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1.
Braz J Med Biol Res ; 52(8): e8688, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31389493

RESUMEN

The objective of this study was to investigate the effect of whole body vibration (WBV) exercise on oxidative stress markers in a group of women with fibromyalgia (FM) compared to a group of healthy women (CT). Twenty-one women diagnosed with FM and 21 age- and weight-matched healthy women were enrolled the study. Plasma oxidative stress markers (primary outcomes) were evaluated at rest and after WBV, and included thiobarbituric acid reactive substances (TBARS), iron reduction capacity (FRAP), superoxide dismutase antioxidant enzymes activity (SOD), and catalase (CAT). At rest, the FM group had higher TBARS (P<0.001) and FRAP (P<0.001), and lower CAT (P=0.005) compared to the CT. In the CT group, the WBV had no effect on TBARS (P=0.559) and FRAP (P=0.926), whereas it increased both SOD (P<0.001) and CAT (P<0.001). In the FM group, the WBV reduced TBARS (p <0.001), FRAP (P<0.001), and CAT (P=0.005), while it increased SOD (P=0.019). There was an interaction effect (moments vs groups) in the TBARS (effect size=1.34), FRAP (effect size=0.93), CAT (effect size=1.45), and SOD (effect size=1.44) (P<0.001). A single trial of WBV exercise improved all oxidant and antioxidant parameters towards a greater adaptation to the stress response in FM women.


Asunto(s)
Biomarcadores/sangre , Fibromialgia/sangre , Estrés Oxidativo/fisiología , Vibración , Estudios de Casos y Controles , Femenino , Fibromialgia/fisiopatología , Humanos , Persona de Mediana Edad
2.
Braz. j. med. biol. res ; 52(8): e8688, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011611

RESUMEN

The objective of this study was to investigate the effect of whole body vibration (WBV) exercise on oxidative stress markers in a group of women with fibromyalgia (FM) compared to a group of healthy women (CT). Twenty-one women diagnosed with FM and 21 age- and weight-matched healthy women were enrolled the study. Plasma oxidative stress markers (primary outcomes) were evaluated at rest and after WBV, and included thiobarbituric acid reactive substances (TBARS), iron reduction capacity (FRAP), superoxide dismutase antioxidant enzymes activity (SOD), and catalase (CAT). At rest, the FM group had higher TBARS (P<0.001) and FRAP (P<0.001), and lower CAT (P=0.005) compared to the CT. In the CT group, the WBV had no effect on TBARS (P=0.559) and FRAP (P=0.926), whereas it increased both SOD (P<0.001) and CAT (P<0.001). In the FM group, the WBV reduced TBARS (p <0.001), FRAP (P<0.001), and CAT (P=0.005), while it increased SOD (P=0.019). There was an interaction effect (moments vs groups) in the TBARS (effect size=1.34), FRAP (effect size=0.93), CAT (effect size=1.45), and SOD (effect size=1.44) (P<0.001). A single trial of WBV exercise improved all oxidant and antioxidant parameters towards a greater adaptation to the stress response in FM women.


Asunto(s)
Humanos , Vibración , Biomarcadores/sangre , Fibromialgia/sangre , Estrés Oxidativo/fisiología , Fibromialgia/fisiopatología , Estudios de Casos y Controles
3.
Braz J Med Biol Res ; 51(4): e6775, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29513791

RESUMEN

The aims of this study were 1) to characterize the intensity of the vibration stimulation in women diagnosed with fibromyalgia (FM) compared to a control group of healthy women (HW) matched by age and anthropometric parameters, and 2) to investigate the effect of a single session of whole body vibration (WBV) on inflammatory responses. Levels of adipokines, soluble tumor necrosis factor receptors (sTNFr1, sTNFr2), and brain-derived neurotrophic factor (BDNF) were determined by enzyme-linked immunosorbent assay. Oxygen consumption (VO2) was estimated by a portable gas analysis system, heart rate (HR) was measured using a HR monitor, and perceived exertion (RPE) was evaluated using the Borg scale of perceived exertion. Acutely mild WBV increased VO2 and HR similarly in both groups. There was an interaction (disease vs vibration) in RPE (P=0.0078), showing a higher RPE in FM compared to HW at rest, which further increased in FM after acute WBV, whereas it remained unchanged in HW. In addition, there was an interaction (disease vs vibration) in plasma levels of adiponectin (P=0.0001), sTNFR1 (P=0.000001), sTNFR2 (P=0.0052), leptin (P=0.0007), resistin (P=0.0166), and BDNF (P=0.0179). In conclusion, a single acute session of mild and short WBV can improve the inflammatory status in patients with FM, reaching values close to those of matched HW at their basal status. The neuroendocrine mechanism seems to be an exercise-induced modulation towards greater adaptation to stress response in these patients.


Asunto(s)
Ejercicio Físico , Fibromialgia/sangre , Fibromialgia/terapia , Mediadores de Inflamación/sangre , Vibración , Adipoquinas/sangre , Biomarcadores/sangre , Factor Neurotrófico Derivado del Encéfalo/sangre , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Inflamación/sangre , Inflamación/terapia , Interleucina-8/sangre , Leptina/sangre , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Receptores del Factor de Necrosis Tumoral/sangre , Resistina/sangre
4.
Braz J Med Biol Res ; 49(11): e5181, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27828665

RESUMEN

Osteoarthritis of the knee (kOA) is a disease that mainly affects the elderly and can lead to major physical and functional limitations. However, the specific effects of walking, particularly on the immune system, are unknown. Therefore, this study aimed to analyze the effect of 12 weeks of walking (3×/week) on the leukocyte profile and quality of life (QL) of elderly women with kOA. Sixteen women (age: 67±4 years, body mass index: 28.07±4.16 kg/m2) participated in a walking program. The variables were assessed before and after 12 weeks of training with a progressively longer duration (30-55 min) and higher intensity (72-82% of HRmax determined using a graded incremental treadmill test). The QL was assessed using the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), and blood samples were collected for analysis with a cell counter and the San Fac flow cytometer. Walking training resulted in a 47% enhancement of the self-reported QL (P<0.05) and a 21% increase in the VO2max (P<0.0001) in elderly women with kOA. Furthermore, there was a reduction in CD4+ cells (pre=46.59±7%, post=44.58±9%, P=0.0189) and a higher fluorescence intensity for CD18+CD4+ (pre=45.30±10, post=64.27±33, P=0.0256) and CD18+CD8+ (pre=64.2±27, post=85.02±35, P=0.0130). In conclusion, the walking program stimulated leukocyte production, which may be related to the immunomodulatory effect of exercise. Walking also led to improvements in the QL and physical performance in elderly women with kOA.


Asunto(s)
Recuento de Células Sanguíneas , Terapia por Ejercicio/métodos , Activación de Linfocitos/fisiología , Osteoartritis de la Rodilla/rehabilitación , Calidad de Vida , Caminata/fisiología , Anciano , Evaluación de la Discapacidad , Femenino , Citometría de Flujo , Humanos , Osteoartritis de la Rodilla/sangre , Consumo de Oxígeno , Linfocitos T/citología , Factores de Tiempo
5.
Braz J Med Biol Res ; 49(11): e5512, 2016 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-27783809

RESUMEN

Chronic exposure to cigarette smoke seems to be related to an increase of pro-inflammatory cytokines, oxidative stress and changes in muscular and physical performances of healthy smokers. However, these parameters have not yet been evaluated simultaneously in previous studies. The participants of this study were healthy males divided into two groups: smokers (n=20) and non-smokers (n=20). Inflammation was evaluated by measuring plasma levels of the cytokines IL-10, IL-6 e TNF-α, and of the soluble receptors sTNFR1 and sTNFR2. Oxidative stress was evaluated by determination of thiobarbituric acid reactive substances (TBARS) plasma levels, total antioxidant capacity of plasma and erythrocytes activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase. Muscular performance was evaluated by measuring the peak torque of knee flexors and extensors, and by determining the total work of the knee extensors. Physical performance was assessed by measuring the peak oxygen uptake (VO2 peak), the maximum heart rate (HRmax) and the walking distance in the shuttle walking test. Smokers showed an increase in the levels of the sTNFR1 and TBARS and a decrease in the total antioxidant capacity of plasma, in the catalase activity and in the total work (P<0.05). IL-6, IL-10, sTNFR2, SOD, peak torque, VO2 peak, HRmax and walking distance were similar between groups. Smokers presented increased oxidative stress and skeletal muscle dysfunction, demonstrating that the changes in molecular and muscular parameters occur simultaneously in healthy smokers.


Asunto(s)
Músculo Esquelético/fisiopatología , Estrés Oxidativo/fisiología , Fumar/fisiopatología , Adulto , Estudios de Casos y Controles , Humanos , Inflamación/sangre , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Factor de Necrosis Tumoral alfa/sangre
6.
Braz. j. med. biol. res ; 49(3): e5026, Mar. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-771944

RESUMEN

Hypertension is characterized by a pro-inflammatory status, including redox imbalance and increased levels of pro-inflammatory cytokines, which may be exacerbated after heat exposure. However, the effects of heat exposure, specifically in individuals with inflammatory chronic diseases such as hypertension, are complex and not well understood. This study compared the effects of heat exposure on plasma cytokine levels and redox status parameters in 8 hypertensive (H) and 8 normotensive (N) subjects (age: 46.5±1.3 and 45.6±1.4 years old, body mass index: 25.8±0.8 and 25.6±0.6 kg/m2, mean arterial pressure: 98.0±2.8 and 86.0±2.3 mmHg, respectively). They remained at rest in a sitting position for 10 min in a thermoneutral environment (22°C) followed by 30 min in a heated environmental chamber (38°C and 60% relative humidity). Blood samples were collected before and after heat exposure. Plasma cytokine levels were measured using sandwich ELISA kits. Plasma redox status was determined by thiobarbituric acid reactive substances (TBARS) levels and ferric reducing ability of plasma (FRAP). Hypertensive subjects showed higher plasma levels of IL-10 at baseline (P<0.05), although levels of this cytokine were similar between groups after heat exposure. Moreover, after heat exposure, hypertensive individuals showed higher plasma levels of soluble TNF receptor (sTNFR1) and lower TBARS (P<0.01) and FRAP (P<0.05) levels. Controlled hypertensive subjects, who use angiotensin-converting-enzyme inhibitor (ACE inhibitors), present an anti-inflammatory status and balanced redox status. Nevertheless, exposure to a heat stress condition seems to cause an imbalance in the redox status and an unregulated inflammatory response.


Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Citocinas/sangre , Hipertensión/fisiopatología , Presión Arterial/fisiología , Presión Sanguínea/fisiología , Estudios de Casos y Controles , Frecuencia Cardíaca/fisiología , Calor , Hipertensión/sangre , Inflamación/fisiopatología , Peroxidación de Lípido/fisiología , Oxidación-Reducción , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
7.
Braz J Med Biol Res ; 49(3)2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26840715

RESUMEN

Hypertension is characterized by a pro-inflammatory status, including redox imbalance and increased levels of pro-inflammatory cytokines, which may be exacerbated after heat exposure. However, the effects of heat exposure, specifically in individuals with inflammatory chronic diseases such as hypertension, are complex and not well understood. This study compared the effects of heat exposure on plasma cytokine levels and redox status parameters in 8 hypertensive (H) and 8 normotensive (N) subjects (age: 46.5±1.3 and 45.6±1.4 years old, body mass index: 25.8±0.8 and 25.6±0.6 kg/m2, mean arterial pressure: 98.0±2.8 and 86.0±2.3 mmHg, respectively). They remained at rest in a sitting position for 10 min in a thermoneutral environment (22°C) followed by 30 min in a heated environmental chamber (38°C and 60% relative humidity). Blood samples were collected before and after heat exposure. Plasma cytokine levels were measured using sandwich ELISA kits. Plasma redox status was determined by thiobarbituric acid reactive substances (TBARS) levels and ferric reducing ability of plasma (FRAP). Hypertensive subjects showed higher plasma levels of IL-10 at baseline (P<0.05), although levels of this cytokine were similar between groups after heat exposure. Moreover, after heat exposure, hypertensive individuals showed higher plasma levels of soluble TNF receptor (sTNFR1) and lower TBARS (P<0.01) and FRAP (P<0.05) levels. Controlled hypertensive subjects, who use angiotensin-converting-enzyme inhibitor (ACE inhibitors), present an anti-inflammatory status and balanced redox status. Nevertheless, exposure to a heat stress condition seems to cause an imbalance in the redox status and an unregulated inflammatory response.


Asunto(s)
Citocinas/sangre , Calor , Hipertensión/fisiopatología , Adulto , Presión Arterial/fisiología , Presión Sanguínea/fisiología , Estudios de Casos y Controles , Frecuencia Cardíaca/fisiología , Humanos , Hipertensión/sangre , Inflamación/fisiopatología , Peroxidación de Lípido/fisiología , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
8.
Braz. j. med. biol. res ; 48(12): 1122-1129, Dec. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-762918

RESUMEN

Individuals with systemic arterial hypertension have a higher risk of heat-related complications. Thus, the aim of this study was to examine the thermoregulatory responses of hypertensive subjects during recovery from moderate-intensity exercise performed in the heat. A total of eight essential hypertensive (H) and eight normotensive (N) male subjects (age=46.5±1.3 and 45.6±1.4 years, body mass index=25.8±0.8 and 25.6±0.6 kg/m2, mean arterial pressure=98.0±2.8 and 86.0±2.3 mmHg, respectively) rested for 30 min, performed 1 h of treadmill exercise at 50% of maximal oxygen consumption, and rested for 1 h after exercise in an environmental chamber at 38°C and 60% relative humidity. Skin and core temperatures were measured to calculate heat exchange parameters. Mean arterial pressure was higher in the hypertensive than in the normotensive subjects throughout the experiment (P<0.05, unpaired t-test). The hypertensive subjects stored less heat (H=-24.23±3.99 W·m−2vs N=-13.63±2.24 W·m−2, P=0.03, unpaired t-test), experienced greater variations in body temperature (H=-0.62±0.05°C vsN=-0.35±0.12°C, P=0.03, unpaired t-test), and had more evaporated sweat (H=-106.1±4.59 W·m−2vs N=-91.15±3.24 W·m−2, P=0.01, unpaired t-test) than the normotensive subjects during the period of recovery from exercise. In conclusion, essential hypertensive subjects showed greater sweat evaporation and increased heat dissipation and body cooling relative to normotensive subjects during recovery from moderate-intensity exercise performed in hot conditions.


Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Regulación de la Temperatura Corporal/fisiología , Ambiente , Ejercicio Físico/fisiología , Calor , Hipertensión/fisiopatología , Presión Arterial/fisiología , Frecuencia Cardíaca , Consumo de Oxígeno/fisiología , Carrera/fisiología , Sudor/fisiología
9.
Braz J Med Biol Res ; 48(12): 1122-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26517335

RESUMEN

Individuals with systemic arterial hypertension have a higher risk of heat-related complications. Thus, the aim of this study was to examine the thermoregulatory responses of hypertensive subjects during recovery from moderate-intensity exercise performed in the heat. A total of eight essential hypertensive (H) and eight normotensive (N) male subjects (age=46.5±1.3 and 45.6±1.4 years, body mass index=25.8±0.8 and 25.6±0.6 kg/m2, mean arterial pressure=98.0±2.8 and 86.0±2.3 mmHg, respectively) rested for 30 min, performed 1 h of treadmill exercise at 50% of maximal oxygen consumption, and rested for 1 h after exercise in an environmental chamber at 38°C and 60% relative humidity. Skin and core temperatures were measured to calculate heat exchange parameters. Mean arterial pressure was higher in the hypertensive than in the normotensive subjects throughout the experiment (P<0.05, unpaired t-test). The hypertensive subjects stored less heat (H=-24.23±3.99 W·m-2vs N=-13.63±2.24 W·m-2, P=0.03, unpaired t-test), experienced greater variations in body temperature (H=-0.62±0.05°C vsN=-0.35±0.12°C, P=0.03, unpaired t-test), and had more evaporated sweat (H=-106.1±4.59 W·m-2vs N=-91.15±3.24 W·m-2, P=0.01, unpaired t-test) than the normotensive subjects during the period of recovery from exercise. In conclusion, essential hypertensive subjects showed greater sweat evaporation and increased heat dissipation and body cooling relative to normotensive subjects during recovery from moderate-intensity exercise performed in hot conditions.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Ambiente , Ejercicio Físico/fisiología , Calor , Hipertensión/fisiopatología , Adulto , Presión Arterial/fisiología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Carrera/fisiología , Sudor/fisiología
10.
Hemoglobin ; 22(3): 197-207, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9629495

RESUMEN

The development of methodologies to identify the molecular lesions responsible for different types of beta-thalassemia has made it possible to correlate these data with clinical and hematological severity. We examined DNA from 35 patients with beta-thalassemia, residents of the State of São Paulo, Brazil, for some types of genetic modifying factors: beta-thalassemia mutations, the upstream Xmnl GY-globin gene polymorphisms, and alpha-globin gene deletions. Additionally, the beta-like gene cluster haplotypes and the presence of the AYT variant were studied. The following mutations were present in the 70 chromosomes studied: 54.3% codon 39 (C-->T) (beta degree); 18.6% IVS-I-6 (T-->C) (beta+); 18.6% IVS-I-110 (G-->A) (beta+), and 4.3% IVS-I-1 (G-->T) (beta degree). Haplotype II was associated with the nonsense mutation at codon 39, haplotype I with the IVS-I-110 and codon 39 mutations, and haplotypes VI and VII with the IVS-I-6 mutation. The Xmnl polymorphism was detected in three out of 31 patients studied. No alpha-thalassemia was detected among the thalassemia intermedia patients. The AYT variant was present in 87.1% of 31 thalassemia patients and was associated with the codon 39/haplotype II and IVS-I-6/haplotype VI mutations. This is the first study of the Brazilian population that has analyzed the beta-thalassemia mutations and other molecular variants, and has correlated them with the clinical manifestations.


Asunto(s)
Talasemia beta/genética , Adolescente , Adulto , Alelos , Brasil , Niño , Preescolar , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Variación Genética , Globinas/genética , Haplotipos/genética , Humanos , Lactante , Mutación Puntual/genética
11.
Sao Paulo Med J ; 116(6): 1879-81, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10349197

RESUMEN

CONTEXT: Spinal cord compression due to extramedullary hematopoiesis is a well-described but rare syndrome encountered in several clinical hematologic disorders, including beta-thalassemia. CASE REPORT: We report the case of a patient with intermediate beta-thalassemia and crural paraparesis due to spinal cord compression by a paravertebral extramedullary mass. She was successfully treated with low-dose radiotherapy and transfusions. After splenectomy, she was regularly followed up for over four years without transfusion or recurrence of spinal cord compression. DISCUSSION: Extramedullary hematopoiesis should be investigated in patients with hematologic disorders and spinal cord symptoms. The rapid recognition and treatment with radiotherapy can dramatically alleviate symptoms.


Asunto(s)
Hematopoyesis Extramedular/efectos de la radiación , Compresión de la Médula Espinal/etiología , Compresión de la Médula Espinal/radioterapia , Talasemia beta/complicaciones , Adulto , Femenino , Estudios de Seguimiento , Humanos
12.
Rev. Assoc. Med. Bras. (1992) ; 41(3): 203-6, maio-jun. 1995. tab
Artículo en Portugués | LILACS | ID: lil-156297

RESUMEN

A sobrecarga de ferro (Fe) é problema cosmopolita, que tem a hemocromatose idiopática e a talassemia como as doenças genéticas a que maisfreqüentemente está associada. Enquanto a sobrecarga de ferro em beta-talassêmicos em hipertransfusäo é situaçäo bem definida, existindo esquemas terapêuticos que visam minorá-la, o mesmo näo acontece com a talassemia menor, na qual estoques de ferro aumentados têm sido encontrados, de forma näo consensual. A ferritinasérica é considerada o melhor índice para avaliaçäo do estoque do ferro, uma vezque existe correlaçäo entre os seus valores e a concentraçäo de ferro hepático. OBJETIVO. O presente trabalho tem por objetivo verificar o risco de traços talassêmicos desenvolverem sobrecarga de Fe e a correlaçäo entre o grau de anemia e oestado do ferro. MÉTODOS. Foram avaliados o Fe sérico, TIBC, saturaçäo de transferrina, ferritina e homeglobina de 35 talassêmicos menores assintomáticos e 35 indivíduos normais, pareados por sexo e idade (20 mulheres e 15 homens, entre 20 e 54 anos de idade). RESULTADOS. Näo houve diferença estatisticamente significante para nenhuma variável estudada nos grupos do sexo feminimo, diferentemente dosexo masculino, em que a ferritina sérica nos traços talassêmicos apresentou média de 253,69ng/mL, e no controle normal de 107,79ng/mL (U calc

Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Talasemia beta/sangre , Hierro/sangre , Electroforesis de las Proteínas Sanguíneas , Ferritinas/sangre , Hemoglobinometría , Técnicas para Inmunoenzimas , Factores Sexuales , Transferrina/análisis
13.
Rev Assoc Med Bras (1992) ; 41(3): 203-6, 1995.
Artículo en Portugués | MEDLINE | ID: mdl-8574230

RESUMEN

Idiopathic haemochromatosis and thalassemia are the most frequent genetic disorders associated to iron overload. In major and intermedia thalassemia patients, the iron overload is a well defined situation; however in minor thalassemia, frequently an asymptomatic disease, there is no agreement about the situation of iron storage. The best index for evaluation of the iron state is serum ferritin, because there is a correlation between its value and iron hepatic concentration. PURPOSE--Iron state was studied in a homogenous group of Brazilians with beta-thalassemia trait and the correlation between iron state and anemia severity was verified. METHODS--35 adult subjects with beta-thalassemia trait and 35 normal subjects (20 women and 15 men, aged between 20 to 54 years/group) were studied for serum iron, TIBC, serum ferritin and hemoglobin. RESULTS--The results demonstrated that in the male group of beta-thalassemia trait subjects the mean value of serum ferritin was 253.69ng/mL and in the male control group it was 107.79ng/mL (U calc < U crit). There was no statistic difference between any studied variable in female groups. There was no correlation between the iron state and the hemoglobin levels in beta-thalassemia trait subjects. CONCLUSION--The possibility of iron overload in males with beta-thalassemia trait and the necessity to follow-up those subjects with high levels of serum ferritin is suggested.


Asunto(s)
Hierro/sangre , Talasemia beta/sangre , Adulto , Femenino , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Talasemia beta/genética
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