Biology Animations includes selected, high quality biological animations; about cell biology, microbiology, genetics, immunology, cancer treatments and diagnosis...
The Hemophilia Society of Turkey
for detailed information:
http://en.wikipedia.org/wiki/Coagulation
related links
http://www.turkhemoder.org/ (türkiye hemofili derneği)
avian flu animation
Seasonal Influenza
Responsible for the influenza that we see every fall and winter. (There are 3 types: A, B, and C)
Influenza A is responsible for most human disease and is the source of all past pandemics
The virus changes slightly during the flu season and as it migrates from the northern to southern hemispheres.
Because the virus changes so frequently, one vaccine does not give lifelong immunity
These changes are monitored and the annual flu vaccine must be designed to try to match these changes.
Named by H#N#s - these signify proteins on the virus envelope – diff. subtypes
Within these subtypes there are different strains
Through prior exposure to similar flu virus strains and from the vaccine, many people have partial immunity to the current circulating strain.
Annually, the US experiences 30 – 40K deaths from seasonal influenza.
Current Avian Flu (H5N1): Human Disease
Human infections have occurred in 10 countries in East Asia & the Pacific, Europe & Eurasia, and the Near East.
There have been a total of 256 confirmed infections and 151 deaths in humans (10/16/06).
Virus is not efficiently spread between birds/humans and humans/humans.
Why Are We Worried About Avian Flu?
Rapid spread through poultry flocks in Asia.
Although rare, has caused severe disease in humans.
Ongoing exposure and infection in humans in rural Asia and Europe (in association with free-ranging poultry flocks).
Co-infection with pig or humans infected with influenza could lead to genetic reassortment.
Could create new flu type easily transmitted from human-to-human (i.e. create a pandemic).
hepatitis c animation
What is it?
Hep C is a liver infection caused by a virus
Also known as non A, non B hepatitis
Hepatitis C Incubation period
6-7 weeks on average (range 2-6months)
infectious one or more weeks before getting ill
chronic carriers remain infectious
Symptoms
3 out of 4 persons have no symptoms and can infect others without knowing it
Who is at risk?
About 35,000 people get Hep C every year
down from 180,000 in the 1980s
About 3.9 million people in the USA are infected with Hep C.
It can cause liver failure, cirrhosis, liver cancer
Responsible for 8,000 to 10,000 deaths/year.
Diagnosis
There is a blood test that screens for Hep C antibodies (ELISA or RIBA)
Antibodies usually develop within 3 months
HIV+ persons may not develop detectable antibodies
There is a PCR test (detects parts of actual virus) for Hep C but it is not yet FDA approved
If infected, liver enzyme tests or a liver biopsy can check liver function
for detailed information :
www.metrokc.gov/HEALTH/apu/healthed/power/hepatitis/Hepatitis.ppt
drug resistance animation
Given the danger of an unprecedented spread of the highly pathogenic avian influenza strain H5N1 in humans, and great challenges to the development of an effective influenza vaccine, antiviral drugs will probably play a pivotal role in combating a novel pandemic strain. A critical limitation to the use of these drugs is the evolution of highly transmissible drug-resistant viral mutants.
control of gene expression animation
Gene expression indicates what is going on in a cell or structure at a given time
Microarrays allow a scientist to look at the gene expression of literally thousands of genes all at once.
Eukaryotic gene expression is a complex affair:
Many gene products can be encoded by one “gene.”
Gene expression is regulated at multiple levels.
Gene-encoded information is “compressed” and overlapping