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1.
CBE Life Sci Educ ; 17(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29420183

RESUMO

Evolution is a unifying theory in biology and is challenging for undergraduates to learn. An instructor's ability to help students learn is influenced by pedagogical content knowledge (PCK), which is topic-specific knowledge of teaching and learning. Instructors need PCK for every topic they teach, which is a tremendous body of knowledge to develop alone. However, investigations of undergraduate thinking and learning have produced collective PCK that is available in peer-reviewed literature. Currently, it is unclear whether the collective PCK available adequately addresses the topics in evolution that college instructors teach. We systematically examined existing literature to determine what collective PCK for teaching evolution is available and what is missing. We conducted an exhaustive literature search and analyzed 316 relevant papers to determine: the evolutionary topics addressed; whether the focus was student thinking, assessment, instructional strategies, or goals; and the type of work (e.g., empirical, literature review). We compared the collective PCK available in the literature with the topics taught in a sample of 32 undergraduate evolution courses around the country. On the basis of our findings, we propose priorities for the evolution education research community and propose that PCK is a useful lens for guiding future research on teaching and learning biology.


Assuntos
Evolução Biológica , Biologia/educação , Conhecimento , Ensino , Humanos , Aprendizagem , Revisão da Pesquisa por Pares , Estudantes
2.
CBE Life Sci Educ ; 17(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29420184

RESUMO

Active-learning strategies can improve science, technology, engineering, and mathematics (STEM) undergraduates' abilities to learn fundamental concepts and skills. However, the results instructors achieve vary substantially. One explanation for this is that instructors commonly implement active learning differently than intended. An important factor affecting how instructors implement active learning is knowledge of teaching and learning. We aimed to discover knowledge that is important to effective active learning in large undergraduate courses. We developed a lesson-analysis instrument to elicit teacher knowledge, drawing on the theoretical construct of teacher noticing. We compared the knowledge used by expert (n = 14) and novice (n = 29) active-learning instructors as they analyzed lessons. Experts and novices differed in what they noticed, with experts more commonly considering how instructors hold students accountable, topic-specific student difficulties, whether the instructor elicited and responded to student thinking, and opportunities students had to generate their own ideas and work. Experts were also better able to support their lesson analyses with reasoning. This work provides foundational knowledge for the future design of preparation and support for instructors adopting active learning. Improving teacher knowledge will improve the implementation of active learning, which will be necessary to widely realize the potential benefits of active learning in undergraduate STEM.


Assuntos
Docentes , Conhecimento , Aprendizagem Baseada em Problemas , Humanos , Resolução de Problemas , Estudantes , Ensino , Pensamento
3.
CBE Life Sci Educ ; 15(2)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27174582

RESUMO

Relationships with colleagues have the potential to be a source of support for faculty to make meaningful change in how they teach, but the impact of these relationships is poorly understood. We used a mixed-methods approach to investigate the characteristics of faculty who provide colleagues with teaching resources and facilitate change in teaching, how faculty influence one another. Our exploratory investigation was informed by social network theory and research on the impact of opinion leaders within organizations. We used surveys and interviews to examine collegial interactions about undergraduate teaching in life sciences departments at one research university. Each department included discipline-based education researchers (DBERs). Quantitative and qualitative analyses indicate that DBERs promote changes in teaching to a greater degree than other departmental colleagues. The influence of DBERs derives, at least partly, from a perception that they have unique professional expertise in education. DBERs facilitated change through coteaching, offering ready and approachable access to education research, and providing teaching training and mentoring. Faculty who had participated in a team based-teaching professional development program were also credited with providing more support for teaching than nonparticipants. Further research will be necessary to determine whether these results generalize beyond the studied institution.


Assuntos
Docentes/educação , Pesquisa/educação , Universidades , Humanos , Modelos Lineares , Pesquisadores , Apoio Social
6.
Clin Rheumatol ; 26(8): 1365-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17063282

RESUMO

Behçet's disease (BD) is a chronic relapsing-remitting inflammatory disorder of unknown origin, affecting multiple organs. Neurological involvement is one of the most devastating manifestations of BD and may be fatal. We report a 36-year-old woman with neuro-Behçet who was treated with low-dose pulse cyclophosphamide (St. Thomas' protocol) and methylprednisolone, with almost complete clinical remission.


Assuntos
Síndrome de Behçet/tratamento farmacológico , Ciclofosfamida/administração & dosagem , Imunossupressores/administração & dosagem , Vasculite do Sistema Nervoso Central/tratamento farmacológico , Adulto , Síndrome de Behçet/complicações , População Negra , Feminino , Humanos , Injeções Intravenosas , Indução de Remissão , Vasculite do Sistema Nervoso Central/complicações , Vasculite do Sistema Nervoso Central/etiologia
8.
Am J Med ; 111(3): 185-91, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11530028

RESUMO

PURPOSE: Most patients fail to achieve and maintain low-density lipoprotein (LDL) cholesterol goals established by the National Cholesterol Education Program (NCEP). The Atorvastatin Comparative Cholesterol Efficacy and Safety Study (ACCESS) was a randomized study comparing the efficacy and safety of five statins and their ability reduce LDL cholesterol to the NCEP target level. SUBJECTS AND METHODS: Of 7542 patients screened, 3916 hypercholesterolemic patients were randomly assigned to treatment with a statin, beginning with the lowest recommended dose (atorvastatin, pravastatin, and simvastatin, 10 mg; fluvastatin and lovastatin, 20 mg). If the NCEP target was not achieved, the dose was titrated up to the recommended maximum (atorvastatin, fluvastatin, and lovastatin, 80 mg; pravastatin and simvastatin, 40 mg). The total duration of treatment was 54 weeks. RESULTS: Atorvastatin achieved the greatest mean reduction in LDL cholesterol: 36% +/- 11% at 6 weeks (initial dose) and 42% +/- 13% at 54 weeks. More patients receiving atorvastatin at its initial dose (53%, 997 of 1888) achieved their NCEP target levels than patients receiving simvastatin (38%, 174 of 462), lovastatin (28%, 134 of 472), pravastatin (15%, 71 of 461), or fluvastatin (15%, 69 of 474) at the initial dose. Atorvastatin-treated patients were more likely to maintain their target levels from week 6 to week 54. The percent reduction in LDL cholesterol achieved at the initial dose correlated strongly with the proportion of patients who maintained their goals at 54 weeks (r = -0.84). CONCLUSION: For patients treated with statins, providing a greater margin between the NCEP target level and the achieved LDL cholesterol level enhances the likelihood of maintaining NCEP goal levels.


Assuntos
Anticolesterolemiantes/uso terapêutico , LDL-Colesterol/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Educação de Pacientes como Assunto , Idoso , Atorvastatina , HDL-Colesterol/sangue , Esquema de Medicação , Ácidos Graxos Monoinsaturados/uso terapêutico , Feminino , Fluvastatina , Ácidos Heptanoicos/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Indóis/uso terapêutico , Lovastatina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pravastatina/uso terapêutico , Pirróis/uso terapêutico , Risco , Fatores de Risco , Sinvastatina/uso terapêutico , Resultado do Tratamento , Triglicerídeos/sangue , Estados Unidos
9.
Am J Cardiol ; 88(3): 265-9, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11472705

RESUMO

Apolipoprotein B has been shown to be a better predictor of coronary heart disease than low-density lipoprotein (LDL) cholesterol, and non-high-density lipoprotein (non-HDL) cholesterol may also be a better parameter for coronary heart disease risk assessment and as a target for therapy. Data from the Atorvastatin Comparative Cholesterol Efficacy and Safety Study (ACCESS) were used to assess the correlation between lipid and apolipoprotein B levels before and after lipid-lowering therapy and to examine the effects of 5 hydroxymethylglutaryl coenzyme A reductase inhibitors on lipids and apolipoprotein B. The 54-week study randomized 3,916 hypercholesterolemic patients to atorvastatin, fluvastatin, lovastatin, pravastatin, or simvastatin, initiated at recommended starting doses with titrations as needed at weeks 6, 12, and 18 to achieve National Cholesterol Education Program LDL targets. Compared with LDL cholesterol, non-HDL cholesterol correlated better with apolipoprotein B levels at baseline (r = 0.914, p <0.0001) and at week 54 (r = 0.938, p <0.0001), and the correlation was strong across all baseline triglyceride strata. At starting doses, atorvastatin (10 mg) lowered non-HDL cholesterol by 33.3% compared with 26.6% with simvastatin (10 mg), 24.1% with lovastatin (20 mg), 17.2% with fluvastatin (20 mg), and 17.0% with pravastatin (10 mg). Atorvastatin also provided greater reductions in non-HDL cholesterol after dose titration, and a greater percentage of patients taking atorvastatin achieved non-HDL cholesterol targets. Baseline triglyceride did not affect non-HDL cholesterol reductions with any of the 5 hydroxymethylglutaryl coenzyme A reductase inhibitors. Fewer patients achieved non-HDL cholesterol targets than LDL cholesterol targets, particularly among high-risk patients, implying that if non-HDL cholesterol was used as a target for treatment, more patients would need to be treated more aggressively than National Cholesterol Education Program guidelines require.


Assuntos
Anticolesterolemiantes/uso terapêutico , Colesterol/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Apolipoproteínas B/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Lipídeos/sangue , Fatores de Tempo , Triglicerídeos/sangue
11.
Am J Cardiol ; 87(1): 119-21, A9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11137849

RESUMO

Abnormalities of vascular function occur in patients with risk factors for atherosclerosis before the development of obstructive disease. Our pilot data suggest that elevated serum markers of infection and/or inflammation are associated with functional abnormalities of the vasculature in subjects at otherwise low risk for atherosclerosis.


Assuntos
Anticorpos Antibacterianos/sangue , Proteína C-Reativa/metabolismo , Chlamydophila pneumoniae/imunologia , Endotélio Vascular/fisiologia , Vasodilatação/fisiologia , Adolescente , Adulto , Análise de Variância , Arteriosclerose/etiologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Nitroglicerina , Projetos Piloto , Vasodilatadores
12.
J Pediatr Hematol Oncol ; 23(7): 424-30, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11878576

RESUMO

PURPOSE: To assess cardiovascular risk factors (CVRF) in young adult survivors of childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: Twenty-six subjects (median age, 20.9 years; median interval since completion of therapy, 13.3 years) were evaluated. Ten participants had received cranial irradiation (CRT), whereas 16 had received only chemotherapy. Primary outcome measures included body mass index (BMI), blood pressure, fasting lipoprotein, glucose, and insulin levels. Secondary measures included insulin-like growth factor-1 (IGF-1) and IGF binding protein-3 levels, physical activity index, a 7-day dietary recall, tobacco product use, and measurement of the intima-media thickness (IMT) of the common carotid artery. RESULTS: Sixty-two percent (16/26) of participants had at least one CVRF potentially related to their cancer treatment (obesity, dyslipidemia, increased blood pressure, or insulin resistance), with 30% (7/26) having more than two CVRF. Thirty-one percent (8/26) of subjects were obese (BMI > or = 30). Subjects who were treated with CRT (BMI, 30.4 +/- 6.7) had an increased BMI (P = 0.039) in comparison with those who received only chemotherapy (BMI, 25.4 +/- 5.1). Triglyceride and very low-density lipoprotein C levels were significantly higher in those treated with CRT (P = 0.027 and 0.022, respectively). The IGF-1 was inversely correlated with IMT (total group, -0.514, P = 0.009; females only, -0.729, P = 0.003). CONCLUSIONS: Young adult survivors of childhood ALL, especially those treated with CRT, are at risk for obesity and dyslipidemia, insulin resistance, hypertension, and cardiovascular disease. Further investigation of these risks is warranted.


Assuntos
Doenças Cardiovasculares/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Artéria Carótida Primitiva/patologia , Criança , Pré-Escolar , Terapia Combinada , Irradiação Craniana/efeitos adversos , Feminino , Humanos , Hiperlipidemias/etiologia , Hipertensão/etiologia , Lactente , Masculino , Obesidade/etiologia , Fatores de Risco , Sobreviventes
13.
Curr Atheroscler Rep ; 2(4): 303-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11122758

RESUMO

In healthy individuals, endothelial cells regulate a host of functions including vasomotor tone, thrombosis/ fibrinolysis, and cell-cell interactions. The development of endothelial dysfunction may be a common pathway by which cardiovascular risk factors impact plaque formation, growth, and rupture. Many pharmacologic and nonpharmacologic interventions known to decrease cardiovascular risk also improve endothelial function. For these reasons, some have suggested that improvement in endothelial function may be an important therapeutic target in the treatment of coronary artery disease.


Assuntos
Doença das Coronárias/prevenção & controle , Endotélio Vascular/fisiopatologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Anticolesterolemiantes/uso terapêutico , Circulação Coronária , Doença das Coronárias/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Exercício Físico , Humanos , Lipídeos/sangue , Fatores de Risco , Vasodilatação/fisiologia
14.
Am J Cardiol ; 85(3): 386-7, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11078312

RESUMO

Electron-beam computed tomography is a promising technology for the noninvasive evaluation of patients with suspected coronary artery disease. However, at the present time there is insufficient clinical evidence to support its widespread use as a screening tool for evaluation of patients with chest pain.


Assuntos
Angina Pectoris/etiologia , Doença das Coronárias/diagnóstico , Tomografia Computadorizada por Raios X/normas , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes
15.
Am J Cardiol ; 86(3): 348-50, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10922451

RESUMO

We conducted a prospective randomized study to determine the safety and efficacy rate of 3 commonly used energy levels (100, 200, and 360 J) for elective direct-current cardioversion of persistent atrial fibrillation. When compared with 100 and 200 J, the initial success rate with 360 J was significantly higher (14%, 39%, and 95%, respectively), and patients randomized to 360 J ultimately required less total energy and a lower number of shocks.


Assuntos
Fibrilação Atrial/terapia , Cardioversão Elétrica/métodos , Idoso , Assistência Ambulatorial , Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Prospectivos , Recidiva , Retratamento , Troponina I/sangue
16.
Undersea Hyperb Med ; 27(1): 1-7, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10813433

RESUMO

Rewarming victims of hypothermia such as divers or immersion victims, participants in winter sports and military operations, and surgical patients on cardiopulmonary bypass (CPB) may lead to vascular instability, multiorgan failure, shock, and even death. While the causes of these rewarming symptoms are unknown, they may be related to bacterial lipopolysaccharide (LPS) translocated from the intestines into the circulation due to splanchnic ischemia. We have determined LPS during the cooling (to 31.5 degrees-34.0 degrees C) and rewarming phases of hypothermic surgery in 11 patients at the Stanford University Medical Center. During rewarming, there was an LPS spike in 6/11, in one more patient there was an LPS spike during surgery but not during rewarming, and in 4/11 there was no rise in LPS, i.e., a temporary endotoxemia occurred in 7/11 (63.6%) patients, usually at the commencement of rewarming. All four patients with no LPS spike received dexamethasone for at least 7 days before surgery. We propose that hypothermia reduced splanchnic blood flow (BF), causing ischemic damage to the gut wall and translocation of LPS from the gut into the vascular space. Upon rewarming, splanchnic BF is restored, the translocated LPS transits from the splanchnic to the systemic circulations as a bolus, and the gut wall is healed. No sequelae occurred in these patients because of their adequately functioning immune systems. However, had they been immunocompromised, symptoms might have occurred. Rewarming of accident victims probably also incurs a similar risk of endotoxemia, and dexamethasone may have protected the gut wall. Further studies are indicated.


Assuntos
Hipotermia Induzida , Aneurisma Intracraniano/sangue , Lipopolissacarídeos/sangue , Reaquecimento/efeitos adversos , Temperatura Corporal , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Masculino
17.
J Cogn Neurosci ; 12(1): 142-62, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10769312

RESUMO

Much evidence suggests that lesions of the prefrontal cortex (PFC) produce marked impairments in the ability of subjects to shift cognitive set, as exemplified by performance of the Wisconsin Card Sorting Test (WCST). However, studies with humans and experimental primates have suggested that damage to different regions of PFC induce dissociable impairments in two forms of shift learning implicit in the WCST (that is, extradimensional (ED) shift learning and reversal shift learning), with similar deficits also being apparent after damage to basal ganglia structures, especially the caudate nucleus. In this study, we used the same visual discrimination learning paradigm over multidimensional stimuli, and the H215O positron emission tomography (PET) technique, to examine regional cerebral blood flow (rCBF) changes associated with these subcomponent processes of the WCST. In three conditions, subjects were scanned while acquiring visual discriminations involving either (i) the same stimulus dimension as preceding discriminations (intradimensional (ID) shifts); (ii) different stimulus dimensions from previous discriminations (ED shifts) or (iii) reversed stimulus-reward contingencies (reversal shifts). Additionally, subjects were scanned while responding to already learnt discriminations ('performance baseline'). ED shift learning, relative to ID shift learning, produced activations in prefrontal regions, including left anterior PFC and right dorsolateral PFC (BA 10 and 9⁄46). By contrast, reversal learning, relative to ID shift learning, produced activations of the left caudate nucleus. Additionally, compared to reversal and ID shift learning, ED shift learning was associated with relative deactivations in occipito-temporal pathways (for example, BA 17 and 37). These results confirm that, in the context of visual discrimination learning over multidimensional stimuli, the control of an acquired attentional bias or'set', and the control of previously acquired stimulus-reinforcement associations, activate distinct cortical and subcortical neural stations. Moreover, we propose that the PFC may contribute to the control of attentional-set by modulating attentional processes mediated by occipito-temporal pathways.


Assuntos
Atenção/fisiologia , Córtex Cerebral/fisiologia , Aprendizagem por Discriminação/fisiologia , Adulto , Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Cognição/fisiologia , Humanos , Memória/fisiologia , Testes Neuropsicológicos , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Reversão de Aprendizagem/fisiologia , Recompensa , Tomografia Computadorizada de Emissão
18.
J Neurol Neurosurg Psychiatry ; 68(2): 238-41, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644798

RESUMO

Huntington's disease is characterised by hyperkinetic movements, mainly chorea, cognitive dysfunction, and psychiatric abnormalities. Non-dopa responsive parkinsonism occurs in the later stages of choreic disease or as the predominant feature of juvenile patients (Westphal variant). Late onset Huntington's disease presenting as levodopa responsive parkinsonism is rare. A series of four patients with late onset Huntington's disease presenting as levodopa responsive parkinsonism and cardiovascular dysautonomia, initially misdiagnosed as multiple system atrophy (MSA) in three patients, is reported. Levodopa treatment did not unmask significant chorea. These cases suggest the presence of a distinct phenotypic variant of Huntington's disease to be added to the differential diagnosis of other akinetic rigid syndromes.


Assuntos
Antiparkinsonianos/uso terapêutico , Coreia/diagnóstico , Doença de Huntington/diagnóstico , Doença de Huntington/tratamento farmacológico , Levodopa/uso terapêutico , Doença de Parkinson/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Doença de Huntington/genética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão , Resultado do Tratamento , Repetições de Trinucleotídeos
19.
Brain ; 122 ( Pt 12): 2353-63, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10581228

RESUMO

Using serial [(11)C]SCH 23390- and [11C]raclopride-PET, we have measured the rate of loss of striatal dopamine D1 and D2 receptor binding over a mean of 40 months in nine asymptomatic adult Huntington's disease mutation carriers, four patients with symptomatic disease, seven mutation-negative controls and three subjects at risk for the disease. Eight of the nine asymptomatic Huntington's disease mutation carriers had serial [11C]raclopride-PET and showed a mean annual loss of striatal D2 binding of 4.0%. Only five of these eight, however, showed active progression, and they had a mean annual loss of D2 binding of 6.5%. All nine asymptomatic mutation carriers had serial [11C]SCH 23390-PET and showed a mean annual loss of striatal D1 binding of 2. 0%. Four of these subjects demonstrated active progression and they had a mean annual loss of 4.5%. Our four symptomatic Huntington's disease patients showed a mean annual loss of D2 binding of 3.0% and of D1 binding of 5.0%. Loss of striatal D1 and D2 binding was significantly greater in the known mutation carriers than in the combined at-risk and gene-negative groups (P < 0.05). At follow-up PET all subjects were clinically assessed using the Unified Huntington's Disease Rating Scale. Scores for motor function and total functional capacity correlated with PET measures of striatal dopamine receptor binding both in the asymptomatic mutation carriers (D1, P < 0.01) and across the combined asymptomatic and clinically affected Huntington's disease mutation carrier group (D1 and D2, P < 0.001). We conclude that PET measures of striatal D1 and D2 dopamine binding can be used to identify asymptomatic Huntington's disease mutation carriers who are actively progressing and who would thus be suitable for putative neuroprotective therapies. Measures of disease progression rates in Huntington's disease patients and asymptomatic mutation carriers will be of critical importance in future trials of experimental restorative treatments.


Assuntos
Corpo Estriado/metabolismo , Doença de Huntington/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Adulto , Idoso , Benzazepinas/metabolismo , Corpo Estriado/diagnóstico por imagem , Progressão da Doença , Antagonistas de Dopamina/metabolismo , Feminino , Humanos , Doença de Huntington/genética , Doença de Huntington/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Racloprida/metabolismo , Estudos Retrospectivos , Tomografia Computadorizada de Emissão
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