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1.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772717

RESUMO

The Qui-Bot H2O project involves developing four educational sustainable robots and their associated software. Robots are equipped with HRI features such as voice recognition and color sensing, and they possess a humanoid appearance. The project highlights the social and ethical aspects of robotics applied to chemistry and industry 4.0 at an early age. Here, we report the results of an interactive study that involved 212 students aged within the range of 3-18. Our educational robots were used to measure the backgrounds, impact, and interest of students, as well as their satisfaction after interacting with them. Additionally, we provide an ethical study of the use of these robots in the classroom and a comparison of the interactions of humanoid versus non-humanoid educational robots observed in early childhood learning. Our findings demonstrate that these robots are useful in teaching technical and scientific concepts in a playful and intuitive manner, as well as in increasing the number of girls who are interested in science and engineering careers. In addition, major impact measures generated by the project within a year of its implementation were analyzed. Several public administrations in the area of gender equality endorsed and participated in the Qui-Bot H2O project in addition to educational and business entities.


Assuntos
Robótica , Pré-Escolar , Feminino , Humanos , Robótica/educação , Criança , Adolescente
2.
New Phytol ; 234(2): 735-747, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35090193

RESUMO

The plant area index (PAI) is a structural trait that succinctly parametrizes the foliage distribution of a canopy and is usually estimated using indirect optical techniques such as digital hemispherical photography. Critically, on-the-ground photographic measurements forgo the vertical variation of canopy structure which regulates the local light environment. Hence new approaches are sought for vertical sampling of traits. We present an uncrewed aircraft system (UAS) spherical photographic method to obtain structural traits throughout the depth of tree canopies. Our method explained 89% of the variation in PAI when compared with ground-based hemispherical photography. When comparing UAS vertical trait profiles with airborne laser scanning data, we found highest agreement in an open birch (Betula pendula/pubescens) canopy. Minor disagreement was found in dense spruce (Picea abies) stands, especially in the lower canopy. Our new method enables easy estimation of the vertical dimension of canopy structural traits in previously inaccessible spaces. The method is affordable and safe and therefore readily usable by plant scientists.


Assuntos
Picea , Folhas de Planta , Aeronaves , Fotografação , Folhas de Planta/fisiologia , Árvores/fisiologia
3.
Soft comput ; 23(7): 2177-2186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30956543

RESUMO

This paper is a contribution to graded model theory, in the context of mathematical fuzzy logic. We study characterizations of classes of graded structures in terms of the syntactic form of their first-order axiomatization. We focus on classes given by universal and universal-existential sentences. In particular, we prove two amalgamation results using the technique of diagrams in the setting of structures valued on a finite MTL-algebra, from which analogues of the Los-Tarski and the Chang-Los-Suszko preservation theorems follow.

4.
Free Radic Biol Med ; 143: 16-24, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351175

RESUMO

Proteolytic enzymes are often strongly affected by redox reactions, free radicals, oxidation, or oxidative stress. The 20S Proteasome and the Immuno-Proteasome are examples of major intracellular proteases whose concentration, transcription, translation, and proteolytic activity are all subject to redox regulation. Proteasomes are essential in maintaining overall protein homeostasis (or proteostasis), and their dysregulation results in detrimental phenotypes associated with various pathologies, including several common age-related diseases. Many studies have used Western blots to assess redox changes in Proteasome protein levels or RT-PCR to study RNA transcript levels, but actual measurements of proteolytic activity are far less common. Since each intact protein substrate exhibits a different proteolytic profile when incubated with proteasome or Immuno-Proteasome [± activators such as 19S or 11S (also called PA28)] and these proteolytic profiles are drastically altered if the protein substrate is denatured, for example by oxidation, heat, acetylation, or methylation. In an attempt to standardize proteasomal activity measurements small fluorogenic protein/peptide substrates were developed to test the three proteolytically active sites of the Proteasome and Immuno-Proteasome: trypsin-like, chymotrypsin-like, and caspase-like activities. Despite extensive use of fluorogenic peptide substrates to measure proteasome activity, there is an absence of a standardized set of best practices. In this study we analyze different parameters, such as sample concentration, AMC conjugated substrate concentration, duration of assay, and frequency of measurements, and examine how they impact the determination of Proteasome and Immuno-Proteasome activities using fluorogenic peptide substrates.


Assuntos
Oxirredução , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Acetilcisteína/análogos & derivados , Acetilcisteína/química , Animais , Anti-Inflamatórios/farmacologia , Quimotripsina/química , Citoplasma/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Estresse Oxidativo , Oxigênio/metabolismo , Fenótipo , Tripsina/química
5.
Free Radic Res ; 52(7): 737-750, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29742940

RESUMO

Anxiety disorders are the most common mental illness in the USA affecting 18% of the population. The cause(s) of anxiety disorders is/are not completely clear, and research in the neurobiology of anxiety at the molecular level is still rather limited. Although mounting clinical and preclinical evidence now indicates that oxidative stress may be a major component of anxiety pathology, whether oxidative stress is the cause or consequence remains elusive. Studies conducted over the past few years suggest that anxiety disorders may be characterised by lowered antioxidant defences and increased oxidative damage to proteins, lipids, and nucleic acids. In particular, oxidative modifications to proteins have actually been proposed as a potential factor in the onset and progression of several psychiatric disorders, including anxiety and depressive disorders. Oxidised proteins are normally degraded by the proteasome proteolytic complex in the cell cytoplasm, nucleus, and endoplasmic reticulum. The Lon protease performs a similar protective function inside mitochondria. Impairment of the proteasome and/or the Lon protease results in the accumulation of toxic oxidised proteins in the brain, which can cause severe neuronal trauma. Recent evidence points to possible proteolytic dysfunction and accumulation of damaged, oxidised proteins as factors that may determine the appearance and severity of psychotic symptoms in mood disorders. Thus, critical interactions between oxidative stress, proteasome, and the Lon protease may provide keys to the molecular mechanisms involved in emotional regulation, and may also be of great help in designing and screening novel anxiolytics and antidepressants.


Assuntos
Transtornos de Ansiedade/etiologia , Estresse Oxidativo , Animais , Transtornos de Ansiedade/fisiopatologia , Humanos
6.
Antioxid Redox Signal ; 25(16): 886-901, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27392670

RESUMO

SIGNIFICANCE: Alzheimer's disease is a neurodegenerative disorder that is projected to exceed more than 100 million cases worldwide by 2050. Aging is considered the primary risk factor for some 90% of Alzheimer's cases but a significant 10% of patients suffer from aggressive, early-onset forms of the disease. There is currently no effective Alzheimer's treatment and this, coupled with a growing aging population, highlights the necessity to understand the mechanism(s) of disease initiation and propagation. A major hallmark of Alzheimer's disease pathology is the accumulation of amyloid-ß (Aß) aggregates (an early marker of Alzheimer's disease), and neurofibrillary tangles, comprising the hyper-phosphorylated microtubule-associated protein Tau. Recent Advances: Protein oxidation is frequently invoked as a potential factor in the progression of Alzheimer's disease; however, whether it is a cause or a consequence of the pathology is still being debated. The Proteasome complex is a major regulator of intracellular protein quality control and an essential proteolytic enzyme for the processing of both Aß and Tau. Recent studies have indicated that both protein oxidation and excessive phosphorylation may limit Proteasomal processing of Aß and Tau in Alzheimer's disease. CRITICAL ISSUES: Thus, the Proteasome may be a key factor in understanding the development of Alzheimer's disease pathology; however, its significance is still very much under investigation. FUTURE DIRECTIONS: Discovering how the proteasome is affected, regulated, or dysregulated in Alzheimer's disease could be a valuable tool in the efforts to understand and, ultimately, eradicate the disease. Antioxid. Redox Signal. 25, 886-901.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Estresse Oxidativo , Complexo de Endopeptidases do Proteassoma/metabolismo , Envelhecimento/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Humanos , Mitocôndrias/metabolismo , Oxirredução , Fosforilação , Protease La/metabolismo , Proteólise , Proteínas tau/metabolismo
7.
J Alzheimers Dis ; 51(3): 701-11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26890773

RESUMO

Amyloid-ß (Aß) clearance from brain, which is decreased in Alzheimer's disease, is facilitated by apolipoprotein E (ApoE). ApoE is upregulated by activation of the retinoid X receptor moiety of the RXR/PPARγ dimeric receptor. Genistein, a non-toxic, well-tested, and inexpensive drug activates the other moiety of the receptor PPARγ. Treatment of an Alzheimer's disease mouse model with genistein results in a remarkable and rapid improvement in various parameters of cognition, such as hippocampal learning, recognition memory, implicit memory, and odor discrimination. This is associated with a lowering of Aß levels in brain, in the number and the area of amyloid plaques (confirmed in vivo by positron emission tomography) as well as in microglial reactivity. Finally, incubation of primary astrocytes with genistein results in a PPARγ-mediated increased release of ApoE. Our results strongly suggest that controlled clinical trials should be performed to test the effect of genistein as treatment of human Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas E/metabolismo , Genisteína/farmacologia , Nootrópicos/farmacologia , PPAR gama/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Aprendizagem da Esquiva/efeitos dos fármacos , Bexaroteno , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Habituação Psicofisiológica/efeitos dos fármacos , Aprendizagem em Labirinto , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Percepção Olfatória/efeitos dos fármacos , Placa Amiloide/diagnóstico por imagem , Placa Amiloide/tratamento farmacológico , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Reconhecimento Psicológico/efeitos dos fármacos , Tetra-Hidronaftalenos/farmacologia
8.
Biomed Res Int ; 2014: 580852, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24812624

RESUMO

INTRODUCTION: Antioxidant properties of resveratrol have been intensively studied for the last years, both in vivo and in vitro. Its bioavailability after an oral dose is very low and therefore it is very important to make sure that plasma concentrations of free resveratrol are sufficient enough to be active as antioxidant. AIMS: In the present study, using nutritionally relevant concentrations of resveratrol, we aim to confirm its antioxidant capacity on reducing peroxide levels and look for the molecular pathway involved in this antioxidant effect. METHODS: We used mammary gland tumor cells (MCF-7), which were pretreated with different concentrations of resveratrol for 48 h, and/or a PTEN inhibitor (bpV: bipy). Hydrogen peroxide levels were determined by fluorimetry, PTEN levels and Akt phosphorylation by Western Blotting, and mRNA expression of antioxidant genes by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Resveratrol treatment for 48 h lowered peroxide levels in MCF-7, even at low nutritional concentrations (1 nM). This effect was mediated by the activation of PTEN/Akt pathway, which resulted in an upregulation of catalase and MnSOD mRNA levels. CONCLUSION: Resveratrol acts as an antioxidant at nutritionally relevant concentrations by inducing the expression of antioxidant enzymes, through a mechanism involving PTEN/Akt signaling pathway.


Assuntos
Antioxidantes/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Estilbenos/farmacologia , Catalase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Células MCF-7 , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
9.
Antioxid Redox Signal ; 20(2): 236-46, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23725100

RESUMO

AIMS: The usefulness of estrogen replacement therapy (ERT) in preventing oxidative stress associated with menopause is controversial. We aimed to study if there is a critical time window for effective treatment of the effects of ovariectomy with estrogens at the molecular, metabolic, and cellular level. RESULTS: Our main finding is that early, but not late onset of ERT prevents an ovariectomy-associated increase in mitochondrial hydrogen peroxide levels, oxidative damage to lipids and proteins, and a decrease in glutathione peroxidase and catalase activity in rats. This may be due to a change in the estrogen receptor (ER) expression profile: ovariectomy increases the ER α/ß ratio and immediate estrogen replacement prevents it. Positron emission tomography analysis shows that ovariectomy decreases the brain glucose uptake in vivo and that estrogen administration is beneficial, but only if administered immediately after deprivation. Ovariectomy decreases GLUT-1 and 3 glucose transporters in the brain, and only early onset estrogen administration prevents it. Plasma from rats treated with estrogens immediately after ovariectomy show similar metabolomics profiles as controls. INNOVATION: We provide molecular basis for the recommendation of early onset ERT and explain its lack of effectiveness if a significant time period elapses after ovariectomy and probably after the onset of menopause. CONCLUSION: Only early, but not late onset administration of estrogens after ovariectomy has beneficial effects at molecular levels on oxidative stress, brain glucose uptake, and metabolomic profiles.


Assuntos
Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Ovariectomia , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Peróxido de Hidrogênio/metabolismo , Metabolômica , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Ratos
10.
Psychoneuroendocrinology ; 45: 154-66, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24845186

RESUMO

Postmenopausal women may be more vulnerable to cognitive loss and Alzheimer's disease (AD) than premenopausal women because of their deficiency in estrogens, in addition to their usually older age. Aerobic physical exercise has been proposed as a therapeutic approach for maintaining health and well-being in postmenopausal women, and for improving brain health and plasticity in populations at high risk for AD. To study the neuroprotective mechanisms of physical exercise in a postmenopausal animal model, we submitted previously ovariectomized, six-month old non-transgenic and 3xTg-AD mice to three months of voluntary exercise in a running wheel. At nine months of age, we observed lower grip strength and some exacerbation of the behavioral and psychological symptoms of dementia (BPSD)-like involving active exploratory activities. A similar major cognitive impairment was observed of ovariectomized 3xTg-AD mice in comparison with sham-operated 3xTg-AD mice. A reduction of bodily fitness and lack of retention of memory were observed in the ovariectomized non-transgenic mice. Physical exercise protected against all deleterious behaviors and normalized learning and memory. It also protected against body frailty, as expected. Analyses of hippocampal key markers of antioxidant and neuroplasticity signaling pathways, showed that ovariectomy impairs the activation of CREB through physical exercise. Furthermore, molecular and behavioral correlates suggested a central role of BDNF in the neuroprotection mediated by physical exercise therapy against apathy and memory loss induced by ovariectomy and the AD-genotype.


Assuntos
Doença de Alzheimer , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Citoproteção , Neurônios/fisiologia , Condicionamento Físico Animal/fisiologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Precursor de Proteína beta-Amiloide/genética , Animais , Cognição/fisiologia , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fármacos Neuroprotetores , Ovariectomia , Condicionamento Físico Animal/psicologia , Presenilina-1/genética , Transdução de Sinais , Proteínas tau/genética
11.
Rev Esp Geriatr Gerontol ; 48(2): 79-88, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-23332579

RESUMO

Resveratrol is a natural polyphenol which can be found in many plants and fruits, such as peanuts, mulberries, blueberries and, above all, in grapes and red wine. Its synthesis is regulated by the presence of stressful factors, such as fungal contamination and ultra-violet radiation. In plants, it plays a role as a phytoalexin, showing a capacity to inhibit the development of certain infections. Plant extracts which contain resveratrol have been employed by traditional medicine for more than 2000 years. Resveratrol was first isolated, and its properties were initially studied with scientific methods, thirty years ago. Its in vitro properties have been extensively studied and demonstrated. It is worth highlighting its activity as an anti-cancer agent, platelet anti-aggregation agent, anti-inflammatory, antiallergenic, etc. The activity of its in vivo properties are not so clear. There are many studies that report benefits on the cardiovascular system, illnesses such as diabetes, and in longevity. However, other authors did not find any agreement between in vitro and in vivo studies. This discrepancy is due to the bioavailability of resveratrol. After an oral dose, it has been demonstrated that the absorption is very high, but the metabolic pathways leave just a little free resveratrol in blood, therefore the bioavailability in the target tissues is very low and the concentrations used in in vitro studies are not found in these tissues. Thus, resveratrol is a very active molecule for maintaining health, but due to the low bioavailability not all the in vitro effects can be translated to in vivo. This opens a new potential approach, seeking derivatives of resveratrol that can be measured in the desired tissues.


Assuntos
Estilbenos , Animais , Disponibilidade Biológica , Humanos , Resveratrol , Estilbenos/química , Estilbenos/metabolismo , Estilbenos/farmacocinética , Estilbenos/farmacologia
12.
Chronobiol Int ; 29(7): 822-34, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22823866

RESUMO

Alzheimer disease (AD) is a neurodegenerative disorder that primarily causes ß-amyloid accumulation in the brain, resulting in cognitive and behavioral deficits. AD patients, however, also suffer from severe circadian rhythm disruptions, and the underlying causes are still not fully known. Patients with AD show reduced systemic melatonin levels. This may contribute to their symptoms, since melatonin is an effective chronobiotic and antioxidant with neuroprotective properties. Here, the authors critically assessed the effects of long-term melatonin treatment on circadian system function, hippocampal oxidative stress, and spatial memory performance in the APPswe/PS1 double transgenic (Tg) mouse model of AD. To test if melatonin MT1/MT2 receptor activation, alone, was involved, the authors chronically treated some mice with the selective MT1/MT2 receptor agonist ramelteon. The results indicate that many of the circadian and behavioral parameters measured, including oxidative stress markers, were not significantly affected in these AD mice. During the day, though, Tg controls (Tg-CON) showed significantly higher mean activity and body temperature (BT) than wild-type (WT) mice. Overall, BT rhythm amplitude was significantly lower in Tg than in WT mice. Although melatonin treatment had no effect, ramelteon significantly reduced the amplitude of the BT rhythm in Tg mice. Towards the end of the experiment, Tg mice treated with ramelteon (Tg-RAM) showed significantly higher circadian rhythm fragmentation than Tg-CON and reduced circadian BT rhythm strength. The free-running period (τ) for the BT and locomotor activity (LA) rhythms of Tg-CON was <24 h. Whereas melatonin maintained τ at 24 h for BT and LA in both genotypes, ramelteon treatment had no effect. In the behavioral tests, the number of approaches and time spent exploring novel objects were significantly higher in Tg-CON than WT controls. Brain tissue analysis revealed significant reduction in hippocampal protein oxidation in Tg-MEL and Tg-RAM compared with Tg-CON animals. These results suggest that not all aspects of the circadian system are affected in the APPswe/PS1 mice. Therefore, care should be taken when extending the results obtained in Tg mice to develop new therapies in humans. This study also revealed the complexity in the therapeutic actions of melatonin and ramelteon in this mouse model of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Indenos/farmacologia , Melatonina/farmacologia , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Temperatura Corporal , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Melatonina/fisiologia , Memória/efeitos dos fármacos , Memória/fisiologia , Camundongos , Camundongos Transgênicos , Atividade Motora , Proteínas Mutantes/genética , Estresse Oxidativo , Presenilina-1/genética , Receptores de Melatonina/agonistas
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