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1.
Adv Exp Med Biol ; 1232: 193-199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893410

RESUMO

Measurement of oxyhemoglobin (O2Hb) changes in the cerebral cortex using near-infrared spectroscopy (NIRS) shows that its levels increase during moderate-intensity exercise and persists after exercise. However, the effects of exercise duration on O2Hb persistence in the premotor cortex (PMC) are unknown. We aimed to determine the effects of exercise duration on the persistence of O2Hb changes after moderate-intensity cycling as exercise. Healthy young volunteers were recruited to participate in this study. After a 3-min rest period, the exercise was initiated at a workload corresponding to 50% VO2peak. The exercise continued for 10 min and 20 min, followed by 15 min of rest. The O2Hb levels in the right (R-PMC) and left premotor cortices (L-PMC) were measured using an NIRS system. The O2Hb values during the 15-min post-exercise rest period in the R-PMC were 0.010 ± 0.011 mM·cm after the 10-min exercise and 0.035 ± 0.010 mM·cm after the 20-min exercise, without significant differences (p = 0.104). The O2Hb value in the L-PMC during post-exercise rest (0.055 ± 0.010 mM·cm) after the 20-min exercise was significantly higher than that after the 10-min exercise (0.023 ± 0.007 mM·cm; p = 0.014). Thus, the effects of exercise duration on O2Hb persistence have laterality in the PMC.


Assuntos
Exercício , Córtex Motor , Consumo de Oxigênio , Oxiemoglobinas , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Feminino , Humanos , Masculino , Córtex Motor/metabolismo , Oxiemoglobinas/metabolismo , Fatores de Tempo , Adulto Jovem
2.
Adv Exp Med Biol ; 1232: 231-237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893415

RESUMO

Near-infrared spectroscopy (NIRS) during cardiopulmonary exercise test (CPX) has shown a correlation between prefrontal cortex (PFC) oxygenated hemoglobin (O2Hb) level and negative affective responses. We hypothesized that O2Hb changes differ between the PFC and motor-related areas. This study investigated changes in hemoglobin levels in the PFC and motor-related areas during CPX. Twelve young healthy adults participated in this study. They performed a CPX after 4 min of rest and 4 min of warming up. Cortical O2Hb, deoxygenated hemoglobin (HHb), and total hemoglobin (THb) levels were measured with NIRS during CPX. Regions of interest (ROI) were the PFC, premotor area (PMA), supplementary motor area (SMA), and primary motor cortex (M1). The anaerobic threshold (AT), respiratory compensation (RC), and peak oxygen uptake (Peak) points were determined. The rest, AT, RC and Peak points of O2Hb, HHb, and THb were averaged over 5 s; hemoglobin slopes, from RC to the Peak points, were calculated to compare functional changes in cortical oxygenation. Average values of O2Hb, HHb, and THb in each ROI were compared among the rest, AT, RC, and Peak points. Average values of hemoglobin slopes, from RC to Peak points, were compared among ROIs using Bonferroni multiple comparisons. The HHb of all ROIs significantly increased at Peak point, compared with at the AT point. THb of the PFC, PMA, and SMA significantly increased at the RC or Peak points, compared with at the rest point. Hemoglobin slopes, from RC to Peak, showed no significant differences among ROIs. Each ROI exhibited similar changes, regardless of cortical function.


Assuntos
Córtex Motor , Oxigênio , Córtex Pré-Frontal , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Teste de Esforço , Feminino , Humanos , Masculino , Córtex Motor/metabolismo , Oxigênio/metabolismo , Consumo de Oxigênio , Oxiemoglobinas/metabolismo , Córtex Pré-Frontal/metabolismo , Adulto Jovem
3.
Adv Exp Med Biol ; 1232: 239-244, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893416

RESUMO

Near-infrared time-resolved spectroscopy (NIRTRS) can quantitatively evaluate mean optical path length (MPL). Since an increase in optical absorbers in the NIR region (e.g. an increase in deoxygenated hemoglobin during exercise) would shorten the MPL, the NIRS measurement area may vary depending on physical and physiological characteristics of the measurement region and/or the exercise intensity. The aim of this study was to examine the changes in MPL measured by NIRTRS during ramp cycling exercise between fat layer thickness-matched subjects with different aerobic capacities. Healthy control (CON, n = 8) and endurance-trained males (TR, n = 8) performed ramp cycling exercise until exhaustion. Deoxygenated hemoglobin concentration (Deoxy-Hb), total hemoglobin concentration (Total-Hb) and oxygenated hemoglobin concentration (Oxy-Hb) were evaluated by a three-wavelength NIRTRS system. MPL in each wavelength (MPL760, MPL800 and MPL830) was monitored continuously. With increasing exercise intensity, Total- and Deoxy-Hb significantly increased and Oxy-Hb decreased in both groups. Total- and Oxy-Hb during exercise were significantly higher in TR than CON (P < 0.05, P < 0.01, respectively). Furthermore, Deoxy-Hb also tended to be higher in TR than CON (P = 0.07). In addition, MPL at all wavelengths significantly shortened with an increase in exercise intensity, with no differences between CON and TR. In particular, MPL760 at peak exercise shortened more than 10% compared to the start of exercise in both groups, even though MPL830 decreased only a few per cent. These findings suggest that the NIRS measurement area may be reduced during ramp cycling exercise due to shortened MPL. Additionally, the changes in MPL may be especially greater at 760 nm than at the other wavelengths due to greater changes in Deoxy-Hb during exercise. Furthermore, this study indicates that the measurements of muscle deoxygenation using continuous-wave NIRS can be less accurate since they are significantly affected by changes in the optical path length.


Assuntos
Exercício , Consumo de Oxigênio , Músculo Quadríceps , Adolescente , Adulto , Estudos de Casos e Controles , Teste de Esforço , Humanos , Masculino , Oxigênio/metabolismo , Oxiemoglobinas/metabolismo , Músculo Quadríceps/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
4.
Adv Exp Med Biol ; 1232: 245-251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893417

RESUMO

Skeletal muscle metabolic function is known to respond positively to endurance exercise interventions, such as marathon training. Studies investigating skeletal muscle have typically used muscle biopsy samples or magnetic resonance spectroscopy (MRS) to interrogate metabolic function. We aimed to non-invasively detect exercise-training-induced improvements in muscle function using broadband near-infrared spectroscopy (NIRS). We used NIRS to determine concentration changes in oxygenated haemoglobin (HbO2) and the oxidation state of cytochrome-c-oxidase (oxCCO) in gastrocnemius during arterial occlusion in 14 volunteers. We also used a cardio-pulmonary exercise test (CPET) to assess peak total body oxygen uptake (peakVO2; a measure of fitness). Measurements were made at baseline (BL) which was prior to a period of at least 16 weeks of training for the 2017 London Marathon, and then within 3 weeks after completion of the marathon, follow-up (FU). We observed an increase in locally measured muscle oxygen consumption and rate of oxCCO concentration change, but not in cardio-respiratory fitness measured as whole-body peak oxygen consumption (peakVO2).


Assuntos
Músculo Esquelético , Consumo de Oxigênio , Corrida , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Oxiemoglobinas/metabolismo
5.
Adv Exp Med Biol ; 1232: 331-337, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893428

RESUMO

Obesity, a risk factor of coronary artery disease, is known to cause peripheral microcirculatory disturbances. This study evaluated the relationship between the degree of obesity and peripheral microcirculatory disturbances, using peripheral near infrared spectroscopy (NIRS) with a vascular occlusion test (VOT). We compared correlations between the NIRS parameter changes induced by VOT and body mass index (BMI) in patients with and without statin therapy. A NIRS probe was set on the right thenar eminence, brachial artery blood flow was blocked for 3 min, and then released. Although total hemoglobin (ΔcHb), deoxyhemoglobin (ΔHHb) and tissue oxygenation index (ΔTOI) were not correlated with BMI, a significant negative correlation was found between oxyhemoglobin (ΔO2Hb) and BMI in the overall study population (r = -0.255, p-value 0.02). In addition, a significant negative correlation was found between ΔO2Hb and BMI in patients without statin therapy (r = -0.353, p-value 0.02) but not in patients with statin therapy (r = -0.181, p-value 0.27). These findings suggest that ΔO2Hb may be a useful indicator to assess peripheral microcirculation.


Assuntos
Índice de Massa Corporal , Doença da Artéria Coronariana , Espectroscopia de Luz Próxima ao Infravermelho , Idoso , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Microcirculação/fisiologia , Oxigênio , Consumo de Oxigênio , Oxiemoglobinas/metabolismo , Fatores de Risco , Espectroscopia de Luz Próxima ao Infravermelho/normas
6.
Adv Exp Med Biol ; 1232: 355-360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893431

RESUMO

Epicardial adipose tissue (EAT) is associated with visceral fat and various cardiac disorders, such as atrial fibrillation and adverse cardiovascular events. Therefore, it is important to develop a simple and non-invasive inspection method to assess EAT, to prevent unfavorable cardiac events. This study assessed correlations between near-infrared spectroscopy (NIRS) changes induced by a vascular occlusion test (VOT) and EAT volume measured by cardiac computed tomography (CCT) in patients with suspected coronary artery disease. We also assessed correlations between body mass index (BMI) and EAT volume in the same population. In addition, these correlations were compared in patients treated with statin therapy and in those without statin therapy. A NIRS probe was set on the right thenar eminence, and brachial artery blood flow was blocked for 3 min before being released. A negative correlation was found between oxyhemoglobin (ΔO2Hb) and EAT volume in the overall study population (r = -0.236, p = 0.03). Interestingly, although a strong correlation was observed in patients without statin therapy (r = -0.488, p < 0.001), this correlation was not observed in patients with statin therapy (r = 0.157, p = 0.34). These findings suggest that NIRS measurements with VOT may be a useful method to identify patients with high EAT volume and high cardiovascular risks.


Assuntos
Doença da Artéria Coronariana , Espectroscopia de Luz Próxima ao Infravermelho , Tecido Adiposo/metabolismo , Idoso , Índice de Massa Corporal , Angiografia por Tomografia Computadorizada , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Oxiemoglobinas/metabolismo , Fatores de Risco
7.
Br J Anaesth ; 124(1): 110-120, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31767144

RESUMO

BACKGROUND: We aimed to examine whether using a high fraction of inspired oxygen (FIO2) in the context of an individualised intra- and postoperative open-lung ventilation approach could decrease surgical site infection (SSI) in patients scheduled for abdominal surgery. METHODS: We performed a multicentre, randomised controlled clinical trial in a network of 21 university hospitals from June 6, 2017 to July 19, 2018. Patients undergoing abdominal surgery were randomly assigned to receive a high (0.80) or conventional (0.3) FIO2 during the intraoperative period and during the first 3 postoperative hours. All patients were mechanically ventilated with an open-lung strategy, which included recruitment manoeuvres and individualised positive end-expiratory pressure for the best respiratory-system compliance, and individualised continuous postoperative airway pressure for adequate peripheral oxyhaemoglobin saturation. The primary outcome was the prevalence of SSI within the first 7 postoperative days. The secondary outcomes were composites of systemic complications, length of intensive care and hospital stay, and 6-month mortality. RESULTS: We enrolled 740 subjects: 371 in the high FIO2 group and 369 in the low FIO2 group. Data from 717 subjects were available for final analysis. The rate of SSI during the first postoperative week did not differ between high (8.9%) and low (9.4%) FIO2 groups (relative risk [RR]: 0.94; 95% confidence interval [CI]: 0.59-1.50; P=0.90]). Secondary outcomes, such as atelectasis (7.7% vs 9.8%; RR: 0.77; 95% CI: 0.48-1.25; P=0.38) and myocardial ischaemia (0.6% [n=2] vs 0% [n=0]; P=0.47) did not differ between groups. CONCLUSIONS: An oxygenation strategy using high FIO2 compared with conventional FIO2 did not reduce postoperative SSIs in abdominal surgery. No differences in secondary outcomes or adverse events were found. CLINICAL TRIAL REGISTRATION: NCT02776046.


Assuntos
Oxigênio/uso terapêutico , Respiração Artificial/métodos , Infecção da Ferida Cirúrgica/prevenção & controle , Abdome/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Oxiemoglobinas/análise , Oxiemoglobinas/metabolismo , Assistência Perioperatória , Respiração com Pressão Positiva , Medicina de Precisão , Atelectasia Pulmonar/epidemiologia , Atelectasia Pulmonar/etiologia , Resultado do Tratamento
8.
Wien Klin Wochenschr ; 131(15-16): 381-384, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267164

RESUMO

Healthy human blood contains only a trace amount of methemoglobin (Hb M), less than 1%. In Hb M iron is present in the oxidized ferric state (Fe3+) not in the reduced ferrous form (Fe2+) and this reduces the ability of hemoglobin to bind oxygen. The described rare hemoglobin variant Hb M­Hyde Park (also known as Hb M-Akita) results from the substitution of amino acid tyrosine by histidine at position 93 of the beta-globin chain of hemoglobin. The rare Hb variant Hb M­Hyde Park (Hb M­Akita) is mainly inherited autosomal dominant and causes methemoglobinemia. Due to the low frequency of inherited Hb M variants, the diagnosis is challenging. Here, we here report on a family with Hb M­Hyde Park (Hb M­Akita) whose members demonstrated Hb M > 10%, but were, asymptomatic except for chronic cyanosis. Due to human mobility and migration other hemogobin variants, such as beta-thalassemia minor have spread to Austria . A genetic combination of two different hemoglobin variants may result in severe anemia. Genetic counseling for patients with hemoglobin variants, including Hb M­Hyde Park (Hb M­Akita) and beta-thalassemia minor, is essential.


Assuntos
Hemoglobina M/genética , Metemoglobinemia , Áustria , Hemoglobinas Anormais/genética , Hemoglobinas Anormais/metabolismo , Humanos , Metemoglobinemia/sangue , Metemoglobinemia/diagnóstico , Metemoglobinemia/genética , Oxiemoglobinas/metabolismo , Talassemia beta/genética
9.
Eur J Appl Physiol ; 119(8): 1819-1828, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187281

RESUMO

PURPOSE: The aim was to compare changes in peripheral and cerebral oxygenation, as well as metabolic and performance responses during conditions of blood flow restriction (BFR, bilateral vascular occlusion at 0% vs. 45% of resting pulse elimination pressure) and systemic hypoxia (~ 400 m, FIO2 20.9% vs. ~ 3800 m normobaric hypoxia, FIO2 13.1 ± 0.1%) during repeated sprint tests to exhaustion (RST) between leg- and arm-cycling exercises. METHODS: Seven participants (26.6 ± 2.9 years old; 74.0 ± 13.1 kg; 1.76 ± 0.09 m) performed four sessions of RST (10-s maximal sprints with 20-s recovery until exhaustion) during both leg and arm cycling to measure power output and metabolic equivalents as well as oxygenation (near-infrared spectroscopy) of the muscle tissue and prefrontal cortex. RESULTS: Mean power output was lower in arms than legs (316 ± 118 vs. 543 ± 127 W; p < 0.001) and there were no differences between conditions for a given limb. Arms demonstrated greater changes in concentration of deoxyhemoglobin (∆[HHb], - 9.1 ± 6.1 vs. - 6.5 ± 5.6 µm) and total hemoglobin concentration (∆[tHb], 15.0 ± 10.8 vs. 11.9 ± 7.9 µm), as well as the absolute maximum tissue saturation index (TSI, 62.0 ± 8.3 vs. 59.3 ± 8.1%) than legs, respectively (p < 0.001), demonstrating a greater capacity for oxygen extraction. Further, there were greater changes in tissue blood volume [tHb] during BFR only compared to all other conditions (p < 0.01 for all). CONCLUSIONS: The combination of BFR and/or hypoxia led to increased changes in [HHb] and [tHb] likely due to greater vascular resistance, to which arms were more responsive than legs.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Hipóxia/fisiopatologia , Músculo Esquelético/irrigação sanguínea , Consumo de Oxigênio , Córtex Pré-Frontal/irrigação sanguínea , Reperfusão/efeitos adversos , Adulto , Feminino , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Masculino , Músculo Esquelético/fisiologia , Oxiemoglobinas/metabolismo
10.
Sensors (Basel) ; 19(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31071987

RESUMO

An optical probe was developed to measure the change of oxy-hemoglobin (OHb), deoxy- hemoglobin (RHb), and total hemoglobin (THb) along with temperature from the vaginal wall of female rats. Apomorphine (APO, 80 µg/kg) was administered to elicit sexual arousal in female Sprague Dawley rats (SD, 180-200 g). The behavior changes caused by APO administration were checked before monitoring vaginal responses. The changes of oxy-, deoxy-, and total hemoglobin concentration and the temperature from the vaginal wall were monitored before, during, and after APO administration. Animals were under anesthesia during the measurement. After APO administration, the concentration of OHb (55 ± 29 µM/DPF), RHb (33 ± 25 µM/DPF), and THb (83 ± 59 µM/DPF) in the vaginal wall increased in a few min, while saline administration did not cause any significant change. In case of the vaginal temperature change, APO decreased the temperature slightly in the vaginal wall while saline administration did not show any temperature change in the vaginal wall. As the outcomes demonstrated, the developed probe can detect hemodynamic and temperature variation in the vaginal wall. The hemodynamic information acquired by the probe can be utilized to establish an objective and accurate standard of female sexual disorders.


Assuntos
Hemodinâmica/fisiologia , Monitorização Fisiológica , Óptica e Fotônica/instrumentação , Comportamento Sexual Animal/fisiologia , Vagina/fisiologia , Animais , Apomorfina/farmacologia , Desenho de Equipamento , Feminino , Oxiemoglobinas/metabolismo , Ratos Sprague-Dawley , Respiração
11.
PLoS Genet ; 15(4): e1007739, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30990817

RESUMO

Sleep disordered breathing (SDB)-related overnight hypoxemia is associated with cardiometabolic disease and other comorbidities. Understanding the genetic bases for variations in nocturnal hypoxemia may help understand mechanisms influencing oxygenation and SDB-related mortality. We conducted genome-wide association tests across 10 cohorts and 4 populations to identify genetic variants associated with three correlated measures of overnight oxyhemoglobin saturation: average and minimum oxyhemoglobin saturation during sleep and the percent of sleep with oxyhemoglobin saturation under 90%. The discovery sample consisted of 8,326 individuals. Variants with p < 1 × 10(-6) were analyzed in a replication group of 14,410 individuals. We identified 3 significantly associated regions, including 2 regions in multi-ethnic analyses (2q12, 10q22). SNPs in the 2q12 region associated with minimum SpO2 (rs78136548 p = 2.70 × 10(-10)). SNPs at 10q22 were associated with all three traits including average SpO2 (rs72805692 p = 4.58 × 10(-8)). SNPs in both regions were associated in over 20,000 individuals and are supported by prior associations or functional evidence. Four additional significant regions were detected in secondary sex-stratified and combined discovery and replication analyses, including a region overlapping Reelin, a known marker of respiratory complex neurons.These are the first genome-wide significant findings reported for oxyhemoglobin saturation during sleep, a phenotype of high clinical interest. Our replicated associations with HK1 and IL18R1 suggest that variants in inflammatory pathways, such as the biologically-plausible NLRP3 inflammasome, may contribute to nocturnal hypoxemia.


Assuntos
Hexoquinase/genética , Subunidade alfa de Receptor de Interleucina-18/genética , Oxiemoglobinas/metabolismo , Sono/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Moléculas de Adesão Celular Neuronais/genética , Biologia Computacional , Proteínas da Matriz Extracelular/genética , Feminino , Redes Reguladoras de Genes , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Hipóxia/sangue , Hipóxia/genética , Masculino , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas do Tecido Nervoso/genética , Oxigênio/sangue , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Serina Endopeptidases/genética , Síndromes da Apneia do Sono/sangue , Síndromes da Apneia do Sono/genética , Adulto Jovem
12.
Jpn J Radiol ; 37(6): 437-448, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30891667

RESUMO

PURPOSE: To determine whether functional near-infrared spectroscopy (fNIRS) allows monitoring fatigue in radiologists during prolonged image interpretation. MATERIALS AND METHODS: Nine radiologists participated as subjects in the present study and continuously interpreted medical images and generated reports for cases for more than 4 h under real clinical work conditions. We measured changes in oxygenated hemoglobin concentrations [oxy-Hb] in the prefrontal cortex using 16-channel fNIRS (OEG16ME, Spectratech) every hour during the Stroop task to evaluate fatigue of radiologists and recorded fatigue scale (FS) as a behavior data. RESULTS: Two subjects showed a subjective feeling of fatigue and an apparent decrease in brain activity after 4 h, so the experiment was completed in 4 h. The remaining seven subjects continued the experiment up to 5 h. FS decreased with time, and a significant reduction was observed between before and the end of image interpretation. Seven out of nine subjects showed a minimum [oxy-Hb] change at the end of prolonged image interpretation. The mean change of [oxy-Hb] at the end of all nine subjects was significantly less than the maximum during image interpretation. CONCLUSION: fNIRS using the change of [oxy-Hb] may be useful for monitoring fatigue in radiologists during image interpretation.


Assuntos
Fadiga/diagnóstico , Fadiga/metabolismo , Oxiemoglobinas/metabolismo , Córtex Pré-Frontal/metabolismo , Radiologistas/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/estatística & dados numéricos , Masculino , Espectroscopia de Luz Próxima ao Infravermelho , Teste de Stroop , Tempo , Carga de Trabalho/psicologia , Adulto Jovem
13.
BMC Neurosci ; 20(1): 12, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885121

RESUMO

BACKGROUND: Transcranial focused ultrasound (tFUS) attracts wide attention in neuroscience as an effective noninvasive approach to modulate brain circuits. In spite of this, the effects of tFUS on the brain is still unclear, and further investigation is needed. The present study proposes to use near-infrared spectroscopy (NIRS) to observe cerebral hemodynamic change caused by tFUS in a noninvasive manner. RESULTS: The results show a transient increase of oxyhemoglobin and decrease of deoxyhemoglobin concentration in the mouse model induced by ultrasound stimulation of the somatosensory cortex with a frequency of 8 MHz but not in sham. In addition, the amplitude of hemodynamics change can be related to the peak intensity of the acoustic wave. CONCLUSION: High frequency 8 MHz ultrasound was shown to induce hemodynamic changes measured using NIRS through the intact mouse head. The implementation of NIRS offers the possibility of investigating brain response noninvasively for different tFUS parameters through cerebral hemodynamic change.


Assuntos
Hemodinâmica/fisiologia , Córtex Somatossensorial/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Terapia por Ultrassom , Animais , Feminino , Hemoglobinas/metabolismo , Camundongos Endogâmicos BALB C , Oxiemoglobinas/metabolismo , Dados Preliminares , Distribuição Aleatória , Processamento de Sinais Assistido por Computador , Córtex Somatossensorial/irrigação sanguínea , Terapia por Ultrassom/métodos , Ondas Ultrassônicas
14.
Int J Sports Med ; 40(6): 376-384, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30900226

RESUMO

Ten highly-trained Jiu-Jitsu fighters performed 2 repeated-sprint sessions, each including 2 sets of 8 x ~6 s back-and-forth running sprints on a tatami. One session was carried out with normal breathing (RSN) and the other with voluntary hypoventilation at low lung volume (RSH-VHL). Prefrontal and vastus lateralis muscle oxyhemoglobin ([O2Hb]) and deoxyhemoglobin ([HHb]) were monitored by near-infrared spectroscopy. Arterial oxygen saturation (SpO2), heart rate (HR), gas exchange and maximal blood lactate concentration ([La]max) were also assessed. SpO2 was significantly lower in RSH-VHL than in RSN whereas there was no difference in HR. Muscle oxygenation was not different between conditions during the entire exercise. On the other hand, in RSH-VHL, cerebral oxygenation was significantly lower than in RSN (-6.1±5.4 vs-1.5±6.6 µm). Oxygen uptake was also higher during the recovery periods whereas [La]max tended to be lower in RSH-VHL. The time of the sprints was not different between conditions. This study shows that repeated shuttle-run sprints with VHL has a limited impact on muscle deoxygenation but induces a greater fall in cerebral oxygenation compared with normal breathing conditions. Despite this phenomenon, performance is not impaired, probably because of a higher oxygen uptake during the recovery periods following sprints.


Assuntos
Desempenho Atlético/fisiologia , Encéfalo/metabolismo , Músculo Esquelético/metabolismo , Respiração , Corrida/fisiologia , Frequência Cardíaca , Hemoglobinas/metabolismo , Humanos , Hipoventilação , Ácido Láctico/sangue , Oxigênio/sangue , Consumo de Oxigênio/fisiologia , Oxiemoglobinas/metabolismo , Percepção , Esforço Físico , Troca Gasosa Pulmonar , Espectroscopia de Luz Próxima ao Infravermelho
15.
Neurosci Lett ; 699: 172-176, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30753910

RESUMO

Assessing the result of conceptual change (i.e., whether an individual has come to correctly understand a science concept) is important in science education, however traditional assessment methods lack objectivity. In this study, permutation entropy (PE) based complexity, a kind of entropy used to quantify the complexity describing the uncertainty of time series, was explored by the functional near-infrared spectroscopy to seek an objective neurobiological indicator for this assessment. Two groups of participants, engineering students (classified as "experts") and humanities students (classified as "novices"), were tested on their conceptions to discriminate the speed of cars according to the animation, while the hemodynamic response was recorded over their inferior frontal gyrus (IFG). The activation analysis, PE based complexity analysis, and k-means clustering analysis were conducted. The results indicated that experts performed the task better than novices in behavioral performances, and PE values in the IFG were smaller for experts, especially in the right IFG. Furthermore, the k-means clustering analysis showed that the PE could be a feature to classify the students into two groups. It is concluded that the PE is a promising neurobiological indicator for assessment of this kind.


Assuntos
Encéfalo/fisiologia , Córtex Pré-Frontal/fisiologia , Resolução de Problemas/fisiologia , Competência Profissional , Entropia , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Incerteza , Adulto Jovem
16.
Biochemistry ; 58(10): 1400-1410, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30789715

RESUMO

Oxyhemoglobin (HbO2) coexisting with equimolar NADH retards autoxidation and oxidant-induced metHb formation based on the pseudocatalase (CAT) and pseudosuperoxide dismutase (SOD) activities. In this work, we compared the effects of NADH with those of NADPH and estimated the binding site of NAD(P)H to HbO2 to elucidate the antioxidative mechanisms. The results clarified that pseudo-CAT and pseudo-SOD activities of HbO2 coexisting with NADPH were similar to activities obtained with NADH. Prompt MetHb formation (<40 min) facilitated by oxidants (H2O2, NO, and NaNO2) was hindered by NADPH. These effects were similar to those of NADH. However, we found that NADPH is thermally unstable compared to NADH and that NADPH cannot sustain antioxidative effects for a long period of autoxidation to metHb such as 24 h. Lineweaver-Burk plots clarified that the Michaelis constants of these pseudoenzymatic activities are in the millimolar range. Addition of inositol hexaphosphate (IHP) and 2,3-diphosphoglycerate (DPG), which are known to bind not only with deoxyHb but also weakly with HbO2, showed competitive inhibition of pseudoenzymatic activities. These results suggest that the binding site of NADH and NADPH on HbO2 is the same as those of IHP and DPG. 31P nuclear magnetic resonance definitively showed 1:1 stoichiometric binding of NADH to HbO2. High-performance liquid chromatography analysis showed that NADH preferentially inhibited autoxidation of α-subunit heme. Docking simulations also predicted that the binding site of relaxed-state HbO2 with NAD(P)H is the same as those with IHP and DPG. Collectively, the pseudoenzymatic activities of HbO2 coexisting with NAD(P)H are induced by the 1:1 stoichiometric binding of NAD(P)H to HbO2.


Assuntos
Metemoglobina/biossíntese , NADP/metabolismo , Oxiemoglobinas/metabolismo , Antioxidantes/metabolismo , Sítios de Ligação/genética , Catalase/metabolismo , Hemoglobinas , Peróxido de Hidrogênio , Metemoglobina/metabolismo , NAD/metabolismo , Oxidantes , Oxirredução , Superóxido Dismutase/metabolismo
17.
Respir Res ; 20(1): 6, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621691

RESUMO

INTRODUCTION: Little is known on the pulmonary gradients of oxyhemoglobin, carboxyhemoglobin and methemoglobin in pulmonary arterial hypertension (PAH). We sought to determine these gradients in group 1 PAH and assess their association with disease severity and survival. METHODS: During right heart catheterization (RHC) we obtained blood from pulmonary artery (PA) and pulmonary artery wedge (PAW) positions and used co-oximetry to test their gasometric differences. RESULTS: We included a total of 130 patients, 65 had group 1 PAH, 40 had pulmonary hypertension (PH) from groups 2-5 and 25 had no PH during RHC. In all groups, PAW blood had higher pH, carboxyhemoglobin and lactate as well as lower pCO2 than PA blood. In group 1 PAH (age 58 ± 15 years, 72% females), methemoglobin in the PAW was lower than in the PA blood (0.83% ± 0.43 vs 0.95% ± 0.50, p = 0.03) and was directly associated with the degree of change in pulmonary vascular resistance (R = 0.35, p = 0.02) during inhaled nitric oxide test. Oxyhemoglobin in PA (HR (95%CI): 0.90 (0.82-0.99), p = 0.04) and PAW (HR (95%CI): 0.91 (0.84-0.98), p = 0.003) blood was associated with adjusted survival in PAH. CONCLUSIONS: Marked differences were observed in the gasometric determinations between PAW and PA blood. The pulmonary gradient of methemoglobin was lower in PAH patients compared to controls and a higher PAW blood methemoglobin was associated with a more pronounced pulmonary vascular response to inhaled nitric oxide. Pulmonary artery and PAW oxyhemoglobin tracked with disease severity and survival in PAH.


Assuntos
Hipertensão Pulmonar/sangue , Artéria Pulmonar/metabolismo , Pressão Propulsora Pulmonar/fisiologia , Resistência Vascular/fisiologia , Adulto , Idoso , Gasometria/métodos , Cateterismo Cardíaco/tendências , Estudos Transversais , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/cirurgia , Masculino , Pessoa de Meia-Idade , Oxiemoglobinas/metabolismo , Artéria Pulmonar/cirurgia , Estudos Retrospectivos
18.
Int Rev Immunol ; 38(1): 3-17, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30633597

RESUMO

Infection proliferates and disseminates rapidly and so innate immunity should react effectively and fast. Innate immunity mechanisms depend upon fluid dynamics and are different in compartments with slow (the tissues) and rapid (the bloodstream) liquid flow. In the tissues, coagulation initiated by clotting factors, platelets and erythrocytes, is prompt and effective mechanism of the first line of antibacterial defense. Resident macrophages, transmigrated neutrophils, monocytes, NETs and platelets are the second line of the defense. In the bloodstream the first line of innate immunity defense are erythrocytes that kill pathogens by oxygen, released from oxyhemoglobin (oxycytosis); the second line of the defense is coagulation that in case of overactivation may cause disseminated intravascular coagulation (DIC). Blood coagulation is the fastest mechanism of infection confinement and inactivation. It is the first and the last line of innate immunity defense and occurs both in the tissues and the bloodstream.


Assuntos
Coagulação Sanguínea , Plaquetas/fisiologia , Eritrócitos/fisiologia , Macrófagos/fisiologia , Neutrófilos/fisiologia , Antibacterianos , Humanos , Imunidade Inata , Oxiemoglobinas/metabolismo
19.
Am J Clin Nutr ; 109(2): 353-360, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30624594

RESUMO

Background: Age-related declines in cognitive function and cerebral perfusion increase the risk of dementia. Although nutrition and exercise may be effective in reducing cognitive decline, the effect of lactotripeptide (LTP) on cerebral oxygenation and hemodynamics remains unclear. Objectives: The aim of this study was to investigate the effects of LTP ingestion on cerebral oxygenation, cognitive function, and vascular function in middle-aged and older adults with or without an exercise intervention. Methods: We recruited 2 separate groups of participants, one with and one without an exercise intervention. Each group was then randomly assigned into a placebo group and an LTP group. The participants ingested a placebo or LTP every day. The exercise group performed aerobic exercises 4-6 d/wk. Before and after the 8-wk intervention, we measured oxygenated hemoglobin (oxy-Hb) concentration (oxy-Hb change) in the prefrontal cortex during the Stroop task (primary outcome), Stroop interference time, and carotid artery ß-stiffness (both secondary outcomes). Results: Sixty-four participants completed the study. Changes in oxy-Hb signal in the prefrontal cortex were greater in the LTP group than in the placebo group under both the exercise and nonexercise conditions (P < 0.05). In addition, the magnitude of improvement in the oxy-Hb change in the left prefrontal cortex was correlated with Stroop interference (r = -0.39, P < 0.05) and carotid ß-stiffness (r = -0.41, P < 0.05). Conclusions: An 8-wk intake of LTP increased cerebral oxygenation in the prefrontal cortex region in middle-aged and older adults, with and without exercise. The intervention-induced improvements in brain neural activation were associated with cognitive and vascular function. This trial was registered at www.umin.ac.jp as UMIN000022313.


Assuntos
Cognição , Disfunção Cognitiva/metabolismo , Função Executiva , Exercício/psicologia , Oligopeptídeos/farmacologia , Oxiemoglobinas/metabolismo , Córtex Pré-Frontal/metabolismo , Idoso , Animais , Artérias Carótidas/patologia , Cognição/efeitos dos fármacos , Disfunção Cognitiva/patologia , Disfunção Cognitiva/terapia , Função Executiva/efeitos dos fármacos , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Leite/química , Córtex Pré-Frontal/efeitos dos fármacos , Fenômenos Fisiológicos Respiratórios , Teste de Stroop , Rigidez Vascular
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