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Melatonin is vital in human circadian rhythm and infant development. This scoping review summarized the current knowledge about melatonin's presence and effects in human milk to promote better understanding of its secretion pattern and clinical advancement of maternal-infant health. The review followed the Joanna Briggs Institute guideline and answered the question: What is the current knowledge about melatonin hormone in human milk? The databases searched were PubMed, CINAHL, SCOPUS, Web of Science, LILACS, Scielo, EMBASE, Science Direct, Eric, Cochrane, in addition to grey literature and reference lists of included sources. Research papers included English, Spanish, or Portuguese languages, regardless of study type or publication date. The study selection and data extraction involved two independent reviewers. Twenty-nine studies met inclusion criteria. The studies, conducted between 1993 and 2023, employed diverse designs, with cross-sectional studies being the most prevalent. Melatonin concentration exhibited a consistent pattern, being higher at night, and elevated in colostrum. The analysis methods for melatonin concentration evolved, with recent advancements contributing to more accurate measurements. Factors influencing melatonin levels, such as delivery type, maternal age, and health conditions, demonstrated a complex relationship, potentially impacting the health and development of infants. The dynamic nature of melatonin in human milk calls for continued interdisciplinary research, bridging gaps between clinical, biochemical, and epidemiological perspectives. Standardizing melatonin analysis methods are needed. Nurses should assess factors influencing melatonin levels in milk to promote interventions and guidance aimed at enhancing the regulation of the circadian cycle during the perinatal period and its benefits.
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Melatonina , Leite Humano , Humanos , Leite Humano/química , Feminino , Ritmo Circadiano/fisiologia , Recém-Nascido , Lactente , Aleitamento MaternoRESUMO
Early exposure to stressors affects how the organism reacts to stimuli, its emotional state throughout life, and how it deals with emotional memories. Consequently, it may affect susceptibility to psychopathology later in life. We used an animal model of early stress by maternal separation to study its potential impact on the extinction of aversive memories and anxiety-like behavior in adulthood, as well as its effects on mitochondrial functionality, inflammatory and astrocytic markers in the amygdala. We also assessed whether a diet enriched with linseed oil, known for its high content in omega-3 fats, could be used to attenuate the behavioral and neurochemical effects of early stress. Litters of Wistar rats were divided into controls (intact) or subjected to maternal separation (MS). They were subdivided into two groups receiving isocaloric diets enriched in soy or linseed oils at weaning. In adulthood, the animals were exposed to the open field and the elevated plus maze, to evaluate exploratory activity and anxiety-like behavior. They were also trained in a context of fear conditioning, and afterward subjected to an extinction session, followed by a test session to evaluate the extinction memory. Amygdalae were evaluated for inflammatory cytokines (interleukin (IL)-1beta, IL-6, and tumor-necrose factor (TNF)-alpha), mitochondrial functionality, and astrocyte markers (glial fibrillary acidic protein - GFAP, S100B, and glutamine synthetase activity). MS induced anxiety-like behavior in the elevated plus-maze, which was reversed by a diet enriched in linseed oil offered from weaning. When testing the memory of an extinction session of fear conditioning, MS animals showed more freezing behavior. MS males receiving a linseed oil-enriched diet had lower functional mitochondria in the amygdala. In addition, MS led to increased inflammatory cytokines, particularly IL-1beta, and the diet enriched in linseed oil further increased these levels in MS animals. MS also increased S100B levels. These results point to a higher emotionality presented by MS animals, with higher levels of inflammatory cytokines and S100B. While a diet enriched in linseed oil attenuated anxiety-like behavior, it further altered amygdala IL-1beta and reduced mitochondria functionality, particularly in males. MS also increased glutamine synthetase activity in the amygdala, and this effect was higher when the animals received a diet enriched in linseed oil, particularly in females. In conclusion, these results point to MS effects on emotional behavior, and neurochemical alterations in the amygdala, with sex-specific effects. Although a diet enriched in linseed oil appears to be able to reverse some of MS behavioral effects, these results must be considered with caution, since biochemical parameters could be worsened in MS animals receiving a linseed oil-enriched diet. This knowledge is important for the understanding of mechanisms of action of strategies aiming to reverse early stress effects, and future studies are warranted to determine possible interventions to promote resilience.
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Tonsila do Cerebelo , Ansiedade , Astrócitos , Óleo de Semente do Linho , Mitocôndrias , Ratos Wistar , Estresse Psicológico , Animais , Óleo de Semente do Linho/farmacologia , Óleo de Semente do Linho/administração & dosagem , Ansiedade/metabolismo , Tonsila do Cerebelo/metabolismo , Masculino , Feminino , Mitocôndrias/metabolismo , Estresse Psicológico/metabolismo , Ratos , Astrócitos/metabolismo , Inflamação/metabolismo , Memória/fisiologia , Memória/efeitos dos fármacos , Extinção Psicológica/fisiologia , Extinção Psicológica/efeitos dos fármacos , Privação MaternaRESUMO
Excess exercise ventilation (high ventilation (VÌE)/carbon dioxide output (VÌCO2)) contributes significantly to dyspnea and exercise intolerance since the earlier stages of chronic obstructive pulmonary disease (COPD). A selective pulmonary vasodilator (inhaled nitric oxide) has shown to increase exercise tolerance secondary to lower VÌE/VÌCO2 and dyspnea in this patient population. We aimed to assess whether a clinically more practical option - oral sildenafil - would be associated with similar beneficial effects. In a randomized, placebo-controlled study, twenty-four patients with mild-to-moderate COPD completed, on different days, two incremental cardiopulmonary exercise tests (CPET) one hour after sildenafil or placebo. Eleven healthy participants performed a CPET in a non-interventional visit for comparative purposes with patients when receiving placebo. Patients (FEV1= 69.4 ± 13.5â¯% predicted) showed higher ventilatory demands (VÌE/VÌCO2), worse pulmonary gas exchange, and higher dyspnea during exercise compared to controls (FEV1= 98.3 ±11.6â¯% predicted). Contrary to our expectations, however, sildenafil (50â¯mg; N= 15) did not change exertional VÌE/VÌCO2, dead space/tidal volume ratio, operating lung volumes, dyspnea, or exercise tolerance compared to placebo (P>0.05). Due to the lack of significant beneficial effects, nine additional patients were trialed with a higher dose (100â¯mg). Similarly, active intervention was not associated with positive physiological or sensory effects. In conclusion, acute oral sildenafil (50 or 100â¯mg) failed to improve gas exchange efficiency or excess exercise ventilation in patients with predominantly moderate COPD. The current study does not endorse a therapeutic role for sildenafil to mitigate exertional dyspnea in this specific patient subpopulation. Clinical trial registry: https://ensaiosclinicos.gov.br/rg/RBR-4qhkf4 Web of Science Researcher ID: O-7665-2019.
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Estudos Cross-Over , Doença Pulmonar Obstrutiva Crônica , Troca Gasosa Pulmonar , Citrato de Sildenafila , Humanos , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/terapia , Masculino , Pessoa de Meia-Idade , Feminino , Troca Gasosa Pulmonar/efeitos dos fármacos , Troca Gasosa Pulmonar/fisiologia , Idoso , Teste de Esforço , Tolerância ao Exercício/efeitos dos fármacos , Tolerância ao Exercício/fisiologia , Exercício Físico/fisiologia , Vasodilatadores/administração & dosagem , Vasodilatadores/farmacologia , Dispneia/tratamento farmacológico , Dispneia/fisiopatologia , Ventilação Pulmonar/efeitos dos fármacos , Ventilação Pulmonar/fisiologiaRESUMO
To identify daily changes in the digestive physiology of Totoaba macdonaldi, the feed intake, activity (pepsin, trypsin, chymotrypsin, lipase, amylase, and L-aminopeptidase), and gene expression (aminopeptidase and maltase-glucoamylase) of key digestive enzymes were measured in the intestine and the pyloric caeca. Fish were fed for three weeks every four hours during the light period to apparent satiation, and samples were taken every four hours throughout a 24-h cycle under a 12:12 L:D photoperiod. The feed consumption steadily increased until the third feeding (16:00 h, ZT-8) and decreased significantly towards the end of the day. The activity of pepsin and alkaline enzymes (trypsin, chymotrypsin, lipase, amylase, and L-aminopeptidase) exhibited a pattern dependent on the presence of feed, showing a significant reduction during the hours of darkness (ZT-12 to ZT-24). Expression of the intestinal brush border enzyme (L-aminopeptidase) increased during the darkness period in anticipation of the feed ingestion associated with the subsequent light period. The cosinor analysis used to estimate the feed rhythms for all tested enzymes showed that activity in the intestine and pyloric caeca exhibited significant rhythmicity (p < 0.05). However, no rhythmicity was observed in the intestinal expression of maltase-glucoamylase. Our results demonstrate that some of the behavioral and digestive physiology features of totoaba directly respond to rhythmicity in feeding, a finding that should be considered when establishing optimized feeding protocols.
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Comportamento Alimentar , Animais , Comportamento Alimentar/fisiologia , Ritmo Circadiano/fisiologia , Digestão/fisiologia , FotoperíodoRESUMO
The hake fishery plays a crucial role due to its significant economic impact. The genus Merluccius includes 12 extant species found along the coasts of the Americas, Europe, and Africa. However, research on their digestive physiology and the enzymes involved in digestion, including proteases, remains limited. Proteases play a key role in protein digestion, a vital process for all living organisms. This study focused on screening the genomes of eight Merluccius spp. for eight specific proteases previously identified in Merluccius polli. Additionally, the study conducted biochemical analyses of proteases found in the stomach and intestine of Pacific whiting fish (Merluccius productus), comparing the results with the genomic findings. The analysis revealed that proteases across Merluccius spp. are conserved, although with slight variations, particularly in chymotrypsin and aspartic proteases. Biochemical characterization of M. productus identified at least three main proteases in the stomach, active at acidic pH, and at least seven proteases in the intestine, active at alkaline pH, as determined by electrophoresis. Further investigation, including specific inhibition studies, determination of molecular mass, and assessment of pH and temperature preferences for catalysis, revealed that one of the stomach proteases functioning at acidic pH likely belongs to the acid peptidase class, likely pepsin. Similarly, analysis of proteases active at alkaline pH indicated the presence of a chymotrypsin and a trypsin, consistent with genomic findings in M. productus. These results are important as they provide insights into the digestive physiology of Merluccius spp., contributing to a better understanding of their nutritional needs.
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Biologia Computacional , Gadiformes , Peptídeo Hidrolases , Animais , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/química , Proteínas de Peixes/metabolismo , Proteínas de Peixes/genética , Concentração de Íons de Hidrogênio , Digestão/fisiologia , FilogeniaRESUMO
Plants regulate gas exchange with the environment and modulate transpirational water flow through guard cells, which set the aperture of the stomatal pores. External and internal stimuli are detected by guard cells and integrated into a signalling network that modulate turgor pressure and, hence, pore size. Pathogen-associated molecular patterns are among the stimuli that induce stomatal closure, to prevent pathogen entry through the pores, and this response, also referred to as stomatal immunity, is one of the hallmarks of PAMP-triggered immunity. While reactive oxygen species (ROS)-mediated signalling plays a key role in stomatal immunity, also the gasotransmitter hydrogen sulphide (H2S) interacts with key components of the guard cell signalling network to induce stomatal closure. While the role of H2S, produced by the main cytosolic source L-cysteine desulfhydrase 1, has been already investigated, there are additional enzymatic sources that synthesize H2S in different subcellular compartments. Their function has remained enigmatic, however. In this work, we elucidate the involvement of the mitochondrial H2S source, ß-cyanoalanine synthase CAS-C1, on stomatal immunity induced by the bacterial PAMP flagellin (flg22). We show that cas-c1 plants are impaired to induce flg22-triggered stomatal closure and apoplastic ROS production, while they are more susceptible to bacterial surface inoculation. Moreover, mitochondrial H2S donor AP39 induced stomatal closure in an RBOHD-dependent manner, while depletion of endogenous H2S, impaired RBOHD-mediated apoplastic ROS production. In addition, pharmacological disruption of mitochondrial electron transport chain activity, affected stomatal closure produced by flg22, indicating its participation in the stomatal immunity response. Our findings add evidence to the emerging realization that intracellular organelles play a decisive role in orchestrating stomatal signalling and immune responses and suggest that mitochondrial-derived H2S is an important player of the stomatal immunity signalling network.
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Arabidopsis , Flagelina , Imunidade Vegetal , Estômatos de Plantas , Estômatos de Plantas/fisiologia , Arabidopsis/imunologia , Arabidopsis/genética , Arabidopsis/fisiologia , Flagelina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Liases/metabolismo , Liases/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Mitocôndrias/metabolismo , Sulfeto de Hidrogênio/metabolismo , Transdução de SinaisRESUMO
Emerging theories emphasize the crucial role of allostasis (anticipatory and adaptive regulation of the body's biological processes) and interoception (integration, anticipation, and regulation of internal bodily states) in adjusting physiological responses to environmental and bodily demands. In this review, we explore the disruptions in integrated allostatic interoceptive mechanisms in psychiatric and neurological disorders, including anxiety, depression, Alzheimer's disease, and frontotemporal dementia. We assess the biological mechanisms associated with allostatic interoception, including whole-body cascades, brain structure and function of the allostatic interoceptive network, heart-brain interactions, respiratory-brain interactions, the gut-brain-microbiota axis, peripheral biological processes (inflammatory, immune), and epigenetic pathways. These processes span psychiatric and neurological conditions and call for developing dimensional and transnosological frameworks. We synthesize new pathways to understand how allostatic interoceptive processes modulate interactions between environmental demands and biological functions in brain disorders. We discuss current limitations of the framework and future transdisciplinary developments. This review opens a new research agenda for understanding how allostatic interoception involves brain predictive coding in psychiatry and neurology, allowing for better clinical application and the development of new therapeutic interventions.
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Alostase , Interocepção , Transtornos Mentais , Humanos , Alostase/fisiologia , Interocepção/fisiologia , Transtornos Mentais/fisiopatologia , Encéfalo/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Eixo Encéfalo-Intestino/fisiologiaRESUMO
Polyploid varieties have been suggested as an alternative approach to promote drought tolerance in citrus crops. In this study, we compared the responses of diploid and tetraploid Sunki 'Tropical' rootstocks to water deficit when grafted onto 'Valencia' sweet orange trees and subjected to water withholding in isolation or competition experiments under potted conditions. Our results revealed that, when grown in isolation, tetraploid rootstocks took longer to show drought symptoms, but this advantage disappeared when grown in competition under the same soil moisture conditions. The differences in drought responses were mainly associated with variations in endogenous leaf levels of abscisic acid (ABA), hydrogen peroxide (H2O2) and carbohydrates among treatments. Overall, tetraploids were more affected by drought in individual experiments, showing higher H2O2 production, and in competition experiments, rapidly increasing ABA production to regulate stomatal closure and reduce water loss through transpiration. Therefore, our results highlight the crucial importance of evaluating diploid and tetraploid rootstocks under the same soil moisture conditions to better simulate field conditions, providing important insights to improve selection strategies for more resilient citrus rootstocks.
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Ácido Abscísico , Citrus , Secas , Peróxido de Hidrogênio , Folhas de Planta , Raízes de Plantas , Poliploidia , Água , Ácido Abscísico/metabolismo , Citrus/fisiologia , Citrus/genética , Raízes de Plantas/fisiologia , Folhas de Planta/fisiologia , Peróxido de Hidrogênio/metabolismo , Tetraploidia , Transpiração Vegetal/fisiologia , Solo/química , Diploide , Estresse Fisiológico , Estômatos de Plantas/fisiologiaRESUMO
The thalamic reticular nucleus controls information processing in thalamocortical neurons. GABAergic neurons present in this nucleus express the α3 subunit of postsynaptic GABAA receptors, which bind GABA from globus pallidus neurons. Pallidal neurons, in turn, have dopaminergic D4 receptors in their axon terminals. The thalamic reticular nucleus connects reciprocally with the thalamus, and it receives afferents from the brain cortex, as well as from other brain structures that have an important role in the modulation of the thalamic network. Based on the above, the purpose of this study was to assess the electrophysiological and molecular effects of unilateral lesion of the globus pallidus on the electric activity of the thalamic reticular nucleus. Twomonthold male rats were used. The right globus pallidus was lesioned with quinolinic acid. Seven days after the lesion, ipsilateral turning was registered, confirming the lesion. Afterward, electrophysiological evaluation of the right thalamic reticular nucleus' electrical activity was performed. Subsequently, mRNA expression for D4 receptors and subunit α3, as well as protein content were assessed in the right reticular nucleus. Pallidum lesion caused an increase in firing frequency and decreased firing bursts of reticular neurons. In addition, dopaminergic D4 mRNA, as well as protein increased. In contrast, GABAergic GABAA subunit α3 expression was suppressed, but protein content increased. These results show that the globus pallidus regulates firing in reticular neurons through D4 receptors and subunit α3 of GABAA receptor in the reticular nucleus of the thalamus.
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Globo Pálido , Receptores de GABA-A , Animais , Masculino , Ratos , Potenciais de Ação/fisiologia , Globo Pálido/metabolismo , Neurônios/metabolismo , Ácido Quinolínico , Ratos Wistar , Receptores de Dopamina D4/metabolismo , Receptores de GABA-A/metabolismo , RNA Mensageiro/metabolismo , Núcleos Talâmicos/metabolismoRESUMO
Leishmaniasis represents a severe global health problem. In the last decades, there have been significant challenges in controlling this disease due to the unavailability of licensed vaccines, the high toxicity of the available drugs, and an unrestrained surge of drug-resistant parasites, and human immunodeficiency virus (HIV)-Leishmania co-infections. Leishmania spp. preferentially invade macrophage lineage cells of vertebrates for replication after subverting cellular functions of humans and other mammals. These early events in host-parasite interactions are likely to influence the future course of the disease. Thus, there is a continuing need to discover a simple cellular model that reproduces the in vivo pathogenesis. Acanthamoeba spp. are non-mammalian phagocytic amoeba with remarkable similarity to the cellular and functional aspects of macrophages. We aimed to assess whether the similarity reported between macrophages and Acanthamoeba spp. is sufficient to reproduce the infectivity of Leishmania spp. Herein, we analyzed co-cultures of Acanthamoeba castellanii or Acanthamoeba polyphaga with Leishmania infantum, Leishmania amazonensis, Leishmania major, and Leishmania braziliensis. Light and fluorescence microscopy revealed that the flagellated promastigotes attach to the A. castellanii and/or A. polyphaga in a bipolar and or random manner, which initiates their uptake via pseudopods. Once inside the cells, the promastigotes undergo significant changes, which result in the obligatory amastigote-like intracellular form. There was a productive infection with a continuous increase in intracellular parasites. However, we frequently observed intracellular amastigotes in vacuoles, phagolysosomes, and the cytosol of Acanthamoeba spp. Our findings corroborate that Leishmania spp. infects Acanthamoeba spp. and replicates in them but does not cause their rapid degeneration or lysis. Overall, the evidence presented here confirms that Acanthamoeba spp. have all prerequisites and can help elucidate how Leishmania spp. infect mammalian cells. Future work exposing the mechanisms of these interactions should yield novel insights into how these pathogens exploit amoebae.
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Acanthamoeba , Técnicas de Cocultura , Leishmania , Leishmaniose , Acanthamoeba/fisiologia , Leishmaniose/parasitologia , Leishmania/fisiologia , Humanos , Macrófagos/parasitologia , Interações Hospedeiro-Parasita , AnimaisRESUMO
BACKGROUND: Cadaveric skin grafts were initially used for the management of acute burn wounds. The biological coverage of the wound improves the quality of the wound bed, which prepares it to receive an autologous skin graft. The benefits of cadaveric skin graft in burn wounds have led to its use in the management of acute and chronic wounds of diverse etiologies. OBJECTIVE: To evaluate the use of cadaveric skin graft and subsequent autologous split-thickness skin graft (STSG) in the management of wounds of diverse etiologies at a single institution. MATERIALS AND METHODS: A retrospective analysis was performed of patients with wounds of different etiologies managed with cadaveric skin grafts followed by a second procedure in which autologous STSG was performed from May 2017 through May 2022 in the Plastic and Reconstructive Surgery Department of German Hospital, Buenos Aires, Argentina. RESULTS: A total of 25 patients with wounds of different etiologies were included. The mean affected body surface area (BSA) was 1.87%. The mean engraftment percentage of the cadaveric skin graft was 96.6%. The mean engraftment percentage of the STSG was 90.6%. All patients demonstrated improvement in local edema and inflammation, reduced secretions, and reduced pain after treatment. Two patients (8%) had complications, with 1 case of delayed healing of the donor site and 1 case of hypertrophic scarring. CONCLUSIONS: Cadaveric skin graft with subsequent STSG is a simple, safe, and effective alternative for the management of complex wounds of diverse etiologies. This technique is particularly useful in patients with multiple comorbidities who are at risk of recurrence and of developing multiple wounds during their lifetime.
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Cadáver , Transplante de Pele , Cicatrização , Humanos , Transplante de Pele/métodos , Estudos Retrospectivos , Masculino , Feminino , Cicatrização/fisiologia , Pessoa de Meia-Idade , Idoso , Adulto , Transplante Autólogo , Ferimentos e Lesões/cirurgia , Ferimentos e Lesões/terapia , Resultado do Tratamento , Queimaduras/terapia , Queimaduras/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Idoso de 80 Anos ou maisRESUMO
The theory of ecological speciation posits that adaptive divergence among incipient species raises incidental barriers to reproduction, thus catalyzing the emergence of new species. In this study, we conducted an experimental test of this theory in Galápagos finches, a clade in which beaks and mating songs are mechanistically linked. We forecasted the acoustic structure of songs for a set of possible evolutionary futures (successive droughts spurring increasingly large beaks) and, in a field assay, presented resulting song simulations to territorial males. We found that responses to songs dropped off after six simulated drought events, to degrees roughly comparable to drops in response to songs that diverged through cultural drift and acoustic adaptation. Our results support, in Darwin's finches, the feasibility and mechanistic bases of an ecological speciation hypothesis.
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Bico , Tentilhões , Especiação Genética , Vocalização Animal , Animais , Tentilhões/genética , Tentilhões/fisiologia , Masculino , Bico/anatomia & histologia , Equador , Secas , Feminino , Evolução Biológica , Comportamento Sexual AnimalRESUMO
STUDY DESIGN: Experimental study utilizing with a standardized model (MASCIS Impactor) of Spinal Cord Injury (SCI) in Balb C mouse model with implantation of mononuclear stem cells derived from the human umbilical cord and placenta blood in the early chronic phase of SCI. OBJECTIVES: The aim of this study was to evaluate the nerve regeneration and motor functional recovery in Balb C mice with surgically induced paraplegia in response to the use of mononuclear stem cells, in early chronic phase (> 2 weeks and < 6 months), because there is yet potential of neuronal and functional recovery as the neuronal scar is not still completely established. METHODS: Forty-eight mice were randomly assigned to 6 groups of 8 animals. Group 1 received the stem cells 3 weeks after the trauma, and Group 2 received them six weeks later. In Group 3, saline solution was injected at the site of the lesion 3 weeks after the trauma, and in Group 4, 6 weeks later. Group 5 underwent only spinal cord injury and Group 6 underwent laminectomy only. The scales used for motor assessment were BMS and MFS for 12 weeks. RESULTS: The intervention groups showed statistically significant motor improvement. In the histopathological analysis, the intervention groups had a lower degree of injury (p < 0.05). Regarding axonal budding, the intervention groups showed increasing in axonal budding in the caudal portion (p < 0.05). CONCLUSIONS: The use of stem cells in mice in the chronic phase after 3 and 6 weeks of SCI brings functional and histopathological benefits to them.
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Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Regeneração Nervosa , Placenta , Distribuição Aleatória , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal , Animais , Traumatismos da Medula Espinal/fisiopatologia , Feminino , Camundongos , Humanos , Gravidez , Fatores de Tempo , Regeneração Nervosa/fisiologia , Paraplegia/fisiopatologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Atividade Motora/fisiologia , Cordão Umbilical/citologia , MasculinoRESUMO
Sarcopenia is characterized by a decline in muscle strength, generalized loss of skeletal muscle mass, and impaired physical performance, which are common outcomes used to screen, diagnose, and determine severity of sarcopenia in older adults. These outcomes are associated with poor quality of life, increased risk of falls, hospitalization, and mortality in this population. The development of sarcopenia is underpinned by aging, but other factors can lead to sarcopenia, such as chronic diseases, physical inactivity, inadequate dietary energy intake, and reduced protein intake (nutrition-related sarcopenia), leading to an imbalance between muscle protein synthesis and muscle protein breakdown. Protein digestion and absorption are also modified with age, as well as the reduced capacity of metabolizing protein, hindering older adults from achieving ideal protein consumption (i.e., 1-1.5 g/kg/day). Nutritional supplement strategies, like animal (i.e., whey protein) and plant-based protein, leucine, and creatine have been shown to play a significant role in improving outcomes related to sarcopenia. However, the impact of other supplements (e.g., branched-chain amino acids, isolated amino acids, and omega-3) on sarcopenia and related outcomes remain unclear. This narrative review will discuss the evidence of the impact of these nutritional strategies on sarcopenia outcomes in older adults.
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Suplementos Nutricionais , Sarcopenia , Humanos , Sarcopenia/dietoterapia , Sarcopenia/prevenção & controle , Sarcopenia/metabolismo , Idoso , Músculo Esquelético/metabolismo , Envelhecimento/fisiologia , Proteínas Alimentares/administração & dosagem , Força Muscular , Qualidade de Vida , Idoso de 80 Anos ou mais , Proteínas Musculares/metabolismoRESUMO
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB) was first identified in 1882 by Robert Koch, and it is estimated that this pathogen has been around for as long as 3 million years.The World Health Organization (WHO) reported that in 2022 alone an estimated 10.6 million people developed TB worldwide, making TB the world's second leading cause of death from a single infectious agent, just after coronavirus disease (COVID-19), despite TB being a preventable and usually curable disease.Moreover, epidemiological studies suggest that approximately a quarter of the global population has been infected with TB bacteria, of which 5-10% will eventually develop symptoms and TB disease. Poverty, obesity, diabetes, and alcohol use contribute to the burden of TB.Alveolar macrophages play a pivotal role in the clearance of airborne pathogenic microorganisms and are the primary target of M. tuberculosis.Macrophage activity depend on metabolism and circadian rhythmicity, and mitochondria are a central hub that coordinates the communication between metabolism, circadian rhythmicity, and the immune system.Recent evidence has thrown light on how M. tuberculosis metabolism may regulate macrophage activity and the overall host responses to M. tuberculosis infection.This chapter explores how all these biological domains relate to each other, highlighting the multidimensional nature of TB, and positioning macrophages at center stage.
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Ritmo Circadiano , Macrófagos , Mitocôndrias , Mycobacterium tuberculosis , Tuberculose , Humanos , Tuberculose/imunologia , Ritmo Circadiano/fisiologia , Mitocôndrias/metabolismo , Macrófagos/microbiologia , Macrófagos/metabolismo , Macrófagos/imunologia , AnimaisRESUMO
Robotic walking devices can be used for intensive exercises to enhance gait rehabilitation therapies. Mixed Reality (MR) techniques may improve engagement through immersive and interactive environments. This article introduces an MR-based multimodal human-robot interaction strategy designed to enable shared control with a Smart Walker. The MR system integrates virtual and physical sensors to (i) enhance safe navigation and (ii) facilitate intuitive mobility training in personalized virtual scenarios by using an interface with three elements: an arrow to indicate where to go, laser lines to indicate nearby obstacles, and an ellipse to show the activation zone. The multimodal interaction is context-based; the presence of nearby individuals and obstacles modulates the robot's behavior during navigation to simplify collision avoidance while allowing for proper social navigation. An experiment was conducted to evaluate the proposed strategy and the self-explanatory nature of the interface. The volunteers were divided into four groups, with each navigating under different conditions. Three evaluation methods were employed: task performance, self-assessment, and observational measurement. Analysis revealed that participants enjoyed the MR system and understood most of the interface elements without prior explanation. Regarding the interface, volunteers who did not receive any introductory explanation about the interface elements were mostly able to guess their purpose. Volunteers that interacted with the interface in the first session provided more correct answers. In future research, virtual elements will be integrated with the physical environment to enhance user safety during navigation, and the control strategy will be improved to consider both physical and virtual obstacles.
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Robótica , Realidade Virtual , Humanos , Robótica/métodos , Masculino , Feminino , Caminhada/fisiologia , Interface Usuário-Computador , Adulto , Adulto Jovem , Marcha/fisiologiaRESUMO
Currently, the number of vehicles in circulation continues to increase steadily, leading to a parallel increase in vehicular accidents. Among the many causes of these accidents, human factors such as driver drowsiness play a fundamental role. In this context, one solution to address the challenge of drowsiness detection is to anticipate drowsiness by alerting drivers in a timely and effective manner. Thus, this paper presents a Convolutional Neural Network (CNN)-based approach for drowsiness detection by analyzing the eye region and Mouth Aspect Ratio (MAR) for yawning detection. As part of this approach, endpoint delineation is optimized for extraction of the region of interest (ROI) around the eyes. An NVIDIA Jetson Nano-based device and near-infrared (NIR) camera are used for real-time applications. A Driver Drowsiness Artificial Intelligence (DD-AI) architecture is proposed for the eye state detection procedure. In a performance analysis, the results of the proposed approach were compared with architectures based on InceptionV3, VGG16, and ResNet50V2. Night-Time Yawning-Microsleep-Eyeblink-Driver Distraction (NITYMED) was used for training, validation, and testing of the architectures. The proposed DD-AI network achieved an accuracy of 99.88% with the NITYMED test data, proving superior to the other networks. In the hardware implementation, tests were conducted in a real environment, resulting in 96.55% and 14 fps on average for the DD-AI network, thereby confirming its superior performance.
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Condução de Veículo , Redes Neurais de Computação , Humanos , Boca/fisiologia , Olho , Fases do Sono/fisiologia , Sonolência , Inteligência Artificial , Acidentes de TrânsitoRESUMO
Oximeters have significantly evolved since their invention and are essential for monitoring chronic diseases in home care. However, commercial models can present an economic barrier. Therefore, we conducted a review of the use of low-cost pulse oximeters in the home care of patients with respiratory diseases. Our review included studies addressing oxygen saturation and heart rate monitoring in adults, focusing on the use of portable devices. Our search identified advances in vital signs monitoring that could provide accessible solutions for non-clinical settings. Although there are challenges related to clinical validation and accuracy, these oximeters may improve medical care, particularly in resource-limited areas. As a result, the accessibility of these devices opens up new possibilities for patients with chronic respiratory diseases in home care, enabling regular self-monitoring and increasing control over their health.
Assuntos
Serviços de Assistência Domiciliar , Oximetria , Humanos , Oximetria/instrumentação , Oximetria/métodos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Frequência Cardíaca/fisiologia , Saturação de Oxigênio/fisiologiaRESUMO
Effective pest population monitoring is crucial in precision agriculture, which integrates various technologies and data analysis techniques for enhanced decision-making. This study introduces a novel approach for monitoring lures in traps targeting the Mediterranean fruit fly, utilizing air quality sensors to detect total volatile organic compounds (TVOC) and equivalent carbon dioxide (eCO2). Our results indicate that air quality sensors, specifically the SGP30 and ENS160 models, can reliably detect the presence of lures, reducing the need for frequent physical trap inspections and associated maintenance costs. The ENS160 sensor demonstrated superior performance, with stable detection capabilities at a predefined distance from the lure, suggesting its potential for integration into smart trap designs. This is the first study to apply TVOC and eCO2 sensors in this context, paving the way for more efficient and cost-effective pest monitoring solutions in smart agriculture environments.