ABSTRACT
Poly(vinyl alcohol) (P)/alginate (A)/MMT (M) (PAM) composite aerogels was modified through interpenetrating cross-linking of methyltriethoxysilane (Ms) or γ-aminopropyltriethoxysilane (K) and calcium ion (Ca2+) as a cross-linking agent, respectively. The compressive moduli of the cross-linked PAM/MsCa and PAM/KCa aerogels greatly increased to 17.4 and 22.1 MPa, approximately 10.5- and 8.2-fold of that of PAM aerogel, respectively. The limited oxygen index (LOI) values for PAM/MsCa and PAM/KCa composite aerogels increased from 27.0% of PAM aerogel to 40.5% and 56.8%. Compared with non-cross-linked PAM aerogel, the peak heat release rate (PHRR) of PAM/MsCa and PAM/KCa composite aerogels dramatically decreased by 34% and 74%, respectively, whereas the PAM/KCa aerogel presented better flame retardancy and lower smoke toxicity than the PAM/MsCa aerogel because of the release of more inert gases and the barrier action of more compact char layer during the combustion. The highly efficient flame-retardant PAM-based composite aerogels with excellent mechanical properties are promising as a sustainable alternative to traditional petroleum-based foams.
ABSTRACT
BACKGROUND: Pregnant women with a high triglyceride-glucose (TyG) index during early pregnancy may increase the risk of gestational diabetes mellitus (GDM), and dietary fiber could play an important role in glucose and lipid metabolism. However, no trials have tested the effects of dietary fiber on preventing GDM in women with a high TyG index. This study aims to investigate whether GDM can be prevented by dietary fiber supplementation in women with a TyG index ≥8.5 during early pregnancy (<20 weeks). METHODS: A randomized clinical trial was performed among 295 women with a TyG index ≥8.5 before 20 weeks of gestation, divided into a fiber group (24 g dietary fiber powder/day) or a control group (usual care). The intervention was conducted from 20 to 24+6 gestational weeks, and both groups received guidance on exercise and diet. The primary outcomes were the incidence of GDM diagnosed by a 75 g oral glucose tolerance test at 25-28 gestational weeks, and levels of maternal blood glucose, lipids. Secondary outcomes include gestational hypertension, postpartum hemorrhage, preterm birth, and other maternal and neonatal complications. RESULTS: GDM occurred at 11.2% (10 of 89) in the fiber group, which was significantly lower than 23.7 (44 of 186) in the control group (P = 0.015). The mean gestational weeks increased dramatically in the fiber group compared with the control group (39.07 ± 1.08 vs. 38.58 ± 1.44 weeks, P = 0.006). The incidence of preterm birth was 2.3% (2 of 86) of women randomized to the fiber group compared with 9.4% (17 of 181) in the control group (P = 0.032). The concentrations of 2 h postprandial blood glucose showed statistically higher in the control group compared with the intervention group (6.69 ± 1.65 vs. 6.45 ± 1.25 mmol/L, P = 0.026). There were no other significant differences between groups in lipid profile values, or other secondary outcomes. CONCLUSION: An intervention with dietary fiber supplementation during pregnancy may prevent GDM and preterm birth in women with a TyG index ≥8.5 before 20 weeks of gestation.
Subject(s)
Diabetes, Gestational , Premature Birth , Pregnancy , Female , Infant, Newborn , Humans , Diabetes, Gestational/prevention & control , Blood Glucose , Triglycerides , Dietary FiberABSTRACT
SCOPE: To investigate whether dietary fiber supplementation may reduce the risk of gestational diabetes mellitus (GDM) in advanced maternal age Chinese women (≥35 years). Secondary outcomes include glucose metabolism, diet change, weight gain, and maternal and neonatal outcomes. METHODS AND RESULTS: In a randomized controlled trial, a dietary fiber group (19.56 g day-1 ) or control group (standard prenatal care) was conducted from 20 to 24+6 gestational weeks in advanced maternal age women. Dietary intakes were assessed using a validated 39-item Food Frequency Questionnaire (FFQ). GDM was diagnosed by a 75 g oral glucose tolerance test (OGTT) at 25-28 weeks. After intervention, the incidence of GDM was not significantly different between groups (21.6% vs 12.9%, p = 0.165). The mean increased in carbohydrate intake in the dietary fiber group is significantly lower than in the control group (-0.94 ± 92.12 g vs 32.27 ± 91.81 g, p = 0.032). In addition, the glucose tolerance, weight gain between 20 and 25 weeks, and preterm birth in the intervention group have improved compared to the control group. CONCLUSION: Supplementation with dietary fiber during pregnancy among advanced maternal age Chinese women do not lower the incidence of GDM, but improve glucose metabolism, gestational weight gain, and preterm birth.