|
Sulfadoxine
Sulfadoxine (also spelled sulphadoxine) is an ultra-long-lasting sulfonamide used in combination with pyrimethamine to treat malaria.Medical Treatment - Sulphadoxine and Pyrimethamine . It is also used to prevent malaria but due to high levels of sulphadoxine-pyrimethamine resistance, this use has become less common. It is also used, usually in combination with other drugs, to treat or prevent various infections in livestock. Mechanism of action Sulfadoxine competitively inhibits , interfering with folate synthesis. ...
|
Sulfadoxine/pyrimethamine
Sulfadoxine/pyrimethamine, sold under the brand name Fansidar, is a combination medication used to treat malaria. It contains sulfadoxine (a sulfonamide) and pyrimethamine (an antiprotozoal). For the treatment of malaria it is typically used along with other antimalarial medication such as artesunate. In areas of Africa with moderate to high rates of malaria, three doses are recommended during the second and third trimester of pregnancy. Side effects include diarrhea, rash, itchiness, headache, and hair loss. Rarely a severe allergic reaction or rash such as toxic epidermal necrolysis, may occur. It is not generally recommended in people with a sulfonamide allergy or significant liver or kidney disease. It works by blocking malaria's ability to use folinic acid. Sulfadoxine/pyrimethamine was initially approved for medical use in the United States in 1981. It is on the World Health Organization's List of Essential Medicines. It is not commercially available in the United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrimethamine
Pyrimethamine, sold under the brand name Daraprim among others, is a medication used with leucovorin (leucovorin is used to decrease side effects of pyrimethamine; it does not have intrinsic anti-parasitic activity) to treat the parasitic diseases toxoplasmosis and cystoisosporiasis. It is also used with dapsone as a second-line option to prevent ''Pneumocystis jiroveci'' pneumonia in people with HIV/AIDS. It was previously used for malaria but is no longer recommended due to resistance. Pyrimethamine is taken by mouth. Common side effects include gastrointestinal upset, severe allergic reactions, and bone marrow suppression. It should not be used by people with folate deficiency that has resulted in anemia. There is concern that it may increase the risk of cancer. While occasionally used in pregnancy it is unclear if pyrimethamine is safe for the baby. Pyrimethamine is classified as a folic acid antagonist. It works by inhibiting folic acid metabolism and therefore the maki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. Symptoms usually begin ten to fifteen days after being bitten by an infected mosquito. If not properly treated, people may have recurrences of the disease months later. In those who have recently survived an infection, reinfection usually causes milder symptoms. This partial resistance disappears over months to years if the person has no continuing exposure to malaria. Malaria is caused by single-celled microorganisms of the ''Plasmodium'' group. It is spread exclusively through bites of infected ''Anopheles'' mosquitoes. The mosquito bite introduces the parasites from the mosquito's saliva into a person's blood. The parasites travel to the liver where they mature and reproduce. Five species of ''Plasmodium'' can infect and be spread by h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfonamide (medicine)
Sulfonamide is a functional group (a part of a molecule) that is the basis of several groups of drugs, which are called sulphonamides, sulfa drugs or sulpha drugs. The original antibacterial sulfonamides are synthetic (nonantibiotic) antimicrobial agents that contain the sulfonamide group. Some sulfonamides are also devoid of antibacterial activity, e.g., the anticonvulsant sultiame. The sulfonylureas and thiazide diuretics are newer drug groups based upon the antibacterial sulfonamides. Allergies to sulfonamides are common. The overall incidence of adverse drug reactions to sulfa antibiotics is approximately 3%, close to penicillin; hence medications containing sulfonamides are prescribed carefully. Sulfonamide drugs were the first broadly effective antibacterials to be used systemically, and paved the way for the antibiotic revolution in medicine. Function In bacteria, antibacterial sulfonamides act as competitive inhibitors of the enzyme dihydropteroate synthase (DHP ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydropteroate Synthase
Dihydropteroate synthase is an enzyme classified under . It produces dihydropteroate in bacteria, but it is not expressed in most eukaryotes including humans. This makes it a useful target for sulfonamide antibiotics, which compete with the PABA precursor. * (2-amino-4-hydroxy-7,8-dihydropteridin-6-yl)methyl diphosphate + 4-aminobenzoate (PABA) \rightleftharpoons diphosphate + dihydropteroate. All organisms require reduced folate cofactors for the synthesis of a variety of metabolites. Most microorganisms must synthesize folate de novo because they lack the active transport system of higher vertebrate cells that allows these organisms to use dietary folates. Proteins containing this domain include dihydropteroate synthase () as well as a group of methyltransferase enzymes including methyltetrahydrofolate, corrinoid iron-sulphur protein methyltransferase (MeTr) that catalyses a key step in the Wood-Ljungdahl pathway of carbon dioxide fixation. Dihydropteroate synthase () (D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethers
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be classified into two varieties: if the alkyl or aryl groups are the same on both sides of the oxygen atom, then it is a simple or symmetrical ether, whereas if they are different, the ethers are called mixed or unsymmetrical ethers. A typical example of the first group is the solvent and anaesthetic diethyl ether, commonly referred to simply as "ether" (). Ethers are common in organic chemistry and even more prevalent in biochemistry, as they are common linkages in carbohydrates and lignin. Structure and bonding Ethers feature bent C–O–C linkages. In dimethyl ether, the bond angle is 111° and C–O distances are 141 pm. The barrier to rotation about the C–O bonds is low. The bonding of oxygen in ethers, alcohols, and water is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrimidines
Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine (nitrogen atoms at the 1 and 4 positions) and pyridazine (nitrogen atoms at the 1 and 2 positions). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U). Occurrence and history The pyrimidine ring system has wide occurrence in nature as substituted and ring fused compounds and derivatives, including the nucleotides cytosine, thymine and uracil, thiamine (vitamin B1) and alloxan. It is also found in many synthetic compounds such as barbiturates and the HIV drug, zidovudine. Although pyrimidine derivatives such as alloxan were known in the early 19th century, a laboratory synthesis of a pyrimidine was not carried out until 1879, when Grimaux reported the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfonamide Antibiotics
Sulfonamide is a functional group (a part of a molecule) that is the basis of several groups of drugs, which are called sulphonamides, sulfa drugs or sulpha drugs. The original antibacterial sulfonamides are synthetic (nonantibiotic) antimicrobial agents that contain the sulfonamide group. Some sulfonamides are also devoid of antibacterial activity, e.g., the anticonvulsant sultiame. The sulfonylureas and thiazide diuretics are newer drug groups based upon the antibacterial sulfonamides. Allergies to sulfonamides are common. The overall incidence of adverse drug reactions to sulfa antibiotics is approximately 3%, close to penicillin; hence medications containing sulfonamides are prescribed carefully. Sulfonamide drugs were the first broadly effective antibacterials to be used systemically, and paved the way for the antibiotic revolution in medicine. Function In bacteria, antibacterial sulfonamides act as competitive inhibitors of the enzyme dihydropteroate synthase (DH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydropteroate Synthetase Inhibitors
Dihydropteroate is an important intermediate in folate synthesis. It is a pterin created from ''para''-aminobenzoic acid (PABA) by the enzyme dihydropteroate synthase. Bacteriostatic agents such as sulfonamides target dihydropteroate synthetase. The effect of dihydropteroate synthetase inhibition is comparable to that of dihydrofolate reductase inhibition by trimethoprim, another bacteriostatic agent. Combinations of these two drug types, such as the combination trimethoprim/sulfamethoxazole (TMP-SMX]), are commonly used to treat recurrent urinary tract, ''Shigella'', ''Salmonella'', and '' Pneumocystis jivoreci'' infections. See also * Dihydrofolic acid Dihydrofolic acid (conjugate base dihydrofolate) (DHF) is a folic acid ( vitamin B9) derivative which is converted to tetrahydrofolic acid by dihydrofolate reductase. Since tetrahydrofolate is needed to make both purines and pyrimidines, which a ... References {{reflist Benzoic acids Folates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Ethers")
