Silk Fibroin Hydrogels Incorporated with the Antioxidant Extract of Stryphnodendron adstringens Bark.

Barbatimão (Stryphnodendron adstringens) is a Brazilian medicinal plant known for its pharmacological properties, including healing activity related to its phenolic composition, which is chiefly given by tannins. In order to preserve its stability and bioactivity, barbatimão extracts can be incorporated into (bio-)polymeric matrixes, of which silk fibroin stands out due to its versatility and tunable properties. This work aimed to obtain barbatimão bark extract rich in phenolic compounds and evaluate its incorporation in fibroin hydrogels. From the extraction process, it was observed that the PG (propylene glycol) extract presented a higher global yield (X0) and phenolic compounds (TPC) than the ET (ethanol) extract. Furthermore, the antioxidant activity (ORAC and FRAP) was similar between both extracts. Regarding the hydrogels, morphological, chemical, thermal, and mechanical characterizations were performed to understand the influence of the barbatimão extract and the solvent on the fibroin hydrogel properties. As a result, the hydrogels containing the barbatimão PG extract (BT/PG hydrogels) showed the better physical-chemical and structural performance. Therefore, these hydrogels should be further investigated regarding their potential in medical and pharmaceutical applications, especially in wound healing.

Augmented muscle vasodilatory responses in obese children with Glu27 beta-2-adrenoceptor polymorphism.

This study examined forearm vasodilatation during mental challenge and exercise in 72 obese children (OC; age = 10 +/- 0.1 years) homozygous with polymorphism in the allele 27 of the beta-2-adrenoceptors: Gln27 (n = 61) and Glu27 (n = 11). Forearm blood flow was recorded during 3 min of each using the Stroop color-word test (MS) and handgrip isometric exercise. Baseline hemodynamic and vascular measurements were similar. During the MS, peak forearm vascular conductance was significantly greater in group Glu27 (Delta = 0.35 +/- 0.4 vs. 0.12 +/- 0.1 units, respectively, p = .042). Similar results were found during exercise (Delta = 0.64 +/- 0.1 vs. 0.13 +/- 0.1 units, respectively, p = .035). Glu27 OC increased muscle vasodilatory responsiveness upon the MS and exercise.

[Obese children lipid profile: effects of hypocaloric diet and aerobic physical exercise]. / Perfil lipídico em crianças obesas: efeitos de dieta hipocalórica e atividade física aeróbica.

UNLABELLED: Diet and exercise help improve obese adults' lipid profile. However, their effect on obese children, the aim of the present study, is poorly known. Fifty obese children were studied into 2 paired groups: Group D (1,500 - 1,800 kcal diet: 55% carbohydrate, 30% fat, 15% protein), and Group DE (same diet + aerobic physical activity 1 hour/day 3 times a week). After 5 months BMI, triglycerides, total cholesterol (TC) and fractions were assessed. No change in triglycerides, TC and low-density lipoprotein cholesterol (LDL-C) levels were reported in both groups. However, high-density lipoprotein cholesterol (HDL-C) increased (+10.3%; p< 0.01) only in DE Group. Screening patients with TC > 170 mg/dL, LDL-C > 110 mg/dL and HDL-C < 35 mg/dL we had: similar reduction for TC in both groups (-6.0% x -6.0%; p= ns), LDL-C reduction in both groups (-14.2% x -13.5%; p= ns), and HDL-C increase only in DE Group (+10.0%; p< 0.05). CONCLUSIONS: 1) Hypocaloric diet (HD) + exercise, rather than diet only, increase obese children's HDL-C levels irrespective of baseline levels; 2) HD only and HD + exercise lead to TC and LDL-C reduction in obese children with TC and LDL-C above normal values.

Perfil lipídico em crianças obesas: efeitos de dieta hipocalórica e atividade física aeróbica / Obese children lipid profile: effects of hypocaloric diet and aerobic physical exercise

Dieta hipocalórica e atividade física aeróbia promovem perda de peso e melhora do perfil lipídico de adultos obesos, entretanto pouco se conhece em crianças obesas, sendo este o objetivo do trabalho. Estudamos cinqüenta crianças obesas e dividimos em dois grupos pareados: Grupo D (dieta com 55 por cento de carboidrato, 30 por cento de gordura e 15 por cento de proteína - 1.500 e 1.800 kcal) e Grupo DE (mesma dieta + atividade física aeróbia 1 hora por dia, três vezes por semana). Após cinco meses, avaliamos: índice de massa corpórea (IMC), triglicerídeos, colesterol total (CT) e frações. Nenhuma modificação foi observada nos triglicerídeos, CT e lipoproteína de baixa-densidade colesterol (LDL-C) em ambos os grupos. Houve, porém, aumento da lipoproteína de alta-densidade colesterol (HDL-C) apenas no grupo DE (+10,3 por cento, p< 0,01). Selecionando pacientes com CT > 170 mg/dL, LDL-C > 110 mg/dL e HDL-C < 35 mg/dL, observou-se redução semelhante do CT nos dois grupos (-6,0 por cento x -6,0 por cento; p= ns), assim como da LDL-C de ambos (-14,2 por cento x -13,5 por cento; p= ns), e um acréscimo da HDL-C apenas no grupo DE (+10,0 por cento; p< 0,05). Conclusões: 1) Dieta hipocalórica (DH) e atividade física aeróbia promovem aumento da HDL-C, independente do valor basal, em crianças obesas quando comparado à DH isoladamente; 2) DH isoladamente ou associada a exercício aeróbio reduz CT e LDL-C, quando estes estão em níveis acima do valor normal, em crianças obesas.

Diet and exercise training restore blood pressure and vasodilatory responses during physiological maneuvers in obese children.

BACKGROUND: The effects of diet and diet plus exercise training on muscle vasodilatation during physiological maneuvers in obese children are unknown. We tested the hypothesis that (1) blood pressure (BP) and forearm vascular conductance (FVC) responses during handgrip exercise and mental stress would be altered in obese children and (2) diet plus exercise training would restore BP and FVC responses during exercise and mental stress in obese children. METHODS AND RESULTS: Thirty-nine obese children (aged 10+/-0.2 years) were randomly divided into 2 groups: diet plus exercise training (n=21; body mass index [BMI]=28+/-0.5 kg/m2) and diet (n=18; BMI=30+/-0.4 kg/m2). Ten age-matched lean control children (BMI=17+/-0.5 kg/m2) were also studied. Forearm blood flow was measured by venous occlusion plethysmography. BP was monitored noninvasively. Handgrip exercise was performed at 30% maximal voluntary contraction for 3 minutes. Stroop color word test was performed for 4 minutes. Baseline BP was significantly higher and FVC was significantly lower in obese children. During exercise and mental stress, BP responses were significantly higher and FVC responses were significantly lower in obese children. Diet and diet plus exercise training significantly reduced body weight. Diet and diet plus exercise training significantly decreased BP levels during exercise and mental stress. Diet plus exercise training, in contrast to diet alone, significantly increased FVC responses during exercise (3.7+/-0.3 versus 5.6+/-0.4 U; P=0.01) and mental stress (3.5+/-0.5 versus 4.5+/-0.4 U; P=0.02). After diet plus exercise training, BP and FVC responses during exercise and mental stress were similar between obese children and the control group. CONCLUSIONS: Obesity exacerbates BP responses and impairs FVC responses during exercise and mental stress in children. Diet and exercise training restore BP and FVC responses in obese children.