treatments (5 min-4 h), Abeta/metal impaired mitochondrial function to the same extent as has been observed with the metal alone. However, in the presence of Abeta/iron (10 and 50 muM), plasma membrane integrity was disrupted to a greater extent than when generated by either iron or Abeta alone, indicating that the membrane constitutes the first target of synaptic injury. Akt activation by Abeta/iron was evident after 5 min of incubation and was higher than that observed in the presence of the metal alone. This activation was barely detected after 4 h of incubation, demonstrating that there is no correlation between the extent of synaptic damage and the activation of this kinase. Extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation profile was different from that observed for Akt. Accordingly, the presence of Abeta/metal could differentially modulate the activity of these kinases. This work shows evidence of the initial events locally triggered at the synapse by Abeta and transition metals. As synapses have been proposed as the starting point of Abeta/metal-triggered events, the characterization of early mechanisms occurring in models that mimic AD could be important for the search of unexplored therapeutics tools.


Subject(s)
Amyloid beta-Peptides/pharmacology , Cell Survival/drug effects , Copper/pharmacology , Iron/pharmacology , Synaptosomes/drug effects , Transition Elements/pharmacology , Amyloid beta-Peptides/chemistry , Animals , Cell Membrane/drug effects , Copper/chemistry , Drug Interactions , Extracellular Signal-Regulated MAP Kinases/metabolism , Iron/chemistry , L-Lactate Dehydrogenase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Wistar , Signal Transduction/drug effects , Transition Elements/chemistry
20.
Biochim Biophys Acta ; 1798(3): 624-36, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20026046

ABSTRACT

Detergent-resistant membranes (DRMs) are a class of specialized microdomains that compartmentalize several signal transduction processes. In this work, DRMs were isolated from cerebral cortex synaptic endings (Syn) on the basis of their relative insolubility in cold Triton X-100 (1%). The lipid composition and marker protein content were analyzed in DRMs obtained from adult and aged animals. Both DRM preparations were enriched in Caveolin, Flotillin-1 and c-Src and also presented significantly higher sphingomyelin (SM) and cholesterol content than purified Syn. Total phospholipid-fatty acid composition presented an increase in 16:0 (35%), and a decrease in 20:4n-6 (67%) and 22:6n-3 (68%) content in DRM from adults when compared to entire synaptic endings. A more dramatic decrease was observed in the 20:4n-6 and 22:6n-3 content in DRMs from aged animals (80%) with respect to the results found in adults. The coexistence of phosphatidylcholine-specific-phospholipase C (PC-PLC) and phospholipase D (PLD) in Syn was previously reported. The presence of these signaling pathways was also investigated in DRMs isolated from adult and aged rats. Both PC-PLC and PLD pathways generate the lipid messenger diacylglycerol (DAG) by catalyzing PC hydrolysis. PC-PLC and PLD1 localization were increased in the DRM fraction. The increase in DAG generation (60%) in the presence of ethanol, confirmed that PC-PLC was also activated when compartmentalized in DRMs. Conversely, PLD2 was excluded from the DRM fraction. Our results show an age-related differential fatty acid composition and a selective localization of PC-derived signaling in synaptic DRMs obtained from adult and aged rats.


Subject(s)
Detergents/pharmacology , Phosphatidylcholines/metabolism , Signal Transduction/drug effects , Synapses/drug effects , Synapses/metabolism , Aging/metabolism , Animals , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Diglycerides/metabolism , Fatty Acids/metabolism , Membranes/drug effects , Membranes/enzymology , Rats , Rats, Wistar , Synapses/enzymology , Type C Phospholipases/metabolism
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