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Flu Pathophysiology
Once the flu virus enters a cell it can turn that cell into a viral factory making many more copies of the flu virus and causes illness.
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What is Pathophysiology?(10 votes)
Pathophysiology is a convergence of pathology with physiology. Pathology is the medical discipline that describes conditions typically observed during a disease state, whereas physiology is the biological discipline that describes processes or mechanisms operating within an organism. Pathology describes the abnormal or undesired condition, whereupon pathophysiology seeks to explain the physiological processes or mechanisms whereby such condition develops and progresses.(9 votes)
- How does the body increase its temperature during illness?(5 votes)
The white-blood cells (macrophages) release pyrogens into the bloodstream when they come in contact with bacteria and viruses. When the pyrogens arrive at the hypothalamus (in the brain) they bind to receptors in the hypothalamus which cause the body temperature to rise.(12 votes)
- At2:38it is mentioned that the immune system recognizes the viruses and has different ways to deal with them. Is it possible that one virus imitates another's shell but needs to be destroyed in a different way by the immune system,thus neutralizing the power of the immune system?(4 votes)
at1:24, what are the different types of proteins for the flu?(1 vote)
Hemagglutinin (HA) and Neuraminidase (NA)--they are two of the main types of proteins on the surface of the virus that the immune system, especially antibodies, B cells and T cells, can recognize.
http://www.sinobiological.com/Influenza-Hemagglutinin-Subtypes-and-Flu-Virus-Strains-a-144.html(2 votes)
I thought that when the virus left your body, it would mutate so your body won't recognize the same virus again, is this true?(1 vote)
Yes, this depends. When you are first presented with a virus, your body undergoes a "primary" response which takes weeks for your body to develop antibodies against the virus. To save time in the future, your body makes "memory" cells that remember the signal (antigen) that this specific virus so it can act more quickly (this time 2-7 days) if the virus ever attacks again. If however, the virus mutates so it changes it's signal, then the body has to go through the entire cycle of making new memory cells again.(1 vote)
2:38Video transcript
There are three groups
of influenza viruses, which we call virus types. And these three types are
influenza A, B, and C. So we group influenza
viruses like this because of the differences
that they have in their genetic
material or their genome. So the genome in an
influenza A virus is very different than the
genome in the influenza B virus, and there are many more
differences between A and B than there are between
two influenza A viruses. So I'm focusing right now on
influenza A and B viruses, because these are the types that
cause sickness and epidemics every winter in
the United States. I'm not focusing on
influenza type C, because this is much
less common in humans and actually isn't even
included in the annual vaccine. So now let's get back
to the differences between individual virus types. So the influenza type A is a
very large group of viruses, much larger than the
type B. And so we need to further divide this
group according to subtype, and the subtype
is named according to surface proteins that are
on the outside of every virus. So there are two kinds
of surface proteins on every influenza
A virus, and we call these H for hemagglutinin
and N for neuroaminidase. Now, these surface proteins
come in many different flavors. There are actually 17 different
kinds of hemagglutinin proteins and 10 different kinds of
neuroaminidase proteins. So when a virus
replicates, its genome is going to determine what
kinds of H and N proteins will show up on the
surface of the virus. So you can imagine
that there are a lot of different
combinations of these viruses. So H1N1 could be a potential
combination, maybe H3N2, and so on. And actually, H1N1 and
H3N2 are the subtypes that we see in humans today. So the combination of proteins
that we see in these viruses is very important, because this
is what the immune system sees when a virus enters the body. It sees what's on the
outside of the virus. So when you have two
viruses that are the same or that look the
same on the outside and if the immune system knows
what to do with one of them, it'll know what to do
with the other one. But if you have a
virus come along that looks very
different from a virus that the immune system
has ever seen before, it's going to be
very confused and not know what to do
with this new virus. And when this happens, this
is what causes major illness across an entire population. And we'll learn more about
that in a future module.