CB - DFIS - Artigos publicados em periódicos

URI Permanente para esta coleçãohttps://repositorio.ufrn.br/handle/1/16

Navegar

Agora exibindo 1 - 20 de 39

Development of new techniques for behavioral evaluation In animals submitted to facial nerve damage
(Research Journal of Pharmaceutical, Biological and Chemical Sciences, 2019) Oliveira, Lucidio Clebeson de; Oliveira, Eligleidson José Vidal de; Lucena, Eudes Euler de Souza; Cavalcanti, José Rodolfo Lopes de Paiva; Fernandes, João Paulo Costa; Souza Júnior, José Edvan de; Cavalcante, Jeferson de Souza; Azevedo, Eduardo Pereira de; Rêgo, Amália Cinthia Meneses do; Araújo Filho, Irami; Castro, Aline Brito Ferreira de; Guzen, Fausto Pierdoná
Three new methods for evaluating facial nerve injury were developed: Spontaneous ocular opening, vibrissae reflex and resistance to upper eyelid lifting. Nerve crush injury was performed by pressing the mice’s facial nerve with forceps for 30 seconds. Scores were given based on the comparison between the behavioral assessment of the injured and non-injured sides. Facial nerve injury is currently evaluated by observing the movement of the mice’s vibrissae and the ocular closure. In this study, three additional tests are proposed. Therefore, a wider evaluation can be accomplished where all the aspects of the facial mimicry can be assessed. The use of the 3 new methods described in this study, in addition to the 2 methods currently used, allows a complete behavioral assessment of facial nerve lesions as several behavioral aspects related to these injuries can be evaluated
Combination sciatic nerve graft and fibroblastic growth factor 2 promotestissue regeneration for NF-200 and 5-HT in spinal cord injury
(Research Journal of Pharmaceutical, Biological and Chemical Sciences, 2018-07) Fernandes, Aline Samaya Santos; Castro, Aline Brito Ferreira de; Rêgo, Amália Cinthia Meneses do; Araújo Filho, Irami; Lucena, Eudes Euler de Souza; Cavalcanti, José Rodolfo Lopes de Paiva; Costa, Ianara Mendonça da; Cavalcante, Jeferson de Souza; Costa, Mirian Stela Maris de Oliveira; Guzen, Fausto Pierdoná
Traumatic injury to the spinal cord results in a rapid and significant loss of function. One barrier to successful regeneration in the adult CNS is the diminished axonal growth capacity after maturation. Therefore, strategies that seek to promote the restoration of function to the chronically injured spinal cord have high therapeutic value. Neurotrophic factors and peripheral nerves are known to be good substrates for bridging the lesions associatedwith CNS trauma. The role of fibroblast growth factor-2, when added to the sciatic nerve, was examined following spinal cord injury in a rat. We evaluated whether FGF-2 added to a sciatic nerve graft placed in a gap promoted nerve recovery following a complete transection of the spinal cord and if it could enhance neuronal plasticity. Rats underwent a transection at the thoracic level, which was repaired with saline or a fragment of the sciatic nerve. In another group, FGF-2 was added immediately after thelesion. The effects of FGF-2 and the fragment of the sciatic nerve graft on neuronal plasticity were investigated at the epicenterof the injury using NF-200 and 5-HT immunoreactivity after 8 weeks.A high number of NF-200 and 5-HT immunoreactive fibers were observed in the treated groups with sciatic nerve graft in the presence or absence of FGF-2 when compared to the saline group. However, a small number of NF-200(p=0.03)and 5-HT fibers were observed in the epicenter of the graft when FGF-2 was added,when compared to the group that received sciatic nerve graft. These results indicate that sciatic nerve grafting favors the growth of fibers in the traumatized spinal cord, an effect that is slightly influenced by the addition of FGF-2 to the NF-200 and 5-HT immunoreactive fibers
Expansion and phenotypic changes of mouse bone marrow mesenchymal cells cultured with FGF-2 and facial nerve-conditioned medium
(Sociedade Chilena de Anatomía, 2018-09) Lucena, Eudes Euler de Souza; Morais, Hécio Henrique Araújo de; Araújo, Dayane Pessoa de; Cavalcanti, José Rodolfo Lopes de Paiva; Azevedo, Eduardo Pereira de; Queiroz, Dinalva Brito de; Botelho, Marco Antônio; Rêgo, Amália Cinthia Meneses do; Araújo Filho, Irami; Barboza, Carlos Augusto Galvão; Nascimento Júnior, Expedito Silva do; Costa, Miriam Stela Maris de Oliveira; Cavalcante, Jeferson de Sousa; Guzen, Fausto Pierdoná
Mesenchymal cells (MCs) exhibit great regenerative potential due to their intrinsic properties and ability to restore tissue function, either directly through transdifferentiation or indirectly through paracrine effects. This study aimed to evaluate morphometric and phenotypic changes in MCs grown with facial nerve-conditioned medium in the presence or absence of fibroblast growth factor 2 (FGF-2). For quantitative phenotypic analysis, the expression of GFAP, OX-42, MAP-2, β-tubulin III, NeuN, and NF-200 was analyzed by immunocytochemistry. Cells cultured with facial nerve-conditioned medium in the presence of FGF-2 expressed GFAP, OX-42, MAP-2, β-tubulin III, NeuN, and NF-200. On average, the area and perimeter of GFAP-positive cells were higher in the group cultured with facial nerve-conditioned medium compared to the group cultured with conditioned medium and FGF-2 (p=0.0001). This study demonstrated the plasticity of MCs for neuronal and glial lineages and opens up new research perspectives in cell therapy and trans.differentiation
Astragaloside IV supplementation promotes a neuroprotective effect in experimental models of neurological disorders: a systematic review
(Bentham Science Publishers, 2019-06-19) Costa, Ianara M.; Lima, Francisca O. V.; Fernandes, Luciana C. B.; Norrara, Bianca; I. Neta, Francisca; Alves, Rodrigo D.; Cavalcanti, José R. L. P.; Lucena, Eudes Euler de Souza; Cavalcante, Jeferson de Souza; Rego, Amalia C. M.; Araújo Filho, Irami; Queiroz, Dinalva B.; Freire, Marco A. M.; Guzen, Fausto P.
Background: Neurological disorders constitute a growing worldwide concern due to the progressive aging of the population and the risky behavior they represent. Herbal medicines have scientific relevance in the treatment of these pathologies. One of these substances, Astragaloside IV (AS-IV), is the main active compound present in the root of Astragalus membranaceus (Fisch.) Bge, a Chinese medicinal herb with neuroprotective properties. Objective: In the present study we performed a systematic review that sought to comprehend the neuroprotective effect presented by AS-IV in experimental models of neurological disorders. Methods: This study is a systematic review, where an electronic search in United States National Library of Medicine (PubMed), Science Direct, Cochrane Library, Scientific Electronic Library Online (SciELO), Scopus, Web of Science, Medline via Proquest and Periodicos Capes databases covering the years between 2007 and 2017, using “Astragaloside IV” and “Neurodegenerative diseases”; “Astragaloside IV” and “ Neurological disorders” as reference terms was made. Results: A total of 16 articles were identified, in which the efficacy of AS-IV was described in experimental models of Parkinson’s disease, Alzheimer’s disease, cerebral ischemia and autoimmune encephalomyelitis, by improving motor deficits and/or neurochemical activity, especially antioxidant systems, reducing inflammation and oxidative stress. Conclusion: The findings of the present study indicate that the administration of AS-IV can improve behavioral and neurochemical deficits largely due to its antioxidant, antiapoptotic and antiinflammatory properties, emerging as an alternative therapeutic approach for the treatment of neurological disorders
Nuclear organization of the substantia nigra, ventral tegmental area and retrorubral field of the common marmoset (Callithrix jacchus): a cytoarchitectonic and TH-immunohistochemistry study
(Elsevier, 2016-11) Cavalcanti, José R. L. P.; Pontes, André L. B.; Fiuza, Felipe P.; Silva, Kayo D. A.; Guzen, Fausto P.; Lucena, Eudes Euler de Souza; Nascimento Júnior, Expedito Silva do; Cavalcante, Judney Cley; Costa, Miriam Stela Maris de Oliveira; Engelberth, Rovena Clara Galvao Januario; Cavalcante, Jeferson de Souza
It is widely known that the catecholamine group is formed by dopamine, noradrenaline and adrenaline. Its synthesis is regulated by the enzyme called tyrosine hydroxylase. 3-hydroxytyramine/dopamine (DA) is a precursor of noradrenaline and adrenaline synthesis and acts as a neurotransmitter in the central nervous system. The three main nuclei, being the retrorubral field (A8 group), the substantia nigra pars compacta (A9 group) and the ventral tegmental area (A10 group), are arranged in the die-mesencephalic portion and are involved in three complex circuitries – the mesostriatal, mesolimbic and mesocortical pathways. These pathways are involved in behavioral manifestations, motricity, learning, reward and also in pathological conditions such as Parkinson’s disease and schizophrenia. The aim of this study was to perform a morphological analysis of the A8, A9 and A10 groups in the common marmoset (Callithrix jacchus – a neotropical primate), whose morphological and functional characteristics support its suitability for use in biomedical research. Coronal sections of the marmoset brain were submitted to Nissl staining and TH-immunohistochemistry. The morphology of the neurons made it possible to subdivide the A10 group into seven distinct regions: interfascicular nucleus, raphe rostral linear nucleus and raphe caudal linear nucleus in the middle line; paranigral and parainterfascicular nucleus in the middle zone; the rostral portion of the ventral tegmental area nucleus and parabrachial pigmented nucleus located in the dorsolateral portion of the mesencephalic tegmentum. The A9 group was divided into four regions: substantia nigra compacta dorsal and ventral tiers; substantia nigra compacta lateral and medial clusters. No subdivisions were made for the A8 group. These results reveal that A8, A9 and A10 are phylogenetically stable across species. As such, further studies concerning such divisions are necessary in order to evaluate the occurrence of subdivisions that express DA in other primate species, with the aim of characterizing its functional relevance
Effect of FGF-2 and sciatic nerve grafting on ChAT expression in dorsal root ganglia neurons of spinal cord transected rats
(Elsevier, 2016-03) Guzen, Fausto Pierdoná; Araújo, Dayane Pessoa de; Lucena, Eudes Euler de Souza; Morais, Hécio Henrique Araújo de; Cavalcanti, José Rodolfo Lopes de Paiva; Nascimento Junior, Expedito Silva do; Costa, Miriam Stela Maris de Oliveira; Cavalcante, Jeferson de Souza
Neurotrophic factors and peripheral nerves are known to be good substrates for bridging CNS trauma. The involvement of fibroblast growth factor-2 (FGF-2) activation in the dorsal root ganglion (DRG) was examined following spinal cord injury in the rat. We evaluated whether FGF-2 increases the ability of a sciatic nerve graft to enhance neuronal plasticity, in a gap promoted by complete transection of the spinal cord. The rats were subjected to a 4 mm-long gap at low thoracic level and were repaired with saline (Saline or control group, n = 10), or fragment of the sciatic nerve (Nerve group, n = 10), or fragment of the sciatic nerve to which FGF-2 (Nerve + FGF-2 group, n = 10) had been added immediately after lesion. The effects of the FGF-2 and fragment of the sciatic nerve grafts on neuronal plasticity were investigated using choline acetyl transferase (ChAT)-immunoreactivity of neurons in the dorsal root ganglion after 8 weeks. Preservation of the area and diameter of neuronal cell bodies in dorsal root ganglion (DRG) was seen in animals treated with the sciatic nerve, an effect enhanced by the addition of FGF-2. Thus, the addition of exogenous FGF-2 to a sciatic nerve fragment grafted in a gap of the rat spinal cord submitted to complete transection was able to improve neuroprotection in the DRG. The results emphasized that the manipulation of the microenvironment in the wound might amplify the regenerative capacity of peripheral neurons
Evidence for age-related changes in the circadian activity rhythm of the diurnal primate Callithrix jacchus: a case report
(Taylor and Francis, 2016-01-29) Gonçalves, Fabiana Barbosa; Borges, Galileu R.; Gonçalves, Bruno S. B.; Cavalcante, Jeferson de Souza; Menezes, Alexandre A. L.; Azevedo, Carolina Virginia Macedo de
Many cross-sectional studies have shown that circadian rhythms change with age, but such age-related modifications are gradual and may be insufficiently described by cross- sectional studies. In the present case study, circadian activity rhythm (CAR) was evaluated longitudinally, in both LD (12:12) and LL conditions, on two occasions in a single male marmoset: when “adult” (3 y.o.) and when “old” (9 y.o.). When adult, the CAR synchronized with positive phase angles for the onset and offset of activity. In LL, the rhythm free-ran with τ < 24 h. When old, the animal showed a significant phase delay of its activity rhythm with respect to the LD cycle (t-test, p<0.01) and a reduction on total daily activity (t-test, p<0.01), with signs of lesser stability, greater fragmentation and some loss of photic synchronization. In LL, the period free-ran with τ > 24 h. We conclude that aging attenuates photic synchronization and the expression of a circadian activity rhythm in LL in the marmoset. Further studies with a larger number of individuals are needed to confirm these findings
Aging-related changes on social synchronization of circadian activity rhythm in a diurnal primate (Callithrix jacchus)
(Taylor and Francis, 2020-06-23) Gonçalves, Fabiana Barbosa; Gonçalves, Bruno S. B.; Cavalcante, Jeferson de Souza; Azevedo, Carolina Virginia Macedo de
The input of environmental time cues and expression of circadian activity rhythms may change with aging. Among nonphotic zeitgebers, social cues from conspecific vocalizations may contribute to the stability and survival of individuals of social species, such as nonhuman primates. We evaluated aging- related changes on social synchronization of the circadian activity rhythm (CAR) in a social diurnal primate, the common marmoset. The activity of 18 male marmosets was recorded by actiwatches in two conditions. (1) Experimental – 4 young adult (5 ± 2 yrs of age) and 4 older (10 ± 2 yrs of age) animals maintained under LD 12/12 h and LL in a room with full insulation for light but only partial insulation for sound from vocalizations of conspecifics maintained outdoors in the colony; and (2) Control – 10 young adult animals maintained outdoors in the colony (5 animals as a control per age group). In LL, the CAR of young adults showed more stable synchronization with controls. Among the aged marmosets, two free-ran with τ > 24 h, whereas the other two showed relative coordination during the first 30 days in LL, but free-ran thereafter. These differences were reflected in the “social” phase angles (ψon and ψoff) between rhythms of experimental and control animal groups. Moreover, the activity patterns of aged animals showed lower social synchrony with controls compared to young adults, with the time lags of the time series between each experimental group and control group being negative in aged and positive in young adult animals (t-test, p < 0.05). The index of stability of the CAR showed no differences according to age, while the intradaily variability of the CAR was higher in the aged animals during LD-resynchronization, who took additional days to resynchronize. Thus, the social modulation on CAR may vary with age in marmosets. In the aged group, there was a lower effect of social synchronization, which may be associated with aging-related changes in the synchro- nization and generation of the CAR as well as in system outputs
Optimizing the detection of nonstationary signals by using recurrence analysis
(American Institute of Physics, 2018-08-24) Prado, Thiago de Lima; Lima, Gustavo Zampier dos Santos; Lobão-Soares, Bruno; Nascimento, George Carlos do; Corso, Gilberto; Araújo, John Fontenele; Kurths, Jürgen; Lopes, Sérgio Roberto
Recurrence analysis and its quantifiers are strongly dependent on the evaluation of the vicinity threshold parameter, i.e., the threshold to regard two points close enough in phase space to be considered as just one. We develop a new way to optimize the evaluation of the vicinity threshold in order to assure a higher level of sensitivity to recurrence quantifiers to allow the detection of even small changes in the dynamics. It is used to promote recurrence analysis as a tool to detect nonstationary behavior of time signals or space profiles. We show that the ability to detect small changes provides information about the present status of the physical process responsible to generate the signal and offers mechanisms to predict future states. Here, a higher sensitive recurrence analysis is proposed as a precursor, a tool to predict near future states of a particular system, based on just (experimentally) obtained signals of some available variables of the system. Comparisons with traditional methods of recurrence analysis show that the optimization method developed here is more sensitive to small variations occurring in a signal. The method is applied to numerically generated time series as well as experimental data from physiology
Hippocampal and cortical communication around micro-arousals in slow-wave sleep
(Nature Publishing Group, 2019-04-10) Lima, Gustavo Zampier dos Santos; Lobão-Soares, Bruno; Corso, Gilberto; Belchior, Hindiael Aeraf; Lopes, Sergio Roberto Lopes; Prado, Thiago de Lima; Nascimento, George Carlos do; Araújo, John Fontenele; Ivanov, Plamen Ch.
Sleep plays a crucial role in the regulation of body homeostasis and rhythmicity in mammals. Recently, a specific component of the sleep structure has been proposed as part of its homeostatic mechanism, named micro-arousal. Here, we studied the unique progression of the dynamic behavior of cortical and hippocampal local field potentials (LFPs) during slow-wave sleep-related to motor-bursts (micro-arousals) in mice. Our main results comprised: (i) an abrupt drop in hippocampal LFP amplitude preceding micro-arousals which persisted until the end of motor-bursts (we defined as t interval, around 4s) and a similar, but delayed amplitude reduction in cortical (S1/M1) LFP activity occurring at micro-arousal onset; (ii) two abrupt frequency jumps in hippocampal LFP activity: from Theta (6–12 Hz) to Delta (2–4 Hz), also t seconds before the micro-arousal onset, and followed by another frequency jump from Delta to Theta range (5–7 Hz), now occurring at micro-arousal onset; (iii) a pattern of cortico-hippocampal frequency communication precedes micro-arousals: the analysis between hippocampal and cortical LFP fluctuations reveal high coherence during τ interval in a broader frequency band (2–12 Hz), while at a lower frequency band (0.5–2 Hz) the coherence reaches its maximum after the onset of micro-arousals. In conclusion, these novel findings indicate that oscillatory dynamics pattern of cortical and hippocampal LFPs preceding micro-arousals could be part of the regulatory processes in sleep architecture
Disruption of neocortical synchronisation during slow-wave sleep in the rotenone model of Parkinson’s disease
(Wiley, 2020-07-28) Lima, Gustavo Zampier dos Santos; Targa, Adriano D. S.; Cavalcante, Samantha de Freitas; Rodrigues, Lais S.; Araújo, John Fontenele; Torterolo, Pablo; Andersen, Monica L.; Lima, Marcelo M. S.
Parkinson’s disease motor dysfunctions are associated with improperly organised neural oscillatory activity. The presence of such disruption at the early stages of the disease in which altered sleep is one of the main features could be a relevant predictive feature. Based on this, we aimed to investigate the neocortical synchronisation dynamics during slow-wave sleep (SWS) in the rotenone model of Parkinson’s disease. After rotenone administration within the substantia nigra pars compacta, one group of male Wistar rats underwent sleep–wake recording. Considering the association between SWS oscillatory activity and memory consolidation, another group of rats underwent a memory test. The fine temporal structure of synchronisation dynamics was evaluated by a recently developed technique called first return map. We observed that rotenone administration decreased the time spent in SWS and altered the power spectrum within different frequency bands, whilst it increased the transition rate from a synchronised to desynchronised state. This neurotoxin also increased the probability of longer and decreased the probability of shorter desynchronisation events. At the same time, we observed impairment in object recognition memory. These findings depict an electrophysiological fingerprint represented by a disruption in the typical oscillatory activity within the neocortex at the early stages of Parkinson’s disease, concomitant with a decrease in the time spent in SWS and impairment in recognition memory
Daily anticipatory rhythms of behavior and body temperature in response to glucose availability in rats
(2012) Carneiro, Breno T. S.; Fernandes, Diego A. C.; Medeiros, Caio F. P.; Diniz, Nathália L.; Araujo, John Fontenele
When food is available recurrently at a particular time of day, several species increase their locomotion in the hours that precede food delivery, a phenomenon called food anticipatory activity (FAA). In mammals, many studies have shown that FAA is driven by a food-entrained circadian oscillator (FEO) that is distinct from the light-entrained pacemaker in the suprachiasmatic nucleus of the hypothalamus. Few studies have investigated the effect of sugar ingestion on food anticipatory rhythms and the FEO. We aimed to extend the understanding of the role of glucose on the emergence of food anticipatory rhythms by investigating whether glucose ingestion is sufficient to produce daily food anticipation, reflected by motor activity and core body temperature rhythms. Under a 12 h/12 h light/dark cycle, chow-deprived rats had glucose solution available between Zeitgeber Time (ZT) 6 and ZT 9 for 10 days (glucose restriction group), whereas control animals had chow available within the same time window (chow restriction group). Animals in both groups exhibited anticipatory motor activity and body temperature around the fourth day of the scheduled food restriction. Glucose-fed rats ingested ~15 kcal on the days immediately before FAA emergence and reached an intake of ~20 kcal/day, whereas chow-fed rats ingested ~40 kcal/day. The glucose restriction group exhibited a pattern of food anticipation (activity and temperature) that was extremely similar to that observed in the chow restriction group. We conclude that glucose ingestion is a sufficient temporal cue to produce recurrent food anticipation, reflected by activity and temperature rhythms, in rats.
Latitudinal cline of chronotype
(2017-07-14) Miguel, Mario André Leocadio; Louzada, Fernando Mazzili; Duarte, Leandro Lourenção; Areas, Roberta Peixoto; Alam, Marilene; Freire, Marcelo Ventura; Araujo, John Fontenele; Barreto, Luiz Menna; Pedrazzoli, Mario
The rotation of the Earth around its own axis and around the sun determines the characteristics of the light/dark cycle, the most stable and ancient 24 h temporal cue for all organisms. Due to the tilt in the earth’s axis in relation to the plane of the earth’s orbit around the sun, sunlight reaches the Earth differentially depending on the latitude. The timing of circadian rhythms varies among individuals of a given population and biological and environmental factors underlie this variability. In the present study, we tested the hypothesis that latitude is associated to the regulation of circadian rhythm in humans. We have studied chronotype profiles across latitudinal cline from around 0° to 32° South in Brazil in a sample of 12,884 volunteers living in the same time zone. The analysis of the results revealed that humans are sensitive to the different sunlight signals tied to differences in latitude, resulting in a morning to evening latitudinal cline of chronotypes towards higher latitudes
Nonparametric methods in actigraphy: An update
(2014-09-03) Gonçalves, Bruno S.B.; Cavalcanti, Paula R.A.; Tavares, Gracilene R.; Campos, Tania F.; Araujo, John F.
Circadian rhythmicity in humans has been well studied using actigraphy, a method of measuring gross motor movement. As actigraphic technology continues to evolve, it is important for data analysis to keep pace with new variables and features. Our objective is to study the behavior of two variables, interdaily stability and intradaily variability, to describe rest activity rhythm. Simulated data and actigraphy data of humans, rats, and marmosets were used in this study. We modified the method of calculation for IV and IS by modifying the time intervals of analysis. For each variable, we calculated the average value (IVm and ISm) results for each time interval. Simulated data showed that (1) synchronization analysis depends on sample size, and (2) fragmentation is independent of the amplitude of the generated noise. We were able to obtain a significant difference in the fragmentation patterns of stroke patients using an IVm variable, while the variable IV60 was not identified. Rhythmic synchronization of activity and rest was significantly higher in young than adults with Parkinson׳s when using the ISM variable; however, this difference was not seen using IS60. We propose an updated format to calculate rhythmic fragmentation, including two additional optional variables. These alternative methods of nonparametric analysis aim to more precisely detect sleep–wake cycle fragmentation and synchronization.
Efeitos agudos do exercício físico no tratamento da dependência química
(2017-04) Ferreira, Sionaldo Eduardo; Santos, Anny Kalinne de Melo dos; Okano, Alexandre Hideki; Gonçalves, Bruno da Silva Brandão; Araújo, John Fontenele
Foram avaliados os efeitos do exercício físico na capacidade de atenção, na memória, no desejo de usar drogas, na percepção de esforço e prazer e no estado de humor de 16 indivíduos em tratamento para dependência de drogas. Foram usados a escala de Brunel, o teste de cancelamento de números, o teste dos blocos de Corsi, a escala de Borg e escala de valência afetiva ao esforço físico nas situações controle, pré e pós‐realização de uma sessão de exercícios físicos (60 min). Foi observada redução no desejo de usar drogas e no tempo de execução do teste de cancelamento de números, e aumento no número de blocos recordados. Os resultados apontam a importância do profissional da educação física nas equipes para tratamento da dependência química.
Caminos de la neurociencia en América Latina
(2013-01) Cardenas, Fernando P.; Araujo, John Fontenele; León, Laura Andrea
Não possui resumo.
Dream characteristics in a Brazilian sample: an online survey focusing on lucid dreaming
(2013-12) Rolim, Sérgio A. Mota; Targino, Zé H.; Souza, Bryan C.; Blanco, Wilfredo; Araujo, John F.; Ribeiro, Sidarta
During sleep, humans experience the offline images and sensations that we call dreams, which are typically emotional and lacking in rational judgment of their bizarreness. However, during lucid dreaming (LD), subjects know that they are dreaming, and may control oneiric content. Dreaming and LD features have been studied in North Americans, Europeans and Asians, but not among Brazilians, the largest population in Latin America. Here we investigated dreams and LD characteristics in a Brazilian sample (n = 3,427; median age = 25 years) through an online survey. The subjects reported recalling dreams at least once a week (76%), and that dreams typically depicted actions (93%), known people (92%), sounds/voices (78%), and colored images (76%). The oneiric content was associated with plans for the upcoming days (37%), memories of the previous day (13%), or unrelated to the dreamer (30%). Nightmares usually depicted anxiety/fear (65%), being stalked (48%), or other unpleasant sensations (47%). These data corroborate Freudian notion of day residue in dreams, and suggest that dreams and nightmares are simulations of life situations that are related to our psychobiological integrity. Regarding LD, we observed that 77% of the subjects experienced LD at least once in life (44% up to 10 episodes ever), and for 48% LD subjectively lasted less than 1 min. LD frequency correlated weakly with dream recall frequency (r = 0.20, p < 0.01), and LD control was rare (29%). LD occurrence was facilitated when subjects did not need to wake up early (38%), a situation that increases rapid eye movement sleep (REMS) duration, or when subjects were under stress (30%), which increases REMS transitions into waking. These results indicate that LD is relatively ubiquitous but rare, unstable, difficult to control, and facilitated by increases in REMS duration and transitions to wake state. Together with LD incidence in USA, Europe and Asia, our data from Latin America strengthen the notion that LD is a general phenomenon of the human species.
Food entrainment: major and recent findings
(2012-11) Carneiro, Breno T. S.; Araujo, John F.
Mammals exhibit daily anticipatory activity to cycles of food availability. Studies on such food anticipatory activity (FAA) have been conducted mainly in nocturnal rodents. They have identified FAA as the behavioral output of a food entrained oscillator (FEO), separate of the known light entrained oscillator (LEO) located in the suprachiasmatic nucleus (SCN) of hypothalamus. Here we briefly review the main characteristics of FAA. Also, we present results on four topics of food anticipation: (1) possible input signals to FEO, (2) FEO substrate, (3) the importance of canonical clock genes for FAA, and (4) potential practical applications of scheduled feeding. This mini review is intended to introduce the subject of food entrainment to those unfamiliar with it but also present them with relevant new findings on the issue.
Chronotype ontogeny related to gender
(2014) Duarte, L.L; Menna-Barreto, L.; Miguel, M.A.L; Louzada, F.; Araújo, John Fontenele; Alam, M.; Areas, R.; Pedrazzoli, M.
Chronotype is an established concept designed to identify distinct phase relationships between the expression of circadian rhythms and external synchronizers in humans. Although it has been widely accepted that chronotype is subjected to ontogenetic modulation, there is no consensus on the interaction between age and gender. This study aimed to determine the relationship between age- and gender-related changes in the morningness-eveningness character in a large sample of people. A total of 14,650 volunteers were asked to complete the Brazilian version of the Horne and Östberg chronotype questionnaire. The data demonstrated that, on average, women were more morning-oriented than men until the age of 30 and there were no significant differences between men and women from 30 to 45 years of age. In contrast to the situation observed until the age of 30, women older than 45 years were more evening-oriented than men. These results suggest that the ontogenetic development of the circadian timekeeping system is more plastic in men, as represented by the larger amplitude of chronotype changes throughout their aging process. The phase delay of adolescence and phase advance of the elderly seem to be phenomena that are more markedly present in men than in women. Thus, our data, for the first time, provide support that sharply opposes the view that there is a single path toward morningness as a function of age, regardless of gender.
A fresh look at the use of nonparametric analysis in actimetry
(2015-04) Gonçalves, B.S.B.; Adamowicz, Taísa; Louzada, Fernando Mazzilli; Moreno, Claudia Roberta; Araujo, John Fontenele
Actimetry has been used to estimate the sleep–wake cycle instead of the rest-activity rhythm. Although algorithms for assessing sleep from actimetry data exist, it is useful to analyze the rest-activity rhythm using nonparametric methods. This would then allow rest-activity rhythm stability, fragmentation and amplitude to be quantified. In addition, sleep and wakefulness efficiency can be quantified separately. These variables have been used in studies analyzing the effect of age, diseases and their respective treatments on human circadian rhythmicity. In this study, we carried out a comprehensive analysis of the main results from published articles and devised a functional model of interaction among the several components involved in generating the sleep–wake cycle. The nonparametric variables render it possible to infer the main characteristics of circadian rhythms, such as synchronization with a zeitgeber, and its amplitude and robustness

SIGAA

Navegar

Submissões Recentes