Charlotte A. Otto

Development and Evaluation of an Inquiry-Based Elementary Science Teacher Education Program Reflecting Current Reform Movements.

The National Science Education Standards (National Research Council 1996, National science education standards. Washington, DC: National Academy Press) and various other national and state documents call for teachers who possess science content knowledge, employ an inquiry approach in teaching, and engage in reflective practices. This paper describes a rationale for choosing particular recommendations to implement and how we incorporated those as we revised our elementary science education program. An analysis of the impact of the reformed inquiry-based content courses revealed that students who take more than one reformed content course improve their science content knowledge and efficacy towards teaching science significantly more than students who take fewer courses.

In Vitro and Ex Vivo Evaluation of Cyclic Aminoalkyl Benzilates as Potential Emission Tomography Ligands for the Muscarinic Receptor

A series of muscarinic antagonists were screened as potential receptor imaging agents. (+)2 alpha-tropanyl benzilate (TRB), N-methyl-4-piperidyl benzilate (NMPB) and several analogs amenable to labeling with positron emitting isotopes were evaluated for muscarinic binding to mouse brain tissue in vitro and ex vivo using [3H]quinuclidinyl benzilate as the probe. The in vitro assay directly compared the innate binding affinities of the compounds. The rank order of binding (IC50) was TRB (0.7 nm), QNB (0.8 nm), scopolamine (1.3 nm) and NMPB (1.6 nm). The ex vivo assay was used to gain information regarding the pharmacokinetics and brain penetration of the compounds in live animals. Ex vivo results demonstrated that TRB was rapidly taken up into the brain and was equipotent with QNB in occupying muscarinic binding sites at early time points, but TRB binding decreased twice as fast over time as QNB binding. The results suggest TRB would be a good candidate for radiolabeling and further study.

An Instructional Strategy to Introduce Pedagogical Content Knowledge Using Venn Diagrams

This paper describes the use of a three-circle Venn diagram as a vehicle for introducing pre-service elementary teachers to pedagogical content knowledge (PCK). Each circle of the diagram represents pedagogy, content and context individually. The overlap of any two circles represents the interaction between the circles. For example, the overlap of pedagogy and context relates to the ways that each of these general topics influences the other. The overlap of all three circles represents a complete lesson that is an integration of the three major components of PCK. The Venn diagram is an easily remembered graphic illustration of PCK that can be useful in planning lessons. The use of this graphic organizer in a science capstone course required of all pre-service elementary teachers is described.

An Innovative Course Featuring Action Research Integrated with Unifying Science Themes

In this article, we describe an innovative capstone course for preservice K-8 teachers integrating action research and a unifying theme in science (AAAS in Science for all Americans. Oxford University Press, New York, 1989; NRC in National science education standards. National Academy Press, Washington, DC, 1996). The goals of the capstone course are to increase student knowledge of the unifying theme, improve written communication skills, and introduce students to educational research. We provide evidence that each of these goals is met. Student growth in theme knowledge is demonstrated through concept maps, questionnaires, and previously reported assessments. Improved writing ability is demonstrated using the spelling and grammar checking feature of Microsoft Word. The analysis of action research reports demonstrates that students are able to connect their action research project results to previous research.

ω-iodophenyl fatty acids: A convenient method of radioiodination

A solid-phase radioiodination technique for omega-iodophenyl fatty acids using ammonium sulfate is described. The radioiodinations are regioselective, high in yield (95%), short in reaction time (1 h) and capable of yielding high specific activity products although at lower yields. Purification is exceptionally simple: a single passage through an ion exchange column to remove unreacted I- is all that is required. Syntheses of several omega-iodophenyl fatty acids are also described.

Subcellular distribution of [125I]iodoaryl beta-methyl fatty acids.

Subcellular distribution studies of two aryl branched-chain and one aryl straight-chain iodinated fatty acids were carried out as part of a continuing effort to determine if such acids are metabolized by beta-oxidation. For the omega-iodoaryl fatty acids, a change in subcellular radioactivity location was observed which was chain-length dependent. Chain lengths of 15 carbons, straight and branched, were largely found in the nuclear-membrane fraction, whereas a chain length of 8 carbons was largely located in the cytosol. No unequivocal evidence for metabolic trapping in the mitochondria was observed for omega-iodoaryl branched-chain fatty acids using the centrifugation technique employed in this study.

Use of DES-treated rats as an animal model for assessment of pituitary adenoma imaging agents

Prolactin (PRL) secreting pituitary adenomas are the most common type of pituitary tumors. An imaging agent which specifically localized in prolactinomas would be of considerable clinical value for both initial detection and also for monitoring the effects of dopamine agonist therapy. Tritiated spiroperidol (3HSp) was selected for initial evaluation as a possible imaging agent based on: demonstrated localization in the pituitary and demonstrated binding to human PRL-secreting tumor tissue. DES was implanted in Fischer F344 rats and induced prolactinoma formation was evidenced by increased pituitary weight, elevated serum PRL levels and by an increase in the proportion of PRL-secreting cells in the pituitary. 3HSp concentrations in pituitary and other tissues of DES-treated rats were assessed in female rats and correlation studies showed that a 5-fold increase in serum PRL was associated with a 6-fold increase in both pituitary weight and % dose/organ accumulation of 3HSp. The number of pituitary D2 receptors per mg of protein in tissue homogenates was similar in both normal and DES-treated females. A blocking study with (+)-butaclamol demonstrated a D2 receptor-mediated component to 3HSp localization. In summary, an animal model for prolactinoma was characterized. An assessment of 3HSp accumulation indicates that radiolabelled spiroperidol shows excellent potential for detecting PRL-secreting tumors of the pituitary.

Pituitary localization of 3H-spiroperidol by an uptake/storage mechanism?

The lack of a pituitary imaging agent combined with the considerable clinical value for such an agent prompted an examination of 3H-spiroperidol (3HSp). Spiroperidol was selected for initial evaluation based on its high affinity for D2 receptors which are known to be present in the pituitary. A time course study of 3HSp concentration in rat pituitary and other tissues was conducted. Pituitary activity levels were found to be constant from 5 min to 4 h and were about 8 times levels in corpus striatum at 1 h. Blocking studies with (+) butaclamol and with unlabelled spiroperidol suggested the existence of both a D2 receptor mediated binding localization and a second uptake which is postulated to be an internalization process. Further studies involving ultracentrifugation of pituitary homogenates resulted in evidence for association of 3HSp with dense subcellular particles. 3HSp thus appears to be internalized by pituitary cells.

Drawings as a Component of Triangulated Assessment.

Action research (AR) in an educational setting as described by Tillotson (2000) is an approach to “classroom-based problems” or “specific school issues” (p. 31). His process involves identification of the issue or problem, development and implementation of an action plan, gathering and interpreting data, sharing the results within the community, and “action planning” as a cyclical endeavor (Tillotson, 2000, p. 32). AR is utilized as a key component of developing pre-service teachers in the University of Michigan-Dearborn certification program. Illustrating the five components of Tillotson’s approach, pre-service elementary teachers develop and analyze pre-assessments of K-8 student knowledge about a specific science topic to identify prior student understanding; they create and teach two lessons to provide applicable scientific content, post-assess to determine the impact of their teaching and write a research journal style report describing their project. The AR assignment is more structured than a typical action research project in order to support the pre-service teachers, many whom have never conducted a literature review, created assessments linked to research, or completed an AR project (Luera & Otto, 2005).

Evaluation of Quaternized and Neutral Muscarinic Receptor Ligands in Normal and DES-treated Rat

The localization of quaternized muscarinic receptor (mAChR) antagonists, [11C]methyl tropanyl benzilate ([11C]MTRB) and [11C]methyl quinuclidinyl benzilate ([11C]MQNB), in rat pituitary was compared to that of [11C]tropanyl benzilate ([11C]TRB), a neutral antagonist. The quaternized ligands localize via a mAChR-mediated mechanism as shown by 60% reduction in radioactivity concentrations in the presence of QNB. [11C]TRB appears to localize primarily by a non-mAChR specific mechanism. Induction of pituitary prolactinomas by diethylstilbestrol resulted in a reduction of [11C]MTRB pituitary localization compared to normals. Elevated serum prolactin levels due to prolactinoma presence had no measurable effect on myocardial [11C]MTRB uptake or on KD values. Bmax values for myocardial mAChR were similar for controls and for DES exposure of 10 weeks.