Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
Add more filters










Publication year range
1.
Int J Eat Disord ; 55(12): 1670-1677, 2022 12.
Article in English | MEDLINE | ID: mdl-35833678

ABSTRACT

OBJECTIVE: The objective of this study is to examine the association between indicators of social adversity, including socioeconomic status and race/ethnicity, and children's disordered eating behaviors and attitudes. METHODS: Children ages 8-10 years old (n = 183) were recruited from Michigan. Data were collected through in-home surveys. The Children's Eating Attitudes Test (ChEAT-24) measured disordered eating attitudes and behaviors in the sample. Cumulative social adversity was considered the sum of four binary variables: caregiver race/ethnicity, caregiver education, household income, and child-reported food security status. Linear mixed models examined the association between social adversity indicators and ChEAT-24 scores. RESULTS: Children of primary caregivers of color had significantly higher ChEAT-24 scores than children of white caregivers (p = .03). Children who reported food insecurity had significantly higher ChEAT-24 scores compared to children who reported food security (p = .01). Compared to children with the lowest social adversity score, children with the highest score had a 4.8-unit higher ChEAT-24 score (95% CI .3-9.4), after adjusting for covariates. A significant trend was observed for greater social adversity and higher ChEAT-24 score (p-trend = .02). CONCLUSION: A linear association was observed between greater social adversity and more disordered eating behaviors and attitudes among children in this sample. These findings emphasize the need for eating disorder research in children from racial/ethnic minorities and socioeconomically disadvantaged populations to support future prevention efforts. PUBLIC SIGNIFICANCE: Greater exposure to social adversity was associated with more disordered eating behaviors among preadolescent children. Given that eating disorders are understudied in lower-income and minority racial/ethnic populations, this study highlights the need for additional research to better support prevention and treatment efforts among children from socioeconomically diverse backgrounds.


Subject(s)
Feeding and Eating Disorders , Minority Groups , Humans , Child , Social Class , Michigan , Feeding and Eating Disorders/diagnosis
2.
Int J Eat Disord ; 55(10): 1331-1341, 2022 10.
Article in English | MEDLINE | ID: mdl-35869930

ABSTRACT

OBJECTIVE: To examine the relation of caregiver-reported household food insecurity (FI) and child-reported FI with eating disorder (ED) risk factors and symptoms, including effect modification by gender, in preadolescent children. METHOD: Data were from the Family Food Study, a cross-sectional study of households with incomes ≤200% of the federal poverty line in southeastern Michigan. Children aged 8-10 years (n = 194) and their female primary caregivers reported separately on FI status. Children reported ED risk factors/symptoms via the 24-item Children's Eating Attitudes Test (ChEAT-24), with higher scores indicating more ED risk factors/symptoms. Linear mixed models were used to examine associations between FI measures with the ChEAT-24 total score, plus subscale scores for dieting, food preoccupation, weight preoccupation, vomiting, and social pressure to eat/gain weight. Models were adjusted for child age, child gender, caregiver race/ethnicity, caregiver education, and household income. RESULTS: Among all children, child-reported FI, but not caregiver-reported household FI, was associated with more ED risk factors/symptoms. Child-reported FI (vs. no FI) was associated with higher average ChEAT-24 total score (ß = 2.41, 95% CI: 0.57, 4.25). Child-reported FI was also associated with more food preoccupation, more weight preoccupation, and more social pressure to eat. Caregiver-reported household FI was marginally associated with less dieting in girls, and child-reported FI was associated with more dieting in boys. DISCUSSION: Child-reported FI may be more salient than caregiver-reported household FI as a risk factor for ED-related outcomes in preadolescent children. Gender may modify the association between FI and dieting behavior. PUBLIC SIGNIFICANCE STATEMENT: More child-reported food insecurity, but not parent-reported household food insecurity, was associated with more eating disorder risk factors and symptoms among preadolescent boys and girls. These findings emphasize the need for future studies that investigate the role of food insecurity in the development of eating disorders, especially studies that measure child-reported experience of food insecurity.


Subject(s)
Feeding and Eating Disorders , Food Insecurity , Cross-Sectional Studies , Feeding and Eating Disorders/diagnosis , Feeding and Eating Disorders/epidemiology , Female , Humans , Male , Poverty , Risk Factors
3.
ACS Appl Mater Interfaces ; 14(5): 7340-7349, 2022 Feb 09.
Article in English | MEDLINE | ID: mdl-35089024

ABSTRACT

Polymers are commonly used in applications that require long-term exposure to water and aqueous mixtures, serving as water purification membranes, marine antifouling coatings, and medical implants, among many other applications. Because polymer surfaces restructure in response to the surrounding environment, in situ characterization is crucial for providing an accurate understanding of the surface chemistry under conditions of use. To investigate the effects of surface-active side chains on polymer surface chemistry and resultant interactions with interfacial water (i.e., water sorption), we present synchrotron ambient pressure X-ray photoelectron spectroscopy (APXPS) studies performed on poly(ethylene oxide) (PEO)- and poly(dimethylsiloxane) (PDMS)-based polymer surfaces modified with amphiphilic polypeptoid side chains, previously demonstrated to be efficacious in marine fouling prevention and removal. The polymer backbone and environmental conditions were found to affect polypeptoid surface presentation: due to the surface segregation of its fluorinated polypeptoid monomers under vacuum, the PEO-peptoid copolymer showed significant polypeptoid content in both vacuum and hydrated conditions, while the modified PDMS-based copolymer showed increased polypeptoid content only in hydrated conditions due to the hydrophilicity of the ether monomers and polypeptoid backbone. Polypeptoids were found to bind approximately 2.8 water molecules per monomer unit in both copolymers, and the PEO-peptoid surface showed substantial water sorption that suggests a surface with a more diffuse water/polymer interface. This work implies that side chains are ideal for tuning water affinity without altering the base polymer composition, provided that surface-driving groups are present to ensure activity at the interface. These types of systematic modifications will generate novel polymers that maximize bound interfacial water and can deliver surface-active groups to the surface to improve the effectiveness of polymer materials.

4.
Soc Psychiatry Psychiatr Epidemiol ; 57(7): 1483-1490, 2022 Jul.
Article in English | MEDLINE | ID: mdl-34175963

ABSTRACT

PURPOSE: To examine cross-sectional associations between food insecurity and 12-month eating disorders, mood disorders, and anxiety disorders among U.S. adults. METHODS: This study used data collected between 2001 and 2003 from 2914 participants in the National Comorbidity Survey-Replication, a nationally representative sample of U.S. adults (mean age = 44.9 years; 53.4% female). Twelve-month food insecurity was assessed with a modified version of the Short Form U.S. Household Food Security Scale. Twelve-month DSM-IV diagnoses of mental disorders were based on the World Health Organization Composite International Diagnostic Interview. Modified Poisson regression models were conducted, adjusting for age, sex, race/ethnicity, education, and income-to-poverty ratio. RESULTS: Food insecurity was experienced by 11.1% of participants. Food insecurity was associated with greater prevalence of bulimic-spectrum eating disorders (prevalence ratio [PR] = 3.81; 95% confidence interval [CI] 2.26-6.42), mood disorders (PR = 2.53; 95% CI 1.96-3.29), and anxiety disorders (PR = 1.69; 95% CI 1.39-2.07). CONCLUSION: Results indicate that food insecurity is associated with a range of internalizing mental disorders, though these findings should be confirmed with contemporary data to reflect DSM-5 diagnostic updates and the economic effects of the COVID-19 pandemic. Findings from this study emphasize the need to expand food insecurity interventions and improve access to mental health services for food-insecure populations.


Subject(s)
Bulimia , COVID-19 , Feeding and Eating Disorders , Adult , Anxiety Disorders/psychology , Bulimia/epidemiology , Cross-Sectional Studies , Feeding and Eating Disorders/epidemiology , Female , Food Insecurity , Food Supply , Humans , Male , Middle Aged , Mood Disorders/epidemiology , Pandemics
5.
J Acad Nutr Diet ; 121(6): 1115-1124, 2021 06.
Article in English | MEDLINE | ID: mdl-33773946

ABSTRACT

BACKGROUND: College students experience a disproportionately high prevalence of both food insecurity and eating disorders. Food insecurity is associated with stress, irregular eating patterns, weight change, depression, and body dissatisfaction, making it a possible risk factor for the onset of eating disorders. However, the association between food insecurity and eating disorders among college students is not well understood. OBJECTIVE: This study explored the relation between food insecurity and screening positive for an eating disorder among students attending a large, public Midwestern university. DESIGN: Cross-sectional data were collected using an online survey administered from March through June 2018. PARTICIPANTS/SETTING: Participants were recruited from a random sample of 2,000 students, with oversampling from the following groups: racial/ethnic minorities, first-generation students, and students from lower-income households. Of those sampled, 851 students (43%) responded. The final analytic sample comprised 804 students after excluding those with missing data. MAIN OUTCOME MEASURE: The validated 5-item Sick, Control, One stone, Fat, Food (SCOFF) questionnaire was used to screen for the presence of an eating disorder. STATISTICAL ANALYSES PERFORMED: Poisson regression was used to model prevalence ratios for positive SCOFF screens (≥2 affirmative responses) by levels of food security (ie, high, marginal, low, or very low). Models were adjusted for sex, age, race/ethnicity, degree type, financial aid, and first-generation student status. RESULTS: Compared to students with high food security, a higher prevalence of positive SCOFF screens was found among students with marginal food security (prevalence ratio [PR], 1.83, 95% CI 1.26 to 2.65; P = 0.001), low food security (PR 1.72, 95% CI 1.16 to 2.54; P = 0.007), and very low food security (PR 2.83, 95% CI 2.01 to 3.97; P < .0001). CONCLUSIONS: Students with food insecurity at any level were more likely to screen positive for an eating disorder via the SCOFF questionnaire. Prospective studies are needed to determine whether food insecurity is a risk factor for the onset of eating disorders among college students.


Subject(s)
Feeding and Eating Disorders/epidemiology , Food Insecurity , Students/statistics & numerical data , Universities , Cross-Sectional Studies , Feeding and Eating Disorders/diagnosis , Female , Food Security/statistics & numerical data , Humans , Male , Socioeconomic Factors , Surveys and Questionnaires , United States/epidemiology , Young Adult
6.
Eat Weight Disord ; 26(7): 2371-2379, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33389717

ABSTRACT

PURPOSE: To examine the longitudinal associations between parental perceptions of their child's actual weight (PPCA = parental perception of child's actual) and ideal weight (PPCI = parental perception of child ideal) in early childhood and the child's own perceptions of their actual weight (APA = adolescent perceived actual) and ideal weight (API = adolescent perceived ideal) during early adolescence among a low-income population. METHODS: Using a longitudinal study design, 136 child/parent pairs were asked to assess the child's actual and ideal weight using figure rating scales. When children were 4-7 years old, parents reported on their perception of their child's weight; when children were 10-12 years old, the child reported on their own weight perceptions. Actual weight, ideal weight, and the difference between ideal and actual weight perception were assessed at the respective timepoints. Regressions were used to examine the relationship between parental weight perceptions (PPCA and PPCI) and later adolescent weight perception (APA and API). RESULTS: On average, PPCI was higher than PPCA, whereas API was lower than APA. We found a positive relationship between PPCI and API (ß = 0.309, p = .029). PPCA was positively associated with API (ß = 0.304, p = .015) and marginally positively associated with the APA (ß = 0.242, p = .077). However, the difference between PPCI and PPCA did not predict either APA or API. CONCLUSIONS: Parental perception of their child's weight may relate to the adolescent's weight perception, particularly ideal weight. However, several null and marginal associations suggest that parental weight perception in early childhood may not be the most salient factor in determining weight perception in early adolescence. LEVEL OF EVIDENCE: Level III, well-designed longitudinal cohort study.


Subject(s)
Ideal Body Weight , Poverty , Adolescent , Body Mass Index , Body Weight , Child , Child, Preschool , Humans , Longitudinal Studies , Parents , Perception , Surveys and Questionnaires
7.
Public Health Nutr ; 24(6): 1566-1569, 2021 04.
Article in English | MEDLINE | ID: mdl-33168123

ABSTRACT

OBJECTIVE: To explore explicit beliefs about the controllability of obesity and the internalisation of negative weight-related stereotypes among public health trainees. DESIGN: Cross-sectional online survey assessing explicit beliefs about the controllability of obesity using the Beliefs About Obese Persons Scale (BAOP) and internalisation of weight bias using the Modified Weight Bias Internalization Scale (WBIS-M). Bivariate associations between BAOP and WBIS-M scores and demographic characteristics were examined using t tests or ANOVA with post hoc Tukey's tests. SETTING: School of Public Health at a large, Midwestern University. PARTICIPANTS: Public health students (n 322). RESULTS: Relative to students who identified as male, those who identified as female had a stronger belief that obesity is not within the control of the individual (P = 0·03), yet had more internalisation of weight bias (P < 0·01). Greater weight bias internalisation was also seen among students who perceived themselves to be of a higher weight status (P < 0·001) and those who were at risk for food insecurity (P < 0·01). CONCLUSIONS: Public health trainees may be more attuned to the complexities of weight relative to trainees in other health-related fields, but are still susceptible to internalisation of negative weight-related stereotypes.


Subject(s)
Overweight , Public Health , Bias , Cross-Sectional Studies , Female , Humans , Male , Obesity/epidemiology , Surveys and Questionnaires
8.
J Am Chem Soc ; 142(46): 19631-19641, 2020 11 18.
Article in English | MEDLINE | ID: mdl-33141567

ABSTRACT

We introduce a powerful, widely applicable approach to characterizing polymer conformational distributions, specifically the end-to-end distance distributions, P(Ree), accessed through double electron-electron resonance (DEER) spectroscopy in conjunction with molecular dynamics (MD) simulations. The technique is demonstrated on one of the most widely used synthetic, disordered, water-soluble polymers: poly(ethylene oxide) (PEO). Despite its widespread importance, no systematic experimental characterization of PEO's Ree conformational landscape exists. The evaluation of P(Ree) is particularly important for short polymers or (bio)polymers with sequence complexities that deviate from simple polymer physics scaling laws valid for long chains. In this study, we characterize the Ree landscape by measuring P(Ree) for low molecular weight (MW: 0.22-2.6 kDa) dilute PEO chains. We use DEER with end-conjugated spin probes to resolve Ree populations from ∼2-9 nm and compare them with full distributions from MD. The P( Ree)'s from DEER and MD show remarkably good agreement, particularly at longer chain lengths where populations in the DEER-unresolvable range (<1.5 nm) are low. Both the P(Ree) and the root-mean-square R̃ee indicate that aqueous PEO is a semiflexible polymer in a good solvent, with the latter scaling linearly with molecular weight up to its persistence length (lp ∼ 0.48 nm), and rapidly transitioning to excluded volume scaling above lp. The R̃ee scaling is quantitatively consistent with that from experimental scattering data on high MW (>10 kDa) PEO and the P(Ree)'s crossover to the theoretical distribution for an excluded volume chain.

9.
Annu Rev Chem Biomol Eng ; 11: 523-557, 2020 06 07.
Article in English | MEDLINE | ID: mdl-32169001

ABSTRACT

The properties of water on both molecular and macroscopic surfaces critically influence a wide range of physical behaviors, with applications spanning from membrane science to catalysis to protein engineering. Yet, our current understanding of water interfacing molecular and material surfaces is incomplete, in part because measurement of water structure and molecular-scale properties challenges even the most advanced experimental characterization techniques and computational approaches. This review highlights progress in the ongoing development of tools working to answer fundamental questions on the principles that govern the interactions between water and surfaces. One outstanding and critical question is what universal molecular signatures capture the hydrophobicity of different surfaces in an operationally meaningful way, since traditional macroscopic hydrophobicity measures like contact angles fail to capture even basic properties of molecular or extended surfaces with any heterogeneity at the nanometer length scale. Resolving this grand challenge will require close interactions between state-of-the-art experiments, simulations, and theory, spanning research groups and using agreed-upon model systems, to synthesize an integrated knowledge of solvation water structure, dynamics, and thermodynamics.


Subject(s)
Water/chemistry , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Magnetic Resonance Spectroscopy , Solvents/chemistry , Spectrophotometry , Surface Properties , Thermodynamics
10.
ACS Biomater Sci Eng ; 6(4): 2029-2037, 2020 04 13.
Article in English | MEDLINE | ID: mdl-33455354

ABSTRACT

The antifouling properties of poly(ethylene oxide) (PEO)-silane amphiphiles as surface-modifying additives (SMAs) in a condensation cure silicone have been previously demonstrated against simple protein solutions. Comprising an oligo(dimethylsiloxane) tether (m = 13 or 30) and PEO segment (n = 8), sustained protein resistance was achieved even in the absence of a cross-linkable triethoxysilane group, particularly when comprising the longer tether. To probe their potential for thromboresistance, PEO-silane amphiphile SMAs were used to bulk-modify silicones and evaluated for adhesion resistance against whole human blood under both static and dynamic conditions. Both a cross-linkable (XL diblock, m = 13) and a non-cross-linkable (Diblock, m = 30) SMA were evaluated at various concentrations (5-50 µmol SMA/g silicone) in a condensation cure silicone. Under static conditions, silicones modified with either SMA at concentrations of 10 µmol/g or greater were effective in reducing adhesion of human fibrinogen and platelets. Dynamic testing further showed that modified silicones were able to reduce protein adsorption and thrombus formation. This occurred at 5 and 10 µmol/g for silicones modified with XL diblock, m = 13 and Diblock, m = 30 SMAs, respectively. Combined, these results indicate the effectiveness of PEO-silane amphiphiles as SMAs in silicone for improved thromboresistance.


Subject(s)
Silanes , Silicones , Adsorption , Humans , Polyethylene Glycols , Surface Properties
11.
Appetite ; 147: 104560, 2020 04 01.
Article in English | MEDLINE | ID: mdl-31870936

ABSTRACT

OBJECTIVE: To examine associations between psychological stress and dieting behavior along with the heterogeneity of this association by gender and race in a diverse sample of adolescents with overweight/obesity. METHODS: One hundred and sixty-one adolescents between the ages of 13-19 years of age with overweight/obesity (65% female; 53% non-Hispanic black/47% non-Hispanic white; age: 16.7 ± 1.7 years) were recruited from Southeast MI and included in this analysis. Psychological stress was measured using the Perceived Stress Scale, and dieting behavior was assessed using the dieting subscale from the Eating Attitudes Test (EAT-26) questionnaire. Multivariable linear regression models were conducted to examine the association between psychological stress and dieting behavior by gender and race. RESULTS: Psychological stress was significantly associated with dieting (ß = 0.18 ± 0.06; p < 0.01), with greater stress associated with greater frequency of dieting behavior. This relationship remained significant (ß = 0.15 ± 0.06; p = 0.016), even when controlling for covariates (age, body fat, gender, race, and pubertal development). There were no statistically significant differences in the association of psychological stress and disordered eating indices by gender or race/ethnicity (p's > 0.05). CONCLUSIONS: Increased psychological stress is associated with increased dieting behavior among adolescents with overweight/obesity. These findings suggest that psychological stress equally affects dieting behavior among adolescents with overweight/obesity, regardless of gender and race. Future studies should seek to identify the unique sources of psychological stress that contribute to increased dieting behavior among adolescents with overweight/obesity.


Subject(s)
Adolescent Behavior/psychology , Diet, Reducing/psychology , Feeding Behavior/psychology , Pediatric Obesity/psychology , Stress, Psychological/psychology , Adolescent , Adolescent Behavior/ethnology , Black People/psychology , Diet, Reducing/ethnology , Feeding Behavior/ethnology , Female , Humans , Linear Models , Male , Michigan , Pediatric Obesity/ethnology , Racial Groups/psychology , Sex Factors , Stress, Psychological/ethnology , Surveys and Questionnaires , Young Adult
12.
J Acad Nutr Diet ; 119(10): 1623-1631, 2019 10.
Article in English | MEDLINE | ID: mdl-31561811

ABSTRACT

BACKGROUND: Food insecurity is a growing issue of concern on college campuses. While many studies have focused on predictors of food insecurity, fewer studies have examined how food insecurity affects diet and diet-related outcomes among college students. OBJECTIVE: The objective of this study was to examine differences in dietary intake, food and cooking agency, and body mass index (calculated as kg/m2) by food security status in a sample of college students at a large, public midwestern university. DESIGN: We conducted a cross-sectional online survey administered from March to June 2018. PARTICIPANTS: Students were recruited from a random sample (n=2,000) provided by the university, which included an oversample of minority racial/ethnic students from lower-income households and first-generation students. The response rate was 43% (n=851). After excluding students with missing data, the final sample was 754 enrolled students. MAIN OUTCOME MEASURES: Food security status was measured using the US Adult Food Security Survey Module. Dietary intake was assessed using the National Cancer Institute dietary screener questionnaire. Cooking and food agency was measured using the Cooking and Food Provisioning Action Scale, a new validated questionnaire. Body mass index was calculated from self-reported height and weight. STATISTICAL ANALYSIS PERFORMED: Differences between food security categories and diet-related outcomes were examined using generalized linear models. Models adjusted for sociodemographic covariates, such as student's age, sex, race/ethnicity, and receipt of financial aid. RESULTS: Compared to students with high food security, low food security was associated with lower intake of fruits, and very low food security was associated with higher intakes of total added sugar and added sugar from sugar-sweetened beverages. Marginal and very low food security were positively associated with body mass index. Marginal, low, and very low food security were inversely associated with cooking and food agency. CONCLUSIONS: Students with food insecurity experience diet-related challenges that could translate into health disparities over time. More research is needed to understand the longitudinal effects of food insecurity on student health and well being.


Subject(s)
Diet/statistics & numerical data , Food Supply/statistics & numerical data , Health Status , Students/statistics & numerical data , Adult , Body Mass Index , Cross-Sectional Studies , Diet/adverse effects , Diet Surveys , Female , Health Status Disparities , Humans , Linear Models , Male , Midwestern United States , Universities , Young Adult
13.
Biofouling ; 34(7): 769-783, 2018 08.
Article in English | MEDLINE | ID: mdl-30332896

ABSTRACT

Pasteurization of dairy products is plagued by fouling, which induces significant economic, environmental and microbiological safety concerns. Herein, an amphiphilic silicone coating was evaluated for its efficacy against fouling by a model dairy fluid in a pilot pasteurizer and against foodborne bacterial adhesion. The coating was formed by modifying an RTV silicone with a PEO-silane amphiphile comprised of a PEO segment and flexible siloxane tether ([(EtO)3Si-(CH2)2-oligodimethylsiloxanem-block-(OCH2CH2)n-OCH3]). Contact angle analysis of the coating revealed that the PEO segments were able to migrate to the aqueous interface. The PEO-modified silicone coating applied to pretreated stainless steel was exceptionally resistant to fouling. After five cycles of pasteurization, these coated substrata were subjected to a standard clean-in-place process and exhibited a minor reduction in fouling resistance in subsequent tests. However, the lack of fouling prior to cleaning indicates that harsh cleaning is not necessary. PEO-modified silicone coatings also showed exceptional resistance to adhesion by foodborne pathogenic bacteria.


Subject(s)
Biofouling/prevention & control , Dairying/standards , Pasteurization/standards , Silicones/chemistry , Stainless Steel/chemistry , Surface-Active Agents/chemistry , Bacterial Adhesion , Biofilms/growth & development , Silanes/chemistry , Siloxanes/chemistry , Surface Properties
14.
Green Mater ; 5(1): 4-13, 2017 Mar.
Article in English | MEDLINE | ID: mdl-31673356

ABSTRACT

Surface modifying additives (SMAs), which may be readily blended into silicones to improve anti-fouling behavior, must have excellent surface migration potential and must not leach into the aqueous environment. In this work, we evaluated the efficacy of a series of poly(ethylene oxide) (PEO)-based SMA amphiphiles which varied in terms of crosslinkability, siloxane tether length (m) and diblock versus triblock architectures. Specifically, crosslinkable, diblock PEO-silane amphiphiles with two oligodimethylsiloxane (ODMS) tether lengths [(EtO)3Si-(CH2)3-ODMS m -PEO8, m = 13 and 30] were compared to analogous non-crosslinkable, diblock (H-Si-ODMS m -PEO8) and triblock (PEO8-ODMS m -PEO8) SMAs. Prior to water conditioning, while all modified silicone coatings exhibited a high degree of water-driven surface restructuring, that prepared with the non-crosslinkable diblock SMA (m = 13) was the most hydrophilic. After conditioning, all modified silicone coatings were similarly hydrophilic and remained highly protein resistant, with the exception of PEO8-ODMS 30 -PEO8. Notably, despite twice the PEO content, triblock SMAs were not superior to diblock SMAs. For diblock SMAs, it was shown that water uptake and leaching were also similar whether or not the SMA was crosslinkable.

15.
Curr Osteoporos Rep ; 14(3): 87-94, 2016 06.
Article in English | MEDLINE | ID: mdl-27048473

ABSTRACT

Osteoporosis is a degenerative bone disease commonly related to aging. With an increase in life expectancies worldwide, the prevalence of the disease is expected to rise. Current clinical therapeutic treatments are not able to offer long-term solutions to counter the bone mass loss and the increased risk of fractures, which are the primary characteristics of the disease. However, the combination of bioactive nanomaterials within a biomaterial scaffold shows promise for the development of a localized, long-term treatment for those affected by osteoporosis. This review summarizes the unique characteristics of engineered nanoparticles that render them applicable for bone regeneration and recaps the current body of knowledge on nanomaterials with potential for osteoporosis treatment and bone regeneration. Specifically, we highlight new developments that are shaping this emerging field and evaluate applications of recently developed nanomaterials for osteoporosis treatment. Finally, we will identify promising new research directions in nanotechnology for bone regeneration.


Subject(s)
Bone Morphogenetic Protein 2/administration & dosage , Bone Regeneration , Estrogens/administration & dosage , Fractures, Bone/prevention & control , Nanostructures/therapeutic use , Osteoporosis/therapy , Biocompatible Materials , Bone Density , Bone Remodeling , Drug Delivery Systems , Humans , Nanotechnology , Tissue Engineering
16.
Acta Biomater ; 41: 247-52, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27090588

ABSTRACT

UNLABELLED: In contrast to modification with conventional PEO-silanes (i.e. no siloxane tether), silicones with dramatically enhanced protein resistance have been previously achieved via bulk-modification with poly(ethylene oxide) (PEO)-silane amphiphiles α-(EtO)3Si(CH2)2-oligodimethylsiloxane13-block-PEOn-OCH3 when n=8 and 16 but not when n=3. In this work, their efficacy was evaluated in terms of optimal PEO-segment length and minimum concentration required in silicone. For each PEO-silane amphiphile (n=3, 8, and 16), five concentrations (5, 10, 25, 50, and 100µmol per 1g silicone) were evaluated. Efficacy was quantified in terms of the modified silicones' abilities to undergo rapid, water-driven surface restructuring to form hydrophilic surfaces as well as resistance to fibrinogen adsorption. Only n=8 and 16 were effective, with a lower minimum concentration in silicone required for n=8 (10µmol per 1g silicone) versus n=16 (25µmol per 1g silicone). STATEMENT OF SIGNIFICANCE: Silicone is commonly used for implantable medical devices, but its hydrophobic surface promotes protein adsorption which leads to thrombosis and infection. Typical methods to incorporate poly(ethylene oxide) (PEO) into silicones have not been effective due to the poor migration of PEO to the surface-biological interface. In this work, PEO-silane amphiphiles - comprised of a siloxane tether (m=13) and variable PEO segment lengths (n=3, 8, 16) - were blended into silicone to improve its protein resistance. The efficacy of the amphiphiles was determined to be dependent on PEO length. With the intermediate PEO length (n=8), water-driven surface restructuring and resulting protein resistance was achieved with a concentration of only 1.7wt%.


Subject(s)
Fibrinogen/chemistry , Polyethylene Glycols/chemistry , Silanes/chemistry , Surface-Active Agents/chemistry , Adsorption , Humans , Silicones/chemistry , Surface Properties , Water/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...