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[Hemoperfusion with coated activated charcoal for treating acute poisoning by remedies, plant protectants, and fungi. III. Fungi (author's transl)].

Four patients with foudroyant liver dystrophy due to ingestion of fungi of the Amanita phalloides species were treated by hemoperfusion with coated activated charcoal. Three patients survived the poisoning. One patient died in a coma due to hepatic disintegration with cardiac and respiratory insufficiency. One female patient suffering from hemolytic syndrome and acute anuresis due to ingestion of fungi of the Paxillus involutus species recovered completely after treatment of combinated hemodialysis and hemoperfusion. The first hemoperfusion in the patients with Amanita phalloides poisoning were performed two to three days after ingestion of the fungus. At that time there were only traces of amanitines in the blood of one of the surviving patients. These Amanita phalloides toxins were only detected in the first 24-hour urine in the other 3 patients. It is thus not to be expected that toxicologically relevant quanities of the toxins will be eliminated from the blood by hemoperfusion carried out two to three days following ingestion of the fungus, Amanita phalloides. No coherence of restitutio ad integrum and hemoperfusion could be pointed out in the female patients suffering from hemolytic syndrom and anuresis due to Paxillus involutus.

Adult

Incidence of antiprotozoal and antivermal antibiotics in fungi, V Class Fungi Imperfecti Collected in the Vietnamese Democratic Republic.

From soil samples collected in the jungles of Ninh Binh Province of the Vietnamese Democratic Republic, 97 isolates belonging to 54 species of Fungi imperfecti were obtained and screened for the production of antibiotics. The isolates were identified as belonging to the orders Melanconiales, Moniliales, Sphaeropsidales and Mycelia sterilia. In the species studied a very high incidence of antiprotozoal activities were observed.

Animals

Effect of cadmium on fungi and on interactions between fungi and bacteria in soil: influence of clay minerals and pH.

Fungi (Rhizopus stolonifer, Trichoderma viride, Fusarium oxysporum f. sp. conglutinans, Cunninghamella echinulata, and several species of Aspergillus and Penicillium) tolerated higher concentrations of cadmium (Cd) when grown in soil than when grown on laboratory media, indicating that soil mitigated the toxic effects of Cd. In soil amended with clay minerals, montmorillonite provided partial or total protection against fungistatic effects of Cd, whereas additions of kaolinite provided little or no protection. Growth rates of Aspergillus niger were inhibited to a greater extent by 100 or 250 mug of Cd per g in soil adjusted to pH 7.2 than in the same soil at its natural pH of 5.1. However, there were no differences in the growth rates of Aspergillus fischeri with 100 or 250 mug of Cd per g in the same soil, whether at pH 5.1 or adjusted to pH 7.2. Growth of A. niger and A. fischeri in a soil contaminated with a low concentration of Cd (i.e., 28 mug/g), obtained from a site near a Japanese smelter, did not differ significantly from growth in a soil collected some distance away and containing 4 mug of Cd per g. Growth of A. niger in sterile soil amended with 100 mug of Cd per g and inoculated with Bacillus cereus or Agrobacterium tumefaciens was reduced to a greater extent than in the same soil containing 100 mug of Cd per g but no bacteria. The inhibitory effects of Agrobacterium radiobacter to A. niger were slightly reduced in the presence of 100 mug of Cd per g, whereas the inhibitory effects of Serratia marcescens were enhanced.

Antibiosis

Monoclonal antibodies to Gliocladium roseum, a potential biological control fungus of sap-staining fungi in wood.

Immunological probes were developed to discriminate between a potential biological control fungus and sap-staining fungi present in wood. This paper describes the production of monoclonal antibodies to isolated cell wall fragments of the biological control fungus Gliocladium roseum. Two monoclonals, designated 6A5 and 3F12, were characterized. Their specificity was assessed by ELISA, by immunogold silver staining light microscopy, by immunogold electron microscopy, and by immunoblotting. Monoclonal 6A5 specifically recognized G. roseum and closely related species and did not react with any of 21 sap-staining fungi tested. Monoclonal 3F12 recognized most of the biological control fungi tested and also showed reactivity with two of the 21 sap-staining fungi. Both monoclonals appeared to recognize carbohydrate epitopes of the cell wall in G. roseum. Although the antibodies were produced against the cell wall of fungus grown in liquid culture, they also detected specific fungi in wood and, therefore, can be used for studies of wood colonization by fungi and for investigations of the interactions between different fungi growing on wood.

Antibodies, Fungal

Phytohormones in fungi: inter-kingdom modulators or fungal self-controlling elements?

SUMMARYLeveraging data from innovative experimental approaches, omics technologies, and bioinformatics, we offer new insights into how fungi communicate with and perceive their environment to achieve ecological success. By integrating comparative data from both the fungal and plant kingdoms, we critically reassessed the evolutionary, biochemical, and functional landscape of phytohormones in fungi, challenging the conventional notion that these molecules serve exclusively as plant regulators or as means of communication with them. Our analysis demonstrates that fungi not only synthesize a diverse array of phytohormones-including auxins, cytokinins, gibberellins, abscisic acid, ethylene, brassinosteroids, salicylic acid, and oxylipins-but also possess hormone-sensing and signal transduction mechanisms architecturally distinct from those of plants. Employing genomics, phylogenetics, and structural analyses, the review uncovers that many hormone biosynthetic and sensing pathways in fungi are evolutionarily ancient, sometimes predating their roles in plant-fungus interactions, and that some pathways show convergence rather than direct gene homology. Fungal phytohormones regulate development, growth, and metabolism, thereby playing key functions in their ecological context. The review emphasizes that, while biosynthetic pathways tend to be highly conserved, perception and signaling mechanisms in fungi are more varied and often remain poorly understood. We conclude that fungi have an intrinsic and autonomous hormonal physiology that underpins their ecological adaptability and success. Collectively, this analysis reframes fungal biology, highlighting the need for deeper investigation into the signaling and regulatory roles of phytohormones in fungi beyond their interactions with plants.

cell signaling

Pneumocystis carinii and specific fungi have a common epitope, identified by a monoclonal antibody.

Because Pneumocystis carinii may be related to fungi, we evaluated the reactivities of monoclonal antibodies raised against P. carinii with a variety of fungi. Fifty-two fungi and six protozoa were evaluated by immunofluorescence. One of three monoclonal antibodies (MAbs) tested (MAb 7D7) reacted with 15 fungi but no protozoa. Saccharomyces cerevisiae showed the strongest reactivity by immunofluorescence. The reactive antigen was characterized for four fungi by the immunoblot technique. In all cases the antigen that was reactive with MAb 7D7 was larger than the P. carinii antigens that reacted with 7D7. In further studies with P. carinii, Aspergillus species, and S. cerevisiae, we found that MAb 7D7 reacted with a carbohydrate component in all organisms. The presence of an epitope that is common to P. carinii and a number of fungi further supports the fungal nature of P. carinii.

Antibodies, Monoclonal

The a and b loci of Ustilago maydis hybridize with DNA sequences from other smut fungi.

The smut fungi are obligately parasitic during the sexual phase of their life cycle, and the mating-type genes of these fungi play key roles in both sexual development and pathogenicity. Among species of smut fungi it is common to find a bipolar mating system in which one locus with two alternate alleles is believed to control cell fusion and establishment of the infectious cell type. Alternatively, several species have a tetrapolar mating system in which two different genetic loci, one of which has multiple alleles, control fusion and subsequent development of the infection hyphae. Cloned sequences from the a and b mating-type loci of the tetrapolar smut fungus Ustilago maydis were used as hybridization probes to DNAs from 23 different fungal strains, including smut fungi with both tetrapolar and bipolar mating systems. In general, all of the smut fungi hybridized with the mating-type genes from U. maydis, suggesting conservation of the sequences involved in mating interactions. A selection of DNAs from other ascomycete and basidiomycete fungi failed to hybridize with the U. maydis mating-type sequences. Exceptions to this finding include hybridization of DNA from the a1 idiomorph of U. maydis to DNA from one strain of U. violacea and hybridization of both a idiomorphs to DNA from Saccharomyces cerevisiae.

Genes, Fungal

Growth of fungi in broiler houses.

The growth of fungi in broiler houses with and without histories of problems of unknown etiology or of mycotoxicoses was studied. Fungal growth data were obtained by the strip bait method and results expressed as frequency and relative density. The frequency and relative density of fungal growth of several species were higher in problem houses than in those without problems. In problem houses many known toxic fungi and several fungi of unknown toxicity were found growing, increasing in density and frequency during the rearing period. Houses without problems (control houses) were dominated throughout the rearing period by the growth of Scopulariopsis brevicaulis. This fungus grew infrequently and in low relative density in problem houses. There was no correlation between species composition and litter removal, pH, and moisture in problem and control houses. Fungi did not grow in inside feed hoppers or in dust on rafters in the broiler houses. One thermotolerant and two thermophilic species of fungi were found growing in outside feed bins. Three generalized fungal growth patterns in litter are described and theoretical consideration of environmental factors on these patterns are discussed.

Animals

Drug resistance in human pathogenic fungi.

Since the therapy of the mycoses, particularly the systemic mycoses, is relatively long-term in nature, emergence of resistance to antifungal drugs during the treatment of period would be of considerable clinical importance. However, most reports of resistance to antifungal agents among human pathogenic fungi indicate that naturally-occurring resistance is very rare, and that the induction of resistant mutants or variants is much more difficult to achieve in vitro and in vivo than with bacteria. As a matter of fact, amphotericin B and some other classic antifungals have not as yet posed a broadly significant problem relative to drug resistance despite their widespread and frequent use. Fungal resistance has thus received little attention, in contrast to the critical importance of bacterial resistance frequently caused by a variety of antibacterial chemotherapeutic agents, until a single exception to this generalization arose with the advent of flucytosine. This new development has aroused great interest in the problem of fungal resistance among the scientists involved with medical mycology. It is generally believed that fungi, like bacteria, are intrinsically capable of developing resistance to antifungal agents. As illustrated by flucytosine, inherently resistant mutants to antifungals occur within sensitive strains of human pathogenic fungi with significant frequency. Given the relatively high degree of such primary resistance, these mutants should develop secondary resistance during therapy, thus resulting in considerable limitations in the clinical usefulness of the antifungals. Virtually, all unsuccessful cases of mycoses treated with some of the recently exploited antifungal drugs, albeit scarce to date, would obviously be attributable to the occurrence of secondary resistance. The exploitation of new antifungal drugs thus requires investigations of their resistance as one of the most important research projects to be undertaken before receiving approval for use on humans. This paper reviews from various aspects the literature on resistance to various classic and novel antifungal agents among human pathogenic fungi. The resistance of some nonpathogenic fungi to these agents will also be described from genetic and biochemical points of view.

Antifungal Agents

Role of opportunistic fungi in ocular infections in Nigeria.

The importance of opportunistic fungal pathogens in causing ocular infections is emphasized. A study was conducted over a period of 4 years (1974--1977) to investigate the role of opportunistic fungi in causing mycotic keratitis and to elucidate certain aspects of epidemiology of this disease in Nigeria. Fifty-nine cases of corneal ulcers of suspected mycotic etiology were investigated. Fungal etiology was confirmed in 42 of these cases. The predominant etiological agent was Fusarium solani in 14 cases (33.33%) followed by Penicillium citrinum in 8 cases (19.04%) and Aspergillus fumigatus in 5 cases (11.90%). The yeasts were responsible for only 3 cases (7.14%) i.e. one each caused by Candida albicans, C. parapsilosis and C. guilliermondii. Among the remaining 12 cases, one was caused by F. moniliforme, 3 by A. flavus, 2 each by A. niger, Penicillium expansum and Penicillium sp., and one each by Cladosporium cladosporioides and Cladosporium sp. The clinical features of the cases are briefly described. The incidence of mycotic keratitis in relation to sex, age, occupation, trauma and other factors has been analysed. Corneal trauma appeared to be an important predisposing factor as 27 (67.28%) of the patients gave a history of injuries to the eye. Notably, a large number of patients were farmers and trauma was most often from palm tree leaf, thorn, kernel or other plant objects. Topical application of corticosteroids or broad spectrum antibiotics did not seem to play an important role in the etiology of keratomycosis. Cases were recorded throughout the year although the number of cases was higher in the months of March--May, and November--December than that during the rest of the year. The isolates of the causative agents were studied in detail for their morphological and cultural characters. The isolates of F. solani grew well at 37 degrees C and survived at 40 degrees C for more than 3 weeks. In vitro drug sensitivity tests indicated good antifungal activity of pimaricin and econazole for F. solani, clotrimazole and econazole for Aspergillus fumigatus. A. flavus and Penicillium citrinum, and 5-fluorocytosine for Candida spp. Investigations on the incidence of fungi in normal healthy eyes of 450 persons comprising 204 adults and 246 children yielded 204 isolates belonging to 21 genera of fungi. Cladosporium was most frequent (12.88%) followed by Penicillium (10.22%) and Aspergillus (6.66%). Another important fungus was Fusarium represented by 10 isolates, viz. 4 of F. solani, 2 of F. moniliforme, 1 of F. exysporum, and 3 of Fusarium sp. The yeasts were represented by two isolates each of Candida tropicalis, C. pseudotropicalis, C. krusei, Trichosporon sp and Cryptococcus albidus, and one of Candida guilliermondii. Successive culturing of fungi from normal eyes in a small group indicated that fungi occur in the outer eye generally as transients. The epidemiology of mycotic keratitis has been discussed in relation to the present findings and in comparison with observations of other investigators.

Adolescent

Isolation and properties of fungi that lyse blue-green algae.

Of 70 pure microbial cultures isolated from aquatic habitats, soil, and air according to the ability to lyse live blue-green algae, 62 were fungi representing the genera Acremonium, Emericellopsis, and Verticillium. Algal-lysing fungi were isolated from all habitat types sampled. The remaining isolates comprised four bacteria and four streptomycetes. All isolates lysed Anabaena flos-aquae and, in most cases, several other filamentous and unicellular blue-green algae. The fungi generally showed greater activity than most other isolates towards a wider range of susceptible algae, including green algae in some cases. Acremonium and Emericellopsis isolates, but not Verticillium, also inhibited the growth of blue-green algae and gram-positive bacteria, but did not lyse the latter. Lysis of blue green algae by Acremonium and Emericellopsis spp. was associated with the formation of diffusible heat-stable extracellular factors which, evidence suggests, could be cephalosporin antibiotic(s). Blue-green algae were also lysed by pure cephalosporin C. The frequent isolation of lytic fungi from algal habitats suggests a possible natural algal-destroying role for such fungi, which might be exploitable for algal bloom control.

Air Microbiology

Detection of fungi in blood cultures.

In a retrospective study covering the period January 1972 to June 1974, recovery rates of bacteria and of fungi were generally equivalent with tryptic soy broth, Thiol, thioglycolate, and Columbia broth media (all under vacuum with carbon dioxide and sodium polyanetholesulfonate). An additional biphasic medium consisting of brain heart infusion broth and a brain heart infusion agar slant, which was inoculated only where fungal sepsis was suspected clinically, yielded significantly higher recovery rates of fungi. There were 29 instances of cultures with fungi in both the biphasic and broth media, 80 instances of cultures with fungi only in the biphasic medium, and no instances of fungi only in the broth media. The isolates were as follows: Candida albicans, 74; C. parapsilosis, 20; C. tropicalis, 16; Torulopsis glabrata, 18; Torulopsis sp., 1; Cryptococcus neoformans, 12; C. laurentii, 2; and Histoplasma capsulatum, 16. Despite routine subcultures of the broth media to chocolate blood agar within 24 h of inoculation and after 5 days of incubation, detection of fungemia was significantly improved by the use of a biphasic medium.

Bacteria