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1.
Int J Biol Macromol ; 263(Pt 2): 130465, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38423427

ABSTRACT

In this research, a highly efficient adsorbent biomaterial (hereinafter, CTS/PPS-HS) of chitosan/functionalized fruit stones (peach and plum) with H2SO4 was produced for the adsorption of brilliant green (BG) dye from aquatic systems. The developed biomaterial was characterized by several techniques like SEM-EDX, FTIR, XRD, BET, and pHpzc. To systematically optimize the adsorption performance of CTS/PPS-HS, the Box-Behnken design (BBD) based on response surface methodology (RSM) was attained. The factors considered for optimization included A: CTS/PPS-HS dosage (0.02-0.08 g), B: pH (4-10), and C: removal time (10-60 min). The pseudo-first-order and Langmuir isotherm models exhibited excellent agreement with the experimental results of BG adsorption by CTS/PPS-HS. The outstanding adsorption capacity (409.63 mg/g) of CTS/PPS-HS was obtained. The remarkable adsorption of BG onto CTS/PPS-HS can be primarily attributed to electrostatic forces between the acidic sites of CTS/PPS-HS and the BG cations, accompanied by interactions such as π-π, Yoshida H-bonding, n-π, and H-bond interactions. The current data underscores the significant potential inherent in combining biomass with CTS polymer to create an exceptionally effective adsorbent biomaterial tailored for the elimination of cationic dyes.


Subject(s)
Chitosan , Quaternary Ammonium Compounds , Water Pollutants, Chemical , Coloring Agents/chemistry , Adsorption , Chitosan/chemistry , Biocompatible Materials , Fruit , Water Pollutants, Chemical/chemistry , Kinetics , Hydrogen-Ion Concentration
2.
Int J Biol Macromol ; 261(Pt 2): 129964, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38316327

ABSTRACT

This study aimed to develop a biocomposite (hereinafter, CHI/OP-H2SO4) via the functionalization of chitosan (CHI) biopolymer by chemically modified orange peel (OP-H2SO4). The physicochemical characteristics of CHI/OP-H2SO4 were studied using methods such as pHpzc, XRD, FTIR, BET, and FESEM-EDX. The efficacy of the CHI/OP-H2SO4 biocomposite in removing cationic dye (safranin O, SAF-O) from aqueous solutions was assessed. The Box-Behnken Design (BBD) based on response surface methodology (RSM) was employed to optimize the adsorption performance of CHI/OP-H2SO4, considering factors such as A: CHI/OP-H2SO4 dose (0.02-0.08 g), B: pH (4-10), and C: time (10-60 min). The pseudo-first-order and Freundlich isotherm models align well with the experimental data of SAF-O adsorption by CHI/OP-H2SO4. The excellent adsorption capacity for CHI/OP-H2SO4 was recorded (321.2 mg/g). The notable adsorption of SAF-O onto CHI/OP-H2SO4 is attributed primarily to electrostatic forces between the acidic groups of CHI/OP-H2SO4 and the SAF-O cation, along with H-bonding, and n-π interactions. By transforming waste materials into valuable resources, this approach not only mitigates environmental impact but also produces a promising and sustainable adsorbent for the removal of cationic dyes, exemplified here by the effective removal of SAF-O dye.


Subject(s)
Chitosan , Citrus sinensis , Phenazines , Water Pollutants, Chemical , Coloring Agents , Adsorption , Hydrogen-Ion Concentration , Kinetics
3.
Polymers (Basel) ; 15(13)2023 Jun 29.
Article in English | MEDLINE | ID: mdl-37447529

ABSTRACT

A designer of sustainable biocomposite structures and natural ropes needs to have a high confidence interval (95% CI) for mechanical characteristics data of performance materials, yet qualities for plant-based fibers are very diverse. A comprehensive study of the elements that enhance the performance of biocomposites or sustainable ropes created from vegetable fibers is necessary. The current study included five groups with varying numbers (N) of tests of 20, 40, 60, 80, and 100 on the mechanical characteristics at room temperatures. The purpose of this study was to determine how changing N affects the mechanical properties of sisal yarn. These properties include its strength, Young's modulus, and deformation at rupture. A significance testing program including more than 100 tests was performed. Owing to the heterogeneity of the plant yarn, each group received more than 20 samples at a gauge length (GL) of 100 mm. The tensile strength characteristics of sisal yarns produced a wide range of findings, as is common for natural fibers, necessitating a statistical analysis. Its dispersion was explored and measured using the statistical methods. The Weibull distribution with two parameters and a prediction model with a 95% confidence level for maximum likelihood (ML) and least squares (LS) were used to investigate and quantify its dispersion.

4.
Polymers (Basel) ; 15(13)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37447555

ABSTRACT

In this research work, we aim to study the effect of the incorporation of vegetable fiber reinforcement on the thermo-mechanical and dynamic properties of a composite formed by a polymeric matrix reinforced with cellulosic fibers with the various Washingtonia fiber (WF) loadings (0%, 10%, 20%, and 30% by wt%) as reinforced material in high-density polyethylene (HDPE) Biocomposites to evaluate the optimum fiber loading of biocomposites. In addition, several characterization techniques (i.e., thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermal mechanical analysis (TMA)) were used to better understand the characteristics of the new composites prepared. With these techniques, we managed to verify the rigidity and thermal stability of the composites so elaborated, as well as the success of the polymer and the structural homogeneity of the obtained biocomposites. Hence, the biocomposite with the best ratio (HDPE/20WF) showed a loss modulus (E″) of 224 MPa, a storage modulus (E') of 2079 MPa, and a damping factor (Tanδ) of 0.270 to the glass transition (Tg) of 145 °C. In addition, thermomechanical analysis (TMA) of the biocomposite samples exhibited marginally higher Ts compared to the HDPE matrix. The best results were recorded with biocomposites with 20% WF, which showed better thermal properties. This composite material can be used as insulation in construction materials (buildings, false ceilings, walls, etc.).

5.
Polymers (Basel) ; 15(10)2023 May 11.
Article in English | MEDLINE | ID: mdl-37242850

ABSTRACT

Fiber-reinforced plastic composites are sensitive to holes, as they cut the main load-carrying member in the composite (fibers) and they induce out-of-plane stresses. In this study, we demonstrated notch sensitivity enhancement in a hybrid carbon/epoxy (CFRP) composite with a Kevlar core sandwich compared to monotonic CFRP and Kevlar composites. Open-hole tensile samples were cut using waterjet cutting at different width to diameter ratios and tested under tensile loading. We performed an open-hole tension (OHT) test to characterize the notch sensitivity of the composites via the comparison of the open-hole tensile strength and strain as well as the damage propagation (as monitored via CT scan). The results showed that hybrid laminate has lower notch sensitivity than CFRP and KFRP laminates because the strength reduction rate with hole size was lower. Moreover, this laminate showed no reduction in the failure strain by increasing the hole size up to 12 mm. At w/d = 6, the lowest drop in strength showed by the hybrid laminate was 65.4%, followed by the CFRP and KFRP laminates with 63.5% and 56.1%, respectively. For the specific strength, the hybrid laminate showed a 7% and 9% higher value as compared with CFRP and KFRP laminates, respectively. The enhancement in notch sensitivity was due to its progressive damage mode, which was initiated via delamination at the Kevlar-carbon interface, followed by matrix cracking and fiber breakage in the core layers. Finally, matrix cracking and fiber breakage occurred in the CFRP face sheet layers. The specific strength (normalized strength and strain to density) and strain were larger for the hybrid than the CFRP and KFRP laminates due to the lower density of Kevlar fibers and the progressive damage modes which delayed the final failure of the hybrid composite.

6.
Health Promot Chronic Dis Prev Can ; 42(8): 344-352, 2022 Aug.
Article in English, French | MEDLINE | ID: mdl-35993604

ABSTRACT

INTRODUCTION: Northern communities in Canada experience a disproportionate burden of chronic diseases including mental illness. To mitigate the growing health inequalities, an ongoing Comprehensive School Health program promoting healthy lifestyle behaviours and mental health and well-being was expanded to rural and remote northern communities. We report on the program's impact on knowledge, attitudes, lifestyle behaviours (healthy eating, physical activity, screen time), weight status and the mental health and well-being of elementary school students during the first four years of implementation. METHODS: Following a repeated cross-sectional design, we surveyed 440, 352 and 384 Grade 4 to 6 students (9-12 years old) from eight schools in 2016, 2018 and 2020/21, respectively. Students were approximately equally represented by girls and boys. RESULTS: Between 2016 and 2018, students reported modest increases in vegetable and fruit consumption and dietary variety; declines in screen time; no changes in physical activity; and declines in attitudes toward healthy lifestyle and in mental health and well-being. Between 2018 and 2020/21, lifestyle behaviours deteriorated substantially, while attitudes and mental health and well-being continued to decline. CONCLUSION: A program that was successful in socioeconomically disadvantaged urban neighbourhoods had a favourable, though modest, impact on selected lifestyle behaviours, but not on attitudes and mental health and well-being, in rural and remote northern communities. In light of cultural differences and logistical challenges in Canada's North, systematic and proactive adaptations to local contexts, increased intensity, and longer program delivery are essential to facilitate sustainable improvements in lifestyle behaviours and mental health and well-being.


Subject(s)
Rural Population , Schools , Child , Cross-Sectional Studies , Female , Health Promotion , Humans , Male , Vegetables
7.
Materials (Basel) ; 15(11)2022 Jun 05.
Article in English | MEDLINE | ID: mdl-35683307

ABSTRACT

This study is focused on the kinetics and adsorption isotherms of amine-functionalized magnesium ferrite (MgFe2O4) for treating the heavy metals in wastewater. A sol-gel route was adopted to produce MgFe2O4 nanoparticles. The surfaces of the MgFe2O4 nanoparticles were functionalized using primary amine (ethanolamine). The surface morphology, phase formation, and functionality of the MgFe2O4 nano-adsorbents were studied using the SEM, UV-visible, FTIR, and TGA techniques. The characterized nanoparticles were tested on their ability to adsorb the Pb2+, Cu2+, and Zn2+ ions from the wastewater. The kinetic parameters and adsorption isotherms for the adsorption of the metal ions by the amine-functionalized MgFe2O4 were obtained using the pseudo-first-order, pseudo-second-order, Langmuir, and Freundlich models. The pseudo-second order and Langmuir models best described the adsorption kinetics and isotherms, implying strong chemisorption via the formation of coordinative bonds between the amine groups and metal ions. The Langmuir equation revealed the highest adsorption capacity of 0.7 mmol/g for the amine-functionalized MgFe2O4 nano-adsorbents. The adsorption capacity of the nanoadsorbent also changed with the calcination temperature. The MgFe2O4 sample, calcined at 500 °C, removed the most of the Pb2+ (73%), Cu2+ (59%), and Zn2+ (62%) ions from the water.

8.
Materials (Basel) ; 15(5)2022 Feb 26.
Article in English | MEDLINE | ID: mdl-35268995

ABSTRACT

The optical properties and electric field enhancement of gold nanorods for different cases were investigated in this study. The numerical analysis was carried out to understand the functionality and working of gold nanorods, while the experimental portion of the work was focused on the efficiency of gold nanorods for targeted drug delivery. COMSOL Multiphysics was used for numerical analysis. The theoretical results suggest the use of gold nanorods (AuNRs) for anticancer applications. The resonance peaks for gold nanorods of 10 nm diameter were observed at 560 nm. The resonance peaks shifted towards longer wavelengths with an increase in nanorod size. The resonance peaks showed a shift of 140 nm with a change in nanorod length from 25 to 45 nm. On the experimental side, 22 nm, 35 nm and 47 nm long gold nanorods were produced using the seed-mediated growth method. The surface morphology of the nanorods, as well as their optical characteristics, were characterized. Later, gold nanorods were applied to the targeted delivery of the doxorubicin drug. Gold nanorods showed better efficiency for doxorubicin drug loading time, release time, loading temperature, and release temperature. These results reveal that AuNRs@DA possess good ability to load and deliver the drug directly to the tumorous cells since these cells show high temperature and acidity.

9.
Public Health ; 202: 35-42, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34879321

ABSTRACT

OBJECTIVES: The closure of schools to prevent the spread of COVID-19 prompted concerns of deteriorating lifestyle behaviours, mental health, and wellbeing of children, particularly those in socioeconomically disadvantaged settings. We assessed changes in lifestyle behaviours (physical activity, screen time, eating habits and bed/wake-up times), mental health and wellbeing during the first lockdown in Spring 2020 as perceived by school children from disadvantaged settings, and examined determinants of these changes. STUDY DESIGN: Cross-sectional study. METHODS: We surveyed 1095 grade 4 to 6 students (age 9-12 years) from 20 schools in socioeconomically disadvantaged communities in northern Canada. Students reported on changes in lifestyle behaviours, mental health and wellbeing during the lockdown. Determinants of these perceived changes were examined in multivariable regression models. RESULTS: A majority of students reported declines in physical activity, having late bed/wake-up times, and modest improvements in mental health and wellbeing. Many students reported increases rather than decreases in screen time and snacking. Positive attitudes toward being active, eating healthy, going to sleep on time and being healthy were strongly associated with maintaining healthy lifestyle behaviours during the lockdown. Positive attitudes toward active and healthy living and healthy lifestyle behaviours were associated with maintaining positive mental health and wellbeing during the lockdown. CONCLUSIONS: The considerable changes in lifestyle behaviors, superimposed on the pre-existing burden of unhealthy lifestyle behaviours, put this generation of children at increased risk for future chronic disease. Findings call for effective health promotion of active and healthy lifestyles to benefit both physical and mental health.


Subject(s)
COVID-19 , Mental Health , Child , Communicable Disease Control , Cross-Sectional Studies , Humans , Life Style , SARS-CoV-2 , Schools
10.
PLoS One ; 15(8): e0236559, 2020.
Article in English | MEDLINE | ID: mdl-32817636

ABSTRACT

Chronic obstructive pulmonary disease (COPD) poses a significant but heterogeneous burden to individuals and healthcare systems. Policymakers develop targeted policies to minimize this burden but need personalized tools to evaluate novel interventions and target them to subpopulations most likely to benefit. We developed a platform to identify subgroups that are at increased risk of emergency department visits, hospitalizations and mortality and to provide stratified patient input in economic evaluations of COPD interventions. We relied on administrative and survey data from Ontario, Canada and applied a combination of microsimulation and multi-state modeling methods. We illustrated the functionality of the platform by quantifying outcomes across smoking status (current, former, never smokers) and by estimating the effect of smoking cessation on resource use and survival, by comparing outcomes of hypothetical cohorts of smokers who quit at diagnosis and smokers that continued to smoke post diagnosis. The cumulative incidence of all-cause mortality was 37.9% (95% CI: 34.9, 41.4) for never smokers, 34.7% (95% CI: 32.1, 36.9) for current smokers, and 46.4% (95% CI: 43.6, 49.0) for former smokers, at 14 years. Over 14 years, smokers who did not quit at diagnosis had 16.3% (95% CI: 9.6, 38.4%) more COPD-related emergency department visits than smokers who quit at diagnosis. In summary, we combined methods from clinical and economic modeling to create a novel tool that policymakers and health economists can use to inform future COPD policy decisions and quantify the effect of modifying COPD risk factors on resource utilization and morality.


Subject(s)
Patient Acceptance of Health Care/statistics & numerical data , Policy Making , Pulmonary Disease, Chronic Obstructive/mortality , Smoking Cessation/statistics & numerical data , Tobacco Smoking/adverse effects , Aged , Cost-Benefit Analysis , Female , Health Resources/economics , Hospitalization/statistics & numerical data , Humans , Male , Middle Aged , Models, Theoretical , Non-Smokers/statistics & numerical data , Ontario , Retrospective Studies , Risk Factors , Smokers/statistics & numerical data
11.
Med Chem ; 14(6): 626-640, 2018.
Article in English | MEDLINE | ID: mdl-29663896

ABSTRACT

BACKGROUND: Designing a novel antagonist against VEGFR-2 is being applied currently to inhibit cancer growth and metastasis. Because of the unexpected side effects incurred by the contemporary anticancer medications, the focus has been laid towards identifying natural compounds that might carry the potential to inhibit tumor progression. VEGR-2 remains an important target for anticancer drug development as it is the master regulator of vascular growth. OBJECTIVE: The study focuses on virtual screening of compounds from plants of Asteraceae family that bears antiangiogenic potential and thus, inhibiting VEGFR-2 using a computational approach. MATERIALS AND METHODS: Structures of phytochemicals were prepared using ChemDraw Ultra 10 software and converted into its 3D PDB structure and minimized using Discovery Studio client 2.5. The target protein, VEGFR-2 was retrieved from RCSB PDB. Lipinski's rule and ADMET toxicity profiling were carried out on the phytochemicals of the Asteraceae family and the filtered compounds were further promoted for molecular docking and MD simulation analysis. The study extends towards the SOM analysis of Pinocembrin to predict the possible toxic and non-toxic in vivo metabolites via in silico tools (Xenosite Web and PASS online server). RESULTS: The docking results revealed promising inhibitory potential of Pinocembrin against VEGFR-2 with binding energy of -8.50 kcal/mole as compared to its known inhibitors Sorafenib and YLT192 having binding energy of -6.49 kcal/mole and -8.02 kcal/mol respectively. Further, molecular dynamics (MD) simulations for 10ns were conducted for optimization, flexibility prediction, and determination of folded VEGFR-2 stability. The Hsp90-Pinocembrin complex was found to be quite stable with RMSD value of 0.2nm. Pinocembrin was found to be metabolically stable undergoing phase I metabolism with non-toxic metabolites compared to the standard drug Sorafenib and YLT192. CONCLUSION: Obtained results propose Pinocembrin as a multi-targeted novel lead compound that bears outstanding antiangiogenic potential against VEGFR-2.


Subject(s)
Angiogenesis Inhibitors/chemistry , Flavanones/chemistry , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors , Angiogenesis Inhibitors/metabolism , Angiogenesis Inhibitors/toxicity , Asteraceae/chemistry , Benzamides/pharmacology , Flavanones/metabolism , Flavanones/toxicity , HSP90 Heat-Shock Proteins/chemistry , Ligands , Molecular Docking Simulation , Molecular Dynamics Simulation , Niacinamide/analogs & derivatives , Niacinamide/pharmacology , Phenylurea Compounds/pharmacology , Picolinic Acids/pharmacology , Protein Binding , Sorafenib , Thermodynamics , Vascular Endothelial Growth Factor Receptor-2/chemistry
12.
Matern Child Health J ; 21(4): 705-714, 2017 04.
Article in English | MEDLINE | ID: mdl-27449649

ABSTRACT

Objectives To study the independent effect of pre-pregnancy weight, gestational weight gain (GWG), and other important risk factors on newborn birth weight. Methods Baseline data of 435 adult women and their singletons born between January and February 2012 at a public hospital in Brazil were used. Logistic regression was applied to determine the independent importance of pre-pregnancy weight and GWG for large for gestational age (LGA) newborns. Results Among all mothers, 37.9 % were overweight and obese before pregnancy and 45.3 % experienced excessive GWG. Among the newborns, 24.4 % were classified as LGA. Univariate analysis showed an association of family income, GWG, pre-pregnancy BMI and excessive GWG with LGA newborns. Smoking before and during pregnancy was associated with a decreased likelihood of giving birth to an LGA newborn compared to mothers who did not smoke. After adjustment for confounding variables, age at birth of first child, GWG, HbA1c and pre-pregnancy weight-GWG were significant and independent determinants of giving birth to an LGA newborn. Mothers with pre-pregnancy overweight and excessive GWG were more likely to deliver an LGA newborn (OR 2.54, P < 0.05) compared to mothers who were normal weight and experienced adequate GWG. Conclusions for Practice Age at first birth of child, GWG, HbA1c and pre-pregnancy overweight combined with excessive GWG are independent determinants of LGA newborns. The results of this study suggest that both primary prevention of overweight in women of childbearing age and management of GWG may be important strategies to reduce the number of LGA newborns and, consequently, the long-term public health burden of obesity.


Subject(s)
Birth Weight , Fetal Macrosomia/etiology , Fetal Macrosomia/prevention & control , Overweight/complications , Pregnant Women , Weight Gain , Adult , Body Mass Index , Brazil , Female , Humans , Infant, Newborn , Logistic Models , Male , Middle Aged , Pregnancy , Risk Factors
13.
J Sleep Res ; 26(4): 468-476, 2017 08.
Article in English | MEDLINE | ID: mdl-27734569

ABSTRACT

Both diet quality and sleep duration of children have declined in the past decades. Several studies have suggested that diet and sleep are associated; however, it is not established which aspects of the diet are responsible for this association. Is it nutrients, food items, diet quality or eating behaviours? We surveyed 2261 grade 5 children on their dietary intake and eating behaviours, and their parents on their sleep duration and sleep quality. We performed factor analysis to identify and quantify the essential factors among 57 nutrients, 132 food items and 19 eating behaviours. We considered these essential factors along with a diet quality score in multivariate regression analyses to assess their independent associations with sleep. Nutrients, food items and diet quality did not exhibit independent associations with sleep, whereas two groupings of eating behaviours did. 'Unhealthy eating habits and environments' was independently associated with sleep. For each standard deviation increase in their factor score, children had 6 min less sleep and were 12% less likely to have sleep of good quality. 'Snacking between meals and after supper' was independently associated with sleep quality. For each standard deviation increase in its factor score, children were 7% less likely to have good quality sleep. This study demonstrates that eating behaviours are responsible for the associations of diet with sleep among children. Health promotion programmes aiming to improve sleep should therefore focus on discouraging eating behaviours such as eating alone or in front of the TV, and snacking between meals and after supper.


Subject(s)
Diet , Eating , Feeding Behavior , Food , Sleep/physiology , Child , Diet Surveys , Female , Health Promotion , Humans , Male , Parents , Snacks , Time Factors
14.
Med Chem ; 13(3): 282-291, 2017.
Article in English | MEDLINE | ID: mdl-27834134

ABSTRACT

BACKGROUND: Angiogenesis involves the process of sprouting of microvessels from preexisting microvasculature and is held responsible for the growth, malignancy and metastasis of cancer. Heat shock protein Hsp90 has been proven responsible for indirectly inducing multiple pathways leading to angiogenesis and metastasis in cancer. Recent researches shift towards proposing novel phytochemicals as possible antiangiogenic agents. OBJECTIVE: The study aims towards Virtual screening of compounds from Cucurbitaceae family and their Druglikeliness and PreADMET filtering in search of potent lead as Vitexin, targeting Hsp90 and hence restraining angiogenesis. MATERIALS AND METHODS: Structures of phytochemicals from Cucurbitaceae family were retrieved from PubChem database and were converted into suitable 3-D structures. The target protein, Hsp90 was retrieved from RCSB Protein Data Bank. Phytochemicals of Cucurbitaceae family were filtered through enumerated Lipinski's rule of five and ADMET toxicity profiling and the filtered compounds were further taken forward for molecular docking analysis and interaction studies using AutoDock Tools 4.0. RESULTS: The docking results revealed Vitexin, a prominent glycosylated natural flavonoid, showing promising inhibitory potential against Hsp90 with binding energy of -8.80 kcal/mole and Ki 353.24 nM as compared to its known inhibitor Ganetespib having binding energy of -7.33 kcal/mole and Ki 4260 nM. Vitexin also exhibits better drug having properties with satisfactory ADMET profiling in relation to Ganetespib. CONCLUSION: The result proposes Vitexin to hold prominent antiangiogenic potential surpassing different in silico parameters and thus expected to be a multi-targeted novel antiangiogenic lead.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Apigenin/pharmacology , Cucumis sativus/chemistry , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Angiogenesis Inhibitors/chemistry , Angiogenesis Inhibitors/isolation & purification , Apigenin/chemistry , Apigenin/isolation & purification , Dose-Response Relationship, Drug , HSP90 Heat-Shock Proteins/metabolism , Humans , Molecular Conformation , Molecular Docking Simulation , Structure-Activity Relationship
15.
Can J Public Health ; 106(5): e277-82, 2015 Apr 30.
Article in English | MEDLINE | ID: mdl-26451988

ABSTRACT

OBJECTIVES: To describe sleep duration and sleep characteristics, and to examine the associations between sleep duration and characteristics and body weight status, diet quality, and physical activity levels among grade 5 children in Nova Scotia. METHODS: A provincially representative sample of 5,560 grade 5 children and their parents in Nova Scotia was surveyed. Parents were asked to report their child's bedtime and wake-up time, and to indicate how often their child snored or felt sleepy during the day. Dietary intake and physical activity were selfreported by children using the Harvard Youth/Adolescent Food Frequency Questionnaire and the Physical Activity Questionnaire for Children respectively. Body weight status was determined using measured heights and weights. Linear and logistic random effects models with children nested within schools were used to test for associations. RESULTS: Approximately half of the surveyed parents reported that their children were not getting adequate sleep at night. Longer sleep duration was statistically significantly associated with decreased risk for overweight and obesity independent of other sleep characteristics (OR = 0.82, 95% CI: 0.73, 0.91). Longer sleep duration was also associated with better diet quality and higher levels of physical activity. CONCLUSIONS: These findings indicate a need for health promotion strategies to encourage adequate sleep and to promote healthy sleep environments among children. Given the links among sleep, body weight status and lifestyle behaviours, these messages should be included in public health interventions aimed at preventing obesity and promoting health among children.


Subject(s)
Body Weight , Diet/standards , Motor Activity , Sleep , Child , Cross-Sectional Studies , Female , Humans , Male , Multivariate Analysis , Nova Scotia/epidemiology , Pediatric Obesity/epidemiology , Risk , Surveys and Questionnaires , Time Factors
16.
Ann Epidemiol ; 25(10): 753-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26303616

ABSTRACT

PURPOSE: Underestimating body size hinders healthy behavior modification needed to prevent obesity. However, initiatives to improve body size misperceptions may have detrimental consequences on self-esteem and self-efficacy. METHODS: Using sex-specific multiple mixed-effect logistic regression models, we examined the association of underestimating versus accurate body size perceptions with self-esteem and self-efficacy in a provincially representative sample of 5075 grade five school children. Body size perceptions were defined as the standardized difference between the body mass index (BMI, from measured height and weight) and self-perceived body size (Stunkard body rating scale). Self-esteem and self-efficacy for physical activity and healthy eating were self-reported. RESULTS: Most of overweight boys and girls (91% and 83%); and most of obese boys and girls (93% and 90%) underestimated body size. Underestimating weight was associated with greater self-efficacy for physical activity and healthy eating among normal-weight children (odds ratio: 1.9 and 1.6 for boys, 1.5 and 1.4 for girls) and greater self-esteem among overweight and obese children (odds ratio: 2.0 and 6.2 for boys, 2.0 and 3.4 for girls). CONCLUSIONS: Results highlight the importance of developing optimal intervention strategies as part of targeted obesity prevention efforts that de-emphasize the focus on body weight, while improving body size perceptions.


Subject(s)
Body Image/psychology , Diet/psychology , Exercise/psychology , Overweight/psychology , Self Concept , Body Mass Index , Body Size , Child , Female , Humans , Logistic Models , Male , Nova Scotia/epidemiology , Overweight/epidemiology , Pediatric Obesity/epidemiology , Pediatric Obesity/psychology , Residence Characteristics , Self Efficacy , Self Report , Socioeconomic Factors
17.
Matern Child Health J ; 19(9): 2048-56, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25656729

ABSTRACT

Breastfeeding has been rigorously studied in relation to childhood obesity prevention. Few studies have examined whether combination feeding­breast milk and formula­may also be protective against obesity. This study aimed to investigate the relationship between breastfeeding duration, combination feeding and overweight and obesity among Canadian school children. We analyzed data from a 2011 cross-sectional, population based survey (n = 5,560), which included self-reported infant feeding behaviours, a food frequency questionnaire and measured height and weight. Multilevel regression methods were used to examine the association between breastfeeding duration and overweight and obesity adjusting for socioeconomic status, diet quality and physical activity. Thirty-four percent of children were breastfed for <1 week or never while 32% were breastfed for at least 6 months. In the fully adjusted model, children who were only formula fed or who were combination fed for <6 months were more likely to be overweight or obese relative to children who were only breastfed (OR 1.29, 95% CI 1.04-1.60 and OR 1.35, 95% CI 1.09-1.69, respectively). When examining overweight and obese children separately, those who were only formula fed were more likely obese (OR 1.57, 95% CI 1.10-2.25) relative to their peers who were only breastfed. And those who were combination fed for <6 months relative to those only breastfed were more likely to be overweight (OR 1.29, 95% CI 1.01-1.66). Breastfeeding, in the absence of formula feeding, appears to have a protective effect on childhood obesity. While combination feeding confers less benefit than only breastfeeding, it is more desirable than formula feeding alone. Strategies and social policies are needed to promote exclusive and longer breastfeeding duration and should be integrated with comprehensive efforts to prevent childhood obesity and to reduce the burden of chronic diseases in the long term.


Subject(s)
Breast Feeding/statistics & numerical data , Feeding Behavior , Infant Formula/statistics & numerical data , Pediatric Obesity/epidemiology , Body Mass Index , Child , Cross-Sectional Studies , Female , Humans , Infant, Newborn , Male , Nova Scotia/epidemiology , Self Report
18.
Can J Public Health ; 105(6): e418-24, 2014 Nov 05.
Article in English | MEDLINE | ID: mdl-25560887

ABSTRACT

OBJECTIVE: Vitamin D intake in childhood is primarily for the prevention of rickets. Inconsistent evidence has associated adequate blood concentrations with a decreased risk of certain health conditions. Further, obese individuals may have lower vitamin D status. The estimated average requirement (EAR) for children recently doubled to 400 IU/day. Our aim was to examine dietary intake of vitamin D in different body mass index (BMI) categories, in addition to assessing determinants. METHODS: Data from two provincial surveys of grade 5 children, including a food frequency questionnaire and measured BMI, were used. Rao-Scott chi-square statistic tested the bivariate association between provinces and adequate dietary vitamin D intake. Key correlates were examined using multi-level logistic regression. RESULTS: Those below the EAR differed between Alberta (78%) and Nova Scotia (81%). Those drinking <2 glasses of milk/day had 0.02 times the odds of meeting the EAR (95% CI: 0.01-0.02) compared to those drinking more. No significant difference was observed for BMI, though those consuming <1 glass of milk/day were more likely to be obese than those consuming ≥2 glasses/day. Income and physical activity were negatively correlated with meeting the EAR. CONCLUSION: Many children did not meet the EAR for vitamin D from dietary sources and milk consumption was an important determinant. Given trends towards a more sedentary lifestyle and limited sun exposure, we recommend prioritizing public health efforts to support dietary vitamin D intake alongside interventions to increase physical activity and reduce sedentary behaviour. Further investigation is required to determine the need for targeted strategies for obese children.


Subject(s)
Diet/statistics & numerical data , Life Style , Pediatric Obesity , Vitamin D/administration & dosage , Body Mass Index , Canada , Child , Diet Surveys , Female , Humans , Logistic Models , Male , Multilevel Analysis , Recommended Dietary Allowances , Socioeconomic Factors
19.
Pharmacogn Mag ; 9(33): 51-7, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23661994

ABSTRACT

BACKGROUND: Dietary phytochemicals consist of a wide variety of biologically active compounds that are ubiquitous in plants, many of which have been reported to have anti-tumor as well as anti-inflammatory properties. OBJECTIVE: In the present study, we aimed to validate these findings by using docking protocols and explicate the possible mechanism of action for a dataset of nine phytochemicals namely boswellic acid, 1-caffeoylquinic acid, ellagic acid, emodin, genistein, guggulsterone, quercetin, resveratrol, and sylibinin from different plants against the nuclear factor- kappaB (NF-κB) precursor protein p105, an important transcription factor reported to be overexpressed in breast cancer. MATERIALS AND METHODS: 2-D structures of all phytochemicals were retrieved from PubChem Compound database and their subsequent conversion into 3-D structures was performed by using online software system CORINA. The X-ray crystallographic structure of the NF-κB precursor p105 was extracted from Brookhaven Protein Data Bank. Molecular docking simulation study was carried out by using AutoDock Tools 4.0. RESULTS: Our results showed significant binding affinity of different phytochemicals with the Rel homology domain of the NF-κB precursor protein p105. Quercetin and 1-caffeoylquinic acid were found to be very effective inhibitors against target molecule as they showed binding energy of -12.11 and -11.50 Kcal/mol, respectively. The order of affinity of other ligands with p105 was found as follows: guggulsterone > sylibinin > emodin > resveratrol > genistein > boswellic acid > ellagic acid. CONCLUSION: Our in silico study has explored the possible chemopreventive mechanism of these phytochemicals against the NF-κB precursor protein p105 and deciphered that quercetin, 1-caffeoylquinic acid and guggulsterone were the potent inhibitors against target molecule. In addition, large scale preclinical and clinical trials are needed to explore the role of these chemotherapeutic molecules against the NF-κB precursor protein p105 in cure and prevention of breast cancer.

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