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Sample records for growth ability conidia

  1. Ecological study of Paracoccidioides brasiliensis in soil: growth ability, conidia production and molecular detection

    PubMed Central

    Terçarioli, Gisela Ramos; Bagagli, Eduardo; Reis, Gabriela Martins; Theodoro, Raquel Cordeiro; Bosco, Sandra De Moraes Gimenes; Macoris, Severino Assis da Graça; Richini-Pereira, Virgínia Bodelão

    2007-01-01

    Background Paracoccidioides brasiliensis ecology is not completely understood, although several pieces of evidence point to the soil as its most probable habitat. The present study aimed to investigate the fungal growth, conidia production and molecular pathogen detection in different soil conditions. Methods Soils samples of clayey, sandy and medium textures were collected from ground surface and the interior of armadillo burrows in a hyperendemic area of Paracoccidioidomycosis. P. brasiliensis was inoculated in soil with controlled humidity and in culture medium containing soil extracts. The molecular detection was carried out by Nested PCR, using panfungal and species specific primers from the ITS-5.8S rDNA region. Results The soil texture does not affect fungus development and the growth is more abundant on/in soil saturated with water. Some soil samples inhibited the development of P. brasiliensis, especially those that contain high values of Exchangeable Aluminum (H+Al) in their composition. Some isolates produced a large number of conidia, mainly in soil-extract agar medium. The molecular detection was positive only in samples collected from armadillo burrows, both in sandy and clayey soil. Conclusion P. brasiliensis may grow and produce the infectious conidia in sandy and clayey soil, containing high water content, mainly in wild animal burrows, but without high values of H+Al. PMID:17953742

  2. Filter Paper Degrading Ability of a Trichoderma Strain With Multinucleate Conidia

    NASA Astrophysics Data System (ADS)

    Toyama, Hideo; Yano, Makiko; Hotta, Takeshi; Toyama, Nobuo

    The multinucleate conidia were produced from the green mature conidia of Trichoderma reesei Rut C-30 strain by colchicine treatment. The strain with higher Filter paper degrading ability was selected among those conidia using a double layer selection medium. The selected strain, JS-2 was able to collapse the filter paper within 15 min but the original strain took 25 min to collapse it completely. Moreover, the amount of reducing sugar in the L-type glass tube of the strain, JS-2, was greater than that of the original strain. The Avicel, CMC-Na, and Salicin hydrolyzing activity of the strain, JS-2, increased 2.1 times, 1.2 times, and 3.6 times higher than that of the original strain.

  3. Boric Acid Inhibition of Trichophyton rubrum Growth and Conidia Formation.

    PubMed

    Schmidt, Martin

    2017-04-08

    Trichophyton rubrum is a common human dermatophyte that is the causative agent of 80-93% of fungal infections of the skin and nails. While dermatophyte infections in healthy people are easily treatable with over-the-counter medications, such infections pose a higher risk for patients with compromised immune function and impaired regenerative potential. The efficacy of boric acid (BA) for the treatment of vaginal yeast infections prompted an investigation of the effect of BA on growth and morphology of T. rubrum. This is of particular interest since BA facilitates wound healing, raising the possibility that treating athlete's foot with BA, either alone or in combination with other antifungal drugs, would combine the benefits of antimicrobial activity and tissue regeneration to accelerate healing of infected skin. The data presented here show that BA represses T. rubrum growth at a concentration reported to be beneficial for host tissue regeneration. Oxygen exposure increases BA toxicity, and mycelia growing under BA stress avoid colonizing the surface of the growth surface, which leads to a suppression of aerial mycelium growth and surface conidia formation. BA penetrates into solid agar matrices, but the relative lack of oxygen below the substrate surface limits the effectiveness of BA in suppressing growth of embedded T. rubrum cells.

  4. Growth under visible light increases conidia and mucilage production and tolerance to UV-B radiation in the plant pathogenic fungus Colletotrichum acutatum.

    PubMed

    de Menezes, Henrique D; Massola, Nelson S; Flint, Stephan D; Silva, Geraldo J; Bachmann, Luciano; Rangel, Drauzio E N; Braga, Gilberto U L

    2015-01-01

    Light conditions can influence fungal development. Some spectral wavebands can induce conidial production, whereas others can kill the conidia, reducing the population size and limiting dispersal. The plant pathogenic fungus Colletotrichum acutatum causes anthracnose in several crops. During the asexual stage on the host plant, Colletototrichum produces acervuli with abundant mucilage-embedded conidia. These conidia are responsible for fungal dispersal and host infection. This study examined the effect of visible light during C. acutatum growth on the production of conidia and mucilage and also on the UV tolerance of these conidia. Conidial tolerance to an environmentally realistic UV irradiance was determined both in conidia surrounded by mucilage on sporulating colonies and in conidial suspension. Exposures to visible light during fungal growth increased production of conidia and mucilage as well as conidial tolerance to UV. Colonies exposed to light produced 1.7 times more conidia than colonies grown in continuous darkness. The UV tolerances of conidia produced under light were at least two times higher than conidia produced in the dark. Conidia embedded in the mucilage on sporulating colonies were more tolerant of UV than conidia in suspension that were washed free of mucilage. Conidial tolerance to UV radiation varied among five selected isolates.

  5. Conidia immobilization of T-DNA inserted Trichoderma atroviride mutant AMT-28 with dichlorvos degradation ability and exploration of biodegradation mechanism.

    PubMed

    Sun, Wenliang; Chen, Yunpeng; Liu, Lixing; Tang, Jun; Chen, Jie; Liu, Peng

    2010-12-01

    An immobilizing conidia approach was used to study the degradation ability of dichlorvos in Trichoderma atroviride T-DNA insertional mutant AMT-28. Beads with 10(7) immobilized conidia per 100 mL of Na-alginate solution exhibited the highest degradation abilities. The immobilized conidia showed enhanced degradation abilities compared with immobilized or freely suspended mycelia. The immobilized cells kept good storage capacity and reusability. Dichlorvos was confirmed to be completely removed by mycelia of AMT-28 within 7 days using HPLC analysis. The dichlorvos degradation rates in auxotrophic Burk media varied and were significantly affected by nitrogen sources. There was no detectable biosorption and the removal of dichlorvos in AMT-28 was primarily attributed to a kind of Biomineralization process.

  6. Algorithm-based design of synthetic growth media stimulating virulence properties of Metarhizium anisopliae conidia.

    PubMed

    Hutwimmer, S; Wagner, S; Affenzeller, M; Burgstaller, W; Strasser, H

    2008-12-01

    Synthetic media should be designed for the production of Metarhizium anisopliae conidia with improved virulence properties. A genetic algorithm (GA), demonstrated to be suitable for the design of media for spore mass production (Hutwimmer et al. 2008), was utilized for a multi-objective medium design to improve conidia yield and three proposed virulence properties of conidia: C : N ratio, germination speed and amount of spore-bound Pr1 protease. After five iterative optimizations, 52 media were improved over Sabouraud dextrose agar (SDA). Four media exhibited medium performances (a factor derived from the four single optimization variables) of around 0.7; cf. SDA = 0.532; media with enhanced properties were reached for each single optimization variable; Bioassays against Tenebrio larvae indicated also a slight improvement in virulence of conidia from designed media. A degenerated phenotype of the same strain did not exhibit differences in colony appearance, spore characteristics and virulence if grown on designed media. The application of a problem-oriented GA is a practical and rapid method to design media for multi-objective purposes. The applicability of a GA for multi-objective medium design was demonstrated for the cultivation of anamorphic fungi on solid media.

  7. Aspergillus fumigatus germ tube growth and not conidia ingestion induces expression of inflammatory mediator genes in the human lung epithelial cell line A549.

    PubMed

    Bellanger, Anne-Pauline; Millon, Laurence; Khoufache, Khaled; Rivollet, Danièle; Bièche, Ivan; Laurendeau, Ingrid; Vidaud, Michel; Botterel, Françoise; Bretagne, Stéphane

    2009-02-01

    Inhalation of conidia is the main cause of invasive pulmonary aspergillosis (IPA) and the respiratory epithelium is the first line of defence. To explore the triggering factor for the inflammatory response to Aspergillus fumigatus, the species mainly responsible for IPA, this study analysed the differential expression of three inflammatory genes in A549 cells after challenge with live and killed conidia. The influence of steroids, one of the main risk factors for developing IPA, was also investigated. Quantification of mRNAs of the inflammatory mediator genes encoding interleukin (IL)-8, tumour necrosis factor (TNF)-alpha and granulocyte-monocyte colony-stimulating factor (GM-CSF) was carried out using real-time PCR. Ingestion rates were studied for the conidia of A. fumigatus and Penicillium chrysogenum using a fluorescence brightener. Similar results were obtained for both species, with ingestion rates ranging from 35 to 40 %. Exposure of A549 cells to live A. fumigatus conidia only induced a four- to fivefold increase in the mRNA levels of the three genes, starting 8 h after the initial contact. Both inactivation of live A. fumigatus conidia and treatment by dexamethasone (10(-7) M) prevented the overexpression of TNF-alpha, IL-8 and GM-CSF. Fungal growth, rather than conidia ingestion, appears to be the main stimulus for the production of inflammatory mediators by epithelial cells, and this production is inhibited by steroid therapy. These results underline the role that the epithelium plays in the innate response against IPA.

  8. The effect of selected allelochemicals on germination of conidia and blastospores and mycelial growth of the entomopathogenic fungus, Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes).

    PubMed

    Lacey, L A

    1998-01-01

    Selected allelochemicals that protect plants from invasion by plant pathogenic fungi were investigated for their activity against the entomopathogenic fungus, Paecilomyces fumosoroseus. The alkaloids tomatine, solanine, and camptothecin; the furanocoumarin, xanthotoxin; and the phenolic, tannic acid were tested for their effects on germination of conidia and blastospores and growth of mycelia. The LC50 values (corresponding to 50% inhibition of germination) for tomatine, solanine, camptothecin, xanthotoxin and tannic acid were 51.6, 95.9, 55.9, 83.0 and 72.8 mg/l respectively. When blastospores were placed on media containing a concentration of the individual allelochemicals that inhibit germination in approximately 50% of conidia, all but blastospores on tomatine had significantly less germination than did aerial conidia. Growth rates of mycelia were slowest in the camptothecin medium, followed by those of tomatine and xanthotoxin and were not significantly different from controls in the media containing solanine and tannic acid. A multitude of biotic and abiotic factors are responsible for specificity and degree of pathogenicity of entomopathogens. The effect of crop plant chemistry on the efficacy of entomopathogens should be quantified further in order to maximize their potential when used concomitantly with resistant plant varieties.

  9. Characterization of NpgA, a 4'-phosphopantetheinyl transferase of Aspergillus nidulans, and evidence of its involvement in fungal growth and formation of conidia and cleistothecia for development.

    PubMed

    Kim, Jung-Mi; Song, Ha-Yeon; Choi, Hyo-Jin; So, Kum-Kang; Kim, Dae-Hyuk; Chae, Keon-Sang; Han, Dong-Min; Jahng, Kwang-Yeop

    2015-01-01

    The null pigmentation mutant (npgA1) in Aspergillus nidulans results in a phenotype with colorless organs, decreased branching growth, delayed of asexual spore development, and aberrant cell wall structure. The npgA gene was isolated from A. nidulans to investigate these pleiomorphic phenomena of npgA1 mutant. Sequencing analysis of the complementing gene indicated that it contained a 4'-phosphopantetheinyl transferase (PPTase) superfamily domain. Enzymatic assay of the PPTase, encoded by the npgA gene, was implemented in vivo and in vitro. Loss-of-function of LYS5, which encoded a PPTase in Saccharomyces cerevisiae, was functionally complemented by NpgA, and Escherichia coli-derived NpgA revealed phosphopantetheinylation activity with the elaboration of 3'5'-ADP. Deletion of the npgA gene caused perfectly a lethal phenotype and the absence of asexual/sexual sporulation and secondary metabolites such as pigments in A. nidulans. However, a cross feeding effect with A. nidulans wild type allowed recovery from deletion defects, and phased-culture filtrate from the wild type were used to verify that the npgA gene was essential for formation of metabolites needed for development as well as growth. In addition, forced expression of npgA promoted the formation of conidia and cleistothecia as well as growth. These results indicate that the npgA gene is involved in the phosphopantetheinylation required for primary biological processes such as growth, asexual/sexual development, and the synthesis of secondary metabolites in A. nidulans.

  10. Killing of Paracoccidioides brasiliensis conidia by pulmonary macrophages and the effect of cytokines.

    PubMed

    Cano, L E; Arango, R; Salazar, M E; Brummer, E; Stevens, D A; Restrepo, A

    1992-01-01

    The ability of conidia, the infectious form of the dimorphic fungus Paracoccidioides brasiliensis, to be killed in vitro by murine pulmonary macrophages was studied. Mice were immunized by intravenous injection of killed conidia, which resulted in cellular immunity demonstrated by delayed type hypersensitivity in vivo and macrophage migration inhibition factor production in vitro. Resident pulmonary macrophages from non-immune mice were able to significantly kill the conidia (28%). Such macrophages treated with supernatants (cytokines) from antigen-stimulated immune mononuclears had a markedly enhanced ability to kill conidia (73%). These results show that activated pulmonary macrophages are potent killers of conidia of P. brasiliensis and that immune mononuclears play a role in activation of macrophages. Activated macrophages may be important for pulmonary defense against the initial stages of infection with this fungus.

  11. Nuclear staining of Paracoccidioides brasiliensis conidia.

    PubMed

    McEwen, J G; Restrepo, B I; Salazar, M E; Restrepo, A

    1987-10-01

    More than 80% of the conidia produced by two different isolates of Paracoccidioides brasiliensis, were found to be uninucleate; however, when they were incubated at 37 degrees C and began to transform into yeast cells, they became bi- or multi-nucleated, so that when most of the conidia had already transformed into yeast cells (72-96 h), there were at least four or five nuclei per cell in approximately 80% of the conidia examined.

  12. Physiological Response of Neurospora Conidia to Freezing in the Dehydrated, Hydrated, or Germinated State

    PubMed Central

    Leef, James L.; Mazur, Peter

    1978-01-01

    This study concerned the response to freezing of Neurospora crassa conidia in four different states: air-dry, hydrated in water, hydrated in Vogel medium lacking only sucrose, or hydrated in complete Vogel medium. All hydrated conidia were incubated in one of the above media for various times before freezing and were then washed and frozen in distilled water. Viability was estimated by three techniques, and the agreement among them was good. Hydration of air-dry conidia was found to be very rapid and, once hydrated, the conidia were much more sensitive to rapid freezing than they were before hydration. Rapidly cooled conidia survived freezing to a much higher extent when the warming rate was rapid than when it was slow; slowly cooled conidia showed little or no dependence on the warming rate. This sensitivity to rapid cooling and slow warming was attributed to the effects of intracellular ice. The sensitivity to freezing could be reversed by dehydrating the conidia in vacuo before freezing; thus, it was concluded that the presence or absence of water is the determining factor in the initial sensitivity due to freezing. In water, the sensitivity remained constant from 2 min to 15 days after hydration. Although conidia hydrated in growth medium lacking sucrose remained metabolically inactive, their sensitivity to rapid freezing decreased as a function of time in the medium before freezing. The reason for this decreased sensitivity is not understood. Conidia hydrated in complete growth medium (i.e., containing sucrose) became metabolically active and, after the initial sensitivity associated with hydration, became increasingly more sensitive to freezing as a function of their time in the medium. Drying itself was deleterious to metabolically active conidia, and those that survived dehydration did not exhibit a large absolute increase in resistance to subsequent freezing. The increase in sensitivity to freezing and to drying seems associated with the presence of

  13. Capillary electrophoresis of conidia from cultivated microscopic filamentous fungi.

    PubMed

    Horká, Marie; Růzicka, Filip; Kubesová, Anna; Holá, Veronika; Slais, Karel

    2009-05-15

    In immunocompromised people fungal agents are able to cause serious infections with high mortality rate. An early diagnosis can increase the chances of survival of the affected patients. Simultaneously, the fungi produce toxins and they are frequent cause of allergy. Currently, various methods are used for detection and identification of these pathogens. They use microscopic examination and growth characteristic of the fungi. New methods are based on the analysis of structural elements of the target microorganisms such as proteins, polysaccharides, glycoproteins, nucleic acids, etc. for the construction of antibodies, probes, and primers for detection. The above-mentioned methods are time-consuming and elaborate. Here hydrophobic conidia from the cultures of different strains of the filamentous fungi were focused and separated by capillary zone electrophoresis and capillary isoelectric focusing. The detection was optimized by dynamic modifying of conidia by the nonionogenic tenside on the basis of pyrenebutanoate. Down to 10 labeled conidia of the fungal strains were fluorometrically detected, and isoelectric points of conidia were determined. The observed isoelectric points were compared with those obtained from the separation of the cultured clinical samples, and they were found to be not host-specific.

  14. Germination of Aspergillus niger conidia is triggered by nitrogen compounds related to L-amino acids.

    PubMed

    Hayer, Kimran; Stratford, Malcolm; Archer, David B

    2014-10-01

    Conidial germination is fundamentally important to the growth and dissemination of most fungi. It has been previously shown (K. Hayer, M. Stratford, and D. B. Archer, Appl. Environ. Microbiol. 79:6924-6931, 2013, http://dx.doi.org/10.1128/AEM.02061-13), using sugar analogs, that germination is a 2-stage process involving triggering of germination and then nutrient uptake for hyphal outgrowth. In the present study, we tested this 2-stage germination process using a series of nitrogen-containing compounds for the ability to trigger the breaking of dormancy of Aspergillus niger conidia and then to support the formation of hyphae by acting as nitrogen sources. Triggering and germination were also compared between A. niger and Aspergillus nidulans using 2-deoxy-D-glucose (trigger), D-galactose (nontrigger in A. niger but trigger in A. nidulans), and an N source (required in A. niger but not in A. nidulans). Although most of the nitrogen compounds studied served as nitrogen sources for growth, only some nitrogen compounds could trigger germination of A. niger conidia, and all were related to L-amino acids. Using L-amino acid analogs without either the amine or the carboxylic acid group revealed that both the amine and carboxylic acid groups were essential for an L-amino acid to serve as a trigger molecule. Generally, conidia were able to sense and recognize nitrogen compounds that fitted into a specific size range. There was no evidence of uptake of either triggering or nontriggering compounds over the first 90 min of A. niger conidial germination, suggesting that the germination trigger sensors are not located within the spore.

  15. Kinetic studies on the aggregation of Aspergillus niger conidia.

    PubMed

    Grimm, L H; Kelly, S; Hengstler, J; Göbel, A; Krull, R; Hempel, D C

    2004-07-20

    Morphology has a crucial effect on productivity and the supply of substrate for cultures of filamentous fungi. However, cultivation parameters leading to the desired morphology are often chosen empirically as the mechanisms governing the processes involved are usually unknown. For coagulating microorganisms like Aspergillus niger the morphological development is considered to start with the aggregation of conidia right after inoculation. To elucidate the mechanism of this process, kinetic studies were carried out using an in-line particle size analyzer. Based on the data obtained from these experiments a model for conidial aggregation is proposed in this article. It consists of two separate aggregation steps. The first one takes place immediately after inoculation, but only leads to a small decrease of total particle concentration. Most suspended conidia aggregate after a second aggregation step triggered by germination and hyphal growth. Aggregation velocity of this second phase is linearly dependent on the particle growth rate.

  16. Proteomic profile of dormant Trichophyton Rubrum conidia

    PubMed Central

    Leng, Wenchuan; Liu, Tao; Li, Rui; Yang, Jian; Wei, Candong; Zhang, Wenliang; Jin, Qi

    2008-01-01

    Background Trichophyton rubrum is the most common dermatophyte causing fungal skin infections in humans. Asexual sporulation is an important means of propagation for T. rubrum, and conidia produced by this way are thought to be the primary cause of human infections. Despite their importance in pathogenesis, the conidia of T. rubrum remain understudied. We intend to intensively investigate the proteome of dormant T. rubrum conidia to characterize its molecular and cellular features and to enhance the development of novel therapeutic strategies. Results The proteome of T. rubrum conidia was analyzed by combining shotgun proteomics with sample prefractionation and multiple enzyme digestion. In total, 1026 proteins were identified. All identified proteins were compared to those in the NCBI non-redundant protein database, the eukaryotic orthologous groups database, and the gene ontology database to obtain functional annotation information. Functional classification revealed that the identified proteins covered nearly all major biological processes. Some proteins were spore specific and related to the survival and dispersal of T. rubrum conidia, and many proteins were important to conidial germination and response to environmental conditions. Conclusion Our results suggest that the proteome of T. rubrum conidia is considerably complex, and that the maintenance of conidial dormancy is an intricate and elaborate process. This data set provides the first global framework for the dormant T. rubrum conidia proteome and is a stepping stone on the way to further study of the molecular mechanisms of T. rubrum conidial germination and the maintenance of conidial dormancy. PMID:18578874

  17. Comparison of methodologies for conidia production by Alternaria alternata from citrus

    PubMed Central

    Carvalho, Daniel D. C.; Alves, Eduardo; Batista, Tereza R. S.; Camargos, Renato B.; Lopes, Eloísa A. G. L.

    2008-01-01

    Conidia production is a problem in the study of Alternaria alternata from citrus. Thus, this study aimed to compare existing methodologies for conidial production of A. alternata isolated from Ponkan tangerine (2 isolates), Cravo lemon (1 isolate), Pêra orange (2 isolates) and Murcott tangor (1 isolate). The methodologies used were conidia production with 12 and 24 hours under white fluorescent light, evaluation with 24 and 48 hours after applying fungal mycelium stress technique, cold stress followed by injury of mycelium and evaluation with 24 hours, using healthy vegetable tissue and the use of black fluorescent near ultraviolet (NUV) lamp. Satisfactory result was obtained with A. alternata isolate from Murcott tangor, with the production of 2.8 × 105 conidia mL-1, when fungal mycelium was stressed (Petri dish with 66.66% of fungi growth) and subsequently 24 h of growth. The use of white light (24 h) and black fluorescent NUV lamp also induced expressive conidia production by one isolate of Ponkan tangerine, which produced 17.2 × 105 and 10.1 × 105conidia mL-1 and another of Murcott tangor, which produced 13.9 × 105 and 10.1 × 105 conidia mL-1, respectively. The remaining methodologies analyzed in this study were not able to induce conidia production in satisfactory quantity. The use of both mycelium stress technique and white light (24 h) and black fluorescent NUV lamp allowed the production of enough quantities of conidia to be used in vitro (detection of fungitoxic substances) and in vivo (pathogenicity test) assays, respectively. PMID:24031309

  18. Comparison of methodologies for conidia production by Alternaria alternata from citrus.

    PubMed

    Carvalho, Daniel D C; Alves, Eduardo; Batista, Tereza R S; Camargos, Renato B; Lopes, Eloísa A G L

    2008-10-01

    Conidia production is a problem in the study of Alternaria alternata from citrus. Thus, this study aimed to compare existing methodologies for conidial production of A. alternata isolated from Ponkan tangerine (2 isolates), Cravo lemon (1 isolate), Pêra orange (2 isolates) and Murcott tangor (1 isolate). The methodologies used were conidia production with 12 and 24 hours under white fluorescent light, evaluation with 24 and 48 hours after applying fungal mycelium stress technique, cold stress followed by injury of mycelium and evaluation with 24 hours, using healthy vegetable tissue and the use of black fluorescent near ultraviolet (NUV) lamp. Satisfactory result was obtained with A. alternata isolate from Murcott tangor, with the production of 2.8 × 10(5) conidia mL(-1), when fungal mycelium was stressed (Petri dish with 66.66% of fungi growth) and subsequently 24 h of growth. The use of white light (24 h) and black fluorescent NUV lamp also induced expressive conidia production by one isolate of Ponkan tangerine, which produced 17.2 × 10(5) and 10.1 × 10(5)conidia mL(-1) and another of Murcott tangor, which produced 13.9 × 10(5) and 10.1 × 10(5) conidia mL(-1), respectively. The remaining methodologies analyzed in this study were not able to induce conidia production in satisfactory quantity. The use of both mycelium stress technique and white light (24 h) and black fluorescent NUV lamp allowed the production of enough quantities of conidia to be used in vitro (detection of fungitoxic substances) and in vivo (pathogenicity test) assays, respectively.

  19. Temperature, water activity and pH during conidia production affect the physiological state and germination time of Penicillium species.

    PubMed

    Nguyen Van Long, Nicolas; Vasseur, Valérie; Coroller, Louis; Dantigny, Philippe; Le Panse, Sophie; Weill, Amélie; Mounier, Jérôme; Rigalma, Karim

    2017-01-16

    Conidial germination and mycelial growth are generally studied with conidia produced under optimal conditions to increase conidial yield. Nonetheless, the physiological state of such conidia most likely differs from those involved in spoilage of naturally contaminated food. The present study aimed at investigating the impact of temperature, pH and water activity (aw) during production of conidia on the germination parameters and compatible solutes of conidia of Penicillium roqueforti and Penicillium expansum. Low temperature (5°C) and reduced aw (0.900 aw) during sporulation significantly reduced conidial germination times whereas the pH of the sporulation medium only had a slight effect at the tested values (2.5, 8.0). Conidia of P. roqueforti produced at 5°C germinated up to 45h earlier than those produced at 20°C. Conidia of P. roqueforti and P. expansum produced at 0.900 aw germinated respectively up to 8h and 3h earlier than conidia produced at 0.980 aw. Furthermore, trehalose and mannitol assessments suggested that earlier germination might be related to delayed conidial maturation even though no ultra-structural modifications were observed by transmission electron microscopy. Taken together, these results highlight the importance of considering environmental conditions during sporulation in mycological studies. The physiological state of fungal conidia should be taken into account to design challenge tests or predictive mycology studies. This knowledge may also be of interest to improve the germination capacity of fungal cultures commonly used in fermented foods.

  20. Growth of Cognitive Abilities: Dynamic Models and Scaling.

    ERIC Educational Resources Information Center

    Eckstein, Shulamith Graus

    2000-01-01

    Extends dynamic model of cognitive growth proposed by van Geert in three directions: (1) added a term to consider exposure to material to be learned; (2) developed method to apply model to cross-sectional studies; and (3) developed procedure to scale cognitive abilities tests with items of varying difficulty. Tests model with 2- to 15-year-olds'…

  1. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-04-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells.

  2. Inhibitory effect of deferoxamine or macrophage activation on transformation of Paracoccidioides brasiliensis conidia ingested by macrophages: reversal by holotransferrin.

    PubMed Central

    Cano, L E; Gomez, B; Brummer, E; Restrepo, A; Stevens, D A

    1994-01-01

    Conidia of P. brasiliensis ingested by murine macrophages at 37 degrees C showed enhanced transformation to yeast cells and further intracellular growth compared with conidia in culture medium alone. Treatment of macrophages with the iron chelator deferoxamine inhibited the intracellular conidium-to-yeast transformation. Cytokine-activated macrophages could also exert this inhibitory effect. Holotransferrin reversed the inhibitory effect of either deferoxamine or activated macrophages on intracellular conidium-to-yeast transformation. These results indicate that iron restriction is one of the mechanisms by which activated macrophages control the intracellular transformation of ingested conidia and growth of yeast cells. PMID:8132359

  3. Trichothecene mycotoxins in aerosolized conidia of Stachybotrys atra.

    PubMed Central

    Sorenson, W G; Frazer, D G; Jarvis, B B; Simpson, J; Robinson, V A

    1987-01-01

    Stachybotrys atra is the etiologic agent of stachybotryotoxicosis, and this fungus and its trichothecene mycotoxins were recently implicated in an outbreak of unexplained illness in homes. S. atra was grown on sterile rice, autoclaved, dried, and then aerosolized by acoustic vibration. The distribution of particles (mass and number) was monitored on an aerodynamic particle sizer interfaced with a computer. Dust was collected on preweighed glass-fiber filters and extracted with 90% aqueous methanol. Extracts were tested for the ability to inhibit protein synthesis in rat alveolar macrophages, the ability to inhibit the proliferation of mouse thymocytes, and the presence of specific trichothecene mycotoxins. Virtually all of the particles were less than 15 micron in aerodynamic diameter, and the mass median diameter was 5 micron. Thus, most of the particles were respirable. Microscopic analysis of the generated dust revealed that ca. 85% of the dust particles were conidia of S. atra, another 6% were hyphal fragments, and the remainder of the particles were unidentifiable. Thus, greater than 90% of the particles were of fungal origin. The extracts strongly inhibited protein synthesis and thymocyte proliferation. Purified satratoxin H was also highly toxic in the same systems. Each of the individual filters contained satratoxin H (average, 9.5 ng/mg of dust). Satratoxin G and trichoverrols A and B were found in lesser amounts in some, but not all, of the filters. The limit of analysis is ca. 50 ng. These results establish that the conidia of S. atra contain trichothecene mycotoxins. In view of the potent toxicity of the trichothecenes, the inhalation of aerosols containing high concentrations of these conidia could be a potential hazard to health. PMID:3496850

  4. [Anaerobic growth ability and alcohol fermentation activity of microscopic fungi].

    PubMed

    Kurakov, A V; Khidirov, K S; Sadykova, V S; Zviagintsev, D G

    2011-01-01

    The method proposed in this study was used to isolate fungi grown under anaerobic conditions and to reveal distinctions in their abundance and species composition in different habitats. The ability of micromycetes of different taxa to grow under anaerobic conditions and ensure alcohol fermentation was determined for a representative sample (344 strains belonging to more than 60 species). The group of fungi growing under anaerobic conditions included species with high, moderate, and low fermentation activity. The ability for anaerobic growth and fermentation depended on the taxonomic affiliation of fungi. In some cases, the expression of these characteristics depended on the habitat from which the strain was isolated. The maximum level of ethanol accumulation in culture liquid (1.2-4.7%) was detected for Absidia spinosa, Aspergillus sp. of group flavus, Aspergillus terreus, Acremonium sp., Mucor circinelloides, Mucor sp., Fusarium oxysporum, F. solani, F. sambucinum, Rhizopus arrhizus var. Arrhizus, Trichoderma atroviride, and Trichoderma sp.

  5. Production of Conidia by the Fungus Metarhizium anisopliae Using Solid-State Fermentation.

    PubMed

    Loera-Corral, Octavio; Porcayo-Loza, Javier; Montesinos-Matias, Roberto; Favela-Torres, Ernesto

    2016-01-01

    This chapter describes the production of conidia by Metarhizium anisopliae using solid-state fermentation. Before production of conidia, procedures for strains conservation, reactivation, and propagation are essential in order to provide genetic stability of the strains. The strain is conserved in freeze-dried vials and then reactivated through insect inoculation. Rice is used as a substrate for the conidia production in two different bioreactors: plastic bags and tubular bioreactor. The CO2 production in the tubular bioreactors is measured with a respirometer; this system allows calculating indirect growth parameters as lag time (tlag) (25-35 h), maximum rate of CO2 production (rCO2 max) (0.5-0.7 mg/gdm h), specific rate of CO2 production (μ) (0.10-0.15 1/h), and final CO2 production (CO2) (100-120 mg/gdm). Conidial yield per gram of dry substrate (gdm) should be above 1 × 10(9) conidia/gdm after 10 days of incubation. Germination and viability of conidia obtained after 10 days of incubation should be above 80 % and 75 %, respectively. Bioassays using of Tenebrio molitor as a host insect should yield a final mortality above 80 %.

  6. Spontaneous Growth and Chemical Reduction Ability of Ge Nanoparticles

    PubMed Central

    Liu, Jun; Liang, Changhao; Tian, Zhenfei; Zhang, Shuyuan; Shao, Guosheng

    2013-01-01

    Forming colloidal solutions containing semiconductor quantum-sized nanoparticles (NPs) with clean surface has been a long-standing scientific challenge. In this contribution, we report a “top-down” method for the fabrication of Ge NPs by laser ablation of a Ge target in deionized water without adding any stabilizing reagents. The initial Ge NPs in amorphous structure showed spontaneous growth behavior by aging Ge colloids in deionized water under ambient temperature, which gradually evolved into a metastable tetragonal structure as an intermediate phase and then transformed into the stable cubic structure, being consistent with the Ostwald's rule of stages for the growth in a metastable system. The laser-induced initial Ge NPs demonstrate a unique and prominent size-dependent chemical reductive ability, which is evidenced by the rapid degradation of organic molecules such as chlorinated aromatic compounds, organic dyes, and reduction of heavy metal Cr(VI) ions.

  7. Maturation of conidia on conidiophores of Aspergillus niger.

    PubMed

    Teertstra, Wieke R; Tegelaar, Martin; Dijksterhuis, Jan; Golovina, Elena A; Ohm, Robin A; Wösten, Han A B

    2017-01-01

    Conidia of Aspergillus niger are produced on conidiophores. Here, maturation of conidia on these asexual reproductive structures was studied. Pigmented conidia that had developed on conidiophores for 2, 5, and 8days were similarly resistant to heat and were metabolically active as shown by CO2 release and conversion of the metabolic probe Tempone. A total number of 645-2421 genes showed a ⩾2-fold change in expression when 2-day-old conidia were compared to 5- and 8-day-old spores. Melanin was extracted more easily from the cell wall of 2-day-old conidia when compared to the older spores. In addition, mannitol content and germination rate of the 2-day-old conidia were higher. Dispersal efficiency by water was lower in the case of the 8-day-old conidia but no differences were observed in dispersal by wind and a hydrophobic moving object. These data and the fact that only a minor fraction of the conidia on a conidiophore were dispersed in the assays imply that a single colony of A. niger releases a heterogeneous population of conidia. This heterogeneity would provide a selective advantage in environments with rapidly changing conditions such as availability of water. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Competitive ability not kinship affects growth of Arabidopsis thaliana accessions.

    PubMed

    Masclaux, Frédéric; Hammond, Robert L; Meunier, Joël; Gouhier-Darimont, Caroline; Keller, Laurent; Reymond, Philippe

    2010-01-01

    In many organisms, individuals behave more altruistically towards relatives than towards unrelated individuals. Here, we conducted a study to determine if the performance of Arabidopsis thaliana is influenced by whether individuals are in competition with kin or non-kin. We selected seven pairs of genetically distinct accessions that originated from local populations throughout Europe. We measured the biomass of one focal plant surrounded by six kin or non-kin neighbours in in vitro growth experiments and counted the number of siliques produced per pot by one focal plant surrounded by four kin or non-kin neighbours. The biomass and number of siliques of a focal plant were not affected by the relatedness of the neighbour. Depending on the accession, a plant performed better or worse in a pure stand than when surrounded by non-kin plants. In addition, whole-genome microarray analyses revealed that there were no genes differentially expressed between kin and non-kin conditions. In conclusion, our study does not provide any evidence for a differential response to kin vs non-kin in A. thaliana. Rather, the outcome of the interaction between kin and non-kin seems to depend on the strength of the competitive abilities of the accessions.

  9. Hypocrea/Trichoderma: species with conidiophore elongations and green conidia.

    PubMed

    Chaverri, Priscila; Castlebury, Lisa A; Overton, Barrie E; Samuels, Gary J

    2003-01-01

    Species of Trichoderma and Hypocrea that have green conidia and sterile or fertile elongations of their conidiophores are described or redescribed and their phylogenetic position explored. The described species include T. crassum, T. fasciculatum, T. fertile, T. hamatum, T. longipile, T. oblongisporum, T. pubescens, T. spirale, T. strictipile, T. strigosum, T. stromaticum, T. tomentosum, Hypocrea aureoviridis f. macrospora, H. ceramica. and H. semiorbis. Trichoderma fasciculatum originally was described from cultures from ascospores of an unidentified Hypocrea specimen; it is considered to be a synonym of T. strictipile. The remaining species of Trichoderma considered here have not been linked to teleomorphs, and the Trichoderma anamorphs of H. aureoviridis f. macrospora and H. semiorbis have not been named. Five new species of Hypocrea are described, viz. H. cremea, H. cuneispora, H. estonica, H. strictipilosa and H. surrotunda. The phylogenetic relationships of these species were inferred based on partial RPB2 and EF-1α DNA sequence data and phenotypic characteristics, including teleomorph, anamorph, colony and growth rates. Trichoderma crassum was found to be a sister species to T. virens, based on molecular sequences and phenotypic data. Hypocrea surrotunda and H. cremea, H. cuneispora and T. longipile, T. fertile and T. oblongisporum, T. tomentosum and H. atrogelatinosa, and T. hamatum and T. pubescens, respectively, were found to be closely related phylogenetically, based on RPB2 and EF-1α gene genealogies. Anamorph and teleomorph phenotype, including conidiophore elongations, phialide morphology, conidial morphology, stroma anatomy and ascospore morphology are not useful predictors of relationships. Despite the shared phenotypic characters of these Trichoderma and Hypocrea species, they are distributed between two major clades of Trichoderma/Hypocrea. Redescriptions and a key to species of Hypocrea/Trichoderma with green conidia and conidiophore

  10. Genes Differentially Expressed in Conidia and Hyphae of Aspergillus fumigatus upon Exposure to Human Neutrophils

    PubMed Central

    Sugui, Janyce A.; Kim, H. Stanley; Zarember, Kol A.; Chang, Yun C.; Gallin, John I.; Nierman, Willian C.; Kwon-Chung, Kyung J.

    2008-01-01

    Background Aspergillus fumigatus is the most common etiologic agent of invasive aspergillosis in immunocompromised patients. Several studies have addressed the mechanism involved in host defense but only few have investigated the pathogen's response to attack by the host cells. To our knowledge, this is the first study that investigates the genes differentially expressed in conidia vs hyphae of A. fumigatus in response to neutrophils from healthy donors as well as from those with chronic granulomatous disease (CGD) which are defective in the production of reactive oxygen species. Methodology/Principal Findings Transcriptional profiles of conidia and hyphae exposed to neutrophils, either from normal donors or from CGD patients, were obtained by using the genome-wide microarray. Upon exposure to either normal or CGD neutrophils, 244 genes were up-regulated in conidia but not in hyphae. Several of these genes are involved in the degradation of fatty acids, peroxisome function and the glyoxylate cycle which suggests that conidia exposed to neutrophils reprogram their metabolism to adjust to the host environment. In addition, the mRNA levels of four genes encoding proteins putatively involved in iron/copper assimilation were found to be higher in conidia and hyphae exposed to normal neutrophils compared to those exposed to CGD neutrophils. Deletants in several of the differentially expressed genes showed phenotypes related to the proposed functions, i.e. deletants of genes involved in fatty acid catabolism showed defective growth on fatty acids and the deletants of iron/copper assimilation showed higher sensitivity to the oxidative agent menadione. None of these deletants, however, showed reduced resistance to neutrophil attack. Conclusion This work reveals the complex response of the fungus to leukocytes, one of the major host factors involved in antifungal defense, and identifies fungal genes that may be involved in establishing or prolonging infections in humans

  11. Cyclic AMP-dependent protein kinase A negatively regulates conidia formation by the tangerine pathotype of Alternaria alternata.

    PubMed

    Tsai, Hsieh-Chin; Yang, Siwy Ling; Chung, Kuang-Ren

    2013-02-01

    The necrotrophic fungal pathogen Alternaria alternata causes brown spot diseases in many citrus cultivars. The FUS3 and SLT2 mitogen-activated protein kinases (MAPK)-mediated signaling pathways have been shown to be required for conidiation. Exogenous application of cAMP to this fungal pathogen decreased conidia formation considerably. This study determined whether a cAMP-activated protein kinase A (PKA) is required for conidiation. Using loss-of-function mutations in PKA catalytic and regulatory subunit-coding genes, we demonstrated that PKA negatively regulates conidiation. Fungal mutants lacking PKA catalytic subunit gene (PKA ( cat )) reduced growth, lacked detectable PKA activity, and produced higher amounts of conidia compared to wild-type. Introduction of a functional copy of PKA ( cat ) into a null mutant partially restored PKA activity and produced wild-type level of conidia. In contrast, fungi lacking PKA regulatory subunit gene (PKA ( reg )) produced detectable PKA activity, exhibited severe growth reduction, formed swelling hyphal segments, and produced no mature conidia. Introduction of the PKA ( reg ) gene to a regulatory subunit mutant restored all phenotypes to wild type. PKA ( reg )-null mutants induced fewer necrotic lesions on citrus compared to wild-type, whereas PKA ( cat ) mutant displayed wild-type virulence. Overall, our studies indicate that PKA and FUS3-mediated signaling pathways apparently have very different roles in the regulation of conidia production and A. alternata pathogenesis in citrus.

  12. Splash dispersal of Phyllosticta citricarpa conidia from infected citrus fruit

    PubMed Central

    Perryman, S. A. M.; Clark, S. J.; West, J. S.

    2014-01-01

    Rain-splash dispersal of Phyllosticta citricarpa (syn. Guignardia citricarpa) conidia (pycnidiospores) from infected oranges was studied in still air and combined with wind. High power microscopy demonstrated the presence of conidia in splash droplets from diseased oranges, which exuded conidia for over one hour during repeated wetting. The largest (5 mm) incident drops produced the highest splashes (up to 41.0 cm). A linear-by-quadratic surface model predicted highest splashes to be 41.91 cm at a horizontal distance of 25.97 cm from the target orange. Large splash droplets contained most conidia (4–5.5 mm splashes averaged 308 conidia), but were splashed <30 cm horizontal distance. Most (80–90%) splashes were <1 mm diameter but carried only 0–4 conidia per droplet. In multiple splash experiments, splashes combined to reach higher maxima (up to 61.7 cm; linear-by-quadratic surface model prediction, 62.1 cm) than in the single splash experiments. In combination with wind, higher wind speeds carried an increasing proportion of splashes downwind travelling horizontally at least 8 m at the highest wind speed tested (7 m/s), due to a small proportion of droplets (<1 mm) being aerosolised. These experiments suggest that P. citricarpa conidia can be dispersed from infected oranges by splashes of water in rainfall events. PMID:25298272

  13. Botrytis cinerea isolates collected from grapes present different requirements for conidia germination.

    PubMed

    Cotoras, Milena; García, Carolina; Mendoza, Leonora

    2009-01-01

    Botrytis cinerea presents high variability in several biological traits, which can be explained by the high degree of genotypic diversity among isolates. Because this genetic variability might be related to phenotypic differences the requirements for conidia germination of three natural isolates (G1, G5 and G11) obtained from grapes and belonging to the same genetic group were analyzed. The results showed that contact with a solid surface was a common requisite for conidia germination of the isolates but they differed in their nutritional requirements to germinate. Isolate G11 was able to germinate in the absence of a carbon or nitrogen source. G1 and G5 required the presence of a carbon source such as glucose, fructose or sucrose. In G11 and G5 isolates a much higher rate of germination was obtained in the presence of sucrose. It was shown with a pharmacological approach that the cAMP stimulated the germination only in those isolates requiring a carbon source. Conidia germination of G1 and G5 was inhibited by EGTA, a calcium chelator. Isolate G11 germinated in the presence of this compound. On the other hand the germination of three B. cinerea isolates required protein synthesis and did not require RNA synthesis. To explain the ability of isolate G11 to germinate in water the content of total and reducing sugars, mannitol/L-arabitol, trehalose, and proteins in the nongerminated conidia of the three isolates was compared. The isolates presented similar amounts of total and reducing sugars. In the three isolates the amount of mannitol/L-arabitol was higher than that of trehalose. In isolate G11 total protein content was twice higher than in the other isolates.

  14. Exploring Latent Class Based on Growth Rates in Number Sense Ability

    ERIC Educational Resources Information Center

    Kim, Dongil; Shin, Jaehyun; Lee, Kijyung

    2013-01-01

    The purpose of this study was to explore latent class based on growth rates in number sense ability by using latent growth class modeling (LGCM). LGCM is one of the noteworthy methods for identifying growth patterns of the progress monitoring within the response to intervention framework in that it enables us to analyze latent sub-groups based not…

  15. Exploring Latent Class Based on Growth Rates in Number Sense Ability

    ERIC Educational Resources Information Center

    Kim, Dongil; Shin, Jaehyun; Lee, Kijyung

    2013-01-01

    The purpose of this study was to explore latent class based on growth rates in number sense ability by using latent growth class modeling (LGCM). LGCM is one of the noteworthy methods for identifying growth patterns of the progress monitoring within the response to intervention framework in that it enables us to analyze latent sub-groups based not…

  16. Location of Aryl Sulfatase in Conidia and Young Mycelia of Neurospora crassa

    PubMed Central

    Scott, Walter A.; Metzenberg, Robert L.

    1970-01-01

    Aryl sulfatase (arylsulfate sulfohydrolase, EC 3.1.6.1) was found to have multiple locations in Neurospora conidia. Some enzyme activity remained in the supernatant when a spore suspension was centrifuged or filtered. Part of the cell-bound activity could be detected by adding the assay ingredients to a suspension of intact spores (patent enzyme), and additional activity was only detectable when the spores were first treated to destroy their permeability barriers (cryptic enzyme). Such treatments include: disruption with an X-press, brief rinsing with chloroform or acetone, incubation at 60 C for 5 min, and incubation with phenethyl alcohol, nystatin, or ascosin. Part of the patent aryl sulfatase was inactivated by briefly acid treating the intact spores (no loss of conidial viability). This enzyme was considered to have a cell surface location. Some enzyme was acid-resistant in intact spores, but all of the enzyme was acid-sensitive in spores whose permeability barriers had been disrupted. The pH dependence, kinetic properties, and p-nitrophenyl sulfate uptake were investigated in acid-treated conidia. No aryl sulfatase was detected in ascospores. Young mycelia contained more aryl sulfatase than did conidia, but little, if any, was secreted into the growth medium. Cryptic activity was demonstrated in young mycelia by brief chloroform treatment or by rinsing the cells with 0.1 m acetate buffer. Enzyme activity in young mycelia was completely labile to acid treatment, as was cell viability. PMID:16559101

  17. Development of Carrot Medium Suitable for Conidia Production of Venturia nashicola

    PubMed Central

    Choi, Eu Ddeum; Kim, Gyoung Hee; Lee, Young Sun; Jung, Jae Sung; Song, Jang Hoon; Koh, Young Jin

    2017-01-01

    The causal fungus of pear scab, Venturia nashicola, grows slowly and rarely produces conidia on artificial media in the laboratory, but it produced conidia on the Cheongah medium containing Cheongah powder. V. nashicola grew too slow to produce conidia until 15 days after cultivation but produced conidia with 4 × 104 conidia/plate 30 days after cultivation on the Cheongah medium containing 1% Cheongah powder. V. nashicola showed a peak production of conidia with 4.5 × 105 conidia/plate 60 days after cultivation on the carrot medium containing 2% carrot powder, one of the constituents of Cheongah powder. The carrot medium is considered to be the best medium to obtain conidia of V. nashicola in the laboratory until now. This is the first report on the development of a suitable medium for conidia production of V. nashicola, as far as we know. PMID:28167890

  18. Quantitative Genetic Analysis of Latent Growth Curve Models of Cognitive Abilities in Adulthood

    ERIC Educational Resources Information Center

    Reynolds, Chandra A.; Finkel, Deborah; McArdle, John J.; Gatz, Margaret; Berg, Stig; Pedersen, Nancy L.

    2005-01-01

    Though many cognitive abilities exhibit marked decline over the adult years, individual differences in rates of change have been observed. In the current study, biometrical latent growth models were used to examine sources of variability for ability level (intercept) and change (linear and quadratic effects) for verbal, fluid, memory, and…

  19. The Groove of Growth: How Early Gains in Math Ability Influence Adolescent Achievement

    ERIC Educational Resources Information Center

    Watts, Tyler W.; Duncan, Greg J.; Siegler, Robert S.; Davis-Kean, Pamela E.

    2014-01-01

    A number of studies, both small scale and of nationally-representative student samples, have reported substantial associations between school entry math ability and later elementary school achievement. However, questions remain regarding the persistence of the association between early growth in math ability and later math achievement due to the…

  20. Acquisition of lethal doses of Beauveria bassiana conidia by western flower thrips, Frankliniella occidentalis, exposed to foliar spray residues of formulated and unformulated conidia.

    PubMed

    Ugine, Todd A; Wraight, Stephen P; Sanderson, John P

    2005-09-01

    Secondary acquisition of Beauveria bassiana conidia was recorded on the whole bodies and selected body parts of second-instar nymphs and adult female western flower thrips exposed to foliar spray residues of three differently formulated conidial preparations, for 24 h. Conidia were formulated in emulsifiable oil or with clay (wettable powder), or were essentially unformulated conidia (technical grade powder suspended in water with a surfactant). Formulation had no significant effect on dose acquisition and no effect on virulence of acquired conidia. The mean nymphal LC50/LD50 was 116 conidia/mm2 and 52conidia/insect, respectively; the values for adults were 19 conidia/mm2 and 5conidia/insect. Greatest numbers of conidia were recorded on the legs and abdomens of nymphs and on the legs, wings, and thoraces of adults. As would be expected, numbers of conidia acquired increased with residue concentration (application rate). However, an inverse relationship was noted between acquisition rate (conidia acquired/total conidia applied) and residue concentration. The mechanism underlying this response was not determined. However, there was no indication that any body parts (e.g., tarsi) became saturated with spores, which suggests that either the thrips were repelled by the conidial residues or that as the concentrations of conidia on the substrate increased, conidia somehow became more difficult to acquire. Slopes of the LC probit regressions were lower than those of the LD regressions (mean 1.14 vs 1.78), suggesting that the low slopes often obtained in fungal pathogen assays could be partly an artifact of unequal rates of dose acquisition at low vs high application rates.

  1. Digitomyces, a new genus of hyphomycetes with cheiroid conidia.

    PubMed

    Mercado Sierra, Angel; Calduch, Misericordia; Gené, Josepa; Guarro, Josep; Delgado, Gregorio

    2003-01-01

    The new anamorphic genus Digitomyces, based on Dictyosporium verrucosum, is proposed. It is characterized by micronematous or semimacronematous conidiophores, integrated or discrete, holoblastic, determinate conidiogenous cells, and olivaceous to pale brown, verrucose, cheiroid conidia, with a truncate basal cell and (2-)3 arms. The new taxon is compared with morphologically similar anamorph genera.

  2. Cognitive ability in adolescents born small for gestational age: Associations with fetal growth velocity, head circumference and postnatal growth.

    PubMed

    Jensen, Rikke Beck; Juul, Anders; Larsen, Torben; Mortensen, Erik Lykke; Greisen, Gorm

    2015-12-01

    Small size at birth may be associated with impaired cognitive ability later in life. The aim of this study was to examine the effect of being born small for gestational age (SGA), with or without intrauterine growth restriction (IUGR) on cognitive ability in late adolescence. A follow-up study of a former cohort included 123 participants (52 males); 47 born SGA and 76 born appropriate for gestational age (AGA). Fetal growth velocity (FGV) was determined by serial ultrasound measurements during the third trimester. A control group matched for age and birthplace was included. The original Wechsler Adult Intelligence Scale (WAIS) was administered, and verbal, performance and full-scale Intelligence Quotient (IQ) scores were calculated. There was no difference in IQ between adolescents born SGA and AGA. FGV or IUGR during the third trimester did not influence cognitive ability in late adolescence. Full-scale IQ was positively related to head circumference (HC) in adolescence (B: 1.30, 95% CI: 0.32-2.28, p=0.01). HC at birth and three months was positively associated with full-scale IQ. Catch-up growth in the group of SGA children was associated with a significantly increased height, larger HC, increased levels of insulin-like growth factor-I (IGF-I) and increased full-scale IQ compared to those born SGA without catch-up growth. SGA and IUGR may not be harmful for adult cognitive ability, at least not in individuals born at near-term. However, known risk factors of impaired fetal growth may explain the link between early growth and cognitive ability in adulthood. Copyright © 2015. Published by Elsevier Ireland Ltd.

  3. Modification of a pollen trap design to capture airborne conidia of Entomophaga maimaiga and detection of conidia by quantitative PCR

    Treesearch

    Tonya D. Bittner; Ann E. Hajek; Andrew M. Liebhold; Harold Thistle; Dan Cullen

    2017-01-01

    The goal of this study was to develop effective and practical field sampling methods for quantification of aerial deposition of airborne conidia of Entomophaga maimaiga over space and time. This important fungal pathogen is a major cause of larval death in invasive gypsy moth (Lymantria dispar) populations in the United States...

  4. Detection of Airborne Stachybotrys chartarum Macrocyclic Trichothecene Mycotoxins on Particulates Smaller than Conidia

    PubMed Central

    Brasel, T. L.; Douglas, D. R.; Wilson, S. C.; Straus, D. C.

    2005-01-01

    Highly respirable particles (diameter, <1 μm) constitute the majority of particulate matter found in indoor air. It is hypothesized that these particles serve as carriers for toxic compounds, specifically the compounds produced by molds in water-damaged buildings. The presence of airborne Stachybotrys chartarum trichothecene mycotoxins on particles smaller than conidia (e.g., fungal fragments) was therefore investigated. Cellulose ceiling tiles with confluent Stachybotrys growth were placed in gas-drying containers through which filtered air was passed. Exiting particulates were collected by using a series of polycarbonate membrane filters with decreasing pore sizes. Scanning electron microscopy was employed to determine the presence of conidia on the filters. A competitive enzyme-linked immunosorbent assay (ELISA) specific for macrocyclic trichothecenes was used to analyze filter extracts. Cross-reactivity to various mycotoxins was examined to confirm the specificity. Statistically significant (P < 0.05) ELISA binding was observed primarily for macrocyclic trichothecenes at concentrations of 50 and 5 ng/ml and 500 pg/ml (58.4 to 83.5% inhibition). Of the remaining toxins tested, only verrucarol and diacetylverrucarol (nonmacrocyclic trichothecenes) demonstrated significant binding (18.2 and 51.7% inhibition, respectively) and then only at high concentrations. The results showed that extracts from conidium-free filters demonstrated statistically significant (P < 0.05) antibody binding that increased with sampling time (38.4 to 71.9% inhibition, representing a range of 0.5 to 4.0 ng/ml). High-performance liquid chromatography analysis suggested the presence of satratoxin H in conidium-free filter extracts. These data show that S. chartarum trichothecene mycotoxins can become airborne in association with intact conidia or smaller particles. These findings may have important implications for indoor air quality assessment. PMID:15640178

  5. Detection of airborne Stachybotrys chartarum macrocyclic trichothecene mycotoxins on particulates smaller than conidia.

    PubMed

    Brasel, T L; Douglas, D R; Wilson, S C; Straus, D C

    2005-01-01

    Highly respirable particles (diameter, <1 microm) constitute the majority of particulate matter found in indoor air. It is hypothesized that these particles serve as carriers for toxic compounds, specifically the compounds produced by molds in water-damaged buildings. The presence of airborne Stachybotrys chartarum trichothecene mycotoxins on particles smaller than conidia (e.g., fungal fragments) was therefore investigated. Cellulose ceiling tiles with confluent Stachybotrys growth were placed in gas-drying containers through which filtered air was passed. Exiting particulates were collected by using a series of polycarbonate membrane filters with decreasing pore sizes. Scanning electron microscopy was employed to determine the presence of conidia on the filters. A competitive enzyme-linked immunosorbent assay (ELISA) specific for macrocyclic trichothecenes was used to analyze filter extracts. Cross-reactivity to various mycotoxins was examined to confirm the specificity. Statistically significant (P < 0.05) ELISA binding was observed primarily for macrocyclic trichothecenes at concentrations of 50 and 5 ng/ml and 500 pg/ml (58.4 to 83.5% inhibition). Of the remaining toxins tested, only verrucarol and diacetylverrucarol (nonmacrocyclic trichothecenes) demonstrated significant binding (18.2 and 51.7% inhibition, respectively) and then only at high concentrations. The results showed that extracts from conidium-free filters demonstrated statistically significant (P < 0.05) antibody binding that increased with sampling time (38.4 to 71.9% inhibition, representing a range of 0.5 to 4.0 ng/ml). High-performance liquid chromatography analysis suggested the presence of satratoxin H in conidium-free filter extracts. These data show that S. chartarum trichothecene mycotoxins can become airborne in association with intact conidia or smaller particles. These findings may have important implications for indoor air quality assessment.

  6. Optimization of Solid-State Fermentation for Improved Conidia Production of Beauveria bassiana as a Mycoinsecticide

    PubMed Central

    Pham, Tuan Anh; Kim, Jeong Jun

    2010-01-01

    The production of conidia of entomopathogenic Beauveria bassiana by solid-state fermentation was studied for the development of a biocontrol agent against aphid Myzus persicae. The optimal conditions for conidia production on polished white rice were 40% moisture content, 25℃ culture temperature, 2-day-old seeding culture grown in 3% corn meal, 2% rice bran, 2% corn steep powder medium, initial conidia concentration of 107 conidia/g in the wet rice, 10% inoculum size, and use of a polyethylene bag as a container. The polyethylene bag containing inoculated rice was hand-shaken every 12 hr during fermentation. Using optimal conditions, the maximum conidia production obtained was 4.05 g conidia/100 g dry rice after 14 days of cultivation, a rate 2.83 times higher than conidia yield of pre-optimization. PMID:23956642

  7. The Role of PS Ability and RC Skill in Predicting Growth Trajectories of Mathematics Achievement

    ERIC Educational Resources Information Center

    Vista, Alvin

    2016-01-01

    There are relatively few studies in Australia and South-East Asian region that combine investigating models of math growth trajectories with predictors such as reasoning ability and reading comprehension skills. Math achievement is one of the major components of overall academic achievement and it is important to determine what factors (especially…

  8. Growth and intraspecific competitive abilities of the dioecious Lindera melissifolia (Lauraceae) in varied flooding regimes

    Treesearch

    Tracy S. Hawkins; Nathan M. Schiff; Theodor D. Leininger; Emile S Gardiner; Margaret S. Devall; Paul B. Hamel; A. Dan Wilson; Kristina F. Connor

    2009-01-01

    Forest Service, Southern Research Station, Stoneville, MS 38776). Growth and intraspecific competitive abilities of the dioecious Lindera melissifolia (Lauraceae) in varied flooding regimes. J. Torrey Bot. Soc. 136: 91–101. 2009.—The contribution of sexual dimorphism to malebiased colony ratios observed in field populations of the federally...

  9. Is Overall Oral English Ability Related to Young Latinos' English Reading Growth?

    ERIC Educational Resources Information Center

    Fitzgerald, Jill; Amendum, Steven J.; Relyea, Jackie Eunjung; Garcia, Sandra G.

    2015-01-01

    The present study investigated whether young Latino dual-language learners' 2-year English reading growth varied over time according to their initial overall oral English ability. We followed 41 Latino children for 2 years. We tested overall oral English at the beginning of the study and administered multiple curriculum-based reading assessments…

  10. Is Overall Oral English Ability Related to Young Latinos' English Reading Growth?

    ERIC Educational Resources Information Center

    Fitzgerald, Jill; Amendum, Steven J.; Relyea, Jackie Eunjung; Garcia, Sandra G.

    2015-01-01

    The present study investigated whether young Latino dual-language learners' 2-year English reading growth varied over time according to their initial overall oral English ability. We followed 41 Latino children for 2 years. We tested overall oral English at the beginning of the study and administered multiple curriculum-based reading assessments…

  11. Reading Ability Development from Kindergarten to Junior Secondary: Latent Transition Analyses with Growth Mixture Modeling

    PubMed Central

    Liu, Yuan; Liu, Hongyun; Hau, Kit-tai

    2016-01-01

    The present study examined the reading ability development of children in the large scale Early Childhood Longitudinal Study (Kindergarten Class of 1998-99 data; Tourangeau et al., 2009) under the dynamic systems. To depict children's growth pattern, we extended the measurement part of latent transition analysis to the growth mixture model and found that the new model fitted the data well. Results also revealed that most of the children stayed in the same ability group with few cross-level changes in their classes. After adding the environmental factors as predictors, analyses showed that children receiving higher teachers' ratings, with higher socioeconomic status, and of above average poverty status, would have higher probability to transit into the higher ability group. PMID:27826278

  12. Heterogeneity in liquid shaken cultures of Aspergillus niger inoculated with melanised conidia or conidia of pigmentation mutants.

    PubMed

    van Veluw, G J; Teertstra, W R; de Bekker, C; Vinck, A; van Beek, N; Muller, W H; Arentshorst, M; van der Mei, H C; Ram, A F J; Dijksterhuis, J; Wösten, H A B

    2013-03-15

    Black pigmented conidia of Aspergillus niger give rise to micro-colonies when incubated in liquid shaken medium. These micro-colonies are heterogeneous with respect to gene expression and size. We here studied the biophysical properties of the conidia of a control strain and of strains in which the fwnA, olvA or brnA gene is inactivated. These strains form fawn-, olive-, and brown-coloured conidia, respectively. The ΔolvA strain produced larger conidia (3.8 μm) when compared to the other strains (3.2-3.3 μm). Moreover, the conidia of the ΔolvA strain were highly hydrophilic, whereas those of the other strains were hydrophobic. The zeta potential of the ΔolvA conidia in medium was also more negative when compared to the control strain. This was accompanied by the near absence of a rodlet layer of hydrophobins. Using the Complex Object Parametric Analyzer and Sorter it was shown that the ratio of individual hyphae and micro-colonies in liquid shaken cultures of the deletion strains was lower when compared to the control strain. The average size of the micro-colonies of the control strain was also smaller (628 μm) than that of the deletion strains (790-858 μm). The size distribution of the micro-colonies of the ΔfwnA strain was normally distributed, while that of the other strains could be explained by assuming a population of small and a population of large micro-colonies. In the last set of experiments it was shown that relative expression levels of gpdA, and AmyR and XlnR regulated genes correlate in individual hyphae at the periphery of micro-colonies. This indicates the existence of transcriptionally and translationally highly active and lowly active hyphae as was previously shown in macro-colonies. However, the existence of distinct populations of hyphae with high and low transcriptional and translational activity seems to be less robust when compared to macro-colonies grown on solid medium.

  13. Melanin dependent survival of Apergillus fumigatus conidia in lung epithelial cells.

    PubMed

    Amin, Shayista; Thywissen, Andreas; Heinekamp, Thorsten; Saluz, Hans Peter; Brakhage, Axel A

    2014-07-01

    Aspergillus fumigatus is the most important air-borne pathogenic fungus of humans. Upon inhalation of conidia, the fungus makes close contact with lung epithelial cells, which only possess low phagocytic activity. These cells are in particular interesting to address the question whether there is some form of persistence of conidia of A. fumigatus in the human host. Therefore, by also using uracil-auxotrophic mutant strains, we were able to investigate the interaction of A549 lung epithelial cells and A. fumigatus conidia in detail for long periods. Interestingly, unlike professional phagocytes, our study showed that the presence of conidial dihydroxynaphthalene (DHN) melanin enhanced the uptake of A. fumigatus conidia by epithelial cells when compared with non-pigmented pksP mutant conidia. Furthermore, conidia of A. fumigatus were able to survive within epithelial cells. This was due to the presence of DHN melanin in the cell wall of conidia, because melanised wild-type conidia showed a higher survival rate inside epithelial cells and led to inhibition of acidification of phagolysosomes. Both effects were not observed for white (non-melanised) conidia of the pksP mutant strain. Moreover, in contrast to pksP mutant conidia, melanised wild-type conidia were able to inhibit the extrinsic apoptotic pathway in A549 lung epithelial cells even for longer periods. The anti-apoptotic effect was not restricted to conidia, because both conidia-derived melanin ghosts (cell-free DHN melanin) and a different type of melanin, dihydroxyphenylalanine (DOPA) melanin, acted anti-apoptotically. Taken together, these data indicate the possibility of melanin-dependent persistence of conidia in lung epithelial cells.

  14. Automated quantification of the phagocytosis of Aspergillus fumigatus conidia by a novel image analysis algorithm

    PubMed Central

    Kraibooj, Kaswara; Schoeler, Hanno; Svensson, Carl-Magnus; Brakhage, Axel A.; Figge, Marc Thilo

    2015-01-01

    Studying the pathobiology of the fungus Aspergillus fumigatus has gained a lot of attention in recent years. This is due to the fact that this fungus is a human pathogen that can cause severe diseases, like invasive pulmonary aspergillosis in immunocompromised patients. Because alveolar macrophages belong to the first line of defense against the fungus, here, we conduct an image-based study on the host-pathogen interaction between murine alveolar macrophages and A. fumigatus. This is achieved by an automated image analysis approach that uses a combination of thresholding, watershed segmentation and feature-based object classification. In contrast to previous approaches, our algorithm allows for the segmentation of individual macrophages in the images and this enables us to compute the distribution of phagocytosed and macrophage-adherent conidia over all macrophages. The novel automated image-based analysis provides access to all cell-cell interactions in the assay and thereby represents a framework that enables comprehensive computation of diverse characteristic parameters and comparative investigation for different strains. We here apply automated image analysis to confocal laser scanning microscopy images of the two wild-type strains ATCC 46645 and CEA10 of A. fumigatus and investigate the ability of macrophages to phagocytose the respective conidia. It is found that the CEA10 strain triggers a stronger response of the macrophages as revealed by a higher phagocytosis ratio and a larger portion of the macrophages being active in the phagocytosis process. PMID:26106370

  15. Photodynamic inactivation of Penicillium chrysogenum conidia by cationic porphyrins.

    PubMed

    Gomes, Maria C; Woranovicz-Barreira, Sandra M; Faustino, Maria A F; Fernandes, Rosa; Neves, Maria G P M S; Tomé, Augusto C; Gomes, Newton C M; Almeida, Adelaide; Cavaleiro, José A S; Cunha, Angela; Tomé, João P C

    2011-11-01

    This work reports the photophysical and biological evaluation of five cationic porphyrins as photosensitizers (PS) for the photodynamic inactivation (PDI) of Penicillium chrysogenum conidia. Two different cationic porphyrin groups were synthesized from 5,10,15,20-tetrakis(4-pyridyl)porphyrin and 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin. The photostability and singlet oxygen generation studies showed that these molecules are photostable and efficient singlet oxygen generators. PDI experiments of P. chrysogenum conidia conducted with 50 μmol L(-1) of photosensitiser under white light at a fluence rate of 200 mW cm(-2) over 20 min showed that the most effective PS caused a 4.1 log reduction in the concentration of viable conidia. The present results show that porphyrins 1a and 1b are more efficient PSs than porphyrin 2a while porphyrins 1c and 2b show no inactivation of P. chrysogenum. It is also clear that the effectiveness of the molecule as PS for antifungal PDI is strongly related with the porphyrin substituent groups, and consequently their solubility in physiological media. The average amount of PS adsorbed per viable conidium was a determining factor in the photoinactivation efficiency and varied between the different studied PSs. Cationic PSs 1a and 1b might be promising anti-fungal PDI agents with potential applications in phytosanitation, biofilm control, bioremediation, and wastewater treatment.

  16. Preparation of fungal conidia impacts their susceptibility to inactivation by ethanol vapours.

    PubMed

    Dao, Thien; Dantigny, Philippe

    2009-11-15

    A common protocol employed for the preparation of conidia employs flooding a fungal colony grown on semi-solid media under optimum conditions with an aqueous solution. In contrast, conidia produced in a natural environment are usually not hydrated when disseminated in air and can be produced under water stress. In order to simulate the latter conditions, cultures were grown at different water activities and conidia were dry-harvested on the lid by turning the dishes upside-down then gently tapping the bottom of the box. This study aimed at assessing the effect of the preparation of fungal conidia on their inactivation by ethanol vapours. Firstly ethanol vapours (either 0.30 or 0.45 kPa) were applied to conidia obtained from the standardised protocol and to dry-harvested conidia for some species of Penicillium. While all dry-harvested conidia remained viable after 24 h of treatment, about 1.0, 3.5 and 2.5 log(10) reductions were observed for hydrated conidia of Penicillium chrysogenum, Penicillium digitatum and Penicillium italicum respectively. Secondly ethanol vapours (0.67 kPa) were applied to dry-harvested conidia obtained from cultures grown at 0.99 a(w) and at reduced water activities. For all species, the susceptibility to ethanol vapours of conidia obtained at 0.99 a(w) was significantly greater than that of conidia obtained at reduced water activities. Conidia produced in a natural environment under non-optimal conditions would be much more resistant to ethanol vapours than those produced in the laboratory. This phenomenon may be due to a reduced intracellular water activity of dry-harvested conidia.

  17. Brain Structural Integrity and Intrinsic Functional Connectivity Forecast 6 Year Longitudinal Growth in Children's Numerical Abilities

    PubMed Central

    Kochalka, John; Ngoon, Tricia J.; Wu, Sarah S.; Qin, Shaozheng; Battista, Christian

    2015-01-01

    Early numerical proficiency lays the foundation for acquiring quantitative skills essential in today's technological society. Identification of cognitive and brain markers associated with long-term growth of children's basic numerical computation abilities is therefore of utmost importance. Previous attempts to relate brain structure and function to numerical competency have focused on behavioral measures from a single time point. Thus, little is known about the brain predictors of individual differences in growth trajectories of numerical abilities. Using a longitudinal design, with multimodal imaging and machine-learning algorithms, we investigated whether brain structure and intrinsic connectivity in early childhood are predictive of 6 year outcomes in numerical abilities spanning childhood and adolescence. Gray matter volume at age 8 in distributed brain regions, including the ventrotemporal occipital cortex (VTOC), the posterior parietal cortex, and the prefrontal cortex, predicted longitudinal gains in numerical, but not reading, abilities. Remarkably, intrinsic connectivity analysis revealed that the strength of functional coupling among these regions also predicted gains in numerical abilities, providing novel evidence for a network of brain regions that works in concert to promote numerical skill acquisition. VTOC connectivity with posterior parietal, anterior temporal, and dorsolateral prefrontal cortices emerged as the most extensive network predicting individual gains in numerical abilities. Crucially, behavioral measures of mathematics, IQ, working memory, and reading did not predict children's gains in numerical abilities. Our study identifies, for the first time, functional circuits in the human brain that scaffold the development of numerical skills, and highlights potential biomarkers for identifying children at risk for learning difficulties. SIGNIFICANCE STATEMENT Children show substantial individual differences in math abilities and ease of math

  18. Brain Structural Integrity and Intrinsic Functional Connectivity Forecast 6 Year Longitudinal Growth in Children's Numerical Abilities.

    PubMed

    Evans, Tanya M; Kochalka, John; Ngoon, Tricia J; Wu, Sarah S; Qin, Shaozheng; Battista, Christian; Menon, Vinod

    2015-08-19

    Early numerical proficiency lays the foundation for acquiring quantitative skills essential in today's technological society. Identification of cognitive and brain markers associated with long-term growth of children's basic numerical computation abilities is therefore of utmost importance. Previous attempts to relate brain structure and function to numerical competency have focused on behavioral measures from a single time point. Thus, little is known about the brain predictors of individual differences in growth trajectories of numerical abilities. Using a longitudinal design, with multimodal imaging and machine-learning algorithms, we investigated whether brain structure and intrinsic connectivity in early childhood are predictive of 6 year outcomes in numerical abilities spanning childhood and adolescence. Gray matter volume at age 8 in distributed brain regions, including the ventrotemporal occipital cortex (VTOC), the posterior parietal cortex, and the prefrontal cortex, predicted longitudinal gains in numerical, but not reading, abilities. Remarkably, intrinsic connectivity analysis revealed that the strength of functional coupling among these regions also predicted gains in numerical abilities, providing novel evidence for a network of brain regions that works in concert to promote numerical skill acquisition. VTOC connectivity with posterior parietal, anterior temporal, and dorsolateral prefrontal cortices emerged as the most extensive network predicting individual gains in numerical abilities. Crucially, behavioral measures of mathematics, IQ, working memory, and reading did not predict children's gains in numerical abilities. Our study identifies, for the first time, functional circuits in the human brain that scaffold the development of numerical skills, and highlights potential biomarkers for identifying children at risk for learning difficulties. Children show substantial individual differences in math abilities and ease of math learning. Early

  19. [Genotypic analysis and plant growth-promoting ability of four plant growth-promoting bacteria from mangrove].

    PubMed

    Lu, Junkun; Chen, Jun; Kang, Lihua

    2010-10-01

    We identified four strains of plant growth-promoting bacteria (PGPB) and their plant growth-promoting ability. Four PGPB strains were genetically analyzed by PCR detection of nifH and 16S rRNA gene. Phosphate-solubilizing and nitrogen-fixation capacity were examined by spectrophotometric quantification and acetylene reduction assay, respectively. Effect of strain inoculation on plant growth was also evaluated. Phylogenetic analysis based on nifH and 16S rRNA gene sequences indicated that strain HN011 was mostly related to Vibrio natriegens, and SZ7-1 and SZ7-2 resembled Klebsiella oxytoca. Although similarity of 16S rRNA sequence showed that SZ002 belongs to Paenibacillus sp., nifH gene of SZ002 had high sequence similarity with Klebsiella genus. Phosphate solubilization showed that insoluble phosphate was well solubilized in the liquid medium by all four strains of PGPB, which also had high nitrogen-fixation capacity. Plant dry weight, total N and total P were higher in some inoculated than in the non-inoculated plants (P < 0.05). Our results showed that all four strains of PGPB isolated from mangrove had both phosphate solubilization and nitrogen fixation ability, resulting in beneficial effects on growth.

  20. Threshold response of stomatal closing ability to leaf abscisic acid concentration during growth

    PubMed Central

    Giday, Habtamu; Fanourakis, Dimitrios; Kjaer, Katrine H.; Fomsgaard, Inge S.; Ottosen, Carl-Otto

    2014-01-01

    Leaf abscisic acid concentration ([ABA]) during growth influences morpho-physiological traits associated with the plant’s ability to cope with stress. A dose–response curve between [ABA] during growth and the leaf’s ability to regulate water loss during desiccation or rehydrate upon re-watering was obtained. Rosa hybrida plants were grown at two relative air humidities (RHs, 60% or 90%) under different soil water potentials (–0.01, –0.06, or –0.08MPa) or upon grafting onto the rootstock of a cultivar sustaining [ABA] at elevated RH. Measurements included [ABA], stomatal anatomical features, stomatal responsiveness to desiccation, and the ability of leaves, desiccated to varying degrees, to recover their weight (rehydrate) following re-watering. Transpiration efficiency (plant mass per transpired water) was also determined. Soil water deficit resulted in a lower transpiration rate and higher transpiration efficiency at both RHs. The lowest [ABA] was observed in well-watered plants grown at high RH. [ABA] was increased by soil water deficit or grafting, at both RHs. The growth environment-induced changes in stomatal size were mediated by [ABA]. When [ABA] was increased from the level of (well-watered) high RH-grown plants to the value of (well-watered) plants grown at moderate RH, stomatal responsiveness was proportionally improved. A further increase in [ABA] did not affect stomatal responsiveness to desiccation. [ABA] was positively related to the ability of dehydrated leaves to rehydrate. The data indicate a growth [ABA]-related threshold for stomatal sensitivity to desiccation, which was not apparent either for stomatal size or for recovery (rehydration) upon re-watering. PMID:24863434

  1. Threshold response of stomatal closing ability to leaf abscisic acid concentration during growth.

    PubMed

    Giday, Habtamu; Fanourakis, Dimitrios; Kjaer, Katrine H; Fomsgaard, Inge S; Ottosen, Carl-Otto

    2014-08-01

    Leaf abscisic acid concentration ([ABA]) during growth influences morpho-physiological traits associated with the plant's ability to cope with stress. A dose-response curve between [ABA] during growth and the leaf's ability to regulate water loss during desiccation or rehydrate upon re-watering was obtained. Rosa hybrida plants were grown at two relative air humidities (RHs, 60% or 90%) under different soil water potentials (-0.01, -0.06, or -0.08MPa) or upon grafting onto the rootstock of a cultivar sustaining [ABA] at elevated RH. Measurements included [ABA], stomatal anatomical features, stomatal responsiveness to desiccation, and the ability of leaves, desiccated to varying degrees, to recover their weight (rehydrate) following re-watering. Transpiration efficiency (plant mass per transpired water) was also determined. Soil water deficit resulted in a lower transpiration rate and higher transpiration efficiency at both RHs. The lowest [ABA] was observed in well-watered plants grown at high RH. [ABA] was increased by soil water deficit or grafting, at both RHs. The growth environment-induced changes in stomatal size were mediated by [ABA]. When [ABA] was increased from the level of (well-watered) high RH-grown plants to the value of (well-watered) plants grown at moderate RH, stomatal responsiveness was proportionally improved. A further increase in [ABA] did not affect stomatal responsiveness to desiccation. [ABA] was positively related to the ability of dehydrated leaves to rehydrate. The data indicate a growth [ABA]-related threshold for stomatal sensitivity to desiccation, which was not apparent either for stomatal size or for recovery (rehydration) upon re-watering.

  2. Role of iron in the nitric oxide-mediated fungicidal mechanism of IFN-gamma-activated murine macrophages against Paracoccidioides brasiliensis conidia.

    PubMed

    Gonzalez, Angel; Restrepo, Angela; Cano, Luz E

    2007-01-01

    Iron is an essential growth element of virtually all microorganisms and its restriction is one of the mechanisms used by macrophages to control microbial multiplication. Paracoccidioides brasiliensis, the agent of paracoccidioidomycosis, an important systemic mycosis in Latin America, is inhibited in its conidia-to-yeast conversion in the absence of iron. We studied the participation of iron in the nitric oxide (NO)-mediated fungicidal mechanism against conidia. Peritoneal murine macrophages activated with 50 U/mL of IFN-gamma or treated with 35 microM Deferoxamine (DEX) and infected with P. brasiliensis conidia, were co-cultured and incubated for 96 h in the presence of different concentrations of holotransferrin (HOLO) and FeS04. The supernatants were withdrawn in order to assess NO2 production by the Griess method. The monolayers were fixed, stained and observed microscopically. The percentage of the conidia-to-yeast transition was estimated by counting 200 intracellular propagules. IFN-gamma-activated or DEX-treated Mthetas presented marked inhibition of the conidia-to-yeast conversion (19 and 56%, respectively) in comparison with non-activated or untreated Mthetas (80%). IFN-gamma-activated macrophages produced high NO levels in comparison with the controls. Additionally, when the activated or treated-macrophages were supplemented with iron donors (HOLO or FeSO4), the inhibitory action was reversed, although NO production remained intact. These results suggest that the NO-mediated fungicidal mechanism exerted by IFN-gamma-activated macrophages against P. brasiliensis conidia, is dependent of an iron interaction.

  3. The pbrB gene encodes a laccase required for DHN-melanin synthesis in conidia of Talaromyces (Penicillium) marneffei.

    PubMed

    Sapmak, Ariya; Boyce, Kylie J; Andrianopoulos, Alex; Vanittanakom, Nongnuch

    2015-01-01

    Talaromyces marneffei (Basionym: Penicillium marneffei) is a significant opportunistic fungal pathogen in patients infected with human immunodeficiency virus in Southeast Asia. T. marneffei cells have been shown to become melanized in vivo. Melanins are pigment biopolymers which act as a non-specific protectant against various stressors and which play an important role during virulence in fungi. The synthesis of the two most commonly found melanins in fungi, the eumelanin DOPA-melanin and the allomelanin DHN-melanin, requires the action of laccase enzymes. The T. marneffei genome encodes a number of laccases and this study describes the characterization of one of these, pbrB, during growth and development. A strain carrying a PbrB-GFP fusion shows that pbrB is expressed at high levels during asexual development (conidiation) but not in cells growing vegetatively. The pbrB gene is required for the synthesis of DHN-melanin in conidia and when deleted results in brown pigmented conidia, in contrast to the green conidia of the wild type.

  4. The pbrB Gene Encodes a Laccase Required for DHN-Melanin Synthesis in Conidia of Talaromyces (Penicillium) marneffei

    PubMed Central

    Sapmak, Ariya; Boyce, Kylie J.; Andrianopoulos, Alex; Vanittanakom, Nongnuch

    2015-01-01

    Talaromyces marneffei (Basionym: Penicillium marneffei) is a significant opportunistic fungal pathogen in patients infected with human immunodeficiency virus in Southeast Asia. T. marneffei cells have been shown to become melanized in vivo. Melanins are pigment biopolymers which act as a non-specific protectant against various stressors and which play an important role during virulence in fungi. The synthesis of the two most commonly found melanins in fungi, the eumelanin DOPA-melanin and the allomelanin DHN-melanin, requires the action of laccase enzymes. The T. marneffei genome encodes a number of laccases and this study describes the characterization of one of these, pbrB, during growth and development. A strain carrying a PbrB-GFP fusion shows that pbrB is expressed at high levels during asexual development (conidiation) but not in cells growing vegetatively. The pbrB gene is required for the synthesis of DHN-melanin in conidia and when deleted results in brown pigmented conidia, in contrast to the green conidia of the wild type. PMID:25866870

  5. A proposed role for the cuticular fatty amides of Liposcelis bostrychophila (Psocoptera: Liposcelidae) in preventing adhesion of entomopathogenic fungi with dry-conidia.

    PubMed

    Lord, Jeffrey C; Howard, Ralph W

    2004-08-01

    Maximum challenge exposure of Liposcelis bostrychophila to Beauveria bassiana, Paecilomyces fumosoroseus, Aspergillus parasiticus or Metarhizium anisopliae resulted in no more than 16% mortality. We investigated several of L. bostrychophila's cuticular lipids for possible contributions to its tolerance for entomopathogenic fungi. Saturated C14 and C16 fatty acids did not reduce the germination rates of B. bassiana or M. anisopliae conidia. Saturated C6 to C12 fatty acids that have not been identified in L. bostrychophila cuticular extracts significantly reduced germination, but the reduction was mitigated by the presence of stearamide. Cis-6-hexadecenal did not affect germination rates. Mycelial growth of either fungal species did not occur in the presence of caprylic acid, was reduced by the presence of lauric acid, and was not significantly affected by palmitic acid. Liposcelis bostrychophila is the only insect for which fatty acid amides have been identified as cuticular components. Stearamide, its major fatty amide, did not reduce germination of B. bassiana or M. anisopliae conidia or growth of their mycelia. Adhesion of conidia to stearamide preparations did not differ significantly from adhesion to the cuticle of L. bostrychophila. Pretreatment of a beetle known to be fungus-susceptible, larval Oryzaephilus surinamensis, with stearamide significantly decreased adhesion of B. bassiana or M. anisopliae conidia to their cuticles. This evidence indicates that cuticular fatty amides may contribute to L. bostrychophila's tolerance for entomopathogenic fungi by decreasing hydrophobicity and static charge, thereby reducing conidial adhesion.

  6. Ability of organic and inorganic bedding materials to promote growth of environmental bacteria.

    PubMed

    Godden, S; Bey, R; Lorch, K; Farnsworth, R; Rapnicki, P

    2008-01-01

    The major objective of this study was to contrast the ability of 4 commonly utilized bedding materials to promote growth of environmental bacteria under controlled conditions. A second objective was to describe the relationship between bacterial growth and specific biochemical or nutritional properties of these bedding materials. Unused samples of clean sand (CS; n = 20), recycled sand (RS; n = 21), digested manure solids (DS; n = 15), and shavings (SH; n = 15) were collected from bedding storage areas on 49 commercial Minnesota and Wisconsin dairy farms. Sterilized bedding samples were inoculated with Klebsiella pneumoniae and Enterococcus faecium then incubated, in triplicate, for 72 h at 37 degrees C. Subsamples were collected after 0, 24, 48, and 72 h of incubation for culture and enumeration of bacteria. Subsamples of bedding were also tested for pH, total C content (%), and total N content (%). If bacterial growth occurred, peak levels were typically achieved within 24 h. Digested manure solids promoted the greatest amounts of growth of K. pneumoniae, followed by RS and then SH, whereas CS promoted the least. There would seem to be a tradeoff in selecting SH as a bedding material, because it supported moderate growth of K. pneumoniae but caused a rapid decline in the numbers of E. faecium. However, RS, CS, and DS each only supported relatively small amounts of growth of E. faecium, so the benefit of SH relative to other bedding materials is limited. High bedding pH may partially explain why some bedding materials supported growth of E. faecium (e.g., DS and RS). Both high bedding pH (e.g., as for DS or RS) and high total C (%) content (e.g., as for DS and SH) may partially explain why some bedding materials supported growth of K. pneumoniae.

  7. Exploring the Different Trajectories of Analytical Thinking Ability Factors: An Application of the Second-Order Growth Curve Factor Model

    ERIC Educational Resources Information Center

    Saengprom, Narumon; Erawan, Waraporn; Damrongpanit, Suntonrapot; Sakulku, Jaruwan

    2015-01-01

    The purposes of this study were 1) Compare analytical thinking ability by testing the same sets of students 5 times 2) Develop and verify whether analytical thinking ability of students corresponds to second-order growth curve factors model. Samples were 1,093 eighth-grade students. The results revealed that 1) Analytical thinking ability scores…

  8. Exploring the Different Trajectories of Analytical Thinking Ability Factors: An Application of the Second-Order Growth Curve Factor Model

    ERIC Educational Resources Information Center

    Saengprom, Narumon; Erawan, Waraporn; Damrongpanit, Suntonrapot; Sakulku, Jaruwan

    2015-01-01

    The purposes of this study were 1) Compare analytical thinking ability by testing the same sets of students 5 times 2) Develop and verify whether analytical thinking ability of students corresponds to second-order growth curve factors model. Samples were 1,093 eighth-grade students. The results revealed that 1) Analytical thinking ability scores…

  9. Growth rates of rhizosphere microorganisms depend on competitive abilities of plants for nitrogen

    NASA Astrophysics Data System (ADS)

    Blagodatskaya, Evgenia; Littschwager, Johanna; Lauerer, Marianna; Kuzyakov, Yakov

    2010-05-01

    Rhizosphere - one of the most important ‘hot spots' in soil - is characterized not only by accelerated turnover of microbial biomass and nutrients but also by strong intra- and inter-specific competition. Intra-specific competition occurs between individual plants of the same species, while inter-specific competition can occur both at population level (plant species-specific, microbial species-specific interactions) and at community level (plant - microbial interactions). Such plant - microbial interactions are mainly governed by competition for available N sources, since N is one of the main growth limiting nutrients in natural ecosystems. Functional structure and activity of microbial community in rhizosphere is not uniform and is dependent on quantity and quality of root exudates which are plant specific. It is still unclear how microbial growth and turnover in the rhizosphere are dependent on the features and competitive abilities of plants for N. Depending on C and N availability, acceleration and even retardation of microbial activity and carbon mineralization can be expected in the rhizosphere of plants with high competitive abilities for N. We hypothesized slower microbial growth rates in the rhizosphere of plants with smaller roots, as they usually produce less exudates compared to plants with small shoot-to-root ratio. As the first hypothesis is based solely on C availability, we also expected the greater effect of N availability on microbial growth in rhizosphere of plants with smaller root mass. These hypothesis were tested for two plant species of strawberry: Fragaria vesca L. (native species), and Duchesnea indica (Andrews) Focke (an invasive plant in central Europe) growing in intraspecific and interspecific competition. Microbial biomass and the kinetic parameters of microbial growth in the rhizosphere were estimated by dynamics of CO2 emission from the soil amended with glucose and nutrients. Specific growth rate (µ) of soil microorganisms was

  10. Transient transformation of Podosphaera xanthii by electroporation of conidia.

    PubMed

    Vela-Corcía, David; Romero, Diego; Torés, Juan Antonio; De Vicente, Antonio; Pérez-García, Alejandro

    2015-02-06

    Powdery mildew diseases are a major phytosanitary issue causing important yield and economic losses in agronomic, horticultural and ornamental crops. Powdery mildew fungi are obligate biotrophic parasites unable to grow on culture media, a fact that has significantly limited their genetic manipulation. In this work, we report a protocol based on the electroporation of fungal conidia, for the transient transformation of Podosphaera fusca (synonym Podosphaera xanthii), the main causal agent of cucurbit powdery mildew. To introduce DNA into P. xanthii conidia, we applied two square-wave pulses of 1.7 kV for 1 ms with an interval of 5 s. We tested these conditions with several plasmids bearing as selective markers hygromycin B resistance (hph), carbendazim resistance (TUB2) or GFP (gfp) under control of endogenous regulatory elements from Aspergillus nidulans, Neurospora crassa or P. xanthii to drive their expression. An in planta selection procedure using the MBC fungicide carbendazim permitted the propagation of transformants onto zucchini cotyledons and avoided the phytotoxicity associated with hygromycin B. This is the first report on the transformation of P. xanthii and the transformation of powdery mildew fungi using electroporation. Although the transformants are transient, this represents a feasible method for the genetic manipulation of this important group of plant pathogens.

  11. Preliminary data on growth and enzymatic abilities of soil fungus Humicolopsis cephalosporioides at different incubation temperatures.

    PubMed

    Elíades, Lorena Alejandra; Cabello, Marta N; Pancotto, Verónica; Moretto, Alicia; Rago, María Melisa; Saparrat, Mario C N

    2015-01-01

    Nothofagus pumilio (Poepp & Endl.) Krasser, known as "lenga" is the most important timber wood species in southernmost Patagonia (Argentina). Humicolopsis cephalosporioides Cabral & Marchand is a soil fungus associated with Nothofagus pumilio forests, which has outstanding cellulolytic activity. However, there is no information about the ability of this fungus to use organic substrates other than cellulose, and its ability to produce different enzyme systems, as well as its response to temperature. The aim of this study was to examine the role of H. cephalosporioides in degradation processes in N. pumilio forests in detail by evaluating the in vitro ability of four isolates of this fungus to grow and produce different lytic enzyme systems, and their response to incubation temperature. The ability of the fungi to grow and produce enzyme systems was estimated by inoculating them on agar media with specific substrates, and the cultures were incubated at three temperatures. A differential behavior of each strain in levels of growth and enzyme activity was found according to the medium type and/or incubation temperature. A intra-specific variability was found in H. cephalosporioides. Likewise a possible link between the saprotrophic role of this fungus in N. pumilio forests and the degradation of organic matter under stress conditions, such as those from frosty environments, was also discussed. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  12. Evaluation of soyscreen in an oil-based formulation for UV protection of Beauveria bassiana conidia.

    PubMed

    Behle, Robert W; Compton, David L; Laszlo, Joseph A; Shapiro-Ilan, David I

    2009-10-01

    Soyscreen oil was studied as a formulation ingredient to protect Beauveria bassiana (Balsamo) Vuillemin conidia from UV degradation. Feruloylated soy glycerides, referred to as Soyscreen oil, are biobased UV-absorbing molecules made by combining molecules of soybean oil with ferulic acid. Conidia stored in Soyscreen oil for 28 wk at 25, 30, and 35 degrees C retained viability as well as conidia stored in sunflower oil, demonstrating that Soyscreen did not adversely affect viability with prolonged storage. For samples applied to glass and exposed to simulated sunlight (xenon light), conidia in sunflower oil with or without sunscreens (Soyscreen or oxyl methoxycinnimate) had similar conidia viability after exposure. These oil formulations retained conidia viability better than conidia applied as an aqueous treatment. However, the 10% Soyscreen oil formulation applied to field grown cabbage (Brassica oleracea L.) and bean (Phaseolus vulgaris L.) plants, did not improve residual insecticidal activity compared with aqueous applications of unformulated conidia or two commercial formulations when assayed against Trichoplusia ni (Hübner) larvae. Our results suggest that the oil applications lose UV protection because the oil was absorbed by the leaf. This conclusion was supported in subsequent laboratory exposures of conidia in oil-based formulations with UV screens applied to cabbage leaves or balsa wood, which lost protection as measured by decreased viability of conidia when exposed to simulated sunlight. As a result, additional formulation techniques such as encapsulation to prevent separation of the protective oil from the conidia may be required to extend protection when oil formulations are applied in the field.

  13. Two Novel Genes Induced by Hard-Surface Contact of Colletotrichum gloeosporioides Conidia

    PubMed Central

    Kim, Yeon-Ki; Liu, Zhi-Mei; Li, Daoxin; Kolattukudy, Pappachan E.

    2000-01-01

    Germinating conidia of many phytopathogenic fungi must differentiate into an infection structure called the appressorium in order to penetrate into their hosts. This differentiation is known to require contact with a hard surface. However, the molecular basis for this requirement is not known. Induction of this differentiation in the avocado pathogen, Colletotrichum gloeosporioides, by chemical signals such as the host's surface wax or the fruit-ripening hormone, ethylene, requires contact of the conidia with a hard surface for about 2 h. To study molecular events triggered by hard-surface contact, we isolated several genes expressed during the early stage of hard-surface treatment by a differential-display method. The genes that encode Colletotrichum hard-surface induced proteins are designated chip genes. In this study, we report the characterization of CHIP2 and CHIP3 genes that would encode proteins with molecular masses of 65 and 64 kDa, respectively, that have no homology to any known proteins. The CHIP2 product would contain a putative nuclear localization signal, a leucine zipper motif, and a heptad repeat region which might dimerize into coiled-coil structure. The CHIP3 product would be a nine-transmembrane-domain-containing protein. RNA blots showed that CHIP2 and CHIP3 are induced by a 2-h hard-surface contact. However, disruption of these genes did not affect the appressorium-forming ability and did not cause a significant decrease in virulence on avocado or tomato fruits suggesting that C. gloeosporioides might have genes functionally redundant to CHIP2 and CHIP3 or that these genes induced by hard-surface contact control processes not directly involved in pathogenesis. PMID:10940006

  14. Microencapsuling aerial conidia of Trichoderma harzianum through spray drying at elevated temperatures

    USDA-ARS?s Scientific Manuscript database

    Trichoderma conidia are mostly produced by solid fermentation systems. Inoculum is produced by liquid culturing, and then transferred to solid substrate for aerial conidial production. Aerial conidia of T. harzianum are hydrophilic in nature, and it is difficult to separate them from the solid subst...

  15. Novel technique for quantifying adhesion of Metarhizium anisopliae conidia to the tick cuticle.

    PubMed

    Ment, Dana; Gindin, Galina; Rot, Asael; Soroker, Victoria; Glazer, Itamar; Barel, Shimon; Samish, Michael

    2010-06-01

    The present study describes an accurate quantitative method for quantifying the adherence of conidia to the arthropod cuticle and the dynamics of conidial germination on the host. The method was developed using conidia of Metarhizium anisopliae var. anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae) and engorged Rhipicephalus annulatus (Say) (Arachnida: Ixodidae) females and was also verified for M. anisopliae var. acridum Driver et Milner (Hypocreales: Clavicipitaceae) and Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) larvae. This novel method is based on using an organic solvent (dichloromethane [DCM]) to remove the adhered conidia from the tick cuticle, suspending the conidia in a detergent solution, and then counting them using a hemocytometer. To confirm the efficacy of the method, scanning electron microscopy (SEM) was used to observe the conidial adherence to and removal from the tick cuticle. As the concentration of conidia in the suspension increased, there were correlating increases in both the number of conidia adhering to engorged female R. annulatus and tick mortality. However, no correlation was observed between a tick's susceptibility to fungal infection and the amount of adhered conidia. These findings support the commonly accepted understanding of the nature of the adhesion process. The mechanism enabling the removal of the adhered conidia from the host cuticle is discussed.

  16. Fate of conidia of Paracoccidioides brasiliensis after ingestion by resident macrophages or cytokine-treated macrophages.

    PubMed Central

    Cano, L E; Brummer, E; Stevens, D A; Restrepo, A

    1992-01-01

    Conidia ingested by resident macrophages had an enhanced percentage of transformation to yeast cells compared with those in culture medium without macrophages. The yeast cells subsequently grew intracellularly by budding. Macrophages treated with cytokines from antigen-stimulated spleen cells from immunized mice significantly inhibited transformation of ingested conidia. PMID:1563800

  17. Fate of conidia of Paracoccidioides brasiliensis after ingestion by resident macrophages or cytokine-treated macrophages.

    PubMed

    Cano, L E; Brummer, E; Stevens, D A; Restrepo, A

    1992-05-01

    Conidia ingested by resident macrophages had an enhanced percentage of transformation to yeast cells compared with those in culture medium without macrophages. The yeast cells subsequently grew intracellularly by budding. Macrophages treated with cytokines from antigen-stimulated spleen cells from immunized mice significantly inhibited transformation of ingested conidia.

  18. Analysis of the abilities of endophytic bacteria associated with banana tree roots to promote plant growth.

    PubMed

    Andrade, Leandro Fernandes; de Souza, Gleika Larisse Oliveira Dorasio; Nietsche, Silvia; Xavier, Adelica Aparecida; Costa, Marcia Regina; Cardoso, Acleide Maria Santos; Pereira, Marlon Cristian Toledo; Pereira, Débora Francine Gomes Silva

    2014-01-01

    A total of 40 endophytic bacterial isolates obtained from banana tree roots were characterized for their biotechnological potential for promoting banana tree growth. All isolates had at least one positive feature. Twenty isolates were likely diazotrophs and formed pellicles in nitrogen-free culture medium, and 67% of these isolates belonged to the genus Bacillus sp. The isolates EB-04, EB-169, EB-64, and EB-144 had N fixation abilities as measured by the Kjeldahl method and by an acetylene reduction activity assay. Among the 40 isolates, 37.5% were capable of solubilizing inorganic phosphate and the isolates EB-47 and EB-64 showed the highest solubilization capacity. The isolate EB-53 (Lysinibacillus sp.) had a high solubilization index, whereas 73% of the isolates had low solubilization indices. The synthesis of indole-3-acetic acid (IAA) in the presence of L-tryptophan was detected in 40% of the isolates. The isolate EB-40 (Bacillus sp.) produced the highest amount of IAA (47.88 μg/ml) in medium supplemented with L-tryptophan and was able to synthesize IAA in the absence of L-tryptophan. The isolates EB-126 (Bacillus subtilis) and EB-47 (Bacillus sp.) were able to simultaneously fix nitrogen, solubilize phosphate and produce IAA in vitro. The results of this study demonstrated that the isolates analyzed here had diverse abilities and all have the potential to be used as growth-promoting microbial inoculants for banana trees.

  19. Cell wall alpha1-3glucans induce the aggregation of germinating conidia of Aspergillus fumigatus.

    PubMed

    Fontaine, Thierry; Beauvais, Anne; Loussert, Céline; Thevenard, Benoît; Fulgsang, Claus C; Ohno, Naohito; Clavaud, Cécile; Prevost, Marie-Christine; Latgé, Jean-Paul

    2010-08-01

    The germination of Aspergillus fumigatus conidia can be divided into four stages: breaking of dormancy, isotropic swelling, establishment of cell polarity, and formation of a germ tube. Swelling of conidia is associated in liquid medium with a multi-cellular aggregation that produced large clumps of conidia. Conidial aggregation can be specifically prevented by the addition of alpha1-3glucanase. Swollen conidia specifically adhere to insoluble alpha1-3glucan chains. Electron microscopy studies showed that cell wall alpha1-3glucan chains became exposed at the cell surface during the swelling. These results demonstrate that cell wall alpha1-3glucans play an essential role in the aggregation between swollen conidia. Experiments with alpha1-3glucan coated latex beads show that alpha1-3glucan chains interacted between them without the requirement of any other cell wall component suggesting that biophysical properties of alpha1-3glucans are solely responsible for conidial aggregation.

  20. Inherent Variability of Growth Media Impacts the Ability of Salmonella Typhimurium to Interact with Host Cells.

    PubMed

    Sridhar, Sushmita; Steele-Mortimer, Olivia

    2016-01-01

    Efficient invasion of non-phagocytic cells, such as intestinal epithelial cells, by Salmonella Typhimurium is dependent on the Salmonella Pathogenicity Island 1 (SPI-1)-encoded Type Three Secretion System. The environmental cues involved in SPI-1 induction are not well understood. In vitro, various conditions are used to induce SPI-1 and the invasive phenotype. Although lysogeny broth (LB) is widely used, multiple formulations exist, and variation can arise due to intrinsic differences in complex components. Minimal media are also susceptible to variation. Still, the impact of these inconsistencies on Salmonella virulence gene expression has not been well studied. The goal of this project is to identify growth conditions in LB and minimal medium that affect SPI-1 induction in vitro using both whole population and single cell analysis. Here we show, using a fluorescent reporter of the SPI-1 gene prgH, that growth of Salmonella in LB yields variable induction. Deliberate modification of media components can influence the invasive profile. Finally, we demonstrate that changes in SPI-1 inducing conditions can affect the ability of Salmonella to replicate intracellularly. These data indicate that the specific media growth conditions impact how the bacteria interact with host cells.

  1. Inherent Variability of Growth Media Impacts the Ability of Salmonella Typhimurium to Interact with Host Cells

    PubMed Central

    Sridhar, Sushmita; Steele-Mortimer, Olivia

    2016-01-01

    Efficient invasion of non-phagocytic cells, such as intestinal epithelial cells, by Salmonella Typhimurium is dependent on the Salmonella Pathogenicity Island 1 (SPI-1)-encoded Type Three Secretion System. The environmental cues involved in SPI-1 induction are not well understood. In vitro, various conditions are used to induce SPI-1 and the invasive phenotype. Although lysogeny broth (LB) is widely used, multiple formulations exist, and variation can arise due to intrinsic differences in complex components. Minimal media are also susceptible to variation. Still, the impact of these inconsistencies on Salmonella virulence gene expression has not been well studied. The goal of this project is to identify growth conditions in LB and minimal medium that affect SPI-1 induction in vitro using both whole population and single cell analysis. Here we show, using a fluorescent reporter of the SPI-1 gene prgH, that growth of Salmonella in LB yields variable induction. Deliberate modification of media components can influence the invasive profile. Finally, we demonstrate that changes in SPI-1 inducing conditions can affect the ability of Salmonella to replicate intracellularly. These data indicate that the specific media growth conditions impact how the bacteria interact with host cells. PMID:27280414

  2. Dark Period Following UV-C Treatment Enhances Killing of Botrytis cinerea Conidia and Controls Gray Mold of Strawberries.

    PubMed

    Janisiewicz, Wojciech J; Takeda, Fumiomi; Glenn, D Michael; Camp, Mary J; Jurick, Wayne M

    2016-04-01

    Strawberries are available throughout the year either from production in the field or from high and low tunnel culture. Diversity of production conditions results in new challenges in controlling diseases before and after harvest. Fungicides have traditionally been used to control these diseases; however, their limitations necessitate a search for new approaches. We found that UV-C irradiation of Botrytis cinerea, a major pathogen of strawberry, can effectively kill this fungus if a dark period follows the treatment. The inclusion of a 4-h dark period resulted in almost complete kill of B. cinerea conidia on agar media at a dose of 12.36 J/m2. The UV-C dose did not cause a reduction in photosynthesis in strawberry leaves or discoloration of sepals, even after exposing plants repeatedly (twice a week) for 7 weeks. Although irradiation of dry conidia of B. cinerea with this dose resulted in some survival, the conidia were not infective and not able to cause decay even when inoculated onto a highly susceptible mature apple fruit. Irradiation of strawberry pollen at 12.36 J/m2 did not affect pollen germination, tube growth and length in vitro, or germination and tube growth in the style of hand-pollinated emasculated strawberry flowers. No negative effect of the UV-C treatment was observed on fruit yield and quality in high tunnel culture. In the fruit and flower petal inoculation tests, the UV-C treatment was highly effective in reducing fruit decay and petal infection. This UV-C treatment with an exposure time of 60 s may be useful in controlling gray mold in tunnel production of strawberries and may also have the potential for use in intensive field and indoor production of other fruits and vegetables providing that a 4-h dark period follows the irradiation.

  3. Transcription profile of Trichophyton rubrum conidia grown on keratin reveals the induction of an adhesin-like protein gene with a tandem repeat pattern.

    PubMed

    Bitencourt, Tamires Aparecida; Macedo, Claudia; Franco, Matheus Eloy; Assis, Amanda Freire; Komoto, Tatiana Takahasi; Stehling, Eliana Guedes; Beleboni, Rene Oliveira; Malavazi, Iran; Marins, Mozart; Fachin, Ana Lúcia

    2016-03-18

    Trichophyton rubrum is a cosmopolitan filamentous fungus that can infect human keratinized tissue (skin, nails and, rarely, hair) and is the major agent of all chronic and recurrent dermatophytoses. The dermatophyte infection process is initiated through the release of arthroconidial adhesin, which binds to the host stratum corneum. The conidia then germinate, and fungal hyphae invade keratinized skin structures through the secretion of proteases. Although arthroconidia play a central role in pathogenesis, little is known about the dormancy and germination of T. rubrum conidia and the initiation of infection. The objective of this study was to evaluate the transcriptional gene expression profile of T. rubrum conidia during growth on keratin- or elastin-containing medium, mimicking superficial and deep dermatophytosis, respectively. A transcriptional profiling analysis was conducted using a custom oligonucleotide-based microarray by comparing T. rubrum conidia grown on elastin and keratin substrates. This comparison shows differences according to protein source used, but consisted of a very small set of genes, which could be attributed to the quiescent status of conidia. The modulated genes were related to the dormancy, survival and germination of conidia, including genes involved in the respiratory chain, signal transduction and lipid metabolism. However, an induction of a great number of proteases occurred when T. rubrum was grown in the presence of keratin such as the subtilisin family of proteases (Sub 1 and Sub 3) and leucine aminopeptidase (Lap 1 and Lap 2). Interestingly, keratin also promoted the up-regulation of a gene encoding an adhesin-like protein with a tandem repeat sequence. In silico analysis showed that the protein contains a domain related to adhesin that may play a role in host-pathogen interactions. The expression of this adhesin-like gene was also induced during the co-culture of T. rubrum with a human keratinocyte cell line, confirming its

  4. Growth ability of Gram negative bacteria in free-living amoebae.

    PubMed

    Zeybek, Zuhal; Binay, Ali Rıza

    2014-11-01

    When bacteria and free-living amoebae (FLAs) live both in natural waters and man-made aquatic systems, they constantly interact with each other. Some bacteria can survive and grow within FLAs. Therefore, it has recently been thought that FLAs play an important role in spreading pathogenic bacteria in aquatic systems. In this study we investigated the intracellular growing ability of 7 different Gram-negative bacteria (Pseudomonas fluorescens, Pseudomonas putida, Pasteurella pneumotropica, Aeromonas salmonicida, Legionella pneumophila serogroup 1, L. pneumophila serogroup 3, L. pneumophila serogroup 6) in four different FLA isolates (A1-A4). Among these, four bacterial isolates (P. fluorescens, P.putida, P.pneumotropica, A.salmonicida) and two free-living amoebae isolates (A3, A4) were isolated from the tap water in our city (Istanbul). It was found that 4 different Gram-negative bacteria could grow in A1, 2 different Gram-negative bacteria could grow in A2, 4 different Gram-negative bacteria could grow in A3, 1 Gram-negative bacterium could grow in A4. In conclusion, we think that this ability of growth could vary according to the characteristics of both bacteria and FLA isolates. Also, other factors such as environmental temperature, bacterial concentration, and extended incubation period may play a role in these interactions. This situation can be clarified with future studies.

  5. Early events in macrophage killing of Aspergillus fumigatus conidia: new flow cytometric viability assay.

    PubMed

    Marr, K A; Koudadoust, M; Black, M; Balajee, S A

    2001-11-01

    Detailed investigations of macrophage phagocytosis and killing of Aspergillus fumigatus conidia have been limited by technical difficulties in quantifying fungal uptake and viability. In order to study early events in cell pathogen ingestion and killing, we developed a new flow cytometry assay that utilizes the fungus-specific viability dye FUN-1. Metabolically active A. fumigatus conidia accumulate orange fluorescence in vacuoles, while dormant or dead conidia stain green. After incubation within THP-1 cells, recovered conidia are costained with propidium iodide (PI) to discriminate between dormant and dead cells. Flow cytometric measurements of FUN-1 metabolism and PI uptake provide indicators of conidial viability, dormancy, and death. Conidial phagocytosis and killing are also assessed by measurement of green and orange FUN-1 fluorescence within the THP-1 cell population. Compared to previously described methods, this assay has less error introduced by membrane permeability changes and serial dilution of filamentous fungal forms. Results suggest that the THP-1 cells kill conidia rapidly (within 6 h) after exposure. Conidia that are preexposed to human serum are ingested and killed more quickly than are nonopsonized conidia.

  6. Effects of 5-Fluorouracil and 5-Fluorodeoxyuridine on Growth and Tumor-Inducing Ability of Agrobacterium tumefaciens

    PubMed Central

    Beardsley, Robert E.; Lipetz, Jacques

    1966-01-01

    Beardsley, Robert E. (Manhattan College, Bronx, N.Y.), and Jacques Lipetz Effects of 5-fluorouracil and 5-fluorodeoxyuridine on growth and tumor-inducing ability of Agrobacterium tumefaciens. J. Bacteriol. 92:346–348. 1966.—Agrobacterium tumefaciens B6, grown in the presence of 5-fluorouracil or 5-fluodeoxyuridine, exhibited a prolonged lag phase. The tumor-inducing ability of bacteria grown in the presence of these compounds was decreased even after exposures as short as 40 min. A positive correlation was found between the growth-inhibitory effects of these compounds and their effects on the tumor-inducing ability of the bacteria. PMID:16562118

  7. CCR4-Not Complex Subunit Not2 Plays Critical Roles in Vegetative Growth, Conidiation and Virulence in Watermelon Fusarium Wilt Pathogen Fusarium oxysporum f. sp. niveum

    PubMed Central

    Dai, Yi; Cao, Zhongye; Huang, Lihong; Liu, Shixia; Shen, Zhihui; Wang, Yuyan; Wang, Hui; Zhang, Huijuan; Li, Dayong; Song, Fengming

    2016-01-01

    CCR4-Not complex is a multifunctional regulator that plays important roles in multiple cellular processes in eukaryotes. In the present study, the biological function of FonNot2, a core subunit of the CCR4-Not complex, was explored in Fusarium oxysporum f. sp. niveum (Fon), the causal agent of watermelon wilt disease. FonNot2 was expressed at higher levels in conidia and germinating conidia and during infection in Fon-inoculated watermelon roots than in mycelia. Targeted disruption of FonNot2 resulted in retarded vegetative growth, reduced conidia production, abnormal conidial morphology, and reduced virulence on watermelon. Scanning electron microscopy observation of infection behaviors and qRT-PCR analysis of in planta fungal growth revealed that the ΔFonNot2 mutant was defective in the ability to penetrate watermelon roots and showed reduced fungal biomass in root and stem of the inoculated plants. Phenotypic and biochemical analyses indicated that the ΔFonNot2 mutant displayed hypersensitivity to cell wall perturbing agents (e.g., Congo Red and Calcofluor White) and oxidative stress (e.g., H2O2 and paraquat), decreased fusaric acid content, and reduced reactive oxygen species (ROS) production during spore germination. Our data demonstrate that FonNot2 plays critical roles in regulating vegetable growth, conidiogenesis and conidia morphology, and virulence on watermelon via modulating cell wall integrity, oxidative stress response, ROS production and FA biosynthesis through the regulation of transcription of genes involved in multiple pathways. PMID:27695445

  8. High Prevalence, Genetic Diversity and Intracellular Growth Ability of Legionella in Hot Spring Environments

    PubMed Central

    Zhou, Haijian; Wang, Huanxin; Xu, Ying; Zhao, Mingqiang; Guan, Hong; Li, Machao; Shao, Zhujun

    2013-01-01

    Background Legionella is the causative agent of Legionnaires' disease, and hot springs are a major source of outbreaks of this disease. It is important from a public health perspective to survey hot spring environments for the presence of Legionella. Methods Prospective surveillance of the extent of Legionella pollution was conducted at three hot spring recreational areas in Beijing, China in 2011. Pulsed-field gel electrophoresis (PFGE) and sequence-based typing (SBT) were used to describe the genetic polymorphism of isolates. The intracellular growth ability of the isolates was determined by interacting with J774 cells and plating the dilutions onto BCYE agar plates. Results Overall, 51.9% of spring water samples showed Legionella-positive, and their concentrations ranged from 1 CFU/liter to 2,218 CFU/liter. The positive rates of Legionella were significantly associated with a free chlorine concentration of ≥0.2 mg/L, urea concentration of ≥0.05 mg/L, total microbial counts of ≥400 CFU/ml and total coliform of ≥3 MPN/L (p<0.01). The Legionella concentrations were significantly associated with sample temperature, pH, total microbial counts and total coliform (p<0.01). Legionella pneumophila was the most frequently isolated species (98.9%), and the isolated serogroups included serogroups 3 (25.3%), 6 (23.4%), 5 (19.2%), 1 (18.5%), 2 (10.2%), 8 (0.4%), 10 (0.8%), 9 (1.9%) and 12 (0.4%). Two hundred and twenty-eight isolates were analyzed by PFGE and 62 different patterns were obtained. Fifty-seven L. pneumophila isolates were selected for SBT analysis and divided into 35 different sequence types with 5 main clonal groups. All the 57 isolates had high intracellular growth ability. Conclusions Our results demonstrated high prevalence and genetic polymorphism of Legionella in springs in Beijing, China, and the SBT and intracellular growth assay results suggested that the Legionella isolates of hot spring environments were pathogenic. Improved control and

  9. Differential Pathogenicity of Metarhizium Blastospores and Conidia Against Larvae of Three Mosquito Species.

    PubMed

    Alkhaibari, A M; Carolino, A T; Bull, J C; Samuels, R I; Butt, T M

    2017-05-01

    Biorational insecticides are being increasingly used in integrated pest management programs. In laboratory bioassays, the pathogenicity of blastospores and conidia of the entomopathogenic fungus Metarhizium brunneum ARSEF 4556 was evaluated against larvae of three mosquito species. Three propagule concentrations (1 × 106, 1 × 107, and 1 × 108 spores ml - 1) were used in the bioassays. Results showed that Aedes aegypti had lower survival rates when exposed to blastospores than when exposed to conidia, whereas the converse was true for Culex quinquefasciatus larvae. Anopheles stephensi larvae survival rates were similar when exposed to blastospores and conidia, except at the higher doses, where blastospores were more virulent. Several assays showed little difference in mortalities when using either 1 × 107 or 1 × 108 spores ml - 1, suggesting a threshold above which no higher control levels or economic benefit would be achieved. When tested at the lowest dose, the LT50 of Cx. quinquefasciatus using blastospores, wet conidia, and dry conidia was 3.2, 1.9, and 4.4 d, respectively. The LT50 of Ae. aegypti using blastospores, wet conidia, and dry conidia was 1.3, 3.3, and 6.2 d, respectively. The LT50 of An. stephensi using blastospores, wet conidia, and dry conidia was 2.0, 1.9, and 2.1 d, respectively. These observations suggest that for optimized control, two different formulations of the fungus may be needed when treating areas where there are mixed populations of Aedes, Anopheles, and Culex. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Yield and cold storage of Trichoderma conidia is influenced by substrate pH and storage temperature.

    PubMed

    Steyaert, Johanna M; Chomic, Anastasia; Nieto-Jacobo, Maria; Mendoza-Mendoza, Artemio; Hay, Amanda J; Braithwaite, Mark; Stewart, Alison

    2017-05-01

    In this study we examined the influence of the ambient pH during morphogenesis on conidial yield of Trichoderma sp. "atroviride B" LU132 and T. hamatum LU593 and storage at low temperatures. The ambient pH of the growth media had a dramatic influence on the level of Trichoderma conidiation and this was dependent on the strain and growth media. On malt-extract agar, LU593 yield decreased with increasing pH (3-6), whereas yield increased with increasing pH for LU132. During solid substrate production the reverse was true for LU132 whereby yield decreased with increasing pH. The germination potential of the conidia decreased significantly over time in cold storage and the rate of decline was a factor of the strain, pH during morphogenesis, growth media, and storage temperature. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Transformation of Epichloë typhina by electroporation of conidia

    PubMed Central

    2011-01-01

    Background Choke, caused by the endophytic fungus Epichloë typhina, is an important disease affecting orchardgrass (Dactylis glomerata L.) seed production in the Willamette Valley. Little is known concerning the conditions necessary for successful infection of orchardgrass by E. typhina. Detection of E. typhina in plants early in the disease cycle can be difficult due to the sparse distribution of hyphae in the plant. Therefore, a sensitive method to detect fungal infection in plants would provide an invaluable tool for elucidating the conditions for establishment of infection in orchardgrass. Utilization of a marker gene, such as the green fluorescent protein (GFP), transformed into Epichloë will facilitate characterization of the initial stages of infection and establishment of the fungus in plants. Findings We have developed a rapid, efficient, and reproducible transformation method using electroporation of germinating Epichloë conidia isolated from infected plants. Conclusions The GFP labelled E. typhina provides a valuable molecular tool to researchers studying conditions and mechanisms involved in the establishment of choke disease in orchardgrass. PMID:21375770

  12. Verruculogen associated with Aspergillus fumigatus hyphae and conidia modifies the electrophysiological properties of human nasal epithelial cells.

    PubMed

    Khoufache, Khaled; Puel, Olivier; Loiseau, Nicolas; Delaforge, Marcel; Rivollet, Danièle; Coste, André; Cordonnier, Catherine; Escudier, Estelle; Botterel, Françoise; Bretagne, Stéphane

    2007-01-23

    The role of Aspergillus fumigatus mycotoxins in the colonization of the respiratory tract by conidia has not been studied extensively, even though patients at risk from invasive aspergillosis frequently exhibit respiratory epithelium damage. In a previous study, we found that filtrates of A. fumigatus cultures can specifically alter the electrophysiological properties of human nasal epithelial cells (HNEC) compared to those of non pathogenic moulds. We fractionated the organic phase of filtrate from 3-day old A. fumigatus cultures using high-performance liquid chromatography. The different fractions were tested for their ability to modify the electrophysiological properties of HNEC in an in vitro primary culture model. The fraction collected between 20 and 30 min mimicked the effects of the whole filtrate, i.e. decrease of transepithelial resistance and increase of potential differences, and contained secondary metabolites such as helvolic acid, fumagillin, and verruculogen. Only verruculogen (10(-8) M) had effects similar to the whole filtrate. We verified that verruculogen was produced by a collection of 67 human, animal, plant and environmental A. fumigatus isolates. Using MS-MS analysis, we found that verruculogen was associated with both mycelium and conidia extracts. Verruculogen is a secondary metabolite that modifies the electrophysiological properties of HNEC. The role of these modifications in the colonization and invasion of the respiratory epithelium by A. fumigatus on first contact with the epithelium remains to be determined.

  13. Verruculogen associated with Aspergillus fumigatus hyphae and conidia modifies the electrophysiological properties of human nasal epithelial cells

    PubMed Central

    Khoufache, Khaled; Puel, Olivier; Loiseau, Nicolas; Delaforge, Marcel; Rivollet, Danièle; Coste, André; Cordonnier, Catherine; Escudier, Estelle; Botterel, Françoise; Bretagne, Stéphane

    2007-01-01

    Background The role of Aspergillus fumigatus mycotoxins in the colonization of the respiratory tract by conidia has not been studied extensively, even though patients at risk from invasive aspergillosis frequently exhibit respiratory epithelium damage. In a previous study, we found that filtrates of A. fumigatus cultures can specifically alter the electrophysiological properties of human nasal epithelial cells (HNEC) compared to those of non pathogenic moulds. Results We fractionated the organic phase of filtrate from 3-day old A. fumigatus cultures using high-performance liquid chromatography. The different fractions were tested for their ability to modify the electrophysiological properties of HNEC in an in vitro primary culture model. The fraction collected between 20 and 30 min mimicked the effects of the whole filtrate, i.e. decrease of transepithelial resistance and increase of potential differences, and contained secondary metabolites such as helvolic acid, fumagillin, and verruculogen. Only verruculogen (10-8 M) had effects similar to the whole filtrate. We verified that verruculogen was produced by a collection of 67 human, animal, plant and environmental A. fumigatus isolates. Using MS-MS analysis, we found that verruculogen was associated with both mycelium and conidia extracts. Conclusion Verruculogen is a secondary metabolite that modifies the electrophysiological properties of HNEC. The role of these modifications in the colonization and invasion of the respiratory epithelium by A. fumigatus on first contact with the epithelium remains to be determined. PMID:17244350

  14. Germination of fungal conidia after exposure to low concentration ozone atmospheres.

    USDA-ARS?s Scientific Manuscript database

    The germinability of conidia of Alternaria alternata, Aspergillus flavus, Aspergillus niger, Penicillium digitatum, Penicillium expansum, or Penicillium italicum was determined periodically during exposure for approximately 100 days to a humid atmosphere of air alone or air containing 150 ppb ozone ...

  15. THE POWER OF THE SMALL: THE EXAMPLE OF Paracoccidioides brasiliensis CONIDIA

    PubMed Central

    RESTREPO, Angela; CANO, Luz Elena; GONZALEZ, Ángel

    2015-01-01

    SUMMARY Research on Paracoccidioides brasiliensis has centered in the yeast cell probably because of the lack of distinctive features in the mycelium. In 1942 and for the first time, lateral conidia were noticed in the fungus' hyphae. Later on, Brazilian, Venezuelan and Argentinean researchers described "aleurias" when the fungus was grown in natural substrates. In 1970 authors became interested in the conidia and were able to obtain them in large numbers and treat them as individual units. Their shape and size were defined and the presence of all the elements of a competent eukaryotic cell were demonstrated. Conidia exhibited thermal dimorphism and, additionally, when given intranasally to BALB/c male mice, they converted into yeasts in the lungs and produce progressive pulmonary lesions with further dissemination to other organs. Studies on the phagocyte-conidia interaction were revealing and showed that these versatile structures allow a better understanding of the host- P. brasiliensis interactions. PMID:26465363

  16. A staining method for assessing the viability of Esteya vermicola conidia.

    PubMed

    Wang, Yunbo; Thang, NguyenTrong; Li, Zheng; Zhang, Yongan; Li, Jingjie; Xue, Jianjie; Gu, Lijuan; Hong, VuThuy; Mira, Lee; Sung, Changkeun

    2014-07-01

    The viability of conidia of Esteya vermicola, a potentially important biocontrol agent against the pinewood nematode Bursaphelenchus xylophilus, is usually determined by cultivation for 18-48 h in culture medium. As an alternative to this labor-intensive method, we have developed a rapid, simple, and low-cost staining method for assessing E vermicola conidia survival rates. A mixture of neutral red and methylene blue was found to be the most optimal among several stains that also included safranin O and Janus green B. This mixture stained nonviable conidia blue, in contrast to viable conidia, which were stained red in the cytoplasm and blue in the cell wall. This method may be particularly useful for traditional research laboratories, as it provides rapid results using common, relatively inexpensive laboratory equipment.

  17. Evaluation of plant growth promoting and colonization ability of endophytic diazotrophs from deep water rice.

    PubMed

    Verma, S C; Ladha, J K; Tripathi, A K

    2001-10-04

    A study of the diversity of endophytic bacteria present in seeds of a deepwater rice variety revealed the presence of seven types of BOX-PCR fingerprints. In order to evaluate the plant growth promoting potential the presence of nitrogenase, indole acetic acid production and mineral phosphate solubilization were estimated in the representative BOX-PCR types. The seven representatives of BOX-PCR types produced indole acetic acid, reduced acetylene and showed specific immunological cross-reaction with anti-dinitrogenase reductase antibody. Only four types showed mineral phosphate solubilizing ability. Comparison of cellulase and pectinase activities showed differences among different BOX-PCR types. PCR fingerprinting data showed that one strain isolated from the surface sterilized seeds as well as the aerial parts of the seedlings of rice variety showed low cellulase and pectinase but relatively high ARA. On the basis of 16S rDNA nucleotide sequence and BIOLOG system of bacterial identification, this strain was identified as Pantoea agglomerans. For studying the endophytic colonization this strain was genetically tagged with the reporter gene, gusA. Histochemical analysis of the seedling grown in hydroponics showed that the tagged strain colonized the root surface, root hairs, root cap, points of lateral root emergence, root cortex and the stelar region. Treatment of the roots with 2,4-D produced short thickened lateral roots which showed better colonization by P. agglomerans.

  18. Transcriptomic analysis of the exit from dormancy of Aspergillus fumigatus conidia

    PubMed Central

    Lamarre, Claude; Sokol, Sergueï; Debeaupuis, Jean-Paul; Henry, Christine; Lacroix, Céline; Glaser, Philippe; Coppée, Jean-Yves; François, Jean-Marie; Latgé, Jean-Paul

    2008-01-01

    Background Establishment of aspergillosis is depending upon the exit from dormancy and germination of the conidia of Aspergillus fumigatus in the lung. To gain an understanding of the molecular mechanisms underlying the early steps of conidial germination, we undertook a transcriptomic analysis using macroarrays constructed with PCR fragments from > 3,000 genes (around one third of the annotated A. fumigatus genome). Results Major results of this analysis are the following: (i) conidia stored pre-packaged mRNAs transcripts (27% of genes have transcripts in the resting conidia; (ii) incubation at 37°C in a nutritive medium induced up- and down-regulation of genes: 19% of the total number of genes deposited on the array were up-regulated whereas 22% of the genes with pre-packaged mRNA in the resting conidia were down-regulated; (iii) most modifications were seen during the first 30 min of germination whereas very little modification of gene expression occurred during the following hour; (iv) one-year old conidia and one-week old conidia behaved similarly at transcriptional level. Conclusion Transcriptomic data indicate that the exit from dormancy is associated with a shift from a fermentative metabolism to a respiratory metabolism as well as a trend toward immediate protein synthesis. PMID:18796135

  19. Interaction between Paracoccidioides brasiliensis conidia and the coagulation system: involvement of fibrinogen

    PubMed Central

    Tamayo, Diana; Hernández, Orville; Muñoz-Cadavid, Cesar; Cano, Luz Elena; González, Angel

    2013-01-01

    The infectious process starts with an initial contact between pathogen and host. We have previously demonstrated that Paracoccidioides brasiliensis conidia interact with plasma proteins including fibrinogen, which is considered the major component of the coagulation system. In this study, we evaluated the in vitro capacity of P. brasiliensis conidia to aggregate with plasma proteins and compounds involved in the coagulation system. We assessed the aggregation of P. brasiliensis conidia after incubation with human serum or plasma in the presence or absence of anticoagulants, extracellular matrix (ECM) proteins, metabolic and protein inhibitors, monosaccharides and other compounds. Additionally, prothrombin and partial thromboplastin times were determined after the interaction of P. brasiliensis conidia with human plasma. ECM proteins, monosaccharides and human plasma significantly induced P. brasiliensis conidial aggregation; however, anticoagulants and metabolic and protein inhibitors diminished the aggregation process. The extrinsic coagulation pathway was not affected by the interaction between P. brasiliensis conidia and plasma proteins, while the intrinsic pathway was markedly altered. These results indicate that P. brasiliensis conidia interact with proteins involved in the coagulation system. This interaction may play an important role in the initial inflammatory response, as well as fungal disease progression caused by P. brasiliensis dissemination. PMID:23827999

  20. Interaction between Paracoccidioides brasiliensis conidia and the coagulation system: involvement of fibrinogen.

    PubMed

    Tamayo, Diana; Hernández, Orville; Muñoz-Cadavid, Cesar; Cano, Luz Elena; González, Angel

    2013-06-01

    The infectious process starts with an initial contact between pathogen and host. We have previously demonstrated that Paracoccidioides brasiliensis conidia interact with plasma proteins including fibrinogen, which is considered the major component of the coagulation system. In this study, we evaluated the in vitro capacity of P. brasiliensis conidia to aggregate with plasma proteins and compounds involved in the coagulation system. We assessed the aggregation of P. brasiliensis conidia after incubation with human serum or plasma in the presence or absence of anticoagulants, extracellular matrix (ECM) proteins, metabolic and protein inhibitors, monosaccharides and other compounds. Additionally, prothrombin and partial thromboplastin times were determined after the interaction of P. brasiliensis conidia with human plasma. ECM proteins, monosaccharides and human plasma significantly induced P. brasiliensis conidial aggregation; however, anticoagulants and metabolic and protein inhibitors diminished the aggregation process. The extrinsic coagulation pathway was not affected by the interaction between P. brasiliensis conidia and plasma proteins, while the intrinsic pathway was markedly altered. These results indicate that P. brasiliensis conidia interact with proteins involved in the coagulation system. This interaction may play an important role in the initial inflammatory response, as well as fungal disease progression caused by P. brasiliensis dissemination.

  1. Melanin is required for the formation of the multi-cellular conidia in the endophytic fungus Pestalotiopsis microspora.

    PubMed

    Yu, Xi; Huo, Liang; Liu, Heng; Chen, Longfei; Wang, Yu; Zhu, Xudong

    2015-10-01

    Melanin plays an important role in regulating various biological processes in many fungi. However, its biological role in conidiation remains largely elusive. We report here that conidia production, morphogenesis, integrity, germination and their viability in Pestalotiopsis microspora require the polyketide-derived melanin. A polyketide synthase gene, pks1, was identified and demonstrated responsible for melanin biosynthesis in this fungus. A targeted deletion mutant strain Δpks1 displayed a defect in pigmentation of conidia and had an albino colonial phenotype. Interestingly, Δpks1 produced approximately 6-fold as many conidia as the wild type did, suggesting a negative modulation of melanin on conidia production in this fungus. Moreover, the conidia failed to develop into the normal five-cell morphology, rather the three main-body cells separated via constriction at the original septum position to generate three independent mutant conidia. This result suggests a novel role of melanin in the formation of the multi-cellular conidia. Germ tubes could develop from the three different types of mutant conidia and kept elongating, despite a significantly lower germination rate was observed for them. Still more, the unpigmented conidia became permeable to Calcofluor White and DAPI, suggesting the integrity of the conidia was impaired. Deliberate inhibition of melanin biosynthesis by a specific inhibitor, tricyclazole, led to a similar phenotypes. This work demonstrates a new function of fungal melanin in conidial development.

  2. Influence of mechanical stress and surface interaction on the aggregation of Aspergillus niger conidia.

    PubMed

    Grimm, L H; Kelly, S; Völkerding, I I; Krull, R; Hempel, D C

    2005-12-30

    Productivity of fungal cultures is closely linked with their morphologic development. Morphogenesis of coagulating filamentous fungi, like Aspergillus niger, starts with aggregation of conidia, also denominated as spores. Several parameters are presumed to control this event, but little is known about their mode of action. Rational process optimization requires models that mirror the underlying reaction mechanisms. An approach in this regard is suggested and supported by experimental data. Aggregation kinetics was examined for the first 15 h of cultivation under different cultivation conditions. Mechanical stress was considered as well as pH-dependent surface interaction. Deliberations were based on a two-step aggregation mechanism. The first aggregation step is only affected by the pH-value, not by the fluid dynamic conditions in the bioreactor. The second aggregation step, in contrast, depends on the pH-value as well as on agitation and aeration induced power input. For the given experimental set-up, agitation had much more influence than aeration. In addition, hyphal growth rate was determined to be the driving force for the second aggregation step.

  3. Solid substrate production of Epicoccum nigrum conidia for biological control of brown rot on stone fruits.

    PubMed

    Larena, I; De Cal, A; Melgarejo, P

    2004-07-15

    Production of conidia of Epicoccum nigrum, a biocontrol agent of the fungal pathogen Monilinia laxa, was tested in liquid- and solid-state fermentation. Liquid fermentation was conducted in 250 ml Erlenmeyer flasks containing 50 ml of a mineral medium (containing per litre: 20 g lactose, 10 g NO3K, 1 g K2HPO4, 0.5 g MgSO4.7H2O, and 1 ml of a minor-element solution), inoculated with 2 x 10(5) E. nigrum conidia ml(-1), and incubated at 20-25 degrees C and 150 rpm for 7 days. Solid-state fermentation was carried out in specially designed plastic bags (600 cm3) (VALMIC) containing either 50 g of peat/vermiculite (1:1, w/w), or 50 g of peat/vermiculite/lentil meal (1:1:1, w/w/w) with 40% (v/w) initial moisture content. Substrate was inoculated with a conidial suspension of E. nigrum to give 10(5) conidia g(-1) substrate, and bags were incubated at 20-25 degrees C for 7 days in darkness. The amount of conidia of E. nigrum obtained in solid-state fermentation with substrate based on peat/vermiculite/lentil meal was 10-fold higher than with substrate based on peat/vermiculite or in liquid fermentation. Conidial production under these conditions was maintained in the range of 10(8) conidia g(-1) substrate from 10 to 150 days after inoculation. Germinability of these conidia was >90%. Addition of other nutrients than lentil meal to peat/vermiculite did not enhance production of conidia. Presence of peat in the substrate was necessary for good conidia production, but change in the kind of peat or vermiculite did not improve conidial production. Conidial production was similar when the substrate was inoculated with 10(5), 10(6) or 10(7) conidia g(-1) dry substrate. Incubation of bags in light conditions did not enhance conidial production. Fresh conidia produced in this solid-state fermentation system reduced the incidence and lesion diameter induced by M. laxa on peaches.

  4. Simulated warming differentially affects the growth and competitive ability of Centaurea maculosa populations from home and introduced ranges.

    PubMed

    He, Wei-Ming; Li, Jing-Ji; Peng, Pei-Hao

    2012-01-01

    Climate warming may drive invasions by exotic plants, thereby raising concerns over the risks of invasive plants. However, little is known about how climate warming influences the growth and competitive ability of exotic plants from their home and introduced ranges. We conducted a common garden experiment with an invasive plant Centaurea maculosa and a native plant Poa pratensis, in which a mixture of sand and vermiculite was used as a neutral medium, and contrasted the total biomass, competitive effects, and competitive responses of C. maculosa populations from Europe (home range) and North America (introduced range) under two different temperatures. The warming-induced inhibitory effects on the growth of C. maculosa alone were stronger in Europe than in North America. The competitive ability of C. maculosa plants from North America was greater than that of plants from Europe under the ambient condition whereas this competitive ability followed the opposite direction under the warming condition, suggesting that warming may enable European C. maculosa to be more invasive. Across two continents, warming treatment increased the competitive advantage instead of the growth advantage of C. maculosa, suggesting that climate warming may facilitate C. maculosa invasions through altering competitive outcomes between C. maculosa and its neighbors. Additionally, the growth response of C. maculosa to warming could predict its ability to avoid being suppressed by its neighbors.

  5. Simulated Warming Differentially Affects the Growth and Competitive Ability of Centaurea maculosa Populations from Home and Introduced Ranges

    PubMed Central

    He, Wei-Ming; Li, Jing-Ji; Peng, Pei-Hao

    2012-01-01

    Climate warming may drive invasions by exotic plants, thereby raising concerns over the risks of invasive plants. However, little is known about how climate warming influences the growth and competitive ability of exotic plants from their home and introduced ranges. We conducted a common garden experiment with an invasive plant Centaurea maculosa and a native plant Poa pratensis, in which a mixture of sand and vermiculite was used as a neutral medium, and contrasted the total biomass, competitive effects, and competitive responses of C. maculosa populations from Europe (home range) and North America (introduced range) under two different temperatures. The warming-induced inhibitory effects on the growth of C. maculosa alone were stronger in Europe than in North America. The competitive ability of C. maculosa plants from North America was greater than that of plants from Europe under the ambient condition whereas this competitive ability followed the opposite direction under the warming condition, suggesting that warming may enable European C. maculosa to be more invasive. Across two continents, warming treatment increased the competitive advantage instead of the growth advantage of C. maculosa, suggesting that climate warming may facilitate C. maculosa invasions through altering competitive outcomes between C. maculosa and its neighbors. Additionally, the growth response of C. maculosa to warming could predict its ability to avoid being suppressed by its neighbors. PMID:22303485

  6. Effects of Stachybotrys chartarum (atra) conidia and isolated toxin on lung surfactant production and homeostasis.

    PubMed

    Mason, C D; Rand, T G; Oulton, M; MacDonald, J M; Scott, J E

    1998-01-01

    This study evaluated the effects of Stachybotrys chartarum conidia and a trichothecene, isosatratoxin-F, on choline incorporation into DSPC by fetal rabbit alveolar type II cells and on alveolar surfactant subtypes in mice. Exposure of fetal rabbit type II cells to S. chartarum conidia at concentrations of 10(3) to 10(6) conidia ml(-1) significantly depressed [3H] choline incorporation after 24 h of exposure. Exposure of the rabbit cells to 10(5) to 10(6) conidia ml(-1) also resulted in significantly depressed [3H] choline uptake after 48 h. Additionally, fetal rabbit alveolar type II cells exposed to isosatratoxin-F in concentrations ranging from 10(-9) to 10(-4) M showed a significant reduction in [3H] choline incorporation into DSPC. Alveolar surfactant phospholipid concentrations in the different metabolic subfractions of lung lavage fluid of mice intratracheally exposed to either 50 microl of 10(7) ml(-1) S. chartarum conidia or 50 microl 10(-7) M isosatratoxin-F showed some significant changes at 12, 24, 48, and 72 h post-exposure, compared to the surfactant subfractions of control mice which were either untreated, exposed to saline or to 50 microl of 10(-7) ml(-1) Cladosporium cladosporioides conidia. In both the S. chartarum- and the isosatratoxin-F-treated mice, exposure significantly increased P10, P100, and S100 phospholipid concentrations, while the P60 phospholipid concentrations were depressed. In contrast, C. cladosporioides-treated mice showed only one significant change in subfraction phospholipid concentration: P60 was depressed at 48 h post-exposure. These results reveal that alveolar type II cells are sensitive to exposure to S. chartarum conidia and to isosatratoxin F. Sensitivity is manifest by alterations in the normal metabolic processing of alveolar surfactant. In exposed mice, this effect appears to involve a significant increase in newly secreted surfactant and an accumulation of the used surfactant forms.

  7. [Identification of genes associated with germination of conidia to form mycelia in the fungus Paracoccidioides brasiliensis].

    PubMed

    García, Ana María; Hernández, Orville; Aristizábal, Beatriz H; Cano, Luz Elena; Restrepo, Angela; McEwen, Juan G

    2009-09-01

    Paracoccidioides brasiliensis is a thermo-dimorphic fungus. At room temperature it grows as a mold that produces conidia, whereas in the vertebrate host it grows as a multiple-budding yeast. The molecular mechanisms involved in the germination from the conidia to the mycelia process remain unknown. The kinetics of conidia to mycelia germination process were studied in the dimorphic fungus P. brasiliensis. Gene expression during this process was evaluated by construction and analysis of an EST library. For the germination kinetics study, P. brasiliensis conidia were isolated as single cell units. Then, they were cultured at 18 degrees C in BHI (brain-heart infusion) broth for 24, 48, 72 and 96 hr. After each perion, they were examined by light microscopy. From conidia harvested at 96 hr, an EST library was constructed; at this stage the gene expression was presumed to be maximal for the germination process. During the conidia to the mycelia developmental process, the following germination rates were observed: at 24 hr, 11.7+/-1.2%; at 48 hr, 30+/-0.6%; at 72 hr, 43+/-1.3%; and at 96 hr, 66+/-2.4%. At the 96 hour stage, an EST library was constructed. It consisted of 129 sequences grouped in 4 contigs and 7 singlets for a total of 11 possible genes. Eight of the sequences had not been described previously in other EST libraries of this fungus. New genes were identified that were expressed during the conidia to the mycelia germination process and may represent genes specific to the germination process.

  8. Plasma metabolite levels predict bird growth rates: A field test of model predictive ability.

    PubMed

    Albano, Noelia; Masero, José A; Villegas, Auxiliadora; Abad-Gómez, José María; Sánchez-Guzmán, Juan M

    2011-09-01

    Bird growth rates are usually derived from nonlinear relationships between age and some morphological structure, but this procedure may be limited by several factors. To date, nothing is known about the capacity of plasma metabolite profiling to predict chick growth rates. Based on laboratory-trials, we here develop predictive logistic models of body mass, and tarsus and wing length growth rates in Gull-billed Tern Gelochelidon nilotica chicks from measurements of plasma metabolite levels at different developmental stages. The predictive model obtained during the fastest growth period (at the age of 12 days) explained 65-68% of the chicks' growth rates, with fasting triglyceride level explaining most of the variation in growth rate. At the end of pre-fledging period, β-hydroxybutyrate level was also a good predictor of growth rates. Finally, we carried out a field test to check the predictive capacity of the models in two colonies of wild Gull-billed Tern, comparing field-measured and model-predicted growth rates between groups. Both, measured and predicted growth rates, matched statistically. Plasma metabolite levels can thus be applied in comparative studies of chick growth rates when semi-precocial birds can be captured only once.

  9. [Influence of different drying temperatures for solid substrate after fermentation on conidia characteristics of the entomopathogenic fungus Beauveria bassiana].

    PubMed

    Li, Zunhua; Lin, Jianwen; Ma, Jincheng; Wu, Di; Zhang, Yongjun

    2008-07-01

    This study was to evaluate the effect of drying temperature for solid substrate after fermentation on conidia characteristics of entomopathogenic fungus Beauveria bassiana. Seven constant or varied temperatures between 28 degrees C and 35 degrees C were designed for drying the solid substrate and the quality of harvested conidia was analyzed. The results showed that the drying treatments at varied temperatures significantly decreased bacterial contamination in the harvested conidia powder. The conidia viability and germination speed were varied with different drying treatments. After drying at 35 degrees C for 5 h, there was no significant difference in viability between the dried and fresh conidia, while the median germination time (9.6 h) of the dried conidia was shortened by 9.3%. The tolerance of conidia to heat and UV radiation was increased by drying treatment. Compared to the drying treatment at a constant temperature at 28 degrees C or 35 degrees C, some varied temperature treatments were in favor of enhancing the stress tolerance of conidia. Drying treatments influenced accumulation of trehalose in harvested conidia, while neither heat resistance nor UV tolerance of conidia was obvious correlation with trehalose level. Optimizing drying temperature could increase the virulence of B. bassiana. After drying at 28 degrees C for 24 h and then 35 degrees C for 2 h or at 35 degrees C for 5 h, the LT(50S) to Myzus persicae at the dose of 370-450 conidia /mm2 were shortened by 10.6 h and 7.5 h, respectively. The results suggested that the drying temperature for post-fermentation solid substrate has an important influence on bacterial contamination in the harvested conidia powder, spore viability, stress tolerance and virulence in B. bassiana.

  10. Molecular and physiological effects of environmental UV radiation on fungal conidia.

    PubMed

    Braga, Gilberto U L; Rangel, Drauzio E N; Fernandes, Éverton K K; Flint, Stephan D; Roberts, Donald W

    2015-08-01

    Conidia are specialized structures produced at the end of the asexual life cycle of most filamentous fungi. They are responsible for fungal dispersal and environmental persistence. In pathogenic species, they are also involved in host recognition and infection. Conidial production, survival, dispersal, germination, pathogenicity and virulence can be strongly influenced by exposure to solar radiation, although its effects are diverse and often species dependent. UV radiation is the most harmful and mutagenic waveband of the solar spectrum. Direct exposure to solar radiation for a few hours can kill conidia of most fungal species. Conidia are killed both by solar UV-A and UV-B radiation. In addition to killing conidia, which limits the size of the fungal population and its dispersion, exposures to sublethal doses of UV radiation can reduce conidial germination speed and virulence. The focus of this review is to provide an overview of the effects of solar radiation on conidia and on the major systems involved in protection from and repair of damage induced by solar UV radiation. The efforts that have been made to obtain strains of fungi of interest such as entomopathogens more tolerant to solar radiation will also be reviewed.

  11. Interaction of Aspergillus fumigatus conidia with Acanthamoeba castellanii parallels macrophage-fungus interactions.

    PubMed

    Van Waeyenberghe, Lieven; Baré, Julie; Pasmans, Frank; Claeys, Myriam; Bert, Wim; Haesebrouck, Freddy; Houf, Kurt; Martel, An

    2013-12-01

    Aspergillus fumigatus and free-living amoebae are common inhabitants of soil. Mechanisms of A. fumigatus to circumvent the amoeba's digestion may facilitate overcoming the vertebrate macrophage defence mechanisms. We performed co-culture experiments using A. fumigatus conidia and the amoeba Acanthamoeba castellanii. Approximately 25% of the amoebae ingested A. fumigatus conidia after 1 h of contact. During intra-amoebal passage, part of the ingested conidia was able to escape the food vacuole and to germinate inside the cytoplasm of A. castellanii. Fungal release into the extra-protozoan environment by exocytosis of conidia or by germination was observed with light and transmission electron microscopy. These processes resulted in structural changes in A. castellanii, leading to amoebal permeabilization without cell lysis. In conclusion, A. castellanii internalizes A. fumigatus conidia, resulting in fungal intracellular germination and subsequent amoebal death. As such, this interaction highly resembles that of A. fumigatus with mammalian and avian macrophages. This suggests that A. fumigatus virulence mechanisms to evade macrophage killing may be acquired by co-evolutionary interactions among A. fumigatus and environmental amoebae.

  12. The physiological effects of multi-walled carbon nanotubes (MWCNTs) on conidia and the development of the entomopathogenic fungus, Metarhizium anisopliae (Metsch.) Sorok.

    PubMed

    Gorczyca, Anna; Kasprowicz, Marek J; Lemek, Tadeusz

    2014-01-01

    The aim of the study was an in vitro evaluation of the effect of MWCNTs on the conidia of two strains of entomopathogenic fungus, Metarhizium anisopliae. The study made use of water suspensions of MWCNTs (concentration ∼ 3 mg·mL(-1)) made from commercial nanotubes and centrifuged. The conidia were placed in contact with nanotubes for 240 h. An assessment of MWCNT influence on conidia was performed after 1, 24, 72 and 240 h and focused on the linear growth of vegetative mycelium derived from these conidia, mycelium sporulation in subcultures and pathogenicity. Using TEM imaging, it was demonstrated that carbon nanotubes are able to damage cell membranes of the examined fungi conidia. However, the absence was noted of a significantly fungistatic effect of both MWCNT suspensions on the examined strains with respect to the physiological features in question. The increase in vegetative mycelium effected by spores after contact with MWCNTs was characterized by a slight modification in relation to the control. There was no strong trend (inhibition - stimulation), in relation to the effect of the tested suspension of carbon nanotubes, on the development of the vegetative mycelium in in vitro culture. Sporulation of the mycelium after completion of the culture only occurred in one case (strain Ma73F and culture of spores after 24-h contact with MWCNTs) significantly more intensely than in the controls. With respect to pathogenicity for test insects compared to the control strain, Ma73F spores grown from the longest contact with nanotubes suspensions performed significantly better. On the basis of the calculated of mycelium index growth rates and the time of death of the test insects (LT50), it was found that the adverse effects of water suspension MWCNTs on the spores of M. anisopliae were applied after a short contact with biological material. This indicates unfavorable physical rather than chemical effects on the tested cell. Over time, nanotube aggregation in water

  13. Protein translation inhibition by Stachybotrys chartarum conidia with and without the mycotoxin containing polysaccharide matrix.

    PubMed

    Karunasena, Enusha; Cooley, J Danny; Straus, Douglas; Straus, David C

    2004-07-01

    Recent studies have correlated the presence of Stachybotrys chartarum in structures with SBS. S. chartarum produces mycotoxins that are thought to produce some of the symptoms reported in sick-building syndrome (SBS). The conidia (spores) produced by Stachybotrys species are not commonly found in the air of buildings that have been found to contain significant interior growth of this organism. This could be due in part to the large size of the Stachybotrys spores, or the organism growing in hidden areas such as wall cavities. However, individuals in buildings with significant Stachybotrys growth frequently display symptoms that may be attributed to exposure to the organism's mycotoxins. In addition, Stachybotrys colonies produce a "slime" or polysaccharide (carbohydrate) matrix that coats the hyphae and the spores. The intent of this project was to determine whether the carbohydrate matrix and the mycotoxins embedded in it could be removed from the spores by repeated washings with either aqueous or organic solvents. The results demonstrated that the process of spore washing removed compounds that were toxic in a protein translation assay as compared to spores that were washed with an organic solution, however a correlation between carbohydrate removal during the washing process and the removal of mycotoxins from the spore surface was not observed. These data demonstrated that mycotoxins are not likely to be found exclusively in the carbohydrate matrix of the spores. Therefore, mycotoxin removal from the spore surface can occur without significant loss of polysaccharide. We also showed that toxic substances may be removed from the spore surface with an aqueous solution. These results suggest that satratoxins are soluble in aqueous solutions without being bound to water-soluble moieties, such as the carbohydrate slime matrix.

  14. Understanding the mathematics and science achievement and growth trajectories of high ability high school students using hierarchical linear modeling

    NASA Astrophysics Data System (ADS)

    Belen-Ferrer, Bellasanta

    2009-12-01

    This study used longitudinal data and individual, family, and academic-related matriculation variables to examine trends in initial status and growth trajectories in overall academics, mathematics, and science achievement among 224 high ability high school Asian students. Results indicate that females have an advantage in both initial status and growth rates in overall academics and science. None of the family variables entered in the models were found to be significantly related to overall academics grade point average. All available matriculation variables entered into the models explained less than or at most about half the variance in initial achievement status and growth rate in overall academics and science but not in mathematics. These results strongly imply that other factors, notably family and school and/or classroom-related variables, not measured by the ones used in the models could explain the expected variance in initial status and growth rate of the students especially in Mathematics.

  15. The Homeobox BcHOX8 Gene in Botrytis Cinerea Regulates Vegetative Growth and Morphology

    PubMed Central

    Antal, Zsuzsanna; Rascle, Christine; Cimerman, Agnès; Viaud, Muriel; Billon-Grand, Geneviève; Choquer, Mathias; Bruel, Christophe

    2012-01-01

    Filamentous growth and the capacity at producing conidia are two critical aspects of most fungal life cycles, including that of many plant or animal pathogens. Here, we report on the identification of a homeobox transcription factor encoding gene that plays a role in these two particular aspects of the development of the phytopathogenic fungus Botrytis cinerea. Deletion of the BcHOX8 gene in both the B. cinerea B05-10 and T4 strains causes similar phenotypes, among which a curved, arabesque-like, hyphal growth on hydrophobic surfaces; the mutants were hence named Arabesque. Expression of the BcHOX8 gene is higher in conidia and infection cushions than in developing appressorium or mycelium. In the Arabesque mutants, colony growth rate is reduced and abnormal infection cushions are produced. Asexual reproduction is also affected with abnormal conidiophore being formed, strongly reduced conidia production and dramatic changes in conidial morphology. Finally, the mutation affects the fungus ability to efficiently colonize different host plants. Analysis of the B. cinerea genome shows that BcHOX8 is one member of a nine putative homeobox genes family. Available gene expression data suggest that these genes are functional and sequence comparisons indicate that two of them would be specific to B. cinerea and its close relative Sclerotinia sclerotiorum. PMID:23133556

  16. Effect of Commercial Cyanobacteria Products on the Growth and Antagonistic Ability of Some Bioagents under Laboratory Conditions

    PubMed Central

    El-Mougy, Nehal S.; Abdel-Kader, Mokhtar M.

    2013-01-01

    Evaluation of the efficacy of blue-green algal compounds against the growth of either pathogenic or antagonistic microorganisms as well as their effect on the antagonistic ability of bioagents was studied under in vitro conditions. The present study was undertaken to explore the inhibitory effect of commercial algal compounds, Weed-Max and Oligo-Mix, against some soil-borne pathogens. In growth medium supplemented with these algal compounds, the linear growth of pathogenic fungi decreased by increasing tested concentrations of the two algal compounds. Complete reduction in pathogenic fungal growth was observed at 2% of both Weed-Max and Oligo-Mix. Gradual significant reduction in the pathogenic fungal growth was caused by the two bioagents and by increasing the concentrations of algal compounds Weed-Max and Oligo-Mix. The present work showed that commercial algal compounds, Weed-Max and Oligo-Mix, have potential for the suppression of soil-borne fungi and enhance the antagonistic ability of fungal, bacterial, and yeast bio-agents. PMID:24307948

  17. Production of conidia by entomopathogenic fungi: from inoculants to final quality tests.

    PubMed

    Muñiz-Paredes, Facundo; Miranda-Hernández, Francisco; Loera, Octavio

    2017-03-01

    Demand for biopesticides is growing due to the increase of areas under integrated pest management worldwide. Conidia from entomopathogenic fungi play a major role as infective units in the current market of biopesticides. Success in a massive production of fungal conidia include the use of proper long-term conservation microbial methods, aimed at preserving the phenotypic traits of the strains. The development of suitable inoculants should also be considered since that favours a rapid germination and invasiveness of the substrate in solid state cultures (SSC). After the selection of a suitable fungal strain, proven optimization approaches for SSC mainly include the combination of substrates, moisture, texturizers, aeration and moderate stress to induce conidiation. Nonetheless, during storage and upon application in open fields, conidia either as free propagules or imbibed in formulations are subjected to stress due to abiotic factors, then quality should be preserved to resist such harsh conditions. All of these topics are analysed in this report.

  18. Copulation Activity, Sperm Production and Conidia Transfer in Aedes aegypti Males Contaminated by Metarhizium anisopliae: A Biological Control Prospect.

    PubMed

    Garza-Hernández, Javier A; Reyes-Villanueva, Filiberto; Russell, Tanya L; Braks, Marieta A H; Garcia-Munguia, Alberto M; Rodríguez-Pérez, Mario A

    2015-01-01

    Dengue is the most prevalent arboviral disease transmitted by Aedes aegypti worldwide, whose chemical control is difficult, expensive, and of inconsistent efficacy. Releases of Metarhizium anisopliae--exposed Ae. aegypti males to disseminate conidia among female mosquitoes by mating represents a promising biological control approach against this important vector. A better understanding of fungus virulence and impact on reproductive parameters of Ae. aegypti, is need before testing auto-dissemination strategies. Mortality, mating competitiveness, sperm production, and the capacity to auto-disseminate the fungus to females up to the 5 th copulation, were compared between Aedes aegypti males exposed to 5.96 x 10(7) conidia per cm2 of M. anisopliae and uninfected males. Half (50%) of fungus-exposed males (FEMs) died within the first 4 days post-exposure (PE). FEMs required 34% more time to successively copulate with 5 females (165 ± 3 minutes) than uninfected males (109 ± 3 minutes). Additionally, fungus infection reduced the sperm production by 87% at 5 days PE. Some beneficial impacts were observed, FEMs were able to successfully compete with uninfected males in cages, inseminating an equivalent number of females (about 25%). Under semi-field conditions, the ability of FEMs to search for and inseminate females was also equivalent to uninfected males (both inseminating about 40% females); but for the remaining females that were not inseminated, evidence of tarsal contact (transfer of fluorescent dust) was significantly greater in FEMs compared to controls. The estimated conidia load of a female exposed on the 5th copulation was 5,200 mL(-1) which was sufficient to cause mortality. Our study is the first to demonstrate auto-dissemination of M. anisopliae through transfer of fungus from males to female Ae. aegypti during mating under semi-field conditions. Our results suggest that auto-dissemination studies using releases of FEMs inside households could successfully

  19. Copulation Activity, Sperm Production and Conidia Transfer in Aedes aegypti Males Contaminated by Metarhizium anisopliae: A Biological Control Prospect

    PubMed Central

    Russell, Tanya L.; Braks, Marieta A. H.

    2015-01-01

    Background Dengue is the most prevalent arboviral disease transmitted by Aedes aegypti worldwide, whose chemical control is difficult, expensive, and of inconsistent efficacy. Releases of Metarhizium anisopliae—exposed Ae. aegypti males to disseminate conidia among female mosquitoes by mating represents a promising biological control approach against this important vector. A better understanding of fungus virulence and impact on reproductive parameters of Ae. aegypti, is need before testing auto-dissemination strategies. Methodology/Principal Findings Mortality, mating competitiveness, sperm production, and the capacity to auto-disseminate the fungus to females up to the 5thcopulation, were compared between Aedes aegypti males exposed to 5.96 x 107 conidia per cm2 of M. anisopliae and uninfected males. Half (50%) of fungus-exposed males (FEMs) died within the first 4 days post-exposure (PE). FEMs required 34% more time to successively copulate with 5 females (165 ± 3 minutes) than uninfected males (109 ± 3 minutes). Additionally, fungus infection reduced the sperm production by 87% at 5 days PE. Some beneficial impacts were observed, FEMs were able to successfully compete with uninfected males in cages, inseminating an equivalent number of females (about 25%). Under semi-field conditions, the ability of FEMs to search for and inseminate females was also equivalent to uninfected males (both inseminating about 40% females); but for the remaining females that were not inseminated, evidence of tarsal contact (transfer of fluorescent dust) was significantly greater in FEMs compared to controls. The estimated conidia load of a female exposed on the 5th copulation was 5,200 mL-1 which was sufficient to cause mortality. Conclusion/Significance Our study is the first to demonstrate auto-dissemination of M. anisopliae through transfer of fungus from males to female Ae. aegypti during mating under semi-field conditions. Our results suggest that auto-dissemination studies

  20. Influence of antibiotics on growth dynamics and movement ability of Salmonella rods.

    PubMed

    Rzedzicki, J; Boś, M; Kolasa, A

    2004-01-01

    Variety of traits important in diagnostics and epidemiology of pathogenic microorganisms may change due to antibiotics. Movement ability, that is characteristic for every serovar except from Salmonella Gallinarum-Pullorum, is important to salmonellas. In own experiments using semi-fluid MSRV medium, it was found that a decrease in salmonella sensibility to selected antibiotics and chemiotherapeutics due to passage might lead to weakening of its movement ability. Movement ability of all strains (S. Enteritidis, S. Dublin, S. Typhimurium) after passage with amoxycillin, neomycin, colistin and enrofloxacin became weakened as compared to results achieved before passage. The strongest inhibition of movement ability was most often observed in strains after passage on medium with colistin. It seems to be associated with the action mechanism of the antibiotic. Colistin injuries cellular membranes, where flagella (active motoric organ of Salmonella) are anchored. Appearance of drug-resistance as a result of passage at the presence of antibiotics may cause variability of biochemical properties of Salmonella rods and leads to weakening of movement ability of ciliated Salmonella.

  1. Ability of Cecal Cultures to Inhibit Growth of Salmonella Typhimurium during Aerobic Incubation

    USDA-ARS?s Scientific Manuscript database

    Introduction: Poultry can serve as reservoirs for Salmonella; however, chicks provided cultures of cecal bacteria develop resistance to colonization by Salmonella. Research has indicated that cecal bacteria metabolize organic acids to produce substances that inhibit Salmonella growth. Purpose: The...

  2. Early neutrophil recruitment and aggregation in the murine lung inhibit germination of Aspergillus fumigatus Conidia.

    PubMed

    Bonnett, Colin R; Cornish, E Jean; Harmsen, Allen G; Burritt, James B

    2006-12-01

    Several types of polymorphonuclear neutrophil (PMN) deficiency are a predisposing condition for fatal Aspergillus fumigatus infection. In order to study the defensive role of PMNs in the lungs, with particular reference to PMN recruitment and antimicrobial oxidant activity, responses to pulmonary instillation of A. fumigatus conidia were examined. Responses in BALB/c and C57BL/6 mice were compared with those in CXCR2(-/-) and gp91(phox-/-) mice, which are known to have delayed recruitment of PMN to the lungs in response to inflammatory stimuli and inactive NADPH oxidase, respectively. In BALB/c mice, PMNs were recruited to the lungs and formed oxidase-active aggregates with conidia, which inhibited germination. In C57BL/6, gp91(phox-/-), and CXCR2(-/-) mice, PMN recruitment was slower and there was increased germination compared to that in BALB/c mice at 6 and 12 h. In gp91(phox-/-) mice, germination was extensive in PMN aggregates but negligible in alveolar macrophages (AM). Lung sections taken at 6 and 48 h from BALB/c mice showed PMN accumulation at peribronchiolar sites but no germinating conidia. Those from C57BL/6 and CXCR2(-/-) mice showed germinating conidia at 6 h but not at 48 h and few inflammatory cells. In contrast, those from gp91(phox-/-) mice showed germination at 6 h with more-extensive hyphal proliferation and tissue invasion at 48 h. These results indicate that when the lungs are exposed to large numbers of conidia, in addition to the phagocytic activity of AM, early PMN recruitment and formation of oxidative-active aggregates are essential in preventing germination of A. fumigatus conidia.

  3. A Murine Inhalation Model to Characterize Pulmonary Exposure to Dry Aspergillus fumigatus Conidia

    PubMed Central

    Buskirk, Amanda D.; Green, Brett J.; Lemons, Angela R.; Nayak, Ajay P.; Goldsmith, W. Travis; Kashon, Michael L.; Anderson, Stacey E.; Hettick, Justin M.; Templeton, Steven P.; Germolec, Dori R.; Beezhold, Donald H.

    2014-01-01

    Most murine models of fungal exposure are based on the delivery of uncharacterized extracts or liquid conidia suspensions using aspiration or intranasal approaches. Studies that model exposure to dry fungal aerosols using whole body inhalation have only recently been described. In this study, we aimed to characterize pulmonary immune responses following repeated inhalation of conidia utilizing an acoustical generator to deliver dry fungal aerosols to mice housed in a nose only exposure chamber. Immunocompetent female BALB/cJ mice were exposed to conidia derived from Aspergillus fumigatus wild-type (WT) or a melanin-deficient (Δalb1) strain. Conidia were aerosolized and delivered to mice at an estimated deposition dose of 1×105 twice a week for 4 weeks (8 total). Histopathological and immunological endpoints were assessed 4, 24, 48, and 72 hours after the final exposure. Histopathological analysis showed that conidia derived from both strains induced lung inflammation, especially at 24 and 48 hour time points. Immunological endpoints evaluated in bronchoalveolar lavage fluid (BALF) and the mediastinal lymph nodes showed that exposure to WT conidia led to elevated numbers of macrophages, granulocytes, and lymphocytes. Importantly, CD8+ IL17+ (Tc17) cells were significantly higher in BALF and positively correlated with germination of A. fumigatus WT spores. Germination was associated with specific IgG to intracellular proteins while Δalb1 spores elicited antibodies to cell wall hydrophobin. These data suggest that inhalation exposures may provide a more representative analysis of immune responses following exposures to environmentally and occupationally prevalent fungal contaminants. PMID:25340353

  4. Morphological Transition of Paracoccidioides brasiliensis Conidia to Yeast Cells: In Vivo Inhibition in Females

    PubMed Central

    Aristizabal, Beatriz H.; Clemons, Karl V.; Stevens, David A.; Restrepo, Angela

    1998-01-01

    Clinical paracoccidioidomycosis is 13 times more common in men than in women. Estrogen inhibits the transition of mycelia or conidia (the saprophytic form of Paracoccidoides brasiliensis) to yeasts (the parasitic form) in vitro. Here, we show that, in male mice that were infected intranasally (mimicking natural infection) the transition of conidia in bronchoalveolar lavage fluids to intermediate forms and yeasts occurred over 24 to 96 h; CFU and yeasts (shown by histopathology) increased subsequently. In females, transition did not occur and infection cleared. These events in vivo are consistent with epidemiological and in vitro observations, suggesting that female hormones block transition and are responsible for resistance. PMID:9784579

  5. Ability-Growth Interactions in the Acquisition of a Complex Skill: A Spline-Modeling Approach

    ERIC Educational Resources Information Center

    Schuelke, Matthew J.

    2010-01-01

    While investigating how the relationship of abilities and skill acquisition changes over the course of training, researchers have unknowingly obscured the very relationship they sought to examine by relying on analyses that focused on attainment and did not model acquisition. Although more recent approaches have modeled acquisition independently…

  6. Comparison of two growth charts in Lesotho: health workers' ability to understand and use them for action.

    PubMed Central

    Ruel, M T; Pelletier, D L; Habicht, J P; Mason, J B; Chobokoane, C S; Maruping, A P

    1991-01-01

    BACKGROUND: Two growth monitoring charts widely used for growth monitoring in Africa (the Road-to-Health (RTH) and the Growth Surveillance (GS] were compared in order to assist the Government of Lesotho to decide on an appropriate national growth chart. METHODS: Thirty-four health workers were taught and tested on the RTH during a first week of training and on the GS during a second week (the RTH-GS group), while the order was reversed for another 25 trainees (the GS-RTH group). The health workers were trained and tested on their ability not only to use and interpret the two charts, but also to make the right decisions about specific actions to be taken when growth faltering occurs. RESULTS: There was no difference between scores to the RTH and GS charts after one week of training. After the second week of training, the scores to the RTH chart improved and became better than those to the GS chart. The scores to the GS test did not increase with previous knowledge of the RTH chart. CONCLUSIONS: For this reason and others discussed in the paper, the RTH chart was recommended for nationwide use in Lesotho. The adoption of this recommendation was facilitated by the close involvement in this research of public and private agencies responsible for growth monitoring in Lesotho. Images FIGURE 2B PMID:2014861

  7. Recognition of laminin by Paracoccidioides brasiliensis conidia: a possible mechanism of adherence to human type II alveolar cells.

    PubMed

    Caro, Erika; Gonzalez, Angel; Muñoz, César; Urán, Marta E; Restrepo, Angela; John Hamilton, Andrew; Elena Cano, Luz

    2008-12-01

    This study addresses the recognition of laminin by Paracoccidioides brasiliensis conidia, as well as its possible role in the adherence of conidia to A549 cells. Adherence of conidia to immobilized laminin was shown to be specific, as anti-laminin antibodies, soluble laminin or the laminin-derived peptides IKVAV and CDPGYIGSR inhibited this interaction. RGD containing peptides and various monosaccharides had no effect on adherence, with the exception of N-acetylneuraminic acid. Pre-treatment of conidia with fibrinogen and fibronectin, but not with BSA, also resulted in significant inhibition, suggesting that P. brasiliensis conidia might cross-recognize host proteins involved in colonization. In assays using transmission electron microscopy, we observed internalization of conidia 30 min after exposition to A549 cells. Laminin present on the surface of A549 cells shown to serve as mediator of this interaction, with a significant decrease in fungal adherence when the epithelial cells were pre-treated with anti-laminin antibodies or when conidia were pre-incubated with either soluble laminin or the laminin-specific peptides. Together these results suggest that the recognition of laminin by P. brasiliensis conidia is a key process in the interaction with pulmonary epithelial cells, where this extracellular matrix protein acts as bridging molecule.

  8. Influence of Infection Court, Host Vigor, and Culture Filtrates on Canker Production by Botryodiplodia Theobromae Conidia in Sycamore

    Treesearch

    R. Lewis

    1978-01-01

    Some of the factors that influence canker development in American sycamores inoculated with Botryodiplodia theobromae conidia were determined. A combination of B. theobromae culture filtrates and conidia resulted in 100% canker production when introduced into stem wounds; however, a combination of Cephalosporium diospyri...

  9. Influence of serotype on the growth kinetics and the ability to form biofilms of Salmonella isolates from poultry.

    PubMed

    Díez-García, Miryam; Capita, Rosa; Alonso-Calleja, Carlos

    2012-09-01

    The influence of the serotype on the growth behaviour and the ability to form biofilms of Salmonella enterica strains was investigated. The relationships between biofilm formation and growth kinetic parameters were also determined. A total of 69 strains (61 isolates from poultry and 8 reference strains from culture collections) belonging to 10 serotypes (S. enterica serotype Typhimurium, S. Newport, S. Paratyphi B, S. Poona, S. Derby, S. Infantis, S. Enteritidis, S. Virchow, S. Agona and S. Typhi) were tested. All Salmonella strains produced biofilms on polystyrene micro-well plates (crystal violet assay). Isolates were classified as weak (35 strains), moderate (22), or strong (12) biofilm producers. S. Agona and S. Typhi produced the most substantial (P < 0.001) biofilms. Growth curves were performed at 37 °C in tryptone soy broth by means of optical density (OD(420-580)) measurements from 0 to 48 h. Growth kinetic parameters (Gompertz model) varied between serotypes. The maximum growth rate (ΔOD(420-580)/h) ranged from 0.030 ± 0.002 (S. Typhi) to 0.114 ± 0.011 (S. Agona). The ability of Salmonella strains to form biofilms was not related to their growth kinetic parameters. The formation of biofilms by Salmonella on polystyrene constitutes an issue of concern because plastic materials are frequently used in food facilities. The findings suggest that special efforts must be made for the effective control of Salmonella in food-processing environments when S. Agona or S. Typhi strains are present. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Patterns of Growth in Adaptive Social Abilities among Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Anderson, Deborah K.; Oti, Rosalind S.; Lord, Catherine; Welch, Kathleen

    2009-01-01

    Adaptive social skills were assessed longitudinally at approximately ages 2, 3, 5, 9, and 13 years in a sample of 192 children with a clinical diagnosis of autism (n = 93), PDD-NOS (n = 51), or nonspectrum developmental disabilities (n = 46) at age 2. Growth curve analyses with SAS proc mixed were used to analyze social trajectories over time.…

  11. Patterns of Growth in Verbal Abilities among Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Anderson, Deborah K.; Lord, Catherine; Risi, Susan; DiLavore, Pamela S.; Shulman, Cory; Thurm, Audrey; Welch, Kathleen; Pickles, Andrew

    2007-01-01

    Verbal skills were assessed at approximately ages 2, 3, 5, and 9 years for 206 children with a clinical diagnosis of autism (n = 98), pervasive developmental disorders-not otherwise specified (PDD-NOS; n = 58), or nonspectrum developmental disabilities (n = 50). Growth curve analyses were used to analyze verbal skills trajectories over time.…

  12. Patterns of Growth in Adaptive Social Abilities among Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Anderson, Deborah K.; Oti, Rosalind S.; Lord, Catherine; Welch, Kathleen

    2009-01-01

    Adaptive social skills were assessed longitudinally at approximately ages 2, 3, 5, 9, and 13 years in a sample of 192 children with a clinical diagnosis of autism (n = 93), PDD-NOS (n = 51), or nonspectrum developmental disabilities (n = 46) at age 2. Growth curve analyses with SAS proc mixed were used to analyze social trajectories over time.…

  13. Optimization of compatible non-ionic surfactant for formulation development of hydrophobic conidia of entomopathogenic fungi, Beauveria bassiana (Hypocreales:Cordycipitaceae) and Metarhizium anisopliae Hypocreales:Clavicipita

    USDA-ARS?s Scientific Manuscript database

    Aerial conidia, especially dried conidia of entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae are hydrophobic, and therefore surfactants are needed for developing water-based formulations in laboratory studies, greenhouse bioassays, and field trials as well as commercial product ...

  14. Temperature during conidiation affects stress tolerance, pigmentation, and trypacidin accumulation in the conidia of the airborne pathogen Aspergillus fumigatus.

    PubMed

    Hagiwara, Daisuke; Sakai, Kanae; Suzuki, Satoshi; Umemura, Myco; Nogawa, Toshihiko; Kato, Naoki; Osada, Hiroyuki; Watanabe, Akira; Kawamoto, Susumu; Gonoi, Tohru; Kamei, Katsuhiko

    2017-01-01

    Asexual spores (conidia) are reproductive structures that play a crucial role in fungal distribution and survival. As fungal conidia are, in most cases, etiological agents of plant diseases and fungal lung disease, their stress resistance and interaction with their hosts have drawn increasing attention. In the present study, we investigated whether environmental temperature during conidiation affects the stress tolerance of the conidia of the human pathogenic fungus Aspergillus fumigatus. Conidia from a 25°C culture showed a lower tolerance to heat (60°C) and oxidative (H2O2) stresses and a marked resistance to ultraviolet radiation exposure, compared with those produced at 37 and 45°C. The accumulation of trehalose was lower in the conidia from the 25°C culture. Furthermore, the conidia from the 25°C culture showed darker pigmentation and increased transcripts of dihydroxynaphthalene (DHN)-melanin biosynthesis-related genes (i.e., pksP, arp1, and arp2). An RNA-sequencing analysis revealed that the transcription level of the trypacidin (tpc) gene cluster, which contains 13 genes, was sharply and coordinately activated in the conidia from the 25°C culture. Accordingly, trypacidin was abundant in the conidia from the 25°C culture, whereas there was little trypacidin in the conidia from the 37°C culture. Taken together, these data show that the environmental temperature during conidiation affects conidial properties such as stress tolerance, pigmentation, and mycotoxin accumulation. To enhance our knowledge, we further explored the temperature-dependent production of DHN-melanin and trypacidin in clinical A. fumigatus isolates. Some of the isolates showed temperature-independent production of DHN-melanin and/or trypacidin, indicating that the conidia-associated secondary metabolisms differed among the isolates.

  15. Temperature during conidiation affects stress tolerance, pigmentation, and trypacidin accumulation in the conidia of the airborne pathogen Aspergillus fumigatus

    PubMed Central

    Sakai, Kanae; Suzuki, Satoshi; Umemura, Myco; Nogawa, Toshihiko; Kato, Naoki; Osada, Hiroyuki; Watanabe, Akira; Kawamoto, Susumu; Gonoi, Tohru; Kamei, Katsuhiko

    2017-01-01

    Asexual spores (conidia) are reproductive structures that play a crucial role in fungal distribution and survival. As fungal conidia are, in most cases, etiological agents of plant diseases and fungal lung disease, their stress resistance and interaction with their hosts have drawn increasing attention. In the present study, we investigated whether environmental temperature during conidiation affects the stress tolerance of the conidia of the human pathogenic fungus Aspergillus fumigatus. Conidia from a 25°C culture showed a lower tolerance to heat (60°C) and oxidative (H2O2) stresses and a marked resistance to ultraviolet radiation exposure, compared with those produced at 37 and 45°C. The accumulation of trehalose was lower in the conidia from the 25°C culture. Furthermore, the conidia from the 25°C culture showed darker pigmentation and increased transcripts of dihydroxynaphthalene (DHN)-melanin biosynthesis-related genes (i.e., pksP, arp1, and arp2). An RNA-sequencing analysis revealed that the transcription level of the trypacidin (tpc) gene cluster, which contains 13 genes, was sharply and coordinately activated in the conidia from the 25°C culture. Accordingly, trypacidin was abundant in the conidia from the 25°C culture, whereas there was little trypacidin in the conidia from the 37°C culture. Taken together, these data show that the environmental temperature during conidiation affects conidial properties such as stress tolerance, pigmentation, and mycotoxin accumulation. To enhance our knowledge, we further explored the temperature-dependent production of DHN-melanin and trypacidin in clinical A. fumigatus isolates. Some of the isolates showed temperature-independent production of DHN-melanin and/or trypacidin, indicating that the conidia-associated secondary metabolisms differed among the isolates. PMID:28486558

  16. Physical growth and cognitive abilities in concordant versus discordant birth weight twins at three years old.

    PubMed

    Ross, Gail S; Krauss, Alfred N; Perlman, Jeffrey M

    2012-09-01

    Discordant birth weight twins have been shown to have high rates of adverse perinatal outcomes, but little is known about their growth and development. To determine whether smaller and larger birth weight premature twins in concordant and discordant birth weight groups differ on measures of physical growth and intelligence at 3 years. Prospective cohort study. Eight-four children, 52 concordant and 32 discordant birth weight twin pairs, were measured for height, weight, and head circumference and on intelligence at 3 years. Perinatal and demographic variables, including birth weight, head circumference, small for gestational age, zygosity, in vitro fertilization, gender and social class were recorded. Smaller and larger birth weight twins did not differ significantly from each other on any growth parameters in either concordant or discordant birth weight groups at 3 years of age. Smaller birth weight twins in the discordant birth weight group performed significantly less well on Verbal, Performance, and Full Scale IQ scores (Verbal IQ for smaller twins was 8.6 points lower, p<0.005; Performance IQ, 11.9 points lower, p<0.03; Full Scale IQ, 12.4 points lower, p<0.004), but there were no significant intra-twin differences between larger and smaller birth weight concordant twins. Smaller discordant birth weight twins performed significantly less well on intelligence, although they did not differ significantly from their larger twins on growth parameters at 3 years old. We conclude that smaller discordant birth weight twins had less optimal intra-uterine environments than their larger birth weight twin, which affected both their birth weights and brain development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Density, Viability Conidia And Symptoms of Metarhizium anisopliae infection on Oryctes rhinoceros larvae

    NASA Astrophysics Data System (ADS)

    Indriyanti, D. R.; Putri, R. I. P.; Widiyaningrum, P.; Herlina, L.

    2017-04-01

    M. anisopliae is parasitic fungus on insect pests; it is used as a biocontrol agent. M. anisopliae can be propagated on maize or rice substrate. M. anisopliae is currently sold in the form of kaolin powder formulations. Before it is used to check the density, viability and pathogenicity of M. anisopliae. However the problem is the kaolin powder very soft, so it difficult to distinguish between kaolin and conidia. This article gives information on how to calculate conidia density, viability and symptoms of M. anisopliae infection on Oryctes rhinoceros larvae. The study was conducted in the laboratory to determine the density and viability. The pathogenicity testing was done using pots. The Pot is containing soil substrate mixed with M. Anispoliae and ten tails O. Rhinoceros larvae per pot. The results showed that the density of M. anisopliae conidia was 1.81 x 108 conidia mL-1 and the viability was 94% within 24 hours. The larval mortality began to emerge in the 1st week, and all larvae died at the sixth week. The symptom of M. anisopliae infection on Oryctes rhinoceros larvae, there was a black spot on the larval integument. The larvae movements become slow and poor appetite; it will die within 3-7 days. The larvae die hard, and the white hyphae grow on the body surface that turns green.

  18. Interactions of Aspergillus fumigatus Conidia with Airway Epithelial Cells: A Critical Review

    PubMed Central

    Croft, Carys A.; Culibrk, Luka; Moore, Margo M.; Tebbutt, Scott J.

    2016-01-01

    Aspergillus fumigatus is an environmental filamentous fungus that also acts as an opportunistic pathogen able to cause a variety of symptoms, from an allergic response to a life-threatening disseminated fungal infection. The infectious agents are inhaled conidia whose first point of contact is most likely to be an airway epithelial cell (AEC). The interaction between epithelial cells and conidia is multifaceted and complex, and has implications for later steps in pathogenesis. Increasing evidence has demonstrated a key role for the airway epithelium in the response to respiratory pathogens, particularly at early stages of infection; therefore, elucidating the early stages of interaction of conidia with AECs is essential to understand the establishment of infection in cohorts of at-risk patients. Here, we present a comprehensive review of the early interactions between A. fumigatus and AECs, including bronchial and alveolar epithelial cells. We describe mechanisms of adhesion, internalization of conidia by AECs, the immune response of AECs, as well as the role of fungal virulence factors, and patterns of fungal gene expression characteristic of early infection. A clear understanding of the mechanisms involved in the early establishment of infection by A. fumigatus could point to novel targets for therapy and prophylaxis. PMID:27092126

  19. Absorbing film assisted laser induced forward transfer of fungi (Trichoderma conidia)

    NASA Astrophysics Data System (ADS)

    Hopp, B.; Smausz, T.; Antal, Zs.; Kresz, N.; Bor, Zs.; Chrisey, D.

    2004-09-01

    We present an investigation on absorbing film assisted laser induced forward transfer (AFA-LIFT) of fungus (Trichoderma) conidia. A KrF excimer laser beam [λ =248nm,FWHM=30ns (FWHM, full width at half maximum)] was directed through a quartz plate and focused onto its silver coated surface where conidia of the Trichoderma strain were uniformly spread. The laser fluence was varied in the range of 0-2600mJ/cm2 and each laser pulse transferred a pixel of target material. The average irradiated area was 8×10-2mm2. After the transfer procedure, the yeast extract medium covered glass slide and the transferred conidia patterns were incubated for 20 h and then observed using an optical microscope. The transferred conidia pixels were germinated and the areas of the culture medium surfaces covered by the pixels were evaluated as a function of laser fluence. As the laser fluence was increased from 0 to 355mJ/cm2 the transferred and germinated pixel area increased from 0 to 0.25mm2. Further increase in fluence resulted in a drastic decrease down to an approximately constant value of 0.06mm2. The yield of successful transfer by AFA-LIFT and germination was as much as 75% at 355mJ/cm2. The results prove that AFA-LIFT can successfully be applied for the controlled transfer of biological objects.

  20. Evaluation of Soyscreen in an Oil-based Formulation for UV Protection of Beauveria bassiana Conidia

    USDA-ARS?s Scientific Manuscript database

    SoyScreen oil was studied as a formulation ingredient to protect Beauveria bassiana (Balsamo) Vuillemin conidia from UV degradation. Feruloylated soy glycerides, referred to as SoyScreen oil, are biobased ultraviolet-absorbing molecules made by combining molecules of soybean oil with ferulic acid. ...

  1. Metacridamides A and B, bioactive macrocycles from conidia of the entomopathogenic fungus Metarhizium acridum

    USDA-ARS?s Scientific Manuscript database

    Metarhizium acridum, an entomopathogenic fungus, has been commercialized and used successfully for biocontrol of grasshopper pests in Africa and Australia. Its conidia produce two novel 17-membered macrocycles, metacridamides A (1) and B (2), which consist of a Phe unit condensed with a nonaketide....

  2. Diversity, Biocontrol, and Plant Growth Promoting Abilities of Xylem Residing Bacteria from Solanaceous Crops

    PubMed Central

    Achari, Gauri A.

    2014-01-01

    Eggplant (Solanum melongena L.) is one of the solanaceous crops of economic and cultural importance and is widely cultivated in the state of Goa, India. Eggplant cultivation is severely affected by bacterial wilt caused by Ralstonia solanacearum that colonizes the xylem tissue. In this study, 167 bacteria were isolated from the xylem of healthy eggplant, chilli, and Solanum torvum Sw. by vacuum infiltration and maceration. Amplified rDNA restriction analysis (ARDRA) grouped these xylem residing bacteria (XRB) into 38 haplotypes. Twenty-eight strains inhibited growth of R. solanacearum and produced volatile and diffusible antagonistic compounds and plant growth promoting substances in vitro. Antagonistic strains XB86, XB169, XB177, and XB200 recorded a biocontrol efficacy greater than 85% against BW and exhibited 12%–22 % increase in shoot length in eggplant in the greenhouse screening. 16S rRNA based identification revealed the presence of 23 different bacterial genera. XRB with high biocontrol and plant growth promoting activities were identified as strains of Staphylococcus sp., Bacillus sp., Streptomyces sp., Enterobacter sp., and Agrobacterium sp. This study is the first report on identity of bacteria from the xylem of solanaceous crops having traits useful in cultivation of eggplant. PMID:24963298

  3. Pantoea alhagi, a novel endophytic bacterium with ability to improve growth and drought tolerance in wheat

    PubMed Central

    Chen, Chaoqiong; Xin, Kaiyun; Liu, Hao; Cheng, Juanli; Shen, Xihui; Wang, Yao; Zhang, Lei

    2017-01-01

    A novel strain LTYR-11ZT that exhibited multiple plant growth promoting (PGP) traits was isolated from the surface-sterilized leaves of Alhagi sparsifolia Shap. (Leguminosae), which reprsents one of the top drought tolerant plants in north-west China. Phylogenetic analysis of 16S rRNA gene sequences and multilocus sequence analysis based on partial sequences of atpD, gyrB, infB and rpoB genes revealed that strain LTYR-11ZT was a member of the genus Pantoea, with Pantoea theicola NBRC 110557T and Pantoea intestinalis DSM 28113T as the closest phylogenetic relatives. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analysis confirmed that strain LTYR-11ZT represents a novel species of the genus Pantoea, for which we propose the name Pantoea alhagi sp. nov. Confocal microscopy observation revealed that strain LTYR-11ZT effectively colonizes the rhizoplane of both Arabidopsis and wheat. Strain LTYR-11ZT was able to promote the growth of wheat enhancing its resistance to drought stress. Strain LTYR-11ZT led to increased accumulation of soluble sugars, decreased accumulation of proline and malondialdehyde (MDA), and decreased degradation of chlorophyll in leaves of drought-stressed wheat. Our findings will contribute to the development of a novel biotechnological agent to improve the adaptation of crop plants to drought in arid ecosystems. PMID:28128318

  4. Patterns of growth in verbal abilities among children with autism spectrum disorder.

    PubMed

    Anderson, Deborah K; Lord, Catherine; Risi, Susan; DiLavore, Pamela S; Shulman, Cory; Thurm, Audrey; Welch, Kathleen; Pickles, Andrew

    2007-08-01

    Verbal skills were assessed at approximately ages 2, 3, 5, and 9 years for 206 children with a clinical diagnosis of autism (n = 98), pervasive developmental disorders-not otherwise specified (PDD-NOS; n = 58), or nonspectrum developmental disabilities (n = 50). Growth curve analyses were used to analyze verbal skills trajectories over time. Nonverbal IQ and joint attention emerged as strong positive predictors of verbal outcome. The gap between the autism and other 2 groups widened with time as the latter improved at a higher rate. However, there was considerable variability within diagnostic groups. Children with autism most at risk for more serious language impairments later in life can be identified with considerable accuracy at a very young age, while improvement can range from minimal to dramatic.

  5. Ability for anaerobic growth is not sufficient for development of the petite phenotype in Saccharomyces kluyveri.

    PubMed

    Møller, K; Olsson, L; Piskur, J

    2001-04-01

    Saccharomyces cerevisiae is a petite-phenotype-positive ("petite-positive") yeast, which can successfully grow in the absence of oxygen. On the other hand, Kluyveromyces lactis as well as many other yeasts are petite negative and cannot grow anaerobically. In this paper, we show that Saccharomyces kluyveri can grow under anaerobic conditions, but while it can generate respiration-deficient mutants, it cannot generate true petite mutants. From a phylogenetic point of view, S. kluyveri is apparently more closely related to S. cerevisiae than to K. lactis. These observations suggest that the progenitor of the modern Saccharomyces and Kluyveromyces yeasts, as well as other related genera, was a petite-negative and aerobic yeast. Upon separation of the K. lactis and S. kluyveri-S. cerevisiae lineages, the latter developed the ability to grow anaerobically. However, while the S. kluyveri lineage has remained petite negative, the lineage leading to the modern Saccharomyces sensu stricto and sensu lato yeasts has developed the petite-positive characteristic.

  6. Ability for Anaerobic Growth Is Not Sufficient for Development of the Petite Phenotype in Saccharomyces kluyveri

    PubMed Central

    Mo/ller, Kasper; Olsson, Lisbeth; Piškur, Jure

    2001-01-01

    Saccharomyces cerevisiae is a petite-phenotype-positive (“petite-positive”) yeast, which can successfully grow in the absence of oxygen. On the other hand, Kluyveromyces lactis as well as many other yeasts are petite negative and cannot grow anaerobically. In this paper, we show that Saccharomyces kluyveri can grow under anaerobic conditions, but while it can generate respiration-deficient mutants, it cannot generate true petite mutants. From a phylogenetic point of view, S. kluyveri is apparently more closely related to S. cerevisiae than to K. lactis. These observations suggest that the progenitor of the modern Saccharomyces and Kluyveromyces yeasts, as well as other related genera, was a petite-negative and aerobic yeast. Upon separation of the K. lactis and S. kluyveri-S. cerevisiae lineages, the latter developed the ability to grow anaerobically. However, while the S. kluyveri lineage has remained petite negative, the lineage leading to the modern Saccharomyces sensu stricto and sensu lato yeasts has developed the petite-positive characteristic. PMID:11274107

  7. An animal model for allergic penicilliosis induced by the intranasal instillation of viable Penicillium chrysogenum conidia

    PubMed Central

    Cooley, J; Wong, W; Jumper, C; Hutson, J; Williams, H; Schwab, C; Straus, D

    2000-01-01

    BACKGROUND—A study was undertaken to determine the consequences of long term intranasal instillation of Penicillium chrysogenum propagules in a mouse model.
METHODS—C57 Black/6 mice were inoculated intranasally each week for six weeks with 104 viable and non-viable P chrysogenum conidia. Cytokine levels and cellular responses in these animals were then measured.
RESULTS—Compared with controls, mice inoculated intranasally each week for six weeks with 104P chrysogenum conidia (average viability 25%) produced significantly more total serum IgE (mean difference 1823.11, lower and upper 95% confidence intervals (CI) 539.09 to 3107.13), peripheral eosinophils (mean difference 5.11, 95% CI 2.24 to 7.99), and airway eosinophilia (rank difference 11.33, 95% CI 9.0 to 20.0). With the exception of airway neutrophilia (mean difference 20.89, 95% CI 3.72 to 38.06), mice inoculated intranasally with 104 non-viable conidia did not show significant changes in total serum IgE, peripheral or airway eosinophils. However, when compared with controls, this group (104 non-viable) had a significant increase in total serum IgG2a (mean difference 1990.56, 95% CI 790.48 to 3190.63) and bronchoalveolar lavage (BAL) fluid levels of interferon (IFN)-γ (mean difference 274.72, 95% CI 245.26 to 304.19). In addition, lung lavages from mice inoculated intranasally with 104 viable P chrysogenum conidia had significantly increased levels of interleukin (IL)-4 (mean difference 285.28, 95% CI 108.73 to 461.82) and IL-5 (mean difference 16.61, 95% CI 11.23 to 21.99). The IgG2a/IgE ratio and the IFN-γ/IL-4 ratio was lower in the group of mice inoculated intranasally with 104 viable conidia than in the 104 non-viable conidia group and the controls. When proteins were extracted from P chrysogenum conidia, attached to microtitre plates and incubated with serum from the 104 viable group, significant increases in conidia-specific IgE and IgG1 were observed compared with controls, while serum

  8. Chimeras of p14ARF and p16: Functional Hybrids with the Ability to Arrest Growth

    PubMed Central

    Williams, Richard T.; Barnhill, Lisa M.; Kuo, Huan-Hsien; Lin, Wen-Der; Batova, Ayse; Yu, Alice L.; Diccianni, Mitchell B.

    2014-01-01

    The INK4A locus codes for two independent tumor suppressors, p14ARF and p16/CDKN2A, and is frequently mutated in many cancers. Here we report a novel deletion/substitution from CC to T in the shared exon 2 of p14ARF/p16 in a melanoma cell line. This mutation aligns the reading frames of p14ARF and p16 mid-transcript, producing one protein which is half p14ARF and half p16, chimera ARF (chARF), and another which is half p16 and half non-p14ARF/non-p16 amino acids, p16-Alternate Carboxyl Terminal (p16-ACT). In an effort to understand the cellular impact of this novel mutation and others like it, we expressed the two protein products in a tumor cell line and analyzed common p14ARF and p16 pathways, including the p53/p21 and CDK4/cyclin D1 pathways, as well as the influence of the two proteins on growth and the cell cycle. We report that chARF mimicked wild-type p14ARF by inducing the p53/p21 pathway, inhibiting cell growth through G2/M arrest and maintaining a certain percentage of cells in G1 during nocodazole-induced G2 arrest. chARF also demonstrated p16 activity by binding CDK4. However, rather than preventing cyclin D1 from binding CDK4, chARF stabilized this interaction through p21 which bound CDK4. p16-ACT had no p16-related function as it was unable to inhibit cyclin D1/CDK4 complex formation and was unable to arrest the cell cycle, though it did inhibit colony formation. We conclude that these novel chimeric proteins, which are very similar to predicted p16/p14ARF chimeric proteins found in other primary cancers, result in maintained p14ARF-p53-p21 signaling while p16-dependent CDK4 inhibition is lost. PMID:24505435

  9. Chimeras of p14ARF and p16: functional hybrids with the ability to arrest growth.

    PubMed

    Williams, Richard T; Barnhill, Lisa M; Kuo, Huan-Hsien; Lin, Wen-Der; Batova, Ayse; Yu, Alice L; Diccianni, Mitchell B

    2014-01-01

    The INK4A locus codes for two independent tumor suppressors, p14ARF and p16/CDKN2A, and is frequently mutated in many cancers. Here we report a novel deletion/substitution from CC to T in the shared exon 2 of p14ARF/p16 in a melanoma cell line. This mutation aligns the reading frames of p14ARF and p16 mid-transcript, producing one protein which is half p14ARF and half p16, chimera ARF (chARF), and another which is half p16 and half non-p14ARF/non-p16 amino acids, p16-Alternate Carboxyl Terminal (p16-ACT). In an effort to understand the cellular impact of this novel mutation and others like it, we expressed the two protein products in a tumor cell line and analyzed common p14ARF and p16 pathways, including the p53/p21 and CDK4/cyclin D1 pathways, as well as the influence of the two proteins on growth and the cell cycle. We report that chARF mimicked wild-type p14ARF by inducing the p53/p21 pathway, inhibiting cell growth through G2/M arrest and maintaining a certain percentage of cells in G1 during nocodazole-induced G2 arrest. chARF also demonstrated p16 activity by binding CDK4. However, rather than preventing cyclin D1 from binding CDK4, chARF stabilized this interaction through p21 which bound CDK4. p16-ACT had no p16-related function as it was unable to inhibit cyclin D1/CDK4 complex formation and was unable to arrest the cell cycle, though it did inhibit colony formation. We conclude that these novel chimeric proteins, which are very similar to predicted p16/p14ARF chimeric proteins found in other primary cancers, result in maintained p14ARF-p53-p21 signaling while p16-dependent CDK4 inhibition is lost.

  10. Copper removal ability by Streptomyces strains with dissimilar growth patterns and endowed with cupric reductase activity.

    PubMed

    Albarracín, Virginia Helena; Avila, Ana Lucía; Amoroso, María Julia; Abate, Carlos Mauricio

    2008-11-01

    Morphological, physiological and molecular characterization of three copper-resistant actinobacterial strains (AB2A, AB3 and AB5A) isolated from copper-polluted sediments of a drainage channel showed that they belonged to the genus Streptomyces. These characteristics plus their distinctive copper resistance phenotypes revealed considerable divergence among the isolates. Highly dissimilar growth patterns and copper removal efficiency were observed for the selected Streptomyces strains grown on minimal medium (MM) added with 0.5 mM of copper sulfate (MM(Cu)). Strain AB2A showed an early mechanism of copper uptake/retention (80% until day 3), followed by a drastic metal efflux process (days 5-7). In contrast, Streptomyces sp. AB3 and AB5A showed only copper retention phenotypes under the same culture conditions. Particularly, Streptomyces sp. AB5A showed a better efficiency in copper removal (94%), although a longer lag phase was observed for this microorganism grown for 7 days in MM(Cu). Cupric reductase activity was detected in both copper-adapted cells and nonadapted cells of all three strains but this activity was up to 100-fold higher in preadapted cells of Streptomyces sp. AB2A. To our knowledge, this is the first time that cupric reductase activity was demonstrated in Streptomyces strains.

  11. Genome Sequencing of a Mung Bean Plant Growth Promoting Strain of P. aeruginosa with Biocontrol Ability

    PubMed Central

    Illakkiam, Devaraj; Shankar, Manoharan; Ponraj, Paramasivan; Rajendhran, Jeyaprakash

    2014-01-01

    Pseudomonas aeruginosa PGPR2 is a mung bean rhizosphere strain that produces secondary metabolites and hydrolytic enzymes contributing to excellent antifungal activity against Macrophomina phaseolina, one of the prevalent fungal pathogens of mung bean. Genome sequencing was performed using the Ion Torrent Personal Genome Machine generating 1,354,732 reads (6,772,433 sequenced bases) achieving ~25-fold coverage of the genome. Reference genome assembly using MIRA 3.4.0 yielded 198 contigs. The draft genome of PGPR2 encoded 6803 open reading frames, of which 5314 were genes with predicted functions, 1489 were genes of known functions, and 80 were RNA-coding genes. Strain specific and core genes of P. aeruginosa PGPR2 that are relevant to rhizospheric habitat were identified by pangenome analysis. Genes involved in plant growth promoting function such as synthesis of ACC deaminase, indole-3-acetic acid, trehalose, mineral scavenging siderophores, hydrogen cyanide, chitinases, acyl homoserine lactones, acetoin, 2,3-butanediol, and phytases were identified. In addition, niche-specific genes such as phosphate solubilising 3-phytase, adhesins, pathway-specific transcriptional regulators, a diguanylate cyclase involved in cellulose synthesis, a receptor for ferrienterochelin, a DEAD/DEAH-box helicase involved in stress tolerance, chemotaxis/motility determinants, an HtpX protease, and enzymes involved in the production of a chromanone derivative with potent antifungal activity were identified. PMID:25184130

  12. Increased rDNA synthesis in germinated conidia of Neurospora crassa is caused by RNA primer molecules found in its culture medium

    SciTech Connect

    Dutta, S.K.; Beljanski, M.

    1984-01-01

    Purine rich small primer RNA molecules (10-15 nucleotides) were isolated from growth medium of germinated (3 hr sprout) conidia of N. crassa. These RNA-primer molecules strongly stimulated in vitro DNA synthesis in N. crassa 74A wild type, as well as in DNAs from mice spleen and lung, and quail testis. These increases of in vitro DNA synthesis was dependent on the concentration of these RNA primer molecules. In contrast, such molecules were not found in 1 or 10 hour sprouts, nor in the culture medium of mycelia (24 hr). These RNA-primer molecules could be hydrolyzed by T1 RNAse but not by pancreatic RNase. Dutta et al. reported increased (250) copies of rRNA genes in germinated conidia (3 hr sprouts) compared to 100 copies of rRNA genes in mycelial cells grown for 24 hours. These observations suggest excessive transcription of rDNAs in the germinated conidial cells which undergo cleavages by nucleates after 3-4 hours of cell growth. Some degradation products were excreted into the culture medium and acted as RNA-primers.

  13. Recombinant fibroblast growth protein enhances healing ability of experimentally induced tendon injury in vivo.

    PubMed

    Oryan, A; Moshiri, A

    2014-06-01

    This study was designed to investigate the effects of recombinant human basic fibroblast growth factor (bFGF) on a complete superficial digital flexor tendon (SDFT) rupture after surgical repair in rabbits. Eighty mature New Zealand White rabbits of both sexes were randomly divided into two equal groups: Treated and Control. Each group was subdivided into two 28- and 84-day post-injury subgroups. After tenotomy and surgical repair, the animals were immobilized for 14 days. In the treated group, bFGF was directly applied subcutaneously over the lesion on days 3, 7 and 10 after injury. The control animals received normal saline injection of the same viscosity and volume and at the same intervals. Ultrasonographical observations were conducted at weekly intervals. The animals were euthanized at 28 and 84 days after injury. The tendons were evaluated at macroscopic, histopathologic and ultrastructural levels and were assessed for biomechanical and percentage dry weight parameters. Compared to injured control animals, treated animals showed a decrease in the diameter of the injured tendon and peritendinous adhesion as well as increased tenoblast proliferation, collagen production and ultimate strength of the injured tendons (p < 0.005). At 84 days after injury, treatment resulted in enhanced maturation of the cellular and collagen elements and improved tissue alignment and density. These improvements resulted in increased biomechanical performance of the injured tendons compared to controls (p = 0.001). bFGF showed promising curative effects on restoration of the biomechanical and morphological properties of the ruptured SDFT in rabbits and may be applicable in clinical studies. Copyright © 2012 John Wiley & Sons, Ltd.

  14. Modestobacter lacusdianchii sp. nov., a Phosphate-Solubilizing Actinobacterium with Ability to Promote Microcystis Growth

    PubMed Central

    Cheng, Juan; Li, Han-Quan; Yang, Jian-Yuan; Zha, Dai-Ming; Zhang, Yu-Qin; Ai, Meng-Jie; Hozzein, Wael N.; Li, Wen-Jun

    2016-01-01

    A novel actinobacterium, designated strain JXJ CY 19T, was isolated from a culture mat of Microcystis aeruginosa FACHB-905 collected from Dianchi Lake, South-west China. 16S rRNA gene sequences comparison of strain JXJ CY 19T and the available sequences in the GenBank database showed that the strain was closely related to Modestobacter marinus 42H12-1T (99.1% similarity) and Modestobacter roseus KLBMP 1279T (99.0%). The isolate had meso-diaminopimelic in the cell wall with whole-cell sugars of mannose, rhamnose, ribose, glucose, galactose, and arabinose. The menaquinone detected was MK-9(H4), while the major cellular fatty acids include C17:1 ω8c, C15:0 iso, C15:1 iso G and C16:0 iso. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The DNA-DNA hybridization values between strains JXJ CY 19T and the closely related type strains Modestobacter marinus CGMCC 4.5581T and Modestobacter roseus NBRC 108673T were determined to be 50.8 ± 0.8% and 44.1 ± 1.7%, respectively. The DNA G+C content was 71.9 mol%. On the basis of the above taxonomic data and differences in physiological characters from the closely related type strains, strain JXJ CY 19T was recognized as a novel species of the genus Modestobacter, for which the name Modestobacter lacusdianchii sp. nov. (JXJ CY 19T = KCTC 39600T = CPCC 204352T) is proposed. The type strain JXJ CY 19T can solubilize calcium phosphate tribasic (Ca3(PO4)2), phytin and L-α-phosphatidylcholine. The phosphate-solubilizing property of the novel actinobacterium could be a possible factor for the increase in growth of Microcystis aeruginosa FACHB-905 in ecosystem where the amount of available soluble phosphate is limited such as Dianchi Lake. PMID:27537546

  15. Maize rhizosphere in Sichuan, China, hosts plant growth promoting Burkholderia cepacia with phosphate solubilizing and antifungal abilities.

    PubMed

    Zhao, Ke; Penttinen, Petri; Zhang, Xiaoping; Ao, Xiaoling; Liu, Maoke; Yu, Xiumei; Chen, Qiang

    2014-01-20

    Plant growth-promoting rhizobacteria promote plant growth by direct and indirect mechanisms. We isolated twelve bacterial strains showing different degrees of phosphate solubilizing activity from maize rhizosphere. Four isolates solubilized over 300 μg mL⁻¹ phosphate from insoluble Ca₃(PO₄)₂, with isolate SCAUK0330 solubilizing over 450 μg mL⁻¹. Based on the 16S rRNA gene sequence analysis SCAUK0330 was identified as Burkholderia cepacia. SCAUK0330 grew at 10-40 °C and pH 4.0-10.0, tolerated up to 5% NaCl, and showed antagonism against nine pathogenic fungi. SCAUK0330 promoted the growth of both healthy and Helminthosporium maydis infected maize plants, indicating that the isolate was a good candidate to be applied as a biofertilizer and a biocontrol agent under a wide range of environmental conditions.The expression of a single SCAUK0330 gene gave E. coli a pH decrease linked ability to solubilize phosphate. The nucleotide and the deduced amino acid sequences of this phosphate solubilization linked gene showed high degree of sequence identity with B. cepacia E37gabY. The production of gluconic acid is considered as the principle mechanism for phosphate solubilization. In agreement with the proposed periplasmic location of the gluconic acid production, the predicted signal peptide and transmembrane regions implied that GabY is membrane bound. Copyright © 2013 Elsevier GmbH. All rights reserved.

  16. Single tracheal inoculation of Aspergillus fumigatus conidia induced aspergillosis in juvenile falcons (Falco spp.).

    PubMed

    Fischer, Dominik; Van Waeyenberghe, Lieven; Failing, Klaus; Martel, An; Lierz, Michael

    2017-09-01

    Aspergillosis is a common and life-threatening respiratory disease in raptors with acute and chronic courses. Among raptors, gyrfalcons (Falco rusticolus) and their hybrids are often declared to be highly susceptible with juvenile individuals being the most susceptible. However, species- and age-specific experimental studies are lacking and minimal infective doses (IDs) for Aspergillus spp. conidia are unknown.Therefore, 8-week-old, healthy gyr-hybrid falcons (F. rusticolus X F. cherrug) (N = 18) were experimentally infected with Aspergillus fumigatus using a single intratracheal inoculation with varying dosages of conidia (10(2) to 10(7) conidia). Over 28 days, clinical signs were monitored as well as haematological and serological parameters. Following euthanasia, necropsy, histopathology, bacteriology, and mycology were performed. Re-isolated fungi were compared to the inoculum using microsatellite length polymorphisms. During the trial, clinical signs and dyspnoea correlated significantly with the ID. Necropsy revealed fungal lesions in the upper and lower airways of 10/18 inoculated falcons, but not in the control birds. In 9/18 inoculated falcons, fungal granulomas were confirmed in histopathology and A. fumigatus was re-isolated from these granulomas. Except one nasal isolate all re-isolated fungal strains were identical to the inoculum strain. Based on mycology and histopathology a minimal ID of 50% was calculated to be MID50% (±S.E.) = 10(4.52±0.67) for a single tracheal inoculation of A. fumigatus conidia. This study demonstrates for the first time that a single exposure is able to cause acute aspergillosis in juvenile falcons.

  17. In vitro photodynamic inactivation of conidia of the phytopathogenic fungus Colletotrichum graminicola with cationic porphyrins.

    PubMed

    Vandresen, Camila Chevonica; Gonçalves, Alan Guilherme; Ducatti, Diogo Ricardo Bazan; Murakami, Fabio Seigi; Noseda, Miguel Daniel; Duarte, Maria Eugenia Rabello; Barreira, Sandra Mara Woranovicz

    2016-05-11

    Photodynamic inactivation (PDI) is an efficient approach for the elimination of a series of microorganisms; however, PDI involving phytopathogenic filamentous fungi is scarce in the literature. In the present study, we have demonstrated the photoinactivating properties of five cationic meso-(1-methyl-4-pyridinio)porphyrins on conidia of the phytopathogen Colletotrichum graminicola. For this purpose, photophysical properties (photostability and (1)O2 singlet production) of the porphyrins under study were first evaluated. PDI assays were then performed with a fluence of 30, 60, 90 and 120 J cm(-2) and varying the porphyrin concentration from 1 to 25 μmol L(-1). Considering the lowest concentration that enabled the best photoinactivation, with the respective lowest effective irradiation time, the meso-(1-methyl-4-pyridinio)porphyrins herein studied could be ranked as follows: triple-charged 4 (1 μmol L(-1) with a fluence of 30 J cm(-2)) > double-charged-trans2 (1 μmol L(-1) with 60 J cm(-2)) > tetra-charged 5 (15 μmol L(-1) with 90 J cm(-2)) > mono-charged 1 (25 μmol L(-1) with 120 J cm(-2)). Double-charged-cis-porphyrin 3 inactivated C. graminicola conidia in the absence of light. Evaluation of the porphyrin binding to the conidia and fluorescence microscopic analysis were also performed, which were in agreement with the PDI results. In conclusion, the cationic porphyrins herein studied were considered efficient photosensitizers to inactivate C. graminicola conidia. The amount and position of positive charges are related to the compounds' amphiphilicity and therefore to their photodynamic activity.

  18. Lag time for germination of Penicillium chrysogenum conidia is induced by temperature shifts.

    PubMed

    Kalai, Safaa; Bensoussan, Maurice; Dantigny, Philippe

    2014-09-01

    In the environment, fungal conidia are subject to transient conditions. In particular, temperature is varying according to day/night periods. All predictive models for germination assume that fungal spores can adapt instantaneously to changes of temperature. The only study that supports this assumption (Gougouli and Koutsoumanis, 2012, Modelling germination of fungal spores at constant and fluctuating temperature conditions. International Journal of Food Microbiology, 152: 153-161) was carried out on Penicillium expansum and Aspergillus niger conidia that, in most cases, already produced germ tubes. In contrast, the present study focuses on temperature shifts applied during the first stages of germination (i.e., before the apparition of the germ tubes). Firstly, germination times were determined in steady state conditions at 10, 15, 20 and 25 °C. Secondly, temperature shifts (e.g., up-shifts and down-shifts) were applied at 1/4, 1/2, and 3/4 of germination times, with 5, 10 and 15 °C magnitudes. Experiments were carried out in triplicate on Penicillium chrysogenum conidia on Potato Dextrose Agar medium according to a full factorial design. Statistical analysis of the results clearly demonstrated that the assumption of instantaneous adaptation of the conidia should be rejected. Temperature shifts during germination led to an induced lag time or an extended germination time as compared to the experiments conducted ay steady state. The induced lag time was maximized when the amplitude of the shift was equal to 10 °C. Interaction between the instant and the direction of the shift was highlighted. A negative lag time was observed for a 15 °C down-shift applied at 1/4 of the germination time. This result suggested that at optimal temperature the rate of germination decreased with time, and that the variation of this rate with time depended on temperature.

  19. Interleukin-18 augments growth ability of primary human melanocytes by PTEN inactivation through the AKT/NF-κB pathway.

    PubMed

    Zhou, Jia; Shang, Jing; Song, Jing; Ping, Fengfeng

    2013-02-01

    Normal human skin relies on melanocytes to provide photoprotection and thermoregulation by producing melanin. The growth and behavior of melanocytes are controlled by many factors. Interleukin-18 (IL-18) is expressed in both immune and non-immune cells and participates in the adjustment of multitude cellular functions. Nonetheless, the regulative roles of IL-18 in melanogenesis and growth of melanocytes have not been explored. The present study was conducted to investigate the effects of IL-18 on melanocytes and elucidate the underlying mechanisms. We proved that IL-18 increased the tyrosinase activity and melanin content in normal human foreskin-derived epidermal melanocytes (NHEM). Treatment with IL-18 (20 ng/ml) enhanced the expression of c-Kit, microphtalmia-associated transcription factor (MITF) and its downstream tyrosinase-related protein 1 (TRP-1), and TRP-2. In addition, IL-18 induced NHEM migration at concentration of 20 ng/ml. These results indicated a promotive action of IL-18 on melanogenesis in NHEM. Our data revealed that IL-18 stimulated ERK1/2 and NF-κB activation, improved p-Akt, p70 S6K and anti-apoptotic Bcl-2 levels, and deactivated phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in NHEM. Besides, IL-18 increased level of PTEN phosphorylation to protect NHEM from damage induced by H(2)O(2). These results in vitro showed the accommodation of IL-18 in melanocytes growth. Therefore, we suggested an important regulating action of IL-18 to melanogenesis and cell growth ability of skin melanocytes.

  20. EVALUATION OF DIFFERENT METHODS FOR THE EXTRACTION OF DNA FROM FUNGAL CONIDIA BY QUANTITATIVE COMPETITIVE PCR ANALYSIS

    EPA Science Inventory

    Five different DNA extraction methods were evaluated for their effectiveness in recovering PCR templates from the conidia of a series of fungal species often encountered in indoor air. The test organisms were Aspergillus versicolor, Penicillium chrysogenum, Stachybotrys chartaru...

  1. EVALUATION OF DIFFERENT METHODS FOR THE EXTRACTION OF DNA FROM FUNGAL CONIDIA BY QUANTITATIVE COMPETITIVE PCR ANALYSIS

    EPA Science Inventory

    Five different DNA extraction methods were evaluated for their effectiveness in recovering PCR templates from the conidia of a series of fungal species often encountered in indoor air. The test organisms were Aspergillus versicolor, Penicillium chrysogenum, Stachybotrys chartaru...

  2. Development of pulmonary fibrosis in mice during infection with Paracoccidioides brasiliensis conidia.

    PubMed

    Restrepo, S; Tobon, A; Trujillo, J; Restrepo, A

    1992-01-01

    Pulmonary fibrosis is a feared sequelae of paracoccidioidomycosis. We sought to determine if mice exposed to Paracoccidioides brasiliensis conidia would develop pulmonary fibrosis. BALB/c mice were infected intranasally with P. brasiliensis conidia and sacrificed at regular intervals. One lung was sectioned for histopathology and sections were stained with haematoxylin and eosin, trichromic and argentic stains; the other lung was homogenized and cultured to determine the viability of the fungus. One week post-challenge, only small peribronchial foci were apparent. After 4 weeks, reticular fibres appeared disorganized and disrupted. Six to 8 weeks later peribronchial infiltrates were larger and appeared surrounded by reticular fibres; thick collagen I fibres were noticed in the infiltrated areas at this time. On weeks 10-12, infiltrates were confluent and reticular fibres were concentrated around the inflammatory foci; collagenization was apparent. Observations up to 16 weeks revealed diffuse involvement of the lung parenchyma with extensive collagenization. Lung cultures were always positive. We suggest that inhalation of P. brasiliensis conidia induces adverse lung responses leading to changes in the proportion of collagen fibres I and III.

  3. Effects of fluctuating moisture and temperature regimes on the persistence of quiescent conidia of Isaria fumosorosea.

    PubMed

    Bouamama, N; Vidal, C; Fargues, J

    2010-10-01

    Conidia of Isaria fumosorosea were submitted to three regimes of temperature and moisture to simulate microclimatic conditions which prevail in temperate (43% RH and 28 degrees C to 98% RH and 15 degrees C), subtropical (75% RH and 35 degrees C to 98% RH and 25 degrees C), and arid areas (13% RH and 40 degrees C to 33% RH and 15 degrees C) with daily fluctuating cycles. Germination, conidial viability, and virulence to Spodoptera frugiperda larvae were less affected after 20 days exposure under temperate cycling conditions than under arid and subtropical conditions. Exposure of conidia for 20 days to constant nocturnal simulated conditions of any tested regime weakly affected conidial persistence, whereas diurnal conditions exerted the most detrimental effects of high temperatures. However, when tested at both 45 degrees C and 50 degrees C at 33% RH for 160 h, the persistence of I. fumosorosea conidia was relatively higher than expected. These results emphasize that climatic conditions prevailing in environments and ecological fitness of fungal isolates have to be taken into account for assessing microbial control strategies.

  4. Fungal tyrosine betaine, a novel secondary metabolite from conidia of entomopathogenic Metarhizium spp. fungi.

    PubMed

    Carollo, Carlos A; Calil, Ana Luiza A; Schiave, Letícia A; Guaratini, Thais; Roberts, Donald W; Lopes, Norberto P; Braga, Gilberto U L

    2010-01-01

    Fungi, including the entomopathogenic deuteromycete Metarhizium anisopliae, produce a wide diversity of secondary metabolites that either can be secreted or stored in specific developmental structures, e.g., conidia. Some secondary metabolites, such as pigments, polyols and mycosporines, are associated with pathogenicity and/or fungal tolerance to several stress-inducing environmental factors, including temperature and solar radiation extremes. Extracts of M. anisopliae var. anisopliae (strain ESALQ-1037) conidia were purified by chromatographic procedures and the isolated compounds analyzed by ¹H and ¹³C nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. LC-MS analyses were carried out to search for mycosporines (the initial targets), but no compounds of this class were detected. A molecule whose natural occurrence was previously undescribed was identified. It consists of betaine conjugated with tyrosine, and the structure was identified as 2-{[1-carboxy-2-(4-hydroxyphenyl)ethyl]amino}-N,N,N-trimethyl-2-oxoethanammonium. Mannitol was the predominant compound in the alcoholic conidial extract, but no amino acids other than tyrosine were found to be conjugated with betaine in conidia. The fungal tyrosine betaine was detected also in conidial extracts of three other M. anisopliae var. anisopliae (ARSEF 1095, 5626 and 5749) and three M. anisopliae var. acridum isolates (ARSEF 324, 3391 and 7486), but it was not detected in Aspergillus nidulans conidial extract (ATCC 10074).

  5. Elevated ability to compete for limited food resources by 'all-fish' growth hormone transgenic common carp Cyprinus carpio.

    PubMed

    Duan, M; Zhang, T; Hu, W; Sundström, L F; Wang, Y; Li, Z; Zhu, Z

    2009-10-01

    Food consumption, number of movements and feeding hierarchy of juvenile transgenic common carp Cyprinus carpio and their size-matched non-transgenic conspecifics were measured under conditions of limited food supply. Transgenic fish exhibited 73.3% more movements as well as a higher feeding order, and consumed 1.86 times as many food pellets as their non-transgenic counterparts. After the 10 day experiment, transgenic C. carpio had still not realized their higher growth potential, which may be partly explained by the higher frequency of movements of transgenics and the 'sneaky' feeding strategy used by the non-transgenics. The results indicate that these transgenic fish possess an elevated ability to compete for limited food resources, which could be advantageous after an escape into the wild. It may be that other factors in the natural environment (i.e. predation risk and food distribution), however, would offset this advantage. Thus, these results need to be assessed with caution.

  6. Ability of Group IVB metallocene polyethers containing dienestrol to arrest the growth of selected cancer cell lines

    PubMed Central

    2009-01-01

    Background Monomeric Group IVB (Ti, Zr and Hf) metallocenes represent a new class of antitumor compounds. There is literature on the general biological activities of some organotin compounds. Unfortunately, there is little information with respect to the molecular level activity of these organotin compounds. We recently started focusing on the anti-cancer activity of organotin polymers that we had made for other purposes and as part of our platinum anti-cancer effort. Methods For this study, we synthesized a new series of metallocene-containing compounds coupling the metallocene unit with dienestrol, a synthetic, nonsteroidal estrogen. This is part of our effort to couple known moieties that offer antitumor activity with biologically active units hoping to increase the biological activity of the combination. The materials were confirmed to be polymeric using light scattering photometry and the structural repeat unit was verified employing matrix assisted laser desorption ionization mass spectrometry and infrared spectroscopy results. Results The polymers demonstrated the ability to suppress the growth of a series of tumor cell lines originating from breast, colon, prostrate, and lung cancers at concentrations generally lower than those required for inhibition of cell growth by the commonly used antitumor drug cisplatin. Conclusion These drugs show great promise in vitro against a number of cancer cell lines and due to their polymeric nature will most likely be less toxic than currently used metal-containing drugs such as cisplatin. These drugs also offer several addition positive aspects. First, the reactants are commercially available so that additional synthetic steps are not needed. Second, synthesis of the polymer is rapid, occurring within about 15 seconds. Third, the interfacial synthetic system is already industrially employed in the synthesis of aromatic nylons and polycarbonates. Thus, the ability to synthesize large amounts of the drugs is straight

  7. Growth and Survival of Mesorhizobium loti Inside Acanthamoeba Enhanced Its Ability to Develop More Nodules on Lotus corniculatus.

    PubMed

    Karaś, Magdalena A; Turska-Szewczuk, Anna; Trapska, Dominika; Urbanik-Sypniewska, Teresa

    2015-08-01

    The importance of protozoa as environmental reservoirs of pathogens is well recognized, while their impact on survival and symbiotic properties of rhizobia has not been explored. The possible survival of free-living rhizobia inside amoebae could influence bacterial abundance in the rhizosphere of legume plants and the nodulation competitiveness of microsymbionts. Two well-characterized strains of Mesorhizobium: Mesorhizobium loti NZP2213 and Mesorhizobium huakuii symbiovar loti MAFF303099 were assayed for their growth ability within the Neff strain of Acanthamoeba castellanii. Although the association ability and the initial uptake rate of both strains were similar, recovery of viable M. huakuii MAFF303099 after 4 h postinfection decreased markedly and that of M. loti NZP2213 increased. The latter strain was also able to survive prolonged co-incubation within amoebae and to self-release from the amoeba cell. The temperature 28 °C and PBS were established as optimal for the uptake of Mesorhizobium by amoebae. The internalization of mesorhizobia was mediated by the mannose-dependent receptor. M. loti NZP2213 bacteria released from amoebae developed 1.5 times more nodules on Lotus corniculatus than bacteria cultivated in an amoebae-free medium.

  8. Transforming Growth Factor-β1 and Cigarette Smoke Inhibit the Ability of β2-Agonists to Enhance Epithelial Permeability

    PubMed Central

    Ivonnet, Pedro; Dennis, John S.; Conner, Gregory E.; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl− and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist–mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air–liquid interface, were used for 14C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist–mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist–mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist–mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in

  9. Transforming growth factor-β1 and cigarette smoke inhibit the ability of β2-agonists to enhance epithelial permeability.

    PubMed

    Unwalla, Hoshang J; Ivonnet, Pedro; Dennis, John S; Conner, Gregory E; Salathe, Matthias

    2015-01-01

    Chronic bronchitis, caused by cigarette smoke exposure, is characterized by mucus hypersecretion and reduced mucociliary clearance (MCC). Effective MCC depends, in part, on adequate airway surface liquid. Cystic fibrosis transmembrane conductance regulator (CFTR) provides the necessary osmotic gradient for serosal to mucosal fluid transport through its ability to both secrete Cl(-) and regulate paracellular permeability, but CFTR activity is attenuated in chronic bronchitis and in smokers. β2-adrenergic receptor (β2-AR) agonists are widely used for managing chronic obstructive pulmonary disease, and can activate CFTR, stimulate ciliary beat frequency, and increase epithelial permeability, thereby stimulating MCC. Patients with chronic airway diseases and cigarette smokers demonstrate increased transforming growth factor (TGF)-β1 signaling, which suppresses β2-agonist-mediated CFTR activation and epithelial permeability increases. Restoring CFTR function in these diseases can restore the ability of β2-agonists to enhance epithelial permeability. Human bronchial epithelial cells, fully redifferentiated at the air-liquid interface, were used for (14)C mannitol flux measurements, Ussing chamber experiments, and quantitative RT-PCR. β2-agonists enhance epithelial permeability by activating CFTR via the β2-AR/adenylyl cyclase/cAMP/protein kinase A pathway. TGF-β1 inhibits β2-agonist-mediated CFTR activation and epithelial permeability enhancement. Although TGF-β1 down-regulates both β2-AR and CFTR mRNA, functionally it only decreases CFTR activity. Cigarette smoke exposure inhibits β2-agonist-mediated epithelial permeability increases, an effect reversed by blocking TGF-β signaling. β2-agonists enhance epithelial permeability via CFTR activation. TGF-β1 signaling inhibits β2-agonist-mediated CFTR activation and subsequent increased epithelial permeability, potentially limiting the ability of β2-agonists to facilitate paracellular transport in disease

  10. Insulin-like growth factor I signaling for brain recovery and exercise ability in brain ischemic rats.

    PubMed

    Chang, Heng-Chih; Yang, Yea-Ru; Wang, Paulus S; Kuo, Chia-Hua; Wang, Ray-Yau

    2011-12-01

    Exercise increases neuron survival and plasticity in the adult brain by enhancing the uptake of insulin-like growth factor I (IGF-I). Exercise also reduces the infarct volume in the ischemic brain and improves motor function after such a brain insult. However, the underlying mechanisms are not fully known. The purpose of this study was to investigate the involvement of IGF-I signaling in neuroprotection after exercise. Rats were assigned to one of four groups: middle cerebral artery occlusion (MCAO) without exercise training (MC), MCAO with exercise training (ME), MCAO with IGF-I receptor inhibitor and without exercise training (MAg), and MCAO with IGF-I receptor inhibitor and exercise training (MEAg). Rats in the ME and MEAg groups underwent treadmill training for 14 d, and rats in the MC and MAg groups served as controls. After the final intervention, rats were sacrificed under anesthesia, and samples were collected from the affected motor cortex, striatum, and plasma. IGF-I and p-Akt levels in the affected motor cortex and the striatum of the ME group were significantly higher than those in the MC group, with significant decreases in infarct volume and improvements in motor function. However, IGF-I receptor inhibitor eliminated these effects and decreased the exercise ability. The brain IGF-I signaling strongly correlated with exercise ability. Exercise-enhanced IGF-I entrance into ischemic brain and IGF-I signaling was related to exercise-mediated neuroprotection. IGF-1 signaling also affected the ability to exercise after brain ischemia.

  11. Production and quality of conidia by Metarhizium anisopliae var. lepidiotum: critical oxygen level and period of mycelium competence.

    PubMed

    Garcia-Ortiz, Nohemi; Tlecuitl-Beristain, Saúl; Favela-Torres, Ernesto; Loera, Octavio

    2015-03-01

    Mycoinsecticides application within Integral Pest Management requires high quantities of conidia, with the proper quality and resistance against environmental conditions. Metarhizium anisopliae var. lepidiotum conidia were produced in normal atmospheric conditions (21 % O2) and different concentrations of oxygen pulses (16, 26, 30, and 40 %); conidia obtained under hypoxic conditions showed significantly lower viability, hydrophobicity, and virulence against Tenebrio molitor larvae or mealworm, compared with those obtained under normal atmospheric conditions. Higher concentrations of oxygen (26 and 30 %) improved conidial production. However, when a 30 % oxygen concentration was applied, maximal conidial yields were obtained at earlier times (132 h) relative to 26 % oxygen pulses (156 h); additionally, with 30 % oxygen pulses, conidia thermotolerance was improved, maintaining viability, hydrophobicity, and virulence. Although conidial production was not affected when 40 % oxygen pulses were applied, viability and virulence were diminished in those conidia. In order to find a critical time for mycelia competence to respond to these oxidant conditions, oxygen pulses were first applied either at 36, 48, 60, and 72 h. A critical time of 60 h was determined to be the best time for the M. anisopliae var. lepidiotum mycelia to respond to oxygen pulses in order to increase conidial production and also to maintain the quality features. Therefore, oxygen-enriched (30 %) pulses starting at 60 h are recommended for a high production without the impairment of quality of M. anisopliae var. lepidiotum conidia.

  12. Effection of Ocneridia volxemi Bolivar (Pamphaginae, Orthoptera) hoppers and adults by Beauveria bassiana (Deuteromycotina, hyphomycetes) conidia in an oil formulation.

    PubMed

    Bounechada, M; Doumandji, S E

    2004-01-01

    Ocneridia volxemi Bolivar (Pamphaginae, Orthoptera) is one of the important insects pest in the heigh plains of north east of Algeria. Larval and adult stages caused severe damage to the leaves of cereals and an other various crops. Laboratory studies were conducted to the determine the potential of the fungus Beauveria bassiana for the control of the pest of larval and adults. Positive results were obtaved when larvae and adults were sprayed with different concentration of fungus conidia (D1: 2 x 10(6) conidia/ml, D2: 5 x 10(5) conidia/ml, D3: 8 x 10(4) conidia/ml, D4: 10(2) conidia/ml). Concentration at D1 and D2 in an oil formulation showed respectively 100% and 90 % larval mortality at the first day of treatment and 100%-9% adults mortality at the five day of treatement. The results revealed that the rates of infection and mortality were significantly related to the concentration of conidia in the corresponding samples. Beauveria bassiana can be considerd as a promising biocontrol agents of Ocneridia volxemi may be an other locuts, but field experimentation is necessary to subtantiate these finding.

  13. Liquid culture production of microsclerotia and submerged conidia by Trichoderma harzianum active against damping-off disease caused by Rhizoctonia solani.

    PubMed

    Kobori, Nilce N; Mascarin, Gabriel M; Jackson, Mark A; Schisler, David A

    2015-04-01

    Media and culturing protocols were identified that supported the formation of submerged conidia and microsclerotia (MS) by Trichoderma harzianum Rifai strain T-22 using liquid culture fermentation. Liquid media with a higher carbon concentration (36 g L(-1)) promoted MS formation at all C:N ratios tested. Hyphae aggregated to form MS after 2 d growth and after 7 d MS were fully melanized. This is the first report of MS formation by T. harzianum or any species of Trichoderma. Furthermore, submerged conidia formation was induced by liquid culture media, but yields, desiccation tolerance, and storage stability varied with C:N ratio and carbon rate. Air-dried MS granules (<4% moisture) retained excellent shelf life under cool and unrefrigerated storage conditions with no loss in conidial production. A low-cost complex nitrogen source based on cottonseed flour effectively supported high MS yields. Amending potting mix with dried MS formulations reduced or eliminated damping-off of melon seedlings caused by Rhizoctonia solani. Together, the results provide insights into the liquid culture production, stabilization process, and bioefficacy of the hitherto unreported MS of T. harzianum as a potential biofungicide for use in integrated management programs against soilborne diseases.

  14. Elevated CO2 impacts bell pepper growth with consequences to Myzus persicae life history, feeding behaviour and virus transmission ability.

    PubMed

    Dáder, Beatriz; Fereres, Alberto; Moreno, Aránzazu; Trębicki, Piotr

    2016-01-08

    Increasing atmospheric carbon dioxide (CO2) impacts plant growth and metabolism. Indirectly, the performance and feeding of insects is affected by plant nutritional quality and resistance traits. Life history and feeding behaviour of Myzus persicae were studied on pepper plants under ambient (aCO2, 400 ppm) or elevated CO2 (eCO2, 650 ppm), as well as the direct impact on plant growth and leaf chemistry. Plant parameters were significantly altered by eCO2 with a negative impact on aphid's life history. Their pre-reproductive period was 11% longer and fecundity decreased by 37%. Peppers fixed significantly less nitrogen, which explains the poor aphid performance. Plants were taller and had higher biomass and canopy temperature. There was decreased aphid salivation into sieve elements, but no differences in phloem ingestion, indicating that the diminished fitness could be due to poorer tissue quality and unfavourable C:N balance, and that eCO2 was not a factor impeding feeding. Aphid ability to transmit Cucumber mosaic virus (CMV) was studied by exposing source and receptor plants to ambient (427 ppm) or elevated (612 ppm) CO2 before or after virus inoculation. A two-fold decrease on transmission was observed when receptor plants were exposed to eCO2 before aphid inoculation when compared to aCO2.

  15. Elevated CO2 impacts bell pepper growth with consequences to Myzus persicae life history, feeding behaviour and virus transmission ability

    NASA Astrophysics Data System (ADS)

    Dáder, Beatriz; Fereres, Alberto; Moreno, Aránzazu; Trębicki, Piotr

    2016-01-01

    Increasing atmospheric carbon dioxide (CO2) impacts plant growth and metabolism. Indirectly, the performance and feeding of insects is affected by plant nutritional quality and resistance traits. Life history and feeding behaviour of Myzus persicae were studied on pepper plants under ambient (aCO2, 400 ppm) or elevated CO2 (eCO2, 650 ppm), as well as the direct impact on plant growth and leaf chemistry. Plant parameters were significantly altered by eCO2 with a negative impact on aphid’s life history. Their pre-reproductive period was 11% longer and fecundity decreased by 37%. Peppers fixed significantly less nitrogen, which explains the poor aphid performance. Plants were taller and had higher biomass and canopy temperature. There was decreased aphid salivation into sieve elements, but no differences in phloem ingestion, indicating that the diminished fitness could be due to poorer tissue quality and unfavourable C:N balance, and that eCO2 was not a factor impeding feeding. Aphid ability to transmit Cucumber mosaic virus (CMV) was studied by exposing source and receptor plants to ambient (427 ppm) or elevated (612 ppm) CO2 before or after virus inoculation. A two-fold decrease on transmission was observed when receptor plants were exposed to eCO2 before aphid inoculation when compared to aCO2.

  16. Elevated CO2 impacts bell pepper growth with consequences to Myzus persicae life history, feeding behaviour and virus transmission ability

    PubMed Central

    Dáder, Beatriz; Fereres, Alberto; Moreno, Aránzazu; Trębicki, Piotr

    2016-01-01

    Increasing atmospheric carbon dioxide (CO2) impacts plant growth and metabolism. Indirectly, the performance and feeding of insects is affected by plant nutritional quality and resistance traits. Life history and feeding behaviour of Myzus persicae were studied on pepper plants under ambient (aCO2, 400 ppm) or elevated CO2 (eCO2, 650 ppm), as well as the direct impact on plant growth and leaf chemistry. Plant parameters were significantly altered by eCO2 with a negative impact on aphid’s life history. Their pre-reproductive period was 11% longer and fecundity decreased by 37%. Peppers fixed significantly less nitrogen, which explains the poor aphid performance. Plants were taller and had higher biomass and canopy temperature. There was decreased aphid salivation into sieve elements, but no differences in phloem ingestion, indicating that the diminished fitness could be due to poorer tissue quality and unfavourable C:N balance, and that eCO2 was not a factor impeding feeding. Aphid ability to transmit Cucumber mosaic virus (CMV) was studied by exposing source and receptor plants to ambient (427 ppm) or elevated (612 ppm) CO2 before or after virus inoculation. A two-fold decrease on transmission was observed when receptor plants were exposed to eCO2 before aphid inoculation when compared to aCO2. PMID:26743585

  17. The role of the SDF-1/ CXCR7 axis on the growth and invasion ability of endometrial cancer cells.

    PubMed

    Gu, Hong-Qin; Zhang, Zhen-Bo; Zhang, Jia-Wen; Wang, Qian-Qian; Xi, Xiao-Wei; He, Yin-Yan

    2017-04-01

    Stroma-derived factor-1 (SDF-1) and its receptor C-X-C chemokine receptor-4 (CXCR4) are involved in human endometrial carcinoma (EC) progression. CXCR7 is another important receptor of SDF-1 and has a higher affinity with SDF-1 compared with that of CXCR4. This paper aims to study the effects of the SDF-1/CXCR7 axis on the growth and invasion ability of EC cells. CXCR7 expression was evaluated by quantitative RT-PCR, immunohistochemistry, immunocytochemistry and Western blotting in EC cell lines and 30 cases of primary EC tissue from patients. EC cell line proliferation and migration were assessed following knockdown of CXCR7 by MTT and transwell assays. The results showed that CXCR7 was highly expressed at both mRNA and protein levels in the EC cells and tissue. siCXCR7 effectively silenced CXCR7 in Ishikawa and AN3CA cells. Treatment with 17β-oestradiol (17β-E2) significantly increased the levels of CXCR7 and SDF-1 in Con, siCon and siCXCR7 treated Ishikawa. siCXCR7 persistently inhibited CXCR7 expression, even in cells treated with 17β-E2. Moreover, in vitro functional analyses, silencing CXCR7 resulted in decreased proliferation in Ishikawa and AN3CA cells. Treatment with 17β-E2 and SDF-1 significantly promoted the growth and migration in siCon treated Ishikawa and AN3CA. Interestingly, in response to 17β-E2 and SDF-1 stimulation, siCXCR7 continuously inhibited the growth and invasion of Ishikawa and AN3CA cells. Our results indicate that SDF-1/CXCR7 plays a positive role in the proliferation and invasion of EC cells. CXCR7 inhibition treatment may provide a promising strategy for anti-tumour therapy for EC.

  18. Monocyte-derived dendritic cells from patients with dermatophytosis restrict the growth of Trichophyton rubrum and induce CD4-T cell activation.

    PubMed

    Santiago, Karla; Bomfim, Gisele Facholi; Criado, Paulo Ricardo; Almeida, Sandro Rogerio

    2014-01-01

    Dermatophytes are the most common agents of superficial mycoses that are caused by mold fungi. Trichophyton rubrum is the most common pathogen causing dermatophytosis. The immunology of dermatophytosis is currently poorly understood. Recently, our group investigated the interaction of T. rubrum conidia with peritoneal mouse macrophages. We found that macrophages phagocytose T. rubrum conidia resulted in a down-modulation of class II major histocompatibility complex (MHC) antigens and in the expression of co-stimulatory molecules. Furthermore, it induced the production of IL-10, and T. rubrum conidia differentiated into hyphae that grew and killed the macrophages after 8 hrs of culture. This work demonstrated that dendritic cells (DCs) and macrophages, from patients or normal individuals, avidly interact with pathogenic fungus T. rubrum. The dermatophyte has two major receptors on human monocyte-derived DC: DC-SIGN and mannose receptor. In contrast macrophage has only mannose receptor that participates in the phagocytosis or bound process. Another striking aspect of this study is that unlike macrophages that permit rapid growth of T. rubrum, human DC inhibited the growth and induces Th activation. The ability of DC from patients to interact and kill T. rubrum and to present Ags to T cells suggests that DC may play an important role in the host response to T. rubrum infection by coordinating the development of cellular immune response.

  19. Use of a granular bioplastic formulation for carrying conidia of a non-aflatoxigenic strain of Aspergillus flavus.

    PubMed

    Accinelli, Cesare; Saccà, M Ludovica; Abbas, Hamed K; Zablotowicz, Robert M; Wilkinson, Jeffery R

    2009-09-01

    Previous research demonstrated that aflatoxin contamination in corn is reduced by field application of wheat grains pre-inoculated with the non-aflatoxigenic Aspergillus flavus strain NRRL 30797. To facilitate field applications of this biocontrol isolate, a series of laboratory studies were conducted on the reliability and efficiency of replacing wheat grains with the novel bioplastic formulation Mater-Bi to serve as a carrier matrix to formulate this fungus. Mater-Bi granules were inoculated with a conidial suspension of NRRL 30797 to achieve a final cell density of approximately log 7 conidia/granule. Incubation of 20-g soil samples receiving a single Mater-Bi granule for 60-days resulted in log 4.2-5.3 propagules of A. flavus/g soil in microbiologically active and sterilized soil, respectively. Increasing the number of granules had no effect on the degree of soil colonization by the biocontrol fungus. In addition to the maintenance of rapid vegetative growth and colonization of soil samples, the bioplastic formulation was highly stable, indicating that Mater-Bi is a suitable substitute for biocontrol applications of A. flavus NRRL 30797.

  20. Phytohormone production endowed with antagonistic potential and plant growth promoting abilities of culturable endophytic bacteria isolated from Clerodendrum colebrookianum Walp.

    PubMed

    Passari, Ajit Kumar; Mishra, Vineet Kumar; Leo, Vincent Vineeth; Gupta, Vijai Kumar; Singh, Bhim Pratap

    2016-12-01

    In this study, culturable endophytic bacterial isolates obtained from an ethnomedicinal plant Clerodendrum colebrookianum Walp., were assessed for their diversity, in vitro screening for their plant growth promoting (PGP) activities and to use them as inoculant for in vivo PGP activities with biocontrol potential. Totally, 73 isolates were recovered from different tissues of C. colebrookianum were identified by 16S rRNA gene sequencing and phylogenetically analyzed by using BOX-PCR fingerprinting. Out of 73 isolates, 52 exhibited varying extents of antagonistic potential were selected for screening for various PGP traits. Concerning the PGP activities, the percentage of isolates positive for P-solubilisation, indolic compounds production, siderophore and ammonia production were 84.6, 92.3, 78.8 and 98.0 respectively. All isolates were positive for the production of hydrocyanic acid (HCN) and 86.5%, 84.6% and 90.3% of isolates showed significant cellulase, amylase and protease production respectively. Further, the top 10 bacterial isolates based on a bonitur scale with multiple PGP activities were screened for root surface colonization and biofilm formation ability. Out of selected 10 isolates, 9 showed significant potential for root surface colonization on tomato roots. Isolate BPSAC6 identified as Bacillus sp. was most efficient in biofilm formation as assessed with respect to the intensity of crystal violet, which further showed their potential to withstand various biotic and abiotic stresses. Furthermore, Bacillus sp. strain BPSAC6 showed a significant increase in shoot and root height as well as fresh weight after 45 and 60 d of inoculation with tomato seedlings. Additionally, biosynthetic potential of antagonistic isolate was detection by using PKSI, PKSII and NRPS biosynthetic genes. Two isolates Pseudomonas psychrotolerans and Labrys wisconsinensis were reported first time as an endophyte. At last, first time an endophytic bacterial strain Bacillus sp. BPSAC

  1. Contact between dermal papilla cells and dermal sheath cells enhances the ability of DPCs to induce hair growth.

    PubMed

    Yamao, Mikaru; Inamatsu, Mutsumi; Ogawa, Yuko; Toki, Hiroshi; Okada, Taro; Toyoshima, Koh-ei; Yoshizato, Katsutoshi

    2010-12-01

    We previously showed that cultured rat dermal papilla cells (DPCs) retain their hair-inducing capacity on afollicular epidermal cell (EPCs). Here, we examined the hair growth-inducing capacity of differently subcultured DPCs by transplanting them, along with rat EPCs, onto the backs of nude mice (graft chamber assay). DPCs at passage (p) 6 (DPCs(p6) or, more generally, low-passage DPCs) induced hair formation. However, DPCs(p>30) (high-passage DPCs) had no such activity and induced only subepidermal hair follicles (HFs) that were not encapsulated by the dermal sheath (DS). Thus, we examined the effect of DS cells (DSCs(p=1)) on the ability of DPCs(p=60) to induce hair growth by testing a mixture of these two cell types (cotransplant) in the graft chamber assay, in which DSCs(p=1) and DPCs(p=60) were labeled with enhanced green fluorescent protein (EGFP) and 1,1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI), respectively. These cotransplants generated hairs as actively as did DPCs(p=6) transplants. Their HFs were encapsulated with EGFP(+)-DS and had DPs consisting largely of EGFP(+)-DPCs (47%) and DiI(+)-DPCs (43%), indicating a major contribution of DSC(p=1)-derived DPCs to HF induction. In addition, the results of in vitro coculture of DPCs(p=60) and DSCs(p=1) suggest that high-passage DPCs stimulate the expression of certain trichogenic genes in DSCs.

  2. The Membrane-anchoring Domain of Epidermal Growth Factor Receptor Ligands Dictates Their Ability to Operate in Juxtacrine Mode

    SciTech Connect

    Dong, Jianying; Opresko, Lee; Chrisler, William B.; Orr, Galya; Quesenberry, Ryan D.; Lauffenburger, Douglas A.; Wiley, H S.

    2005-06-01

    All ligands of the epidermal growth factor receptor (EGFR) are synthesized as membrane-anchored precursors. Previous work has suggested that some ligands, such as EGF, must be proteolytically released to be active, whereas others, such as heparin binding EGF-like growth factor (HB-EGF) can function while still anchored to the membrane (i.e., juxtacrine signaling). To explore the structural basis for these differences in ligand activity, we engineered a series of membrane-anchored ligands in which the core, receptor-binding domain of EGF was combined with different domains of both EGF and HB-EGF. We found that ligands having the N-terminal extension of EGF could not bind to the EGFR, even when released from the membrane. Ligands lacking an N-terminal extension, but possessing the membrane-anchoring domain of EGF still required proteolytic release for activity, whereas ligands with the membrane anchoring domain of HB-EGF could elicit full biological activity while still membrane anchored. Ligands containing the HB-EGF membrane anchor, but lacking an N-terminal extension, activated EGFR during their transit through the Golgi apparatus . However, cell-mixing experiments and fluorescence resonance energy transfer (FRET) studies showed that juxtacrine signaling typically occurred in trans at the cell surface, at points of cell-cell contact. Our data suggest that the membrane-anchoring domain of ligands selectively controls their ability to participate in juxtacrine signaling and thus, only a subclass of EGFR ligands can act in a juxtacrine mode.

  3. Prenatal exposure to anti-tubercular drugs and postnatal effect on growth, development and cognitive ability in rats.

    PubMed

    Bharathi, K N; Natesh, T S; Ashwitha Reddy, A

    2012-04-27

    The effect of prenatal exposure to antitubercular drugs in therapeutic and double therapeutic doses on postnatal developments was studied in albino rats of Wistar strain. Seven groups with six female rats each were taken for the study and were allowed to mate with male in the ratio of (2:1). The drugs isoniazid 27 and 54mg/kg b.w. p.o., ethambutol 144 and 288mg/kg b.w. p.o., rifampin 54 and 108mg/kg b.w. p.o. were administered to each group from the day of pregnancy till parturition. Control group was administered with distilled water (1ml/kg). Litters of the respective groups were studied for litter size; body weight; physical development i.e. eye opening, pinna detachment, incisor eruption; behavioral development i.e. righting reflex, negative geotaxis, ascending wire mesh; motor development i.e. rotarod and cognitive function i.e. elevated plus maze, Hebb-William maze and step-down (passive avoidance). The results obtained indicate that the prenatal exposure to therapeutic dose of rifampin and double therapeutic dose of rifampin, isoniazid and ethambutol affect the postnatal growth, development and cognitive ability. Hence, the study suggests that potential benefit risk ratios to be considered for their use in pregnancy.

  4. Mutation of N-linked glycosylation at Asn548 in CD133 decreases its ability to promote hepatoma cell growth.

    PubMed

    Liu, Ying; Ren, Shifang; Xie, Liqi; Cui, Chunhong; Xing, Yang; Liu, Chanjuan; Cao, Benjin; Yang, Fan; Li, Yinan; Chen, Xiaoning; Wei, Yuanyan; Lu, Haojie; Jiang, Jianhai

    2015-08-21

    The membrane glycoprotein CD133 is a popular marker for cancer stem cells and contributes to cancer initiation and invasion in a number of tumor types. CD133 promotes tumorigenesis partly through an interaction between its phosphorylated Y828 residue and the PI3K regulatory subunit p85, and the interaction with β-catenin. Although CD133 glycosylation is supposed to be associated with its function, the contribution of N-glycosylation to its functions remains unclear. Here we analyzed the exact site(s) of N-glycosylation in CD133 by mass spectrometry and found that all eight potential N-glycosylation sites of CD133 could be indeed occupied by N-glycans. Loss of individual N-glycosylation sites had no effect on the level of expression or membrane localization of CD133. However, mutation at glycosylation site Asn548 significantly decreased the ability of CD133 to promote hepatoma cell growth. Furthermore, mutation of Asn548 reduced the interaction between CD133 and β-catenin and inhibited the activation of β-catenin signaling by CD133 overexpression. Our results identified the characteristics and function of CD133 glycosylation sites. These data could potentially shed light on molecular regulation of CD133 by glycosylation and enhance our understanding of the utility of glycosylated CD133 as a target for cancer therapies.

  5. Mutation of N-linked glycosylation at Asn548 in CD133 decreases its ability to promote hepatoma cell growth

    PubMed Central

    Xie, Liqi; Cui, Chunhong; Xing, Yang; Liu, Chanjuan; Cao, Benjin; Yang, Fan; Li, Yinan; Chen, Xiaoning; Wei, Yuanyan; Lu, Haojie; Jiang, Jianhai

    2015-01-01

    The membrane glycoprotein CD133 is a popular marker for cancer stem cells and contributes to cancer initiation and invasion in a number of tumor types. CD133 promotes tumorigenesis partly through an interaction between its phosphorylated Y828 residue and the PI3K regulatory subunit p85, and the interaction with β-catenin. Although CD133 glycosylation is supposed to be associated with its function, the contribution of N-glycosylation to its functions remains unclear. Here we analyzed the exact site(s) of N-glycosylation in CD133 by mass spectrometry and found that all eight potential N-glycosylation sites of CD133 could be indeed occupied by N-glycans. Loss of individual N-glycosylation sites had no effect on the level of expression or membrane localization of CD133. However, mutation at glycosylation site Asn548 significantly decreased the ability of CD133 to promote hepatoma cell growth. Furthermore, mutation of Asn548 reduced the interaction between CD133 and β-catenin and inhibited the activation of β-catenin signaling by CD133 overexpression. Our results identified the characteristics and function of CD133 glycosylation sites. These data could potentially shed light on molecular regulation of CD133 by glycosylation and enhance our understanding of the utility of glycosylated CD133 as a target for cancer therapies. PMID:26029999

  6. Predictive ability of genomic selection models for breeding value estimation on growth traits of Pacific white shrimp Litopenaeus vannamei

    NASA Astrophysics Data System (ADS)

    Wang, Quanchao; Yu, Yang; Li, Fuhua; Zhang, Xiaojun; Xiang, Jianhai

    2017-09-01

    Genomic selection (GS) can be used to accelerate genetic improvement by shortening the selection interval. The successful application of GS depends largely on the accuracy of the prediction of genomic estimated breeding value (GEBV). This study is a first attempt to understand the practicality of GS in Litopenaeus vannamei and aims to evaluate models for GS on growth traits. The performance of GS models in L. vannamei was evaluated in a population consisting of 205 individuals, which were genotyped for 6 359 single nucleotide polymorphism (SNP) markers by specific length amplified fragment sequencing (SLAF-seq) and phenotyped for body length and body weight. Three GS models (RR-BLUP, BayesA, and Bayesian LASSO) were used to obtain the GEBV, and their predictive ability was assessed by the reliability of the GEBV and the bias of the predicted phenotypes. The mean reliability of the GEBVs for body length and body weight predicted by the different models was 0.296 and 0.411, respectively. For each trait, the performances of the three models were very similar to each other with respect to predictability. The regression coefficients estimated by the three models were close to one, suggesting near to zero bias for the predictions. Therefore, when GS was applied in a L. vannamei population for the studied scenarios, all three models appeared practicable. Further analyses suggested that improved estimation of the genomic prediction could be realized by increasing the size of the training population as well as the density of SNPs.

  7. Predictive ability of genomic selection models for breeding value estimation on growth traits of Pacific white shrimp Litopenaeus vannamei

    NASA Astrophysics Data System (ADS)

    Wang, Quanchao; Yu, Yang; Li, Fuhua; Zhang, Xiaojun; Xiang, Jianhai

    2016-10-01

    Genomic selection (GS) can be used to accelerate genetic improvement by shortening the selection interval. The successful application of GS depends largely on the accuracy of the prediction of genomic estimated breeding value (GEBV). This study is a first attempt to understand the practicality of GS in Litopenaeus vannamei and aims to evaluate models for GS on growth traits. The performance of GS models in L. vannamei was evaluated in a population consisting of 205 individuals, which were genotyped for 6 359 single nucleotide polymorphism (SNP) markers by specific length amplified fragment sequencing (SLAF-seq) and phenotyped for body length and body weight. Three GS models (RR-BLUP, BayesA, and Bayesian LASSO) were used to obtain the GEBV, and their predictive ability was assessed by the reliability of the GEBV and the bias of the predicted phenotypes. The mean reliability of the GEBVs for body length and body weight predicted by the different models was 0.296 and 0.411, respectively. For each trait, the performances of the three models were very similar to each other with respect to predictability. The regression coefficients estimated by the three models were close to one, suggesting near to zero bias for the predictions. Therefore, when GS was applied in a L. vannamei population for the studied scenarios, all three models appeared practicable. Further analyses suggested that improved estimation of the genomic prediction could be realized by increasing the size of the training population as well as the density of SNPs.

  8. Amphibian Symbiotic Bacteria Do Not Show a Universal Ability To Inhibit Growth of the Global Panzootic Lineage of Batrachochytrium dendrobatidis

    PubMed Central

    Preziosi, Richard F.; Harrison, Xavier A.; Garner, Trenton W. J.

    2015-01-01

    Microbiomes associated with multicellular organisms influence the disease susceptibility of hosts. The potential exists for such bacteria to protect wildlife from infectious diseases, particularly in the case of the globally distributed and highly virulent fungal pathogen Batrachochytrium dendrobatidis of the global panzootic lineage (B. dendrobatidis GPL), responsible for mass extinctions and population declines of amphibians. B. dendrobatidis GPL exhibits wide genotypic and virulence variation, and the ability of candidate probiotics to restrict growth across B. dendrobatidis isolates has not previously been considered. Here we show that only a small proportion of candidate probiotics exhibited broad-spectrum inhibition across B. dendrobatidis GPL isolates. Moreover, some bacterial genera showed significantly greater inhibition than others, but overall, genus and species were not particularly reliable predictors of inhibitory capabilities. These findings indicate that bacterial consortia are likely to offer a more stable and effective approach to probiotics, particularly if related bacteria are selected from genera with greater antimicrobial capabilities. Together these results highlight a complex interaction between pathogens and host-associated symbiotic bacteria that will require consideration in the development of bacterial probiotics for wildlife conservation. Future efforts to construct protective microbiomes should incorporate bacteria that exhibit broad-spectrum inhibition of B. dendrobatidis GPL isolates. PMID:25819964

  9. Amphibian Symbiotic Bacteria Do Not Show a Universal Ability To Inhibit Growth of the Global Panzootic Lineage of Batrachochytrium dendrobatidis.

    PubMed

    Antwis, Rachael E; Preziosi, Richard F; Harrison, Xavier A; Garner, Trenton W J

    2015-06-01

    Microbiomes associated with multicellular organisms influence the disease susceptibility of hosts. The potential exists for such bacteria to protect wildlife from infectious diseases, particularly in the case of the globally distributed and highly virulent fungal pathogen Batrachochytrium dendrobatidis of the global panzootic lineage (B. dendrobatidis GPL), responsible for mass extinctions and population declines of amphibians. B. dendrobatidis GPL exhibits wide genotypic and virulence variation, and the ability of candidate probiotics to restrict growth across B. dendrobatidis isolates has not previously been considered. Here we show that only a small proportion of candidate probiotics exhibited broad-spectrum inhibition across B. dendrobatidis GPL isolates. Moreover, some bacterial genera showed significantly greater inhibition than others, but overall, genus and species were not particularly reliable predictors of inhibitory capabilities. These findings indicate that bacterial consortia are likely to offer a more stable and effective approach to probiotics, particularly if related bacteria are selected from genera with greater antimicrobial capabilities. Together these results highlight a complex interaction between pathogens and host-associated symbiotic bacteria that will require consideration in the development of bacterial probiotics for wildlife conservation. Future efforts to construct protective microbiomes should incorporate bacteria that exhibit broad-spectrum inhibition of B. dendrobatidis GPL isolates.

  10. Vacuolar system of ungerminated Colletotrichum graminicola conidia: convergence of autophagic and endocytic pathways.

    PubMed

    Schadeck, Ruth Janice Guse; Randi, Marco Antonio Ferreira; de Freitas Buchi, Dorly; Leite, Breno

    2003-01-28

    Vacuoles of ungerminated Colletotrichum graminicola conidia engulf cytoplasmic structures by a process analogous to microautophagy, demonstrated by using a vacuolar membrane acid phosphatase marker. Fusion of vesicles with vacuoles, without deposition of the acid phosphatase reaction product has been observed, suggesting other pathways of material delivery to vacuoles than microautophagy. Plasma membrane invaginations, multivesicular bodies and retention of neutral red into small vesicles, which were internalized by the vacuole, were verified. These results provided evidence for endocytosis and an active endosomal system. Together, our findings with C. graminicola demonstrated that vacuoles are very dynamic compartments, playing roles in autophagy and endocytic processes.

  11. Methods for reducing particle concentrations of Aspergillus fumigatus conidia and mouldy hay dust.

    PubMed

    Edwards, J H; Trotman, D M; Mason, O F

    1985-08-01

    The effectiveness of commercially available domestic air purifiers to reduce airborne Aspergillus fumigatus conidia and mouldy hay dust was investigated. It was found that the rate of particle clearance is a function of the volume of air passing through the purifiers but that the low throughflow of air makes their use of little value in clearing particles from a normal sized room. Vacuum cleaners were more effective than air purifiers because of their higher air throughput, so too were high volume fan systems in conjunction with simple filtration units. Ionizers had no effect but steam condensation was very efficient at clearing airborne particles.

  12. Environmental Factors Affecting Production, Release, and Field Populations of Conidia of Alternaria alternata, the Cause of Brown Spot of Citrus.

    PubMed

    Timmer, L W; Solel, Z; Gottwald, T R; Ibañez, A M; Zitko, S E

    1998-11-01

    ABSTRACT Alternaria brown spot, caused by Alternaria alternata pv. citri, affects many tangerines and their hybrids, causing loss of immature leaves and fruit and reducing the marketability of the remaining fruit. Conidial production of A. alternata was greatest on mature leaves moistened and maintained at near 100% relative humidity (RH) for 24 h, whereas leaves that had been soaked or maintained at moderate RH produced few conidia. Conidial release from filter paper cultures and infected leaves was studied in a computer-controlled environmental chamber. Release of large numbers of conidia was triggered from both substrates by sudden drops in RH or by simulated rainfall events. Vibration induced release of low numbers of conidia, but red/infrared irradiation had no effect. In field studies from 1994 to 1996, air sampling with a 7-day recording volumetric spore trap indicated that conidia were present throughout the year with periodic large peaks. The number of conidia captured was not closely related to rainfall amounts or average wind speed, but was weakly related to the duration of leaf wetness. Likewise, disease severity on trap plants placed in the field weekly during 1995 to 1996 was not closely related to conidial numbers or rainfall amounts, but was weakly related to leaf wetness duration. Sufficient inoculum appears to be available to allow infection to occur throughout the year whenever susceptible host tissue and moisture are available.

  13. The importance of head growth patterns in predicting the cognitive abilities and literacy skills of small-for-gestational-age children.

    PubMed

    Frisk, Virginia; Amsel, Rhonda; Whyte, Hilary E A

    2002-01-01

    This study evaluated the effects of head growth compromise beginning in utero and continuing, in some cases, through the first 9 months of life on the cognitive and literacy skills of school-age small-for-gestational-age (SGA) children. Seventy-one SGA children, aged 7 to 9 years (gestational ages, 24-41 weeks) and 16 full-term appropriate-for-gestational-age control children of comparable socioeconomic backgrounds and age at testing completed tests assessing intelligence, receptive language, working memory, problem solving, visual-motor integration, phonological awareness, reading, and spelling. SGA children were subdivided into head-growth pattern groups based on their head circumference at birth and at 9 months postterm. Analyses showed that SGA children with poor prenatal and postnatal head growth had the worst outcomes, followed by those with prenatal brain compromise, but good postnatal head growth. SGA children with preserved head growth in utero as well as good head growth after birth demonstrated the best outcomes, although spelling skills were deficient relative to full-term peers. The Verbal and Full Scale IQ ratings of the SGA children who had experienced brain compromise in utero declined significantly from 5 to 8 years of age. We conclude that mild intrauterine growth retardation (IUGR) has a minimal effect on the development of cognitive or academic abilities, providing that brain growth in utero is not affected. IUGR that slows brain growth in utero impairs the acquisition of some cognitive and academic abilities, even when followed by good catch-up head growth after birth, whereas poor brain growth in utero followed by little or no catch-up head growth results in widespread impairments. Findings highlight the limits to brain plasticity and emphasize the importance of optimal prenatal and postnatal brain growth.

  14. Evidence of a Differential Effect of Ability Grouping on the Reading Achievement Growth of Language-Minority Hispanics

    ERIC Educational Resources Information Center

    Robinson, Joseph P.

    2008-01-01

    Ability grouping is sometimes thought to exacerbate inequality by increasing achievement gaps; however, ability grouping may in fact benefit a fast growing and often marginalized student population: children from non-English-speaking home environments. The level-appropriate, small-group instruction received in reading ability groups may be…

  15. EST analysis of cDNA libraries from the entomopathogenic fungus Beauveria (Cordyceps) bassiana. I. Evidence for stage-specific gene expression in aerial conidia, in vitro blastospores and submerged conidia.

    PubMed

    Cho, Eun-Min; Liu, Li; Farmerie, William; Keyhani, Nemat O

    2006-09-01

    The entomopathogenic fungus Beauveria (Cordyceps) bassiana holds much promise as a pest biological control agent. B. bassiana produces at least three in vitro single cell infectious propagules, including aerial conidia, vegetative cells termed blastospores and submerged conidia, that display different morphological, biochemical and virulence properties. Populations of aerial conidia, blastospores and submerged conidia were produced on agar plates, rich liquid broth cultures and under conditions of nutrient limitation in submerged cultures, respectively. cDNA libraries were generated from mRNA isolated from each B. bassiana cell type and approximately 2,500 5' end sequences were determined from each library. Sequences derived from aerial conidia clustered into 284 contigs and 963 singlets, with those derived from blastospores and submerged conidia forming 327 contigs with 788 singlets, and 303 contigs and 1,079 contigs, respectively. Almost half (40-45 %) of the sequences in each library displayed either no significant similarity (e value >10(-4)) or similarity to hypothetical proteins found in the NCBI database. The expressed sequence tag dataset also included sequences representing a significant portion of proteins in cellular metabolism, information storage and processing, transport and cell processes, including cell division and posttranslational modifications. Transcripts encoding a diverse array of pathogenicity-related genes, including proteases, lipases, esterases, phosphatases and enzymes producing toxic secondary metabolites, were also identified. Comparative analysis between the libraries identified 2,416 unique sequences, of which 20-30 % were unique to each library, and only approximately 6 % of the sequences were shared between all three libraries. The unique and divergent representation of the B. bassiana transcriptome in the cDNA libraries from each cell type suggests robust differential gene expression profiles in response to environmental

  16. A Non-canonical Melanin Biosynthesis Pathway Protects Aspergillus terreus Conidia from Environmental Stress.

    PubMed

    Geib, Elena; Gressler, Markus; Viediernikova, Iuliia; Hillmann, Falk; Jacobsen, Ilse D; Nietzsche, Sandor; Hertweck, Christian; Brock, Matthias

    2016-05-19

    Melanins are ubiquitous pigments found in all kingdoms of life. Most organisms use them for protection from environmental stress, although some fungi employ melanins as virulence determinants. The human pathogenic fungus Aspergillus fumigatus and related Ascomycetes produce dihydroxynaphthalene- (DHN) melanin in their spores, the conidia, and use it to inhibit phagolysosome acidification. However, biosynthetic origin of melanin in a related fungus, Aspergillus terreus, has remained a mystery because A. terreus lacks genes for synthesis of DHN-melanin. Here we identify genes coding for an unusual NRPS-like enzyme (MelA) and a tyrosinase (TyrP) that A. terreus expressed under conidiation conditions. We demonstrate that MelA produces aspulvinone E, which is activated for polymerization by TyrP. Functional studies reveal that this new pigment, Asp-melanin, confers resistance against UV light and hampers phagocytosis by soil amoeba. Unexpectedly, Asp-melanin does not inhibit acidification of phagolysosomes, thus likely contributing specifically to survival of A. terreus conidia in acidic environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Comparison between gene expression of conidia and germinating phase in Trichophyton rubrum.

    PubMed

    Yang, Li; Wang, LingLing; Peng, JunPing; Yu, Lu; Liu, Tao; Leng, WenChuan; Yang, Jian; Chen, LiHong; Zhang, WenLiang; Zhang, Qian; Qi, YiPeng; Jin, Qi

    2007-06-01

    Trichophyton rubrum is a dominating superficial dermatophyte, whose conidial germination is correlated to pathopoiesis and a highly important developmental process. To investigate the changes of physiology, biochemistry and cytology during the germination, we selected 3364 function identified ESTs from T. rubrum cDNA library to construct cDNA microarrays, and compared the gene expression levels of conidia and germinating phase. Data analysis indicated that 335 genes were up-regulated during the germination, which mainly encoded translated, modified proteins and structural proteins. The constituents of cell wall and cell membrane were synthetized abundantly, suggesting that they are the foundation of cell morphogenesis. The ingredients of the two-component signal transduction system were up-regulated, presuming that they were important for the conidial germination. Genes of various metabolic pathways were expressed prosperously, especially the genes that participated in glycolysis and oxidative phosphorylation were up-regulated on the whole, demonstrating that in the environment with sufficient oxygen and glucose, conidia obtained energy through aerobic respiration. This paper provides important clues which are helpful to understanding the changes in gene expression, signal conduction and metabolism characteristics during T. rubrum conidial germination, and possess significant meaning to the study of other superficial dermatophytes.

  18. Conidia of the insect pathogenic fungus, Metarhizium anisopliae, fail to adhere to mosquito larval cuticle

    PubMed Central

    Greenfield, Bethany P. J.; Lord, Alex M.; Dudley, Ed; Butt, Tariq M.

    2014-01-01

    Adhesion of conidia of the insect pathogenic fungus, Metarhizium anisopliae, to the arthropod host cuticle initially involves hydrophobic forces followed by consolidation facilitated by the action of extracellular enzymes and secretion of mucilage. Gene expression analysis and atomic force microscopy were used to directly quantify recognition and adhesion between single conidia of M. anisopliae and the cuticle of the aquatic larval stage of Aedes aegypti and a representative terrestrial host, Tenebrio molitor. Gene expression data indicated recognition by the pathogen of both hosts; however, the forces for adhesion to the mosquito were approximately five times lower than those observed for Tenebrio. Although weak forces were recorded in response to Aedes, Metarhizium was unable to consolidate firm attachment. An analysis of the cuticular composition revealed an absence of long-chain hydrocarbons in Aedes larvae which are thought to be required for fungal development on host cuticle. This study provides, to our knowledge, the first evidence that Metarhizium does not form firm attachment to Ae. aegypti larvae in situ, therefore preventing the normal route of invasion and pathogenesis from occuring. PMID:26064542

  19. Growth, fecundity and competitive ability of transgenic Trifolium subterraneum subsp. subterraneum cv. Leura expressing a sunflower seed albumin gene.

    PubMed

    Godfree, Robert C; Woods, Matthew J; Young, Andrew G; Burdon, Jeremy J; Higgins, T J V

    2004-01-01

    Ecological risk assessment is an important step in the production and commercialisation of transgenic plants. To date, however, most risk assessment studies have been performed on crop plants, and few have considered the ecological consequences associated with genetic modification of pasture species. In this study we compared the growth, yield, population dynamics and competitive ability of transgenic Trifolium subterraneum subsp. subterraneum cv. Leura (subclover) expressing a nutritive sunflower seed albumin (ssa) gene with the equivalent non-transgenic commercial line in a glasshouse competition trial. Plants were grown in low-fertility soil typical of unimproved native southeastern Australian grasslands. We measured survivorship, seed production rate, seed germination rate, seed weight, dry weight yield and the intrinsic rate of population increase (lambda) of plants grown in mixtures and monocultures over a range of densities (250 to 2000 plants m(-2)), and also determined intragenotypic and intergenotypic competition coefficients for each line. There were no significant differences between transgenic and non-transgenic plants in any of the measured variables except survivorship; transgenic plants had a significantly lower survival rate than non-transgenic plants when grown at high densities (p<0.01). However, density-dependent effects were observed for all measured variables, and in all models plant density affected the response variables more than the presence of the transgene. Based on these results, we conclude that the ssa gene construct appears to confer no advantage to transgenic T. s. subterraneum cv. Leura growing in mixed or pure swards under the fertility and density regimes examined in the trial. Our data also suggest that transgenic subterranean clover expressing the ssa gene is unlikely to exhibit a competitive advantage over associated non-transgenic commercial cultivars when grown in dense swards in low-fertility pastures.

  20. Effects of Single-Drop Impactions and Natural and Simulated Rains on the Dispersal of Botryosphaeria dothidea Conidia.

    PubMed

    Ahimera, Neph; Gisler, Simon; Morgan, David P; Michailides, Themis J

    2004-11-01

    ABSTRACT Laboratory and field experiments were conducted to study the dispersal of Botryosphaeria dothidea conidia using single-drop impactions and natural and simulated precipitations. For laboratory studies, 200 single drops were released from a height of 1 m on infected pistachio nuts. On pieces of photographic film, 50% of the droplets were collected within 20 mm (average droplet travel distance) of the target area, and the droplets ranged from 0.041 to 3.19 mm in diameter, with an average of 0.3 mm. Each droplet carried an average of 23 B. dothidea conidia. In 3 years of field experiments, rainwater was collected in funnels connected to bottles positioned at different heights inside the tree canopy and at different distances away from the edge of tree canopy in three commercial pistachio orchards in San Joaquin, Yolo, and Glenn counties in California. Numbers of conidia in rainwater varied among and within sampling seasons by sampling dates and orchards. Up to 67,000 conidia/ml were obtained in rainwater samples collected from an orchard in Yolo County. Rainwater from orchards in Yolo and Glenn counties contained a consistently higher number of conidia than rainwater collected from the orchard in San Joaquin County. Variation in numbers of conidia also existed among heights where bottles were located. There were significantly more conidia in rainwater collected inside than outside tree canopies. Inside tree canopies, bottles located at 100 and 150 cm above ground collected more B. dothidea conidia than those placed at 50 and 200 cm. Conidia were collected as far as 1 m from the tree canopy edge. Based on data from the Glenn County orchard, a linear relationship between number of conidia (Y) and rainfall amount (X) in millimeters was determined as Y = 240X - 3,867, with r(2) = 0.91, which meant that a minimum of 16.1 mm of rain was needed to disperse conidia of B. dothidea. The power law model best described the dispersal gradients of B. dothidea propagules in

  1. Effects of Airflow and Changing Humidity on the Aerosolization of Respirable Fungal Fragments and Conidia of Botrytis cinerea

    PubMed Central

    2012-01-01

    The purpose of this study was to investigate the aerosolization of particles (micro- and macroconidia and fragments) from Botrytis cinerea cultures in relation to potential human inhalation in indoor environments. The influence of the following factors on the aerosolization of B. cinerea particles was studied: exposure to airflow, relative humidity (rh), changing rh, and plant or building materials. The aerodynamic diameter (da) and the respirable fraction of the aerosolized particles were determined. Conidia and fragments of B. cinerea were not aerosolized as a response to a decrease in the rh. In contrast, both micro- and macroconidia and fungal fragments were aerosolized when exposed to an airflow of 1.5 m s−1 or 0.5 m s−1. Significantly more particles of microconidial size and fragment size were aerosolized at a low rh (18 to 40% rh) than at a higher rh (60 to 80% rh) when cultures were exposed to airflow. The size of the respirable fraction of the aerosolized particles was dependent on the rh but not on the growth material. At high rh, about 30% of the aerosolized particles were of respirable size, while at low rh, about 70% were of respirable size. During low rh, more fungal (1→3)-β-d-glucan and chitinase were aerosolized than during high rh. In conclusion, exposure to external physical forces such as airflow is necessary for the aerosolization of particles from B. cinerea. The amount and size distribution are highly affected by the rh, and more particles of respirable sizes were aerosolized at low rh than at high rh. PMID:22447608

  2. Toxicity of ozone gas to conidia of Penicillium digitatum, P. italicum, and Botrytis cinerea and control of gray mold on table grapes

    USDA-ARS?s Scientific Manuscript database

    Penicillium digitatum, P. italicum, and Botrytis cinerea attack fresh fruit and cause significant postharvest decay losses and the toxicity of ozone (O3) gas at different relative humidities to control their conidia was determined. Conidia were exposed to an atmosphere containing 200 to 350 µL L-1 o...

  3. Defense Infrastructure: Communities Need Additional Guidance and Information to Improve Their Ability to Adjust to DOD Installation Closure or Growth

    DTIC Science & Technology

    2013-05-01

    strategies communities have used in dealing with base closures and growth since 2005 and economic and population data in those communities and (2...from 2006 through 2011. Since 2005, 23 other installations have experienced population increases that have resulted in net growth of about 191,000...Including Dependents and Nonmission-Related Contractors) at 23 Growth Installations from Fiscal Years 2006 through 2012 18 Table 3: Population Change in

  4. A Quantitative Dynamic Simulation of Bremia lactucae Airborne Conidia Concentration above a Lettuce Canopy.

    PubMed

    Fall, Mamadou Lamine; Van der Heyden, Hervé; Carisse, Odile

    2016-01-01

    Lettuce downy mildew, caused by the oomycete Bremia lactucae Regel, is a major threat to lettuce production worldwide. Lettuce downy mildew is a polycyclic disease driven by airborne spores. A weather-based dynamic simulation model for B. lactucae airborne spores was developed to simulate the aerobiological characteristics of the pathogen. The model was built using the STELLA platform by following the system dynamics methodology. The model was developed using published equations describing disease subprocesses (e.g., sporulation) and assembled knowledge of the interactions among pathogen, host, and weather. The model was evaluated with four years of independent data by comparing model simulations with observations of hourly and daily airborne spore concentrations. The results show an accurate simulation of the trend and shape of B. lactucae temporal dynamics of airborne spore concentration. The model simulated hourly and daily peaks in airborne spore concentrations. More than 95% of the simulation runs, the daily-simulated airborne conidia concentration was 0 when airborne conidia were not observed. Also, the relationship between the simulated and the observed airborne spores was linear. In more than 94% of the simulation runs, the proportion of the linear variation in the hourly-observed values explained by the variation in the hourly-simulated values was greater than 0.7 in all years except one. Most of the errors came from the deviation from the 1:1 line, and the proportion of errors due to the model bias was low. This model is the only dynamic model developed to mimic the dynamics of airborne inoculum and represents an initial step towards improved lettuce downy mildew understanding, forecasting and management.

  5. A Quantitative Dynamic Simulation of Bremia lactucae Airborne Conidia Concentration above a Lettuce Canopy

    PubMed Central

    Fall, Mamadou Lamine; Van der Heyden, Hervé; Carisse, Odile

    2016-01-01

    Lettuce downy mildew, caused by the oomycete Bremia lactucae Regel, is a major threat to lettuce production worldwide. Lettuce downy mildew is a polycyclic disease driven by airborne spores. A weather-based dynamic simulation model for B. lactucae airborne spores was developed to simulate the aerobiological characteristics of the pathogen. The model was built using the STELLA platform by following the system dynamics methodology. The model was developed using published equations describing disease subprocesses (e.g., sporulation) and assembled knowledge of the interactions among pathogen, host, and weather. The model was evaluated with four years of independent data by comparing model simulations with observations of hourly and daily airborne spore concentrations. The results show an accurate simulation of the trend and shape of B. lactucae temporal dynamics of airborne spore concentration. The model simulated hourly and daily peaks in airborne spore concentrations. More than 95% of the simulation runs, the daily-simulated airborne conidia concentration was 0 when airborne conidia were not observed. Also, the relationship between the simulated and the observed airborne spores was linear. In more than 94% of the simulation runs, the proportion of the linear variation in the hourly-observed values explained by the variation in the hourly-simulated values was greater than 0.7 in all years except one. Most of the errors came from the deviation from the 1:1 line, and the proportion of errors due to the model bias was low. This model is the only dynamic model developed to mimic the dynamics of airborne inoculum and represents an initial step towards improved lettuce downy mildew understanding, forecasting and management. PMID:26953691

  6. [Compatibility of two fungal biocontrol agents conidia with commercial chemical acaricides].

    PubMed

    Jiang, Yu; Feng, Mingguang

    2006-07-01

    In this paper, the biological compatibility of fungal biocontrol agents Beauveria bassiana and Paecilomyces fumosoroseus conidia with 10 commercial chemical acaricides were assayed, based on the conidial germination rates in nutritional liquid and on SDAY plate. The results showed that nutritional liquid was more available than SDAY plate in the assay. So far as the 24 h conidial viability concerned, there were significant differences among the test acaricides with the concentrations of recommended for field spray and 5 and 10 fold dilutions, as well as between the two fungal agents. Since acaricides azocyclotin, liuyangmycin, dicofol and avermectin had strong inhibitory effects on the 24 h germination rate of both fungal agents conidia, their combined application with fungal agents was unsuitable for mite control. However, the combined application of pyridaben, propargite, chlorpyrifos, hexythiazox or amitraz with either B. bassiana or P. fumosoroseus was practical, because of their short-term compatibility. When the mixtures of oil-based B. bassiana formulation with the three concentrations of pyridaben, propargite and chlorpyrifos were stored at 4 degrees C or at ambient temperature for 12 months, none of the three chemicals was considered to be good enough for a combined formulation due to the great variability in long-term compatibility. Nevertheless, chlorpyrifos exhibited an encouraging long-term compatibility with B. bassiana, because its low concentration in the fungal formulation did not affect the conidial viability during a 6.5-month period of storage at ambient temperature. When stored at 4 degrees C in dark, the B. bassiana formulation containing low or medium concentration of chlorpyrifos retained the conidial viability of > 90% for up to 12 months.

  7. Effects of a Cover Crop on Splash Dispersal of Colletotrichum acutatum Conidia.

    PubMed

    Ntahimpera, N; Ellis, M A; Wilson, L L; Madden, L V

    1998-06-01

    ABSTRACT A rain simulator, with generated rains of 11 and 30 mm/h, was used to determine the effect of a cover crop or intercrop on the splash dispersal of Colletotrichum acutatum conidia. Dispersal through sudangrass, which can be used as a 'living mulch', was tested at two planting densities (140 or 280 kg/ha) and two heights (5 and 20 cm) and compared with a control consisting of a bare soil. Dispersal of C. acutatum conidia was assessed by counting colonies formed from spore-bearing splash droplets deposited in sheltered petri plates containing a selective medium. Both a cover crop and rain intensity significantly affected splash dispersal as measured by the interpolated total number of colonies (denoted by Sigma) from 0 to 72 cm from the inoculum source and in a time span of 61 min of generated rain (P < 0.001). However, there was no significant interaction of cover crop and intensity (P > 0.90). Dispersal with a 30-mm/h rain was higher than dispersal with a 11-mm/h rain, and presence of a cover crop significantly reduced dispersal compared with bare soil (P < 0.001). Of the treatments with sudangrass, cover crop planting density did not affect dispersal overall, but there was greater spore dispersal with the taller sudangrass at the higher planting density, due in part to the higher rate of water splashing with the tall grass compared with the short grass. Spore deposition in the petri plates could be functionally related to distance and time using a diffusion-type model, and parameter estimates could be used to explain the effects of cover crop on Sigma. Although the relationship between cover crop properties and splash dispersal is complex, results show the potential beneficial effects of the cover crop on disease management.

  8. Thermal inactivation of Botrytis cinerea conidia in synthetic medium and strawberry puree.

    PubMed

    Villa-Rojas, R; Sosa-Morales, M E; López-Malo, A; Tang, J

    2012-04-16

    Botrytis cinerea is one of the most important post-harvest molds that cause quality deterioration of strawberries and other fruits even during refrigeration storage. This research studied the effects of thermal inactivation of B. cinerea in synthetic medium and strawberry puree using hot water baths at different temperatures. These media were studied in order to determine if results obtained in a solution with the major components of the fruit (synthetic media), are comparable to the ones obtained in fruit purees. The results demonstrated that B. cinerea spores can be inactivated by heat treatments using relatively low temperatures (42-46 °C). Inactivation curves were well described by first order kinetics (R² 0.91-0.99). B. cinerea conidia inoculated in synthetic medium required less time to achieve one log reduction in population than those inoculated in the fruit puree. D values were 22, 8.5, 4 and 1.4 min at 42, 44, 46 and 48 °C, respectively, in synthetic medium; while D values in strawberry puree were 44.9, 13.8, 4.7 and 1.4 min at 42, 44, 46 and 48 °C, respectively. The z values obtained were 4.15 and 5.08 °C for the strawberry puree and synthetic medium respectively, showing higher sensitivity of B. cinerea in fruit purees than in the synthetic medium. Thus, a change in the medium composition had a marked difference in the heat inactivation of B. cinerea conidia, and the results obtained in synthetic medium are not accurate to describe the behavior of the microorganism in the fruit.

  9. Effects of whole-stream nutrient enrichment on the concentration and abundance of aquatic hyphomycete conidia in transport

    Treesearch

    Vol. 96(1): 57-65 Mycologia

    2004-01-01

    The concentrations and relative abundances of aquatic hyphomycete conidia in water were followed during a three-year study in two headwater streams at Coweeta Hydrologic Laboratory, North Carolina, using the membrane-filtration technique. After a one-ye& pretreatment period, one of the streams was enriched continuously with inorganic nutrients (N+P) for two years...

  10. Importance of complement 3 and mannose receptors in phagocytosis of Paracoccidioides brasiliensis conidia by Nramp1 congenic macrophages lines.

    PubMed

    Jiménez, María del P; Restrepo, Angela; Radzioch, Danuta; Cano, Luz E; García, Luis F

    2006-06-01

    Genetic factors influence susceptibility to Paracoccidioidomycosis, a Latin American endemic mycosis. The pattern of susceptibility of congenic mouse strains infected with Paracoccidioides brasiliensis resembles the pattern of the Nramp1 gene. Thus, congenic murine bone-marrow-derived macrophage lines B10R (Nramp1rGly169) and B10S (null Nramp1 protein expression, Nramp1sAsp169) were infected with P. brasiliensis conidia and compared, under opsonic and nonopsonic conditions. Opsonization increased the percentage of phagocytosis by both cell lines. B10R macrophages exhibited a higher percentage of cells with associated conidia and higher number of conidia per macrophage than B10S. Heat-inactivation and EDTA treatment of serum used for opsonization, and treatment of macrophages with anti-complement receptor 3 (CR3) decreased phagocytosis by both cell lines. alpha-methyl-d-mannoside reduced phagocytosis by B10R macrophages, suggesting that the mannose receptor participates in phagocytosis by these cells. The CR3 expression was similar on both cell lines and B10R expressed more mannose receptors, but neither cell line expressed CR1. IFNgamma decreased the conversion of conidia to the yeast form of P. brasiliensis in B10R, but not in B10S macrophages.

  11. Arthrornyces and Blastosporella, two new genera of conidia-producing lyophylloid agarics (Agaricales, Basidiornycota) from the neotropics

    Treesearch

    Timothy J. Baroni; Ana Esperanza Franco-molano; D. Jean Lodge; Daniel L. Lindner; Egon Horak; Valerie Hofstetter

    2007-01-01

    Two new genera encompassing three new species of lyophylloid agarics that produce conidia on the basidiomata are described. Arthromyces is a genus comprised of two very different arthrospore-producing mushroom species found in the Greater Antilles and Central America. Blastosporella is a monotypic genus with spherical balls of...

  12. Arthromyces and Blastosporella, two new genera of conidia-producing lyophylloid agarics (Agaricales, Basidiomycota) from the neotropics

    Treesearch

    Timothy J. Baroni; Ana Esperanza Franco-Molano; D. Jean Lodge; Daniel L. Lindner; Egon Horak; Valerie Hofstetter

    2007-01-01

    Two new genera encompassing three new species of lyophylloid agarics that produce conidia on the basidiomata are described. Arthromyces is a genus comprised of two very different arthrospore-producing mushroom species found in the Greater Antilles and Central America. Blastosporella is a monotypic genus with spherical balls of blastospores covering the pileus surface...

  13. QUANTIFICATION OF STACHYBOTRYS CHARTARUM CONIDIA IN INDOOR DUST USING REAL TIME, FLUORESCENT PROBE-BASED DETECTION OF PCR PRODUCTS

    EPA Science Inventory

    Analyses of fungal spores or conidia in indoor dust samples can be useful for determining the contamination status of building interiors and in signaling instances where potentially harmful exposures of building occupants to these organisms may exist. A recently developed method ...

  14. A proteomic approach to identifying proteins differentially expressed in conidia and mycelium of the entomopathogenic fungus Metarhizium acridum.

    PubMed

    Barros, Bruno H R; da Silva, Sérgio H; dos ReisMarques, Everaldo Dos Reis; Rosa, José C; Yatsuda, Ana Patrícia; Roberts, Donald W; Braga, Gilberto U L

    2010-07-01

    Metarhizium spp. is an important worldwide group of entomopathogenic fungi used as an interesting alternative to chemical insecticides in programs of agricultural pest and disease vector control. Metarhizium conidia are important in fungal propagation and also are responsible for host infection. Despite their importance, several aspects of conidial biology, including their proteome, are still unknown. We have established conidial and mycelial proteome reference maps for Metarhizium acridum using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF MS). In all, 1130±102 and 1200±97 protein spots were detected in ungerminated conidia and fast-growing mycelia, respectively. Comparison of the two protein-expression profiles reveled that only 35% of the protein spots were common to both developmental stages. Out of 94 2-DE protein spots (65 from conidia, 25 from mycelia and two common to both) analyzed using mass spectrometry, seven proteins from conidia, 15 from mycelia and one common to both stages were identified. The identified protein spots exclusive to conidia contained sequences similar to known fungal stress-protector proteins (such as heat shock proteins (HSP) and 6-phosphogluconate dehydrogenase) plus the fungal allergen Alt a 7, actin and the enzyme cobalamin-independent methionine synthase. The identified protein spots exclusive to mycelia included proteins involved in several cell housekeeping biological processes. Three proteins (HSP 90, 6-phosphogluconate dehydrogenase and allergen Alt a 7) were present in spots in conidial and mycelial gels, but they differed in their locations on the two gels.

  15. General mental ability and two types of adaptation to unforeseen change: applying discontinuous growth models to the task-change paradigm.

    PubMed

    Lang, Jonas W B; Bliese, Paul D

    2009-03-01

    The present research provides new insights into the relationship between general mental ability (GMA) and adaptive performance by applying a discontinuous growth modeling framework to a study of unforeseen change on a complex decision-making task. The proposed framework provides a way to distinguish 2 types of adaptation (transition adaptation and reacquisition adaptation) from 2 common performance components (skill acquisition and basal task performance). Transition adaptation refers to an immediate loss of performance following a change, whereas reacquisition adaptation refers to the ability to relearn a changed task over time. Analyses revealed that GMA was negatively related to transition adaptation and found no evidence for a relationship between GMA and reacquisition adaptation. The results are integrated within the context of adaptability research, and implications of using the described discontinuous growth modeling framework to study adaptability are discussed.

  16. Investigating the impacts of field-realistic exposure to a neonicotinoid pesticide on bumblebee foraging, homing ability and colony growth.

    PubMed

    Stanley, Dara A; Russell, Avery L; Morrison, Sarah J; Rogers, Catherine; Raine, Nigel E

    2016-10-01

    The ability to forage and return home is essential to the success of bees as both foragers and pollinators. Pesticide exposure may cause behavioural changes that interfere with these processes, with consequences for colony persistence and delivery of pollination services.We investigated the impact of chronic exposure (5-43 days) to field-realistic levels of a neonicotinoid insecticide (2·4 ppb thiamethoxam) on foraging ability, homing success and colony size using radio frequency identification (RFID) technology in free-flying bumblebee colonies.Individual foragers from pesticide-exposed colonies carried out longer foraging bouts than untreated controls (68 vs. 55 min). Pesticide-exposed bees also brought back pollen less frequently than controls indicating reduced foraging performance.A higher proportion of bees from pesticide-exposed colonies returned when released 1 km from their nests; this is potentially related to increased orientation experience during longer foraging bouts. We measured no impact of pesticide exposure on homing ability for bees released from 2 km, or when data were analysed overall.Despite a trend for control colonies to produce more new workers earlier, we found no overall impacts of pesticide exposure on whole colony size. Synthesis and applications. This study shows that field-realistic neonicotinoid exposure can have impacts on both foraging ability and homing success of bumblebees, with implications for the success of bumblebee colonies in agricultural landscapes and their ability to deliver crucial pollination services. Pesticide risk assessments should include bee species other than honeybees and assess a range of behaviours to elucidate the impact of sublethal effects. This has relevance for reviews of neonicotinoid risk assessment and usage policy world-wide.

  17. Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus.

    PubMed

    Xie, Shiwei; Zhou, Weiwen; Tian, Lixia; Niu, Jin; Liu, Yongjian

    2016-08-01

    An 8-week feeding trial was conducted to evaluate the effect of N-acetyl cysteine (NAC) and glycine supplementation on growth performance, glutathione (GSH) synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus. Four practical diets were formulated, control, control +0.2% NAC, control +0.5% glycine, control +0.2% NAC +0.5% glycine. Each diet was randomly assigned to quadruplicate groups of 30 fish (approximately 9.5 g). The weight gain and specific growth rate were significantly increased with the supplementation of NAC and glycine. While they had no effect on feed efficiency feed intake and survival. Glutathion peroxidase (GPx) was increased by NAC and γ-glutamine cysteine synthase (γ-GCS) in plasma were increased by glycine. After the feeding trail, fish were challenged by Streptococcus iniae, fish fed the diet supplemented with NAC obtained significantly higher survival rate after 72 h challenge test. NAC also decreased malonaldehyde (MDA) in liver, increased glutathione S-transferase (GST) activity in plasma, up-regulated mRNA expression of Superoxide dismutase (SOD) and GPx in liver and headkidney. Dietary supplementation of glycine increased the anti-oxidative ability of tilapia through increase anti-oxidative enzyme activity (SOD, glutathione reductase, myeloperoxidase) and up-regulate anti-oxidative gene expression (SOD). Immune ability only enhanced by the supplementation of NAC through increased interleukin-1β (IL-1β) mRNA expression. These results clearly indicated that the supplementation of NAC and glycine can significantly improve the growth performance of tilapia, and NAC also enhance the anti-oxidative and immune capacity of tilapia, glycine could only enhance the anti-oxidative ability.

  18. "Elastic" property of mesoporous silica shell: for dynamic surface enhanced Raman scattering ability monitoring of growing noble metal nanostructures via a simplified spatially confined growth method.

    PubMed

    Lin, Min; Wang, Yunqing; Sun, Xiuyan; Wang, Wenhai; Chen, Lingxin

    2015-04-15

    The Raman enhancing ability of noble metal nanoparticles (NPs) is an important factor for surface enhanced Raman scattering (SERS) substrate screening, which is generally evaluated by simply mixing as-prepared NPs with Raman reporters for Raman signal measurements. This method usually leads to incredible results because of the NP surface coverage nonuniformity and reporter-induced NP aggregation. Moreover, it cannot realize in situ, continuous SERS characterization. Herein, we proposed a dynamic SERS monitoring strategy for NPs with precisely tuned structures based on a simplified spatially confined NP growth method. Gold nanorod (AuNR) seed NPs were coated with a mesoporous silica (mSiO2) shell. The permeability of mSiO2 for both reactive species and Raman reporters rendered the silver overcoating reaction and SERS indication of NP growth. Additionally, the mSiO2 coating ensured monodisperse NP growth in a Raman reporter-rich reaction system. Moreover, "elastic" features of mSiO2 were observed for the first time, which is crucial for holding the growing NP without breakage. This feature makes the mSiO2 coating adhere to metal NPs throughout the growing process, providing a stable Raman reporter distribution microenvironment near the NPs and ensuring that the substrate's SERS ability comparison is accurate. Three types of NPs, i.e., core-shell Au@AgNR@mSiO2, Au@AuNR@mSiO2, and yolk-shell Au@void@AuNR@mSiO2 NPs, were synthesized via core-shell overgrowth and galvanic replacement methods, showing the versatility of the approach. The living cell SERS labeling ability of Au@AgNR@mSiO2-based tags was also demonstrated. This strategy addresses the problems of multiple batch NP preparation, aggregation, and surface adsorption differentiation, which is a breakthrough for the dynamic comparison of SERS ability of metal NPs with precisely tuned structures and optical properties.

  19. A novel approach of utilization of the fungal conidia biomass to remove heavy metals from the aqueous solution through immobilization

    NASA Astrophysics Data System (ADS)

    Cai, Chun-Xiang; Xu, Jian; Deng, Nian-Fang; Dong, Xue-Wei; Tang, Hao; Liang, Yu; Fan, Xian-Wei; Li, You-Zhi

    2016-11-01

    The biomass of filamentous fungi is an important cost-effective biomass for heavy metal biosorption. However, use of free fungal cells can cause difficulties in the separation of biomass from the effluent. In this study, we immobilized the living conidia of the heavy metal-resistant Penicillium janthinillum strain GXCR by polyvinyl alcohol (PVA)-sodium alginate (SA) beads to remove heavy metals from an aqueous solution containing a low concentration (70 mg/L) of Cu, Pb, and Cd. The PVA-SA-conidia beads showed perfect characters of appropriate mechanical strength suitable for metal removal from the dynamic wastewater environment, an ideal settleability, easy separation from the solution, and a high metal biosorption and removal rate even after four cycles of successive sorption-desorption of the beads, overcoming disadvantages when fungal biomasses alone are used for heavy metal removal from wastewater. We also discuss the major biosorption-affecting factors, biosorption models, and biosorption mechanisms.

  20. A novel approach of utilization of the fungal conidia biomass to remove heavy metals from the aqueous solution through immobilization.

    PubMed

    Cai, Chun-Xiang; Xu, Jian; Deng, Nian-Fang; Dong, Xue-Wei; Tang, Hao; Liang, Yu; Fan, Xian-Wei; Li, You-Zhi

    2016-11-16

    The biomass of filamentous fungi is an important cost-effective biomass for heavy metal biosorption. However, use of free fungal cells can cause difficulties in the separation of biomass from the effluent. In this study, we immobilized the living conidia of the heavy metal-resistant Penicillium janthinillum strain GXCR by polyvinyl alcohol (PVA)-sodium alginate (SA) beads to remove heavy metals from an aqueous solution containing a low concentration (70 mg/L) of Cu, Pb, and Cd. The PVA-SA-conidia beads showed perfect characters of appropriate mechanical strength suitable for metal removal from the dynamic wastewater environment, an ideal settleability, easy separation from the solution, and a high metal biosorption and removal rate even after four cycles of successive sorption-desorption of the beads, overcoming disadvantages when fungal biomasses alone are used for heavy metal removal from wastewater. We also discuss the major biosorption-affecting factors, biosorption models, and biosorption mechanisms.

  1. A novel approach of utilization of the fungal conidia biomass to remove heavy metals from the aqueous solution through immobilization

    PubMed Central

    Cai, Chun-Xiang; Xu, Jian; Deng, Nian-Fang; Dong, Xue-Wei; Tang, Hao; Liang, Yu; Fan, Xian-Wei; Li, You-Zhi

    2016-01-01

    The biomass of filamentous fungi is an important cost-effective biomass for heavy metal biosorption. However, use of free fungal cells can cause difficulties in the separation of biomass from the effluent. In this study, we immobilized the living conidia of the heavy metal-resistant Penicillium janthinillum strain GXCR by polyvinyl alcohol (PVA)-sodium alginate (SA) beads to remove heavy metals from an aqueous solution containing a low concentration (70 mg/L) of Cu, Pb, and Cd. The PVA-SA-conidia beads showed perfect characters of appropriate mechanical strength suitable for metal removal from the dynamic wastewater environment, an ideal settleability, easy separation from the solution, and a high metal biosorption and removal rate even after four cycles of successive sorption-desorption of the beads, overcoming disadvantages when fungal biomasses alone are used for heavy metal removal from wastewater. We also discuss the major biosorption-affecting factors, biosorption models, and biosorption mechanisms. PMID:27848987

  2. Localization of melanin in conidia of Alternaria alternata using phage display antibodies.

    PubMed

    Carzaniga, Raffaella; Fiocco, Daniela; Bowyer, Paul; O'Connell, Richard J

    2002-03-01

    Melanins derived from 1,8-dihydroxynaphthalene (DHN) are important for the pathogenicity and survival of fungi causing disease in both plants and animals. However, precise information on their location within fungal cell walls is lacking. To obtain antibodies for the immunocytochemical localization of melanin, 83 phage antibodies binding to 1,8-DHN were selected from a naive semisynthetic single-chain Fv (scFv) phage display library. Sequence analysis of the heavy chain binding domains of 17 antibodies showed a high frequency of positively charged amino acids. One antibody, designated M1, was characterized in detail. M1 bound specifically to 1,8-DHN in competitive inhibition enzyme-linked immunosorbent assays, showing no cross-reaction with nine structurally related phenolic compounds. Epitope recognition required two hydroxyl groups in a 1,8 configuration. M1 also bound to naturally occurring melanin isolated from mycelia of Alternaria alternata, suggesting that epitopes remain accessible in polymerized melanin. Transmission electron microscopy-immunogold labeling, using M1 in the form of soluble scFv fragments, showed that melanin was located in the septa and outer (primary) walls of wild-type A. alternata conidia, but not those of an albino mutant, AKT88-1. The M1 antibody provides a new tool for detecting melanized pathogens in plant and animal tissues and for precisely mapping the distribution of the polymer within spores, appressoria, and hyphae.

  3. IL-1 signaling inhibits Trichophyton rubrum conidia development and modulates the IL-17 response in vivo.

    PubMed

    Yoshikawa, Fábio Seiti Yamada; Ferreira, Lucas Gonçalves; de Almeida, Sandro Rogério

    2015-01-01

    Dermatophytosis are one of the most common fungal infections in the world. They compromise keratinized tissues and the main etiological agent is Trichophyton rubrum. Macrophages are key cells in innate immunity and prominent sources of IL-1β, a potent inflammatory cytokine whose main production pathway is by the activation of inflammasomes and caspase-1. However, the role of inflammasomes and IL-1 signaling against T.rubrum has not been reported. In this work, we observed that bone marrow-derived macrophages produce IL-1β in response to T.rubrum conidia in a NLRP3-, ASC- and caspase-1-dependent fashion. Curiously, lack of IL-1 signaling promoted hyphae development, uncovering a protective role for IL-1β in macrophages. In addition, mice lacking IL-1R showed reduced IL-17 production, a key cytokine in the antifungal defense, in response to T.rubrum. Our findings point to a prominent role of IL-1 signaling in the immune response to T.rubrum, opening the venue for the study of this pathway in other fungal infections.

  4. Conidial germination in Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans: influence of growth conditions and antifungal susceptibility profiles

    PubMed Central

    de Mello, Thaís Pereira; Aor, Ana Carolina; de Oliveira, Simone Santiago Carvalho; Branquinha, Marta Helena; dos Santos, André Luis Souza

    2016-01-01

    In the present study, we have investigated some growth conditions capable of inducing the conidial germination in Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans. Germination in Sabouraud medium (pH 7.0, 37ºC, 5% CO2) showed to be a typically time-dependent event, reaching ~75% in S. minutisporum and > 90% in S. apiospermum, S. aurantiacum and L. prolificans after 4 h. Similar germination rate was observed when conidia were incubated under different media and pHs. Contrarily, temperature and CO2 tension modulated the germination. The isotropic conidial growth (swelling) and germ tube-like projection were evidenced by microscopy and cytometry. Morphometric parameters augmented in a time-dependent fashion, evidencing changes in size and granularity of fungal cells compared with dormant 0 h conidia. In parallel, a clear increase in the mitochondrial activity was measured during the transformation of conidia-into-germinated conidia. Susceptibility profiles to itraconazole, fluconazole, voriconazole, amphotericin B and caspofungin varied regarding each morphotype and each fungal species. Overall, the minimal inhibitory concentrations for hyphae were higher than conidia and germinated conidia, except for caspofungin. Collectively, our study add new data about the conidia-into-hyphae transformation in Scedosporium and Lomentospora species, which is a relevant biological process of these molds directly connected to their antifungal resistance and pathogenicity mechanisms. PMID:27355215

  5. Nitric Oxide Participation in the Fungicidal Mechanism of Gamma Interferon-Activated Murine Macrophages against Paracoccidioides brasiliensis Conidia

    PubMed Central

    Gonzalez, Angel; de Gregori, Waldemar; Velez, Diana; Restrepo, Angela; Cano, Luz E.

    2000-01-01

    Paracoccidioidomycosis, a systemic mycosis restricted to Latin America and produced by the dimorphic fungus Paracoccidioides brasiliensis, is probably acquired by inhalation of conidia produced by the mycelial form. The macrophage (Mφ) represents the major cell defense against this pathogen; when activated with gamma interferon (IFN-γ), murine Mφs kill the fungus by an oxygen-independent mechanism. Our goal was to determine the role of nitric oxide in the fungicidal effect of Mφs on P. brasiliensis conidia. The results revealed that IFN-γ-activated murine Mφs inhibited the conidium-to-yeast transformation process in a dose-dependent manner; maximal inhibition was observed in Mφs activated with 50 U/ml and incubated for 96 h at 37°C. When Mφs were activated with 150 to 200 U of cytokine per ml, the number of CFU was 70% lower than in nonactivated controls, indicating that there was a fungicidal effect. The inhibitory effect was reversed by the addition of anti-IFN-γ monoclonal antibodies. Activation by IFN-γ also enhanced Mφ nitric oxide production, as revealed by increasing NO2 values (8 ± 3 μM in nonactivated Mφs versus 43 ± 13 μM in activated Mφs). The neutralization of IFN-γ also reversed nitric oxide production at basal levels (8 ± 5 μM). Additionally, we found that there was a significant inverse correlation (r = −0.8975) between NO2− concentration and transformation of P. brasiliensis conidia. Additionally, treatment with any of the three different nitric oxide inhibitors used (arginase, NG-monomethyl-l-arginine, and aminoguanidine), reverted the inhibition of the transformation process with 40 to 70% of intracellular yeast and significantly reduced nitric oxide production. These results show that IFN-γ-activated murine Mφs kill P. brasiliensis conidia through the l-arginine–nitric oxide pathway. PMID:10768942

  6. Arthromyces and Blastosporella, two new genera of conidia-producing lyophylloid agarics (Agaricales, Basidiomycota) from the neotropics.

    PubMed

    Baroni, Timothy J; Franco-Molano, Ana Esperanza; Lodge, D Jean; Lindner, Daniel L; Horak, Egon; Hofstetter, Valerie

    2007-05-01

    Two new genera encompassing three new species of lyophylloid agarics that produce conidia on the basidiomata are described. Arthromyces is a genus comprised of two very different arthrospore-producing mushroom species found in the Greater Antilles and Central America. Blastosporella is a monotypic genus with spherical balls of blastospores covering the pileus surface with age and is known from Hispaniola and Colombia. A key to the species of Arthromyces is included.

  7. A fullerene colloidal suspension stimulates the growth and denitrification ability of wastewater treatment sludge-derived bacteria.

    PubMed

    Huang, Fei; Ge, Ling; Zhang, Bo; Wang, Yun; Tian, Hao; Zhao, Liping; He, Yiliang; Zhang, Xiaojun

    2014-08-01

    Fullerene (C60) is a nanoparticle that has been widely studied and applied in numerous commodities. However, there are concerns regarding its potential negative impact on the environment. A fullerene colloidal suspension (nC60) is known for its property of selectively inhibiting the growth of microorganisms. In this study, using denaturing gradient gel electrophoresis fingerprinting technology, we found that fullerene altered the structure of a sludge-derived microbial community. Specifically, the bacteria from Bacillus, Acidovorax and Cloacibacterium genera were enriched in abundance when supplemented with nC60 at pH 6.5 under aerobic conditions. The effects of the fullerene colloidal suspension on a strain of Bacillus isolated from the same microbial community were evaluated to further characterize the growth-stimulating effect of nC60. The biomass of cultures of this strain incubated with nC60 concentrations ranging from 3 mg L(-1) to 7 mg L(-1) was approximately twice that of the control during the stationary phase. The fullerene also induced higher superoxide dismutase activity in Bacillus cereus. Furthermore, the nitrate removal rate of B. cereus increased to nearly 55% in the presence of 5 mg L(-1) nC60, compared to 35% for the control. Meanwhile, the cumulative loading amount of nitrite was reduced from 33 μg mL(-1) to 25 μg mL(-1) by the addition of 5 mg L(-1) nC60. Our results demonstrate that the fullerene colloidal suspension is conditionally capable of promoting the growth and denitrification metabolism of certain bacteria, such as B. cereus. Fullerene might have both inhibitory and stimulatory effects on microorganisms in various environments.

  8. A proteomic and genetic analysis of the Neurospora crassa conidia cell wall proteins identifies two glycosyl hydrolases involved in cell wall remodeling

    PubMed Central

    Ao, Jie; Aldabbous, Mash’el; Notaro, Marysa J.; Lojacono, Mark; Free, Stephen J.

    2016-01-01

    A proteomic analysis of the conidial cell wall identified 35 cell wall proteins. A comparison with the proteome of the vegetative hyphae showed that 16 cell wall proteins were shared, and that these shared cell wall proteins were cell wall biosynthetic proteins or cell wall structural proteins. Deletion mutants for 34 of the genes were analyzed for phenotypes indicative of conidial cell wall defects. Mutants for two cell wall glycosyl hydrolases, the CGL-1 β-1,3-glucanase (NCU07523) and the NAG-1 exochitinase (NCU10852), were found to have a conidial separation phenotype. These two enzymes function in remodeling the cell wall between adjacent conidia to facilitate conidia formation and dissemination. Using promoter::RFP and promoter::GFP constructs, we demonstrated that the promoters for 15 of the conidia-specific cell wall genes, including cgl-1 and nag-1, provided for conidia-specific gene expression or for a significant increase in their expression during conidiation. PMID:27381444

  9. Surface structure characterization of Aspergillus fumigatus conidia mutated in the melanin synthesis pathway and their human cellular immune response.

    PubMed

    Bayry, Jagadeesh; Beaussart, Audrey; Dufrêne, Yves F; Sharma, Meenu; Bansal, Kushagra; Kniemeyer, Olaf; Aimanianda, Vishukumar; Brakhage, Axel A; Kaveri, Srini V; Kwon-Chung, Kyung J; Latgé, Jean-Paul; Beauvais, Anne

    2014-08-01

    In Aspergillus fumigatus, the conidial surface contains dihydroxynaphthalene (DHN)-melanin. Six-clustered gene products have been identified that mediate sequential catalysis of DHN-melanin biosynthesis. Melanin thus produced is known to be a virulence factor, protecting the fungus from the host defense mechanisms. In the present study, individual deletion of the genes involved in the initial three steps of melanin biosynthesis resulted in an altered conidial surface with masked surface rodlet layer, leaky cell wall allowing the deposition of proteins on the cell surface and exposing the otherwise-masked cell wall polysaccharides at the surface. Melanin as such was immunologically inert; however, deletion mutant conidia with modified surfaces could activate human dendritic cells and the subsequent cytokine production in contrast to the wild-type conidia. Cell surface defects were rectified in the conidia mutated in downstream melanin biosynthetic pathway, and maximum immune inertness was observed upon synthesis of vermelone onward. These observations suggest that although melanin as such is an immunologically inert material, it confers virulence by facilitating proper formation of the A. fumigatus conidial surface.

  10. Modulation of conidia production and expression of the gene bbrgs1 from Beauveria bassiana by oxygen pulses and light.

    PubMed

    Rodriguez-Gomez, Divanery; Marcial-Quino, Jaime; Loera, Octavio

    2015-09-01

    Light and oxidant states affect the conidiation in diverse fungi, although the response has not been described when both stimuli are applied simultaneously. Conidial production and quality in Beauveria bassiana were analysed under four conditions for a wild-type (wt) strain and a previously isolated mutant (mt): normal atmosphere (21% O2; NA) or oxygen-enriched pulses (26% O2; OEP), with either light (L) or darkness (D). The response was complemented by following the expression of the bbrgs1 gene, encoding a regulator of the G-protein signal associated to conidia production. Conidiation was not significantly affected in the mutant strain by any condition (highest value with NA-L: 2.7×10(8)concm(-2)). Relative to maximal levels under NA (NA-D: 4×10(7)concm(2)), the wt strain diminished conidiation by 34-fold under OEP. The expression of bbrgs1 was higher (up to 188 times) in the mutant strain in every condition relative to the wt strain, in fact expression levels were consistent with the conidiation yields between strains. Viability and hydrophobicity were less affected by culture conditions, although pathogenicity parameters improved in conidia from OEP. The response to OEP, either with light or darkness, was strain-dependent for conidial production, viability, hydrophobicity and infectivity of conidia, then these parameters could be modulated in mass production processes. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Surface Structure Characterization of Aspergillus fumigatus Conidia Mutated in the Melanin Synthesis Pathway and Their Human Cellular Immune Response

    PubMed Central

    Bayry, Jagadeesh; Beaussart, Audrey; Dufrêne, Yves F.; Sharma, Meenu; Bansal, Kushagra; Kniemeyer, Olaf; Aimanianda, Vishukumar; Brakhage, Axel A.; Kaveri, Srini V.; Kwon-Chung, Kyung J.

    2014-01-01

    In Aspergillus fumigatus, the conidial surface contains dihydroxynaphthalene (DHN)-melanin. Six-clustered gene products have been identified that mediate sequential catalysis of DHN-melanin biosynthesis. Melanin thus produced is known to be a virulence factor, protecting the fungus from the host defense mechanisms. In the present study, individual deletion of the genes involved in the initial three steps of melanin biosynthesis resulted in an altered conidial surface with masked surface rodlet layer, leaky cell wall allowing the deposition of proteins on the cell surface and exposing the otherwise-masked cell wall polysaccharides at the surface. Melanin as such was immunologically inert; however, deletion mutant conidia with modified surfaces could activate human dendritic cells and the subsequent cytokine production in contrast to the wild-type conidia. Cell surface defects were rectified in the conidia mutated in downstream melanin biosynthetic pathway, and maximum immune inertness was observed upon synthesis of vermelone onward. These observations suggest that although melanin as such is an immunologically inert material, it confers virulence by facilitating proper formation of the A. fumigatus conidial surface. PMID:24818666

  12. Effects of carbon dioxide on growth of proteolytic Clostridium botulinum, its ability to produce neurotoxin, and its transcriptome.

    PubMed

    Artin, Ingrid; Mason, David R; Pin, Carmen; Schelin, Jenny; Peck, Michael W; Holst, Elisabet; Rådström, Peter; Carter, Andrew T

    2010-02-01

    The antimicrobial gas carbon dioxide is frequently used in modified atmosphere packaging. In the present study, the effects of CO2 (10 to 70%, vol/vol) on gene expression (measured using quantitative reverse transcription-PCR and a whole-genome DNA microarray) and neurotoxin formation (measured using an enzyme-linked immunosorbent assay [ELISA]) by proteolytic Clostridium botulinum type A1 strain ATCC 3502 were studied during the growth cycle. Interestingly, in marked contrast to the situation with nonproteolytic C. botulinum types B and E, CO2 had little effect on any of these parameters. At all CO2 concentrations, relative expression of neurotoxin cluster genes peaked in the transition between exponential and stationary phases, with evidence of a second rise in expression in late stationary phase. Microarray analysis enabled identification of coding sequences whose expression profiles matched those of the neurotoxin cluster. Further research is needed to determine whether these are connected to neurotoxin formation or are merely growth phase associated.

  13. The effects of dietary soybean isoflavones on growth, innate immune responses, hepatic antioxidant abilities and disease resistance of juvenile golden pompano Trachinotus ovatus.

    PubMed

    Zhou, Chuanpeng; Lin, Heizhao; Ge, Xianping; Niu, Jin; Wang, Jun; Wang, Yun; Chen, Lixiong; Huang, Zhong; Yu, Wei; Tan, Xiaohong

    2015-03-01

    The present study was conducted to investigate the effects of dietary soybean isoflavones (SI) supplementation on growth performance, innate immune responses, hepatic antioxidant abilities, heat shock protein 70 (HSP70) gene expression and resistance to the pathogen Vibrio harveyi in Trachinotus ovatus. A basal diet was supplemented with SI at 0, 10, 20, 40, 60, 80 mg kg(-1) feed for 8 weeks. Significantly maximum weight gain (WG) and specific growth rate (SGR) were observed in treatment with 40 mg kg(-1) SI supplement (P < 0.05). Feed conversion ratio (FCR), feeding rate (FR) and survival rate were not significantly different among treatments. Fish fed a diet with 40 mg kg(-1) SI showed significant increase in plasma total protein content, complement 3 content, lysozyme activity as well as respiratory burst activity, but decrease in alanine aminotransferase and aspartate aminotransferase activities (P < 0.05). Increased plasma alkaline phosphatase activity, hepatic total antioxidative capacity, catalase activity and superoxide dismutase activity were also noticed in fish fed SI at 40 or 60 mg kg(-1) (P < 0.05). On the contrary, the lowest hepatic malondialdehyde (MDA) content was observed in fish fed SI at 40 mg kg(-1) (P < 0.05). Compared with the control, the relative level of HSP70 mRNA in fish fed SI at 40-80 mg kg(-1) were significantly increased, respectively (P < 0.05). After challenge with V. harveyi, significant higher post-challenge survival was observed in fish fed diets with 40-80 mg kg(-1) SI supplement than that in control group (P < 0.05). These results indicated that dietary intake containing SI could enhance the immune ability of fish and improve its resistance to infection by V. harveyi. Especially supplementation with 40 mg kg(-1) SI to the fish for 8 weeks showed remarkable improvement in the growth, non-specific immune responses, hepatic antioxidant abilities and HSP70 gene expression.

  14. Emergence Time and Skin Melanin Spot Patterns Do Not Correlate with Growth Performance, Social Competitive Ability or Stress Response in Farmed Rainbow Trout.

    PubMed

    Gesto, Manuel; Skov, Peter V; Jokumsen, Alfred

    2017-01-01

    In wild salmonid fish, specific individual behavioral traits have been correlated with the timing of fry emergence from their gravel spawning nests; Early emerging fish display more aggressive behavior and have a higher probability of becoming socially dominant, compared to fish that emerge at a later stage. Apart from aggression and dominance, other behavioral and metabolic traits, such as boldness, metabolic rate, or growth, have also been linked to emergence time. Altogether, the traits of early- and late-emerging fish resemble those of the proactive and reactive stress-coping style, respectively. As proactive fish are considered more resilient to stress, it may be desirable to select these for aquaculture production. However, it is currently unclear to what extent the link between emergence time and stress-coping styles is maintained in the selective breeding of farmed fish. In the present study, eyed eggs from a commercial supplier were hatched, and larvae fractionated according to their emergence time. Later on, juvenile fish from different emergence fractions were subjected to a stress challenge and also tested to evaluate their competitive ability for food. Beyond some slight dissimilarities in the acute stress responses, emergence fraction displayed no correlation with growth rates, or the ability to compete for feed. Within the whole group of fish utilized in the experiments, no relationship between skin melanin spot pattern and growth performance, stress response intensity, or competitive ability was found. Altogether, the differences in physiological traits related to emergence time were not as strong as those found in earlier studies. It is hypothesized, that the origin and degree of domestication of the fish might be partly responsible for this. The predictive value of skin spots or emergence time to infer the fish stress coping style in farmed fish is also discussed.

  15. Effects of Palygorskite Inclusion on the Growth Performance, Meat Quality, Antioxidant Ability, and Mineral Element Content of Broilers.

    PubMed

    Cheng, Y F; Chen, Y P; Li, X H; Yang, W L; Wen, C; Zhou, Y M

    2016-09-01

    The present study was conducted to investigate different levels of palygorskite supplementation on the growth performance, meat quality, muscular oxidative status, and mineral element accumulation of broilers. One hundred ninety-two 1-day-old Arbor Acres broiler chicks were allocated to four dietary treatments with six replicates of eight chicks per replicate. Birds in the four treatments were given a basal diet supplemented with 0, 5, 10 and 20 g/kg palygorskite for 42 days, respectively. Compared with the control group, neither 5 g/kg nor 10 g/kg palygorskite inclusion affected growth performance of broilers during the 42-day study (P > 0.05). However, the highest level of palygorskite supplementation at 20 g/kg increased feed/gain ratio (F/G) of broilers (P < 0.001). Yellowness (P < 0.001) and redness (P = 0.003) of breast muscle and yellowness of leg muscle (P = 0.001) were decreased by palygorskite supplementation at the levels of 10 g/kg and especially 20 g/kg. In addition, redness of leg muscle was also reduced by the inclusion of 20 g/kg palygorskite (P = 0.009). In contrast, malonaldehyde (MDA) accumulation in the breast muscle was significantly increased by 20 g/kg palygorskite supplementation (P < 0.001). Supplementation of palygorskite at either 10 or 20 g/kg significantly decreased lead (Pb) accumulation in the breast (P = 0.001) or thigh (P = 0.045) and copper (Cu) accumulation in the breast (P = 0.022). In conclusion, growth performance, meat color, and antioxidant capacity of meat would reduce with the increasing level of palygorskite supplementation, whereas a higher level of palygorskite (10 or 20 g/kg) can alter mineral element accumulations in muscles as evidenced by reduced muscular Cu and Pb contents.

  16. MoTea4-Mediated Polarized Growth Is Essential for Proper Asexual Development and Pathogenesis in Magnaporthe oryzae▿†

    PubMed Central

    Patkar, Rajesh N.; Suresh, Angayarkanni; Naqvi, Naweed I.

    2010-01-01

    Polarized growth is essential for cellular development and function and requires coordinated organization of the cytoskeletal elements. Tea4, an important polarity determinant, regulates localized F-actin assembly and bipolar growth in fission yeast and directional mycelial growth in Aspergillus. Here, we characterize Tea4 in the rice blast fungus Magnaporthe oryzae (MoTea4). Similar to its orthologs, MoTea4-green fluorescent protein (MoTea4-GFP) showed punctate distribution confined to growth zones, particularly in the mycelial tips, aerial hyphae, conidiophores, conidia, and infection structures (appressoria) in Magnaporthe. MoTea4 was dispensable for vegetative growth in Magnaporthe. However, loss of MoTea4 led to a zigzag morphology in the aerial hyphae and a huge reduction in conidiation. The majority of the tea4Δ conidia were two celled, as opposed to the tricellular conidia in the wild type. Structure-function analysis indicated that the SH3 and coiled-coil domains of MoTea4 are necessary for proper conidiation in Magnaporthe. The tea4Δ conidia failed to produce proper appressoria and consequently failed to infect the host plants. The tea4Δ conidia and germ tubes showed disorganized F-actin structures with significantly reduced numbers of cortical actin patches. Compared to the wild-type conidia, the tea4Δ conidia showed aberrant germination, poor cytoplasmic streaming, and persistent accumulation of lipid droplets, likely due to the impaired F-actin cytoskeleton. Latrunculin A treatment of germinating wild-type conidia showed that an intact F-actin cytoskeleton is indeed essential for appressorial development in Magnaporthe. We show that MoTea4 plays an important role in organizing the F-actin cytoskeleton and is essentially required for polarized growth and morphogenesis during asexual and pathogenic development in Magnaporthe. PMID:20472691

  17. The Phytoplankton Nannochloropsis oculata Enhances the Ability of Roseobacter Clade Bacteria to Inhibit the Growth of Fish Pathogen Vibrio anguillarum

    PubMed Central

    Sharifah, Emilia Noor; Eguchi, Mitsuru

    2011-01-01

    Background Phytoplankton cultures are widely used in aquaculture for a variety of applications, especially as feed for fish larvae. Phytoplankton cultures are usually grown in outdoor tanks using natural seawater and contain probiotic or potentially pathogenic bacteria. Some Roseobacter clade isolates suppress growth of the fish pathogen Vibrio anguillarum. However, most published information concerns interactions between probiotic and pathogenic bacteria, and little information is available regarding the importance of phytoplankton in these interactions. The objectives of this study, therefore, were to identify probiotic Roseobacter clade members in phytoplankton cultures used for rearing fish larvae and to investigate their inhibitory activity towards bacterial fish pathogens in the presence of the phytoplankton Nannochloropsis oculata. Methodology/Principal Findings The fish pathogen V. anguillarum, was challenged with 6 Roseobacter clade isolates (Sulfitobacter sp. (2 strains), Thalassobius sp., Stappia sp., Rhodobacter sp., and Antarctobacter sp.) from phytoplankton cultures under 3 different nutritional conditions. In an organic nutrient-rich medium (VNSS), 6 Roseobacter clade isolates, as well as V. anguillarum, grew well (109 CFU/ml), even when cocultured. In contrast, in a phytoplankton culture medium (ESM) based on artificial seawater, coculture with the 6 isolates decreased the viability of V. anguillarum by approximately more than 10-fold. Excreted substances in media conditioned by growth of the phytoplankton N. oculata (NCF medium) resulted in the complete eradication of V. anguillarum when cocultured with the roseobacters. Autoclaved NCF had the same inhibitory effect. Furthermore, Sulfitobacter sp. much more efficiently incorporated 14C- photosynthetic metabolites (14C-EPM) excreted by N. oculata than did V. anguillarum. Conclusion/Significance Cocultures of a phytoplankton species and Roseobacter clade members exhibited a greater antibacterial

  18. Aromatase gene and its effects on growth, reproductive and maternal ability traits in a multibreed sheep population from Brazil

    PubMed Central

    2009-01-01

    We determined the polymorphism C242T of the aromatase gene (Cyp19) and its allelic frequency, as well as the effect of the variants on productive and reproductive traits in 71 purebred Santa Inês sheep, 13 purebred Brazilian Somali sheep, nine purebred Poll Dorset sheep, and 18 crossbred 1/2 Dorper sheep. The animals were genotyped using the PCR-RFLP technique. The influence of the animal's genotype on its performance or on the performance of its lambs was analyzed by the least square method. Another factor assessed was the importance of the animal's genotype in analysis models for quantitative breeding value estimates, and whether there were differences among the averages of breeding values of animals with different genotypes for this gene. In the sample studied, no AA individuals were observed; the AB and BB frequencies were 0.64 and 0.36, respectively. All Brazilian Somali sheep were of genotype BB. All 1/2 Dorper BB animals presented a lower age at first lambing, and the Santa Inês BB ewes presented a lower lambing interval. In these same genetic groups, AB ewes presented higher litter weight at weaning. This is evidence that BB ewes have a better reproductive performance phenotype, whereas AB ewes present a better maternal ability phenotype. However, in general, animals with genotype AB presented better average breeding values than those with genotype BB. PMID:21637510

  19. Pleurotus ostreatus biofilm-forming ability and ultrastructure are significantly influenced by growth medium and support type.

    PubMed

    Pesciaroli, L; Petruccioli, M; Federici, F; D'Annibale, A

    2013-06-01

    To investigate the effect of support and growth medium (GM) on Pleurotus ostreatus biofilm production, specific metabolic activity (SMA) and ultrastructure. Biofilms were developed on membranes covering a broad range of surface properties and, due to the applicative implications of mixed biofilms, on standard bacterial GM in stationary and shaken culture. Hydrophilic (glass fibre, Duran glass and hydroxyapatite) and mild hydrophobic (polyurethane, stainless steel, polycarbonate, nylon) supports were more adequate for biofilm attachment than the hydrophobic Teflon. Among the GM, sucrose-asparagine (SA) was more conducive to biofilm production than Luria-Bertani and M9. GM was more influential than support type on biofilm ultrastructure, and a high compactness was evident in biofilms developed on SA. Biofilms on Duran glass were more efficient than planktonic cultures in olive-mill wastewater treatment. The main effects of support and GM variables and their binary interactions on both biofilm production and SMA were all highly significant (P < 0·001): thus, the magnitude of the effect of each variable strongly depended on the level of the other one. There is a lack of basic information regarding physiology and ultrastructure of P. ostreatus biofilms. To our knowledge, this is the first attempt to fill this gap, thus representing a basis for future studies. © 2013 The Society for Applied Microbiology.

  20. Insulin-like growth factor-1 endues monocytes with immune suppressive ability to inhibit inflammation in the intestine

    PubMed Central

    Ge, Rong-Ti; Mo, Li-Hua; Wu, Ruijin; Liu, Jiang-Qi; Zhang, Huan-Ping; Liu, Zhigang; Liu, Zhanju; Yang, Ping-Chang

    2015-01-01

    The pathogenesis of some chronic inflammation such as inflammatory bowel disease is unclear. Insulin-like growth factor-1 (IGF1) has active immune regulatory capability. This study aims to investigate into the mechanism by which IGF1 modulates the monocyte (Mo) properties to inhibit immune inflammation in the intestine. In this study, the production of IGF1 by intestinal epithelial cells was evaluated by real time RT-PCR and Western blotting. Mos were analyzed by flow cytometry. A mouse colitis model was created with trinitrobenzene sulfonic acid. The results showed that mouse IECs produced IGF1, which could be up regulated by exposure to CpG-ODN (CpG-oligodeoxynueleotides) in the culture. Culture the CpG-ODN-primed IEC cells and Mos or exposure of Mos to IGF1 in the culture induced the Mos to express IL-10. The IGF1-primed Mos showed the immune suppressive effect on inhibiting the immune inflammation in the mouse colon. In conclusion, the IGF1-primed Mos are capable of suppressing immune inflammation in the intestine. PMID:25588622

  1. Spices Mycobiota and Mycotoxins Available in Saudi Arabia and Their Abilities to Inhibit Growth of Some Toxigenic Fungi

    PubMed Central

    2007-01-01

    The prevalence and population density of the mycobiota of 50 samples belonging to 10 kinds of spices (anise, black pepper, red pepper, black cumin, peppermint, cardamom, clove, cumin, ginger and marjoram) which collected from different places in Jeddah Governorate were studied. The natural occurrence of mycotoxins in those samples was also investigated. Fifteen genera and thirty - one species of fungi in addition to one species variety were isolated and identified during this study. The most common genera were Aspergillus, Penicillium and Fusarium. Aflatoxins (12~40 µg/kg) were detected in the extract of 5 samples of each of anise seeds and black pepper fruits; three samples of black cumin seeds and on sample only of each of peppermint and marjoram leaves out of 5 samples tested of each. Sterigmatocystin (15~20 µg/kg) was detected in some samples of red pepper, cumin and marjoram. The inhibitory effects of 10 kinds of powdered spices were tested against 3 toxigenic isolates of fungi (Aspergillus flavus, A. versicolor and Penicillium citrinum). Clove proved to be antimycotic compounds. It inhibited the growth of the tested toxigenic fungi. Black pepper, peppermint, cardamom, cumin and marjoram completely inhibited aflatoxins production, while black pepper and cardamom also completely inhibited sterigmatocystin production. PMID:24015069

  2. Spices mycobiota and mycotoxins available in saudi arabia and their abilities to inhibit growth of some toxigenic fungi.

    PubMed

    Bokhari, Fardos M

    2007-06-01

    The prevalence and population density of the mycobiota of 50 samples belonging to 10 kinds of spices (anise, black pepper, red pepper, black cumin, peppermint, cardamom, clove, cumin, ginger and marjoram) which collected from different places in Jeddah Governorate were studied. The natural occurrence of mycotoxins in those samples was also investigated. Fifteen genera and thirty - one species of fungi in addition to one species variety were isolated and identified during this study. The most common genera were Aspergillus, Penicillium and Fusarium. Aflatoxins (12~40 µg/kg) were detected in the extract of 5 samples of each of anise seeds and black pepper fruits; three samples of black cumin seeds and on sample only of each of peppermint and marjoram leaves out of 5 samples tested of each. Sterigmatocystin (15~20 µg/kg) was detected in some samples of red pepper, cumin and marjoram. The inhibitory effects of 10 kinds of powdered spices were tested against 3 toxigenic isolates of fungi (Aspergillus flavus, A. versicolor and Penicillium citrinum). Clove proved to be antimycotic compounds. It inhibited the growth of the tested toxigenic fungi. Black pepper, peppermint, cardamom, cumin and marjoram completely inhibited aflatoxins production, while black pepper and cardamom also completely inhibited sterigmatocystin production.

  3. Low pressure mode combined with OsO4 vapor fixation and sputter-coating for the preservation of delicate aerial hyphae and conidia in the ESEM.

    PubMed

    Coetzee, Stephan H; Jordaan, Anine; Mpuchane, Sisai F

    2005-08-01

    The newer generation of environmental scanning electron microscopes (ESEMs) allows samples to be viewed under a range of different vacuum conditions. No specific sample preparation protocols are required with the ESEMs, as fresh, unfixed samples are used and discarded later. We have worked out a method that preserves aerial hyphae on biltong that closely resemble fresh specimens and may be stored for viewing at a later date. Another advantage is that fixed samples are more resilient to the variable vacuum encountered in the ESEM. When biltong samples with fungal growth were first studied, we observed that vacuum-related artifacts were induced unless vacuum conditions and changes in pressure were carefully controlled. Damage readily occured in conidia and its delicate hyphae. Fresh, unfixed samples are very vulnerable to these artifacts. In addition, biltong proved to be a problematic study sample because of its high salt content, its hygroscopic nature as well as being laden with spices. To eliminate these artifacts, the preservation of specimens by OsO4 vapor fixation combined with a special sputter-coating technique is described. Previous studies confirmed that OsO4 vapor fixation is superior to traditional immersion fixation methods for the examination of hyphae and conidia of various fungi in a conventional SEM. However, both preparation methods induce sample shrinkage. We observed that OsO4 vapor fixation followed by Au coating under strictly controlled vacuum conditions induced fewer artifacts and gave the best images with minimum distortion in low pressure (LP) mode. The proposed method allows samples to be viewed both in ESEM and LP mode. There are however some disadvantages inherent to ESEM mode. Even when viewing fixed, coated samples, care should be taken to maintain a pressure of not lower than 0.2 Torr in the specimen chamber. It is critical that different samples have the same vacuum exposure history, as shrinkage and collapse were found to be

  4. Intact Cell/Spore Mass Spectrometry of Fusarium Macro Conidia for Fast Isolate and Species Differentiation

    NASA Astrophysics Data System (ADS)

    Dong, Hongjuan; Marchetti-Deschmann, Martina; Winkler, Wolfgang; Lohninger, Hans; Allmaier, Guenter

    The focus of this paper is the development of an approach called intact cell mass spectrometry (ICMS) or intact spore mass spectrometry (ISMS) based on the technique matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for the rapid differentiation and identification of Fusarium species. Several parameters, which are known to affect the quality of IC mass spectra, have been investigated in detail by varying the MALDI matrix as well as the solvent system, in which the matrix has been dissolved, the solvent system for sample purification and the type of sample/MALDI matrix deposition technique. In the end characteristic as well as highly reproducible IC or IS mass spectra or peptide/protein fingerprints of three Fusarium species (F. cerealis, F. graminearum and F. poae) including 16 Fusarium isolates derived from different hosts and geographical locations have been obtained. Unscaled hierarchical cluster analysis based on ICMS data of eight selected Fusarium isolates of two species F. graminearum and F. poae revealed significant difference among the peptide/protein pattern of them. The results of the applied cluster analysis proved that, ICMS is a powerful approach for the rapid differentiation of Fusarium species. In addition, an on-target tryptic digestion was applied to Fusarium macro conidia spores to identify proteins using MALDI post source decay (PSD) fragment ion analysis. Two kinds of trypsin, namely bead-immobilized - to favor cleavage of surface-associated proteins - and non-immobilized trypsin were applied and compared. The results showed that the latter is more suitable for generating sequence tags by PSD fragment ion analysis.

  5. [Variation in the viability and the metabolism of internally reserved nutrients of Beauveria bassiana conidia during storage at different regimes of water content and temperature].

    PubMed

    Feng, Mingguang; Ying, Shenghua

    2002-04-01

    While the fresh powder (with water content of 58.9 +/- 1.6%) and vacuum-freeze dried (VFD) one (with water content of 7.4 +/- 0.9%) of Beauveria bassiana SGBB8702 conidia were stored at 4 degrees C and 20 degrees C, their viability and contents of internally reserved saccharides and proteins were examined at 5 days intervals. It was found during one-month storage that the water content and temperature interactively affected the levels of conidia viability and the contents of the reserved saccharides and proteins, which in turn correlated considerably well to the viability. Stored at 4 degrees C and 20 degrees C, the VFD conidia lost content of saccharides by 13.4% and 14.1%, content of proteins by 39.2% and 38.2%, and viability by 32.0% and 55.8% when germinating in water only and 6.7% and 10.4% when germinating in 2% glucose solution plus 0.5% peptone, respectively. In contrast, the four estimates of the fresh conidia stored at 4 degrees C and 20 degrees C decreased by 42.4% and 43.2%, 66.3% and 65.4%, 96.4% and 99.4%, and 9.9% and 98.4%, respectively. Thus, water content of B. bassiana conidia affected variation ranges of the viability and the internally reserved nutrients whereas storage temperature influenced their variation rates. However, depletion of the internally reserved nutrients did not necessarily inactivate the conidia. Instead, such conidia may germinate at relatively high level during a period of time as long as being supplied with sufficient nutrients. In another experiment, the powder of VFD conidia with water content being reduced to 4.0 +/- 0.9% were half-monthly examined for viability during one-year storage. The viability only decreased slightly from 99.0% to 90.2% at 4 degrees C by the end of one year. Stored at 20 degrees C, the viability also declined slowly during the first 165 days but dramatically decreased afterwards with little being detected on day 240. A modeling analysis showed that the time for the VFD conidia to lose 50% viability

  6. Evaluation of strains isolated by growth on naphthalene and biphenyl for hybridization of genes to dioxygenase probes and polychlorinated biphenyl-degrading ability.

    PubMed

    Pellizari, V H; Bezborodnikov, S; Quensen, J F; Tiedje, J M

    1996-06-01

    Approximately equal numbers of bacteria were isolated from primarily tropical soils by growth on biphenyl and naphthalene to compare their competence in polychlorinated biphenyl (PCB) degradation. The strains isolated by growth on biphenyl catalyzed more extensive PCB degradation than the strains isolated by growth on naphthalene, suggesting that naphthalene cocontamination may be only partially effective in stimulating the cometabolism of lower chlorinated PCBs. Probes were made from the bph, nah, and tod genes encoding the large iron iron sulfur protein of the dioxygenase complex and hybridized to 19 different strains. The hybridization patterns did not correlate well with the substrates of isolation, suggesting that there is considerable diversity in these genes in nature and that probe hybridization is not a reliable indication of catabolic capacity. The strains with the most extensive PCB degradation capacity did strongly hybridize to the bph probe, but a few strains that exhibited strong hybridization had poor PCB-degrading ability. Of the 19 strains studied, 5 hybridized to more than one probe and 2, including one strong PCB degrader, hybridized to all three probes. Southern blots showed that the bph and nah probes hybridized to separate bands, suggesting that multiple dioxygenases were present. Multiple dioxygenases may be an important feature of competitive decomposers in nature and hence may not be rare. Most of the isolates identified were members of the beta subgroup of the Proteobacteria, a few were gram positive, and none were true Pseudomonas species.

  7. Evaluation of strains isolated by growth on naphthalene and biphenyl for hybridization of genes to dioxygenase probes and polychlorinated biphenyl-degrading ability.

    PubMed Central

    Pellizari, V H; Bezborodnikov, S; Quensen, J F; Tiedje, J M

    1996-01-01

    Approximately equal numbers of bacteria were isolated from primarily tropical soils by growth on biphenyl and naphthalene to compare their competence in polychlorinated biphenyl (PCB) degradation. The strains isolated by growth on biphenyl catalyzed more extensive PCB degradation than the strains isolated by growth on naphthalene, suggesting that naphthalene cocontamination may be only partially effective in stimulating the cometabolism of lower chlorinated PCBs. Probes were made from the bph, nah, and tod genes encoding the large iron iron sulfur protein of the dioxygenase complex and hybridized to 19 different strains. The hybridization patterns did not correlate well with the substrates of isolation, suggesting that there is considerable diversity in these genes in nature and that probe hybridization is not a reliable indication of catabolic capacity. The strains with the most extensive PCB degradation capacity did strongly hybridize to the bph probe, but a few strains that exhibited strong hybridization had poor PCB-degrading ability. Of the 19 strains studied, 5 hybridized to more than one probe and 2, including one strong PCB degrader, hybridized to all three probes. Southern blots showed that the bph and nah probes hybridized to separate bands, suggesting that multiple dioxygenases were present. Multiple dioxygenases may be an important feature of competitive decomposers in nature and hence may not be rare. Most of the isolates identified were members of the beta subgroup of the Proteobacteria, a few were gram positive, and none were true Pseudomonas species. PMID:8787402

  8. Development of a TaqMan real-time PCR assay for quantification of airborne conidia of Botrytis squamosa and management of botrytis leaf blight of onion.

    PubMed

    Carisse, O; Tremblay, D M; Lévesque, C A; Gindro, K; Ward, P; Houde, A

    2009-11-01

    The use of a DNA-based method for quantifying airborne inoculum of Botrytis squamosa, a damaging pathogen of onion, was investigated. A method for purifying DNA from conidia collected using rotating-arm samplers and quantifying it using a TaqMan real-time quantitative polymerase chain reaction (qPCR) assay is described. The sensitivity of the qPCR assay was high, with a detection limit of 2 conidia/rod. A linear relationship between numbers of conidia counted with a compound microscope and those determined with the qPCR assay was obtained. Receiver operating characteristic curve analysis was used to evaluate the reliability of the two methods of conidia quantification (microscope examination and qPCR assay) to predict the risk of disease being below or above a damage threshold (D(th)). In total, 142 field samples from commercial onion fields were analyzed. At damage thresholds of 5 or 10 lesions/leaf, conidia quantification with the qPCR assay was more reliable at predicting disease risk than conidia quantification based on microscope counts. The proportion of decisions where the disease was present and predicted was higher for the qPCR assay than for the microscope counts, with values of 0.95 and 0.89 compared with 0.79 and 0.81 for D(th) of 5 and 10 lesions/leaf, respectively. The proportion of decisions where the disease was present but not predicted was lower for the qPCR assay than for microscope counts, with values of 0.05 and 0.11 compared with 0.20 and 0.19 for D(th) of 5 and 10 lesions/leaf, respectively. The results demonstrated that this new qPCR assay was reliable for quantifying B. squamosa airborne inoculum in commercial onion fields and that molecular conidia quantification could be used as a component of a risk management system for Botrytis leaf blight.

  9. Transformation of inorganic P fractions of soil and plant growth promotion by phosphate-solubilizing ability of Penicillium oxalicum I1.

    PubMed

    Gong, Mingbo; Du, Peng; Liu, Xue; Zhu, Changxiong

    2014-12-01

    The solubilization of tricalcium phosphate is often considered as the standard for screening of most phosphate-solubilizing microorganisms (PSMs). However, usually the effect of large-scale application of PSM on the promotion of crop growth varies. This study presents an efficient method for screening and testing phosphate-solubilizing fungus that enhance plant growth. A fungus Penicillium oxalicum I1 (P-I1) was isolated and identified that had high ability of phosphate-solubilization and could utilize maize root exudates as sources, and propagate well in vitro and in soil. P-I1 excreted oxalic acid and reached 593.9 μg/ml, and the pH value was decreased from 6.90 to 1.65 in 26 h. The amount of P-I1 increased by 48-fold in 28 d and was maintained for 49 d in soil. PSM showed selectivity on the transformation of the different forms of phosphorus, a wide range of insoluble phosphates, such as Ca₈H₂(PO₄)₆·5H₂O, AlPO₄, FePO₄, and Ca10(PO₄)₆(OH)₂, were converted to soluble CaHPO₄in soil, and CaHPO₄was also inhibited from being converted into insoluble phosphate by P-I1. The Ca₂-P content reached 27.11 μg/g soil on day 28 at 20°C, which increased by 110.32%, and plant growth promotion was tested and verified, the results showed that maize yield increased remarkably than control after inoculated P-I1, maize yield increased maximum by 14.47%. The data presented that P-I1 appear attractive for exploring their plant growth-promoting activity and potential field application.

  10. Photodynamic inactivation of conidia of the fungus Colletotrichum abscissum on Citrus sinensis plants with methylene blue under solar radiation.

    PubMed

    Gonzales, Júlia C; Brancini, Guilherme T P; Rodrigues, Gabriela B; Silva-Junior, Geraldo José; Bachmann, Luciano; Wainwright, Mark; Braga, Gilberto Ú L

    2017-09-14

    Antimicrobial photodynamic treatment (APDT) is a promising light based approach to control diseases caused by plant-pathogenic fungi. In the present study, we evaluated the effects of APDT with the phenothiazinium photosensitizer methylene blue (MB) under solar radiation on the germination and viability of conidia of the pathogenic fungus Colletotricum abscissum (former Colletotrichum acutatum sensu lato). Experiments were performed both on petals and leaves of sweet orange (Citrus sinensis) in different seasons and weather conditions. Conidial suspensions were deposited on the leaves and petals surface, treated with the PS (25 or 50μM) and exposed to solar radiation for only 30min. The effects of APDT on conidia were evaluated by counting the colony forming units recovered from leaves and petals and by direct evaluating conidial germination on the surface of these plant organs after the treatment. To better understand the mechanistic of conidial photodynamic inactivation, the effect of APDT on the permeability of the conidial plasma membrane was assessed using the fluorescent probe propidium iodide (PI) together with flow cytometry and fluorescence microscopy. APDT with MB and solar exposure killed C. abscissum conidia and prevented their germination on both leaves and petals of citrus. Reduction of conidial viability was up to three orders of magnitude and a complete photodynamic inactivation was achieved in some of the treatments. APDT damaged the conidial plasma membrane and increased its permeability to PI. No damage to sweet orange flowers or leaves was observed after APDT. The demonstration of the efficacy of APDT on the plant host represents a further step towards the use of the method for control phytopathogens in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Hypocrea rufa/Trichoderma viride: a reassessment, and description of five closely related species with and without warted conidia

    PubMed Central

    Jaklitsch, Walter M.; Samuels, Gary J.; Dodd, Sarah L.; Lu, Bing-Sheng; Druzhinina, Irina S.

    2006-01-01

    The type species of the genus Hypocrea (Hypocreaceae, Hypocreales, Ascomycota, Fungi), H. rufa, is re-defined and epitypified using a combination of phenotype (morphology of teleomorphs and anamorphs, and characteristics in culture) and phylogenetic analyses of the translation-elongation factor 1α gene. Its anamorph, T. viride, the type species of Trichoderma, is re-described and epitypified. Eidamia viridescens is combined as Trichoderma viridescens and is recognised as one of the most morphologically and phylogenetically similar relatives of T. viride. Its teleomorph is newly described as Hypocrea viridescens. Contrary to frequent citations of H. rufa and T. viride in the literature, this species is relatively rare. Although both T. viride and T. viridescens have a wide geographic distribution, their greatest genetic diversity appears to be in Europe and North America. Hypocrea vinosa is characterised and its anamorph, T. vinosum sp. nov., is described. Conidia of T. vinosum are subglobose and warted. The new species T. gamsii is proposed. It shares eidamia-like morphology of conidiophores with T. viridescens, but it has smooth, ellipsoidal conidia that have the longest L/W ratio that we have seen in Trichoderma. Trichoderma scalesiae, an endophyte of trunks of Scalesia pedunculata in the Galapagos Islands, is described as new. It only produces conidia on a low-nutrient agar to which filter paper has been added. Additional phylogenetically distinct clades are recognised and provisionally delimited from the species here described. Trichoderma neokoningii, a T. koningii-like species, is described from a collection made in Peru on a fruit of Theobroma cacao infected with Moniliophthora roreri. PMID:18490991

  12. Human pregnancy serum contains at least two distinct proteolytic activities with the ability to degrade insulin-like growth factor binding protein-3.

    PubMed

    Bang, P; Fielder, P J

    1997-09-01

    The presence of a proteolytic activity in sera from pregnant humans and rodents capable of degrading insulin-like growth factor binding protein-3 (IGFBP-3) has been known for some time. However, the identity of this activity has remained elusive. We have attempted to purify the IGFBP-3 protease activity from pregnant human serum (PHS) using the degradation of 125I-IGFBP-3 as a marker. Following ammonium sulfate precipitation of PHS and further enrichment of active fractions by ion-exchange, protein-A Sepharose, and size-exclusion chromatography, a protease of approximately 70-90 kDa was isolated and subjected to N-terminal analysis. The N-terminal sequence was consistent with plasminogen, a known fibrinolytic enzyme. To further characterize the IGFBP-3 protease activities in both PHS and nonpregnant human serum (NHS), aliquots of serum were first enriched by polyethylene glycol-precipitation and subjected to size-exclusion chromatography. The size-separated fractions were then incubated with 125I-IGFBP-3, and proteolytic activity was measured. PHS contained two separate proteases (>150 kDa and 70-90 kDa), whereas NHS contained only one (70-90 kDa) that had a inhibitor profile similar to plasmin. However, inhibitors of plasmin had no effect on the activity of the >150-kDa protease. Plasminogen activators (PAs) greatly increased the activity of the 70- to 90-kDa protease, but had little effect on the >150-kDa protease activity. Addition of PAs greatly increased the ability of NHS to proteolyze IGFBP-3. In contrast, the ability of plasminogen-depleted plasma to degrade 125I-IGFBP-3 was not affected by the addition of PAs. Both urokinase and tissue-type PA had the ability to proteolyze IGFBP-3 and were, in contrast to the >150-kDa protease activity, inhibited by the specific PA inhibitor D-PHE-PRO-ARG chloromethyl ketone. The present data suggest that sera has the ability to proteolyze IGFBP-3, and that this ability, as demonstrated by NHS, can be regulated by protease

  13. Binding of live conidia of Aspergillus fumigatus activates in vitro-generated human Langerhans cells via a lectin of galactomannan specificity

    PubMed Central

    PERSAT, F; NOIREY, N; DIANA, J; GARIAZZO, M-J; SCHMITT, D; PICOT, S; VINCENT, C

    2003-01-01

    Aspergillus fumigatus is the most common aetiological fungus responsible for human pulmonary aspergilloses. This study investigated the primary contact between Langerhans cells (LC), corresponding to dendritic cells present in pulmonary mucosa and live conidia of A. fumigatus. LC play a key role in antigen presentation for initiation of the primary T cell response. In vitro-generated LC (iLC) were differentiated from cultured human cord blood CD34+ cells and incubated at 4°C or 37°C with fluorescein-isothiocyanate (FITC)-stained conidia or control latex beads. In vitro, conidia were shown by microscopy and cytometry to adhere to iLC in a dose- and time-dependent manner. This adhesion was not limited to iLC because interstitial dendritic and other cells also fluoresced in the presence of conidia-FITC. A lectin other than mannose receptor-type lectin was demonstrated to be responsible of conidial binding. Inhibition of binding was observed with heterologous galactomannan and EDTA, indicating a C-lectin-like receptor with galactomannan structure specificity. After binding only a few conidia were internalized in acidic vesicles, as indicated by the cessation of conidial fluorescence. Conidial binding was followed by activation and maturation of iLC, suggesting that LC present in the lung may play a role in cellular host defence against aspergilloses. PMID:12930363

  14. A phenazine-1-carboxylic acid producing polyextremophilic Pseudomonas chlororaphis (MCC2693) strain, isolated from mountain ecosystem, possesses biocontrol and plant growth promotion abilities.

    PubMed

    Jain, Rahul; Pandey, Anita

    2016-09-01

    The genus Pseudomonas is known to comprise a huge diversity of species with the ability to thrive in different habitats, including those considered as extreme environments. In the present study, a psychrotolerant, wide pH tolerant and halotolerant strain of Pseudomonas chlororaphis GBPI_507 (MCC2693), isolated from the wheat rhizosphere growing in a mountain location in Indian Himalayan Region (IHR), has been investigated for its antimicrobial potential with particular reference to phenazine production and plant growth promoting traits. GBPI_507 showed phenazine production at the temperatures ranged from 14 to 25°C. The benzene extracted compound identified as phenazine-1-carboxylic acid (PCA) through GC-MS exhibited antimicrobial properties against Gram positive bacteria and actinomycetes. The inhibition of phytopathogens in diffusible biocontrol assays was recorded in an order: Alternaria alternata>Phytophthora sp.>Fusarium solani>F. oxysporum. In volatile metabolite assays, all the pathogens, except Phytophthora sp. produced distorted colonies, characterized by restricted sporulation. The isolate also possessed other growth promoting and biocontrol traits including phosphate solubilization and production of siderophores, HCN, ammonia, and lytic enzymes (lipase and protease). Molecular studies confirmed production of PCA by the bacterium GBPI_507 through presence of phzCD and phzE genes in its genome. The polyextremophilic bacterial strain possesses various important characters to consider it as a potential agent for field applications, especially in mountain ecosystem, for sustainable and eco-friendly crop production. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. 11th Yahya Cohen Memorial Lecture: An in vivo comparative study of the ability of derived mesenchymal stem cells in the treatment of partial growth arrest.

    PubMed

    Hui, James H P; Li, Li; Ouyang, Hong-Wei; Teo, Yee-Hong; Lee, Eng-Hin

    2009-01-01

    Few in vivo studies had previously been attempted in reaffirming the in vitro data in current literature. This study evaluated the ability of mesenchymal stem cells (MSCs) isolated from bone marrow, periosteum and fat to treat partial growth arrest in immature New Zealand white (NZW) rabbits. A physeal arrest model in an immature rabbit was created. The bony bridge was excised 3 weeks later, and MSCs from various sources were transferred into the physeal defect of different rabbits. Group I consisted of bone marrow-derived MSCs, Group II: periosteumderived MSCs, Group III: fat-derived MSCs. Contra-lateral tibiae, without undergoing operation, served as self-control. The animals were subsequently sacrificed, with radiological and histological analyses performed. All MSCs demonstrated chondrogenic and osteogenic differentiation potentials in vitro. In correction of varus angulation groups I and II exhibited superior results when compared to group III (P <0.05). The length discrepancies between operated and normal tibiae in groups I, II and III were significantly corrected when compared to the control group (P <0.01). In conclusion, bone marrow and periosteum derived stem cells provided better correction of physeal arrest in rabbits. The source of MSCs itself could influence the success in the treatment of growth arrest.

  16. Coloration signals the ability to cope with elevated stress hormones: effects of corticosterone on growth of barn owls are associated with melanism.

    PubMed

    Almasi, B; Roulin, A; Korner-Nievergelt, F; Jenni-Eiermann, S; Jenni, L

    2012-06-01

    Stressful situations during development can shape the phenotype for life by provoking a trade-off between development and survival. Stress hormones, mainly glucocorticoids, play an important orchestrating role in this trade-off. Hence, how stress sensitive an animal is critically determines the phenotype and ultimately fitness. In several species, darker eumelanic individuals are less sensitive to stressful conditions than less eumelanic conspecifics, which may be due to the pleiotropic effects of genes affecting both coloration and physiological traits. We experimentally tested whether the degree of melanin-based coloration is associated with the sensitivity to an endocrine response to stressful situations in the barn owl. We artificially administered the mediator of a hormonal stress response, corticosterone, to nestlings to examine the prediction that corticosterone-induced reduction in growth rate is more pronounced in light eumelanic nestlings than in darker nest mates. To examine whether such an effect may be genetically determined, we swapped hatchlings between randomly chosen pairs of nests. We first showed that corticosterone affects growth and, thus, shapes the phenotype. Second, we found that under corticosterone administration, nestlings with large black spots grew better than nestlings with small black spots. As in the barn owl the expression of eumelanin-based coloration is heritable and not sensitive to environmental conditions, it is therefore a reliable, genetically based sign of the ability to cope with an increase in blood corticosterone level.

  17. The pmr gene, encoding a Ca2+-ATPase, is required for calcium and manganese homeostasis and normal development of hyphae and conidia in Neurospora crassa.

    PubMed

    Bowman, Barry J; Abreu, Stephen; Johl, Jessica K; Bowman, Emma Jean

    2012-11-01

    The pmr gene is predicted to encode a Ca(2+)-ATPase in the secretory pathway. We examined two strains of Neurospora crassa that lacked PMR: the Δpmr strain, in which pmr was completely deleted, and pmr(RIP), in which the gene was extensively mutated. Both strains had identical, complex phenotypes. Compared to the wild type, these strains required high concentrations of calcium or manganese for optimal growth and had highly branched, slow-growing hyphae. They conidiated poorly, and the shape and size of the conidia were abnormal. Calcium accumulated in the Δpmr strains to only 20% of the wild-type level. High concentrations of MnCl(2) (1 to 5 mM) in growth medium partially suppressed the morphological defects but did not alter the defect in calcium accumulation. The Δpmr Δnca-2 double mutant (nca-2 encodes a Ca(2+)-ATPase in the plasma membrane) accumulated 8-fold more calcium than the wild type, and the morphology of the hyphae was more similar to that of wild-type hyphae. Previous experiments failed to show a function for nca-1, which encodes a SERCA-type Ca(2+)-ATPase in the endoplasmic reticulum (B. J. Bowman, S. Abreu, E. Margolles-Clark, M. Draskovic, and E. J. Bowman, Eukaryot. Cell 10:654-661, 2011). The pmr(RIP) Δnca-1 double mutant accumulated small amounts of calcium, like the Δpmr strain, but exhibited even more extreme morphological defects. Thus, PMR can apparently replace NCA-1 in the endoplasmic reticulum, but NCA-1 cannot replace PMR. The morphological defects in the Δpmr strain are likely caused, in part, by insufficient concentrations of calcium and manganese in the Golgi compartment; however, PMR is also needed to accumulate normal levels of calcium in the whole cell.

  18. Proteomic analysis of conidia germination in Fusarium oxysporum f. sp. cubense tropical race 4 reveals new targets in ergosterol biosynthesis pathway for controlling Fusarium wilt of banana.

    PubMed

    Deng, Gui-Ming; Yang, Qiao-Song; He, Wei-Di; Li, Chun-Yu; Yang, Jing; Zuo, Cun-Wu; Gao, Jie; Sheng, Ou; Lu, Shao-Yun; Zhang, Sheng; Yi, Gan-Jun

    2015-09-01

    Conidial germination is a crucial step of the soilborne fungus Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), a most important lethal disease of banana. In this study, a total of 3659 proteins were identified by isobaric tags for relative and absolute quantitation (iTRAQ)-based comparative proteomic approach, of which 1009 were differentially expressed during conidial germination of the fungus at 0, 3, 7, and 11 h. Functional classification and bioinformatics analysis revealed that the majority of the differentially expressed proteins are involved in six metabolic pathways. Particularly, all differential proteins involved in the ergosterol biosynthesis pathway were significantly upregulated, indicating the importance of the ergosterol biosynthesis pathway to the conidial germination of Foc TR4. Quantitative RT-PCR, western blotting, and in vitro growth inhibition assay by several categories of fungicides on the Foc TR4 were used to validate the proteomics results. Four enzymes, C-24 sterol methyltransferase (ERG6), cytochrome P450 lanosterol C-14α-demethylase (EGR11), hydroxymethylglutaryl-CoA synthase (ERG13), and C-4 sterol methyl oxidase (ERG25), in the ergosterol biosynthesis pathway were identified and verified, and they hold great promise as new targets for effective inhibition of Foc TR4 early growth in controlling Fusarium wilt of banana. To the best of our knowledge, this report represents the first comprehensive study on proteomics profiling of conidia germination in Foc TR4. It provides new insights into a better understanding of the developmental processes of Foc TR4 spores. More importantly, by host plant-induced gene silencing (HIGS) technology, the new targets reported in this work allow us to develop novel transgenic banana leading to high protection from Fusarium wilt and to explore more effective antifungal drugs against either individual or multiple target proteins of Foc TR4.

  19. Densely adherent growth mode, rather than extracellular polymer substance matrix build-up ability, contributes to high resistance of Staphylococcus epidermidis biofilms to antibiotics.

    PubMed

    Qu, Yue; Daley, Andrew J; Istivan, Taghrid S; Rouch, Duncan A; Deighton, Margaret A

    2010-07-01

    (i) To evaluate the role of the adherent growth mode and extracellular polymer substance build-up in biofilm resistance to antibiotics. (ii) To re-assess various mechanisms leading to biofilm resistance to antibiotics. We compared the biofilm MICs, biofilm MBCs using the viable count method, biofilm MBCs based on broth recovery methods and minimum biofilm eradication concentrations (MBECs) of antistaphylococcal antibiotics for multilayer biofilms formed by 'biofilm-positive' S. epidermidis strains and monolayer biofilms formed by their 'biofilm-negative' mutants/variants. Bacterial densities and the quantity of persister cells in both multilayer and monolayer biofilms were assessed to evaluate their roles in biofilm resistance. Monolayer and multilayer biofilms presented similar susceptibilities to multiple antibiotics, based on biofilm MIC, broth recovery-based biofilm MBC and MBEC results. Multilayer biofilms demonstrated higher viable count-based MBCs than monolayer biofilms. Both monolayer and multilayer biofilms had very high bacterial densities of approximately 10(11-12) cfu/mL. Persister cells were found in both monolayer and multilayer biofilms, but not in planktonic cultures at log phase. The presence of persister cells in monolayer and multilayer biofilms appeared to be strain and antibiotic dependent. The adherent growth mode, rather than the ability to build up a typical multilayer biofilm structure, contributes to the high resistance of biofilms to antibiotics, and therefore might be the main virulence factor of coagulase-negative staphylococci (CoNS) with respect to antibiotic resistance. The presence of persister cells in CoNS biofilms plays an important role in antibiotic resistance. Growth at high bacterial densities is another significant factor in biofilm resistance.

  20. Relationship Between Organization of Mammary Tumors and the Ability of Tumor Cells to Replicate Mammary Tumor Virus and to Recognize Growth-Inhibitory Contact Signals In Vitro

    PubMed Central

    McGrath, Charles M.; Nandi, S.; Young, Lawrence

    1972-01-01

    Mammary tumor virus (MTV) replication was confined primarily to cells organized as acini in intact mouse mammary glands. Primary mammary tumors maintained a high degree of acinar organization and cells therein continued to replicate MTV vegetatively. Nonacinar mammary cells, derived by serial transplantation of acinar tumor cells, no longer actively replicated MTV. This suggests that phenotypic differences exist among mammary epithelial cells in their ability to support virus replication, that a fundamental relationship exists between the organization of epithelium for secretion and active virus replication, and that this relationship is not altered as a primary consequence of neoplastic transformation. Mammary epithelial cells from pregnant, non-tumor-bearing, MTV-infected BALB/cfC3H mice or from acinar mammary tumors from a number of mouse strains were grown in primary monolayer cultures. Such cell cultures under the influence of insulin and cortisol exhibited the ability to organize into discrete three-dimensional structures called “domes.” MTV replication in such cultures took place primarily in cells within the organized domes. Cells cultured from nonacinar tumors did not exhibit any propensity to organize into domes, nor did they replicate MTV in primary culture. This suggests that the cell organizational requirement for MTV replication observed in vivo is conserved in primary culture. Dome formation is not an effect of virus replication, as cells from uninfected BALB/c animals organized into domes in culture without concomitant MTV replication. Growth-regulating signals, exerted between contiguous cells in cultures of non-MTV-infected mammary epithelium, were not modified by the occurrence of active virus replication nor as a direct consequence of neoplastic transformation. Cells derived from nontumor BALB/cfC3H glands and from spontaneous tumors exhibited cell growth kinetics, saturation densities, and deoxyribonucleic acid synthesis kinetics nearly

  1. Impact of urban air pollution on the allergenicity of Aspergillus fumigatus conidia: Outdoor exposure study supported by laboratory experiments.

    PubMed

    Lang-Yona, Naama; Shuster-Meiseles, Timor; Mazar, Yinon; Yarden, Oded; Rudich, Yinon

    2016-01-15

    Understanding the chemical interactions of common allergens in urban environments may help to decipher the general increase in susceptibility to allergies observed in recent decades. In this study, asexual conidia of the allergenic mold Aspergillus fumigatus were exposed to air pollution under natural (ambient) and controlled (laboratory) conditions. The allergenic activity was measured using two immunoassays and supported by a protein mass spectrometry analysis. The allergenicity of the conidia was found to increase by 2-5 fold compared to the control for short exposure times of up to 12h (accumulated exposure of about 50 ppb NO2 and 750 ppb O3), possibly due to nitration. At higher exposure times, the allergenicity increase lessened due to protein deamidation. These results indicate that during the first 12h of exposure, the allergenic potency of the fungal allergen A. fumigatus in polluted urban environments is expected to increase. Additional work is needed in order to determine if this behavior occurs for other allergens. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Expression and arrangement of extracellular matrix proteins in the lungs of mice infected with Paracoccidioides brasiliensis conidia

    PubMed Central

    González, Angel; Lenzi, Henrique Leonel; Motta, Ester Maria; Caputo, Luzia; Restrepo, Angela; Cano, Luz Elena

    2008-01-01

    Extracellular matrix (ECM) proteins are important modulators of migration, differentiation and proliferation for the various cell types present in the lungs; they influence the immune response as well as participate in the adherence of several fungi including Paracoccidioides brasiliensis. The expression, deposition and arrangement of ECM proteins such as laminin, fibronectin, fibrinogen, collagen and proteoglycans in the lungs of mice infected with P. brasiliensis conidia has been evaluated in this study, together with the elastic fibre system. Lungs of BALB/c mice infected with P. brasiliensis conidia were analysed for the different ECM proteins by histological and immunohistochemical procedures at different times of infection. In addition, laser scanning confocal microscopy and scanning electron microscopy were used. During the early periods, the lungs of infected animals showed an inflammatory infiltrate composed mainly of polymorphonuclear neutrophils (PMNs) and macrophages, while during the later periods, mice presented a chronic inflammatory response with granuloma formation. Re-arrangement and increased expression of all ECM proteins tested were observed throughout all studied periods, especially during the occurrence of inflammatory infiltration and formation of the granuloma. The elastic fibre system showed an elastolysis process in all experiments. In conclusion, this study provides new details of pulmonary ECM distribution during the course of paracoccidioidomycosis. PMID:18336528

  3. Effects of whole-stream nutrient enrichment on the concentration and abundance of aquatic hyphomycete conidia in transport.

    PubMed

    Gulis, Vladislav; Suberkropp, Keller

    2004-01-01

    The concentrations and relative abundances of aquatic hyphomycete conidia in water were followed during a three-year study in two headwater streams at Coweeta Hydrologic Laboratory, North Carolina, using the membrane-filtration technique. After a one-year pretreatment period, one of the streams was enriched continuously with inorganic nutrients (N+P) for two years while the other stream served as the reference. This ecosystem-level nutrient manipulation resulted in concentrations of aquatic hyphomycete conidia in the water of the treated stream that were 4.5-6.9 times higher than the concentrations observed during the pretreatment period and in the reference stream. Nutrient enrichment led to an increase in the number of fungal species detected on each sampling date. Changes in dominance patterns and relative abundances of individual species also were detected after treatment. Nutrient addition stimulates the reproductive activity of aquatic hyphomycetes, their colonization success and fungal-mediated leaf-litter decomposition. Such changes in the activity of the fungal community might affect higher trophic levels in lotic ecosystems.

  4. Effects of resveratrol on the ultrastructure of Botrytis cinerea conidia and biological significance in plant/pathogen interactions.

    PubMed

    Adrian, Marielle; Jeandet, Philippe

    2012-12-01

    Many roles have been ascribed to stilbenes, namely as antimicrobial, deterrent or repellent compounds in plants, protecting them from attacks by fungi, bacteria, nematodes or herbivores, acting both as constitutive and active defense (phytoalexin) compounds. More recently, stilbenes (especially resveratrol and its derivatives) were acclaimed for their wondrous effects and wide range of purported healing and preventive powers as cardioprotective, antitumor, neuroprotective and antioxidant agents. Although there is a huge number of works concerning the role of resveratrol in human health, reports on the antifungal activity of this compound are still scarce. This study was thus conducted in order to investigate the toxicity of resveratrol at an ultra- structural level to dormant conidia of Botrytis cinerea, the causal microorganism for gray mold. In grapevine particularly, this disease can affect all the green organs but is particularly damaging for ripening berries. Observations using transmission electron microscopy showed the occurrence of damages on conidia treated with sub-lethal doses, that is, 60μg/mL (2.6×10(-4)M) of resveratrol, a concentration usually reached in grapevine leaves and grape berries challenged by this pathogen. These results provide further data about the overall mode of action of this phytoalexin and its role in the B. cinerea/grapevine interaction.

  5. Effect of exposure method to Beauveria bassiana and conidia concentration on mortality, mycosis, and sporulation in cadavers of Chilo partellus (Lepidoptera: Pyralidae).

    PubMed

    Tefera, Tadele; Pringle, K L

    2003-10-01

    The effects of exposure methods, conidial concentrations, and temperature on mortality, mycosis and sporulation in second instar Chilo partellus cadavers infected by Beauveria bassiana was investigated in laboratory studies. Larvae directly sprayed with conidia, exposed to conidia-treated leaves, and dipped into conidial suspension resulted in high mortality (98-100%). The longest LT50 (3.5 days) and days to mortality (2.6 days) were observed in the treated-leaves exposure method. The shortest LT50 (1 day) and days to mortality (1 day) were recorded for the dipping method. With increasing conidial concentrations, there were decreasing LT50 and days to mortality. Larvae exposed to treated leaves and larvae directly sprayed with conidial suspensions produced high mycoses in cadavers. Exposure of larvae to treated-leaves resulted in high sporulation. At lower concentrations of conidia, both mycosis and sporulation in cadavers were high. The optimum temperature for mycosis was 20 and 15 degrees C for sporulation.

  6. Male poplars have a stronger ability to balance growth and carbohydrate accumulation than do females in response to a short-term potassium deficiency.

    PubMed

    Yang, Yanni; Jiang, Hao; Wang, Maolin; Korpelainen, Helena; Li, Chunyang

    2015-12-01

    Potassium (K) deficiency influences plant performance, such as ion uptake and carbohydrate transport. However, little is known about differences between males and females in response to K deficiency. In this study, dry matter accumulation, photosynthetic capacity, allocation patterns of K(+) , Na(+) and carbohydrates, and ultrastructural changes in males and females of Populus cathayana exposed to K deficiency were investigated. The results indicated that males maintained a significantly higher K(+) content and K(+) /Na(+) ratio in leaves and stems than did females under K deficiency. Moreover, K deficiency significantly increased the sucrose content of females, whereas no significant effect on males was detected. In addition, a comparative analysis showed that males allocated more resources to roots, while females allocated more to leaves, which resulted in sexually different root/shoot (R/S) ratios. Transmission electron microscopic (TEM) observations showed that males suffered fewer injuries than did females. These results suggested that males have a better ability to cope with K deficiency. In addition, the combined effects of salinity and K deficiency on poplars were studied. The results indicated that salt stress aggravates the negative effects caused by K deficiency. Taken together, our study provided evidence for gender-specific strategies in ion and carbohydrate allocation in poplars exposed to a short-term K deficiency. In leaves and stems, the lower K(+) accumulation inhibited sucrose translocation and resulted in a decreased R/S ratio, which may contribute to males having a stronger ability to balance growth and carbohydrate accumulation when compared with females. © 2015 Scandinavian Plant Physiology Society.

  7. Microstructure and refinement performance of Al-Ti-C master alloy: Effect of excess Ti on the growth and nucleating ability of TiC particles

    NASA Astrophysics Data System (ADS)

    Svynarenko, Kateryna; Zhang, Yubo; Jie, Jinchuan; Kutsova, Valentyna; Li, Tingju

    2017-09-01

    Al-5Ti-0.2C, Al-0.8Ti-0.2C, Al-8Ti-2C, and Al-10Ti master alloys were prepared and used to investigate the influence of excess Ti on the growth of TiC particles and its ability to nucleate Al-grains. The results of a microstructure analysis of TiC-containing alloys and refined CPAl were interrelated to the results of a refinement test. It was found that the presence of excess Ti is essential at the stage of master alloy preparation, as it facilitates the growth and uniform distribution of TiC within the structure. In Al-5Ti-0.2C alloy containing excess Ti, carbide particles grow faster and to a higher extent (from 0.29 μm to 0.44 μm) compared to Al-0.8Ti-0.2C alloy produced without excess Ti (from 0.29 μm to 0.32 μm). The results support the "Ti-transition zone theory" as the mechanism of grain refinement by TiC-containing master alloys. The refinement performance of Al-5Ti-0.2C is superior compared to the one achieved by adding Al-8Ti-2C and Al-10Ti master alloys in corresponding concentrations. For the TiC particles to become favourable nucleating sites, they must undergo certain interaction with excess Ti at the stage of master alloy preparation.

  8. Comparative study of the ability of mesenchymal stem cells derived from bone marrow, periosteum, and adipose tissue in treatment of partial growth arrest in rabbit.

    PubMed

    Hui, James H P; Li, Li; Teo, Yee-Hong; Ouyang, Hong-Wei; Lee, Eng-Hin

    2005-01-01

    This study evaluates the ability of MSCs isolated from different origins--bone marrow, periosteum, or fat--to treat partial growth arrest in immature (6-week-old) New Zealand White rabbits. Up to 50% of the medial half of the proximal physis of the tibia was excised in these New Zealand White rabbits. Three weeks later, the bony bridge was excised, and fibrin glue with and without MSCs were transferred into the physeal defect of different rabbits. Contralateral tibias, without undergoing operation, served as self-control. Four groups of rabbits were involved in the study. Each group was injected separately with bone marrow-derived MSCs (group I), periosteum-derived MSCs (group II), fat-derived MSCs (group III), and fibrin glue alone (control, group IV). The rabbits were killed 8 and 16 weeks postoperatively. Clinical, radiological, and histological analyses were subsequently performed. Similar proliferative rates for three MSCs were demonstrated on days 4, 7, and 11 of primary culture. However, MSCs derived from bone-marrow and periosteum appeared to be more homogeneous than that from fat. All MSCs demonstrated chondrogenic and osteogenic differentiation potentials in vitro. The tibias in groups I and II showed significant correction of varus angulation at 16 weeks. However, the varus angulation in group III remained significantly obvious when compared with group I (p < 0.05). The length discrepancies between operated and normal tibiae in groups I, II, and III were significantly corrected compared with control (p < 0.01). In conclusion, bone-marrow and periosteum yielded more homogenous MSCs than fat, providing better correction of physeal arrest in rabbits. The source of MSCs itself could influence the success in the treatment of growth arrest.

  9. Growth and ethanol fermentation ability on hexose and pentose sugars and glucose effect under various conditions in thermotolerant yeast Kluyveromyces marxianus.

    PubMed

    Rodrussamee, Nadchanok; Lertwattanasakul, Noppon; Hirata, Katsushi; Suprayogi; Limtong, Savitree; Kosaka, Tomoyuki; Yamada, Mamoru

    2011-05-01

    Ethanol fermentation ability of the thermotolerant yeast Kluyveromyces marxianus, which is able to utilize various sugars including glucose, mannose, galactose, xylose, and arabinose, was examined under shaking and static conditions at high temperatures. The yeast was found to produce ethanol from all of these sugars except for arabinose under a shaking condition but only from hexose sugars under a static condition. Growth and sugar utilization rate under a static condition were slower than those under a shaking condition, but maximum ethanol yield was slightly higher. Even at 40°C, a level of ethanol production similar to that at 30°C was observed except for galactose under a static condition. Glucose repression on utilization of other sugars was observed, and it was more evident at elevated temperatures. Consistent results were obtained by the addition of 2-deoxyglucose. The glucose effect was further examined at a transcription level, and it was found that KmGAL1 for galactokinase and KmXYL1 for xylose reductase for galactose and xylose/arabinose utilization, respectively, were repressed by glucose at low and high temperatures, but KmHXK2 for hexokinase was not repressed. We discuss the possible mechanism of glucose repression and the potential for utilization of K. marxianus in high-temperature fermentation with mixed sugars containing glucose.

  10. CPPU elevates photosynthetic abilities, growth performances and yield traits in salt stressed rice (Oryza sativa L. spp. indica) via free proline and sugar accumulation.

    PubMed

    Gashaw, Arega; Theerawitaya, Cattarin; Samphumphuang, Thapanee; Cha-um, Suriyan; Supaibulwatana, Kanyaratt

    2014-01-01

    Application of N-2-(chloro-4-pyridyl)-N-phenyl urea (CPPU) to salt susceptible cultivar of indica rice (cv. PTT1) effected on free proline and soluble sugar accumulation and regulated the physio-morphological responses when subjected to salt stress condition was firstly demonstrated in this study. Soluble sugars, including sucrose, glucose and fructose, in leaf blade and leaf sheath were enriched in 0.1 mM CPPU pretreated plants subsequently exposed to 16.6 dS m(-1) NaCl for 10 days. In the long period (15 days) salt stress, free proline content in the leaf blade and leaf sheath were evidently peaked to act as osmotic adjustment in the salt-stressed plants. In addition, the photosynthetic pigments, including chlorophyll a, chlorophyll b, total chlorophyll and total carotenoids, were maintained by the functional regulation of soluble sugar and free proline in the cellular levels, thereby leading to higher net photosynthetic rate. Further, the stomatal closure and transpiration rate in CPPU pretreated plants were retained under salt stress, thereby resulting in alleviation of growth performance and yield traits. This study suggested that exogenous application of CPPU may alternatively play effective role to improve the salt tolerant abilities of salt susceptible rice crop.

  11. Growth response, nutrient and mineral retention, bone mineralisation and walking ability of broiler chickens fed with dietary inclusion of various unconventional mineral sources.

    PubMed

    Oso, A O; Idowu, A A; Niameh, O T

    2011-08-01

    Growth response, nutrient and mineral retention, bone mineral content and walking ability of broiler chicken fed dietary inclusion of various unconventional calcium sources were studied using 160-day-old broilers. Four isonitrogenous, isocaloric diets balanced for Ca and P were formulated such that oyster shell, snail shell, wood ash and limestone were used as main non-phytate (Ca from other sources apart from plant) calcium sources. Each dietary treatment consisted of 40 birds replicated four times with 10 birds per replicate. A single diet was fed to the broilers throughout the duration of the study which lasted for 8 weeks. Broilers fed diet containing oyster shell as calcium sources recorded the highest (p < 0.05) feed intake of 5863.30 g, while those fed diet containing limestone consumed the least intake (p < 0.05) of 5432.56 g. Occurrence of lameness and evidences of gaits were highest (p < 0.05) for broilers fed diet containing wood ash. Lowest (p < 0.05) Ca and ash retention were recorded for broiler fed diet containing wood ash as Ca sources. Similar tibia ash values were recorded for broilers fed oyster shell, snail shell and limestone. Wood ash inclusion resulted in a low Ca availability hence its inclusion in feeds for broilers should be discouraged.

  12. The quick and the deadly: growth vs virulence in a seed bank pathogen.

    PubMed

    Meyer, Susan E; Stewart, Thomas E; Clement, Suzette

    2010-07-01

    *We studied the relationship between virulence (ability to kill nondormant Bromus tectorum seeds) and mycelial growth index in the necrotrophic seed pathogen Pyrenophora semeniperda. Seed pathosystems involving necrotrophs differ from those commonly treated in traditional evolution-of-virulence models in that host death increases pathogen fitness by preventing germination, thereby increasing available resources. Because fast-germinating, nondormant B. tectorum seeds commonly escape mortality, we expected virulence to be positively correlated with mycelial growth index. *We performed seed inoculations using conidia from 78 pathogen isolates and scored subsequent mortality. For a subset of 40 of these isolates, representing a range of virulence phenotypes, we measured mycelial growth index. *Virulence varied over a wide range (3-43% seed mortality) and was significantly negatively correlated with mycelial growth index (R(2) = 0.632). More virulent isolates grew more slowly than less virulent isolates. *We concluded that there is an apparent tradeoff between virulence and growth in this pathogen, probably because the production of toxins necessary for necrotrophic pathogenesis competes with metabolic processes associated with growth. Variation in both virulence and growth rate in this pathosystem may be maintained in part by seasonal variation in the relative abundance of rapidly germinating vs dormant host seeds available to the pathogen.

  13. Growth

    Treesearch

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  14. A soluble fucose-specific lectin from Aspergillus fumigatus conidia--structure, specificity and possible role in fungal pathogenicity.

    PubMed

    Houser, Josef; Komarek, Jan; Kostlanova, Nikola; Cioci, Gianluca; Varrot, Annabelle; Kerr, Sheena C; Lahmann, Martina; Balloy, Viviane; Fahy, John V; Chignard, Michel; Imberty, Anne; Wimmerova, Michaela

    2013-01-01

    Aspergillus fumigatus is an important allergen and opportunistic pathogen. Similarly to many other pathogens, it is able to produce lectins that may be involved in the host-pathogen interaction. We focused on the lectin AFL, which was prepared in recombinant form and characterized. Its binding properties were studied using hemagglutination and glycan array analysis. We determined the specificity of the lectin towards l-fucose and fucosylated oligosaccharides, including α1-6 linked core-fucose, which is an important marker for cancerogenesis. Other biologically relevant saccharides such as sialic acid, d-mannose or d-galactose were not bound. Blood group epitopes of the ABH and Lewis systems were recognized, Le(Y) being the preferred ligand among others. To provide a correlation between the observed functional characteristics and structural basis, AFL was crystallized in a complex with methyl-α,L-selenofucoside and its structure was solved using the SAD method. Six binding sites, each with different compositions, were identified per monomer and significant differences from the homologous AAL lectin were found. Structure-derived peptides were utilized to prepare anti-AFL polyclonal antibodies, which suggested the presence of AFL on the Aspergillus' conidia, confirming its expression in vivo. Stimulation of human bronchial cells by AFL led to IL-8 production in a dose-dependent manner. AFL thus probably contributes to the inflammatory response observed upon the exposure of a patient to A. fumigatus. The combination of affinity to human epithelial epitopes, production by conidia and pro-inflammatory activity is remarkable and shows that AFL might be an important virulence factor involved in an early stage of A. fumigatus infection.

  15. Interactions of Chemical Additives, pH, and Temperature on Conidia Germination and Virulence of Colletotrichum truncatum, a Bioherbicide of Sesbania exaltata

    USDA-ARS?s Scientific Manuscript database

    We studied several factors that influence conidial germination and pathogenicity of the fungus Colletotrichum truncatum, which is a potential bioherbicide for hemp sesbania. The conidia germinated on 2% water agar over the pH range of 3.5 to 9.0, and the optimal pH for germination depended upon the ...

  16. Application of hydrophilic-lypophilic balance (HLB) number to optimize a compatible non-ionic surfactant for dried aerial conidia of Beauveria bassiana

    USDA-ARS?s Scientific Manuscript database

    The hydrophilic-lipophilic balance (HLB) number system was used to optimize a compatible non-ionic surfactant, TDA(polyoxyethylene tridecyl ether) in formulations for two Beauveria bassiana strains, NI8 and GHA. The optimal HLB number for TDA was determined on the basis of wetting times for conidia...

  17. Impact of two treatments of a formulation of Beauveria bassiana (Deuteromycota: Hyphomycetes) conidia on Varroa mites (Acari: Varroidae) and on honeybee (Hymenoptera: Apidae) colony health.

    PubMed

    Meikle, William G; Mercadier, Guy; Holst, Niels; Girod, Vincent

    2008-12-01

    Bee colonies in southern France were treated with conidia (asexual spores) from two strains of Beauveria bassiana, an entomopathogenic fungus. One strain was commercial (GHA) and the other had been isolated from Varroa mites in the region (Bb05002). Objectives were to evaluate treatment effect on colony weight, adult bee mass, capped brood, and on Varroa fall onto sticky boards. Treatments included conidia formulated with either carnauba or candelilla wax powder, candelilla wax powder alone, or control; in two treatment groups formulation was applied a second time after one week. Treatment did not affect colony health. Colonies treated twice with Bb05002 conidia and carnauba wax powder had significantly higher mite fall compared to colonies treated with blank candelilla wax powder. The proportion of fallen mites that were infected in both conidia treatments was higher than controls for 18 days after the second treatment. The number of fungal propagules on the bees themselves remained elevated for about 14 days after the second treatment. These results were compared to published results from previous experiments with regard to infection duration.

  18. Impact of two treatments of a formulation of Beauveria bassiana (Deuteromycota: Hyphomycetes) conidia on Varroa mites (Acari: Varroidae) and on honeybee (Hymenoptera: Apidae) colony health

    USDA-ARS?s Scientific Manuscript database

    Bee colonies in southern France were treated with conidia from 2 strains of Beauveria bassiana – one commercial (GHA) and the other isolated from Varroa mites in the region (Bb05002). Objectives were to evaluate treatment effect on colony weight, adult bee mass, capped brood, and on Varroa fall onto...

  19. A strain of Saccharomyces cerevisiae evolved for fermentation of lignocellulosic biomass displays improved growth and fermentative ability in high solids concentrations and in the presence of inhibitory compounds

    PubMed Central

    2011-01-01

    Background Softwoods are the dominant source of lignocellulosic biomass in the northern hemisphere, and have been investigated worldwide as a renewable substrate for cellulosic ethanol production. One challenge to using softwoods, which is particularly acute with pine, is that the pretreatment process produces inhibitory compounds detrimental to the growth and metabolic activity of fermenting organisms. To overcome the challenge of bioconversion in the presence of inhibitory compounds, especially at high solids loading, a strain of Saccharomyces cerevisiae was subjected to evolutionary engineering and adaptation for fermentation of pretreated pine wood (Pinus taeda). Results An industrial strain of Saccharomyces, XR122N, was evolved using pretreated pine; the resulting daughter strain, AJP50, produced ethanol much more rapidly than its parent in fermentations of pretreated pine. Adaptation, by preculturing of the industrial yeast XR122N and the evolved strains in 7% dry weight per volume (w/v) pretreated pine solids prior to inoculation into higher solids concentrations, improved fermentation performance of all strains compared with direct inoculation into high solids. Growth comparisons between XR122N and AJP50 in model hydrolysate media containing inhibitory compounds found in pretreated biomass showed that AJP50 exited lag phase faster under all conditions tested. This was due, in part, to the ability of AJP50 to rapidly convert furfural and hydroxymethylfurfural to their less toxic alcohol derivatives, and to recover from reactive oxygen species damage more quickly than XR122N. Under industrially relevant conditions of 17.5% w/v pretreated pine solids loading, additional evolutionary engineering was required to decrease the pronounced lag phase. Using a combination of adaptation by inoculation first into a solids loading of 7% w/v for 24 hours, followed by a 10% v/v inoculum (approximately equivalent to 1 g/L dry cell weight) into 17.5% w/v solids, the final

  20. Musical ability.

    PubMed

    Sloboda, J

    1993-01-01

    Musical ability is the ability to 'make sense' of music, and develops in most people over the first decade of life through normal enculturation. Whether this ability is developed to a high level usually depends on the decision to start learning a musical instrument, which forces high levels of focused cognitive engagement (practice) with musical materials. Performance ability has both technical and expressive aspects. These aspects are not always developed equally well. Factors contributing to the development of a well-balanced musical performer include (a) lengthy periods of engagement with music through practice and exploration, (b) high levels of material and emotional support from parents and other adults, (c) relationships with early teachers characterized by warmth and mutual liking, and (d) early experiences with music that promote, rather than inhibit, intense sensuous/affective experiences. It is argued that much formal education inhibits the development of musical ability through over-emphasis on assessment, creating performance anxiety, coupled with class and sex stereotyping of approved musical activities. Early free exploration of a medium is a necessity for the development of high levels of musicality.

  1. Regulation of physicochemical properties, osteogenesis activity, and fibroblast growth factor-2 release ability of β-tricalcium phosphate for bone cement by calcium silicate.

    PubMed

    Su, Ching-Chuan; Kao, Chia-Tze; Hung, Chi-Jr; Chen, Yi-Jyun; Huang, Tsui-Hsien; Shie, Ming-You

    2014-04-01

    β-Tricalcium phosphate (β-TCP) is an osteoconductive material. For this research we have combined it with a low degradation calcium silicate (CS) to enhance its bioactive and osteostimulative properties. To check its effectiveness, a series of β-TCP/CS composites with different ratios were prepared to make new bioactive and biodegradable biocomposites for bone repair. Formation of bone-like apatite, the diametral tensile strength, and weight loss of composites were considered before and after immersion in simulated body fluid (SBF). In addition, we also examined the effects of fibroblast growth factor-2 (FGF-2) released from β-TCP/CS composites and in vitro human dental pulp cell (hDPC) and studied its behavior. The results showed that the apatite deposition ability of the β-TCP/CS composites was enhanced as the CS content was increased. For composites with more than 50% CS contents, the samples were completely covered by a dense bone-like apatite layer. At the end of the immersion point, weight losses of 19%, 24%, 33%, 42%, and 51% were observed for the composites containing 0%, 30%, 50%, 70% and 100% β-TCP cements, respectively. In vitro cell experiments show that the CS-rich composites promote human dental pulp cell (hDPC) proliferation and differentiation. However, when the CS quantity in the composite is less than 70%, the amount of cells and osteogenesis protein of hDPCs was stimulated by FGF-2 released from β-TCP/CS composites. The combination of FGF-2 in degradation of β-TCP and osteogenesis of CS gives a strong reason to believe that these calcium-based composite cements may prove to be promising bone repair materials.

  2. Identification of growth stage molecular markers in Trichoderma sp. 'atroviride type B' and their potential application in monitoring fungal growth and development in soil.

    PubMed

    Mendoza-Mendoza, Artemio; Steyaert, Johanna; Nieto-Jacobo, Maria Fernanda; Holyoake, Andrew; Braithwaite, Mark; Stewart, Alison

    2015-11-01

    Several members of the genus Trichoderma are biocontrol agents of soil-borne fungal plant pathogens. The effectiveness of biocontrol agents depends heavily on how they perform in the complex field environment. Therefore, the ability to monitor and track Trichoderma within the environment is essential to understanding biocontrol efficacy. The objectives of this work were to: (a) identify key genes involved in Trichoderma sp. 'atroviride type B' morphogenesis; (b) develop a robust RNA isolation method from soil; and (c) develop molecular marker assays for characterizing morphogenesis whilst in the soil environment. Four cDNA libraries corresponding to conidia, germination, vegetative growth and conidiogenesis were created, and the genes identified by sequencing. Stage specificity of the different genes was confirmed by either Northern blot or quantitative reverse-transcriptase PCR (qRT-PCR) analysis using RNA from the four stages. con10, a conidial-specific gene, was observed in conidia, as well as one gene also involved in subsequent stages of germination (L-lactate/malate dehydrogenase encoding gene). The germination stage revealed high expression rates of genes involved in amino acid and protein biosynthesis, while in the vegetative-growth stage, genes involved in differentiation, including the mitogen-activated protein kinase kinase similar to Kpp7 from Ustilago maydis and the orthologue to stuA from Aspergillus nidulans, were preferentially expressed. Genes involved in cell-wall synthesis were expressed during conidiogenesis. We standardized total RNA isolation from Trichoderma sp. 'atroviride type B' growing in soil and then examined the expression profiles of selected genes using qRT-PCR. The results suggested that the relative expression patterns were cyclic and not accumulative.

  3. Influence of plant root exudates, germ tube orientation and passive conidia transport on biological control of fusarium wilt by strains of nonpathogenic Fusarium oxysporum.

    PubMed

    Mandeel, Qaher A

    2006-03-01

    reached at 96 h. The presented data confirm the previous findings that attributes important for nonpathogenic fusaria to induce resistant are: rapid spore germination and orientation in response to root exudate; active root penetration and passive conidia transport in stem to initiate defence reaction without pathogenicity and enough lag period between induction and challenge inoculation. Strain C14 possesses all these qualifications and hence its ability to enhance host resistance is superior than strain C5.

  4. The Indoor Fungus Cladosporium halotolerans Survives Humidity Dynamics Markedly Better than Aspergillus niger and Penicillium rubens despite Less Growth at Lowered Steady-State Water Activity

    PubMed Central

    Segers, Frank J. J.; van Laarhoven, Karel A.; Huinink, Hendrik P.; Adan, Olaf C. G.; Wösten, Han A. B.

    2016-01-01

    ABSTRACT Indoor fungi cause damage in houses and are a potential threat to human health. Indoor fungal growth requires water, for which the terms water activity (aw) and relative humidity (RH) are used. The ability of the fungi Aspergillus niger, Cladosporium halotolerans, and Penicillium rubens at different developmental stages to survive changes in aw dynamics was studied. Fungi grown on media with high aw were transferred to a controlled environment with low RH and incubated for 1 week. Growth of all developmental stages was halted during incubation at RHs below 75%, while growth continued at 84% RH. Swollen conidia, germlings, and microcolonies of A. niger and P. rubens could not reinitiate growth when retransferred from an RH below 75% to a medium with high aw. All developmental stages of C. halotolerans showed growth after retransfer from 75% RH. Dormant conidia survived retransfer to medium with high aw in all cases. In addition, retransfer from 84% RH to medium with high aw resulted in burst hyphal tips for Aspergillus and Penicillium. Cell damage of hyphae of these fungi after incubation at 75% RH was already visible after 2 h, as observed by staining with the fluorescent dye TOTO-1. Thus, C. halotolerans is more resistant to aw dynamics than A. niger and P. rubens, despite its limited growth compared to that of these fungi at a lowered steady-state aw. The survival strategy of this phylloplane fungus in response to the dynamics of aw is discussed in relation to its morphology as studied by cryo-scanning electron microscopy (cryo-SEM). IMPORTANCE Indoor fungi cause structural and cosmetic damage in houses and are a potential threat to human health. Growth depends on water, which is available only at certain periods of the day (e.g., during cooking or showering). Knowing why fungi can or cannot survive indoors is important for finding novel ways of prevention. Until now, the ability of fungi to grow on media with little available water at steady state

  5. Aspergillus flavus Conidia-derived Carbon/Sulfur Composite as a Cathode Material for High Performance Lithium–Sulfur Battery

    NASA Astrophysics Data System (ADS)

    Xu, Maowen; Jia, Min; Mao, Cuiping; Liu, Sangui; Bao, Shujuan; Jiang, Jian; Liu, Yang; Lu, Zhisong

    2016-01-01

    A novel approach was developed to prepare porous carbon materials with an extremely high surface area of 2459.6 m2g‑1 by using Aspergillus flavus conidia as precursors. The porous carbon serves as a superior cathode material to anchor sulfur due to its uniform and tortuous morphology, enabling high capacity and good cycle lifetime in lithium sulfur-batteries. Under a current rate of 0.2 C, the carbon-sulfur composites with 56.7 wt% sulfur loading deliver an initial capacity of 1625 mAh g‑1, which is almost equal to the theoretical capacity of sulfur. The good performance may be ascribed to excellent electronic networks constructed by the high-surface-area carbon species. Moreover, the semi-closed architecture of derived carbons can effectively retard the polysulfides dissolution during charge/discharge, resulting in a capacity of 940 mAh g‑1 after 120 charge/discharge cycles.

  6. Aspergillus flavus Conidia-derived Carbon/Sulfur Composite as a Cathode Material for High Performance Lithium–Sulfur Battery

    PubMed Central

    Xu, Maowen; Jia, Min; Mao, Cuiping; Liu, Sangui; Bao, Shujuan; Jiang, Jian; Liu, Yang; Lu, Zhisong

    2016-01-01

    A novel approach was developed to prepare porous carbon materials with an extremely high surface area of 2459.6 m2g−1 by using Aspergillus flavus conidia as precursors. The porous carbon serves as a superior cathode material to anchor sulfur due to its uniform and tortuous morphology, enabling high capacity and good cycle lifetime in lithium sulfur-batteries. Under a current rate of 0.2 C, the carbon-sulfur composites with 56.7 wt% sulfur loading deliver an initial capacity of 1625 mAh g−1, which is almost equal to the theoretical capacity of sulfur. The good performance may be ascribed to excellent electronic networks constructed by the high-surface-area carbon species. Moreover, the semi-closed architecture of derived carbons can effectively retard the polysulfides dissolution during charge/discharge, resulting in a capacity of 940 mAh g−1 after 120 charge/discharge cycles. PMID:26732547

  7. Interaction with Penicillium expansum enhances Botrytis cinerea growth in grape juice medium and prevents patulin accumulation in vitro.

    PubMed

    Morales, H; Paterson, R R M; Venâncio, A; Lima, N

    2013-05-01

    Interactions between fungi occur when they grow on the same host plant. This is the case of Botrytis cinerea and Penicillium expansum on grape. P. expansum is also responsible for production of the mycotoxin patulin. In this study, the influence of the interaction between both fungi on fungal growth parameters was studied as well as the effect on the accumulation of patulin by P. expansum. For that purpose, spores of B. cinerea and P. expansum were inoculated together (mixed inoculum), and the parameters growth rate, time for growth and patulin accumulation were assessed. The presence of P. expansum conidia shortened the time for growth of mixed inoculum colonies which, at the end of incubation, were B. cinerea-like. Although some P. expansum growth was observed in mixed inoculum colonies, very low levels of patulin were observed. In assays carried out in patulin-spiked medium, B. cinerea was capable to metabolize the mycotoxin. The capabilities of B. cinerea to shorten time for growth and prevent patulin accumulation are competing abilities that facilitate grape colonization.

  8. Evaluation of Conidia-Dust Formulation of the Entomopathogenic Fungus, Metarhizium anisopliae to Biocontrol the Brown-Banded Cockroach, Supella longipalpa F.

    PubMed Central

    Sharififard, Mona; Mossadegh, Mohammad Saeed; Vazirianzadeh, Babak; Latifi, Seyed Mahmood

    2014-01-01

    Background: The brown-banded cockroach Supella longipalpa (F.) as a mechanical vector of pathogens and source of allergens has recently become widespread in the city of Ahvaz, southwestern Iran. Objectives: This research was done to evaluate the efficacy of a dust-formulation of Metarhizium anisopliae isolate IRAN 437C, as a common entomopathogenous fungus, against S. longipalpa. Materials and Methods: Conidia dust-formulations of M. anisopliae were prepared in proportions of 1%, 5%, 10%, 25%, 50% and 100% with bad wheat flour as the carrier. Cockroaches were exposed to surfaces treated with 1.5 mg/cm2 of the formulations under laboratory and semi-field conditions. Results: Cockroach mortality rates increased and survival times (ST50) decreased with an increased proportion of conidia from 1% to 100% but records taken for mortality and survival time from proportions of 25%, 50% and 100% were not significantly different. The mortality rates reached 100% and 90-100% in adults and nymphs, respectively on the seventh day. The lowest ST50 was related to the proportion of 100% (3 days). Probit analysis indicated LD50 and LD90 values of 1.7 × 106 and 1.7 × 107 conidia/cm2 for adults and these values changed to 4.5 × 106 and 2.9 × 107 for third and fourth instar nymphs at three days post exposure. Proportion of 25% caused mortality rates of 87%, 81% and 73% in adult, adult & nymph and nymph populations, respectively at four days after exposure under room conditions. Conclusions: Conidia dust-formulation of M. anospliae isolate IRAN 437C could present a promising alternative to control the brown-banded cockroach. PMID:25371804

  9. Modelling the effect of temperature, pH, water activity, and organic acids on the germination time of Penicillium camemberti and Penicillium roqueforti conidia.

    PubMed

    Kalai, Safaa; Anzala, Lexane; Bensoussan, Maurice; Dantigny, Philippe

    2017-01-02

    In this study, the influence of environmental factors on the germination time of Penicillium camemberti and Penicillium roqueforti conidia was evaluated. To do so, the effects of i/temperature, pH, water activity, and ii/organic acids were determined using models based on i/cardinal values, and ii/minimum inhibitory concentration (MIC) respectively. Cardinal values for germination of conidia were not observed to be species dependent. Minimum temperatures were estimated to be below the freezing point, with an optimum of 26.9°C, and a maximum of 33.5°C. For both species, minimal and optimal aw values were found to be 0.83 and 0.99, respectively, while for pH these values corresponded to 2.9, and 5.6. MIC values could not be determined for lactic acid because conidia of both species germinated in up to 1M concentrations, the highest concentration tested. At pH5.6, P. camemberti (MIC=0.197M) was more sensitive to propionic acid than P. roqueforti (MIC=0.796M).

  10. Repellent activity of desiccant dusts and conidia of the entomopathogenic fungus Beauveria bassiana when tested against poultry red mites (Dermanyssus gallinae) in laboratory experiments.

    PubMed

    Kilpinen, Ole; Steenberg, Tove

    2016-11-01

    Desiccant dusts and entomopathogenic fungi have previously been found to hold potential against the poultry red mite, which is an important pest in egg production and notoriously difficult to control. Both control agents may cause repellence in other arthropods and potentially also influence control levels adversely when used against the poultry red mite. Five desiccant dust products with good efficacy against the poultry red mite Dermanyssus gallinae caused avoidance behavior in mites when tested in bioassays. The repellent activity was correlated with efficacy, which was found to depend on both dose and relative humidity (RH). However, one desiccant dust was significantly less repellent compared to other dusts with similar levels of efficacy. Further, dry conidia of the fungus Beauveria bassiana were also shown to be repellent to poultry red mites, both when applied on its own and when admixed with a low dose of the desiccant dust Diamol. The pick-up of desiccant dust particles and fungus conidia from treated surfaces by mites did not differ depending on RH, whereas the overall efficacy of the two control agents were significantly higher at 75 than at 85 % RH. In addition, the combined effect of the two substances was synergistic when tested in a bioassay where mites could choose whether to cross a treated surface. This is the first time a member of Acari has been shown to be repelled by desiccant dusts and by conidia of an entomopathogenic fungus.

  11. Effect of diet on ability of Vascular Endothelial Growth Factor A (VEGFA) isoforms to alter follicular progression in bovine ovarian cortical cultures

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to determine the effect of changes in diet on ability of VEGFA isoforms to alter follicle progression in bovine ovarian cortex cultures. Our hypothesis was that diet would affect the magnitude of VEGFA isoform actions on follicular development. Heifers (n = 30) receiv...

  12. Maternal nutrition affects the ability of treatment with IGF-I and IGF-II to increase growth of the placenta and fetus, in guinea pigs.

    PubMed

    Sohlström, A; Fernberg, P; Owens, J A; Owens, P C

    2001-12-01

    The aim of this study was to investigate how administration of IGF-I and IGF-II, during early to mid pregnancy, affects maternal growth and body composition as well as fetal and placental growth, in ad libitum fed, and in moderately, chronically food restricted guinea pigs. From day 20 of gestation, mothers (3-4 months old) were infused with IGF-I, IGF-II (565 microg/day) or vehicle for 17 days and then killed on day 40 of gestation. Maternal organ weights, fetal and placental weights were assessed. Treatment with IGFs did not alter body weight gain and had small effects on body composition in the mothers. Both IGF-I and IGF-II increased fetal and placental weights in ad libitum fed dams and IGF-I increased placental weight in food restricted dams. In conclusion, treatment with IGF-I during the first half of pregnancy stimulates placental growth in both ad libitum fed and food restricted guinea pigs without affecting maternal growth while fetal growth is stimulated by IGF treatment only in ad libitum fed animals.

  13. Growth substrates and caleosin-mediated functions affect conidial virulence in the insect pathogenic fungus Beauveria bassiana.

    PubMed

    Ortiz-Urquiza, Almudena; Fan, Yanhua; Garrett, Timothy; Keyhani, Nemat O

    2016-11-01

    The entomopathogenic fungus, Beauveria bassiana, is a microbial biological control agent capable of infecting a wide range of insect hosts. Conidia (spores) initiate infection via adhesion, growth and penetration of the insect cuticle, whose outmost layer is rich in lipids. Conidial virulence was investigated in B. bassiana WT and caleosin mutants (ΔBbcal1), the latter a protein involved in lipid storage and turnover. Topical insect bioassays revealed that conidia of the WT strain showed up to 40-fold differences in LD50 values depending upon the growth substrate. The most virulent conidia were harvested from potato dextrose agar containing oleic acid, and the least potent were those derived from Sabouraud dextrose/yeast extract agar (SDAY). However, with the exception of conidia derived from SDAY and Czapek Dox agar, in which values were reduced, mean lethal times to kill (LT50) were essentially unaffected. In topical bioassays, the ΔBbcal1 mutant displayed LD50 values 5-40-fold higher than the WT depending upon the growth substrate, with ΔBbcal1 conidia derived from SDAY unable to effectively penetrate the host cuticle. The ΔBbcal1 mutant also showed concomitant dramatic increases in LT50 values from a mean of ~4.5 for WT to >8.5 days for the mutant. In contrast, intrahaemocoel injection bioassays that bypass cuticle penetration events revealed only minor effects on virulence for either WT or ΔBbcal1 conidia. These data highlight the importance of caleosin-dependent lipid mobilization and/or signalling in cuticle penetration events but suggest their dispensability for immune evasion and within-host growth.

  14. Survival of Penicillium spp. conidia during deep-frying and baking steps of frozen chicken nuggets processing.

    PubMed

    Wigmann, Évelin Francine; Moreira, Rafael Chelala; Alvarenga, Verônica Ortiz; Sant'Ana, Anderson S; Copetti, Marina Venturini

    2016-05-01

    This study aimed at determining whether Penicillium spp. strains could survive through the heat treatment applied during the processing of frozen chicken nuggets. Firstly, it was found that the conidia of Penicillium were not able to survive the heat shock in phosphate buffer at pH 7.2 in thermal death tubes (TDT) at 80 °C/30 min. Subsequently, each Penicillium strain was inoculated in frozen chicken nuggets, which were subjected to the following treatments: i) only deep frying (frying oil at 195-200 °C), ii) only baking (120-130 °C until the internal temperature reached 70 °C) and iii) deep frying followed by baking (frying oil temperature of 195-200 °C and baking temperature of 120-130 °C, until the internal temperature reached 70 °C). The results indicated that Penicillium polonicum NGT 23/12, Penicillium commune NGT 16/12, Penicillium solitum NGT 30/12 and Penicillium crustosum NGT 51/12 were able to survive after the combined treatment (deep frying followed by baking) when inoculated in chicken nuggets. P. polonicum NGT 23/12 was the most resistant strain to the combined treatment (deep frying and baking), as its population was reduced by 3 log cycles CFU/g, when the internal temperature reached 78 °C after 10 min and 30 s of baking. The present data show that if Penicillium spp. is present in high numbers in raw materials, such as breading flours, it will survive the thermal processing applied during chicken nuggets production.

  15. Effect of prior vegetative growth, inoculum density and light on conidiation in Erysiphe necator

    USDA-ARS?s Scientific Manuscript database

    A driving force in epidemics of grape powdery mildew is the abundant production of conidia. Our objective was to better define the three factors involved in the qualitative change that occurs when a mildew colony switches from vegetative growth to sporulation –inoculum density, light, and a sporulat...

  16. Zinc and Manganese Chelation by Neutrophil S100A8/A9 (Calprotectin) Limits Extracellular Aspergillus fumigatus Hyphal Growth and Corneal Infection.

    PubMed

    Clark, Heather L; Jhingran, Anupam; Sun, Yan; Vareechon, Chairut; de Jesus Carrion, Steven; Skaar, Eric P; Chazin, Walter J; Calera, José Antonio; Hohl, Tobias M; Pearlman, Eric

    2016-01-01

    Calprotectin, a heterodimer of S100A8 and S100A9, is an abundant neutrophil protein that possesses antimicrobial activity primarily because of its ability to chelate zinc and manganese. In the current study, we showed that neutrophils from calprotectin-deficient S100A9(-/-) mice have an impaired ability to inhibit Aspergillus fumigatus hyphal growth in vitro and in infected corneas in a murine model of fungal keratitis; however, the ability to inhibit hyphal growth was restored in S100A9(-/-) mice by injecting recombinant calprotectin. Furthermore, using recombinant calprotectin with mutations in either the Zn and Mn binding sites or the Mn binding site alone, we show that both zinc and manganese binding are necessary for calprotectin's antihyphal activity. In contrast to hyphae, we found no role for neutrophil calprotectin in uptake or killing of intracellular A. fumigatus conidia either in vitro or in a murine model of pulmonary aspergillosis. We also found that an A. fumigatus ∆zafA mutant, which demonstrates deficient zinc transport, exhibits impaired growth in infected corneas and following incubation with neutrophils or calprotectin in vitro as compared with wild-type. Collectively, these studies demonstrate a novel stage-specific susceptibility of A. fumigatus to zinc and manganese chelation by neutrophil-derived calprotectin.

  17. Zinc and Manganese Chelation by Neutrophil S100A8/A9 (Calprotectin) Limits Extracellular Aspergillus fumigatus Hyphal Growth and Corneal Infection

    PubMed Central

    Clark, Heather L.; Jhingran, Anupam; Sun, Yan; Vareechon, Chairut; Carrion, Steven de Jesus; Skaar, Eric P.; Chazin, Walter J.; Calera, Jose Antonio; Hohl, Tobias M.; Pearlman, Eric

    2015-01-01

    Calprotectin, a heterodimer of S100A8 and S100A9, is an abundant neutrophil protein which possesses anti-microbial activity primarily due to its ability to chelate zinc and manganese. In the current study, we showed that neutrophils from calprotectin-deficient S100A9 −/− mice have an impaired ability to inhibit Aspergillus fumigatus hyphal growth in vitro, and in infected corneas in a murine model of fungal keratitis; however, the ability to inhibit hyphal growth was restored in S100A9−/− mice by injecting recombinant calprotectin. Further, using recombinant calprotectin with mutations in either the Zn and Mn binding sites or the Mn binding site alone, we show that both zinc and manganese binding are necessary for calprotectin’s anti-hyphal activity. In contrast to hyphae, we found no role for neutrophil calprotectin in uptake or killing of intracellular A. fumigatus conidia either in vitro, or in a murine model of pulmonary aspergillosis. We also found that an A. fumigatus ΔzafA mutant, which demonstrates deficient zinc transport, exhibits impaired growth in infected corneas and following incubation with neutrophils or calprotectin in vitro as compared to wild-type. Collectively, these studies demonstrate a novel stage - specific susceptibility of A. fumigatus to zinc and manganese chelation by neutrophil-derived calprotectin. PMID:26582948

  18. The ability of exogenous growth hormone to maintain milk production during prolonged lactation in the mouse is more evident with reduced nursing frequency

    USDA-ARS?s Scientific Manuscript database

    Although growth hormone (GH) increases milk production in dairy animals, the milk production response of lactating rodents to this treatment has been variable. Milk removal frequency in the lactating mouse is about 10-fold higher than that of lactating dairy cows. The hypothesis tested in this study...

  19. Developing a General Outcome Measure of Growth in the Cognitive Abilities of Children 1 to 4 Years Old: The Early Problem-Solving Indicator

    ERIC Educational Resources Information Center

    Greenwood, Charles R.; Walker, Dale; Carta, Judith J.; Higgins, Susan K.

    2006-01-01

    Proficiency in problem solving is an important outcome in early childhood necessary for cognitive and emotional development. The development of an individual growth and development indicator of problem solving for children 1 to 4 years of age is described. Based on the general outcome measurement approach (Deno, 1997), the measure is intended for…

  20. Mycorrhizal fungi collected from the rhizospheres around different olive cultivars vary in their ability to improve growth and polyphenol levels in leeks

    USDA-ARS?s Scientific Manuscript database

    Mycorrhizal fungus spores and propagules were collected from the soils in the vicinity of roots of five different olive cultivars. These mycorrhizal fungal communities were amplified in trap cultures and then their effect on the growth and polyphenol levels of leek plants was determined. All mycorr...

  1. Growth

    NASA Astrophysics Data System (ADS)

    Waag, Andreas

    This chapter is devoted to the growth of ZnO. It starts with various techniques to grow bulk samples and presents in some detail the growth of epitaxial layers by metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and pulsed laser deposition (PLD). The last section is devoted to the growth of nanorods. Some properties of the resulting samples are also presented. If a comparison between GaN and ZnO is made, very often the huge variety of different growth techniques available to fabricate ZnO is said to be an advantage of this material system. Indeed, growth techniques range from low cost wet chemical growth at almost room temperature to high quality MOCVD growth at temperatures above 1, 000∘C. In most cases, there is a very strong tendency of c-axis oriented growth, with a much higher growth rate in c-direction as compared to other crystal directions. This often leads to columnar structures, even at relatively low temperatures. However, it is, in general, not straight forward to fabricate smooth ZnO thin films with flat surfaces. Another advantage of a potential ZnO technology is said to be the possibility to grow thin films homoepitaxially on ZnO substrates. ZnO substrates are mostly fabricated by vapor phase transport (VPT) or hydrothermal growth. These techniques are enabling high volume manufacturing at reasonable cost, at least in principle. The availability of homoepitaxial substrates should be beneficial to the development of ZnO technology and devices and is in contrast to the situation of GaN. However, even though a number of companies are developing ZnO substrates, only recently good quality substrates have been demonstrated. However, these substrates are not yet widely available. Still, the situation concerning ZnO substrates seems to be far from low-cost, high-volume production. The fabrication of dense, single crystal thin films is, in general, surprisingly difficult, even when ZnO is grown on a ZnO substrate. However

  2. Evaluation of Three Formulations of Culture Media for Isolation of Brucella spp. regarding Their Ability to Inhibit the Growth of Contaminating Organisms

    PubMed Central

    Vicente, Acácia F.; Antunes, João M. A. P.; Lara, Gustavo H. B.; Mioni, Mateus S. R.; Allendorf, Susan D.; Peres, Marina G.; Appolinário, Camila M.; Listoni, Fernando J. P.; Ribeiro, Marcio G.; Megid, Jane

    2014-01-01

    Three culture media (Brucella agar, Farrell medium, and CITA) were compared for their effectiveness in inhibiting contamination and for isolating Brucella spp. One hundred lymph nodes from pigs (n = 50) and wild boars (n = 50) with lymphadenitis were collected in slaughterhouses in the State of São Paulo and were assessed on these three selective media for Brucella spp. All of the samples were negative for Brucella spp. on the three culture media. On the agar medium, fungal (70 plates) and Gram-positive bacterial (59 plates) contaminants were observed; in the CITA medium, the absence of fungal and Gram-positive bacteria on 15 plates was observed; no bacterial or fungal growth was observed on the Farrell media. The results demonstrated that the CITA and Farrell media inhibited the growth of contaminants better than the Brucella agar. PMID:24949466

  3. Evaluation of three formulations of culture media for isolation of Brucella spp. regarding their ability to inhibit the growth of contaminating organisms.

    PubMed

    Vicente, Acácia F; Antunes, João M A P; Lara, Gustavo H B; Mioni, Mateus S R; Allendorf, Susan D; Peres, Marina G; Appolinário, Camila M; Listoni, Fernando J P; Ribeiro, Marcio G; Megid, Jane

    2014-01-01

    Three culture media (Brucella agar, Farrell medium, and CITA) were compared for their effectiveness in inhibiting contamination and for isolating Brucella spp. One hundred lymph nodes from pigs (n = 50) and wild boars (n = 50) with lymphadenitis were collected in slaughterhouses in the State of São Paulo and were assessed on these three selective media for Brucella spp. All of the samples were negative for Brucella spp. on the three culture media. On the agar medium, fungal (70 plates) and Gram-positive bacterial (59 plates) contaminants were observed; in the CITA medium, the absence of fungal and Gram-positive bacteria on 15 plates was observed; no bacterial or fungal growth was observed on the Farrell media. The results demonstrated that the CITA and Farrell media inhibited the growth of contaminants better than the Brucella agar.

  4. Allelopathic Ability of Various Aquatic Plants to Inhibit the Growth of Hydrilla verticillata (L.f.) Royle and Myriophyllum spicatum L.

    DTIC Science & Technology

    1995-06-01

    The term allelopathy was first coined by Molisch in 1937. In general, the term allelopathy refers to the detrimental effects of higher plants of one...species (the donor) on the germination, growth, or development of another species (the recipient) (Putnam 1985). Specifically, allelopathy refers to...on another through production of chemical compounds that escape into the environment. Similarly, Parker (1984) defined allelopathy as the harmful

  5. Combined ability of chromium (Cr) tolerant plant growth promoting bacteria (PGPB) and salicylic acid (SA) in attenuation of chromium stress in maize plants.

    PubMed

    Islam, Faisal; Yasmeen, Tahira; Arif, Muhammad Saleem; Riaz, Muhammad; Shahzad, Sher Muhammad; Imran, Qaiser; Ali, Irfan

    2016-11-01

    Heavy metal contamination of agricultural soil has become a serious global problem. This study was aimed to evaluate the effects of two chromium (Cr) tolerant plant growth promoting bacteria (PGPB) in combination with salicylic acid (SA) on plant growth, physiological, biochemical responses and heavy metal uptake under Cr contamination. A pot experiment (autoclaved sand as growing medium) was performed using maize (Zea mays L.) as a test crop under controlled conditions. Cr toxicity significantly reduced plant growth, photosynthetic pigment, carbohydrates metabolism and increased H2O2, MDA, relative membrane permeability, proline and Cr contents in maize leaves. However, inoculation with selected PGPB (T2Cr and CrP450) and SA application either alone or in combination alleviated the Cr toxicity and promoted plant growth by decreasing Cr accumulation, H2O2 and MDA level in maize. Furthermore, dual PGPB inoculation with SA application also improved plant performance under Cr-toxicity. Results obtained from this study indicate that PGPB inoculation and SA application enhanced Cr tolerance in maize seedlings by decreasing Cr uptake from root to shoot. Additionally, combination of both PGPB and SA also reduced oxidative stress by elevating the activities of enzymatic and non-enzymatic antioxidant, also indicated by improved carbohydrate metabolism in maize plant exposed to Cr contamination. Comparatively, alleviation effects were more pronounced in PGPB inoculated plants than SA applied plants alone. The results suggest that combined use of PGPB and SA application may be exploited for improving production potential of maize in metal (Cr) contaminated soil. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  6. A new in vitro method to detect growth and ochratoxin A-producing ability of multiple fungal species commonly found in food commodities.

    PubMed

    Abarca, M L; Bragulat, M R; Cabañes, F J

    2014-12-01

    The aim of the study was to develop a new screening method to detect growth and ochratoxin A (OTA) production by multiple fungi growing in a small quantity of culture media, using microtiter plates. Eight ochratoxigenic species were included in the study. The strains were inoculated in sterile 96-well flat-bottom microtiter plates containing Yeast Extract Sucrose broth and Czapek Yeast Extract broth and incubated at 25 °C. Growth was daily monitored by absorbance measurements for 4 days and extended to 7 and 10 days for Penicillium spp. The entire experiment was repeated twice on different days. On each sampling time, five of the seven replicate wells inoculated for each strain and culture media were randomly selected and the content of each well was removed, extracted and injected into the HPLC. No statistically significant differences were observed for absorbance and OTA values, neither between replicates nor between experiments. Quantifiable OTA levels were detected after 48 h of incubation in Aspergillus alliaceus, Aspergillus carbonarius and Aspergillus niger, after 72 h in Aspergillus flocculosus, Aspergillus steynii and Aspergillus westerdijkiae and after 7 days in Penicillium nordicum and Penicillium verrucosum. The method offers the necessary tools for a rapid detection of growth and OTA production avoiding the use of plate cultures and can be very useful when many fungal isolates need to be screened. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Detecting free radicals in biochars and determining their ability to inhibit the germination and growth of corn, wheat and rice seedlings.

    PubMed

    Liao, Shaohua; Pan, Bo; Li, Hao; Zhang, Di; Xing, Baoshan

    2014-01-01

    Biochar can benefit human society as a carbon-negative material and soil amendment. However, negative biochar impacts on plant germination and growth have been observed, and they have not been fully explained. Therefore, protocols to avoid these risks cannot be proposed. We hypothesized that the free radicals generated during charring may inhibit plant germination and growth. Significant electron paramagnetic resonance (EPR) signals were observed in the biochars derived from several types of common biomass (corn stalk, rice, and wheat straws) and the major biopolymer components of biomass (cellulose and lignin), but not in the original materials, suggesting the ubiquitous presence of free radicals in biochars. EPR signal intensity increased with increasing pyrolysis temperature, and it was dominantly contributed by oxygen centered in the mixture of oxygen- and carbon-centered free radicals as the temperature increased. The free radicals in biochars induced strong ·OH radicals in the aqueous phase. Significant germination inhibition, root and shoot growth retardation and plasma membrane damage were observed for biochars with abundant free radicals. Germination inhibition and plasma membrane damage were not obvious for biochars containing low free radicals, but they were apparent at comparable concentrations of conventional contaminants, such as heavy metals and polyaromatic hydrocarbons. The potential risk and harm of relatively persistent free radicals in biochars must be addressed to apply them safely.

  8. Rapid Isolation of the Trichoderma Strain with Higher Degrading Ability of a Filter Paper and Superior Proliferation Characteristics Using Avicel Plates and the Double-Layer Selection Medium

    NASA Astrophysics Data System (ADS)

    Toyama, Hideo; Nakano, Megumi; Satake, Yuuki; Toyama, Nobuo

    The cost of cellulase is still a problem for bioethanol production. As the cellulase of Trichoderma reesei is applicable for producing ethanol from cellulosic materials, the cellulase productivity of this fungus should be increased. Therefore, we attempted to develop a system to isolate the strain with higher degrading ability of a filter paper and superior proliferation characteristics among the conidia treated with the mitotic arrester, colchicine. When green mature conidia of T. reesei RUT C-30 were swollen, autopolyploidized, and incubated in the double-layer selection medium containing Avicel, colonies appeared on the surface earlier than the original strain. When such colonies and the original colony were incubated on the Avicel plates, strain B5, one of the colonies derived from the colchicinetreated conidia, showed superior proliferation characteristics. Moreover, when strain B5 and the original strain were compared in the filter paper degrading ability and the cellulose hydrolyzing activity, strain B5 was also superior to the original strain. It was suspected that superior proliferation characteristics of strain B5 reflects higher filter paper degrading ability. Thus, we concluded that the Trichoderma strain with higher degrading ability of a filter paper and superior proliferation characteristics can be isolated using Avicel plates and the double-layer selection medium.

  9. Growth of reading skills in children with a history of specific language impairment: the role of autistic symptomatology and language-related abilities.

    PubMed

    St Clair, Michelle C; Durkin, Kevin; Conti-Ramsden, Gina; Pickles, Andrew

    2010-03-01

    Individuals with a history of specific language impairment (SLI) often have subsequent problems with reading skills, but there have been some discrepant findings as to the developmental time course of these skills. This study investigates the developmental trajectories of reading skills over a 9-year time-span (from 7 to 16 years of age) in a large sample of individuals with a history of SLI. Relationships among reading skills, autistic symptomatology, and language-related abilities were also investigated. The results indicate that both reading accuracy and comprehension are deficient but that the development of these skills progresses in a consistently parallel fashion to what would be expected from a normative sample of same age peers. Language-related abilities were strongly associated with reading skills. Unlike individuals with SLI only, those with SLI and additional autistic symptomatology had adequate reading accuracy but did not differ from the individuals with SLI only in reading comprehension. They exhibited a significant gap between what they could read and what they could understand when reading. These findings provide strong evidence that individuals with SLI experience continued, long-term deficits in reading skills from childhood to adolescence.

  10. Evaluation of enrichment, storage, and age of blood agar medium in relation to its ability to support growth of anaerobic bacteria.

    PubMed

    Hanson, C W; Martin, W J

    1976-11-01

    By measuring the colony size of a variety of anaerobic bacteria isolated from clinical specimens, an evaluation was made of the benefits derived from the addition of several enrichments to blood agar medium commonly used for the growth of anaerobes. Similar methods were used to study the effects of various storage conditions and age of the medium. The results were compared with those obtained on freshly prepared and enriched blood agar plates as well as commercially available blood agar plates. Freshly prepared and enriched blood agar was found to give substantially larger colonies than could be grown on commercially obtained blood agar plates when both were inoculated and incubated under identical conditions. Storage of plating media under CO2 for periods of up to 72 h had only a minor effect on the growth of the anaerobic bacteria studied, but longer periods of storage under CO2 resulted in a less efficient plating medium. Nonenriched brain heart infusion (BHI) was found to be a better basal medium than Trypticase soy agar (TSA) medium. Colony size on fully enriched BHI blood agar plates was greater than nonenriched BHI greater than nonenriched TSA greater than commercially prepared nonenriched TSA plates. The data suggest that freshness of the plates may be as important as using rich media.

  11. Ablation of the ability to control the right-to-left cardiac shunt does not affect oxygen uptake, specific dynamic action or growth in the rattlesnake Crotalus durissus.

    PubMed

    Leite, Cleo A C; Taylor, Edwin W; Wang, Tobias; Abe, Augusto S; de Andrade, Denis O V

    2013-05-15

    The morphologically undivided ventricle of the heart in non-crocodilian reptiles permits the mixing of oxygen-rich blood returning from the lungs and oxygen-poor blood from the systemic circulation. A possible functional significance for this intra-cardiac shunt has been debated for almost a century. Unilateral left vagotomy rendered the single effective pulmonary artery of the South American rattlesnake, Crotalus durissus, unable to adjust the magnitude of blood flow to the lung. The higher constant perfusion of the lung circulation and the incapability of adjusting the right-left shunt in left-denervated snakes persisted over time, providing a unique model for investigation of the long-term consequences of cardiac shunting in a squamate. Oxygen uptake recorded at rest and during spontaneous and forced activity was not affected by removing control of the cardiac shunt. Furthermore, metabolic rate and energetic balance during the post-prandial metabolic increment, plus the food conversion efficiency and growth rate, were all similarly unaffected. These results show that control of cardiac shunting is not associated with a clear functional advantage in adjusting metabolic rate, effectiveness of digestion or growth rates.

  12. A 3D Culture System Enhances the Ability of Human Bone Marrow Stromal Cells to Support the Growth of Limbal Stem/Progenitor Cells

    PubMed Central

    González, Sheyla; Mei, Hua; Nakatsu, Martin N.; Baclagon, Elfren R.; Deng, Sophie X.

    2016-01-01

    The standard method of cultivating limbal epithelial progenitor/stem cells (LSCs) on a monolayer of mouse 3T3 feeder cells possesses the risk of cross-contamination in clinical applications. Human feeder cells have been used to eliminate this risk; however, efficiency from xenobiotic-free cultures on a monolayer appears to be lower than in the standard method using 3T3 cells. We investigated whether bone marrow stromal cells (BMSCs), also known as bone marrow-derived mesenchymal stem cells, could serve as feeder cells for the expansion of LSCs in the 3-dimensional (3D) system. Primary single human LSCs on a monolayer of 3T3s served as the control. Very poor growth was observed when single LSCs were cultured on BMSCs. When LSC clusters were cultured on a BMSC monolayer (CC-BM), 3D culture system (3D CC-BM) and fibrin 3D system (fibrin 3D CC-BM), the 3D CC-BM method supported a greater LSC expansion. The 3D CC-BM system produced a 2.5-fold higher cell growth rate than the control (p<0.05). The proportion of K14+ and p63αbright cells were comparable to those in the control (p>0.05), whereas the proportion of K12+ cells was lower (p<0.05). These results indicate that BMSCs can efficiently support the expansion of the LSC population in the 3D culture. PMID:26896856

  13. Structural and Topographic Dynamics of Pulmonary Histopathology and Local Cytokine Profiles in Paracoccidioides brasiliensis Conidia-Infected Mice

    PubMed Central

    Cruz, Oswaldo G.; Restrepo, Angela; Cano, Luz Elena; Lenzi, Henrique Leonel

    2011-01-01

    Background Paracoccidioidomycosis (PCM), an endemic systemic mycosis caused by the fungus Paracoccidioides brasiliensis (Pb), usually results in severe lung damage in patients. Methods and Findings Considering the difficulties to sequentially study the infection in humans, this work was done in mice inoculated intranasally with infective Pb-conidia. Lungs of control and Pb-infected mice were studied after 2-hours, 4, 8, 12 and 16-weeks post-infection (p.i) in order to define histopathologic patterns of pulmonary lesions, multiplex-cytokine profiles and their dynamics during the course of this mycosis. Besides the nodular/granulomatous lesions previously informed, results revealed additional non-formerly described lung abnormalities, such as periarterial sheath inflammation and pseudotumoral masses. The following chronologic stages occurring during the course of the experimental infection were defined: Stage one (2-hours p.i): mild septal infiltration composed by neutrophils and macrophages accompanied by an intense “cytokine burst” represented by significant increases in IL-1α, IL-1β, IL-4, IL-5, IL-6, IL-10, IL12p70, IL-13, IL-17, Eotaxin, G-CSF, MCP1, MIP1α, GM-CSF, IFN-γ, MIP1β and TNFα levels. Stage two (4-weeks p.i): presence of nodules, evidence of incipient periarterial- and intense but disperse parenchymal- inflammation, abnormalities that continued to be accompanied by hyper-secretion of those cytokines and chemokines mentioned in the first stage of infection. Stages three and four (8 and 12-weeks p.i.): fungal proliferation, inflammation and collagenesis reached their highest intensity with particular involvement of the periarterial space. Paradoxically, lung cytokines and chemokines were down-regulated with significant decreases in IL-2,IL-3,IL-5,IL-9,IL-13,IL-15,GM-CSF,IFN-γ,MIP1β and TNFα. Stage five (16-weeks p.i.): inflammation decreased becoming limited to the pseudotumoral masses and was accompanied by a “silent” cytokine response

  14. Invasiveness and anchorage independent growth ability augmented by PTEN inactivation through the PI3K/AKT/NFkB pathway in lung cancer cells.

    PubMed

    Akca, Hakan; Demiray, Aydin; Tokgun, Onur; Yokota, Jun

    2011-09-01

    PTEN is inactivated in a subset of lung cancer; therefore, we investigated the involvement of PTEN inactivation in invasiveness of lung cancer cells. AKT at Ser473 was phosphorylated in several lung cancer cell lines with loss of PTEN expression. Therefore, we created a tetracycline inducible expression system of wild-type PTEN (PTEN-WT) as well as catalytically (PTEN-G129R) and lipid phosphatase (PTEN-G129E) inactive PTEN mutants using the PC14, PC9 and PC3 lung adenocarcinoma cell lines, in which endogenous PTEN expression was not detected and AKT at Ser473 was phosphorylated by Western blot analysis. Induction of PTEN-WT reduced phosphorylation of AKT and inhibited the transcriptional activity of NFkB, whereas PTEN mutants did not, suggesting that PTEN inactivation results in the activation of the AKT/NFkB pathway in PC14, PC9 and PC3 cells. Furthermore, overexpression of PTEN-WT suppressed anchorage independent growth in soft agar and reduced invasiveness in a trans-well chamber assay of PC14 cells. Neither PTEN-G129R nor PTEN-G129E had suppressive effects on anchorage independent growth and invasiveness. Augmentation of invasiveness by constitutively active AKT was also shown in mouse NIH3T3 cells. Therefore, it was strongly indicated that activation of the PI3K/AKT/NFkB pathway by PTEN inactivation results in augmented invasiveness in lung cancer cells and lipid phosphatase activity of PTEN plays a key role in this process. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  15. Detection of Biofilms in Biopsies from Chronic Rhinosinusitis Patients: In Vitro Biofilm Forming Ability and Antimicrobial Susceptibility Testing in Biofilm Mode of Growth of Isolated Bacteria.

    PubMed

    Di Luca, Mariagrazia; Navari, Elena; Esin, Semih; Menichini, Melissa; Barnini, Simona; Trampuz, Andrej; Casani, Augusto; Batoni, Giovanna

    2017-04-08

    Chronic rhinosinusitis (CRS) is the most common illness among chronic disorders that remains poorly understood from a pathogenic standpoint and has a significant impact on patient quality of life, as well as healthcare costs. Despite being widespread, little is known about the etiology of the CRS. Recent evidence, showing the presence of biofilms within the paranasal sinuses, suggests a role for biofilm in the pathogenesis. To elucidate the role of biofilm in the pathogenesis of CRS, we assessed the presence of biofilm at the infection site and the ability of the aerobic flora isolated from CRS patients to form biofilm in vitro. For selected bacterial strains the susceptibility profiles to antibiotics in biofilm condition was also evaluated.Staphylococci represented the majority of the isolates obtained from the infection site, with S. epidermidis being the most frequently isolated species. Other isolates were represented by Enterobacteriaceae or by species present in the oral flora. Confocal laser scanning microscopy (CLSM) of the mucosal biopsies taken from patients with CRS revealed the presence of biofilm in the majority of the samples. Strains isolated from the specific infection site of the CRS patients were able to form biofilm in vitro at moderate or high levels, when tested in optimized conditions. No biofilm was observed by CLSM in the biopsies from control patients, although the same biopsies were positive for staphylococci in microbiological culture analysis. Drug-susceptibility tests demonstrated that the susceptibility profile of planktonic bacteria differs from that of sessile bacteria in biofilms.

  16. Early number knowledge and cognitive ability affect early arithmetic ability.

    PubMed

    Östergren, Rickard; Träff, Ulf

    2013-07-01

    Previous literature suggests that early number knowledge is important for the development of arithmetic calculation ability. The domain-general ability of verbal working memory also has an impact on arithmetic ability. This longitudinal study tested the impact of early number knowledge and verbal working memory on the arithmetic calculation ability of children in preschool (N=315) and then later in Grade 1 using structural equation modeling. Three models were used to test hypotheses drawn from previous literature. The current study demonstrates that both early number knowledge and the domain-general ability of verbal working memory affect preschool and Grade 1 arithmetic ability. Early number knowledge had a direct impact on the growth of arithmetic ability, whereas verbal working memory had only an indirect effect via number knowledge and preschool arithmetic ability. These results fit well with von Aster and Shalev's developmental model of numerical cognition (Developmental Medicine & Child Neurology, 2007, Vol. 49, pp. 868-873) and highlight the importance of considering arithmetic ability as independent from early number knowledge. Results also emphasize the importance of training early number knowledge before school entry to promote the development of arithmetic ability. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Blockade of Programmed Death 1 Augments the Ability of Human T Cells Engineered to Target NY-ESO-1 to Control Tumor Growth after Adoptive Transfer.

    PubMed

    Moon, Edmund K; Ranganathan, Raghuveer; Eruslanov, Evgeniy; Kim, Soyeon; Newick, Kheng; O'Brien, Shaun; Lo, Albert; Liu, Xiaojun; Zhao, Yangbing; Albelda, Steven M

    2016-01-15

    Tumor-infiltrating lymphocytes (TILs) become hypofunctional, although the mechanisms are not clear. Our goal was to generate a model of human tumor-induced TIL hypofunction to study mechanisms and to test anti-human therapeutics. We transduced human T cells with a published, optimized T-cell receptor (TCR) that is directed to a peptide within the cancer testis antigen, NY-ESO-1. After demonstrating antigen-specific in vitro activity, these cells were used to target a human lung cancer line that expressed NY-ESO-1 in the appropriate HLA context growing in immunodeficient mice. The ability of anti-PD1 antibody to augment efficacy was tested. Injection of transgenic T cells had some antitumor activity, but did not eliminate the tumors. The injected T cells became profoundly hypofunctional accompanied by upregulation of PD1, Tim3, and Lag3 with coexpression of multiple inhibitory receptors in a high percentage of cells. This model allowed us to test reagents targeted specifically to human T cells. We found that injections of an anti-PD1 antibody in combination with T cells led to decreased TIL hypofunction and augmented the efficacy of the adoptively transferred T cells. This model offers a platform for preclinical testing of adjuvant immunotherapeutics targeted to human T cells prior to transition to the bedside. Because the model employs engineering of human T cells with a TCR clone instead of a CAR, it allows for study of the biology of tumor-reactive TILs that signal through an endogenous TCR. The lessons learned from TCR-engineered TILs can thus be applied to tumor-reactive TILs. ©2015 American Association for Cancer Research.

  18. An inhibitor of the epidermal growth factor receptor function does not affect the ability of human papillomavirus 11 to form warts in the xenografted immunodeficient mouse model.

    PubMed

    Parkinson, Tanya; Howett, Mary K; Welsh, Patricia A; Patrick, Susan D; Neely, Elizabeth B; Flanagan, Neil; Pollack, Vincent A; Pustilnik, Leslie R; Moyer, Jim; Perros, Manos

    2007-04-01

    Epidermal growth factor receptor (EGFr) has been shown to be induced and activated in cells infected with HPV, suggesting that it may play a physiological role in viral replication or in the formation or maintenance of warts. To investigate this possibility, human foreskin tissue was infected with HPV11 and transplanted onto the renal capsule and the dermis of immunodeficient mice. The animals were treated orally or topically with the potent EGFr inhibitor CP-545130, with treatment starting either immediately following graft attachment, or following a 70 day period to allow development of warts. The rate of appearance of warts, wart size and number were monitored. In addition, we measured intra-lesional HPV replication levels and examined the morphology of the graft tissues. Analysis of the results showed no significant difference between placebo and compound-treated groups, despite high levels of compound present in the graft tissue. We conclude that EGFr kinase activity is not required for the development and maintenance of HPV-11-induced warts in this model.

  19. A 6-month, randomized, double-blind, placebo-controlled study evaluating the ability of a marine complex supplement to promote hair growth in men with thinning hair.

    PubMed

    Ablon, Glynis

    2016-12-01

    Male pattern baldness, or androgenetic alopecia, affects approximately 50% of the adult population and can cause poor self-image, low self-esteem and have a significant negative impact on the quality of life. An oral nutraceutical supplement based on a marine complex formulation has previously been reported to significantly increase the number of terminal hairs in women with thinning hair. The objective of this double-blind, placebo-controlled study was to confirm the beneficial effects of a similar marine complex supplement in adult male subjects with thinning hair (Viviscal(®) Man; Lifes2good, Inc., Chicago, IL, USA). Healthy adult male subjects with thinning hair associated with clinically diagnosed male pattern hair loss were enrolled and randomized to receive study drug or placebo twice daily. At Day 90, subjects indicated a significant improvement in three of six quality of life measures as well as a significant overall improvement in quality of life. After 180 days, significant increases were observed for total hair count, total hair density, and terminal hair density (for each, P = 0.001). The investigator assessments revealed significant improvements in terminal and vellus hair count and terminal hair density. Hair pull test results were significantly lower (fewer hairs removed) for study drug vs. placebo at Days 90 (P < 0.05) and 180 (P < 0.01). There were no reports of treatment-emergent adverse events. The results of this study showed for the first time that a dietary supplement containing a marine complex and other ingredients can decrease hair shedding and promote hair growth in men with thinning hair. © 2016 Wiley Periodicals, Inc.

  20. RasGAP Shields Akt from Deactivating Phosphatases in Fibroblast Growth Factor Signaling but Loses This Ability Once Cleaved by Caspase-3*

    PubMed Central

    Cailliau, Katia; Lescuyer, Arlette; Burnol, Anne-Françoise; Cuesta-Marbán, Álvaro; Widmann, Christian; Browaeys-Poly, Edith

    2015-01-01

    Fibroblast growth factor receptors (FGFRs) are involved in proliferative and differentiation physiological responses. Deregulation of FGFR-mediated signaling involving the Ras/PI3K/Akt and the Ras/Raf/ERK MAPK pathways is causally involved in the development of several cancers. The caspase-3/p120 RasGAP module is a stress sensor switch. Under mild stress conditions, RasGAP is cleaved by caspase-3 at position 455. The resulting N-terminal fragment, called fragment N, stimulates anti-death signaling. When caspase-3 activity further increases, fragment N is cleaved at position 157. This generates a fragment, called N2, that no longer protects cells. Here, we investigated in Xenopus oocytes the impact of RasGAP and its fragments on FGF1-mediated signaling during G2/M cell cycle transition. RasGAP used its N-terminal Src homology 2 domain to bind FGFR once stimulated by FGF1, and this was necessary for the recruitment of Akt to the FGFR complex. Fragment N, which did not associate with the FGFR complex, favored FGF1-induced ERK stimulation, leading to accelerated G2/M transition. In contrast, fragment N2 bound the FGFR, and this inhibited mTORC2-dependent Akt Ser-473 phosphorylation and ERK2 phosphorylation but not phosphorylation of Akt on Thr-308. This also blocked cell cycle progression. Inhibition of Akt Ser-473 phosphorylation and entry into G2/M was relieved by PHLPP phosphatase inhibition. Hence, full-length RasGAP favors Akt activity by shielding it from deactivating phosphatases. This shielding was abrogated by fragment N2. These results highlight the role played by RasGAP in FGFR signaling and how graded stress intensities, by generating different RasGAP fragments, can positively or negatively impact this signaling. PMID:26109071

  1. Cell density governs the ability of human bronchial epithelial cells to recognize serum and transforming growth factor beta-1 as squamous differentiation-inducing agents.

    PubMed Central

    Ke, Y.; Gerwin, B. I.; Ruskie, S. E.; Pfeifer, A. M.; Harris, C. C.; Lechner, J. F.

    1990-01-01

    Sparse (75 to 2000 cells/cm2) density cultures of normal human bronchial epithelial cells uniformly undergo terminal squamous differentiation when incubated in medium containing serum (fetal bovine serum [FBS]) or transforming growth factor beta-1 (TGF-beta 1). It was found that the cell density of the culture affects the probability that a cell will respond to these differentiation-inducing agents. Thus whereas irreversible inhibition of DNA synthesis occurs in sparse cell-density cultures within 24 hours after exposure, only a transient (less than 36 hours) depression in DNA synthesis was seen in high (more than 10,000 cells/cm2) density cultures. In addition, although phase microscopic image analysis revealed that virtually all of the cells displayed a squamous morphology within 1 hour after exposure to FBS or TGF-beta 1, observations made 48 to 72 hours later showed the presence of clusters of small prolate spheroid-shaped cells surrounded by many involucrin-positive squamous-appearing cells. Only the small cells were capable of DNA synthesis and cell division as determined by autoradiography and time-lapse photomicrographic images. These replicating cells immediately undergo squamous differentiation if they are subcultured and reinoculated at low cell density and incubated in medium supplemented with FBS or TGF-beta 1. Therefore the probability that a human bronchial epithelial cell will be refractive to FBS- or TGF-beta 1 induced terminal squamous differentiation is solely a function of the cell density of the culture. Images Figure 7 Figure 8 Figure 9 PMID:2221015

  2. Identification of a gene product induced by hard-surface contact of Colletotrichum gloeosporioides conidia as a ubiquitin-conjugating enzyme by yeast complementation.

    PubMed

    Liu, Z M; Kolattukudy, P E

    1998-07-01

    The germinating conidia of many phytopathogenic fungi on hosts must differentiate into an infection structure called the appressorium in order to penetrate their hosts. Chemical signals, such as the host's surface wax or fruit ripening hormone, ethylene, trigger germination and appressorium formation of the avocado pathogen Colletotrichum gloeosporioides only after the conidia are in contact with a hard surface. What role this contact plays is unknown. Here, we describe isolation of genes expressed during the early stage of hard-surface treatment by a differential-display method and report characterization of one of these cloned genes, chip1 (Colletotrichum hard-surface induced protein 1 gene), which encodes a ubiquitin-conjugating enzyme. RNA blots clearly showed that it is induced by hard-surface contact and that ethylene treatment enhanced this induction. The predicted open reading frame (ubc1Cg) would encode a 16.2-kDa ubiquitin-conjugating enzyme, which shows 82% identity to the Saccharomyces cerevisiae UBC4-UBC5 E2 enzyme, comprising a major part of total ubiquitin-conjugating activity in stressed yeast cells. UBC1Cg can complement the proteolysis deficiency of the S. cerevisiae ubc4 ubc5 mutant, indicating that ubiquitin-dependent protein degradation is involved in conidial germination and appressorial differentiation.

  3. Environmental Scanning Electron Microscopy characterization of the adhesion of conidia from Penicillium expansum to cedar wood substrata at different pH values.

    PubMed

    El Abed, Soumya; Ibnsouda, Saad Koraichi; Latrache, Hassan; Meftah, Hasna; Tahri, Nezha Joutey; Hamadi, Fatima

    2012-04-01

    Initial microbial adhesion to surfaces is a complicated process that is affected by a number of factors. An important property of a solution that may influence adhesion is pH. The surface properties of the cedar wood were characterized by the sessile drop technique. Moreover, the interfacial free energy of surface adhesion to the cedar wood was determined under pH values (2, 3, 5, 7, 9 and 11). The results showed that cedar wood examined at different pH levels could be considered hydrophobic ranged from Giwi = -13.1 mJ/m(2) to Giwi = -75 mJ/m(2). We noted that the electron-donor character of cedar wood was important at both basic and limit acidic conditions (pH 11 and pH 3) and it decreased at intermediate pH (pH 5). The cedar wood substratum presents a weak electron acceptor under various pH's. In addition, the adhesion of conidia from Penicilllium expansum to the cedar wood surfaces at different pH values (2, 3, 5, 7, 9 and 11) was investigated using Environmental Scanning Electron Microscopy and image analysis was assessed with the Mathlab(®) program. The data analysis showed that the conidia from P. expansum were strongly influenced by the pH. The maximum adhesion occurs in the pH 11 and pH 3 and decreased to 24% at pH 5.

  4. Combination of driselase and lysing enzyme in one molar potassium chloride is effective for the production of protoplasts from germinated conidia of Fusarium verticillioides.

    PubMed

    Ramamoorthy, Vellaisamy; Govindaraj, Lavanya; Dhanasekaran, Madhumitha; Vetrivel, Sharmilee; Kumar, Krish K; Ebenezar, Edward

    2015-04-01

    Various cell wall degrading enzymes and the protoplasting media were evaluated for the production of protoplast in Fusarium verticillioides. Among the various enzymes tested, driselase at 12.5 mg/ml in 1 M KCl protoplasting medium produced the maximum number of protoplast. Next to driselase, lysing enzyme at 10 mg/ml in 1.2 M MgSO4 protoplasting medium was found to be the second best enzyme for the production of protoplast. More interestingly, the combined use of driselase @ 12.5 mg/ml and lysing enzyme @ 10 mg/ml in 1 M KCl exhibited the additive effect on protoplast formation. Germinated conidia of F. verticillioides are the most susceptible fungal material for protoplast production. The use of sucrose at 1.2 M in the regeneration medium supported the maximum regeneration of protoplast. From the present study, we recommend driselase (12.5 mg/ml) and lysing enzyme (10 mg/ml) in 1 M KCl protoplasting medium and germinated conidia of F. verticillioides for the maximum production of protoplasts and 1.2 M sucrose is the best osmoticum for the regeneration of protoplasts. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Phosphorylation of the adaptor protein SH2B1β regulates its ability to enhance growth hormone-dependent macrophage motility.

    PubMed

    Su, Hsiao-Wen; Lanning, Nathan J; Morris, David L; Argetsinger, Lawrence S; Lumeng, Carey N; Carter-Su, Christin

    2013-04-15

    Previous studies have shown that growth hormone (GH) recruits the adapter protein SH2B1β to the GH-activated, GH receptor-associated tyrosine kinase JAK2, implicating SH2B1β in GH-dependent actin cytoskeleton remodeling, and suggesting that phosphorylation at serines 161 and 165 in SH2B1β releases SH2B1β from the plasma membrane. Here, we examined the role of SH2B1β in GH regulation of macrophage migration. We show that GH stimulates migration of cultured RAW264.7 macrophages, and primary cultures of peritoneal and bone marrow-derived macrophages. SH2B1β overexpression enhances, whereas SH2B1 knockdown inhibits, GH-dependent motility of RAW macrophages. At least two independent mechanisms regulate the SH2B1β-mediated changes in motility. In response to GH, tyrosines 439 and 494 in SH2B1β are phosphorylated. Mutating these tyrosines in SH2B1β decreases both basal and GH-stimulated macrophage migration. In addition, mutating the polybasic nuclear localization sequence (NLS) in SH2B1β or creating the phosphomimetics SH2B1β(S161E) or SH2B1β(S165E), all of which release SH2B1β from the plasma membrane, enhances macrophage motility. Conversely, SH2B1β(S161/165A) exhibits increased localization at the plasma membrane and decreased macrophage migration. Mutating the NLS or the nearby serine residues does not alter GH-dependent phosphorylation on tyrosines 439 and 494 in SH2B1β. Mutating tyrosines 439 and 494 does not affect localization of SH2B1β at the plasma membrane or movement of SH2B1β into focal adhesions. Taken together, these results suggest that SH2B1β enhances GH-stimulated macrophage motility via mechanisms involving phosphorylation of SH2B1β on tyrosines 439 and 494 and movement of SH2B1β out of the plasma membrane (e.g. as a result of phosphorylation of serines 161 and 165).

  6. A 3-Month, Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Ability of an Extra-Strength Marine Protein Supplement to Promote Hair Growth and Decrease Shedding in Women with Self-Perceived Thinning Hair

    PubMed Central

    Ablon, Glynis

    2015-01-01

    An oral marine protein supplement (MPS) is designed to promote hair growth in women with temporary thinning hair (Viviscal Extra Strength; Lifes2good, Inc., Chicago, IL). This double-blind, placebo-controlled study assessed the ability of MPS to promote terminal hair growth in adult women with self-perceived thinning hair associated with poor diet, stress, hormonal influences, or abnormal menstrual cycles. Adult women with thinning hair were randomized to receive MPS (N = 30) or placebo (N = 30) twice daily for 90 days. Digital images were obtained from a 4 cm2 area scalp target area. Each subject's hair was washed and shed hairs were collected and counted. After 90 days, these measures were repeated and subjects completed Quality of Life and Self-Assessment Questionnaires. MPS-treated subjects achieved a significant increase in the number of terminal hairs within the target area (P < 0.0001) which was significantly greater than placebo (P < 0.0001). MPS use also resulted in significantly less hair shedding (P = 0.002) and higher total Self-Assessment (P = 0.006) and Quality of Life Questionnaires scores (P = 0.035). There were no reported adverse events. MPS promotes hair growth and decreases hair loss in women suffering from temporary thinning hair. This trial is registered with ClinicalTrials.gov Identifier: NCT02297360. PMID:25883641

  7. Effect of different photoperiods on the growth, infectivity and colonization of Trinidadian strains of Paecilomyces fumosoroseus on the greenhouse whitefly, Trialeurodes vaporariorum, using a glass slide bioassay.

    PubMed

    Avery, Pasco B; Faull, Jane; Simmonds, Monique S J

    2004-01-01

    Growth, infectivity and colonization rates for blastospores and conidia of Trinidadian strains T, T10, and T11 of Paecilomyces fumosoroseus (Wize) Brown and Smith were assessed for activity against late fourth-instar nymphs of Trialeurodes vaporariorum (Westwood) (Homoptera:Aleyrodidae) under two different photoperiods (24 and 16 hour photophase). A glass-slide bioassay and a fungal development index, modified for both blastospores and conidia, were used to compare the development rates of the fungal strains on the insect hosts. Fewer adult whiteflies emerged from nymphs treated with blastospores and reared under a 16:8 hour light:dark photoperiod than a 24:0 hour photoperiod. Eclosion times of whitefly adults that emerged from nymphs treated with the different strains of conidia were similar over the 8 day experimental period at both light regimes. The percent eclosion of adult whiteflies seems to be directly correlated with the speed of infection of the blastospore or conidial treatment and the photoperiod regime. The longer photophase had a significant positive effect on development index for blastospores; however, a lesser effect was observed for the conidia at either light regime. Blastospore strain T11 offered the most potential of the three Trinidadian strains against T. vaporariorum fourth-instar nymphs, especially under constant light. The glass-slide bioassay was successfully used to compare both blastospores and conidia of P. fumosoroseus. It can be used to determine the pathogenicity and the efficacy of various fungal preparations against aleyrodid pests.

  8. Inhibition of spoilage mould conidia by acetic acid and sorbic acid involves different modes of action, requiring modification of the classical weak-acid theory.

    PubMed

    Stratford, Malcolm; Plumridge, Andrew; Nebe-von-Caron, Gerhardt; Archer, David B

    2009-11-30

    Fungal spoilage of many foods is prevented by weak-acid preservatives such as sorbic acid or acetic acid. We show that sorbic and acetic acids do not both inhibit cells by lowering of internal pH alone and that the "classical weak-acid theory" must be revised. The "classical weak-acid theory" suggests that all lipophilic acids with identical pK(a) values are equally effective as preservatives, causing inhibition by diffusion of molecular acids into the cell, dissociation, and subsequent acidification of the cytoplasm. Using a number of spoilage fungi from different genera, we have shown that sorbic acid was far more toxic than acetic acid, and no correlation existed between resistance to acetic acid and resistance to sorbic acid. The molar ratio of minimum inhibitory concentrations (MICs) (acetic: sorbic) was 58 for Paecilomyces variotii and 14 for Aspergillus phoenicis. Using flow cytometry on germinating conidia of Aspergillusniger, acetic acid at pH 4.0 caused an immediate decline in the mean cytoplasmic pH (pH(i)) falling from neutrality to approximately pH 4.7 at the MIC (80 mM). Sorbic acid also caused a rapid but far smaller drop in pH(i), at the MIC (4.5 mM); the pH remained above pH 6.3. Over 0-5 mM, a number of other weak acids caused a similar fall in cytoplasmic pH. It was concluded that while acetic acid inhibition of A. niger conidia was due to cytoplasmic acidification, inhibition by sorbic acid was not. A possible membrane-mediated mode of action of sorbic acid is discussed.

  9. Conceptions of Ability.

    ERIC Educational Resources Information Center

    Jagacinski, Carolyn M.; Nicholls, John G.

    Two different conceptions of ability are proposed. The first conception of ability is more differentiated and generally employed by adults and older children. Here ability level is defined with reference to the performance of others assuming that optimum effort was employed. High ability means higher than others. The second conception of ability…

  10. Prostaglandin E2 promotes the cell growth and invasive ability of hepatocellular carcinoma cells by upregulating c-Myc expression via EP4 receptor and the PKA signaling pathway.

    PubMed

    Xia, Shukai; Ma, Juan; Bai, Xiaoming; Zhang, Hai; Cheng, Shanyu; Zhang, Min; Zhang, Li; Du, Mingzhan; Wang, Yipin; Li, Hai; Rong, Rong; Shi, Feng; Yang, Qinyi; Leng, Jing

    2014-10-01

    Hepatocellular carcinoma (HCC) represents a major health problem worldwide. Prostaglandin E2 (PGE2), the predominant product of cyclooxygenase-2, has been implicated in hepatocarcinogenesis. However, the underlying molecular mechanisms remain to be further elucidated. c-myc, a cellular proto-oncogene, is activated or overexpressed in many types of human cancer, including HCC. The present study was designed to investigate the internal relationship and molecular mechanisms between PGE2 and c-Myc in HCC, and to define its role in HCC cell growth and invasion. Our results showed that PGE2 significantly upregulated c-Myc expression at both the mRNA and protein levels, and knockdown of c-Myc blocked PGE2-induced HCC cell growth and invasive ability in human HCC Huh-7 cells. The effect of PGE2 on c-Myc expression was mainly through the EP4 receptor, and EP4 receptor-mediated c-Myc protein upregulation largely depended on de novo biosynthesis of c-Myc mRNA and its protein. EP4 receptor signaling activated GS/AC and increased the intracellular cAMP level in Huh-7 cells. The adenylate cyclase (AC) activator forskolin mimicked the effects of the EP4 receptor agonist on c-Myc expression, while the AC inhibitor SQ22536 reduced EP4 receptor-mediated c-Myc upregulation. These data confirm the involvement of the GS/AC/cAMP pathway in EP4 receptor-mediated c-Myc upregulation. Moreover, the phosphorylation levels of CREB protein were markedly elevated by EP4 receptor signaling, and by using specific inhibitor and siRNA interference, we demonstrated that PKA/CREB was also involved in the EP4 receptor-mediated c-Myc upregulation. In summary, the present study revealed that PGE2 significantly upregulates c-Myc expression at both mRNA and protein levels through the EP4R/GS/AC/cAMP/PKA/CREB signaling pathway, thus promoting cell growth and invasion in HCC cells. Targeting of the PGE2/EP4R/c-Myc pathway may be a new therapeutic strategy to prevent and cure human HCC.

  11. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    NASA Technical Reports Server (NTRS)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  12. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    NASA Technical Reports Server (NTRS)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  13. Morphogenetic Circuitry Regulating Growth and Development in the Dimorphic Pathogen Penicillium marneffei

    PubMed Central

    Boyce, Kylie J.

    2013-01-01

    Penicillium marneffei is an emerging human-pathogenic fungus endemic to Southeast Asia. Like a number of other fungal pathogens, P. marneffei exhibits temperature-dependent dimorphic growth and grows in two distinct cellular morphologies, hyphae at 25°C and yeast cells at 37°C. Hyphae can differentiate to produce the infectious agents, asexual spores (conidia), which are inhaled into the host lung, where they are phagocytosed by pulmonary alveolar macrophages. Within macrophages, conidia germinate into unicellular yeast cells, which divide by fission. This minireview focuses on the current understanding of the genes required for the morphogenetic control of conidial germination, hyphal growth, asexual development, and yeast morphogenesis in P. marneffei. PMID:23204189

  14. Morphogenetic circuitry regulating growth and development in the dimorphic pathogen Penicillium marneffei.

    PubMed

    Boyce, Kylie J; Andrianopoulos, Alex

    2013-02-01

    Penicillium marneffei is an emerging human-pathogenic fungus endemic to Southeast Asia. Like a number of other fungal pathogens, P. marneffei exhibits temperature-dependent dimorphic growth and grows in two distinct cellular morphologies, hyphae at 25°C and yeast cells at 37°C. Hyphae can differentiate to produce the infectious agents, asexual spores (conidia), which are inhaled into the host lung, where they are phagocytosed by pulmonary alveolar macrophages. Within macrophages, conidia germinate into unicellular yeast cells, which divide by fission. This minireview focuses on the current understanding of the genes required for the morphogenetic control of conidial germination, hyphal growth, asexual development, and yeast morphogenesis in P. marneffei.

  15. Indictment of Ability Grouping

    ERIC Educational Resources Information Center

    Tuckman, Bruce

    1972-01-01

    The use of ability grouping restricts students to interact with others who have been identified as similar in ability and carries with it the stigma of failure and the operation of the self-fulfilling prophecy. (Author)

  16. Ability of Slovakian Pupils to Identify Birds

    ERIC Educational Resources Information Center

    Prokop, Pavol; Rodak, Rastislav

    2009-01-01

    A pupil's ability to identify common organisms is necessary for acquiring further knowledge of biology. We investigated how pupils were able to identify 25 bird species following their song, growth habits, or both features presented simultaneously. Just about 19% of birds were successfully identified by song, about 39% by growth habit, and 45% of…

  17. Ability of Slovakian Pupils to Identify Birds

    ERIC Educational Resources Information Center

    Prokop, Pavol; Rodak, Rastislav

    2009-01-01

    A pupil's ability to identify common organisms is necessary for acquiring further knowledge of biology. We investigated how pupils were able to identify 25 bird species following their song, growth habits, or both features presented simultaneously. Just about 19% of birds were successfully identified by song, about 39% by growth habit, and 45% of…

  18. Role of ozone in UV-C disinfection, demonstrated by comparison between wild-type and mutant conidia of Aspergillus niger.

    PubMed

    Liu, Jing; Zhou, Lin; Chen, Ji-Hong; Mao, Wang; Li, Wen-Jian; Hu, Wei; Wang, Shu-Yang; Wang, Chun-Ming

    2014-01-01

    This study aimed to investigate the tolerance of a melanized wild-type strain of Aspergillus niger (CON1) and its light-colored mutant (MUT1) to UV-C light and the concomitantly generated ozone. Treatments were segregated into four groups based on whether UV irradiation was used and the presence or absence of ozone: (-UV, -O3), (-UV, +O3), (+UV, -O3) and (+UV, +O3). The survival of CON1 and MUT1 conidia under +UV decreased as the exposure time increased, with CON1 showing greater resistance to UV irradiation than MUT1. Ozone induced CON1 conidium inactivation only under conditions of UV radiation exposure. While, the inactivation effect of ozone on MUT1 was always detectable regardless of the presence of UV irradiation. Furthermore, the CON1 conidial suspension showed lower UV light transmission than MUT1 when examined at the same concentration. Compared with the pigment in MUT1, the melanin in CON1 exhibited more potent radical-scavenging activity and stronger UV absorbance. These results suggested that melanin protected A. niger against UV disinfection via UV screening and free radical scavenging. The process by which UV-C disinfection induces a continual decrease in conidial survival suggests that UV irradiation and ozone exert a synergistic fungicidal effect on A. niger prior to reaching a plateau.

  19. Pathogenicity of conidia-based preparations of entomopathogenic fungi against the greenhouse pest aphids Myzus persicae, Aphis gossypii, and Aulacorthum solani (Hemiptera: Aphididae).

    PubMed

    Jandricic, S E; Filotas, M; Sanderson, J P; Wraight, S P

    2014-05-01

    Seeking new isolates of entomopathogenic fungi with greater virulence against greenhouse aphid pests than those currently registered in North America for control of these insects, single-dose screening assays of 44 selected fungal isolates and 4 commercially available strains were conducted against first-instar nymphs of Myzus persicae and Aphis gossypii. The assays identified a number of Beauveria and Metarhizium isolates with virulence equal to or greater than that of the commercial strains against the nymphal aphids, but none exhibited exceptionally high virulence. Virulence of Isaria isolates was unexpectedly low (<31% mortality at doses>1000conidia/mm(2)). In dose-response assays, Beauveria ARSEF 5493 proved most virulent against M. persicae and A. gossypii; however, LC50s of this isolate did not differ significantly from those of B. bassiana commercial strain JW-1. Dose-response assays were also conducted with Aulacorthum solani, the first reported evaluations of Beauveria and Metarhizium against this pest. The novel isolate Metarhizium 5471 showed virulence⩾that of Beauveria 5493 in terms of LC25 and LC50, but 5493 produced a steeper dose response (slope). Additional tests showed that adult aphids are more susceptible than nymphs to fungal infection but confirmed that infection has a limited pre-mortem effect on aphid reproduction. Effects of assay techniques and the potential of fungal pathogens as aphid-control agents are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Visual expression analysis of the responses of the alternative oxidase gene (aox1) to heat shock, oxidative, and osmotic stresses in conidia of citric acid-producing Aspergillus niger.

    PubMed

    Honda, Yuki; Hattori, Takasumi; Kirimura, Kohtaro

    2012-03-01

    The citric acid-producing filamentous fungus Aspergillus niger WU-2223L shows cyanide-insensitive respiration catalyzed by alternative oxidase in addition to the cytochrome pathway. Sequence analysis of the 5' flanking region of the alternative oxidase gene (aox1) revealed a potential heat shock element (HSE) and a stress response element (STRE). We have previously confirmed aox1 expression in conidia. In this study, to confirm whether the upstream region of aox1 responds to various stresses, we used a visual expression analysis system for single-cell conidia of the A. niger strain AOXEGFP-1. This strain harbored a fusion gene comprising aox1 and egfp, which encodes the enhanced green fluorescent protein (EGFP). The fluorescence intensity of EGFP increased in conidia of A. niger AOXEGFP-1 that were subjected to heat shock at 35-45 °C, oxidative stress by exposure to 5mM paraquat or 1 mM t-butylhydroperoxide, or osmotic stresses by exposure to 0.5 M KCl or 1.0 M mannitol. These results indicate that the putative HSE and STRE in the upstream region of aox1 directly or indirectly respond to heat shock, oxidative, and osmotic stresses.

  1. Effect of a heterotrimeric G protein alpha subunit on conidia germination, stress response, and roquefortine C production in Penicillium roqueforti.

    PubMed

    García-Rico, Ramón O; Chávez, Renato; Fierro, Francisco; Martín, Juan F

    2009-06-01

    Heterotrimeric G protein signaling regulates many processes in fungi, such as development, pathogenicity, and secondary metabolite biosynthesis. For example, the Galpha subunit Pga1 from Penicillium chrysogenum regulates conidiation and secondary metabolite production in this fungus. The dominant activating allele, pga1G42R, encoding a constitutively active Pga1 Galpha subunit, was introduced in Penicillium roqueforti by transformation, resulting in a phenotype characterized by low sporulation and slow growth. In this work, the effect of the constitutively active Pga1G42R Galpha subunit on conidial germination, stress tolerance, and roquefortine C production of P. roqueforti was studied. Pga1G42R triggered germination in the absence of a carbon source, in addition to negatively regulating thermal and osmotic stress tolerance. The presence of the Pga1G42R Galpha subunit also had an important effect on roquefortine C biosynthesis, increasing production and maintaining high levels of the mycotoxin throughout a culture period of 30 days. Together, the results suggest that G protein-mediated signaling participates in the regulation of these three processes in P. roqueforti.

  2. Apollo MEED mycology revisited and reviewed, including the Trichophyton terrestre keratinophilic growth at splashdown and 23 years after exposure to space parameters.

    PubMed

    Volz, P A; Long, J D; Veselenak, J M

    1995-01-01

    Keratinophilic Trichophyton terrestre conidia were exposed to selected parameters of space flight including 254, 280 and 300 nm UV light, full light and total darkness of space. Phenotypic isolates were grown on human hair collected from one source at years 1 and 23 after splashdown. The patterns of fungal growth on the hair, and the hair deterioration rates, were noted according to the space exposure. Growth and deterioration were consistent but slightly reduced at year 23.

  3. Fairness and Ability Grouping.

    ERIC Educational Resources Information Center

    Strike, Kenneth A.

    1983-01-01

    A recent controversy regarding ability grouping is that it is often perceived as a means whereby racial or class bias can be subtly transformed into mechanisms of discrimination which exhibit the appearance of fairness and objectivity. This article addresses the question of fairness in ability grouping. (CJB)

  4. Effects of volatile organic compounds from Streptomyces albulus NJZJSA2 on growth of two fungal pathogens.

    PubMed

    Wu, Yuncheng; Yuan, Jun; E, Yaoyao; Raza, Waseem; Shen, Qirong; Huang, Qiwei

    2015-09-01

    A Streptomyces albulus strain NJZJSA2 was isolated from the forest soil sample of Tzu-chin Mountain (Nanjing China) and identified based on its morphological and physiological properties and 16S rDNA gene sequence analysis. The strain S. albulus NJZJSA2 was evaluated for the production of antifungal volatile organic compounds (VOCs) against two fungal pathogens. Results showed that the VOCs generated by S. albulus NJZJSA2 inhibited mycelial growth of Sclerotinia sclerotiorum (SS) and Fusarium oxysporum (FO) by 100 and 56.3%, respectively. The germination of SS sclerotia and FO conidia was completely inhibited in the presence of VOCs produced by S. albulus NJZJSA2 in vitro. In soil, the VOCs delayed the germination of SS sclerotia and inhibited the germination of FO conidia for 45 days. The strain S. albulus NJZJSA2 was able to produce 13 VOCs based on GC/MS analyses. Among those, six compounds were purchased and used for the antifungal activity assay. Three relatively abundant VOCs, 4-methoxystyrene, 2-pentylfuran, and anisole were proved to have antifungal activity. Microscopy analysis showed that the pathogen hyphae were shriveled and damaged after treatment with 4-methoxystyrene. These results suggest that the S. albulus strain NJZJSA2 produce VOCs that not only reduce the growth of SS and FO, but also significantly inhibit the SS sclerotia and FO conidia. The results are useful for the better understanding of biocontrol mechanisms by S. albulus strains and will help to improve the biological control efficiency of lethal plant diseases.

  5. Susceptibility of larvae of Galleria mellonella to infection by Aspergillus fumigatus is dependent upon stage of conidial germination.

    PubMed

    Renwick, Julie; Daly, Paul; Reeves, Emer P; Kavanagh, Kevin

    2006-06-01

    The ability of conidia of the human pathogenic fungus Aspergillus fumigatus to kill larvae of the insect Galleria mellonella was investigated. Conidia at different stages of the germination process displayed variations in their virulence as measured using the Galleria infection model. Non-germinating ('resting') conidia were avirulent except when an inoculation density of 1 x 10(7) conidia per insect was used. Conidia that had been induced to commence the germination process by pre-culturing in growth medium for 3 h were capable of killing larvae at densities of 1 x 10(6) and 1 x 10(7) per insect. An inoculation density of 1 x 10(5) conidia per insect remained avirulent. Conidia in the outgrowth phase of germination (characterised as the formation of a germ tube) were the most virulent and were capable of killing 100% of larvae after 5 or 24 h when 1 x 10(7) or 1 x 10(6) conidia, that had been allowed to germinate for 24 h, were used. Examination of the response of insect haemocytes to conidia at different stages of the germination process established that haemocytes could engulf non-germinating conidia and those in the early stages of the germination process but that conidia, which had reached the outgrowth stages of germination were not phagocytosed. The results presented here indicate that haemocytes of G. mellonella are capable of phagocytosing A. fumigatus conidia less than 3.0 microm in diameter but that conidia greater than this are too large to be engulfed. The virulence of A. fumigatus in G. mellonella larvae can be ascertained within 60-90 h if infection densities of 1 x 10(6) or 1 x 10(7) activated conidia (pre-incubated for 2-3 h) per insect are employed.

  6. Measuring creative imagery abilities

    PubMed Central

    Jankowska, Dorota M.; Karwowski, Maciej

    2015-01-01

    Over the decades, creativity and imagination research developed in parallel, but they surprisingly rarely intersected. This paper introduces a new theoretical model of creative visual imagination, which bridges creativity and imagination research, as well as presents a new psychometric instrument, called the Test of Creative Imagery Abilities (TCIA), developed to measure creative imagery abilities understood in accordance with this model. Creative imagination is understood as constituted by three interrelated components: vividness (the ability to create images characterized by a high level of complexity and detail), originality (the ability to produce unique imagery), and transformativeness (the ability to control imagery). TCIA enables valid and reliable measurement of these three groups of abilities, yielding the general score of imagery abilities and at the same time making profile analysis possible. We present the results of nine studies on a total sample of more than 1700 participants, showing the factor structure of TCIA using confirmatory factor analysis, as well as provide data confirming this instrument's validity and reliability. The availability of TCIA for interested researchers may result in new insights and possibilities of integrating the fields of creativity and imagination science. PMID:26539140

  7. Measuring creative imagery abilities.

    PubMed

    Jankowska, Dorota M; Karwowski, Maciej

    2015-01-01

    Over the decades, creativity and imagination research developed in parallel, but they surprisingly rarely intersected. This paper introduces a new theoretical model of creative visual imagination, which bridges creativity and imagination research, as well as presents a new psychometric instrument, called the Test of Creative Imagery Abilities (TCIA), developed to measure creative imagery abilities understood in accordance with this model. Creative imagination is understood as constituted by three interrelated components: vividness (the ability to create images characterized by a high level of complexity and detail), originality (the ability to produce unique imagery), and transformativeness (the ability to control imagery). TCIA enables valid and reliable measurement of these three groups of abilities, yielding the general score of imagery abilities and at the same time making profile analysis possible. We present the results of nine studies on a total sample of more than 1700 participants, showing the factor structure of TCIA using confirmatory factor analysis, as well as provide data confirming this instrument's validity and reliability. The availability of TCIA for interested researchers may result in new insights and possibilities of integrating the fields of creativity and imagination science.

  8. Girls underestimate maths ability

    NASA Astrophysics Data System (ADS)

    2017-05-01

    A study by psychologists in the US has found that high-school girls rate their competence in mathematics lower than boys, even for those with similar abilities (Front. Psychol. 10.3389/fpsyg.2017.00386).

  9. AgrAbility Project

    MedlinePlus

    ... About AgrAbility State Projects Directory The Toolbox AT Database Resources Veterans & Beginning Farmers Communities of Interest News ... 800) 825-4264 Home About The Toolbox AT Database Resources Online Training Contact Us You are here: ...

  10. The role of diamondback moth cuticle surface compounds in pre-penetration growth of the entomopathogen Isaria fumosoroseus.

    PubMed

    Ali, Shaukat; Huang, Zhen; Ren, Shunxiang

    2010-10-01

    Transcript patterns elicited in response to hosts can reveal how fungi recognize suitable hosts and the mechanisms involved in pathogenicity. These patterns could be fashioned by recognition of host-specific topographical features or by chemical components displayed or released by the host. We investigated this in three isolates of Isaria fumosoroseus which has shown considerable pathogenic ability against Plutella xylostella. Conidia inoculated to hind wings had the highest germination ability while the conidia inoculated to head regions showed the lowest germination. Conidia applied to diamondback moth wings showed slightly lower rates of germination than those incubated on SDA. Although I. funosoroseus isolates germinated well on crude methanol extracts, only low levels of germination occurred on hexane and dichloromethane extracts. Similarly, poor germination was also observed on diamondback moth hind wing from which cuticular lipids were extracted by using methanol when compared to the untreated hind wings showing that simple polar compounds are required to stimulate germination before the fungus can make effective use of a complex mixture of non-polar lipids. Such studies could address the origin of intraspecies differences and correlate these differences with the underlying metabolic and biosynthetic differences that define different host ranges.

  11. Microcycle Conidiation in Cercospora zeae-maydis.

    PubMed

    Lapaire, Carrie L; Dunkle, Larry D

    2003-02-01

    ABSTRACT Conidia of Cercospora zeae-maydis are the primary inoculum causing gray leaf spot of maize. On nutrient-deficient substrates, but not on water on the leaf surface, conidia germinate and develop secondary conidia on conidiophores produced from germ tubes or conidial cells. A population of conidia increases its numbers more than twofold by 2 days on the surface of a water droplet and by fourfold on trichomes. This microcycle conidiation is suppressed by hydrogen peroxide and ammonium compounds but not by nitrate compounds, amino acids, or simple sugars. Microcycle conidiation is sensitive to alpha-amanitin and cycloheximide, suggesting that new RNA and proteins must be synthesized. Upon transfer from a humid to a dry atmosphere, secondary conidia and conidiophores dehydrate and collapse. Mature, dehydrated, secondary conidia are liberated by wind speeds approximately one-third those required to liberate hydrated conidia. The dispersed secondary conidia can rehydrate and germinate normally. Because this microcycle conidiation occurs at the expense of endogenous reserves, the ability to produce secondary conidia is lost after four successive cycles without a period of growth on nutrient media. This alternative method of maintaining inoculum potential during periods of fluctuating relative humidity may have epidemiological consequences when primary conidia fail to infect.

  12. Formation of 1-octen-3-ol from Aspergillus flavus conidia is accelerated after disruption of cells independently of Ppo oxygenases, and is not a main cause of inhibition of germination.

    PubMed

    Miyamoto, Kana; Murakami, Tomoko; Kakumyan, Pattana; Keller, Nancy P; Matsui, Kenji

    2014-01-01

    Eight-carbon (C8) volatiles, such as 1-octen-3-ol, are ubiquitous among fungi. They are the volatiles critical for aroma and flavor of fungi, and assumed to be signals controlling germination of several fungi. In this study, we found that intact Aspergillus flavus conidia scarcely synthesized C8 volatiles but repeated freeze-thaw treatment that made the cell membrane permeable promoted (R)-1-octen-3-ol formation. Loss or down regulation of any one of five fatty acid oxygenases (PpoA, PpoB, PpoC, PpoD or lipoxygenase) hypothesized contribute to 1-octen-3-ol formation had little impact on production of this volatile. This suggested that none of the oxygenases were directly involved in the formation of 1-octen-3-ol or that compensatory pathways exist in the fungus. Germination of the conidia was markedly inhibited at high density (1.0 × 10(9)spores mL(-1)). It has been postulated that 1-octen-3-ol is an autoinhibitor suppressing conidia germination at high density. 1-Octen-3-ol at concentration of no less than 10 mM was needed to suppress the germination while the concentration of 1-octen-3-ol in the suspension at 1.0 × 10(9) mL(-1) was under the detection limit (<1 µM). Thus, 1-octen-3-ol was not the principal component responsible for inhibition of germination. Instead, it was evident that the other heat-labile factor(s) suppressed conidial germination.

  13. Formation of 1-octen-3-ol from Aspergillus flavus conidia is accelerated after disruption of cells independently of Ppo oxygenases, and is not a main cause of inhibition of germination

    PubMed Central

    Miyamoto, Kana; Murakami, Tomoko; Kakumyan, Pattana; Keller, Nancy P.

    2014-01-01

    Eight-carbon (C8) volatiles, such as 1-octen-3-ol, are ubiquitous among fungi. They are the volatiles critical for aroma and flavor of fungi, and assumed to be signals controlling germination of several fungi. In this study, we found that intact Aspergillus flavus conidia scarcely synthesized C8 volatiles but repeated freeze-thaw treatment that made the cell membrane permeable promoted (R)-1-octen-3-ol formation. Loss or down regulation of any one of five fatty acid oxygenases (PpoA, PpoB, PpoC, PpoD or lipoxygenase) hypothesized contribute to 1-octen-3-ol formation had little impact on production of this volatile. This suggested that none of the oxygenases were directly involved in the formation of 1-octen-3-ol or that compensatory pathways exist in the fungus. Germination of the conidia was markedly inhibited at high density (1.0 × 109spores mL−1). It has been postulated that 1-octen-3-ol is an autoinhibitor suppressing conidia germination at high density. 1-Octen-3-ol at concentration of no less than 10 mM was needed to suppress the germination while the concentration of 1-octen-3-ol in the suspension at 1.0 × 109 mL−1 was under the detection limit (<1 µM). Thus, 1-octen-3-ol was not the principal component responsible for inhibition of germination. Instead, it was evident that the other heat-labile factor(s) suppressed conidial germination. PMID:24883255

  14. Human abilities: emotional intelligence.

    PubMed

    Mayer, John D; Roberts, Richard D; Barsade, Sigal G

    2008-01-01

    Emotional intelligence (EI) involves the ability to carry out accurate reasoning about emotions and the ability to use emotions and emotional knowledge to enhance thought. We discuss the origins of the EI concept, define EI, and describe the scope of the field today. We review three approaches taken to date from both a theoretical and methodological perspective. We find that Specific-Ability and Integrative-Model approaches adequately conceptualize and measure EI. Pivotal in this review are those studies that address the relation between EI measures and meaningful criteria including social outcomes, performance, and psychological and physical well-being. The Discussion section is followed by a list of summary points and recommended issues for future research.

  15. Priming Ability Emotional Intelligence

    ERIC Educational Resources Information Center

    Schutte, Nicola S.; Malouff, John M.

    2012-01-01

    Two studies examined whether priming self-schemas relating to successful emotional competency results in better emotional intelligence performance. In the first study participants were randomly assigned to a successful emotional competency self-schema prime condition or a control condition and then completed an ability measure of emotional…

  16. A Specific Calculating Ability.

    ERIC Educational Resources Information Center

    Anderson, Mike; O'Connor, Neil; Hermelin, Beate

    1998-01-01

    Studied the calculating ability used by a low IQ savant to identify prime numbers in two experiments comparing him to control subjects, one involving reaction time and the other involving inspection time. Concludes that this individual uses a complex computational algorithm to identify primes and discusses the apparent contradiction of his low IQ.…

  17. Priming Ability Emotional Intelligence

    ERIC Educational Resources Information Center

    Schutte, Nicola S.; Malouff, John M.

    2012-01-01

    Two studies examined whether priming self-schemas relating to successful emotional competency results in better emotional intelligence performance. In the first study participants were randomly assigned to a successful emotional competency self-schema prime condition or a control condition and then completed an ability measure of emotional…

  18. Ability Is Ageless.

    ERIC Educational Resources Information Center

    Wooten, Andrea

    2002-01-01

    Experience Works is a national organization that provides training and employment services to older adults. Its Prime Time Awards Program honors contributions of older workers in their 70s and beyond, demonstrating the continued ability and productivity of this population as well as the benefits they derive from productive work. (SK)

  19. Computerized Adaptive Ability Measurement.

    ERIC Educational Resources Information Center

    Weiss, David J.

    The general objective of a research program on adaptive testing was to identify several sources of potential error in test scores, and to study adaptive testing as a means for reducing these errors. Errors can result from the mismatch of item difficulty to the individual's ability; the psychological effects of testing and the test environment; the…

  20. Conservatism and Cognitive Ability

    ERIC Educational Resources Information Center

    Stankov, Lazar

    2009-01-01

    Conservatism and cognitive ability are negatively correlated. The evidence is based on 1254 community college students and 1600 foreign students seeking entry to United States' universities. At the individual level of analysis, conservatism scores correlate negatively with SAT, Vocabulary, and Analogy test scores. At the national level of…

  1. Conservatism and Cognitive Ability

    ERIC Educational Resources Information Center

    Stankov, Lazar

    2009-01-01

    Conservatism and cognitive ability are negatively correlated. The evidence is based on 1254 community college students and 1600 foreign students seeking entry to United States' universities. At the individual level of analysis, conservatism scores correlate negatively with SAT, Vocabulary, and Analogy test scores. At the national level of…

  2. Trainability of Abilities.

    DTIC Science & Technology

    1980-06-01

    0 U -) 4-3 CA L ~~( IC 0 4 J CL 4 Cl m I.. 4J .9- s - 04l U 4 0) E .0 0.L 4 -0. 0)0 E L. 0 fa - 0 LUJ’- C. U- 12 Experimental Design and Procedures A...F DAOS 520 ADVANCED RESEARCH RESOURCES ORGANIZATION WASHINGTON OC F/ S 5/9 TRAINABILITY OF ABILITIES.CU) jUN 80 J M LEVINE N0O014-7--0268 UNCLASSIFIED...00naIvepED /Trainability of Abilities,/lMr7lMrr 7. AUTNOR(e)_ D.i".e~n 2~ CONTRACT DWUWRATTUMBER( s ) ’/N00014-77-C-0268r PERFORMING ORGANIZATION

  3. Music and nonmusical abilities.

    PubMed

    Schellenberg, E G

    2001-06-01

    Reports that exposure to music causes benefits in nonmusical domains have received widespread attention in the mainstream media. Such reports have also influenced public policy. The so-called "Mozart effect" actually refers to two relatively distinct phenomena. One concerns short-term increases in spatial abilities that are said to occur from listening to music composed by Mozart. The other refers to the possibility that formal training in music yields nonmusical benefits. A review of the relevant findings indicates that the short-term effect is small and unreliable. Moreover, when it is evident, it can be explained by between-condition differences in the listener's mood or levels of cognitive arousal. By contrast, the effect of music lessons on nonmusical aspects of cognitive development is still an open question. Several studies have reported positive associations between formal music lessons and abilities in nonmusical (e.g., linguistic, mathematical, and spatial) domains. Nonetheless, compelling evidence for a causal link remains elusive.

  4. A Mechanistic Model of Botrytis cinerea on Grapevines That Includes Weather, Vine Growth Stage, and the Main Infection Pathways

    PubMed Central

    González-Domínguez, Elisa; Caffi, Tito; Ciliberti, Nicola; Rossi, Vittorio

    2015-01-01

    A mechanistic model for Botrytis cinerea on grapevine was developed. The model, which accounts for conidia production on various inoculum sources and for multiple infection pathways, considers two infection periods. During the first period (“inflorescences clearly visible” to “berries groat-sized”), the model calculates: i) infection severity on inflorescences and young clusters caused by conidia (SEV1). During the second period (“majority of berries touching” to “berries ripe for harvest”), the model calculates: ii) infection severity of ripening berries by conidia (SEV2); and iii) severity of berry-to-berry infection caused by mycelium (SEV3). The model was validated in 21 epidemics (vineyard × year combinations) between 2009 and 2014 in Italy and France. A discriminant function analysis (DFA) was used to: i) evaluate the ability of the model to predict mild, intermediate, and severe epidemics; and ii) assess how SEV1, SEV2, and SEV3 contribute to epidemics. The model correctly classified the severity of 17 of 21 epidemics. Results from DFA were also used to calculate the daily probabilities that an ongoing epidemic would be mild, intermediate, or severe. SEV1 was the most influential variable in discriminating between mild and intermediate epidemics, whereas SEV2 and SEV3 were relevant for discriminating between intermediate and severe epidemics. The model represents an improvement of previous B. cinerea models in viticulture and could be useful for making decisions about Botrytis bunch rot control. PMID:26457808

  5. General English Ability, Specific Purpose English Ability, and Computer Skills.

    ERIC Educational Resources Information Center

    Prapphal, Kanchana

    2003-01-01

    Aims to answer the following research questions: (1) Are general English ability and specific purpose English ability related to computer skills? and (2) Is general English ability transferable to specific purpose English ability? Subjects were third year science students enrolled in an English for academic purposes course. (Author/VWL)

  6. General English Ability, Specific Purpose English Ability, and Computer Skills.

    ERIC Educational Resources Information Center

    Prapphal, Kanchana

    2003-01-01

    Aims to answer the following research questions: (1) Are general English ability and specific purpose English ability related to computer skills? and (2) Is general English ability transferable to specific purpose English ability? Subjects were third year science students enrolled in an English for academic purposes course. (Author/VWL)

  7. Evaluation of the control ability of five essential oils against Aspergillus section Nigri growth and ochratoxin A accumulation in peanut meal extract agar conditioned at different water activities levels.

    PubMed

    Passone, María A; Girardi, Natalia S; Etcheverry, Miriam

    2012-10-15

    Essential oils (EOs) from boldo [Pëumus boldus Mol.], poleo [Lippia turbinata var. integrifolia (Griseb.)], clove [Syzygium aromaticum L.], anise [Pimpinella anisum] and thyme [Thymus vulgaris]) obtained by hydrodistillation were evaluated for their effectiveness against the growth of Aspergillus niger aggregate and A. carbonarius and accumulation of ochratoxin A (OTA). The evaluation was performed by compound dissolution at the doses of 0, 500, 1500 and 2500μL/L in peanut meal extract agar (PMEA) and exposure to volatiles of boldo, poleo (0, 1000, 2000 and 3000μL/L) and clove oils (0, 1000, 3000 and 5000μL/L), taking into account the levels of the water activity of the medium (a(W) 0.98, 0.95, 0.93). Statistical analyses on growth of Aspergillus strains indicated that the major effect was produced by oil concentrations followed by substrate a(W), and that reductions in antifungal efficiency of the oils tested were observed in vapor exposure assay. At all a(W) levels, complete fungal growth inhibition was achieved with boldo EO at doses of 1500 and 2000μL/L by contact and volatile assays, respectively. Contact exposure by poleo and clove EOs showed total fungal inhibition at the middle level tested of 1500μL/L, regardless of a(W), while their antifungal effects in headspace volatile assay were closely dependent on medium a(W). The fumigant activity of poleo (2000μL/L) and clove oils (3000μL/L) inhibited growth rate by 66.0% and 80.6% at a(W) 0.98 and 0.93, respectively. OTA accumulation was closely dependent on a(W) conditions. The antiochratoxigenic property of the volatile fractions of boldo, poleo and clove EOs (1000μL/L) was more significant at low a(W) levels, inhibition percentages were estimated at 14.7, 41.7 and 78.5% at a(W) 0.98, 0.95 and 0.93, respectively. Our results suggest that boldo, poleo and clove oils affect the OTA biosynthesis pathway of both Aspergillus species. This finding leaves open the possibility of their use by vapor exposure

  8. Comparison of the abilities of human parathyroid hormone (hPTH)-(1-34) and [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 to stimulate femoral trabecular bone growth in ovariectomized rats.

    PubMed

    Whitfield, J F; Morley, P; Willick, G; MacLean, S; Ross, V; Isaacs, R J; Barbier, J R

    1998-11-01

    hPTH-(1-31)NH2, so far the smallest of the potently anabolic N-terminal fragments of the human parathyroid hormone, stimulates trabecular growth in the distal femurs of ovariectomized (OVX) rats as strongly as hPTH-(1-34) when injected at a high daily dose such as 1 nmol/100 g of body weight, but it is only about 70% as effective as hPTH-(1-34) when injected at the suboptimal 0.6 nmol/100 g of body weight. A lactam derivative of hPTH-(1-31)-NH2, [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2, is a much more effective stimulator of adenylyl cyclase in ROS 17/2 rat osteoblast-like cells and a significantly more effective stimulator of femoral trabecular growth in OVX rats than hPTH-(1-31)NH2. We have now shown that [Leu27]-cyclo(Glu22-Lys26)-hPTH-(1-31)NH2 prevents the OVX-induced loss of femoral trabeculae significantly more effectively than hPTH-(1-34) and stimulates the thickening of the trabeculae remaining in severely depleted femoral trabecular bone of OVX rats as effectively as hPTH-(1-34) when injected at 0.6 nmol/100 g of body weight.

  9. Ability Grouping in Physical Education.

    ERIC Educational Resources Information Center

    Kneer, Marian E.

    1982-01-01

    Psychomotor ability differences in students are a result of innate motor ability, fitness, neurologic development, psychology, experience, and students' interests and goals. Models and procedures for serving students with ability differences, in the areas of ability identification, curriculum development, and instruction, are described. (CJ)

  10. Filipin is a reliable in situ marker of ergosterol in the plasma membrane of germinating conidia (spores) of Penicillium discolor and stains intensively at the site of germ tube formation.

    PubMed

    Van Leeuwen, M R; Smant, W; de Boer, W; Dijksterhuis, J

    2008-08-01

    Filipin, a widely used fluorescent sterol marker is also a potent antibiotic. In this study we address the reliability of filipin as a monitor of ergosterol in fungal cells. A revised staining protocol was developed to minimize any biological effect of the compound. Germinating conidia of Penicillium discolor stained with filipin, displayed a fluorescent cap at the location of germ tube appearance and formation. During germ tube emergence, the fluorescent intensity of the cap increased. This was confirmed by HPLC as an increase of the net cellular ergosterol content. Filipin staining is absent during early germination, while FM dyes, similar molecules, stain the plasma membrane after 1 h. This indicates that the conidial cell wall is no barrier for filipin. To evaluate if filipin does bind ergosterol in situ, natamycin, more specific to ergosterol, was added before filipin staining. This resulted in a marked decrease in fluorescence indicating high ergosterol levels. This was characterized further in ergDelta-mutant cells of Saccharomyces cerevisiae containing altered sterols. Here ergosterol containing cells showed a high fluorescence decrease. Taken together, these data suggest that filipin monitors an ergosterol-enriched cap in germinating conidia at the site of germ tube formation. Furthermore, the sterol-rich cap decreases and reappears after a period of actin disruption. Myriocin that affects sphingolipid synthesis results in an increase of cellular ergosterol and overall filipin fluorescence, but not at the ergosterol cap, where fluorescence is significantly lowered. In conclusion, in this work we have demonstrated an effective revised method for ergosterol staining with filipin and demonstrated its specificity in both Penicillium and Saccharomyces.

  11. Development of an in vitro macrophage system to assess Penicillium marneffei growth and susceptibility to nitric oxide.

    PubMed Central

    Cogliati, M; Roverselli, A; Boelaert, J R; Taramelli, D; Lombardi, L; Viviani, M A

    1997-01-01

    We investigated the effect of nitric oxide (NO) and reactive nitrogen intermediates on the in vitro growth of Penicillium marneffei both in a cell-free system and in a novel macrophage culture system. In the cell-free system, NO that was chemically generated from NaNO2 in acid media (pH 4 and 5) markedly inhibited the growth of P. marneffei. On the contrary, inhibition of growth did not occur in neutral medium (pH 7.4) in which NO was not produced. P. marneffei conidia were phagocytized by nonstimulated murine J774 macrophages after 2 h of incubation. During the following 24 h, P. marneffei grew as yeast-like cells replicating by fission in the J774 macrophages. The intracellular growth of P. marneffei damaged nonstimulated J774 macrophages, as confirmed by electron microscopy. When J774 cells were stimulated by gamma interferon and lipopolysaccharide, which led to enhanced production of reactive nitrogen intermediates, the percentage of yeast-like cells was significantly reduced and P. marneffei conidia were damaged in the J774 macrophages. The inhibition of NO synthesis by N-monomethyl-L-arginine restored the intracellular growth of P. marneffei. The inverse correlation between intramacrophage growth and the amount of nitrite detected in culture supernatants supports the hypothesis that the L-arginine-dependent NO pathway plays an important role in the murine macrophage immune response against P. marneffei. PMID:8975924

  12. Pre-Service Teachers' Mindset Beliefs about Student Ability

    ERIC Educational Resources Information Center

    Gutshall, C. Anne

    2014-01-01

    Introduction: We all have beliefs about our ability or intelligence. The extent to which we believe ability is malleable (growth) or stable (fixed) is commonly referred to as our mindset. This research is designed to explore pre-service teachers' mindset beliefs as well as their beliefs when applied to hypothetical student scenarios. Method:…

  13. Monoclonal Antibodies against Epidermal Growth Factor Receptor Acquire an Ability To Kill Tumor Cells through Complement Activation by Mutations That Selectively Facilitate the Hexamerization of IgG on Opsonized Cells.

    PubMed

    Tammen, Annalina; Derer, Stefanie; Schwanbeck, Ralf; Rösner, Thies; Kretschmer, Anna; Beurskens, Frank J; Schuurman, Janine; Parren, Paul W H I; Valerius, Thomas

    2017-02-15

    Triggering of the complement cascade induces tumor cell lysis via complement-dependent cytotoxicity (CDC) and attracts and activates cytotoxic cells. It therefore represents an attractive mechanism for mAb in cancer immunotherapy development. The classical complement pathway is initiated by IgG molecules that have assembled into ordered hexamers after binding their Ag on the tumor cell surface. The requirements for CDC are further impacted by factors such as Ab epitope, valency, and affinity. Thus, mAb against well-validated solid tumor targets, such as the epidermal growth factor receptor (EGFR) that effectively induces complement activation and CDC, are highly sought after. The potency of complement activation by IgG Abs can be increased via several strategies. We identified single-point mutations in the Fc domain (e.g., E345K or E430G) enhancing Fc:Fc interactions, hexamer formation, and CDC after Ab binds cell-surface Ag. We show that EGFR Abs directed against clinically relevant epitopes can be converted into mAb with unprecedented CDC activity. Alternative strategies rely on increasing the affinity of monomeric IgG for C1q by introduction of a quadruple mutation at the C1q binding site or via generation of an IgG1/IgG3 chimera. In this study we show that selective enhancement of C1q binding via avidity modulation is superior to the unattended increase in C1q binding via affinity approaches, particularly for target cells with reduced EGFR expression levels. Improving Fc:Fc interactions of Ag-bound IgG therefore represents a highly promising and novel approach for potentiating the anti-tumor activity of therapeutic mAb against EGFR and potentially other tumor targets.

  14. Information Processing and Human Abilities

    ERIC Educational Resources Information Center

    Kirby, John R.; Das, J. P.

    1978-01-01

    The simultaneous and successive processing model of cognitive abilities was compared to a traditional primary mental abilities model. Simultaneous processing was found to be primarily related to spatial ability; and to a lesser extent, to memory and inductive reasoning. Subjects were 104 fourth-grade urban males. (Author/GD C)

  15. Production of an Extracellular Matrix as an Isotropic Growth Phase of Penicillium rubens on Gypsum

    PubMed Central

    Bekker, M.; Adan, O. C. G.; Samson, R. A.; Wyatt, T.; Dijksterhuis, J.

    2012-01-01

    Indoor mold represents an important environmental concern, but a fundamental knowledge of fungal growth stages is needed to limit indoor fungal proliferation on finishing materials used in buildings. The present study focused on the succession of germination stages of the common indoor fungus Penicillium rubens on a gypsum substrate. This substrate is used as a model system representing porous materials that are widely used in indoor environments. Imaging with cryo-scanning electron microscopy showed that the formation of an extracellular matrix (ECM) is a phase of the isotropic growth of P. rubens that is uniquely related to germinating conidia. Furthermore, the ECM is observed only when a dry-state inoculation of the surface is applied, i.e., applying conidia directly from a 7-day-old colony, mimicking airborne contamination of the surface. When inoculation is done by spraying an aqueous conidial suspension, no ECM is observed. Moreover, it is concluded that the formation of an ECM requires active processes in the fungal cell. The porosity of the substrate proved that the ECM substance has high-viscosity characteristics. The present results stress that studies of indoor fungal growth should consider the method of inoculation, knowing that the common aqueous suspension may obscure specific stages in the initial phases of germination. PMID:22843536

  16. Specific Abilities May Increment Psychometric g for High Ability Populations

    DTIC Science & Technology

    2016-04-14

    1973). The validity of aptitude tests in personnel selection. Personnel Psychology , 26, 461- 477. Hartmann, P. H., & Nyborg, H. (2004). Spearman’s...1979). Use of the position analysis questionnaire for establishing the job component validity of tests . Journal of Applied Psychology , 64, 51...that correlations among cognitive ability tests are lower for higher ability groups, yet higher for low-ability groups. SLODR also suggests that

  17. Effect of temperature and water activity on spore germination and mycelial growth of three fungal biocontrol agents against water hyacinth (Eichhornia crassipes).

    PubMed

    Dagno, K; Lahlali, R; Diourté, M; Jijakli, M H

    2011-02-01

    To determine the effect of water activity (a(w) =0·880-0·960) and temperature (15-35°C) on the percentage of viable conidia and mycelial growth of three biocontrol agents effective against water hyacinth in Mali: Alternaria sp. isolate Mlb684, Fusarium sacchari isolate Mln799 and Cadophora malorum isolate Mln715. The fungi were grown in vitro on plates containing potato dextrose agar medium at different a(w) values (glycerol being added to adjust the a(w)). The percentage of viable conidia and radial growth rate decreased with decreasing water activity. Statistical analysis showed a significant effect of a(w), temperature and the a(w) × temperature interaction on mycelial growth (P<0·0001). Water activity emerged as the factor exerting the greatest influence. Differences were observed between the fungi tested, the C. malorum appearing more tolerant to low a(w) and the F. sacchari more tolerant to high temperature (35°C). Growth models predicting the combined effect of a(w) and temperature were developed and response surfaces generated, showing fairly good agreement with the experimental values. Our results confirm the previous finding that a(w) has a greater influence than temperature on fungal growth. Under most conditions, variation of environmental factors has a detrimental influence on the percentage of viable conidia and mycelial growth rate of fungal isolates. The developed models may contribute to predicting the best environmental conditions for use of these fungi as effective biocontrol agents against water hyacinth. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

  18. Optimization of the medium composition of a biphasic production system for mycelial growth and spore production of Aschersonia placenta using response surface methodology.

    PubMed

    Qiu, Junzhi; Song, Feifei; Qiu, Yunfeng; Li, Xiaoxia; Guan, Xiong

    2013-02-01

    The culture media for mycelial growth and sporulation of the entomopathogenic fungus Aschersonia placenta were optimized using the response surface method (RSM). Interactions of medium components and the optimization of a biphasic production system were studied using Box-Behnken design (BBD) with three levels of three variables. Experimentation confirmed that the model developed based on RSM and BBD successfully predicted mycelia production (R(2) = 0.9336) and conidia production (R(2) = 0.9532). In the first phase, mycelial dry weight was highest (2.14 ± 0.17 g per 100ml of culture, mean±SE) when the concentrations (g/l) of glucose, vitamin B(6), and MgSO(4)·7H(2)O were 31.4, 11.5, and 0.64, respectively. In the second phase, conidia production was highest (9.31 ± 0.48 × 10(7)sporespercm(2)) after 18d of cultivation in the medium containing 33.8 g/l of millet, 1.11 g/l of KH(2)PO(4), and 0.37 g/l of MgSO(4). Mycelial and conidial yields were 3.6- and 10-fold greater, respectively, with the optimized media than with the non-optimized basal media. The results indicate that RSM and BBD methods are effective for increasing the production of A. placenta mycelia and conidia.

  19. Influence of culture media and environmental factors on mycelial growth and pycnidial production of Sphaeropsis pyriputrescens.

    PubMed

    Kim, Y K; Xiao, C L; Rogers, J D

    2005-01-01

    Sphaeropsis pyriputrescens, the causal agent of Sphaeropsis rot of pears and apples, is a recently described species. In this study the effects of culture media, temperature, water potential, pH and light on mycelial growth and pycnidial production of S. pyriputrescens were evaluated. Apple juice agar and pear juice agar were most suitable for mycelial growth of all six isolates tested. Cornmeal agar was not suitable for either mycelial growth or pycnidial production. The fungus grew from -3 to 25 C, with optimum growth at 20 C and no growth at 30 C. The fungus grew at water potential as low as -5.6 MPa on potassium chloride-amended potato-dextrose agar (PDA). Hyphal extension was not observed at -7.3 MPa after 10 d incubation, but growth resumed when the inoculum plugs were placed on PDA. The fungus grew at pH 3.3-6.3 and optimum growth was at pH 3.3-4.2. No mycelial growth was observed at pH above 7.2 after 10 d incubation, but growth resumed when the inoculum plugs were transferred onto PDA. Regardless of medium tested, few pycnidia formed at 20 C in the dark. Pycnidial production was enhanced significantly by fluorescent light, but continuous light appeared to reduce pycnidial production, depending on the medium. Oatmeal agar (OMA) was most suitable for production of pycnidia and conidia. Pycnidia that formed on 3 wk old OMA cultures at 20 C under 12 h light/12 h dark produced abundant conidia, and the technique is recommended for inoculum production.

  20. Radial plant growth.

    PubMed

    Tonn, Nina; Greb, Thomas

    2017-09-11

    One of the extraordinary features of plants is their growth capacity. Depending on the species and the environment, body forms are manifold and, at the same time, constantly reshaped. An important basis of this plastic variation and life-long accumulation of biomass is radial growth. Here, we use this term to describe the ability to grow in girth by the formation of wood, bast and cork. The more technical term for radial growth is secondary growth, which distinguishes the process from primary growth taking place at the tips of stems and roots during plant elongation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Diver First Class Reading Ability.

    ERIC Educational Resources Information Center

    Bain, E. C., III; Berghage, T. E.

    The Nelson-Denny reading test was administered to thirty Navy first class diver candidates to evaluate the group's vocabulary, reading comprehension, reading rate and over-all reading ability. Reading rate and comprehension were at the twelfth grade level, while vocabulary ability was equal to the college freshman norm. (Author)

  2. Implicit Learning as an Ability

    ERIC Educational Resources Information Center

    Kaufman, Scott Barry; DeYoung, Caroline G.; Gray, Jeremy R.; Jimenez, Luis; Brown, Jamie; Mackintosh, Nicholas

    2010-01-01

    The ability to automatically and implicitly detect complex and noisy regularities in the environment is a fundamental aspect of human cognition. Despite considerable interest in implicit processes, few researchers have conceptualized implicit learning as an ability with meaningful individual differences. Instead, various researchers (e.g., Reber,…

  3. Assessment of English Speaking Ability.

    ERIC Educational Resources Information Center

    Nakamura, Yuji

    1996-01-01

    The purpose of this research is to examine the detailed components of Japanese students' English speaking ability in terms of communicative competence by using an oral proficiency test based on Bachman's Communicative Language Ability model (included in an appendix). Eighty college students were tested on four tasks--speech making, visual material…

  4. The Measurement of Translation Ability.

    ERIC Educational Resources Information Center

    Stansfield, Charles W.; And Others

    1992-01-01

    Variables that constitute translation ability are discussed, based on a two-year development and validation study of job-related tests of translation ability for the Federal Bureau of Investigation. The project involved the development of two parallel forms of the Spanish into English Verbatim Translation Exam (SEVTE). (five references) (LB)

  5. Implicit Learning as an Ability

    ERIC Educational Resources Information Center

    Kaufman, Scott Barry; DeYoung, Caroline G.; Gray, Jeremy R.; Jimenez, Luis; Brown, Jamie; Mackintosh, Nicholas

    2010-01-01

    The ability to automatically and implicitly detect complex and noisy regularities in the environment is a fundamental aspect of human cognition. Despite considerable interest in implicit processes, few researchers have conceptualized implicit learning as an ability with meaningful individual differences. Instead, various researchers (e.g., Reber,…

  6. Mixed Ability Teaching Versus Streaming.

    ERIC Educational Resources Information Center

    Marklund, Sixten

    1984-01-01

    Discusses development of pupil grouping in European compulsory education into two opposite class organization types, mixed ability classes and ability-grouped classes. Categorizes the types along two dimensions with three program types and three grouping types, yielding nine teaching categories. Discusses comparative results of streaming and mixed…

  7. Strategies of Adaptive Ability Measurement.

    ERIC Educational Resources Information Center

    Weiss, David J.

    A number of strategies are described for adapting ability test items to individual differences in ability levels of testees. Each strategy consists of a different set of rules for selecting the sequence of test items to be administered to a given testee. Advantages and disadvantages of each strategy are discussed, and research issues unique to the…

  8. Perceptual Processes and Cognitive Ability.

    ERIC Educational Resources Information Center

    Schweizer, Karl; Koch, Wolfgang

    2003-01-01

    Examined the contribution of perceptual processes to cognitive ability with respect to stimulus complexity, response mode, level of encoding, and attention. Findings for 124 college students show that about 70% of common variance of perceptual processes and cognitive ability was due to attentive processes, with 30% resulting from pre-attentive…

  9. Growth hormone and growth?

    PubMed

    Harvey, Steve

    2013-09-01

    Pituitary GH is obligatory for normal growth in mammals, but the importance of pituitary GH in avian growth is less certain. In birds, pituitary GH is biologically active and has growth promoting actions in the tibia-test bioassay. Its importance in normal growth is indicated by the growth suppression following the surgical removal of the pituitary gland or after the immunoneutralization of endogenous pituitary GH. The partial restoration of growth in some studies with GH-treated hypophysectomized birds also suggests GH dependency in avian growth, as does the dwarfism that occurs in some strains with GHR dysfunctions. Circulating GH concentrations are also correlated with body weight gain, being high in young, rapidly growing birds and low in slower growing older birds. Nevertheless, despite these observations, there is an extensive literature that concludes pituitary GH is not important in avian growth. This is based on numerous studies with hypophysectomized and intact birds that show only slight, transitory or absent growth responses to exogenous GH-treatment. Moreover, while circulating GH levels correlate with weight gain in young birds, this may merely reflect changes in the control of pituitary GH secretion during aging, as numerous studies involving experimental alterations in growth rate fail to show positive correlations between plasma GH concentrations and the alterations in growth rate. Furthermore, growth is known to occur in the absence of pituitary GH, as most embryonic development occurs prior to the ontogenetic appearance of pituitary somatotrophs and the appearance of GH in embryonic circulation. Early embryonic growth is also independent of the endocrine actions of pituitary GH, since removal of the presumptive pituitary gland does not impair early growth. Embryonic growth does, however, occur in the presence of extrapituitary GH, which is produced by most tissues and has autocrine or paracrine roles that locally promote growth and development

  10. MoLys2 is necessary for growth, conidiogenesis, lysine biosynthesis, and pathogenicity in Magnaporthe oryzae.

    PubMed

    Chen, Yue; Zuo, Rongfang; Zhu, Qian; Sun, Yi; Li, Mengying; Dong, Yanhan; Ru, Yanyan; Zhang, Haifeng; Zheng, Xiaobo; Zhang, Zhengguang

    2014-06-01

    Amino acid biosyntheses are complex but essential processes in growth and differentiation of eukaryotic cells. In the budding yeast Saccharomyces cerevisiae, the lysine biosynthesis via the α-aminoadipate (AA) pathway involves several steps, including reduction of AA to AA 6-semialdehyde by AA reductase ScLys2. In filamentous fungus Penicillium chrysogenum, disruption of the LYS2 gene blocked the lysine biosynthesis but promoted the production of the secondary metabolite penicillin. In comparison, little is known about the function of AA reductase Lys2 in phytopathogenic fungi. We here characterized the functions of MoLys2, a homolog of ScLys2, from the rice blast fungus Magnaporthe oryzae. Our results showed that the ΔMolys2 mutants were auxotrophic for lysine. The ΔMolys2 mutants also exhibited drastic reduction in pathogenicity on rice, inducing small disease lesions. Microscopic examination of the lesions revealed that the invasive hyphae of ΔMolys2 mutants were mostly restricted to the primary infected leaf sheath cells. In addition, exogenous lysine restored the production of conidia and near wild-type appressoria differentiation, and rescued the defect of pathogenicity in conidia infection of detached barely and rice leaf sheath. Our results indicated that MoLys2 is necessary for lysine biosynthesis that affects growth, conidiogenesis, and pathogenicity of the fungus. This study does implicate the potential for targeting lysine biosynthesis for the development of novel fungicides against M. oryzae. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. NETs formed by human neutrophils inhibit growth of the pathogenic mold Aspergillus fumigatus.

    PubMed

    McCormick, Allison; Heesemann, Leonie; Wagener, Johannes; Marcos, Veronica; Hartl, Dominik; Loeffler, Jürgen; Heesemann, Jürgen; Ebel, Frank

    2010-11-01

    Neutrophil extracellular traps (NETs) represent a distinct mechanism to control and eliminate microbial infections. Our results show that conidia and germ tubes of the human pathogenic mold Aspergillus fumigatus are able to trigger the formation of NETs. Viable fungal cells are not essentially required for this host-pathogen interaction. Neutrophils engulf conidia and thereby inhibit their germination, a process that is independent of NETosis. In the experimental set-up used in this study neutrophils do not kill germ tubes, but reduce their polar growth and this inhibition depends on NETs as it can be overcome by the addition of DNase-1. The Zn(2+) chelator calprotectin is associated with the Aspergillus-induced NETs and addition of Zn(2+) abrogates the NET-mediated growth inhibition. In summary, our data provide evidence that NETs are not sufficient to kill A. fumigatus, but might be a valuable tool to confine infection. Copyright © 2010 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  12. Exceptional cognitive ability: the phenotype.

    PubMed

    Lubinski, David

    2009-07-01

    Characterizing the outcomes related to the phenotype of exceptional cognitive abilities has been feasible in recent years due to the availability of large samples of intellectually precocious adolescents identified by modern talent searches that have been followed-up longitudinally over multiple decades. The level and pattern of cognitive abilities, even among participants within the top 1% of general intellectual ability, are related to differential developmental trajectories and important life accomplishments: The likelihood of earning a doctorate, earning exceptional compensation, publishing novels, securing patents, and earning tenure at a top university (and the academic disciplines within which tenure is most likely to occur) all vary as a function of individual differences in cognitive abilities assessed decades earlier. Individual differences that distinguish the able (top 1 in 100) from the exceptionally able (top 1 in 10,000) during early adolescence matter in life, and, given the heritability of general intelligence, they suggest that understanding the genetic and environmental origins of exceptional abilities should be a high priority for behavior genetic research, especially because the results for extreme groups could differ from the rest of the population. In addition to enhancing our understanding of the etiology of general intelligence at the extreme, such inquiry may also reveal fundamental determinants of specific abilities, like mathematical versus verbal reasoning, and the distinctive phenotypes that contrasting ability patterns are most likely to eventuate in at extraordinary levels.

  13. Balance ability and athletic performance.

    PubMed

    Hrysomallis, Con

    2011-03-01

    The relationship between balance ability and sport injury risk has been established in many cases, but the relationship between balance ability and athletic performance is less clear. This review compares the balance ability of athletes from different sports, determines if there is a difference in balance ability of athletes at different levels of competition within the same sport, determines the relationship of balance ability with performance measures and examines the influence of balance training on sport performance or motor skills. Based on the available data from cross-sectional studies, gymnasts tended to have the best balance ability, followed by soccer players, swimmers, active control subjects and then basketball players. Surprisingly, no studies were found that compared the balance ability of rifle shooters with other athletes. There were some sports, such as rifle shooting, soccer and golf, where elite athletes were found to have superior balance ability compared with their less proficient counterparts, but this was not found to be the case for alpine skiing, surfing and judo. Balance ability was shown to be significantly related to rifle shooting accuracy, archery shooting accuracy, ice hockey maximum skating speed and simulated luge start speed, but not for baseball pitching accuracy or snowboarding ranking points. Prospective studies have shown that the addition of a balance training component to the activities of recreationally active subjects or physical education students has resulted in improvements in vertical jump, agility, shuttle run and downhill slalom skiing. A proposed mechanism for the enhancement in motor skills from balance training is an increase in the rate of force development. There are limited data on the influence of balance training on motor skills of elite athletes. When the effectiveness of balance training was compared with resistance training, it was found that resistance training produced superior performance results for

  14. [Driving ability with multiple sclerosis].

    PubMed

    Küst, J; Dettmers, C

    2014-07-01

    Driving is an important issue for young patients, especially for those whose walking capacity is impaired. Driving might support the patient's social and vocational participation. The question as to whether a patient with multiple sclerosis (MS) is restricted in the ability to drive a car depends on neurological and neuropsychological deficits, self-awareness, insight into deficits and ability to compensate for loss of function. Because of the enormous variability of symptoms in MS the question is highly individualized. A practical driving test under supervision of a driving instructor (possibly accompanied by a neuropsychologist) might be helpful in providing both patient and relatives adequate feedback on driving abilities.

  15. Measuring Management Abilities and Motivation.

    ERIC Educational Resources Information Center

    Howard, Ann

    1983-01-01

    The complexity of managerial abilities and motivation is displayed in the assessment center method, where judgments depend on a comprehensive package of such techniques as paper-and-pencil tests, interviews, simulations, and projective tests. (Author)

  16. Numerical ability predicts mortgage default

    PubMed Central

    Gerardi, Kristopher; Goette, Lorenz; Meier, Stephan

    2013-01-01

    Unprecedented levels of US subprime mortgage defaults precipitated a severe global financial crisis in late 2008, plunging much of the industrialized world into a deep recession. However, the fundamental reasons for why US mortgages defaulted at such spectacular rates remain largely unknown. This paper presents empirical evidence showing that the ability to perform basic mathematical calculations is negatively associated with the propensity to default on one’s mortgage. We measure several aspects of financial literacy and cognitive ability in a survey of subprime mortgage borrowers who took out loans in 2006 and 2007, and match them to objective, detailed administrative data on mortgage characteristics and payment histories. The relationship between numerical ability and mortgage default is robust to controlling for a broad set of sociodemographic variables, and is not driven by other aspects of cognitive ability. We find no support for the hypothesis that numerical ability impacts mortgage outcomes through the choice of the mortgage contract. Rather, our results suggest that individuals with limited numerical ability default on their mortgage due to behavior unrelated to the initial choice of their mortgage. PMID:23798401

  17. Numerical ability predicts mortgage default.

    PubMed

    Gerardi, Kristopher; Goette, Lorenz; Meier, Stephan

    2013-07-09

    Unprecedented levels of US subprime mortgage defaults precipitated a severe global financial crisis in late 2008, plunging much of the industrialized world into a deep recession. However, the fundamental reasons for why US mortgages defaulted at such spectacular rates remain largely unknown. This paper presents empirical evidence showing that the ability to perform basic mathematical calculations is negatively associated with the propensity to default on one's mortgage. We measure several aspects of financial literacy and cognitive ability in a survey of subprime mortgage borrowers who took out loans in 2006 and 2007, and match them to objective, detailed administrative data on mortgage characteristics and payment histories. The relationship between numerical ability and mortgage default is robust to controlling for a broad set of sociodemographic variables, and is not driven by other aspects of cognitive ability. We find no support for the hypothesis that numerical ability impacts mortgage outcomes through the choice of the mortgage contract. Rather, our results suggest that individuals with limited numerical ability default on their mortgage due to behavior unrelated to the initial choice of their mortgage.

  18. Loss of msnA, a Putative Stress Regulatory Gene, in Aspergillus parasiticus and Aspergillus flavus Increased Production of Conidia, Aflatoxins and Kojic Acid

    PubMed Central

    Chang, Perng-Kuang; Scharfenstein, Leslie L.; Luo, Meng; Mahoney, Noreen; Molyneux, Russell J.; Yu, Jiujiang; Brown, Robert L.; Campbell, Bruce C.

    2011-01-01

    Production of the harmful carcinogenic aflatoxins by Aspergillus parasiticus and Aspergillus flavus has been postulated to be a mechanism to relieve oxidative stress. The msnA gene of A. parasiticus and A. flavus is the ortholog of Saccharomyces cerevisiae MSN2 that is associated with multi-stress response. Compared to wild type strains, the msnA deletion (∆msnA) strains of A. parasiticus and A. flavus exhibited retarded colony growth with increased conidiation. The ∆msnA strains also produced slightly higher amounts of aflatoxins and elevated amounts of kojic acid on mixed cereal medium. Microarray assays showed that expression of genes encoding oxidative stress defense enzymes, i.e., superoxide dismutase, catalase, and cytochrome c peroxidase in A. parasiticus ∆msnA, and the catalase A gene in A. flavus ∆msnA, was up-regulated. Both A. parasiticus and A. flavus ∆msnA strains produced higher levels of reactive oxygen species (ROS), and ROS production of A. flavus msnA addback strains was decreased to levels comparable to that of the wild type A. flavus. The msnA gene appears to be required for the maintenance of the normal oxidative state. The impairment of msnA resulted in the aforementioned changes, which might be used to combat the increased oxidative stress in the cells. PMID:22069691

  19. Lifestyle index and work ability.

    PubMed

    Kaleta, Dorota; Makowiec-Dabrowska, Teresa; Jegier, Anna

    2006-01-01

    In many countries around the world, negative changes in lifestyles are observed. The aim of this study was to analyze the influence of selected lifestyle indicators on work ability among professionally active individuals. The study was performed in the randomly selected group of full-time employees (94 men and 93 women) living in the city of Lódź. Work ability was measured with the work ability index and lifestyle characteristic was assessed with the healthy lifestyle index. We analyzed four lifestyle indicators: non-smoking, healthy weight, fiber intake per day, and regular physical activity. Logistic regression was used to estimate odds ratios and 95% confidence intervals to control the effects of lifestyle and work ability. The analysis of lifestyle index indicated that 27.7, 30.9, 27.7 and 11.7% of men and 15.1, 21.5, 35.5 and 26.9% of women scored 0, 1, 2, 3 points, respectively. Only 2.1% of men and 1.1% of women met the criteria for the healthy lifestyle (score 4). Work ability was excellent, good and moderate in 38.3, 46.8 and 14.9% of men, and in 39.8, 14.9 and 19.3% of women, respectively. Poor work ability was found in 9.7% women. Work ability was strongly associated with lifestyle in both men and women. Among men with index score = 0, the risk of moderate work ability was nearly seven times higher than in men whose lifestyle index score exceeded 1 or more points (OR = 6.67; 95% CI: 1.94-22.90). Among women with lifestyle index score = 0, the risk of moderate or lower work ability was also highly elevated as compared to those with lifestyle index = 1 or higher (OR = 14.44; 95% CI: 3.53-59.04). Prophylactic schedules associated with the improvement of lifestyles should be addressed to all adults. Future programs aimed at increasing work ability should consider work- and lifestyle-related factors.

  20. EXPLORATORY RESEARCH ON COMMUNICATION ABILITIES AND CREATIVE ABILITIES.

    ERIC Educational Resources Information Center

    TAYLOR, CALVIN W.; AND OTHERS

    THIS STUDY SOUGHT TO IDENTIFY VARIABLES RELATED TO EFFECTIVENESS OF COMMUNICATION IN MILITARY OPERATIONS. THE GOAL WAS TO DEVELOP TESTS TO CLASSIFY OFFICERS AND AIRMEN, BASED UPON ALL OF THE BROAD COMMUNICATION ABILITIES NEEDED IN THE AIR FORCE. THE RESEARCH OUTLINE CONSISTED OF REVIEWING COMMUNICATION STUDIES AND OTHER TESTS, PREPARING A REDUCED…

  1. Inhibitory Control Predicts Grammatical Ability

    PubMed Central

    Ibbotson, Paul; Kearvell-White, Jennifer

    2015-01-01

    We present evidence that individual variation in grammatical ability can be predicted by individual variation in inhibitory control. We tested 81 5-year-olds using two classic tests from linguistics and psychology (Past Tense and the Stroop). Inhibitory control was a better predicator of grammatical ability than either vocabulary or age. Our explanation is that giving the correct response in both tests requires using a common cognitive capacity to inhibit unwanted competition. The implications are that understanding the developmental trajectory of language acquisition can benefit from integrating the developmental trajectory of non-linguistic faculties, such as executive control. PMID:26659926

  2. Strategies of Adaptive Ability Measurement.

    DTIC Science & Technology

    A number of strategies are described for adapting ability test items to individual differences in ability levels of testees. Each strategy consists of a different set of rules for selecting the sequence of test items to be administered to a given testee. Advantages and disadvantages of each strategy are discussed, and research issues unique to the strategy are described. Strategies reviewed are differentiated into two-stage approaches and multi-stage approaches. Several variations of the two-stage approach are described. The various

  3. The influence of water activity and temperature on germination, growth and sporulation of Stachybotrys chartarum strains.

    PubMed

    Frazer, Schale; Magan, Naresh; Aldred, David

    2011-07-01

    The objectives were to determine the influence of water activity (a(w), 0.997-0.92) and temperature (10-37°C) and their interactions on conidial germination, mycelial growth and sporulation of two strains of Stachybotrys chartarum in vitro on a potato dextrose medium. Studies were carried out by modifying the medium with glycerol and either spread plating with conidia to evaluate germination and germ tube extension or centrally inoculating treatment media for measuring mycelial growth rates and harvesting whole colonies for determining sporulation. Overall, germination of conidia was significantly influenced by a(w) and temperature and was fastest at 0.997-0.98 a(w) between 15 and 30°C with complete germination within 24 h. Germ tube extension was found to be most rapid at similar a(w) levels and 25-30°C. Mycelial growth rates of both strains were optimal at 0.997 a(w) between 25 and 30°C, with very little growth at 37°C. Sporulation was optimum at 30°C at 0.997 a(w). However, under drier conditions, this was optimum at 25°C. This shows that there are differences in the ranges of a(w) x temperature for germination and growth and for sporulation. This may help in understanding the role of this fungal species in damp buildings and conditions under which immune-compromised patients may be at risk when exposed to such contaminants in the indoor air environment.

  4. Learning Anatomy Enhances Spatial Ability

    ERIC Educational Resources Information Center

    Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Donders, A. R. T.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2013-01-01

    Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine ("n" = 242, intervention) and…

  5. Technology and Motor Ability Development

    ERIC Educational Resources Information Center

    Wang, Lin; Lang, Yong; Luo, Zhongmin

    2014-01-01

    As a new member joining the technology family, active video games have been developed to promote physical exercise. This working-in-progress paper shares an ongoing project on examining the basic motor abilities that are enhanced through participating in commercially available active video games. [For the full proceedings see ED557181.

  6. Cognitive Abilities of Maltreated Children

    ERIC Educational Resources Information Center

    Viezel, Kathleen D.; Freer, Benjamin D.; Lowell, Ari; Castillo, Jenean A.

    2015-01-01

    School psychologists should be aware of developmental risk factors for children who have been abused or neglected. The present study used the "Wechsler Intelligence Scale for Children, Fourth Edition" to examine the cognitive abilities of 120 children in foster care subsequent to maltreatment. Results indicated that, compared to a…

  7. Learning Anatomy Enhances Spatial Ability

    ERIC Educational Resources Information Center

    Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Donders, A. R. T.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2013-01-01

    Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine ("n" = 242, intervention) and…

  8. Test of Mathematical Abilities (TOMA).

    ERIC Educational Resources Information Center

    Howell, Kenneth W.

    1990-01-01

    The Test of Mathematical Abilities is used to identify students (ages 8-18) who are above or below age peers in 5 areas (attitude toward math, vocabulary, computation, general information, and story problems). This paper describes the test's administration, summation of data, standardization, reliability, and validity. (JDD)

  9. Challenging High-Ability Students

    ERIC Educational Resources Information Center

    Scager, Karin; Akkerman, Sanne F.; Pilot, Albert; Wubbels, Theo

    2014-01-01

    The existing literature on indicators of an optimal learning environment for high-ability students frequently discusses the concept of challenge. It is, however, not clear what, precisely, constitutes appropriate challenge for these students. In this study, the authors examined an undergraduate honours course, Advanced Cell Biology, which has…

  10. Ability Estimation for Conventional Tests.

    ERIC Educational Resources Information Center

    Kim, Jwa K.; Nicewander, W. Alan

    1993-01-01

    Bias, standard error, and reliability of five ability estimators were evaluated using Monte Carlo estimates of the unknown conditional means and variances of the estimators. Results indicate that estimates based on Bayesian modal, expected a posteriori, and weighted likelihood estimators were reasonably unbiased with relatively small standard…

  11. Ability Tests, Measurements, and Markets.

    ERIC Educational Resources Information Center

    Sternberg, Robert J.

    1992-01-01

    Progress, or lack thereof, in the development of ability testing is reviewed. Current tests, though inadequate, respond to the demands of test consumers. Test publishers must look ahead to changing demands and begin to lead the market, rather than follow it, by drawing on basic research in testing. (SLD)

  12. Emotional Intelligence and Leadership Abilities

    ERIC Educational Resources Information Center

    Herbst, H. H.; Maree, J. G.; Sibanda, E.

    2006-01-01

    While exceptional leaders share certain qualities like a strong personal ethic and a compelling vision of the future, research has failed to provide conclusive "proof" of the link between a leader's effectiveness and his/ her emotional intelligence (defined from a cognitive perspective, as a set of abilities). Given the increased…

  13. Cognitive Abilities of Maltreated Children

    ERIC Educational Resources Information Center

    Viezel, Kathleen D.; Freer, Benjamin D.; Lowell, Ari; Castillo, Jenean A.

    2015-01-01

    School psychologists should be aware of developmental risk factors for children who have been abused or neglected. The present study used the "Wechsler Intelligence Scale for Children, Fourth Edition" to examine the cognitive abilities of 120 children in foster care subsequent to maltreatment. Results indicated that, compared to a…

  14. Resettlement and Ability - One Community.

    ERIC Educational Resources Information Center

    Skanes, G. R.

    Since one aim of Newfoundland's resettlement program is to provide better schools and more highly qualified teachers, abilities of 152 children resettled at a reception center in Arnold's Cove were tested in 1971 to see if they differed from those of children native to the community. Tests used for students in grades 2-11 were the Standard…

  15. The Structure of Mathematical Ability.

    ERIC Educational Resources Information Center

    Furneaux, W. D.; Rees, Ruth

    1978-01-01

    A mathematics test and the Thurstone PMA Battery were administered to 225 technical students. The item/item correlations were analyzed using both a principal components and a maximum-likelihood method. After varimax rotation, the same structure emerged from both. Results suggest a "mathematical ability" factor independent of…

  16. Competence: Commodification of Human Ability

    ERIC Educational Resources Information Center

    Han, Soonghee

    2008-01-01

    The purpose of this article is to analyze the meaning and presumptions of competence in the concrete context of knowledge capitalism. First, the nature of competence as a "commodification of human ability" that obtains a standardized monetary value to sell in the labor market, is elucidated by applying Karl Marx's critical theory. Second, it is…

  17. Challenging High-Ability Students

    ERIC Educational Resources Information Center

    Scager, Karin; Akkerman, Sanne F.; Pilot, Albert; Wubbels, Theo

    2014-01-01

    The existing literature on indicators of an optimal learning environment for high-ability students frequently discusses the concept of challenge. It is, however, not clear what, precisely, constitutes appropriate challenge for these students. In this study, the authors examined an undergraduate honours course, Advanced Cell Biology, which has…

  18. Method To Enhance Growth and Sporulation of Pelletized Biocontrol Fungi †

    PubMed Central

    Knudsen, G. R.; Eschen, D. J.; Dandurand, L. M.; Wang, Z. G.

    1991-01-01

    The biocontrol fungi Trichoderma harzianum, used to control soilborne plant pathogens, and Beauveria bassiana, used to control insect pests, were formulated as mycelial biomass in alginate pellets with wheat bran added. After drying for 0, 4, or 16 h, pellets were placed in water or in aqueous solutions of polyethylene glycol (PEG) 8000 for 4 to 24 h and then allowed to continue drying. PEG-treated pellets containing T. harzianum showed significantly greater proliferation of hyphae in soil than untreated pellets or pellets treated with water. Production of conidia of T. harzianum from PEG-treated pellets was lower than production from untreated pellets after 4 days, although rates were equivalent after 7 days. In contrast, production of conidia of B. bassiana was significantly more rapid from PEG-treated pellets than from untreated pellets. Biocontrol of soilborne plant pathogens or insect pests may be enhanced by rapid hyphal growth of T. harzianum in soil or rapid sporulation of B. bassiana on foliage, respectively. Therefore, PEG treatment may improve the efficacy of these biocontrol agents. PMID:16348562

  19. Mutation of AREA affects growth, sporulation, nitrogen regulation, and pathogenicity in Colletotrichum gloeosporioides.

    PubMed

    Bi, Fangcheng; Ment, Dana; Luria, Neta; Meng, Xiangchun; Prusky, Dov

    2017-02-01

    The GATA transcription factor AreA is a global nitrogen regulator that restricts the utilization of complex and poor nitrogen sources in the presence of good nitrogen sources in microorganisms. In this study, we report the biological function of an AreA homolog (the CgareA gene) in the fruit postharvest pathogen Colletotrichum gloeosporioides. Targeted gene deletion mutants of areA exhibited significant reductions in vegetative growth, increases in conidia production, and slight decreases in conidial germination rates. Quantitative RT-PCR (qRT-PCR) analysis revealed that the expression of AreA was highly induced under nitrogen-limiting conditions. Moreover, compared to wild-type and complemented strains, nitrogen metabolism-related genes were misregulated in ΔareA mutant strains. Pathogenicity assays indicated that the virulence of ΔareA mutant strains were affected by the nitrogen content, but not the carbon content, of fruit hosts. Taken together, our results indicate that CgareA plays a critical role in fungal development, conidia production, regulation of nitrogen metabolism and virulence in Colletotrichum gloeosporioides.

  20. Ability and Mathematics: The Mindset Revolution that Is Reshaping Education

    ERIC Educational Resources Information Center

    Boaler, Jo

    2013-01-01

    Recent scientific evidence demonstrates both the incredible potential of the brain to grow and change and the powerful impact of growth mindset messages upon students' attainment. Schooling practices, however, particularly in England, are based upon notions of fixed ability thinking which limits students' attainment and increases inequality. This…

  1. Ability and Mathematics: The Mindset Revolution that Is Reshaping Education

    ERIC Educational Resources Information Center

    Boaler, Jo

    2013-01-01

    Recent scientific evidence demonstrates both the incredible potential of the brain to grow and change and the powerful impact of growth mindset messages upon students' attainment. Schooling practices, however, particularly in England, are based upon notions of fixed ability thinking which limits students' attainment and increases inequality. This…

  2. Elevated temperature crack growth

    NASA Technical Reports Server (NTRS)

    Kim, K. S.; Vanstone, R. H.

    1992-01-01

    The purpose of this program was to extend the work performed in the base program (CR 182247) into the regime of time-dependent crack growth under isothermal and thermal mechanical fatigue (TMF) loading, where creep deformation also influences the crack growth behavior. The investigation was performed in a two-year, six-task, combined experimental and analytical program. The path-independent integrals for application to time-dependent crack growth were critically reviewed. The crack growth was simulated using a finite element method. The path-independent integrals were computed from the results of finite-element analyses. The ability of these integrals to correlate experimental crack growth data were evaluated under various loading and temperature conditions. The results indicate that some of these integrals are viable parameters for crack growth prediction at elevated temperatures.

  3. Imagery Ability and Task Performance.

    DTIC Science & Technology

    1983-01-24

    size of the dots was varied to test visual * . acuity , the number of dots was varied to test the ability to maintain complex images, and the trajectory...REPORT NUMBER 12. GOVT ACCESSION NO. 3. RECIPIENT’S CATALOG NUMBER Technical Report #2 Ti b i / V Q/) _ 4. TITLE ( amd Subtitle) S. TYPE OF REPORT...Mental imagery Visual thinking Spatial reasoning . 20. ABSTRACT (Continue an reverse aide If necesery mid identify by block numtber) Kosslyn, Brunn

  4. Assessment of renal concentrating ability.

    PubMed Central

    Curtis, J R; Donovan, B A

    1979-01-01

    Maximum urine osmolality was measured during a 24-hour control period in normal ambulant and working subjects and hospital inpatients and compared with that achieved after intramuscular injection of 4 microgram desamino-cys-1-8-D-arginine vasopressin (DDAVP). Most of the normal subjects passed maximally concentrated urine at some time during the control period. The results suggest that in less active subjects or hospital inpatients the DDAVP test is a suitable method of assessing renal concentrating ability. PMID:421089

  5. [Vision and car driving ability].

    PubMed

    Wilhelm, Helmut

    2011-05-01

    Visual functions relevant for car driving are: Visual acuity, contrast and twilight vision, visual field, ocular motility and alignment and colour vision. Generally accepted and standardized tests are available for visual acuity and visual field. Maximum permissible values have been defined arbitrarily and are hardly supported by studies. European standards have been published comprising also contrast and twilight vision. When examining driving ability progressive and treatable ocular disorders such as cataract and glaucoma have to be considered.

  6. Measuring Multi-tasking Ability

    DTIC Science & Technology

    2003-07-01

    world MT ability or performance. Consideration of the cognitive operations most likely tapped by the PRP procedure reveal its probable limitations...including error, decreased morale, high training costs, high turnover rates, and attrition. This research shows that it is now possible to develop a...very nature, stressful. Hence, many jobs that require MT also have high turnover rates and attrition. These jobs often require extensive training

  7. Visual Discriminatory Ability Among Prereaders.

    ERIC Educational Resources Information Center

    Blair, John Raymond; Ryckman, David B.

    The ability of 50 lower middle-class and 25 upper middle-class prereading children to discriminate between pairs of uppercase alphabet letters was tested. A set of 3x5 cards with a sample stimulus in the upper center section of each card and two alternative choice stimuli just below and to the right and left of the sample was used. The 650 total…

  8. Implicit learning as an ability.

    PubMed

    Kaufman, Scott Barry; Deyoung, Colin G; Gray, Jeremy R; Jiménez, Luis; Brown, Jamie; Mackintosh, Nicholas

    2010-09-01

    The ability to automatically and implicitly detect complex and noisy regularities in the environment is a fundamental aspect of human cognition. Despite considerable interest in implicit processes, few researchers have conceptualized implicit learning as an ability with meaningful individual differences. Instead, various researchers (e.g., Reber, 1993; Stanovich, 2009) have suggested that individual differences in implicit learning are minimal relative to individual differences in explicit learning. In the current study of English 16-17year old students, we investigated the association of individual differences in implicit learning with a variety of cognitive and personality variables. Consistent with prior research and theorizing, implicit learning, as measured by a probabilistic sequence learning task, was more weakly related to psychometric intelligence than was explicit associative learning, and was unrelated to working memory. Structural equation modeling revealed that implicit learning was independently related to two components of psychometric intelligence: verbal analogical reasoning and processing speed. Implicit learning was also independently related to academic performance on two foreign language exams (French, German). Further, implicit learning was significantly associated with aspects of self-reported personality, including intuition, Openness to Experience, and impulsivity. We discuss the implications of implicit learning as an ability for dual-process theories of cognition, intelligence, personality, skill learning, complex cognition, and language acquisition.

  9. Stature and status: Height, ability, and labor market outcomes

    PubMed Central

    Case, Anne; Paxson, Christina

    2009-01-01

    The well-known association between height and earnings is often thought to reflect factors such as self esteem, social dominance, and discrimination. We offer a simpler explanation: height is positively associated with cognitive ability, which is rewarded in the labor market. Using data from the US and the UK, we show that taller children have higher average cognitive test scores, and that these test scores explain a large portion of the height premium in earnings. Children who have higher test scores also experience earlier adolescent growth spurts, so that height in adolescence serves as a marker of cognitive ability. PMID:19603086

  10. Growth hormone stimulation test (image)

    MedlinePlus

    ... test is usually performed to identify if hGH (human growth hormone) is deficient. The test is performed by administering the amino acid arginine in a vein to raise hGH levels. The test measures the ability of the pituitary to secrete growth hormone in ...

  11. Parkinson's disease and driving ability

    PubMed Central

    Singh, Rajiv; Pentland, Brian; Hunter, John; Provan, Frances

    2007-01-01

    Objectives To explore the driving problems associated with Parkinson's disease (PD) and to ascertain whether any clinical features or tests predict driver safety. Methods The driving ability of 154 individuals with PD referred to a driving assessment centre was determined by a combination of clinical tests, reaction times on a test rig and an in‐car driving test. Results The majority of cases (104, 66%) were able to continue driving although 46 individuals required an automatic transmission and 10 others needed car modifications. Ability to drive was predicted by the severity of physical disease, age, presence of other associated medical conditions, particularly dementia, duration of disease, brake reaction, time on a test rig and score on a driving test (all p<0.001). The level of drug treatment and the length of driving history were not correlated. Discriminant analysis revealed that the most important features in distinguishing safety to drive were severe physical disease (Hoehn and Yahr stage 3), reaction time, moderate disease associated with another medical condition and high score on car testing. Conclusions Most individuals with PD are safe to drive, although many benefit from car modifications or from using an automatic transmission. A combination of clinical tests and in‐car driving assessment will establish safety to drive, and a number of clinical correlates can be shown to predict the likely outcome and may assist in the decision process. This is the largest series of consecutive patients seen at a driving assessment centre reported to date, and the first to devise a scoring system for on‐road driving assessment. PMID:17178820

  12. Assessing Algebraic Solving Ability: A Theoretical Framework

    ERIC Educational Resources Information Center

    Lian, Lim Hooi; Yew, Wun Thiam

    2012-01-01

    Algebraic solving ability had been discussed by many educators and researchers. There exists no definite definition for algebraic solving ability as it can be viewed from different perspectives. In this paper, the nature of algebraic solving ability in terms of algebraic processes that demonstrate the ability in solving algebraic problem is…

  13. Aspergillus nidulans ChiA is a glycosylphosphatidylinositol (GPI)-anchored chitinase specifically localized at polarized growth sites.

    PubMed

    Yamazaki, Harutake; Tanaka, Aya; Kaneko, Jun-ichi; Ohta, Akinori; Horiuchi, Hiroyuki

    2008-06-01

    It is believed that chitinases play important physiological roles in filamentous fungi since chitin is one of the major cell wall components in these organisms. In this paper we investigated a chitinase gene, chiA, of Aspergillus nidulans and found that the gene product of chiA consists of a signal sequence, a region including chitinase consensus motifs, a Ser/Thr/Pro-rich region and a glycosylphosphatidylinositol (GPI)-anchor attachment motif. Phosphatidylinositol-specific phospholipase C treatment of the fusion protein of ChiA and enhanced green fluorescent protein (EGFP)-ChiA-EGFP-caused a change in its hydrophobicity, indicating that ChiA is a GPI-anchored protein. ChiA-EGFP localized at the germ tubes of conidia, at hyphal branching sites and hyphal tips. chiA expression was specifically high during conidia germination and in the marginal growth regions of colonies. These results suggest that ChiA functions as a GPI-anchored chitinase at the sites where cell wall remodeling and/or cell wall maturation actively take place.

  14. Growth Disorders

    MedlinePlus

    ... because their parents are. But some children have growth disorders. Growth disorders are problems that prevent children from developing ... or other features. Very slow or very fast growth can sometimes signal a gland problem or disease. ...

  15. Growth Problems

    MedlinePlus

    ... function and also play a role in growth. Hypothyroidism can cause slow growth because the thyroid gland ... to support normal growth. A major symptom of hypothyroidism is feeling tired or sluggish. A blood test ...

  16. Effects of Two Salts Compounds on Mycelial Growth, Sporulation, and Spore Germination of Six Isolates of Botrytis cinerea in the Western North of Algeria

    PubMed Central

    Boumaaza, Boualem; Benkhelifa, Mohamed; Belkhoudja, Moulay

    2015-01-01

    Six isolates of Botrytis cinerea were isolated from leaves and stems of different tomato varieties taken from four areas in the northwest of Algeria where tomato is mostly grown in greenhouses and high tunnels. The purpose of this research was to determine the effect of two salts, NaCl and CaCl2, on three stages of Botrytis cinerea's life cycle. All isolates tested were stimulated in 50 to 150 ppm; NaCl was the most effective treatment to increase mycelial growth at two tested concentrations. However, at 300 ppm concentration, CaCl2 completely inhibited the growth of mycelium; they reach 34.78% for the isolate TR46 and 26.72% for isolate F27. The sodium and calcium salts stimulated conidia production in liquid culture. We noticed that the effect of calcium chloride on sporulation was average while sodium chloride. In the medium containing 50 ppm, calcium chloride and sodium chloride increased the germination capacity of most isolates compared with the control. Other calcium salts, at 100 or 300 ppm, decreased the germination percentage of the conidia. With the exception of sodium salts, the inhibitions of germination reduce at 150 or 300 compared with the control. Conidial germination was slightly inhibited by sodium chloride only when the concentration was over 300 ppm. PMID:25883657

  17. Cardioprotective abilities of white wine.

    PubMed

    Cui, Jianhua; Tosaki, Arpad; Cordis, Gerald A; Bertelli, Alberto A E; Bertelli, Aldo; Maulik, Nilanjana; Das, Dipak K

    2002-05-01

    To study if white wines, like red wine, can also protect the heart from ischemia reperfusion injury, ethanol-free extracts of three different white wines (WW1, WW2 and WW3) (100 mg/100 g body weight) were given orally to Sprague Dawley rats (200 g body weight) for three weeks. Control rats were given water only for the same period of time. After three weeks, rats were anesthetized and sacrificed, and the hearts excised for the preparation of isolated working rat heart. All hearts were subjected to 30 min global ischemia followed by two hours of reperfusion. The results demonstrated that among the three different white wines, only WW2 showed cardioprotection as evidenced by improved post-ischemic ventricular recovery compared to control. The amount of malonaldehyde production in white wine-fed rat hearts were lower compared to that found in control hearts indicating reduced formation of the reactive oxygen species. In vitro studies using chemiluminescence technique revealed that these white wines scavenged both superoxide anions and hydroxyl radicals. The results of our study demonstrated that only WW2 white wine provided cardioprotection as evidenced by the improved the post-ischemic contractile recovery and reduced myocardial infarct size. The cardioprotective effect of this white wine may be attributed, at least in part, from its ability to function as an in vivo antioxidant.

  18. Cognitive processing of drawing abilities.

    PubMed

    Guérin, F; Ska, B; Belleville, S

    1999-08-01

    This critical review examines constructional apraxia from a cognitive neuropsychological perspective. To our knowledge, van Sommers (1989) is the only researcher to present a global cognitive model of drawing abilities. He organizes it into two hierarchical systems: Marr's model of visual perception and a graphic production system. The latter comprises four hierarchically organized components: depiction decisions, production strategy, contingent planning, and articulatory and economic constraints. Van Sommers' model will be discussed in light of other models and on the basis of empirical neuropsychological studies (Farah, 1984; Kosslyn & Koenig, 1992; Roncato, Sartori, Masterson, & Rumiati, 1987; van Sommers, 1989). We find that: (1) the Kosslyn and Koenig visual perception model describes more accurately the perceptual components underlying copying than the visual perception system of van Sommers' drawing model, (2) Van Sommers' arguments in favor of a depiction processing as opposed to visual imagery are not convincing, (3) Van Sommers' assumption that a production strategy is a component is unclear, and (4) articulatory and economic constraints are not cognitive components, but constraints imposed during action programming. This literature review leads to a discussion of future research topics and the specificity of constructional apraxia. Copyright 1999 Academic Press.

  19. Antibacterial ability and hemocompatibility of graphene functionalized germanium

    PubMed Central

    Geng, Hao; Dai, Jiayun; Li, Jinhua; Di, Zengfeng; Liu, Xuanyong

    2016-01-01

    Germanium (Ge), as an elemental semiconductor material, has been an attractive candidate for manufacturing semiconductor microelectronic device. In the present investigation, to improve the biocompatibility of Ge-based device, graphene film is directly deposited on the Ge surface with different coverage area by controlling the growth time. Compared to bare Ge, the presence of graphene film entitles Ge with satisfactory antibacterial ability against Staphylococcus aureus (S.aureus), and acceptable antibacterial ability against Escherichia coli (E. coli). Meanwhile, antibacterial efficiency closely correlates with coverage area of graphene film, and larger graphene coverage always leads to better antibacterial performance. The underlying mechanism is thought to be the integrative action of phospholipids disturbance and electron extraction at the interface between graphene and biomembrane. Meanwhile, the electron extraction action would further lead to the activation of platelet. This study might provide some new insights into the relationship between antibacterial ability and hemocompatibility based on graphene functionalized biomedical device. PMID:27876839

  20. Antibacterial ability and hemocompatibility of graphene functionalized germanium

    NASA Astrophysics Data System (ADS)

    Geng, Hao; Dai, Jiayun; Li, Jinhua; di, Zengfeng; Liu, Xuanyong

    2016-11-01

    Germanium (Ge), as an elemental semiconductor material, has been an attractive candidate for manufacturing semiconductor microelectronic device. In the present investigation, to improve the biocompatibility of Ge-based device, graphene film is directly deposited on the Ge surface with different coverage area by controlling the growth time. Compared to bare Ge, the presence of graphene film entitles Ge with satisfactory antibacterial ability against Staphylococcus aureus (S.aureus), and acceptable antibacterial ability against Escherichia coli (E. coli). Meanwhile, antibacterial efficiency closely correlates with coverage area of graphene film, and larger graphene coverage always leads to better antibacterial performance. The underlying mechanism is thought to be the integrative action of phospholipids disturbance and electron extraction at the interface between graphene and biomembrane. Meanwhile, the electron extraction action would further lead to the activation of platelet. This study might provide some new insights into the relationship between antibacterial ability and hemocompatibility based on graphene functionalized biomedical device.

  1. Resource capture and competitive ability of non-pathogenic Pseudogymnoascus spp. and P. destructans, the cause of white-nose syndrome in bats.

    PubMed

    Wilson, Michael B; Held, Benjamin W; Freiborg, Amanda H; Blanchette, Robert A; Salomon, Christine E

    2017-01-01

    White-nose syndrome (WNS) is a devastating fungal disease that has been causing the mass mortality of hibernating bats in North America since 2006 and is caused by the psychrophilic dermatophyte Pseudogymnoascus destructans. Infected bats shed conidia into hibernaculum sediments and surfaces, but it is unknown if P. destructans can form stable, reproductive populations outside its bat hosts. Previous studies have found non-pathogenic Pseudogymnoascus in bat hibernacula, and these fungi may provide insight into the natural history of P. destructans. We compared the relatedness, resource capture, and competitive ability of non-pathogenic Pseudogymnoascus isolates with P. destructans to determine if they have similar adaptations for survival in hibernacula sediment. All non-pathogenic Pseudogymnoascus isolates grew faster, utilized a broader range of substrates with higher efficiency, and were generally more resistant to antifungals compared to P. destructans. All isolates also showed the ability to displace P. destructans in co-culture assays, but only some produced extractible antifungal metabolites. These results suggest that P. destructans would perform poorly in the same environmental niche as non-pathogenic Pseudogymnoascus, and must have an alternative saprophytic survival strategy if it establishes active populations in hibernaculum sediment and non-host surfaces.

  2. Resource capture and competitive ability of non-pathogenic Pseudogymnoascus spp. and P. destructans, the cause of white-nose syndrome in bats

    PubMed Central

    Wilson, Michael B.; Held, Benjamin W.; Freiborg, Amanda H.; Blanchette, Robert A.

    2017-01-01

    White-nose syndrome (WNS) is a devastating fungal disease that has been causing the mass mortality of hibernating bats in North America since 2006 and is caused by the psychrophilic dermatophyte Pseudogymnoascus destructans. Infected bats shed conidia into hibernaculum sediments and surfaces, but it is unknown if P. destructans can form stable, reproductive populations outside its bat hosts. Previous studies have found non-pathogenic Pseudogymnoascus in bat hibernacula, and these fungi may provide insight into the natural history of P. destructans. We compared the relatedness, resource capture, and competitive ability of non-pathogenic Pseudogymnoascus isolates with P. destructans to determine if they have similar adaptations for survival in hibernacula sediment. All non-pathogenic Pseudogymnoascus isolates grew faster, utilized a broader range of substrates with higher efficiency, and were generally more resistant to antifungals compared to P. destructans. All isolates also showed the ability to displace P. destructans in co-culture assays, but only some produced extractible antifungal metabolites. These results suggest that P. destructans would perform poorly in the same environmental niche as non-pathogenic Pseudogymnoascus, and must have an alternative saprophytic survival strategy if it establishes active populations in hibernaculum sediment and non-host surfaces. PMID:28617823

  3. You Are What You Eat? Meal Type, Socio-Economic Status and Cognitive Ability in Childhood

    ERIC Educational Resources Information Center

    von Stumm, Sophie

    2012-01-01

    The current study tests if the type of children's daily main meal (slow versus fast food) mediates the association of socioeconomic status (SES) with cognitive ability and cognitive growth in childhood. A Scottish birth cohort (Growing Up in Scotland) was assessed at ages 3 (N = 4512) and 5 years (N = 3833) on cognitive ability (i.e. vocabulary…

  4. You Are What You Eat? Meal Type, Socio-Economic Status and Cognitive Ability in Childhood

    ERIC Educational Resources Information Center

    von Stumm, Sophie

    2012-01-01

    The current study tests if the type of children's daily main meal (slow versus fast food) mediates the association of socioeconomic status (SES) with cognitive ability and cognitive growth in childhood. A Scottish birth cohort (Growing Up in Scotland) was assessed at ages 3 (N = 4512) and 5 years (N = 3833) on cognitive ability (i.e. vocabulary…

  5. Influence of culture media and environmental factors on mycelial growth and sporulation of Lasiodiplodia theobromae (Pat.) Griffon and Maubl.

    PubMed

    Saha, A; Mandal, P; Dasgupta, S; Saha, D

    2008-05-01

    Lasiodiplodia theobromae, a common tea (Camellia sinensis) pathogen, usually does not sporulate or sporulates poorly in common media, which makes spore production difficult. In this study the effects of culture media, carbon source, nitrogen source, temperature, pH and light on mycelial growth and sporulation were evaluated. Among several carbon sources tested, glucose and sucrose were found superior for growth. Potassium nitrate supplemented media showed maximum growth amongst the tested inorganic nitrogen sources while peptone produced maximum growth among the tested organic nitrogen sources. Tea root extract supplemented potato dextrose agar medium was found to be the most suitable for mycelial growth and sporulation of L. theobromae. The fungus grow at temperatures ranging from 40 to 36 degrees C, with optimum growth at 28 degrees C and no growth was noted at 40 degrees C. There was no significant effect of different light period on growth of L. theobromae, but light enhanced sporulation. The fungus grow at pH 3.0-8.0 and optimum growth was observed at pH 6.0. Tea root extract supplemented potato dextrose agar medium with pH 6.0 was the most suitable for production of conidia of L. theobromae at 28 degrees C. Hence this media may be recommended for inoculum production for further studies.

  6. Inverse correlation of ability to produce aflatoxin and aspergillus colonization of maize seed

    USDA-ARS?s Scientific Manuscript database

    Seeds of aflatoxin-resistant and aflatoxin susceptible maize lines were inoculated with conidia of aflatoxin-producing Aspergillus flavus or A. parasiticus isolates or isogenic non-producing mutants. Conidial yields recovered from resistant maize seed after seven days were significantly lower for af...

  7. An empirical investigation on the forecasting ability of mallows model averaging in a macro economic environment

    NASA Astrophysics Data System (ADS)

    Yin, Yip Chee; Hock-Eam, Lim

    2012-09-01

    This paper investigates the forecasting ability of Mallows Model Averaging (MMA) by conducting an empirical analysis of five Asia countries, Malaysia, Thailand, Philippines, Indonesia and China's GDP growth rate. Results reveal that MMA has no noticeable differences in predictive ability compared to the general autoregressive fractional integrated moving average model (ARFIMA) and its predictive ability is sensitive to the effect of financial crisis. MMA could be an alternative forecasting method for samples without recent outliers such as financial crisis.

  8. Improvement of Speaking Ability through Interrelated Skills

    ERIC Educational Resources Information Center

    Liao, Guoqiang

    2009-01-01

    How to improve students' ability of speaking English? That is the key point we are concerned about. This paper discusses the possibility and necessity of improving students' ability by combining the four skills of speaking, listening, reading and writing.

  9. Autocrine growth factors and solid tumor malignancy.

    PubMed Central

    Walsh, J. H.; Karnes, W. E.; Cuttitta, F.; Walker, A.

    1991-01-01

    The ability of malignant cells to escape the constraint that normally regulate cell growth and differentiation has been a primary focus of attention for investigators of cancer cell biology. An outcome of this attention has been the discovery that the protein products of oncogenes play a role in the activation of growth signal pathways. A second outcome, possibly related to abnormal oncogene expression, has been the discovery that malignant cells frequently show an ability to regulate their own growth by the release of autocrine growth modulatory substances. Most important, the growth of certain malignant cell types has been shown to depend on autocrine growth circuits. A malignant tumor whose continued growth depends on the release of an autocrine growth factor may be vulnerable to treatment with specific receptor antagonists or immunoneutralizing antibodies designed to break the autocrine circuit. Information is rapidly emerging concerning autocrine growth factors in selected human solid tissue malignancy. Images PMID:1926844

  10. A microscopy study of hyphal growth of Penicillium rubens on gypsum under dynamic humidity conditions.

    PubMed

    van Laarhoven, Karel A; Huinink, Hendrik P; Adan, Olaf C G

    2016-05-01

    To remediate indoor fungal growth, understanding the moisture relations of common indoor fungi is crucial. Indoor moisture conditions are commonly quantified by the relative humidity (RH). RH is a major determinant of the availability of water in porous indoor surfaces that fungi grow on. The influence of steady-state RH on growth is well understood. Typically, however, the indoor RH constantly changes so that fungi have to endure frequent periods of alternating low and high RH. Knowledge of how common indoor fungi survive and are affected by the low-RH periods is limited. In particular, the specific effects of a drop in RH on the growth of the mycelium remain unclear. In this work, video microscopy was used to monitor hyphal growth of Penicillium rubens on gypsum substrates under controlled dynamic humidity conditions. The effect of a single period of low RH (RH = 50-90%) interrupting favourable conditions (RH = 97%) was tested. It was found that hyphal tips ceased to extend when exposed to any tested decrease in RH. However, new hyphal growth always emerges, seemingly from the old mycelium, suggesting that this indoor fungus does not rely only on conidia to survive the humidity patterns considered. These findings are a fundamental step in unravelling the effect of RH on indoor fungal growth.

  11. Explaining High Abilities of Nobel Laureates

    ERIC Educational Resources Information Center

    Shavinina, Larisa

    2004-01-01

    Although the Nobel Prize is associated with a rare, superior degree of intellectually creative achievement, high abilities of Nobel laureates are far from well explained. This paper argues that Nobel laureates' high abilities are determined in part by their extracognitive abilities, that is, specific feelings, preferences, beliefs and intuitive…

  12. Predicting Academic Achievement with Cognitive Ability

    ERIC Educational Resources Information Center

    Rohde, Treena Eileen; Thompson, Lee Anne

    2007-01-01

    The purpose of the present study is to explain variation in academic achievement with general cognitive ability and specific cognitive abilities. Grade point average, Wide Range Achievement Test III scores, and SAT scores represented academic achievement. The specific cognitive abilities of interest were: working memory, processing speed, and…

  13. Explaining High Abilities of Nobel Laureates

    ERIC Educational Resources Information Center

    Shavinina, Larisa

    2004-01-01

    Although the Nobel Prize is associated with a rare, superior degree of intellectually creative achievement, high abilities of Nobel laureates are far from well explained. This paper argues that Nobel laureates' high abilities are determined in part by their extracognitive abilities, that is, specific feelings, preferences, beliefs and intuitive…

  14. The Stratified Adaptive Computerized Ability Test.

    ERIC Educational Resources Information Center

    Weiss, David J.

    This report describes the stratified adaptive (stradaptive) test as a strategy for tailoring an ability test to individual differences in testee ability; administration of the test is controlled by a time-shared computer system. The rationale of this method is described as it derives from Binet's strategy of ability test administration and…

  15. Innovative Allies: Spatial and Creative Abilities

    ERIC Educational Resources Information Center

    Coxon, Steve V.

    2012-01-01

    Spatial and creative abilities are important for innovations in science, technology, engineering, and math (STEM) fields, but talents are rarely developed from these abilities by schools, including among gifted children and adolescents who have a high potential to become STEM innovators. This article provides an overview of each ability and makes…

  16. The Gendering of Abilities in Senior PE

    ERIC Educational Resources Information Center

    Hay, Peter J.; Macdonald, Doune

    2010-01-01

    Background: Ability is a foundational concept in education. For example, one's perspective of the nature of ability influences how one conceives of the educability and achievement potential of students. However, ability has generally been under-theorised in physical education (PE), particularly in relation to gender. Moreover, default assumptions…

  17. Predicting Academic Achievement with Cognitive Ability

    ERIC Educational Resources Information Center

    Rohde, Treena Eileen; Thompson, Lee Anne

    2007-01-01

    The purpose of the present study is to explain variation in academic achievement with general cognitive ability and specific cognitive abilities. Grade point average, Wide Range Achievement Test III scores, and SAT scores represented academic achievement. The specific cognitive abilities of interest were: working memory, processing speed, and…

  18. Urine concentrating and diluting ability during aging.

    PubMed

    Sands, Jeff M

    2012-12-01

    Urine concentrating ability is reduced during normal aging in people and rats. The abundance of many of the key transport proteins that contribute to urine concentrating ability is reduced in the kidney medulla of aged rats. The reductions in water, sodium, and urea transport protein abundances, and their reduced response to water restriction, contribute to the reduced ability of aged rats to concentrate their urine and conserve water. If similar mechanisms occur in human kidneys, it would provide a molecular explanation for the reduced urine concentrating ability in aging and may provide opportunities for novel therapeutic approaches to improve urine concentrating ability and/or nocturnal polyuria.

  19. A qualitative approach to assessing work ability.

    PubMed

    Tengland, Per-Anders

    2013-01-01

    We often need to be able to assess the extent to which individuals have or lack work ability. For this we need instruments. Most of the instruments available have flaws. They either lack validity or they use roundabout methods when collecting information about the individual's work ability. The aim of this paper is to present a conceptual model for constructing a questionnaire that can be used for assessing work ability. The methods used are philosophical, i.e. analytical and deductive. A conceptual theory is provided, and based on the resulting definition of the concept of "work ability" conclusions are drawn regarding how to assess work ability. When constructing quantitative instruments, we can increase validity through using a more strict definition of work ability. However, such an approach will only solve some of the problems noted above. The proposal is, instead, to create a qualitative questionnaire, founded on a definition of "work ability", which focuses on the concrete problems concerning the work ability of the individual. Finally, a sketch of such an instrument is provided, with questions covering all the relevant aspects of work ability. The qualitative questionnaire proposed is believed to be superior to more traditional (quantitative) instruments for assessing a person's work ability, as well as for finding solutions to her problems concerning work ability.

  20. Differentiation of Cognitive Abilities across the Lifespan

    PubMed Central

    Tucker-Drob, Elliot M.

    2009-01-01

    Existing representations of cognitive ability structure are exclusively based on linear patterns of interrelations. However, a number of developmental and cognitive theories predict that abilities are differentially related across ages (age differentiation-dedifferentiation) and across levels of functioning (ability differentiation). Nonlinear factor analytic models were applied to multivariate cognitive ability data from 6,273 individuals, ages 4 to 101 years, who were selected to be nationally representative of the United States population. Results consistently supported ability differentiation, but were less clear with respect to age differentiation-dedifferentiation. Little evidence for age modification of ability differentiation was found. These findings are particularly informative about the nature of individual differences in cognition, and the developmental course of cognitive ability level and structure. PMID:19586182

  1. Face recognition: a model specific ability

    PubMed Central

    Wilmer, Jeremy B.; Germine, Laura T.; Nakayama, Ken

    2014-01-01

    In our everyday lives, we view it as a matter of course that different people are good at different things. It can be surprising, in this context, to learn that most of what is known about cognitive ability variation across individuals concerns the broadest of all cognitive abilities; an ability referred to as general intelligence, general mental ability, or just g. In contrast, our knowledge of specific abilities, those that correlate little with g, is severely constrained. Here, we draw upon our experience investigating an exceptionally specific ability, face recognition, to make the case that many specific abilities could easily have been missed. In making this case, we derive key insights from earlier false starts in the measurement of face recognition’s variation across individuals, and we highlight the convergence of factors that enabled the recent discovery that this variation is specific. We propose that the case of face recognition ability illustrates a set of tools and perspectives that could accelerate fruitful work on specific cognitive abilities. By revealing relatively independent dimensions of human ability, such work would enhance our capacity to understand the uniqueness of individual minds. PMID:25346673

  2. Face recognition: a model specific ability.

    PubMed

    Wilmer, Jeremy B; Germine, Laura T; Nakayama, Ken

    2014-01-01

    In our everyday lives, we view it as a matter of course that different people are good at different things. It can be surprising, in this context, to learn that most of what is known about cognitive ability variation across individuals concerns the broadest of all cognitive abilities; an ability referred to as general intelligence, general mental ability, or just g. In contrast, our knowledge of specific abilities, those that correlate little with g, is severely constrained. Here, we draw upon our experience investigating an exceptionally specific ability, face recognition, to make the case that many specific abilities could easily have been missed. In making this case, we derive key insights from earlier false starts in the measurement of face recognition's variation across individuals, and we highlight the convergence of factors that enabled the recent discovery that this variation is specific. We propose that the case of face recognition ability illustrates a set of tools and perspectives that could accelerate fruitful work on specific cognitive abilities. By revealing relatively independent dimensions of human ability, such work would enhance our capacity to understand the uniqueness of individual minds.

  3. Self-Care Ability in Hemodialysis Patients

    PubMed Central

    Atashpeikar, Soulmaz; Jalilazar, Tahereh; Heidarzadeh, Mehdi

    2012-01-01

    Introduction: Considering the numerous physical and psychological problems in hemo-dialysis patients, they are dependent on others in some daily activities and in fact, they do not have full self-care ability. A few studies have ever been done, particularly in Iran, on self-care ability of hemodialysis patients. The present study aimed to determine self-care ability of these patients in addition to evaluate its association with some demo-graphic characteristics. Methods: This was a descriptive study in 2009 done in Marag-heh, Bonab and Miandoab Hospitals. The study population included 115 hemodialysis patients who were eligible. Data were collected using a combined and modified ques-tionnaire including demographic characteristics and self-care ability items. Results: Self-care ability was desirable in 78.3 percent of the patients. The highest desirable self-care ability in the study participants was related to vascular access (73%) and the highest undesirable self-care ability was related to follow the diet. There was a significant asso-ciation between self-care ability and some demographic characteristics including age, gender, marital status and employment status. Conclusion: Hemodialysis patients did not have full self-care ability. It is necessary to enhance their knowledge about diet, complications of hemodialysis and preventive methods through accurate and permanent education so that they can increase their self-care ability. PMID:25276673

  4. Graphic Abilities in Relation to Mathematical and Scientific Ability in Adolescents

    ERIC Educational Resources Information Center

    Stavridou, Fotini; Kakana, Domna

    2008-01-01

    Background: The study investigated a small range of cognitive abilities, related to visual-spatial intelligence, in adolescents. This specific range of cognitive abilities was termed "graphic abilities" and defined as a range of abilities to visualise and think in three dimensions, originating in the domain of visual-spatial…

  5. Elevated temperature crack growth

    NASA Technical Reports Server (NTRS)

    Kim, K. S.; Vanstone, R. H.

    1989-01-01

    Alloy 718 crack growth experiments were conducted to assess the ability of the selected path-independent (P-I) integrals to describe the elevated temperature crack growth behavior. These tests were performed on single edge notch (SEN) specimens under displacement control with multiple extensometers to monitor the specimen and crack mouth opening displacement (CMOD). The displacements in these tests were sufficiently high to induce bulk cyclic inelastic deformation of the specimen. Under these conditions, the linear elastic fracture mechanics (LEFM) parameter K does not correlate the crack growth data. The experimentally measured displacement gradients at the end of specimen gage length were used as the boundary conditions in elastic-plastic finite element method (FEM) analyses. These analyses were performed with a node release approach using CYANIDE, a GEAE FEM code, which included a gap element which is capable of efficiently simulating crack closure. Excellent correlation was obtained between the experimentally measured and predicted variation of stress and CMOD with crack length and the stress-CMOD loops for Alloy 718 tests conducted at 538 C. This confirmed the accuracy of the FEM crack growth simulation approach. The experimentally measured crack growth rate data correlated well the selected P-I integrals. These investigations have produced significant progress in developing P-I integrals as non-linear fracture mechanics parameters. The results suggest that this methodology has the potential of accurately describing elevated temperature crack growth behavior under the combined influence of thermal cycling and bulk elastic-inelastic deformation states.

  6. The relationship between comprehension and metacomprehension ability.

    PubMed

    Maki, R H; Jonas, D; Kallod, M

    1994-03-01

    We investigated the relationship between the ability to comprehend text and the ability to predict future performance and to assess past performance on text. Subjects were poor at predicting performance, which may be why prediction accuracy did not relate to measures of comprehension ability. Measures of comprehension ability did relate to the accuracy with which subjects assessed their performance on tests. Better and faster comprehenders judged their relative levels of test performance over sections of text more accurately than did poorer and slower comprehenders.

  7. Assessment of Learning Abilities Using Rate Measures,

    DTIC Science & Technology

    Military psychology, *Learning, *Rates, Mental ability, Measurement, Information processing, Computer applications, Performance(Human), Aptitude tests, Perception( Psychology ), Research management, Symposia

  8. The elementary school teachers’ ability in the length measurement

    NASA Astrophysics Data System (ADS)

    Julie, Hongki

    2017-09-01

    The purpose of this study was to describe the elementary school teachers' mathematical ability (1) to develop students’ activities which constructed longer than, shorter than, and as long as concepts, (2) to develop students’ activities which constructed standard unit on the length measurement, and (3) to develop a problem which used by student to construct why a conversion activity on the unit of the length was useful in the daily life after they have participated in the Realistic Mathematics Education (RME) workshops. Curry and Outhread said if teachers knew more about the growth of students’ conceptual understanding of the length, they would be better able to teach that topic [4]. Therefore, in the workshop, teachers were asked to learn more on the stages of the measurement teaching and learning process and why each stage was important. This capability was described by the results of a test which was content of four problems given to teachers after they have attended the workshop. Research subjects in this study were 14 elementary school teachers at Yogyakarta. The results of the study were as follows: (1) only four of 14 teachers who had the first ability; (2) all teachers had the second ability; and (3) all the teachers did not have the third ability.

  9. Bilingual Children’s Language Abilities and Early Reading Outcomes in Head Start and Kindergarten

    PubMed Central

    Hammer, Carol Scheffner; Lawrence, Frank R.; Miccio, Adele W.

    2012-01-01

    Purpose The purpose of this study was to investigate the relationship between Head Start children’s receptive language development and their kindergarten reading outcomes. Method Eighty-eight bilingual children who were eligible to attend Head Start for 2 years participated in the study. Growth curve models were used to examine the relationship between children’s language abilities during 2 years in Head Start and end-of-kindergarten reading outcomes. Results The results revealed that children’s English and Spanish receptive language abilities increased during Head Start, and children’s early reading abilities in English were within the typical range of monolingual norms at the end of kindergarten. Children’s early reading abilities in Spanish were nearly 1 SD below the test mean or lower. The results also showed that children’s growth in their English and Spanish language abilities during Head Start predicted their early reading abilities in English and Spanish. Implications The findings imply that preschool programs are needed that target children’s growth in language and not their performance measured at a particular point in time. Also, the results demonstrate the importance of early and regular evaluation of bilingual children’s development in both languages in order to monitor children’s growth in their two languages. PMID:17625050

  10. Sex Differences in Spatial Ability: A Critique.

    ERIC Educational Resources Information Center

    Clear, Sarah-Jane

    1978-01-01

    Explores (1) problems of the validity of tests of spatial ability, and (2) problems of the recessive gene influence theory of the origin of sex differences in spatial ability. Studies of cognitive strategies in spatial problem solving are suggested as a way to further investigate recessive gene influence. (Author/RH)

  11. High Ability Students' Voice on Learning Motivation

    ERIC Educational Resources Information Center

    Garn, Alex C.; Jolly, Jennifer L.

    2014-01-01

    This study used a self-determination theory lens to investigate high ability learners' motivational experiences. Participants were 15 high ability youth involved in a summer learning camp for gifted students. Two major themes emerged from qualitative data analysis: (a) "The Fun Factor of Learning" and (b) "The Rewards and Pressures…

  12. Improvisation as Ability, Culture, and Experience

    ERIC Educational Resources Information Center

    Higgins, Lee; Mantie, Roger

    2013-01-01

    We argue in this article for greater role for improvisation in the music classroom. Based on an extensive examination of scholarship about improvisational practices, we propose three conceptualizations--ability, culture, experience--that can serve to guide the teaching of improvisation. When considered as an "ability," improvisation is a…

  13. Contour Line Portraits: Excited about Artistic Abilities

    ERIC Educational Resources Information Center

    Neal, Kari Gertz

    2012-01-01

    In this article, the author describes a self-portrait project that encouraged students, boosted their self-confidence, and got them excited about their artistic abilities--while producing amazing results. This lesson effectively develops artistic ability by compelling students to see that drawing is quite simply breaking down objects into the…

  14. Sex Differences in Spatial Ability: A Critique.

    ERIC Educational Resources Information Center

    Clear, Sarah-Jane

    1978-01-01

    Explores (1) problems of the validity of tests of spatial ability, and (2) problems of the recessive gene influence theory of the origin of sex differences in spatial ability. Studies of cognitive strategies in spatial problem solving are suggested as a way to further investigate recessive gene influence. (Author/RH)

  15. General Mental Ability: From Psychometrics to Biology.

    ERIC Educational Resources Information Center

    Jensen, Arthur R.

    1991-01-01

    This paper summarizes empirical findings of research on a theory of general mental ability, based on laboratory studies of the relationship between measurements of individual differences on conventional psychometric tests and in speed and efficiency of information processes. The paper covers characteristics of "g" (general mental ability),…

  16. Work Ability of Finnish Physical Education Teachers

    ERIC Educational Resources Information Center

    Mäkelä, Kasper; Hirvensalo, Mirja

    2015-01-01

    In the physical education (PE) teachers' profession, physical tasks comprise a large part of the job. PE teachers identify their health as good, and they are satisfied with their job. Nevertheless, the work ability of PE teachers may be decreasing. Purpose: The purpose of this article was to explore the work ability of Finnish PE teachers. What…

  17. Improving Learning Ability Through Compensatory Physical Education.

    ERIC Educational Resources Information Center

    Humphrey, James H.

    This book presents a procedure for improving, through the medium of physical education activities, the learning ability of children. Rather than using systematic exercises for the correction of certain perceptual-motor deficiencies, learning ability can be enhanced through active games, rhythmic activities, and self-testing activities. Covering a…

  18. About Assessment Criteria of Driver's Accidental Abilities

    ERIC Educational Resources Information Center

    Lobanova, Yuliya I.; Glushko, Kirill V.

    2016-01-01

    The article points at the importance of studying the human factor as a cause of accidents of drivers, especially in loosely structured traffic situations. The description of the experiment on the measurement of driver's accidental abilities is given. Under accidental ability is meant the capability to ensure the security of driving as a behavior…

  19. Highlights from "Research on Ability Grouping."

    ERIC Educational Resources Information Center

    Kulik, Chen-Lin C.; Kulik, James A.

    1982-01-01

    THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: Except for high-ability students in honors classes, ability grouping has little significant effect on learning outcomes, student attitudes toward subject matter and school, and self-concept. The differences that are found in grouped classes are all positive, however slight, and there is no evidence…

  20. Psycholinguistic Abilities of Children with Williams Syndrome

    ERIC Educational Resources Information Center

    Rossi, Natalia F.; Heinze, Elena Garayzabal; Giacheti, Celia M.; Goncalves, Oscar F.; Sampaio, Adriana

    2012-01-01

    The objective of this study was to investigate the psycholinguistic abilities of children with Williams syndrome (WS) and typically developing children using the Illinois Test of Psycholinguistic Abilities (ITPA). Performance on the ITPA was analysed in a group with WS (N=20, mean age=8.5 years, SD=1.62) and two typically developing groups,…

  1. The Learning Effect of Modeling Ability Instruction

    ERIC Educational Resources Information Center

    Chang, Shu-Nu

    2008-01-01

    To achieve the goal of scientific literacy, besides conveying science and technology concepts, cultivating students' modeling ability has become important. However, in-service teachers face the difficulty that their teaching load increases while they are still bound by limited teaching hours. Teachers may know of modeling ability, life related…

  2. Assessing Social Ability in Online Learning Environments

    ERIC Educational Resources Information Center

    Laffey, James; Lin, Guan Yu; Lin, Yimei

    2006-01-01

    Education is a social practice and the ability to interact socially is important to social cognitive learning and social learning. Online education is frequently criticized because it lacks social interaction, a sense of social engagement, and the benefits of learning with others. Social ability with computer-mediated social mechanisms is key to…

  3. Mental Rotation Ability and Computer Game Experience

    ERIC Educational Resources Information Center

    Gecu, Zeynep; Cagiltay, Kursat

    2015-01-01

    Computer games, which are currently very popular among students, can affect different cognitive abilities. The purpose of the present study is to examine undergraduate students' experiences and preferences in playing computer games as well as their mental rotation abilities. A total of 163 undergraduate students participated. The results showed a…

  4. IRT Models for Ability-Based Guessing

    ERIC Educational Resources Information Center

    Martin, Ernesto San; del Pino, Guido; De Boeck, Paul

    2006-01-01

    An ability-based guessing model is formulated and applied to several data sets regarding educational tests in language and in mathematics. The formulation of the model is such that the probability of a correct guess does not only depend on the item but also on the ability of the individual, weighted with a general discrimination parameter. By so…

  5. Cognitive Style: Ability and Preference Components.

    ERIC Educational Resources Information Center

    Gray, Jerry L.

    This study investigates the preference and ability components of cognitive style as measured by a verbal test for fifth-grade children. Performances from an intellectual ability test, a pictorial cognitive style test, and school achievement tests were included as construct validity variables. The results supported conclusions drawn by Robinson and…

  6. IRT Models for Ability-Based Guessing

    ERIC Educational Resources Information Center

    Martin, Ernesto San; del Pino, Guido; De Boeck, Paul

    2006-01-01

    An ability-based guessing model is formulated and applied to several data sets regarding educational tests in language and in mathematics. The formulation of the model is such that the probability of a correct guess does not only depend on the item but also on the ability of the individual, weighted with a general discrimination parameter. By so…

  7. High Ability Students' Voice on Learning Motivation

    ERIC Educational Resources Information Center

    Garn, Alex C.; Jolly, Jennifer L.

    2014-01-01

    This study used a self-determination theory lens to investigate high ability learners' motivational experiences. Participants were 15 high ability youth involved in a summer learning camp for gifted students. Two major themes emerged from qualitative data analysis: (a) "The Fun Factor of Learning" and (b) "The Rewards and Pressures…

  8. Adolescents' Conceptions of Ability and Intelligence.

    ERIC Educational Resources Information Center

    Nicholls, John G.

    Adolescents' developing sense of competence is based on two domains, ability and intelligence. Intelligence testing generally presumes a conception of ability as current capacity that limits the extent to which effort can improve performance. Conceptions of intelligence, and other skills, involve implications about the nature of different forms of…

  9. Cultural Studies, Pedagogy, and Response-Ability

    ERIC Educational Resources Information Center

    Rossiter, Penelope

    2012-01-01

    A few years ago, in a tutorial in an advanced level undergraduate subject that she teaches--"Emotions, Culture and Community"--the author was a witness and participant in a pedagogical event that moved and provoked the class: It incited response-ability. This article is about that event, the meaning of response-ability, and the window…

  10. Spatial Ability Learning through Educational Robotics

    ERIC Educational Resources Information Center

    Julià, Carme; Antolí, Juan Òscar

    2016-01-01

    Several authors insist on the importance of students' acquisition of spatial abilities and visualization in order to have academic success in areas such as science, technology or engineering. This paper proposes to discuss and analyse the use of educational robotics to develop spatial abilities in 12 year old students. First of all, a course to…

  11. Mental Rotation Ability and Computer Game Experience

    ERIC Educational Resources Information Center

    Gecu, Zeynep; Cagiltay, Kursat

    2015-01-01

    Computer games, which are currently very popular among students, can affect different cognitive abilities. The purpose of the present study is to examine undergraduate students' experiences and preferences in playing computer games as well as their mental rotation abilities. A total of 163 undergraduate students participated. The results showed a…

  12. Work Ability of Finnish Physical Education Teachers

    ERIC Educational Resources Information Center

    Mäkelä, Kasper; Hirvensalo, Mirja

    2015-01-01

    In the physical education (PE) teachers' profession, physical tasks comprise a large part of the job. PE teachers identify their health as good, and they are satisfied with their job. Nevertheless, the work ability of PE teachers may be decreasing. Purpose: The purpose of this article was to explore the work ability of Finnish PE teachers. What…

  13. Improving Learning Ability Through Compensatory Physical Education.

    ERIC Educational Resources Information Center

    Humphrey, James H.

    This book presents a procedure for improving, through the medium of physical education activities, the learning ability of children. Rather than using systematic exercises for the correction of certain perceptual-motor deficiencies, learning ability can be enhanced through active games, rhythmic activities, and self-testing activities. Covering a…

  14. Contour Line Portraits: Excited about Artistic Abilities

    ERIC Educational Resources Information Center

    Neal, Kari Gertz

    2012-01-01

    In this article, the author describes a self-portrait project that encouraged students, boosted their self-confidence, and got them excited about their artistic abilities--while producing amazing results. This lesson effectively develops artistic ability by compelling students to see that drawing is quite simply breaking down objects into the…

  15. 45 CFR 1616.7 - Language ability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Language ability. 1616.7 Section 1616.7 Public... § 1616.7 Language ability. In areas where a significant number of clients speak a language other than English as their principal language, a recipient shall adopt employment policies that insure that legal...

  16. Does Classmate Ability Influence Students' Social Skills?

    ERIC Educational Resources Information Center

    Gottfried, Michael A.

    2015-01-01

    Empirically, the link between classmate ability and individual-level student achievement has been established. And yet, within the scope of this body of literature, there is a dearth of studies examining if a relationship also persists between classmate ability and non-achievement outcomes--that is, social skills. This article fills this research…

  17. Reading Abilities and Strategies: A Short Introduction

    ERIC Educational Resources Information Center

    Liu, Feng

    2010-01-01

    This paper gives a short analysis of reading abilities and reading strategies. Much research has been done to investigate the nature of reading, though it's had to exactly define reading abilities and strategies. Different kinds of readings are discussed in this paper and distinctions are made between first language reading and second or foreign…

  18. Spatial Ability Learning through Educational Robotics

    ERIC Educational Resources Information Center

    Julià, Carme; Antolí, Juan Òscar

    2016-01-01

    Several authors insist on the importance of students' acquisition of spatial abilities and visualization in order to have academic success in areas such as science, technology or engineering. This paper proposes to discuss and analyse the use of educational robotics to develop spatial abilities in 12 year old students. First of all, a course to…

  19. Verbal Ability, Argument Order, and Attitude Formation

    PubMed Central

    Mozuraitis, Mindaugas; Chambers, Craig G.; Daneman, Meredyth

    2016-01-01

    The current study explored the interaction of verbal ability and presentation order on readers’ attitude formation when presented with two-sided arguments. Participants read arguments for and against compulsory voting and genetic engineering, and attitudes were assessed before and after reading the passages. Participants’ verbal ability was measured, combining vocabulary knowledge and reading comprehension skill. Results suggested that low verbal-ability participants were more persuaded by the most recent set of arguments whereas high verbal-ability participants formed attitudes independent of presentation order. Contrary to previous literature, individual differences in the personality trait need for cognition did not interact with presentation order. The results suggest that verbal ability is an important moderator of the effect of presentation order when formulating opinions from complex prose. PMID:27703437

  20. Verbal Ability, Argument Order, and Attitude Formation.

    PubMed

    Mozuraitis, Mindaugas; Chambers, Craig G; Daneman, Meredyth

    2016-01-01

    The current study explored the interaction of verbal ability and presentation order on readers' attitude formation when presented with two-sided arguments. Participants read arguments for and against compulsory voting and genetic engineering, and attitudes were assessed before and after reading the passages. Participants' verbal ability was measured, combining vocabulary knowledge and reading comprehension skill. Results suggested that low verbal-ability participants were more persuaded by the most recent set of arguments whereas high verbal-ability participants formed attitudes independent of presentation order. Contrary to previous literature, individual differences in the personality trait need for cognition did not interact with presentation order. The results suggest that verbal ability is an important moderator of the effect of presentation order when formulating opinions from complex prose.