Tuesday, March 31, 2015

Putting my Pen to Paper




...or rather, my fingers to the keyboard. This week marks the beginning of my paper writing marathon. Luckily, I have previous knowledge and sources about the history of bionics. I'm still working on developing a strong thesis. My original question was how can bacteria alter the growth of connective tissues between the stump of the individual and the bionic device, but this question requires extensive research. I'm looking into expanding my topic a bit more. I hope to use much of the research I've done with this blog to supplement my paper. If I stick to my outline, my main topics will be bacterial disease caused by implantation, positive effects of bacteria on bionic devices, and how bionics improve one's body functioning. Hopefully, I can provide more insight as the weeks progress, so stay tuned! 

Tuesday, March 24, 2015

Case Studies and Bionics

Case Studies! They are critical to looking into specific problems that might occur in researching or testing of various devices. When I began my project, I read a case study titled "Risk of Bacterial Meningitis in Children with Cochlear Implants." This case identified 26 children with bacterial meningitis.  The incidence of meningitis caused by Streptococcus pneumoniae was 138.2 cases per 100,000 person-years. The case speculates if positioners (a wedge inserted next to the implanted electrode to facilitate transmission of the electrical signal by pushing the electrode against the medial wall of the cochlea) are the cause of bacterial meningitis. The study states, "The incidence of meningitis among patients who had received an implant with a positioner remained higher than the incidence among those whose implants did not have a positioner for the duration of follow up." Later, the case says that the incidence of meningitis is not fully explained by the positioner. The study analyzed various surgical procedures that may be the cause of the onset of bacterial meningitis: incomplete insertion of the electrode, the presence of a cerebrospinal fluid leak, which is defined as a preexisting leak or an intraoperative leak or "gusher" resulting in rapid leakage of cerebrospinal fluid during surgery, and the use of antibiotic. The table below shows the 26 children that received a cochlear implant and experience episodes of post implantation bacterial meningitis:



Another very interesting study, done by Boston University in conglomeration with The Barton Center for Diabetes Education, studied young children in a very active environment, a sleep away camp. The study is testing how well a bionic pancreas will do in highly active environments. The bionic pancreas continuously adapts to the individuals varying insulin levels by administrating the necessary doses. This allows the individual to play sports without losing energy quickly and to not have to worry about testing their blood sugar several times a day. Below is a video explaining the study and its mission:


Thanks for reading and stay tuned!

Sources:

  1. Reefhuis, J., Honein, M., Whitney, C., Chamany, S., Mann, E., Biernath, K., ... Boyle, C. (2003). Risk Of Bacterial Meningitis In Children With Cochlear Implants. New England Journal of Medicine, 435-445
  2. (n.d.). Retrieved March 24, 2015, from http://www.bartoncenter.org/About-Barton
  3. Russell, S., El-Khatib, F., & Sinha, M. (2014). Outpatient Glycemic Control with a Bionic Pancreas in Type 1 Diabetes. The New England Journal of Medicine.

Tuesday, March 17, 2015

The Luck of the Bionic



You may not want to leave it all up to luck when choosing to go through with a prosthetic implantation. Much precaution and careful consideration of a variety of factors must be taken into account. Last week, I discussed several guidelines to prevent infection before/during/after surgical procedures. Today, I want to talk about specific prevention procedures for several implants. In order to make the explanation very clear, I will be using an outline format with the following subsections: Infection, Symptoms, and Prevention Procedure. 
  1. Intraocular Lens Implants
    • Infection: staphylococci and Staphylococcis aureus 
    • Symptoms: ocular pain, decreased vision, headache, and photophobia (abnormal intolerance to visual perception of light)
    • Prevention Procedure: 5% poviodone-iodine solution and 10% iodine wash of the lids (commonly recommended as a preoperative disinfectant) 
  2. Prosthetic Joints
    • Infection: The incident of infection of total joint prostheses over a 10 year span at one institute was 1.7%. Most common pathogens are the staphylococcus species. 
    • Symptoms: pain, spontaneous wound drainage, failure of wound to heal in the early postoperative period
      • Curing may require a combination of device removal and antibiotics. 
    • Prevention Procedure: 1 gram of cefazolin before surgery and then no more than two or three doses postoperatively. 
  3. Dental Implants 
    • Common Infection: Streptococcus sanguis, Actinomyces viscosus, Actinomyces odontolyticus 
    • Symptoms: inflammation, plaque build up, bleeding
    • Prevention Procedure: perioperative chlorhexide (0.12%), twice daily mouth rinse with antiseptic reduces plaque formation on dental implants
  4. Cochlear and Ossicular Implants
    • Infection: meningitis 
    • Symptoms: fever, headache, confusion, sensitivity to light
    • Prevention Procedure: prophylactic antibiotic in cochlear implant operations 
Hope this section is helpful. If anyone would like more information on the above or other commonly used prosthetic devices, please comment below. Otherwise, stay tuned for next week as I dive into some case studies and further uncover The Intriguing Connection. 

Sources: 
  1. Meningitis. (n.d.). Retrieved March 17, 2015, from http://www.mayoclinic.org/diseases-conditions/meningitis/basics/symptoms/con-20019713
  2. Prevention of Infection in Prosthetic Devices. (2006). In F. Johnson & K. Virgo (Eds.), The Bionic Human. Totowa, NJ: Humana Press.

Tuesday, March 10, 2015

Prevention is Key!


Greetings! Last week, I discussed bacterial growth and the bacterial growth curve. As promised, this week, I will be talking about the prevention of infection in prosthetic devices. Before I begin, I would like to go back about two weeks to my post "How to Control Someone Else's Computer." I left off without a solution to my problem. After careful research and multiple trials with various programs, I finally found one that works, WinSCP. It allows for transfer of data and remote access using a terminal window even if you are trying to connect a Mac and a PC. If you are interested in downloading this program, Click Here!

To continue investigating The Intriguing Connection, I looked at infection and bionics. My first look at this was through prevention. No one that gets a prosthetic hopes for infection to set in, so they take various means to prevent it from happening. There is no clearly defined guidelines for preventing prosthetic device infections. To begin, I want to give two examples of how the implantation process can facilitate infection. During and after implantation, there can be an inflammatory response around the foreign material hindering leukocytes to create a phagocytic response. In simpler terms, your body is unable to clean up harmful foreign particles, bacteria and dying/dead cells. Also, during implantation of joint prostheses, if polymethylmethacrylate cement is used, it polymerizes in situ (in its original place) by an exothermic reaction. This intense heat, exceeding 100 degrees C, may cause local tissue necrosis which favors bacterial growth.

Here are some general principles of infection prevention in prosthetic devices to follow: Preoperative Measures, Intraoperative Measures, and Postoperative Measures. Preoperative measures include treating or controlling any acute or chronic physical condition, giving special attention to any skin conditions, teaching good hygiene, and reducing hospital duration prior to surgery. Intraoperative measures include ultra-clean air in the operating rooms, careful skin preparation around the operative site, wound irrigation with saline or saline-antibiotic solutions, and antibiotic prophylaxis to prevent surgical site infections. Postoperative measures include removing any urinary and intravascular catheters or surgical drains as soon as the clinical condition allows. Commonly, the infection will happen in the early postoperative state rather than the late.

Side Note

The professor I am working with at the University of Arizona was an expert consultant on the new movie Chappie. Below is the featurette:


Additionally, he is quoted in several news articles. Click on any of the following titles to read more about Artificial Intelligence and ChappieCould Chappie's robot-policed future come pass?'Chappie' Doesn't Think Robots Will Destroy the WorldIs a Self-Aware Robot Like Chappie Possible?, and 'Chappie': How Realistic Is the Film's Artificial Intelligence?

Stay tuned for next week as I go in depth on specific treatments for the most commonly used prosthetic devices! 

Sources

"Phagocytosis." Phagocytosis. Web. 10 Mar. 2015. <http://textbookofbacteriology.net/Bact100/phago_defense.html>.

Simionescu, Ramona, and Donald Kennedy. "Prevention of Infection in Prosthetic Devices." The Bionic Human. Ed. Frank Johnson and Katherine Virgo. Totowa: Humana, 2006. Print.

"Phagocyte." Wikipedia. Wikimedia Foundation. Web. 10 Mar. 2015. <http://en.wikipedia.org/wiki/Phagocyte>.

Tuesday, March 3, 2015

The Beginnings of The Intriguing Connection

Now is the time where I begin to discuss The Intriguing Connection. I'm sure many of you have been on the edge of your seats. This week I embarked on learning about bacterial growth.

Bacterial growth is the asexual reproduction of a bacterium using a process called binary fission. This means it does not require a mate to reproduction. Additionally, all of the offspring (two daughter cells) are identical. The growth of bacteria is affected by physical and nutritional factors. Physical factors include pH, temperature, osmotic pressure, hydrostatic pressure, and moisture content of the medium (the place where the bacteria grows in order to meet these factors). Each of these physical factors can affect the growth rate of the bacteria. The faster/ slower the bacteria grow, the more/less they will undergo binary fission. Nutritional factors include the amount of carbon, nitrogen, sulfur, phosphorous, and other elements in the growth medium.

When we plot a curve of bacterial growth, this is unknown as the Bacterial Growth Curve. This curve has four distinct periods: The Lag Phase, The Log/Exponential Phase, The Stationary Phase, and The Death Phase. During the Lag Phase, the bacteria grow and adapt themselves to their new environment. No dividing takes place during this phase. The Log/Exponential Phase, as one might imagine, is where the amount of bacteria present grows rapidly or even exponentially. Following this phase is the Stationary Phase. During this time, the bacteria take in the essential nutrients to prosper but soon deplete their resources. Once there are no more nutrients, the temperatures in the medium are too extreme, or the living conditions are inadequate, the bacteria begin to die in a phase aptly named the Death Phase.  

Here's a table of generation times for some common bacteria in their optimal medium:



Watch this helpful lesson by Khan Academy to understand bacterial reproduction and the bacterial growth curve:



For a clearer explanation of the various parts of the bacterial growth curve refer to this animation:


Taking a side step away from the basics of bacterial growth, I recently watched this TED talk and was in awe by the technological advancement. This may not be explicitly bionics or prosthesis, but it deals with our body's reactions to bacteria, viruses, cosmetics, and even household cleaning products. Enjoy Geraldine Hamilton's Body Parts on a Chip!


Now that we understand the basics of bacterial growth, next week, I'll be talking about the Prevention of Infection in Prosthetic Devices. Stay tuned!   

Sources:
Bacterial Growth Curve
The Growth of Bacterial Populations
Bacterial Growth