Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Database
Language
Publication year range
1.
Plants (Basel) ; 12(6)2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36986914

ABSTRACT

Efficient determination of antioxidant activity in medicinal plants may provide added value to extracts. The effects of postharvest pre-freezing and drying [microwave-assisted hot air (MAHD) and freeze drying] on hops and cannabis were evaluated to determine the relationship between antioxidant activity and secondary metabolites. The 2,2-diphenyl-1-picrylhydrazine (DPPH) reduction and ferric reducing ability of power (FRAP) assays were assessed for suitability in estimating the antioxidant activity of extracted hops and cannabis inflorescences and correlation with cannabinoid and terpene content. Antioxidant activity in extracts obtained from fresh, undried samples amounted to 3.6 Trolox equivalent antioxidant activity (TEAC) (M) dry matter-1 and 2.32 FRAP (M) dry matter-1 for hops, in addition to 2.29 TEAC (M) dry matter-1 and 0.25 FRAP (M) dry matter-1 for cannabis. Pre-freezing significantly increased antioxidant values by 13% (DPPH) and 29.9% (FRAP) for hops, and by 7.7% (DPPH) and 19.4% (FRAP) for cannabis. ANOVA analyses showed a significant (p < 0.05) increase in total THC (24.2) and THCA (27.2) concentrations (g 100 g dry matter-1) in pre-frozen, undried samples compared to fresh, undried samples. Freeze-drying and MAHD significantly (p < 0.05) reduced antioxidant activity in hops by 79% and 80.2% [DPPH], respectively and 70.1% and 70.4% [FRAP], respectively, when compared to antioxidant activity in extracts obtained from pre-frozen, undried hops. DPPH assay showed that both freeze-drying and MAHD significantly (p < 0.05) reduced the antioxidant activity of cannabis by 60.5% compared to the pre-frozen samples although, there was no significant (p < 0.05) reduction in the antioxidant activity using the FRAP method. Greater THC content was measured in MAHD-samples when compared to fresh, undried (64.7%) and pre-frozen, undried (57%), likely because of decarboxylation. Both drying systems showed a significant loss in total terpene concentration, yet freeze-drying has a higher metabolite retention compared to MAHD. These results may prove useful for future experiments investigating antioxidant activity and added value to cannabis and hops.

2.
Med Educ ; 57(6): 523-534, 2023 06.
Article in English | MEDLINE | ID: mdl-36456473

ABSTRACT

OBJECTIVE: The objective of this study is to investigate whether self-disclosed disability and self-reported program access are associated with measures of empathy and burnout in a national sample of US medical students. METHODS: The authors obtained data from students who responded to the Association of Medical Colleges (AAMC) Year 2 Questionnaire (Y2Q) in 2019 and 2020. Data included demographic characteristics, personal variables, learning environment indicators, measures of burnout (Oldenburg Burnout Inventory for Medical Students), empathy (Interpersonal Reactivity Index) and disability-related questions, including self-reported disability, disability category and program access. Associations between disability status, program access, empathy and burnout were assessed using multivariable logistic regression models accounting for YQ2 demographic, personal-related and learning environment measures. RESULTS: Overall, 23 898 (54.2%) provided disability data and were included. Of those, 2438 (10.2%) self-reported a disability. Most medical students with disabilities (SWD) self-reported having program access through accommodations (1215 [49.8%]) or that accommodations were not required for access (824 [33.8%]). Multivariable models identified that compared with students without disabilities, SWD with and without program access presented higher odds of high exhaustion (1.50 [95% CI, 1.34-1.69] and 2.59 [95% CI, 1.93-3.49], respectively) and lower odds of low empathy (0.75 [95% CI, 0.67-.85] and 0.68 [95% CI, 0.52-0.90], respectively). In contrast, multivariable models for disengagement identified that SWD reporting lack of program access presented higher odds of high disengagement compared to students without disabilities (1.43 [95% CI, 1.09-1.87], whereas SWD with program access did not (1.09 [95% CI, 0.97-1.22]). CONCLUSIONS: Despite higher odds of high exhaustion, SWD were less likely to present low empathy regardless of program access, and SWD with program access did not differ from students without disabilities in terms of disengagement. These findings add to our understanding of the characteristics and experiences of SWD including their contributions as empathic future physicians.


Subject(s)
Burnout, Professional , Students, Medical , Humans , Empathy , Burnout, Psychological , Burnout, Professional/epidemiology , Surveys and Questionnaires
3.
J Med Educ Curric Dev ; 7: 2382120520965249, 2020.
Article in English | MEDLINE | ID: mdl-33178890

ABSTRACT

BACKGROUND: This study aimed to evaluate and report the national prevalence of disability across undergraduate medical education (UME) and examine differences in the category of disability, and accommodation practices between allopathic (MD)- and osteopathic (DO)-granting programs. METHODS: Between May 20 and June 30, 2020, 75% of institutional representatives at eligible DO schools responded to a web-based survey. The survey assessed the aggregate prevalence of disabled DO students, prevalence of DO students by category of disability, and prevalence of accommodations granted. Descriptive statistics were used to summarize results. Using 2019 MD data, comparisons were made between MD and DO programs to calculate overall prevalence and differences in accommodation practices across undergraduate medical education. RESULTS: DO-granting programs reported a disability prevalence of 4.27% of the total enrollment. Attention-deficit/hyperactivity disorder (ADHD), psychological disabilities, and chronic health disabilities were reported most frequently. DO-granting programs reported higher rates of ADHD than the MD-granting program. The national pooled prevalence of disability across MD- and DO-granting programs was 4.52%. MD-granting programs reported a higher number of students with disabilities and higher rates of psychological disabilities when compared with DO-granting programs. One hundred percent of DO students disclosing disability received some form of accommodation. General clinical accommodations were more frequently provided in MD-granting programs when compared to DO-granting programs. CONCLUSIONS: This study provides the first comprehensive prevalence of US medical student disability and accommodations. Additionally, these data may serve as a benchmark for DO programs, with implications for curricular development, instructional planning and disability support, and resource allocation in medical education.

4.
J Grad Med Educ ; 12(5): 615-619, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33149832

ABSTRACT

BACKGROUND: Graduate medical education (GME) institutions must ensure equal access for trainees with disabilities through appropriate and reasonable accommodations and policies. To date, no comprehensive review of the availability and inclusiveness of GME policies for residents with disabilities exists. OBJECTIVE: We examined institutions' compliance with Accreditation Council for Graduate Medical Education (ACGME) requirements and alignment with Association of American Medical Colleges (AAMC) policy considerations. METHODS: Between June and August 2019, we conducted a directed content analysis of GME institutional policies using the AAMC report on disability considerations and the ACGME institutional requirements as a framework. RESULTS: Of the 47 GME handbooks available for review, 32 (68%) included a disability policy. Forty-one of the 47 (87%) handbooks maintained a nondiscrimination statement that included disability. Twelve of the 32 (38%) handbooks included a specific disability policy and language that encouraged disclosure, and 17 (53%) included a statement about the confidential documentation used to determine reasonable accommodations. Nineteen of the 32 (59%) maintained a clear procedure for disclosing disabilities and requesting accommodations. CONCLUSIONS: While disability policies are present in many of the largest GME institutions, it is not yet a standardized practice. For institutions maintaining a disability policy, many lack key elements identified as best practices in the AAMC considerations.


Subject(s)
Disabled Persons , Education, Medical, Graduate/standards , Internship and Residency/standards , Disclosure , Organizational Policy
6.
Biomaterials ; 52: 71-8, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25818414

ABSTRACT

Delivery of small molecules and drugs to tissues is a mainstay of several tissue engineering strategies. Next generation treatments focused on localized drug delivery offer a more effective means in dealing with refractory healing when compared to systemic approaches. Here we describe a novel multidomain peptide hydrogel that capitalizes on synthetic peptide chemistry, supramolecular self-assembly and cytokine delivery to tailor biological responses. This material is biomimetic, shows shear stress recovery and offers a nanofibrous matrix that sequesters cytokines. The biphasic pattern of cytokine release results in the spatio-temporal activation of THP-1 monocytes and macrophages. Furthermore, macrophage-material interactions are promoted without generation of a proinflammatory environment. Subcutaneous implantation of injectable scaffolds showed a marked increase in macrophage infiltration and polarization dictated by cytokine loading as early as 3 days, with complete scaffold resorption by day 14. Macrophage interaction and response to the peptide composite facilitated the (i) recruitment of monocytes/macrophages, (ii) sustained residence of immune cells until degradation, and (iii) promotion of a pro-resolution M2 environment. Our results suggest the potential use of this injectable cytokine loaded hydrogel scaffold in a variety of tissue engineering applications.


Subject(s)
Cytokines/administration & dosage , Drug Delivery Systems , Macrophages/drug effects , Peptides/chemistry , Tissue Scaffolds/chemistry , Amino Acid Sequence , Animals , Cell Line , Cytokines/immunology , Cytokines/pharmacology , Female , Humans , Macrophages/immunology , Models, Molecular , Molecular Sequence Data , Nanofibers/chemistry , Nanofibers/ultrastructure , Rats, Wistar
7.
ACS Nano ; 9(1): 860-8, 2015 Jan 27.
Article in English | MEDLINE | ID: mdl-25584521

ABSTRACT

Major limitations of current tissue regeneration approaches using artificial scaffolds are fibrous encapsulation, lack of host cellular infiltration, unwanted immune responses, surface degradation preceding biointegration, and artificial degradation byproducts. Specifically, for scaffolds larger than 200-500 µm, implants must be accompanied by host angiogenesis in order to provide adequate nutrient/waste exchange in the newly forming tissue. In the current work, we design a peptide-based self-assembling nanofibrous hydrogel containing cell-mediated degradation and proangiogenic moieties that specifically address these challenges. This hydrogel can be easily delivered by syringe, is rapidly infiltrated by cells of hematopoietic and mesenchymal origin, and rapidly forms an extremely robust mature vascular network. Scaffolds show no signs of fibrous encapsulation and after 3 weeks are resorbed into the native tissue. These supramolecular assemblies may prove a vital paradigm for tissue regeneration and specifically for ischemic tissue disease.


Subject(s)
Angiogenesis Inducing Agents/chemistry , Angiogenesis Inducing Agents/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Nanofibers , Peptides/chemistry , Peptides/pharmacology , Amino Acid Sequence , Animals , Drug Design , Female , Hydrogels/chemistry , Ischemia/pathology , Ischemia/physiopathology , Models, Molecular , Molecular Sequence Data , Protein Conformation , Rats , Rats, Wistar , Tissue Scaffolds/chemistry
8.
Biomacromolecules ; 15(4): 1484-90, 2014 Apr 14.
Article in English | MEDLINE | ID: mdl-24694012

ABSTRACT

Collagen is a major component of the extracellular matrix and plays a wide variety of important roles in blood clotting, healing, and tissue remodeling. Natural, animal derived, collagen is used in many clinical applications but concerns exist with respect to its role in inflammation, batch-to-batch variability, and possible disease transfection. Therefore, development of synthetic nanomaterials that can mimic the nanostructure and properties of natural collagen has been a heavily pursued goal in biomaterials. Previously, we reported on the design and multihierarchial self-assembly of a 36 amino acid collagen mimetic peptide (KOD) that forms nanofibrous triple helices that entangle to form a hydrogel. In this report, we utilize this nanofiber forming collagen mimetic peptide as a synthetic biomimetic matrix useful in thrombosis. We demonstrate that nanofibrous KOD synthetic collagen matrices adhere platelets, activate them (indicated by soluble P-selectin secretion), and clot plasma and blood similar to animal derived collagen and control surfaces. In addition to the thrombotic potential, THP-1 monocytes incubated with our KOD collagen mimetic showed minimal proinflammatory cytokine (TNF-α or IL-1ß) production. Together, the data presented demonstrates the potential of a novel synthetic collagen mimetic as a hemostat.


Subject(s)
Collagen/chemistry , Hemostatics/chemistry , Hemostatics/pharmacology , Nanofibers/chemistry , Biomimetics , Hemostasis , Humans , Interleukin-1beta/metabolism , Molecular Mimicry , Monocytes/drug effects , Platelet Activation , Platelet Adhesiveness , Tissue Scaffolds , Tumor Necrosis Factor-alpha/metabolism
9.
Adv Physiol Educ ; 35(2): 206-12, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21652506

ABSTRACT

Cross-disciplinary (CD) learning experiences benefit student understanding of concepts and curriculum by offering opportunities to explore topics from the perspectives of alternate fields of study. This report involves a qualitative evaluation of CD health sciences undergraduate laboratory experiences in which concepts and students from two distinct disciplines [chemistry (CHEM) and exercise physiology (EPHE)] combined to study exercise thermoregulation and sweat analysis. Twenty-eight senior BSc Kinesiology (EPHE) students and 42 senior BSc CHEM students participated as part of their mutually exclusive, respective courses. The effectiveness of this laboratory environment was evaluated qualitatively using written comments collected from all students as well as from formal focus groups conducted after the CD laboratory with a representative cohort from each class (n = 16 CHEM students and 9 EPHE students). An open coding strategy was used to analyze the data from written feedback and focus group transcripts. Coding topics were generated and used to develop five themes found to be consistent for both groups of students. These themes reflected the common student perceptions that the CD experience was valuable and that students enjoyed being able to apply academic concepts to practical situations as well as the opportunity to interact with students from another discipline of study. However, students also reported some challenges throughout this experience that stemmed from the combination of laboratory groups from different disciplines with limited modification to the design of the original, pre-CD, learning environments. The results indicate that this laboratory created an effective learning opportunity that fostered student interest and enthusiasm for learning. The findings also provide information that could inform subsequent design and implementation of similar CD experiences to enhance engagement of all students and improve instructor efficacy.


Subject(s)
Body Temperature Regulation/physiology , Chemistry/education , Exercise/physiology , Interdisciplinary Communication , Students , Sweating/physiology , Biomechanical Phenomena/physiology , British Columbia , Clinical Laboratory Techniques , Curriculum , Educational Measurement , Educational Status , Feedback , Female , Focus Groups , Health Knowledge, Attitudes, Practice , Humans , Learning , Male , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL
...