SciCombinator

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Concept: Ketoconazole

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Dandruff is a common complaint and is suffered by as much as half of the population at some time post puberty. The condition is characterized by the presence of flakes on the scalp and in the hair, and is often accompanied by itch. The most common treatment for dandruff is the use of shampoo formulations that contain fungistatic agents such as zinc pyrithione (ZPT) and octopirox. Whilst most antidandruff shampoos are effective in resolving the symptoms of dandruff these shampoos can often result in hair condition that is less than acceptable to consumers which can lead to a tendency for them to revert to use of a non-antidandruff shampoo. This can result in a rapid return of dandruff symptoms. The aim of this investigation was to study the impact of using a combination of antidandruff actives and silicones on the resolution of dandruff and to deliver superior sensory properties to the hair. We have demonstrated that shampoo containing the dual active system of ZPT/Climbazole deposits both active agents onto a model skin surface (VitroSkin) and reduces Malassezia furfur regrowth in vitro. Clinical evaluation of the dual active shampoo demonstrated superior efficacy and retained superiority during a regression phase where all subjects reverted to using a non-antidandruff shampoo. We have also demonstrated that it is possible to deposit silicone materials from antidandruff shampoo uniformly over both virgin and damaged hair fibres that results in smoother hair fibres (as evidenced by reduced dry friction). This combination of antidandruff agents and conditioning silicones delivered from a shampoo provides subjects with superior antidandruff efficacy and desired end sensory benefits ensuring compliance and longer term dandruff removal.

Concepts: Hair care, Silicone, Ketoconazole, Malassezia, Hair conditioner, Shampoo, Dandruff, Zinc pyrithione

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In recent years, Aspergillus species are reported frequently as aetiological agents of fungal keratitis in tropical countries such as India. Our aim was to evaluate the epidemiological features of Aspergillus keratitis cases over a 3-year period in a tertiary eye care hospital and to determine the antifungal susceptibilities of the causative agents. This study included culture proven Aspergillus keratitis cases diagnosed between September 2005 and August 2008. Data including prevalence, predisposing factors and demography were recorded, the isolates were identified by morphological and molecular methods and the minimum inhibitory concentration values of antifungal agents towards the isolates were determined by the microdilution method. Two hundred Aspergillus isolates were identified among 1737 culture proven cases. Most of the aspergilli (75%) proved to be A. flavus, followed by A. fumigatus (11.5%). Sixteen (8%) isolates belonged to species that are recently identified causative agents of mycotic keratitis. Most of the infected patients (88%) were adults ranging from 21 to 70 years of age. Co-existing ocular disease was confirmed in 16.5% of the patients. Econazole, clotrimazole and ketoconazole were notably active against A. flavus. Aspergillus keratitis is a significant problem in patients with ocular lesions in South-Indian States, warranting early diagnosis and initiation of specific antifungal therapy to improve outcome.

Concepts: Epidemiology, Aspergillus flavus, Ophthalmology, Keratitis, Aspergillus, Aspergillus fumigatus, Ketoconazole, Fungal keratitis

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We report a case of a patient infected by Candida albicans which was identified by direct extraction of DNA from a positive transparent dressing and a swab. The patient was a 32-year-old male who complained of erosion in his inguinal region. Large patches of erythema and erosion were present in his inguinal and perianal region, with soya-bean like residue discharge. He was diagnosed with erythrasma and treated with antibiotics but his clinical condition did not improve. KOH examination furnished a positive result for candidiasis. Morphologic characteristics confirmed his infection was caused by Candida albicans. Sequencing of the internal transcribed spacer (ITS) ¼ polymerase chain reaction products, amplified from positive transparent dressing and cotton swab with discharge and from primary culture isolates, established the Candida albicans lineage. The patient was cured by treatment with itraconazole 200 mg twice a day orally in combination with topical wash with 2 % ketoconazole shampoo and topical use of 1 % naftifine-0.25 % ketoconazole cream.

Concepts: DNA, Polymerase chain reaction, Molecular biology, Biotechnology, Candida albicans, DNA polymerase, Candidiasis, Ketoconazole

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Trichophyton rubrum is a worldwide agent responsible for chronic cases of dermatophytosis which have high rates of resistance to antifungal drugs. Attention has been drawn to the antimicrobial activity of aromatic compounds because of their promising biological properties. Therefore, we investigated the antifungal activity of eugenol against 14 strains of T. rubrum which involved determining its minimum inhibitory concentration (MIC) and effects on mycelial growth (dry weight), conidial germination and morphogenesis. The effects of eugenol on the cell wall (sorbitol protect effect) and the cell membrane (release of intracellular material, complex with ergosterol, ergosterol synthesis) were investigated. Eugenol inhibited the growth of 50% of T. rubrum strains employed in this study at an MIC = 256 μg/ml, as well as mycelial growth and conidia germination. It also caused abnormalities in the morphology of the dermatophyte in that we found wide, short, twisted hyphae and decreased conidiogenesis. The results of these studies on the mechanisms of action suggested that eugenol exerts antifungal effects on the cell wall and cell membrane of T. rubrum. Eugenol act on cell membrane by a mechanism that seems to involve the inhibition of ergosterol biosynthesis. The lower ergosterol content interferes with the integrity and functionality of the cell membrane. Finally, our studies support the potential use of the eugenol as an antifungal agent against T. rubrum.

Concepts: Cell membrane, Ergosterol, Antifungal drug, Trichophyton rubrum, Onychomycosis, Athlete's foot, Ketoconazole, Miconazole

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Malassezia species are frequently associated with dandruff and seborrhoeic dermatitis. The study was conducted to evaluate antifungal activities of the extracts obtained from the roots of Asparagus racemosus Willd against Malassezia furfur and M. globosa. A. racemosus roots were successively extracted with the series of solvents i.e. hexane, ethanol and water and also a saponin enriched fraction was prepared. The amounts of saponin (equivalent to shatavarin IV) in the extracts were determined by ELISA. The extracts were tested for antifungal activity by disc diffusion and broth microdilution methods. By disc diffusion, only the ethanolic and saponin enriched extracts demonstrated antifungal activity against M. furfur and M. globosa at the concentration of 1 mg/disc while the extracts with other solvents were ineffective. Multiple concentrations using the broth microdilution method against M. furfur and M. globosa yielded minimum inhibitory concentrations (MICs) of 25 mg mL(-1) for the ethanolic extract but much higher potency for the saponin enriched extract: MICs to 0.20 and 0.40 mg mL(-1) for M. furfur and M. globosa, respectively. These extracts showed no antagonist effect with the antifungal agents, ketoconazole and zinc pyrithione. Since A. racemosus is also anti-inflammatory agent, it has the potential use as an active ingredient in an anti-dandruff formulation. This article is protected by copyright. All rights reserved.

Concepts: Ethanol, Antifungal drug, Copyright, Ketoconazole, Malassezia, Seborrhoeic dermatitis, Dandruff, Zinc pyrithione

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Seborrheic dermatitis (SD) is a common skin condition seen frequently in clinical practice. The use of varying terms such as sebopsoriasis, seborrheic dermatitis, seborrheic eczema, dandruff, and pityriasis capitis reflects the complex nature of this condition. Despite its frequency, much controversy remains regarding the pathogenesis of SD. This controversy extends to its classification in the spectrum of cutaneous diseases, having being classified as a form of dermatitis, a fungal disease, or an inflammatory disease, closely related with psoriasis. Some have postulated that SD is caused by Malassezia yeasts, based on the observation of their presence in affected skin and the therapeutic response to antifungal agents. Others have proposed that Malassezia is incidental to a primary inflammatory dermatosis that resulted in increased cell turnover, scaling, and inflammation in the epidermis, similar to psoriasis. The presence of host susceptibility factors, permitting the transition of M furfur to its pathogenic form, may be associated with immune response and inflammation. Metabolites produced by Malassezia species, including oleic acid, malssezin, and indole-3-carbaldehyde, have been implicated. SD also has been traditionally considered to be a form of dermatitis based on the presence of Malassezia in healthy skin, the absence the pathogenic mycelial form of Malassezia yeasts in SD, and its chronic course. As a result, proposed treatments vary, ranging from topical corticosteroids to topical antifungals and antimicrobial peptides.

Concepts: Immune system, Inflammation, Asthma, Antifungal drug, Ketoconazole, Malassezia, Seborrhoeic dermatitis, Zinc pyrithione

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Abstract Objective: There are controversies in the treatment of seborrheic dermatitis. The aim of this study was to compare the efficacy of sertaconazole 2 % cream vs. ketoconazole 2% cream in the treatment of seborrheic dermatitis. Methods: 132 patients, with diagnosis of seborrheic dermatitis were studied. The first group received sertaconazole 2% cream (group A), and the other received ketoconazole 2% cream (group B) . At the beginning of referring and also 2 and 4 weeks after first visit, the patients were examined by a dermatologist to control improvement of clinical symptoms and drug side effects. Results: The mean age of sertaconazole and ketoconazole group was 30.18 ± 12.36 and 34.68 ± 10.16, respectively. Patients with moderate SI had the most frequency (76.6%) at pretreatment stag with ketoconazole 2% cream. This is while patients with mild SI had the highest frequency (53.3%) at post-treatment stage. In patients received the sertaconazole 2 % cream, the highest frequency was observed in 80% of cases with moderate SI at pretreatment stage while patients with slight SI had the highest frequency (83.3%) at post-treatment stage. Conclusion: Sertaconazole 2 % cream may be an excellent alternative therapeutic modality for treating seborrheic dermatitis.

Concepts: Medicine, Comparison, Comparisons, Antifungal drug, Group B, Modality, Ketoconazole, Seborrhoeic dermatitis

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A novel model of infected nail plate for testing the efficacy of topical antifungal formulations has been developed. This model utilized keratin film made of human hair keratin as a nail plate model. Subsequent to infection by T. rubrum, the common causative agent of onychomycosis, keratin films as infected nail plate models were treated with selected topical formulations, i.e., cream, gel and nail lacquer. Bovine hoof was compared to keratin film. In contrast to the common antifungal susceptibility test, the antifungal drugs tested were applied as ready-to-use formulations because the vehicle may modify and control the drug action both in vitro and in vivo. Extrapolating the potency of an antifungal drug from an in vitro susceptibility test only would not be representative of the in vivo situation since these drugs are applied as ready-to-use formulations, e.g., as a nail lacquer. Although terbinafine has been acknowledged to be the most effective antifungal agent against T. rubrum, its antifungal efficacy was improved by its incorporation into an optimal formulation. Different gels proved superior to cream. Therefore, this study is able to discriminate between efficacies of different topical antifungal formulations based on their activities against T. rubrum.

Concepts: Antifungals, Keratin, Antifungal drug, Onychomycosis, Athlete's foot, Griseofulvin, Ketoconazole, Ringworm

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Candida species are responsible for many opportunistic fungal infections. Fluconazole is a well-tolerated antifungal drug, commonly used in the treatment of Candidiasis. However, with fluconazole resistance ever increasing, rapid detection and antifungal susceptibility testing of Candida is imperative for proper patient treatment. Presented herein is a cost-effective, simple, and rapid chromogenic agar dilution method for simultaneous Candida species identification and fluconazole susceptibility testing. The results obtained by X-Plate Technology were in absolute concordance with standard microbroth dilution assays. Analysis of 1383 clinical patient samples with suspected vulvovaginal Candidiasis revealed that this technology was able to detect and speciate the Candida isolate and determine the fluconazole susceptibility. The prevalence and susceptibility profiles of the clinical isolates using this method were highly similar to published reports using the microbroth dilution method.

Concepts: Opportunistic infection, Antifungals, Candidiasis, Antifungal drug, Athlete's foot, Fluconazole, Griseofulvin, Ketoconazole

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Onychomycosis is a common fungal nail infection in adults that is difficult to treat. The in vitro antifungal activity of efinaconazole, a novel triazole antifungal, was evaluated in recent clinical isolates of T. rubrum, T. mentagrophytes and C. albicans, common causative onychomycosis pathogens. In a comprehensive survey of 1493 isolates, efinaconazole minimum inhibitory concentrations (MIC) against T. rubrum and T. mentagrophytes ranged from ≤0.002 to 0.06 μg/ml, with 90% of isolates inhibited (MIC(90)) at 0.008 and 0.015 μg/ml, respectively. Efinaconazole MICs against 105 C. albicans isolates ranged from ≤0.0005 to >0.25 μg/ml, with 50% of isolates inhibited (MIC(50)) by 0.001 and 0.004 μg/ml at 24 and 48 hours, respectively. Efinaconazole potency against these organisms was similar or greater compared to antifungal drugs currently used in onychomycosis, including amorolfine, ciclopirox, itraconazole and terbinafine. In 13 T. rubrum toenail isolates from onychomycosis patients who were treated daily with topical efinaconazole for 48 weeks, there were no apparent increases in susceptibility, suggesting low potential for dermatophytes to develop resistance to efinaconazole. The activity of efinaconazole was further evaluated in other 8 dermatophyte, 15 nondermatophyte and 10 yeast species (109 isolates total from research repositories). Efinaconazole was active against Trichophyton, Microsporum, Epidermophyton, Acremonium, Fusarium, Paecilomyces, Pseudallescheria, Scopulariopsis, Aspergillus, Cryptococcus, Trichosporon and Candida, and compared favorably to other antifungal drugs. In conclusion, efinaconazole is a potent antifungal with broad spectrum of activity that may have clinical applications in onychomycosis and other mycoses.

Concepts: Fungus, Yeast, Antifungals, Ascomycota, Antifungal drug, Onychomycosis, Athlete's foot, Ketoconazole