BUILDing BLaST: promoting rural students' biomedical research careers using a culturally responsive, one health approach.

BACKGROUND AND PURPOSE: Most postsecondary institutions in the state of Alaska (USA) have a broad mission to serve diverse students, many of whom come from schools in rural villages that are accessible only by plane, boat, or snowmobile. The major research university, the University of Alaska in Fairbanks (UAF), serves a population whereby 40% are from groups recognized as underrepresented in the biomedical workforce. The purpose of this article is to describe the Building Infrastructure Leading to Diversity (BUILD)-supported program in the state of Alaska that seeks to engage students from rural areas with a culturally relevant approach that is centered on the One Health paradigm, integrating human, animal, and environmental health. PROGRAM AND KEY HIGHLIGHTS: The Biomedical Learning and Student Training (BLaST) program distinguished by broad themes that address recruitment, retention, and success of students in biomedical programs, especially for students from rural backgrounds. Targeted rural outreach emphasizes that biomedical research includes research on the integration of human, animal, and environmental health. This One Health perspective gives personal relevance and connection to biomedical research. This outreach is expected to benefit student recruitment, as well as foster family and community support for pursuit of college degrees. BLaST promotes integration of research into undergraduate curricula through curriculum development, and by creating a new class of instructors, laboratory research and teaching technicians, who provide research mentorship, course instruction, and comprehensive advising. Finally, BLaST facilitates early and sustained undergraduate research experiences in collaborations with graduate students and faculty. IMPLICATIONS: BLaST's approach is highly adapted to the Alaskan educational and physical environment, but components and concepts could be adapted to other rural areas as a means to engage students from rural backgrounds, who often have a closer relationship with the natural environment than urban students.

Designing fish for improved human health status.

The time-course of accumulation of dietary organic and inorganic selenium (Se; 1.5 mg Se kg(-1) dry weight feed) was examined for muscle and hepatic tissues of hybrid striped bass (HSB) over 6 weeks. Animals, which had been fed a Se deficient diet for 2 months prior to study, were maintained in a recirculating life support system at 28 +/- 1 degrees C. PIT tagged fish were randomly assigned to one of 24 120 L aquaria (n = 5 per tank) and subsequently fed one of four diets: a fishmeal-based diet (control), soybean-casein-based feeds either supplemented with organic (SelPlex) or inorganic (sodium selenite) Se or as a basal diet, purposefully deficient in Se. Fish were fed twice daily on a 4% body weight basis. Samples taken at trial start (week 0), mid-way (3 weeks) and at trial end (6 weeks) included weight and length data, hepatosomatic (HSI) and visceral (VSI) indices, intraperitoneal fat (IPF) and muscle (MR) and feed conversion (FCR) ratios, serum protein (SP), hematocrit (PCV), and serum glutathione peroxidase (GP(x)) activity and muscle and heaptic Se concentrations. Survival was also monitored throughout the study. Muscle and hepatic Se levels increased in fishmeal and Se supplemented diets throughout the study. At trail end, greatest weight gain (P < 0.05) was observed in fish fed the control, fishmeal-based diet. Comparison of tissue Se levels indicated that the liver accumulated this mineral at greater concentrations than the muscle with highest levels being observed in the inorganic Se fed fish (P < 0.05). Se accumulation in control and inorganic Se fed fish was similar, whilst Se in the liver of fish fed the Se deficient diet was lowest among groups (P < 0.05). Muscle Se accumulation was found to be greatest in organic Se containing diets (P < 0.05), whereas the basal, Se deficient diet group, returned lowest levels (P < 0.05). Plasma GP(x) activity was similar in HSB fed the fishmeal and organic Se diets. The fishmeal fed group expressed higher (P < 0.05) GP(x) levels than that recorded for either the inorganic or basal diets. At trial end, no differences were recorded between groups for PCV or HSI, VSI or IPF. SP levels and MR were higher (P < 0.05) in fishmeal control fed fish. FCRs were lowest in fishmeal fed fish and highest for the Se deficient or basal diet. These studies demonstrate the feasibility of producing cultured fish with heightened levels of Se using simple dietary manipulations for 4-6 weeks or less before harvesting.

Cardiac hemodynamics of the rainbow trout (Oncorhynchus mykiss) using simultaneous Doppler echocardiography and electrocardiography.

Using Doppler echocardiography and electrocardiography, we characterized cardiac hemodynamics, timing, and electromechanical function, and examined the effects of ventricular hypertrophy on systolic function in anesthetized rainbow trout. Atrial filling (D(SA)), ventricular filling (D(AV)), and ventricular ejection (D(VB)) accounted for 40-77, 13-27, and 22-41% of the cardiac cycle, respectively. Ventricular ejection occurred entirely during atrial filling and ended by the time the QT interval was 80% (SD=9%) completed. Sinoatrial (SA) flow was of longer duration (0.53+/-0.08 sec, mean+/-SD) and lower velocity (32+/-8 cm sec(-1)) than corresponding atrioventricular (AV, 0.19+/-0.02 sec; 87+/-8 cm sec(-1)) and ventriculobulbar (VB, 0.30+/-0.05 sec; 63+/-20 cm sec(-1)) values. Despite a wide range of heart masses, atrioventricular and VB valve dimensions were identical ( approximately 5.5 mm(2)). Ventricle mass (M(V)), but not relative ventricle mass (RVM), and cardiac cycle length were positively correlated (r(2)=0.57, P<0.001); thus, all time-dependent electrical/mechanical measures of cardiac function were significantly related to M(V), but not RVM. All rate-corrected (c) electromechanical event durations (except cD(SA)) and the systolic function index (cPEP (pre-ejection period)/D(VB)) were independent of RVM, suggesting the maintenance of cardiac functional capabilities across maturation stages (males) and different ventricle sizes (males and females). In summary, we define fundamental electrical and mechanical properties of the in vivo teleost myocardium under anesthesia, and report the maintenance of systolic function over a wide range of heart sizes for both sexes and maturation state of males. We also suggest that the short duration of ventricular emptying relative to the QT interval may provide a novel mechanism to adjust stroke volume and cardiac output in teleosts.

Fishing for an ECG: a student-directed electrocardiographic laboratory using rainbow trout.

Cardiac physiology is emphasized in many undergraduate physiology courses, but few nonmammalian vertebrate model systems exist that 1) can be studied fairly noninvasively, 2) are well suited for controlled experimentation, and 3) emphasize principles characteristic of the vertebrate heart. We have developed an inquiry-based undergraduate/graduate-level laboratory in cardiac physiology and electrocardiography using rainbow trout (Oncorhynchus mykiss Walbaum) and the BioPac MP30 data-acquisition system (other fish species and/or electrocardiographic recording devices can be substituted). This laboratory facilitates intensive study of vertebrate electrocardiograms (ECGs) under a variety of environmental and physiological perturbations and is ideal for use in multi-session, inquiry-based laboratory projects in animal physiology. Furthermore, students gain valuable experience in scientific inquiry, study design, following and/or developing scientific protocols, and animal care. This laboratory requires the ability to keep captive fish of at least 100 g and equipment to record ECGs. Departments meeting these requirements can adopt this technique at modest expense. Student enthusiasm and feedback were positive, and several students commented that the nonlethal methods used added to the laboratory's perceived value.

Vasoconstrictor response to topical beclomethasone in major depression.

Overactivity of the hypothalamic-pituitary-adrenal (HPA) axis has been frequently described in depression. Due to the closed-loop nature of the HPA axis, one possible cause of this overactivity may be a defect in negative feedback regulation, in particular an abnormality of the glucocorticoid receptor (GR). In the present study, the vasoconstrictor response to the topical glucocorticoid, beclomethasone, was used to examine GR function in depression. Topical beclomethasone was applied in four concentrations (10 microl each of 3, 10, 30 and 100 microg/ml) to the forearms of 22 subjects with major depression and their age- and sex-matched controls. Skin blanching responses were compared between the depressed and control groups and, within the depressed group, on the basis of the modified dexamethasone suppression test (DST), between cortisol suppressors and non-suppressors. Depressed subjects demonstrated a significantly reduced vasoconstrictor response compared to controls (P=0.0001). No difference was detected between cortisol suppressors and non-suppressors in their skin blanching responses. These findings suggest that peripheral GR function is abnormal in depression but that the reduced vasoconstrictor response to beclomethasone is not necessarily a secondary effect of hypercortisolaemia or HPA axis overactivity.