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1.
Immunol Cell Biol ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39076101

RESUMEN

A hemocytometer is a key piece of laboratory equipment typically used in diagnostic and immunology research laboratories to enumerate white blood cells. The accurate quantification of cell density is essential to ensure accurate numbers of cells are added to assays to generate valid data. Hence, learning to correctly use a hemocytometer is a critical skill for all undergraduate immunology students. However, this skill can be challenging to learn because of students' unfamiliarity with correct cell identification, differentiating viable versus dead cells and mathematical proficiency in calculating cell density and viability. To address these issues, we developed an interactive computer simulation that replicated all aspects of a Neubauer-style hemocytometer. This simulation was used to teach second-year undergraduate immunology students before a face-to-face (F-2-F) laboratory exercise where these skills were applied. Using a mixed methods approach, student performance and feedback were collected on broad aspects of the intervention and its benefits to the F-2-F setting. The approach was found to be extremely successful with all measures indicating a significant impact of the virtual hemocytometer on student learning, understanding and confidence. We suggest that integrating an online simulation to teach students the fundamentals of hemocytometer use and calculations is a valuable educational aid for learning this important skill.

2.
Int J Sport Nutr Exerc Metab ; 29(6): 643-650, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31629350

RESUMEN

Food-based diet indices provide a practical, rapid, and inexpensive way of evaluating dietary intake. Rather than nutrients, diet indices assess the intake of whole foods and dietary patterns, and compare these with nutrition guidelines. An athlete-specific diet index would offer an efficient and practical way to assess the quality of athletes' diets, guide nutrition interventions, and focus sport nutrition support. This study describes the development and validation of an Athlete Diet Index (ADI). Item development was informed by a review of existing diet indices, relevant literature, and in-depth focus groups with 20 sports nutritionists (median of 11 years' professional experience) from four elite athlete sporting institutes. Focus group data were analyzed (NVivo 11 Pro; QSR International Pty. Ltd., 2017, Melbourne, Australia), and key themes were identified to guide the development of athlete-relevant items. A modified Delphi survey in a subgroup of sports nutritionists (n = 9) supported item content validation. Pilot testing with athletes (n = 15) subsequently informed face validity. The final ADI (n = 68 items) was categorized into three sections. Section A (n = 45 items) evaluated usual intake, special diets or intolerances, dietary habits, and culinary skills. Section B (n = 15 items) assessed training load, nutrition supporting training, and sports supplement use. Section C (n = 8 items) captured the demographic details, sporting type, and caliber. All of the athletes reported the ADI as easy (40%) or very easy (60% of participants) to use and rated the tool as relevant (37%) or very relevant (63% of participants) to athletes. Further evaluation of the ADI, including the development of a scoring matrix and validation compared with established dietary methodology, is warranted.


Asunto(s)
Atletas , Dieta , Conducta Alimentaria , Evaluación Nutricional , Estado Nutricional , Encuestas y Cuestionarios/normas , Femenino , Humanos , Masculino , Fenómenos Fisiológicos en la Nutrición Deportiva
3.
J Biol Chem ; 292(14): 5845-5859, 2017 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-28213522

RESUMEN

Type I interferons (IFN-I) are critical in antimicrobial and antitumor defense. Although IFN-I signal via the interferon-stimulated gene factor 3 (ISGF3) complex consisting of STAT1, STAT2, and IRF9, IFN-I can mediate significant biological effects via ISGF3-independent pathways. For example, the absence of STAT1, STAT2, or IRF9 exacerbates neurological disease in transgenic mice with CNS production of IFN-I. Here we determined the role of IFN-I-driven, ISGF3-independent signaling in regulating global gene expression in STAT1-, STAT2-, or IRF9-deficient murine mixed glial cell cultures (MGCs). Compared with WT, the expression of IFN-α-stimulated genes (ISGs) was reduced in number and magnitude in MGCs that lacked STAT1, STAT2, or IRF9. There were significantly fewer ISGs in the absence of STAT1 or STAT2 versus in the absence of IRF9. The majority of ISGs regulated in the STAT1-, STAT2-, or IRF9-deficient MGCs individually were shared with WT. However, only a minor number of ISGs were common to WT and STAT1-, STAT2-, and IRF9-deficient MGCs. Whereas signal pathway activation in response to IFN-α was rapid and transient in WT MGCs, this was delayed and prolonged and correlated with increased numbers of ISGs expressed at 12 h versus 4 h of IFN-α exposure in all three IFN-I signaling-deficient MGCs. In conclusion, 1) IFN-I can mediate ISG expression in MGCs via ISGF3-independent signaling pathways but with reduced efficiency, with delayed and prolonged kinetics, and is more dependent on STAT1 and STAT2 than IRF9; and 2) signaling pathways not involving STAT1, STAT2, or IRF9 play a minor role only in mediating ISG expression in MGCs.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/metabolismo , Interferón-alfa/farmacología , Neuroglía/metabolismo , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Factor 3 de Genes Estimulados por el Interferón/genética , Factor 3 de Genes Estimulados por el Interferón/metabolismo , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón/genética , Ratones , Ratones Noqueados , Neuroglía/citología , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT2/genética
4.
Glia ; 66(10): 2058-2078, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30051922

RESUMEN

Type I interferons (IFN-I) are crucial for effective antimicrobial defense in the central nervous system (CNS) but also can cause severe neurological disease (termed cerebral interferonopathy) as exemplified by Aicardi-Goutières Syndrome. In the CNS, microglia and astrocytes have essential roles in host responses to infection and injury, with both cell types responding to IFN-I. While the IFN-I signaling pathways are the same in astrocytes and microglia, the extent to which the IFN-I responses of these cells differ, if at all, is unknown. Here we determined the global transcriptional responses of astrocytes and microglia to the IFN-I, IFN-α. We found that under basal conditions, each cell type has a unique gene expression pattern reflective of its developmental origin and biological function. Following stimulation with IFN-α, astrocytes and microglia also displayed a common core response that was characterized by the increased expression of genes required for pathogen detection and elimination. Compared with astrocytes, microglia had a more extensive and diverse response to IFN-α with significantly more genes with expression upregulated (282 vs. 141) and downregulated (81 vs. 3). Further validation was documented for selected IFN-I-regulated genes in a murine model of cerebral interferonopathy. In all, the findings highlight not only overlapping but importantly divergent responses to IFN-I by astrocytes versus microglia. This suggests specialized roles for these cells in host defense and in the development of cerebral interferonopathy.


Asunto(s)
Astrocitos/metabolismo , Interferón-alfa/metabolismo , Microglía/metabolismo , Animales , Astrocitos/patología , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/fisiología , Interferón-alfa/administración & dosificación , Ratones Endogámicos C57BL , Microglía/patología , Deficiencias en la Proteostasis/metabolismo , Deficiencias en la Proteostasis/patología , Transcripción Genética
5.
Eur J Immunol ; 43(2): 510-20, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23129528

RESUMEN

The fine control of T-cell differentiation and its impact on HIV disease states is poorly understood. In this study, we demonstrate that B-lymphocyte-induced maturation protein-1 (Blimp-1/Prdm1) is highly expressed in CD4(+) T cells from chronically HIV-infected (CHI) patients compared to cells from long-term nonprogressors or healthy controls. Stimulation through the T-cell receptor in the presence of IL-2 induces Blimp-1 protein expression. We show here that Blimp-1 levels are translationally regulated by microRNA-9 (miR-9). Overexpression of miR-9 induces Blimp-1 repression, restoring IL-2 secretion in CD4(+) T cells via reduction in the binding of Blimp-1 to the il-2 promoter. In CHI patients where IL-2 expression is reduced and there is generalized T-cell dysfunction, we show differential expression of both miR-9 and Blimp-1 in CD4(+) cells compared with levels in long-term nonprogressors. These data identify a novel miR-9/Blimp-1/IL-2 axis that is dysregulated in progressive HIV infection.


Asunto(s)
Linfocitos B/metabolismo , Infecciones por VIH/metabolismo , Interleucina-2/metabolismo , MicroARNs/genética , Proteínas Represoras/metabolismo , Adulto , Linfocitos B/inmunología , Linfocitos B/virología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Línea Celular Tumoral , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Femenino , Infecciones por VIH/genética , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Interleucina-2/genética , Interleucina-2/inmunología , Células Jurkat , Masculino , MicroARNs/inmunología , MicroARNs/metabolismo , Persona de Mediana Edad , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/inmunología , Regulación hacia Arriba/genética , Regulación hacia Arriba/inmunología , Adulto Joven
6.
J Am Coll Nutr ; 31(3): 185-93, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23204155

RESUMEN

OBJECTIVE: To examine the association between intake of dairy products and indicators of diet quality among a sample of Australian children. METHODS: Three 24-hour recalls were collected from 222 children aged 8-10 years living in western Sydney. Analysis of covariance was used to examine differences in mean intakes of foods and nutrients among 3 dairy consumption groups (<1 serve, 1-2 serves, ≥2 serves per day). The percentage of children meeting healthy eating guidelines for foods and estimated average requirements (EAR) for nutrients was also assessed. RESULTS: Higher dairy consumption was associated with higher intakes of energy, protein, calcium, phosphorus, magnesium, potassium, zinc, vitamin A, riboflavin, and niacin as well as foods from the bread and cereal group but lower intakes of mono- and polyunsaturated fats, foods from the meat and alternatives group, and energy-dense, nutrient-poor foods. Children who consumed ≥2 serves of dairy products per day (38%) were more likely to meet food and nutrient recommendations. Body mass index z-score and waist circumference were not associated with dairy consumption. Milk intake was inversely associated with the intake of sugar-sweetened beverages, and children who did not meet their minimum dairy serve recommendations consumed higher quantities of sugar-sweetened beverages than milk. CONCLUSIONS: Adequate dairy consumption was associated with diets of higher nutritional quality but also higher intakes of energy, suggesting a potential benefit from shifting consumption from regular-fat to reduced-fat dairy products in line with current national recommendations.


Asunto(s)
Fenómenos Fisiológicos Nutricionales Infantiles/fisiología , Productos Lácteos , Dieta/normas , Política Nutricional , Niño , Dieta/estadística & datos numéricos , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/efectos adversos , Ingestión de Energía , Femenino , Humanos , Masculino , Recuerdo Mental , Nueva Gales del Sur , Necesidades Nutricionales , Estado Nutricional , Control de Calidad , Aumento de Peso
7.
Br J Nutr ; 107(12): 1871-80, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22018024

RESUMEN

The aim of the present study was to investigate and benchmark the level of general nutrition knowledge in elite Australian athletes (EA) against a similar aged community (CM) and criterion sample with dietetic training (DT). EA (n 175), CM (n 116) and DT (n 53) completed the General Nutrition Knowledge Questionnaire (GNKQ), which assesses four domains (sections A-D) of general nutrition knowledge (section A: dietary guidelines; section B: sources of nutrients; section C: choosing everyday foods; section D: diet-disease relationships). Age, sex and education level were collected in all groups, and athletic calibre and sport type (team or individual) in EA. Dietitians and nutrition scientists (n 53) re-examined the GNKQ for content validity, resulting in instrument revision (R-GNKQ; ninety-six items). Psychometric assessment (internal consistency: Cronbach-α; test-retest: Spearman rank correlation) was performed in a sub-sample (n 28). Independent t tests, ANOVA and ANCOVA (χ² for categorical variables) were used to assess between-group differences. DT scored higher than EA and CM in all sub-sections and overall (P < 0·005). EA scored lower than CM in GNKQ for section B (P < 0·005) and overall (P < 0·005), and in R-GNKQ for section B (P < 0·005), section C (P < 0·005), section D (P = 0·006) and overall (P < 0·005). Overall score was influenced by age (P = 0·036 for GNKQ: P = 0·053 for R-GNKQ), sex (P = 0·016 for GNKQ: P = 0·003 for R-GNKQ) and athletic calibre (P = 0·029 for R-GNKQ only), but not level of education, living situation or ethnicity. EA and CM performed best on section A and worst on D. EA had lower overall general knowledge scores than CM. This was significantly influenced by age and sex.


Asunto(s)
Atletas , Dieta , Dietética , Conducta Alimentaria , Guías como Asunto , Conocimientos, Actitudes y Práctica en Salud , Adolescente , Adulto , Factores de Edad , Análisis de Varianza , Australia , Benchmarking , Femenino , Salud , Humanos , Masculino , Psicometría , Factores Sexuales , Adulto Joven
8.
J Microbiol Biol Educ ; 23(2)2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36061312

RESUMEN

Determining the antibiotic sensitivity of disease-causing microorganisms is a fundamental process in a clinical microbiology laboratory. With the continued use of antibiotics, the emergence of antibiotic resistance has become a significant health issue. However, the principles and laboratory testing to determine antibiotic sensitivity are generally not taught to first-year undergraduate students. This is partly due to the limited time to cover the fundamental biology of microorganisms and the mechanism of action of antibiotics in an introductory course. We overcame these limitations by teaching first-year students the fundamental principles of antibiotic sensitivity using an online data generator/simulation. Using the Kirby-Bauer disk diffusion test, students replicated the effects of antibiotic dose on bacterial growth and determined the antimicrobial susceptibility testing of their allocated bacterium. After 2-3 weeks, the antimicrobial sensitivity testing was replicated in an authentic face-to-face laboratory setting over 2 days. The impact of the intervention on student learning was assessed using a written laboratory report and a short questionnaire containing Likert and free-text questions. Student self-reported understanding of the content rose significantly, with nearly all students passing the written assessment. The approach was found to be enjoyable and interactive and facilitated authentic learning in first-year students. This cohort of students will continue to use more advanced versions of this simulation in future years, allowing for the long-term benefits of this approach to be assessed.

9.
CBE Life Sci Educ ; 21(1): ar4, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34941363

RESUMEN

A critical goal for science education is to design and implement learning activities that develop a deep conceptual understanding, are engaging for students, and are scalable for large classes or those with few resources. Approaches based on peer learning and online technologies show promise for scalability but often lack a grounding in cognitive learning principles relating to conceptual understanding. Here, we present a novel design for combining these elements in a principled way. The design centers on having students author multiple-choice questions for their peers using the online platform PeerWise, where beneficial forms of cognitive engagement are encouraged via a series of supporting activities. We evaluated an implementation of this design within a cohort of 632 students in an undergraduate biochemistry course. Our results show a robust relationship between the quality of question authoring and relevant learning outcomes, even after controlling for the confounding influence of prior grades. We conclude by discussing practical and theoretical implications.


Asunto(s)
Evaluación Educacional , Estudiantes , Humanos , Aprendizaje , Motivación , Grupo Paritario
10.
J Cell Physiol ; 226(6): 1479-88, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20945389

RESUMEN

The prostate stromal mesenchyme controls organ-specific development. In cancer, the stromal compartment shows altered gene expression compared to non-cancer. The lineage relationship between cancer-associated stromal cells and normal tissue stromal cells is not known. Nor is the cause underlying the expression difference. Previously, the embryonal carcinoma (EC) cell line, NCCIT, was used by us to study the stromal induction property. In the current study, stromal cells from non-cancer (NP) and cancer (CP) were isolated from tissue specimens and co-cultured with NCCIT cells in a trans-well format to preclude heterotypic cell contact. After 3 days, the stromal cells were analyzed by gene arrays for microRNA (miRNA) and mRNA expression. In co-culture, NCCIT cells were found to alter the miRNA and mRNA expression of NP stromal cells to one like that of CP stromal cells. In contrast, NCCIT had no significant effect on the gene expression of CP stromal cells. We conclude that the gene expression changes in stromal cells can be induced by diffusible factors synthesized by EC cells, and suggest that cancer-associated stromal cells represent a more primitive or less differentiated stromal cell type.


Asunto(s)
Células Madre de Carcinoma Embrionario/metabolismo , MicroARNs/genética , Próstata/metabolismo , Próstata/patología , Comunicación Celular , Línea Celular Tumoral , Forma de la Célula , Técnicas de Cocultivo , Medios de Cultivo , Citoplasma/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Células del Estroma/metabolismo , Células del Estroma/patología
11.
Am J Hum Genet ; 83(3): 388-400, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18771760

RESUMEN

Down syndrome (DS) is the most common cause of mental retardation. Many neural phenotypes are shared between DS individuals and DS mouse models; however, the common underlying molecular pathogenetic mechanisms remain unclear. Using a transchromosomic model of DS, we show that a 30%-60% reduced expression of Nrsf/Rest (a key regulator of pluripotency and neuronal differentiation) is an alteration that persists in trisomy 21 from undifferentiated embryonic stem (ES) cells to adult brain and is reproducible across several DS models. Using partially trisomic ES cells, we map this effect to a three-gene segment of HSA21, containing DYRK1A. We independently identify the same locus as the most significant eQTL controlling REST expression in the human genome. We show that specifically silencing the third copy of DYRK1A rescues Rest levels, and we demonstrate altered Rest expression in response to inhibition of DYRK1A expression or kinase activity, and in a transgenic Dyrk1A mouse. We reveal that undifferentiated trisomy 21 ES cells show DYRK1A-dose-sensitive reductions in levels of some pluripotency regulators, causing premature expression of transcription factors driving early endodermal and mesodermal differentiation, partially overlapping recently reported downstream effects of Rest +/-. They produce embryoid bodies with elevated levels of the primitive endoderm progenitor marker Gata4 and a strongly reduced neuroectodermal progenitor compartment. Our results suggest that DYRK1A-mediated deregulation of REST is a very early pathological consequence of trisomy 21 with potential to disturb the development of all embryonic lineages, warranting closer research into its contribution to DS pathology and new rationales for therapeutic approaches.


Asunto(s)
Síndrome de Down/metabolismo , Células Madre Embrionarias/patología , Dosificación de Gen , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Tirosina Quinasas/fisiología , Proteínas Represoras/fisiología , Animales , Diferenciación Celular , Modelos Animales de Enfermedad , Síndrome de Down/genética , Síndrome de Down/patología , Células Madre Embrionarias/fisiología , Regulación del Desarrollo de la Expresión Génica , Humanos , Ratones , Ratones Transgénicos , Células Madre Pluripotentes/patología , Células Madre Pluripotentes/fisiología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Sitios de Carácter Cuantitativo , Proteínas Represoras/genética , Quinasas DyrK
12.
Blood ; 113(19): 4575-85, 2009 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-19204323

RESUMEN

Peripheral tolerance induction is critical for the maintenance of self-tolerance and can be mediated by immunoregulatory T cells or by direct induction of T-cell anergy or deletion. Although the molecular processes underlying anergy have been extensively studied, little is known about the molecular basis for peripheral T-cell deletion. Here, we determined the gene expression signature of peripheral CD8(+) T cells undergoing deletional tolerance, relative to those undergoing immunogenic priming or lymphopenia-induced proliferation. From these data, we report the first detailed molecular signature of cells undergoing deletion. Consistent with defective cytolysis, these cells exhibited deficiencies in granzyme up-regulation. Furthermore, they showed antigen-driven Bcl-2 down-regulation and early up-regulation of the proapoptotic protein Bim, consistent with the requirement of this BH3-only protein for peripheral T-cell deletion. Bim up-regulation was paralleled by defective interleukin-7 receptor alpha (IL-7Ralpha) chain reexpression, suggesting that Bim-dependent death may be triggered by loss of IL-7/IL-7R signaling. Finally, we observed parallels in molecular signatures between deletion and anergy, suggesting that these tolerance pathways may not be as molecularly distinct as previously surmised.


Asunto(s)
Apoptosis/fisiología , Biomarcadores/metabolismo , Linfocitos T CD8-positivos/fisiología , Transducción de Señal , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Citometría de Flujo , Perfilación de la Expresión Génica , Granzimas/metabolismo , Proteínas de Homeodominio/fisiología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/metabolismo
13.
Mol Cell Proteomics ; 8(4): 585-95, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19001410

RESUMEN

Down syndrome, caused by the trisomy of chromosome 21, is a complex condition characterized by a number of phenotypic features, including reduced neuron number and synaptic plasticity, early Alzheimer disease-like neurodegeneration, craniofacial dysmorphia, heart development defects, increased incidence of childhood leukemia, and powerful suppression of the incidence of most solid tumors. Mouse models replicate a number of these phenotypes. The Tc1 Down syndrome model was constructed by introducing a single supernumerary human chromosome 21 into a mouse embryonic stem cell, and it reproduces a large number of Down syndrome phenotypes including heart development defects. However, little is still known about the developmental onset of the trisomy 21-induced mechanisms behind these phenotypes or the proteins that are responsible for them. This study determined the proteomic differences that are present in undifferentiated embryonic stem cells and are caused by an additional human chromosome 21. A total of 1661 proteins were identified using two-dimensional liquid chromatography followed by tandem mass spectrometry from whole embryonic stem cell lysates. Using isobaric tags for relative and absolute quantification, we found 52 proteins that differed in expression by greater than two standard deviations from the mean when an extra human chromosome 21 was present. Of these, at least 11 have a possible functional association with a Down syndrome phenotype or a human chromosome 21-encoded gene. This study also showed that quantitative protein expression differences in embryonic stem cells can persist to adult mouse as well as reproduce in human Down syndrome fetal tissue. This indicates that changes that are determined in embryonic stem cells of Down syndrome could potentially identify proteins that are involved in phenotypes of Down syndrome, and it shows that these cell lines can be used for the purpose of studying these pathomechanisms.


Asunto(s)
Síndrome de Down/metabolismo , Células Madre Embrionarias/metabolismo , Proteómica , Animales , Western Blotting , Línea Celular , Cromosomas Humanos Par 21/metabolismo , Modelos Animales de Enfermedad , Feto/metabolismo , Feto/patología , Humanos , Ratones , Péptidos/metabolismo , Proteínas/metabolismo , Reproducibilidad de los Resultados , Coloración y Etiquetado
14.
J Nutr Educ Behav ; 52(6): 607-614, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31786068

RESUMEN

OBJECTIVE: To validate an electronic nutrition literacy assessment tool (e-NutLit). DESIGN: Cross-sectional. SETTING: An Australian teaching hospital obesity clinic (clinical cohort) and university (dietetic cohort). PARTICIPANTS: A convenience sample of patients with obesity (body mass index > 35 kg m-2) (obese participants [OP]) and dietetic interns (DI). INTERVENTIONS: The e-NutLit was administered to OP and scores were compared with performance on the Newest Vital Sign and e-NutLit scores of the DI to establish construct validity. A subset of OP completed the e-NutLit again to examine instrument temporal stability. Internal consistency was assessed using Cronbach α. MAIN OUTCOME MEASURES: Construct validity, temporal stability, and internal consistency. ANALYSIS: Parametric and nonparametric tests and general linear modeling were used as appropriate. RESULTS: A total of 103 participants completed the study (OP: n = 59; 64.4% female; DI: n = 44; 86.4% female). Newest Vital Sign and e-NutLit scores were significantly and positively associated (rs = 0.66; P <.001). The DI performed significantly better than the OP (OP: 59.7 ± 13.1 percentage points; DI: 83.9 ±â€¯5.5 percentage points; P <.001), further supporting construct validity. The e-NutLit Cronbach α was >0.9 indicating a good level of internal consistency. The OP test and retest scores were not significantly different, supporting instrument temporal stability. CONCLUSION AND IMPLICATIONS: The results support the validity of the e-NutLit, for both clinicians and researchers.


Asunto(s)
Educación en Salud , Alfabetización en Salud , Fenómenos Fisiológicos de la Nutrición/fisiología , Encuestas y Cuestionarios , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Obesidad , Adulto Joven
15.
Protein Sci ; 29(1): 157-168, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31622516

RESUMEN

A key learning outcome for undergraduate biochemistry classes is a thorough understanding of the principles of protein structure. Traditional approaches to teaching this material, which include two-dimensional (2D) images on paper, physical molecular modeling kits, and projections of 3D structures into 2D, are unable to fully capture the dynamic 3D nature of proteins. We have built a virtual reality application, Peppy, aimed at facilitating teaching of the principles of protein secondary structure. Rather than attempt to model molecules with the same fidelity to the underlying physical chemistry as existing, research-oriented molecular modelling approaches, we took the more straightforward approach of harnessing the Unity video game physics engine. Indeed, the simplicity and limitations of our model are strengths in a teaching context, provoking questions and thus deeper understanding. Peppy allows exploration of the relative effects of hydrogen bonding (and electrostatic interactions more generally), backbone φ/ψ angles, basic chemical structure, and steric effects on a polypeptide structure in an accessible format that is novel, dynamic, and fun to use. Apart from describing the implementation and use of Peppy, we discuss the outcomes of deploying Peppy in undergraduate biochemistry courses.


Asunto(s)
Bioquímica/educación , Péptidos/química , Humanos , Enlace de Hidrógeno , Modelos Moleculares , Estructura Secundaria de Proteína , Interfaz Usuario-Computador , Juegos de Video , Realidad Virtual
16.
Br J Nutr ; 101(12): 1878-84, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19055852

RESUMEN

The insulin-like growth factor (IGF) system is altered with intra-uterine growth retardation and in adult metabolic disease. The aim of the present study was to observe effects of continued protein restriction on the IGF-I system and body composition in offspring of mothers fed a low-protein (LP) diet. Offspring from Wistar dams fed either a 20 % (CON) or 8 % (LP) protein diet during gestation and lactation were studied at birth, 10 d, weaning and at 12 weeks after maintenance on either the 8 % (lp) or 20 % (con) protein diet from weaning. LP offspring had reduced weaning weights (P < 0.05) and reduced serum insulin (P < 0.005). Serum IGF-I (P < 0.001) and acid-labile subunit (ALS) (P < 0.0001) were reduced at 10 and 21 d. Hepatic expression of IGF-I (P < 0.05) and ALS (P < 0.005) were reduced at 10 and 21 d. IGF binding protein (IGFBP)-1 hepatic expression was elevated at 10 d (P < 0.001) but not at 21 d. Adult LP-con offspring had reduced body weight (P < 0.05), lean (P < 0.0001) and bone (P < 0.0001) but not fat (P = 0.6) mass with no persistent effects on IGF-I, ALS and IGFBP-1.Postnatal lp feeding reduced lean mass (P < 0.0001) and bone mass (P < 0.0001) in CON and LP animals. Percentage fat (LP P = 0.04; CON P = 0.6) and IGFBP-1 (LP P = 0.01; CON P = 0.2) were increased in LP-lp but not CON-lp offspring. This suggests that postnatal nutrition is important in the effects of maternal protein restriction on adult body composition and that IGFBP-1 may be involved.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Animales Recién Nacidos/crecimiento & desarrollo , Dieta con Restricción de Proteínas , Fenómenos Fisiologicos Nutricionales Maternos , Efectos Tardíos de la Exposición Prenatal , Alimentación Animal , Animales , Animales Recién Nacidos/metabolismo , Composición Corporal , Peso Corporal , Proteínas Portadoras/sangre , Femenino , Glicoproteínas/sangre , Insulina/sangre , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/análisis , Lactancia/fisiología , Hígado/química , Embarazo , Ratas , Ratas Wistar , Factores de Tiempo , Destete
17.
Am J Clin Nutr ; 87(1): 247S-257S, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18175765

RESUMEN

BACKGROUND: Many laboratories offer glycemic index (GI) services. OBJECTIVE: We assessed the performance of the method used to measure GI. DESIGN: The GI of cheese-puffs and fruit-leather (centrally provided) was measured in 28 laboratories (n=311 subjects) by using the FAO/WHO method. The laboratories reported the results of their calculations and sent the raw data for recalculation centrally. RESULTS: Values for the incremental area under the curve (AUC) reported by 54% of the laboratories differed from central calculations. Because of this and other differences in data analysis, 19% of reported food GI values differed by >5 units from those calculated centrally. GI values in individual subjects were unrelated to age, sex, ethnicity, body mass index, or AUC but were negatively related to within-individual variation (P=0.033) expressed as the CV of the AUC for repeated reference food tests (refCV). The between-laboratory GI values (mean+/-SD) for cheese-puffs and fruit-leather were 74.3+/-10.5 and 33.2+/-7.2, respectively. The mean laboratory GI was related to refCV (P=0.003) and the type of restrictions on alcohol consumption before the test (P=0.006, r2=0.509 for model). The within-laboratory SD of GI was related to refCV (P<0.001), the glucose analysis method (P=0.010), whether glucose measures were duplicated (P=0.008), and restrictions on dinner the night before (P=0.013, r2=0.810 for model). CONCLUSIONS: The between-laboratory SD of the GI values is approximately 9. Standardized data analysis and low within-subject variation (refCV<30%) are required for accuracy. The results suggest that common misconceptions exist about which factors do and do not need to be controlled to improve precision. Controlled studies and cost-benefit analyses are needed to optimize GI methodology. The trial was registered at clinicaltrials.gov as NCT00260858.


Asunto(s)
Técnicas de Laboratorio Clínico/normas , Carbohidratos de la Dieta/metabolismo , Análisis de los Alimentos/normas , Alimentos/clasificación , Índice Glucémico , Adolescente , Adulto , Anciano , Área Bajo la Curva , Glucemia/metabolismo , Estudios Cruzados , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Biochem Mol Biol Educ ; 46(4): 306-317, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29528559

RESUMEN

Disciplines such as Biochemistry and Molecular Biology, which involve concepts not included in the high-school curriculum, are very challenging for many first year university students. These subjects are particularly difficult for students accustomed to surface learning strategies involving memorization and recall of facts, as a deeper understanding of the relationship between concepts is needed for successful transfer to related areas and subsequent study. In this article, we explore an activity in a very large first year Molecular Biology course, in which students create multiple-choice questions related to targeted learning outcomes, and then answer and evaluate one another's questions. This activity encompasses elements of both self- and peer-assessment and the generative tasks of creating questions and producing written feedback may contribute to a deeper understanding of the material. We make use of a free online platform to facilitate all aspects of the process and analyze the effect of student engagement with the task on overall course performance. When compared to previous semester's cohorts, we observe a pronounced improvement in class performance on exam questions targeting similar concepts to the student-generated questions. In addition, those students that engage to a greater extent with the activity perform significantly better on the targeted exam questions than those who are less active, yet all students perform similarly on a set of isolated control questions appearing on the same exam. © 2018 by The International Union of Biochemistry and Molecular Biology, 46:306-317, 2018.


Asunto(s)
Aprendizaje Basado en Problemas , Evaluación Educacional , Humanos , Biología Molecular , Estudiantes
19.
Nutrients ; 10(2)2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-29473889

RESUMEN

Nutrition literacy is linked to health via its influence on dietary intake. There is a need for a tool to assess nutrition literacy in research and dietetic practice. We sought guidance from nutrition professionals on topic areas and features of an electronic nutrition literacy assessment tool for Australian adults. 28 experienced nutrition professionals engaged in a range of nutrition and dietetic work areas participated in six focus groups using a semi-structured interview schedule. Data were analysed using an inductive approach using NVivo 10 (QSR International, Pty Ltd., Doncaster, Australia, 2012). Key areas identified to assess nutrition literacy included specific nutrients versus foods, labels and packaging, construction of the diet, knowledge of the Australian Dietary Guidelines and Australian Guide to Healthy Eating, understanding of serve and portion sizes, ability to select healthier foods, and demographics such as belief systems and culture. Exploitation of electronic features to enhance visual and auditory displays, including interactive animations such as "drag and drop" and virtual reality situations, were discussed. This study provided insight into the most relevant topic areas and presentation format to assess the nutrition literacy of adult Australians. The visual, auditory, and interactive capacity of the available technology could enhance the assessment of nutrition literacy.


Asunto(s)
Recolección de Datos , Dietética/educación , Conocimientos, Actitudes y Práctica en Salud , Alfabetización en Salud , Estado Nutricional , Adulto , Australia , Conducta de Elección , Dieta Saludable , Estudios de Evaluación como Asunto , Grupos Focales , Embalaje de Alimentos , Preferencias Alimentarias , Humanos , Política Nutricional , Tamaño de la Porción , Factores Socioeconómicos , Encuestas y Cuestionarios
20.
J Mech Behav Biomed Mater ; 88: 11-17, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30118920

RESUMEN

We have an interest in the cellular response to mechanical stimuli, and here describe an in-vitro method to examine the response of cells cultured in a three-dimensional matrix to mechanical compressive and tensile stress. Synthetic aliphatic polyester scaffolds coated with 45S5 bioactive glass were seeded with human dental follicular cells (HDFC), and attached to well inserts and magnetic endplates in six well palates. Scaffolds were subjected to either cyclic 10% tensile deformation, or 8% compression, at 1 Hz and 2 Hz respectively for 6, 24 or 48 h, by uniaxial motion of magnetically-coupled endplates. It was possible to isolate high quality mRNA from cells in these scaffolds, as demonstrated by high RNA integrity numbers scores, and ability to perform meaningful cRNA microarray analysis, in which 669 and 727 genes were consistently upregulated, and 662 and 518 genes down regulated at all times studied under tensile and compressive loading conditions respectively. MetaCore analysis revealed the most regulated gene ontogenies under both loading conditions to be for: cytoskeletal remodelling; cell adhesion-chemokines and adhesion; cytoskeleton remodelling-TGF WNT and cytoskeletal remodelling pathways. We believe the method here described will be of value for analysis of the cellular response to cyclic loading.


Asunto(s)
Fuerza Compresiva , Saco Dental/citología , Estrés Mecánico , Fenómenos Biomecánicos , Saco Dental/metabolismo , Regulación de la Expresión Génica , Humanos
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