Barbara E. Goodman

Insights into digestion and absorption of major nutrients in humans

Nutrient digestion and absorption is necessary for the survival of living organisms and has evolved into the complex and specific task of the gastrointestinal (GI) system. While most people simply assume that their GI tract will work properly to use nutrients, provide energy, and release wastes, few nonscientists know the details about how various nutrients are digested and how the breakdown products traverse the cells lining the small intestine to reach the blood stream and to be used by the other cells of the body. There have been several recent discoveries of new transporters that likely contribute to the absorption of oligopeptides and fatty acids. In addition, details are being clarified about how transporters work and in what forms nutrients can be absorbed. The enzymes that digest basic carbohydrates, proteins, and fats have been identified in various segments of the GI tract, and details are becoming clearer about what types of bonds they hydrolyze. Usually, detailed information about the digestion of basic nutrients is presented and learned in biochemistry courses and detailed information about absorption via transepithelial transport of the breakdown products of digestion is studied in physiology courses. The goal of this Staying Current article is to combine the details of the biochemistry of digestion with the updated information about the physiology of nutrient absorption into one source for teachers of physiology. Insights are included about some of the diseases and conditions that can bring about malabsorption of food in the GI tract and their consequences.

Channels active in the excitability of nerves and skeletal muscles across the neuromuscular junction: basic function and pathophysiology

Ion channels are essential for the basic physiological function of excitable cells such as nerve, skeletal, cardiac, and smooth muscle cells. Mutations in genes that encode ion channels have been identified to cause various diseases and disorders known as channelopathies. An understanding of how individual ion channels are involved in the activation of motoneurons and their corresponding muscle cells is essential for interpreting basic neurophysiology in nerves, the heart, and skeletal and smooth muscle. This review article is intended to clarify how channels work in nerves, neuromuscular junctions, and muscle function and what happens when these channels are defective. Highlighting the human diseases that result from defective ion channels is likely to be interesting to students in helping them choose to learn about channel physiology.

Protein kinase and phosphatase activity in the lungs of normoxic versus hyperoxic rats

Studies were designed to examine aspects of phosphorylation and dephosphorylation in rat lung cells in response to hyperoxic exposure. Protein kinase and phosphatase activities were measured in preparations of lungs from normoxic rats, hyperoxia-exposed rats (95% O2 for 60h), and rats recovering in room air for 1 and 3 days. Protein kinase C (PKC) activity immediately postexposure was significantly lower than in normoxic controls (normoxia 127.1 +/- 13 vs. hyperoxia 101.5 +/- 6 pmol/min mg-1) and continued to decline during the recovery period (85.3 +/- 4 and 78.2 +/- 6 pmol/min mg-1 at 1 and 3 days recovery, respectively). The PKC activity did not translocate from cytoplasm to the membranes. In contrast, PKA activity did not change in response to hyperoxia exposure or recovery. Protein phosphatase activity was decreased significantly by hyperoxia exposure (normoxia 30.7 +/- 3 vs. hyperoxia 21.9 +/- 1 pmol/min microgram-1) but returned to normoxic control levels by 1 and 3 days (24.1 +/- and 31.5 +/- 1 pmol/min microgram -1, respectively). Protein phosphatase activity was inhibited by okadaic acid (Ki = 1 nM) and calyculin A (Ki = 0.61 pM), indicating a type 2A protein phosphatase. Enzyme activities in cultured type II alveolar cells paralleled those observed in whole lung preparations. Decreased enzyme activities in the lung may be located to the development of acute lung injury during hyperoxic exposure.

What is the American Physiological Society's ITL and who are the members of PECOP?

The American Physiological Society Teaching Section has developed a biennial Institute on Teaching and Learning (ITL) through the APS Conference Program. The first ITL was held in June 2014, and the second ITL will be in June 2016. A Physiology Education Community of Practice was created to help connect the institute participants and other physiology educators to share evidence-based teaching in physiology at all education levels and ideas for the Scholarship of Teaching and Learning and Discipline-Based Education Research in physiology. This editorial describes the origins and outcomes of the ITL and the advantages of joining the Physiology Education Community of Practice.

The development and implementation of a new medical biology major including physiology.

In response to the Howard Hughes Medical Institute/Association of American Medical Colleges Scientific Foundations for Future Physicians (SFFP) report and a concern for better preparing undergraduates for future doctoral programs in the health professions, the deans of the College of Arts and Sciences and Division of Basic Biomedical Sciences of Sanford School of Medicine of the University of South Dakota formed an ad hoc Premedical Curriculum Review Committee with representatives from the science departments and medical school. The Committee began by reviewing the universitys suggested premedical curriculum and matching it to the proposed competencies from the SFFP to document duplications and deficiencies. The proposed changes in the Medical College Admission Test for 2015 were also evaluated. The Committee proposed a stronger premedical curriculum, with the development of some new courses, including an inquiry-based physiology course with team-based learning, to more fully address SFFP competencies. These analyses convinced the university that a new major would best help students achieve the competencies and prepare them for admission exams. Thus, a new Medical Biology major was proposed to the South Dakota Board of Regents and accepted for its initial offering in 2012. The new major has been broadly advertised to future students and is successful as a recruiting tool for the university. This article details the process of evaluating the curriculum and designing the new major, describes some of the difficulties in its implementation, and reviews outcomes from the new major to date.

How do the Institutes on Teaching and Learning (ITLs) nurture the members of the Physiology Educators Community of Practice (PECOP)

Do you teach physiology? Do you use best practices when you teach physiology? Have you ever thought about conducting educational research? Do you need collaborators to help with ideas for educational research or to expand your research populations? The American Physiological Society (APS) Teaching Section has developed a biennial Institute on Teaching and Learning (ITL) through the APS Conference Program to address these issues. The first institute was held in June 2014, and the second institute was held in June 2016. A Physiology Education Community of Practice (PECOP) was created to help connect the institute participants and other physiology educators and to share evidence-based teaching in physiology at all education levels. The 2018 APS ITL will be the next meeting to learn best practices, to share ideas with colleagues, and to find collaborators in improving the teaching of physiology for students. The meeting will include workshops modeling best practices, plenary talks about hot new issues in physiology and science education, and poster sessions and informal meals to discuss interests with colleagues. Even if ones primary responsibility is bench research or administration, the training from the institute will improve efficiency and effectiveness when teaching. The two prior ITLs (2014 and 2016) were highly evaluated by educators of both undergraduate and professional students who spent a week together emphasizing improvement in their teaching. This paper reports the outcomes of the 2016 ITL and encourages participation in the upcoming ITL in Madison, WI, June 18-22, 2018. Watch the APS Conference site for more information about the 2018 ITL (http://www.the-aps.org/mm/Conferences/APS-Conferences).

Best practices in active and student-centered learning in physiology classes

This review article includes our analysis of the literature and our own experiences in using various types of active learning as best practices for evidence-based teaching in physiology. We have evaluated what physiology students should be expected to learn and what are specific challenges to enhancing their learning of physiology principles. We also consider how the instructor should design his or her teaching to improve buy-in from both students and other faculty members. We include a discussion of how the readers can evaluate their teaching approaches for their successes in enhancing student learning of physiology. Thus we have addressed pedagogical improvements specific to student learning of physiology, with additional suggestions from cognitive psychology approaches that can improve physiology teaching and learning.