Concentrations Of Ketoconazole Research Articles

Photodynamic inactivation strategies for maximizing antifungal effect against Sporothrix spp. and Candida albicans in an in vitro investigation.

Sporotrichosis is a zoonotic disease caused by the dimorphic fungus Sporothrix spp., leading to skin lesions that can, in some cases, progress and result in the death of infected individuals. Candida albicans is another fungus involved in several skin, oral, and vaginal mucosal infections. Fungal diseases are concerning due to increasing incidence and the limited variety of antifungal classes available for treatment. Furthermore, antifungal medications can cause various side effects, exacerbated by their prolonged use during infection treatment. There is a need to explore alternatives to conventional drugs that are effective, fast, and safe in combating sporotrichosis. This study aimed to achieve in vitro elimination of the fungi Sporothrix brasiliensis and Sporothrix schenckii through Photodynamic Inactivation (PDI), using curcumin as a photosensitizer and in combination with antifungal agents used in the treatment of sporotrichosis. Yeasts of Candida albicans, Sporothrix brasiliensis, and Sporothrix schenckii were subjected to Photodynamic Inactivation (PDI) using light at a wavelength of 450 ± 10 nm, irradiance of 35 mW/cm2, delivering a fluence of 31.5 J/cm2, with curcumin as the photosensitizer at doses ranging from 0.75 to 150 μg/mL. After determining the Minimum Inhibitory Concentration (MIC) values of the antifungal drugs itraconazole, ketoconazole, and potassium iodide, sub-MIC doses of these antifungals were combined with sub-MIC doses of curcumin in a new PDI session. Photodynamic inactivation is a promising technique in the treatment of sporotrichosis, as well as its combination with antifungals. The combination of curcumin in concentrations ranging from 0.75 g/mL a 7.5 g/mL with sub-MIC concentrations of itraconazole, ketoconazole, and potassium iodide was able to completely inactivate the fungi C. albicans, S. brasiliensis and S. schenckii, indicating that PDI may increase the effectiveness of antifungals. However, further studies are needed to establish protocols for future clinical applications.

Ketoconazole induces reversible antifungal drug tolerance mediated by trisomy of chromosome R in Candida albicans.

The emergence of tolerance to antifungal agents in Candida albicans complicates the treatment of fungal infections. Understanding the mechanisms underlying this tolerance is crucial for developing effective therapeutic strategies. This study aims to elucidate the genetic and molecular basis of ketoconazole tolerance in C. albicans, focusing on the roles of chromosomal aneuploidy, Hsp90, and calcineurin. The wild-type C. albicans strain SC5314 was exposed to increasing concentrations of ketoconazole (0.015-32 μg/mL) to select for tolerant adaptors. Disk diffusion and spot assays were used to assess tolerance. Whole-genome sequencing identified chromosomal changes in the adaptors. The roles of Hsp90 and calcineurin in maintaining and developing ketoconazole tolerance were investigated using specific inhibitors and knockout strains. Adaptors exhibited tolerance to ketoconazole concentrations up to 16 μg/mL, a significant increase from the parent strain's inhibition at 0.015 μg/mL. All tolerant adaptors showed amplification of chromosome R, with 29 adaptors having trisomy and one having tetrasomy. This aneuploidy was unstable, reverting to euploidy and losing tolerance in drug-free conditions. Both Hsp90 and calcineurin were essential for maintaining and developing ketoconazole tolerance. Inhibition of these proteins resulted in loss of tolerance. The efflux gene CDR1 was not required for the development of tolerance. Chromosome R trisomy and tetrasomy induce cross-tolerance to other azole antifungal agents, including clotrimazole and miconazole, but not to other antifungal classes, such as echinocandins and pyrimidines, exemplified by caspofungin and 5-flucytosine. Ketoconazole tolerance in C. albicans is mediated by chromosomal aneuploidy, specifically chromosome R amplification, and requires Hsp90 and calcineurin. These findings highlight potential targets for therapeutic intervention to combat antifungal tolerance and improve treatment outcomes.

Antifungal activity of Durio zibethinus Murray peel extract against Candida albicans: A preliminary study.

The incidence of antifungal resistance to Candida albicans infections has been growing over the past years; therefore, innovations are required to develop medicinal plants with antifungal properties such as durian fruit peels (Durio zibethinus Murray) that contain significant of bioactive compounds with antifungal properties. The aim of this study was to determine the antifungal activity of D. zibethinus fruit peel extract against C. albicans by analyzing the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). A post-test only control group experiment was conducted from July to October 2020. D. zibethinus peel was collected from Simalungun Regency, Medan, Indonesia, and extracted by maceration technique using 70% ethanol to obtain D. zibethinus peel ethanol extract (DPEE). Samples of C. albicans were obtained from the Laboratory of Microbiology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. The diffusion method was used to determine the antifungal activity. Six groups with different concentrations of DPEE (6.25%, 12.5%, 25%, and 50%), ketoconazole (positive control) and dimethyl sulfoxide (negative control) were exposed to C. albicans in six replicates. Six lower concentrations (12.5%, 6.25%, 3.12%, 3%, 1.56%, and 0.78%) were divided to perform the liquid dilution method to obtain the MIC and affirmation test for MBC. The diameter of the inhibition zone was analyzed using one-way ANOVA and the Tukey post-hoc test for differences between concentrations. Our data indicated that the DPEE 6.25% had the largest inhibition zone (17.26±5.64 mm) and the inhibition zones were significant different among concentrations of DPEE (p<0.05). Furthermore, the DPEE had a MIC of 0.78% and MBC of 3.125% against C. albicans. This study highlights that the ethanol extract of D. zibethinus has potential antifungal activity against C. albicans. However, a further study is needed to determine its antifungal activities in more precise manner.

Revisiting Supersaturation of a Biopharmaceutical Classification System IIB Drug: Evaluation via a Multi-Cup Dissolution Approach and Molecular Dynamic Simulation.

As a subclass of the biopharmaceutical classification system (BCS) class II, basic drugs (BCS IIB) exhibit pH-dependent solubility and tend to generate supersaturation in the gastrointestinal tract, leading to less qualified in vitro-in vivo correlation (IVIVC). This study aims to develop a physiologically based multi-cup dissolution approach to improve the evaluation of the supersaturation for a higher quality of IVIVC and preliminarily explores the molecular mechanism of supersaturation and precipitation of ketoconazole affected by Polyvinylpyrrolidone-vinyl acetate copolymer (PVPVA) and hydroxypropyl methyl-cellulose (HPMC). The concentration of ketoconazole in each cup of the dynamic gastrointestinal model (DGIM) was measured using fiber optical probes. Molecular interactions between ketoconazole and PVPVA or HPMC were simulated by Materials Studio. The results demonstrated that PVPVA and HPMC improved and maintained the supersaturation of ketoconazole. PVPVA exhibited superior precipitation inhibitory effect on ketoconazole molecule aggregation due to slightly stronger van der Waals forces as well as unique electrostatic forces, thereby further enhancing in vitro drug absorption, which correlated well with in vivo drug absorption. Compared with a conventional dissolution apparatus paddle method, the DGIM improved the mean prediction error through the IVIVC from 19.30% to 9.96%, reaching the qualification criteria. In conclusion, the physiologically based multi-cup dissolution approach enables improved evaluation of supersaturation in gastrointestinal transportation of BCS IIB drug ketoconazole, enabling screening screen precipitation inhibitors and achieving qualified IVIVC for drug formulation studies.

The effects of degree and duration of supersaturation on in vivo absorption profiles for highly permeable drugs, dipyridamole and ketoconazole

The prediction of oral absorption from a supersaturating drug delivery system (SDDS) remains a significant challenge. Here we evaluated the effects of the degree and duration of supersaturation on in vivoabsorption for dipyridamole and ketoconazole. Various dose concentrations of supersaturated suspensions were prepared by a pH shift method, and in vitro dissolution and in vivo absorption profiles were determined. For dipyridamole, the duration of supersaturation decreased with the increase of the dose concentration owing to rapid precipitation. For ketoconazole, the initially constant dissolved concentrations due probably to the liquid–liquid phase separation (LLPS) as a reservoir were observed at high dose concentrations. However, the LLPS did not delay the peak plasma concentration of ketoconazole in rats, indicating that drug molecules were immediately released from the oil phase to the bulk aqueous phase. For both model drugs, the degree of supersaturation, but not the duration of supersaturation, correlated with systemic exposure, indicating quick drug absorption before precipitation. Therefore, the degree of supersaturation is an important parameter compared with the duration of supersaturation for enhancing the in vivo absorption of highly permeable drugs. These findings would help develop a promising SDDS.

Effectiveness of Bitter melon (Momordica charantia L) Extract on Growth of Trichopyton rubrum: In Vitro Study

Trichophyton rubrum is type of fungus that most often causes superficial fungal infections. Development of herbal ingredients as antifungal therapy is carried out to find alternative therapies for fungal infections. Bitter melon contains various compounds that have potential to be used as antifungals, including flavonoids and saponins. The aim of this study was to determine the effect of bitter melon extract (Momordica charantia L) on the growth of Trichopyton rubrum. This study used bitter melon extract at concentrations of 5%, 25%, 50%, 75% and 100%. Ketoconazole concentrations of 2% was used as a positive control. Pure cultures of Trichopyton rubrum were diluted using physiological NaCl. Fungal growth was observed microscopically and macroscopically. Results showed that Trichopyton rubrum grew at a concentration of 5% while at concentrations of 25%, 50%, 75% and 100% there was no Trichopyton rubrum growth. Bitter melon extract at a concentration of 25% had similar effect as ketoconazole 2%. Conclusion Bitter melon extract at concentrations of 25%, 50%, 75% and 100% had a similar effect to 2% ketoconazole in inhibiting the growth of Tricophyton rubrum.

Toxicological effects caused by environmental relevant concentrations of ketoconazole in Chironomus sancticaroli (Diptera, Chironomidae) larvae evaluated by oxidative stress biomarkers

Ketoconazole (KTZ), a broad-spectrum fungicidal drug, has been a significant problem in recent decades due to its toxic action on non-target aquatic organisms. Thus, the present study aimed to evaluate determine the effects that environmental relevant concentration of the commercial formulation of KTZ can exert on benthic macroinvertebrates, more specifically on larvae of the insect Chironomus sancticaroli. Acute toxicity tests with KTZ indicated lethal concentration (LC50) of 9.9 μg/L. Analyses of prolonged exposure to KTZ (chronic toxicity) indicated an increase in the rate of mentum deformity by approximately 3 times at concentrations of 0.6 and 2.4 μg/L. All biomarkers analyzed showed an increase after exposure to KTZ (0.6 and 2.4 μg/L), with average values of 115 % for superoxide dismutase (SOD), 63 % for catalase (CAT), 111 % for glutathione S-transferase (GST) and 59 % for malonaldehyde (MDA) in C. sancticaroli larvae. Thus, the toxic effects on survival, development (length and weight), mentum and redox responses caused by commercial KTZ in low concentrations were observed on C. sancticaroli larvae. In addition, the results suggest that biochemical biomarkers can be used for studies involving environmental disturbances.

Japonamides A and B, Two New Cyclohexadepsipeptides from the Marine-Sponge-Derived Fungus Aspergillus japonicus and Their Synergistic Antifungal Activities

Two new cyclohexadepsipeptides japonamides A (1) and B (2) were isolated from the ethyl acetate extract of a marine-sponge-derived fungus Aspergillus japonicus based on molecular networking. Their structures were elucidated by comprehensive spectral analysis and their absolute configurations were confirmed by Marfey’s method. Compounds 1 and 2 showed no antifungal activities against Candida albicans SC5314 measured by the broth microdilution method but exhibited prominent synergistic antifungal activities in combination with fluconazole, ketoconazole, or rapamycin. The Minimum inhibitory concentrations (MICs) of rapamycin, fluconazole, and ketoconazole were significantly decreased from 0.5 to 0.002 μM, from 0.25 to 0.063 μM, and from 0.016 to 0.002 μM, in the presence of compounds 1 or 2 at 3.125 μM, 12.5 μM, and 6.25 μM, respectively. Surprisingly, the combination of compounds 1 or 2 with rapamycin showed a strong synergistic effect, with fractional inhibitory concentration index (FICI) values of 0.03.

Molecular Typing of Dermatophytes Isolated from Pupils and Staff Members of Some Selected Schools in Anambra State, Nigeria

Dermatophytes are the fungal pathogens of human and animals infecting the keratinized tissues of the body namely skin, hair and nails. They include species of Trichophyton, Microsporum and Epidermophyton. This study was aimed at molecular typing of dermatophytes isolated from school pupils and staff members of some selected Schools in Anambra East and Ayamelum L.G.As of Anambra State in Nigeria. One thousand (1000) samples (scalp/hair, nail, feet, glabrous skin and groin/perianal) were collected from pupils and staff members of both gender and age bracket of (1 to 10, 11 to 20, 21 to 30 etc ) years that showed visible signs of skin infection located in these two Local Government Areas. Standard procedures were employed in processing of test samples and inoculation on dermatophyte test medium. The plates were incubated at room temperature (25 – 270C) for 7 – 10days for observation of fungal growth. Colonial, morphology, and molecular studies and sequencing were used for identification. Sensitivity was performed using sterilized discs (6mm) prepared from whatman No. 1 filter paper, impregnanted with different concentrations (25mg, 50mg, 100mg and 200mg) of terbinafine, itraconazole, ketoconazole, fluconazole and griseofulvin dissolved in 2% dimethylsuphuroxide (DMSO). Molecular studies were used as confirmatory tests on dermatophytic isolates using Sanger sequencing method. The results show that the dermatophytic isolates includes: Trichophyton tonsurans, Microsporum audounii, Trichophyton rubrum, Microsporum canis, Trichophyton violaceum, Trichophyton verrucosum, Trichophyton mentagrophytes, and Epidermorphyton flocossum. Results also revealed the nucleotide sequences of the dermatophytes and genetic relationships between isolated dermatophytes from different pupils and schools. PCR-RFLP was used as gold standard for the diagnosis and Confirmation of Source of infection of dermatophytes and can aid in initiating prompt and appropriate antifungal therapy. Phylogenetic tree was drawn to show the relationships between the isolates.

Ketoconazole Reverses Imatinib Resistance in Human Chronic Myelogenous Leukemia K562 Cells.

Chronic myeloid leukemia (CML) is a hematologic disorder characterized by the oncogene BCR-ABL1, which encodes an oncoprotein with tyrosine kinase activity. Imatinib, a BCR-ABL1 tyrosine kinase inhibitor, performs exceptionally well with minimal toxicity in CML chemotherapy. According to clinical trials, however, 20–30% of CML patients develop resistance to imatinib. Although the best studied resistance mechanisms are BCR-ABL1-dependent, P-glycoprotein (P-gp, a drug efflux transporter) may also contribute significantly. This study aimed to establish an imatinib-resistant human CML cell line, evaluate the role of P-gp in drug resistance, and assess the capacity of ketoconazole to reverse resistance by inhibiting P-gp. The following parameters were determined in both cell lines: cell viability (as the IC50) after exposure to imatinib and imatinib + ketoconazole, P-gp expression (by Western blot and immunofluorescence), the intracellular accumulation of a P-gp substrate (doxorubicin) by flow cytometry, and the percentage of apoptosis (by the Annexin method). In the highly resistant CML cell line obtained, P-gp was overexpressed, and the level of intracellular doxorubicin was low, representing high P-gp activity. Imatinib plus a non-toxic concentration of ketoconazole (10 μM) overcame drug resistance, inhibited P-gp overexpression and its efflux function, increased the intracellular accumulation of doxorubicin, and favored greater apoptosis of CML cells. P-gp contributes substantially to imatinib resistance in CML cells. Ketoconazole reversed CML cell resistance to imatinib by targeting P-gp-related pathways. The repurposing of ketoconazole for CML treatment will likely help patients resistant to imatinib.

Toxicological Effects Caused by Sub-Lethal Concentrations of Ketoconazole in Chironomus Sancticaroli (Diptera, Chironomidae) Larvae Evaluated by Oxidative Stress Biomarkers

Toxicological Effects Caused by Sub-Lethal Concentrations of Ketoconazole in Chironomus Sancticaroli (Diptera, Chironomidae) Larvae Evaluated by Oxidative Stress Biomarkers

Effects of ketoconazole on physiological function of liver and testis in mice

Objective: To investigate the effects of different doses of ketoconazole (KCZ) on the physiological functions of the liver and testis in Kunming mice. Methods: Forty male Kunming mice were randomly divided into four groups (n=10): normal group, KCZ low-dose group (30 mg/kg), medium-dose group (50 mg/kg), and high-dose group (70 mg/kg). The mice in the drug groups were injected subcutaneously (0.1 ml/10 g) with the corresponding dose of KCZ once a day, and the concentrations of KCZ in the KCZ low, middle, and high dose groups were 3 mg/ml, 5 mg/ml and 7 mg/ml respectively, and the normal group was injected with the same amount of normal saline for 3 weeks. The activities of aspartate transaminase (AST) and alanine aminotransferase (ALT) in serum, and γ-glutamyl transpeptidase (γ-GT), lactate dehydrogenase (LDH) and acid phosphatase (ACP) in testicular tissue were measured. HE staining was used to observe the pathological changes of the liver and testis. Results: Compared with the normal group, the activities of AST and ALT were increased significantly (P＜0.01), and the activities of γ-GT, ACP and LDH were decreased markedly in KCZ groups (P＜0.01). KCZ could affect the above indexes in a dose-dependent manner. HE staining showed that the hepatocytes were denatured, arranged loosely, and the cytoplasm was light in color. The lumen of the seminiferous tubules of the testis were enlarged, and the number of spermatogenic cells and sperm at all levels were decreased. Conclusion: KCZ could cause physiological function damage and pathological histological changes of the liver and testis, increase the levels of liver transaminase, reduce the activities of testicular specific enzymes of mice. Besides, the degree of damage was increased with the increase of dose.

Ecotoxicological effect of ketoconazole on the antioxidant system of Daphnia similis

The occurrence of emerging pharmaceutical pollutants (i.e. small drugs, antibiotics) present in aquatic environments shown to be a current environmental problem still without apparent solution. In this regard, the use of ecotoxicological techniques has been shown fundamental for the appraisal of damage to affected living organisms. Herein, ecotoxicological tests were conducted, focusing on the evaluation of the effects of ketoconazole (KTZ) on the antioxidant system of the model body Daphnia similis. In order to study the biochemical changes caused by KTZ in the antioxidant system, the enzymatic biomarkers glutathione S-transferase (GST), catalase (CAT), and ascorbate peroxidase (APX) were monitored. Toxicological tests were conducted using KTZ concentrations (0–10 μg·L−1). Prolonged exposure to KTZ (336 h) caused changes upon the expression of antioxidant enzymes and simultaneously affected the reproductive system in those organisms. Moreover, a decrease in GST and APX activity was observed caused by KTZ exposure, respectively 79.2% (3.53 μmol min−1 mg−1 protein) and 24.4% (0.88 μmol min−1 mg−1 protein). On the other hand, it was observed an increase of 27% (0.17 μmol min−1 mg−1 protein) in CAT activity. Through this study, it was possible to observe the toxicological effects of KTZ, which proves its action as an oxidative stress-inducing agent and endocrine modifier in daphnids organisms.

Simultaneous determination the concentration change of ketoconazole and dexamethasone acetate: application to drug-drug interaction in human keratinocyte

BackgroundThe combination of ketoconazole and dexamethasone acetate is one of the commonly used treatments in dermatology regiment for skin inflammation accompanied by fungal infections. This interaction of ketoconazole and dexamethasone may make the drug much effective, decrease the adverse reaction or toxic effects. At present, there was no information about the interaction of these two external drugs. Therefore, it was necessary to build a model to measure the levels and evaluate the interaction of ketoconazole and dexamethasone acetate in skin cells. MethodsIn our study, the determination methodology of ketoconazole and dexamethasone acetate in human keratinocyte (HaCaT cells) was established and the interaction of these two drugs in cells was explored. HaCaT cells were cultured in medium containing ketoconazole, then they were sequentially cultured with or without dexamethasone acetate treatment for another 1, 2, 4, 8 and 12 h. The samples were then harvested and the concentrations were quantified by enhanced BCA (the bicinchoninic acid) protein assay. Furthermore, the analytes in the cell suspension were also prepared and analyzed by LC-MS method. ResultsAs a result, ketoconazole and dexamethasone acetate were detected at the concentration range of 0.02 to 5 μg/mL and 0.2 to 100 μg/mL, respectively. The RSD (relative standard deviation) and RE (relative error) of precision and accuracy of the two analytes in the cell suspension were all less than 15 %. The matrix effect values variations were all less than 15%. The results showed that there was no significant difference in the concentration of ketoconazole with or without dexamethasone acetate treatment within 12 h. ConclusionsA simple, sensitive and rapid LC-MS method which could quantify these two analytes in cells simultaneously was developed for the first time. The results of the concentration changes meant that no interaction occurred when dexamethasone sequentially administrated for 12 h after ketoconazole treatment. This method was successfully applied to establish the cell pharmacokinetics methodology and preliminary studied the metabolism of drug-drug interaction of ketoconazole and dexamethasone acetate.

Non Detection of &amp;lt;i&amp;gt;Candida nivariensis&amp;lt;/i&amp;gt; and &amp;lt;i&amp;gt;Candida bracarensis&amp;lt;/i&amp;gt; Among &amp;lt;i&amp;gt;Candida glabrata&amp;lt;/i&amp;gt; Sensu Lato Isolates in the West Region of Cameroon

No study in Cameroon has been undertaken to check for the presence of the cryptic species belonging to the <i>Candida glabrata</i> complex, which have varying antifungal susceptibility profiles. In this regard, we analyzed a collection of 54 clinical isolates of <i>C. glabrata</i> sensu lato obtained from 1551 samples of 490 participants. These participants included 80 diabetic patients, 323 HIV-infected subjects, 73 pregnant women and 14 of some other patients who had none of the aforementioned conditions. Our study aimed at identifying <i>Candida glabrata</i> cryptic species among clinical isolates of <i>Candida glabrata</i> sensu lato from the West region of Cameroon and to evaluate their susceptibility pattern to some antifungals. Conventional tests such as culture on CHROMagar™ <i>Candida</i>, germ tube formation and chlamydospore formation tests were used for the 1^st line identification of our isolates, while the matrix assisted laser desorption ionisation – time of flight mass spectrometry (MALDI-TOF) was used for second line identification and confirmation of identifications. The minimal inhibitory concentrations (MICs) of Ketoconazole (Sigma Aldrich, China), Nystatine (Sigma Aldrich, China), Amphotericin B (Dominique Dutscher), Itraconozole (Sigma Aldrich, China), Voriconazole (Acros organics, China), and Clotrimazole (Acros organics, China) vis-à-vis 43 isolates, were determined according to the protocol proposed by the Clinical and Laboratory Standards Institute (CLSI) M27-A3 and M27-S4, with slight modifications. Of the 54 isolates, none was identified as <i>C. nivariensis</i> or <i>C. bracarensis</i> by MALDI-TOF, all the 54 (100%) isolates were confirmed to be <i>C. glabrata</i> stricto sensu. CLO (MIC range: 0.25 - >4 µg/mL) was most resisted by our isolates (95.35%), while 32.56% were resistant to KET (range of MICs: 0.03 - >4 µg/mL). On the other hand, ECVs showed that AMB (MIC range: 0.03 - 4 µg/mL) and ICZ (MIC range: 0.25 - 4 µg/mL) had very good activities against our isolates, as 81.4% of the isolates were wild type for both antifungals. On the other hand, VOR (range of MICs: 0.125 - >4 µg/mL) showed a poor activity, as most of our isolates (93.02%) were non-wild type for the antifungal. The number of isolates used in this study was not enough to conclude that <i>C. nivariensis</i> and <i>C. bracarensis</i> isolates are absent in the West Region or other parts of Cameroon, so we recommend that more of such studies be carried out in Cameroon, as this could help detect the presence of any of these emerging species with varying antifungal susceptibility profiles.

Application of an automated small-scale in vitro transfer model to predict in vivo precipitation inhibition.

The majority of NCEs are weakly basic drugs. Consequently, their solubility is highly pH-dependent, with higher solubility in the acidic stomach and poor solubility in the neutral intestinal environment. The gastric emptying of dissolved drug can lead to the intestinal precipitation of the drug. One option of reducing this process is to formulate the drug together with a precipitation inhibitor (PI). The aim of this study was to investigate the effects of different PIs on the intestinal concentrations of ketoconazole and five orally administered kinase inhibitors (i.e. pazopanib, gefitinib, lapatinib, vemurafenib, and a Merck KGaA research compound, MSC-A) with the aid of a predictive small-scale in vitro transfer model. This screening revealed that HPMCAS and Soluplus® were the most effective PIs. Whereas all other drugs precipitated within several minutes, gefitinib expressed highly variable amorphous precipitation which was confirmed by PXRD. During the transfer model experiments, this intermediate supersaturated state was stabilized using HPMCAS and Soluplus®. The PI screening protocol described herein allows to study the effect of PIs for solubility and potential bioavailability improvement of poorly soluble drugs to support formulation development already in early stages.

ANTI-CANDIDA ALBICANS ACTIVITY OF THE ASSOCIATION OF CITRONELAL WITH ANFOTERICIN B OR WITH CETOCONAZOLE

Fungal infections caused by species of the genus Candida are responsible for high morbidity and mortality rates, mainly affecting immunocompromised individuals. Among fungi, Candida albicans is the most frequently isolated species of clinical specimens. A problem associated with increased resistance of pathogenic fungi to the agents used in the therapeutic regimen and the limited number of drugs to cure these infections. As a result, the search for new drugs with antifungal activity has become increasingly important. The aim of this study is to study the antifungal activity of citronellal alone and in combination with amphotericin B or ketoconazole. The Minimal Inhibitory Concentration of citronellal, amphotericin B and ketoconazole against strains of Candida albicans were evaluated by the microdilution technique, and the Minimum Fungicide Concentration of citronellal against the same strains was also performed. Through the checkerboard methodology the effect of the combination of citronelal with amphotericin B or with ketoconazole was determined. This study showed that the association of citronellal with ketoconazole was shown to be an additive against one of the strains of C. albicans and indifferent to another strain. While the combined activity of citronellal and amphotericin B demonstrated an indifferent effect on the strains tested.

In vitro susceptibility of dermatophytes to oral antifungal drugs and amphotericin B in Uttar Pradesh, India.

Dermatophytosis is a major public health problem in our country. Although resistance to conventional oral and topical antifungal agents is being increasingly encountered, the sensitivity pattern of dermatophytes has not been systematically analysed. We aimed to determine the sensitivity pattern of dermatophyte isolates to amphotericin B and six oral antifungal drugs. Patients with dermatophytosis attending the outpatient department of dermatology were enrolled in the study. Samples were collected for mycological examination and in vitro antifungal sensitivity testing was done by broth microdilution as per the Clinical and Laboratory Standard Institute M38-A standards. A total of 804 patients were enrolled. Specimens from 185 patients (23%) were both KOH and culture positive, and 44 of these isolates (41 Trichophyton mentagrophytes and 3 Trichophyton rubrum) were subjected to sensitivity testing. Minimum inhibitory concentrations (MIC) of itraconazole, ketoconazole, voriconazole and amphotericin B were comparable. The median MIC to fluconazole was higher than the other tested drugs. Dermatophytes were most susceptible to ketoconazole and voriconazole, followed by itraconazole, amphotericin B, fluconazole and griseofulvin. A high incidence of resistance was found to terbinafine and the difference was statistically significant in comparison to fluconazole, itraconazole, voriconazole, ketoconazole (P = 0.001) and griseofulvin (P = 0.003). The strains were more sensitive to amphotericin B as compared to griseofulvin (P = 0.02) and terbinafine (P < 0.001). This was a hospital-based study and may not reflect the true pattern in the community. Only a few of the isolates were selected for study. The clinical response of patients, whose isolates were studied for in vitro sensitivity of the antifungals, was not studied. The sensitivity pattern of dermatophytes to various antifungals including amphotericin B, ketoconazole, voriconazole and itraconazole were determined. The studied isolates were least susceptible to terbinafine.

Genotyping of Candida albicans isolated from animals using 25S ribosomal DNA and ALT repeats polymorphism in repetitive sequence.

Background and Purpose: Candida albicans is the most prevalent Candida species isolated from animals. Candidiasis can be systemic in animals or may affect a single organ, such as the mouth, urinary tract, and skin. The aim of the present study was to determine the genetic diversity of C. albicans isolated from different animals and investigate the presence of a relationship between host specificity and genetic typing of C. albicans.Materials and Methods:For the purpose of the study, DNA extraction was performed on 27 clinical isolates of C. albicans obtained from animals. Subsequently, they were subjected to 25S ribosomal DNA amplification and ALT repeats in repetitive sequences (RPSs). The minimum inhibitory concentrations of fluconazole, ketoconazole, clotrimazole, nystatin, amphotericin B, and caspofungin were determined using the microdilution method based on the Clinical and Laboratory Standards Institute M27-S4 standard.Results:Out of 27 C. albicans strains, 11, 6, 5, and 5 cases were recognized as genotypes A (40.8%), E (22.2%), B (18.5%), and C (18.5%), respectively, through amplification using AS-I, which revealed 17 different types of C. albicans. By combining the two typing methods, 27 C. albicans strains were finally divided into 22 genotypes.Conclusion: Different genotypes showed genetic diversity among the C. albicans strains isolated from animal sources. The results revealed no special genotype relationship according to the host, anatomical source of isolation, and antifungal susceptibility.

A Ketoconazole Susceptibility Test for Malassezia pachydermatis Using Modified Leeming⁻Notman Agar.

The aim of this study was to establish a ketoconazole susceptibility test for Malassezia pachydermatis using modified Leeming–Notman agar (mLNA). The susceptibilities of 33 M. pachydermatis isolates obtained by modified CLSI M27-A3 method were compared with the results by disk diffusion method, which used different concentrations of ketoconazole on 6 mm diameter paper disks. Results showed that 93.9% (31/33) of the minimum inhibitory concentration (MIC) values obtained from both methods were similar (consistent with two methods within 2 dilutions). M. pachydermatis BCRC 21676 and Candida parapsilosis ATCC 22019 were used to verify the results obtained from the disk diffusion and modified CLSI M27-A3 tests, and they were found to be consistent. Therefore, the current study concludes that this new novel test—using different concentrations of reagents on cartridge disks to detect MIC values against ketoconazole—can be a cost-effective, time-efficient, and less technically demanding alternative to existing methods.