 |
 |
31.Mutant (yellow,
green) and wildtype (red) viral strains infect vulnerable CD4 cells in the bloodstream. In
the absence of totally suppressive therapy, drug resistant strains dominate the population
of viruses in the
|
individual. Rapid 'outgrowth' of the resistant strain leads to drug
failure.
Click here
to open PDF
Click here
to download image |
|
 |
|
32.Combinations of
drugs, such as a nucleoside reverse transcriptase inhibitors, a non-nucleoside reverse
transcriptase inhibitor and a protease inhibitor, have been shown to suppress viral loads
below the level of detection of current assays.
|
Click here
to open PDF
Click here
to download image |
|
 |
|
33.Nucleoside reverse
transcriptase inhibitors (NRTIs) prevent viral replication by supplying a non-functional
nucleoside (a 'wrong building block') during the synthesis of a DNA copy from the RNA
strand. (NRTIs) have to be metabolised |
in the body before the onset of action.
Click here
to open PDF
Click here
to download image |
|
 |
|
34.Non-nucleoside
reverse transcriptase inhibitors (NNRTIs) such as nevirapine prevent viral replication by
binding to reverse transcriptase directly. This inhibits the enzyme and prevents it from
synthesising a DNA copy
|
of the RNA strand. NNRTIs are active in their native state and so
do not need to be metabolised in order to exert an antiretroviral effect.
Click here
to open PDF
Click here
to download image |
|
 |
|
35.Perinatal
transmission of HIV from mother to baby is the major cause of HIV infections in children
worldwide. In the absence of therapy, approximately 25% of babies born to HIV-infected
women acquire the infection. A study
|
known as ACTG 076 demonstrated that the
administration of zidovudine to the pregnant mother and her newborn significantly reduced
the rate of transmission of HIV (to 8.3%). Studies are in progress to identify
combinations of antiretroviral drugs including nevirapine which can reduce or prevent
perinatal transmission of HIV.
Click here
to open PDF
Click here
to download image |
|
 |
|
36.HIV is able to
infect the central nervous system (CNS), including the brain. The CNS has been shown to be
a major reservoir of virus. Not all of the available antiretroviral drugs are able to
cross the blood:brain barrier and enter the CNS,
|
however. Many HIV specialists believe
that combinations of antiretroviral drugs should include at least one drug which is able
to penetrate the CNS. Drugs such as nevirapine and zidovudine have been shown to enter the
cerebrospinal fluid.
Click here
to open PDF
Click here
to download image |
|
 |
|
37.Nevirapine is a
potent inhibitor of viral replication. It has a limited effect on cellular metabolism.
Nevirapine has a rapid onset of action: it does not need to be metabolised in order to
become active and has high
|
bioavailability in all tissues.
Click here
to open PDF
Click here
to download image |
|
 |
|
38.Combinations of
drugs, such as two nucleoside reverse transcriptase inhibitors and a non-nucleoside
reverse transcriptase inhibitor, have been shown to suppress viral loads below the level
of detection. In the INCAS trial, a
|
combination of zidovudine, ddI and nevirapine induced
substantial and sustained reductions in viral load in a group of antiretroviral-naive
patients.
Click here
to open PDF
Click here
to download image |
|
 |
|
39.Even though we do
not have a cure for HIV disease, we must strive to prolong meaningful lives and change HIV
from a fatal disease to a controlled chronic illness and, if possible, eradicate HIV from
the body....
|
Click here
to open PDF
Click here
to download image |
|
