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Cells, Microbes & Viruses / Myoglobin

« on: 02/02/2008 05:58:35 »

It's actually not in the myoglobin, Dr. Satan, your evil-ness. It's all in the ability to regulate your metabolism and how your brain uses up oxygen... Try these two great resources: typhoon.wcp.muohio.edu/Boardman/GLG244/Presentations/04Dec/Diving.ppt AND
http://www.uwrf.edu/biology/electives_dir/444_dir/VSmith/Page1.html

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Cells, Microbes & Viruses / osteoclast

« on: 02/02/2008 05:53:03 »

Try this site, it's quite good: http://www.courseweb.uottawa.ca/medicine-histology/English/Musculoskeletal/Default.htm

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Cells, Microbes & Viruses / blood groups

« on: 02/02/2008 05:40:20 »

Blood groups come from the kind of antigen on your red blood cells. Type A is one antigen (sugar molecule), type B is another, and type O is actually no antigen. Then you have the Rh-group, the Duffy, and all sorts of other blood groups. But ABO and Rh are the big ones because they must match your own group, or you risk developing an immune reaction against them.

Dogs and cats, and other mammals type as "O" not because they are O's like humans, but because they don't have the same antigens as we do. While it would be tempting to give someone this blood, the animal's blood has other antigens not like ours which would cause our immune systems to violently react against it, making us very, very sick.

As to the evolution of blood groups... We all have the genes to make A, B, or no (type O) blood, but only some get expressed. So it is safe to say that, yes, environmental pressures had something to do with it. To what extent? Well, it is known that certain bacterial infections, drugs, and animal venoms will change the antigen coating of your cells... So that could be an avenue. Does one type have an advantage over the other? Maybe.

For example, type O people can only get type O blood. Type AB people can get any type of blood. You would think that, as blood transfusions are more and more common to save people in otherwise life threathening situations, those with AB blood would be saved more often than those with rarer blood types, thus passing on the genes... But that's the catch. A type AB person can have children that are A's, B's, or AB's!

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Cells, Microbes & Viruses / What are the commonest water-bourne viral and bacterial diseases?

« on: 02/02/2008 05:33:08 »

Of course, you also have to worry about parasites and chemical contaminants that can also make water unsafe to drink. One parasite, cryptosporidium, caused a severe outbreak of diarrhea in Milwalkee, Wisconsin, USA, when the water treatment plant failed. Interestingly enough, the beer was about the only safe thing to drink in the town for a few days! Most people recovered, but those with HIV/AIDS suffered the effect long-term.

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Cells, Microbes & Viruses / Coughs and Sneezes spread diseases...But how?

« on: 02/02/2008 05:29:34 »

Yes, the viruses (flu, cold, SARS) and bacteria (tuberculosis, pertussis) are in the droplets. In the case of viruses, the viruses are in epithelial cells contained in the droplets, too. That's why they can survive drying, because they will still be cocooned inside the cells fora little while longer. This is why it is important to not just wipe a surface with disinfectant. You must get the surface wet with disinfectant and let it sit there a while to really disintegrate all cells and viruses you're trying to kill.

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Cells, Microbes & Viruses / Re: What causes "food poisoning" ?

« on: 02/02/2008 05:24:59 »

Viruses: Norovirus, Hepatitis A (and sometimes B, C), and some of the respiratory viruses as well...

Bacteria: E. coli, Salmonella, Shigella, Vibrio cholerae, Clostridium, etc.

Parasites of all kinds: Trichinella, for example.

Toxins made from bacteria and fungi: Botulinum toxin, aflotoxin, Shiga toxin (the bacteria can be long dead and the toxins will get you)

Amoebas: Entamoeba, trichuris, etc.

Tons of stuff can make your belly sick!

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Cells, Microbes & Viruses / Re: Where does pandemic / avian flu originate?

« on: 02/02/2008 05:17:51 »

Believe it or not, all of these news are good news. It means that epidemiologists all over the world are using their surveillance systems to keep track of H5N1, and other flu viruses. We (because I'm one of the epidemiologists) can then keep everyone in the loop on what viruses are coming up, where, when, and, sometimes, how. I would be more worried if I didn't hear news of where the virus is, knowing that it's as pathogenic (not really too virulent right now) as it is.

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Cells, Microbes & Viruses / Warts

« on: 02/02/2008 05:05:08 »

Nearly 100 different types of Human Papillomavirus cause genital warts, other viruses cause other kinds of warts as well. These viruses, whent they get into your epithelial skin cells, hijack the cells' reproduction "machinery". That is, they incorporate their own DNA or RNA into the cells' DNA. When the cell goes to reproduce, it instead makes copies of the virus. As the DNA is hijacked, some of these changes activate certain codes within the DNA that make the cell reproduce many times over. This is the wart that you see... It's what we call a neoplasm, or new growth. Sometimes, warts serve the purpose of being a barrier between the infected cells or pus vesicles and other cells, to keep the virus from spreading. Other times, they do completely the opposite... The warts might be loaded with virus and help the virus jump to other cells (or people).

As to the methanol/ethanol question... Those chemicals dry out tissues. We use them in the lab to take water out of tissues and replace the water with, say, wax, so we can slice the tissue thin and look at it under the microscope. Perhaps when applying the alcohol to the wart, it dries the wart, so it falls off. I don't recommend at-home treatments for genital warts, or moles that look like warts. You should alway seek medical care before performing procedures on yourself. Come on, you've heard Dr. Chris... You know better!

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Physiology & Medicine / "To Err is Human"....why ?

« on: 02/02/2008 04:56:33 »

What is a mistake but just an outcome that doesn't live out to the expectations of the actor or the viewing audience? I am a strict believer that things work out the way they're supposed to, and it's up to us to accept the result. Whoa! I just got all philosophical on that one!

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Radio Show & Podcast Feedback / Discuss: Flu and Viruses

« on: 01/02/2008 19:24:28 »

I would be honored to write something up. There are two options, however... I could write as an epidemiologist and just talk about how we go about investigating disease, or I could write as an epidemiologist for the State of Maryland, which would require clearance from my superiors. I'm also a Medical Technologist, and I include the laboratory component to my job as an "epi". Is there a particular topic you guys need covered?

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Radio Show & Podcast Feedback / Discuss: Flu and Viruses

« on: 01/02/2008 17:42:26 »

FYI: http://www.edcp.org/influenza/Influenza_serv.html if you want to know how flu is going on this side of the Atlantic. I keep tabs on how things are on your side because how you go is generally how we go... And how Australia goes in June/July/August is how we seem to go during our season. Great show, by the way... Keep making science interesting!

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Radio Show & Podcast Feedback / Discuss: Flu and Viruses

« on: 05/11/2009 10:57:11 »

It's funny that you picked that picture for your show podcast. I am the influenza surveillance coordinator for the State of Maryland in the US, and I have that same picture on our site where I publish our surveillance findings. It must be a popular pic.