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1.
Biomacromolecules ; 23(6): 2388-2395, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35512280

RESUMO

Additive manufacturing is rapidly advancing tissue engineering, but the scope of its clinical translation is limited by a lack of materials designed to meet specific mechanical properties and resorption timelines. Materials that are printable via photochemical cross-linking, fully degradable, and elastomeric have proven to be particularly challenging to develop. Herein, we report the synthesis of a series of poly(propylene fumarate-b-γ-methyl-ε-caprolactone-b-propylene fumarate) ABA triblock polymers using sequential ring-opening polymerization and ring-opening copolymerization. When cross-linked photochemically using a continuous liquid interface production digital light processing Carbon M2 printer, these ABA-type triblock copolymers are durable elastomers with tunable degradation and elastic properties. The polymers are shown to undergo slow, hydrolytic degradation in vitro with minimal loss of mechanical performance during degradation.


Assuntos
Materiais Biocompatíveis , Elastômeros , Materiais Biocompatíveis/química , Elastômeros/química , Fumaratos , Polímeros/química , Polipropilenos
2.
J Clin Psychol ; 77(4): 1045-1053, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33296527

RESUMO

OBJECTIVES: There is a dearth of research on suicidal thoughts and behaviors among eating disorder patients diagnosed with binge eating disorder (BED) or other specified feeding or eating disorder (OSFED). This pilot study evaluated presence and severity of suicidal thoughts and behaviors by eating disorder diagnosis in a transdiagnostic clinical eating disorder sample. METHODS: Participants were individuals (N = 257; 91.1% female; 94.6% Caucasian) currently receiving eating disorder treatment for anorexia nervosa (AN), bulimia nervosa (BN), BED, or OSFED. Participants completed online measures of variables. RESULTS: Lifetime and current presence and severity of suicidal ideation and suicide attempts were statistically similar among diagnostic groups. CONCLUSION: Though largely overlooked, treatment-utilizing individuals with BED and OSFED may experience elevated rates and severity of suicidal thoughts and behaviors, like those with AN and BN. Attention to suicide-related risk assessment and management is needed when treating individuals with eating disorders, regardless of diagnosis.


Assuntos
Anorexia Nervosa , Transtorno da Compulsão Alimentar , Bulimia Nervosa , Transtornos da Alimentação e da Ingestão de Alimentos , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Feminino , Humanos , Masculino , Projetos Piloto , Ideação Suicida
3.
Int J Eat Disord ; 53(10): 1746-1750, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33464582

RESUMO

OBJECTIVE: Research has established pairwise relationships between suicidal ideation (SI), low Body Trust, elevated agitation, and eating disorders, but knowledge of how these aspects relate in a single model is lacking. This study tested an indirect pathway with low Body Trust relating to severity of SI via agitation in a clinical eating disorder sample. METHOD: Participants (N = 319; 92.8% female; 93.4% Caucasian; mean age 21.8 years) were adults currently receiving specialized eating disorder treatment (44.3% intensive outpatient or higher level-of-care) who completed online self-report measures of study variables. The PROCESS macro was utilized to test proposed pathways. RESULTS: Low Body Trust was significantly directly associated with increased severity of current SI, both before (B = -.89, p < .001) and after (B = -.51, p = .001) accounting for the indirect effect through agitation, also significant (B = -.37, SE = .06, CI -.52 to -.26). DISCUSSION: Perception of the body as unsafe may be related to agitation, and this intolerable sensation of trapped arousal could contribute to a desire to die. Future work should investigate these relationships prospectively to determine the relevance of Body Trust for assessment and treatment of suicide-related factors among individuals with eating disorders.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Agitação Psicomotora/psicologia , Ideação Suicida , Adulto , Transtornos da Alimentação e da Ingestão de Alimentos/mortalidade , Feminino , Humanos , Masculino , Autorrelato , Análise de Sobrevida , Confiança , Adulto Jovem
4.
Langmuir ; 35(29): 9572-9583, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31240935

RESUMO

Block copolymer templating enables the generation of well-defined pore sizes and geometries in a wide variety of frameworks, typically through evaporation-induced self-assembly (EISA). Here, we systematically modulate the solvent quality with mixtures of tetrahydrofuran-ethanol (THF-EtOH) to manipulate the unimer/micelle ratio in the precursor solution to explore how the associated solution structure influences the final pore morphology. A bottlebrush block copolymer (BBCP) with poly(ethylene oxide) and poly(t-butyl acrylate) side chains was used as the template for pore formation. Irrespective of the solvent composition, a bimodal pore size distribution was obtained with mesopores templated by small aggregates of the BBCP unimers (potentially low aggregation number micelles) and macropores templated by large self-assembled BBCP micelles. The morphology and pore characteristics of the metal oxide films were dependent on the THF-EtOH composition. Interestingly, an intermediate solvent composition where the volume of micelles is approximately half the volume of unimers (in the precursor solution) leads to the best ordering of micelle-templated pores and also the maximum porosity in the films. The micelle/unimer ratios in the precursor solutions do not correspond directly to the bimodal pore distribution in the metal oxide films, which we attribute to kinetically trapped assembly of the BBCP at a low THF content. The increased critical micelle concentration at high THF composition leads to changes in the unimer/micelle ratio during solvent evaporation. These results appear to be universal for a number of metal oxides (cobalt, magnesium, and zinc) with the porosity maximized at a THF/EtOH ratio of 3:1. These results suggest the potential for enhancements in the porosity of block copolymer-templated films by EISA methods through judicious solvent selection.

5.
Annu Rev Chem Biomol Eng ; 14: 109-140, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37040783

RESUMO

Alternative polymer feedstocks are highly desirable to address environmental, social, and security concerns associated with petrochemical-based materials. Lignocellulosic biomass (LCB) has emerged as one critical feedstock in this regard because it is an abundant and ubiquitous renewable resource. LCB can be deconstructed to generate valuable fuels, chemicals, and small molecules/oligomers that are amenable to modification and polymerization. However, the diversity of LCB complicates the evaluation of biorefinery concepts in areas including process scale-up, production outputs, plant economics, and life-cycle management. We discuss aspects of current LCB biorefinery research with a focus on the major process stages, including feedstock selection, fractionation/deconstruction, and characterization, along with product purification, functionalization, and polymerization to manufacture valuable macromolecular materials. We highlight opportunities to valorize underutilized and complex feedstocks, leverage advanced characterization techniques to predict and manage biorefinery outputs, and increase the fraction of biomass converted into valuable products.


Assuntos
Lignina , Polímeros , Lignina/química , Plantas , Engenharia , Biomassa , Biocombustíveis
6.
Artigo em Inglês | MEDLINE | ID: mdl-35052020

RESUMO

Objective: Recent evidence suggests psychosocial stressors stemming from coronavirus disease 2019 (COVID-19) exposure and public health recommendations and policies have exacerbated eating disorder symptoms. Consequentially, eating disorder acuity has increased during the COVID-19 pandemic. Currently, it is still unclear how the COVID-19 pandemic may be impacting individuals receiving treatment for eating disorders at higher levels of care. The purpose of this study was to examine the impact of COVID-19 on eating disorder symptoms and associated outcomes in a sample of individuals receiving eating disorder treatment compared to individuals receiving treatment in 2019.Methods: Blinded outcomes data from 272 adults who completed treatment at an eating disorder treatment center between April and October of 2019 (pre-COVID-19 group) and 2020 (COVID-19 group) were examined. Repeated measures analyses of variance with Bonferroni correction were used to examine differences in outcome variables and treatment response.Results: Fewer participants reported trauma in 2020, but symptoms were more severe when present. A significant interaction effect for treatment (eg, admission, discharge) and year (eg, pre-COVID-19, COVID-19) was found for eating disorder and trauma symptoms. Moreover, trauma symptom scores were higher in 2020 than in 2019. The interaction among year, trauma, and treatment was significant (F3,268 = 2.11, P = .027, η2 = 0.034), indicating that individuals with severe trauma in 2020 reported less eating disorder symptom score reduction.Conclusions: Results extend understanding of effects during the COVID-19 pandemic on treatment-seeking individuals with eating disorders. Clinical implications suggest that greater attention to trauma when screening eating disorder patients and selecting treatment approaches are needed, particularly during the COVID-19 pandemic.


Assuntos
COVID-19 , Transtornos da Alimentação e da Ingestão de Alimentos , Adulto , Comorbidade , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/terapia , Humanos , Pandemias , SARS-CoV-2
7.
Sci Rep ; 7: 43418, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266537

RESUMO

The self-assembly of lipid bilayer membranes to enclose functional biomolecules, thus defining a "protocell," was a seminal moment in the emergence of life on Earth and likely occurred at the micro-environment of the mineral-water interface. Mineral-lipid interactions are also relevant in biomedical, industrial and technological processes. Yet, no structure-activity relationships (SARs) have been identified to predict lipid self-assembly at mineral surfaces. Here we examined the influence of minerals on the self-assembly and survival of vesicles composed of single chain amphiphiles as model protocell membranes. The apparent critical vesicle concentration (CVC) increased in the presence of positively-charged nanoparticulate minerals at high loadings (mg/mL) suggesting unfavorable membrane self-assembly in such situations. Above the CVC, initial vesicle formation rates were faster in the presence of minerals. Rates were correlated with the mineral's isoelectric point (IEP) and reactive surface area. The IEP depends on the crystal structure, chemical composition and surface hydration. Thus, membrane self-assembly showed rational dependence on fundamental mineral properties. Once formed, membrane permeability (integrity) was unaffected by minerals. Suggesting that, protocells could have survived on rock surfaces. These SARs may help predict the formation and survival of protocell membranes on early Earth and other rocky planets, and amphiphile-mineral interactions in diverse other phenomena.

8.
Autoimmun Rev ; 13(4-5): 560-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24418298

RESUMO

Uncompensated autoantibody-mediated red blood cell (RBC) consumption is the hallmark of autoimmune hemolytic anemia (AIHA). Classification of AIHA is pathophysiologically based and divides AIHA into warm, mixed or cold-reactive subtypes. This thermal-based classification is based on the optimal autoantibody-RBC reactivity temperatures. AIHA is further subcategorized into idiopathic and secondary with the later being associated with a number of underlying infectious, neoplastic and autoimmune disorders. In most cases AIHA is confirmed by a positive direct antiglobulin test (DAT). The standard therapeutic approaches to treatment of AIHA include corticosteroids, splenectomy, immunosuppressive agents and monoclonal antibodies.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Corticosteroides/uso terapêutico , Anemia Hemolítica Autoimune/induzido quimicamente , Anemia Hemolítica Autoimune/tratamento farmacológico , Anemia Hemolítica Autoimune/imunologia , Anticorpos Monoclonais/uso terapêutico , Teste de Coombs , Humanos , Imunossupressores/uso terapêutico , Esplenectomia
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