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1.
Eur J Appl Physiol ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259396

RESUMO

Compared to the determination of exercise thresholds based on systemic changes in blood lactate concentrations or gas exchange data, the determination of breakpoints based on muscle oxygen saturation offers a valid alternative to provide specific information on muscle-derived thresholds. Our study explored the profiles and timing of the second muscle oxygenation threshold (MOT2) in different muscles. Twenty-six cyclists and triathletes (15 male: age = 23 ± 7 years, height = 178 ± 5 cm, body mass = 70.2 ± 5.3 kg; 11 female: age = 22 ± 4 years, height = 164 ± 4 cm, body mass = 58.3 ± 8.1 kg) performed a graded exercise test (GXT), on a cycle ergometer. Power output, blood lactate concentration, heart rate, rating of perceived exertion, skinfolds and muscle oxygen saturation were registered in five muscles (vastus lateralis, biceps femoris, gastrocnemius medialis, tibialis anterior and triceps brachii) and percentage at which MOT2 occurred for each muscle was determinated using the Exponential Dmax. The results of Statistical Parametric Mapping and ANOVA showed that, although muscle oxygenation displayed different profiles in each muscle during a GXT, MOT2 occurred at a similar percentage of the GXT in each muscle (77% biceps femoris, 75% tibalis anterior, 76% gastrocnemius medialis and 72% vastus lateralis) and it was similar that systemic threshold (73% of the GXT). In conclusion, this study showed different profiles of muscle oxygen saturation in different muscles, but without notable differences in the timing for MOT2 and concordance with systemic threshold. Finally, we suggest the analysis of the whole signal and not to simplify it to a breakpoint.

2.
Neurotherapeutics ; 21(1): e00301, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241160

RESUMO

Oxidative stress and neuroinflammation are major contributors to the pathophysiology of ALS. Nicotinamide riboside (a NAD+ precursor) and pterostilbene (a natural antioxidant) were efficacious in a human pilot study of ALS patients and in ALS SOD1G93A transgenic mice. Ibudilast targets different phosphodiesterases and the macrophage migration inhibitory factor, reduces neuroinflammation, and in early-phase studies improved survival and slowed progression in ALS patients. Using two ALS murine models (SOD1G93A, FUSR521C) the effects of nicotinamide riboside, pterostilbene, and ibudilast on disease onset, progression and survival were studied. In both models ibudilast enhanced the effects of nicotinamide riboside and pterostilbene on survival and neuromotor functions. The triple combination reduced microgliosis and astrogliosis, and the levels of different proinflammatory cytokines in the CSF. TNFα, IFNγ and IL1ß increased H2O2 and NO generation by motor neurons, astrocytes, microglia and endothelial cells isolated from ALS mice. Nicotinamide riboside and pterostilbene decreased H2O2 and NO generation in all these cells. Ibudilast specifically decreased TNFα levels and H2O2 generation by microglia and endothelial cells. Unexpectedly, pathophysiological concentrations of H2O2 or NO caused minimal motor neuron cytotoxicity. H2O2-induced cytotoxicity was increased by NO via a trace metal-dependent formation of potent oxidants (i.e. OH and -OONO radicals). In conclusion, our results show that the combination of nicotinamide riboside, pterostilbene and ibudilast improve neuromotor functions and survival in ALS murine models. Studies on the underlying mechanisms show that motor neuron protection involves the decrease of oxidative and nitrosative stress, the combination of which is highly damaging to motor neurons.


Assuntos
Esclerose Lateral Amiotrófica , Indolizinas , Niacinamida/análogos & derivados , Pirazóis , Compostos de Piridínio , Camundongos , Animais , Humanos , Superóxido Dismutase-1 , Esclerose Lateral Amiotrófica/tratamento farmacológico , Doenças Neuroinflamatórias , Fator de Necrose Tumoral alfa , Células Endoteliais , Peróxido de Hidrogênio , Projetos Piloto , Neurônios Motores , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Camundongos Transgênicos , Modelos Animais de Doenças , Superóxido Dismutase , Medula Espinal
3.
Physiol Meas ; 44(12)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38081136

RESUMO

Objective. Threshold determination for improving training and sports performance is important for researchers and trainers, who currently use different methods for determining lactate, ventilatory or muscle oxygenation (SmO2) thresholds. Our study aimed to compare the identification of the intensity at the first and second thresholds using lactate and SmO2data by different mathematical methods in different muscles during a graded cycling test.Approach. Twenty-six cyclists (15 males and 11 females; 23 ±6 years, 1.71 ± 0.09 m, 64.3 ± 8.8 Kg and 12 ± 3 training hours per week) performed a graded test on the cycle ergometer. Power output and saturation of muscle oxygen in four muscles (vastus lateralis, biceps femoris, gastrocnemius and tibialis anterior) were measured, along with systemic lactate concentration.Main Results. Our results showed that any method was reliable for determining the first muscle oxygenation threshold (MOT1) when comparing the lactate threshold in any muscle. However, the best method for determining the second muscle oxygenation threshold (MOT2) was the Exp-Dmax (p< 0.01; ICC = 0.79-0.91) in all muscles. In particular, the vastus lateralis muscle showed the highest intraclass correlation coefficient (ICC = 0.91, CI95% [0.81, 0.96]). However, results varied per sex across all muscles analyzed.Significance. Although the first muscle oxygenation threshold could not be determined using mathematical methods in all the muscles analyzed, the Exp-Dmax method presented excellent results in detecting the second systemic threshold in the vastus lateralis.


Assuntos
Desempenho Atlético , Ácido Láctico , Masculino , Feminino , Humanos , Músculo Esquelético/fisiologia , Ciclismo/fisiologia , Músculo Quadríceps
4.
J Appl Physiol (1985) ; 135(5): 1092-1101, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37732376

RESUMO

Although in recent years near-infrared spectroscopy has been used in many sports to monitor muscle oxygen saturation (SmO2), there is a lack of knowledge about the sex differences in SmO2 during exercise in different muscles. Our study aimed to examine SmO2 differences in muscles between female and male cyclists, during a graded cycling test and at the first and second lactate thresholds. Twenty-five trained cyclists and triathletes (15 males: 23 ± 7 yr, 1.78 ± 0.05 m, 70.2 ± 5.3 kg, and 10 females: 22 ± 5 yr, 1.64 ± 0.06 m, 58 ± 8 kg) performed a graded cycling test on the cycle ergometer. Power output and SmO2 in five muscles (dominant vastus lateralis, tibialis anterior, gastrocnemius medial, biceps femoris, and triceps brachii) were measured. Our mixed regression models showed that the interaction between power output and sex was significant for all the muscles analyzed (P < 0.001), indicating a greater decrease in SmO2 for males as power output increased. Moreover, the statistical parametric mapping analyses showed for females higher SmO2 in the middle of the test in biceps femoris (P = 0.03), gastrocnemius medial (P = 0.02), and tibialis anterior (P = 0.04). Finally, the males presented a lower SmO2 in all muscles where the second lactate threshold occurred, with greater evidence than in the first lactate threshold. In conclusion, females have higher SmO2 in all muscles, and these differences are more noticeable during the graded cycling test, such that males seem to have a greater reliance on oxygen extraction than females for a given relative intensity of exercise.NEW & NOTEWORTHY This study investigated the profiles of muscle oxygen saturation (SmO2) during incremental exercise in females and males. Females presented higher overall SmO2 than males during moderate and heavy intensity domain exercise in all muscles including muscles that are not mainly involved in pedaling (triceps brachii), from those that are stabilizers (medial gastrocnemius, tibialis anterior, and biceps femoris), to those that are related to power output production (vastus lateralis).


Assuntos
Saturação de Oxigênio , Caracteres Sexuais , Masculino , Humanos , Feminino , Músculo Esquelético/fisiologia , Músculo Quadríceps , Ácido Láctico , Teste de Esforço , Consumo de Oxigênio , Oxigênio/metabolismo
5.
Sci Rep ; 13(1): 12649, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542055

RESUMO

Over the last few years, portable Near-Infrared Spectroscopy (NIRS) technology has been suggested for determining metabolic/ventilator thresholds. This systematic review and meta-analysis aimed to assess the reliability of a portable muscle oxygenation monitor for determining thresholds during exercise testing. The proposed PICO question was: Is the exercise intensity of muscle oxygenation thresholds, using portable NIRS, reliable compared with lactate and ventilatory thresholds for exercise intensity determined in athletes? A search of Pubmed, Scopus and Web of Science was undertaken and the review was conducted following PRISMA guidelines. Fifteen articles were included. The domains which presented the highest biases were confounders (93% with moderate or high risk) and participant selection (100% with moderate or high risk). The intra-class correlation coefficient between exercise intensity of the first ventilatory or lactate threshold and the first muscle oxygenation threshold was 0.53 (obtained with data from only 3 studies), whereas the second threshold was 0.80. The present work shows that although a portable muscle oxygenation monitor has moderate to good reliability for determining the second ventilatory and lactate thresholds, further research is necessary to investigate the mathematical methods of detection, the capacity to detect the first threshold, the detection in multiple regions, and the effect of sex, performance level and adipose tissue in determining thresholds.


Assuntos
Exercício Físico , Músculo Esquelético , Humanos , Reprodutibilidade dos Testes , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Tecido Adiposo/metabolismo , Ácido Láctico/metabolismo , Consumo de Oxigênio/fisiologia , Teste de Esforço/métodos
6.
Cancers (Basel) ; 15(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37444524

RESUMO

At present, the applications and efficacy of non-ionizing radiations (NIR) in oncotherapy are limited. In terms of potential combinations, the use of biocompatible magnetic nanoparticles as heat mediators has been extensively investigated. Nevertheless, developing more efficient heat nanomediators that may exhibit high specific absorption rates is still an unsolved problem. Our aim was to investigate if externally applied magnetic fields and a heat-inducing NIR affect tumor cell viability. To this end, under in vitro conditions, different human cancer cells (A2058 melanoma, AsPC1 pancreas carcinoma, MDA-MB-231 breast carcinoma) were treated with the combination of electromagnetic fields (EMFs, using solenoids) and hyperthermia (HT, using a thermostated bath). The effect of NIR was also studied in combination with standard chemotherapy and targeted therapy. An experimental device combining EMFs and high-intensity focused ultrasounds (HIFU)-induced HT was tested in vivo. EMFs (25 µT, 4 h) or HT (52 °C, 40 min) showed a limited effect on cancer cell viability in vitro. However, their combination decreased viability to approximately 16%, 50%, and 21% of control values in A2058, AsPC1, and MDA-MB-231 cells, respectively. Increased lysosomal permeability, release of cathepsins into the cytosol, and mitochondria-dependent activation of cell death are the underlying mechanisms. Cancer cells could be completely eliminated by combining EMFs, HT, and standard chemotherapy or EMFs, HT, and anti-Hsp70-targeted therapy. As a proof of concept, in vivo experiments performed in AsPC1 xenografts showed that a combination of EMFs, HIFU-induced HT, standard chemotherapy, and a lysosomal permeabilizer induces a complete cancer regression.

7.
J Therm Biol ; 113: 103523, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37055127

RESUMO

PURPOSE: There are no previous studies developing machine learning algorithms in the classification of lumbar sympathetic blocks (LSBs) performance using infrared thermography data. The objective was to assess the performance of different machine learning algorithms to classify LSBs carried out in patients diagnosed with lower limbs Complex Regional Pain Syndrome as successful or failed based on the evaluation of thermal predictors. METHODS: 66 LSBs previously performed and classified by the medical team were evaluated in 24 patients. 11 regions of interest on each plantar foot were selected within the thermal images acquired in the clinical setting. From every region of interest, different thermal predictors were extracted and analysed in three different moments (minutes 4, 5, and 6) along with the baseline time (just after the injection of a local anaesthetic around the sympathetic ganglia). Among them, the thermal variation of the ipsilateral foot and the thermal asymmetry variation between feet at each minute assessed and the starting time for each region of interest, were fed into 4 different machine learning classifiers: an Artificial Neuronal Network, K-Nearest Neighbours, Random Forest, and a Support Vector Machine. RESULTS: All classifiers presented an accuracy and specificity higher than 70%, sensitivity higher than 67%, and AUC higher than 0.73, and the Artificial Neuronal Network classifier performed the best with a maximum accuracy of 88%, sensitivity of 100%, specificity of 84% and AUC of 0.92, using 3 predictors. CONCLUSION: These results suggest thermal data retrieved from plantar feet combined with a machine learning-based methodology can be an effective tool to automatically classify LSBs performance.


Assuntos
Algoritmos , Aprendizado de Máquina , Humanos , Algoritmo Florestas Aleatórias , Máquina de Vetores de Suporte
8.
Cells ; 12(3)2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36766760

RESUMO

Circulating glucocorticoids increase during stress. Chronic stress, characterized by a sustained increase in serum levels of cortisol, has been associated in different cases with an increased risk of cancer and a worse prognosis. Glucocorticoids can promote gluconeogenesis, mobilization of amino acids, fat breakdown, and impair the body's immune response. Therefore, conditions that may favor cancer growth and the acquisition of radio- and chemo-resistance. We found that glucocorticoid receptor knockdown diminishes the antioxidant protection of murine B16-F10 (highly metastatic) melanoma cells, thus leading to a drastic decrease in their survival during interaction with the vascular endothelium. The BRAFV600E mutation is the most commonly observed in melanoma patients. Recent studies revealed that VMF/PLX40-32 (vemurafenib, a selective inhibitor of mutant BRAFV600E) increases mitochondrial respiration and reactive oxygen species (ROS) production in BRAFV600E human melanoma cell lines. Early-stage cancer cells lacking Nrf2 generate high ROS levels and exhibit a senescence-like growth arrest. Thus, it is likely that a glucocorticoid receptor antagonist (RU486) could increase the efficacy of BRAF-related therapy in BRAFV600E-mutated melanoma. In fact, during early progression of skin melanoma metastases, RU486 and VMF induced metastases regression. However, treatment at an advanced stage of growth found resistance to RU486 and VMF. This resistance was mechanistically linked to overexpression of proteins of the Bcl-2 family (Bcl-xL and Mcl-1 in different human models). Moreover, melanoma resistance was decreased if AKT and NF-κB signaling pathways were blocked. These findings highlight mechanisms by which metastatic melanoma cells adapt to survive and could help in the development of most effective therapeutic strategies.


Assuntos
Antioxidantes , Melanoma , Animais , Humanos , Camundongos , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Melanoma/patologia , Mifepristona/farmacologia , Fator 2 Relacionado a NF-E2 , Proteínas Proto-Oncogênicas B-raf/genética , Espécies Reativas de Oxigênio/uso terapêutico , Receptores de Glucocorticoides
9.
J Adv Res ; 45: 73-86, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35599107

RESUMO

INTRODUCTION: Effective agents that could confer long-term protection against ionizing radiation in vivo would have applications in medicine, biotechnology, and in air and space travel. However, at present, drugs that can effectively protect against lethal ionizing radiations are still an unmet need. OBJECTIVE: To investigate if combinations of natural polyphenols, known for their antioxidant potential, could protect against ionizing radiations. METHODS: Plant-derived polyphenols were screened for their potential ability to confer radioprotection to mice given a lethal whole-body γ radiation (137Cs) dose expected to kill 50% of the animals in 30 days. Telomere and centromere staining, Q-FISH and comet assays were used to investigate chromosomal aberration, micronuclei formation and DNA breaks. Molecular oxidations were investigated by enzyme immunoassays and UPLC-MS/MS. RT-PCR, western blotting and siRNA-induced gene silencing were used to study signaling mechanisms and molecular interactions. RESULTS: The combination of pterostilbene (PT) and silibinin (SIL) was the most effective against γ-irradiation, resulting in 100% of the mice surviving at 30 days and 20% survival at one year. Treatment post γ-irradiation with two potential radiomitigators nicotinamide riboside (NR, a vitamin B3 derivative), and/or fibroblast-stimulating lipoprotein 1 (FSL1, a toll-like receptor 2/6 agonist), did not extend survival. However, the combination of PT, SIL, NR and FSL1 achieved a 90% survival one year post γ-irradiation. The mechanism involves induction of the Nrf2-dependent cellular antioxidant defense, reduction of NF-kB signaling, upregulation of the PGC-1α/sirtuins 1 and 3 axis, PARP1-dependent DNA repair, and stimulation of hematopoietic cell recovery. The pathway linking Nrf2, sirtuin 3 and SOD2 is key to radioprotection. Importantly, this combination did not interfere with X-ray mediated killing of different tumor cells in vivo. CONCLUSION: The combination of the radioprotectors PT and SIL with the radiomitigators NR and FSL1 confer effective, long-term protection against γ radiation in vivo. This strategy is potentially capable of protecting mammals against ionizing radiations.


Assuntos
NAD , Protetores contra Radiação , Camundongos , Animais , Raios gama , Antioxidantes , Receptor 2 Toll-Like/agonistas , Lipopeptídeos , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico , Polifenóis/farmacologia , Fator 2 Relacionado a NF-E2 , Cromatografia Líquida , Ligantes , Espectrometria de Massas em Tandem , Mamíferos
10.
Sensors (Basel) ; 22(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366270

RESUMO

Valencian handball consists in hitting the ball with the hands and it may contribute to injury development on the hands. This study aimed to analyze skin temperature asymmetries and recovery after a cold stress test (CST) in professional players of Valencian handball before and after a competition. Thirteen professional athletes and a control group of ten physically active participants were measured. For both groups, infrared images were taken at the baseline condition; later they underwent a thermal stress test (pressing for 2 min with the palm of the hand on a metal plate) and then recovery images were taken. In athletes, the images were also taken after their competition. Athletes at baseline condition presented lower temperatures (p < 0.05) in the dominant hand compared with the non-dominant hand. There were asymmetries in all regions after their match (p < 0.05). After CST, a higher recovery rate was found after the game. The regions with the most significant differences in variation, asymmetries and recovery patterns were the index, middle and ring fingers, and the palm of the dominant hand. Taking into account that lower temperatures and the absence of temperature variation may be the consequence of a vascular adaptation, thermography could be used as a method to prevent injuries in athletes from Valencian handball.


Assuntos
Temperatura Cutânea , Esportes , Humanos , Mãos/irrigação sanguínea , Atletas , Termografia
11.
Biol Sport ; 39(4): 895-903, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36247937

RESUMO

This study aimed to compare intraocular pressure (IOP), mean ocular perfusion pressure (MOPP) and central corneal thickness (CCT) acute adaptations to squat exercise using elastic bands (EB) or weight plates (WP) together with the weight of the bar and applying maximal or submaximal efforts. Cardiovascular parameters (pulse pressure, mean blood pressure, heart rate), rate of perceived exertion, kilograms, and number of repetitions served to monitor psychophysiological acute variations. Twenty physically active males (25.55 ± 4.75 y.o.) underwent two sessions (one for familiarization and one for the experimental trial). In the experimental session, ocular and cardiovascular pre-exercise measurements were taken. Then, two sets using WP and two using EB attached to the bar with the same load were performed by each subject in random order. Immediately after finishing each set, the subjects rated perceived exertion, and cardiovascular and ocular measurements were taken, in this order. An ANOVA with post-hoc LSD evaluated differences between sets. IOP significantly decreased (p < 0.001, ƞp2 = 0.513), and MOPP (p < 0.001, ƞp2 = 0.413) and cardiovascular variables significantly increased due to the exercise effect; CCT changes were non-significant. No significant effect of the material, level of effort, or their interaction was observed in the IOP and MOPP (p > 0.05). EB permitted more repetitions to be performed and led to non-significantly lower post-exercise IOP values (effect size [d] compared to resting 0.79 and 1.00) in comparison to WP (d = 0.73-0.74). IOP and ocular and systemic hemodynamic responses are similar when using EB instead of WP to load the bar, with EB allowing a larger number of repetitions. Data presented in this paper may help with the prescription of resistance training for people with glaucoma risk factors.

12.
Cancers (Basel) ; 14(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35892873

RESUMO

N-acetylcysteine (NAC) is a direct Cys donor and a promoter of glutathione (GSH) synthesis. GSH regulates melanoma growth and NAC has been suggested to increase melanoma metastases in mice. We found that high therapeutic doses of NAC do not increase the growth of melanoma xenografts, but can cause metastatic spread and distant metastases. Nevertheless, this is not due to an antioxidant effect since NAC, in fact, increases the generation of reactive oxygen species in the growing metastatic melanoma. Trolox, an antioxidant vitamin E derivative, administered in vivo, decreased metastatic growth. Metastatic cells isolated from NAC-treated mice showed an increase in the nuclear translocation of Nrf2, as compared to controls. Nrf2, a master regulator of the antioxidant response, controls the expression of different antioxidant enzymes and of the γ-glutamylcysteine ligase (the rate-limiting step in GSH synthesis). Cystine uptake through the xCT cystine-glutamate antiporter (generating intracellular Cys) and the γ-glutamylcysteine ligase activity are key to control metastatic growth. This is associated to an increase in the utilization of L-Gln by the metastatic cells, another metastases promoter. Our results demonstrate the potential of NAC as an inducer of melanoma metastases spread, and suggest that caution should be taken when administering GSH promoters to cancer patients.

13.
Antioxidants (Basel) ; 11(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35739995

RESUMO

Atomic and radiological crises can be caused by accidents, military activities, terrorist assaults involving atomic installations, the explosion of nuclear devices, or the utilization of concealed radiation exposure devices. Direct damage is caused when radiation interacts directly with cellular components. Indirect effects are mainly caused by the generation of reactive oxygen species due to radiolysis of water molecules. Acute and persistent oxidative stress associates to radiation-induced biological damages. Biological impacts of atomic radiation exposure can be deterministic (in a period range a posteriori of the event and because of destructive tissue/organ harm) or stochastic (irregular, for example cell mutation related pathologies and heritable infections). Potential countermeasures according to a specific scenario require considering basic issues, e.g., the type of radiation, people directly affected and first responders, range of doses received and whether the exposure or contamination has affected the total body or is partial. This review focuses on available medical countermeasures (radioprotectors, radiomitigators, radionuclide scavengers), biodosimetry (biological and biophysical techniques that can be quantitatively correlated with the magnitude of the radiation dose received), and strategies to implement the response to an accidental radiation exposure. In the case of large-scale atomic or radiological events, the most ideal choice for triage, dose assessment and victim classification, is the utilization of global biodosimetry networks, in combination with the automation of strategies based on modular platforms.

14.
J Therm Biol ; 105: 103225, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35393059

RESUMO

Skin temperature assessment has received much attention as a possible measurement of physiological response against stress produced by exercise and research studies usually measure skin temperature 24 or 48 h after exercise. Scientific evidence about skin temperature evolution during the 24-h period immediately after exercising is, however, scarce. The aim was to assess the effect of a 10 km run at moderate intensity on baseline skin temperature and thermal response after a cold stress test during that 24 h period. Fourteen participants were measured before, immediately after, and at 2, 5, 9 and 24 h after a 10 km run at a perceived exertion rate of 11 points (max 20 points). Fourteen control participants who undertook no exercise were also measured during that day. The measurements included muscle pain and fatigue perception, reactive oxygen species, heart rate variability, skin temperature of the lower limbs, and skin temperature after cold stress test. Exercise resulted in a skin temperature increase (e.g., 0.5-1.3 °C of posterior leg 9 h after exercise) and this effect continued in some regions (0.4-0.9 °C of posterior leg) over that 24 h period. However, the thermal response to the cold stress test remained the same (p > 0.05). In conclusion, 10 km aerobic running exercise results in a skin temperature increase, peaking at between 5 and 9 h after exercise, but does not alter the thermal response to a cold stress test. This study provides a sound basis for post-exercise skin temperature response that can be used as a setting-off point for comparisons with future studies that analyze greater muscle damage.


Assuntos
Corrida , Temperatura Cutânea , Temperatura Baixa , Resposta ao Choque Frio , Teste de Esforço , Humanos , Extremidade Inferior , Corrida/fisiologia
15.
Angle Orthod ; 92(4): 505-511, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35275982

RESUMO

OBJECTIVES: To evaluate the relationship between dental malocclusion and speech to understand the etiology of speech sound disorders (SSD) in schoolchildren and to make a correct diagnosis and treatment plan. MATERIALS AND METHODS: Articulation and dental occlusion, oromyofunctional evaluation with orofacial praxis and musculature, resting tongue position, and swallowing pattern were analyzed in 290 schoolchildren between the ages of 4 and 7 years. Statistical tests were considered significant for P < .05. RESULTS: A significant association between dental malocclusions (Angle Class II and III, anterior open bite, edge-to-edge bite, overjet and anterior crossbite) and phonetic alterations (P = .008) was observed. Sigmatisms and rhotacisms were the most frequent disorders. Malocclusions also showed a significant association with oral habits and with orofacial praxis and muscle activity. CONCLUSIONS: The presence of malocclusion can cause imbalances in the functions involved in the stomatognathic system. Awareness of this relationship in young children would help professionals to implement preventive measures for the optimum development of children's oral health.


Assuntos
Má Oclusão Classe II de Angle , Má Oclusão , Mordida Aberta , Sobremordida , Criança , Pré-Escolar , Humanos , Má Oclusão/etiologia , Má Oclusão Classe II de Angle/complicações , Sobremordida/complicações , Prevalência , Hábitos Linguais/efeitos adversos
16.
Antioxidants (Basel) ; 10(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34943110

RESUMO

Oxidative stress has been proposed as a major mechanism of damage to motor neurons associated with the progression of amyotrophic lateral sclerosis (ALS). Astrocytes are the most numerous glial cells in the central nervous system and, under physiological conditions, protect neurons from oxidative damage. However, it is uncertain how their reactive phenotype may affect motor neurons during ALS progression. In two different ALS mouse models (SOD1G93A and FUS-R521C), we found that increased levels of proinflammatory interleukin 6 facilitate glutathione (GSH) release from the liver to blood circulation, which can reach the astrocytes and be channeled towards motor neurons as a mechanism of antioxidant protection. Nevertheless, although ALS progression is associated with an increase in GSH efflux from astrocytes, generation of reactive oxygen species also increases, suggesting that as the disease progresses, astrocyte-derived oxidative stress could be key to motor-neuron damage.

17.
Biomedicines ; 9(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34440204

RESUMO

Charcot first described amyotrophic lateral sclerosis (ALS) between 1865 and 1874 as a sporadic adult disease resulting from the idiopathic progressive degeneration of the motor neuronal system, resulting in rapid, progressive, and generalized muscle weakness and atrophy. There is no cure for ALS and no proven therapy to prevent it or reverse its course. There are two drugs specifically approved for the treatment of ALS, riluzol and edaravone, and many others have already been tested or are following clinical trials. However, at the present moment, we still cannot glimpse a true breakthrough in the treatment of this devastating disease. Nevertheless, our understanding of the pathophysiology of ALS is constantly growing. Based on this background, we know that oxidative stress, alterations in the NAD+-dependent metabolism and redox status, and abnormal mitochondrial dynamics and function in the motor neurons are at the core of the problem. Thus, different antioxidant molecules or NAD+ generators have been proposed for the therapy of ALS. This review analyzes these options not only in light of their use as individual molecules, but with special emphasis on their potential association, and even as part of broader combined multi-therapies.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34444044

RESUMO

The objective of this preliminary study was to determine the reproducibility of lower limbs skin temperature after cold stress test using the Game Ready system. Skin temperature of fourteen participants was measured before and after cold stress test using the Game Ready system and it was repeated the protocol in four times: at 9:00, at 11:00, at 19:00, and at 9:00 h of the posterior day. To assess skin temperature recovery after cold stress test, a logarithmic equation for each region was calculated, and constant (ß0) and slope (ß1) coefficients were obtained. Intraclass correlation coefficient (ICC), standard error (SE), and within-subject coefficient of variation (CV) were determined. No differences were observed between measurement times in any of the regions for the logarithmic coefficients (p > 0.38). Anterior thigh (ß0 ICC 0.33-0.47; ß1 ICC 0.31-0.43) and posterior knee (ß0 ICC 0.42-0.58; ß1 ICC 0.28-0.57) were the regions with the lower ICCs, and the other regions presented values with a fair and good reproducibility (ICC > 0.41). Posterior leg was the region with the better reproducibility (ß0 ICC 0.68-0.78; ß1 ICC 0.59-0.74; SE 3-4%; within-subject CV 7-12%). In conclusion, cold stress test using Game Ready system showed a fair and good reproducibility, especially when the posterior leg was the region assessed.


Assuntos
Resposta ao Choque Frio , Temperatura Cutânea , Temperatura Baixa , Teste de Esforço , Humanos , Reprodutibilidade dos Testes
19.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198557

RESUMO

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disease of the motor system. It is characterized by the degeneration of both upper and lower motor neurons, which leads to muscle weakness and paralysis. ALS is incurable and has a bleak prognosis, with median survival of 3-5 years after the initial symptomatology. In ALS, motor neurons gradually degenerate and die. Many features of mitochondrial dysfunction are manifested in neurodegenerative diseases, including ALS. Mitochondria have shown to be an early target in ALS pathophysiology and contribute to disease progression. Disruption of their axonal transport, excessive generation of reactive oxygen species, disruption of the mitochondrial structure, dynamics, mitophagy, energy production, calcium buffering and apoptotic triggering have all been directly involved in disease pathogenesis and extensively reported in ALS patients and animal model systems. Alterations in energy production by motor neurons, which severely limit their survival capacity, are tightly linked to the redox status and mitochondria. The present review focuses on this link. Placing oxidative stress as a main pathophysiological mechanism, the molecular interactions and metabolic flows involved are analyzed. This leads to discussing potential therapeutic approaches targeting mitochondrial biology to slow disease progression.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Metabolismo Energético , Mitocôndrias/metabolismo , Estresse Oxidativo , Animais , Humanos , Neurônios Motores/patologia , Oxirredução
20.
Physiol Meas ; 42(7)2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34186519

RESUMO

Objective. The temperature of the sole of the foot has been suggested as an alternative to the measurement of plantar pressure during running despite the scarce evidence about their relationship. The temperature of the footwear outsole could also be representative of plantar pressure distribution due to its less multifactorial dependence. The aim of the study was to determine if plantar pressure during a prolonged run could be related to plantar temperature, either of the sole of the foot or the footwear outsole.Approach. Thirty recreational runners (15 males and 15 females) performed a 30 min running test on a treadmill. Thermographic images of the sole of the foot and the footwear outsole were taken before and immediately after the test, and dynamic plantar pressure was measured at the end of the test. Pearson correlations and stepwise multiple linear regressions were performed.Main results.Plantar pressure percentage was related to a moderate correlation with plantar temperature percentage in forefoot and rearfoot (P < 0.05), showing a greater relationship with the footwear outsole than with the sole of the foot (r = 0.52-0.73 versusr = 0.40-0.61, respectively). Moreover, moderate correlations were also observed between footwear outsole and sole of the foot temperature variables, especially in rearfoot.Significance. Footwear outsole temperature may be better related to plantar pressure distribution than sole of the foot temperature, in the forefoot and rearfoot. The midfoot is the most sensitive and variable region to analyze, as it does not seem to have any relationship with plantar pressure.


Assuntos
Corrida , Sapatos , Fenômenos Biomecânicos , Feminino , , Humanos , Masculino , Temperatura , Termografia
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