RESUMO
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.
Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Citocinas/sangue , Hipertensão/fisiopatologia , Pressão Arterial/fisiologia , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Frequência Cardíaca/fisiologia , Temperatura Alta , Hipertensão/sangue , Inflamação/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
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.
Assuntos
Citocinas/sangue , Temperatura Alta , Hipertensão/fisiopatologia , Adulto , Pressão Arterial/fisiologia , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/sangue , Inflamação/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Masculino , Pessoa de Meia-Idade , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
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.
Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Regulação da Temperatura Corporal/fisiologia , Meio Ambiente , Exercício Físico/fisiologia , Temperatura Alta , Hipertensão/fisiopatologia , Pressão Arterial/fisiologia , Frequência Cardíaca , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Suor/fisiologiaRESUMO
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.
Assuntos
Regulação da Temperatura Corporal/fisiologia , Meio Ambiente , Exercício Físico/fisiologia , Temperatura Alta , Hipertensão/fisiopatologia , Adulto , Pressão Arterial/fisiologia , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Corrida/fisiologia , Suor/fisiologiaRESUMO
A laboratory model of myiasis as a result of Dermatobia hominis (L.) larvae was developed using mice as hosts. Mice in three groups were each infested with one newly hatched larva and skin biopsies processed for histopathology at 4, 12, and 20 d postinfestation (dpi). Mice in three other groups were each subjected to implantation of one larva collected from an infested (donor) mouse at 4, 12, and 20 dpi. Skin lesions of these receptor mice were then assessed at 10, 14, and 6 d postimplantation (dpimp), respectively. The inflammatory process in infested mice at 4 dpi was discrete, consisting of a thin necrotic layer around the larva, edema, many neutrophils, few eosinophils, mast cells, and proliferation of fibroblasts. At 12 dpi, there was a thicker necrotic layer, edema, many neutrophils and eosinophils, few mast cells, neoformation of capillaries, proliferation of the endothelium and fibroblasts, and early stages of fibrosis. These histopathological characteristics together with fibrosis were observed over a large area of the lesion at 20 dpi. Mice submitted to larval implantations demonstrated similar skin histopathology to that seen in the infested rodents, 10 dpimp corresponding to 12 dpi and 6 or 14 dpimp to 20 dpi. In all mice, the progressive acute inflammatory process followed a sequence linked to factors such as size of larvae and presence of secretory-excretory products. Both infested mice and those implanted experimentally with D. hominis larvae were shown to be suitable models for the study of the parasite-host relationship in this important zoonotic myiasis.
Assuntos
Dípteros/fisiologia , Modelos Animais de Doenças , Miíase/patologia , Pele/patologia , Animais , Dípteros/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Larva/fisiologia , Camundongos , Miíase/imunologia , Miíase/parasitologia , Pele/imunologia , Pele/parasitologiaRESUMO
BACKGROUND: Epidemiological data suggest that calcium intake may influence lipid metabolism. It is unknown whether this influence also occurs in individuals with HIV/AIDS. The present study aimed to assess the relationship between dietary calcium, dairy food intake and metabolic parameters in individuals with HIV/AIDS. METHODS: A cross-sectional study was conducted with 100 individuals with HIV/AIDS. Calcium intakes and food group consumption were determined by a food 24-h dietary recall and a food frequency questionnaire, respectively. The level of physical activity was determined with the international physical activity questionnaire and metabolic syndrome (MS) was defined by National Cholesterol Education Program Adult Treatment Panel III (2001). Student's t-test, one-way analysis of variance and chi-square were used to compare the groups. RESULTS: The mean (SD) calcium intake was 559.5 (298.84) mg day(-1) and dairy food consumption was 1.73 (0.78) servings per day. Dietary calcium intake below 700 mg day(-1) had greater waist circumference, body mass index (BMI) but not significant and higher systolic blood pressure (SBP) (P < 0.05) and diastolic blood pressure (DBP) (P = 0.07). Dairy food consumers (>2 servings per day) showed lower BMI (P < 0.01), waist circumference (P = 0.05), SBP and DBP (P < 0.05). There was a significant association between calcium intake, MS and hypertension. The odds ratio for MS was 2.0 [95% confidence interval (CI) = 1.23-3.32] and for hypertension was 2.25 (95% CI = 1.44-4.44). Only 21% of the individuals were categorised in the moderate/intense physical activity level. CONCLUSIONS: The results obtained suggest that a dietary pattern with higher proportion of calcium and fruits/vegetables may protect against abdominal obesity and hypertension in HIV-infected individuals.
Assuntos
Cálcio da Dieta/administração & dosagem , Laticínios , Infecções por HIV/complicações , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/prevenção & controle , Adulto , Idoso , Índice de Massa Corporal , Brasil/epidemiologia , Estudos Transversais , Dieta , Feminino , Infecções por HIV/tratamento farmacológico , Hospitais Universitários , Humanos , Hipertensão/complicações , Hipertensão/prevenção & controle , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Atividade Motora , Obesidade Abdominal/complicações , Obesidade Abdominal/prevenção & controle , Prevalência , Inquéritos e Questionários , Circunferência da Cintura , Adulto JovemRESUMO
OBJECTIVES: To assess body weight changes, progression to overweight/obesity and investigate the associated factors among HIV/AIDS patients. METHODS: A retrospective study was conducted involving a sample group of 203 adults with HIV/AIDS. Medical records were used to gather demographic, clinical and anthropometric information. The variables were compared by Chi-square tests, Student's t tests and One-way analysis of variance. RESULTS: The majority of the individuals studied were men (72.4%) with an average age of 34.68 +/- 8.3 years, and time of HIV infection of 4.12 +/- 1.8 years. 63% of the patients gained weight. The greatest weight gain was observed among patients with lower CD4 cell count on admission (8.45 +/- 6.6 vs. 5.97 +/- 4.97) p = 0.019. 39/203 new cases of overweight/obesity were identified, with a progression rate of 19%. Men were more likely to progress to overweight (p < 0.001) and women to obesity (p < 0.001). A direct and significant relationship was observed between the BMI level on admission and being overweight/obese at the end of the study for individuals admitted with normal weight. CONCLUSIONS: The results of the study show that in the course of HIV infection overweight/obesity affected men and women admitted with normal weight, although a greater proportion of women progressed to obesity. A higher weight gain contributed in a negative manner to the presence of dyslipidemias in these patients. These data show the importance of monitoring body weight in the course of HIV/AIDS treatment, even in those individuals who present normal body weight.
Assuntos
Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Sobrepeso/induzido quimicamente , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adolescente , Adulto , Brasil , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/induzido quimicamente , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
Wistar rats (Rattus norvegicus) infested with Dermatobia hominis (L. Jr., 1781) had their axillary lymph nodes removed and histopathologically processed. Follicular hyperplasia in the germinal center was noted from 2 d postinfestation (dpi), exhibiting a high number of centerblasts, mitotic and apoptotic cells, and a thin parafollicular area. The paracortex showed hyperplasia rich in dendritic cells, immunoblasts, and endothelial venules, with diapedesis seen from 4 dpi onward. Hyperplasia of the medullar sinus also was first observed at this point, as well as dilated lymphatic sinus, lymph, macrophages, neutrophils, mast cells, and eosinophils. Medullar strings were expanded and filled with immunoblasts, mitotic cells, and plasmocytes. Lymphadenitis was not observed. The expression of mast cells was similar for both myiasis-affected and control rats but increased significantly (mastocytosis) at 7 and 15 d postlarval emergence (dple). Eosinophilia was observed at 4, 10, 15, 20, and 28 dpi as well as at 2, 7, and 15 dple, particularly on the last three observations of dpi and the earliest dple. This experimental approach allowed progressive tissue reactions in the lymph nodes to be monitored during myiasis, particularly those involving mast cells and eosinophils. These reactions abated and complete repair was observed at 60 dple.
Assuntos
Dípteros/crescimento & desenvolvimento , Eosinófilos/patologia , Doenças Linfáticas/parasitologia , Mastócitos/patologia , Miíase/patologia , Animais , Eosinófilos/imunologia , Linfonodos/imunologia , Linfonodos/patologia , Doenças Linfáticas/imunologia , Masculino , Mastócitos/imunologia , Miíase/imunologia , Ratos , Ratos WistarRESUMO
The purposes of this study were to determine: a) the incorporation of labeled [3H] arachidonic acid on the intestinal mucosa, the liver and plasma, after 1,3 and 5 hours of administration, b) preferential incorporation by different tissues, c) and the effects on experimental rats with thioacetamide-induced cirrhosis, after four weeks of a dietary supplementation with nucleotides and long-chain polyunsaturated fatty acids. 209 female Wistar rats were divided into two groups (control and TAA group). The TAA group was given 300 mg of thioacetamide/L, in their drinking water for four months. After this period, a sample of 6 rats were taken from each group and examined, to evaluate the biochemical and histological changes of the experimental model, and 36 rats were taken to determine the incorporation of radioactivity by the groups. The rest of the animals were divided into four subgroups. Each group, receiving a supplementary diet with only long-chain polyunsaturated fatty acids and/or nucleotides or neither, for 4 weeks. After four months of thioacetamide, the incorporation of the [3H] arachidonic acid showed: a) an increased within 3 h in the intestinal mucosa, b) a decreased in the liver after 3 to 5 h c) and a drastic decrease in the plasma after 3 to 5 h. With a dietary supplementation of long-chain polyunsaturated fatty acids and nucleotides combined, there was a decrease of accumulate [3H] arachidonic acid in the intestine and a increase in the liver and plasma. The simultaneous supply of dietary polyunsaturated fatty acids and nucleotides was beneficial in the reversal of abnormalities of the lipid metabolism, in this experimental model of liver cirrhosis.