21 November 2009

Don't Sneeze On Your Cat!

As a self-proclaimed “cat lady” I decided that the recent confirmation of the transmission of the H1N1 influenza virus from humans to cats is appropriate to blog about. On November 4, 2009, it was reported and confirmed that a 13-year old cat in Iowa contracted the H1N1 influenza virus. Since then, more cats have been diagnosed with H1N1 and there has been one presumed, yet not confirmed, death.

When two members of an Ames, Iowa, family came down with the H1N1 flu, the family pet, a 16-pound orange tabby, became lethargic, lost his appetite, and was showing signs of respiratory discomfort. Fortunately they were able to call a family friend, Dr. Brett A. Sponseller, who is a specialist in large animal internal medicine and molecular virology at the College of Veterinary Medicine at Iowa State University. Dr. Sponseller and his colleague Dr. Albert Jergens conducted many tests and concluded that the cat indeed had H1N1 influenza.

This story is unique because it is the first case of a feline contracting influenza from a human, which has created concern for health officials and pet owners alike. There have been cases of companion animals acquiring the flu from other species. The canine influenza (H3N8) began in horses, and cats have been known to contract avian influenza (H5N1) from eating birds. However, the feline H1N1 case in Iowa remains the first time a cat has contracted influenza from a human. To date this virus has been confirmed in three pet ferrets, turkeys in Chile and Canada, and has also been transmitted between humans and pigs.

Since then, there have been more confirmed cat H1N1 cases. On November 17th 2009, a cat in Park City, Utah became the second confirmed H1N1 feline case. The owner contracted the H1N1 flu and noticed flu-like symptoms in the cat – similar to the Ames family. On November 18th, 2009, the Oregon State public health veterinarian reported that a pet cat died from presumed H1N1 influenza virus infection approximately one week after a child in the household had flu-like symptoms. The cat shared a household with three other cats – all of which became ill with less severe sneezing and coughing symptoms.

Even though veterinarians and health care officials are uncertain of how the cats contracted the virus, it is known that the flu is easily transmitted between family members, and it is not surprising that a sociable cat would come into contact with the virus making it more susceptible. It is important to note that according to Dr. Sponseller, there is no evidence that a cat can transfer the H1N1 virus to a person because cats with flu typically don’t cough or sneeze.

This situation has fostered more “swine” flu panic and has raised many questions. How can a cat get H1N1 from humans? What makes this influenza virus transmittable to cats? Can a cat transfer H1N1 to humans? Can other companion animals such as dogs get H1N1? Will there be a H1N1 vaccine for pets? Until more is learned about the transmission of the H1N1 influenza virus, many of these questions will remain unanswered.




Parker-Pope, Tara, “The Cat Who Got Swine.” The New York Times. The New York Times Company. November 5th, 2009. Web. November 17th, 2009. <http://well.blogs.nytimes.com/2009/11/05/the-cat-who-got-swine-flu>.

“2009 H1N1 Flu Virus Outbreak” AVMA. American Veterinary Medical Association. November 18th, 2009. Web. November 20th, 2009. <http://www.avma.org/public_health/influenza/new_virus/>.

Alzheimer’s Disease- Oral hygiene

Disclaimer: This post may come off as insensitive.
I just finished reading an article titled “Trouble Thinking? Better See the Dentist” found here http://www.reuters.com/article/newsOne/idUSTRE5AC06O20091113.
Let me start off by saying I worked in a dental office for 2 years.
The patients who came in with the WORST cases of Periodontitis & Calculus were usually the most uneducated and apathetic patients we would see. For some, a lifetime of calculus would cake onto their teeth so badly that they thought their teeth were simply growing. That’s what I said: THEY THOUGHT THEIR TEETH WERE GROWING!
For these patients, the only thing more painful than seeing the dentist would be reading The Great Gatsby. But I digress.
The Amyloid Hypothesis associated with chronic inflammation has been questioned as a causative factor in the pathogenesis of Alzheimer’s disease. Granted, I saw plenty of inflamed gum tissue in my time working in a dental office. But these epidemiological studies are simply telling me that the less health conscious individuals are showing early signs of Alzheimer’s disease for the sake of being unhealthy. What frustrates me is the scientific spin on it “those with the highest levels of the gum disease-causing pathogen Porphyromonas gingivalis were three times more likely to have trouble recalling a three-word sequence after a period of time.” When a dentist assesses gum disease, they stick a probe in your gums and measure the depth. It takes 5 seconds, less if you don’t have gum disease. This article makes it sound like they cultured the Porphyromonas gingivalis and really narrowed it down as a pathogen for Alzheimer’s disease.
Growing up, my dad would always tell me “Sit mens sana in corpore sano”, which is Latin for “a healthy mind in a healthy body” (my mom is Latina; dad is from New York…he says it in Latin to look cool). I think we should continue looking into the Amyoloid Hypothesis as a pathophysiological factor in the progression of Alzheimer’s Disease. However, I think there are things we control on a day to day basis that can make our brains healthier and more useful.

20 November 2009

Clean Pigs and Diabetes

I came across this cool report in Science about a group looking to use pig pancreatic islet cells in human patients. You can check it out here:
Science 20 November 2009:
Vol. 326. no. 5956, p. 1049
DOI: 10.1126/science.326.5956.1049-a

Basically there are a few centers in the world raising pigs in sterile environments for islet cell harvest. By transplanting the pig islet cells into human autoimmune diabetes patients the hope is that the pig cells will not be susceptible to the autoimmune response to human islet cells. Hopefully, these cells will act as a near-term solution while the bugs are being worked out of a similar human stem cell approach.

Since pig tissue in a human will obviously mount a strong immune response the New Zealand group is "encapsulating the islets in material that will fend off immune attack while allowing insulin out. The Minnesota team is still working on an immunosuppression regimen that will allow the use of "naked islets," says Schuurman, which the scientists think will have better access to nutrients. Further down the road, scientists at the University of Pittsburgh and elsewhere are working on techniques for shuffling pigs' genes or conditioning patients' immune systems to narrow the species gap."
Obviously the biggest hurdles will be working out the regulatory issues related to grafting living pig tissue into humans to permit clinical trials. An interesting and kind of crazy idea.
What do you guys think about this? What are some of pros and cons you can think of with this approach?

19 November 2009

Scale for the Severity of Disease State in EAE

During our discussion on multiple sclerosis last class we discussed the animal model of multiple sclerosis called Experimental Autoimmune Encephalomyelitis (EAE) as a tool to determine the effectiveness of treatments for multiple sclerosis. In the paper by Tsutsui et al. it was mentioned that the animals were assessed daily for EAE severity but it did not elaborate on how this was quantified in a consistent manner.
By tracing back through the references I found in the journal Natural Medicine (Liu et. al.) that severity of EAE was determined on a scale from 0-5 according to function. A score of 0 indicates that the disease is not apparent in the mobility of the animal. A score of 1 indicates mild physical signs including weight loss and tail weakness. 2 indicates mild paralysis in the hind limbs, a 3 indicates complete paralysis of the hind limbs. A 4 indicates hind limb paralysis with fore limb weakness or paralysis and finally a 5 indicates moribund (approaching death) or death.
As useful as this scale is it is unfortunate that the limit to its usefulness is limited to very advanced degrees of disease state. In humans with multiple sclerosis we know that there is a range of other problems in the early stage that manifest themselves early before obvious motor problems are manifested that this model could not be used to investigate.

18 November 2009

Stem cells and all Neurodegenerative diseases

Knowing that stem cells can differentiate into multiple cell types or all cells of the body (depending on their origin), transplantation of stem cells into an adult brain has been proposed as a future therapy for neurodegenerative diseases.
In each type of neurodegenerative disease (Hunnington’s disease, Alzheimer’s disease, Parkinson’s disease, ALS), there are many different cell types involved in their pathology, thus, different types of neurons are required for replacement.
This article http://celleng.sjtu.edu.cn/pic/xq19.pdf analyzes many neurodegenerative diseases and their potential for stem cell therapy. They show the challenges in the way for stem cell therapy, for we need to know how to pattern stem cells to obtain a more complete repertoire of various cell types for replacement. How are stem-cell-derived neurons integrated into an adult brain’s existing neural and synaptic network? How can we modify stem cells appropriately to treat a particular disease?
To identify the self-repair mechanisms of the brain, we’ll require a new technology for genetically labeling stem cell progeny. The hope is this knowledge will allow us to figure out a strategy to deliver new molecules that can yield functional neurons/cells in damaged areas.

17 November 2009

Converting RBC Blood Groups by Cleaving Terminal Sugars

It struck me in class today that, with an enzyme to cleave either the A or B sugar from the end of the blood group glycolipid, you could create a 'O' erythrocytes from A, B, or AB individuals, expanding our supply of 'universal donor' blood while drastically reducing the risk of accidental mismatch.

As it turns out, I was not the first to have this idea - way back in 1983, it was demonstrated that a galactosidase derived from coffee beans is able to convert B RBCs into O, and that these cells are viable in people of any blood type (excluding the Bombay phenotype). Unfortunately, this method, and many others attempted for both A and B sugars, required a prohibitively large amount of enzyme and incompatable conditions, preventing its practical large scale use.

Recently (2007), researchers, doing a large scale scan of bacterial and fungal isolates, isolated two novel galactosidases which remove the A and B sugars much more efficently, and with identical, neutral pH, reaction conditions - allowing for the conversion of AB eyrithrocytes as well as A and B. Standard typing showed full conversion of any of the groups to O.

With a quick search, I wasn't able to find any more information on more progess towards making this a reality in blood banks, but hopefully someone's working on it...

References:

Liu Q, Sulzenbacher G, Yuan H, Bennett E, Pietz G, Saunders K, Spence J, Nudelman E, Levery S, White T, Neveu J, Lane W, Bourne Y, Olsson M, Henrissat B, Clausen H (2007). "Bacterial glycosidases for the production of universal red blood cells". Nat Biotechnol 25 (4): 454

Group B erythrocytes enzymically converted to group O survive normally in A, B, and O individuals. Goldstein, Jack; Siviglia, Geraldine; Hurst, Rosa; Lenny, Leslie; Reich, Lilian, Science (1982), 215(4529).

15 November 2009

Sea anemone toxin may provide relief for MS patients.

Having read, A randomized crossover study of bee sting therapy for multiple sclerosis by Wesselius & Heersema et al., I was interested in other possible applications of animal venom in treatments similar to the apitherapy frequently used as an alternative care source for MS patients. In my inquiry I found an article on a sea anenome toxin that may act beneficially in the relapse of MS patients.

By Norton, Pennington and Wulff, Potassium Channel Blockade by the Sea Anemone Toxin ShK for the Treatment of Multiple Sclerosis, provides an overview of interaction between the toxin and potassium channels, the role of potassium cell in T-cells and the changes in potassium expression during T-cell differentiation.

Norton et al., site studies which state provide evidence showing that ShK has been able to prevent and treat adopted experimental autoimmune encephalymyelitis (EAE) in rodent models. ShK subcutaneously injected prevented EAE in a study in which all control animals died. ShK was even proven to ameliorate symptoms when treatment with ShK was delivered until after the presentation of the first symptom.

Ultimately, this paper provides just another example of possible solutions to human diseases that may be lie latent and undiscovered in other species. I always try and look at the human body holistically when discussing diseases, thinking of how all the systems interact; however, I think this articles reassures the discussion about preserving as many endangered species as possible, as we may not truly understand the potential that those animals hold.

Reference for the article: http://web.ebscohost.com/ehost/pdf?vid=2&hid=8&sid=8f2a0a67-151f-49cc-8910-280672d21490%40sessionmgr13