U.S. Department of Health & Human Services Divider Arrow National Institutes of Health Divider Arrow NCATS

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

    {{facet.count}}
    {{facet.count}}

Showing 901 - 910 of 1221 results

Nelfinavir is a protease inhibitor with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Protease inhibitors block the part of HIV called protease. HIV-1 protease is an enzyme required for the proteolytic cleavage of the viral polyprotein precursors into the individual functional proteins found in infectious HIV-1. Nelfinavir binds to the protease active site and inhibits the activity of the enzyme. This inhibition prevents cleavage of the viral polyproteins resulting in the formation of immature non-infectious viral particles. Protease inhibitors are almost always used in combination with at least two other anti-HIV drugs. Nelfinavir inhibits the HIV viral proteinase enzyme which prevents cleavage of the gag-pol polyprotein, resulting in noninfectious, immature viral particles. Nelfinavir is used in combination with other antiviral drugs in the treatment of HIV in both adults and children. Nelfinavir is marketed under the brand name Viracept.
Nevirapine is a non-nucleoside reverse transcriptase inhibitor (nNRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). HIV-2 RT and eukaryotic DNA polymerases (such as human DNA polymerases alpha, beta, or sigma) are not inhibited by nevirapine. Nevirapine is, in general, only prescribed after the immune system has declined and infections have become evident. It is always taken with at least one other HIV medication such as Retrovir or Videx. The virus can develop resistance to nevirapine if the drug is taken alone, although even if used properly, nevirapine is effective for only a limited time. Nevirapine binds directly to reverse transcriptase (RT) and blocks the RNA-dependent and DNA-dependent DNA polymerase activities by causing a disruption of the enzyme's catalytic site. The activity of nevirapine does not compete with template or nucleoside triphosphates. Nevirapine is used for use in combination with other antiretroviral drugs in the ongoing treatment of HIV-1 infection.
Status:

Class (Stereo):
CHEMICAL (ACHIRAL)



Titanium dioxide, also known as titanium(IV) oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO 2. When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. Generally it is sourced from ilmenite, rutile and anatase. It has a wide range of applications, from paint to sunscreen to food coloring. When used as a food coloring, it has E number E171. World production in 2014 exceeded 9 million metric tons. Titanium dioxide has excellent ultraviolet (UV) resistant qualities and acts as a UV absorbent. In the pharmaceutical industry, titanium dioxide is used in most sunscreens to block UVA and UVB rays, similar to zinc oxide. It is also commonly used as pigment for pharmaceutical products such as gelatin capsules, tablet coatings and syrups. In the cosmetics industry, it is used in toothpaste, lipsticks, creams, ointments and powders. It can be used as an opacifier to make pigments opaque. The FDA has approved the safety of titanium dioxide for use as a colorant in food, drugs and cosmetics, including sunscreens. However, controversy exists as to the safety of titanium dioxide nanoparticles used in the cosmetics industry, for example in sunscreens. Titanium and zinc oxides may be made into the nanoparticle size (0.2-100 nanometers) to reduce the white appearance when applied topically, but retain the UV blocking properties. Recent studies suggest titanium dioxide nanoparticles may be toxic, although further research is needed.
Status:

Class (Stereo):
CHEMICAL (RACEMIC)


Conditions:

Mefloquine, sold under the brand names Lariam among others, is a medication used to for the treatment of mild to moderate acute malaria caused by Mefloquineuine-susceptible strains of Plasmodium falciparum (both chloroquine-susceptible and resistant strains) or by Plasmodium vivax. Also for the prophylaxis of Plasmodium falciparum and Plasmodium vivax malaria infections, including prophylaxis of chloroquine-resistant strains of Plasmodium falciparum. Mefloquine acts as a blood schizonticide. Mefloquine is active against the erythrocytic stages of Plasmodium species. However, the drug has no effect against the exoerythrocytic (hepatic) stages of the parasite. Mefloquine is effective against malaria parasites resistant to chloroquine. Mefloquine is a chiral molecule. According to some research, the (+) enantiomer is more effective in treating malaria, and the (-) enantiomer specifically binds to adenosine receptors in the central nervous system, which may explain some of its psychotropic effects.
Status:
First approved in 1987

Class (Stereo):
CHEMICAL (ACHIRAL)



Mesna is an organosulfur compound used as an adjuvant in cancer chemotherapy involving cyclophosphamide and ifosfamide. No clinical drug interaction studies have been conducted with mesna. Mesna concentrates in the bladder where acrolein accumulates after administration of chemotherapy and through a Michael addition, forms a conjugate with acrolein and other urotoxic metabolites. This conjugation reaction inactivates the urotoxic compounds to harmless metabolites. The most common adverse reactions (> 10%) when MESNEX is given with ifosfamide are nausea, vomiting, constipation, leukopenia, fatigue, fever, anorexia, thrombocytopenia, anemia, granulocytopenia, diarrhea, asthenia, abdominal pain, headache, alopecia, and somnolence.
Ciprofloxacin (1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid) is the synthetic antimicrobial agent for oral or intravenous administration. Ciprofloxacin is a member of the fluoroquinolone class of antibacterial agents. The bactericidal action of ciprofloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV (both Type II topoisomerases), which are required for bacterial DNA replication, transcription, repair, and recombination. Ciprofloxacin is used to treat a wide variety of infections, including infections of bones and joints, endocarditis, gastroenteritis, malignant otitis externa, respiratory tract infections, cellulitis, urinary tract infections, prostatitis, anthrax, and chancroid. In the United States, ciprofloxacin is pregnancy category C. This category includes drugs for which no adequate and well-controlled studies in human pregnancy exist, and for which animal studies have suggested the potential for harm to the fetus, but potential benefits may warrant use of the drug in pregnant women despite potential risks. Fluoroquinolones have been reported as present in a mother's milk and thus passed on to the nursing child. Oral and intravenous ciprofloxacin is approved by the FDA for use in children for only two indications due to the risk of permanent injury to the musculoskeletal system: Inhalational anthrax (postexposure) and Complicated urinary tract infections and pyelonephritis due to Escherichia coli.
Pentamidine (formulated as a salt, pentamidine diisethionate or dimesilate) is an antimicrobial medication given for prevention and treatment of pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii (formerly known as Pneumocystis carinii), a severe interstitial type of pneumonia often seen in patients with HIV infection. The drug is also the mainstay of treatment for stage I infection with Trypanosoma bruceigambiense (West African trypanosomiasis). Pentamidine is also used as a prophylactic against PCP in patients receiving chemotherapy and in some patients who have undergone organ transplantation, as they also have a depressed immune system as a direct side-effect of the drugs used. The mortality of untreated PCP is very high. Additionally, pentamidine has good clinical activity in treating leishmaniasis, and yeast infections caused by the organism Candida albicans. Pentamidine is also used as a prophylactic antibiotic for children undergoing treatment for leukemia. Studies suggest that the pentamidine isethionate interferes with microbial nuclear metabolism by inhibition of DNA, RNA, phospholipid and protein synthesis. However, the mode of action is not fully understood.
Pentamidine (formulated as a salt, pentamidine diisethionate or dimesilate) is an antimicrobial medication given for prevention and treatment of pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii (formerly known as Pneumocystis carinii), a severe interstitial type of pneumonia often seen in patients with HIV infection. The drug is also the mainstay of treatment for stage I infection with Trypanosoma bruceigambiense (West African trypanosomiasis). Pentamidine is also used as a prophylactic against PCP in patients receiving chemotherapy and in some patients who have undergone organ transplantation, as they also have a depressed immune system as a direct side-effect of the drugs used. The mortality of untreated PCP is very high. Additionally, pentamidine has good clinical activity in treating leishmaniasis, and yeast infections caused by the organism Candida albicans. Pentamidine is also used as a prophylactic antibiotic for children undergoing treatment for leukemia. Studies suggest that the pentamidine isethionate interferes with microbial nuclear metabolism by inhibition of DNA, RNA, phospholipid and protein synthesis. However, the mode of action is not fully understood.
Nifedipine has been formulated as both a long- and short-acting 1,4-dihydropyridine calcium channel blocker. Nifedipine is sold under the brand names Adalat and Procardia among others. Nifedipine decreases arterial smooth muscle contractility and subsequent vasoconstriction by inhibiting the influx of calcium ions through L-type calcium channels. Calcium ions entering the cell through these channels bind to calmodulin. Calcium-bound calmodulin then binds to and activates myosin light chain kinase (MLCK). Activated MLCK catalyzes the phosphorylation of the regulatory light chain subunit of myosin, a key step in muscle contraction. Signal amplification is achieved by calcium-induced calcium release from the sarcoplasmic reticulum through ryanodine receptors. Inhibition of the initial influx of calcium inhibits the contractile processes of smooth muscle cells, causing dilation of the coronary and systemic arteries, increased oxygen delivery to the myocardial tissue, decreased total peripheral resistance, decreased systemic blood pressure, and decreased afterload. The vasodilatory effects of nifedipine result in an overall decrease in blood pressure. Nifedipine is used for the management of vasospastic angina, chronic stable angina, hypertension, and Raynaud's phenomenon. May be used as a first line agent for left ventricular hypertrophy and isolated systolic hypertension (long-acting agents).
Amiloride, an antikaliuretic-diuretic agent, is a pyrazine-carbonyl-guanidine that is unrelated chemically to other known antikaliuretic or diuretic agents. It is an antihypertensive, potassium-sparing diuretic that was first approved for use in 1967 and helps to treat hypertension and congestive heart failure. The drug is often used in conjunction with thiazide or loop diuretics. Due to its potassium-sparing capacities, hyperkalemia (high blood potassium levels) are occasionally observed in patients taking amiloride. Amiloride works by inhibiting sodium reabsorption in the distal convoluted tubules and collecting ducts in the kidneys by binding to the amiloride-sensitive sodium channels. This promotes the loss of sodium and water from the body, but without depleting potassium. It is used for as adjunctive treatment with thiazide diuretics or other kaliuretic-diuretic agents in congestive heart failure or hypertension.