Important Conclusions

Determined a positive correlation between excretion (a physiological response) and preferred ambient temperature (a behavioral response). Rats injected with icilin (TRPM8 agonist), a drug that produces a cooling sensation, were shown to both excrete more in the warmer regions of the thermogradient and position themselves more in the warmer region of the thermogradient. Likewise, rats injected with GSK (TPV4 agonist), a drug that produces a warming sensation, exhibited the converse. Rats injected with vehicle, a control drug, showed no apparent preference. TRPM8 is a gene in the brain that is known as the "receptor for cold and menthol." Likewise, TPV4 is known to induce hypersensitivity.

Concluded that rats with lesions do not exhibit the "wet dog shaking" behavior when injected with icilin, while rats without lesions exhibit this behavior. We purposefully lesioned the area of the hypothalamus (of the brain), where wet dog shakes have been empirically shown to originate from. Chart below displays the average number of shakes per rat in a ten-minute period.

Week Ten

This week, I will be completing and finalizing data analysis (for our on-site experiment) and data calculations (for our off-site experiment).

For our on-site experiment, I am analyzing results from our behavioral studies of stress levels. Specifically, I am trying to determine if there is a correlation between the behavioral aspect of stress and preferred ambient temperature and the physiological response of excretion and shivering. I am conducting statistical tests to see if there is a significance in our results comparing the shivering response. 

From our retrospective clinical study, I am continuing to calculate wet bulb globe temperatures. This study has been in process for about a year. I joined the study in about fall of 2015. However, we have had setbacks, which I have mentioned in previous blog posts, such as calculating wet bulb temperature instead and having inaccurate or missing GPS coordinates. Therefore, I do not expect to finish by the official conclusion of my Senior Research Project. I will continue with the study beyond my official Senior Research Project timeline.

Week Nine

This week, I will be managing around the laboratory, as well as conduct data analysis (for our on-site experiment) and data calculations (for our off-site experiment).

On-Site Experimentation: 

Surgeries and experimentation take place as normal again this week. I will continue to clean the thermogradient and ensure that all laboratory equipment is cleaned and sterilized. I am organizing our data and currently, I am specifically focusing on finding a correlation between stress levels and preferred ambient temperature.

Retrospective Clinical Study:

I am continuing to do data collections. As of this week, I am focusing on recording data from Arizona's weather stations so that I can have values for all the variables necessary to calculate wet bulb globe temperature.

Week Eight

This week, we will be concluding experimentation, for a brief amount of time, setting us on track to begin data analysis starting next week.

On-Site Experimentation: 

Surgeries and experimentation take place as normal again this week. I will continue to help with record keeping and management of the laboratory, such as autoclaving pipette tips or putting together new rat cages. This week, I will begin compiling all of the current data, specifically the charts of defecation I have been putting together, and will be electronically storing them via an Excel Spreadsheet.

Retrospective Clinical Study: 

I have completed entering GPS coordinates of where patients were injured, and whether they were in a rural or urban area. Now, I will start calculating wet bulb globe temperatures for each case file. In order to do so, I will create individual case ID spreadsheets, which have the date and time of injury, duration of exposure to excessive heat or cold, GPS coordinates (and the three closest weather stations), as well as other variables, such as temperature (in Celsius), relative humidity, and solar irradiance. Each variable must be converted into a precise unit for me to determine the wet bulb globe temperature accurately.

Euthanization

For those of you who are not familiar with the term, euthanasia is the act of putting an animal to death. Within our laboratory, we euthanize for two purposes:

1. To obtain the rat brain for cryostat utilization
2. Lack of resources and funding to continue supporting the animal until natural death

As it is a sensitive topic, I will not go into any details regarding the process of euthanasia. However, I would like to make a few points regarding my experience observing and my knowledge from my animal handling and maintenance curriculum. 

Animal euthanasia is highly regulated, especially in the laboratory. Animals do not suffer; rather, the process minimizes, or even eliminates, pain and distress. Although it may seem rather cruel to some that these rats are obtained so that they can be experimented on and then euthanized, all animals are treated with dignity. I cannot stress it enough, all researchers who euthanize have humane dispositions. Meaning, they ensure the animal is treated with its due respect, and they complete the process quickly, to minimize suffering. 

Euthanasia is humane death. It minimizes or eliminates suffering, pain, discomfort, and distress for the animal, inducing a rapid loss of consciousness. Although I can say it is not a pretty sight to behold, it is important to understand and recognize that every animal is respected and treated with dignity, even in its final moments.

Week Seven

This week, I will be preparing for surgeries and experimentation. Additionally, I will conduct record-keeping. In regard to the retrospective clinical study, I am actively pursuing a modified procedure.

On-Site Experimentation: 

Surgeries and experimentation take place as normal again this week. Please see Week Three and Week Five for further details regarding preparation for surgery and experimentation. Specifically, my primary responsibility this week is to clean the thermogradient with ethanol and chart the location and quantity of the rat defecation, which is an indicator of stress levels. 

This week, as experiments take place, I will be completing records on the newly arrived rats, including the timeline set in place for them. As they arrived on March 21, 2016, their handling begins on March 22, with a datalogger surgery on March 23, followed by a recovery period and then their experiment in the thermogradient. In preparation for surgeries, I autoclaved glassware and surgical tools.

We expect to conclude experimentation next month and begin data analysis, so more to follow regarding our findings.

Retrospective Clinical Study:

During our retrospective clinical study, I was given a Microsoft Excel spreadsheet with all of the patient case IDs and the relative GPS coordinates where they were injured. The GPS coordinates are very important in determining if the patient was in an urban or rural area, which has an effect on solar irradiation. As some GPS coordinates were missing, Dr. Romanovsky has asked that I revise all of the GPS coordinates, to ensure their accuracy. For some cases, the trauma registry only has county or city, so for these cases, I use judgement of whether the patient was likely in a rural or urban setting. As these cases have been selected from Arizona, this is relatively easy; for example, if a patient was injured in Maricopa County (the fourth-most populated county in the United State), I presume they were in an urban setting.

While this approach may be not be the most precise, it is sufficient for our calculations. As of now, I am still processing GPS coordinates into our database. After this, I can begin redoing the calculations.