The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
P A Janssen - One of the best experts on this subject based on the ideXlab platform.
-
The antiinflammatory effects of ketoconazole. A comparative study with Hydrocortisone Acetate in a model using living and killed Staphylococcus aureus on the skin of guinea-pigs.
Journal of the American Academy of Dermatology, 1991Co-Authors: J Van Cutsem, F Van Gerven, G Cauwenbergh, F Odds, P A JanssenAbstract:Several reports have demonstrated the efficacy of topical ketoconazole in dermatologic conditions that are not exclusively related to fungi. Some basic pharmacologic studies have indicated effects of ketoconazole on cholesterol production in keratinocytes, on the 5-lipoxygenase enzyme, and on the metabolism of all-trans-retinoic acid in the skin. These observations have led to the hypothesis that topically applied ketoconazole may possess antiinflammatory properties. This hypothesis was tested in an animal model in which living and killed Staphylococcus aureus applied to the backs of guinea pigs resulted in inflammation with erythema and hyperkeratosis. Ketoconazole 0.5% or 2% was applied topically once daily in an ointment base, either as monotherapy or in combination with Hydrocortisone Acetate 1%. In addition, untreated, excipient-treated, and Hydrocortisone Acetate-treated animals were included in the study design. All groups consisted of 10 animals that were observed and scored daily up to 3 days after the experimental therapy was stopped. In the animal model involving killed bacteria (i.e., no infection), topical ketoconazole had antiinflammatory activity comparable to that of Hydrocortisone Acetate. The activity of ketoconazole on the skin of animals infected with living bacteria (i.e., active bacterial infection) was superior to that of steroid therapy, which suggests some antibacterial effect of topically applied ketoconazole. The combination therapy was highly active under both conditions. These results suggest that, apart from the known antimycotic effects of ketoconazole, this molecule might also have effects against gram-positive bacteria at the high concentrations obtained after local application.(ABSTRACT TRUNCATED AT 250 WORDS)
-
The antiinflammatory effects of ketoconazole. A comparative study with Hydrocortisone Acetate in a model using living and killed Staphylococcus aureus on the skin of guinea-pigs.
Journal of the American Academy of Dermatology, 1991Co-Authors: J Van Cutsem, F Van Gerven, G Cauwenbergh, F Odds, P A JanssenAbstract:Several reports have demonstrated the efficacy of topical ketoconazole in dermatologic conditions that are not exclusively related to fungi. Some basic pharmacologic studies have indicated effects of ketoconazole on cholesterol production in keratinocytes, on the 5-lipoxygenase enzyme, and on the metabolism of all- trans -retinoic acid in the skin. These observations have led to the hypothesis that topically applied ketoconazole may possess antiinflammatory properties. This hypothesis was tested in an animal model in which living and killed Staphylococcus aureus applied to the backs of guinea pigs resulted in inflammation with erythema and hyperkeratosis. Ketoconazole 0.5% or 2% was applied topically once daily in an ointment base, either as monotherapy or in combination with Hydrocortisone Acetate 1%. In addition, untreated, excipient-treated, and Hydrocortisone Acetate-treated animals were included in the study design. All groups consisted of 10 animals that were observed and scored daily up to 3 days after the experimental therapy was stopped. In the animal model involving killed bacteria (i.e., no infection), topical ketoconazole had antiinflammatory activity comparable to that of Hydrocortisone Acetate. The activity of ketoconazole on the skin of animals infected with living bacteria (i.e., active bacterial infection) was superior to that of steroid therapy, which suggests some antibacterial effect of topically applied ketoconazole. The combination therapy was highly active under both conditions. These results suggest that, apart from the known antimycotic effects of ketoconazole, this molecule might also have effects against gram-positive bacteria at the high concentrations obtained after local application. In addition, the antiinflammatory potential suggested by the known inhibitory effect of ketoconazole on 5-lipoxygenase activity is confirmed in this animal model and seems comparable to that of weak steroids. Finally, in this study, some effects on keratinization were observed that might be explained by reported effects of ketoconazole on cholesterol production in keratinocytes or by the inhibitory effects of the molecule on endogenous all- trans -retinoic acid.
J Van Cutsem - One of the best experts on this subject based on the ideXlab platform.
-
The antiinflammatory effects of ketoconazole. A comparative study with Hydrocortisone Acetate in a model using living and killed Staphylococcus aureus on the skin of guinea-pigs.
Journal of the American Academy of Dermatology, 1991Co-Authors: J Van Cutsem, F Van Gerven, G Cauwenbergh, F Odds, P A JanssenAbstract:Several reports have demonstrated the efficacy of topical ketoconazole in dermatologic conditions that are not exclusively related to fungi. Some basic pharmacologic studies have indicated effects of ketoconazole on cholesterol production in keratinocytes, on the 5-lipoxygenase enzyme, and on the metabolism of all-trans-retinoic acid in the skin. These observations have led to the hypothesis that topically applied ketoconazole may possess antiinflammatory properties. This hypothesis was tested in an animal model in which living and killed Staphylococcus aureus applied to the backs of guinea pigs resulted in inflammation with erythema and hyperkeratosis. Ketoconazole 0.5% or 2% was applied topically once daily in an ointment base, either as monotherapy or in combination with Hydrocortisone Acetate 1%. In addition, untreated, excipient-treated, and Hydrocortisone Acetate-treated animals were included in the study design. All groups consisted of 10 animals that were observed and scored daily up to 3 days after the experimental therapy was stopped. In the animal model involving killed bacteria (i.e., no infection), topical ketoconazole had antiinflammatory activity comparable to that of Hydrocortisone Acetate. The activity of ketoconazole on the skin of animals infected with living bacteria (i.e., active bacterial infection) was superior to that of steroid therapy, which suggests some antibacterial effect of topically applied ketoconazole. The combination therapy was highly active under both conditions. These results suggest that, apart from the known antimycotic effects of ketoconazole, this molecule might also have effects against gram-positive bacteria at the high concentrations obtained after local application.(ABSTRACT TRUNCATED AT 250 WORDS)
-
The antiinflammatory effects of ketoconazole. A comparative study with Hydrocortisone Acetate in a model using living and killed Staphylococcus aureus on the skin of guinea-pigs.
Journal of the American Academy of Dermatology, 1991Co-Authors: J Van Cutsem, F Van Gerven, G Cauwenbergh, F Odds, P A JanssenAbstract:Several reports have demonstrated the efficacy of topical ketoconazole in dermatologic conditions that are not exclusively related to fungi. Some basic pharmacologic studies have indicated effects of ketoconazole on cholesterol production in keratinocytes, on the 5-lipoxygenase enzyme, and on the metabolism of all- trans -retinoic acid in the skin. These observations have led to the hypothesis that topically applied ketoconazole may possess antiinflammatory properties. This hypothesis was tested in an animal model in which living and killed Staphylococcus aureus applied to the backs of guinea pigs resulted in inflammation with erythema and hyperkeratosis. Ketoconazole 0.5% or 2% was applied topically once daily in an ointment base, either as monotherapy or in combination with Hydrocortisone Acetate 1%. In addition, untreated, excipient-treated, and Hydrocortisone Acetate-treated animals were included in the study design. All groups consisted of 10 animals that were observed and scored daily up to 3 days after the experimental therapy was stopped. In the animal model involving killed bacteria (i.e., no infection), topical ketoconazole had antiinflammatory activity comparable to that of Hydrocortisone Acetate. The activity of ketoconazole on the skin of animals infected with living bacteria (i.e., active bacterial infection) was superior to that of steroid therapy, which suggests some antibacterial effect of topically applied ketoconazole. The combination therapy was highly active under both conditions. These results suggest that, apart from the known antimycotic effects of ketoconazole, this molecule might also have effects against gram-positive bacteria at the high concentrations obtained after local application. In addition, the antiinflammatory potential suggested by the known inhibitory effect of ketoconazole on 5-lipoxygenase activity is confirmed in this animal model and seems comparable to that of weak steroids. Finally, in this study, some effects on keratinization were observed that might be explained by reported effects of ketoconazole on cholesterol production in keratinocytes or by the inhibitory effects of the molecule on endogenous all- trans -retinoic acid.
J Sícha - One of the best experts on this subject based on the ideXlab platform.
-
Simultaneous determination of methylparaben, propylparaben, Hydrocortisone Acetate and its degradation products in a topical cream by RP-HPLC.
Journal of pharmaceutical and biomedical analysis, 2003Co-Authors: R Hájková, P Solich, J Dvorák, J SíchaAbstract:A novel reversed-phase high-performance liquid chromatographic method with UV spectrophotometric detection was developed and validated for the determination of compounds in topical cream. The method describes determination of active component Hydrocortisone Acetate (HCA), its degradation products Hydrocortisone (HC) and cortisone Acetate (occurring in formulation after long-term stability tests) and two preservatives presented in the cream-methylparaben and propylparaben, using dexamethasone as an internal standard. The chromatographic separation was performed on a 5 microm SUPELCO Discovery C18 125 x 4-mm ID column. The optimised mobile phase for separation of all the compounds consists of methanol, acetonitrile and water (15:27:58, v/v/v), with the analysis time less than 13 min. The method was applicable for routine analysis (assays and stability tests) of active compound HCA, preservatives and degradation products in pharmaceutical product--topical cream Hydrocortizone cream 1%.
Jonathan Hadgraft - One of the best experts on this subject based on the ideXlab platform.
-
Membrane transport of Hydrocortisone Acetate from supersaturated solutions; the role of polymers.
International journal of pharmaceutics, 2001Co-Authors: S.l Raghavan, A.f. Davis, B Kiepfer, S G Kazarian, Jonathan HadgraftAbstract:Permeation of Hydrocortisone Acetate (HA) from supersaturated solutions was studied across a model silicone membrane. Supersaturated solutions were prepared using the cosolvent technique with propylene glycol and water (or aqueous polymer solutions) as the cosolvents. In the absence of the polymer, the flux of HA was similar at all degrees of saturation and was not significantly different from the value obtained for a saturated solution. Flux enhancement, as a result of supersaturation, was observed with all the polymers. The flux increased with increasing polymer concentration, reached a maximum and decreased at higher polymer percentages. The amount of polymer required for maximum enhancement differed for each polymer. The decrease of flux at high polymer concentrations is attributed to changes in microviscosity and a marginal increase in solubility. The infrared spectroscopic and differential scanning calorimetry data suggest that HA-polymer interactions occurred through hydrogen bonding thus explaining the proposed mechanism of the anti-nucleant properties of the polymers.
-
Crystallization of Hydrocortisone Acetate: influence of polymers
International journal of pharmaceutics, 2001Co-Authors: S.l Raghavan, A.f. Davis, A Trividic, Jonathan HadgraftAbstract:The influence of hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), polyvinyl pyrrolidone (PVP) and polyethylene glycol (PEG400) on the crystallization of Hydrocortisone Acetate (HA) was studied. Supersaturation was created by the cosolvent technique. Spontaneous nucleation was observed when no polymer was used as the additive. In the presence of the polymer, nucleation was delayed. The nucleation time decreased with increasing supersaturation at a particular polymer concentration and increased with increasing polymer concentration at a particular supersaturation. Habit modification from a well-defined polar prismatic morphology to a wing-shaped morphology was observed when HPMC was used as the additive. The effect of PVP and PEG400 on the morphology of HA was less pronounced compared to the cellulose polymers. The mechanism of nucleation retardation by the polymers is explained in terms of association of HA with the polymer through hydrogen bonding. The growth may be inhibited by the hydrodynamic boundary layer, in which the polymers accumulate as well as by the adsorption of the polymer onto the crystal surface. The habit modification of HA by HPMC is due to different extents of adsorption on different faces of the crystal, the extent of which is dependent on the hydrogen bonding functional groups that are exposed at each face of the crystal.
-
effect of cellulose polymers on supersaturation and in vitro membrane transport of Hydrocortisone Acetate
International Journal of Pharmaceutics, 2000Co-Authors: S.l Raghavan, A.f. Davis, A Trividic, Jonathan HadgraftAbstract:Abstract A systematic investigation on the influence of two cellulose polymers, methyl cellulose (MC) and hydroxypropyl cellulose (HPMC) on supersaturation and permeation of Hydrocortisone Acetate (HA) is reported. Diffusion of HA from a 0.5% Carbopol gel across a model silicone membrane was investigated using the Franz-cell technique. At constant polymer concentration, the flux increases proportionally with the degree of saturation up to 4.8× but decreases thereafter. For a particular degree of supersaturation (4.8×), the flux increases with the concentration of polymer up to 1% and decreases at higher concentrations. The behaviour is found to be consistent with crystallisation experiments. The results suggest that optimisation of supersaturation and polymer content is necessary to achieve both high permeation rates and inherent stability.
-
Effect of supersaturation on membrane transport: 1. Hydrocortisone Acetate
International Journal of Pharmaceutics, 1991Co-Authors: A.f. Davis, Jonathan HadgraftAbstract:Abstract In vitro, the transport of Hydrocortisone Acetate across a model synthetic membrane has been investigated. Subsaturated, saturated and supersaturated solutions of Hydrocortisone Acetate, formed by mixing appropriate propylene glycol/water cosolvent systems, were studied. Transport was linearly proportional to the degree of saturation over the wide range studied. Supersaturated systems have potential application in topical drug delivery especially when release from saturated solutions is limiting.
S. C. Gupta - One of the best experts on this subject based on the ideXlab platform.
-
efficacy of Hydrocortisone Acetate hyaluronidase vs triamcinolone acetonide hyaluronidase in the treatment of oral submucous fibrosis
Indian Journal of Medical Research, 2010Co-Authors: Mangal Singh, H S Niranjan, Ravi Mehrotra, Dn Sharma, S. C. GuptaAbstract:Background & objectives Oral submucous fibrosis is a common premalignant condition caused by chewing arecanut and other irritants in various forms. Its medical treatment is not yet fully standardized, although the optimal doses of its medical treatment is in the form of Hydrocortisone Acetate combined with hyaluronidase. The problem with the prevailing treatment was injections at weekly interval. In this study we compared the efficacy of Hydrocortisone Acetate and hyaluronidase at weekly interval versus triamcinolone acetonide and hyaluronidase at 15 days interval. Methods Patients of OSMF (100) were randomly divided into two groups A and B. Group A patients received combination of Hydrocortisone Acetate (1.5 ml)/hyaluronidase (1500 IU) at weekly interval submucosally in pterygomandibular raphe, half dose on each side for 22 wk. Group B patients received combination of triamcinolone acetonide (10 mg/ml)/ hyaluronidase (1500 IU) at 15 days interval for 22 wk. Treatment outcome was evaluated on the basis of improvement in symptom score, sign score and histopathological improvement. Student's 't' test was applied for comparing the results. Results No statistically significant difference in symptom score, sign score and histopathological improvement was seen between the two groups. Interpretation & conclusion Treatment regimen of group B was more convenient to the patients because less number of visits required and cheap. No side effects were seen. A follow up study is required to see long term effects.
-
Efficacy of Hydrocortisone Acetate/hyaluronidase vs triamcinolone acetonide/hyaluronidase in the treatment of oral submucous fibrosis.
The Indian journal of medical research, 2010Co-Authors: Mangal Singh, H S Niranjan, Ravi Mehrotra, Dn Sharma, S. C. GuptaAbstract:Background & objectives Oral submucous fibrosis is a common premalignant condition caused by chewing arecanut and other irritants in various forms. Its medical treatment is not yet fully standardized, although the optimal doses of its medical treatment is in the form of Hydrocortisone Acetate combined with hyaluronidase. The problem with the prevailing treatment was injections at weekly interval. In this study we compared the efficacy of Hydrocortisone Acetate and hyaluronidase at weekly interval versus triamcinolone acetonide and hyaluronidase at 15 days interval. Methods Patients of OSMF (100) were randomly divided into two groups A and B. Group A patients received combination of Hydrocortisone Acetate (1.5 ml)/hyaluronidase (1500 IU) at weekly interval submucosally in pterygomandibular raphe, half dose on each side for 22 wk. Group B patients received combination of triamcinolone acetonide (10 mg/ml)/ hyaluronidase (1500 IU) at 15 days interval for 22 wk. Treatment outcome was evaluated on the basis of improvement in symptom score, sign score and histopathological improvement. Student's 't' test was applied for comparing the results. Results No statistically significant difference in symptom score, sign score and histopathological improvement was seen between the two groups. Interpretation & conclusion Treatment regimen of group B was more convenient to the patients because less number of visits required and cheap. No side effects were seen. A follow up study is required to see long term effects.