Screening of alkaloids and withanolides isolated from Solanaceae plants for antifungal properties against non-wild type Sporothrix brasiliensis

Antifungal resistance has often been found in animal sporotrichosis in Southern Brazil. The biological potential of compounds from plants of the Solanaceae family against infectious diseases is known, however, it is still unknown against Sporothrix brasiliensis. This study evaluated the anti-Sporothrix brasiliensis activity, synergism, cytotoxicity, and action mechanism of steroidal lactones (withanolides) and alkaloids isolated from these plants. Pure compounds of withanolide D (WNOD), physalin F (PHYF), withanicandin (WNIC), nicandin B (NICB), solasonine (SSON), and solamargine (SMAR) were tested against 12 Sporothrix brasiliensis isolated from cats (n = 11) and dogs (n = 2) through M38-A2 CLSI. For the compounds with the best activity, a checkerboard assay for synergism, sorbitol protection, and ergosterol effect for action mechanism; and MTT test for cytotoxicity were performed. The withanolides WNOD, PHYF, WNIC, and NICB were not antifungal, but SSON (MIC 0.125-1 mg/mL) and SMAR (MIC 0.5-1 mg/mL) were both fungistatic and fungicidal (MFC 0.5-1 mg/mL for both) against wild-type (WT) and non-WT isolates. The activity of SSON and SMAR was indifferent when combined with itraconazole. In the mechanism of action, cell wall and plasma membrane by complexation with ergosterol seemed to be two target structures of SSON and SMAR. SSON was selected for cytotoxicity, whose cell viability in MDBK cells ranged from 28.85 % to 101.75 %, and was higher than 87.49 % at concentrations ≤0.0015 mg/ml. Only the steroidal alkaloids SSON and SMAR were active against non-WT isolates, being promising antifungal candidates for the treatment of feline and canine sporotrichosis with low susceptibility to itraconazole.

An evaluation of techniques to diagnose Dioctophyme renale in dogs

Dioctophyme renale is a nematode with zoonotic potential that affects the kidneys of carnivorous, wild, and domestic mammals. In this study, we sought to evaluate the indirect ELISA method against routine methods used to diagnose dioctophimosis. Hence, 38 dogs parasitized by D. renale, as confirmed by surgery, were selected. The dogs were evaluated by abdominal ultrasound and urinalysis, and their sera were tested by indirect ELISA using D. renale adult secretion and excretion antigen (DES). Five dogs were followed up with serum collections on day 0 (day of surgery) and 30, 60, and 90 days after surgery to evaluate antibody kinetics. Abdominal ultrasound and indirect ELISA successfully diagnosed 37 dogs parasitized by D. renale, while urinalysis diagnosed 29 animals. The positive animals were parasitized with 1-7 parasites; 17 dogs were infected by male and female parasites, 15 only by female parasites, and six were parasitized only by male parasites. When assessing specificity and sensitivity, all techniques showed 100% specificity and 81.6%, 97.4%, and 97.4% sensitivity for urinalysis, ultrasound, and ELISA, respectively (p < 0.001). The five positive dogs that were followed up after surgery showed a progressive decrease in mean absorbances in indirect ELISA (0.644, 0.516, 0.511, and 0.440, respectively). This study demonstrated that the indirect ELISA using the DE antigen could diagnose dioctophimosis regardless of the number, sex, and location of the parasites, with the potential to be used in epidemiological research and implementing immunological and molecular studies, opening new lines of research on D. renale.

Nephrectomy in 52 dogs for the treatment of Dioctophyme renale infection - Knowing the enemy to win

Dioctophyme renale (D. renale) is a nematode that parasitizes the kidney of mammals. Treatment is often surgical, with removal of the affected organ. This retrospective study aims to evaluate the epidemiological, clinical, and surgical aspects, the interval between diagnosis and treatment, the occurrence of pre- and intraoperative complications, and the postoperative survival time of dogs parasitized by D. renale undergoing therapeutic nephrectomy. Records of fifty-two dogs treated in a single hospital service were analyzed. We collected epidemiological data, laboratory results, diagnostic method, anesthetic protocol, surgical technique and time, type of antimicrobial prophylaxis, pre- and intraoperative complications, location and number of parasites, and postoperative survival time. Of the 52 dogs undergoing right nephrectomy by laparotomy, 61.5 % were female and 63.4 % were adults. Although the most common clinical sign was hematuria (25 %), 61.5 % of the patients were asymptomatic. Eosinophilia and increased serum urea were the only laboratory changes found. The interval between diagnosis and surgery was 27.4 ± 23 days and no patient showed changes suggestive of surgical emergency. The most common surgical approach was the right paracostal (61.5 %), and a continuous suture pattern was predominant. Intraoperative complications occurred in 9.6 % of the procedures, varying from mild to severe hemorrhage. Mean postoperative survival was 835.5 ± 428 days. Dioctophymosis was effectively controlled by nephrectomy of the affected kidney, allowing a mean survival of more than 830 days. No serious complications caused by intervals between diagnosis and treatment have been reported. This is the largest retrospective study evaluating dogs infected with D. renale that were surgically treated.

Are polar extracts and essential oil from Origanum vulgare Linn. (oregano) an alternative against itraconazole-resistant dermatophytes from veterinary cases?

Although the conventional therapy against dermatophytosis is based on antifungal drugs and environmental disinfection, the emergence of itraconazole(ITZ)-resistant dermatophytes has encouraged the search for active compounds, such as Origanum vulgare L. (oregano) essential oil (EO). However, little is known about its effect in polar extracts or the mechanism of action of these extracts and EO. We investigated the antifungal activity of four polar extracts and one EO from oregano against ITZ-susceptible and ITZ-resistant dermatophytes and their action mechanism. Polar extracts were prepared as infusions at 10 (INF10) and 60 (INF60) minutes, decoction (DEC) and hydroalcoholic extract (HAE); EO was purchased. All extracts and itraconazole were tested against Microsporum gypseum, M. canis, M. nanum, Trichophyton mentagrophytes and T. verrucosum isolated from cats, dogs and cattle (n = 28), and humans (n = 2) (M38-A2, CLSI). Among polar extract, DEC stood out as antifungal, followed by INF10 and INF60; HAE was little active. For EO, all isolates were susceptible, including ITZ-resistant dermatophytes. EO was selected for action mechanism assays, and acted in cell wall and plasmatic membrane by complexing with fungal ergosterol. By chromatographic analysis, 4-hydroxibenzoic acid was the most prevalent compound in all polar extracts, followed by syringic acid and caffeic acid; luteolin was present only in HAE. For EO, carvacrol was the major compound (73.9%); followed by γ-terpinene (3.6%) and thymol (3.0%). These findings showed that the extract type of oregano has influenced the antifungal action on dermatophytes, highlight EO and DEC, that are promising as antifungal agent, including against ITZ-resistant dermatophytes.

Are γ-terpinene, 1,8-cineole, p-coumaric acid, and quercetin active against wild-type and non-wild-type Sporothrix brasiliensis to itraconazole?

The emergence of itraconazole (ITZ)-resistant Sporothrix brasiliensis in feline and canine cases in southern Brazil has hampered the clinical cure of animal sporotrichosis, encouraging the search for therapeutic alternatives. The promising use of plants extracts from Lamiaceae family is known; however, there are no studies with its major compounds, as γ-terpinene (γTER), 1,8-cineole (1,8CIN), p-coumaric acid (pCOU), and quercetin (QUER). For the first time, we evaluated the antifungal, synergistic, cytotoxic activities and action mechanism of these compounds against S. brasiliensis. For this, 28 S. brasiliensis from cats (n = 24) and dogs (n = 4) and standard strains of S. brasiliensis and S. schenckii (n = 4) were tested by M38-A2 (CLSI), revealing non-wild-type (WT) isolates to ITZ on 54.2% (13/24) and 75% (03/04) of feline and canine isolates, respectively. Of the compounds, γTER stood out against all isolates (MIC/MFC 0.75 to > 3 mg/ml; MIC50 3 mg/ml). However, 1,8CIN, pCOU, and QUER showed little or no activity (MIC50 > 3 mg/ml). Thus, γTER was selected for checkerboard assay, whose combination with ITZ showed synergistic (WT isolates) and indifferent (non-WT isolates) interaction. For action mechanism (sorbitol protection and ergosterol effect), γTER acted in membrane by complexing with fungal ergosterol and at the cell wall level, showing two possible pathways as antifungal target. Finally, cytotoxicity (MTT assay) showed that γTER was the safest compound on MDBK cells, even at a concentration of 3 mg/ml (90.16%). Our findings support that γTER is a potent antifungal candidate for the control of sporotrichosis, including against non-WT S. brasiliensis.

Ovicidal activity of the hydroalcoholic extract of Brazilian peppertree (Schinus terebinthifolia Raddi) against Ancylostoma spp. from naturally parasitized dogs

This study aimed to evaluate the ovicidal activity of the hydroalcoholic extract of Schinus terebinthifolia (SCH; T1) against Ancylostoma spp. and its influence of storage time in the extract stored for 36 months (T36). Eggs of Ancylostoma spp. were obtained from naturally parasitized dogs, and used for the larval hatchability test, where the eggs were exposed to T1 and T36 extracts of SCH (15-0.625 mg/mL). In T1, all concentrations inhibited more than 80% of the eggs, being 100% at concentrations between 15 and 5 mg/mL (p > 0.05). At T36, all concentrations were active, even the ones between 2.5 and 0.625 mg/mL, with 100% inhibition (p < 0.05), revealing that the storage time maintained the ovicidal action. By LC-MS, T36 presented ethyl gallate, myricitrin, and gallic acid as major compounds. These findings support the promising use of SCH extract as an ovicide against Ancylostoma spp., even stored for 36 months of shelf life.

Bioisosteric modification on benzylidene-carbonyl compounds improved the drug-likeness and maintained the antifungal activity against Sporothrix brasiliensis

Considering the emergence of antifungal resistance on Sporothrix brasiliensis, we aimed to assess new benzylidene-carbonyl compounds against feline-borne S. brasiliensis isolates. The compounds were designed as bioisosteres from previously reported benzylidene-ketones generating the p-coumaric (1), cinnamic (2), p-methoxycinnamic (3) and caffeic acid (4) analogues. The corresponding compounds were tested against feline isolates of S. brasiliensis with sensitivity (n = 4) and resistance (n = 5) to itraconazole (ITZ), following the M38-A2 protocol (CLSI, Reference method for broth dilution antifungal susceptibility testing of filamentous fungi M38-A2 Guideline, 2008). Eleven analogues showed activity against all fungal strains with minimum inhibitory concentrations (MIC) ≤1 mg/ml (1a-d, 2e, 3b, 3e, 4, 4a and 5e) and fungicidal concentrations (MFC) ≤1 mg/ml (1b, 1d, 3e and 4a), whereas 3 was the less active with both MIC and MFC values above 1 mg/ml. Compound 3e (4-methoxy-N-butylcinnamamide) was the most potent (MIC_range 0.08-0.16 mg/ml; MFC_range 0.32-0.64 mg/ml) from the set, suggesting a different role of the substituents in ester and amide derivatives. The designed compounds proved to be important prototypes with improved drug-likeness to achieve compounds with higher activity against ITZ-resistant S. brasiliensis.

Can the essential oil of rosemary (Rosmarinus officinalis Linn.) protect rats infected with itraconazole-resistant Sporothrix brasiliensis from fungal spread?

INTRODUCTION

Itraconazole is the first-choice option to treat human and animal sporotrichosis. However, the emergence of itraconazole-resistant strains has encouraged research on new active antifungals. Among them, the essential oil of rosemary (Rosmarinus officinalis Linn., Lamiaceae) has shown antifungal activity in vitro.

OBJECTIVE

Assessing, for the first time, the effectiveness of rosemary essential oil in vivo in experimental cutaneous sporotrichosis, as well as its chemical composition and action mode.

METHODS

Itraconazole-resistant Sporothrix brasiliensis was inoculated in the left foot pad of 30 Wistar rats, which were randomized (n=10) for treatment with saline solution (control, CONT), itraconazole (ITRA, 10 mg/kg) and rosemary oil (ROSM, 250 mg/kg) for 30 days at an oral dose of 1 mL, daily. Clinical evolution, histopathology and fungal burden were investigated. GC-MS was used for chemical analysis; sorbitol protection and ergosterol effect were used to evaluate the action mechanism of rosemary oil.

RESULTS

ROSM was the only group evolving to skin lesion remission, lack of edema and exudate, and mild-to-absent yeast cells. Rosemary oil delayed fungal spreading and protected systemic organs, mainly liver and spleen. The ROSM group presented lower fungal load than that observed for the CONT and ITRA groups (p<0.05). Antifungal action took place at complexation level after ergosterol application. Most compounds were 1,8-cineole/eucalyptol (47.91%), camphor (17.92%), and α-pinene (11.52%).

CONCLUSIONS

These findings have evidenced that rosemary oil is a promising antifungal to treat sporotrichosis, since it protects systemic organs from fungal spread.

Chemical, antioxidant and cytotoxic profile of hydroalcoholic extracts of plants from Southern Brazil and their activity against pathogenic fungi isolated from dogs and cats with sensitivity and resistance to conventional antifungals

We aimed to evaluate the chemical, antioxidant, cytotoxic, and antifungal activities of hydroalcoholic extracts of native plants from Southern Brazil: Schinus terebinthifolia (SCH), Persicaria hydropiperoides (PER), Eugenia uniflora (EUG) and Equisetum hyemale (EQU). Ethyl gallate, quercetin, and quinic acid were prevalent compounds identified by LC-MS. For total phenolic/flavonoid contents and the antioxidant potential against ABTS/DPPH radicals, the ascending order was EQU < PER < EUG < SCH. All extracts were low cytotoxic and kept a high Vero cell viability (>75%) at concentrations up to 12.5 mg/mL (MTT assay). By M38-A2/M27-A3 (CLSI) against 68 clinical isolates of animals and strains of Malassezia pachydermatis, Sporothrix brasiliensis, Microsporum canis, Microsporum gypseum and Trichophyton mentagrophytes, all extracts (MIC/MFC ≤3.13-100 mg/mL) were active, except EUG. SCH inhibited and killed S. brasiliensis (MIC/MFC_50/90 3.12-12.5 mg/mL) and dermatophytes (MIC/MFC 6.25-25 mg/mL) resistant to ketoconazole and itraconazole. These findings support the promising use of the selected plant extracts as antifungal agents.

Multiresistant bacteria isolated from domestic and wild animals with skin lesions were susceptible to native plants from Southern Brazil

We evaluated the chemical composition, toxicity, and antibacterial activity of Schinus terebinthifolia (SCH), Eugenia uniflora (EUG), Persicaria hydropiperoides (PER), Equisetum hyemale (EQU), Solidago chilensis (SOL), and Baccharis trimera (BRA). These plants were tested (7.5-0.01 mg/mL) against Gram-positive (G+; n = 32) and Gram-negative (G-; n = 26) isolates from animals (M07-A9, CLSI). Antibiogram (disk diffusion), chromatographic analysis (UPLC), and toxicity assay (HET-CAM) were also performed. A high incidence of resistance was noted, in which 18.4% (07/38) of G+ (Staphylococcus intermedius/Enterococcus faecium) and 17.7% (06/34) of G- (Pseudomonas aeruginosa/Escherichia coli/Proteus mirabilis) were multidrug-resistant. All bacteria were sensitive (MIC₅₀) to SCH (both 3.75 mg/mL), EUG (3.75 mg/mL and 7.5 mg/mL, respectively) and PER (both 7.5 mg/mL). SCH/EUG/PER highlighted as antibacterial, probably due to the major compounds (ethyl gallate, quinic acid, quercetin). These extracts showed normal embryonic development (SCH/EUG: 7.5-0.94 mg/mL). These findings highlighted the promising use of native plants for therapeutic purposes.

Dioctophimosis: A Parasitic Zoonosis of Public Health Importance

Dioctophyme renale, the giant kidney worm, is a renal nematode from domestic and wild mammals that has zoonotic potential. In humans, dioctophimosis has been reported in several countries, mainly on the Asian continent, totaling more than 40 cases, which describe the parasite mainly infecting the kidneys, bladder, urethra and skin. Infection in animals and humans is related to the ingestion of the infective larva (L3) present in the aquatic oligochaete annelid (mandatory intermediate host) or fish and anurans (facultative paratenic hosts). Thus, the infection is related to the habit of drinking water contaminated with the mandatory intermediate host, as well as raw or undercooked meat from the facultative paratenic hosts. Dioctophimosis destroys the renal parenchyma and, in some cases, can cause the death of its hosts. In this chapter, we discuss the main topics regarding dioctophimosis in humans, domestic and wild animals, highlighting its importance in public health.

Disseminated histoplasmosis in a cat rescued in Fortaleza, Brazil, and successfully treated with itraconazole - First case report identified molecularly

An unneutered female cat of unknown age presented bloody lesions on the edematous face, and respiratory signs. Cytology and culture from the skin sample collected with fine-needle aspiration showed yeasts inside activated macrophages, and fungal growth characteristic of Histoplasma spp., which was molecularly confirmed that was Histoplasma capsulatum var. capsulatum. The cat was successfully treated with oral itraconazole (10 mg/kg/daily) for 120 days. This is the first case report of feline histoplasmosis confirmed molecularly in Brazil.

Jabuticaba [Plinia peruviana (Poir.) Govaerts]: a Brazilian fruit with a promising application against itraconazole-susceptible and -resistant Sporothrix brasiliensis

Hydroalcoholic extract from Jabuticaba peels was evaluated for the chemical profile, antioxidant potential, cytotoxicity, and anti-Sporothrix brasiliensis activities against both dimorphic phases. Higher phenolic content (14.91 ± 0.97) compared to flavonoid (2.05 ± 1.00) associated with the ellagic acid (1.93 ± 0.03; LC-MS), and a good scavenging ability against ABST and DPPH radicals was noted. On MDBK cells, elevated cell viability (>90%) was demonstrated between 0.39 and 0.097 mg/ml (MTT assay). Mycelial (CLSI M38-A2) and yeast (CLSI M27-A3) phases of 18 isolates of Sporothrix brasiliensis from cats (n = 8), dogs (n = 8) and humans (n = 2) were used. They were identified itraconazole-susceptible and itraconazole-resistant isolates in both phases, which were all inhibited (MIC of ≤1.56-6.25 mg/ml for both phases) and killed (MFC of ≤1.56-12.5 mg/ml for mycelial; ≤1.56-50 mg/ml for yeast) by Jabuticaba. For the first time, these findings highlighted the potential usefulness of hydroalcoholic extract from Jabuticaba peel as a promising antifungal against sporotrichosis.

Benzylidene-carbonyl compounds are active against itraconazole-susceptible and itraconazole-resistant Sporothrix brasiliensis

We evaluated the antifungal activity of benzylidene-carbonyl compounds (LINS03) based on the structure of gibbilimbol from Piper malacophyllum Linn. Five analogues (1-5) were synthetized following a classic aldol condensation between an aromatic aldehyde and a ketone, under basic conditions. These were tested against itraconazole-susceptible (n = 3) and itraconazole-resistant (n = 5) isolates of Sporothrix brasiliensis by M38-A2 guidelines of CLSI. All of them were fungistatic (MIC ranged of 0.11-0.22 mg/mL (1); 0.08-0.17 mg/mL (2); 0.05-0.1 mg/mL (3); 0.04-0.33 mg/mL (4); and 0.04-0.3 mg/mL (5)), highlighting compounds 2 and 3. As fungicidal, compounds 1 and 2 were highlighted (MFC ranged of 0.22-0.89 mg/mL and 0.08-1.35 mg/mL, respectively), compared with the remaining (0.77-> 3.08 mg/mL (3); 0.08-> 2.6 mg/mL (4); and 0.59-> 2.37 mg/mL (5)). The inhibitory activity was related to the benzylidene-carbonyl, whereas the phenol group and the low chain homolog seems to contribute to some extent to the fungicidal effect. Compound 2 highlighted due to the considerable fungistatic and fungicidal activities, including itraconazole-resistant Sporothrix brasiliensis. These findings support the potential usefulness of benzylidene-carbonyl compounds as promising prototypes for the development of antifungal against sporotrichosis by Sporothrix brasiliensis, including against itraconazole-resistant isolates.

Susceptibility and resistance of Sporothrix brasiliensis to branded and compounded itraconazole formulations

Itraconazole is the first drug of choice for the treatment of sporotrichosis and it is available at different concentrations for veterinary patients. However, therapeutic failure has been reported, limiting clinical treatment. This study evaluated the in vitro efficacy of brand-name and compounded itraconazole formulations against Sporothrix brasiliensis and estimated the itraconazole content in each tested formulation. Oral capsules were acquired from two brand-name products for human (H-IND) and veterinary (V-IND) uses, and three from compounding pharmacies in Pelotas, RS, for human (H-COMP1/H-COMP2) and veterinary (V-COMP) uses. Capsule purity was analyzed by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). Antifungal activity was determined against 29 Sporothrix brasiliensis by the M38-A2 guideline of CLSI. H-IND/H-COMP1/H-COMP2 had high efficacy against S. brasiliensis (approximately 70% of total isolated susceptible), V-COMP showed moderate efficacy (51.7%), and V-IND was the least effective formulation (37.9%). Thirty-four percent of the total isolates were resistant to all formulations. Furthermore, itraconazole content did not match the concentration indicated by the manufacturers, ranging from 387.70 to 7.81 μg/mg (H-COMP2 > V-COMP > H-IND > H-COMP1 > V-IND). Therefore, it is possible that the formulations showed different in vitro efficacy due to the difference in their itraconazole contents. Given the emergence of antifungal resistance for all formulations, the choice product to be used must follow susceptibility testing. Stringent quality control measures are recommended for product manufactures to assure drug content uniformity.

Ovicidal and larvicidal potential of Rosmarinus officinalis to control gastrointestinal nematodes of sheep

Abstract Gastrointestinal Nematode Infection (GIN) are the main constraint to the production of small ruminants. Studies of medicinal plants have been an important alternative in the effort to control these parasites. Therefore, the purpose of this study was to evaluate the in vitro ovicidal and larvicidal activity of essential oil of Rosmarinus officinalis. The oil was extracted, analyzed by gas chromatography and tested on GIN eggs and larvae in six concentrations, 227.5mg/mL, 113.7mg/mL, 56.8mg/mL, 28.4mg/mL, 14.2mg/mL and 7.1mg/mL. To determine the ovicidal activity, GIN eggs were recovered from sheep feces and incubated for 48h with different concentrations of the oil. For the evaluation of larval migration, third-stage larvae (L3) were obtained by fecal culture, and associated with the essential oil for 24h at the same concentrations, after which they were left for another 24 hours on microsieves, followed by the count of migrating and non-migrating larvae. The assays of R. officinalis oil showed a significant (p<0.05) 97.4% to 100% inhibition of egg hatching and a significant (p<0.05) 20% to 74% inhibition of larval migration. The main constituent revealed by gas chromatography was Eucalyptol. The results indicate that R. officinalis essential oil has ovicidal and larvicidal activity on sheep GINs.

Polar Origanum vulgare (Lamiaceae) extracts with antifungal potential against Sporothrix brasiliensis

Oregano (Origanum vulgare) has anti-Sporothrix spp. activity, including against strains that are resistant to antifungal drugs. As the studies are limited to the essential oil, the aim of this study was to evaluate the chemical, antioxidant and cytotoxic properties of polar oregano extracts and their anti-Sporothrix brasiliensis activity. Aerial plant parts were used in the preparation of 10 min (INF10) and 60 min (INF60) infusions, a decoction (DEC) and a hydroalcoholic extract (HAE). Six phenolic acids and four flavonoids were identified and quantified through liquid-chromatography (LC-MS). Extracts in increasing order of total phenolic and flavonoid contents were HAE<INF60<INF10<DEC and HAE<DEC<INF60<INF10, respectively. All extracts showed DPPH and ABTS radical scavenging potential (HAE<INF60<DEC<INF10). HAE showed the least toxicity toward MDCK and CRFK cell lines in the MTT colorimetric assay. The antifungal potential against 29 S. brasiliensis isolates obtained from cats and dogs was evaluated following the CLSI M38-A2 protocol adapted to natural products. Minimum inhibitory concentration for 50% of the isolates (MIC50) was 5 mg/ml for all extracts, and minimum fungicidal concentration for 50% of the isolates (MFC50) was 20 mg/ml for INF10 and 40 mg/ml for the remaining extracts. MIC90 was 10 mg/ml for all extracts, except for DEC (20 mg/ml). MFC90 was 40 mg/ml for INF10 and > 40 mg/ml for the other extracts. This is the first report of oregano extracts showing antifungal activity against S. brasiliensis. Its use in the treatment of sporotrichosis may be considered upon toxicity and safe-use conditions are tested.

Environmental contamination by parasitic forms in a socially vulnerable community in southern Rio Grande do Sul state: a serious public health problem

vulnerability. The fact that these people share the environment with animals promotes the establishment of zoonotic parasitic infections, as well as the resultant parasitic cycles. Thus, parasites present in the environment must be identified, so that control measures can be recommended. In this context, this study’s objective was to evaluate environmental contamination by parasitic forms in a socially vulnerable community in southern Rio Grande do Sul. A total of 100 soil samples collected from the community were processed by a sodium dichromate centrifuge-flotation technique and analyzed by a compound microscope (40X objective) for the identification of parasite eggs, oocysts and cysts. All points were positive for two or more parasites, with the identification of 33.59% non-identified coccidian oocysts, Strongylida (25.4%), Ascaridida (21.31%), Trichuris spp. (8.19%), Toxocara spp. (3.27%), Amoebas (4.08%), Dioctophyma renale (2.45%), and Giardia spp. (1.63%). The presence of parasitic forms in all points analyzed surpasses other studies of environmental contamination carried out in the southern region of Brazil. In addition, the identification of several parasitic forms with zoonotic potential is concerning, since it shows the possibility of parasitic transmission to humans and other animals. In view of the results, the conclusion is that the environment analyzed is contaminated by parasitic forms, constituting a serious public health problem. Therefore, implementing educational and preventive measures in the community to control parasites is of crucial importance.

Chemical composition and cytotoxicity of extracts of marjoram and rosemary and their activity against Sporothrix brasiliensis

PURPOSE

Motivated by increasing reports of antifungal resistance in human and animal sporotrichosis, this study evaluated the chemical composition, cytotoxicity and anti-Sporothrix brasiliensis activity of extracts of marjoram (Origanum majorana) and rosemary (Rosmarinus officinalis).

METHODOLOGY

Ten (INF10) and 60 min (INF60) infusions, a decoction and a hydroalcoholic extract (HAE, 70 %) were prepared from both plants (10 % w/v). The extract composition was analysed by liquid chromatography/mass spectrometry and the cytotoxicity was evaluated using a colorimetric assay in canine and feline kidney cells. Using a broth microdilution assay (CLSI M38-A2) adapted to the extracts, 30 Sporothrix brasiliensis isolates from dogs, cats and humans, and one Sporothrix schenckii were tested.Results/Key findings. The predominant phenolic compounds found in all extracts were 4-hydroxybenzoic acid, caffeic acid and chlorogenic acid. Luteolin was also one of the predominant compounds, but only in the HAE of marjoram. Extracts of marjoram maintained cell viability in concentrations up to 2.5 mg ml-1 for the feline cell line and up to 10 mg ml-1 for the canine cell line, whereas in rosemary, the cell viability for both kidney lines was maintained with concentrations up to 5 mg ml-1. The activity of rosemary extracts was low or absent. Among the marjoram extracts, HAE was highlighted and had fungistatic activity against Sporothrix brasiliensis (MIC5040 mg ml-1), including in all itraconazole-resistant isolates. S. schenckiisensu stricto was sensitive to marjoram extracts (MIC/MFC ≤5 mg ml-1), with the exception of INF10.

CONCLUSION

These findings support the potential usefulness of the HAE of marjoram in the treatment of sporotrichosis.

Plants from Lamiaceae family as source of antifungal molecules in humane and veterinary medicine

This work aimed to review the main plants of Lamiaceae family with activity against pathogenic fungi of medical and veterinary interest. Published studies in the main international databases between January 2002 and June 2016 showed that 55 botanical species belonging to 27 genus presented antifungal activity in different forms of extractions, mainly essential oils. Pathogenic fungi of Aspergillus spp., Candida spp., Malassezia spp., Cryptococcus spp., Sporothrix spp., Microsporum spp., Trichophyton spp. and Epidermophyton spp. genus were in vitro sensitive to several plants of Lamiaceae family. Chemical molecules isolated were described as promising use as antifungals in mycoses, highlighting estragole, 1,8-cineole, terpineol-4, γ-terpinene, among others. However, it should be alert to need of universal standardization in the laboratories tests with natural products.

First isolation of Dioctophyme renale eggs from an urban environment and identification of those from animal urine

Abstract Dioctophyme renale is a zoonotic parasite with worldwide distribution, although its occurrence is little known. The objective here was to evaluate the presence of parasite eggs in the environment and in the urine of dogs and cats in an urban area. Soil samples and urine were evaluated respectively by means of the Caldwell-Caldwell technique and urinalysis. Out of the 100 soil samples, 3% presented D. renale eggs, and out of the 43 urine samples, 18.6% were positive, including the feline samples. Thus, D. renale eggs are present in the urban environment, and dogs and cats are parasitized by this nematode, which therefore represents a risk to public health.

Dioctophyme renale (Nematoda: Enoplida) in domestic dogs and cats in the extreme south of Brazil

Abstract Dioctophyme renale is a zoonotic nematode that parasites the kidneys of wild and domestic carnivores, and it has been reported frequently in Brazil. The aim here was to register the number of cases of dogs and cats diagnosed with dioctophymosis by necropsy (1981 to 2014) and ultrasound examination (2010 to 2015) in Pelotas-RS. In this context, a survey was conducted on dioctophymosis cases diagnosed at the Veterinary Pathology Laboratory (LPV) and Veterinary Clinical Hospital (HCV) of the Federal University of Pelotas (UFPel), and at a specialist veterinary imaging diagnostics clinic. In total, 95 cases were registered. The high series of the disease in dogs can be related to the presence of a large number of stray and semi-domestic dogs in the city, and also due to the ingestion of intermediate hosts of D. renale parasitized with the infective larvae. Thus, it can be concluded that Pelotas is a city with favorable conditions for the occurrence of dioctophymosis with high rate of disease in recent years.

Germicidal activity of plant extracts of Origanum vulgare and Rosmarinus officinalis against Sporothrix schenckii complex

The literature shows that is a resistance by the microorganisms against commercial products used for the disinfection of contaminated environments. Due to this, the aim of this study was to evaluate the activity of the tincture, aqueous extract (decoction and infusion) and hydroalcoholic extract of Origanum vulgare and Rosmarinus officinalis, as an alternative to disinfectants, using the technique of direct exposure, against Sporothrix schenckii complex. For this, the direct exposure tests, with fungal isolates from clinical cases pertaining to dogs and cats with sporotrichosis, were used to evaluate the sensitivity of Sporothrix spp. against plants extracts, with the action evaluated in the times of 5, 10 and 15 minutes of exposure . As a positive control, it was used a sterile water solution containing innocuous and disinfectants used to control was sodium hypochlorite alcohol and 70°GL. As a result, it can be shown the sensitivity of the fungal isolates front to tincture of Origanum vulgare and Rosmarinus officinalis and hydroalcoholic extract of Origanum vulgare at all times of exposure, in 10% concentration of the extract.

Cytotoxicity and anti-Sporothrix brasiliensis activity of the Origanum majorana Linn. oil

The study aimed to evaluate the anti-Sporothrix sp. activity of the essential oil of Origanum majorana Linn. (marjoram), its chemical analysis, and its cytotoxic activity. A total of 18 fungal isolates of Sporothrix brasiliensis (n: 17) from humans, dogs and cats, and a standard strain of Sporothrix schenckii (n: 1) were tested using the broth microdilution technique (Clinical and Laboratory Standard Institute – CLSI M27-A3) and the results were expressed in minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC). The MIC₅₀ and MIC₉₀ of itraconazole against S. brasiliensis were 2 μg/mL and 8 μg/mL, respectively, and the MFC₅₀ and MFC₉₀ were 2 μg/mL and >16 μg/mL, respectively, with three S. brasiliensis isolates resistant to antifungal. S. schenckii was sensitive at MIC of 1 μg/mL and MFC of 8 μg/mL. For the oil of O. majorana L., all isolates were susceptible to MIC of ≤2.25–9 mg/mL and MFC of ≤2.25–18 mg/mL. The MIC₅₀ and MIC₉₀ were ≤2.25 mg/mL and 4.5 mg/mL, respectively, and the MFC_50/90 values were twice more than the MIC. Twenty-two compounds were identified by gas chromatography with a flame ionization detector (CG-FID) and 1,8-cineole and 4-terpineol were the majority. Through the colorimetric (MTT) assay, the toxicity was observed in 70–80% of VERO cells between 0.078 and 5 mg/mL. For the first time, the study demonstrated the satisfactory in vitro anti-Sporothrix sp. activity of marjoram oil and further studies are needed to ensure its safe and effective use.

Anti- Sporothrix spp. activity of medicinal plants

ABSTRACT Cases of sporotrichosis in humans and animals without satisfactory clinical response have increased, a warning sign of strains resistant to conventional antifungal agents. The urgent search for alternative therapies was an incentive for research on medicinal plants with anti-Sporothrix spp. properties. A bibliographic survey was performed based on scientific papers about in vitro and in vivo antifungal activity of essential oils and extracts of plants in differents solvents against the fungal of the Sporothrix schenckii complex. The study methodology consisted of a literature review in Google Scholar, Science Direct, Pubmed, Bireme and Springer link with papers from 1986 to 2015. We found 141 species of plants that were investigated, of which 100 species were concentrated in 39 botanical families that had confirmed anti-Sporothrix activity. Combretaceae, Asteraceae and Lamiaceae represented the botanical families with the greatest number of plants species with antifungal potential, using different methodologies. However, there are few studies with medicinal plants in experimental infection in animals that prove their activity in the treatment of sporotrichosis. It reinforces the need for further research related to standardization of in vitro methodologies and in vivo studies related to safety and to toxicity potential of these plants with anti-Sporothrix spp. activity.

VALOR DIAGNÓSTICO DO HEMOGRAMA, UROCULTURA E HEMOCULTURA NA CANDIDOSE EXPERIMENTAL SISTÊMICA

O presente estudo avaliou hemograma, proteínas plasmáticas totais (PPT), hemocultura e urocultura de ratas Wistar com candidose experimental sistêmica. Os animais foram inoculados com Candida albicans e acompanhados por 30 dias. A coleta de sangue e urina foi feita durante as necropsias. No eritrograma, 11,1% apresentaram anemia e 44,4% policitemia, enquanto que as PPT estavam aumentadas em 11,1% dos ratos. Em relação ao leucograma, 88,9% apresentaram leucopenia por neutropenia e linfopenia. Os neutrófilos segmentados tiveram um aumento dos valores relativos (28-48%) em 66,7% dos animais quando comparados aos outros do grupo experimental (8-15%). A cultura da urina apresentou-se positiva em 33% das amostras e a do sangue em 25%, sendo que somente um animal com candidúria não apresentou hemocultura positiva. Os resultados demonstram que o hemograma completo, a urucultura e a hemocultura apresentaram-se de pouco valor no diagnóstico específico de candidose sistêmica experimental. Análises seriadas podem aumentar as chances de uro-hemoculturas positivas, e assim possibilitar a instituição de terapêutica precoce que possa beneficiar o paciente, e assim melhorar o prognóstico. 

The use of (1-3) β-glucan along with itraconazole against canine refractory sporotrichosis

Sporotrichosis, caused by the Sporothrix schenckii fungal complex, is a zoonotic mycosis distributed worldwide. Itraconazole is the treatment of choice for domestic animals although some fungal isolates have shown resistance to this drug. The objective of this study was to report, for the first time, the use of (1-3) β-glucan along with itraconazole in the treatment of a canine with sporotrichosis caused by Sporothrix brasiliensis. The animal had ulcerated and crusted lesions, especially on the nasal planum. Clinical samples were collected for a complete blood count, cytological analysis of the lesion, and fungal culture. Based on the results of the laboratory examination, and after the fungal culture, antibiotic therapy and treatment with itraconazole were initiated. Two additional fungal cultures were performed, which were positive. After 7 months of the animal treatment with itraconazole, the S. brasiliensis culture was still positive, so that the itraconazole was associated with (1-3) β-glucan. After four weekly applications of glucan, the complete elimination of the fungus was observed based on the fungal culture negative results. The results show, therefore, that (1-3) β-glucan with itraconazole promoted the case resolution, and it may be considered a promising alternative for the treatment of sporotrichosis in cases of resistance to conventional therapy.

Clinical and mycological analysis of dog's oral cavity

The oral microbiota of humans and animals is made up of a wide variety of yeasts and bacteria, but microbiota of dogs is not totally described. Although such identification is an important step to establish the etiopathogenesis and adequate therapy for the periodontal disease The aim of this study was to evaluate and correlate oral alterations with the presence of yeasts in oral cavity of female dogs. After clinical evaluation samples from healthy and from dogs with oral diseases were obtained from three different oral sites by swabs, curettes, millimeter periodontal probes and HA membrane tip in cellulose ester. Yeast identification was performed through macroscopic and microscopic colony features and biochemical tests. Dental calculus was the most prevalent occurrence in the oral cavity of 59 females. However, the isolation of yeasts was significantly higher (p < 0.05) in animals suffering from halitosis. Eleven yeast species were identified, namely: Malassezia pachydermatis, Rhodotorula spp., Candida albicans, C. catenulata, C. famata, C. guilliermondii, C. parapsilosis, C. intermedia, Trichosporon asahii, T. mucoides and Cryptococcus albidus. It could be concluded that the yeasts are part of the microbiota from the different sites of the oral cavity of the female canines studied without causing any significant alterations except halitosis.

[Occurrence of Cryptococcus neoformans in pigeon excrement in the city of Pelotas, State of Rio Grande do Sul]

INTRODUCTION

Cryptococcus neoformans is an encapsulated yeast and is the etiological agent for human and animal cryptococcosis. It is found in sources within the environment, including pigeon excrement, and is an important cause of mortality among immunocompromised individuals worldwide.

METHODS

Seventy different environments in the city of Pelotas, Rio Grande do Sul, were surveyed for the purpose of investigating Cryptococcus neoformans occurrences in pigeon excreta. The environments included buildings, public squares and outdoor locations in the city. After collection, chloramphenicol saline solution was added to the excreta, which were then homogenized and seeded onto Sabouraud agar with chloramphenicol and onto Niger agar, and incubated at 32 degrees C. Identification was performed by direct examination and by means of the phenoloxidase and urease tests, carbohydrate assimilation and culturing in CGB medium.

RESULTS

Out of the sites investigated (n = 70), 26 (37.1%) of them contained pigeon excreta. These included historical buildings (n = 8), a church tower (n = 1), rice mills and warehouses (n = 7), a public square (n = 1) and outdoor locations (n = 9). Cryptococcus neoformans was isolated from 26.9% (n = 7/26) of these locations.

CONCLUSIONS

This study draws attention to isolation of this fungus in urban areas that present large accumulations of pigeon excrement. This represents a risk to public health, especially for immunocompromised individuals.

[Experimental cutaneous sporotrichosis: in vivo evaluation of itraconazole and terbinafine]

The aim of this study was to evaluate the in vivo activity of itraconazole and terbinafine for treating experimental cutaneous sporotrichosis. Eighty Wistar rats were used, divided into four groups (TERB20, TERB30, ITRA and CONT). They were inoculated in the left plantar pad with 0.2 ml of solution containing 2x10(3) cell/ml of Sporothrix schenckii and treated with terbinafine (20 and 30 mg/kg), itraconazole (10 mg/kg) or placebo for 13 weeks. The lesions at the inoculation site were evaluated and measured weekly, along with their dissemination. Mycological and histopathological analyses were performed subsequently. The results showed that the animals in the ITRA group differed statistically in all parameters evaluated, in relation to CONT. For terbinafine, there were no statistical differences between the treated and control groups. It could be confirmed that itraconazole presented good activity for treating sporotrichosis, while terbinafine was ineffective for this disease at the doses used. However, more studies on the latter antifungal agent are needed.

In vitro activity of origanum vulgare essential oil against candida species

The aim of this study was to evaluate the in vitro activity of the essential oil extracted from Origanum vulgare against sixteen Candida species isolates. Standard strains tested comprised C. albicans (ATCC strains 44858, 4053, 18804 and 3691), C. parapsilosis (ATCC 22019), C. krusei (ATCC 34135), C. lusitaniae (ATCC 34449) and C. dubliniensis (ATCC MY646). Six Candida albicans isolates from the vaginal mucous membrane of female dogs, one isolate from the cutaneous tegument of a dog and one isolate of a capuchin monkey were tested in parallel. A broth microdilution technique (CLSI) was used, and the inoculum concentration was adjusted to 5 x 10⁶ CFU mL^-1. The essential oil was obtained by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography. Susceptibility was expressed as Minimal Inhibitory Concentration (MIC) and Minimal Fungicidal Concentration (MFC). All isolates tested in vitro were sensitive to O. vulgare essential oil. The chromatographic analysis revealed that the main compounds present in the essential oil were 4-terpineol (47.95%), carvacrol (9.42%), thymol (8.42%) and □-terpineol (7.57%). C. albicans isolates obtained from animal mucous membranes exhibited MIC and MFC values of 2.72 μL mL^-1 and 5 μL mL^-1, respectively. MIC and MFC values for C. albicans standard strains were 2.97 μL mL^-1 and 3.54 μL mL^-1, respectively. The MIC and MFC for non-albicans species were 2.10 μL mL^-1 and 2.97 μL mL^-1, respectively. The antifungal activity of O. vulgare essential oil against Candida spp. observed in vitro suggests its administration may represent an alternative treatment for candidiasis.

Comparação da técnica de microdiluição em caldo e ETEST para o cetoconazol frente à Malassezia pachydermatis

Malassezia pachydermatis é reconhecida como um habitante normal e patógeno oportunista do meato acústico externo e da pele de cães e gatos. Em condições clínicas especiais e em casos de falha terapêutica relatada em otite externa e dermatite complicada por esta levedura, é recomendado o teste de suscetibilidade antifúngica. Existem diferentes métodos de avaliação da suscetibilidade da levedura frente a antifúngicos em laboratório, alguns métodos comerciais e outros previamente padronizados pelo CLSI (NCCLS, 2002). O objetivo deste estudo foi o de avaliar a suscetibilidade de 17 amostras de M. pachydermatis proveniente de otite externa canina por meio de duas técnicas in vitro de antifungigramas: o Etest® e a microdiluição em caldo (MC) com o cetoconazol. A media da Concentração Inibitória Mínima (CIM) observada entre as 17 amostras foram 0.103mg/mL para o ETEST e 0.0012mg/mL para a MC variando de 0.004 a 0.75mg/mL no ETEST e entre 0.0019 e 0.03mg/mL na MC usando as mesmas amostras. Pelo ETEST, duas (11.8%) amostras foram resistentes, oito (47.1%) sensíveis e sete (41.1%) mostraram sensibilidade intermediária. Na MC foram observadas quatro (23.5%) amostras resistentes, sete (41.2%) sensíveis e seis (35.3%) amostras com sensibilidade intermediária. Apesar das porcentagens de sensibilidade serem semelhantes pelas duas técnicas, os resultados de CIM não correspondem na uma mesma amostra. Estes resultados mostraram que há uma urgente necessidade de padronização dos valores considerados como parâmetros para inibição do crescimento da levedura. Portanto, um método simples e eficiente deveria ser usado rotina na prática de laboratório.

Efficacy of terbinafine and itraconazole on a experimental model of systemic sporotrichosis

Itraconazole is currently considered the drug of choice to treat the diverse clinical presentation of sporotrichosis. On the other hand terbinafine by virtue of its excellent in vitro activity is under comparative evaluation for its therapeutic potential for a wide range of fungal infections. In this study, our aim was to determine the in vivo efficacy of terbinafine and itraconazole on a experimental model of systemic sporotrichosis. 120 rats Wistar received an injection of 2×10³S. schenckii cells by via the lateral tail vein. After 3 days the animals were treated with terbinafine (250mg/kg) and itraconazole (100 mg/kg) and their respective diluents. In our model, terbinafine and itraconazole were effective in reducing the number of clinical lesions and positive organ cultures. There was statistical difference between the groups treated with the antifungals in relation to the control groups (p<0,05) concerning the clinical alterations, anatomic-pathological findings and in the positive organ cultures of the agent, being that the treated animals resulted in the absence and/or reduction of all the evaluated parameters. As for the treatments, terbinafine showed similar or higher activity that itraconazole in the evaluation of the testicle alteration (p=0,0004), as well as in the positive organ cultures of microorganism from the organ (p=0,0142). With these results it is possible to conclude that the antifungals studied are effective in the treatment of experimental systemic sporotrichosis.

Contaminação do ar por Aspergillus em ambiente de reabilitação de animais marinhos

Espécies fúngicas do gênero Aspergillus são frequentemente associadas com alta mortalidade de aves marinhas em cativeiro. Tendo em vista que a aspergilose geralmente é adquirida pela inalação dos propágulos fúngicos presentes no ar, o estudo objetivou avaliar a qualidade do ar quanto às espécies de Aspergillus, das instalações internas de um centro de reabilitação de animais marinhos que frequentemente recebe pingüins, gaivotas, albatrozes e petréis acometidos por alguma moléstia. Oitenta e um dias de colheitas foram realizados distribuídos em um período de aproximadamente dois anos, através da exposição de placas de Petri contendo Agar Sabouraud dextrose acrescido de cloranfenicol no ambiente, as quais foram posteriormente incubadas a 25ºC. As colônias identificadas como pertencentes ao gênero Aspergillus, foram classificadas quanto à espécie através da avaliação macro e micro morfológica associada a uma chave de identificação. Foram obtidos 43 isolados classificados em sete espécies distintas, sendo A. fumigatus a predominante correspondendo a 27,9%, seguida de A. niger, A. flavus e outras quatro espécies de Aspergillus sp., demonstrando que as aves marinhas estão expostas a espécies fúngicas com potencial patogênico, o que enfatiza a necessidade de um controle microbiológico no ambiente onde são mantidos os animais em cativeiro.

[In vitro susceptibility of isolates of Sporothrix schenckii to terbinafine and itraconazole]

The study objective was to determine the in vitro activity of terbinafine and itraconazole through the microdilution technique in broth (NCCLSM27-A2), adapted for dimorphic fungus, in relation to 12 isolates of Sporothrix schenckii. Six were from feline sporotrichosis, three from human sporotrichosis, one from a dog and two from human isolates originating from Instituto Oswaldo Cruz. The inoculum and antifungal concentrates were distributed on microplates that were incubated at 35 degrees C for five days. Minimum inhibitory concentration readings were made at the end of this period. The MIC for terbinafine ranged from 0.055 microg/ml to 0.109 microg/ml, and the MIC for itraconazole ranged from 0.219 microg/ml to 1.75 microg/ml. For both drugs, the MIC from the isolates from IOC was 0.875 microg/ml. The present study demonstrates the high susceptibility of Sporothrix schenckii to terbinafine. Further studies to correlate the in vitro susceptibility tests with the clinical response of patients with sporotrichosis are needed.

Adjuvant effect of green propolis on humoral immune response of bovines immunized with bovine herpesvirus type 5

Despite recent technological advances in vaccine production, most vaccines depend on the association with adjuvant substances. In this study, propolis, which has been attracting the attention of researchers due to its bioactive properties, was evaluated as an immunological adjuvant. The association of 40mg/dose of an ethanolic extract of green propolis with an inactivated oil vaccine against bovine herpesvirus type 5 (BoHV-5), resulted in a significant increase (P<0.01) in the neutralizing antibody levels, comparing to the bovines that received the same vaccine without propolis. Besides, propolis increased the percentage of animals with high antibody titers (above 32). Phenolic compounds such as artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) and the derivatives of cinnamic acid besides other flavonoid substances were abundant in the propolis extract used, and they could be the main substances with adjuvant action. The effect of the green propolis extract on the humoral immune response can be exploited in the development of new vaccines.

Differences in virulence between isolates of feline Sporotrichosis

Sporotrichosis is a chronic subcutaneous mycosis caused by Sporothrix schenckii. This work aimed to evaluate the virulence of two different isolates of S. schenckii from cutaneous (CUT) and systemic (SYS) forms of feline sporotrichosis. A standard inoculum with 2 x 10(3) yeast cells/ml was prepared from each of the isolates. The experimental infection was carried out with 0.1 ml of the inoculum from both isolates and then injected in the paw pads of Swiss albino mice of groups CUT and SYS. The clinical evolution of the disease and the diameter of the lesion at the inoculated sites were evaluated during nine weeks. Four necropsies were done to collect material from the lesions (p < 0.01). Group CUT demonstrated a more evident clinical evolution of the disease from week two to week five; large lesions in the paw pad on week four (p < 0.01); and a higher incidence of lesions in other parts of the body (p < 0.01) than group SYS (p < 0.01). S. schenckii was isolated from the inoculated site in groups SYS and CUT until days 30 and 45, respectively. Granulomas with yeast cells usually localized in the central area were observed in histopathology sections on days 15 and 30 post-inoculations. Those yeast cells decreased on day 45 being absent on day 62 when tissue repair initiated. The results showed that distinct clinical isolates of S. schenckii cause significant differences in the clinical evolution of sporotrichosis.