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Idaho Institutional Development Award (IDeA) Network for Biomedical Research Excellence (INBRE) aims to build biomedical research capacity and enhance the scientific and technology knowledge of the Idaho workforce. A key INBRE Program at The College of Idaho, a primarily undergraduate institution of 1,100 students, is a 10-wk summer fellows research experience. This report documents outcomes from 2005 to present, including demographic trends, faculty and student research productivity, self-reported gains, educational attainment, and career outcomes. Of 103 participants, 83.7% were from Idaho, 26.7% from rural areas, and 23.9% first-generation college students. Faculty and student research productivity (conference presentations and peer-reviewed publications) increased threefold. We found that 91.4% of fellows entered a scientific- or healthcare-related career and that 70.7% completed or are currently enrolled in postgraduate training (51.7% doctoral and 19.0% master's level). Anonymous surveys were uniformly positive, with gains in self-confidence and independent laboratory work. Open-ended responses indicated students valued mentoring efforts and improved awareness of scientific opportunities and competitive preparation for postgraduate training. Lastly, we observed that student research involvement increased college-wide during the award period. These data suggest that the summer fellows program is successfully meeting National Institutes of Health IDeA goals and serving as a pipeline to future health research careers and a scientifically trained Idaho workforce.

Background: The tumor-derived GL261 cell line is used as a model for studying glioblastoma and other high-grade gliomas, and can be cultured adherently or as free-floating aggregates known as neurospheres. These different culture conditions give rise to distinct phenotypes, with increased tumorigenicity displayed by neurosphere-cultured cells. An important technique for understanding GL261 pathobiology is live cell fluorescent imaging of intracellular calcium. However, live cell imaging of GL261 neurospheres presents a technical challenge, as experimental manipulations where drugs are added to the extracellular media cause the cells to move during analysis. Here we present a method to immobilize GL261 neurospheres with low melting point agarose for calcium imaging using the fluorescent calcium sensor fura-2., Methods: GL261 cells were obtained from the NCI-Frederick Cancer Research Tumor Repository and cultured as adherent cells or induced to form neurospheres by placing freshly trypsinized cells into serum-free media containing fibroblast growth factor 2, epidermal growth factor, and B-27 supplement. Prior to experiments, adherent cells were loaded with fura-2 and cultured on 8-well chamber slides. Non-adherent neurospheres were first loaded with fura-2, placed in droplets onto an 8-well chamber slide, and finally covered with a thin layer of low melting point agarose to immobilize the cells. Ratiometric pseudocolored images were obtained during treatment with ATP, capsaicin, or vehicle control. Cells were marked as responsive if fluorescence levels increased more than 30% above baseline. Differences between treatment groups were tested using Student's t-tests and one-way ANOVA., Results: We found that cellular responses to pharmacological treatments differ based on cellular phenotype. Adherent cells and neurospheres both responded to ATP with a rise in intracellular calcium. Notably, capsaicin treatment led to robust responses in GL261 neurospheres but not adherent cells., Conclusions: We demonstrate the use of low melting point agarose for immobilizing GL261 cells, a method that is broadly applicable to any cell type cultured in suspension, including acutely trypsinized cells and primary tumor cells. Our results indicate that it is important to consider GL261 phenotype (adherent or neurosphere) when interpreting data regarding physiological responses to experimental compounds.

Mycobacteriophages--viruses of mycobacterial hosts--are genetically diverse but morphologically are all classified in the Caudovirales with double-stranded DNA and tails. We describe here a group of five closely related mycobacteriophages--Corndog, Catdawg, Dylan, Firecracker, and YungJamal--designated as Cluster O with long flexible tails but with unusual prolate capsids. Proteomic analysis of phage Corndog particles, Catdawg particles, and Corndog-infected cells confirms expression of half of the predicted gene products and indicates a non-canonical mechanism for translation of the Corndog tape measure protein. Bioinformatic analysis identifies 8-9 strongly predicted SigA promoters and all five Cluster O genomes contain more than 30 copies of a 17 bp repeat sequence with dyad symmetry located throughout the genomes. Comparison of the Cluster O phages provides insights into phage genome evolution including the processes of gene flux by horizontal genetic exchange.

TRPM8 (Transient Receptor Potential Melastatin-8) is a cold- and menthol-gated ion channel necessary for the detection of cold temperatures in the mammalian peripheral nervous system. Functioning TRPM8 channels are required for behavioral responses to innocuous cool, noxious cold, injury-evoked cold hypersensitivity, cooling-mediated analgesia, and thermoregulation. Because of these various roles, the ability to pharmacologically manipulate TRPM8 function to alter the excitability of cold-sensing neurons may have broad impact clinically. Here we examined a novel compound, PBMC (1-phenylethyl-4-(benzyloxy)-3-methoxybenzyl(2-aminoethyl)carbamate) which robustly and selectively inhibited TRPM8 channels in vitro with sub-nanomolar affinity, as determined by calcium microfluorimetry and electrophysiology. The actions of PBMC were selective for TRPM8, with no functional effects observed for the sensory ion channels TRPV1 and TRPA1. PBMC altered TRPM8 gating by shifting the voltage-dependence of menthol-evoked currents towards positive membrane potentials. When administered systemically to mice, PBMC treatment produced a dose-dependent hypothermia in wildtype animals while TRPM8-knockout mice remained unaffected. This hypothermic response was reduced at lower doses, whereas responses to evaporative cooling were still significantly attenuated. Lastly, systemic PBMC also diminished cold hypersensitivity in inflammatory and nerve-injury pain models, but was ineffective against oxaliplatin-induced neuropathic cold hypersensitivity, despite our findings that TRPM8 is required for the cold-related symptoms of this pathology. Thus PBMC is an attractive compound that serves as a template for the formulation of highly specific and potent TRPM8 antagonists that will have utility both in vitro and in vivo.

Behavioral assays in the undergraduate neuroscience laboratory are useful for illustrating a variety of physiological concepts. An example is homeostatic temperature regulation (thermoregulation). Many model organisms, from flies to mice, regulate internal temperatures in part by moving to suitable climates (thermotaxis). A particularly reliable method of quantifying temperature-dependent thermotactic behaviors is the two-temperature preference behavioral assay. In this preparation, an organism is free to move between two temperature-controlled surfaces, thus revealing its preferred thermal environment. Here we present the design and construction of a two-temperature preference assay chamber. The device uses Peltier-based thermoelectric modules (TECs) for heating and cooling, and is capable of precision control of temperatures from -5ºC to 60ºC. Our approach can be easily adapted for use in a variety of physiological and behavioral assays that require precise temperature control over a wide range of temperatures.

Numerous cases of urate nephrolithiasis in managed collections of common bottlenose dolphins (Tursiops truncatus) have been reported, but nephrolithiasis is believed to be uncommon in wild dolphins. Risk factors for urate nephrolithiasis in humans include low urinary pH and hypocitraturia. Urine samples from 94 dolphins were collected during April 2006 through June 2009 from 4 wild populations (n = 62) and 4 managed collections (n = 32). In addition, urine uric acid and pH were tested in a subset of these animals. Our null hypothesis was that wild and managed collection dolphins would have no significant differences in urinary creatinine, citrate, and uric acid concentrations and pH. Among urine samples from all 94 dolphins, the urinary levels (mean +/- SEM) for creatinine, citrate, uric acid, and pH were 139 +/- 7.6 mg/dL, 100 +/- 20 mg citrate/g creatinine, 305 +/- 32 mg uric acid/g creatinine, and 6.2 +/- 0.05, respectively. Of the 4 urinary variables, only citrate concentration varied significantly between the 2 primary study groups; compared with wild dolphins, managed collection dolphins were more likely to have undetectable levels of citrate in the urine (21.0% and 81.3%, respectively). Mean urinary citrate concentrations for managed collection and wild dolphin populations were 2 and 150 mg citrate/g creatinine, respectively. We conclude that some managed collections of dolphins, like humans, may be predisposed to urate nephrolithiasis due to the presence of hypocitraturia. Subsequent investigations can include associations between metabolic syndrome, hypocitraturia, and urate nephrolithiasis in humans and dolphins; and the impact of varying levels of seawater ingestion on citrate excretion.

The occurrence of trace levels of prescription and over-the-counter pharmaceuticals in the environment began to receive concerted attention nearly two decades ago. The public's growing awareness and concern over the presence of these chemicals, especially in drinking water, has served to catalyze considerable discussion and debate regarding the best practices for disposal of unused or unwanted medications. In the United States, the first federal guidance for consumers was issued in 2007. It recommends discarding unused pharmaceuticals to household trash, after taking precautions to mix the pharmaceuticals with an inert substance and conceal the contents from view. Providing the consumer with additional options for conscientious disposal are various community, city, and state collection events, ongoing programs, and government-funded pilot projects. These strategies include the opportunity to mail or bring unused medications to various collection points, such as pharmacies, for eventual destruction. All of these approaches to medication disposal play roles in reducing the introduction of pharmaceuticals to the environment.

Cold temperatures robustly activate a small cohort of somatosensory nerves, yet during a prolonged cold stimulus their activity will decrease, or adapt, over time. This process allows for the discrimination of subtle changes in temperature. At the molecular level, cold is detected by transient receptor potential melastatin 8 (TRPM8), a nonselective cation channel expressed on a subset of peripheral afferent fibers. We and others have reported that TRPM8 channels also adapt in a calcium-dependent manner when activated by the cooling compound menthol. Additionally, TRPM8 activity is sensitive to the phospholipid phosphoinositol 4,5-bisphosphate (PIP2), a substrate for the enzyme phospholipase C (PLC). These results suggest an adaptation model whereby TRPM8-mediated Ca2+ influx activates PLC, thereby decreasing PIP2 levels and resulting in reduced TRPM8 activity. Here we tested this model using pharmacological activation of PLC and by manipulating PIP2 levels independent of both PLC and Ca2+. PLC activation leads to adaptation-like reductions in cold- or menthol-evoked TRPM8 currents in both heterologous and native cells. Moreover, PLC-independent reductions in PIP2 had a similar effect on cold- and menthol-evoked currents. Mechanistically, either form of adaptation does not alter temperature sensitivity of TRPM8 but does lead to a change in channel gating. Our results show that adaptation is a shift in voltage dependence toward more positive potentials, reversing the trend toward negative potentials caused by agonist. These data suggest that PLC activity not only mediates adaptation to thermal stimuli, but likely underlies a more general mechanism that establishes the temperature sensitivity of somatosensory neurons.

Sensory nerves detect an extensive array of somatosensory stimuli, including environmental temperatures. Despite activating only a small cohort of sensory neurons, cold temperatures generate a variety of distinct sensations that range from pleasantly cool to painfully aching, prickling, and burning. Psychophysical and functional data show that cold responses are mediated by both C- and A delta-fibers with separate peripheral receptive zones, each of which likely provides one or more of these distinct cold sensations. With this diversity in the neural basis for cold, it is remarkable that the majority of cold responses in vivo are dependent on the cold and menthol receptor transient receptor potential melastatin 8 (TRPM8). TRPM8-null mice are deficient in temperature discrimination, detection of noxious cold temperatures, injury-evoked hypersensitivity to cold, and nocifensive responses to cooling compounds. To determine how TRPM8 plays such a critical yet diverse role in cold signaling, we generated mice expressing a genetically encoded axonal tracer in TRPM8 neurons. Based on tracer expression, we show that TRPM8 neurons bear the neurochemical hallmarks of both C- and A delta-fibers, and presumptive nociceptors and non-nociceptors. More strikingly, TRPM8 axons diffusely innervate the skin and oral cavity, terminating in peripheral zones that contain nerve endings mediating distinct perceptions of innocuous cool, noxious cold, and first- and second-cold pain. These results further demonstrate that the peripheral neural circuitry of cold sensing is cellularly and anatomically complex, yet suggests that cold fibers, caused by the diverse neuronal context of TRPM8 expression, use a single molecular sensor to convey a wide range of cold sensations.

Detection of innocuous temperatures allows an organism to select an appropriate environmental climate, while the ability to recognize noxious temperature extremes warns of impending tissue damage. For temperatures considered cold, the menthol receptor TRPM8 is activated when temperatures drop below approximately 26 degrees C, thus making it an intriguing candidate as the molecular mediator of cold perception. However, confirmation of this hypothesis in vivo has eluded researchers until recently. Three independent research groups have reported that mice lacking this single gene are severely impaired in their ability to detect cold temperatures. Remarkably, these animals are deficient in many diverse aspects of cold signaling, including cool and noxious cold perception, injury-evoked sensitization to cold, and cooling-induced analgesia. These animals provide a great deal of insight into the molecular signaling pathways that participate in the detection of cold and painful stimuli.

Previous studies have shown that viral upper respiratory tract (URT) infection predisposes to the development of bacterial otitis media (OM). The mechanisms underlying this phenomenon have been well defined for influenza A virus in the chinchilla model of experimental OM but have not been for adenovirus because of the heretofore lack of an appropriate model. In this study, chinchillas were inoculated intranasally or transbullarly with type 1 adenovirus to assess whether or not the chinchilla could serve as a suitable model for future investigation of adenovirus predisposition to bacterial OM. Data indicated that the chinchilla readily supported an active infection by and responded serologically to this agent and that route of inoculation markedly influenced otoscopic findings, elicitation of middle ear fluids, onset and location of histopathology, and progression of disease. The time course of disease onset and recovery and an assessment of the effect of this virus isolate on the mucosal epithelial integrity and on both the ciliary activity and transport function of the eustachian tube epithelium for both routes of inoculation are presented.