Schinus molle essential oil as a potential source of bioactive compounds: antifungal and antibacterial properties.

AIMS: The study was focused on the evaluation of antimicrobial activity in vitro of the essential oil (EO) of leaves from Schinus molle against bacteria and fungi of clinical importance in the search for the discovery of new active compounds. METHODS AND RESULTS: The chemical composition of the S. molle EO was determined by gas chromatography/mass spectrometry and its antimicrobial effect was verified by broth microdilution method. The major compounds found were ß-pinene (25·23%), epi-α-cadinol (21·29%), α-pinene (18·72%), myrcene (11·54%) and sabinene (5·02%). The EO showed significant antifungal activity against Paracoccidioides brasiliensis (39·06 µg ml-1 ), weak action against Cryptococcus neoformans (625 µg ml-1 ) and Trichophyton quinckeanum (625 µg ml-1 ) and was inactive against Candida sp. In the analysis of the antibacterial action, the micro-organisms tested did not show sensitivity. CONCLUSIONS: This study showed a promising result of S. molle volatiles against the fungus P. brasiliensis, which causes paracoccidioidomycosis (PCM), a systemic mycosis of great clinical importance in Latin America. SIGNIFICANCE AND IMPACT OF THE STUDY: The results found here are novel and encourage investigations of the compounds present in this EO, which represents a source of molecules with potential use in the treatment of PCM.

PRP8 intein in dermatophytes: Evolution and species identification.

Dermatophytes are keratinophilic fungi belonging to the family Arthrodermataceae. Despite having a monophyletic origin, its systematics has always been complex and controversial. Sequencing of nuclear ribosomal ITS and D1/D2 rDNA has been proposed as an efficient tool for identifying species in this group of fungi, while multilocus analyses have been used for phylogenetic species recognition. However, the search for new markers, with sequence and size variation, which enable species identification in only one polymerase chain reaction (PCR) step, is very attractive. Inteins seems to fulfill these characteristics. They are self-splicing genetic elements present within housekeeping coding genes, such as PRP8, that codify the most important protein of the spliceosome. The PRP8 intein has been described for Microsporum canis in databases but has not been studied in dermatophytes in any other published work. Thus, our aim was to determine the potential of this intervening element for establishing phylogenetic relationships among dermatophytes and for identifying species. It was found that all studied species have a full-length PRP8 intein with a Homing Endonuclease belonging to the family LAGLIDADG. Phylogenetic analyses were consistent with other previous phylogenies, confirming Epidermophyton floccosum in the same clade of the Arthroderma gypseum complex, Microsporum audouinii close to M. canis, differentiating A. gypseum from Arthroderma incurvatum, and in addition, better defining the Trichophyton interdigitale and Trichophyton rubrum species grouping. Length polymorphism in the HE region enables identification of the most relevant Microsporum species by a simple PCR-electrophoresis assay. Intein PRP8 within dermatophytes is a powerful additional tool for identifying and systematizing dermatophytes.

Microbiological evaluation of different strategies for management of snakes in captivity.

Keeping snakes in captivity to produce venom for scientific research and production of inputs is now a worldwide practice. Maintaining snakes in captivity involves capture, infrastructure investments, management techniques, and appropriate qualified personnel. Further, the success of the project requires knowledge of habitat, nutrition, and reproduction, and control of opportunistic infections. This study evaluated the management of snakes in three types of captivity (quarantine, intensive, and semiextensive) and diagnosed bacterial and fungal contaminants. A bacteriological profile was obtained by swabbing the oral and cloacal cavities, scales, and venoms of healthy adult snakes from Bothrops jararaca (Bj) and Crotalus durissus terrificus (Cdt). There was predominance of Enterobacteriaceae, especially non-fermenting Gram-negative bacilli excluding Pseudomonas spp and Gram- positive bacteria. Statistically, intensive captivity resulted in the highest number of bacterial isolates, followed by recent capture (quarantine) and by semiextensive captivity. No statistical difference was found between Bj and Cdt bacterial frequency. In vitro bacterial susceptibility testing found the highest resistance against the semisynthetic penicillins (amoxicillin and ampicillin) and highest sensitivity to amicacin and tobramycin aminoglycosides. To evaluate mycological profile of snakes from intensive captivity, samples were obtained from two healthy Bj and one B. moojeni, one B. pauloensis, and one Cdt showing whitish lesions on the scales suggestive of ringworm. Using conventional methods and DNA-based molecular procedures, five samples of Trichosporon asahii were identified. Despite the traditional role of intense captivity in ophidian venom production, semiextensive captivity was more effective in the present study by virtue of presenting superior control of bacterial and fungal transmission, easier management, lowest cost, and decreased rate of mortality; therefore, it should be considered as a good alternative for tropical countries.

Candidemia in a brazilian tertiary hospital: microbiological and clinical features over a six-year period

Yeasts are becoming a common cause of nosocomial fungal infections in immunocompromised patients. Such infections often develop into sepsis with high mortality rates. The aim of this study was to evaluate some of the numerous factors associated with the development of candidemia. Medical records were retrospectively analyzed of 98 Candida spp. patients. Results showed that the most prevalent risk factors for developing candidemia were: antibiotics and antifungal agents (93.9% and 79.6%, respectively); the use of central venous catheter (93.9%); mechanical ventilation (73.5%); and parenteral nutrition (60.2%). The main species of Candida found were: C. parapsilosis (37.76%), C. albicans (33.67%); and others (28.57%). C. glabrata showed the highest mortality rate (75%), followed by C. tropicalis (57.1%) and C. albicans (54.5%). The elevated mortality rate found in this study indicates that preventive measures against candidemia must be emphasized in hospitals.(AU)

Candida spp: manual identification (reference method) and automated identification (Vitek system platform)

Yeasts are becoming a common cause of nosocomial fungal infections that affect immunocompromised patients. Such infections can evolve into sepsis, whose mortality rate is high. This study aimed to evaluate the viability of Candida species identification by the automated system Vitek-Biomerieux (Durham, USA). Ninety-eight medical charts referencing the Candida spp. samples available for the study were retrospectively analyzed. The system Vitek-Biomerieux with Candida identification card is recommended for laboratory routine use and presents 80.6% agreement with the reference method. By separate analysis of species, 13.5% of C. parapsilosis samples differed from the reference method, while the Vitek system wrongly identified them as C. tropicalis, C. lusitaneae or as Candida albicans. C. glabrata presented a discrepancy of only one sample (25%), and was identified by Vitek as C. parapsilosis. C. guilliermondii also differed in only one sample (33.3%), being identified as Candida spp. All C. albicans, C. tropicalis and C. lusitaneae samples were identified correctly.

Road-killed wild animals: a preservation problem useful for eco-epidemiological studies of pathogens

Road-killed wild animals have been for years used for surveillance of vectors of zoonotic pathogens and may offer new opportunities for eco-epidemiological studies. In the current study, fungal infection was evaluated by PCR and nested-PCR in tissue samples collected from 19 road-killed wild animals. The necropsies were carried out and samples were collected for DNA extraction. Results, using PCR with a panfungal primer and nested PCR with specific primers, indicated that some animals are naturally infected with Amauroascus aureus, Metarhizium anisopliae, Aspergillus flavus, Aspergillus oryzae, Emmonsia parva, Paracoccidioides brasiliensis or Pichia stipitis. The approach employed herein proved useful for detecting the environmental occurrence of several fungi, as well as determining natural reservoirs in wild animals and facilitating the understanding of host-pathogen relationships.

Comparison of infection by brucella spp: in free-ranging and captive wild animals from São Paulo State, Brazil

The aim of the current study was to evaluate the infection rate by Brucella spp. in wild and in captive animals. Serum samples from 121 animals (94 free-ranging and 27 captive) of different mammal species were evaluated. Sera were submitted to rose Bengal test (RBT) for screening and serum agglutination tests (SAT) and 2-mercaptoethanol test (2-ME) for confirmatory results. Nine animals (five free-ranging and four captive) tested positive in RBT, but negative in the confirmatory tests. Several domestic animal diseases that have control programs are not focused on wild reservoirs, such as brucellosis in Brazil. The study of new reservoirs in wildlife is essential to prevent emerging diseases.

Virulence attenuation and phenotypic variation of Paracoccidioides brasiliensis isolates obtained from armadillos and patients.

Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most important systemic mycosis in Latin America. The virulence profiles of five isolates of P. brasiliensis were studied in two different moments and correlated with some colonial phenotypic aspects. We observed a significant decrease in the virulence and an intense phenotypic variation in the mycelial colony. The recognition of all ranges of phenotypic and virulence variation of P. brasiliensis, as well as its physiological and genetic basis, will be important for a better comprehension of its pathogenic and epidemiological features.

Virulence attenuation and phenotypic variation of Paracoccidioides brasiliensis isolates obtained from armadillos and patients

Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis, the most important systemic mycosis in Latin America. The virulence profiles of five isolates of P. brasiliensis were studied in two different moments and correlated with some colonial phenotypic aspects. We observed a significant decrease in the virulence and an intense phenotypic variation in the mycelial colony. The recognition of all ranges of phenotypic and virulence variation of P. brasiliensis, as well as its physiological and genetic basis, will be important for a better comprehension of its pathogenic and epidemiological features.

High frequency of Paracoccidioides brasiliensis infection in armadillos (Dasypus novemcinctus): an ecological study.

The fungus Paracoccidioides brasiliensis has been isolated from nine-banded armadillos (Dasypus novemcinctus) in different regions where paracoccidiodomycosis (PCM) is endemic. The link between PCM and these animals has provided the first valuable clue in the effort to elucidate the ecological niche of P. brasiliensis. The present study was aimed at correlating P. brasiliensis infection in armadillos with local ecological features and, if possible, the presence of the fungus in the soil in the Botucatu hyperendemic area of PCM. In this region the mean temperature ranges from 14.8 to 25.8 degrees C and the annual average precipitation is 1520 mm. The sites where 10 infected animals (positive group) were collected were studied and compared with the sites where five uninfected animals were found. The occurrence of the fungus in soil samples collected from the positive armadillos' burrows and foraging sites was investigated by the indirect method of animal inoculation. Environmental data from the sites of animal capture, such as temperature, rainfall, altitude, vegetation, soil composition, presence of water and proximity of urban areas, were recorded. All 37 soil samples collected from the sites had negative fungal cultures. Positive animals were found much more frequently in sites with disturbed vegetation, such as riparian forests and artificial Eucalyptus or Pinus forests, in altitudes below 800 m, near water sources. The soil type of the sites of positive animals was mainly sandy, with medium to low concentrations of organic matter. The pH was mainly acidic at all the sites, although the concentrations of aluminum cations (H+Al) were lower at the sites where positive animals were found. Positive armadillos were also captured in sites very close to urban areas. Our data and previous studies indicate that P. brasiliensis occurs preferentially in humid and shady disturbed forests in a strong association with armadillos.

Virulence profiles of ten Paracoccidioides brasiliensis isolates obtained from armadillos (Dasypus novemcinctus).

Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most important systemic mycosis in Latin America. The armadillo, Dasypus novemcinctus, has been confirmed as the primary natural reservoir of this fungus. Its geographic distribution is similar to that of human PCM. In this study, virulence profiles of 10 P. brasiliensis isolates from different armadillos and of two clinical isolates were tested in an experimental hamster model. Pathogenicity was evaluated by counting cfu and performing histopathological analysis in the testis, liver, spleen and lung. Circulating specific antibodies were measured using enzyme-linked immunosorbent assay (ELISA). All isolates from armadillos were virulent in the model, with dissemination to many organs. The clinical isolates, which had long been stored in cultured collections, were less virulent. The isolates were classified into four virulence categories according to number of cfu per gram of tissue: very high, high, intermediate and low. This study confirms that armadillos harbor pathogenic genotypes of P. brasiliensis, probably the same ones that infect humans.

Cerebriform colonies of Paracoccidioides brasiliensis isolated from nine-banded armadillos (Dasypus novemcinctus) at room temperature.

Twelve isolates of Paracoccidioides brasiliensis generated cerebriform colonies at room temperature on potato glucose agar slants (PDA). These isolates contained abundant chlamydospores and yeast-like cells and are a subset of the 65 isolates obtained from nine-banded armadillos (Dasypus novemcinctus). They grew as a yeast form with typical multiple buddings at 37 degrees C on brain heart infusion agar supplemented with 1% glucose. After replating on PDA and culturing at room temperature for 2 months, the mutants appeared as cottonous colonies, which indicated that the morphological characteristics were unstable.

A critical analysis of isolation of Paracoccidioides brasiliensis from soil.

The present review is a critical analysis of positive and negative reports of the isolation of Paracoccidioides brasiliensis from soil. The strains isolated from soil or soil-contaminated material (dogfood, penguin feces) by Batista et al. in Recife, Brazil, Negroni in the Argentinian Chaco, Albornoz in rural Venezuela, Silva-Vergara et al. in Ibiá, Brazil, Ferreira et al. in Uberlândia, Brazil, and Gezuele et al. at the Uruguayan base in the Antarctic region, presented mycological characteristics consistent with P. brasiliensis. In most of these studies, morphological characterization was complemented with an evaluation of virulence and antigenicity, and biochemical or molecular analysis. These isolations, therefore, can be considered true, supporting the concept of soil as an important element in the ecology of the pathogen. The large number of negative reports in attempts involving soil samples and the low repeatability of isolation of the fungus from the same area indicate that the specific conditions supporting growth of the pathogen in soil have not been fully clarified.

Clues to the presence of pathogenic fungi in certain environments.

The presence of various pathogenic fungi in rather unsuspected hosts and environments has always attracted the attention of the scientific community. Reports on the putative role of animals in fungal infections of humans bear important consequences on public health as well as on the understanding of fungal ecology. Fungi are ubiquitous in nature and their great capacity for adaptation allows them to survive and indeed, to thrive, in plants, trees and other natural substrata. Nonetheless, we are just beginning to learn the significance that these diverse fungal habitats have on the increasing number of immunosuppressed individuals. The accidental or permanent presence of fungi in animals, plants, soils and watercourses should not be taken too lightly because they constitute the source where potential pathogens will be contracted. If those fungal habitats that carry the largest risks of exposure could be defined, if seasonal variations in the production of infectious propagules could be determined, and if their mode of transmission were to be assessed, it would be possible to develop protective measures in order to avoid human infection. Additionally, unsuspected avenues for the exploration of fungal survival strategies would be opened, thus enhancing our capacity to react properly to their advancing limits. This paper explores several ecological connections between human pathogenic fungi and certain animals, trees, waterways and degraded organic materials. The occurrence of such connections in highly endemic areas will hopefully furnish more precise clues to fungal habitats and allow the design of control programs aimed at avoiding human infection.

Isolation of Paracoccidioides brasiliensis from armadillos (Dasypus noveminctus) captured in an endemic area of paracoccidioidomycosis.

Paracoccidioides brasiliensis, the causative agent of paracoccidioidomycosis (PCM), was first isolated from armadillos from the Amazonian region where the mycosis is uncommon. In the present study, we report on the high incidence of PCM infection in armadillos from a hyperendemic region of the disease. Four nine-banded armadillos (Dasypus novemcinctus) were captured in the endemic area of Botucatu, Sao Paulo, Brazil, killed by manual cervical dislocation and autopsied under sterile conditions. Fragments of lung, spleen, liver, and mesenteric lymph nodes were processed for histology, cultured on Mycosel agar at 37 degrees C, and homogenized for inoculation into the testis and peritoneum of hamsters. The animals were killed from week 6 to week 20 postinoculation and fragments of liver, lung, spleen, testis, and lymph nodes were cultured on brain heart infusion agar at 37 degrees C. Paracoccidioides brasiliensis was isolated from three armadillos both by direct organ culture and from the liver, spleen, lung, and mesenteric lymph nodes of hamsters. In addition, one positive armadillo presented histologically proven PCM disease in a mesenteric lymph node. The three armadillos isolates (Pb-A1, Pb-A2, and Pb-A4) presented thermodependent dimorphism, urease activity, and casein assimilation, showed amplification of the gp43 gene, and were highly virulent in intratesticularly inoculated hamsters. The isolates expressed the gp43 glycoprotein, the immunodominant antigen of the fungus, and reacted with a pool of sera from PCM patients. Taken together, the present data confirm that armadillos are a natural reservoir of P. brasiliensis and demonstrate that the animal is a sylvan host to the fungus.

Comparison between human and armadillo Paracoccidioides brasiliensis isolates by random amplified polymorphic DNA analysis.

Sixty-three Paracoccidioides brasiliensis isolates obtained from three nine-banded armadillos (Dasypus novemcinctus), one Amazonian armadillo's and 19 clinical isolates were compared by random amplified polymorphic DNA analysis with the primer OPG-19. The isolates were divided into three major clusters, I, II and III. Coincidences between human and armadillo isolates were observed in clusters I and II. Cluster III consisted only of armadillos' isolates. The results suggested that (I) humans may acquire P. brasiliensis infection by contact with armadillo's environment, (II) there may be P. brasiliensis genotypes peculiar to the animal, and (III) individual armadillos may be infected with P. brasiliensis cells with different genotypes.

Pathogenicities and GP43kDa gene of three Paracoccidioides brasiliensis isolates originated from a nine-banded armadillo (Dasypus novemcinctus).

We studied three different isolates of Paracoccidioides brasiliensis obtained from the mesenteric lymph node (D3LY1), the spleen (D3S1) and the liver (D3LIV1) of the same armadillo (Dasypus novemcinctus). Pulmonal inflammatory area was evaluated by intravenous inoculation of 10(6) yeast cells of each isolates in young, male, ddY mice. Moreover, the partial sequence of GP43kDa gene of P. brasiliensis was analyzed. The lung inflammatory area was greater in animals inoculated with isolate D3S1. The partial sequence of GP43kDa gene indicated that isolate D3S1 is different from isolates D3LY1 and D3LIV1. This study suggested that the same armadillo might be susceptible to multiple P. brasiliensis isolates simultaneously.

Paracoccidioides brasiliensis antigen batches from the same isolate show immunological and biochemical differences.

We investigated the occurrence of antigenic and biochemical variability among Paracoccidioides brasiliensis antigen batches prepared according to the same protocol. Initially (experiment #1), we analyzed two antigen lots of two human isolates (Bt1 & Bt2), cultured in two media (PYG: bactopeptone, yeast extract, glucose; MMM: McVeigh & Morton medium) in SDS-PAGE and in two immunological tests (immunodiffusion-ID and footpad swelling test-FPT). Afterwards (experiment #2), we compared the antigenic profile of three antigen batches from three human isolates (Bt1, Bt2 & Bt3) by two-dimensional immunoelectrophoresis (2 D-IEP) against a reference system for P. brasiliensis antigens. In experiment #1, there were important intra- and inter-strain antigenic differences between batches of the fungal isolates cultured on both media. The block titration of the antigen batches for the immunological tests revealed correlation between protein concentration and biological activity in ID and no correlation in FPT. In experiment #2, the reference system for P. brasiliensis showed 26 antigen peaks. There were important differences between batches prepared from the same isolate and between batches from different isolates. Our data suggested the occurrence of instability in the synthesis of antigenic components by a same P. brasiliensis isolate, under controlled incubation conditions.

Parameiosis in the entomopathogenic fungus Metarhizium anisopliae (METSH.) sorokin

Variaçöes no ciclo parasexual, especialmente relacionadas com instabilidade de diplóides já foram descritas em várias espécies de fungos. O processo foi chamado de "parameiose" e é caracterízado pelo aparecimento, a partir de heterocários, de recombinantes haplóides e diplóides além dos diplóides heterozigotos normalmente encontrados. Na presente investigaçäo um processo semelhante foi encontrado em Metarhizium anisopliae. Conídios obtidos de heterocários formados entre linhagens com marcadores genéticos apropriados foram semeados em meios seletivos e pelo menos três grupos de colônias foram obtidos. O primeiro deles consistiu de diplóides ou hiperhaplóides altamente estáveis que por semeadura de seus conídios produziram vários tipos de recombinantes haplóides. O segundo grupo era formado de recombinantes haplóides estáveis que devem ter-se originado de nucleos diplóides que sofreram um processo de haploidizaçäo dentro das hifas heterocariótícas antes de serem incorporadas aos conídios; e o terceiro grupo de colônias heterocarióticas as quais segregam apenas od tipos parentais. A parameiose já foi encontrada em várias espécies de Deuteromicetos e deve ter um papel importante no aumento da variabilidade genética desses fungos