Medicinal compounds, chemically and biologically characterised from extracts of Australian Callitris endlicheri and C.glaucophylla (Cupressaceae): used traditionally in Aboriginal and colonial pharmacopoeia

ETHNOPHARMACOLOGICAL SIGNIFICANCE

Callitrisendlicheri and C.glaucophylla were highly valued by Australian Aboriginal people for use in medicinal applications. Pine needles were prepared using modalities of either smoking or topical preparations, requiring either aqueous or lipophilic extraction into animal fat. Extracts treated various ailments consistent with pathogenic infection, or other topical or tracheal ailments not clearly elucidated in ethnopharmacological records.

AIM OF THE STUDY

Here we aim firstly to investigate antimicrobial activities of both smoke, essential oil and solvent extracts and secondly to chemically characterise significant volatile compounds potentially related to medicinal or antimicrobial activities.

MATERIALS AND METHODS

Essential oils were produced using traditional hydrodistillation of pine needles collected from Callitrisendlicheri and C.glaucophylla. From the same material, solvent extracts were produced separately, using acetone and methanol, and then smoke extracts were produced with separate methods described herein, using fresh needles. All extracts were screened for antimicrobial activity against a range of bacterial organisms and sporicidal activity against pathogenic fungi (Trichophytonmentagrophytes, T.interdigitalis and T.rubrum).

RESULTS

Essential oils produced only modest antibacterial activity and the Callitris endlicheri essential oil had moderate antifungal activity. Smoke extracts demonstrated considerable broad spectrum antimicrobial activity, but solvent extracts demonstrated more selective activity against Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and the yeast Candida albicans. Chemical character of essential oils was consistent with previous studies; however, solvent and smoke extracts from fresh needles produced high concentrations of potentially medicinal abietane diterpenes, specifically pisiferal, pisiferol and ferruginol; well known from Japanese species with demonstrated bioactivity.

CONCLUSION

The occurrence of these diterpenes and other phenolics, in conjunction with significant antimicrobial activities from the various extracts, is in alignment with the use of Australian Callitris species in Aboriginal medicinal practice.

Quantification of dermatophyte viability for evaluation of antifungal effect by quantitative PCR

Dermatophytosis is a common disease caused by dermatophyte fungi such as Trichophyton rubrum and Trichophyton mentagrophytes. A method of quantifying fungal viability in the lesions of dermatophytosis is indispensable for understanding the therapeutic process and outcome; however, no such method has yet been developed. The aim of this study was to develop a method for quantifying dermatophyte viability by quantitative polymerase chain reaction (qPCR). The internal transcribed spacer (ITS) and D1/D2 regions, including each of rRNA and rDNA, were chosen as the targets, and dermatophyte-specific primer pairs were designed corresponding to ITS and D1/D2 regions. The amounts of target RNA and DNA after heat or antifungal treatment were measured by qPCR and compared with colony-forming unit (CFU) counts. RNA and DNA could extract from dermatophytes by mechanical pulverization of conidia using a Multi-Beads Shocker cell disruptor. Our method was sufficiently sensitive to detect 10 copies by qPCR using both ITS and D1/D2 primer pairs. The most sensitive target was ITS-cDNA after heat or antifungal treatment, and essentially consistent with CFU counts. On the other hands, ITS-DNA and D1/D2-DNA were not decreased soon after heat or antifungal treatment, but those were decreased significantly and reflected the CFU counts after 48 h of antifungal treatment. We conclude that ITS-cDNA is useful mainly for quantifying dermatophyte viability at early responses, but ITS-DNA and D1/D2-DNA are also available for evaluation, which does not need an early response.

Infection of keratinocytes with Trichophytum rubrum induces epidermal growth factor-dependent RNase 7 and human beta-defensin-3 expression

Human keratinocytes are able to express various antimicrobial peptides (AMP) to protect the skin from exaggerated microbial colonization and infection. Recently, in vitro growth-inhibiting activity of the skin-derived AMP psoriasin, RNase 7 and human beta-defensin (hBD)-2 against dermatophytes such as Trichophyton (T.) rubrum have been reported. To evaluate whether keratinocytes are able to respond to T. rubrum infection by an induced expression of AMP we exposed primary keratinocytes to living conidia of T. rubrum. This led to conidia germination and mycelial growth which was paralleled by a strong gene induction of the skin-derived AMP RNase 7 and hBD-3. Gene expression of the AMP psoriasin (S100A7) and hBD-2 were only slightly induced. The T. rubrum-mediated RNase 7 gene induction was accompanied by increased secretion of RNase 7. Parallel treatment of the keratinocytes with T. rubrum and the cytokine combination IL-17A/IFN-γ resulted in synergistic induction of RNase 7 and hBD-3 expression. Since patients receiving therapy by inhibition of the epidermal growth factor receptor (EGFR) more often suffer from dermatophytoses we investigated whether EGFR may be involved in the T. rubrum-mediated RNase 7 and hBD-3 induction. Primary keratinocytes incubated with an EGFR blocking antibody as well as with the EGFR antagonist AG1478 showed a significantly diminished RNase 7 and hBD-3 induction upon exposure of the keratinocytes to T. rubrum indicating that EGFR is involved in the T. rubrum-mediated induction of RNase 7 and hBD-3. The growth of T. rubrum in vitro was inhibited by hBD-3 in a dose-dependent manner suggesting that hBD-3 may contribute to cutaneous innate defense against T. rubrum. Taken together our data indicate that keratinocytes are able to initiate a fast defense response towards T. rubrum by the increased expression of AMP active against T. rubrum. A dysregulation of AMP may contribute to chronic and recurring dermatophytoses.

Detection of synergistic combinations of Baccharis extracts with terbinafine against Trichophyton rubrum with high throughput screening synergy assay (HTSS) followed by 3D graphs. Behavior of some of their components

Forty four extracts from nine Baccharis spp. from the Caulopterae section were tested in combination with terbinafine against Trichophyton rubrum with the HTSS assay at six different ratios with the aim of detecting those mixtures that produced a ≥50% statistically significant enhancement of growth inhibition. Since an enhanced effect of a combination respective of its components, does not necessarily indicate synergism, three-dimensional (3D) dose-response surfaces were constructed for each selected pair of extract/antifungal drug with the aid of CombiTool software. Ten extracts showed synergistic or additive combinations which constitutes a 22% hit rate of the extracts submitted to evaluation. Four flavonoids and three ent-clerodanes were detected in the active Baccharis extracts with HPLC/UV/ESI-MS methodology, all of which were tested in combination with terbinafine. Results showed that ent-clerodanes but not flavonoids showed synergistic or additive effects. Among them, bacchotricuneatin A followed by bacrispine showed synergistic effects while hawtriwaic acid showed additive effects.

De novo production of metabolites by fungal co-culture of Trichophyton rubrum and Bionectria ochroleuca

The co-cultivation of fungi has recently been described as a promising strategy to induce the production of novel metabolites through possible gene activation. A large screening of fungal co-cultures in solid media has identified an unusual long-distance growth inhibition between Trichophyton rubrum and Bionectria ochroleuca. To study metabolite induction in this particular fungal interaction, differential LC-MS-based metabolomics was performed on pure strain cultures and on their co-cultures. The comparison of the resulting fingerprints highlighted five de novo induced compounds, which were purified using software-oriented semipreparative HPLC-MS. One metabolite was successfully identified as 4″-hydroxysulfoxy-2,2″-dimethylthielavin P (a substituted trimer of 3,5-dimethylorsellinic acid). The nonsulfated form, as well as three other related compounds, were found in the pure strain culture of B. ochroleuca.

Antimicrobial activity of southern African medicinal plants with dermatological relevance: From an ethnopharmacological screening approach, to combination studies and the isolation of a bioactive compound

ETHNOPHARMACOLOGICAL RELEVANCE

Ethnobotanical reports on more than 100 southern African medicinal plants with dermatological relevance have been highlighted, yet there is still limited scientific data to support claims for their antimicrobial effectiveness against skin pathogens. Guided by ethnobotanical data, this paper explores the antimicrobial efficacies of southern African medicinal plants used to treat skin ailments.

AIM OF THE STUDY

To investigate the antimicrobial properties of southern African medicinal plants against dermatologically relevant pathogens. The study also aimed at providing a scientific rationale for the traditional use of plant combinations to treat skin diseases and the isolation of the bio-active compound from the most active species, Aristea ecklonii (Iridaceae).

MATERIALS AND METHODS

Organic and aqueous extracts (132) were prepared from 47 plant species and screened for antimicrobial properties against dermatologically relevant pathogens using the micro-titre plate dilution method. Four different plant combinations were investigated for interactive properties and the sum of the fractional inhibitory concentration (ƩFIC) calculated. Isobolograms were used to further investigate the antimicrobial interactive properties of Pentanisia prunelloides combined with Elephantorrhiza elephantina at varied ratios. A bioactivity-guided fractionation process was adopted to fractionate the organic leaf extract of Aristea ecklonii.

RESULTS

Plants demonstrating notable broad-spectrum activities (MIC values ≤1.00mg/ml) against the tested pathogens included extracts from Aristea ecklonii, Chenopodium ambrosioides, Diospyros mespiliformis, Elephantorrhiza elephantina, Eucalyptus camaldulensis, Gunnera perpensa, Harpephyllum caffrum, Hypericum perforatum, Melianthus comosus, Terminalia sericea and Warburgia salutaris. The organic extract of Elephantorrhiza elephantina, a plant reportedly used to treat acne vulgaris, demonstrated noteworthy antimicrobial activity (MIC value of 0.05mg/ml) against Propionibacterium acnes. Similarly, Diospyros mespiliformis reported for its traditional use to treat ringworm, also displayed noteworthy antimicrobial activity against Trichophyton mentagrophytes (MIC 0.10mg/ml) and Microsporum canis (MIC 0.50mg/ml). The aqueous root extracts of Pentanisia prunelloides combined (1:1) with Elephantorrhiza elephantina displayed synergistic interactions (ƩFIC values 0.31-0.38) against Staphylococcus aureus, gentamycin-methicillin resistant Staphylococcus aureus, Staphylococcus epidermidis and Candida albicans. Fractionation of Aristea ecklonii resulted in the isolation of the known bio-active compound, plumbagin, displaying noteworthy antimicrobial activity (MIC range between 2.00μg/ml and 16.00μg/ml).

CONCLUSION

Most of the plant extracts demonstrated pathogen specific antimicrobial effects with a few exhibiting broad-spectrum activities. Positive antimicrobial effects noted for plants such as Elephantorrhiza elephantina and Diospyros mespiliformis used for acne vulgaris and ringworm infections, respectively, give some validation to their reported traditiona l uses. Synergistic interactions noted for Pentanisia prunelloides combined with Elephantorrhiza elephantina validate an enhanced antimicrobial effect when used in combination. Noteworthy antimicrobial activities (MIC range between 2.00μg/ml and 16.00μg/ml) were observed for plumbagin isolated from Aristea ecklonii.

[Influence of the ecological group on the in vitro antifungal susceptibility of dermatophytic fungi]

BACKGROUND

Dermatophytes can be divided into geophilic (soil), zoophilic (animals) and anthropophilic (humans) strains, depending on the source of the keratin that they use for nutritional purposes.

AIMS

The in vitro susceptibility of clinical isolates of dermatophyte fungi has been studied in the 3 ecological groups with several antifungal agents for the topical management of dermatophytoses in order to determine their relationship with the ecological group.

METHODS

A standardised dilution micromethod in a liquid medium was used for the determination of the in vitro antifungal activity of 9 topical antifungal drugs: amorolfine (AMR), bifonazole (BFZ), clotrimazole, econazole, ketoconazole, miconazole, oxiconazole, terbinafine (TRB) and tioconazole. The in vitro activity was obtained against 124 clinical isolates of dermatophyte moulds from the anthropophilic, zoophilic and geophilic ecological groups.

RESULTS

The in vitro antifungal activity was different depending on the ecological group, although a species-dependent profile was also observed.

CONCLUSIONS

Azole derivatives showed a similar antifungal profile, being more active against anthropophilic dermatophytes > zoophilic > geophilic. Activity of TRB and AMR was different from that of azole derivatives (zoophilic > anthropophilic > geophilic). A higher in vitro antifungal activity against the 3 ecological groups was observed with TRB and AMR, whilst BFZ was the less active drug.

Effects of laser irradiation on Trichophyton rubrum growth and ultrastructure

BACKGROUND

Trichophyton rubrum (T. rubrum) is the most common causative agent of dermatophytosis worldwide. In this study, we examined the effect of laser irradiation on the growth and morphology of T. rubrum.

METHODS

Colonies of T. rubrum were isolated (one colony per plate), and randomly assigned to 5 treatment groups: Q-switched 694 nm ruby laser treatment, long-pulsed Nd:YAG 1064 nm laser treatment, intense pulsed light (IPL) treatment, 308 nm excimer laser treatment and the blank control group without treatment. Standardized photographs were obtained from grown-up fungal plates prior to treatment. Colonies were then exposed to various wavelengths and fluences of laser light. To compare the growth of colonies, they were re-photographed under identical conditions three and six days post-treatment. To investigate the morphology of T. rubrum, scanning electron microscope (SEM) and transmission electron microscope (TEM) images were obtained from specimens exposed to 24 hours of laser treatment.

RESULTS

Growth of T. rubrum colonies was significantly inhibited following irradiation by 694 nm Q-switched and 1064 nm long-pulsed Nd:YAG lasers. Other treatments exerted little or no effect. Q-switched laser irradiation exerted a stronger growth inhibitory effect than long-pulsed Nd:YAG laser irradiation. Following treatment by the Q-switched ruby laser system, T. rubrum hyphae became shrunken and deflated, and SEM images revealed rough, fractured hyphal surfaces, punctured with small destructive holes. TEM images showed that the hyphae were degenerating, as evidenced by the irregular shape of hyphae, rough and loose cell wall, and obscure cytoplasmic texture. Initially high electron density structure was visible in the cell; later, low-density structure appeared as a result of cytoplasmic dissolution. In contrast, the blank control group showed no obvious changes in morphology.

CONCLUSION

The Q-switched 694 nm ruby laser treatment significantly inhibits the growth and changes the morphology of T. rubrum.

Trichophyton Schoenleinii-induced widespread tinea corporis mimicking parapsoriasis

We report a case of extensive tinea corporis in an 80-year-old woman on her forearms, thighs, legs, buttocks and trunk, mimicking parapsoriasis due to Trichophyton schoenleinii, without scalp involvement. Diagnosis of Trichophyton schoenleinii was confirmed by microscopy and mycological culture specimens.

In vitro antifungal, anti-elastase and anti-keratinase activity of essential oils of Cinnamomum-, Syzygium- and Cymbopogon-species against Aspergillus fumigatus and Trichophyton rubrum

This study was aimed to evaluate effects of certain essential oils namely Cinnamomum verum, Syzygium aromaticum, Cymbopogon citratus, Cymbopogon martini and their major components cinnamaldehyde, eugenol, citral and geraniol respectively, on growth, hyphal ultrastructure and virulence factors of Aspergillus fumigatus and Trichophyton rubrum. The antifungal activity of essential oils and their major constituents was in the order of cinnamaldehyde>eugenol>geraniol=C. verum>citral>S. aromaticum>C. citratus>C. martini, both in liquid and solid media against T. rubrum and A. fumigatus. Based on promising antifungal activity of eugenol and cinnamaldehyde, these oils were further tested for their inhibitory activity against ungerminated and germinated conidia in test fungi. Cinnamaldehyde was found to be more active than eugenol. To assess the possible mode of action of cinnamaldehyde, electron microscopic studies were conducted. The observations revealed multiple sites of action of cinnamaldehyde mainly on cell membranes and endomembranous structures of the fungal cell. Further, test oils were also tested for their anti-virulence activity. More than 70% reduction in elastase activity was recorded in A. fumigatus by the oils of C. verum, C. martini, eugenol, cinnamaldehyde and geraniol. Similar reduction in keratinase activity in A. niger was recorded for the oils of C. martini and geraniol. Maximum reduction (96.56%) in elastase activity was produced by cinnamaldehyde whereas; geraniol caused maximum inhibition (97.31%) of keratinase activity. Our findings highlight anti-elastase and anti-keratinase activity of above mentioned essential oils as a novel property to be exploited in controlling invasive and superficial mycoses.

Antifungal activity of Aegle marmelos (L.) Correa (Rutaceae) leaf extract on dermatophytes

OBJECTIVE

To evaluate the in vitro antifungal activity of Aegle marmelos leaf extracts and fractions on the clinical isolates of dermatophytic fungi like Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum.

METHODS

The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of various extracts and fractions of the leaves of Aegle marmelos were measured using method of National Committee for Clinical Laboratory Standards (NCCLS).

RESULTS

Aegle marmelos leaf extracts and fractions were found to have fungicidal activity against various clinical isolates of dermatophytic fungi. The MIC and MFC was found to be high in water and ethyl alcohol extracts and methanol fractions (200µg/mL) against dermatophytic fungi studied.

CONCLUSIONS

Aegle marmelos leaf extracts significantly inhibites the growth of all dermatophytic fungi studied. If this activity is confirmed by in vivo studies and if the compound is isolated and identified, it could be a remedy for dermatophytosis.

Inhibition of growth of Trichophyton tonsurans by Lactobacillus reuteri

AIM

The aims of this study were to identify antifungal lactic acid bacteria (LAB) and characterize their activity against the dermatophyte Trichophyton tonsurans.

METHODS AND RESULTS

A total of 165 different LAB were isolated and initially screened for anti-Penicillium expansum activity. Five strains, which exhibited strong inhibitory activity, were then tested against the dermatophyte T. tonsurans DSM12285, where they also caused inhibition as observed by large fungal clearing on agar surface. The strongest inhibition was seen with Lactobacillus reuteri R2. When freeze-dried cell-free supernatant powder from this strain was incorporated in culture medium at concentrations >1%, growth of fungal colony was inhibited. Conidia germination was also inhibited under these conditions as determined by microscopy. The anti-T. tonsurans activity of Lact. reuteri R2 was not affected neither by heat treatment nor by proteolytic treatment using pronase E and proteinase K, indicating that the responsible agent(s) were nonproteinaceous in nature.

CONCLUSIONS

Lactobacillus reuteri R2 was identified as having strong inhibitory activity against the dermatophyte T. tonsurans DSMZ12285.

SIGNIFICANCE AND IMPACT OF THE STUDY

LAB are naturally associated with many foods and are well recognized for their biopreservative properties. The use of these and/or their products may well provide alternative safe approaches for the inhibition of dermatophytic fungi.

Synthesis, antimycobacterial, antifungal and photosynthesis-inhibiting activity of chlorinated N-phenylpyrazine-2-carboxamides

A series of sixteen pyrazinamide analogues with the -CONH- linker connecting the pyrazine and benzene rings was synthesized by the condensation of chlorides of substituted pyrazinecarboxylic acids with ring-substituted (chlorine) anilines. The prepared compounds were characterized and evaluated for their antimycobacterial and antifungal activity, and for their ability to inhibit photosynthetic electron transport (PET). 6-Chloro-N-(4-chlorophenyl)pyrazine-2-carboxamide manifested the highest activity against Mycobacterium tuberculosis strain H37Rv (65% inhibition at 6.25 μg/mL). The highest antifungal effect against Trichophyton mentagrophytes, the most susceptible fungal strain tested, was found for 6-chloro-5-tert-butyl-N-(3,4-dichlorophenyl)pyrazine-2-carboxamide (MIC = 62.5 μmol/L). 6-Chloro-5-tert-butyl-N-(4-chlorophenyl)pyrazine-2-carboxamide showed the highest PET inhibition in spinach chloroplasts (Spinacia oleracea L.) chloroplasts (IC₅₀ = 43.0 μmol/L). For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds as well as their structure–activity relationships are discussed.

Antifungal activity of essential oil from fruits of Indian Cuminum cyminum

The essential oil of fruits of Cuminum cyminum L. (Apiaceae), from India, was analyzed by GC and GC-MS, and its antifungal activity was tested on dermatophytes and phytopathogens, fungi, yeasts and some new Aspergilli. The most abundant components were cumin aldehyde, pinenes, and p-cymene, and a fraction of oxygenate compounds such as alcohol and epoxides. Because of the large amount of the highly volatile components in the cumin extract, we used a modified recent technique to evaluate the antifungal activity only of the volatile parts at doses from 5 to 20 microL of pure essential oil. Antifungal testing showed that Cuminum cyminum is active in general on all fungi but in particular on the dermatophytes, where Trichophyton rubrum was the most inhibited fungus also at the lowest dose of 5 microL. Less sensitive to treatment were the phytopathogens.

Substrate adaptation of Trichophyton rubrum secreted endoproteases

Trichophyton rubrum is the most common pathogen caused the dermatophytosis of nail and skin in human. The secreted proteases were considered to be the most important virulence factors. However, the substrates adaptation of T. rubrum secreted proteases is largely unknown. For the first time, we use the keratins from human nail and skin stratum corneum as the growth medium to investigate the different expression patterns of T. rubrum secreted endoproteases genes. During grow in both keratin-containing media SUB7 and MEP2 were the highest expressed gene in each family. These results indicated that SUB7 and MEP2 may be the dominant endoproteases secreted by T. rubrum during host infection and the other proteases may play a supplementary role. The direct comparison of T. rubrum grown on skin and nail medium showed different substrate favorite of secreted endoproteases. The genes MEP2, SUB5, SUB2 and SUB3 were more active during growth in skin medium, possibly these proteases have a higher affinity for skin original keratins. While the structures of SUB1, SUB4, and MEP4 maybe more suitable for the degradation of nail original keratins. This work presents useful molecular details for further understanding the pathogenesis of secreted proteases and the wide adaptation of T. rubrum.

[Antagonistic activity of bacteria from Bacillus genus against dermatophyte fungi]

Antagonistic properties of the strain Bacillus subtilis IB-54 with respect to dermatophyte fungi Trichophyton rubrum, T. mentagrophytes var. gypseum, Microsporum canis was studied. The studied strains of bacilli effectively inhibited growth and development of dermatophytes when were cultivated on the media containing different carbon sources. Experiments on laboratory animals showed that B. subtilis IB-54 displayed no virulence, toxicity, and toxigenicity and can be considered as perspective object for development of antimycotic drugs.

Widespread tinea corporis caused by Trichophyton rubrum with non-typical cultural characteristics--diagnosis via PCR

From the epidemiological point of view, Trichophyton rubrum is the most important dermatophyte in the Western world. Mostly, the lesions of fungal infections of the skin are restricted and circumscribed. Immunodeficiency, diabetes or treatment with steroids, however, favour widespread disease involving the entire integument. In the present study, we describe a patient without immunodeficiency or diabetes presenting with widespread tinea corporis caused by T. rubrum. The fungal isolate showed atypical morphological features. Moreover, the typical metabolic features (negative urease test, production of red pigment on potato dextrose agar) were expressed with delay after 6 weeks of cultivation. Thus, sequencing of the internal transcribed spacer of the ribosomal DNA was applied to identify the fungal isolate and led us to the correct diagnosis, before conventional mycological methods were successful.

cDNA representational difference analysis used in the identification of genes expressed by Trichophyton rubrum during contact with keratin

Dermatophytes are adapted to infect skin, hair and nails by their ability to utilize keratin as a nutrient source. Trichophyton rubrum is an anthropophilic fungus, causing up to 90% of chronic cases of dermatophytosis. The understanding of the complex interactions between the fungus and its host should include the identification of genes expressed during infection. To identify the genes involved in the infection process, representational difference analysis (RDA) was applied to two cDNA populations from T. rubrum, one transcribed from the RNA of fungus cultured in the presence of keratin and the other from RNA generated during fungal growth in minimal medium. The analysis identified differentially expressed transcripts. Genes related to signal transduction, membrane protein, oxidative stress response, and some putative virulence factors were up-regulated during the contact of the fungus with keratin. The expression patterns of these genes were also verified by real-time PCR, in conidia of T. rubrum infecting primarily cultured human keratinocytes in vitro, revealing their potential role in the infective process. A better understanding of this interaction will contribute significantly to our knowledge of the process of dermatophyte infection.

The effect of dermatophytes on cytokine production by human keratinocytes

Dermatophytosis (tinea) is a common disease in superficial mycoses and is generally confined to the stratum corneum in the epidermis and cutaneous appendages. The mechanisms by which dermatophytes cause dermatophytosis, however, are poorly understood. In this study, we evaluated the effect of Trichophyton mentagrophytes, T. tonsurans and T. rubrum on cytokine production by normal human epidermal keratinocytes (NHEKs). After 3-24 h of co-culture of NHEKs with each of the dermatophytes, cytokines in the supernatant were measured by enzyme-linked immunosorbent assay. Promoter activity of IL-8 was measured by chloramphenicol acetyl transferase (CAT) assay. IL-8 and GRO-alpha levels were higher in supernatants co-cultured with T. mentagrophytes isolates from animal than in those with T. mentagrophytes isolates from human, and with T. tonsurans and T. rubrum isolates. CAT expression for IL-8 promoter activity was higher in cell lysates stimulated with T. mentagrophytes isolates from animal than in those with T. mentagrophytes isolates from human, and with T. tonsurans and T. rubrum isolates. These findings suggest that dermatophytes directly induce production of cytokines at the transcriptional level by human keratinocytes, and that there are differences in their ability to induce cytokine production between the dermatophytes.

Antibacterial and antifungal activity of Cassia fistula L.: an ethnomedicinal plant

Hexane, chloroform, ethyl acetate, methanol and water extracts from the flower of Cassia fistula (an ethnomedicinal plant) were tested against bacteria and fungi. All the extracts exhibited antibacterial activity against Gram-positive organisms with minimum inhibitory concentrations (MIC) between 0.078 and 2.5 mg/ml. Among the Gram-negative bacteria, only Pseudomonas aeruginosa was susceptible to the extracts. Ethyl acetate crude extract was fractionated using chromatographic techniques. A crystal was isolated, which was confirmed as 4-hydroxy benzoic acid hydrate using X-ray crystallography. It exhibited antifungal activity against Trichophyton mentagrophytes (MIC 0.5 mg/ml) and Epidermophyton floccosum (MIC 0.5 mg/ml).

Isolation of transcripts over-expressed in human pathogen Trichophyton rubrum during growth in keratin

Trichophyton rubrum is a cosmopolitan and anthropophilic fungus able to invade keratinized tissue, causing infection in human skin and nails. This work evaluated the changes in the extracellular pH during its growth in keratin (after 6, 12, 24, 48, 72h and 7 days) at initial pH 5.0. We observed a gradual increase of basal pH under keratin exposure when compared to glucose condition. Also, we identified 576T. rubrum transcripts differentially expressed by subtractive suppression hybridization (SSH) using conidia cultivated for 72h in keratin as tester, and cultivated in glucose as driver. The over-expression of 238 transcripts obtained under keratin condition was confirmed by macro-array dot-blot, revealing 28 unigenes. Putative proteins encoded by these genes showed similarity to fungi proteins involved in basic metabolism, growth and virulence, i.e., transporters ABC-MDR, MFS and ATPase of copper, NIMA interactive protein, Gag-Pol polyprotein, virulence factors serine-protease subtilisin and metalloprotease, cytochrome P450, GlcN-6-phosphate deaminase and Hsp30. The upregulation of T. rubrum genes encoding subtilisin, metalloprotease and Gag-Pol polyprotein was also validated by northern blot. The results of this study provide the first insight into genes differentially expressed during T. rubrum grown in keratin that may be involved in fungal pathogenesis.

Deep dermatophytosis caused by Trichophyton rubrum: report of two cases

Two patients presenting with subcutaneous nodules, plaques, papules and ulceration caused by Trichophyton rubrum are described in this report. The first case was a 46-year-old woman referred with erythema and desquamation over her trunk, hands and feet for 30 years, progressing to nodules and ulceration over her trunk, arms and scalp for the last 2 years. The second case was a 34-year-old man who presented with a 2-year-history of itchy, erythema and desquamation over the trunk, progressing to papules, nodules and cyst around his ear, on the neck and scalp for 1 year. The diagnoses were suspected after direct microscopical examinations of the discharge materials, which revealed the presence of hyaline hyphae. The histological examinations showed granulomatous inflammatory infiltrates with fungal elements in the dermis including epithelioid cells, giant cells, lymphocytes and eosinophils, and the periodic acid-Schiff stain showed hypha within the granulomas. Cultures of puncture materials, skin biopsies and nails confirmed the diagnosis identifying T. rubrum. Antifungal therapies with itraconazole were successful in both patients, the lesions were completely clear with atrophic scars after 3 months. Side effects were not noticed during the medication. We discuss the clinical types of granulomatous cutaneous lesions caused by dermatophyte infections and evaluate the therapeutic effect of itraconazole.

Antifungal susceptibility testing of Trichophyton rubrum by E-test

Trichophyton rubrum isolates were used in susceptibility testing for azoles by E-test. Voriconazole was the most and fluconazole was the less-active drug. Our results are in agreement with susceptibility data observed by researchers that used others' methodologies. E-test seems to be a reliable methodology to susceptibility-testing for T. rubrum.