Evaluation of elevator shafts as a pathway for fungal spores and particles to enter a hospital housing immuno-compromised patients

Background. It is estimated that hospitals spend between 28 and 33 billion dollars per year as a result of hospital-acquired infections. (Scott, 2009) The costs continue to rise despite the guidance and controls provided by hospital infection control staff to reduce patient exposures to fungal spores and other infectious agents. With all processes and controls in place, the vented elevator shaft represents an unprotected opening from the top of the building to the lower floors. The hypothesis for this prospective study is that there is a positive correlation between the number of Penicillium/Aspergillus-like spores, Cladosporium, ascospores, basidiospores in spores/m3 as individual spore categories found in the hoistway vent of an elevator shaft and the levels of the same spores, sampled near-simultaneously in the outdoor intake of the elevator shaft. Specific aims of this study include determining if external Penicillium/Aspergillus-like spores are entering the healthcare facility via the elevator shaft and hoistway vents. Additional aims include determining levels of Penicillium/Aspergillus-like spores outdoors, in the elevator shafts, and indoors in areas possibly affected by elevator shaft air; and, finally, to evaluate whether any effect is observed due to the installation of a hoistway vent damper, installed serendipitously during this study. ^ Methods. Between April 2010 and September 2010, a total of 3,521 air samples were collected, including 363 spore trap samples analyzed microscopically for seven spore types, and polymerase chain reaction analyses on 254 air samples. 2178 particle count measurements, 363 temperature readings and 363 relative humidity readings were also obtained from 7 different locations potentially related to the path of air travel inside and near a centrally-located and representative elevator shaft. ^ Results. Mean Penicillium/Aspergillus-like spore values were higher outside the building (530 spores/m3 of air) than inside the hoistway (22.8 spores/m3) during the six month study. Mean values inside the hospital were lower than outside throughout the study, ranging from 15 to 73 spores/m3 of air. Mean Penicillium/Aspergillus-like spore counts inside the hoistway decreased from 40.1 spores/m3 of air to 9 spores/m3 of air following the installation of a back draft damper between the outside air and the elevator shaft. Comparison of samples collected outside the building and inside the hoistway vent prior to installing the damper indicated a strong positive correlation (Spearman's Rho=0.8008, p=0.0001). The similar comparison following the damper installation indicated a moderate non-significant inverse correlation (Spearman's rho = −0.2795, p=0.1347). ^ Conclusion. Elevator shafts are one pathway for mold spores to enter a healthcare facility. A significant correlation was detected between spores and particle counts inside the hoistway and outside prior to changes in the ventilation system. The insertion of the back draft damper appeared to lower the spore counts inside the hoistway and inside the building. The mold spore counts in air outside the study building were higher in the period following the damper installation while the levels inside the hoistway and hospital decreased. Cladosporium and Penicillium/Aspergillus -like spores provided a method for evaluating indoor air quality as a natural tracer from outside the building to inside the building. Ascospores and basidiospores were not a valuable tracer due to low levels of detection during this study. ^ Installation of a back draft damper provides additional protection for the indoor environment of a hospital or healthcare facility, including in particular patients who may be immunocompromised. Current design standards and references do not require the installation of a back draft damper, but evaluation of adding language to relevant building codes should be considered. The data indicate a reduction in levels of Penicillium/Aspergillus -like spores, particle counts and a reduction in relative humidity inside of the elevator shaft after damper installation.^

NOVEL INDUCERS OF GLIOTOXIN PRODUCTION IN ASPERGILLUS FUMIGATUS

Secondary metabolites are produced by numerous organisms and can either be benign to humans or harmful. Genes involved in the synthesis and transport of these secondary metabolites are frequently found in gene clusters, which are often located in subtelomeric regions of the chromosome. These clusters are often coordinately regulated, being almost exclusively dependent on transcription factors that are located within the clusters themselves. Secondary metabolites are also regulated by a variety of factors, including nutritional factors, environmental factors and developmental processes. Gliotoxin, which is produced by a variety of Aspergillus species, Trichoderma species, and Penicillium species, exhibits immunosuppressive properties and has therefore been the subject of research for many laboratories. There have been a few proteins shown to regulate the gliotoxin cluster, most notably GliZ, a Zn2Cys6 binuclear finger transcription factor that lies within the cluster, and LaeA, a putative methyltransferase that globally regulates secondary metabolism clusters within numerous fungal organisms, although no study has demonstrated the direct binding of any protein to a promoter region in the gliotoxin cluster. I report here two novel proteins, GipA, a C2H2 transcription factor and GipB, a hybrid sensor kinase, which are involved in regulating the gliotoxin biosynthetic cluster. GipA plays an important role in gliotoxin production, as high-copy expression of gipA induces gliotoxin biosynthesis and loss of gipA reduces gliotoxin biosynthesis by 50%. GipB is also involved in regulating gliotoxin production, as high-copy expression of gipB induces gliotoxin biosynthesis, but only during certain stages of asexual development. Furthermore, loss of gipB reduces gliotoxin biosynthesis by 10%. Based on data obtained from this project, I propose a model for the regulation of gliA, the efflux pump of the gliotoxin cluster, which involves GipB signaling through both GliZ and GipA. I propose that GliZ and GipA are interdependent, as mutation of the GipA DNA binding site in the gliA promoter negatively affects both GliZ-mediated and GipA-mediated induction of gliA. This is further supported by the fact that GliZ cannot fully induce gliA in the absence of GipA and vice versa. This is the first time that anyone has shown evidence of a protein directly binding to the gliotoxin cluster. Even though biosynthetic clusters are often coordinately regulated, my model raises the possibility that gliA is independently regulated, as the layout of the binding site in the gliA promoter is not present upstream of any other genes in the gliotoxin cluster, except for gliZ.

Proceedings of the Nineteenth Annual Biochemical Engineering Symposium

The nineteenth symposium was held at the University of Missouri–Columbia on April 22, 1989. A total of eighteen papers were scheduled for presentation, of which nine were in poster session. Finally, fifteen papers were presented and sixteen were submitted for this proceedings. It was attended by 53 participants from five institutions. A sixth group (from Colorado State University) was kept from attending the symposium due to mechanical problems on the road and we missed them. Since they worked hard at their presentations, I requested CSU-group to submit their papers for the proceedings and I am happy that they did. ContentsMathematical modelling of a flour milling system. K. Takahashi, Y. Chen, J. Hosokoschi, and L. T. Fan. Kansas State University A novel solution to the problem of plasmid segregation in continuous bacterial fermentations. K.L. Henry, R. H. Davis, and A. L. Taylor. University of Colorado Modelling of embryonic growth in avian and reptile Eggs. C.L. Krause, R. C. Seagrave, and R. A. Ackerman. Iowa State University Mathematical modeling of in situ biodegradation processes. J.C. Wu, L. T. Fan, and L. E. Erickson. Kansas State University Effect of molecular changes on starch viscosity. C.H. Rosane and V. G. Murphy. Colorado State University Analysis of two stage recombinant bacterial fermentations using a structured kinetic model. F. Miao and D. S. Kampala. University of Colorado Lactic acid fermentation from enzyme-thinned starch by Lactobacillus amylovorus. P.S. Cheng, E. L. Iannotti, R. K. Bajpai, R. Mueller, and s. Yaeger. University of Missouri–Columbia Solubilization of preoxidized Texas lignite by cell-free broths of Penicillium strains. R. Moolick, M. N. Karim, J. C. Linden, and B. L. Burback. Colorado State University Separation of proteins from polyelectrolytes by ultrafiltration. A.G. Bazzano and C. E. Glatz. Iowa State University Growth estimation and modelling of Rhizopus oligosporus in solid state fermentations. D.-H. Ryoo, V. G. Murphy, M. N. Karim, and R. P. Tengerdy. Colorado State University Simulation of ethanol fermentations from sugars in cheese whey. C.J. Wang and R. K. Bajpai. University of Missouri–Columbia Studies on protoplast fusion of B. licheniformis. B. Shi, Kansas State University Cell separations of non-dividing and dividing yeasts using an inclined settler. C.-Y. Lee, R. H. Davis, and R. A. Sclafani. University of Colorado Effect of·serum upon local hydrodynamics within an airlift column. G.T. Jones, L. E. Erickson, and L. A. Glasgow. Kansas State University Optimization of heterologous protein secretion in continuous culture. A. Chatterjee, W. F. Remirez, and R. H. Davis. University of Colorado An improved model for lactic acid fermentation. P. Yeh, R. K. Bajpai, and E. L. Iannotti. University of Missouri–Columbia

Método de evaluación a campo de la resistencia al moho azul en clones de ajo tipo colorado

Con el objeto de ajustar un método de evaluación a campo para facilitar la selección de clones de ajo (Allium sativum L.) con resistencia a Penicillium allii, se realizó un ensayo replicado en el cual se midió la respuesta de tres clones experimentales a la infección, en dos épocas de plantación. Los tratamientos incluyeron combinaciones de presencia o ausencia de: a) desinfección de la "semilla", b) heridas artificiales en los bulbillos, c) inoculación artificial. Los bulbillos con la hoja envolvente se desinfectaron con una solución diluida de hipoclorito de sodio. La inoculación se realizó mediante la inmersión en una solución de 106 esporas•ml-1. Las heridas se realizaron con una lanceta (blood lancet). Los bulbillos se incubaron en cámara húmeda durante 24 horas a 20 °C, antes de plantación. Las variables respuestas computadas fueron las siguientes: número de plantas muertas, y vivas con síntomas y sin síntomas, a los 152 días de plantación en la primera época y 118 días en la segunda; número de bulbos por calibres y rendimiento a cosecha. La información obtenida se analizó a través de correspondencia simple, diferencia de proporciones y análisis paramétricos. Se detectaron mayores diferencias entre los tratamientos en la tasa de sobrevivencia y en la proporción de calibres comerciales en la época tardía. No se observaron diferencias (p < 0,05) del rendimiento en la plantación temprana. La herida fue determinante en el ingreso del patógeno. Los tratamientos quedaron limitados a un testigo: desinfectado, no inoculado y sin herida, y a un tratamiento: desinfectado, con inoculación y herida. Con respecto a la época, resultó conveniente la evaluación en plantaciones tardías porque se expresan mejor las diferencias entre los tratamientos.

Efecto del momento de cosecha sobre la calidad hortícola del topinambur (Helianthus tuberosus L.) conservado en cámara frigorífica

El interés por el cultivo de Topinambur (Helianthus tuberosus L.) es creciente a nivel mundial. Como toda hortaliza que se lleva al mercado, o se utiliza como materia prima para la industria, debe estar disponible a lo largo de todo el año. Por esto es importante desarrollar sistemas de almacenamiento que permitan conservar la calidad del producto el mayor tiempo posible. Existen muy pocos antecedentes sobre la conservación poscosecha de tubérculos de topinambur y las variaciones de calidad, que sufre el producto. A través del trabajo de tesis se buscó generar antecedentes sobre los efectos de la fecha de cosecha y la variedad de topinambur sobre las diferentes variables de calidad; la evolución de cada tratamiento conservado en cámara frigorífica y el efecto del lugar/condiciones (cámara frigorífica – campo) y tiempo de conservación sobre la calidad de los tubérculos. Se utilizaron dos variedades de topinambur (tubérculos rojos y blancos). Las variables respuesta ensayadas para definir atributos de calidad fueron: materia seca, sólidos solubles, firmeza, índice de color de piel y de pulpa, presencia de brotes, desarrollo de Penicillium y evolución del peso fresco. Se detectó que el período de cosecha, para garantizar la calidad de los tubérculos y buena evolución en cámara frigorífica durante todo el año, no debería extenderse más allá de los 49 días desde la ocurrencia de la primera helada para la zona de estudio, no observándose diferencias entre variedades. Para consumo en fresco se puede cosechar hasta el 98 días luego de la primera helada, pero estos tubérculos no se conservan correctamente en cámara frigorífica.

Experiment on marine fungus Microascus brevicaulis strain

The marine fungus Microascus brevicaulis strain LF580 is a non-model secondary metabolite producer with high yields of the two secondary metabolites scopularide A and B, which exhibit distinct activities against tumour cell lines. A mutant strain was obtained using UV mutagenesis, showing besides higher production levels faster growth and differences in pellet formation. Comparative proteomics were applied to gain deeper understanding of the regulation of production and of the physiology of this fungus and its mutant. For this purpose, an optimised protein extraction protocol was established. Here, we show the first proteome study of a marine fungus. In total, 4759 proteins were identified. The central metabolic pathway of LF580 could be mapped by using KEGG pathway analysis and GO annotation. Using iTRAQ labelling, 318 proteins were shown to be significantly regulated in the mutant strain: 189 were down- and 129 upregulated. Proteomics are a powerful tool for the understanding of regulatory aspects: The differences on proteome level could be attributed to a limited nutrient availability in wild type strain due to a strong pellet formation. This information can be applied to optimisation on strain and process level. The linkage between nutrient limitation and pellet formation in the non-model fungus M. brevicaulis is in consensus with the knowledge on model organisms like Aspergillus niger and Penicillium chrysogenum.

Determinación de la capacidad parasitaria de la microbiota fúngica y de sus extractos acuosos en las semillas de cardo (Cynara cardunculus L.)

El presente estudio evalúa el efecto que 6 diferentes géneros hongos aislados a partir de semillas de 54 diferentes cultivares de cardo y sus extractos acuosos tienen sobre la germinación y nascencia de las semillas. Se han realizado pruebas de patogenicidad con dos aislados de cada uno de los seis géneros de mayor frecuencia del inventario (Aspergillus, Penicillium, Fusarium, Rhizopus, Cladosporium y Alternaria), así como de los extractos producidos tras 3, 7 y 11 días de incubación de los micetos. Los resultados de las inoculaciones con los micetos muestran efectos negativos sobre los porcentajes de germinación, con reducciones en la germinación que fueron máximas tras las inoculaciones con Rhizopus stolonifer (29% de disminución) y Fusarium verticillioides (23%). Los porcentajes de emergencia disminuyen tras duplicar la concentración del inóculo, aumentando además drásticamente el número de plántulas dañadas sobre el total de las emergidas. En el significativo caso de la inoculación con Cladosporium la duplicación del inóculo disminuyó la germinación hasta en un 31% respecto al testigo. Las plántulas emergidas tras las inoculaciones con los extractos obtenidos a partir de cultivos líquidos de los hongos ensayados presentaban los mismos síntomas de atrofias y daños sobre raíz y coleóptilo que los descritos para cada hongo. Los extractos acuosos de los géneros estudiados disminuyen también la germinación. Los resultados nos muestran la diferente capacidad parasitaria de cada una de las especies estudiadas apreciándose además diferencias según los diferentes periodos de agitación de los hongos y permiten asegurar que la producción de toxinas está regulada por el hongo, y que no aumenta linealmente con el crecimiento miceliar.

Biogeografía de especies de Fusarium en el litoral mediterráneo de España

El trabajo presentado estudia la presencia de Fusarium oxysporum, F.solani(sensulato), F. equiseti y F.acuminatum en puntos del litoral de Almería, Alicante, Gerona e Islas Baleares (Menorca, Ibiza, Espalmador). Se analizaron tanto arenas de las playas (zonas intermareal y supramareal) como fondos marino situados a 27,9 y 7,2 metros de profundidad en Almería y a 10 m de profundidad en las Islas Baleares. Exceptuando el litoral de Gerona, en el resto de los enclaves se presentaron varias especies de Fusarium que se aislaron de las arenas de las playas, confirmando así resultados obtenidos con anterioridad. Lo más novedoso fue encontrar especies de Fusarium a diferentes profundidades marinas. En Almería F.oxysporum y F.equisti se aislaron a 27,9 y7,2 m profundidad. F. acuminatum se aisló de la muetra recogida a 27m de profundidad. En las islas Baleares, a10m de profundidad, se aislaron F. oxysporum, F. solani (sensulato), F.equiseti y F.acuminatum. El efecto antrópico, el comportamiento como "airborne" o los arrastres de aguas por las ramblas y torrentes podría explicar la presencia de estas especies en los hábitats mencionados. La permanencia de estas especies en los hábitats mencionados, especialmente en la zona intermareal de las playas y en los fondos marinos donde soportan elevadas presiones osmóticas por la alta salinidad del agua del mar Mediterráneo, permitirá estudios específicos sobre el comportamiento de estos hongos en medios muy salinos. Otros hongos aislados de arenas de playa y fondos marinos fueron: Acremonium, Alternaria, Aspergillus, Cladosporium, Dreschlera, Gliocladium Humicola, Penicillium, Phialophora, Rhizopus, Stemphylium, Trichoderma, Trichocladium y Ulocladium. Muchos de ellos fueron aislados del fondo marino, testimoniando así que estos hábitats no son exclusivos de Fusarium.

Evaluación de la patogeneicidad de la microbiota fúngica asociada a cinco variedades autóctonas españolas de judión (Phaseolus coccineus L.)

Se caracterizó la micoflora presente en las semillas de 5 cultivares de judión (Phaseolus coccineus L.) procedentes de una explotación dedicada a la agricultura ecológica de Oteruelo del Valle (Parque natural de Rascafría, Madrid) y de 5 variedades incluidas en el Catálogo Común de variedades Comerciales de la Unión Europea. Se analizaron un total de 3200 semillas de todos los lotes cosechadas en la campaña 2005-2006. Para ello se colocaron 5 semillas de cada muestra en placas de Petri con medio agar de patata glucosado (PDA) y 6 semillas por muestra en cámara húmeda, realizándose 20 repeticiones en cada caso, analizándose de esta manera al menos 220 semillas por muestra. Para conocer la presencia del género Fusarium se realizaron análisis específicos con todas las muestras, utilizando para ello medio selectivo para Fusarium realizándose lecturas periódicas y anotando el número de especies presentes en cada semilla. Se identificaron un total de 11 especies fúngicas diferentes. la presencia de los diferentes géneros varió entre los cultivares estudiados, siendo mucho menor, aunque no ausente en las semillas comerciales. Entre la microbiota fúngica aislada cabe destacar, por su potencial patogeneicidd o por su capacidad para la producción de micotoxinas o metabolitos secundarios, especies de los géneros Aspergillus, Alternaria o Rhizoctonia. En una segunda parte del estudio se evaluó el efecto que dichos hongos tienen sobre la germinación y nascencia de las semillas, realizándose pruebas de patogeneicidad sobre un total de 200 semillas de Phaseolus vulgaris variedad Calgary. Las inoculaciones se realizaron con cada uno de los dos aislados de los seis géneros de mayor importancia cuantitativa del inventario(Aspergillus, Penicillium Ulocladium, Rhizopus, Cladosporium y Alternaria) Los resultados de las inoculaciones muestran efectos negativos sobre los porcentajes de germinación en todos los tratamientos estudiados y muestran la diferente capacidad parasitaria de cada una de las especies estudiadas sobre Phaseolus vulgaris.

Biofouling of crypts of historical and architectural interest at la Plata Cemetery (Argentina)

Cemeteries are part of the cultural heritage of urban communities, containing funerary crypts and monuments of historical and architectural interest. Efforts aimed at the conservation of these structures must target not only the abiotic stresses that cause their destruction, such as light and humidity, but also biofouling by biotic agents. The purpose of this study was to assess the development of biofouling of several historically and architecturally valuable crypts at La Plata Cemetery (Argentina). Samples obtained from the biofilms, lichens, and fungal colonies that had developed on the marble surfaces and cement mortar of these crypts were analyzed by conventional microbiological techniques and by scanning electron microscopy. The lichens were identified as Caloplaca austrocitrina, Lecanora albescens, Xanthoparmelia farinosa and Xanthoria candelaria, the fungi as Aspergillus sp., Penicillium sp., Fusarium sp., Candida sp. and Rhodotorula sp., and the bacteria as Bacillus sp. and Pseudomonas sp. The mechanisms by which these microorganisms cause the aesthetic and biochemical deterioration of the crypts are discussed.

Effect of solute and matric potential on growth rate of fungal species isolated from cheese

The effect of water potential ( J w ) on the growth of 15 fungal species isolated from cheeses was analysed. The species, identified mainly by analysis of DNA sequences, belonged to genera Penicillium , Geotrichum , Mucor , Aspergillus , Microascus and Talaromyces . Particularly, the effect of matric potential ( J m ), and ionic (NaCl) and non-ionic (glycerol) solute potentials ( J s ) on growth rate was studied. The response of strains was highly dependent on the type of J w . For J s , clear profiles for optimal, permissive and marginal conditions for growth were obtained, and differences in growth rate were achieved comparing NaCl and glycerol for most of the species. Conversely, a sustained growth was obtained for J m in all the strains, with the exception of Aspergillus pseudoglaucus , whose growth increased proportionally to the level of water stress. Our results might help to understand the impact of environmental factors on the ecophysiology and dynamics of fungal populations associated to cheeses.

In vitro evaluation of commercial fibrolytic enzymes for improving the nutritive value of low-quality forages.

The aim of this work was to assess the effects of four doses of three commercial fibrolytic enzymes on ruminal fermentation of rice straw, maize stover and Pennisetum purpureum clon Cuba CT115 hay in batch cultures of ruminal micro-organisms from sheep. One enzyme was produced by Penicillium funiculosum (PEN) and two were from Trichoderma longibrachiatum (TL1 and TL2). Each liquid enzyme was diluted 200 (D1), 100 (D2), 50 (D3) and 10 (D4) - fold and applied to each substrate in quadruplicate over time and incubated for 120 h in rumen fluid. The D4 dose of each enzyme increased (P<0.05) the fractional rate of gas production and organic matter effective degradability for all substrates, and TL2 had similar effects when applied at D3. In 9 h incubations, PEN at D4, TL1 at all tested doses, and TL2 at D2, D3 and D4 increased (P<0.05) volatile fatty acid production and dry matter degradability for all substrates. The commercial enzymes tested were effective at increasing in vitro ruminal fermentation of low-quality forages, although effective doses varied with the enzyme.

Fungal biodeterioration of colour cinematographic films of the cultural heritage of Cuba

Until recently, cinematographic film was largely cellulose-triacetate-based. However, this material is highly susceptible to biodeterioration, thus placing historic film collections, an important part of the cultural heritage of many countries, at risk. In the present study, samples taken from several biodeteriorated color cinematographic films belonging to the collection of the Cuban Institute for Cinematographic Industry and Arts (ICAIC) were investigated. Infrared spectroscopy showed that all films were of the same composition, i.e., a gelatin emulsion coating one side of a cellulose-triacetate-based film support. The films were analyzed by environmental scanning electron microscopy and scanning electron microscopy to determine the degree of biodeterioration and the type of colonizing microorganisms. Significant fungal colonization was found on both sides of the films in all samples, with a higher concentration of fungi on the gelatin emulsion side. Epifluorescence microscopy of fluorochrome-dyed films demonstrated that some of the fungi were still active, indicating that the films under study, and probably others at the ICAIC, are at risk of further deterioration. Fungi were identified by molecular biology techniques. The fungi mainly responsible for the observed biodeterioration were those belonging to the genera Aspergillus and Cladosporium, although other genera, such as Microascus and Penicillium, were identified as well. In accordance with the findings described herein, the existing guidelines for the prevention and control of film biodeterioration are discussed.

Occurrence of moulds associated with ovine raw milk and cheeses of the Spanish region of Castilla La Mancha

The distribution of mould species was examined at several points of the processing chain in a Manchego cheese plant and associated dairy farms. Geotrichum and Fusarium were the most frequent genera isolated in milk samples as well as in 1-month ripened cheeses, evidencing a direct transfer from raw milk. Conversely, the mycobiota of long-ripened cheeses consisted mainly of Penicillium species, which gained entry to the cheese through the air of ripening rooms. This study contributes to the understanding of the dynamics of fungal populations in semihard and hard cheeses, highlighting that airborne transfer from the stables could have a direct impact on their quality.

Effect of solute and matric potential on growth rate of fungal species isolated from cheese

The effect of water potential ( J w ) on the growth of 15 fungal species isolated from cheeses was analysed. The species, identi fi ed mainly by analysis of DNA sequences, belonged to genera Penicillium, Geotrichum, Mucor , Aspergillus , Microascus and Talaromyces . Particularly, the effect of matric potential ( J m ), and ionic (NaCl) and non-ionic (glycerol) solute potentials ( J s ) on growth rate was studied. The response of strains was highly dependent on the type of J w . For J s, clear profiles for optimal, permissive and marginal conditions for growth were obtained, and differences in growth rate were achieved comparing NaCl and glycerol for most of the species. Conversely, a sustained growth was obtained for J m in all the strains, with the exception of Aspergillus pseudoglaucus, whose growth increased proportionally to the level of water stress. Our results might help to understand the impact of environmental factors on the ecophysiology and dynamics of fungal populations associated to cheeses.