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1.
J Nat Prod ; 73(6): 1173-6, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20575589

RESUMO

Three new bastadins, bastadin 25 (1), 15-O-sulfonatobastadin 11 (2), and bastadin 26 (3), were isolated from a MeOH extract of the Australian marine sponge Ianthella flabelliformis. Their structures were determined by interpretation of 1D and 2D NMR spectra and mass spectrometry. Bastadin 26 (3) showed potent affinity for the guinea pig delta-opioid receptors with a K(i) value of 100 nM. The other two bastadins had a 100-fold lower affinity. The three compounds were also tested for their affinity to guinea pig micro- and kappa-opioid receptors and shown to have either no affinity or only very weak affinity toward both of these opioid receptors.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/farmacologia , Poríferos/química , Receptores Opioides delta/efeitos dos fármacos , Algoritmos , Animais , Austrália , Encéfalo/efeitos dos fármacos , Cobaias , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/química , Receptores Opioides kappa/efeitos dos fármacos , Receptores Opioides mu/efeitos dos fármacos
2.
J Nat Prod ; 71(9): 1564-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18771320

RESUMO

High-throughput screening of a plant and marine invertebrate extract library to find natural products with rat thyrotropin-releasing hormone (TRH) receptor-2 binding affinity led to the isolation of four new, myrtucommulones F-I (3-6), and two known, myrtucommulones A (1) and D (2), active acylphloroglucinols from the seeds of the Queensland tree Corymbia scabrida. Their structures were assigned from interpretation of 2D NMR and high-resolution ESIMS data. The relative configuration of the stereogenic centers for all six compounds was deduced from ROESY correlations. This is the first time that myrtucommulone A (1) has been isolated as a single pure compound. The structure of myrtucommulone D (2) has been revised. Myrtucommulones A, D, and F-I showed rat TRH receptor-2 binding affinity with IC50 values of 39, 11, 16, 24, 31, and 16 microM, respectively.


Assuntos
Myrtaceae/química , Floroglucinol/análogos & derivados , Plantas Medicinais/química , Receptores do Hormônio Liberador da Tireotropina/metabolismo , Animais , Estrutura Molecular , Floroglucinol/química , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Queensland , Ratos , Sementes/química
3.
Adv Physiol Educ ; 32(1): 47-54, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18334568

RESUMO

We previously reported how the opinions of second-year dentistry students and faculty members can be used to construct an assessment rubric to grade group-based concept maps in physiology. This article describes the second phase of this study of the subsequent year's cohort. A case study approach was used to investigate how groups of students used the criteria to complete their complex concept maps. Students' opinions about the assessment task and newly constructed rubric were sampled. Opinions across groups were correlated to academic achievements in the course. Two groups of four students volunteered to be videorecorded during a 4-h workshop, during which they completed their maps. The mapping task was not generally favored by students. However, those students who did favor the task achieved higher academic grades. Most students favored the newly constructed assessment rubric, commenting that it was easy to understand, fair, and appropriate, but reported that extra guidance from tutors and other resources were required. Coded videorecordings of the two observation groups revealed complex interactions around the three criteria of content, logic and understanding, and presentation. Two broad patterns of working were identified. One group distributed their efforts more evenly across the criteria, whereas the other group completed their maps by addressing the criteria in stages. These findings clearly indicate the academic challenges and social complexity in how students work in groups to complete complex concept maps in physiology.


Assuntos
Percepção , Fisiologia/educação , Aprendizagem Baseada em Problemas , Estudantes de Odontologia , Formação de Conceito , Coleta de Dados , Educação em Odontologia , Avaliação Educacional , Feminino , Humanos , Masculino , Modelos Educacionais
4.
Adv Physiol Educ ; 31(2): 167-75, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17562906

RESUMO

The media role model was recently developed to frame how science faculty members can teach their students to write more effectively to lay audiences (14). An Opinion Editorial (Op-Ed) was introduced as a novel assignment for final-year physiology and pharmacology undergraduates. This second phase of this study, reported here, demonstrated the efficacy of explicit teaching of the Op-Ed, using a one-shot, pre-/posttest research design. Baseline writing skills of students were determined from a communication assignment. Students were then explicitly taught how to write an Op-Ed and subsequently wrote an Op-Ed based on a recent, relevant scientific article. Most students achieved higher grades for their Op-Ed following explicit teaching [mean (SD) = 84.4% (9.1%), n = 216] compared with their communication assignment [mean (SD) = 74.7% (11.9%), n = 218]. Improvement in student writing was also evident by an increase in text readability, which mirrored the features of Op-Eds written by professional journalists. A survey of students (n = 142) indicated that most believed that the assignments were valuable and that their ability to write to a lay audience had improved. Members of the lay public were then surveyed for their opinions on student writing. Two assignments were selected from one student whose grades had improved after explicit teaching. Respondents (n = 78) indicated that the Op-Ed was easier to read than the communication assignment. Thus, explicit teaching of the Op-Ed improved the ability of students to write to members of the lay public.


Assuntos
Disciplinas das Ciências Biológicas/educação , Docentes , Aprendizagem , Estudantes , Ensino/métodos , Redação , Adolescente , Adulto , Avaliação Educacional , Humanos , Farmacologia/educação , Fisiologia/educação , Leitura
5.
Adv Physiol Educ ; 31(3): 266-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17848593

RESUMO

Responding to the concern from our faculty that undergraduate students do not have robust laboratory skills, we designed and implemented a strategy to individually teach and assess the manipulative skills of students in first-year laboratories. Five core laboratory skills were selected for the course entitled Human Biology, a large, first-year class of students, most of whom were enrolled in Bachelor of Pharmacy and Human Movement Studies. Here, we report details for the 365 students enrolled primarily in Pharmacy and Human Movement Studies bachelor degree programs in semester 1 of 2006. We designed a specific strategy to assess five core laboratory skills: 1) accurate and precise use of a micropipette, 2) calculation of dilutions and preparation of diluted samples of saline, 3) accurate representation of data using a graph, 4) use of a light microscope, and 5) acquisition of digital data by measuring the latent period for the Achilles reflex. Graduate tutors were trained to teach and assess each student on each skill. The development of competency was tracked for all students across all five skills. Most students demonstrated proficiency on their first attempt. The development of proficiency across the core skills depended on both the skill and degree program. In semester 2 of 2006, 854 students mostly enrolled in the Bachelor of Science degree program and were similarly taught and assessed on the same five core skills. This approach was an effective teaching and assessment strategy that, when applied beyond first year, should increase the level of laboratory skills across undergraduate programs in physiology.


Assuntos
Laboratórios/organização & administração , Competência Profissional , Humanos , Movimento , Farmacologia/educação , Queensland
6.
Biochem Mol Biol Educ ; 35(2): 89-96, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21591067

RESUMO

The teaching of highly valued scientific writing skills in the first year of university is challenging. This report describes the design, implementation, and evaluation of a novel written assignment, The Personal Response and accompanying Peer Review, in the course, Human Biology (BIOL1015) at The University of Queensland. These assignments were the first assessment tasks of the course and were set early in the first semester of university. BIOL1015 had a diverse cohort of 319 first year students from five bachelor degree programs, primarily from Pharmacy and Human Movement Studies. Audio files in the form of interviews with eminent biomedical scientists were obtained from a leading public radio program. Students used these files as triggers to submit a short but highly structured assignment written from a personal perspective and in an expressive style. Evaluations revealed that overall, students found the task interesting and challenging. Students performed well, regardless of their background knowledge, disciplinary interest, or preference for topics within human biology. This study demonstrated that The Personal Response was an appropriate task for these first year students of human biology. It represents an alternative to traditional essay writing.

7.
Biochem Mol Biol Educ ; 35(4): 255-62, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21591102

RESUMO

We detail the design, implementation and evaluation of an eConference entitled "Biohorizons", using a presage-process-product model to describe the development of an eLearning community. Biohorizons was a summative learning and assessment task aiming to introduce large classes of first-year Human Biology students to the practices of professional scientists. It was implemented in semester 1 for students enrolled in Pharmacy and Human Movement Studies degree programs, and in semester 2, for Science students. Pairs of students selected a topic of interest in Human Biology, registered into on-line clusters, then developed and wrote a short scientific paper and accompanying PowerPoint presentation. They then individually participated in an online Discussion. All three tasks were assessed using standards-referenced assessment rubrics. Learning was supported by eTutors, working in asynchronous mode. Biohorizons was evaluated by analyzing student achievement data, surveys and focus group interviews. Most students were able to achieve high academic standards (global mean scores for semester 1, 85-96%; semester 2, 81-90%). Student evaluations support: 1) the successful integration of eLearning into large classes of Human Biology, 2) the engagement of first-year students through collaborative learning, and 3) the fostering of learning through challenging assessment relevant to the core practices of professional scientists.

8.
Adv Physiol Educ ; 30(2): 73-82, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16709737

RESUMO

Improving the public understanding of science is an important challenge for the future professional scientists who are our current undergraduates. In this paper, we present a conceptual model that explores the role of mass media as community gatekeepers of new scientific findings. This model frames the benefits for undergraduate science students to learn about media genres so that they can learn to communicate science more effectively to nonprofessional audiences. Informed by this Media Role model, we then detail a novel writing task for undergraduate physiology students, the Opinion Editorial (Op-Ed), and an accompanying Peer Review. The Op-Ed genre was directly taught to the students by a professional journalist. As an assessment task, students presented a recent, highly technical paper as an Op-Ed. This was assessed by both faculty members and peers using a detailed assessment rubric. Most students were able to replicate the features of Op-Eds and attained high grades on their writing tasks. Survey data from final-year physiology students (n = 230) were collected before and after the implementation of the Op-Ed/Peer Review. These indicated that most students were aware of the importance of scientists to effectively communicate their knowledge to nonprofessional audiences, that the Op-Ed writing task was challenging, and that they believed that their ability to write to nonprofessional audiences was improved after explicit teaching and feedback.


Assuntos
Educação de Graduação em Medicina/métodos , Publicações Periódicas como Assunto , Ensino/métodos , Humanos , Meios de Comunicação de Massa
9.
Adv Physiol Educ ; 29(4): 197-203, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16298956

RESUMO

Constructing quality assessment rubrics can be challenging, especially when they are used for integrated, group-centered, applied learning. We describe a collaborative assessment task in which groups of second-year dentistry students developed a complex concept map. In groups of four, the students were given a written, simulated, medical history of a patient and required to construct a concept map illustrating relevant pathophysiological concepts and pharmacological interventions. This report describes a research project aimed at making educational goals of the task more explicit through investigating student and faculty member understandings of the criteria that might be used to assess the concept map. Information was gathered about the perceptions of students in relation to the learning goals associated with the task. These were compared with faculty member perceptions. The findings were used to develop an assessment rubric intended to be more accessible to learners. The new rubric used the language of both faculty members and students to more clearly represent expectations of each criterion and standard. This assessment rubric will be used in 2005 for the next phase of the project.


Assuntos
Coleta de Dados , Avaliação Educacional , Modelos Educacionais , Fisiologia/educação , Estudantes , Educação em Odontologia/métodos , Avaliação Educacional/métodos , Docentes , Humanos
10.
J Nat Prod ; 71(5): 884-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18407692

RESUMO

High-throughput screening of a plant and marine invertebrate extract library to find natural products with rat thyrotropin releasing hormorne (TRH) receptor 2 binding affinity led to the isolation of four new (1-4) and one known (5) spongian diterpene from the sponge Spongia sp. The structures were assigned from interpretation of 2D NMR and high-resolution ESIMS data. The absolute configurations of 1-4 were proposed on the basis of analysis of their CD spectra. Diterpenes 1-5 showed rat TRH receptor 2 binding affinity with IC(50) values of 23 microM, 70 microM, 400 microM, 600 microM, and 1 mM, respectively.


Assuntos
Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Poríferos/química , Receptores do Hormônio Liberador da Tireotropina/agonistas , Animais , Diterpenos/química , Concentração Inibidora 50 , Estrutura Molecular , Oceanos e Mares , Ratos
11.
J Nat Prod ; 71(5): 881-3, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18412395

RESUMO

High-throughput screeing of a plant and marine invertebrate extract library to find natural products with rat thytotropin releasing hormone receptor 2 binding affinity led to the isolation of two new active acylphloroglucinols, corymbones A and B (1 and 2) from flowers of the Queensland tree Corymbia peltata. Their structures were assigned from interpretation of 2D NMR and high-resolution ESIMS data. Compounds 1 and 2 showed rat TRH receptor 2 binding affinity with IC 50 values of 23 and 19 microM, respectively.


Assuntos
Myrtaceae/química , Floroglucinol/análogos & derivados , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Plantas Medicinais/química , Receptores do Hormônio Liberador da Tireotropina/agonistas , Animais , Flores/química , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/química , Queensland , Ratos
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