Immune-mediated encephalitis and virilization in association with a mature cystic ovarian teratoma in an adolescent girl.

BACKGROUND: Mature cystic teratomas are the most common form of ovarian tumor in children and adolescents. These tumors are mostly benign and non-secreting. Virilization from an ovarian teratoma is exceptionally rare in pediatrics. Equally rare is the association of ovarian teratomas with auto-immune encephalitis. METHODS: We describe the case of a 15-year-old girl with menstrual abnormalities and virilization, who had a past medical history of encephalitis of an unknown etiology 16 months prior to presentation. RESULTS: Endocrine evaluation revealed an elevated serum testosterone and 17-hydroxy progesterone. A large left ovarian tumor was seen on a CT scan. Surgical excision revealed a mature cystic teratoma containing 6 liters of clear fluid with high androgen levels. Antibodies to the N-methyl-D-aspartate receptor of the hippocampus were detected in pre-operatively archived serum, but undetectable 6 months postoperatively. Immunohistochemistry studies on the tumor sections revealed that the antibodies in the patient's serum reacted with areas of the tumor expressing the N-methyl-D-aspartate receptor. Postoperatively, the patient's menstrual cycles became regular and her behavioral problems resolved. Her testosterone levels fell precipitously as well. CONCLUSION: Both virilizing mature cystic teratomas and teratoma-associated encephalitis are extremely rare in the pediatric population. We report on the first instance of these 2 rare entities occurring in the same patient.

Green Mold Diseases of Agaricus and Pleurotus spp. Are Caused by Related but Phylogenetically Different Trichoderma Species.

ABSTRACT Producers of champignon (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus) are facing recent incidents of green mold epidemics in Hungary. We examined 66 Trichoderma strains isolated from Agaricus compost and Pleurotus substrate samples from three Hungarian mushroom producing companies by a polymerase chain reaction-based diagnostic test for T. aggressivum, sequence analysis of the internal transcribed spacer region 1 (ITS1) and ITS2 and (selectively) of the fourth and fifth intron of translation elongation factor 1alpha (tef1alpha), and restriction fragment length polymorphism of mitochondrial DNA. Seven Trichoderma species were identified: T. aggressivum f. europaeum (17 isolates), T. harzianum (three isolates), T. longibrachiatum (four isolates), T. ghanense (one isolate), T. asperellum (four isolates), T. atroviride (nine isolates), and a still undescribed phylogenetic species, Trichoderma sp. DAOM 175924 (28 isolates). T. aggressivum f. europaeum was exclusively derived from A. bisporus compost, whereas Trichoderma sp. DAOM 175924 exclusively occurred in the substrate for Pleurotus cultivation. Sequences of the latter strains were co-specific with those for Trichoderma pathogens of P. ostreatus in Korea. The widespread occurrence of this new species raises questions as to why infections by it have just only recently been observed. Our data document that (i) green mold disease by T. aggressivum f. europaeum has geographically expanded to Central Europe; (ii) the green mold disease of P. ostreatus in Hungary is due to the same Trichoderma species as in Korea and the worldwide distribution of the new species indicates the possibility of spreading epidemics; and (iii) on mushroom farms, the two species are specialized on their different substrates.

Rapid identification of clinical Trichoderma longibrachiatum isolates by cellulose-acetate electrophoresis-mediated isoenzyme analysis.

Cellulose-acetate electrophoresis was used to investigate isoenzyme polymorphism among ten clinical and 11 non-clinical isolates of Trichoderma. Initial testing of 13 enzyme systems for activity and resolution of bands showed that seven were appropriate for identifying the different species. Each of the enzyme systems investigated (glucose-6-phosphate dehydrogenase, glucose-6-phosphate isomerase, 6-phosphogluconate dehydrogenase, peptidases A, B and D, and phosphoglucomutase) was diagnostic for at least one species. On the basis of the results of isoenzyme analysis, several isolates identified originally as Trichoderma pseudokoningii, T. koningii or T. citrinoviride were re-identified as T. longibrachiatum, in agreement with sequence analysis data for the internal transcribed spacer region of the isolates. The availability of a quick, inexpensive and reliable diagnostic tool for the identification of T. longibrachiatum isolates is important, as most clinical Trichoderma isolates belong to T. longibrachiatum. Furthermore, as many different enzyme systems are available, the method may also be suitable for the identification of other clinically relevant fungal species.

In vitro water activity and pH dependence of mycelial growth and extracellular enzyme activities of Trichoderma strains with biocontrol potential.

AIMS: Water activity (aw) and pH are probably the most important environmental parameters affecting the activities of mycoparasitic Trichoderma strains. Therefore it is important to collect information on the effects of these factors on mycelial growth and on the in vitro activities of extracellular enzymes involved in nutrient competition (e.g. beta-glucosidase, cellobiohydrolase and beta-xylosidase) and mycoparasitism (e.g. N-acetyl-beta-glucosaminidase, trypsin-like protease and chymotrypsin-like protease) of Trichoderma strains with biocontrol potential. METHODS AND RESULTS: Water activity and pH dependence of the linear mycelial growth of five examined Trichoderma strains belonging to three different species groups was examined on yeast extract and soil extract media. Maximal growth rates were observed at aw 0.997 and pH 4.0 in the case of all strains. The activities of the examined extracellular enzymes at different aw and pH values were determined spectrophotometrically after incubation with chromogenic p-nitrophenyl and p-nitroaniline substrates. Maximal enzyme activities were measured at aw 0.950 for beta-glucosidase, trypsin-like protease and chymotrypsin-like protease, at 0.910 for cellobiohydrolase and at 0.993 for beta-xylosidase and N-acetyl-beta-glucosaminidase enzymes. Optimal pH values are suggested to be at 5.0 for beta-glucosidase, cellobiohydrolase and N-acetyl-beta-glucosaminidase, at 3.0 for beta-xylosidase, at 6.0 for trypsin-like protease and between 6.0 and 7.0 for chymotrypsin-like protease activities, respectively. CONCLUSIONS: Extracellular enzymes of the examined mycoparasitic Trichoderma strains are able to display activities under a wider range of aw and pH values than those allowing mycelial growth. SIGNIFICANCE AND IMPACT OF THE STUDY: Data about the effects of aw and pH on mycelial growth and extracellular enzyme activities of Trichoderma reveal useful information about the applicability of biocontrol strains in agricultural soils with specific water and pH relations.

Changes in activity of extracellular enzymes in dual cultures of Lentinula edodes and mycoparasitic Trichoderma strains.

AIMS: The main problem that arises during the cultivation of Lentinula edodes, the Asian Shiitake mushroom, is that the logs on which the cultivation is performed are contaminated by competing micro-organisms, especially Trichoderma spp. The aim of this study was to examine the changes in activity of extracellular enzymes in dual cultures of Trichoderma spp. and L. edodes. METHODS AND RESULTS: Extracellular enzyme activities were determined spectrophotometrically. Trichoderma enzymes important for the degradation of fungal cell walls (N-acetyl-beta-glucosaminidase and laminarinase) were shown to be induced by inactive L. edodes mycelia in liquid culture. The changes that occurred in the extracellular enzyme activities of L. edodes and mycoparasitic Trichoderma spp. (T. aureoviride, T. harzianum and T. viride) were examined during antagonistic interactions on solid medium. The extracellular enzyme patterns of both partners proved to be altered. Trichoderma spp. were induced to produce N-acetyl-beta-glucosaminidase and laminarinase in the presence of active L. edodes mycelia, similarly as observed in liquid culture. The activities of both laccase and manganese peroxidase of L. edodes decreased after physical contact with active Trichoderma mycelia, possibly in consequence of the beginning of degradation of L. edodes by the Trichoderma enzymes. However, besides a decrease in manganese peroxidase activity, an enhancement of L. edodes laccase activity was observed on solid media containing crude culture fluids from Trichoderma liquid cultures. The metabolites responsible for these effects proved to be heat stable. CONCLUSIONS: Induction and inhibition of several extracellular enzymes of both partners were shown in dual cultures of L. edodes and Trichoderma strains, indicating the important role of these enzymes in the antagonistic interaction between the two species. SIGNIFICANCE AND IMPACT OF THE STUDY: As the main problem during the large-scale cultivation of L. edodes is the contamination of the growth substrate by Trichoderma mycelia, the particular knowledge of the mechanism of this competition might be relevant.

Breeding of mycoparasitic Trichoderma strains for heavy metal resistance.

AIMS: This study was designed to investigate the effects of 10 heavy metals on the in vitro activities of beta-glucosidase, cellobiohydrolase, beta-xylosidase and endoxylanase enzymes for six strains of Trichoderma, and to isolate and characterize heavy metal-resistant mutants. METHODS AND RESULTS: At a concentration of 1 mmol, only mercury showed significant inhibitory effects on the in vitro enzyme activities; in all other cases, the enzymes remained active. A total of 177 heavy metal-resistant mutants were isolated and tested for cross-resistance to other heavy metals. Some mutants were effective antagonists of Fusarium, Pythium and Rhizoctonia strains, even on media containing the respective heavy metals. CONCLUSION: Trichoderma strains could be developed as biocontrol agents that are effective against plant pathogenic fungi, even under heavy metal stress. SIGNIFICANCE AND IMPACT OF THE STUDY: Trichoderma mutants resistant to heavy metals might be of value for use with heavy metal-containing pesticides, as part of an integrated plant protection system.

Characterization of the extracellular enzyme systems of Trichoderma viride AH124.

A mycoparasitic Trichoderma viride strain was investigated for the production of extracellular enzymes important in antagonism, by using natural and chromogenic substrates. Some of these enzymes, such as beta-1,3-glucanases, and low levels of proteases were produced constitutively. Under inductive conditions, the measurable activities of beta-1,3-glucanase, protease and aspecific chitinase increased, while for the proteases and beta-1,3-glucanases, the levels depended on both the nitrogen and the carbon source. Gel filtration chromatography revealed at least 4 beta-1,3-glucanases, 6 proteases, 2 beta-glucosidases and 1 beta-1,4-N-acetyl-glucosaminidase izoenzyme under inductive conditions.

Influence of water potential on growth, enzyme secretion and in vitro enzyme activities of Trichoderma harzianum at different temperatures.

The influence of water potential on linear mycelial growth, secretion, and the in vitro activities of enzymes beta-glucosidase, cellobiohydrolase, beta-xylosidase, exochitinase, and chymotrypsin of Trichoderma harzianum strain T66 was studied at different temperatures. Nearly linear correlation was found between water potential and colony growth rate at both 25 degrees C and 10 degrees C, with higher growth rates at the higher temperature and higher water potentials. The amounts of enzyme secretion depended on the water potential and not on the quality of salt (NaCl or KCl) used as osmoticum. Enzyme activities were significantly affected by water potential. Significant enzyme activities were measured for most of the enzymes even at -14.800 megapascal (MPa), which is below the water potential where mycelial growth ceased. These results suggest the possibility of using mutants with improved xerotolerance for biocontrol purposes in soils with lower water potentials.