Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FUNGUS DISEASE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources
PubMed2005

Impact of disinfecting nesting boards on chalkbrood control in the alfalfa leafcutting bee.

The alfalfa leafcutting bee, Megachile rotundata (F.), is a solitary, cavity-nesting bee that has been managed in large numbers to pollinate alfalfa, Medicago spp., seed crops since the 1960s. Propagation of these bees from 1 yr to the next has been seriously hampered by chalkbrood, a larval disease caused by the fungus Ascosphaera aggregata Skou. In the United States, attempts to control the disease have been fairly unsuccessful, but include removing nests from the nesting boards and then disinfecting the boards with heat treatments or a fumigant. The problem is that many boards are made of polystyrene (so heat cannot be used), and very few fumigants are registered for this use. In this study, ozone was tested as a fumigant and compared with heat treatments and methyl bromide fumigation. Ozone was found to be inadequate for killing A. aggregata spores and for reducing chalkbrood levels in the field. Methyl bromide and heat treatments did greatly reduce spore viability in the boards, but did not reduce chalkbrood levels in the field. Surprisingly, larvae in new nesting boards (boards free of contamination) and chalkbrood infection levels were similar to those from nests in contaminated, used boards. Disinfecting nesting boards may be necessary for controlling chalkbrood, but the results reported here indicate that it is not sufficient in and of itself. Some other source of spores was present in the field that was greater than the effect of contamination from the boards, but the source still needs to be determined.

Animals↗
PubMedDate not supplied

Classification of the guava wilt fungus Myxosporium psidii, the palm pathogen Gliocladium vermoesenii and the persimmon wilt fungus Acremonium diospyri in Nalanthamala.

Psidium guajava wilt is known from South Africa, Malaysia and Taiwan. The fungus causing this disease, Myxosporium psidii, forms dry chains of conidia on surfaces of pseudoparenchymatous sporodochia, which develop in blisters on bark. Similar sporodochia are characteristic of Nalanthamala madreeya, the type species of Nalanthamala. Nalanthamala, therefore, is the appropriate anamorph genus for Myxosporium psidii, while Myxosporium is a nomen nudum (based on M. croceum). For M. psidii the combination Nalanthamala psidii is proposed. Nalanthamala psidii, the palm pathogen Gliocladium (Penicillium) vermoesenii, another undescribed anamorphic species from palm, two species of Rubrinectria and the persimmon pathogen Acremonium diospyri are monophyletic and belong to the Nectriaceae (Hypocreales) based on partial nuclear large subunit ribosomal DNA (LSU rDNA) analyses. Rubrinectria, therefore, is the teleomorph of Nalanthamala, in which the anamorphs are classified as N. vermoesenii, N. diospyri or Nalanthamala sp. Nalanthamala squamicola, the only other Nalanthamala species, has affinities with the Bionectriaceae and is excluded from this group. Rubrinectria/Nalanthamala species form dimorphic conidiophores and conidia in culture. Fusiform, cylindrical, or allantoid conidia arise in colorless liquid heads on acremonium-like conidiophores; ovoidal conidia with somewhat truncated ends arise in long, persistent, dry chains on penicillate conidiophores. No penicillate but irregularly branched conidiophores were observed in N. diospyri. Conidia of N. psidii that are held in chains are shorter than those of N. madreeya, of which no living material is available. Nalanthamala psidii and N. diospyri are pathogenic specifically to their hosts. They form pale yellow to pale orange or brownish orange colonies, respectively, and more or less white conidial masses. Most strains of Rubrinectria sp., Nalanthamala sp. and N. vermoesenii originate from palm hosts, form mostly greenish or olive-brown colonies and white-to-salmon conidial masses. They form a monophyletic clade to which Nalanthamala psidii and N. diospyri are related based on analyses of the internal transcribed spacer regions and 5.8S rDNA (ITS rDNA), LSU rDNA, and partial beta-tubulin gene. Few polymorphic sites in the ITS rDNA and beta-tubulin gene indicate that Nalanthamala psidii comprises two lineages, one of which has been detected only in South Africa.

Acremonium↗
PubMed2006

[Serological method of rapid identification of antibodies against fungi of Candida genus].

Technology of preparation of antigenic erythrocytes diagnosticum for detection of antibodies against fungi of Candida genus in humans blood is presented. Preparation is used in reaction of passive haemagglutination destined for serological investigation of candidosis. Erythrocytes of sheep treated with formalin and tannin acid were used for preparation of diagnosticum. In the capacity of sensitin were water-soluble antigens, received by multiple (5-6) freezing-wash cleaning of Candida fungi cultures. Optimal sensitizing dose (8 mkg/ml) was defined experimentally. Investigation of blood serum of healthy people has shown, that medium titer of anti-candidosis antibodies is 38.0+/-7.9. Obtained results testify, that antigenic diagnosticum could be successfully used for serological diagnosis of diseases caused by fungus of Candida genus.

Animals↗
PubMed2005

Influence of temperature and nutritional requirements for mycelial growth of Eutypa lata, a vineyard pathogenic fungus.

Eutypa dieback (dying arm disease, eutypiosis) is a very devastating disease in many grape-producing areas around the world. This vascular disease is induced by the ascomycete Eutypa lata Pers. Fr. Tul & C. Tul. invading the trunk by pruning wounds. The environmental factors and the nutritional requirements regulating fungus development are yet poorly known. This work shows that the isolated strain of E. lata was able to grow in a large temperature range (2-30 degrees C). However, a higher temperature (35 degrees C) presented inhibitory effects on mycelial growth. E. lata was able to use various osidic molecules (C5, C6, C12, C18, C24, and starch); showing thus a large adaptation to the carbon source supplied. As nitrogen source, it used salts and numerous natural amino acids. A significant result was obtained with cysteine presenting obvious antifungal properties. This effect can further be used with the aim of setting up a curative treatment of the disease.

Ascomycota↗
PubMed2005

The endophytic fungus Piriformospora indica reprograms barley to salt-stress tolerance, disease resistance, and higher yield.

Disease resistance strategies are powerful approaches to sustainable agriculture because they reduce chemical input into the environment. Recently, Piriformospora indica, a plant-root-colonizing basidiomycete fungus, has been discovered in the Indian Thar desert and was shown to provide strong growth-promoting activity during its symbiosis with a broad spectrum of plants. Here, we report on the potential of P. indica to induce resistance to fungal diseases and tolerance to salt stress in the monocotyledonous plant barley. The beneficial effect on the defense status is detected in distal leaves, demonstrating a systemic induction of resistance by a root-endophytic fungus. The systemically altered "defense readiness" is associated with an elevated antioxidative capacity due to an activation of the glutathione-ascorbate cycle and results in an overall increase in grain yield. Because P. indica can be easily propagated in the absence of a host plant, we conclude that the fungus could be exploited to increase disease resistance and yield in crop plants.

Ascorbic Acid↗
PubMed1992

Detection of cellular immunity with the soluble antigen of the fungus Sporothrix schenckii in the systemic form of the disease.

Sporothrix schenckii is the etiologic agent of sporotrichosis, a mycosis of world-wide distribution more commonly occurring in tropical regions. The immunological mechanisms involved in the prevention and control of sporotrichosis are not fully understood but apparently include both the humoral and cellular responses. In the present investigation, cellular immunity was evaluated by in vivo and in vitro tests in mice infected with yeast-like forms of S. schenckii. The disease developed systemically and cellular immunity was evaluated for a period of 10 weeks. The soluble antigen utilized in the tests was prepared from yeast form of the fungus through the sonication (20 min: 10 sonications at 50 W at 2-min intervals). Delayed hypersensitivity and lymphocyte transformation tests showed that the cellular immune response was depressed between the 4th and 6th week of infection when the animals were challenged with the soluble fungal antigen. This depression frequently indicates worsening of the disease, with greater involvement of the host. This is a promising field of research for a better understanding of the pathogeny of this mycosis.

Animals↗
PubMed1994

Molecular genetics of Aspergillus pathogenicity.

Aspergillus fumigatus is the most frequent cause of Invasive Pulmonary Aspergillosis (IPA), a life-threatening disease of immunosuppressed patients. In addition to a number of general physiological attributes of this fungus, it has been suggested that extracellular elastase and toxins might facilitate its growth in lung tissue. We have investigated the roles of two extracellular proteins, an alkaline protease with elastase activity (AFAlp), and the ribotoxin restrictocin in murine models of IPA. Gene disruption was used to create stable null mutant strains of the fungus lacking one or other protein, and their virulence and histopathological features were compared with an isogenic parental strain in steroid-treated and neutropenic mice. We have been unable to demonstrate any significant differences between the three strains, which shows that, considered independently, these proteins are not important virulence determinants. We are also interested in identifying fungal-specific gene products involved in general metabolism and which are required for growth in the lung, because these could represent new targets for antifungal drugs. For this work a model of murine IPA involving Aspergillus nidulans was established, to take advantage of the many well characterised mutations affecting metabolic pathways. Pathogenicity tests with strains carrying one of two auxotrophic mutations, lysA2 and pabaA1, have shown while lysine biosynthesis is not essential for the fungus to cause pulmonary disease, biosynthesis of p-aminobenzoic acid is essential. We are now in the process of cloning the A. fumigatus pabaA homologue to determine its function and whether this gene is required for growth of the clinically important species in the lung.

4-Aminobenzoic Acid↗
PubMed2002

Animal models of allergic bronchopulmonary aspergillosis.

Among the allergic fungi, Aspergillus fumigatus, a saprophytic mold, distributed widely in the environment is a frequently recognized etiologic agent in a number of allergic conditions. Among the different allergic diseases caused by this fungus, allergic bronchopulmonary aspergillosis (ABPA) is by far the most significant one. The immunopathogenesis of this disease is not fully understood. Although several immunomodulatory treatments are available for allergic disease, none of them are applicable or relevant or useful in fungal induced allergy. It is essential to understand the pathogenesis of the disease including the antigen induced immunoregulation and the resulting factors, such as cytokine, chemokines, pathways activating factors, inflammatory and airway remodeling factors need to be understood for intervening with appropriate treatment. Animal models are essential in understanding these features of the disease. Several models of allergic aspergillosis have been developed in recent years in various animals. However, murine models have been studied more carefully and extensively. The exposure to antigen in mice leads to allergy very similar to ABPA with high IgE, elevated peripheral blood and lung eosinophils, pulmonary inflammation, and airway hyperreactivity. The role of various cytokines and chemokines and their receptors were also studied. In addition, immunotherapy and vaccination have been attempted in recent years using the murine model of ABPA. This review covers the murine model of Aspergillus induced allergy and asthma and presented critically our current understanding of the subject and the potential application of such a model in future for developing treatment modalities.

Animals↗
PubMed2003

Plant species descriptions show signs of disease.

It is well known that diseases can greatly influence the morphology of plants, but often the incidence of disease is either too rare or the symptoms too obvious for the 'abnormalities' to cause confusion in systematics. However, we have recently come across several misinterpretations of disease-induced traits that may have been perpetuated into modern species inventories. Anther-smut disease (caused by the fungus Microbotryum violaceum) is common in many members of the Caryophyllaceae and related plant families. This disease causes anthers of infected plants to be filled with dark-violet fungal spores rather than pollen. Otherwise, their vegetative morphology is within the normal range of healthy plants. Here, we present the results of a herbarium survey showing that a number of type specimens (on which the species name and original description are based) in the genus Silene from Asia are diseased with anther smut. The primary visible disease symptom, namely the dark-violet anthers, is incorporated into the original species descriptions and some of these descriptions have persisted unchanged into modern floras. This raises the question of whether diseased type specimens have erroneously been given unique species names.

Basidiomycota↗
PubMed2004

A reovirus of the fungus Cryphonectria parasitica that is infectious as particles and related to the coltivirus genus of animal pathogens.

RNA viruses of filamentous fungi fall into two broad categories, those that contain double-stranded RNA (dsRNA) genomes in rigid particles and those that are more closely related to positive-sense, single-stranded RNA viruses with dsRNA replicative intermediates found within lipid vesicles. Effective infectivity systems have been described for the latter, using RNA transcripts, but not for the former. We report the characterization of a reovirus from Cryphonectria parasitica, the filamentous fungus that causes chestnut blight disease. The virus substantially reduces the virulence of the fungus and results in dramatically altered colony morphology, as well as changes in other associated fungal traits, relative to the virus-free isogenic strain. Virus particles from infected mycelium contained 11 segments of dsRNA and showed characteristics typical of the family Reoviridae. Sequences of the largest three segments revealed that the virus is closely related to the Coltivirus genus of animal pathogens, which includes the human pathogen Colorado tick fever virus. The introduction of purified virus particles into protoplasts from virus-free isolates of the fungus resulted in a newly infected mycelium with the same morphology and virus composition as the original virus-infected isolate. This represents the completion of Koch's postulates for a true dsRNA virus from a filamentous fungus and the description of a definitive fungal member of the family Reoviridae.

Ascomycota↗
PubMed1979

An intracavitary fungus ball composed of syncephalastrum.

A case of a pulmonary intracavitary fungus ball composed of Syncephalastrum sp., a member of the class Zygomycetes not previously reported in association with human disease, is presented. The fungus was cultured preoperatively from bronchial secretions as well as from the fungal mass from the resected lung. This fungus appeared to behave in a saprophytic manner similar to that of the more common Aspergillus fungus ball.

Fungi↗
PubMed1995

Summer-type hypersensitivity pneumonitis.

Summer-type hypersensitivity pneumonitis (SHP), the most prevalent type of HP in Japan, is caused by seasonal mold contamination in the home environment. The causative agent of the disease is Trichosporon cutaneum. The fungus grows in warm, moldy, decaying organic matter, and scatters in the air from the colonizing places. The inhaled fungi sensitize susceptible patients intratracheally and induce the disease. Glucuronoxylomannan of the fungus has a potent antigenicity that causes granulomatous alveolitis. Assay of anti-T. cutaneum antibody is very useful to establish the diagnosis of the disease because the antibody activity is virtually positive in all cases of the disease. Elimination of T. cutaneum from the colonizing places prevents recrudescence. SHP, a new form of HP, had been considered to be peculiar to Japan, but the first case of SHP outside Japan was identified in Korea last year. Soon it will be recognized in many countries of temperate and tropical clime.

Alveolitis, Extrinsic Allergic↗