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Antiretroviral Medicines
The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs as a strategy to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle. The use of multiple drugs that act on different viral targets is known as highly active antiretroviral therapy (HAART). HAART decreases the patient's total burden of HIV, maintains function of the immune system, and prevents opportunistic infections that often lead to death. HAART also prevents the transmission of HIV between serodiscordant same sex and opposite sex partners so long as the HIV-positive partner maintains an undetectable viral load. Treatment has been so successful that in many parts of the world, HIV has become a chronic condition in which progression to AIDS is increasingly rare. Anthony Fauci, head of the United States National Institute of Allergy and Infectious Diseases, has written, "With collective and resolute action now and a stead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiviral Drug
Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do not destroy their target pathogen; instead they inhibit its development. Antiviral drugs are one class of antimicrobials, a larger group which also includes antibiotic (also termed antibacterial), antifungal and antiparasitic drugs, or antiviral drugs based on monoclonal antibodies. Most antivirals are considered relatively harmless to the host, and therefore can be used to treat infections. They should be distinguished from viricides, which are not medication but deactivate or destroy virus particles, either inside or outside the body. Natural viricides are produced by some plants such as eucalyptus and Australian tea trees. Medical uses Most of the antiviral drugs now available are designed to help deal with HIV, herpes viruses, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HIV Tropism
HIV tropism refers to the cell type in which the human immunodeficiency virus (HIV) infects and replicates. HIV tropism of a patient's virus is measured by the Trofile assay. HIV can infect a variety of cells such as CD4+ helper T-cells and macrophages that express the CD4 molecule on their surface. HIV-1 entry to macrophages and T helper cells is mediated not only through interaction of the virion envelope glycoproteins (gp120) with the CD4 molecule on the target cells but also with its chemokine coreceptors. Macrophage (M-tropic) strains of HIV-1, or non-syncitia-inducing strains (NSI) use the beta-chemokine receptor CCR5 for entry and are thus able to replicate in macrophages and CD4+ T-cells. These strains are now called R5 viruses. The normal ligands for this receptor—RANTES, macrophage inflammatory protein (MIP)-1β and MIP-1α—are able to suppress HIV-1 infection ''in vitro''. This CCR5 coreceptor is used by almost all primary HIV-1 isolates regardless of viral gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adefovir
Adefovir is a prescription medicine used to treat (chronic) infections with hepatitis B virus. A prodrug form of adefovir was previously called bis-POM PMEA, with trade names Preveon and Hepsera. It is an orally administered nucleotide analog reverse-transcriptase inhibitor (ntRTI). It can be formulated as the pivoxil prodrug adefovir dipivoxil. Uses It is used for treatment of hepatitis B. Trials of adefovir in patients with HIV have not shown any clear benefits. History Adefovir was invented in the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic by Antonín Holý, and the drug was developed by Gilead Sciences for HIV with the brand name Preveon. However, in November 1999, an expert panel advised the U.S. Food and Drug Administration (FDA) not to approve the drug due to concerns about the severity and frequency of kidney toxicity when dosed at 60 or 120 mg. The FDA followed that advice, refusing to approve adefovir as a treatment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenofovir
Tenofovir disoproxil, sold under the trade name Viread among others, is a medication used to treat chronic hepatitis B and to prevent and treat HIV/AIDS. It is generally recommended for use with other antiretrovirals. It may be used for prevention of HIV/AIDS among those at high risk before exposure, and after a needlestick injury or other potential exposure. It is sold both by itself and together in combinations such as emtricitabine/tenofovir, efavirenz/emtricitabine/tenofovir, and elvitegravir/cobicistat/emtricitabine/tenofovir. It does not cure HIV/AIDS or hepatitis B. It is available by mouth as a tablet or powder. Common side effects include nausea, rash, diarrhea, headache, pain, depression, and weakness. Severe side effects include lactic acidosis, high blood lactate and an hepatomegaly, enlarged liver. There are no absolute contraindications. It is often recommended during pregnancy and appears to be safe. It is a Reverse-transcriptase inhibitor, nucleotide reverse tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emtricitabine
Emtricitabine (commonly called FTC, systematic name 2',3'-dideoxy-5-fluoro-3'-thiacytidine), with trade name Emtriva (formerly Coviracil), is a nucleoside reverse-transcriptase inhibitor (NRTI) for the prevention and treatment of HIV infection in adults and children. Emtricitabine is also marketed in a fixed-dose combination with tenofovir disoproxil (Viread) under the brand name Truvada, and with tenofovir alafenamide (Vemlidy) under the brand name Descovy. A fixed-dose triple combination of emtricitabine, tenofovir and efavirenz (Sustiva, marketed by Bristol-Myers Squibb) was approved by the U.S. Food and Drug Administration (FDA) on July 12, 2006, under the brand name Atripla. Emtricitabine makes up one fourth of the Quad pill (brand names: Stribild and Genvoya). In fixed-dose combinations with tenofovir or with efavirenz and tenofovir it is on the World Health Organization's List of Essential Medicines. In 2019, it was the 494th most commonly prescribed medication in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamivudine
Lamivudine, commonly called 3TC, is an antiretroviral medication used to prevent and treat HIV/AIDS. It is also used to treat chronic hepatitis B when other options are not possible. It is effective against both HIV-1 and HIV-2. It is typically used in combination with other antiretrovirals such as zidovudine and abacavir. Lamivudine may be included as part of post-exposure prevention in those who have been potentially exposed to HIV. Lamivudine is taken by mouth as a liquid or tablet. Common side effects include nausea, diarrhea, headaches, feeling tired, and cough. Serious side effects include liver disease, lactic acidosis, and worsening hepatitis B among those already infected. It is safe for people over three months of age and can be used during pregnancy. The medication can be taken with or without food. Lamivudine is a nucleoside reverse transcriptase inhibitor and works by blocking the HIV reverse transcriptase and hepatitis B virus polymerase. Lamivudine was patent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abacavir
Abacavir, sold under the brand name Ziagen among others, is a medication used to treat HIV/AIDS. Similar to other nucleoside analog reverse-transcriptase inhibitors (NRTIs), abacavir is used together with other HIV medications, and is not recommended by itself. It is taken by mouth as a tablet or solution and may be used in children over the age of three months. Abacavir is generally well tolerated. Common side effects include vomiting, insomnia (trouble sleeping), fever, and feeling tired. Other common side effects include loss of appetite, headache, nausea (feeling sick), diarrhea, rash, and lethargy (lack of energy). More severe side effects include hypersensitivity, liver damage, and lactic acidosis. Genetic testing can indicate whether a person is at higher risk of developing hypersensitivity. Symptoms of hypersensitivity include rash, vomiting, and shortness of breath. Abacavir is in the NRTI class of medications, which work by blocking reverse transcriptase, an enzyme n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zidovudine
Zidovudine (ZDV), also known as azidothymidine (AZT), is an antiretroviral medication used to prevent and treat HIV/AIDS. It is generally recommended for use in combination with other antiretrovirals. It may be used to prevent mother-to-child spread during birth or after a needlestick injury or other potential exposure. It is sold both by itself and together as lamivudine/zidovudine and abacavir/lamivudine/zidovudine. It can be used by mouth or by slow injection into a vein. Common side effects include headaches, fever, and nausea. Serious side effects include liver problems, muscle damage, and high blood lactate levels. It is commonly used in pregnancy and appears to be safe for the baby. ZDV is of the nucleoside analog reverse-transcriptase inhibitor (NRTI) class. It works by inhibiting the enzyme reverse transcriptase that HIV uses to make DNA and therefore decreases replication of the virus. Zidovudine was first described in 1964. It was approved in the United States i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Competitive Inhibitor
Competitive inhibition is interruption of a chemical pathway owing to one chemical substance inhibiting the effect of another by competing with it for binding or bonding. Any metabolic or chemical messenger system can potentially be affected by this principle, but several classes of competitive inhibition are especially important in biochemistry and medicine, including the competitive form of enzyme inhibition, the competitive form of receptor antagonism, the competitive form of antimetabolite activity, and the competitive form of poisoning (which can include any of the aforementioned types). Enzyme inhibition type In competitive inhibition of enzyme catalysis, binding of an inhibitor prevents binding of the target molecule of the enzyme, also known as the substrate. This is accomplished by blocking the binding site of the substrate – the active site – by some means. The Vmax indicates the maximum velocity of the reaction, while the Km is the amount of substrate needed to r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Transcriptase
A reverse transcriptase (RT) is an enzyme used to generate complementary DNA (cDNA) from an RNA template, a process termed reverse transcription. Reverse transcriptases are used by viruses such as HIV and hepatitis B to replicate their genomes, by retrotransposon mobile genetic elements to proliferate within the host genome, and by eukaryotic cells to extend the telomeres at the ends of their linear chromosomes. Contrary to a widely held belief, the process does not violate the flows of genetic information as described by the classical central dogma, as transfers of information from RNA to DNA are explicitly held possible. Retroviral RT has three sequential biochemical activities: RNA-dependent DNA polymerase activity, ribonuclease H (RNase H), and DNA-dependent DNA polymerase activity. Collectively, these activities enable the enzyme to convert single-stranded RNA into double-stranded cDNA. In retroviruses and retrotransposons, this cDNA can then integrate into the host genom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Analog
A structural analog (analogue in modern traditional English; Commonwealth English), also known as a chemical analog or simply an analog, is a compound having a structure similar to that of another compound, but differing from it in respect to a certain component. It can differ in one or more atoms, functional groups, or substructures, which are replaced with other atoms, groups, or substructures. A structural analog can be imagined to be formed, at least theoretically, from the other compound. Structural analogs are often isoelectronic. Despite a high chemical similarity, structural analogs are not necessarily functional analogs and can have very different physical, chemical, biochemical, or pharmacological properties. In drug discovery, either a large series of structural analogs of an initial lead compound are created and tested as part of a structure–activity relationship study or a database is screened for structural analogs of a lead compound. Chemical analogues of il ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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