Acne is a common problem in adolescents and young adults. The disorder is caused by abnormal desquamation of follicular epithelium that results in obstruction of the pilosebaceous canal. This obstruction leads to the formation of comedones, which can become inflamed because of overgrowth of Propionibacterium acnes. Topical retinoids such as tretinoin or adapalene are effective in many patients with comedonal acne. Patients with inflammatory lesions benefit from treatment with benzoyl peroxide, azelaic acid or topical antibiotics. Frequently, the use of comedonal and antibacterial agents is required. (+info)
Inactivation of HIV-1 nucleocapsid protein P7 by pyridinioalkanoyl thioesters. Characterization of reaction products and proposed mechanism of action.
The synthesis and antiviral properties of pyridinioalkanoyl thioester (PATE) compounds that target nucleocapsid p7 protein (NCp7) of the human immunodeficiency virus type 1 (HIV-1) have been described previously (Turpin, J. A., Song, Y., Inman, J. K., Huang, M., Wallqvist, A., Maynard, A., Covell, D. G., Rice, W. G., and Appella, E. (1999) J. Med. Chem. 42, 67-86). In the present study, fluorescence and electrospray ionization-mass spectrometry were employed to determine the mechanism of modification of NCp7 by two lead compounds, N-[2-(5-pyridiniovaleroylthio)benzoyl]sulfacetamide bromide and N-[2-(5-pyridiniovaleroylthio)benzoyl]-4-(4-nitrophenylsulfonyl )anili ne bromide (compounds 45 and 47, respectively). Although both compounds exhibit antiviral activity in cell-based assays, we failed to detect appreciable ejection of zinc from NCp7 under conditions in which previously described NCp7-active disulfides readily eject zinc. However, upon "activation" by Ag(+), compound 45 reacted with NCp7 resulting in the zinc ejection from both zinc fingers. The reaction followed a two-step mechanism in which zinc was ejected from the carboxyl-terminal zinc finger faster than from the amino-terminal zinc finger. Both compounds covalently modified the protein with pyridinioalkanoyl groups. Compound 45 modified cysteines 36 and 49 of the carboxyl-terminal zinc finger. The results obtained herein demonstrate that PATE compounds can be constructed that selectively target only one of the two zinc fingers of NCp7, thus providing an impetus to pursue development of highly selective zinc finger inhibitors. (+info)
Studies on the influence of auxiliary substances on the physico-chemical characteristics of ophthalmic drugs. Part I. Studies on the influence of auxiliary substances on the critical micellar concentration of surfactants solutions in eye drops containing sulphacetamidum natricum.
Interactions between Tweens, surfactants used in eye drops and the remaining compounds of the preparations were investigated. The interactions were assessed by means of the surface tension measurement method. Obtained results demonstrate that the substances used in the facture of the preparation affect the critical micellar concentrations of Tweens. Only hydroxyethylcellulose was found to exert a stabilizing effect on the critical micellar concentration of these substances. The amount of used surfactant should be taken into consideration in the manufacture of eye preparations. (+info)
The distribution and kinetics of sulphacetamide in leukaemic mice.
1 During the first 90 min following oral administration of sulphacetamide, there was a rapid decline in plasma drug concentration in control mice whereas a progressive increase in sulphacetamide concentration was observed in leukaemic mice. 2 Similar changes in the kinetics of sulphacetamide distribution were observed in the liver, spleen and muscle. 3 While the concentration of sulphacetamide remained quite constant in the brain and fat tissue of control mice, a progressive increase in drug concentration was observed in the brain and fat tissue of leukaemic mice. 4 Some of these changes in the kinetics of sulphacetamide tissue distribution are compatible with delay in gastrointestinal absorption of the drug and its accumulation in the ascitic fluid. (+info)
EFFECT OF ACETAZOLAMIDE AND TRIPLE SULFONAMIDE ON CITRATE AND CALCIUM EXCRETION.
The administration of acetazolamide was shown to increase the excretion of calcium in both normal persons and in stone formers, while at the same time the urinary excretion of citrate was reduced. Urinary citrate is potentially of importance in chelating calcium and preventing it from precipitating. In view of the chemical similarity between acetazolamide and the sulfonamides it was considered that the latter might produce a similar effect, with potential hazard if administered to a stone former. This was shown not to be the case. (+info)
Rosacea and its topical management.
Many options exist for the treatment of rosacea, including topical and systemic therapies, laser and light-based therapies, and surgical procedures. A classification system for rosacea identifies 4 subtypes (i.e., erythematotelangiectatic, papulopustular, phymatous, and ocular), which may help guide therapeutic decision-making. The goals of therapy include reduction of papules, pustules, erythema, physical discomfort, and an improvement in quality of life. Standard topical treatment agents include metronidazole, azelaic acid, and sodium sulfacetamide-sulfur. Second line therapies include benzoyl peroxide, clindamycin, calcineurin inhibitors, and permethrin. (+info)
Sulfacetamide loaded Eudragit(R) RL100 nanosuspension with potential for ocular delivery.
PURPOSE: Polymeric nanosuspension was prepared from an inert polymer resin (Eudragit(R) RL100) with the aim of improving the availability of sulfacetamide at the intraocular level to combat bacterial infections. METHODS: Nanosuspensions were prepared by the solvent displacement method using acetone and Pluronic(R) F108 solution. Drug to polymer ratio was selected as formulation variable. Characterization of the nanosupension was performed by measuring particle size, zeta potential, Fourier Transform infrared spectra (FTIR), Differential Scanning Calorimetry (DSC), Powder X-Ray Diffraction (PXRD), drug entrapment efficiency and in vitro release. In addition, freeze drying, redispersibility and short term stability study at room temperature and at 4(0)C were performed. RESULTS: Spherical, uniform particles (size below 500 nm) with positive zeta potential were obtained. No significant chemical interactions between drug and polymer were observed in the solid state characterization of the freeze dried nanosuspension (FDN). Drug entrapment efficiency of the selected batch was increased by changing the pH of the external phase and addition of polymethyl methacrylate in the formulation. The prepared nanosuspension exhibited good stability after storage at room temperature and at 4(0)C. Sucrose and Mannitol were used as cryoprotectants and exhibited good water redispersibility of the FDN. CONCLUSION: The results indicate that the formulation of sulfacetamide in Eudragit(R) RL100 nanosuspension could be utilized as potential delivery system for treating ocular bacterial infections. (+info)
Rosacea: update on management and emerging therapies.
Rosacea is a common chronic skin disorder that has significant impact on the self-esteem and quality of life of affected individuals. Currently understood as an inflammatory condition that occurs in the context of an altered innate immune response, the available topical and systemic therapies function as immunomodulators to restore cutaneous homeostasis. The goals of therapy include reduction of papules, pustules, erythema and physical discomfort with improvement in quality of life. Standard topical treatments include metronidazole and azelaic acid, although many other agents and regimens have been presented. Subantimicrobial/antiinflammatory dose oral doxycycline was US FDA approved in 2006 for the management of rosacea, but Health Canada clearance was only recently granted for this indication. Furthermore, renewed research interest has led to the development of other emerging therapies including topical ivermectin, brimonidine and oxymetazoline that hold promise for patients suffering from this condition. (+info)