Freeman, Jules S; Potts, Brad M; Vaillancourt, René E
Foliar fungal pathogens from the genus Mycosphaerella affect eucalyptus in natural forests and plantations worldwide. QTL analysis was conducted to dissect the genetic control of resistance in Eucalyptus globulus to a natural infection by Mycosphaerella leaf disease, using a clonally replicated outbred F2 family (112 genotypes) planted in a field trial. Two major QTL, with high LOD support (20.2 and 10.9) and high genomewide significance, explained a large proportion (52%) of the phenotypic variance in the severity of damage by Mycosphaerella cryptica, which may be indicative of oligogenic control. Both QTL were validated in a second F2 family and one was validated in a third F2 family. The mean values of different genotype classes at both major QTL argue for Mendelian inheritance with resistance dominant over susceptibility. There were strong correlations between the levels of Mycosphaerella damage in related genetic material planted in three widely separated locations in Tasmania. These findings together provide evidence that the genes controlling resistance to Mycosphaerella damage are stable in different genetic backgrounds and across different environments.
Benedict, Kaitlin; Park, Benjamin J
The link between natural disasters and subsequent fungal infections in disaster-affected persons has been increasingly recognized. Fungal respiratory conditions associated with disasters include coccidioidomycosis, and fungi are among several organisms that can cause near-drowning pneumonia. Wound contamination with organic matter can lead to post-disaster skin and soft tissue fungal infections, notably mucormycosis. The role of climate change in the environmental growth, distribution, and dispersal mechanisms of pathogenic fungi is not fully understood; however, ongoing climate change could lead to increased disaster-associated fungal infections. Fungal infections are an often-overlooked clinical and public health issue, and increased awareness by health care providers, public health professionals, and community members regarding disaster-associated fungal infections is needed.
Mattern, Derek J.; Valiante, Vito; Unkles, Shiela E.; Brakhage, Axel A.
Synthetic biology is an ever-expanding field in science, also encompassing the research area of fungal natural product (NP) discovery and production. Until now, different aspects of synthetic biology have been covered in fungal NP studies from the manipulation of different regulatory elements and heterologous expression of biosynthetic pathways to the engineering of different multidomain biosynthetic enzymes such as polyketide synthases or non-ribosomal peptide synthetases. The following review will cover some of the exemplary studies of synthetic biology in filamentous fungi showing the capacity of these eukaryotes to be used as model organisms in the field. From the vast array of different NPs produced to the ease for genetic manipulation, filamentous fungi have proven to be an invaluable source for the further development of synthetic biology tools. PMID:26284053
de Garín, A.; Figuerola, P.; Basualdo, A.; Giavedoni, P.; Oricchio, P.; Skansy, M.
The occurrence of fungal diseases is closely linked to specific atmospheric conditions affecting the life cycle of the fungus. Popular beliefs as well as scientific knowledge are in agreement on the effect of high temperature and moisture on fungal epidemics. The presence of a film of water on a plant, during an uninterrupted number of threshold hours is in many cases a necessary, and sometimes sufficient condition for fungal infection to develop. In this paper, we present a method to estimate the sequence of hours of wet and dry vegetal surface. Conventional hourly meteorological data are used. The accuracy of this method has been studied over an ideal sunflower field located in Balcarce (Buenos Aires, Argentina) with promising results.
Lim, Fang Yun; Keller, Nancy P
Despite their oftentimes-elusive ecological role, fungal natural products have, for better or worse, impacted our daily lives tremendously owing to their diverse and potent bioactive properties. This Janus-faced nature of fungal natural products inevitably ushered in a field of research dedicated towards understanding the ecology, organisms, genes, enzymes, and biosynthetic pathways that give rise to this arsenal of diverse and complex chemistry. Ongoing research in fungal secondary metabolism has not only increased our appreciation for fungal natural products as an asset but also sheds light on the pivotal role that these once-regarded "metabolic wastes" play in fungal biology, defense, and stress response in addition to their potential contributions towards human mycoses. Full orchestration of secondary metabolism requires not only the seamless coordination between temporal and spatial control of SM-associated machineries (e.g. enzymes, cofactors, intermediates, and end-products) but also integration of these machineries into primary metabolic processes and established cellular mechanisms. An intriguing, but little known aspect of microbial natural product synthesis lies in the spatial organization of both pathway intermediates and enzymes responsible for the production of these compounds. In this highlight, we summarize some major breakthroughs in understanding the genes and regulation of fungal natural product synthesis and introduce the current state of knowledge on the spatial and temporal control of fungal natural product synthesis.
Ravigné, Virginie; Lemesle, Valérie; Walter, Alicia; Mailleret, Ludovic; Hamelin, Frédéric M
Fungal plant parasites represent a growing concern for biodiversity and food security. Most ascomycete species are capable of producing different types of infectious spores both asexually and sexually. Yet the contributions of both types of spores to epidemiological dynamics have still to been fully researched. Here we studied the effect of mate limitation in parasites which perform both sexual and asexual reproduction in the same host. Since mate limitation implies positive density dependence at low population density, we modeled the dynamics of such species with both density-dependent (sexual) and density-independent (asexual) transmission rates. A first simple SIR model incorporating these two types of transmission from the infected compartment, suggested that combining sexual and asexual spore production can generate persistently cyclic epidemics in a significant part of the parameter space. It was then confirmed that cyclic persistence could occur in realistic situations by parameterizing a more detailed model fitting the biology of the Black Sigatoka disease of banana, for which literature data are available. We discuss the implications of these results for research on and management of Sigatoka diseases of banana.
Bruhn, Christian Anders Wathne
Molecular evolution of pathogenic viruses with RNA based genomes is most often fast enough to leave an informative genomic sequence signal within a timeframe that is relevant for the study of both recent and on-‐going epidemics (and epizootics). The true power of molecular evolutionary methodolo...
Bruhn, Christian Anders Wathne
Molecular evolution of pathogenic viruses with RNA based genomes is most often fast enough to leave an informative genomic sequence signal within a timeframe that is relevant for the study of both recent and on-‐going epidemics (and epizootics). The true power of molecular evolutionary methodolo...... be termed a modern synthesis of infectious disease epidemiology. The present work can be seen as an advocate of moving towards such a completely integrative approach....
Anggriani, N.; Putri, L. Nurul; Supriatna, A. K.
Many plants could not escape from diseases caused by fungi. The use of fungicide can help to reduce the spread of the fungi but if it used continuously with the same dosage, the fungi would be invulnerable to fungicide eventually. Hence, it is critical to know the appropriate level of fungicide application and its impact on the dynamics of the plants. In this paper we use an explicit model of fungal outbreaks of plant by taking into account a curative factor including the dynamic of fungicides itself. Granting of fungicide on crops is useful to control the infected plants as well as protecting the vulnerable plants. Optimal control is used to find out how many doses of the appropriate fungicide should be used to cure infected plants. Optimal control is obtained by applying Pontryagin's Minimum Principle. We found that the presence of appropriate level of fungicide speeds up the reduction of infected plants as well as accelerates the growth of healthy plants.
Andersen, B.; Frisvad, Jens Christian
Fresh tomatoes, homegrown and from supermarkets, with developing fungal lesions were collected. Each lesion was sampled, and the resulting fungal cultures were identified morphologically, and extracted for analyzes of secondary metabolites. The tomatoes were incubated at 25 degreesC for a week....... extracted, and analyzed for fungal metabolites. Extracts from pure cultures were compared with extracts from the moldy tomatoes and fungal metabolite standards in two HPLC systems with DAD and FLD detection. The results showed that Penicillium tularense, Stemphylium eturmiunum. and S. cf. lycopersici were...
Andersen, B.; Frisvad, Jens Christian
Fresh tomatoes, homegrown and from supermarkets, with developing fungal lesions were collected. Each lesion was sampled, and the resulting fungal cultures were identified morphologically, and extracted for analyzes of secondary metabolites. The tomatoes were incubated at 25 degreesC for a week. e...
Mapari, Sameer Shamsuddin; Thrane, Ulf; Meyer, Anne S.
The recent approval of fungal carotenoids as food colorants by the European Union has strengthened the prospects for fungal cell factories for the production of polyketide pigments. Fungal production of colorants has the main advantage of making the manufacturer independent of the seasonal supply...... of raw materials, thus minimizing batch-to-batch variations. Here, we review the potential of polyketide pigments produced from chemotaxonomically selected non-toxigenic fungal strains (e.g. Penicillium and Epicoccum spp.) to serve as food colorants. We argue that the production of polyketide azaphilone...... pigments from such potentially safe hosts is advantageous over traditional processes that involve Monascus spp., which risks co-production of the mycotoxin citrinin. Thus, there is tremendous potential for the development of robust fungal production systems for polyketide pigments, both to tailor...
Garin, Guillaume; Fournier, Christian; Andrieu, Bruno; Houlès, Vianney; Robert, Corinne; Pradal, Christophe
Sustainable agriculture requires the identification of new, environmentally responsible strategies of crop protection. Modelling of pathosystems can allow a better understanding of the major interactions inside these dynamic systems and may lead to innovative protection strategies. In particular, functional-structural plant models (FSPMs) have been identified as a means to optimize the use of architecture-related traits. A current limitation lies in the inherent complexity of this type of modelling, and thus the purpose of this paper is to provide a framework to both extend and simplify the modelling of pathosystems using FSPMs. Different entities and interactions occurring in pathosystems were formalized in a conceptual model. A framework based on these concepts was then implemented within the open-source OpenAlea modelling platform, using the platform's general strategy of modelling plant-environment interactions and extending it to handle plant interactions with pathogens. New developments include a generic data structure for representing lesions and dispersal units, and a series of generic protocols to communicate with objects representing the canopy and its microenvironment in the OpenAlea platform. Another development is the addition of a library of elementary models involved in pathosystem modelling. Several plant and physical models are already available in OpenAlea and can be combined in models of pathosystems using this framework approach. Two contrasting pathosystems are implemented using the framework and illustrate its generic utility. Simulations demonstrate the framework's ability to simulate multiscaled interactions within pathosystems, and also show that models are modular components within the framework and can be extended. This is illustrated by testing the impact of canopy architectural traits on fungal dispersal. This study provides a framework for modelling a large number of pathosystems using FSPMs. This structure can accommodate both
Tolkkinen, M; Mykrä, H; Annala, M; Markkola, A M; Vuori, K M; Muotka, T
Biological assemblages are often subjected to multiple stressors emerging from both anthropogenic activities and naturally stressful conditions, and species' responses to simultaneous stressors may differ from those predicted based on the individual effects of each stressor alone. We studied the influence of land-use disturbance (forest drainage) on fungal decomposer assemblages and leaf decomposition rates in naturally harsh (low pH caused by black-shale dominated geology) vs. circumneutral streams. We used pyrosequencing to determine fungal richness and assemblage structure. Decomposition rates did not differ between circumneutral and naturally acidic reference sites. However, the effect of forest drainage on microbial decomposition was more pronounced in the naturally acidic streams than in circumneutral streams. Single-effect responses of fungal assemblages were mainly related to geology. Community similarity was significantly higher in the naturally acidic disturbed sites than in corresponding reference sites, suggesting that land-use disturbance simplifies fungal assemblages in naturally stressful conditions. Naturally acidic streams supported distinct fungal assemblages with many OTUs (operational taxonomic unit) unique to these streams. Our results indicate that fungal assemblages in streams are sensitive to both structural and functional impairment in response to multiple stressors. Anthropogenic degradation of naturally acidic streams may decrease regional fungal diversity and impair ecosystem functions, and these globally occurring environments therefore deserve special attention in conservation planning.
Mapari, Sameer Shamsuddin; Meyer, Anne S.; Thrane, Ulf
an enhanced photostability of fungal pigment extracts compared to the commercially available natural colorants Monascus Red and turmeric used as controls. Yellow components of the orange-red fungal pigment extract were more photostable than the red components. Chemistry of the photodegradation of the orange...
Nielsen, Maria Lund
Natural products have had a huge impact on the history of drug development, and today, these compounds continue to be a key source of novel drug leads. Over the years, natural products have been exploited for their pharmacological and biological activities in the treatment of many diseases....... Secondary metabolites (SMs) from bacteria, plants and filamentous fungi constitute a large group of important natural products. In this thesis I explore the biosynthesis of several fungal SMs along with the enzymes responsible for their synthesis. Specifically, my research focuses on the expression...... and engineering of a certain type of fungal enzymes – natural fusions of polyketide synthases and nonribosomal peptide synthetases (PKS-NRPSs). The thesis is divided into two topics: 1) Expanding fungal chemodiversity through combinatorial biosynthesis 2) Two CRISPR-Cas9-based approaches to linking SMs...
Full Text Available The aim of this work was to assess the possibility of using native bacterial nanocellulose (BC as a carrier for laccase immobilization. BC was synthesized by Gluconacetobacter xylinus, which was statically cultivated in a mannitol-based medium and was freeze-dried to form BC sponge after purification. For the first time, fungal laccase from Trametes versicolor was immobilized on the native nanofibril network-structured BC sponge through physical adsorption and cross-linking with glutaraldehyde. The properties including morphologic and structural features of the BC as well as the immobilized enzyme were thoroughly investigated. It was found that enzyme immobilized by cross-linking exhibited broader pH operation range of high catalytic activity as well as higher running stability compared to free and adsorbed enzyme. Using ABTS as substrate, the optimum pH value was 3.5 for the adsorption-immobilized laccase and 4.0 for the crosslinking-immobilized laccase. The immobilized enzyme retained 69% of the original activity after being recycled 7 times. Novel applications of the BC-immobilized enzyme tentatively include active packaging, construction of biosensors, and establishment of bioreactors.
Dembitsky, Valery M
This article focuses on the occurrence and biological activities of cyclobutane-containing (CBC) alkaloids obtained from fungi, fungal endophytes, and plants. Naturally occurring CBC alkaloids are of particular interest because many of these compounds display important biological activities and possess antitumour, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. Therefore, these compounds are of great interest in the fields of medicine, pharmacology, medicinal chemistry, and the pharmaceutical industry. Fermentation and production of CBC alkaloids by fungi and/or fungal endophytes is also discussed. This review presents the structures and describes the activities of 98 CBC alkaloids. Copyright © 2014. Published by Elsevier GmbH.
Sigoillot, C.; Record, E.; Belle, V.; Robert, J.L.; Levasseur, A.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Fournel, A.; Sigoillot, J.C.; Asther, M.
Three laccases, a natural form and two recombinant forms obtained from two different expression hosts, were characterized and compared for paper pulp bleaching. Laccase from Pycnoporus cinnabarinus, a well known lignolytic fungus, was selected as a reference for this study. The corresponding
Mueller, Rebecca C; Gallegos-Graves, Laverne; Zak, Donald R; Kuske, Cheryl R
Dormancy is thought to promote biodiversity within microbial communities, but how assembly of the active community responds to changes in environmental conditions is unclear. To measure the active and dormant communities of bacteria and fungi colonizing decomposing litter in maple forests, we targeted ribosomal genes and transcripts across a natural environmental gradient. Within bacterial and fungal communities, the active and dormant communities were phylogenetically distinct, but patterns of phylogenetic clustering varied. For bacteria, active communities were significantly more clustered than dormant communities, while the reverse was found for fungi. The proportion of operational taxonomic units (OTUs) classified as active and the degree of phylogenetic clustering of the active bacterial communities declined with increasing pH and decreasing C/N. No significant correlations were found for the fungal community. The opposing pattern of phylogenetic clustering in dormant and active communities and the differential response of active communities to environmental gradients suggest that dormancy differentially structures bacterial and fungal communities.
Mapari, Sameer Shamsuddin; Nielsen, Kristian Fog; Larsen, Thomas Ostenfeld
The production of many currently authorized natural food colorants has a number of disadvantages, including a dependence on the supply of raw materials and variations in pigment extraction. Fungi provide a readily available alternative source of naturally derived food colorants that could easily...... be produced in high yields. The recent authorization of a fungal food colorant has fuelled research to explore the extraordinary chemical diversity and biodiversity of fungi for the biotechnological production of pigments as natural food colorants. These studies require an appropriate use of chernotaxonomic...... tools and a priori knowledge of fungal metabolites to carry out intelligent screening for known or novel colorants as lead compounds. Such screening would result in the preselection of some potential pigment producers and the deselection of pathogenic strains and toxin producers. With advances in gene...
Nisa, Humeera; Kamili, Azra N; Nawchoo, Irshad A; Shafi, Sana; Shameem, Nowsheen; Bandh, Suhaib A
Endophytic fungi are those that live internally in apparently healthy and asymptomatic hosts. Endophytic fungi appear to be ubiquitous; indeed, no study has yet shown the existence of a plant species without endophytes. High species diversity is another characteristic of endophytic mycobiota which is depicted by the fact that it is quite common for endophyte surveys to find assemblages consisting of more than 30 fungal species per host plant species. Medicinal plants had been used to isolate and characterize directly the bioactive metabolites. However, the discovery of fungal endophytes inside these plants with capacity to produce the same compounds shifted the focus of new drug sources from plants to fungi. Bioactive natural products from endophytic fungi, isolated from different plant species, are attracting considerable attention from natural product chemists and biologists alike which is clearly depicted by the steady increase of publications devoted to this topic during the recent years. This review will highlight the chemical potential of endophytic fungi with focus on the detection of pharmaceutically valuable plant constituents as products of fungal biosynthesis. In addition, it will cover newly discovered endophytic fungi and also new bioactive metabolites reported in recent years from fungal endophytes. It summarizes the up-to-date and comprehensive information on bioactive compounds from endophytic fungi by having done a thorough survey of literature. Copyright © 2015 Elsevier Ltd. All rights reserved.
Full Text Available In this study, molecular markers were used to determine fungal flora in black olive fruits from field surveys to the table, following the fermentation process. Field samples were collected from different locations of Canakkale province, including Gokceada (Imbros, where organic farming is employed. Some of the fruits from field samples were used for black table olive production and then fungal flora was tracked during the fermentation process. Fungal isolation was also conducted on some commercial samples. Fifty seven isolates from field samples, 56 isolates from the fermentation process and 17 isolates from commercial products were obtained. Among these isolates, 41 Alternaria, 43 Penicillium, 19 Aspergillus, 8 Monascus and 19 other genera were determined using amplified sizes of the Beta-tubulin gene region. Species level identification was carried out based on sequences of Beta-tubulin amplicons, which provided accurate identification, especially where the genera were morphologically highly similar. The occurrence and prevalence of fungal species changed in fungal collections from the field to the fermentation process. While Alternaria alternata was common in field samples, they were absent during fermentation. Many of these identified species, such as Penicillium expansum, Aspergillus niger and Monascus pilosus, which are known as potential toxin producers such as aflatoxin, ochratoxin A and citrinin, were found both in natural and fermented samples, even at the end of the fermentation process. These results showed that some fungal species which survive on olives from the field to the table are potential toxin producers and can be successfully characterized by amplification and sequencing of Beta-tubulin gene.
Full Text Available BACKGROUND: Ophiocordyceps sinensis (syn. Cordyceps sinensis, which is a parasite of caterpillars and is endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. "Natural O. sinensis specimens" harbor various other fungi. Several of these other fungi that have been isolated from natural O. sinensis specimens have similar chemical components and/or pharmaceutical effects as O. sinensis. Nevertheless, the mycobiota of natural O. sinensis specimens has not been investigated in detail. METHODOLOGY/PRINCIPAL FINDINGS: Based on the technique of PCR-single-strand conformation polymorphism (PCR-SSCP, the mycobiota of three different sections (stromata, sclerotia, and mycelial cortices from natural O. sinensis specimens were investigated using both culture-dependent and -independent methods. For the culture-dependent method, 572 fungal strains were isolated, and 92 putative operational taxonomic units (OTUs were identified from 226 sequenced strains with the threshold of 97%. For the culture-independent method, 490 fungal clones were identified from about 3000 clones of ITS fragments from the whole-community DNA; based on PCR-SSCP analyses, 266 of these clones were selected to be sequenced, and 118 putative OTUs were detected. The overwhelming majority of isolates/clones and OTUs were detected from mycelial cortices; only a few were detected from stromata and sclerotia. The most common OTUs detected with both methods belonged to Ascomycota; however, only 13 OTUs were detected simultaneously by both methods. Potential novel lineages were detected by each of the two methods. CONCLUSIONS/SIGNIFICANCE: A great number of fungal species present in the mycobiota of naturally-occurring O. sinensis specimens were detected, and many of them may represent undescribed lineages. That only a few of the same OTUs were detected by both methods indicated that different methods should be used. This study increased our
Kamu, Assis; Phin, Chong Khim; Seman, Idris Abu; Wan, Hoong Hak; Mun, Ho Chong
Oil palm or scientifically known as Elaeis guineensis Jacq. is the most important commodity crop in Malaysia and has greatly contributed to the economy growth of the country. As far as disease is concerned in the industry, Basal Stem Rot (BSR) caused by Ganoderma boninence remains the most important disease. BSR disease is the most widely studied with information available for oil palm disease in Malaysia. However, there is still limited study on the spatial as well as temporal pattern or distribution of the disease especially under natural field epidemic condition in oil palm plantation. The objective of this study is to spatially identify the pattern of BSR disease under natural field epidemic using two geospatial analytical techniques, which are quadrat analysis for the first order properties of partial pattern analysis and nearest-neighbor analysis (NNA) for the second order properties of partial pattern analysis. Two study sites were selected with different age of tree. Both sites are located in Tawau, Sabah and managed by the same company. The results showed that at least one of the point pattern analysis used which is NNA (i.e. the second order properties of partial pattern analysis) has confirmed the disease is complete spatial randomness. This suggests the spread of the disease is not from tree to tree and the age of palm does not play a significance role in determining the spatial pattern of the disease. From the spatial pattern of the disease, it would help in the disease management program and for the industry in the future. The statistical modelling is expected to help in identifying the right model to estimate the yield loss of oil palm due to BSR disease in the future.
Crawford, Bryn; Pakpour, Sepideh; Kazemian, Negin; Klironomos, John; Stoeffler, Karen; Rho, Denis; Denault, Johanne; Milani, Abbas S
The development and application of bio-sourced composites have been gaining wide attention, yet their deterioration due to the growth of ubiquitous microorganisms during storage/manufacturing/in-service phases is still not fully understood for optimum material selection and design purposes. In this study, samples of non-woven flax fibers, hemp fibers, and mats made of co-mingled randomly-oriented flax or hemp fiber (50%) and polypropylene fiber (50%) were subjected to 28 days of exposure to (i) no water-no fungi, (ii) water only and (iii) water along with the Chaetomium globosum fungus. Biocomposite samples were measured for weight loss over time, to observe the rate of fungal growth and the respiration of cellulose components in the fibers. Tensile testing was conducted to measure mechanical properties of the composite samples under different configurations. Scanning electron microscopy was employed to visualize fungal hyphal growth on the natural fibers, as well as to observe the fracture planes and failure modes of the biocomposite samples. Results showed that fungal growth significantly affects the dry mass as well as the tensile elastic modulus of the tested natural fiber mats and composites, and the effect depends on both the type and the length scale of fibers, as well as the exposure condition and time.
Full Text Available The development and application of bio-sourced composites have been gaining wide attention, yet their deterioration due to the growth of ubiquitous microorganisms during storage/manufacturing/in-service phases is still not fully understood for optimum material selection and design purposes. In this study, samples of non-woven flax fibers, hemp fibers, and mats made of co-mingled randomly-oriented flax or hemp fiber (50% and polypropylene fiber (50% were subjected to 28 days of exposure to (i no water-no fungi, (ii water only and (iii water along with the Chaetomium globosum fungus. Biocomposite samples were measured for weight loss over time, to observe the rate of fungal growth and the respiration of cellulose components in the fibers. Tensile testing was conducted to measure mechanical properties of the composite samples under different configurations. Scanning electron microscopy was employed to visualize fungal hyphal growth on the natural fibers, as well as to observe the fracture planes and failure modes of the biocomposite samples. Results showed that fungal growth significantly affects the dry mass as well as the tensile elastic modulus of the tested natural fiber mats and composites, and the effect depends on both the type and the length scale of fibers, as well as the exposure condition and time.
d'Errico, Clotilde; Börjesson, Johan; Ding, Hanshu
between glucuronic acids in xylans and lignin alcohols. By means of synthesized complex LCC model substrates we provide kinetic data suggesting a preference of fungal GEs for esters of bulky arylalkyl alcohols such as ester LCCs. Furthermore, using natural corn fiber substrate we report the first examples...... of improved degradation of lignocellulosic biomass by the use of GEs. Improved C5 sugar, glucose and glucuronic acid release was observed when heat pretreated corn fiber was incubated in the presence of GEs from Cerrena unicolor and Trichoderma reesei on top of different commercial cellulase...
Maček, Irena; Dumbrell, Alex J; Nelson, Michaela; Fitter, Alastair H; Vodnik, Dominik; Helgason, Thorunn
The processes responsible for producing and maintaining the diversity of natural arbuscular mycorrhizal (AM) fungal communities remain largely unknown. We used natural CO(2) springs (mofettes), which create hypoxic soil environments, to determine whether a long-term, directional, abiotic selection pressure could change AM fungal community structure and drive the selection of particular AM fungal phylotypes. We explored whether those phylotypes that appear exclusively in hypoxic soils are local specialists or widespread generalists able to tolerate a range of soil conditions. AM fungal community composition was characterized by cloning, restriction fragment length polymorphism typing, and the sequencing of small subunit rRNA genes from roots of four plant species growing at high (hypoxic) and low (control) geological CO(2) exposure. We found significant levels of AM fungal community turnover (β diversity) between soil types and the numerical dominance of two AM fungal phylotypes in hypoxic soils. Our results strongly suggest that direct environmental selection acting on AM fungi is a major factor regulating AM fungal communities and their phylogeographic patterns. Consequently, some AM fungi are more strongly associated with local variations in the soil environment than with their host plant's distribution.
The outbreak of porcine epidemic diarrhea virus (PEDv) in North America has substantially impacted U.S. swine production in recent years. The virus it is easily transmitted among pigs and causes nearly 100% mortality in pre-weaned piglets. Because PEDv is an enteric virus spread via fecal-oral conta...
Yang, Teng; Adams, Jonathan M; Shi, Yu; He, Jin-Sheng; Jing, Xin; Chen, Litong; Tedersoo, Leho; Chu, Haiyan
Previous studies have revealed inconsistent correlations between fungal diversity and plant diversity from local to global scales, and there is a lack of information about the diversity-diversity and productivity-diversity relationships for fungi in alpine regions. Here we investigated the internal relationships between soil fungal diversity, plant diversity and productivity across 60 grassland sites on the Tibetan Plateau, using Illumina sequencing of the internal transcribed spacer 2 (ITS2) region for fungal identification. Fungal alpha and beta diversities were best explained by plant alpha and beta diversities, respectively, when accounting for environmental drivers and geographic distance. The best ordinary least squares (OLS) multiple regression models, partial least squares regression (PLSR) and variation partitioning analysis (VPA) indicated that plant richness was positively correlated with fungal richness. However, no correlation between plant richness and fungal richness was evident for fungal functional guilds when analyzed individually. Plant productivity showed a weaker relationship to fungal diversity which was intercorrelated with other factors such as plant diversity, and was thus excluded as a main driver. Our study points to a predominant effect of plant diversity, along with other factors such as carbon : nitrogen (C : N) ratio, soil phosphorus and dissolved organic carbon, on soil fungal richness. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
Hui, Nan; Liu, Xinxin; Kotze, D Johan; Jumpponen, Ari; Francini, Gaia; Setälä, Heikki
Ectomycorrhizal (ECM) fungi are important mutualists for the growth and health of most boreal trees. Forest age and its host species composition can impact the composition of ECM fungal communities. Although plentiful empirical data exist for forested environments, the effects of established vegetation and its successional trajectories on ECM fungi in urban greenspaces remain poorly understood. We analyzed ECM fungi in 5 control forests and 41 urban parks of two plant functional groups (conifer and broadleaf trees) and in three age categories (10, ∼50, and >100 years old) in southern Finland. Our results show that although ECM fungal richness was marginally greater in forests than in urban parks, urban parks still hosted rich and diverse ECM fungal communities. ECM fungal community composition differed between the two habitats but was driven by taxon rank order reordering, as key ECM fungal taxa remained largely the same. In parks, the ECM communities differed between conifer and broadleaf trees. The successional trajectories of ECM fungi, as inferred in relation to the time since park construction, differed among the conifers and broadleaf trees: the ECM fungal communities changed over time under the conifers, whereas communities under broadleaf trees provided no evidence for such age-related effects. Our data show that plant-ECM fungus interactions in urban parks, in spite of being constructed environments, are surprisingly similar in richness to those in natural forests. This suggests that the presence of host trees, rather than soil characteristics or even disturbance regime of the system, determine ECM fungal community structure and diversity. IMPORTANCE In urban environments, soil and trees improve environmental quality and provide essential ecosystem services. ECM fungi enhance plant growth and performance, increasing plant nutrient acquisition and protecting plants against toxic compounds. Recent evidence indicates that soil-inhabiting fungal communities
Paguigan, Noemi D; Al-Huniti, Mohammed H; Raja, Huzefa A; Czarnecki, Austin; Burdette, Joanna E; González-Medina, Mariana; Medina-Franco, José L; Polyak, Stephen J; Pearce, Cedric J; Croatt, Mitchell P; Oberlies, Nicholas H
Griseofulvin is a fungal metabolite and antifungal drug used for the treatment of dermatophytosis in both humans and animals. Recently, griseofulvin and its analogues have attracted renewed attention due to reports of their potential anticancer effects. In this study griseofulvin (1) and related analogues (2-6, with 4 being new to literature) were isolated from Xylaria cubensis. Six fluorinated analogues (7-12) were synthesized, each in a single step using the isolated natural products and Selectflour, so as to examine the effects of fluorine incorporation on the bioactivities of this structural class. The isolated and synthesized compounds were screened for activity against a panel of cancer cell lines (MDA-MB-435, MDA-MB-231, OVCAR3, and Huh7.5.1) and for antifungal activity against Microsporum gypseum. A comparison of the chemical space occupied by the natural and fluorinated analogues was carried out by using principal component analysis, documenting that the isolated and fluorinated analogues occupy complementary regions of chemical space. However, the most active compounds, including two fluorinated derivatives, were centered around the chemical space that was occupied by the parent compound, griseofulvin, suggesting that modifications must preserve certain attributes of griseofulvin to conserve its activity. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Santiago, Iara F; Soares, Marco Aurélio; Rosa, Carlos A; Rosa, Luiz H
We surveyed the diversity, distribution and ecology of non-lichenised fungal communities associated with the Antarctic lichens Usnea antarctica and Usnea aurantiaco-atra across Antarctica. The phylogenetic study of the 438 fungi isolates identified 74 taxa from 21 genera of Ascomycota, Basidiomycota and Zygomycota. The most abundant taxa were Pseudogymnoascus sp., Thelebolus sp., Antarctomyces psychrotrophicus and Cryptococcus victoriae, which are considered endemic and/or highly adapted to Antarctica. Thirty-five fungi may represent new and/or endemic species. The fungal communities displayed high diversity, richness and dominance indices; however, the similarity among the communities was variable. After discovering rich and diverse fungal communities composed of symbionts, decomposers, parasites and endemic and cold-adapted cosmopolitan taxa, we introduced the term "lichensphere". We hypothesised that the lichensphere may represent a protected natural microhabitat with favourable conditions able to help non-lichenised fungi and other Antarctic life forms survive and disperse in the extreme environments of Antarctica.
Aranda, M A; Fraile, A; Garcia-Arenal, F
The genetic structure of populations of cucumber mosaic virus (CMV) satellite RNA (satRNA) and its evolution were analyzed during the course of a CMV epidemic in tomatoes in eastern Spain. A total of 62 variants of CMV-satRNA from epidemic episodes in 1989, 1990, and 1991 were characterized by RNase protection assay (RPA); RPA patterns defined 60 haplotypes in the CMV-satRNA population. RPA of nine CMV-satRNAs of known sequences showed that numbers of nucleotide substitutions per site (dij) between different satRNAs can be estimated from RPA data. Thus, dij were estimated for any possible pair of field CMV-satRNA types, and nucleotide diversities within and between yearly subpopulations were calculated. Also, phylogenetic relationships among CMV-satRNAs were derived from RPA data (by parsimony) or from dij (by neighbor joining). From these analyses, a model for the evolution of CMV-satRNAs in field epidemics can be built. High genetic variability of CMV-satRNA results in very heterogeneous populations, even compared with those of other RNA genomes. The high diversity of the population is maintained through time by the continuous generation of variants by mutation, counterbalanced by negative selection; this results in a certain replacement of haplotypes from year to year. The sequential accumulation of mutations in CMV-satRNA leads to fast genetic divergence to reach what appears to be an upper permitted threshold. Images PMID:7690414
d'Errico, Clotilde; Börjesson, Johan; Ding, Hanshu; Krogh, Kristian B R M; Spodsberg, Nikolaj; Madsen, Robert; Monrad, Rune Nygaard
Lignin-carbohydrate complexes (LCCs) are in part responsible for the recalcitrance of lignocellulosics in relation to industrial utilization of biomass for biofuels. Glucuronoyl esterases (GEs) belonging to the carbohydrate esterase family 15 have been proposed to be able to degrade ester LCCs between glucuronic acids in xylans and lignin alcohols. By means of synthesized complex LCC model substrates we provide kinetic data suggesting a preference of fungal GEs for esters of bulky arylalkyl alcohols such as ester LCCs. Furthermore, using natural corn fiber substrate we report the first examples of improved degradation of lignocellulosic biomass by the use of GEs. Improved C5 sugar, glucose and glucuronic acid release was observed when heat pretreated corn fiber was incubated in the presence of GEs from Cerrena unicolor and Trichoderma reesei on top of different commercial cellulase/hemicellulase preparations. These results emphasize the potential of GEs for delignification of biomass thereby improving the overall yield of fermentable sugars for biofuel production. Copyright © 2015 Elsevier B.V. All rights reserved.
Overy, David P; Berrue, Fabrice; Correa, Hebelin; Hanif, Novriyandi; Hay, Kathryn; Lanteigne, Martin; Mquilian, Kathrine; Duffy, Stephanie; Boland, Patricia; Jagannathan, Ramesh; Carr, Gavin S; Vansteeland, Marieke; Kerr, Russell G
Due to a rate increase in the resistance of microbial pathogens to currently used antibiotics, there is a need in society for the discovery of novel antimicrobials. Historically, fungi are a proven source for antimicrobial compounds. The main goals of this study were to investigate the fungal diversity associated with sea foam collected around the coast of Prince Edward Island and the utility of this resource for the production of antimicrobial natural products. Obtained isolates were identified using ITS and nLSU rDNA sequences, fermented on four media, extracted and fractions enriched in secondary metabolites were screened for antimicrobial activity. The majority of the isolates obtained were ascomycetes, consisting of four recognized marine taxa along with other ubiquitous genera and many 'unknown' isolates that could not be identified to the species level using rDNA gene sequences. Secondary metabolite isolation efforts lead to the purification of the metabolites epolones A and B, pycnidione and coniothyrione from a strain of Neosetophoma samarorum ; brefeldin A, leptosin J and the metabolite TMC-264 from an unknown fungus (probably representative of an Edenia sp.); and 1-hydroxy-6-methyl-8-hydroxymethylxanthone, chrysophanol and chrysophanol bianthrone from a Phaeospheria spartinae isolate. The biological activity of each of these metabolites was assessed against a panel of microbial pathogens as well as several cell lines.
Burco, Julia D; Massey, J Gregory; Byrne, Barbara A; Tell, Lisa; Clemons, Karl V; Ziccardi, Michael H
Aspergillosis remains a major cause of mortality in captive and rehabilitated seabirds. To date, there has been poor documentation of fungal (particularly Aspergillus spp.) burdens in natural seabird loafing and roosting sites compared with fungal numbers in rehabilitation or captive settings and the various microenvironments that seabirds are exposed to during the rehabilitation process. This study compares fungal, particularly Aspergillus spp., burdens potentially encountered by seabirds in natural and rehabilitation environments. Differences among the various microenvironments in the rehabilitation facility were evaluated to determine the risk of infection when seabirds are experiencing high stress and poor immune function. Aspergillus spp. counts were quantified in three wildlife rehabilitation centers and five natural seabird loafing and roosting sites in northern California using a handheld impact air sampler and a water filtration system. Wildlife rehabilitation centers demonstrated an increase in numbers of conidia of Aspergillus spp. and Aspergillus fumigatus in air and water samples from select aquatic bird rehabilitation centers compared with natural seabird environments in northern California. Various microenvironments in the rehabilitation facility were identified as having higher numbers of conidia of Aspergillus spp. These results suggest that periodic monitoring of multiple local areas, where the birds spend time in a rehabilitation facility, should be done to identify "high risk" sites, where birds should spend minimal time, or sites that should be cleaned more frequently or have improved air flow to reduce exposure to fungal conidia. Overall, these results suggest that seabirds may be more likely to encounter Aspergillus spp. in various microenvironments in captivity, compared with their native habitats, which could increase their risk of developing disease when in a debilitated state.
Zacchino, Susana A; Butassi, Estefanía; Cordisco, Estefanía; Svetaz, Laura A
works respectively. Regarding combinations against bacterial biofilms, in vitro studies were performed in all works by using several different methods of higher variety than the used against fungal biofilms. Biofilms of both the gram (+) and gram (-) bacteria were prepared, although biofilm of Staphylococcus spp. were the most used in the collected works. Among the discovered potentiators of antibacterial drugs, 75% were terpenes, including mono, di- and triterpenes, and, among the atibacterial drugs, several structurally diverse types were used in the combinations: aminoglycosides, β-lactams, glucopeptides and fluoroquinolones. The potentiating capacity of natural products, mainly terpenes, on the antibiofilm effect of antimicrobial drugs opens a wide range of possibilities for the combination antimicrobial therapy. More in vivo studies on combinations of natural products with antimicrobial drugs acting against biofilms are highly required to cope the difficult to treat biofilm-associated infections. Copyright © 2017 Elsevier GmbH. All rights reserved.
Elliott, David R.; Caporn, Simon J. M.; Nwaishi, Felix; Nilsson, R. Henrik; Sen, Robin
The UK hosts 15–19% of global upland ombrotrophic (rain fed) peatlands that are estimated to store 3.2 billion tonnes of carbon and represent a critical upland habitat with regard to biodiversity and ecosystem services provision. Net production is dependent on an imbalance between growth of peat-forming Sphagnum mosses and microbial decomposition by microorganisms that are limited by cold, acidic, and anaerobic conditions. In the Southern Pennines, land-use change, drainage, and over 200 years of anthropogenic N and heavy metal deposition have contributed to severe peatland degradation manifested as a loss of vegetation leaving bare peat susceptible to erosion and deep gullying. A restoration programme designed to regain peat hydrology, stability and functionality has involved re-vegetation through nurse grass, dwarf shrub and Sphagnum re-introduction. Our aim was to characterise bacterial and fungal communities, via high-throughput rRNA gene sequencing, in the surface acrotelm/mesotelm of degraded bare peat, long-term stable vegetated peat, and natural and managed restorations. Compared to long-term vegetated areas the bare peat microbiome had significantly higher levels of oligotrophic marker phyla (Acidobacteria, Verrucomicrobia, TM6) and lower Bacteroidetes and Actinobacteria, together with much higher ligninolytic Basidiomycota. Fewer distinct microbial sequences and significantly fewer cultivable microbes were detected in bare peat compared to other areas. Microbial community structure was linked to restoration activity and correlated with soil edaphic variables (e.g. moisture and heavy metals). Although rapid community changes were evident following restoration activity, restored bare peat did not approach a similar microbial community structure to non-eroded areas even after 25 years, which may be related to the stabilisation of historic deposited heavy metals pollution in long-term stable areas. These primary findings are discussed in relation to bare
David R Elliott
Full Text Available The UK hosts 15-19% of global upland ombrotrophic (rain fed peatlands that are estimated to store 3.2 billion tonnes of carbon and represent a critical upland habitat with regard to biodiversity and ecosystem services provision. Net production is dependent on an imbalance between growth of peat-forming Sphagnum mosses and microbial decomposition by microorganisms that are limited by cold, acidic, and anaerobic conditions. In the Southern Pennines, land-use change, drainage, and over 200 years of anthropogenic N and heavy metal deposition have contributed to severe peatland degradation manifested as a loss of vegetation leaving bare peat susceptible to erosion and deep gullying. A restoration programme designed to regain peat hydrology, stability and functionality has involved re-vegetation through nurse grass, dwarf shrub and Sphagnum re-introduction. Our aim was to characterise bacterial and fungal communities, via high-throughput rRNA gene sequencing, in the surface acrotelm/mesotelm of degraded bare peat, long-term stable vegetated peat, and natural and managed restorations. Compared to long-term vegetated areas the bare peat microbiome had significantly higher levels of oligotrophic marker phyla (Acidobacteria, Verrucomicrobia, TM6 and lower Bacteroidetes and Actinobacteria, together with much higher ligninolytic Basidiomycota. Fewer distinct microbial sequences and significantly fewer cultivable microbes were detected in bare peat compared to other areas. Microbial community structure was linked to restoration activity and correlated with soil edaphic variables (e.g. moisture and heavy metals. Although rapid community changes were evident following restoration activity, restored bare peat did not approach a similar microbial community structure to non-eroded areas even after 25 years, which may be related to the stabilisation of historic deposited heavy metals pollution in long-term stable areas. These primary findings are discussed in
Hay, D B; Hart, B J; Pearce, R B; Kozakiewicz, Z; Douglas, A E
Both house dust and house dust mites Dermatophagoides pteronyssinus contained a wider range of fungi than laboratory mite cultures. In total, nine species of fungi were isolated from D. pteronyssinus in house dust, and these included three xerophilic species (Eurotium amstelodami, Aspergillus penicillioides and Wallemia sebi) commonly found in laboratory cultures of D. pteronyssinus. It is concluded that mites do interact with a similar range of fungi in natural dust and in laboratory culture, but that the diversity of fungal species in the laboratory is reduced and the density of individual fungal species in culture exceeds that of house dust. In a second experiment, dust samples were incubated at room temperature with 75% relative humidity. The diversity of fungi invariably declined from up to 13 genera to the few species recorded in laboratory culture. This suggests that the dominance of xerophilic fungi in laboratory mite rearings is mediated primarily by low relative humidity, and the exclusion of air-borne spores.
Ódor, P.; Heilmann-Clausen, J.; Christensen, M.; Aude, E.; Dort, van K.W.; Piltaver, A.; Siller, I.; Veerkamp, M.T.; Walleyn, R.; Standovár, T.; Hees, van A.F.M.; Kosec, J.; Matocec, N.; Kraigher, H.; Grebenc, T.
Saproxylic organisms are among the most threatened species in Europe and constitute a major conservation problem because they depend on the most important forestry product - dead wood. Diversity of fungal and bryophyte communities occurring on dead beech trees was analyzed in five European countries
Svobodová, Kateřina; Mikesková, Hana; Petráčková, Denisa
Roč. 97, č. 24 (2013), s. 10263-10273 ISSN 0175-7598 R&D Projects: GA TA ČR TE01020218 Institutional support: RVO:61388971 Keywords : Fungal microsomes * Cytochrome P450 * Biodegradation Subject RIV: EE - Microbiology, Virology Impact factor: 3.811, year: 2013
Chen, Nanhua; Li, Shuangjie; Zhou, Rongyun; Zhu, Meiqin; He, Shan; Ye, Mengxue; Huang, Yucheng; Li, Shuai; Zhu, Cong; Xia, Pengpeng; Zhu, Jianzhong
Porcine epidemic diarrhea virus (PEDV) causes devastating impact on global pig-breeding industry and current vaccines have become not effective against the circulating PEDV variants since 2011. During the up-to-date investigation of PEDV prevalence in Fujian China 2016, PEDV was identified in vaccinated pig farms suffering severe diarrhea while other common diarrhea-associated pathogens were not detected. Complete genomes of two PEDV representatives (XM1-2 and XM2-4) were determined. Genomic comparison showed that these two viruses share the highest nucleotide identities (99.10% and 98.79%) with the 2011 ZMDZY strain, but only 96.65% and 96.50% nucleotide identities with the attenuated CV777 strain. Amino acid alignment of spike (S) proteins indicated that they have the similar mutation, insertion and deletion pattern as other Chinese PEDV variants but also contain several unique substitutions. Phylogenetic analysis showed that 2016 PEDV variants belong to the cluster of recombination strains but form a new branch. Recombination detection suggested that both XM1-2 and XM2-4 are inter-subgroup recombinants with breakpoints within ORF1b. Remarkably, the natural recombinant HNQX-3 isolate serves as a parental virus for both natural recombinants identified in this study. This up-to-date investigation provides the direct evidence that natural recombinants may serve as parental viruses to generate recombined PEDV progenies that are probably associated with the vaccination failure. Copyright © 2017. Published by Elsevier B.V.
Peter K Busk
Full Text Available The cellulose-degrading fungal enzymes are glycoside hydrolases of the GH families and lytic polysaccharide monooxygenases. The entanglement of glycoside hydrolase families and functions makes it difficult to predict the enzymatic activity of glycoside hydrolases based on their sequence. In the present study we further developed the method Peptide Pattern Recognition to an automatic approach not only to find all genes encoding glycoside hydrolases and lytic polysaccharide monooxygenases in fungal genomes but also to predict the function of the genes. The functional annotation is an important feature as it provides a direct route to predict function from primary sequence. Furthermore, we used Peptide Pattern Recognition to compare the cellulose-degrading enzyme activities encoded by 39 fungal genomes. The results indicated that cellobiohydrolases and AA9 lytic polysaccharide monooxygenases are hallmarks of cellulose-degrading fungi except brown rot fungi. Furthermore, a high number of AA9, endocellulase and β-glucosidase genes were identified, not in what are known to be the strongest, specialized lignocellulose degraders but in saprophytic fungi that can use a wide variety of substrates whereas only few of these genes were found in fungi that have a limited number of natural, lignocellulotic substrates. This correlation suggests that enzymes with different properties are necessary for degradation of cellulose in different complex substrates. Interestingly, clustering of the fungi based on their predicted enzymes indicated that Ascomycota and Basidiomycota use the same enzymatic activities to degrade plant cell walls.
Mapari, Sameer As; Meyer, Anne S; Thrane, Ulf; Frisvad, Jens C
Colorants derived from natural sources look set to overtake synthetic colorants in market value as manufacturers continue to meet the rising demand for clean label ingredients - particularly in food applications. Many ascomycetous fungi naturally synthesize and secrete pigments and thus provide readily available additional and/or alternative sources of natural colorants that are independent of agro-climatic conditions. With an appropriately selected fungus; using in particular chemotaxonomy as a guide, the fungal natural colorants could be produced in high yields by using the optimized cultivation technology. This approach could secure efficient production of pigments avoiding use of genetic manipulation. Polyketide pigment producing ascomycetous fungi were evaluated for their potential as production organisms based on a priori knowledge on species-specific pigment and potential mycotoxin production and BioSafety level (BSL) classification. Based on taxonomic knowledge, we pre-selected ascomycetous fungi belonging to Penicillium subgenus Biverticillium that produced yellow, orange or red pigments while deselecting Penicillium marneffei; a well known human pathogen in addition to other mycotoxigenic fungi belonging to the same group. We identified 10 strains belonging to 4 species; viz. P. purpurogenum, P. aculeatum, P. funiculosum, and P. pinophilum as potential pigment producers that produced Monascus-like pigments but no known mycotoxins. The selection/deselection protocol was illustrated in the pigment extracts of P. aculeatum IBT 14259 and P. crateriforme IBT 5015 analysed by HPLC-DAD-MS. In addition, extracellular pigment producing ability of some of the potential pigment producers was evaluated in liquid media with a solid support and N-glutarylmonascorubramine was discovered in the partially purified pigment extract of P. purpurogenum IBT 11181 and IBT 3645. The present work brought out that the use of chemotaxonomic tools and a priori knowledge of fungal
Frisvad Jens C
Full Text Available Abstract Background Colorants derived from natural sources look set to overtake synthetic colorants in market value as manufacturers continue to meet the rising demand for clean label ingredients – particularly in food applications. Many ascomycetous fungi naturally synthesize and secrete pigments and thus provide readily available additional and/or alternative sources of natural colorants that are independent of agro-climatic conditions. With an appropriately selected fungus; using in particular chemotaxonomy as a guide, the fungal natural colorants could be produced in high yields by using the optimized cultivation technology. This approach could secure efficient production of pigments avoiding use of genetic manipulation. Results Polyketide pigment producing ascomycetous fungi were evaluated for their potential as production organisms based on a priori knowledge on species-specific pigment and potential mycotoxin production and BioSafety level (BSL classification. Based on taxonomic knowledge, we pre-selected ascomycetous fungi belonging to Penicillium subgenus Biverticillium that produced yellow, orange or red pigments while deselecting Penicillium marneffei; a well known human pathogen in addition to other mycotoxigenic fungi belonging to the same group. We identified 10 strains belonging to 4 species; viz. P. purpurogenum, P. aculeatum, P. funiculosum, and P. pinophilum as potential pigment producers that produced Monascus-like pigments but no known mycotoxins. The selection/deselection protocol was illustrated in the pigment extracts of P. aculeatum IBT 14259 and P. crateriforme IBT 5015 analysed by HPLC-DAD-MS. In addition, extracellular pigment producing ability of some of the potential pigment producers was evaluated in liquid media with a solid support and N-glutarylmonascorubramine was discovered in the partially purified pigment extract of P. purpurogenum IBT 11181 and IBT 3645. Conclusion The present work brought out that the use
Mapari, Sameer AS; Meyer, Anne S; Thrane, Ulf; Frisvad, Jens C
Background Colorants derived from natural sources look set to overtake synthetic colorants in market value as manufacturers continue to meet the rising demand for clean label ingredients – particularly in food applications. Many ascomycetous fungi naturally synthesize and secrete pigments and thus provide readily available additional and/or alternative sources of natural colorants that are independent of agro-climatic conditions. With an appropriately selected fungus; using in particular chemotaxonomy as a guide, the fungal natural colorants could be produced in high yields by using the optimized cultivation technology. This approach could secure efficient production of pigments avoiding use of genetic manipulation. Results Polyketide pigment producing ascomycetous fungi were evaluated for their potential as production organisms based on a priori knowledge on species-specific pigment and potential mycotoxin production and BioSafety level (BSL) classification. Based on taxonomic knowledge, we pre-selected ascomycetous fungi belonging to Penicillium subgenus Biverticillium that produced yellow, orange or red pigments while deselecting Penicillium marneffei; a well known human pathogen in addition to other mycotoxigenic fungi belonging to the same group. We identified 10 strains belonging to 4 species; viz. P. purpurogenum, P. aculeatum, P. funiculosum, and P. pinophilum as potential pigment producers that produced Monascus-like pigments but no known mycotoxins. The selection/deselection protocol was illustrated in the pigment extracts of P. aculeatum IBT 14259 and P. crateriforme IBT 5015 analysed by HPLC-DAD-MS. In addition, extracellular pigment producing ability of some of the potential pigment producers was evaluated in liquid media with a solid support and N-glutarylmonascorubramine was discovered in the partially purified pigment extract of P. purpurogenum IBT 11181 and IBT 3645. Conclusion The present work brought out that the use of chemotaxonomic tools and
Vujanovic, Silva; Goh, Yit Kheng; Vujanovic, Vladimir
Currently, most synthetic dyes utilized for fungal fluorescent staining are toxic, carcinogenic, or harmful to animals, humans, and the environment. This study proposes non-toxic extracts of fruits from the genera Rhamnus, Ribes, Sambucus, Viburnum, Sorbus and Beta as simple, safe, and ecological alternatives to chemical fluorescent dye for efficient staining of Fusarium chlamydospore cells using, as test strains, five different pathogenic Fusarium species.
Full Text Available This work studied the mechanical, physical and weathering properties and anti-fungal efficacy of polyvinyl chloride(PVC and wood flour/polyvinyl chloride composites(WPVC. 2-hydroxypropyl-3-piperazinyl-quinoline carboxylic acid methacrylate (HPQM in propylene glycol was used as an anti-fungal agent. Propylene glycol-based HPQM was doped in neat PVC and in WPVC containing 50 and 100 pph wood (WPVC-50 and WPVC-100. The flexural properties of PVC decreased when propylene glycol-based HPQM was added. However, adding this component did not affect the flexural properties of WPVC. Fungal growth inhibition test and dry weight technique were used for evaluation of anti-fungal effectiveness. Aspergillus niger was used as a testing fungus. Adding propylene glycol-based HPQM to WPVC-100 led to the most effective anti-fungal performance. Wood flour acted as an anti-fungal promoter for the WPVC composites. The optimal dosages of propylene glycol-based HPQM in PVC, WPVC-50, and WPVC-100 were 50000, 15000, and 10000 ppm, respectively. UV-accelerated weathering aging and natural weathering conditions were found to affect the flexural properties of PVC and WPVC. The change in the anti-microbial performance of WPVC under natural weathering were slower than those under UV-accelerated weathering aging. The anti-microbial evaluation indicated that the samples doped with less than 20000 ppm propylene glycol-based HPQM had a more pronounced effect than the ones doped with higher dosages.
... Español Eye Health / Eye Health A-Z Fungal Keratitis Sections What is Fungal Keratitis? Fungal Keratitis Causes ... Keratitis Symptoms Fungal Keratitis Treatment What is Fungal Keratitis? Leer en Español: ¿Qué Es la Queratitis Fúngica? ...
Alele, Peter O; Sheil, Douglas; Surget-Groba, Yann; Lingling, Shi; Cannon, Charles H
Uganda's forests are globally important for their conservation values but are under pressure from increasing human population and consumption. In this study, we examine how conversion of natural forest affects soil bacterial and fungal communities. Comparisons in paired natural forest and human-converted sites among four locations indicated that natural forest soils consistently had higher pH, organic carbon, nitrogen, and calcium, although variation among sites was large. Despite these diffe...
Freedman, Jan E; Grodowitz, Michael J; Swindle, Robin; Nachtrieb, Julie G
...) scientists to identify naturalized and/or native herbivores of aquatic plants in an effort to develop alternative management strategies through an understanding of the agents' biology and ecology...
Schnoor, Tim Krone; Lekberg, Ylva; Rosendahl, Søren
While the effect of disturbance on overall abundance and community composition of arbuscular mycorrhizal (AM) fungi has been researched in agricultural fields, less is known about the impact in semi-natural grasslands. We sampled two AM plant species, Festuca brevipila and Plantago lanceolata, from...
Dennis J. Baumgardner
Full Text Available Fungal infections as a result of freshwater exposure or trauma are fortunately rare. Etiologic agents are varied, but commonly include filamentous fungi and Candida. This narrative review describes various sources of potential freshwater fungal exposure and the diseases that may result, including fungal keratitis, acute otitis externa and tinea pedis, as well as rare deep soft tissue or bone infections and pulmonary or central nervous system infections following traumatic freshwater exposure during natural disasters or near-drowning episodes. Fungal etiology should be suspected in appropriate scenarios when bacterial cultures or molecular tests are normal or when the infection worsens or fails to resolve with appropriate antibacterial therapy.
Peter O Alele
Full Text Available Uganda's forests are globally important for their conservation values but are under pressure from increasing human population and consumption. In this study, we examine how conversion of natural forest affects soil bacterial and fungal communities. Comparisons in paired natural forest and human-converted sites among four locations indicated that natural forest soils consistently had higher pH, organic carbon, nitrogen, and calcium, although variation among sites was large. Despite these differences, no effect on the diversity of dominant taxa for either bacterial or fungal communities was detected, using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE. Composition of fungal communities did generally appear different in converted sites, but surprisingly, we did not observe a consistent pattern among sites. The spatial distribution of some taxa and community composition was associated with soil pH, organic carbon, phosphorus and sodium, suggesting that changes in soil communities were nuanced and require more robust metagenomic methods to understand the various components of the community. Given the close geographic proximity of the paired sampling sites, the similarity between natural and converted sites might be due to continued dispersal between treatments. Fungal communities showed greater environmental differentiation than bacterial communities, particularly according to soil pH. We detected biotic homogenization in converted ecosystems and substantial contribution of β-diversity to total diversity, indicating considerable geographic structure in soil biota in these forest communities. Overall, our results suggest that soil microbial communities are relatively resilient to forest conversion and despite a substantial and consistent change in the soil environment, the effects of conversion differed widely among sites. The substantial difference in soil chemistry, with generally lower nutrient quantity in converted
Bechah, Yassina; Capo, Christian; Mege, Jean-Louis; Raoult, Didier
Epidemic typhus is transmitted to human beings by the body louse Pediculus humanus corporis. The disease is still considered a major threat by public-health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Until recently, Rickettsia prowazekii, the causal agent, was thought to be confined to human beings and their body lice. Since 1975, R prowazekii infection in human beings has been related to contact with the flying squirrel Glaucomys volans in the USA. Moreover, Brill-Zinsser disease, a relapsed form of epidemic typhus that appears as sporadic cases many years after the initial infection, is unrelated to louse infestation. Stress or a waning immune system are likely to reactivate this earlier persistent infection, which could be the source of new epidemics when conditions facilitate louse infestation. Finally, R prowazekii is a potential category B bioterrorism agent, because it is stable in dried louse faeces and can be transmitted through aerosols. An increased understanding of the pathogenesis of epidemic typhus may be useful for protection against this bacterial threat.
Brauer, Fred; Feng, Zhilan; Castillo-Chavez, Carlos
The mathematical theory of single outbreak epidemic models really began with the work of Kermack and Mackendrick about decades ago. This gave a simple answer to the long-standing question of why epidemics woould appear suddenly and then disappear just as suddenly without having infected an entire population. Therefore it seemed natural to expect that theoreticians would immediately proceed to expand this mathematical framework both because the need to handle recurrent single infectious disease outbreaks has always been a priority for public health officials and because theoreticians often try to push the limits of exiting theories. However, the expansion of the theory via the inclusion of refined epidemiological classifications or through the incorporation of categories that are essential for the evaluation of intervention strategies, in the context of ongoing epidemic outbreaks, did not materialize. It was the global threat posed by SARS in that caused theoreticians to expand the Kermack-McKendrick single-outbreak framework. Most recently, efforts to connect theoretical work to data have exploded as attempts to deal with the threat of emergent and re-emergent diseases including the most recent H1N1 influenza pandemic, have marched to the forefront of our global priorities. Since data are collected and/or reported over discrete units of time, developing single outbreak models that fit collected data naturally is relevant. In this note, we introduce a discrete-epidemic framework and highlight, through our analyses, the similarities between single-outbreak comparable classical continuous-time epidemic models and the discrete-time models introduced in this note. The emphasis is on comparisons driven by expressions for the final epidemic size.
Busk, Peter Kamp; Lange, Mette; Pilgaard, Bo
feature as it provides a direct route to predict function from primary sequence. Furthermore, we used Peptide Pattern Recognition to compare the cellulose-degrading enzyme activities encoded by 39 fungal genomes. The results indicated that cellobiohydrolases and AA9 lytic polysaccharide monooxygenases....... In the present study we further developed the method Peptide Pattern Recognition to an automatic approach not only to find all genes encoding glycoside hydrolases and lytic polysaccharide monooxygenases in fungal genomes but also to predict the function of the genes. The functional annotation is an important...
Fungi are ubiquitous in both natural and human-made environments. They play important roles in the health of plants, animals, and humans, and in broad ecosystem functions. Thus, having an efficient species-level identification system could significantly enhance our ability to treat fungal diseases and to monitor the spatial and temporal patterns of fungal distributions and migrations. DNA barcoding is a potent approach for rapid identification of fungal specimens, generating novel species hypothesis, and guiding biodiversity and ecological studies. In this mini-review, I briefly summarize (i) the history of DNA sequence-based fungal identification; (ii) the emergence of the ITS region as the consensus primary fungal barcode; (iii) the use of the ITS barcodes to address a variety of issues on fungal diversity from local to global scales, including generating a large number of species hypothesis; and (iv) the problems with the ITS barcode region and the approaches to overcome these problems. Similar to DNA barcoding research on plants and animals, significant progress has been achieved over the last few years in terms of both the questions being addressed and the foundations being laid for future research endeavors. However, significant challenges remain. I suggest three broad areas of research to enhance the usefulness of fungal DNA barcoding to meet the current and future challenges: (i) develop a common set of primers and technologies that allow the amplification and sequencing of all fungi at both the primary and secondary barcode loci; (ii) compile a centralized reference database that includes all recognized fungal species as well as species hypothesis, and allows regular updates from the research community; and (iii) establish a consensus set of new species recognition criteria based on barcode DNA sequences that can be applied across the fungal kingdom.
Manzano, Marc; Calle, Eusebi; Ripoll, Jordi
Epidemics theory has been used in different contexts in order to describe the propagation of diseases, human interactions or natural phenomena. In computer science, virus spreading has been also characterized using epidemic models. Although in the past the use of epidemic models in telecommunicat......Epidemics theory has been used in different contexts in order to describe the propagation of diseases, human interactions or natural phenomena. In computer science, virus spreading has been also characterized using epidemic models. Although in the past the use of epidemic models...... in telecommunication networks has not been extensively considered, nowadays, with the increasing computation capacity and complexity of operating systems of modern network devices (routers, switches, etc.), the study of possible epidemic-like failure scenarios must be taken into account. When epidemics occur...
... to other illnesses such as the flu or tuberculosis. Some fungal diseases like fungal meningitis and bloodstream ... prevención Fuentes Diagnóstico y pruebas Tratamiento Profesionales de la salud Estadísticas Blastomycosis Definition Symptoms Risk & Prevention Sources ...
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Linders, E.G.A.; Van Damme, J.M.M.; Zadoks, J.C.
Epidemics of the splash-dispersed pathogenic fungus Diaporthe adunca on its host, the perennial herb Plantago lanceolata, were followed during two consecutive years in transects at roadsides in the Netherlands. Epidemics of D. adunca were also studied on clones of a susceptible and a partially
Full Text Available Fungal polyketides are a diverse class of natural products, or secondary metabolites (SMs, with a wide range of bioactivities often associated with toxicity. Here, we focus on a group of non-reducing polyketide synthases (NR-PKSs in the fungal phylum Ascomycota that lack a thioesterase domain for product release, group V. Although widespread in ascomycete taxa, this group of NR-PKSs is notably absent in the mycotoxigenic genus Fusarium and, surprisingly, found in genera not known for their secondary metabolite production (e.g., the mycorrhizal genus Oidiodendron, the powdery mildew genus Blumeria, and the causative agent of white-nose syndrome in bats, Pseudogymnoascus destructans. This group of NR-PKSs, in association with the other enzymes encoded by their gene clusters, produces a variety of different chemical classes including naphthacenediones, anthraquinones, benzophenones, grisandienes, and diphenyl ethers. We discuss the modification of and transitions between these chemical classes, the requisite enzymes, and the evolution of the SM gene clusters that encode them. Integrating this information, we predict the likely products of related but uncharacterized SM clusters, and we speculate upon the utility of these classes of SMs as virulence factors or chemical defenses to various plant, animal, and insect pathogens, as well as mutualistic fungi.
Hite, Jessica L; Penczykowski, Rachel M; Shocket, Marta S; Griebel, Katherine A; Strauss, Alexander T; Duffy, Meghan A; Cáceres, Carla E; Hall, Spencer R
Why do natural populations vary in the frequency of sexual reproduction? Virulent parasites may help explain why sex is favored during disease epidemics. To illustrate, we show a higher frequency of males and sexually produced offspring in natural populations of a facultative parthenogenetic host during fungal epidemics. In a multi-year survey of 32 lakes, the frequency of males (an index of sex) was higher in populations of zooplankton hosts with larger epidemics. A lake mesocosm experiment established causality: experimental epidemics produced a higher frequency of males relative to disease-free controls. One common explanation for such a pattern involves Red Queen (RQ) dynamics. However, this particular system lacks key genetic specificity mechanisms required for the RQ, so we evaluated two other hypotheses. First, individual females, when stressed by infection, could increase production of male offspring vs. female offspring (a tenant of the "Abandon Ship" theory). Data from a life table experiment supports this mechanism. Second, higher male frequency during epidemics could reflect a purely demographic process (illustrated with a demographic model): males could resist infection more than females (via size-based differences in resistance and mortality). However, we found no support for this resistance mechanism. A size-based model of resistance, parameterized with data, revealed why: higher male susceptibility negated the lower exposure (a size-based advantage) of males. These results suggest that parasite-mediated increases in allocation to sex by individual females, rather than male resistance, increased the frequency of sex during larger disease epidemics. © 2017 by the Ecological Society of America.
Paszczyński, Andrzej; Crawford, Ronald L.; Blanchette, Robert A.
Kraft pulps, prepared from softwoods, and small chips of birch wood were treated with heme and tert-butyl hydroperoxide in aqueous solutions at reflux temperature. Analyses of treated pulps showed decreases in kappa number (a measure of lignin content) from about 36 to less than 2, with concomitant increases in brightness (80% increase in the better samples). Analyses of treated wood chips revealed selective delignification and removal of hemicelluloses. After 48 h of treatment, lignin losses from the wood chips approached 40%, and xylose/mannose (hemicellulose) losses approached 70%, while glucose (cellulose) losses were less than 10%. Examination of delignified chips by transmission electron microscopy showed that the removal of lignin occurred in a manner virtually indistinguishable from that seen after decay by white rot fungi. Various metalloporphyrins, which act as biomimetic catalysts, were compared to horseradish peroxidase and fungal manganese peroxidase in their abilities to oxidize syringaldazine in an organic solvent, dioxane. The metalloporphyrins and peroxidases behaved similarly, and it appeared that the activities of the peroxidases resulted from the extraction of heme into the organic phase, rather than from the activities of the enzymes themselves. We concluded that heme-tert-butyl hydroperoxide systems in the absence of a protein carrier mimic the decay of lignified tissues by white rot fungi. Images PMID:16347540
Sonal S Tuli
Full Text Available Sonal S TuliUniversity of Florida, Gainesville, FL, USA Clinical question: What is the most appropriate management of fungal keratitis?Results: Traditionally, topical Natamycin is the most commonly used medication for filamentous fungi while Amphotericin B is most commonly used for yeast. Voriconazole is rapidly becoming the drug of choice for all fungal keratitis because of its wide spectrum of coverage and increased penetration into the cornea.Implementation: Repeated debridement of the ulcer is recommended for the penetration of topical medications. While small, peripheral ulcers may be treated in the community, larger or central ulcers, especially if associated with signs suggestive of anterior chamber penetration should be referred to a tertiary center. Prolonged therapy for approximately four weeks is usually necessary.Keywords: fungal keratitis, keratomycosis, antifungal medications, debridement
Root Fungal Endophytes Enhance Heavy-Metal Stress Tolerance of Clethra barbinervis Growing Naturally at Mining Sites via Growth Enhancement, Promotion of Nutrient Uptake and Decrease of Heavy-Metal Concentration.
Yamaji, Keiko; Watanabe, Yumiko; Masuya, Hayato; Shigeto, Arisa; Yui, Hiroshi; Haruma, Toshikatsu
Clethra barbinervis Sieb. et Zucc. is a tree species that grows naturally at several mine sites and seems to be tolerant of high concentrations of heavy metals, such as Cu, Zn, and Pb. The purpose of this study is to clarify the mechanism(s) underlying this species' ability to tolerate the sites' severe heavy-metal pollution by considering C. barbinervis interaction with root fungal endophytes. We measured the heavy metal concentrations of root-zone soil, leaves, branches, and fine roots collected from mature C. barbinervis at Hitachi mine. We isolated fungal endophytes from surface-sterilized root segments, and we examined the growth, and heavy metal and nutrient absorption of C. barbinervis seedlings growing in sterilized mine soil with or without root fungal endophytes. Field analyses showed that C. barbinervis contained considerably high amounts of Cu, Zn, and Pb in fine roots and Zn in leaves. The fungi, Phialocephala fortinii, Rhizodermea veluwensis, and Rhizoscyphus sp. were frequently isolated as dominant fungal endophyte species. Inoculation of these root fungal endophytes to C. barbinervis seedlings growing in sterilized mine soil indicated that these fungi significantly enhanced the growth of C. barbinervis seedlings, increased K uptake in shoots and reduced the concentrations of Cu, Ni, Zn, Cd, and Pb in roots. Without root fungal endophytes, C. barbinervis could hardly grow under the heavy-metal contaminated condition, showing chlorosis, a symptom of heavy-metal toxicity. Our results indicate that the tree C. barbinervis can tolerate high heavy-metal concentrations due to the support of root fungal endophytes including P. fortinii, R. veluwensis, and Rhizoscyphus sp. via growth enhancement, K uptake promotion and decrease of heavy metal concentrations.
Root Fungal Endophytes Enhance Heavy-Metal Stress Tolerance of Clethra barbinervis Growing Naturally at Mining Sites via Growth Enhancement, Promotion of Nutrient Uptake and Decrease of Heavy-Metal Concentration.
Full Text Available Clethra barbinervis Sieb. et Zucc. is a tree species that grows naturally at several mine sites and seems to be tolerant of high concentrations of heavy metals, such as Cu, Zn, and Pb. The purpose of this study is to clarify the mechanism(s underlying this species' ability to tolerate the sites' severe heavy-metal pollution by considering C. barbinervis interaction with root fungal endophytes. We measured the heavy metal concentrations of root-zone soil, leaves, branches, and fine roots collected from mature C. barbinervis at Hitachi mine. We isolated fungal endophytes from surface-sterilized root segments, and we examined the growth, and heavy metal and nutrient absorption of C. barbinervis seedlings growing in sterilized mine soil with or without root fungal endophytes. Field analyses showed that C. barbinervis contained considerably high amounts of Cu, Zn, and Pb in fine roots and Zn in leaves. The fungi, Phialocephala fortinii, Rhizodermea veluwensis, and Rhizoscyphus sp. were frequently isolated as dominant fungal endophyte species. Inoculation of these root fungal endophytes to C. barbinervis seedlings growing in sterilized mine soil indicated that these fungi significantly enhanced the growth of C. barbinervis seedlings, increased K uptake in shoots and reduced the concentrations of Cu, Ni, Zn, Cd, and Pb in roots. Without root fungal endophytes, C. barbinervis could hardly grow under the heavy-metal contaminated condition, showing chlorosis, a symptom of heavy-metal toxicity. Our results indicate that the tree C. barbinervis can tolerate high heavy-metal concentrations due to the support of root fungal endophytes including P. fortinii, R. veluwensis, and Rhizoscyphus sp. via growth enhancement, K uptake promotion and decrease of heavy metal concentrations.
Mapari, Sameer Shamsuddin; Meyer, Anne S.; Thrane, Ulf
cultivation technology. This approach could secure efficient production of pigments avoiding use of genetic manipulation. Results: Polyketide pigment producing ascomycetous fungi were evaluated for their potential as production organisms based on a priori knowledge on species-specific pigment and potential...... mycotoxin production and BioSafety level (BSL) classification. Based on taxonomic knowledge, we pre-selected ascomycetous fungi belonging to Penicillium subgenus Biverticillium that produced yellow, orange or red pigments while deselecting Penicillium marneffei; a well known human pathogen in addition......Background: Colorants derived from natural sources look set to overtake synthetic colorants in market value as manufacturers continue to meet the rising demand for clean label ingredients-particularly in food applications. Many ascomycetous fungi naturally synthesize and secrete pigments and thus...
Chen, Min; Ma, Yanling; Chen, Huichao; Luo, Hongbing; Dai, Jie; Song, Lijun; Yang, Chaojun; Mei, Jingyuan; Yang, Li; Dong, Lijuan; Jia, Manhong; Lu, Lin
The human immunodeficiency virus 1 (HIV-1) epidemic in China historically stemmed from intravenous drug users (IDUs) in Yunnan. Due to a shared transmission route, hepatitis C virus (HCV)/HIV-1 co-infection is common. Here, we investigated HCV genetic characteristics and baseline drug resistance among HIV-infected IDUs in Yunnan. Blood samples of 432 HIV-1/HCV co-infected IDUs were collected from January to June 2014 in six prefectures of Yunnan Province. Partial E1E2 and NS5B genes were sequenced. Phylogenetic, evolutionary and genotypic drug resistance analyses were performed. Among the 293 specimens successfully genotyped, seven subtypes were identified, including subtypes 3b (37.9%, 111/293), 3a (21.8%, 64/293), 6n (14.0%, 41/293), 1b (10.6%, 31/293), 1a (8.2%, 24/293), 6a (5.1%, 15/293) and 6u (2.4%, 7/293). The distribution of HCV subtypes was mostly related to geographic location. Subtypes 3b, 3a, and 6n were detected in all six prefectures, however, the other four subtypes were detected only in parts of the six prefectures. Phylogeographic analyses indicated that 6n, 1a and 6u originated in the western prefecture (Dehong) and spread eastward and showed genetic relatedness with those detected in Burmese. However, 6a originated in the southeast prefectures (Honghe and Wenshan) bordering Vietnam and was transmitted westward. These subtypes exhibited different evolutionary rates (between 4.35×10-4 and 2.38×10-3 substitutions site-1 year-1) and times of most recent common ancestor (tMRCA, between 1790.3 and 1994.6), suggesting that HCV was multiply introduced into Yunnan. Naturally occurring resistance-associated mutations (C316N, A421V, C445F, I482L, V494A, and V499A) to NS5B polymerase inhibitors were detected in direct-acting antivirals (DAAs)-naïve IDUs. This work reveals the temporal-spatial distribution of HCV subtypes and baseline HCV drug resistance among HIV-infected IDUs in Yunnan. The findings enhance our understanding of the characteristics and
Full Text Available The human immunodeficiency virus 1 (HIV-1 epidemic in China historically stemmed from intravenous drug users (IDUs in Yunnan. Due to a shared transmission route, hepatitis C virus (HCV/HIV-1 co-infection is common. Here, we investigated HCV genetic characteristics and baseline drug resistance among HIV-infected IDUs in Yunnan.Blood samples of 432 HIV-1/HCV co-infected IDUs were collected from January to June 2014 in six prefectures of Yunnan Province. Partial E1E2 and NS5B genes were sequenced. Phylogenetic, evolutionary and genotypic drug resistance analyses were performed.Among the 293 specimens successfully genotyped, seven subtypes were identified, including subtypes 3b (37.9%, 111/293, 3a (21.8%, 64/293, 6n (14.0%, 41/293, 1b (10.6%, 31/293, 1a (8.2%, 24/293, 6a (5.1%, 15/293 and 6u (2.4%, 7/293. The distribution of HCV subtypes was mostly related to geographic location. Subtypes 3b, 3a, and 6n were detected in all six prefectures, however, the other four subtypes were detected only in parts of the six prefectures. Phylogeographic analyses indicated that 6n, 1a and 6u originated in the western prefecture (Dehong and spread eastward and showed genetic relatedness with those detected in Burmese. However, 6a originated in the southeast prefectures (Honghe and Wenshan bordering Vietnam and was transmitted westward. These subtypes exhibited different evolutionary rates (between 4.35×10-4 and 2.38×10-3 substitutions site-1 year-1 and times of most recent common ancestor (tMRCA, between 1790.3 and 1994.6, suggesting that HCV was multiply introduced into Yunnan. Naturally occurring resistance-associated mutations (C316N, A421V, C445F, I482L, V494A, and V499A to NS5B polymerase inhibitors were detected in direct-acting antivirals (DAAs-naïve IDUs.This work reveals the temporal-spatial distribution of HCV subtypes and baseline HCV drug resistance among HIV-infected IDUs in Yunnan. The findings enhance our understanding of the characteristics and
Kozel, Thomas R; Wickes, Brian
Early diagnosis of fungal infection is critical to effective treatment. There are many impediments to diagnosis such as a diminishing number of clinical mycologists, cost, time to result, and requirements for sensitivity and specificity. In addition, fungal diagnostics must meet the contrasting needs presented by the increasing diversity of fungi found in association with the use of immunosuppressive agents in countries with high levels of medical care and the need for diagnostics in resource-limited countries where large numbers of opportunistic infections occur in patients with AIDS. Traditional approaches to diagnosis include direct microscopic examination of clinical samples, histopathology, culture, and serology. Emerging technologies include molecular diagnostics and antigen detection in clinical samples. Innovative new technologies that use molecular and immunoassay platforms have the potential to meet the needs of both resource-rich and resource-limited clinical environments.
Ruepp, Sarah Renée; Fagertun, Anna Manolova
This paper presents the implementation of a failure propagation model for transport networks when multiple failures occur resulting in an epidemic. We model the Susceptible Infected Disabled (SID) epidemic model and validate it by comparing it to analytical solutions. Furthermore, we evaluate...... to evaluate multiple epidemic scenarios in various network types....
Narsing Rao, Manik Prabhu; Xiao, Min; Li, Wen-Jun
The demand for natural colors is increasing day by day due to harmful effects of some synthetic dyes. Bacterial and fungal pigments provide a readily available alternative source of naturally derived pigments. In contrast to other natural pigments, they have enormous advantages including rapid growth, easy processing, and independence of weather conditions. Apart from colorant, bacterial and fungal pigments possess many biological properties such as antioxidant, antimicrobial and anticancer activity. This review outlines different types of pigments. It lists some bacterial and fungal pigments and current bacterial and fungal pigment status and challenges. It also focuses on possible fungal and bacterial pigment applications. PMID:28690593
Manik Prabhu Narsing Rao
Full Text Available The demand for natural colors is increasing day by day due to harmful effects of some synthetic dyes. Bacterial and fungal pigments provide a readily available alternative source of naturally derived pigments. In contrast to other natural pigments, they have enormous advantages including rapid growth, easy processing, and independence of weather conditions. Apart from colorant, bacterial and fungal pigments possess many biological properties such as antioxidant, antimicrobial and anticancer activity. This review outlines different types of pigments. It lists some bacterial and fungal pigments and current bacterial and fungal pigment status and challenges. It also focuses on possible fungal and bacterial pigment applications.
Dombrowski, Kirk; Khan, Bilal; Habecker, Patrick; Hagan, Holly; Friedman, Samuel R; Saad, Mohamed
This article explores how social network dynamics may have reduced the spread of HIV-1 infection among people who inject drugs during the early years of the epidemic. Stochastic, discrete event, agent-based simulations are used to test whether a "firewall effect" can arise out of self-organizing processes at the actor level, and whether such an effect can account for stable HIV prevalence rates below population saturation. Repeated simulation experiments show that, in the presence of recurring, acute, and highly infectious outbreaks, micro-network structures combine with the HIV virus's natural history to reduce the spread of the disease. These results indicate that network factors likely played a significant role in the prevention of HIV infection within injection risk networks during periods of peak prevalence. They also suggest that social forces that disturb network connections may diminish the natural firewall effect and result in higher rates of HIV.
Halliday, Fletcher W; Umbanhowar, James; Mitchell, Charles E
Parasite epidemics may be influenced by interactions among symbionts, which can depend on past events at multiple spatial scales. Within host individuals, interactions can depend on the sequence in which symbionts infect a host, generating priority effects. Across host individuals, interactions can depend on parasite phenology. To test the roles of parasite interactions and phenology in epidemics, we embedded multiple cohorts of sentinel plants, grown from seeds with and without a vertically transmitted symbiont, into a wild host population, and tracked foliar infections caused by three common fungal parasites. Within hosts, parasite growth was influenced by coinfections, but coinfections were often prevented by priority effects among symbionts. Across hosts, parasite phenology altered host susceptibility to secondary infections, symbiont interactions and ultimately the magnitude of parasite epidemics. Together, these results indicate that parasite phenology can influence parasite epidemics by altering the sequence of infection and interactions among symbionts within host individuals. © 2017 John Wiley & Sons Ltd/CNRS.
Maté, Diana; García-Ruiz, Eva; Camarero, Susana; Alcalde, Miguel
Fungal laccases are generalists biocatalysts with potential applications that range from bioremediation to novel green processes. Fuelled by molecular oxygen, these enzymes can act on dozens of molecules of different chemical nature, and with the help of redox mediators, their spectrum of oxidizable substrates is further pushed towards xenobiotic compounds (pesticides, industrial dyes, PAHs), biopolymers (lignin, starch, cellulose) and other complex molecules. In recent years, extraordinary efforts have been made to engineer fungal laccases by directed evolution and semi-rational approaches to improve their functional expression or stability. All these studies have taken advantage of Saccharomyces cerevisiae as a heterologous host, not only to secrete the enzyme but also, to emulate the introduction of genetic diversity through in vivo DNA recombination. Here, we discuss all these endeavours to convert fungal laccases into valuable biomolecular platforms on which new functions can be tailored by directed evolution.
Braunsdorf, C; Mailänder-Sánchez, D; Schaller, M
To survive inside a host, fungi have to adapt to a changing and often hostile environment and therefore need the ability to recognize what is going on around them. To adapt to different host niches, they need to sense external conditions such as temperature, pH and to recognize specific host factors. The ability to respond to physiological changes inside the host, independent of being in a commensal, pathogenic or even symbiotic context, implicates mechanisms for sensing of specific host factors. Because the cell wall is constantly in contact with the surrounding, fungi express receptors on the surface of their cell wall, such as pheromone receptors, which have important roles, besides mediating chemotropism for mating. We are not restricting the discussion to the human host because the receptors and mechanisms used by different fungal species to sense their environment are often similar even for plant pathogens. Furthermore, the natural habitat of opportunistic pathogenic fungi with the potential to cause infection in a human host is in soil and on plants. While the hosts' mechanisms of sensing fungal pathogens have been addressed in the literature, the focus of this review is to fill the gap, giving an overview on fungal sensing of a host-(ile) environment. Expanding our knowledge on host-fungal interactions is extremely important to prevent and treat diseases of pathogenic fungi, which are important issues in human health and agriculture but also to understand the delicate balance of fungal symbionts in our ecosystem. © 2016 John Wiley & Sons Ltd.
Pérez-Reche, Francisco J; Neri, Franco M; Taraskin, Sergei N; Gilligan, Christopher A
Predictability of undesired events is a question of great interest in many scientific disciplines including seismology, economy and epidemiology. Here, we focus on the predictability of invasion of a broad class of epidemics caused by diseases that lead to permanent immunity of infected hosts after recovery or death. We approach the problem from the perspective of the science of complexity by proposing and testing several strategies for the estimation of important characteristics of epidemics, such as the probability of invasion. Our results suggest that parsimonious approximate methodologies may lead to the most reliable and robust predictions. The proposed methodologies are first applied to analysis of experimentally observed epidemics: invasion of the fungal plant pathogen Rhizoctonia solani in replicated host microcosms. We then consider numerical experiments of the susceptible-infected-removed model to investigate the performance of the proposed methods in further detail. The suggested framework can be used as a valuable tool for quick assessment of epidemic threat at the stage when epidemics only start developing. Moreover, our work amplifies the significance of the small-scale and finite-time microcosm realizations of epidemics revealing their predictive power.
An epidemic of acute conjunctivitis in Dar es Salaam in 2010 demonstrated the importance of a strong infectious diseases epidemiological surveillance network to minimise disease outbreaks. Misunderstanding of the causes and management of diseases explains the repetitive nature of acute haemorrhagic conjunctivitis ...
Seeberg, Jens; Christensen, Fie Lund Lindegaard
is skewed in favour of boys, and girls with autism tend to be diagnosed much later than boys. Building and further developing the notion of ‘configuration’ of epidemics, this article explores the configuration of autism in Denmark, with a particular focus on the health system and social support to families...... with children diagnosed with autism, seen from a parental perspective. The article points to diagnostic dynamics that contribute to explaining why girls with autism are not diagnosed as easily as boys. We unfold these dynamics through the analysis of a case of a Danish family with autism.......Autism has been described as an epidemic, but this claim is contested and may point to an awareness epidemic, i.e. changes in the definition of what autism is and more attention being invested in diagnosis leading to a rise in registered cases. The sex ratio of children diagnosed with autism...
Fisher, Matthew C.; Henk, Daniel. A.; Briggs, Cheryl J.; Brownstein, John S.; Madoff, Lawrence C.; McCraw, Sarah L.; Gurr, Sarah J.
The past two decades have seen an increasing number of virulent infectious diseases in natural populations and managed landscapes. In both animals and plants, an unprecedented number of fungal and fungal-like diseases have recently caused some of the most severe die-offs and extinctions ever witnessed in wild species, and are jeopardizing food security. Human activity is intensifying fungal disease dispersal by modifying natural environments and thus creating new opportunities for evolution. ...
Maté, Diana; García-Ruiz, Eva; Camarero, Susana; Alcalde, Miguel
Fungal laccases are generalists biocatalysts with potential applications that range from bioremediation to novel green processes. Fuelled by molecular oxygen, these enzymes can act on dozens of molecules of different chemical nature, and with the help of redox mediators, their spectrum of oxidizable substrates is further pushed towards xenobiotic compounds (pesticides, industrial dyes, PAHs), biopolymers (lignin, starch, cellulose) and other complex molecules. In recent years, extraordinary e...
Learn about obesity and the community initiatives taking place to prevent and reduce this epidemic. Created: 7/18/2011 by National Center for Chronic Disease Prevention and Health Promotion, Division of Nutrition, Physical Activity and Obesity. Date Released: 7/18/2011.
The first peak was related to water contamination which began in December 1990. The second peak was related to failure of municipal authorities to chlorinate water during the 2nd week of February 1991. The epidemic came under control quickly after water contamination was controlled, providing confirmation for role of ...
The first well recorded epidemic was in 1955-56 here in Delhi with nearly 30000 cases. Large outbreaks occurred in 1978 in Kashmir. My interest in this disease began in 1991 during investigations into a large epidemic of hepatitis E in Kanpur that my mentor, later Prof SR Naik, and I undertook. I will use this epidemic as an ...
Brendan D. Snarr
Full Text Available The incidence of fungal infections has dramatically increased in recent years, in large part due to increased use of immunosuppressive medications, as well as aggressive medical and surgical interventions that compromise natural skin and mucosal barriers. There are relatively few currently licensed antifungal drugs, and rising resistance to these agents has led to interest in the development of novel preventative and therapeutic strategies targeting these devastating infections. One approach to combat fungal infections is to augment the host immune response towards these organisms. The polysaccharide-rich cell wall is the initial point of contact between fungi and the host immune system, and therefore, represents an important target for immunotherapeutic approaches. This review highlights the advances made in our understanding of the mechanisms by which the immune system recognizes and interacts with exopolysaccharides produced by four of the most common fungal pathogens: Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, and Histoplasma capsulatum. Work to date suggests that inner cell wall polysaccharides that play an important structural role are the most conserved across diverse members of the fungal kingdom, and elicit the strongest innate immune responses. The immune system senses these carbohydrates through receptors, such as lectins and complement proteins. In contrast, a greater diversity of polysaccharides is found within the outer cell walls of pathogenic fungi. These glycans play an important role in immune evasion, and can even induce anti-inflammatory host responses. Further study of the complex interactions between the host immune system and the fungal polysaccharides will be necessary to develop more effective therapeutic strategies, as well as to explore the use of immunosuppressive polysaccharides as therapeutic agents to modulate inflammation.
Fisher, Matthew C; Henk, Daniel A; Briggs, Cheryl J; Brownstein, John S; Madoff, Lawrence C; McCraw, Sarah L; Gurr, Sarah J
The past two decades have seen an increasing number of virulent infectious diseases in natural populations and managed landscapes. In both animals and plants, an unprecedented number of fungal and fungal-like diseases have recently caused some of the most severe die-offs and extinctions ever witnessed in wild species, and are jeopardizing food security. Human activity is intensifying fungal disease dispersal by modifying natural environments and thus creating new opportunities for evolution. We argue that nascent fungal infections will cause increasing attrition of biodiversity, with wider implications for human and ecosystem health, unless steps are taken to tighten biosecurity worldwide.
Asenova, Elitsa; Lin, Hsin-Yu; Fu, Eileen; Nicolau, Dan V; Nicolau, Dan V
Previous experiments have shown that fungi use an efficient natural algorithm for searching the space available for their growth in micro-confined networks, e.g., mazes. This natural "master" algorithm, which comprises two "slave" sub-algorithms, i.e., collision-induced branching and directional memory, has been shown to be more efficient than alternatives, with one, or the other, or both sub-algorithms turned off. In contrast, the present contribution compares the performance of the fungal natural algorithm against several standard artificial homologues. It was found that the space-searching fungal algorithm consistently outperforms uninformed algorithms, such as Depth-First-Search (DFS). Furthermore, while the natural algorithm is inferior to informed ones, such as A*, this under-performance does not importantly increase with the increase of the size of the maze. These findings suggest that a systematic effort of harvesting the natural space searching algorithms used by microorganisms is warranted and possibly overdue. These natural algorithms, if efficient, can be reverse-engineered for graph and tree search strategies.
Auger, P.; Pouliot, B.; De Grace, M.; Milot, C.; Lafortune, M.; Bergeron, Z.
An outbreak of bacillary dysentery in 1978 affecting 928 persons, most of whom were living in the village of St-Jacques, PQ, is described. An epidemiologic study suggested the water supply as the source of the infection, and it was established that the water carried by the municipal aqueduct was contaminated by feces containing the causal agent, Shigella sonnei. This epidemic, the largest mentioned in he Canadian medical literature, demonstrates how contagious this infection is.
Full Text Available One hundred and seven species of alkalotolerant fungi were isolated from different layers of litter of the Guindy Reserve Forest, Chennai, South India during a 2-year period. They comprised Zygomycota (7 species, Ascomycetes (4 species, hyphomycetes (86 species and coelomycetes (10 species. The F1 litter layer, just beneath the recently fallen leaves, had the richest composition of fungi and the fungi were most abundant during the North East monsoons (September to November. Shannon's diversity index and Simpson diversity index λ indicate F1 layer to have the maximum species. The species distribution fell into the log series model and Fishers alpha was also highest for the F1 layer. Species richness indices computed also indicated that none of the species was more predominant. Values of species evenness computed hovered around 0.6 indicating a tilt towards even distribution of the species. The fungal community is a heterogenous assembly of species derived from a homogenous habitat with a log normal pattern of distribution formed due to the interplay of many independent factors governing the relative abundance of the species. Principal component ordination analysis reveals that the greatest variation in the species composition was due to the South West monsoon. Also, detrended correspondence data put the species abundance data for the four seasons in a linear arrangement.
Cutler, Jim E.; Deepe, George S.; Klein, Bruce S.
The dramatic increase in fungal diseases in recent years can be attributed to the increased aggressiveness of medical therapy and other human activities. Immunosuppressed patients are at risk of contracting fungal diseases in healthcare settings and from natural environments. Increased prescribing of antifungals has led to the emergence of resistant fungi, resulting in treatment challenges. These concerns, together with the elucidation of the mechanisms of protective immunity against fungal d...
The JGI Fungal Genomics Program aims to scale up sequencing and analysis of fungal genomes to explore the diversity of fungi important for energy and the environment, and to promote functional studies on a system level. Combining new sequencing technologies and comparative genomics tools, JGI is now leading the world in fungal genome sequencing and analysis. Over 120 sequenced fungal genomes with analytical tools are available via MycoCosm (www.jgi.doe.gov/fungi), a web-portal for fungal biologists. Our model of interacting with user communities, unique among other sequencing centers, helps organize these communities, improves genome annotation and analysis work, and facilitates new larger-scale genomic projects. This resulted in 20 high-profile papers published in 2011 alone and contributing to the Genomics Encyclopedia of Fungi, which targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts). Our next grand challenges include larger scale exploration of fungal diversity (1000 fungal genomes), developing molecular tools for DOE-relevant model organisms, and analysis of complex systems and metagenomes.
Seyedmousavi, S.; Guillot, J.; Tolooe, A.; Verweij, P.E.; Hoog, G.S. de
Zoonotic fungi can be naturally transmitted between animals and humans, and in some cases cause significant public health problems. A number of mycoses associated with zoonotic transmission are among the group of the most common fungal diseases, worldwide. It is, however, notable that some fungal
Seyedmousavi, S; Guillot, J; Tolooe, A; Verweij, P E; de Hoog, G S
Zoonotic fungi can be naturally transmitted between animals and humans, and in some cases cause significant public health problems. A number of mycoses associated with zoonotic transmission are among the group of the most common fungal diseases, worldwide. It is, however, notable that some fungal
González-Medina, Mariana; Prieto-Martínez, Fernando D; Naveja, J Jesús; Méndez-Lucio, Oscar; El-Elimat, Tamam; Pearce, Cedric J; Oberlies, Nicholas H; Figueroa, Mario; Medina-Franco, José L
Fungi are valuable resources for bioactive secondary metabolites. However, the chemical space of fungal secondary metabolites has been studied only on a limited basis. Herein, we report a comprehensive chemoinformatic analysis of a unique set of 207 fungal metabolites isolated and characterized in a USA National Cancer Institute funded drug discovery project. Comparison of the molecular complexity of the 207 fungal metabolites with approved anticancer and nonanticancer drugs, compounds in clinical studies, general screening compounds and molecules Generally Recognized as Safe revealed that fungal metabolites have high degree of complexity. Molecular fingerprints showed that fungal metabolites are as structurally diverse as other natural products and have, in general, drug-like physicochemical properties. Fungal products represent promising candidates to expand the medicinally relevant chemical space. This work is a significant expansion of an analysis reported years ago for a smaller set of compounds (less than half of the ones included in the present work) from filamentous fungi using different structural properties.
Diamond, R D
In general, fungi are saprophytes that are well adapted to grow in nature supported by diverse nutritional substrates. For fungi, in contrast to many other microorganisms that infect humans, parasitism is an accidental phenomenon rather than an obligatory requirement for survival. Thus, with progressive improvement in our capabilities to prolong survival of patients with global defects in host defense mechanisms, clinical experience suggests that human tissues may support growth of numerous species of saprophytic fungi that share the capacity to grow at 37 degrees C. Normally, however, a broad array of natural and acquired host defense mechanisms make the occurrence of progressive, systemic, life-threatening mycoses extremely rare events. When one or another of these host defense mechanisms is compromised, one of a variety of significant fungal infections may then progress. Mycoses may be broadly categorized into those controlled largely by natural cellular defenses vs. acquired cell-mediated immunity. Notwithstanding data that permit such general classification of host factors controlling one or another invasive mycosis, the diverse structural and antigenic properties of individual fungi create unique patterns of infections in individual, characteristic host settings. Thus, while some broad generalizations are possible, definition of predisposing factors for specific individual mycoses (and, ultimately, prospects for corrective immunotherapy) requires careful characterization of diverse features of fungal forms mediating divergent immune responses.
Associations between plant roots and fungi are a feature of many terrestrial ecosystems. The genome sequence of a prominent fungal partner opens new avenues for studying such mycorrhizal interactions....
... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... touching the infected area. Diagnosis Skin scrapings or cultures Doctors may suspect a fungal infection when they ...
Grigoriev, Igor V.
Genomes of energy and environment fungi are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 50 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such 'parts' suggested by comparative genomics and functional analysis in these areas are presented here
Gras, J R; Lafarga, J; Ronda, J M; Trigueros, M; Sancho, M; Aracil, A
Allergic fungal sinusitis is a recently described clinical entity that has gained increased attention as a cause of chronic sinusitis. Consist in a benign noninvasive sinus disease related to a hypersensitivity reaction to fungal antigens. It should be suspected in any atopic patient with refractory nasal polyps. Computed tomography (CT) findings are characteristics, but not diagnostic. Diagnosis requires show allergic mucin in the histopathologic examination and hiphae in special fungal stains. The suitable treatment includes the allergic mucin removal and sinus aeration accomplished endoscopically, perioperative systemic steroids and immunotherapy with fungal antigens. We present a case of this kind of chronic sinusitis describing the characteristic histopathologic and radiologic findings, the pathogenic theories and recent advances in immunotherapy.
Fungal toenail infection (onychomycosis) is characterised as infection of part or all of the toenail unit, which includes the nail plate, the nail bed, and the nail matrix. Over time, the infection causes discoloration and distortion of part or all of the nail unit. Fungal infections are reported to cause 23% of foot diseases and 50% of nail conditions in people seen by dermatologists, but are less common in the general population, affecting 3% to 12% of people.Infection can cause discomfo...
Fungal toenail infection (onychomycosis) is characterised as infection of part or all of the toenail unit, which includes the nail plate, the nail bed, and the nail matrix. Over time, the infection causes discoloration and distortion of part or all of the nail unit. Fungal infections are reported to cause 23% of foot diseases and 50% of nail conditions in people seen by dermatologists, but are less common in the general population, affecting 3% to 5% of people.Infection can cause discomfor...
Debets, A.J.M.; Dalstra, H.J.P.; Slakhorst, S.M.; Koopmanschap-Memelink, A.B.; Hoekstra, R.F.; Saupe, S.J.
Prions are infectious proteins that cause fatal diseases in mammals. Prions have also been found in fungi, but studies on their role in nature are scarce. The proposed biological function of fungal prions is debated and varies from detrimental to benign or even beneficial. [Het-s] is a prion of the
Notes: We compiled this slide in 1992. It shows dates, locations and number of cases for various epidemics reported from different parts of India till that time. The first well recorded epidemic was in 1955-56 here in Delhi with nearly 30000 cases. Large outbreaks occurred in 1978 in Kashmir. My interest in this disease began ...
Schwensen, Jakob F; Uter, Wolfgang; Bruze, Magnus
BACKGROUND: The use of methylisothiazolinone (MI) in cosmetic products has caused an unprecedented epidemic of MI contact allergy. Current data concerning exposures at a European level are required. OBJECTIVES: To describe demographics and MI exposures for European patients with MI contact allergy....... METHODS: Eleven European dermatology departments from eight European countries prospectively collected data between 1 May and 31 October 2015 among consecutive patients who had positive patch test reactions to MI (2000 ppm aq.). RESULTS: A total of 6.0% (205/3434; range 2.6-13.0%) of patients had positive...... patch test reactions to MI. Dermatitis most frequently affected the hands (43.4%), face (32.7%), arms (14.6%), and eyelids (11.7%); 12.7% had widespread dermatitis. For 72.7% (149/205), MI contact allergy was currently relevant mainly because of exposure to cosmetic products (83.2%; 124...
Ben Achour, N; Benrhouma, H; Rouissi, A; Touaiti, H; Kraoua, I; Turki, I; Gouider-Khouja, N
Rubella is a mild viral illness in children. Rubella encephalitis is an extremely uncommon complication of rubella affecting unvaccinated children, aged between 5 and 14 years. From May to June 2011, we observed 9 cases of rubella encephalitis diagnosed during an epidemic of rubella. All were previously healthy (8 boys and 1 girl). None of them had received rubella vaccine. The mean age was 11.6 years. The onset of neurological symptoms occurred within 1-5 days after the typical rush and was associated with seizures and altered consciousness in all cases. The presence of serum immunoglobulin M antibody against rubella virus was demonstrated in all patients. EEGs showed slow wave activity in all patients and brain MRI was normal in the 9 cases. Full recovery was obtained in all patients. However, 4 of them required intensive care unit referral. Acute encephalitis is an extremely rare complication of rubella. The main neurological findings are headache, ataxia, and hemiplegia. Epileptic seizure and altered consciousness are rarely observed. Rubella encephalitis is generally self-limiting with about 80% recovery rate with no sequelae. However, severe courses have been reported. These cases illustrated the potential severity of rubella and they should be prevented by encouraging widespread early childhood vaccination. In Tunisia, rubella encephalitis has been reported once previously and vaccination against rubella virus has only recently been included in the national vaccination program, prescribed only for adolescent females. Following this rubella epidemic, vaccination strategies in Tunisia have been revised. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
The health condition in Mexico was bad around de beginning of the revolutionary period. The movement of troops led the development of epidemics like yellow fever, typhus, smallpox, and influenza that were enhance with natural disasters and hunger in whole country, from cost to cost and in the north big cities like Monterrey, Guadalajara and Saltillo. Doctor Liceaga conducted a well planned campaign against yellow fever eradicating water stagnant deposits in order to combat the vector transmission, the Aedes aegypti, mosquito with satisfactory results. The first smallpox epidemic in the XX Century in Mexico was in 1916. The Mexican physicians used the smallpox vaccine against this epidemic. An American physician named Howard Taylor Ricketts arrived to Mexico for studying the typhus transmission. Accidentally he had been infected and finally, he died from typhus. Definitively, the epidemics predominate along de revolutionary period in Mexico.
Busby, Posy E; Ridout, Mary; Newcombe, George
Many recent studies have demonstrated that non-pathogenic fungi within plant microbiomes, i.e., endophytes ("endo" = within, "phyte" = plant), can significantly modify the expression of host plant disease. The rapid pace of advancement in endophyte ecology warrants a pause to synthesize our understanding of endophyte disease modification and to discuss future research directions. We reviewed recent literature on fungal endophyte disease modification, and here report on several emergent themes: (1) Fungal endophyte effects on plant disease span the full spectrum from pathogen antagonism to pathogen facilitation, with pathogen antagonism most commonly reported. (2) Agricultural plant pathosystems are the focus of research on endophyte disease modification. (3) A taxonomically diverse group of fungal endophytes can influence plant disease severity. And (4) Fungal endophyte effects on plant disease severity are context-dependent. Our review highlights the importance of fungal endophytes for plant disease across a broad range of plant pathosystems, yet simultaneously reveals that complexity within plant microbiomes presents a significant challenge to disentangling the biotic environmental factors affecting plant disease severity. Manipulative studies integrating eco-evolutionary approaches with emerging molecular tools will be poised to elucidate the functional importance of endophytes in natural plant pathosystems that are fundamental to biodiversity and conservation.
Driessen Arnold JM
Full Text Available Abstract Background The superfamily of ABC proteins is among the largest known in nature. Its members are mainly, but not exclusively, involved in the transport of a broad range of substrates across biological membranes. Many contribute to multidrug resistance in microbial pathogens and cancer cells. The diversity of ABC proteins in fungi is comparable with those in multicellular animals, but so far fungal ABC proteins have barely been studied. Results We performed a phylogenetic analysis of the ABC proteins extracted from the genomes of 27 fungal species from 18 orders representing 5 fungal phyla thereby covering the most important groups. Our analysis demonstrated that some of the subfamilies of ABC proteins remained highly conserved in fungi, while others have undergone a remarkable group-specific diversification. Members of the various fungal phyla also differed significantly in the number of ABC proteins found in their genomes, which is especially reduced in the yeast S. cerevisiae and S. pombe. Conclusions Data obtained during our analysis should contribute to a better understanding of the diversity of the fungal ABC proteins and provide important clues about their possible biological functions.
Fungal toenail infection (onychomycosis) is characterised as infection of part or all of the toenail unit, which includes the nail plate, the nail bed, and the nail matrix. Over time, the infection causes discoloration and distortion of part or all of the nail unit. Fungal infections are reported to cause 23% of foot diseases and 50% of nail conditions in people seen by dermatologists, but are less common in the general population, affecting 3-5% of people.Infection can cause discomfort in...
This paper explores the historical context of the dramatic rise in surgery for glue ear in the mid-20th century, and questions the published assertion that this represented a manufactured 'epidemic'. In examining historical sources, the reader's theoretical viewpoint greatly influences their conclusions: the sustained rise in treatment for glue ear may be seen as the advance of science in a golden age or the resistance of insular professionals to reason in the light of new scientific study methods. Current views on the practice of medicine, consumerism, science and standardisation, rationing and the nature of 'truth' all affect the way that we see this period. Technological advances clearly allowed better diagnosis and more effective treatment, but these did not appear to drive an 'epidemic', rather they were developed to meet the pre-existing challenges of otological practice. The proposition that an 'epidemic' was created does not appear to have any solid grounding. Society's perception of what constitutes disease and what needs treatment may have evolved, but the prevalence of other important diseases changed dramatically over this time period, and a real change in the epidemiology of glue ear cannot be dismissed. In defining the case for and against surgical treatment, a solely positivist, quantitative worldview cannot give us a complete picture of benefit and risk to individuals, families and society at large.
Roy, Manojit; Zinck, Richard D.; Bouma, Menno J.; Pascual, Mercedes
Cholera is on the rise globally, especially epidemic cholera which is characterized by intermittent and unpredictable outbreaks that punctuate periods of regional disease fade-out. These epidemic dynamics remain however poorly understood. Here we examine records for epidemic cholera over both contemporary and historical timelines, from Africa (1990-2006) and former British India (1882-1939). We find that the frequency distribution of outbreak size is fat-tailed, scaling approximately as a power-law. This pattern which shows strong parallels with wildfires is incompatible with existing cholera models developed for endemic regions, as it implies a fundamental role for stochastic transmission and local depletion of susceptible hosts. Application of a recently developed forest-fire model indicates that epidemic cholera dynamics are located above a critical phase transition and propagate in similar ways to aggressive wildfires. These findings have implications for the effectiveness of control measures and the mechanisms that ultimately limit the size of outbreaks.
Jonathan A. Roussey
Full Text Available This review addresses specific regulatory mechanisms involved in the host immune response to fungal organisms. We focus on key cells and regulatory pathways involved in these responses, including a brief overview of their broader function preceding a discussion of their specific relevance to fungal disease. Important cell types discussed include dendritic cells and regulatory T cells, with a focus on specific studies relating to their effects on immune responses to fungi. We highlight the interleukin-10, programmed cell death 1, and cytotoxic T lymphocyte-associated protein 4 signaling pathways and emphasize interrelationships between these pathways and the regulatory functions of dendritic cells and regulatory T cells. Throughout our discussion, we identify selected studies best illustrating the role of these cells and pathways in response to specific fungal pathogens to provide a contextual understanding of the tightly-controlled network of regulatory mechanisms critical to determining the outcome of exposure to fungal pathogens. Lastly, we discuss two unique phenomena relating to immunoregulation, protective tolerance and immune reactivation inflammatory syndrome. These two clinically-relevant conditions provide perspective as to the range of immunoregulatory mechanisms active in response to fungi.
Rick, E M; Woolnough, K; Pashley, C H; Wardlaw, A J
Fungi are ubiquitous and form their own kingdom. Up to 80 genera of fungi have been linked to type I allergic disease, and yet, commercial reagents to test for sensitization are available for relatively few species. In terms of asthma, it is important to distinguish between species unable to grow at body temperature and those that can (thermotolerant) and thereby have the potential to colonize the respiratory tract. The former, which include the commonly studied Alternaria and Cladosporium genera, can act as aeroallergens whose clinical effects are predictably related to exposure levels. In contrast, thermotolerant species, which include fungi from the Candida, Aspergillus, and Penicillium genera, can cause a persistent allergenic stimulus independent of their airborne concentrations. Moreover, their ability to germinate in the airways provides a more diverse allergenic stimulus, and may result in noninvasive infection, which enhances inflammation. The close association between IgE sensitization to thermotolerant filamentous fungi and fixed airflow obstruction, bronchiectasis, and lung fibrosis suggests a much more tissue-damaging process than that seen with aeroallergens. This review provides an overview of fungal allergens and the patterns of clinical disease associated with exposure. It clarifies the various terminologies associated with fungal allergy in asthma and makes the case for a new term (allergic fungal airway disease) to include all people with asthma at risk of developing lung damage as a result of their fungal allergy. Lastly, it discusses the management of fungirelated asthma.
Rattaket Choeyklin; Souwalak Phongpaichit; Ittichai Chatmala; Jariya Sakayaroj; Apiradee Pilantanapak; E.B. Gareth Jones
The marine fungal diversity of Thailand was investigated and 116 Ascomycota, 3 Basidiomycota, 28 anamorphic fungi, 7 Stramenopiles recorded, with 30 tentatively identified. These species have primarily been collected from driftwood and attached decayed wood of mangrove trees. The holotype number of 15 taxa is from Thailand and 33 are new records from the country.
Full Text Available The marine fungal diversity of Thailand was investigated and 116 Ascomycota, 3 Basidiomycota, 28 anamorphic fungi, 7 Stramenopiles recorded, with 30 tentatively identified. These species have primarily been collected from driftwood and attached decayed wood of mangrove trees. The holotype number of 15 taxa is from Thailand and 33 are new records from the country.
Heitman, Joseph; Howlett, B.J.; Crous, P.W.; Stukenbrock, E.H.; James, T.Y.; Gow, N.A.R.
Fungi research and knowledge grew rapidly following recent advances in genetics and genomics. This book synthesizes new knowledge with existing information to stimulate new scientific questions and propel fungal scientists on to the next stages of research. This book is a comprehensive guide on
Dr. David Tribble, acting director of the infectious disease clinical research program at Uniformed Services University of the Health Sciences, discusses fungal wound infections after combat trauma. Created: 1/28/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 1/28/2016.
Scheel, Jan Frederik; Kunert, Anna Theresa; Kampf, Christopher Johannes; Mauri, Sergio; Weidner, Tobias; Pöschl, Ulrich; Fröhlich-Nowoisky, Janine
Freezing of water at relatively warm subfreezing temperatures is dependent on ice nucleation catalysis facilitated by ice nuclei (IN). These IN can be of various origins and although extensive research was done and progress was achieved, the nature and mechanisms leading to an effective IN are to date still poorly understood. Some of the most important processes of our geosphere like the water cycle are highly dependent on effective ice nucleation at temperatures between -2°C - -8°C, a temperature range which is almost exclusively covered by biological IN (BioIN). BioIN are usually macromolecular structures of biological polymers. Sugars as well as proteins have been reported to serve as IN and the best characterized BioIN are ice nucleation proteins (IN-P) from gram negative bacteria. Fungal strains from Fusarium spp. were described to be effective IN at subfreezing temperatures up to -2°C already 25 years ago and more and more fungal species are described to serve as efficient IN. Fungal IN are also thought to be proteins or at least contain a proteinaceous compound, but to date the fungal IN-P primary structure as well as their coding genetic elements of all IN active fungi are unknown. The aim of this study is a.) to identify the proteins and their coding genetic elements from IN active fungi (F. acuminatum, F. avenaceum, M. alpina) and b.) to characterize the mechanisms by which fungal IN serve as effective IN. We designed an interdisciplinary approach using biological, analytical and physical methods to identify fungal IN-P and describe their biological, chemical, and physical properties.
Durairaj, Pradeepraj; Hur, Jae-Seoun; Yun, Hyungdon
Cytochrome P450 (CYP) monooxygenases, the nature's most versatile biological catalysts have unique ability to catalyse regio-, chemo-, and stereospecific oxidation of a wide range of substrates under mild reaction conditions, thereby addressing a significant challenge in chemocatalysis. Though CYP enzymes are ubiquitous in all biological kingdoms, the divergence of CYPs in fungal kingdom is manifold. The CYP enzymes play pivotal roles in various fungal metabolisms starting from housekeeping biochemical reactions, detoxification of chemicals, and adaptation to hostile surroundings. Considering the versatile catalytic potentials, fungal CYPs has gained wide range of attraction among researchers and various remarkable strategies have been accomplished to enhance their biocatalytic properties. Numerous fungal CYPs with multispecialty features have been identified and the number of characterized fungal CYPs is constantly increasing. Literature reveals ample reviews on mammalian, plant and bacterial CYPs, however, modest reports on fungal CYPs urges a comprehensive review highlighting their novel catalytic potentials and functional significances. In this review, we focus on the diversification and functional diversity of fungal CYPs and recapitulate their unique and versatile biocatalytic properties. As such, this review emphasizes the crucial issues of fungal CYP systems, and the factors influencing efficient biocatalysis.
Bladt, Tanja Thorskov; Kildgaard, Sara; Knudsen, Peter Boldsen
Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults from the western world. No curative treatments of CLL are presently known so the treatment strategy today is primarily to prolong patient survival,1 why we have initiated new activities towards discovery of novel compounds w...
Bladt, Tanja Thorskov; Kildgaard, Sara; Knudsen, Peter Boldsen
Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults from the western world. No curative treatments of CLL are presently known so the treatment strategy today is primarily to prolong patient survival,1 why we have initiated new activities towards discovery of novel compounds......,3 This includes analysis of the spectroscopic data generated from LC-DAD-MS to reveal whether the active principles are either structurally known compounds or are likely to be novel compounds. This paper will illustrate our integrated discovery approaches and recent findings of anti-leukemia compounds....
Sadun, A A; Martone, J F; Muci-Mendoza, R; Reyes, L; DuBois, L; Silva, J C; Roman, G; Caballero, B
, economic, and social changes in Cuba may have contributed to the nutritional and/or toxic compromise of mitochondrial function of an acquired nature, which led to selective retinal ganglion cell damage. We have termed this condition Cuban epidemic optic neuropathy.
Full Text Available South Africa is experiencing an explosive epidemic of HIV/AIDS, with about one in four women attending ante-natal clinics nation-wide being HIV-positive. In order to understand the natural history of the epidemic, to design and target intervention...
Crawford, Andrew J.; Lips, Karen R.; Bermingham, Eldredge
Amphibian populations around the world are experiencing unprecedented declines attributed to a chytrid fungal pathogen, Batrachochytrium dendrobatidis. Despite the severity of the crisis, quantitative analyses of the effects of the epidemic on amphibian abundance and diversity have been unavailable as a result of the lack of equivalent data collected before and following disease outbreak. We present a community-level assessment combining long-term field surveys and DNA barcode data describing...
Pastor-Satorras, Romualdo; Castellano, Claudio; Van Mieghem, Piet; Vespignani, Alessandro
In recent years the research community has accumulated overwhelming evidence for the emergence of complex and heterogeneous connectivity patterns in a wide range of biological and sociotechnical systems. The complex properties of real-world networks have a profound impact on the behavior of equilibrium and nonequilibrium phenomena occurring in various systems, and the study of epidemic spreading is central to our understanding of the unfolding of dynamical processes in complex networks. The theoretical analysis of epidemic spreading in heterogeneous networks requires the development of novel analytical frameworks, and it has produced results of conceptual and practical relevance. A coherent and comprehensive review of the vast research activity concerning epidemic processes is presented, detailing the successful theoretical approaches as well as making their limits and assumptions clear. Physicists, mathematicians, epidemiologists, computer, and social scientists share a common interest in studying epidemic spreading and rely on similar models for the description of the diffusion of pathogens, knowledge, and innovation. For this reason, while focusing on the main results and the paradigmatic models in infectious disease modeling, the major results concerning generalized social contagion processes are also presented. Finally, the research activity at the forefront in the study of epidemic spreading in coevolving, coupled, and time-varying networks is reported.
Kakeya, Hiroshi; Kohno, Shigeru
Proven fungal infections are diagnosed by histological/microbiological evidence of fungi at the site of infection and positive blood culture (fungemia). However, invasive diagnosing examinations are not always applied for all of immunocompromised patients. Clinically documented invasive fungal infections are diagnosed by typical radiological findings such as halo sign on chest CT plus positive serological/molecular evidence of fungi. Serological tests of Aspergillus galactomannan antigen and beta-glucan for aspergillosis and cryptococcal glucuronoxylomannan antigen for cryptococcosis are useful. Hence, none of reliable serological tests for zygomycosis are available so far. In this article, risk factors, sign and symptoms, and diagnostic methods for clinically documented cases of invasive aspergillosis, pulmonary cryptococcosis, and zygomycosis with diabates, are reviewed.
Kelly, Brendan P
Tinea capitis, tinea corporis, and pityriasis versicolor are common superficial fungal infections in the pediatric population. • Tinea capitis is the most common dermatophyte infection worldwide. In North America, the cause is almost exclusively T tonsurans. Diagnosis of tinea capitis usually can be made by clinical features alone, especially when occipital or postauricular lymphadenopathy is present. Skin scrapings prepared with potassium hydroxide for microscopic examination, or a cotton swab for fungal culture, usually are diagnostic. • Treatment of tinea capitis requires systemic antifungal therapy. Terbinafine and griseofulvin are both effective against T tonsurans and are FDA-approved for this indication in children. • Adjunctive topical therapy for the patient and household contacts decreases transmission of this infection. • Topical antifungal therapy usually is effective for tinea corporis and pityriasis versicolor. However, recurrences of pityriasis versicolor are common.
Gerwien, Franziska; Skrahina, Volha; Kasper, Lydia; Hube, Bernhard; Brunke, Sascha
Metals are essential for life, and they play a central role in the struggle between infecting microbes and their hosts. In fact, an important aspect of microbial pathogenesis is the 'nutritional immunity', in which metals are actively restricted (or, in an extended definition of the term, locally enriched) by the host to hinder microbial growth and virulence. Consequently, fungi have evolved often complex regulatory networks, uptake and detoxification systems for essential metals such as iron, zinc, copper, nickel and manganese. These systems often differ fundamentally from their bacterial counterparts, but even within the fungal pathogens we can find common and unique solutions to maintain metal homeostasis. Thus, we here compare the common and species-specific mechanisms used for different metals among different fungal species-focusing on important human pathogens such as Candida albicans, Aspergillus fumigatus or Cryptococcus neoformans, but also looking at model fungi such as Saccharomyces cerevisiae or A. nidulans as well-studied examples for the underlying principles. These direct comparisons of our current knowledge reveal that we have a good understanding how model fungal pathogens take up iron or zinc, but that much is still to learn about other metals and specific adaptations of individual species-not the least to exploit this knowledge for new antifungal strategies. © FEMS 2017.
Ghabrial, Said A., E-mail: firstname.lastname@example.org [Plant Pathology Department, University of Kentucky, Lexington, KY (United States); Castón, José R. [Department of Structure of Macromolecules, Centro Nacional Biotecnologıa/CSIC, Campus de Cantoblanco, Madrid (Spain); Jiang, Daohong [State Key Lab of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei Province (China); Nibert, Max L. [Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA (United States); Suzuki, Nobuhiro [Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama (Japan)
Mycoviruses are widespread in all major taxa of fungi. They are transmitted intracellularly during cell division, sporogenesis, and/or cell-to-cell fusion (hyphal anastomosis), and thus their life cycles generally lack an extracellular phase. Their natural host ranges are limited to individuals within the same or closely related vegetative compatibility groups, although recent advances have established expanded experimental host ranges for some mycoviruses. Most known mycoviruses have dsRNA genomes packaged in isometric particles, but an increasing number of positive- or negative-strand ssRNA and ssDNA viruses have been isolated and characterized. Although many mycoviruses do not have marked effects on their hosts, those that reduce the virulence of their phytopathogenic fungal hosts are of considerable interest for development of novel biocontrol strategies. Mycoviruses that infect endophytic fungi and those that encode killer toxins are also of special interest. Structural analyses of mycoviruses have promoted better understanding of virus assembly, function, and evolution. - Highlights: • Historical perspective of fungal virus research. • Description, classification and diversity of fungal virus families. • Structural features of fungal virus particles. • Hypovirulence and exploitation of mycoviruses in biological control of plant pathogenic fungi.
Navaud, Olivier; Barbacci, Adelin; Taylor, Andrew; Clarkson, John P; Raffaele, Sylvain
The range of hosts that a parasite can infect in nature is a trait determined by its own evolutionary history and that of its potential hosts. However, knowledge on host range diversity and evolution at the family level is often lacking. Here, we investigate host range variation and diversification trends within the Sclerotiniaceae, a family of Ascomycete fungi. Using a phylogenetic framework, we associate diversification rates, the frequency of host jump events and host range variation during the evolution of this family. Variations in diversification rate during the evolution of the Sclerotiniaceae define three major macro-evolutionary regimes with contrasted proportions of species infecting a broad range of hosts. Host-parasite cophylogenetic analyses pointed towards parasite radiation on distant hosts long after host speciation (host jump or duplication events) as the dominant mode of association with plants in the Sclerotiniaceae. The intermediate macro-evolutionary regime showed a low diversification rate, high frequency of duplication events and the highest proportion of broad host range species. Our findings suggest that the emergence of broad host range fungal pathogens results largely from host jumps, as previously reported for oomycete parasites, probably combined with low speciation rates. These results have important implications for our understanding of fungal parasites evolution and are of particular relevance for the durable management of disease epidemics. © 2018 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.
We study a susceptible-infected-susceptible epidemic process over a static contact network where the nodes have partial information about the epidemic state. They react by limiting their interactions with their neighbors when they believe the epidemic is currently prevalent. A node\\'s awareness is weighted by the fraction of infected neighbors in their social network, and a global broadcast of the fraction of infected nodes in the entire network. The dynamics of the benchmark (no awareness) and awareness models are described by discrete-time Markov chains, from which mean-field approximations (MFAs) are derived. The states of the MFA are interpreted as the nodes\\' probabilities of being infected. We show a sufficient condition for the existence of a
Azaele, Sandro; Maritan, Amos; Bertuzzo, Enrico; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea
We describe the predictions of an analytically tractable stochastic model for cholera epidemics following a single initial outbreak. The exact model relies on a set of assumptions that may restrict the generality of the approach and yet provides a realm of powerful tools and results. Without resorting to the depletion of susceptible individuals, as usually assumed in deterministic susceptible-infected-recovered models, we show that a simple stochastic equation for the number of ill individuals provides a mechanism for the decay of the epidemics occurring on the typical time scale of seasonality. The model is shown to provide a reasonably accurate description of the empirical data of the 2000/2001 cholera epidemic which took place in the Kwa Zulu-Natal Province, South Africa, with possibly notable epidemiological implications.
Jutla, Antarpreet; Whitcombe, Elizabeth; Hasan, Nur; Haley, Bradd; Akanda, Ali; Huq, Anwar; Alam, Munir; Sack, R. Bradley; Colwell, Rita
Cholera outbreak following the earthquake of 2010 in Haiti has reaffirmed that the disease is a major public health threat. Vibrio cholerae is autochthonous to aquatic environment, hence, it cannot be eradicated but hydroclimatology-based prediction and prevention is an achievable goal. Using data from the 1800s, we describe uniqueness in seasonality and mechanism of occurrence of cholera in the epidemic regions of Asia and Latin America. Epidemic regions are located near regional rivers and are characterized by sporadic outbreaks, which are likely to be initiated during episodes of prevailing warm air temperature with low river flows, creating favorable environmental conditions for growth of cholera bacteria. Heavy rainfall, through inundation or breakdown of sanitary infrastructure, accelerates interaction between contaminated water and human activities, resulting in an epidemic. This causal mechanism is markedly different from endemic cholera where tidal intrusion of seawater carrying bacteria from estuary to inland regions, results in outbreaks. PMID:23897993
Ben-Naim, E.; Krapivsky, P. L.
We study the classic Susceptible-Infected-Recovered (SIR) model for the spread of an infectious disease. In this stochastic process, there are two competing mechanism: infection and recovery. Susceptible individuals may contract the disease from infected individuals, while infected ones recover from the disease at a constant rate and are never infected again. Our focus is the behavior at the epidemic threshold where the rates of the infection and recovery processes balance. In the infinite population limit, we establish analytically scaling rules for the time-dependent distribution functions that characterize the sizes of the infected and the recovered sub-populations. Using heuristic arguments, we also obtain scaling laws for the size and duration of the epidemic outbreaks as a function of the total population. We perform numerical simulations to verify the scaling predictions and discuss the consequences of these scaling laws for near-threshold epidemic outbreaks.
García de León, David; Davison, John; Moora, Mari; Öpik, Maarja; Feng, Huyuan; Hiiesalu, Inga; Jairus, Teele; Koorem, Kadri; Liu, Yongjun; Phosri, Cherdchai; Sepp, Siim-Kaarel; Vasar, Martti; Zobel, Martin
The arbuscular mycorrhizal (AM) symbiosis is a key plant-microbe interaction in sustainable functioning ecosystems. Increasing anthropogenic disturbance poses a threat to AM fungal communities worldwide, but there is little empirical evidence about its potential negative consequences. In this global study we sequenced AM fungal DNA in soil samples collected from pairs of natural (undisturbed) and anthropogenic (disturbed) plots in two ecosystem types (ten naturally wooded and six naturally unwooded ecosystems). We found that ecosystem type had stronger directional effects than anthropogenic disturbance on AM fungal alpha and beta diversity. However, disturbance increased alpha and beta diversity at sites where natural diversity was low, and decreased diversity at sites where natural diversity was high. Cultured AM fungal taxa were more prevalent in anthropogenic than natural plots, probably due to their efficient colonization strategies and ability to recover from disturbance. We conclude that anthropogenic disturbance does not have a consistent directional effect on AM fungal diversity; rather, disturbance equalizes levels of diversity at large scales and causes changes in community functional structure. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Mitchell, Nia; Catenacci, Vicki; Wyatt, Holly R.; Hill, James O.
Despite growing recognition of the problem, the obesity epidemic continues in the U.S., and obesity rates are increasing around the world. The latest estimates are that approximately 34% of adults and 15–20% of children and adolescents in the U.S. are obese. Obesity affects every segment of the U.S. population. Obesity increases the risk of many chronic diseases in children and adults. The epidemic of obesity arose gradually over time, apparently from a small, consistent degree of positive en...
Wetzel, Eunike; Brown, Anna; Hill, Patrick; Chung, J.M.H.; Robins, R.W.; Roberts, B.W.
Are recent cohorts of college students more narcissistic than their predecessors? To address debates about the so-called “narcissism epidemic,” we used data from three cohorts of students (N1990s = 1,166; N2000s = 33,647; N2010s = 25,412) to test whether narcissism levels (overall and specific
Aug 26, 2014 ... Method: 'Know your epidemic' synthesis suggests that HIV prevalence is rising in older age groups and falling in younger people. Using secondary data analyses of population-based and antenatal care surveillance (ANC) surveys, we explored trends and patterns in HIV prevalence in KwaZulu-Natal and ...
Read, D J; Ducket, J G; Francis, R; Ligron, R; Russell, A
these plants are similar to those seen in mycorrhizal associations of ericaceous plants like Vaccinium. Cross inoculation experiments have confirmed that a typical mycorrhizal endophyte of ericaceous plants, Hymenoscyphus ericae, will form associations in liverworts which are structurally identical to those seen in nature. Again, the functional significance of these associations remains to be examined. Some members of the Jungermanniales and Metzgeriales form associations with basidiomycetous fungi. These produce intracellular coils of hyphae, which are similar to the pelotons seen in orchid mycorrhizas, which also involve basidiomycetes. The fungal associates of the autotrophic Aneura and of its heterotrophic relative Cryptothallus mirabilis have been isolated. In the latter case it has been shown that the fungal symbiont is an ectomycorrhizal associate of Betula, suggesting that the apparently obligate nature of the association between the hepatic and Betula in nature is based upon requirement for this particular heterotroph.
Lefèvre, Claude; Picard, Philippe
This collection of papers gives a representative cross-selectional view of recent developments in the field. After a survey paper by C. Lefèvre, 17 other research papers look at stochastic modeling of epidemics, both from a theoretical and a statistical point of view. Some look more specifically at a particular disease such as AIDS, malaria, schistosomiasis and diabetes.
Schiøler, Henrik; Nielsen, Jens Frederik Dalsgaard; Ngo, Trung Dung
Clock synchronization in swarms of networked mobile robots is studied in a probabilistic, epidemic framework. In this setting communication and synchonization is considered to be a randomized process, taking place at unplanned instants of geographical rendezvous between robots. In combination...... as an infinite-dimensional optimal controlproblem. Illustrative numerical examples are given and commented....
Courtwright, David T.
Discusses the wave of cocaine abuse that followed the drug's recommendation by the late nineteenth-century medical community as a cure all. Details drug addiction among ethnic and social groups at the turn of the century. Warns that drug epidemics have important social and legal consequences. Suggests legal pressure may alter the form of drug…
... About the Epidemic Help, Resources and Information National Opioids Crisis Search Search National Helpline SAMHSA’s National Helpline ... 1-800-662-4357 Visit Helpline Website THE OPIOID EPIDEMIC IN NUMBERS 80% Nearly 80% of heroin ...
Ledbetter, Eric C; Norman, Mary L; Starr, Jennifer K
To describe in vivo corneal confocal microscopy of dogs during the clinical course of fungal keratitis and correlate findings with clinical evaluations and an ex vivo experimental canine fungal keratitis model. Seven dogs with naturally acquired fungal keratitis and ex vivo canine corneas experimentally infected with clinical fungal isolates. Dogs with naturally acquired fungal keratitis were examined by in vivo laser scanning confocal microscopy. Initial confocal microscopic examinations were performed to assist in establishing the diagnosis of fungal keratitis. Serial confocal microscopic examinations were performed to guide antifungal chemotherapy. Confocal microscopy images of canine corneal fungal isolates were obtained by examination of experimentally infected ex vivo canine corneas to corroborate in vivo findings. Fungi cultured and detected by PCR from canine corneal samples included Candida albicans, Fusarium incarnatum-equiseti, Malassezia pachydermatis, and a Rhodotorula sp. Linear, branching, interlocking, hyperreflective structures were detected by confocal microscopy in dogs with filamentous fungal keratitis and round to oval hyperreflective structures were detected in dogs with yeast fungal keratitis. Antifungal chemotherapy was associated with a progressive reduction in the distribution and density of corneal fungal elements, alterations to fungal morphology, decreased leukocyte numbers, restoration of epithelial layers, and an increased number of visible keratocyte nuclei. No dogs had a recurrence of fungal keratitis following medication discontinuation. Confocal microscopic fungal morphologies were similar between in vivo and ex vivo examinations. In vivo corneal confocal microscopy is a rapid method of diagnosing fungal keratitis in dogs and provides a noninvasive mechanism for monitoring therapeutic response. © 2015 American College of Veterinary Ophthalmologists.
Elías Gómez Macías
Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.
Full Text Available The question as to why parasites remain generalist or become specialist is a key unresolved question in evolutionary biology. Ampelomyces spp., intracellular mycoparasites of powdery mildew fungi, which are themselves plant pathogens, are a useful model for studies of this issue. Ampelomyces is used for the biological control of mildew. Differences in mycohost phenology promote temporal isolation between sympatric Ampelomyces mycoparasites. Apple powdery mildew (APM causes spring epidemics, whereas other powdery mildew species on plants other than apple cause epidemics later in the season. This has resulted in genetic differentiation between APM and non-APM strains. It is unclear whether there is genetic differentiation between non-APM Ampelomyces lineages due to their specialization on different mycohosts. We used microsatellites to address this question and found no significant differentiation between non-APM Ampelomyces strains from different mycohosts or host plants, but strong differentiation between APM and non-APM strains. A geographical structure was revealed in both groups, with differences between European countries, demonstrating restricted dispersal at the continent scale and a high resolution for our markers. We found footprints of recombination in both groups, possibly more frequent in the APM cluster. Overall, Ampelomyces thus appears to be one of the rare genuine generalist pathogenic fungi able to parasitize multiple hosts in natural populations. It is therefore an excellent model for studying the evolution of pathogens towards a generalist rather than host-specific strategy, particularly in light of the tritrophic interaction between Ampelomyces mycoparasites, their powdery mildew fungal hosts and the mildew host plants.
Télesphore eSIME - NGANDO
Full Text Available Parasitism is one of the earlier and common ecological interactions in the nature, occurring in almost all environments. Microbial parasites typically are characterized by their small size, short generation time, and high rates of reproduction, with simple life cycle occurring generally within a single host. They are diverse and ubiquitous in aquatic ecosystems, comprising viruses, prokaryotes and eukaryotes. Recently, environmental 18S-rDNA surveys of microbial eukaryotes have unveiled major infecting agents in pelagic systems, consisting primarily of the fungal order of Chytridiales (chytrids. Chytrids are considered the earlier branch of the Eumycetes and produce motile, flagellated zoospores, characterized by a small size (2-6 µm and a single, posterior flagellum. The existence of these dispersal propagules includes chytrids within the so-called group of zoosporic fungi, which are particularly adapted to the plankton lifestyle where they infect a wide variety of hosts, including fishes, eggs, zooplankton, algae, and other aquatic fungi but primarily freshwater phytoplankton. Related ecological implications are huge because chytrids can killed their hosts, release substrates for microbial processes, and provide nutrient-rich particles as zoospores and short fragments of filamentous inedible hosts for the grazer food chain. Furthermore, based on the observation that phytoplankton chytridiomycosis preferentially impacts the larger size species, blooms of such species (e.g. filamentous cyanobacteria may not totally represent trophic bottlenecks. Besides, chytrid epidemics represent an important driving factor in phytoplankton seasonal successions. In this review, I summarize the knowledge on the diversity, community structure, quantitative importance, and functional roles of fungal chytrids, primarily those who are parasites of phytoplankton, and infer the ecological implications and potentials for the food web dynamics and properties.
Chambergo, Felipe S; Valencia, Estela Y
Fungal habitats include soil, water, and extreme environments. With around 100,000 fungus species already described, it is estimated that 5.1 million fungus species exist on our planet, making fungi one of the largest and most diverse kingdoms of eukaryotes. Fungi show remarkable metabolic features due to a sophisticated genomic network and are important for the production of biotechnological compounds that greatly impact our society in many ways. In this review, we present the current state of knowledge on fungal biodiversity, with special emphasis on filamentous fungi and the most recent discoveries in the field of identification and production of biotechnological compounds. More than 250 fungus species have been studied to produce these biotechnological compounds. This review focuses on three of the branches generally accepted in biotechnological applications, which have been identified by a color code: red, green, and white for pharmaceutical, agricultural, and industrial biotechnology, respectively. We also discuss future prospects for the use of filamentous fungi in biotechnology application.
Hongsanan, S.; Sánchez-Ramírez, S.; Crous, P.W.; Ariyawansa, H.A.; Zhao, R.L.; Hyde, K.D.
Fungal epiphytes are a polyphyletic group found on the surface of plants, particularly on leaves, with a worldwide distribution. They belong in the phylum Ascomycota, which contains the largest known number of fungal genera. There has been little research dating the origins of the common ancestors
Meis, J.F.G.M.; Verweij, P.E.
The management of superficial fungal infections differs significantly from the management of systemic fungal infections. Most superficial infections are treated with topical antifungal agents, the choice of agent being determined by the site and extent of the infection and by the causative organism,
... Care Med 1998;24:206-16. Alangaden GJ. Nosocomial Fungal Infections: Epidemiology, Infection Control, and Prevention. Infectious Disease Clinics ... 25:201-25. Zilberberg MD, Shorr AF. Fungal infections in the ICU. Infect Dis ... D. Nosocomial aspergillosis and building construction. Med Mycol 2009;47 ...
Jabeen, K; Farooqi, J; Mirza, S; Denning, D; Zafar, A
The true burden of fungal infection in Pakistan is unknown. High-risk populations for fungal infections [tuberculosis (TB), diabetes, chronic respiratory diseases, asthma, cancer, transplant and human immunodeficiency virus (HIV) infection] are numerous. Here, we estimate the burden of fungal infections to highlight their public health significance. Whole and at-risk population estimates were obtained from the WHO (TB), BREATHE study (COPD), UNAIDS (HIV), GLOBOCAN (cancer) and Heartfile (diabetes). Published data from Pakistan reporting fungal infections rates in general and specific populations were reviewed and used when applicable. Estimates were made for the whole population or specific populations at risk, as previously described in the LIFE methodology. Of the 184,500,000 people in Pakistan, an estimated 3,280,549 (1.78%) are affected by a serious fungal infection, omitting all cutaneous infection, oral candidiasis and allergic fungal sinusitis, which we could not estimate. Compared with other countries, the rates of candidaemia (21/100,000) and mucormycosis (14/100,000) are estimated to be very high, and are based on data from India. Chronic pulmonary aspergillosis rates are estimated to be high (39/100,000) because of the high TB burden. Invasive aspergillosis was estimated to be around 5.9/100,000. Fungal keratitis is also problematic in Pakistan, with an estimated rate of 44/100,000. Pakistan probably has a high rate of certain life- or sight-threatening fungal infections.
Sharma, Alaisha; Galazka, Jonathan (Editor)
Fungi can synthesize numerous molecules with important properties, and could be valuable production platforms for space exploration and colonization. However, as heterotrophs, fungi require reduced carbon. This limits their efficiency in locations such as Mars, where reduced carbon is scarce. We propose a system to induce mutualistic symbiosis between the green algae Chlamydomonas reinhardtii and the filamentous fungi Neurospora crassa. This arrangement would mimic natural algal-fungal relationships found in lichens, but have added advantages including increased growth rate and genetic tractability. N. crassa would metabolize citrate (C6H5O7 (sup -3)) and release carbon dioxide (CO2) that C. reinhardtii would assimilate into organic sugars during photosynthesis. C. reinhardtii would metabolize nitrate (NO3-) and release ammonia (NH3) as a nitrogen source for N. crassa. A N. crassa mutant incapable of reducing nitrate will be used to force this interaction. This system eliminates the need to directly supply its participants with carbon dioxide and ammonia. Furthermore, the release of oxygen by C. reinhardtii via photosynthesis would enable N. crassa to respire. We hope to eventually create a system closer to lichen, in which the algae transfers not only nitrogen but reduced carbon, as organic sugars, to the fungus for growth and production of valuable compounds.
Hernández, D. G.; Risau-Gusman, S.
It is well known that sexually transmitted diseases (STD) spread across a network of human sexual contacts. This network is most often bipartite, as most STD are transmitted between men and women. Even though network models in epidemiology have quite a long history now, there are few general results about bipartite networks. One of them is the simple dependence, predicted using the mean field approximation, between the epidemic threshold and the average and variance of the degree distribution of the network. Here we show that going beyond this approximation can lead to qualitatively different results that are supported by numerical simulations. One of the new features, that can be relevant for applications, is the existence of a critical value for the infectivity of each population, below which no epidemics can arise, regardless of the value of the infectivity of the other population.
Zhao, Dawei; Li, Lixiang; Peng, Haipeng; Luo, Qun; Yang, Yixian
This letter investigates the multiple routes transmitted epidemic process on multiplex networks. We propose detailed theoretical analysis that allows us to accurately calculate the epidemic threshold and outbreak size. It is found that the epidemic can spread across the multiplex network even if all the network layers are well below their respective epidemic thresholds. Strong positive degree–degree correlation of nodes in multiplex network could lead to a much lower epidemic threshold and a relatively smaller outbreak size. However, the average similarity of neighbors from different layers of nodes has no obvious effect on the epidemic threshold and outbreak size. -- Highlights: •We studies multiple routes transmitted epidemic process on multiplex networks. •SIR model and bond percolation theory are used to analyze the epidemic processes. •We derive equations to accurately calculate the epidemic threshold and outbreak size. •ASN has no effect on the epidemic threshold and outbreak size. •Strong positive DDC leads to a lower epidemic threshold and a smaller outbreak size.
Full Text Available The contact structure between hosts shapes disease spread. Most network-based models used in epidemiology tend to ignore heterogeneity in the weighting of contacts between two individuals. However, this assumption is known to be at odds with the data for many networks (e.g. sexual contact networks and to have a critical influence on epidemics' behavior. One of the reasons why models usually ignore heterogeneity in transmission is that we currently lack tools to analyze weighted networks, such that most studies rely on numerical simulations. Here, we present a novel framework to estimate key epidemiological variables, such as the rate of early epidemic expansion (r0 and the basic reproductive ratio (R0, from joint probability distributions of number of partners (contacts and number of interaction events through which contacts are weighted. These distributions are much easier to infer than the exact shape of the network, which makes the approach widely applicable. The framework also allows for a derivation of the full time course of epidemic prevalence and contact behaviour, which we validate with numerical simulations on networks. Overall, incorporating more realistic contact networks into epidemiological models can improve our understanding of the emergence and spread of infectious diseases.
Barrais, Robert; Faucher, Benoît; Haus, Rachel; Piarroux, Martine; Gaudart, Jean; Magloire, Roc; Raoult, Didier
After onset of a cholera epidemic in Haiti in mid-October 2010, a team of researchers from France and Haiti implemented field investigations and built a database of daily cases to facilitate identification of communes most affected. Several models were used to identify spatiotemporal clusters, assess relative risk associated with the epidemic’s spread, and investigate causes of its rapid expansion in Artibonite Department. Spatiotemporal analyses highlighted 5 significant clusters (p<0.001): 1 near Mirebalais (October 16–19) next to a United Nations camp with deficient sanitation, 1 along the Artibonite River (October 20–28), and 3 caused by the centrifugal epidemic spread during November. The regression model indicated that cholera more severely affected communes in the coastal plain (risk ratio 4.91) along the Artibonite River downstream of Mirebalais (risk ratio 4.60). Our findings strongly suggest that contamination of the Artibonite and 1 of its tributaries downstream from a military camp triggered the epidemic. PMID:21762567
Avalos, Javier; Carmen Limón, M
Carotenoids are terpenoid pigments widespread in nature, produced by bacteria, fungi, algae and plants. They are also found in animals, which usually obtain them through the diet. Carotenoids in plants provide striking yellow, orange or red colors to fruits and flowers, and play important metabolic and physiological functions, especially relevant in photosynthesis. Their functions are less clear in non-photosynthetic microorganisms. Different fungi produce diverse carotenoids, but the mutants unable to produce them do not exhibit phenotypic alterations in the laboratory, apart of lack of pigmentation. This review summarizes the current knowledge on the functional basis for carotenoid production in fungi. Different lines of evidence support a protective role of carotenoids against oxidative stress and exposure to visible light or UV irradiation. In addition, the carotenoids are intermediary products in the biosynthesis of physiologically active apocarotenoids or derived compounds. This is the case of retinal, obtained from the symmetrical oxidative cleavage of β-carotene. Retinal is the light-absorbing prosthetic group of the rhodopsins, membrane-bound photoreceptors present also in many fungal species. In Mucorales, β-carotene is an intermediary in the synthesis of trisporoids, apocarotenoid derivatives that include the sexual hormones the trisporic acids, and they are also presumably used in the synthesis of sporopollenin polymers. In conclusion, fungi have adapted their ability to produce carotenoids for different non-essential functions, related with stress tolerance or with the synthesis of physiologically active by-products.
Rojek, Amanda M; Horby, Peter W
Emerging and epidemic infectious disease outbreaks are a significant public health problem and global health security threat. As an outbreak begins, epidemiological investigations and traditional public health responses are generally mounted very quickly. However, patient-centred research is usually not prioritised when planning and enacting the response. Instead, the clinical research response occurs subsequent to and separate from the public health response, and is inadequate for evidence-based decision-making at the bedside or in the offices of public health policymakers. The deficiencies of the clinical research response to severe acute respiratory syndrome, pandemic influenza, Middle East respiratory syndrome coronavirus and Ebola virus demonstrate that current research models do not adequately inform and improve the quality of clinical care or public health response. Three suggestions for improvements are made. First, integrate the data and sample collection needs for clinical and public health decision-making within a unified framework, combined with a risk-based, rather than a discipline-based, approach to ethical review and consent. Second, develop clinical study methods and tools that are specifically designed to meet the epidemiological and contextual challenges of emerging and epidemic infectious diseases. Third, invest in investigator-led clinical research networks that are primed and incentivised to respond to outbreak infections, and which can call on the support and resources of a central centre of excellence. It is crucial that the field of epidemic science matures to place patients at the heart of the response. This can only be achieved when patient-centred research is integrated in the outbreak response from day one and practical steps are taken to reduce the barriers to the generation of reliable and useful evidence.
Thomas W Crowther
Full Text Available Fungi are prominent components of most terrestrial ecosystems, both in terms of biomass and ecosystem functioning, but the hyper-diverse nature of most communities has obscured the search for unifying principles governing community organization. In particular, unlike plants and animals, observational studies provide little evidence for the existence of niche processes in structuring fungal communities at broad spatial scales. This limits our capacity to predict how communities, and their functioning, vary across landscapes. We outline how a shift in focus, from taxonomy towards functional traits, might prove to be valuable in the search for general patterns in fungal ecology. We build on theoretical advances in plant and animal ecology to provide an empirical framework for a trait-based approach in fungal community ecology. Drawing upon specific characteristics of the fungal system, we highlight the significance of drought stress and combat in structuring free-living fungal communities. We propose a conceptual model to formalize how trade-offs between stress-tolerance and combative dominance are likely to organize communities across environmental gradients. Given that the survival of a fungus in a given environment is contingent on its ability to tolerate antagonistic competitors, measuring variation in combat trait expression along environmental gradients provides a means of elucidating realized, from fundamental niche spaces. We conclude that, using a trait-based understanding of how niche processes structure fungal communities across time and space, we can ultimately link communities with ecosystem functioning. Our trait-based framework highlights fundamental uncertainties that require testing in the fungal system, given their potential to uncover general mechanisms in fungal ecology.
Chitin is a homopolymer of N-acetyl-d-glucosamine (GlcNAc)that is abundantly present in nature and found as a major structural component in the fungal cell wall. In Chapter 1,the role of chitin as an important factor in the interaction between fungal pathogens and their
Constance I. Millar; Bohun B. Kinloch; Robert D. Westfall
Genetic diversity in sugar plne will be severely reduced by the blister rust pandemic predicted within the next 50 to 75 years. We model effects of the epidemic on genetic diversity at the stand and landscape levels for both natural and artificial regeneration. In natural stands, because natural frequencies of the dominant gene (R) for resistance are low, the most...
Brookman, J.L.; Nicholson, M.J.
The development of molecular techniques has greatly broadened our view of microbial diversity and enabled a more complete detection and description of microbial communities. The application of these techniques provides a simple means of following community changes, for example, Ishii et al. described transient and more stable inhabitants in another dynamic microbial system, compost. Our present knowledge of anaerobic gut fungal population diversity within the gastrointestinal tract is based upon isolation, cultivation and observations in vivo. It is likely that there are many species yet to be described, some of which may be non-culturable. We have observed a distinct difference in the ease of cultivation between the different genera, for example, Caecomyes isolates are especially difficult to isolate and maintain in vitro, a feature that is likely to result in the under representation of this genera in culture-based enumerations. The anaerobic gut fungi are the only known obligately anaerobic fungi. For the majority of their life cycles, they are found tightly associated with solid digesta in the rumen and/or hindgut. They produce potent fibrolytic enzymes and grow invasively on and into the plant material they are digesting making them important contributors to fibre digestion. This close association with intestinal digesta has made it difficult to accurately determine the amount of fungal biomass present in the rumen, with Orpin suggesting 8% contribution to the total microbial biomass, whereas Rezaeian et al. more recently gave a value of approximately 20%. It is clear that the rumen microbial complement is affected by dietary changes, and that the fungi are more important in digestion in the rumens of animals fed with high-fibre diets. It seems likely that the gut fungi play an important role within the rumen as primary colonizers of plant fibre, and so we are particularly interested in being able to measure the appearance and diversity of fungi on the plant
Full Text Available Fournier's Gangrene is a rapidly progressive necrotizing fasciitis of the groin, perianal and perineal region that is often polymicrobial in nature, often averaging 3 species of bacteria per patient. The typical infection can be due to a host of microbes, including gram positive, gram negative and anaerobic species including. Many of the causative organisms are found in the normal microbial flora of the perineum. Therefore, Fourniers is an opportunistic infection most commonly affecting the immunosuppressed. The majority of Fournier's gangrene are bacterial; however there have been cases of fungal Fournier's gangrene reported in the literature.
Lu, Tao; Yao, Bo; Zhang, Chi
Fungal pathogens cause various diseases for plant and animal hosts. Despite the extensive impact of fungi on human health and life, the threats posed by emerging fungal pathogens are poorly understood. Specifically, there exist few fungal virulence gene databases, which prevent effective bioinformatics studies on fungal pathogens. Therefore, we constructed a comprehensive online database of known fungal virulence factors, which collected 2058 pathogenic genes produced by 228 fungal strains from 85 genera. This database creates a pivotal platform capable of stimulating and facilitating further bench studies on fungal pathogens. Database URL: http://sysbio.unl.edu/DFVF/ PMID:23092926
... includes places like chicken coops and caves. Wear gloves when handling materials such as soil, moss, or ... MMWR: Recommendations and Reports 2000;49:1-128. Top of Page Related Links Fungal Meningitis National Center ...
Bodó, Ágnes; Katona, Gyula Y; Simon, Péter L
Mathematical modelling of epidemic propagation on networks is extended to hypergraphs in order to account for both the community structure and the nonlinear dependence of the infection pressure on the number of infected neighbours. The exact master equations of the propagation process are derived for an arbitrary hypergraph given by its incidence matrix. Based on these, moment closure approximation and mean-field models are introduced and compared to individual-based stochastic simulations. The simulation algorithm, developed for networks, is extended to hypergraphs. The effects of hypergraph structure and the model parameters are investigated via individual-based simulation results.
Pervasive computing systems are inherently running on unstable networks and devices, subject to constant topology changes, network failures, and high churn. For this reason, pervasive computing infrastructures need to handle these issues as part of their design. This is, however, not feasible...... epidemic protocols as distribution mechanism for pervasive systems. The nature of epidemic protocols make them easy to implement, easy to deploy, and resilient to failures. By using epidemic protocols, it is possible to mitigate a wide range of the potential issues on the protocol layer. The result...... is lower complexity of building pervasive systems and higher robustness....
Chooi, Yit-Heng; Tang, Yi
The iterative type I polyketide synthases (IPKSs) are central to the biosynthesis of an enormously diverse array of natural products in fungi. These natural products, known as polyketides, exhibit a wide range of biological activities and include clinically important drugs as well as undesirable toxins. The PKSs synthesize these structurally diverse polyketides via a series of decarboxylative condensations of malonyl-CoA extender units and β-keto modifications in a highly programmed manner. Significant progress has been made over the past few years in understanding the biosynthetic mechanism and programming of fungal PKSs. The continuously expanding fungal genome sequence data have sparked genome-directed discoveries of new fungal PKSs and associated products. The increasing number of fungal PKSs that have been linked to their products along with in-depth biochemical and structural characterizations of these large enzymes have remarkably improved our knowledge on the molecular basis for polyketide structural diversity in fungi. This Perspective highlights the recent advances and examines how the newly expanded paradigm has contributed to our ability to link fungal PKS genes to chemical structures and vice versa. The knowledge will help us navigate through the logarithmically expanding seas of genomic information for polyketide compound discovery and provided opportunities to reprogram these megasynthases to generate new chemical entities.
Sokol, Harry; Leducq, Valentin; Aschard, Hugues; Pham, Hang-Phuong; Jegou, Sarah; Landman, Cecilia; Cohen, David; Liguori, Giuseppina; Bourrier, Anne; Nion-Larmurier, Isabelle; Cosnes, Jacques; Seksik, Philippe; Langella, Philippe; Skurnik, David; Richard, Mathias L; Beaugerie, Laurent
Objective The bacterial intestinal microbiota plays major roles in human physiology and IBDs. Although some data suggest a role of the fungal microbiota in IBD pathogenesis, the available data are scarce. The aim of our study was to characterise the faecal fungal microbiota in patients with IBD. Design Bacterial and fungal composition of the faecal microbiota of 235 patients with IBD and 38 healthy subjects (HS) was determined using 16S and ITS2 sequencing, respectively. The obtained sequences were analysed using the Qiime pipeline to assess composition and diversity. Bacterial and fungal taxa associated with clinical parameters were identified using multivariate association with linear models. Correlation between bacterial and fungal microbiota was investigated using Spearman's test and distance correlation. Results We observed that fungal microbiota is skewed in IBD, with an increased Basidiomycota/Ascomycota ratio, a decreased proportion of Saccharomyces cerevisiae and an increased proportion of Candida albicans compared with HS. We also identified disease-specific alterations in diversity, indicating that a Crohn's disease-specific gut environment may favour fungi at the expense of bacteria. The concomitant analysis of bacterial and fungal microbiota showed a dense and homogenous correlation network in HS but a dramatically unbalanced network in IBD, suggesting the existence of disease-specific inter-kingdom alterations. Conclusions Besides bacterial dysbiosis, our study identifies a distinct fungal microbiota dysbiosis in IBD characterised by alterations in biodiversity and composition. Moreover, we unravel here disease-specific inter-kingdom network alterations in IBD, suggesting that, beyond bacteria, fungi might also play a role in IBD pathogenesis. PMID:26843508
Thyssen, Jacob Pontoppidan; Johansen, Jeanne Duus; Menné, Torkil
Contact dermatitis can be severe and lead to sick leave as well as significant healthcare expenses. The aim of this review is to present the published knowledge on 6 historical epidemics of contact allergy to apply this knowledge on the prevention and control of future contact allergy epidemics...... to prevent contact allergy epidemics. It is essential that dermatologist, scientists, administrators, and consumers organize and structure known methods to accelerate the control of emerging contact allergens....
Zurita, J; Denning, D W; Paz-Y-Miño, A; Solís, M B; Arias, L M
There is a dearth of data from Ecuador on the burden of life-threatening fungal disease entities; therefore, we estimated the burden of serious fungal infections in Ecuador based on the populations at risk and available epidemiological databases and publications. A full literature search was done to identify all epidemiology papers reporting fungal infection rates. WHO, ONU-AIDS, Index Mundi, Global Asthma Report, Globocan, and national data [Instituto Nacional de Estadística y Censos (INEC), Ministerio de Salud Pública (MSP), Sociedad de Lucha Contra el Cáncer (SOLCA), Instituto Nacional de Donación y Trasplante de Órganos, Tejidos y Células (INDOT)] were reviewed. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology by LIFE. Ecuador has a variety of climates from the cold of the Andes through temperate to humid hot weather at the coast and in the Amazon basin. Ecuador has a population of 15,223,680 people and an average life expectancy of 76 years. The median estimate of the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) population at risk for fungal disease (Ecuador is affected by serious fungal infection.
Full Text Available Of the ceramide monohexosides (CMHs, gluco- and galactosylceramides are the main neutral glycosphingolipids expressed in fungal cells. Their structural determination is greatly dependent on the use of mass spectrometric techniques, including fast atom bombardment-mass spectrometry (FAB-MS, electrospray ionization (ESI-MS, and energy collision-induced dissociation mass spectrometry (ESI-MS/CID-MS. Nuclear magnetic resonance (NMR has also been used successfully. Such a combination of techniques, combined with classical analytical separation, such as HPTLC and column chromatography, has led to the structural elucidation of a great number of fungal CMHs. The structure of fungal CMH is conserved among fungal species and consists of a glucose or galactose residue attached to a ceramide moiety containing 9-methyl-4,8-sphingadienine with an amidic linkage to hydroxylated fatty acids, most commonly having 16 or 18 carbon atoms and unsaturation between C-3 and C-4. Along with their unique structural characteristics, fungal CMHs have a peculiar subcellular distribution and striking biological properties. Fungal cerebrosides were also characterized as antigenic molecules directly or indirectly involved in cell growth or differentiation in Schizophyllum commune, Cryptococcus neoformans, Pseudallescheria boydii, Candida albicans, Aspergillus nidulans, A.fumigatus and Colletotrichum gloeosporioides. Besides classical techniques for cerebroside (CMH analysis, we now describe new approaches, combining conventional TLC and mass spectrometry, as well as emerging technologies for subcellular localization and distribution of glycosphingolipids by SIMS and imaging MALDI TOF .
Manzano, Marc; Calle, Eusebi; Ripoll, Jordi
in telecommunication networks has not been extensively considered, nowadays, with the increasing computation capacity and complexity of operating systems of modern network devices (routers, switches, etc.), the study of possible epidemic-like failure scenarios must be taken into account. When epidemics occur......, such as in other multiple failure scenarios, identifying the level of vulnerability offered by a network is one of the main challenges. In this paper, we present epidemic survivability, a new network measure that describes the vulnerability of each node of a network under a specific epidemic intensity. Moreover......, this metric is able to identify the set of nodes which are more vulnerable under an epidemic attack. In addition, two applications of epidemic survivability are provided. First, we introduce epidemic criticality, a novel robustness metric for epidemic failure scenarios. A case study shows the utility...
Dong, Chao; Yin, Qiuju; Liu, Wenyang; Yan, Zhijun; Shi, Tianyu
Relation existed in the social contact network can affect individuals' behaviors greatly. Considering the diversity of relation intimacy among network nodes, an epidemic propagation model is proposed by incorporating the link-breaking threshold, which is normally neglected in the rewiring strategy. The impact of rewiring strategy on the epidemic spreading in the weighted adaptive network is explored. The results show that the rewiring strategy cannot always control the epidemic prevalence, especially when the link-breaking threshold is low. Meanwhile, as well as strong links, weak links also play a significant role on epidemic spreading.
Bogner, C.W.; Kamdem, R.S.; Stichtermann, G.; Matthäus, C.; Hölscher, D.; Popp, J.; Proksch, P.; Grundler, F.M.; Schouten, A.
In order to replace particularly biohazardous nematocides, there is a strong drive to finding natural product-based alternatives with the aim of containing nematode pests in agriculture. The metabolites produced by the fungal endophyte Fusarium oxysporum 162 when cultivated on rice media were
S. Seyedmousavi (Seyedmojtaba); J. Guillot; A. Tolooe (Ali); P.E. Verweij (Paul); G.S. de Hoog
textabstractZoonotic fungi can be naturally transmitted between animals and humans, and in some cases cause significant public health problems. A number of mycoses associated with zoonotic transmission are among the group of the most common fungal diseases, worldwide. It is, however, notable that
Anyaogu, Diana Chinyere; Mortensen, Uffe Hasbro
Fungal natural products comprise a wide range of compounds. Some are medically attractive as drugs and drug leads, some are used as food additives, while others are harmful mycotoxins. In recent years the genome sequence of several fungi has become available providing genetic information of a lar...
Alvarez Duarte, E; Denning, D W
The incidence and prevalence of fungal infections in Chile are unknown. Here, we have estimated the burden of serious fungal diseases from data obtained from clinical reports, WHO reports, Chilean census, OECD reports and comprehensive literature search available on PubMed and SciELO, among other scientific resources. Due the lack of official data about fungal diseases, frequencies were calculated based on the specific populations at risk. Recurrent vulvovaginal candidiasis (>4 episodes/year) is estimated to occur in 3108/100,000. Using a low international average rate of 5/100,000, we estimate 878 candidaemia cases and 132 patients with intra-abdominal candidiasis. Due to the low incidence of pulmonary tuberculosis (TB) in Chile, limited numbers of patients with chronic pulmonary aspergillosis are likely: a total of 1212, 25% following TB. Invasive aspergillosis is estimated to affect 296 patients following leukaemia therapy, transplantation and chronic obstructive pulmonary disease (COPD), 1.7/100,000. In addition, allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitisation (SAFS) were estimated to be around 97.9/100,000 and 127/100,000 respectively, in 675,772 adult asthmatics and 1700 CF patients. Given a 38,000 human immunodeficiency virus (HIV) population, with around 2189 new cases of acquired immune deficiency syndrome (AIDS) annually, cryptococcal meningitis and Pneumocystis pneumonia are estimated at 0.12/100,000 and 4.3/100,000, respectively. In total, 325,000 (1.9%) people in Chile develop serious fungal infections annually. Respiratory fungal disease predominates in Chile; a national action plan for fungal disease is urgently needed, including epidemiological studies to validate the estimates.
Crawford, Jason M; Townsend, Craig A
Fungal aromatic polyketides constitute a large family of bioactive natural products and are synthesized by the non-reducing group of iterative polyketide synthases (PKSs). Their diverse structures arise from selective enzymatic modifications of reactive, enzyme-bound poly-β-keto intermediates. How iterative PKSs control starter unit selection, polyketide chain initiation and elongation, intermediate folding and cyclization, selective redox or modification reactions during assembly, and product release are central mechanistic questions underlying iterative catalysis. This Review highlights recent insights into these questions, with a particular focus on the biosynthetic programming of fungal aromatic polyketides, and draws comparisons with the allied biosynthetic processes in bacteria.
Roy, Biswajit G
Various viral diseases, such as acquired immunodeficiency syndrome, influenza, and hepatitis, have emerged as leading causes of human death worldwide. Scientific endeavor since invention of DNA-dependent RNA polymerase of pox virus in 1967 resulted in better understanding of virus replication and development of various novel therapeutic strategies. Despite considerable advancement in every facet of drug discovery process, development of commercially viable, safe, and effective drugs for these viruses still remains a big challenge. Decades of intense research yielded a handful of natural and synthetic therapeutic options. But emergence of new viruses and drug-resistant viral strains had made new drug development process a never-ending battle. Small-molecule fungal metabolites due to their vast diversity, stereochemical complexity, and preapproved biocompatibility always remain an attractive source for new drug discovery. Though, exploration of therapeutic importance of fungal metabolites has started early with discovery of penicillin, recent prediction asserted that only a small percentage (5-10%) of fungal species have been identified and much less have been scientifically investigated. Therefore, exploration of new fungal metabolites, their bioassay, and subsequent mechanistic study bears huge importance in new drug discovery endeavors. Though no fungal metabolites so far approved for antiviral treatment, many of these exhibited high potential against various viral diseases. This review comprehensively discussed about antiviral activities of fungal metabolites of diverse origin against some important viral diseases. This also highlighted the mechanistic details of inhibition of viral replication along with structure-activity relationship of some common and important classes of fungal metabolites.
Conclusion: Universal screening for pulmonary fungal infection especially in patients with fungal rhino sinusitis is highly recommended to treat it early, decrease morbidity and mortality of the diseases.
Fungi and fungal enzymes play important roles in the new bioeconomy. Enzymes from filamentous fungi can unlock the potential of recalcitrant lignocellulose structures of plant cell walls as a new resource, and fungi such as yeast can produce bioethanol from the sugars released after enzyme treatment. Such processes reflect inherent characteristics of the fungal way of life, namely, that fungi as heterotrophic organisms must break down complex carbon structures of organic materials to satisfy their need for carbon and nitrogen for growth and reproduction. This chapter describes major steps in the conversion of plant biomass to value-added products. These products provide a basis for substituting fossil-derived fuels, chemicals, and materials, as well as unlocking the biomass potential of the agricultural harvest to yield more food and feed. This article focuses on the mycological basis for the fungal contribution to biorefinery processes, which are instrumental for improved resource efficiency and central to the new bioeconomy. Which types of processes, inherent to fungal physiology and activities in nature, are exploited in the new industrial processes? Which families of the fungal kingdom and which types of fungal habitats and ecological specializations are hot spots for fungal biomass conversion? How can the best fungal enzymes be found and optimized for industrial use? How can they be produced most efficiently-in fungal expression hosts? How have industrial biotechnology and biomass conversion research contributed to mycology and environmental research? Future perspectives and approaches are listed, highlighting the importance of fungi in development of the bioeconomy.
The study concluded that TTO, being a natural product, is a better nontoxic modality compared to clotrimazole, in the treatment of oral fungal infection and has a promising future for its potential application in oral health products.
This paper aims to study corruption as an epidemic phenomenon using the epidemic diffusion model of Kermack and Mc-Kendrick (1927). We seek to determine the dynamics of corruption and its impact on the composition of the population at a given time. We determine a threshold epidemiological corruption based on the approximation of the honest population.
Ruepp, Sarah Renée; Katsikas, Dimitrios; Fagertun, Anna Manolova
This paper presents a failure propagation model for transport networks which are affected by epidemic failures. The network is controlled using the GMPLS protocol suite. The Susceptible Infected Disabled (SID) epidemic model is investigated and new signaling functionality of GMPLS to support...
Mokrani, K; Fournier, P E; Dalichaouche, M; Tebbal, S; Aouati, A; Raoult, D
We report a case of epidemic typhus in a patient from the Batna region of Algeria, who presented with generalized febrile exanthema. The clinical diagnosis was confirmed by serological cross-adsorption followed by Western blotting. Our report emphasizes the threat of epidemic typhus in the highlands of Algeria.
Full Text Available Mathematical analysis and modelling is central to infectious disease epidemiology. This paper, inspired by the natural ripple-spreading phenomenon, proposes a novel ripple-spreading network model for the study of infectious disease transmission. The new epidemic model naturally has good potential for capturing many spatial and temporal features observed in the outbreak of plagues. In particular, using a stochastic ripple-spreading process simulates the effect of random contacts and movements of individuals on the probability of infection well, which is usually a challenging issue in epidemic modeling. Some ripple-spreading related parameters such as threshold and amplifying factor of nodes are ideal to describe the importance of individuals’ physical fitness and immunity. The new model is rich in parameters to incorporate many real factors such as public health service and policies, and it is highly flexible to modifications. A genetic algorithm is used to tune the parameters of the model by referring to historic data of an epidemic. The well-tuned model can then be used for analyzing and forecasting purposes. The effectiveness of the proposed method is illustrated by simulation results.
Hashimoto, Makoto; Nonaka, Takamasa; Fujii, Isao
This article covers the literature on fungal type III polyketide synthases (PKSs) published from 2005 to 2014. Since the first discovery of fungal type III PKS genes in Aspergillus oryzae, reported in 2005, putative genes for type III PKSs have been discovered in fungal genomes. Compared with type I PKSs, type III PKSs are much less abundant in fungi. However, type III PKSs could have some critical roles in fungi. This article summarizes the studies on fungal type III PKS functional analysis, including Neurospora crassa ORAS, Aspergillus niger AnPKS, Botrytis cinerea BPKS and Aspergillus oryzae CsyA and CsyB. It is mostly in vitro analysis using their recombinant enzymes that has revealed their starter and product specificities. Of these, CsyB was found to be a new kind of type III PKS that catalyses the coupling of two β-keto fatty acyl CoAs. Homology modelling reported in this article supports the importance of the capacity of the acyl binding tunnel and active site cavity in fungal type III PKSs.
Full Text Available Laboratory tests for the detection of fungal infections are easy to perform. The main obstacle to a correct diagnosis is the correlation between the laboratory findings and the clinical diagnosis. Among pediatric patients, the most common fungal pathogen is Candida. The detection of fungal colonization may be performed through the use of chromogenic culture media, which allows also the identification of Candida subspecies, from which pathogenicity depends. In neonatology, thistest often drives the decision to begin a empiric therapy; in this regard, a close cooperation between microbiologists and clinicians is highly recommended. Blood culture, if positive, is a strong confirmation of fungal infection; however, its low sensitivity results in a high percentage of false negatives, thus decreasing its reliability. Molecular diagnostics is still under evaluation, whereas the detection of some fungal antigens, such as β-D-glucan, galactomannan, mannoprotein, and cryptococcal antigen in the serum is used for adults, but still under evaluations for pediatric patients.http://dx.doi.org/10.7175/rhc.v4i1S.862
Visscher, T L S; Heitmann, B L; Rissanen, A
epidemic. However, follow-ups of short duration may, in part, explain the apparent break or decrease in the obesity epidemic. On the other hand, a single focus on body mass index (BMI) ⩾25 or ⩾30 kg m(-)(2) is likely to mask a real increase in the obesity epidemic. And, in both children and adults, trends......Recent epidemiologic papers are presenting prevalence data suggesting breaks and decreases in obesity rates. However, before concluding that the obesity epidemic is not increasing anymore, the validity of the presented data should be discussed more thoroughly. We had a closer look...... into the literature presented in recent reviews to address the major potential biases and distortions, and to develop insights about how to interpret the presented suggestions for a potential break in the obesity epidemic. Decreasing participation rates, the use of reported rather than measured data and small sample...
Smilović, V; Vrbanec-Megla, L; Payerl-Pal, M; Puntarić, D; Baklaić, Z
Two closely related boys from the same house hold (Home 1), aged two and three, were affected with fulminant meningococcal sepsis known as Waterhouse-Friderichsen syndrome. Neisseria meningitidis serogorup B was isolated from their blood and cerebrospinal fluid. The two-year-old boy died one day after the onset of the disease. Epidemiological examination of contacts and pharyngeal swabs were performed in 14 persons from the household, all of them relatives of the affected children, as well as in a number of other contacts. Chemoprophylaxis with cotrimoxazole was simultaneously administered to all contacts. Family histories revealed that two contacts from the household where the patients did not live (Home 2) were inadvertently omitted. Subsequent examinations, following a report of another contagious disease (salmonelosis), revealed that these two persons were Neisseria meningitidis carriers, together with another one in the same household. The carriers most probably caused the infection of a third, five-year-old boy, the deceased boy's brother (Home 1) who also developed fulminant meningococcal sepsis. The failure to take the appropriate prophylaxis led to a prolonged carrier state in the carrier from the second household. Repeated pharyngeal swab sampling revealed two more carriers from both households that had previously been negative. Control of the epidemic was achieved after 5 weeks by repeated and controlled chemoprophylaxis with ciprofloxacin, and by repeated epidemiological examinations, disinfection, and daily health surveillance by the Sanitary Inspectorate. This extremely rare instance of a familial epidemic with three infected persons emphasizes the need for consistent chemoprophylaxis in meningococcal disease contacts.
Vega, Tomás; Lozano, Jose Eugenio; Meerhoff, Tamara; Snacken, René; Mott, Joshua; Ortiz de Lejarazu, Raul; Nunes, Baltazar
Please cite this paper as: Vega et al. (2012) Influenza surveillance in Europe: establishing epidemic thresholds by the moving epidemic method. Influenza and Other Respiratory Viruses 7(4), 546–558. Background Timely influenza surveillance is important to monitor influenza epidemics. Objectives (i) To calculate the epidemic threshold for influenza‐like illness (ILI) and acute respiratory infections (ARI) in 19 countries, as well as the thresholds for different levels of intensity. (ii) To evaluate the performance of these thresholds. Methods The moving epidemic method (MEM) has been developed to determine the baseline influenza activity and an epidemic threshold. False alerts, detection lags and timeliness of the detection of epidemics were calculated. The performance was evaluated using a cross‐validation procedure. Results The overall sensitivity of the MEM threshold was 71·8% and the specificity was 95·5%. The median of the timeliness was 1 week (range: 0–4·5). Conclusions The method produced a robust and specific signal to detect influenza epidemics. The good balance between the sensitivity and specificity of the epidemic threshold to detect seasonal epidemics and avoid false alerts has advantages for public health purposes. This method may serve as standard to define the start of the annual influenza epidemic in countries in Europe. PMID:22897919
Monnanda Somaiah Nalini
Full Text Available Endophytes constitute an important component of microbial diversity, and in the present investigation, seven plant species with rich ethnobotanical uses representing six families were analyzed for the presence of endophytic fungi from their natural habitats during monsoon (May/June and winter (November/December seasons of 2007. Fungal endophytes were isolated from healthy plant parts such as stem, root, rhizome, and inflorescence employing standard isolation methods. One thousand five hundred and twenty-nine fungal isolates were obtained from 5200 fragments. Stem fragments harbored more endophytes (80.37% than roots (19.22%. 31 fungal taxa comprised of coelomycetes (65%, hyphomycetes (32%, and ascomycetes (3%. Fusarium, Acremonium, Colletotrichum, Chaetomium, Myrothecium, Phomopsis, and Pestalotiopsis spp. were commonly isolated. Diversity indices differed significantly between the seasons (P<0.001. Species richness was greater for monsoon isolations than winter. Host specificity was observed for few fungal endophytes. UPGMA cluster analysis grouped the endophytes into distinct clusters on the basis of genetic distance. This study is the first report on the diversity and host-specificity of endophytic fungal taxa were from the semi evergreen forest type in Talacauvery subcluster of Western Ghats.
Zafar Iqbal*, Uzma Sheikh and Rabia Mughal
Full Text Available Aim of this study was to investigate fungal infections in four species of carps including goldfish, Carassius (C. auratus L.; silver carp, Hypophthalmichthys (H. molitrix Richardsons; rahu, Labeo (L. rohita Hamilton and Ctenopharyngodon (C. idella Valenciennes. Nine specimens of each species were studied for the presence of fungal infections. Infected fishes showed clinical signs such as fungal growth on skin, fins, eyes, eroded fins and scales, hemorrhages on body surface and abdominal distension. The specimens from infected organs of fish were inoculated on each, malt extract, Sabouraud dextrose and potato dextrose agars. The fungal colonies of white, black, green, grey and brown colors were observed in the agar plates. Slides were prepared and stained with 0.05% Trypan blue in lactophenol. C. auratus showed the highest infection rate (44.4% followed by H. molitrix and L. rohita (11.1% each. Five fungal species viz. Aspergillus (33.3%, Penicillium (22.2%, Alternaria (27.7%, Blastomyces spp (11.1% and Rhizopus (5.5% were isolated. Posterior part of the fish had significantly (P=0.05 higher (62.5% infection as compared to anterior part (37.5%. The caudal fin with 31.25% infection was the single most affected area. This study showed that most of the fungi isolated from fishes are considered as normal mycoflora, yet many fungi can cause natural infections in ponds and aquarium.
Full Text Available Previous studies have revealed inconsistent correlations between fungal diversity and plant/soil properties from local to global scales. Here, we investigated the internal relationships between soil fungal diversity and plant/soil properties on the Loess Plateau following vegetation restoration, using Illumina sequencing of the internal transcribed spacer 2 (ITS2 region for fungal identification. We found significant effects of land use types (Af, Artificial forest; Ns, Natural shrub; Ag, Artificial grassland; Ng, Natural grassland; Sc, slope cropland on soil fungal communities composition, and the dominant phyla were Ascomycota, Basidiomycota, and Zygomycota, which transitioned from Basidiomycota-dominant to Ascomycota-dominant community due to vegetation restoration. The Chao1 richness, Shannon’s diversity and ACE indices were significantly influenced by land use types with the order of Ns > Af > Ng > Ag > Sc, and the total number of OTUs varied widely. In contrast, Good’s coverage and Simpson’s diversity indicated no significant difference among land use types (p > 0.05. Correlation analysis showed that plant and soil properties were closely related to fungal diversity regardless of land use types. In addition, soil organic carbon (SOC and Hplant (plant richness, Shannon-Wiener index were strong driving factors that explained fungal diversity. As revealed by the structural equation model (SEM and generalized additive models (GAMs, fungal diversity was directly and indirectly affected by soil and plant properties, respectively, providing evidence for strong links between soil fungal diversity and plant and soil properties on the Loess Plateau.
Gazol, Antonio; Zobel, Martin; Cantero, Juan José; Davison, John; Esler, Karen J; Jairus, Teele; Öpik, Maarja; Vasar, Martti; Moora, Mari
The introduction of alien plants can influence biodiversity and ecosystems. However, its consequences for soil microbial communities remain poorly understood. We addressed the impact of alien ectomycorrhizal (EcM) pines on local arbuscular mycorrhizal (AM) fungal communities in two regions with contrasting biogeographic histories: in South Africa, where no native EcM plant species are present; and in Argentina, where EcM trees occur naturally. The effect of alien pines on AM fungal communities differed between these regions. In South Africa, plantations of alien EcM pines exhibited lower AM fungal richness and significantly altered community composition, compared with native fynbos. In Argentina, the richness and composition of local AM fungal communities were similar in plantations of alien EcM pines and native forest. However, the presence of alien pines resulted in slight changes to the phylogenetic structure of root AM fungal communities in both regions. In pine clearcut areas in South Africa, the richness and composition of AM fungal communities were intermediate between the native fynbos and the alien pine plantation, which is consistent with natural regeneration of former AM fungal communities following pine removal. We conclude that the response of local AM fungal communities to alien EcM pines differs between biogeographic regions with different histories of species coexistence. © FEMS 2016. All rights reserved. For permissions, please e-mail: email@example.com.
Full Text Available Fungi are an emerging source of peptide antibiotics. With the availability of a large number of model fungal genome sequences, we can expect that more and more fungal defensin-like peptides (fDLPs will be discovered by sequence similarity search. Here, we report a total of 69 new fDLPs encoded by 63 genes, in which a group of fDLPs derived from dermatophytes are defined as a new family (fDEF8 according to sequence and phylogenetic analyses. In the oleaginous fungus Mortierella alpine, fDLPs have undergone extensive gene expansion. Our work further enlarges the fungal defensin family and will help characterize new peptide antibiotics with therapeutic potential.
Powers-Fletcher, Margaret V; Hanson, Kimberly E
Fungal diagnostics that utilize antibody, antigen or nucleic acid detection offer several advantages that supplement traditional culture-based methods. As a group, nonculture assays can help identify patients with invasive fungal infection (IFI) sooner than is possible with culture, are often more sensitive, and can be used to guide early interventions. Challenges associated with these techniques include the possibility for contamination or cross-reactivity as well as the potential for false negative tests. This review summarized the test characteristics and clinical utility of nonculture-based laboratory methods. Copyright © 2016 Elsevier Inc. All rights reserved.
Hofmann, Gerald; Mcintyre, Mhairi; Nielsen, Jens
Fungi are used extensively in both fundamental research and industrial applications. Saccharomyces cerevisiae has been the model organism for fungal research for many years, particularly in functional genomics. However, considering the diversity within the fungal kingdom, it is obvious...... that the application of the existing methods of genome, transcriptome, proteome and metabolome analysis to other fungi has enormous potential, especially for the production of food and food ingredients. The developments in the past year demonstrate that we have only just started to exploit this potential....
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Kharroubi, Akram T; Darwish, Hisham M
The epidemic nature of diabetes mellitus in different regions is reviewed. The Middle East and North Africa region has the highest prevalence of diabetes in adults (10.9%) whereas, the Western Pacific region has the highest number of adults diagnosed with diabetes and has countries with the highest prevalence of diabetes (37.5%). Different classes of diabetes mellitus, type 1, type 2, gestational diabetes and other types of diabetes mellitus are compared in terms of diagnostic criteria, etiology and genetics. The molecular genetics of diabetes received extensive attention in recent years by many prominent investigators and research groups in the biomedical field. A large array of mutations and single nucleotide polymorphisms in genes that play a role in the various steps and pathways involved in glucose metabolism and the development, control and function of pancreatic cells at various levels are reviewed. The major advances in the molecular understanding of diabetes in relation to the different types of diabetes in comparison to the previous understanding in this field are briefly reviewed here. Despite the accumulation of extensive data at the molecular and cellular levels, the mechanism of diabetes development and complications are still not fully understood. Definitely, more extensive research is needed in this field that will eventually reflect on the ultimate objective to improve diagnoses, therapy and minimize the chance of chronic complications development. PMID:26131326
Moro, Armando; Librán, Celia M; Berruga, M Isabel; Zalacain, Amaya; Carmona, Manuel
The use of aromatic plants and their extracts with antimicrobial properties may be compromised in the case of cheese, as some type of fungal starter is needed during its production. Penicillium verrucosum is considered a common cheese spoiler. The aim of this study was to evaluate the innovative use of certain aromatic plants as natural cheese covers in order to prevent mycotoxicogenic fungal growth (P. verrucosum). A collection of 12 essential oils (EOs) was obtained from various aromatic plants by solvent-free microwave extraction technology, and volatile characterisation of the EOs was carried out by gas chromatography/mass spectrometry. The most effective EOs against P. verrucosum were obtained from Anethum graveolens, Hyssopus officinalis and Chamaemelum nobile, yielding 50% inhibition of fungal growth at concentration values lower than 0.02 µL mL⁻¹. All EOs showed high volatile heterogeneity, with α-phellandrene, pinocamphone, isopinocamphone, α-pinene, camphene, 1,8-cineole, carvacrol and trans-anethole being found to be statistically significant in the antifungal model. The use of these aromatic plants as natural covers on cheese can satisfactorily inhibit the growth of some mycotoxicogenic fungal spoilers. Among the volatile compounds present, α- and β-phellandrene were confirmed as the most relevant in the inhibition. © 2012 Society of Chemical Industry.
Full Text Available The increased incidence of systemic fungal infections in the past two decades has been overwhelming. Earlier, it was pathogenic dimorphic fungi, which were known to cause systemic infections. However, starting from the 1960s, opportunistic fungi started causing more number of infections, especially in the immunocompromised host. More recently, newer and less common fungal agents are being increasingly associated with infection in immunosuppressed hosts. Amongst dimorphic fungi, infections due to Histoplasma capsulatum and Penicillium marneffei are increasingly reported in patients with AIDS in India. H. capsulatum is found country wide, but P. marneffei remains restricted to Manipur state. Although both varieties of C. neoformans , C. neoformans var. neoformans (serotypes A & D, and C. neoformans var. gattii (serotypes B & C are reported in India, most of the cases reported are of serotype A. Increased incidence of cryptococcosis is reported from all centers with the emergence of AIDS. Systemic infection due to species under Candida , Aspergillus and zygomycetes is widely prevalent in nosocomial setting, and outbreaks due to unusual fungi are reported occasionally from tertiary care centers. This global change in systemic fungal infections has emphasized the need to develop good diagnostic mycology laboratories in this country and to recognize this increasingly large group of potential fungal pathogens.
Brown, G.D.; Denning, D.W.; Gow, N.A.; Levitz, S.M.; Netea, M.G.; White, T.C.
Although fungal infections contribute substantially to human morbidity and mortality, the impact of these diseases on human health is not widely appreciated. Moreover, despite the urgent need for efficient diagnostic tests and safe and effective new drugs and vaccines, research into the
Bamisope S. Bamisile
Full Text Available The incorporation of entomopathogenic fungi as biocontrol agents into Integrated Pest Management (IPM programs without doubt, has been highly effective. The ability of these fungal pathogens such as Beauveria bassiana and Metarhizium anisopliae to exist as endophytes in plants and protect their colonized host plants against the primary herbivore pests has widely been reported. Aside this sole role of pest management that has been traditionally ascribed to fungal endophytes, recent findings provided evidence of other possible functions as plant yield promoter, soil nutrient distributor, abiotic stress and drought tolerance enhancer in plants. However, reports on these additional important effects of fungal endophytes on the colonized plants remain scanty. In this review, we discussed the various beneficial effects of endophytic fungi on the host plants and their primary herbivore pests; as well as some negative effects that are relatively unknown. We also highlighted the prospects of our findings in further increasing the acceptance of fungal endophytes as an integral part of pest management programs for optimized crop production.
Bamisile, Bamisope S.; Dash, Chandra K.; Akutse, Komivi S.; Keppanan, Ravindran; Wang, Liande
The incorporation of entomopathogenic fungi as biocontrol agents into Integrated Pest Management (IPM) programs without doubt, has been highly effective. The ability of these fungal pathogens such as Beauveria bassiana and Metarhizium anisopliae to exist as endophytes in plants and protect their colonized host plants against the primary herbivore pests has widely been reported. Aside this sole role of pest management that has been traditionally ascribed to fungal endophytes, recent findings provided evidence of other possible functions as plant yield promoter, soil nutrient distributor, abiotic stress and drought tolerance enhancer in plants. However, reports on these additional important effects of fungal endophytes on the colonized plants remain scanty. In this review, we discussed the various beneficial effects of endophytic fungi on the host plants and their primary herbivore pests; as well as some negative effects that are relatively unknown. We also highlighted the prospects of our findings in further increasing the acceptance of fungal endophytes as an integral part of pest management programs for optimized crop production.
Ankrah, Alfred O.; Sathekge, Mike M; Dierckx, Rudi A.J.O.; Glaudemans, Andor W.J.M.
Fungal infections in children rarely occur, but continue to have a high morbidity and mortality despite the development of newer antifungal agents. It is essential for these infections to be diagnosed at the earliest possible stage so appropriate treatment can be initiated promptly. The addition of
Maragkoudakis, Emmanouil; Realdi, Giuseppe; Dore, Maria Pina
In immunocompetent subjects fungal infections of the gastrointestinal tract are uncommon. Candida esophagitis remains the single most common fungal infection in immunocompromised hosts or in H. pylori- infected patients who receive antibiotic therapy. Enteric fungal infections are uncommon even in HIV-infected patients. Antifungal agents such as amphotericin B, ketoconazole, fluconazole, and the various formulations of itraconazole are effective for most cases.
Peng, Xiao-Long; Xu, Xin-Jian; Fu, Xinchu; Small, Michael
Most previous studies of epidemic dynamics on complex networks suppose that the disease will eventually stabilize at either a disease-free state or an endemic one. In reality, however, some epidemics always exhibit sporadic and recurrent behaviour in one region because of the invasion from an endemic population elsewhere. In this paper we address this issue and study a susceptible–infected–susceptible epidemiological model on a network consisting of two communities, where the disease is endemic in one community but alternates between outbreaks and extinctions in the other. We provide a detailed characterization of the temporal dynamics of epidemic patterns in the latter community. In particular, we investigate the time duration of both outbreak and extinction, and the time interval between two consecutive inter-community infections, as well as their frequency distributions. Based on the mean-field theory, we theoretically analyse these three timescales and their dependence on the average node degree of each community, the transmission parameters and the number of inter-community links, which are in good agreement with simulations, except when the probability of overlaps between successive outbreaks is too large. These findings aid us in better understanding the bursty nature of disease spreading in a local community, and thereby suggesting effective time-dependent control strategies. (paper)
Han, Xiao-Pu; Zhao, Zhi-Dan; Hadzibeganovic, Tarik; Wang, Bing-Hong
Hierarchical geographical traffic networks are critical for our understanding of scaling laws in human trajectories. Here, we investigate the susceptible-infected epidemic process evolving on hierarchical networks in which agents randomly walk along the edges and establish contacts in network nodes. We employ a metapopulation modeling framework that allows us to explore the contagion spread patterns in relation to multi-scale mobility behaviors. A series of computer simulations revealed that a shifted power-law-like negative relationship between the peak timing of epidemics τ0 and population density, and a logarithmic positive relationship between τ0 and the network size, can both be explained by the gradual enlargement of fluctuations in the spreading process. We employ a semi-analytical method to better understand the nature of these relationships and the role of pertinent demographic factors. Additionally, we provide a quantitative discussion of the efficiency of a border screening procedure in delaying epidemic outbreaks on hierarchical networks, yielding a rather limited feasibility of this mitigation strategy but also its non-trivial dependence on population density, infector detectability, and the diversity of the susceptible region. Our results suggest that the interplay between the human spatial dynamics, network topology, and demographic factors can have important consequences for the global spreading and control of infectious diseases. These findings provide novel insights into the combined effects of human mobility and the organization of geographical networks on spreading processes, with important implications for both epidemiological research and health policy.
Full Text Available The oceanic crust is believed to host the largest potential habitat for microbial life on Earth, yet, still we lack substantial information about the abundance, diversity, and consequence of its biosphere. The last two decades have involved major research accomplishments within this field and a change in view of the ocean crust and its potential to harbour life. Here fossilised fungal colonies in subseafloor basalts are reported from three different seamounts in the Pacific Ocean. The fungal colonies consist of various characteristic structures interpreted as fungal hyphae, fruit bodies and spores. The fungal hyphae are well preserved with morphological characteristics such as hyphal walls, septa, thallic conidiogenesis, and hyphal tips with hyphal vesicles within. The fruit bodies consist of large (∼50–200 µm in diameter body-like structures with a defined outer membrane and an interior filled with calcite. The fruit bodies have at some stage been emptied of their contents of spores and filled by carbonate-forming fluids. A few fruit bodies not filled by calcite and with spores still within support this interpretation. Spore-like structures (ranging from a few µm to ∼20 µm in diameter are also observed outside of the fruit bodies and in some cases concentrated to openings in the membrane of the fruit bodies. The hyphae, fruit bodies and spores are all closely associated with a crust lining the vein walls that probably represent a mineralized biofilm. The results support a fungal presence in deep subseafloor basalts and indicate that such habitats were vital between ∼81 and 48 Ma.
Full Text Available Culturing of microbes for food production, called cultivation mutualism, has been well-documented from eusocial and subsocial insects such as ants, termites and ambrosia beetles, but poorly described from solitary, non-social insects. Here we report a fungal farming in a non-social lizard beetle Doubledaya bucculenta (Coleoptera: Erotylidae: Languriinae, which entails development of a special female structure for fungal storage/inoculation, so-called mycangium, and also obligate dependence of the insect on the fungal associate. Adult females of D. bucculenta bore a hole on a recently-dead bamboo culm with their specialized mandibles, lay an egg into the internode cavity, and plug the hole with bamboo fibres. We found that the inner wall of the bamboo internode harboring a larva is always covered with a white fungal layer. A specific Saccharomycetes yeast, Wickerhamomyces anomalus ( = Pichia anomala, was consistently isolated from the inner wall of the bamboo internodes and also from the body surface of the larvae. Histological examination of the ovipositor of adult females revealed an exoskeletal pocket on the eighth abdominal segment. The putative mycangium contained yeast cells, and W. anomalus was repeatedly detected from the symbiotic organ. When first instar larvae were placed on culture media inoculated with W. anomalus, they grew and developed normally to adulthood. By contrast, first instar larvae placed on either sterile culture media or autoclaved strips of bamboo inner wall exhibited arrested growth at the second instar, and addition of W. anomalus to the media resumed growth and development of the larvae. These results strongly suggest a mutualistic nature of the D. bucculenta-W. anomalus association with morphological specialization and physiological dependence. Based on these results, we compare the fungal farming of D. bucculenta with those of social and subsocial insects, and discuss ecological factors relevant to the
Zhang, Zhaoyang; Wang, Honggang; Wang, Chonggang; Fang, Hua
Social contact networks and the way people interact with each other are the key factors that impact on epidemics spreading. However, it is challenging to model the behavior of epidemics based on social contact networks due to their high dynamics. Traditional models such as susceptible-infected-recovered (SIR) model ignore the crowding or protection effect and thus has some unrealistic assumption. In this paper, we consider the crowding or protection effect and develop a novel model called improved SIR model. Then, we use both deterministic and stochastic models to characterize the dynamics of epidemics on social contact networks. The results from both simulations and real data set conclude that the epidemics are more likely to outbreak on social contact networks with higher average degree. We also present some potential immunization strategies, such as random set immunization, dominating set immunization, and high degree set immunization to further prove the conclusion.
Seeberg, Jens; Meinert, Lotte
This article argues that the concept of communicability that is central to the distinction between communicable diseases (CDs) and noncommunicable diseases (NCDs) is poorly conceptualized. The epidemic spread of NCDs such as diabetes, depression, and eating disorders demonstrates...
Eng, Thomas R; Butler, William T
.... In addition, STDs increase the risk of HIV transmission. The Hidden Epidemic examines the scope of sexually transmitted infections in the United States and provides a critical assessment of the nation's response to this public health crisis...
Sun, Ye [Institute of Information Economy, Hangzhou Normal University, Hangzhou 311121 (China); Alibaba Research Center of Complexity Science, Hangzhou Normal University, Hangzhou 311121 (China); Liu, Chuang, E-mail: firstname.lastname@example.org [Institute of Information Economy, Hangzhou Normal University, Hangzhou 311121 (China); Alibaba Research Center of Complexity Science, Hangzhou Normal University, Hangzhou 311121 (China); Zhang, Chu-Xu [Institute of Information Economy, Hangzhou Normal University, Hangzhou 311121 (China); Alibaba Research Center of Complexity Science, Hangzhou Normal University, Hangzhou 311121 (China); Zhang, Zi-Ke, E-mail: email@example.com [Institute of Information Economy, Hangzhou Normal University, Hangzhou 311121 (China); Alibaba Research Center of Complexity Science, Hangzhou Normal University, Hangzhou 311121 (China)
Nowadays, the emergence of online services provides various multi-relation information to support the comprehensive understanding of the epidemic spreading process. In this Letter, we consider the edge weights to represent such multi-role relations. In addition, we perform detailed analysis of two representative metrics, outbreak threshold and epidemic prevalence, on SIS and SIR models. Both theoretical and simulation results find good agreements with each other. Furthermore, experiments show that, on fully mixed networks, the weight distribution on edges would not affect the epidemic results once the average weight of whole network is fixed. This work may shed some light on the in-depth understanding of epidemic spreading on multi-relation and weighted networks.
Sun, Ye; Liu, Chuang; Zhang, Chu-Xu; Zhang, Zi-Ke
Nowadays, the emergence of online services provides various multi-relation information to support the comprehensive understanding of the epidemic spreading process. In this Letter, we consider the edge weights to represent such multi-role relations. In addition, we perform detailed analysis of two representative metrics, outbreak threshold and epidemic prevalence, on SIS and SIR models. Both theoretical and simulation results find good agreements with each other. Furthermore, experiments show that, on fully mixed networks, the weight distribution on edges would not affect the epidemic results once the average weight of whole network is fixed. This work may shed some light on the in-depth understanding of epidemic spreading on multi-relation and weighted networks.
Syam Manohar Gadhamsetty
Full Text Available BACKGROUND Chronic sinusitis is one of the common diagnosis in ENT practice. Allergic fungal sinusitis is a clinical entity with characteristic clinical, radiographic and histopathological findings. Allergic fungal sinusitis and eosinophilic mucin rhinosinusitis can easily be misdiagnosed. AIM OF STUDY A prospective clinical study of allergic Fungal Rhinosinusitis to use diagnostic criteria to confirm the disease with Radiological, Pathological & Microbiological investigations and their management. MATERIALS & METHODS A prospective study of allergic Fungal Rhinosinusitis in 2 years from November 2011 to October 2013. Among the patients who attended the ENT OPD during this period, 21 patients with symptoms and signs suggestive of Allergic Fungal Rhinosinusitis are selected.
Information propagation through peer-to-peer systems, online social systems, wireless mobile ad hoc networks and other modern structures can be modelled as an epidemic on a network of contacts. Understanding how epidemic processes interact with network topology allows us to predict ultimate course, understand phase transitions and develop strategies to control and optimise dissemination. This book is a concise introduction for applied mathematicians and computer scientists to basic models, analytical tools and mathematical and algorithmic results. Mathematical tools introduced include coupling
Ellner, S.; Gallant, A.R. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Statistics; Theiler, J. [Santa Fe Inst., NM (United States)]|[Los Alamos National Lab., NM (United States)
Historical data on recurrent epidemics have been central to the debate about the prevalence of chaos in biological population dynamics. Schaffer and Kot who first recognized that the abundance and accuracy of disease incidence data opened the door to applying a range of methods for detecting chaos that had been devised in the early 1980`s. Using attractor reconstruction, estimates of dynamical invariants, and comparisons between data and simulation of SEIR models, the ``case for chaos in childhood epidemics`` was made through a series of influential papers beginning in the mid 1980`s. The proposition that the precise timing and magnitude of epidemic outbreaks are deterministic but chaotic is appealing, since it raises the hope of finding determinism and simplicity beneath the apparently stochastic and complicated surface of the data. The initial enthusiasm for methods of detecting chaos in data has been followed by critical re-evaluations of their limitations. Early hopes of a ``one size fits all`` algorithm to diagnose chaos vs. noise in any data set have given way to a recognition that a variety of methods must be used, and interpretation of results must take into account the limitations of each method and the imperfections of the data. Our goals here are to outline some newer methods for detecting nonlinearity and chaos that have a solid statistical basis and are suited to epidemic data, and to begin a re-evaluation of the claims for nonlinear dynamics and chaos in epidemics using these newer methods. We also identify features of epidemic data that create problems for the older, better known methods of detecting chaos. When we ask ``are epidemics nonlinear?``, we are not questioning the existence of global nonlinearities in epidemic dynamics, such as nonlinear transmission rates. Our question is whether the data`s deviations from an annual cyclic trend (which would reflect global nonlinearities) are described by a linear, noise-driven stochastic process.
Verma, Ravi Kumar; Prabh, Neel Duti; Sankararamakrishnan, Ramasubbu
-like fungal MIPs and the δ AQGPs are unique, hydrophobic in nature and are likely to transport novel hydrophobic solutes. They can be attractive targets for developing anti-fungal drugs. The evolutionary pattern shared with their plant counterparts indicates possible involvement of new fungal MIPs in plant-fungi symbiosis and host-pathogen interactions.
Rodriguez, R.J.; White, J.F.; Arnold, A.E.; Redman, R.S.
All plants in natural ecosystems appear to be symbiotic with fungal endophytes. This highly diverse group of fungi can have profound impacts on plant communities through increasing fitness by conferring abiotic and biotic stress tolerance, increasing biomass and decreasing water consumption, or decreasing fitness by altering resource allocation. Despite more than 100 yr of research resulting in thousands of journal articles, the ecological significance of these fungi remains poorly characterized. Historically, two endophytic groups (clavicipitaceous (C) and nonclavicipitaceous (NC)) have been discriminated based on phylogeny and life history traits. Here, we show that NC-endophytes represent three distinct functional groups based on host colonization and transmission, in planta biodiversity and fitness benefits conferred to hosts. Using this framework, we contrast the life histories, interactions with hosts and potential roles in plant ecophysiology of C- and NC-endophytes, and highlight several key questions for future work in endophyte biology.
Vurro, Maurizio; Boari, Angela; Casella, Francesca; Zonno, Maria Chiara
Fungal phytotoxins are natural secondary metabolites produced by plant pathogenic fungi during host-pathogen interactions. They have received considerable particular attention for elucidating disease etiology, and consequently to design strategies for disease control. Due to wide differences in their chemical structures, these toxic metabolites have different ecological and environmental roles and mechanisms of action. This review aims at summarizing the studies on the possible use of these metabolites as tools in biological and integrated weed management, e.g. as: novel and environmentally friendly herbicides; lead for novel compounds; sources of novel mechanisms of action. Moreover, the limiting factors for utilizing those metabolites in practice will also be briefly discussed. Copyright© Bentham Science Publishers; For any queries, please email at firstname.lastname@example.org.
Egerton-Warburton, L. M.; Schreiner, K. M.; Morgan, B. S. T.; Schultz, J.; Blair, N. E.
Fungi comprise a significant portion of total soil biomass, the turnover of which must represent a dominant flux within the soil carbon cycle. Fungal organic carbon (OC) can turn over on time scales of days to months, but this process is poorly understood. Here, we examined temporal changes in the chemical and microbial community composition of fungal necromass during a 2-month decomposition experiment in which Fusarium avenaceum (a common saprophyte) was exposed to a natural soil microbial community. Over the course of the experiment, residual fungal necromass was harvested and analyzed using FTIR and thermochemolysis-GCMS to examine chemical changes in the tissue. In addition, genomic DNA was extracted from tissues, amplified with barcoded ITS primers, and sequenced using the high-throughput Illumina platform to examine changes in microbial community composition. Up to 80% of the fungal necromass turned over in the first week. This rapid degradation phase corresponded to colonization of the necromass by known chitinolytic soil fungi including Mortierella species. Members of the Zygomycota and Ascomycota were among the dominant fungal groups involved in degradation with very small contributions from Basidiomycota. At the end of the 2-month degradation, only 15% of the original necromass remained. The residual material was rich in amide and C-O moieties which is consistent with previous work predicting that peptidoglycans are the main residual product from microbial tissue degradation. Straight-chain fatty acids exhibited varying degradation profiles, with some fatty acids (e.g. C16, C18:1) degrading more rapidly than bulk tissue while others maintained steady concentrations relative to bulk OC (C18) or increased in concentration throughout the degradation sequence (C24). These results indicate that the turnover of fungal necromass has the potential to rapidly and significantly influence a variety of soil OC properties including C/N ratios, lipid biomarker
Real-time HIV genotyping and breaking down local HIV epidemics into phylogenetically distinct sub-epidemics may help to reveal the structure and dynamics of HIV transmission networks in communities, and aid in the design of targeted interventions for members of the acute sub-epidemics that likely fuel local HIV/AIDS epidemics.
Full Text Available Fungal exopolysaccharides (EPSs have been recognized as high value biomacromolecules for the last two decades. These products, including pullulan, scleroglucan, and botryosphaeran, have several applications in industries, pharmaceuticals, medicine, foods etc. Although fungal EPSs are highly relevant, to date information concerning fungal biosynthesis is scarce and an extensive search for new fugal species that can produce novel EPSs is still needed. In most cases, the molecular weight variations and sugar compositions of fungal EPSs are dependent to culture medium composition and different physical conditions provided during fermentation. An inclusive and illustrative review on fungal EPS is presented here. The general outline of the present work includes fungal EPS production, their compositions and applications. An emphasis is also given to listing out different fungal strains that can produce EPSs.
Holm, Lotte; Sandøe, Peter; Nielsen, Morten Ebbe Juul
To address the obesity epidemic, European researchers need to come together to find the best solutions and use their combined knowledge to provide the most innovative research ideas. By gathering more than 50 researchers and stakeholders from around Europe, we took an important step towards...... establishing strong networks and building bridges between the natural sciences and social sciences and humanities that can address obesity as a complex societal challenge and help minimise the gap between research, markets, and citizens. The objectives of the workshop were to create a cross‐European forum...
Full Text Available Protection and conservation of fungi has only recently became an issue of concern. Main motives for increased attention are uncontrolled, mass collecting of edible wild mushrooms and environmental pollution which leads to the rapid decline of their natural habitats, some of which are rich with rare and endangered species. By Serbian Nature Conservation Law 2010. there are 38 strictly protected fungal species of which 17 species are recorded in this paper. 11 of those recorded species are on European and/or National Red List of endangered fungal species. All investigated territories were in South Serbia region. This study is a contribution to conservation of protected and threatened fungi and their respective habitats in Serbia.
Prajna, Venkatesh N; Prajna, Lalitha; Muthiah, Srinivasan
Research becomes very significant and meaningful when it addresses a significant public health problem of a region. Fungal keratitis is a serious problem affecting the agrarian poor and hence requires attention from public health specialists. The approach to a public health issue should focus not only on treatment but also prevention or at least show a significant thrust to reduce the morbidity of the problem. At our institution, we have developed a special interest in fungal keratitis and tried to study it in a multitude of aspects. As we put the pieces of the puzzle together, we believe that interest will be rekindled among policymakers, clinicians, microbiologists, pharmaceutical industry, and basic scientists to work together to join forces and take up an integrative approach to managing this problem. It is also believed that the article underscores the need and importance of having a focused approach to ensuring a successful career in clinical research. PMID:29044053
El-Hossary, Ebaa M.; Cheng, Cheng; Hamed, Mostafa M.; El-Sayed Hamed, Ashraf Nageeb; Ohlsen, Knut; Hentschel, Ute; Abdelmohsen, Usama Ramadan
Highlights: • Fungal infections represent an increasing threat to human health. • Fungal infections in plants are a worldwide problem to the agricultural industry. • Diverse antifungal compounds were isolated from different marine organisms. • The number of new antifungal marine natural products is rapidly developing. • Marine sponges and bacteria are the predominant sources for antifungal compounds. Abstract: Fungal diseases represent an increasing threat to human healt...
Lactic acid bacteria (LAB) are microorganisms that have been used for centuries to prepare and improve storage of food and for ensiling of different crops for animal feed. This thesis explores the possibility of using LAB to inhibit growth of spoilage fungi in food and feed products. LAB isolates, collected from plant material or dairy products, were screened for antifungal activity in a dual culture assay. Strains with antifungal activity were identified and the fungal inhibitory activity wa...
Robbertse, B.; Tatusova, T.
The National Center for Biotechnology Information (NCBI) is well known for the nucleotide sequence archive, GenBank and sequence analysis tool BLAST. However, NCBI integrates many types of biomolecular data from variety of sources and makes it available to the scientific community as interactive web resources as well as organized releases of bulk data. These tools are available to explore and compare fungal genomes. Searching all databases with Fungi [organism] at http://www.ncbi.nlm.nih.gov/ is the quickest way to find resources of interest with fungal entries. Some tools though are resources specific and can be indirectly accessed from a particular database in the Entrez system. These include graphical viewers and comparative analysis tools such as TaxPlot, TaxMap and UniGene DDD (found via UniGene Homepage). Gene and BioProject pages also serve as portals to external data such as community annotation websites, BioGrid and UniProt. There are many different ways of accessing genomic data at NCBI. Depending on the focus and goal of research projects or the level of interest, a user would select a particular route for accessing genomic databases and resources. This review article describes methods of accessing fungal genome data and provides examples that illustrate the use of analysis tools. PMID:22737589
Full Text Available Elucidation of pathogenicity mechanisms of the most important human pathogenic fungi, Aspergillus fumigatus and Candida albicans, has gained great interest in the light of the steadily increasing number of cases of invasive fungal infections.A key feature of these infections is the interaction of the different fungal morphotypes with epithelial and immune effector cells in the human host. Because of the high level of complexity, it is necessary to describe and understand invasive fungal infection by taking a systems biological approach, i.e., by a comprehensive quantitative analysis of the non-linear and selective interactions of a large number of functionally diverse, and frequently multifunctional, sets of elements, e.g., genes, proteins, metabolites, which produce coherent and emergent behaviours in time and space. The recent advances in systems biology will now make it possible to uncover the structure and dynamics of molecular and cellular cause-effect relationships within these pathogenic interactions.We review current efforts to integrate omics and image-based data of host-pathogen interactions into network and spatio-temporal models. The modelling will help to elucidate pathogenicity mechanisms and to identify diagnostic biomarkers and potential drug targets for therapy and could thus pave the way for novel intervention strategies based on novel antifungal drugs and cell therapy.
Crawford, Jason M.; Townsend, Craig A.
Fungal aromatic polyketides constitute a large family of bioactive natural products and are synthesized by the non-reducing group of iterative polyketide synthases (NR-PKSs). Their diverse structures arise from selective enzymatic modifications of reactive enzyme-bound poly-β-keto intermediates. How iterative PKSs control starter unit selection, polyketide chain initiation and elongation, intermediate folding and cyclization, selective redox or modification reactions during assembly, and prod...
Full Text Available During the latter half of the twentieth century, fungal pathogens such as Cryptococcus neoformans were increasingly recognized as a significant threat to the health of immune compromised populations throughout the world. Until recently, the closely related species C. gattii was considered to be a low-level endemic pathogen that was confined to tropical regions such as Australia. Since 1999, C. gattii has emerged in the Pacific Northwest region of North America and has been responsible for a large disease epidemic among generally healthy individuals. The changing epidemiology of C. gattii infection is likely to be a consequence of alterations in fungal ecology and biology and illustrates its potential to cause serious human disease. This review summarizes selected biological and clinical aspects of C. gattii that are particularly relevant to the recent North American outbreak and compares these to the Australian and South American experience.
Finefield, Jennifer M.; Frisvad, Jens C.; Sherman, David H.
of numerous biogenetic, synthetic, taxonomic, and biological studies and, as such, have made a lasting impact across multiple scientific disciplines. This review covers the isolation, biosynthesis, and biological activity of these unique secondary metabolites containing the bridging bicyclo[2.2.2]diazaoctane...... ring system. Furthermore, the diverse fungal origin of these natural products is closely examined and, in many cases, updated to reflect the currently accepted fungal taxonomy....
Hussain, Hidayat; Al-Sadi, Abdullah M; Schulz, Barbara; Steinert, Michael; Khan, Ajmal; Green, Ivan R; Ahmed, Ishtiaq
The last three decades have shown that the fungi can be 'biofactories' of novel, bioactive secondary metabolites that produce numerous natural products with novel skeletons and biological activities. Particularly in the last 10 years, large numbers of antimicrobial fungal secondary metabolites have been discovered. This review provides an overview of key, defining developments of the last 10 years regarding the discovery of antimicrobial activity, chemotaxonomy and chemodiversity of fungal polyketides.
Crawford, Andrew J; Lips, Karen R; Bermingham, Eldredge
Amphibian populations around the world are experiencing unprecedented declines attributed to a chytrid fungal pathogen, Batrachochytrium dendrobatidis. Despite the severity of the crisis, quantitative analyses of the effects of the epidemic on amphibian abundance and diversity have been unavailable as a result of the lack of equivalent data collected before and following disease outbreak. We present a community-level assessment combining long-term field surveys and DNA barcode data describing changes in abundance and evolutionary diversity within the amphibian community of El Copé, Panama, following a disease epidemic and mass-mortality event. The epidemic reduced taxonomic, lineage, and phylogenetic diversity similarly. We discovered that 30 species were lost, including five undescribed species, representing 41% of total amphibian lineage diversity in El Copé. These extirpations represented 33% of the evolutionary history of amphibians within the community, and variation in the degree of population loss and decline among species was random with respect to the community phylogeny. Our approach provides a fast, economical, and informative analysis of loss in a community whether measured by species or phylogenetic diversity.
Christensen, Laurids Siig; Normann, Preben; Thykier-Nielsen, Søren
An epidemic of foot-and-mouth disease (FMD) causing a total of 23 cases in 1982-1983, primarily on the island of Funen, Denmark, was subjected to molecular epidemiological investigations. In an attempt to exploit the quasi-species nature of foot-and-mouth disease virus strains for molecular high......-resolution strain identification in order to analyse the dynamics of this epidemic, full-length VP1 coding regions were sequenced for 17 isolates collected at different farms during the epidemic. The sequence information together with epidemiological information gathered during the epidemic suggests...
Full Text Available Chronic nonhealing wounds have been heralded as a silent epidemic, causing significant morbidity and mortality especially in elderly, diabetic, and obese populations. Polymicrobial biofilms in the wound bed are hypothesized to disrupt the highly coordinated and sequential events of cutaneous healing. Both culture-dependent and -independent studies of the chronic-wound microbiome have almost exclusively focused on bacteria, omitting what we hypothesize are important fungal contributions to impaired healing and the development of complications. Here we show for the first time that fungal communities (the mycobiome in chronic wounds are predictive of healing time, associated with poor outcomes, and form mixed fungal-bacterial biofilms. We longitudinally profiled 100, nonhealing diabetic-foot ulcers with high-throughput sequencing of the pan-fungal internal transcribed spacer 1 (ITS1 locus, estimating that up to 80% of wounds contain fungi, whereas cultures performed in parallel captured only 5% of colonized wounds. The “mycobiome” was highly heterogeneous over time and between subjects. Fungal diversity increased with antibiotic administration and onset of a clinical complication. The proportions of the phylum Ascomycota were significantly greater (P = 0.015 at the beginning of the study in wounds that took >8 weeks to heal. Wound necrosis was distinctly associated with pathogenic fungal species, while taxa identified as allergenic filamentous fungi were associated with low levels of systemic inflammation. Directed culturing of wounds stably colonized by pathogens revealed that interkingdom biofilms formed between yeasts and coisolated bacteria. Combined, our analyses provide enhanced resolution of the mycobiome during impaired wound healing, its role in chronic disease, and impact on clinical outcomes.
Full Text Available Abstract Background To understand how infectious agents disseminate throughout a population it is essential to capture the social model in a realistic manner. This paper presents a novel approach to modeling the propagation of the influenza virus throughout a realistic interconnection network based on actual individual interactions which we extract from online social networks. The advantage is that these networks can be extracted from existing sources which faithfully record interactions between people in their natural environment. We additionally allow modeling the characteristics of each individual as well as customizing his daily interaction patterns by making them time-dependent. Our purpose is to understand how the infection spreads depending on the structure of the contact network and the individuals who introduce the infection in the population. This would help public health authorities to respond more efficiently to epidemics. Results We implement a scalable, fully distributed simulator and validate the epidemic model by comparing the simulation results against the data in the 2004-2005 New York State Department of Health Report (NYSDOH, with similar temporal distribution results for the number of infected individuals. We analyze the impact of different types of connection models on the virus propagation. Lastly, we analyze and compare the effects of adopting several different vaccination policies, some of them based on individual characteristics -such as age- while others targeting the super-connectors in the social model. Conclusions This paper presents an approach to modeling the propagation of the influenza virus via a realistic social model based on actual individual interactions extracted from online social networks. We implemented a scalable, fully distributed simulator and we analyzed both the dissemination of the infection and the effect of different vaccination policies on the progress of the epidemics. The epidemic values
Zaki, S M; Denning, D W
We aimed to estimate the burden of serious fungal infections in Egypt, currently unknown, based on the size of the populations at risk and available epidemiological data. Data were obtained from the World Health Organization (WHO), the Joint United Nations Programme on HIV/AIDS (UNAIDS), and published reports with clearcut denominators. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology. The population of Egypt in 2011 was ∼82,500,000; 31% children, and 8% women >60 years of age. Amongst about 21.8 million women aged 15-50 years, recurrent vulvovaginal candidiasis (≥4 episodes/year) is estimated to occur in 1.3 million (3,169/100,000 females). Using a low international average rate of 5/100,000, we estimate 4,127 cases of candidaemia, and 619 patients with intra-abdominal candidiasis. Amongst the survivors of pulmonary tuberculosis (TB) in Egypt in 2012, 319 new cases of chronic pulmonary aspergillosis (CPA) are likely, a prevalence of 1,005 post-TB and a total prevalence estimate of 3,015 CPA patients in all. Asthma is common in Egypt, affecting 9.4% of adults, 5.35 million, and so ABPA and SAFS were estimated in around 162/100,000 and 214/100,000 respectively. Invasive aspergillosis is estimated to affect 495 patients following leukaemia therapy, there are an estimated 37 cases in renal and liver transplant recipients, and an estimated 132 patients develop IA in the context of lung cancer. Amongst 641,000 COPD admissions to hospital each year, 8,337 patients develop IA. The total HIV-infected population is small, with an estimated 6,500 patients, 2,500 not on antiretroviral therapy. Amongst HIV-infected patients, 38 (0.6%) cases of cryptococcal meningitis and 125 (1.9%) cases of Pneumocystis pneumonia are estimated each year. Fungal keratitis is common, with 28-55% (mean 40%) of corneal infections being fungal, an estimated total of 11,550 cases. The present study indicates
John D Weete
Full Text Available BACKGROUND: Ergosterol has been considered the "fungal sterol" for almost 125 years; however, additional sterol data superimposed on a recent molecular phylogeny of kingdom Fungi reveals a different and more complex situation. METHODOLOGY/PRINCIPAL FINDINGS: The interpretation of sterol distribution data in a modern phylogenetic context indicates that there is a clear trend from cholesterol and other Delta(5 sterols in the earliest diverging fungal species to ergosterol in later diverging fungi. There are, however, deviations from this pattern in certain clades. Sterols of the diverse zoosporic and zygosporic forms exhibit structural diversity with cholesterol and 24-ethyl -Delta(5 sterols in zoosporic taxa, and 24-methyl sterols in zygosporic fungi. For example, each of the three monophyletic lineages of zygosporic fungi has distinctive major sterols, ergosterol in Mucorales, 22-dihydroergosterol in Dimargaritales, Harpellales, and Kickxellales (DHK clade, and 24-methyl cholesterol in Entomophthorales. Other departures from ergosterol as the dominant sterol include: 24-ethyl cholesterol in Glomeromycota, 24-ethyl cholest-7-enol and 24-ethyl-cholesta-7,24(28-dienol in rust fungi, brassicasterol in Taphrinales and hypogeous pezizalean species, and cholesterol in Pneumocystis. CONCLUSIONS/SIGNIFICANCE: Five dominant end products of sterol biosynthesis (cholesterol, ergosterol, 24-methyl cholesterol, 24-ethyl cholesterol, brassicasterol, and intermediates in the formation of 24-ethyl cholesterol, are major sterols in 175 species of Fungi. Although most fungi in the most speciose clades have ergosterol as a major sterol, sterols are more varied than currently understood, and their distribution supports certain clades of Fungi in current fungal phylogenies. In addition to the intellectual importance of understanding evolution of sterol synthesis in fungi, there is practical importance because certain antifungal drugs (e.g., azoles target reactions in
Bracho, Gustavo; Varela, Enrique; Fernández, Rolando; Ordaz, Barbara; Marzoa, Natalia; Menéndez, Jorge; García, Luis; Gilling, Esperanza; Leyva, Richard; Rufín, Reynaldo; de la Torre, Rubén; Solis, Rosa L; Batista, Niurka; Borrero, Reinier; Campa, Concepción
Leptospirosis is a zoonotic disease of major importance in the tropics where the incidence peaks in rainy seasons. Natural disasters represent a big challenge to Leptospirosis prevention strategies especially in endemic regions. Vaccination is an effective option but of reduced effectiveness in emergency situations. Homeoprophylactic interventions might help to control epidemics by using highly-diluted pathogens to induce protection in a short time scale. We report the results of a very large-scale homeoprophylaxis (HP) intervention against Leptospirosis in a dangerous epidemic situation in three provinces of Cuba in 2007. Forecast models were used to estimate possible trends of disease incidence. A homeoprophylactic formulation was prepared from dilutions of four circulating strains of Leptospirosis. This formulation was administered orally to 2.3 million persons at high risk in an epidemic in a region affected by natural disasters. The data from surveillance were used to measure the impact of the intervention by comparing with historical trends and non-intervention regions. After the homeoprophylactic intervention a significant decrease of the disease incidence was observed in the intervention regions. No such modifications were observed in non-intervention regions. In the intervention region the incidence of Leptospirosis fell below the historic median. This observation was independent of rainfall. The homeoprophylactic approach was associated with a large reduction of disease incidence and control of the epidemic. The results suggest the use of HP as a feasible tool for epidemic control, further research is warranted. 2010 Elsevier Ltd. All rights reserved.
Full Text Available Men who have sex with men (MSM and heterosexuals are the populations with the fastest growing HIV infection rates in China. We characterize the epidemic growth and age patterns between these two routes from 2004 to 2015 in Chongqing and Shenzhen, China.Data were downloaded from the National HIV/ AIDS Comprehensive Response Information Management System. For the new HIV diagnoses of heterosexuals and MSM in both cities, we estimated the growth rates by fitting different sub-exponential models. Heat maps are used to show their age patterns. We used histograms to compare these patterns by birth cohort.The MSM epidemics grew significantly in both cities. Chongqing experienced quadratic growth in HIV reported cases with an estimated growth rate of 0.086 per week and a "deceleration rate" of 0.673. HIV reported cases of MSM in Shenzhen grew even more drastically with a growth rate of 0.033 per week and "deceleration rate" of 0.794. The new infections are mainly affecting the ages of 18 to 30 in Chongqing and ages of 20 to 35 in Shenzhen. They peaked in early 1990's and mid-1990's birth cohorts in Chongqing and Shenzhen respectively. The HIV epidemic among heterosexuals grew rapidly in both cities. The growth rates were estimated as 0.02 and 0.028 in Chongqing and Shenzhen respectively whereas the "deceleration rates" were 0.878 and 0.790 in these two places. It affected mostly aged 18 to 75 in males and 18 to 65 in females in Chongqing and aged 18 to 45 in males and 18 to 50 in females in Shenzhen in 2015. In Chongqing, the heterosexual female epidemics display two peaks in HIV diagnoses in the birth cohorts of early 1950's and early 1980's, with heterosexual male epidemics peaked in early 1940's and early 1960's. The heterosexual male and female epidemics display higher rates in the birth cohort 1940-1960, than the birth cohort 1960-1990. It peaked in birth cohorts of 1950's and 1980's in Shenzhen.We revealed striking differences in epidemic growth
Full Text Available Systemic sclerosis (SSc is an autoimmune connective tissue disease involving the skin and internal organs and characterized pathologically by microvascular damage and increased deposition of connective tissue. Skin changes seen in SSc include edema, inflammation, induration, thickening, and progressive skin fibrosis. Histologically, skin fibrosis, accumulation of compact collagen in the dermis, effacement of rete pegs, infiltration by CD4+ T cells, and skin atrophy are observed. The “toxic oil syndrome” reported from Spain caused an outbreak of a scleroderma-like illness and was caused by ingestion of contaminated rapeseed cooking oil. Epidemic dropsy is caused by ingestion of mustard oil contaminated with the oil of Argemone mexicana. The major alkaloids in Argemone oil are sanguinarine and dihydrosanguinarine. These alkaloids produce widespread capillary dilatation, increased capillary permeability, and endothelial proliferation, akin to the toxic oil syndrome. Cutaneous manifestations include erythematous and tender bilaterally symmetrical pitting edema usually involving lower limbs, skin thickening and tethering, pigmentation, and presence of telangiectasias. The dermatopathology observed in epidemic dropsy includes atrophy and flattening of rete pegs, hypertrophy of and deposition of collagen, vascular dilatation and proliferation, and subcutaneous inflammation and fibrosis. Epidemic dropsy usually presents with subacute multisystem involvement, which may mimic a connective tissue disease. Skin involvement in epidemic dropsy may closely mimic cutaneous manifestations in SSc, both clinically and histologically. Thus, the clinician needs to be aware that epidemic dropsy with cutaneous involvement, especially if encountered sporadically, may be mistakenly diagnosed as scleroderma.
Frasca, M.; Rizzo, A.; Gallo, L.; Fortuna, L.; Porfiri, M.
Complex dynamical systems often exhibit collective dynamics that are well described by a reduced set of key variables in a low-dimensional space. Such a low-dimensional description offers a privileged perspective to understand the system behavior across temporal and spatial scales. In this work, we propose a data-driven approach to establish low-dimensional representations of large epidemic datasets by using a dimensionality reduction algorithm based on isometric features mapping (ISOMAP). We demonstrate our approach on synthetic data for epidemic spreading in a population of mobile individuals. We find that ISOMAP is successful in embedding high-dimensional data into a low-dimensional manifold, whose topological features are associated with the epidemic outbreak. Across a range of simulation parameters and model instances, we observe that epidemic outbreaks are embedded into a family of closed curves in a three-dimensional space, in which neighboring points pertain to instants that are close in time. The orientation of each curve is unique to a specific outbreak, and the coordinates correlate with the number of infected individuals. A low-dimensional description of epidemic spreading is expected to improve our understanding of the role of individual response on the outbreak dynamics, inform the selection of meaningful global observables, and, possibly, aid in the design of control and quarantine procedures.
Full Text Available The aim of the study was to evaluate the relationship between ocurrence of fungi in children and living environment (city - countryside, sex, age, diet, undergone diseases therapy with antibiotics and exposure to hospital environment, and to indicate children potentially vulnerable to fungal infections. The material was consisted of swabs collected from the oral cavily, the throat and the nose of healthy children, aged 6-9 and 10-15, from both urban and rural environmens. Candida albicans, the basic aetiological factor in thc majority of mycoses recorded in humans, unquestionably prevailed in the group of the 13 speciec of yeast-like fungi and yeasts isolated. Records of C. glabrata and C. krusei increasing numbers of whose strains show resistance to basic antimycoties, as well as relatively frequent records of Trichosporon beigelii, Saccharomycopsis capsularis and Saccharomyces sp., fungi whose expansiveness and enzymatic activity have been growing, may be considered disconcerting. Vulnerability to fungal infection increases following anti-bacterial antibiotic therapy in the majority of subjects regardless season or age. This is particularly true primarily of the most stable ontocoenosis of the throat. Younger children, on the other hand, are the most vulnerable foUowing infection of the respiratory system. Fungi are likely to colonise the nose in this case. Children living in the countryside who had been ll immediately prior to the collection of the material constitute the highest risk group of the occurrence of fungi in any of the ontocoenoses studied. A greater number of positive inoculations were recorded in these children in comparison to the children from the city. It may be indicative of a more extensive spectrum of natural reservoirs of fungi and the vectors of their transmission in rural areas than those in the city, lower health hygiene and lower immunity or of a more common carriage of fungi among rural children.
Krista Gebert; Greg Jones; Patty Champ; Mike Czaja; Chuck Oliver; Paul E. Cruz; Jessica. Clement
Healthy forest ecosystems provide many goods and services that are vital to human well-being. When forest ecosystems are impacted by disturbances, such as the widespread mountain pine beetle (MPB) epidemic, the services provided by these ecosystems are also affected. Likewise, management in response to large-scale forest disturbances impacts both the natural and human...
Full Text Available The article considers the influence of the military-ecological and man-caused-anthropogenic factors on the environment state and natural processes. Epidemic risks and consequences resulted from landscapic changes of the environment which arise as a result of war and destruction of ecosystems are described.
Syahrini, Intan; Sriwahyuni; Halfiani, Vera; Meurah Yuni, Syarifah; Iskandar, Taufiq; Rasudin; Ramli, Marwan
Tuberculosis is an infectious disease which has caused a large number of mortality in Indonesia. This disease is caused by Mycrobacterium tuberculosis. Besides affecting lung, this disease also affects other organs such as lymph gland, intestine, kidneys, uterus, bone, and brain. This article discusses the epidemic of tuberculosis through employing the SEIR model. Here, the population is divided into four compartments which are susceptible, exposed, infected and recovered. The susceptible population is further grouped into two which are vaccinated group and unvaccinated group. The behavior of the epidemic is investigated through analysing the equilibrium of the model. The result shows that administering vaccine to the susceptible population contributes to the reduction of the tuberculosis epidemic rate.
Nagatani, Takashi; Ichinose, Genki; Tainaka, Kei-ichi
We present an epidemic model combined with a traffic cellular automaton. Each agent or individual is either susceptible (S) or infected (I). An agent with a certain density moves to a fixed direction on one-dimensional lattice. Simulations for SIS model show that the epidemic spreads via migration. We find a dynamical phase transition between infectious and non-infectious phases. If the density exceeds the critical limit ρC, the epidemic spreads into the population. The value of ρC decreases along with the recovery rate as predicted by mean-field theory. However, this theory cannot explain the simulation result that a traffic jam strongly affects the phase transition. It is found that the minimum value of ρC corresponds to the critical value of the jamming transition.
Manzano, Marc; Calle, Eusebi; Ripoll, Jordi
Our society nowadays is governed by complex networks, examples being the power grids, telecommunication networks, biological networks, and social networks. It has become of paramount importance to understand and characterize the dynamic events (e.g. failures) that might happen in these complex...... networks. For this reason, in this paper, we propose two measures to evaluate the vulnerability of complex networks in two different dynamic multiple failure scenarios: epidemic-like and cascading failures. Firstly, we present epidemic survivability ( ES ), a new network measure that describes...... the vulnerability of each node of a network under a specific epidemic intensity. Secondly, we propose cascading survivability ( CS ), which characterizes how potentially injurious a node is according to a cascading failure scenario. Then, we show that by using the distribution of values obtained from ES and CS...
Zhang Haifeng; Small, Michael; Fu Xinchu
Models for diseases spreading are not just limited to SIS or SIR. For instance, for the spreading of AIDS/HIV, the susceptible individuals can be classified into different cases according to their immunity, and similarly, the infected individuals can be sorted into different classes according to their infectivity. Moreover, some diseases may develop through several stages. Many authors have shown that the individuals' relation can be viewed as a complex network. So in this paper, in order to better explain the dynamical behavior of epidemics, we consider different epidemic models on complex networks, and obtain the epidemic threshold for each case. Finally, we present numerical simulations for each case to verify our results.
Shi, Hong-Jing; Duan, Zhi-Sheng; Chen, Guan-Rong; Li, Rong
In this paper, a new susceptible-infected-susceptible (SIS) model on complex networks with imperfect vaccination is proposed. Two types of epidemic spreading patterns (the recovered individuals have or have not immunity) on scale-free networks are discussed. Both theoretical and numerical analyses are presented. The epidemic thresholds related to the vaccination rate, the vaccination-invalid rate and the vaccination success rate on scale-free networks are demonstrated, showing different results from the reported observations. This reveals that whether or not the epidemic can spread over a network under vaccination control is determined not only by the network structure but also by the medicine's effective duration. Moreover, for a given infective rate, the proportion of individuals to vaccinate can be calculated theoretically for the case that the recovered nodes have immunity. Finally, simulated results are presented to show how to control the disease prevalence.
In the current century, the highly developed transportation system can not only boost the economy, but also greatly accelerate the spreading of epidemics. While some epidemic diseases may infect quite a number of people ahead of our awareness, the health care resources such as vaccines and the medical staff are usually locally or even globally insufficient. In this research, with the network of major aviation routes as an example, we present a method to determine the optimal locations to allocate the medical service in order to minimize the impact of the infectious disease with limited resources. Specifically, we demonstrate that when the medical resources are insufficient, we should concentrate our efforts on the travelers with the objective of effectively controlling the spreading rate of the epidemic diseases. © 2011 Springer-Verlag Berlin Heidelberg.
Xu, Yuquan; Zhou, Tong; Zhou, Zhengfu; Su, Shiyou; Roberts, Sue A; Montfort, William R; Zeng, Jia; Chen, Ming; Zhang, Wei; Lin, Min; Zhan, Jixun; Molnár, István
Resorcylic acid lactones and dihydroxyphenylacetic acid lactones represent important pharmacophores with heat shock response and immune system modulatory activities. The biosynthesis of these fungal polyketides involves a pair of collaborating iterative polyketide synthases (iPKSs): a highly reducing iPKS with product that is further elaborated by a nonreducing iPKS (nrPKS) to yield a 1,3-benzenediol moiety bridged by a macrolactone. Biosynthesis of unreduced polyketides requires the sequestration and programmed cyclization of highly reactive poly-β-ketoacyl intermediates to channel these uncommitted, pluripotent substrates to defined subsets of the polyketide structural space. Catalyzed by product template (PT) domains of the fungal nrPKSs and discrete aromatase/cyclase enzymes in bacteria, regiospecific first-ring aldol cyclizations result in characteristically different polyketide folding modes. However, a few fungal polyketides, including the dihydroxyphenylacetic acid lactone dehydrocurvularin, derive from a folding event that is analogous to the bacterial folding mode. The structural basis of such a drastic difference in the way a PT domain acts has not been investigated until now. We report here that the fungal vs. bacterial folding mode difference is portable on creating hybrid enzymes, and we structurally characterize the resulting unnatural products. Using structure-guided active site engineering, we unravel structural contributions to regiospecific aldol condensations and show that reshaping the cyclization chamber of a PT domain by only three selected point mutations is sufficient to reprogram the dehydrocurvularin nrPKS to produce polyketides with a fungal fold. Such rational control of first-ring cyclizations will facilitate efforts to the engineered biosynthesis of novel chemical diversity from natural unreduced polyketides.
Fungal pathogens severely impact global food and fibre crop security. Fungal species that cause plant diseases have mostly been recognized based on their morphology. In general, morphological descriptions remain disconnected from crucially important knowledge such as mating types, host specificity, life cycle stages and population structures. The majority of current fungal species descriptions lack even the most basic genetic data that could address at least some of these issues. Such information is essential for accurate fungal identifications, to link critical metadata and to understand the real and potential impact of fungal pathogens on production and natural ecosystems. Because international trade in plant products and introduction of pathogens to new areas is likely to continue, the manner in which fungal pathogens are identified should urgently be reconsidered. The technologies that would provide appropriate information for biosecurity and quarantine already exist, yet the scientific community and the regulatory authorities are slow to embrace them. International agreements are urgently needed to enforce new guidelines for describing plant pathogenic fungi (including key DNA information), to ensure availability of relevant data and to modernize the phytosanitary systems that must deal with the risks relating to trade-associated plant pathogens. This article is part of the themed issue ‘Tackling emerging fungal threats to animal health, food security and ecosystem resilience’. PMID:28080994
Singh, Lamabam Peter
Fungal symbionts have been found to be associated with every plant studied in the natural ecosystem, where they colonize and reside entirely or partially in the internal tissues of their host plant. Fungal endophytes can express/form a range of different lifestyle/relationships with different host including symbiotic, mutualistic, commensalistic and parasitic in response to host genotype and environmental factors. In mutualistic association fungal endophyte can enhance growth, increase reproductive success and confer biotic and abiotic stress tolerance to its host plant. Since abiotic stress such as, drought, high soil salinity, heat, cold, oxidative stress and heavy metal toxicity is the common adverse environmental conditions that affect and limit crop productivity worldwide. It may be a promising alternative strategy to exploit fungal endophytes to overcome the limitations to crop production brought by abiotic stress. There is an increasing interest in developing the potential biotechnological applications of fungal endophytes for improving plant stress tolerance and sustainable production of food crops. Here we have described the fungal symbioses, fungal symbionts and their role in abiotic stress tolerance. A putative mechanism of stress tolerance by symbionts has also been covered. PMID:21512319
Rodolphe Elie Gozlan
Full Text Available Despite increasingly sophisticated microbiological techniques, and long after the first discovery of microbes, basic knowledge is still lacking to fully appreciate the ecological importance of microbial parasites in fish. This is likely due to the nature of their habitats as many species of fish suffer from living beneath turbid water away from easy recording. However, fishes represent key ecosystem services for millions of people around the world and the absence of a functional ecological understanding of viruses, prokaryotes, and small eukaryotes in the maintenance of fish populations and of their diversity represents an inherent barrier to aquatic conservation and food security. Among recent emerging infectious diseases responsible for severe population declines in plant and animal taxa, fungal and fungal-like microbes have emerged as significant contributors. Here, we review the current knowledge gaps of fungal and fungal-like parasites and pathogens in fish and put them into an ecological perspective with direct implications for the monitoring of fungal fish pathogens in the wild, their phylogeography as well as their associated ecological impact on fish populations. With increasing fish movement around the world for farming, releases into the wild for sport fishing and human-driven habitat changes, it is expected, along with improved environmental monitoring of fungal and fungal-like infections, that the full extent of the impact of these pathogens on wild fish populations will soon emerge as a major threat to freshwater biodiversity.
Pasha, Ahmed Khurshid; Lee, Justin Z; Low, See-Wei; Desai, Hem; Lee, Kwan S; Al Mohajer, Mayar
Fungal endocarditis is an extremely debilitating disease associated with high morbidity and mortality. Candida spp. are the most common isolated organisms in fungal endocarditis. It is most prevalent in patients who are immunosuppressed and intravenous drug users. Most patients present with constitutional symptoms, which are indistinguishable from bacterial endocarditis, hence a high index of suspicion is required for pursuing diagnosis. Diagnosis of fungal endocarditis can be very challenging: most of the time, blood cultures are negative or take a long time to yield growth. Fungal endocarditis mandates an aggressive treatment strategy. A medical and surgical combined approach is the cornerstone of therapy. Copyright © 2016 Elsevier Inc. All rights reserved.
Jahn, Linda; Schafhauser, Thomas; Wibberg, Daniel
Fungal aromatic polyketides display a very diverse and widespread group of natural products. Due to their excellent light absorption properties and widely studied biological activities, they offer numerous application for food, textile and pharmaceutical industry. The biosynthetic pathways of fun...
Parkes-Ratanshi, R; Achan, B; Kwizera, R; Kambugu, A; Meya, D; Denning, D W
The HIV epidemic in Uganda has highlighted Cryptococcus and Candida infections as important opportunistic fungal infections. However, the burden of other fungal diseases is not well described. We aimed to estimate the burden of fungal infections in Uganda. All epidemiological papers of fungal diseases in Uganda were reviewed. Where there is no Ugandan data, global or East African data were used. Recurrent vaginal candidiasis is estimated to occur in 375 540 Uganda women per year; Candida in pregnant women affects up to 651,600 women per year. There are around 45,000 HIV-related oral and oesophageal candidosis cases per year. There are up to 3000 cases per year of post-TB chronic pulmonary aspergillosis. There are an estimated 40,392 people with asthma-related fungal conditions. An estimated 1,300,000 cases of tinea capitis occur in school children yearly in Uganda. There are approximately 800 HIV-positive adults with Pneumocystis jirovecii pneumonia (PJP) annually and up to 42 000 children with PJP per year. There are an estimated 4000 cryptococcal cases annually. There are an estimated 2.5 million fungal infections per year in Uganda. Cryptococcus and PJP cause around 28,000 deaths in adults and children per year. We propose replicating the model of research around cryptococcal disease to investigate and development management strategies for other fungal diseases in Uganda. © 2015 Blackwell Verlag GmbH.
Elaine O Nsoesie
Full Text Available Individual-based epidemiology models are increasingly used in the study of influenza epidemics. Several studies on influenza dynamics and evaluation of intervention measures have used the same incubation and infectious period distribution parameters based on the natural history of influenza. A sensitivity analysis evaluating the influence of slight changes to these parameters (in addition to the transmissibility would be useful for future studies and real-time modeling during an influenza pandemic.In this study, we examined individual and joint effects of parameters and ranked parameters based on their influence on the dynamics of simulated epidemics. We also compared the sensitivity of the model across synthetic social networks for Montgomery County in Virginia and New York City (and surrounding metropolitan regions with demographic and rural-urban differences. In addition, we studied the effects of changing the mean infectious period on age-specific epidemics. The research was performed from a public health standpoint using three relevant measures: time to peak, peak infected proportion and total attack rate. We also used statistical methods in the design and analysis of the experiments. The results showed that: (i minute changes in the transmissibility and mean infectious period significantly influenced the attack rate; (ii the mean of the incubation period distribution appeared to be sufficient for determining its effects on the dynamics of epidemics; (iii the infectious period distribution had the strongest influence on the structure of the epidemic curves; (iv the sensitivity of the individual-based model was consistent across social networks investigated in this study and (v age-specific epidemics were sensitive to changes in the mean infectious period irrespective of the susceptibility of the other age groups. These findings suggest that small changes in some of the disease model parameters can significantly influence the uncertainty
Vederas, John C
This viewpoint on biosynthesis of reduced polyketides in fungi traces evolution of the research area over more than 4 decades. It is a companion to the related articles by two personal and scientific friends with whom there has been free exchange of ideas for over 30 years. Beginning with very rudimentary knowledge about assembly of such natural products, developments using stable isotope labelling and subsequently identification of biosynthetic genes, led to understanding of the processive nature of polyketide formation. Recent expression and isolation of fungal iterative polyketide synthase enzymes has enabled more detailed exploration of the mechanisms of these fascinating molecular machines.
Wang, Z K; Yang, Y S; Stefka, A T; Sun, G; Peng, L H
The role of the fungal microbiota in digestive diseases is poorly defined, but is becoming better understood due to advances in metagenomics. To review the gastrointestinal fungal microbiota and its relationship with digestive diseases. Search of the literature using PubMed and MEDLINE databases. Subject headings including 'fungal-bacterial interactions', 'mycotoxins', 'immunity to fungi', 'fungal infection', 'fungal microbiota', 'mycobiome' and 'digestive diseases' were used. The fungal microbiota is an integral part of the gastrointestinal microecosystem with up to 10(6) microorganisms per gram of faeces. Next-generation sequencing of the fungal 18S rRNA gene has allowed better characterisation of the gastrointestinal mycobiome. Numerous interactions between fungi and bacteria and the complex immune response to gastrointestinal commensal or pathogenic fungi all impact on the pathophysiology of inflammatory bowel disease and other gastrointestinal inflammatory entities such as peptic ulcers. Mycotoxins generated as fungal metabolites contribute to disturbances of gastrointestinal barrier and immune functions and are associated with chronic intestinal inflammatory conditions as well as hepatocellular and oesophagogastric cancer. Systemic and gastrointestinal disease can also lead to secondary fungal infections. Fungal genomic databases and methodologies need to be further developed and will allow a much better understanding of the diversity and function of the mycobiome in gastrointestinal inflammation, tumourigenesis, liver cirrhosis and transplantation, and its alteration as a consequence of antibiotic therapy and chemotherapy. The fungal microbiota and its metabolites impact gastrointestinal function and contribute to the pathogenesis of digestive diseases. Further metagenomic analyses of the gastrointestinal mycobiome in health and disease is needed. © 2014 John Wiley & Sons Ltd.
Mansour, I.; Heppell, C. M.; McKew, B.; Dumbrell, A.; Whitby, C. B.; Veresoglou, S.; Leung, G.; Binley, A. M.; Lansdown, K.; Trimmer, M.; Olde, L.; Rillig, M.
community structure. Since riverine ecosystems are often subject to high levels of natural and anthropogenic stressors, it is imperative to understand the mechanisms regulating riverine fungal communities before appropriate management options can be suggested.
Seyedmousavi, S; Guillot, J; Tolooe, A; Verweij, P E; de Hoog, G S
Zoonotic fungi can be naturally transmitted between animals and humans, and in some cases cause significant public health problems. A number of mycoses associated with zoonotic transmission are among the group of the most common fungal diseases, worldwide. It is, however, notable that some fungal diseases with zoonotic potential have lacked adequate attention in international public health efforts, leading to insufficient attention on their preventive strategies. This review aims to highlight some mycoses whose zoonotic potential received less attention, including infections caused by Talaromyces (Penicillium) marneffei, Lacazia loboi, Emmonsia spp., Basidiobolus ranarum, Conidiobolus spp. and Paracoccidioides brasiliensis. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Austin, Cindy L; Finley, Phillip J; Mikkelson, Debbie R; Tibbs, Brian
This article reviews four immunocompetent patients who developed a rare fungal infection, mucormycosis, secondary to multiple traumatic injuries sustained during an EF-5 tornado in Joplin, MO. Commonly found in soil and decaying organic matter, mucorales are fungi associated with soft tissue and cutaneous infections. Onset of this fungal infection can occur without clinical signs, presenting several days to several weeks after injury, delaying diagnosis. A multidisciplinary treatment approach including aggressive antifungal therapy and aggressive surgical debridement is critical. This diagnosis should be considered in all patients presenting with injuries sustained from high-velocity embedment of debris such as natural disasters or explosions. We present four cases of mucormycosis, species Apophysomyces trapeziformis. Data reported includes predisposing factors, number of days between injury and diagnosis of mucormycosis, surgical treatment, antifungal therapy, outcomes, and potential risk factors that may have contributed to the development of mucormycosis.
Subash C. B. Gopinath
Full Text Available Lipases are water-soluble enzymes that act on insoluble substrates and catalyze the hydrolysis of long-chain triglycerides. Lipases play a vital role in the food, detergent, chemical, and pharmaceutical industries. In the past, fungal lipases gained significant attention in the industries due to their substrate specificity and stability under varied chemical and physical conditions. Fungal enzymes are extracellular in nature, and they can be extracted easily, which significantly reduces the cost and makes this source preferable over bacteria. Soil contaminated with spillage from the products of oil and dairy harbors fungal species, which have the potential to secrete lipases to degrade fats and oils. Herein, the strategies involved in the characterization of fungal lipases, capable of degrading fatty substances, are narrated with a focus on further applications.
Xue, Chaoyang; Tada, Yasuomi; Dong, Xinnian; Heitman, Joseph
Cryptococcus is a globally distributed human fungal pathogen that primarily afflicts immunocompromised individuals. How and why this human fungal pathogen associates with plants and how this environmental niche influences its life cycle remains a mystery. We established Cryptococcus-Arabidopsis and Cryptococcus-Eucalyptus systems and discovered that Cryptococcus proliferates and mates on plant surfaces. Mating efficiency of C. gattii was markedly enhanced on plants and myo-inositol and indole acetic acid were specific plant products that stimulated mating. On Arabidopsis, dwarfing and chlorosis were observed following infection with a fungal mixture of two opposite mating-type strains, but not with either mating-type alone. This infection process is countered by the plant jasmonate-mediated defense mechanism. These findings reveal that Cryptococcus can parasitically interact with plants to complete its sexual cycle, which may impact an understanding of the origin and evolution of both plant and animal fungal pathogens in nature.
Gopinath, Subash C. B.; Anbu, Periasamy; Lakshmipriya, Thangavel; Hilda, Azariah
Lipases are water-soluble enzymes that act on insoluble substrates and catalyze the hydrolysis of long-chain triglycerides. Lipases play a vital role in the food, detergent, chemical, and pharmaceutical industries. In the past, fungal lipases gained significant attention in the industries due to their substrate specificity and stability under varied chemical and physical conditions. Fungal enzymes are extracellular in nature, and they can be extracted easily, which significantly reduces the cost and makes this source preferable over bacteria. Soil contaminated with spillage from the products of oil and dairy harbors fungal species, which have the potential to secrete lipases to degrade fats and oils. Herein, the strategies involved in the characterization of fungal lipases, capable of degrading fatty substances, are narrated with a focus on further applications. PMID:23865040
Full Text Available Fungal infections of the orbit can lead to grave complications. Although the primary site of inoculation of the infective organism is frequently the sinuses, the patients can initially present to the ophthalmologist with ocular signs and symptoms. Due to its varied and nonspecific clinical features, especially in the early stages, patients are frequently misdiagnosed and even treated with steroids which worsen the situation leading to dire consequences. Ophthalmologists should be familiar with the clinical spectrum of disease and the variable presentation of this infection, as early diagnosis and rapid institution of appropriate therapy are crucial elements in the management of this invasive sino-orbital infection. In this review, relevant clinical, microbiological, and imaging findings are discussed along with the current consensus on local and systemic management. We review the recent literature and provide a comprehensive analysis. In the immunocompromised, as well as in healthy patients, a high index of suspicion must be maintained as delay in diagnosis of fungal pathology may lead to disfiguring morbidity or even mortality. Obtaining adequate diagnostic material for pathological and microbiological examination is critical. Newer methods of therapy, particularly oral voriconazole and topical amphotericin B, may be beneficial in selected patients.
Campbell, R N
Thirty soilborne viruses or virus-like agents are transmitted by five species of fungal vectors. Ten polyhedral viruses, of which nine are in the family Tombusviridae, are acquired in the in vitro manner and do not occur within the resting spores of their vectors, Olpidium brassicae and O. bornovanus. Fungal vectors for other viruses in the family should be sought even though tombusviruses are reputed to be soil transmitted without a vector. Eighteen rod-shaped viruses belonging to the furo- and bymovirus groups and to an unclassified group are acquired in the in vivo manner and survive within the resting spores of their vector, O. brassicae, Polymyxa graminis, P. betae, and Spongospora subterranea. The viral coat protein has an essential role in in vitro transmission. With in vivo transmission a site in the coat protein-read through protein (CP-RT) of beet necrotic yellow vein furovirus determines vector transmissibility as does a site in a similar 98-kDa polyprotein of barley mild mosaic bymovirus. The mechanisms by which virions move (or are moved) into and out of the protoplasm of zoospores or of thalli needs study.
Tian, Huidong; Yan, Chuan; Xu, Lei; Büntgen, Ulf; Stenseth, Nils C; Zhang, Zhibin
A wide range of climate change-induced effects have been implicated in the prevalence of infectious diseases. Disentangling causes and consequences, however, remains particularly challenging at historical time scales, for which the quality and quantity of most of the available natural proxy archives and written documentary sources often decline. Here, we reconstruct the spatiotemporal occurrence patterns of human epidemics for large parts of China and most of the last two millennia. Cold and dry climate conditions indirectly increased the prevalence of epidemics through the influences of locusts and famines. Our results further reveal that low-frequency, long-term temperature trends mainly contributed to negative associations with epidemics, while positive associations of epidemics with droughts, floods, locusts, and famines mainly coincided with both higher and lower frequency temperature variations. Nevertheless, unstable relationships between human epidemics and temperature changes were observed on relatively smaller time scales. Our study suggests that an intertwined, direct, and indirect array of biological, ecological, and societal responses to different aspects of past climatic changes strongly depended on the frequency domain and study period chosen.
Full Text Available The original four-stage model of the cigarette epidemic has been extended with diffusion of innovations theory to reflect socio-economic differences in cigarette use. Recently, two revisions of the model have been proposed: (1 separate analysis of the epidemic stages for men and women, in order to improve generalization to developing countries, and; (2 addition of a fifth stage to the smoking epidemic, in order to account for the persistence of smoking in disadvantaged social groups. By developing a cohort perspective spanning a 35-year time period in France and the USA, we uncover distinctive features which challenge the currently held vision on the evolution of smoking inequalities within the framework of the cigarette epidemic. We argue that the reason for which the model may not be fit to the lower educated is that the imitation mechanism underlying the diffusion of innovations works well with regard to adoption of the habit, but is much less relevant with regard to its rejection. Based on those observations, we support the idea that the nature and timing of the epidemic differs enough to treat the stages separately for high and low education groups, and discuss policy implications.
Full Text Available . 2005. Climate Drives the Meningitis Epidemics Onset in West Africa. PLoS Medicine, 2: 0043-0049. TAMPLIN, M.L., GAUZENS, A.L., HUQ,A., SACK, D.A. & COLWELL, R.R. 1990. COLWELL. Attachment of Vibrio cholerae Serogroup 01 to Zooplankton...
Sandoval, Ruben; Martinez, Douglas R.
Recently, incidents of police abuse against Hispanics have increased so rapidly that the phenomenon has been called an epidemic. Of special concern to Hispanic leaders is the lack of Federal intervention in these police brutality cases. A list of 56 documented cases involving police brutality against Hispanics is included. (Author/NQ)
Audelin, Anne Margrethe; Cowan, Susan A; Obel, Niels
BACKGROUND:: In Denmark 300 new individuals are diagnosed with HIV every year, despite decades of public health campaigns aimed to raise awareness of potential risk behaviour for HIV transmission. It is important to identify the driving forces of the epidemic, to enable more targeted campaigns...
Overdose related to prescription opioids has become an epidemic. This podcast discusses the risks of this type of drug sometimes used to treat pain, and how to protect yourself. . Created: 4/19/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP). Date Released: 4/19/2016.
Carton, H; Kayembe, K; Kabeya; Odio; Billiau, A; Maertens, K
Epidemiological findings of twenty sporadic cases of epidemic spastic paraparesis (buka-buka) in three areas of Bandundu (Zaire) are reported. These findings suggest the involvement of an infectious agent and do not support the hypothesis of a dietary cyanide intoxication, which has been advanced to explain the outbreak of a very similar disease (Mantakassa) in Mozambique.
Argues that public perceptions of an epidemic of school violence are media-induced; asserts that violence in schools declined during the 1990s; supports assertion with evidence from the National School Safety Center; states the estimates of bullying in school are exaggerated. (PKP)
Malawi Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 13, No 1 (2001) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Cholera Epidemic Control. R Zachariah. Full Text: EMAIL FREE ...
Issue/problem: After disasters, terrorist attacks and wars social epidemics of medically unexplained physical symptoms/syndromes (ups) are often seen. In modern times people feel more vulnerable and especially under pressure of those incidents, everyday symptoms are interpreted as disease and
First page Back Continue Last page Overview Graphics. Epidemics can be prevented with a Doctor on Call. A potential epidemic of Chicken Pox was halted by a simple email to the right people. Instant response from the Government Doctors.
receiving immunosuppressive therapy, and patients with chronic obstructive lung disease (1). Fungi also play a role in allergic fungal disease such as allergic broncho- pulmonary Aspergilosis (ABPA) and chronic or deep tissue infections. The laboratory diagnosis of fungal infection starts with a simple potassium hydroxide.
Tropospheric ozone has been proven to trigger biochemical plant responses that are similar to the ones induced by an attack of fungal pathogens, i.e. it resembles fungal elicitors. This suggests that ozone can represent a valid tool for the study of stress responses and induction of resistance to pathogens. This review ...
Heshof, R.; Jylhä, S.; Haarmann, T.; Jørgensen, A.L.W.; Dalsgaard, T.K.; Graaff, de L.H.
Lipoxygenases (LOXs) are well-studied enzymes in plants and mammals. However, fungal LOXs are less studied. In this study, we have compared fungal LOX protein sequences to all known characterized LOXs. For this, a script was written using Shell commands to extract sequences from the NCBI database
Evgeny P. Kuz' michevl; Ella s. Sokolova; Elena G. Kulikova
Describes common fungal diseases of Russian forests, including diagnostic signs and symptoms, pathogen biology, damage caused by the disease, and methods of control. The fungal diseases are divided into two groups: those that are the most common in Russian forests and those that are found only in Russia. Within each group, diseases are subdivided by plant organ...
Osaka, Shunsuke; Okuzumi, Katsuko; Koide, Shota; Tamai, Kiyoko; Sato, Tomoaki; Tanimoto, Koichi; Tomita, Haruyoshi; Suzuki, Masahiro; Nagano, Yukiko; Shibayama, Keigo; Arakawa, Yoshichika; Nagano, Noriyuki
The decline in methicillin-resistant Staphylococcus aureus (MRSA) isolation rates has become a general observation worldwide, including Japan. We hypothesized that some genetic shift in MRSA might cause this phenomenon, and therefore we investigated the genetic profiles among MRSA clinical isolates obtained from three different epidemic phases in Japan. A total of 353 MRSA isolates were selected from 202 medical facilities in 1990 (pre-epidemic phase), 2004 (epidemic phase) and 2016 (post-epidemic phase). Molecular typing was performed by PCR detection of 22 genes using the polymerase chain reaction (PCR)-based ORF typing (POT) system, including an additional eight genes including small genomic islets and seven toxin genes. Isolates with a POT1 of score 93, identified as presumed clonal complex (pCC)5-staphylococcal cassette chromosome mec (SCCmec) type II including ST5-SCCmec type II New York/Japan clone, represented the major epidemic MRSA lineage in 1990 and 2004. In 2016, however, a marked decrease in isolates with a POT1 score of 93, along with changes in the epidemiology of toxin genes carried, was noted, where the carriers of tst genes including the tst-sec combination were markedly reduced, and those possessing the seb gene alone were markedly increased. Rather, isolates with a POT1 score of 106, including pCC1 or pCC8 among the isolates with SCCmec type IV, which often links to community-associated MRSA, were predominant. Interestingly, the pCC1 and pCC8 lineages were related to sea and tst-sec carriage, respectively. Over time, a transition in MRSA genetic profiles from a POT1 score of 93 in 1990 and 2004 to 106 in 2014 was found in Japan.
Full Text Available The stress of living conditions, similar to infections, alters animal immunity. High population density is empirically considered to induce prophylactic immunity to reduce the infection risk, which was challenged by a model of low connectivity between infectious and susceptible individuals in crowded animals. The migratory locust, which exhibits polyphenism through gregarious and solitary phases in response to population density and displays different resistance to fungal biopesticide (Metarhizium anisopliae, was used to observe the prophylactic immunity of crowded animals. We applied an RNA-sequencing assay to investigate differential expression in fat body samples of gregarious and solitary locusts before and after infection. Solitary locusts devoted at least twice the number of genes for combating M. anisopliae infection than gregarious locusts. The transcription of immune molecules such as pattern recognition proteins, protease inhibitors, and anti-oxidation proteins, was increased in prophylactic immunity of gregarious locusts. The differentially expressed transcripts reducing gregarious locust susceptibility to M. anisopliae were confirmed at the transcriptional and translational level. Further investigation revealed that locust GNBP3 was susceptible to proteolysis while GNBP1, induced by M. anisopliae infection, resisted proteolysis. Silencing of gnbp3 by RNAi significantly shortened the life span of gregarious locusts but not solitary locusts. By contrast, gnbp1 silencing did not affect the life span of both gregarious and solitary locusts after M. anisopliae infection. Thus, the GNBP3-dependent immune responses were involved in the phenotypic resistance of gregarious locusts to fungal infection, but were redundant in solitary locusts. Our results indicated that gregarious locusts prophylactically activated upstream modulators of immune cascades rather than downstream effectors, preferring to quarantine rather than eliminate pathogens to
Haugwitz, Merian Skouw
Global change will affect the functioning and structure of terrestrial ecosystems and since soil fungi are key players in organic matter decomposition and nutrient turnover, shifts in fungal community composition might have a strong impact on soil functioning. The main focus of this thesis...... was therefore to investigate the impact of global environmental changes on soil fungal communities in a temperate and subartic heath ecosystem. The objective was further to determine global change effects on major functional groups of fungi and analyze the influence of fungal community changes on soil carbon...... and nutrient availability and storage. By combining molecular methods such as 454 pyrosequencing and quantitative PCR of fungal ITS amplicons with analyses of soil enzymes, nutrient pools of carbon, nitrogen and phosphorus we were able to characterize soil fungal communities as well as their impact on nutrient...
Chiyori T Urabe
Full Text Available In recent years, serious infectious diseases tend to transcend national borders and widely spread in a global scale. The incidence and prevalence of epidemics are highly influenced not only by pathogen-dependent disease characteristics such as the force of infection, the latent period, and the infectious period, but also by human mobility and contact patterns. However, the effect of heterogeneous mobility of individuals on epidemic outcomes is not fully understood. Here, we aim to elucidate how spatial mobility of individuals contributes to the final epidemic size in a spatial susceptible-exposed-infectious-recovered (SEIR model with mobile individuals in a square lattice. After illustrating the interplay between the mobility parameters and the other parameters on the spatial epidemic spreading, we propose an index as a function of system parameters, which largely governs the final epidemic size. The main contribution of this study is to show that the proposed index is useful for estimating how parameter scaling affects the final epidemic size. To demonstrate the effectiveness of the proposed index, we show that there is a positive correlation between the proposed index computed with the real data of human airline travels and the actual number of positive incident cases of influenza B in the entire world, implying that the growing incidence of influenza B is attributed to increased human mobility.
Gesser-Edelsburg, Anat; Shir-Raz, Yaffa; Bar-Lev, Oshrat Sassoni; James, James J; Green, Manfred S
Our aim was to examine in what terms leading newspapers' online sites described the current Ebola crisis. We employed a quantitative content analysis of terms attributed to Ebola. We found and analyzed 582 articles published between March 23 and September 30, 2014, on the online websites of 3 newspapers: The New York Times, Daily Mail, and Ynet. Our theoretical framework drew from the fields of health communication and emerging infectious disease communication, including such concepts as framing media literacy, risk signatures, and mental models. We found that outbreak and epidemic were used interchangeably in the articles. From September 16, 2014, onward, epidemic predominated, corresponding to when President Barack Obama explicitly referred to Ebola as an epidemic. Prior to Obama's speech, 86.8% of the articles (323) used the term outbreak and only 8.6% (32) used the term epidemic. Subsequently, both terms were used almost the same amount: 53.8% of the articles (113) used the term outbreak and 53.3% (112) used the term epidemic. Effective communication is crucial during public health emergencies such as Ebola, because language framing affects the decision-making process of social judgments and actions. The choice of one term (outbreak) over another (epidemic) can create different conceptualizations of the disease, thereby influencing the risk signature. (Disaster Med Public Health Preparedness. 2016;10:669-673).
Bassett, M T; Mhloyi, M
As the AIDS epidemic in Africa assumes major proportions, the need to understand the social context in which heterosexual transmission occurs takes on urgent importance. In this article we explore how the intersection of traditional culture with the colonial legacy and present-day political economy has influenced family structure and sexual relations, and particularly the social position of women. Drawing on Zimbabwe's historical experience, we show how land expropriation, rural impoverishment, and the forcible introduction of male migrant labor fostered new patterns of sexual relations, characterized by multiple partners. Traditional patriarchal values reinterpreted in European law resulted in further subjugation of women as even limited rights to ownership were withdrawn. For many women, sexual relations with men, either within marriage (for the majority) or outside, become inextricably linked to economic and social survival. In this setting, all sexually transmitted diseases became rampant, including genital ulcer, which facilitates transmission of the human immunodeficiency virus (HIV). Intervention programs to halt the spread of AIDS need to take into the account the epidemic's historical roots and social nature. For example, efforts to reduce risk of HIV transmission should seek to expand women's limited options, both technically (e.g., by providing alternatives to condoms) and socially (e.g., by promoting employment).
Meystre-Agustoni, G; Van Melle, G; Chave, J P; Martin, J; Billo, N; Glauser, M P; Francioli, P
A two-phase survey was conducted in the Canton of Vaud among the 1006 registered private practitioners (response rate 98%). The first phase aimed at determining the proportion of these physicians involved in the care of HIV+ persons. The results showed that 43% of the practitioners had been consulted by HIV+ patients. In the second phase, all institutions (hospitals, prisons and IV-drug user rehabilitation and testing centers) and a representative sample of the physicians with HIV+ patients were asked about the transmission category of their HIV+ patients. A mathematical method was used to estimate the true number of known HIV+ individuals by December 1988. Approximately 60% of the HIV+ persons had been seen exclusively by the private practitioners. IV-drug users represented 57% of all HIV+ persons compared to only 27% of the AIDS cases registered in 1988, suggesting that an important change in the transmission categories of AIDS cases is to be expected in the near future. These observations underscore the evolving nature of the HIV epidemic on the one hand, and the crucial role of the private practitioners in the prevention of the HIV infection on the other. This also points to the need for methods specifically designed to monitor HIV and AIDS epidemics respectively.
Transferring the Malaria Epidemic Prediction Model to Users in East Africa. In the highlands of East Africa, epidemic malaria is an emerging climate-related hazard that urgently needs addressing. Malaria incidence increased by 337% during the 1987 epidemic in Rwanda. In Tanzania, Uganda and Kenya, malaria incidence ...
Santhosh G. S
Full Text Available BACKGROUND Nasal polyposis is a disease entity characterised by formation of pseudoedema of sinonasal mucus membrane progressing to form polyps. It presents clinically with nasal obstruction and fleshy masses in the nasal cavity. The nasal mucosa reacts to formation of polypi in allergic fungal sinusitis also. The present study is an attempt to demonstrate possible fungal elements from the polypi removed during surgery by KOH study and HPE study. The aim of the study is to find out the incidence of fungal elements in sinonasal polyposis. MATERIALS AND METHODS 50 patients attending the ENT OPD for nasal obstruction and showing polypi on anterior rhinoscopy were selected. All the patients were subjected to surgery and specimens collected were subjected to KOH study and histopathology to demonstrate fungal elements. RESULTS Among 50 patients, the age range was from 9-57 years; mean age- 36.46 years. The male-to-female ratio was 1.5:1. Deviated nasal septum was found in 38% of patients. Among the unilateral cases, 47% were antrochoanal polyps and 53% were ethmoid polyps. Out of 50 patients, only 3 specimens were positive for fungal elements with KOH study and only 2 cases with fungal culture. Thus, the incidence of fungal elements in sinonasal polyposis was 6%. CONCLUSION The incidence of fungal elements in sinonasal polyposis was 6%. Histopathological examination of polypectomy specimen was negative for invasive fungal disease and showed inflammatory changes only. There is no difference in the detection of the presence of fungal by two methods.
Duggal, Praveen; Wise, Sarah K
Invasive fungal rhinosinusitis (IFRS) is a disease of the paranasal sinuses and nasal cavity that typically affects immunocompromised patients in the acute fulminant form. Early symptoms can often mimic rhinosinusitis, while late symptoms can cause significant morbidity and mortality. Swelling and mucosal thickening can quickly progress to pale or necrotic tissue in the nasal cavity and sinuses, and the disease can rapidly spread and invade the palate, orbit, cavernous sinus, cranial nerves, skull base, carotid artery, and brain. IFRS can be life threatening if left undiagnosed or untreated. While the acute fulminant form of IFRS is the most rapidly progressive and destructive, granulomatous and chronic forms also exist. Diagnosis of IFRS often mandates imaging studies in conjunction with clinical, endoscopic, and histopathological examination. Treatment of IFRS consists of reversing the underlying immunosuppression, antifungal therapy, and aggressive surgical debridement. With early diagnosis and treatment, IFRS can be treated and increase patient survival.
Duggal, Praveen; Wise, Sarah K
Invasive fungal rhinosinusitis (IFRS) is a disease of the paranasal sinuses and nasal cavity that typically affects immunocompromised patients in the acute fulminant form. Early symptoms can often mimic rhinosinusitis, while late symptoms can cause significant morbidity and mortality. Swelling and mucosal thickening can quickly progress to pale or necrotic tissue in the nasal cavity and sinuses, and the disease can rapidly spread and invade the palate, orbit, cavernous sinus, cranial nerves, skull base, carotid artery, and brain. IFRS can be life threatening if left undiagnosed or untreated. While the acute fulminant form of IFRS is the most rapidly progressive and destructive, granulomatous and chronic forms also exist. Diagnosis of IFRS often mandates imaging studies in conjunction with clinical, endoscopic, and histopathological examination. Treatment of IFRS consists of reversing the underlying immunosuppression, antifungal therapy, and aggressive surgical debridement. With early diagnosis and treatment, IFRS can be treated and increase patient survival.
Macellaro, Gemma; Pezzella, Cinzia; Cicatiello, Paola; Sannia, Giovanni; Piscitelli, Alessandra
Over the past decades, water pollution by trace organic compounds (ng/L) has become one of the key environmental issues in developed countries. This is the case of the emerging contaminants called endocrine disrupting compounds (EDCs). EDCs are a new class of environmental pollutants able to mimic or antagonize the effects of endogenous hormones, and are recently drawing scientific and public attention. Their widespread presence in the environment solicits the need of their removal from the contaminated sites. One promising approach to face this challenge consists in the use of enzymatic systems able to react with these molecules. Among the possible enzymes, oxidative enzymes are attracting increasing attention because of their versatility, the possibility to produce them on large scale, and to modify their properties. In this study five different EDCs were treated with four different fungal laccases, also in the presence of both synthetic and natural mediators. Mediators significantly increased the efficiency of the enzymatic treatment, promoting the degradation of substrates recalcitrant to laccase oxidation. The laccase showing the best performances was chosen to further investigate its oxidative capabilities against micropollutant mixtures. Improvement of enzyme performances in nonylphenol degradation rate was achieved through immobilization on glass beads.
Full Text Available Invasive fungal infection (IFI is a rare but serious complication of traumatic injury. The purpose of this article is to review the epidemiology, natural history, mycology, risk factors, diagnosis, treatment, and outcomes associated with post-traumatic IFI in military and civilian populations. The epidemiology of post-traumatic IFI is poorly characterized, but incidence appears to be rising. Patients often suffer from severe injuries and require extensive medical interventions. Fungi belonging to the order Mucorales are responsible for most post-traumatic IFI in both civilian and military populations. Risk factors differ between these cohorts but include specific injury patterns and comorbidities. Diagnosis of post-traumatic IFI typically follows positive laboratory results in the appropriate clinical context. The gold standard of treatment is surgical debridement in addition to systemic antifungal therapy. Patients with post-traumatic IFI may be at greater risk of amputation, delays in wound healing, hospital complications, and death as compared to trauma patients who do not develop IFI. More research is needed to understand the factors surrounding the development and management of post-traumatic IFI to reduce the significant morbidity and mortality associated with this disease.
Ghabrial, Said A; Castón, José R; Jiang, Daohong; Nibert, Max L; Suzuki, Nobuhiro
Mycoviruses are widespread in all major taxa of fungi. They are transmitted intracellularly during cell division, sporogenesis, and/or cell-to-cell fusion (hyphal anastomosis), and thus their life cycles generally lack an extracellular phase. Their natural host ranges are limited to individuals within the same or closely related vegetative compatibility groups, although recent advances have established expanded experimental host ranges for some mycoviruses. Most known mycoviruses have dsRNA genomes packaged in isometric particles, but an increasing number of positive- or negative-strand ssRNA and ssDNA viruses have been isolated and characterized. Although many mycoviruses do not have marked effects on their hosts, those that reduce the virulence of their phytopathogenic fungal hosts are of considerable interest for development of novel biocontrol strategies. Mycoviruses that infect endophytic fungi and those that encode killer toxins are also of special interest. Structural analyses of mycoviruses have promoted better understanding of virus assembly, function, and evolution. Copyright © 2015 Elsevier Inc. All rights reserved.
Full Text Available Over the past decades, water pollution by trace organic compounds (ng/L has become one of the key environmental issues in developed countries. This is the case of the emerging contaminants called endocrine disrupting compounds (EDCs. EDCs are a new class of environmental pollutants able to mimic or antagonize the effects of endogenous hormones, and are recently drawing scientific and public attention. Their widespread presence in the environment solicits the need of their removal from the contaminated sites. One promising approach to face this challenge consists in the use of enzymatic systems able to react with these molecules. Among the possible enzymes, oxidative enzymes are attracting increasing attention because of their versatility, the possibility to produce them on large scale, and to modify their properties. In this study five different EDCs were treated with four different fungal laccases, also in the presence of both synthetic and natural mediators. Mediators significantly increased the efficiency of the enzymatic treatment, promoting the degradation of substrates recalcitrant to laccase oxidation. The laccase showing the best performances was chosen to further investigate its oxidative capabilities against micropollutant mixtures. Improvement of enzyme performances in nonylphenol degradation rate was achieved through immobilization on glass beads.
Pastor-Satorras, Romualdo; Vespignani, Alessandro
We study by analytical methods and large scale simulations a dynamical model for the spreading of epidemics in complex networks. In networks with exponentially bounded connectivity we recover the usual epidemic behavior with a threshold defining a critical point below that the infection prevalence is null. On the contrary, on a wide range of scale-free networks we observe the absence of an epidemic threshold and its associated critical behavior. This implies that scale-free networks are prone to the spreading and the persistence of infections whatever spreading rate the epidemic agents might possess. These results can help understanding computer virus epidemics and other spreading phenomena on communication and social networks
Zuo, Xiaoan; Wang, Shaokun; Lv, Peng; Zhou, Xin; Zhao, Xueyong; Zhang, Tonghui; Zhang, Jing
The trait-based approach shows that plant functional diversity strongly affects ecosystem properties. However, few empirical studies show the relationship between soil fungal diversity and plant functional diversity in natural ecosystems. We investigated soil fungal diversity along a restoration gradient of sandy grassland (mobile dune, semifixed dune, fixed dune, and grassland) in Horqin Sand Land, northern China, using the denaturing gradient gel electrophoresis of 18S rRNA and gene sequencing. We also examined associations of soil fungal diversity with plant functional diversity reflected by the dominant species' traits in community (community-weighted mean, CWM) and the dispersion of functional trait values (FD is). We further used the structure equation model (SEM) to evaluate how plant richness, biomass, functional diversity, and soil properties affect soil fungal diversity in sandy grassland restoration. Soil fungal richness in mobile dune and semifixed dune was markedly lower than those of fixed dune and grassland (P functional diversity explained nearly 70% variances of soil fungal richness. Strong association of soil fungal richness with the dominant species in the community supported the mass ratio hypothesis. Our results clearly highlight the role of plant functional diversity in enhancing associations of soil fungal diversity with community structure and soil properties in sandy grassland ecosystems.
Hong, Wei; Wen, Hai; Liao, Wanqing
To review the characteristics and evolution of the fungal spectrum, and the risk factors causing fungal infection, and to make progress in diagnosing fungal infection after organ transplantation. An English-language literature search (MEDLINE 1990 - 2000) and bibliographic review of textbooks and review articles. Twenty-three articles were selected from the literature that specifically addressed the stated purpose. Fungal infections in organ transplant patients were generally divided into two types: (1) disseminated primary or reactivation infection with one of the geographically restricted systemic mycoses; (2) opportunistic infection by fungal species that rarely cause invasive infection in normal hosts. The risk factors of fungal infection after a transplant can be evaluated and predicted according to the organ recipient's conditions before, during and after the transplant. Progress in early diagnostic methods during the past 10 years has mainly revolved around two aspects, culture and non-culture. It is important to undertake a systemic evaluation on the condition of the organ recipient before, during and after a transplant; should any risk factor for fungal infection be suspected, diagnosis should be made as early as possible by employing mycological techniques including culture and non-culture methods.
Yoshioka, Eiji; Hanley, Sharon J B; Kawanishi, Yasuyuki; Saijo, Yasuaki
The charcoal burning suicide epidemics in both Hong Kong and Taiwan have been well documented. However, little is known about the situation in Japan. To examine the impact of charcoal burning suicide on the overall and other method-specific suicide rates between 1998 and 2007 in Japan. Using data obtained from the Vital Statistics of Japan, negative binomial regression analyses were performed to investigate the impact of the charcoal burning method. In males and females aged 15-24 and 25-44 years, the charcoal burning epidemic led to a substantial increase in overall suicides, without a decrease in other methods. In all other age groups, no such trend was observed. In young Japanese, the charcoal burning method may have appealed to individuals who might not have chosen other highly or relatively lethal methods, and consequently led to an increase in overall suicides.
van der Feltz-Cornelis, Christina M
There has been much discussion in the media about the question of the existence of a depression epidemic. This leads on to the questions of whether the social and economic approaches are adequate, and what the alternatives are. The concept of the disease 'depression' can be defined using a medical model, or from a patient's or a societal perspective. From a medical perspective, indeed a depression epidemic has ensued from the increased prosperity and the associated decompression of the mortality rate. Society responded with preventative measures and policies aimed at improving functioning in the workplace. However, patients with a major depressive disorder (MDD) who are eligible for treatment are often not motivated to take it up, or are undertreated. Research is necessary in order to explore what patients think about the identification and treatment of depression. The confusion regarding the concept of depression found in the media, needs to be cleared.
Full Text Available Networks offer a fertile framework for studying the spread of infection in human and animal populations. However, owing to the inherent high-dimensionality of networks themselves, modelling transmission through networks is mathematically and computationally challenging. Even the simplest network epidemic models present unanswered questions. Attempts to improve the practical usefulness of network models by including realistic features of contact networks and of host–pathogen biology (e.g. waning immunity have made some progress, but robust analytical results remain scarce. A more general theory is needed to understand the impact of network structure on the dynamics and control of infection. Here we identify a set of challenges that provide scope for active research in the field of network epidemic models.
Zusman, Mara B.
Methamphetamine abuse has become an epidemic in the United States. As methamphetamine becomes increasingly available, more and more people are trying â€“ and becoming addicted to â€“ this potent drug. But although methamphetamine is made using over-the-counter (OTC) drugs containing pseudoephedrine, shifting OTC drugs containing pseudoephedrine to prescription status is not the solution to the methamphetamine crisis. Rather, society must adopt a comprehensive...
Cai Liming; Guo Shumin; Li, XueZhi; Ghosh, Mini
The paper investigates the global stability of a dengue epidemic model with saturation and bilinear incidence. The constant human recruitment rate and exponential natural death, as well as vector population with asymptotically constant population, are incorporated into the model. The model exhibits two equilibria, namely, the disease-free equilibrium and the endemic equilibrium. The stability of these two equilibria is controlled by the threshold number R 0 . It is shown that if R 0 is less than one, the disease-free equilibrium is globally asymptotically stable and in such a case the endemic equilibrium does not exist; if R 0 is greater than one, then the disease persists and the unique endemic equilibrium is globally asymptotically stable.
Full Text Available Fungi have been implicated as quantitatively the most important bioaerosol component of indoor air associated with contaminated air-conditioning systems. rarely, indoor fungi may cause human infections, but more commonly allergenic responses ranging from pneumonitis to asthma-like symptoms. From all air conditioner filters analyzed, 16 fungal taxa were isolated and identified. Aspergillus fumigatus causes more lethal infections worldwide than any other mold. Air-conditioning filters that adsorb moisture and volatile organics appear to provide suitable substrates for fungal colonization. It is important to stress that fungal colonization of air-conditioning systems should not be ignored, especially in hospital environments.
Dennis J. Baumgardner
Full Text Available Fungal infections in humans resulting from human or animal contact are relatively uncommon, but they include a significant proportion of dermatophyte infections. Some of the most commonly encountered diseases of the integument are dermatomycoses. Human or animal contact may be the source of all types of tinea infections, occasional candidal infections, and some other types of superficial or deep fungal infections. This narrative review focuses on the epidemiology, clinical features, diagnosis and treatment of anthropophilic dermatophyte infections primarily found in North America. Other human-acquired and zoonotic fungal infections also are discussed in brief.
Dhama, Kuldeep; Chakraborty, Sandip; Verma, Amit Kumar; Tiwari, Ruchi; Barathidasan, Rajamani; Kumar, Amit; Singh, Shambhu Dayal
Fungal/mycotic diseases cause significant economic losses to the poultry industry either due to their direct infectious nature or due to production of mycotoxins, the secondary fungal metabolites produced in grains or poultry feed. Several fungi have created havoc in the poultry industry and some of them cause direct harm to human health due to their zoonotic implications. They are responsible for high morbidity and mortality, especially in young birds and cause stunted growth and diarrhea; and fatal encephalitis. Mycotic dermatitis is a possible health hazard associated with poultry houses. Mycotoxins are the leading cause of producing immunosuppression in birds, which makes them prone to several bacterial and viral infections leading to huge economic losses to the poultry industry. In comparison to bacterial and viral diseases, advances in diagnosis, treatment, prevention and control of fungal diseases in poultry has not taken much attention. Recently, molecular biological tools have been explored for rapid and accurate diagnosis of important fungal infections. Effective prevention and control measures include: appropriate hygiene, sanitation and disinfection, strict biosecurity programme and regular surveillance/monitoring of fungal infections as well as following judicious use of anti-fungal drugs. Precautionary measures during crop production, harvesting and storing and in feed mixing plants can help to check the fungal infections including health hazards of mycotoxins/mycotoxicosis. The present review describes the fungal pathogens causing diseases in poultry/birds, especially focusing to their diagnosis, prevention and control measures, which would help in formulating appropriate strategies to have a check and control on these unwanted troubles to the poultry producers/farmers.
McGuire, Krista L; Fierer, Noah; Bateman, Carling; Treseder, Kathleen K; Turner, Benjamin L
Plant diversity is considered one factor structuring soil fungal communities because the diversity of compounds in leaf litter might determine the extent of resource heterogeneity for decomposer communities. Lowland tropical rain forests have the highest plant diversity per area of any biome. Since fungi are responsible for much of the decomposition occurring in forest soils, understanding the factors that structure fungi in tropical forests may provide valuable insight for predicting changes in global carbon and nitrogen fluxes. To test the role of plant diversity in shaping fungal community structure and function, soil (0-20 cm) and leaf litter (O horizons) were collected from six established 1-ha forest census plots across a natural plant diversity gradient on the Isthmus of Panama. We used 454 pyrosequencing and phospholipid fatty acid analysis to evaluate correlations between microbial community composition, precipitation, soil nutrients, and plant richness. In soil, the number of fungal taxa increased significantly with increasing mean annual precipitation, but not with plant richness. There were no correlations between fungal communities in leaf litter and plant diversity or precipitation, and fungal communities were found to be compositionally distinct between soil and leaf litter. To directly test for effects of plant species richness on fungal diversity and function, we experimentally re-created litter diversity gradients in litter bags with 1, 25, and 50 species of litter. After 6 months, we found a significant effect of litter diversity on decomposition rate between one and 25 species of leaf litter. However, fungal richness did not track plant species richness. Although studies in a broader range of sites is required, these results suggest that precipitation may be a more important factor than plant diversity or soil nutrient status in structuring tropical forest soil fungal communities.
Obesity and metabolic syndromes are major threats to health in both developed and developing countries. This opinion article is a holistic attempt to understand the obesity epidemic, by connecting it to the widespread narcissism in society. The narcissism epidemic refers to an increased prevalence of status-striving individualism and a decreased sense of community, observed in Westerns populations and spreading worldwide. Based on social personality and evolutionary psychology approaches, I speculate that this rise of narcissism underlies a steep social hierarchy resulting in increase of social stress. This social stress markedly affects individuals who are sensitive to social hierarchy dominance due to their personality, yet are relegated at a lower social position. I speculate that over-eating is one major mechanism for coping with this stress, and discuss the possibility that visceral fat may constitute an adaptive behaviour to the lower social hierarchy position, which is perceived as unjust. Connecting the prevalence of obesity to the narcissism epidemic allows for a more thorough examination of factors, which contribute to obesity, which includes early difficult childhood experience, lower rank, and the overall competitive framework of the society. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.
Full Text Available The transmission of infectious diseases can be affected by many or even hidden factors, making it difficult to accurately predict when and where outbreaks may emerge. One approach at the moment is to develop and deploy surveillance systems in an effort to detect outbreaks as timely as possible. This enables policy makers to modify and implement strategies for the control of the transmission. The accumulated surveillance data including temporal, spatial, clinical, and demographic information, can provide valuable information with which to infer the underlying epidemic networks. Such networks can be quite informative and insightful as they characterize how infectious diseases transmit from one location to another. The aim of this work is to develop a computational model that allows inferences to be made regarding epidemic network topology in heterogeneous populations. We apply our model on the surveillance data from the 2009 H1N1 pandemic in Hong Kong. The inferred epidemic network displays significant effect on the propagation of infectious diseases.
Fofana, Abdou Moutalab; Hurford, Amy
An overlooked aspect of disease ecology is considering how and why animals come into contact with one and other resulting in disease transmission. Mathematical models of disease spread frequently assume mass-action transmission, justified by stating that susceptible and infectious hosts mix readily, and foregoing any detailed description of host movement. Numerous recent studies have recorded, analysed and modelled animal movement. These movement models describe how animals move with respect to resources, conspecifics and previous movement directions and have been used to understand the conditions for the occurrence and the spread of infectious diseases when hosts perform a type of movement. Here, we summarize the effect of the different types of movement on the threshold conditions for disease spread. We identify gaps in the literature and suggest several promising directions for future research. The mechanistic inclusion of movement in epidemic models may be beneficial for the following two reasons. Firstly, the estimation of the transmission coefficient in an epidemic model is possible because animal movement data can be used to estimate the rate of contacts between conspecifics. Secondly, unsuccessful transmission events, where a susceptible host contacts an infectious host but does not become infected can be quantified. Following an outbreak, this enables disease ecologists to identify 'near misses' and to explore possible alternative epidemic outcomes given shifts in ecological or immunological parameters.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Author(s).
Ozel, Yasemin Kevser; Gedikli, Serap; Aytar, Pınar; Unal, Arzu; Yamaç, Mustafa; Cabuk, Ahmet; Kolankaya, Nazif
Cyanide, a hazardous substance, is released into the environment as a result of natural processes of various industrial activities which is a toxic pollutant according to Environmental Protection Agency. In nature, some microorganisms are responsible for the degradation of cyanide, but there is only limited information about the degradation characteristics of Basidiomycetes for cyanide. The aim of the present study is to determine cyanide degradation characteristics in some Basidiomycetes strains including Polyporus arcularius (T 438), Schizophyllum commune (T 701), Clavariadelphus truncatus (T 192), Pleurotus eryngii (M 102), Ganoderma applanatum (M 105), Trametes versicolor (D 22), Cerrena unicolor (D 30), Schizophyllum commune (D 35) and Ganoderma lucidum (D 33). The cyanide degradation activities of P. arcularius S. commune and G. lucidum were found to be more than that of the other fungi examined. The parameters including incubation time, amount of biomass, initial cyanide concentration, temperature, pH and agitation rate were optimized for the selected three potential fungal strains. The maximum cyanide degradation was obtained after 48 h of incubation at 30°C by P. arcularius (T 438). The optimum pH and agitation rate were measured as 10.5 and 150 rev/min, respectively. The amount of biomass was found as 3.0 g for the maximum cyanide biodegradation with an initial cyanide concentration of 100mg/L. In this study, agar was chosen entrapment agent for the immobilization of effective biomass. We suggested that P. arcularius (T 438) could be effective in the treatment of contaminated sites with cyanide due to capability of degrading cyanide. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
D. A. Khundzhua
Full Text Available The work is targeted to confirm participation of microscopic fungi in transformation of humus substances in aquatic environments. The research is focused on the spectroscopic study of the collection of fungal strains with different pigmentation of mycelium. Spectral properties of fungal metabolites were measured and compared to that of natural aquatic nonliving organic matter and commercial humus substances in aqueous solutions. The experiments revealed that the effect of microscopic fungi growing in the culture medium with added humate appeared as changes in the humic-type fluorescence: its characteristics became more similar to that of nonliving organic matter in natural waters than to original humate preparation. The experiments demonstrated degradation of coal-originated humate due to microbial activity into compounds of smaller molecular size and increased heterogeneity. We resume that transformation of humus substances by fungal cultures can be monitored and characterized using spectral measurements.
Rugbjerg, Peter; Naesby, Michael; Mortensen, Uffe Hasbro
BACKGROUND: Fungal polyketides include commercially important pharmaceuticals and food additives, e.g. the cholesterol-lowering statins and the red and orange monascus pigments. Presently, production relies on isolation of the compounds from the natural producers, and systems for heterologous...... production in easily fermentable and genetically engineerable organisms, such as Saccharomyces cerevisiae and Escherichia coli are desirable. Rubrofusarin is an orange polyketide pigment that is a common intermediate in many different fungal biosynthetic pathways. RESULTS: In this study, we established....... CONCLUSIONS: The reconstructed pathway for rubrofusarin in S. cerevisiae allows the production of a core scaffold molecule with a branch-point role in several fungal polyketide pathways, thus paving the way for production of further natural pigments and bioactive molecules. Furthermore, the reconstruction...
Saeedian, M.; Khalighi, M.; Azimi-Tafreshi, N.; Jafari, G. R.; Ausloos, M.
Memory has a great impact on the evolution of every process related to human societies. Among them, the evolution of an epidemic is directly related to the individuals' experiences. Indeed, any real epidemic process is clearly sustained by a non-Markovian dynamics: memory effects play an essential role in the spreading of diseases. Including memory effects in the susceptible-infected-recovered (SIR) epidemic model seems very appropriate for such an investigation. Thus, the memory prone SIR model dynamics is investigated using fractional derivatives. The decay of long-range memory, taken as a power-law function, is directly controlled by the order of the fractional derivatives in the corresponding nonlinear fractional differential evolution equations. Here we assume "fully mixed" approximation and show that the epidemic threshold is shifted to higher values than those for the memoryless system, depending on this memory "length" decay exponent. We also consider the SIR model on structured networks and study the effect of topology on threshold points in a non-Markovian dynamics. Furthermore, the lack of access to the precise information about the initial conditions or the past events plays a very relevant role in the correct estimation or prediction of the epidemic evolution. Such a "constraint" is analyzed and discussed.
Fungal endophytes of the obligate parasitic dwarf mistletoe Arceuthobium americanum (Santalaceae) act antagonistically in vitro against the native fungal pathogen Cladosporium (Davidiellaceae) of their host.
Martin, Lyssa L; Ross Friedman, Cynthia M; Phillips, Lori A
Endophytic fungi likely occur in all plants, yet little is known about those of parasitic plants, despite their potential to influence parasite success. Arceuthobium americanum is a parasitic angiosperm that greatly compromises the North American timber industry. We hypothesized that (1) A. americanum hosts fungal endophytes, and (2) these endophytes help A. americanum resist infection by fungal pathogens. • Healthy A. americanum stem and fruit tissues were differentially stained for cellulose and chitin and visualized using fluorescence microscopy. Stem sections (sterilized vs. unsterilized) and seeds were incubated on agar plates to cultivate fungi, both to extract DNA for ITS rDNA sequencing and to observe interactions with native fungi from unsterilized specimens. • Aside from xylem vessel elements, fungal structures were observed in all tissues, including those of the embryo. The ITS sequences of fungi cultured from internal tissues closely matched those of the known endophytes Phoma, Sydowia, and Phacidiopycnis, while those of surface organisms closely matched Cladosporium spp. Cultured fungi from internal tissues (putative endophytes) inhibited the growth of the surface organisms without affecting the other endophytes. • Fungal communities are established in A. americanum stems as well as in fruits and seeds, suggesting vertical transmission. These internally derived fungi act antagonistically toward fungi with pathogenic tendencies. As such, native mistletoe endophytes might protect A. americanum against fungal pathogens in nature. In the future, manipulation of endophytes might be a component of mistletoe control programs.
Baker, Scott E.; Bruno, Kenneth S.; Butcher, Mark G.; Collett, James R.; Culley, David E.; Dai, Ziyu; Magnuson, Jon K.; Panisko, Ellen A.
In 2009, we continued to address barriers to fungal fermentation in the primary areas of morphology control, genomics, proteomics, fungal hyperproductivity, biomass-to-products via fungal based consolidated bioprocesses, and filamentous fungal ethanol. “Alternative renewable fuels from fungi” was added as a new subtask. Plans were also made to launch a new advanced strain development subtask in FY2010.
Aly, A H; Debbab, A; Proksch, P
The potential of endophytic fungi as promising sources of bioactive natural products continues to attract broad attention. Endophytic fungi are defined as fungi that live asymptomatically within the tissues of higher plants. This overview will highlight the uniqueness of endophytic fungi as alternative sources of pharmaceutically valuable compounds originally isolated from higher plants, e.g. paclitaxel, camptothecin and podophyllotoxin. In addition, it will shed light on the fungal biosynthesis of plant associated metabolites as well as new approaches developed to improve the production of commercially important plant derived compounds with the involvement of endophytic fungi.
Busk, Peter Kamp; Lange, Lene
Elucidation of fungal biomass degradation is important for understanding the turnover of biological materials in nature and has important implications for industrial biomass conversion. In recent years there has been an increasing interest in elucidating the biological role of thermophilic fungi....... Thermophilic fungi are the only described eukaryotes that can grow at temperatures above 45 ºC. All 16 fungi were able to grow on crystalline cellulose but their secreted enzymes showed widely different cellulolytic activities, pH optima and thermostabilities. Interestingly, in contrast to previous reports, we...
Scarlat, Iuliana; Haiducu, Maria; Stepa, Raluca
The aim of the studies was to determine the level and kind of fungal contamination of air in museum, deposits patrimony, restoration and conservation laboratories and their effects on health of workers. Microbiological air purity was measured with a SAS-100 Surface Air System impactor. The fungal contamination was observed in all 54 rooms where we made determinations. The highest levels of fungal were recorded at rooms with hygroscopic patrimony objects, eg carpets, chairs, upholstered chairs, books etc. The most species identified included under common allergens: Aspergillus, Penicillium, and Mucor. There fungal species belonging to the genus identified in this study, can trigger serious diseases museum workers, such as for example Aspergillus fumigatus, known allergies and toxic effects that may occur. In some places of the museum, occupational exposure limit values to fungi present in the air in the work environment, recommended by the specialized literature, have been overcome.
Nielsen, Esben; Heegaard, S; Prause, J U
Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM) images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological...... analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience...... with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12...
Haugwitz, Merian Skouw
and nutrient availability and storage. By combining molecular methods such as 454 pyrosequencing and quantitative PCR of fungal ITS amplicons with analyses of soil enzymes, nutrient pools of carbon, nitrogen and phosphorus we were able to characterize soil fungal communities as well as their impact on nutrient...... storage in both a shorter and longer term global change experiment. Extended drought at the dry, temperate heath showed that soil fungi were well adapted to dry conditions. Furthermore, soil fungal communities responded significantly to seasonal fluctuations at the temperate heath, but despite large......Global change will affect the functioning and structure of terrestrial ecosystems and since soil fungi are key players in organic matter decomposition and nutrient turnover, shifts in fungal community composition might have a strong impact on soil functioning. The main focus of this thesis...
... includes places like chicken coops and caves. Wear gloves when handling materials such as soil, moss, or ... Cell Transplant Recipients. MMWR 2000;49:1-128. Top of Page Related Links Fungal Meningitis National Center ...
Nazeri, M.; Hashemi, S.J.; Ardehali, M.; Rezaei, S.; Seyedmousavi, S.; Zareei, M.; Hosseinjani, E.
BACKGROUND: Fungal rhino sinusitis (FRS) is an important infection of para nasal sinuses, which encompasses two main categories; invasive and noninvasive forms according to histopathological findings. Aspergillus spp are the most common species isolated from noninvasive form, while Mucorales are
An impressively large proportion of fungicides applied in European, North American and Australian agriculture has been used to manage grapevine powdery mildew (Erysiphe necator), grapevine downy mildew (Plasmopara viticola), and botrytis bunch rot (Botrytis cinerea). These fungal and oomycetous plan...
microscopy and immunocytochemical labelling of β-1,4-N- acetyl-D-glucosamine residues of chitin walls, a fungal signature confirmed its presence (Maldonado et al., 2005). Interestingly these yeasts are reported to be maternally transmitted from the soma...
laboratory media. In such instances, a detailed and careful examination of the disease symptoms and the endobiotic fungal parasites is to be recorded. Maintaining dual culture of the healthy and infected host also helps to fulfill these postulates partially....
Loeffler, Juergen; Hebart, Holger; Bialek, Ralf; Hagmeyer, Lars; Schmidt, Diethard; Serey, Francois-Prâseth; Hartmann, Matthias; Eucker, Jan; Einsele, Hermann
Successful in vitro amplification of fungal DNA in clinical specimens has been reported recently. In a collaboration among five European centers, the frequency and risk of contamination due to airborne spore inoculation or carryover contamination in fungal PCR were analyzed. The identities of all contaminants were specified by cycle sequencing and GenBank analysis. Twelve of 150 PCR assays that together included over 2,800 samples were found to be contaminated (3.3% of the negative controls were contaminated during the DNA extraction, and 4.7% of the PCR mixtures were contaminated during the amplification process). Contaminants were specified as Aspergillus fumigatus, Saccharomyces cerevisiae, and Acremonium spp. Further analysis showed that commercially available products like zymolyase powder or 10× PCR buffer may contain fungal DNA. In conclusion, the risk of contamination is not higher in fungal PCR assays than in other diagnostic PCR-based assays if general precautions are taken. PMID:10074553
Bartoli, Claudia; Lamichhane, Jay Ram; Berge, Odile; Guilbaud, Caroline; Varvaro, Leonardo; Balestra, Giorgio M; Vinatzer, Boris A; Morris, Cindy E
New economically important diseases on crops and forest trees emerge recurrently. An understanding of where new pathogenic lines come from and how they evolve is fundamental for the deployment of accurate surveillance methods. We used kiwifruit bacterial canker as a model to assess the importance of potential reservoirs of new pathogenic lineages. The current kiwifruit canker epidemic is at least the fourth outbreak of the disease on kiwifruit caused by Pseudomonas syringae in the mere 50 years in which this crop has been cultivated worldwide, with each outbreak being caused by different genetic lines of the bacterium. Here, we ask whether strains in natural (non-agricultural) environments could cause future epidemics of canker on kiwifruit. To answer this question, we evaluated the pathogenicity, endophytic colonization capacity and competitiveness on kiwifruit of P. syringae strains genetically similar to epidemic strains and originally isolated from aquatic and subalpine habitats. All environmental strains possessing an operon involved in the degradation of aromatic compounds via the catechol pathway grew endophytically and caused symptoms in kiwifruit vascular tissue. Environmental and epidemic strains showed a wide host range, revealing their potential as future pathogens of a variety of hosts. Environmental strains co-existed endophytically with CFBP 7286, an epidemic strain, and shared about 20 virulence genes, but were missing six virulence genes found in all epidemic strains. By identifying the specific gene content in genetic backgrounds similar to known epidemic strains, we developed criteria to assess the epidemic potential and to survey for such strains as a means of forecasting and managing disease emergence. © 2014 BSPP AND JOHN WILEY & SONS LTD.
Mikosz, Christina A.; Smith, Rachel M.; Kim, Moon; Tyson, Clara; Lee, Ellen H.; Adams, Eleanor; Straif-Bourgeois, Susanne; Sowadsky, Rick; Arroyo, Shannon; Grant-Greene, Yoran; Duran, Julie; Vasquez, Yvonne; Robinson, Byron F.; Harris, Julie R.; Lockhart, Shawn R.
Fungal endophthalmitis is a rare but serious infection. In March 2012, several cases of probable and laboratory-confirmed fungal endophthalmitis occurring after invasive ocular procedures were reported nationwide. We identified 47 cases in 9 states: 21 patients had been exposed to the intraocular dye Brilliant Blue G (BBG) during retinal surgery, and the other 26 had received an intravitreal injection containing triamcinolone acetonide. Both drugs were produced by Franck’s Compounding Lab (Oc...
Gérald E. Piérard; Sébastien L. Piérard
Background: Thigmotropism is a biologic feature coping with the directional growth of cells following topographical guidance cues. This mechanism is involved in the invasive phase of pathogen and opportunistic fungi. It was shown experimentally with fungal hyphae of both dermatophytes and nondermatophyte molds, as well as with the mycelial phase of the dimorphic yeast Candida albicans. Objective: To revisit histomycology in onychomycoses of a diversity of fungal origins. Method: Histopatholog...
Baisakhi Bakat; Subhendu Chowdhury; Amitabha Roy Chowdhury; Soumitra Ghosh; Barin Kumar Roychaudhuri
Abstract Objective : To evaluate the treatment outcomes of multimodality therapy for allergic fungal rhinosinusitis. Study Design: Prospective Observational Study. Materials&methods : This study was carried out in the department of ENT & Head neck Surgery, Vivekananda Institute of Medical Sciences, Ramakrishna Mission Seva Pratishthan, Kolkata from January 2010 to July 2011. During this study period of one & half years, 20 subjects having Allergic Fungal Sinusitis were selected fr...
Bertuzzo, E.; Mari, L.; Righetto, L.; Casagrandi, R.; Gatto, M.; Rodriguez-Iturbe, I.; Rinaldo, A.
As a major cholera epidemic progresses in Haiti, and the figures of the infection, up to December 2011, climb to 522,000 cases and 7,000 deaths, the development of general models to track and predict the evolution of the outbreak, so as to guide the allocation of medical supplies and staff, is gaining notable urgency. We propose here a spatially explicit epidemic model that accounts for the dynamics of susceptible and infected individuals as well as the redistribution of Vibrio cholera, the causative agent of the disease, among different human communities. In particular, we model two spreading pathways: the advection of pathogens through hydrologic connections and the dissemination due to human mobility described by means of a gravity-like model. To this end the country has been divided into hydrologic units based on drainage directions derived from a digital terrain model. Moreover the population of each unit has been estimated from census data downscaled to 1 km x 1 km resolution via remotely sensed geomorphological information (LandScan project). The model directly accounts for the role of rainfall patterns in driving the seasonality of cholera outbreaks. The two main outbreaks in fact occurred during the rainy seasons (October and May) when extensive floodings severely worsened the sanitation conditions and, in turn, raised the risk of infection. The model capability to reproduce the spatiotemporal features of the epidemic up to date grants robustness to the foreseen future development. To this end, we generate realistic scenario of future precipitation in order to forecast possible epidemic paths up to the end of the 2013. In this context, the duration of acquired immunity, a hotly debated topic in the scientific community, emerges as a controlling factor for progression of the epidemic in the near future. The framework presented here can straightforwardly be used to evaluate the effectiveness of alternative intervention strategies like mass vaccinations
McKelvie William R
Full Text Available Abstract Background A lack of consensus on how to define malaria epidemics has impeded the evaluation of early detection systems. This study aimed to develop local definitions of malaria epidemics in a known malarious area of Iran, and to use that definition to evaluate the validity of several epidemic alert thresholds. Methods Epidemic definition variables generated from surveillance data were plotted against weekly malaria counts to assess which most accurately labelled aberrations. Various alert thresholds were then generated from weekly counts or log counts. Finally, the best epidemic definition was used to calculate and compare sensitivities, specificities, detection delays, and areas under ROC curves of the alert thresholds. Results The best epidemic definition used a minimum duration of four weeks and week-specific and overall smoothed geometric means plus 1.0 standard deviation. It defined 13 epidemics. A modified C-SUM alert of untransformed weekly counts using a threshold of mean + 0.25 SD had the highest combined sensitivity and specificity. Untransformed C-SUM alerts also had the highest area under the ROC curve. Conclusions Defining local malaria epidemics using objective criteria facilitated the evaluation of alert thresholds. This approach needs further study to refine epidemic definitions and prospectively evaluate epidemic alerts.
McKelvie, William R; Haghdoost, Ali Akbar; Raeisi, Ahmad
A lack of consensus on how to define malaria epidemics has impeded the evaluation of early detection systems. This study aimed to develop local definitions of malaria epidemics in a known malarious area of Iran, and to use that definition to evaluate the validity of several epidemic alert thresholds. Epidemic definition variables generated from surveillance data were plotted against weekly malaria counts to assess which most accurately labelled aberrations. Various alert thresholds were then generated from weekly counts or log counts. Finally, the best epidemic definition was used to calculate and compare sensitivities, specificities, detection delays, and areas under ROC curves of the alert thresholds. The best epidemic definition used a minimum duration of four weeks and week-specific and overall smoothed geometric means plus 1.0 standard deviation. It defined 13 epidemics. A modified C-SUM alert of untransformed weekly counts using a threshold of mean+0.25 SD had the highest combined sensitivity and specificity. Untransformed C-SUM alerts also had the highest area under the ROC curve. Defining local malaria epidemics using objective criteria facilitated the evaluation of alert thresholds. This approach needs further study to refine epidemic definitions and prospectively evaluate epidemic alerts.
Badiane, Aida S; Ndiaye, Daouda; Denning, David W
Senegal has a high rate of tuberculosis and a low HIV seropositivity rate and aspergilloma, life-threatening fungal infections, dermatophytosis and mycetoma have been reported in this study. All published epidemiology papers reporting fungal infection rates from Senegal were identified. Where no data existed, we used specific populations at risk and fungal infection frequencies in each to estimate national incidence or prevalence. The results show that tinea capitis is common being found in 25% of children, ~1.5 million. About 191,000 Senegalese women get recurrent vaginal thrush, ≥4 times annually. We estimate 685 incident cases of chronic pulmonary aspergillosis (CPA) following TB and prevalence of 2160 cases. Asthma prevalence in adults varies from 3.2% to 8.2% (mean 5%); 9976 adults have allergic bronchopulmonary aspergillosis (ABPA) and 13,168 have severe asthma with fungal sensitisation (SAFS). Of the 59,000 estimated HIV-positive patients, 366 develop cryptococcal meningitis; 1149 develop Pneumocystis pneumonia and 1946 develop oesophageal candidiasis, in which oral candidiasis (53%) and dermatophytosis (16%) are common. Since 2008-2010, 113 cases of mycetoma were diagnosed. In conclusion, we estimate that 1,743,507 (12.5%) people in Senegal suffer from a fungal infection, excluding oral candidiasis, fungal keratitis, invasive candidiasis or aspergillosis. Diagnostic and treatment deficiencies should be rectified to allow epidemiological studies. © 2015 Blackwell Verlag GmbH.
Nielsen, E; Heegaard, S; Prause, J U; Ivarsen, A; Mortensen, K L; Hjortdal, J
Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM) images in filamentous fungal keratitis. Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12-69), 6 out of 17 (35%) cultures were positive and a total of 6/7 (86%) IVCM scans were positive. Three different categories of IVCM results for the grading of diagnostic certainty were formed. IVCM is a valuable tool for diagnosing filamentous fungal keratitis. In order to improve the reliability of IVCM, we suggest implementing a simple and clinically applicable grading system for aiding the interpretation of IVCM images of filamentous fungal keratitis.
Full Text Available Purpose: Introducing a simple image grading system to support the interpretation of in vivo confocal microscopy (IVCM images in filamentous fungal keratitis. Setting: Clinical and confocal studies took place at the Department of Ophthalmology, Aarhus University Hospital, Denmark. Histopathological analysis was performed at the Eye Pathology Institute, Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark. Methods: A recent series of consecutive patients with filamentous fungal keratitis is presented to demonstrate the results from in-house IVCM. Based upon our experience with IVCM and previously published images, we composed a grading system for interpreting IVCM images of filamentous fungal keratitis. Results: A recent case series of filamentous fungal keratitis from 2011 to 2012 was examined. There were 3 male and 3 female patients. Mean age was 44.5 years (range 12-69, 6 out of 17 (35% cultures were positive and a total of 6/7 (86% IVCM scans were positive. Three different categories of IVCM results for the grading of diagnostic certainty were formed. Conclusion: IVCM is a valuable tool for diagnosing filamentous fungal keratitis. In order to improve the reliability of IVCM, we suggest implementing a simple and clinically applicable grading system for aiding the interpretation of IVCM images of filamentous fungal keratitis.
Full Text Available Ceramide monohexosides (CMHs, cerebrosides are glycosphingolipids composed of a hydrophobic ceramide linked to one sugar unit. In fungal cells, CMHs are very conserved molecules consisting of a ceramide moiety containing 9-methyl-4,8-sphingadienine in amidic linkage to 2-hydroxyoctadecanoic or 2-hydroxyhexadecanoic acids, and a carbohydrate portion consisting of one residue of glucose or galactose. 9-Methyl 4,8-sphingadienine-containing ceramides are usually glycosylated to form fungal cerebrosides, but the recent description of a ceramide dihexoside (CDH presenting phytosphingosine in Magnaporthe grisea suggests the existence of alternative pathways of ceramide glycosylation in fungal cells. Along with their unique structural characteristics, fungal CMHs have a peculiar subcellular distribution and striking biological properties. In Pseudallescheria boydii, Candida albicans, Cryptococcus neoformans, Aspergillus nidulans, A. fumigatus, and Schizophyllum commune, CMHs are apparently involved in morphological transitions and fungal growth. The elucidation of structural and functional aspects of fungal cerebrosides may therefore contribute to the design of new antifungal agents inhibiting growth and differentiation of pathogenic species.
Vrije, de T.; Antoine, N.; Buitelaar, R.M.; Oostra, J.; Rinzema, A.; Weber, F.J.
Biological control agents (BCAs) are potential alternatives for the chemical fungicides presently used in agriculture to fight plant diseases. Coniothyrium minitans is an example of a promising fungal BCA. It is a naturally occurring parasite of the fungus Sclerotinia sclerotiorum, a wide-spread
Jennifer A. Rudgers; Rebecca A. Fletcher; Eric Olivas; Carolyn A. Young; Nikki D. Charlton; Dean E. Pearson; John L. Maron
When symbionts are inherited by offspring, they can have substantial ecological and evolutionary consequences because they occur in all host life stages. Although natural frequencies of inherited symbionts are commonly <100 %, few studies investigate the ecological drivers of variation in symbiont prevalence. In plants, inherited fungal endophytes can...
Dayu, Wu; Yanping, Zhao; Muhua, Zheng; Jie, Zhou; Zonghua, Liu
Epidemic spreading has been studied for a long time and is currently focused on the spreading of multiple pathogens, especially in multiplex networks. However, little attention has been paid to the case where the mutual influence between different pathogens comes from a fraction of epidemic propagators, such as bisexual people in two separated groups of heterosexual and homosexual people. We here study this topic by presenting a network model of two layers connected by impulsive links, in contrast to the persistent links in each layer. We let each layer have a distinct pathogen and their interactive infection is implemented by a fraction of propagators jumping between the corresponding pairs of nodes in the two layers. By this model we show that (i) the propagators take the key role to transmit pathogens from one layer to the other, which significantly influences the stabilized epidemics; (ii) the epidemic thresholds will be changed by the propagators; and (iii) a reverse-feeding effect can be expected when the infective rate is smaller than its threshold of isolated spreading. A theoretical analysis is presented to explain the numerical results. Project supported by the National Natural Science Foundation of China (Grant Nos. 11135001, 11375066, and 11405059) and the National Basic Key Program of China (Grant No. 2013CB834100).
Tian, H.; Yan, Ch.; Xu, L.; Büntgen, Ulf; Stenseth, N. C.; Zhang, Z.
Roč. 114, č. 49 (2017), s. 12970-12975 ISSN 0027-8424 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:86652079 Keywords : infectious-diseases * northern-hemisphere * cholera dynamics * time-series * 2 millennia * reconstruction * variability * management * plague * ad * epidemics * climate * scale dependent * natural disaster * disease Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 9.661, year: 2016
Pramod Kumar; Jayprakash Yadav; Meenu Jain; Preeti Yadav; A.K. Goel; Pramod Kumar Yadava
In recent years, emerging trend of antibiotic resistance in Vibrio cholerae associated with cholera epidemics is a matter of serious concern for the management of the disease. Indiscriminate use of antibiotics generally results in selection of antibiotic resistant strains. Introduction of newer antibiotics is a challenging task for the researchers as bacteria soon attain resistance. Therefore, identifying natural compounds of medicinal importance for control of cholera would be the best alter...
Granell, Clara; Gómez, Sergio; Arenas, Alex
We present the analysis of the interrelation between two processes accounting for the spreading of an epidemic, and the information awareness to prevent its infection, on top of multiplex networks. This scenario is representative of an epidemic process spreading on a network of persistent real contacts, and a cyclic information awareness process diffusing in the network of virtual social contacts between the same individuals. The topology corresponds to a multiplex network where two diffusive processes are interacting affecting each other. The analysis using a microscopic Markov chain approach reveals the phase diagram of the incidence of the epidemics and allows us to capture the evolution of the epidemic threshold depending on the topological structure of the multiplex and the interrelation with the awareness process. Interestingly, the critical point for the onset of the epidemics has a critical value (metacritical point) defined by the awareness dynamics and the topology of the virtual network, from which the onset increases and the epidemics incidence decreases.
Roberts, Mick G; Andreasen, Viggo; Lloyd, Alun
Deterministic models have a long history of being applied to the study of infectious disease epidemiology. We highlight and discuss nine challenges in this area. The first two concern the endemic equilibrium and its stability. We indicate the need for models that describe multi-strain infections......, infections with time-varying infectivity, and those where superinfection is possible. We then consider the need for advances in spatial epidemic models, and draw attention to the lack of models that explore the relationship between communicable and non-communicable diseases. The final two challenges concern...
Gomes, Sofia I F; Merckx, Vincent S F T; Saavedra, Serguei
The vast majority of plants obtain an important proportion of vital resources from soil through mycorrhizal fungi. Generally, this happens in exchange of photosynthetically fixed carbon, but occasionally the interaction is mycoheterotrophic, and plants obtain carbon from mycorrhizal fungi. This process results in an antagonistic interaction between mycoheterotrophic plants and their fungal hosts. Importantly, the fungal-host diversity available for plants is restricted as mycoheterotrophic interactions often involve narrow lineages of fungal hosts. Unfortunately, little is known whether fungal-host diversity may be additionally modulated by plant-plant interactions through shared hosts. Yet, this may have important implications for plant competition and coexistence. Here, we use DNA sequencing data to investigate the interaction patterns between mycoheterotrophic plants and arbuscular mycorrhizal fungi. We find no phylogenetic signal on the number of fungal hosts nor on the fungal hosts shared among mycoheterotrophic plants. However, we observe a potential trend toward increased phylogenetic diversity of fungal hosts among mycoheterotrophic plants with increasing overlap in their fungal hosts. While these patterns remain for groups of plants regardless of location, we do find higher levels of overlap and diversity among plants from the same location. These findings suggest that species coexistence cannot be fully understood without attention to the two sides of ecological interactions.
He, Dan; Hao, Jilong; Gao, Song; Wan, Xue; Wang, Wanting; Shan, Qiushi; Wang, Li
Fungal keratitis is a worldwide-distributed refractory and potentially blinding ocular infection caused by various fungi. It is necessary to investigate the etiological and epidemiological characteristics of this disease and establish a rapid and specific pathogenic identification method. Here, we isolated and identified fungal pathogens of 275 patients with presumed fungal keratitis from Jilin Province, China, and conducted statistical analyses of epidemiological information. The positive rate of fungal culture was 72.0 %. Fusarium sp. was the most common genus among 210 fungal isolates. The predominant species were Fusarium solani, Aspergillus fumigatus, and Candida glabrata, which accounted for over 50 % of the isolated organisms. Corneal trauma and previous use of drugs were the most important predisposing factors. In addition, a multiplex polymerase chain reaction (PCR) was designed with species-specific primers of the three species that could identify them with amplicons of approximately 330 bp from F. solani, 275 bp from A. fumigatus, and 230 bp from C. glabrata. Additionally, PCR with fungal universal primers and multiplex PCR were performed using DNA prepared by an improved DNA extraction method from corneal scrapings. With this method, fungal pathogens from corneal scrapings could be specifically and rapidly identified within 8 h. The culture-independent rapid identification of corneal scrapings may have great significance for the early diagnosis and treatment of fungal keratitis.
Rozanova, Liudmila; Alekseev, Vadim; Temerev, Alexander
that amount of data transferred between network nodes possesses a Pareto distribution, implying scale-free properties. In this context, more heterogeneity in susceptibility means the less severe epidemic progression, and, on the contrary, more heterogeneity in infectivity leads to more severe epidemics...... — assuming that the other parameter (either heterogeneity or susceptibility) stays fixed. The results are general enough to be useful for estimating the epidemic progression with no significant acquired immunity — in the cases where Pareto distribution holds....
de Vrije, T; Antoine, N; Buitelaar, R M; Bruckner, S; Dissevelt, M; Durand, A; Gerlagh, M; Jones, E E; Lüth, P; Oostra, J; Ravensberg, W J; Renaud, R; Rinzema, A; Weber, F J; Whipps, J M
Biological control agents (BCAs) are potential alternatives for the chemical fungicides presently used in agriculture to fight plant diseases. Coniothyrium minitans is an example of a promising fungal BCA. It is a naturally occurring parasite of the fungus Sclerotinia sclerotiorum, a wide-spread pathogen which substantially reduces the yield of many crops. This review describes, exemplified by C. minitans, the studies that need to be carried out before a fungal BCA is successfully introduced into the market. The main aspects considered are the biology of C. minitans, the development of a product by mass production of spores using solid-state fermentation technology, its biocontrol activity and marketing of the final product.
Sun, Mengfeng; Lou, Yijun; Duan, Jinqiao; Fu, Xinchu
During the spread of an epidemic, individuals in realistic networks may exhibit collective behaviors. In order to characterize this kind of phenomenon and explore the correlation between collective behaviors and epidemic spread, in this paper, we construct several mathematical models (including without delay, with a coupling delay, and with double delays) of epidemic synchronization by applying the adaptive feedback motivated by real observations. By using Lyapunov function methods, we obtain the conditions for local and global stability of these epidemic synchronization models. Then, we illustrate that quenched mean-field theory is more accurate than heterogeneous mean-field theory in the prediction of epidemic synchronization. Finally, some numerical simulations are performed to complement our theoretical results, which also reveal some unexpected phenomena, for example, the coupling delay and epidemic delay influence the speed of epidemic synchronization. This work makes further exploration on the relationship between epidemic dynamics and synchronization dynamics, in the hope of being helpful to the study of other dynamical phenomena in the process of epidemic spread.
Hippocrates gave the term 'epidemic' its medical meaning. From antiquity to modern times, the meaning of the word epidemic has continued to evolve. Over the centuries, researchers have reached an understanding of the varying aspects of epidemics and have tried to combat them. The role played by travel, trade, and human exchanges in the propagation of epidemic infectious diseases has been understood. In 1948, the World Health Organization was created and given the task of advancing ways of combating epidemics. An early warning system to combat epidemics has been implemented by the WHO. The Global Outbreak Alert and Response Network (GOARN) is collaboration between existing institutions and networks that pool their human and technical resources to fight outbreaks. Avian influenza constitutes currently the most deadly epidemic threat, with fears that it could rapidly reach pandemic proportions and put several thousands of lives in jeopardy. Thanks to the WHO's support, most of the world's countries have mobilised and implemented an 'Action Plan for Pandemic Influenza'. As a result, most outbreaks of the H5N1 avian flu virus have so far been speedily contained. Cases of dengue virus introduction in countries possessing every circumstance required for its epidemic spread provide another example pertinent to the prevention of epidemics caused by vector-borne pathogens.
Martial L Ndeffo Mbah
Full Text Available Deployment of limited resources is an issue of major importance for decision-making in crisis events. This is especially true for large-scale outbreaks of infectious diseases. Little is known when it comes to identifying the most efficient way of deploying scarce resources for control when disease outbreaks occur in different but interconnected regions. The policy maker is frequently faced with the challenge of optimizing efficiency (e.g. minimizing the burden of infection while accounting for social equity (e.g. equal opportunity for infected individuals to access treatment. For a large range of diseases described by a simple SIRS model, we consider strategies that should be used to minimize the discounted number of infected individuals during the course of an epidemic. We show that when faced with the dilemma of choosing between socially equitable and purely efficient strategies, the choice of the control strategy should be informed by key measurable epidemiological factors such as the basic reproductive number and the efficiency of the treatment measure. Our model provides new insights for policy makers in the optimal deployment of limited resources for control in the event of epidemic outbreaks at the landscape scale.
Full Text Available Li-Tzy Wu,1–4 Udi E Ghitza,5 Anne L Burns,6 Paolo Mannelli,1 1Department of Psychiatry and Behavioral Sciences, 2Department of Medicine, 3Duke Clinical Research Institute, Duke University School of Medicine, 4Center for Child and Family Policy, Sanford School of Public Policy, Duke University, Durham, NC, 5Center for Clinical Trials Network, National Institute on Drug Abuse, Bethesda, MD, 6American Pharmacists Association, Washington, DC, USA The USA is experiencing an opioid overdose epidemic. It has been driven largely by prescription opioids and intensified by a surge of illicit opioids (e.g., heroin and fentanyl.1,2 Drug-involved overdose, mainly opioids (e.g., prescription opioids and heroin, is a leading cause of accidental death in the USA. The opioid overdose epidemic has been escalating consistently for over a decade.2 Every day, an estimated 91 Americans die from opioid-related overdose.3 Opioid overdose appears to have disproportionally affected men, adults aged 25–64 years, and non-Hispanic whites.2
Kotsiou, Antonia; Michalaki, Vasiliki; Anagnostopoulou, Helen N
In the recent Greek ages the most devastating epidemics were plague, smallpox, leprosy and cholera. In 1816 plague struck the Ionian and Aegean Islands, mainland Greece, Constantinople and Smyrna. The Venetians ruling the Ionian Islands effectively combated plague in contrast to the Ottomans ruling all other regions. In 1922, plague appeared in Patras refugees who were expelled by the Turks from Smyrna and Asia Minor. Inoculation against smallpox was first performed in Thessaly by the Greek women, and the Greek doctors Emmanouel Timonis (1713, Oxford) and Jakovos Pylarinos (1715, Venice) made relevant scientific publications. The first leper colony opened in Chios Island. In Crete, Spinalonga was transformed into a leper island, which following the Independence War against Turkish occupation and the unification of Crete with Greece in 1913, was classified as an International Leper Hospital. Cholera struck Greece in 1853-1854 brought by the French troops during the Crimean War, and again during the Balkan Wars (1912-13) when the Bulgarian troops brought cholera to northern Greece. Due to successive wars, medical assistance was not always available, so desperate people turned many times to religion through processions in honor of local saints, for their salvation in epidemics.
Clark, David J; Schumacher, Mark A
America is in the midst of an opioid epidemic characterized by aggressive prescribing practices, highly prevalent opioid misuse, and rising rates of prescription and illicit opioid overdose-related deaths. Medical and lay public sentiment have become more cautious with respect to prescription opioid use in the past few years, but a comprehensive strategy to reduce our reliance on prescription opioids is lacking. Addressing this epidemic through reductions in unnecessary access to these drugs while implementing measures to reduce demand will be important components of any comprehensive solution. Key supply-side measures include avoiding overprescribing, reducing diversion, and discouraging misuse through changes in drug formulations. Important demand-side measures center around educating patients and clinicians regarding the pitfalls of opioid overuse and methods to avoid unnecessary exposure to these drugs. Anesthesiologists, by virtue of their expertise in the use of these drugs and their position in guiding opioid use around the time of surgery, have important roles to play in reducing patient exposure to opioids and providing education about appropriate use. Aside from the many immediate steps that can be taken, clinical and basic research directed at understanding the interaction between pain and opioid misuse is critical to identifying the optimal use of these powerful pain relievers in clinical practice.
Frerichs, R R; Keim, P S; Barrais, R; Piarroux, R
Cholera appeared in Haiti in October 2010 for the first time in recorded history. The causative agent was quickly identified by the Haitian National Public Health Laboratory and the United States Centers for Disease Control and Prevention as Vibrio cholerae serogroup O1, serotype Ogawa, biotype El Tor. Since then, >500 000 government-acknowledged cholera cases and >7000 deaths have occurred, the largest cholera epidemic in the world, with the real death toll probably much higher. Questions of origin have been widely debated with some attributing the onset of the epidemic to climatic factors and others to human transmission. None of the evidence on origin supports climatic factors. Instead, recent epidemiological and molecular-genetic evidence point to the United Nations peacekeeping troops from Nepal as the source of cholera to Haiti, following their troop rotation in early October 2010. Such findings have important policy implications for shaping future international relief efforts. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.
Soda, K; Morio, S; Tajima, K; Kitamura, K; Toba, M; Ito, A; Kihara, M; Ichikawa, S; Imai, M; Mizushima, S; Ohshige, K
In December 1995 and March 1996, we visited institutes which were conducting epidemiological studied of HIV/AIDS in Cambodia, and obtained data for further collaborative study between Japan and Cambodia. Data included information on AIDS patients and HIV infected persons, and behavioral epidemiology of CSWs (Commercial Sex Workers). The cumulative reported number of AIDS patients and HIV infected persons in Cambodia was 86 and 2,536 cases respectively in 1995. The cause of infection was mostly heterosexual contact with very few cases from injecting drug use (IDU) and other causes. The seroprevalence rate of HIV antibody among donated blood rapidly increased from 0.08% in 1991 to 4.47% in 1995, and those among CSWs and pregnant women were 37.9% and 2.6%, respectively, in 1995. The average rate of condom use among CSWs was 66%, but the rate of usual usage was only 14%. These results indicate that the HIV/AIDS epidemic had spread rapidly through CSWs, that it had been spread among peoples in communities, and that usage of condoms among CSWs was insufficient in Cambodia. Without strong countermeasures against HIV/AIDS in this country, HIV/AIDS epidemic may spread significantly to not only peoples in this country but also those in neighbouring countries in the future.
Kostiukova, N N; Bekhalo, V A
Gonorrhea in spite of its fully elucidated etiopathogenesis and available drugs for etiotropic therapy belongs to infections which are not controlled by vaccination due to absence of immunity formation. Analysis of scientific publication, statistical materials and WHO's data showed that epidemic process of gonorrhea infection depends mainly from people's behaviour, first of all, sexual. Modern epidemic process of gonorrhea infection consists from irregular increases and decreases of incidence due to various reasons. Reasons for increases of incidence appear to be simultaneous action of a range of biologic and anthropogenic factors. First reason--rapid increase of resistance of gonococci to widely used antibacterial preparations as well as synergy of pathogenic effects between HIV and gonococci; anthropogenic--wars, increase of high-risk groups due to urbanization, use of oral contraceptives, rise of prostitution, migration, inadequate access to medical care, poverty, intensification of intercourses (including hetero- and homosexual) between people, as well as demographic changes--increase of proportion of young people in population structure. Same but reciprocal factors lead to decrease of morbidity. Of them, the following were considered as most important: mass implementation of new effective antimicrobial drug as well as intensification of sanitary education, availability of early diagnostics and treatment, increase of material and cultural standards of life, decrease in number of persons belonging to high risk groups. Yet, capabilities of modern science expressed only in continuous development of new antibacterial drugs active against circulating population of gonococci, which is resistant to previously used drug.
Christina C. Chang
Full Text Available Discovered more than 100 years ago as a human pathogen, the Cryptococcus neoformans–Cryptococcus gattii (C. neoformans–C. gattii complex has seen a large global resurgence in its association with clinical disease in the last 30 years. First isolated in fermenting peach juice, and identified as a human pathogen in 1894 in a patient with bone lesions, this environmental pathogen has now found niches in soil, trees, birds, and domestic pets. Cryptococcosis is well recognized as an opportunistic infection and was first noted to be associated with reticuloendothelial cancers in the 1950s. Since then, advances in transplant immunology, medical science and surgical techniques have led to increasing numbers of solid organ transplantations (SOT and hematological stem cell transplantations being performed, and the use of biological immunotherapeutics in increasingly high-risk and older individuals, have contributed to the further rise in cryptococcosis. Globally, however, the major driver for revivification of cryptococcosis is undoubtedly the HIV epidemic, particularly in Sub-Saharan Africa where access to care and antiretroviral therapy remains limited and advanced immunodeficiency, poverty and malnutrition remains the norm. As a zoonotic disease, environmental outbreaks of both human and animal cryptococcosis have been reported, possibly driven by climate change. This is best exemplified by the resurgence of C. gattii infection in Vancouver Island, Canada, and the Pacific Northwest of the United States since 1999. Here we describe how the colliding epidemics of HIV, transplantation and immunologics, climate change and migration have contributed to the rise of cryptococcosis.
Farrahi, Katayoun; Emonet, Rémi; Cebrian, Manuel
Traditional contact tracing relies on knowledge of the interpersonal network of physical interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data assimilation, this network is generally difficult to reconstruct accurately. Communication traces obtained by mobile phones are known to be good proxies for the physical interaction network, and they may provide a valuable tool for contact tracing. Motivated by this assumption, we propose a model for contact tracing, where an infection is spreading in the physical interpersonal network, which can never be fully recovered; and contact tracing is occurring in a communication network which acts as a proxy for the first. We apply this dual model to a dataset covering 72 students over a 9 month period, for which both the physical interactions as well as the mobile communication traces are known. Our results suggest that a wide range of contact tracing strategies may significantly reduce the final size of the epidemic, by mainly affecting its peak of incidence. However, we find that for low overlap between the face-to-face and communication interaction network, contact tracing is only efficient at the beginning of the outbreak, due to rapidly increasing costs as the epidemic evolves. Overall, contact tracing via mobile phone communication traces may be a viable option to arrest contagious outbreaks.
Full Text Available Traditional contact tracing relies on knowledge of the interpersonal network of physical interactions, where contagious outbreaks propagate. However, due to privacy constraints and noisy data assimilation, this network is generally difficult to reconstruct accurately. Communication traces obtained by mobile phones are known to be good proxies for the physical interaction network, and they may provide a valuable tool for contact tracing. Motivated by this assumption, we propose a model for contact tracing, where an infection is spreading in the physical interpersonal network, which can never be fully recovered; and contact tracing is occurring in a communication network which acts as a proxy for the first. We apply this dual model to a dataset covering 72 students over a 9 month period, for which both the physical interactions as well as the mobile communication traces are known. Our results suggest that a wide range of contact tracing strategies may significantly reduce the final size of the epidemic, by mainly affecting its peak of incidence. However, we find that for low overlap between the face-to-face and communication interaction network, contact tracing is only efficient at the beginning of the outbreak, due to rapidly increasing costs as the epidemic evolves. Overall, contact tracing via mobile phone communication traces may be a viable option to arrest contagious outbreaks.
Loginov, Dmitry; Šebela, Marek
Fungal pathogens are causal agents of numerous human, animal, and plant diseases. They employ various infection modes to overcome host defense systems. Infection mechanisms of different fungi have been subjected to many comprehensive studies. These investigations have been facilitated by the development of various '-omics' techniques, and proteomics has one of the leading roles in this regard. Fungal conidia and sclerotia could be considered the most important structures for pathogenesis as their germination is one of the first steps towards a host infection. They represent interesting objects for proteomic studies because of the presence of unique proteins with unexplored biotechnological potential required for pathogen viability, development and the subsequent host infection. Proteomic peculiarities of survival structures of different fungi, including those of biotechnological significance (e.g., Asperillus fumigatus, A. nidulans, Metarhizium anisopliae), in a dormant state, as well as changes in the protein production during early stages of fungal development are the subjects of the present review. We focused on biological aspects of proteomic studies of fungal survival structures rather than on an evaluation of proteomic approaches. For that reason, proteins that have been identified in this context are discussed from the point of view of their involvement in different biological processes and possible functions assigned to them. This is the first review paper summarizing recent advances in proteomics of fungal survival structures. Copyright © 2016 Elsevier B.V. All rights reserved.
Grigoriev, Igor V.
Genomes of fungi relevant to energy and environment are in focus of the JGI Fungal Genomic Program. One of its projects, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts and pathogens) and biorefinery processes (cellulose degradation and sugar fermentation) by means of genome sequencing and analysis. New chapters of the Encyclopedia can be opened with user proposals to the JGI Community Science Program (CSP). Another JGI project, the 1000 fungal genomes, explores fungal diversity on genome level at scale and is open for users to nominate new species for sequencing. Over 400 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics will lead to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such ‘parts’ suggested by comparative genomics and functional analysis in these areas are presented here.
Grigoriev, Igor V.
Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). One of its projects, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts) by means of genome sequencing and analysis. New chapters of the Encyclopedia can be opened with user proposals to the JGI Community Sequencing Program (CSP). Another JGI project, the 1000 fungal genomes, explores fungal diversity on genome level at scale and is open for users to nominate new species for sequencing. Over 200 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.
Lugtenberg, Ben J J; Caradus, John R; Johnson, Linda J
This minireview highlights the importance of endophytic fungi for sustainable agriculture and horticulture production. Fungal endophytes play a key role in habitat adaptation of plants resulting in improved plant performance and plant protection against biotic and abiotic stresses. They encode a vast variety of novel secondary metabolites including volatile organic compounds. In addition to protecting plants against pathogens and pests, selected fungal endophytes have been used to remove animal toxicities associated with fungal endophytes in temperate grasses, to create corn and rice plants that are tolerant to a range of biotic and abiotic stresses, and for improved management of post-harvest control. We argue that practices used in plant breeding, seed treatments and agriculture, often caused by poor knowledge of the importance of fungal endophytes, are among the reasons for the loss of fungal endophyte diversity in domesticated plants and also accounts for the reduced effectiveness of some endophyte strains to confer plant benefits. We provide recommendations on how to mitigate against these negative impacts in modern agriculture. © FEMS 2016. All rights reserved. For permissions, please e-mail: email@example.com.
Hsu, Wei-Yin; Wen, Tzai-Hung; Yu, Hwa-Lung
Taiwan is located in subtropical and tropical regions with high temperature and high humidity in the summer. This kind of climatic condition is the hotbed for the propagation and spread of the dengue vector mosquito. Kaohsiung City has been the worst dengue fever epidemic city in Taiwan. During the study period, from January 1998 to December 2011, Taiwan CDC recorded 7071 locally dengue epidemic cases in Kaohsiung City, and the number of imported case is 118. Our research uses Quantile Regression, a spatial infection disease distribution, to analyze the correlation between dengue epidemic and geographic environmental factors and human society factors in Kaohsiung. According to our experiment statistics, agriculture and natural forest have a positive relation to dengue fever(5.5~34.39 and 3.91~15.52). The epidemic will rise when the ratio for agriculture and natural forest increases. Residential ratio has a negative relation for quantile 0.1 to 0.4(-0.005~-0.78), and a positive relation for quantile 0.5 to0.9(0.01~18.0) . The mean income is also a significant factor in social economy field, and it has a negative relation to dengue fever(-0.01~-0.04). Conclusion from our research is that the main factor affecting the degree of dengue fever in predilection area is the residential proportion and the ratio of agriculture and natural forest plays an important role affecting the degree of dengue fever in non predilection area. Moreover, the serious epidemic area located by regression model is the same as the actual condition in Kaohsiung. This model can be used to predict the serious epidemic area of dengue fever and provide some references for the Health Agencies
Joffe, Luna S.; Nimrichter, Leonardo
ABSTRACT Extracellular vesicles (EVs) are produced by virtually all cell types. Within the past few years, work in this field has revealed more information about fungal EVs. Fungal EVs have been shown to carry proteins, lipids, pigments, polysaccharides, and RNA; these components are known virulence factors, a fact which supports the hypothesis that fungal EVs concentrate pathogenic determinants. Additionally, recent studies have demonstrated that fungal EVs stimulate the host immune system. In this review, putative roles of fungal EVs are discussed, including their potential as vaccination tools and their possible contribution to pathogenesis in invasive fungal diseases. PMID:27390779
production, accurate diagnosis and treatment, training for caring for neurological syndromes and congenital malformations. (iii Measures for travelers: counseling, disinfestation of aircrafts and airports. (iv Sharing of information. Some inquiries have been made about the magnitude of this epidemic and its association with microcephaly and neurological disorders(4-5. It is reasonable to consider that there is an underreporting of microcephaly in the records of the Live Births Information System in Brazil. It is also to be expected that, after the national alert, the number of suspected cases would rise. When there is an increase or the implementation of surveillance, this always results in higher sensitivity of detection of suspected/reported cases with an increase in false positives. For these reasons, it is possible to say that part of the increase in reported cases of microcephaly may be attributable to the current intense surveillance. What is inconceivable, however, is that the prevalence of microcephaly in northeastern Brazil is 10 to 20 times higher than in other countries(6. At present, there are hypotheses that the Zika virus may have an etiologic and/or pathophysiological role for these events, which is usually rare. What seems indisputable is the gravity of the situation. Health managers cannot wait for high-level scientific evidence. Care and prudence when assessing is advisable, and the same goes for avoiding premature conclusions. However, given the potential threat, we have a duty to at least protect pregnant women and their fetuses. The current situation poses many challenges that we need to face and it seems logical that Brazil take the lead in beginning the actions. We recognize in our history both the success in the fight against yellow fever early in the last century and also our recent inefficiency in the fight against the Aedes aegypti mosquito to control dengue and chikungunya. It is necessary to create, renew, and
Jemi, Renhart; Barus, Ade Irma; Nuwa, Sarinah, Luhan, Gimson
Ujung Atap is an herb that have distinctive odor on its leaves. The plant's essential oil contains bioactive compounds but has not been investigated its anti-fungal activity against Pleurotus ostreatus. Essential oil from Ujung Atap leaves is one environmentally friendly natural preservative. This study consisted of distillation Ujung Atap leaves with boiled method, determining the number of acid, essential oil ester, and anti-fungal activity against Pleurotus ostreatus. Analysis of the data to calculate anti-fungal activity used probit analysis method to determine the IC50. Results for the distillation of leaves Ujung Atap produce essential oil yield of 0.071% and the average yield of the acid number and the ester of essential oils Ujung Atap leaves are 5.24 and 12.15. Anti-fungal activity Pleurotus ostreatus at a concentration of 1000 µg/mL, 100 µg/mL, 75 µg/mL, 50 µg/mL and 100 µg/mL BA defunct or fungi was declared dead, while at a concentration of 25 µg/mL, 10 µg/mL and 5 µg/mL still occur inhibitory processes. Results obtained probit analysis method IC50 of 35.48 mg/mL; means the essential oil of Ujung Atap leaf can inhibit fungal growth by 50 percent to 35.48 µg/mL concentration.
Sun, Hui; Terhonen, Eeva; Kovalchuk, Andriy; Tuovila, Hanna; Chen, Hongxin; Oghenekaro, Abbot O; Heinonsalo, Jussi; Kohler, Annegret; Kasanen, Risto; Vasander, Harri; Asiegbu, Fred O
Boreal peatlands play a crucial role in global carbon cycling, acting as an important carbon reservoir. However, little information is available on how peatland microbial communities are influenced by natural variability or human-induced disturbances. In this study, we have investigated the fungal diversity and community structure of both the organic soil layer and buried wood in boreal forest soils using high-throughput sequencing of the internal transcribed spacer (ITS) region. We have also compared the fungal communities during the primary colonization of wood with those of the surrounding soils. A permutational multivariate analysis of variance (PERMANOVA) confirmed that the community composition significantly differed between soil types (Pstructure (Psoil nutrients (Ca [P= 0.002], Fe [P= 0.003], and P [P= 0.003]) within the site was an important factor in the fungal community composition. The species richness in wood was significantly lower than in the corresponding soil (P< 0.004). The results of the molecular identification were supplemented by fruiting body surveys. Seven of the genera of Agaricomycotina identified in our surveys were among the top 20 genera observed in pyrosequencing data. Our study is the first, to our knowledge, fungal high-throughput next-generation sequencing study performed on peatlands; it further provides a baseline for the investigation of the dynamics of the fungal community in the boreal peatlands. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Zhang, Tao; Zhao, Yun-Long; Zhao, Jian-Hua; Wang, Sheng; Jin, Yun; Chen, Zhong-Qi; Fang, Yuan-Yuan; Hua, Chen-Lei; Ding, Shou-Wei; Guo, Hui-Shan
Plant pathogenic fungi represent the largest group of disease-causing agents on crop plants, and are a constant and major threat to agriculture worldwide. Recent studies have shown that engineered production of RNA interference (RNAi)-inducing dsRNA in host plants can trigger specific fungal gene silencing and confer resistance to fungal pathogens 1-7 . Although these findings illustrate efficient uptake of host RNAi triggers by pathogenic fungi, it is unknown whether or not such an uptake mechanism has been evolved for a natural biological function in fungus-host interactions. Here, we show that in response to infection with Verticillium dahliae (a vascular fungal pathogen responsible for devastating wilt diseases in many crops) cotton plants increase production of microRNA 166 (miR166) and miR159 and export both to the fungal hyphae for specific silencing. We found that two V. dahliae genes encoding a Ca 2+ -dependent cysteine protease (Clp-1) and an isotrichodermin C-15 hydroxylase (HiC-15), and targeted by miR166 and miR159, respectively, are both essential for fungal virulence. Notably, V. dahliae strains expressing either Clp-1 or HiC-15 rendered resistant to the respective miRNA exhibited drastically enhanced virulence in cotton plants. Together, our findings identify a novel defence strategy of host plants by exporting specific miRNAs to induce cross-kingdom gene silencing in pathogenic fungi and confer disease resistance.
Full Text Available Chitin is an essential structural polysaccharide of fungal pathogens and parasites, but its role in human immune responses remains largely unknown. It is the second most abundant polysaccharide in nature after cellulose and its derivatives today are widely used for medical and industrial purposes. We analysed the immunological properties of purified chitin particles derived from the opportunistic human fungal pathogen Candida albicans, which led to the selective secretion of the anti-inflammatory cytokine IL-10. We identified NOD2, TLR9 and the mannose receptor as essential fungal chitin-recognition receptors for the induction of this response. Chitin reduced LPS-induced inflammation in vivo and may therefore contribute to the resolution of the immune response once the pathogen has been defeated. Fungal chitin also induced eosinophilia in vivo, underpinning its ability to induce asthma. Polymorphisms in the identified chitin receptors, NOD2 and TLR9, predispose individuals to inflammatory conditions and dysregulated expression of chitinases and chitinase-like binding proteins, whose activity is essential to generate IL-10-inducing fungal chitin particles in vitro, have also been linked to inflammatory conditions and asthma. Chitin recognition is therefore critical for immune homeostasis and is likely to have a significant role in infectious and allergic disease.
Gomes, Teresa; Pereira, José Alberto; Benhadi, Jacinto; Lino-Neto, Teresa; Baptista, Paula
The diversity and factors influencing fungal assemblages in phyllosphere of Mediterranean tree species have been barely studied, especially when endophytic and epiphytic communities are simultaneously considered. In this work, the endophytic and epiphytic fungal communities from olive tree phyllosphere were studied. This tree species is natural from the Mediterranean region and adapted to grow under adverse climatic conditions. The main objectives were to determine whether there are differences between both fungal communities and to examine whether different abiotic (climate-related) and biotic (plant organs) factors play a pivotal role in structuring these communities. Both communities differed in size and composition, with epiphytic community being richer and more abundant, displaying also a dominance of melanized fungi. Season was the major driver of community composition, especially of epiphytes. Other drivers shaping epiphytes were wind speed and temperature, while plant organ, rainfall, and temperature were the major drivers for endophytic composition. In contrast, canopy orientation caused slight variations in community composition of fungi, but with distinct effects in spring and autumn seasons. In conclusion, epiphytic and endophytic communities are not driven by the same factors. Several sources of variation undergo complex interactions to form and maintain phyllosphere fungal community in Mediterranean climates. Climatic parameters have influence on these fungal communities, suggesting that they are likely to be affected by climate changes in a near future.
Janoušková, Martina; Püschel, David; Hujslová, Martina; Slavíková, Renata; Jansa, Jan
Monitoring populations of arbuscular mycorrhizal fungi (AMF) in roots is a pre-requisite for improving our understanding of AMF ecology and functioning of the symbiosis in natural conditions. Among other approaches, quantification of fungal DNA in plant tissues by quantitative real-time PCR is one of the advanced techniques with a great potential to process large numbers of samples and to deliver truly quantitative information. Its application potential would greatly increase if the samples could be preserved by drying, but little is currently known about the feasibility and reliability of fungal DNA quantification from dry plant material. We addressed this question by comparing quantification results based on dry root material to those obtained from deep-frozen roots of Medicago truncatula colonized with Rhizophagus sp. The fungal DNA was well conserved in the dry root samples with overall fungal DNA levels in the extracts comparable with those determined in extracts of frozen roots. There was, however, no correlation between the quantitative data sets obtained from the two types of material, and data from dry roots were more variable. Based on these results, we recommend dry material for qualitative screenings but advocate using frozen root materials if precise quantification of fungal DNA is required.
Full Text Available BACKGROUND: Fungi strongly influence ecosystem structure and functioning, playing a key role in many ecological services as decomposers, plant mutualists and pathogens. The Mediterranean area is a biodiversity hotspot that is increasingly threatened by intense land use. Therefore, to achieve a balance between conservation and human development, a better understanding of the impact of land use on the underlying fungal communities is needed. METHODOLOGY/PRINCIPAL FINDINGS: We used parallel pyrosequencing of the nuclear ribosomal its regions to characterize the fungal communities in five soils subjected to different anthropogenic impact in a typical mediterranean landscape: a natural cork-oak forest, a pasture, a managed meadow, and two vineyards. Marked differences in the distribution of taxon assemblages among the different sites and communities were found. Data analyses consistently indicated a sharp distinction of the fungal community of the cork oak forest soil from those described in the other soils. Each soil showed features of the fungal assemblages retrieved which can be easily related to the above-ground settings: ectomycorrhizal phylotypes were numerous in natural sites covered by trees, but were nearly completely missing from the anthropogenic and grass-covered sites; similarly, coprophilous fungi were common in grazed sites. CONCLUSIONS/SIGNIFICANCE: Data suggest that investigation on the below-ground fungal community may provide useful elements on the above-ground features such as vegetation coverage and agronomic procedures, allowing to assess the cost of anthropogenic land use to hidden diversity in soil. Datasets provided in this study may contribute to future searches for fungal bio-indicators as biodiversity markers of a specific site or a land-use degree.
Santos-Figueroa, G.; Bolaños-Rosero, B.; Mayol-Bracero, O. L.
Fungal spores are a major component of primary biogenic aerosol particles that are emitted to the atmosphere, are ubiquitous, and play an important role in the chemistry and physics of the atmosphere, climate, and public health. Every year, during summer months, African dust (AD) particles are transported to the Caribbean region causing an increase in the concentrations of particulate matter in the atmosphere. AD is one of the most important natural sources of mineral particulate matter at the global scale, and many investigations suggest that it has the ability to transport dust-associated biological particles through long distances. The relationship between AD incursions and the concentration of fungal spores in the Caribbean region is poorly understood. In order to investigate the effects of AD incursions on fungal spore's emissions, fungal spore concentrations were monitored using a Burkard spore trap at the tropical montane cloud forest of Pico del Este at El Yunque National Forest, Puerto Rico. The presence of AD was supported with satellite images of aerosol optical thickness, and with the results from the air masses backward trajectories calculated with the NOAA HYSPLIT model. Basidiospores and Ascospores comprised the major components of the total spore's concentrations, up to a maximum of 98%, during both AD incursions and background days. A considerably decrease in the concentration of fungal spores during AD events was observed. Ergosterol, biomarker for measuring fungal biomass, concentrations were determined in aerosols that were sampled at a marine site, Cabezas de San Juan Nature Reserve, in Fajardo Puerto Rico, and at an urban site, Facundo Bueso building at the University of Puerto Rico. Additional efforts to understand the relationship between the arrival of AD to the Caribbean and a decrease in spore's concentrations are needed in order to investigate changes in local spore's vs the contribution of long-range spores transported within the AD.
Wheeler, Matthew L; Limon, Jose J; Bar, Agnieszka S; Leal, Christian A; Gargus, Matthew; Tang, Jie; Brown, Jordan; Funari, Vincent A; Wang, Hanlin L; Crother, Timothy R; Arditi, Moshe; Underhill, David M; Iliev, Iliyan D
Compared to bacteria, the role of fungi within the intestinal microbiota is poorly understood. In this study we investigated whether the presence of a "healthy" fungal community in the gut is important for modulating immune function. Prolonged oral treatment of mice with antifungal drugs resulted in increased disease severity in acute and chronic models of colitis, and also exacerbated the development of allergic airway disease. Microbiota profiling revealed restructuring of fungal and bacterial communities. Specifically, representation of Candida spp. was reduced, while Aspergillus, Wallemia, and Epicoccum spp. were increased. Oral supplementation with a mixture of three fungi found to expand during antifungal treatment (Aspergillus amstelodami, Epicoccum nigrum, and Wallemia sebi) was sufficient to recapitulate the exacerbating effects of antifungal drugs on allergic airway disease. Taken together, these results indicate that disruption of commensal fungal populations can influence local and peripheral immune responses and enhance relevant disease states. Copyright © 2016 Elsevier Inc. All rights reserved.
Looby, Caitlin I; Eaton, William D
Bromelia pinguin (Bromeliaceae) is a terrestrial bromeliad commonly found under forest stands throughout the Neotropics that has been shown to have antifungal activity in vitro. We have hypothesized that this bromeliad would also have an effect on the fungal populations in nearby soil by decreasing fungaldiversity and negatively impacting C and N cycle-related activities. A previous study in the lowland forest of Costa Rica showed the soil beneath these bromeliads had decreased fungal ITS DNA and differences in C and N levels compared to adjacent primary forest soils. In this follow-up study, we found that the bromeliad soils had lower rates of C and N biomass development and lower phenol oxidase activity (suggesting less decreased fungal decomposition activity). The results of T-RFLP and cloning-based taxonomic analyses showed the community level diversity and abundance of fungal ITS DNA was less in bromeliad soils. Sequence analysis of fungal ITS DNA clones showed marked differences in fungal community structure between habitats of Basidiomycota (Tremellales, Agricales, Thelephorales), Ascomycota (Helotiales), and Zycomycota populations. The data show there to be differences in the soil nutrient dynamics and fungal community structure and activity associated with these bromeliads, as compared to the adjacent primary forest. This suggests the possibility that the anti-fungal activity of the bromeliad extends into the soil. The bromeliad-dense regions of these primary forest habitats provide a unique natural micro-habitat within the forests and the opportunity to better identify the role of fungal communities in the C and N cycles in tropical soils.
Kirkpatrick, Christine L.; Parsley, Nicole C.; Bartges, Tessa E.; Cooke, Madeline E.; Evans, Wilaysha S.; Heil, Lilian R.; Smith, Thomas J.; Hicks, Leslie M.
Fungal secondary metabolites represent a rich and largely untapped source for bioactive molecules, including peptides with substantial structural diversity and pharmacological potential. As methods proceed to take a deep dive into fungal genomes, complimentary methods to identify bioactive components are required to keep pace with the expanding fungal repertoire. We developed PepSAVI-MS to expedite the search for natural product bioactive peptides and herein demonstrate proof-of-principle applicability of the pipeline for the discovery of bioactive peptides from fungal secretomes via identification of the antifungal killer toxin KP4 from Ustilago maydis P4. This work opens the door to investigating microbial secretomes with a new lens, and could have broad applications across human health, agriculture, and food safety. [Figure not available: see fulltext.
Salvachúa, Davinia; Katahira, Rui; Cleveland, Nicholas S.; Khanna, Payal; Resch, Michael G.; Black, Brenna A.; Purvine, Samuel O.; Zink, Erika M.; Prieto, Alicia; Martínez, María J.; Martínez, Angel T.; Simmons, Blake A.; Gladden, John M.; Beckham, Gregg T.
In Nature, powerful oxidative enzymes secreted by white rot fungi and some bacteria catalyze lignin depolymerization and some microbes are able to catabolize the resulting aromatic compounds as carbon and energy sources. Taken together, these two processes offer a potential route for microbial valorization of lignin. However, many challenges remain in realizing this concept, including that oxidative enzymes responsible for lignin depolymerization also catalyze polymerization of low molecular weight (LMW) lignin. Here, multiple basidiomycete secretomes were screened for ligninolytic enzyme activities in the presence of a residual lignin solid stream from a corn stover biorefinery, dubbed DMR-EH (Deacetylation, Mechanical Refining, and Enzymatic Hydrolysis) lignin. Two selected fungal secretomes, with high levels of laccases and peroxidases, were utilized for DMR-EH lignin depolymerization assays. The secretome from Pleurotus eryngii, which exhibited the highest laccase activity, reduced the lignin average molecular weight by 63% and 75% at pH 7 compared to the Mw of the control treated at the same conditions and the initial DMR-EH lignin, respectively, and was applied in further depolymerization assays as a function of time. As repolymerization was observed after 3 days of incubation, an aromatic-catabolic microbe (Pseudomonas putida KT2440) was incubated with the fungal secretome and DMR-EH lignin. These experiments demonstrated that the presence of the bacterium enhances lignin depolymerization, likely due to bacterial catabolism of LMW lignin, which may partially prevent repolymerization. In addition, proteomics was also applied to the P. eryngii secretome to identify the enzymes present in the fungal cocktail utilized for the depolymerization assays, which highlighted a significant number of glucose/ methanol/choline (GMC) oxidoreductases and laccases. Overall, this study demonstrates that ligninolytic enzymes can be used to partially depolymerize a solid, high
Calvo, Ana M.; Cary, Jeffrey W.
Fungal secondary metabolism and morphological development have been shown to be intimately associated at the genetic level. Much of the literature has focused on the co-regulation of secondary metabolite production (e.g., sterigmatocystin and aflatoxin in Aspergillus nidulans and Aspergillus flavus, respectively) with conidiation or formation of sexual fruiting bodies. However, many of these genetic links also control sclerotial production. Sclerotia are resistant structures produced by a number of fungal genera. They also represent the principal source of primary inoculum for some phytopathogenic fungi. In nature, higher plants often concentrate secondary metabolites in reproductive structures as a means of defense against herbivores and insects. By analogy, fungi also sequester a number of secondary metabolites in sclerotia that act as a chemical defense system against fungivorous predators. These include antiinsectant compounds such as tetramic acids, indole diterpenoids, pyridones, and diketopiperazines. This chapter will focus on the molecular mechanisms governing production of secondary metabolites and the role they play in sclerotial development and fungal ecology, with particular emphasis on Aspergillus species. The global regulatory proteins VeA and LaeA, components of the velvet nuclear protein complex, serve as virulence factors and control both development and secondary metabolite production in many Aspergillus species. We will discuss a number of VeA- and LaeA-regulated secondary metabolic gene clusters in A. flavus that are postulated to be involved in sclerotial morphogenesis and chemical defense. The presence of multiple regulatory factors that control secondary metabolism and sclerotial formation suggests that fungi have evolved these complex regulatory mechanisms as a means to rapidly adapt chemical responses to protect sclerotia from predators, competitors and other environmental stressors. PMID:25762985
Ana M. Calvo
Full Text Available Fungal secondary metabolism and morphological development have been shown to be intimately associated at the genetic level. Much of the literature has focused on the co-regulation of secondary metabolite production (e.g. sterigmatocystin and aflatoxin in Aspergillus nidulans and Aspergillus flavus, respectively with conidiation or formation of sexual fruiting bodies. However, many of these genetic links also control sclerotial production. Sclerotia are resistant structures produced by a number of fungal genera. They also represent the principal source of primary inoculum for some phytopathogenic fungi. In nature, higher plants often concentrate secondary metabolites in reproductive structures as a means of defense against herbivores and insects. By analogy, fungi also sequester a number of secondary metabolites in sclerotia that act as a chemical defense system against fungivorous predators. These include antiinsectant compounds such as tetramic acids, indole diterpenoids, pyridones and diketopiperazines. This chapter will focus on the molecular mechanisms governing production of secondary metabolites and the role they play in sclerotial development and fungal ecology, with particular emphasis on Aspergillus species. The global regulatory proteins VeA and LaeA, components of the velvet nuclear protein complex, serve as virulence factors and control both development and secondary metabolite production in many Aspergillus species. We will discuss a number of VeA and LaeA-regulated secondary metabolic gene clusters in A. flavus that are postulated to be involved in sclerotial morphogenesis and chemical defense. The presence of multiple regulatory factors that control secondary metabolism and sclerotial formation suggests that fungi have evolved these complex regulatory mechanisms as a means to rapidly adapt chemical responses to protect sclerotia from predators, competitors and other environmental stresses.
1) Fungal nail infection, or onychomycosis, mainly affects toenails. Infections are generally asymptomatic. Spontaneous regressions, but also complications, appear to be rare. Discomfort and cosmetic complaint are occasionally reported; 2) After a review of the literature based on the standard Prescrire procedure, we examined the diagnosis and management of fungal nail infections; 3) Clinical signs of fungal nail infections are non-specific. Alternative diagnoses include psoriasis and nail microtrauma. Nail hyperkeratosis and leukonychia are useful diagnostic pointers. Matrix involvement has important implications in the choice of treatment; 4) Detection of fungal structures by direct examination of a nail sample is strongly suggestive of fungal nail infection. In contrast, cases of negative direct examination with positive culture must be interpreted with caution, as contamination is frequent; 5) Antifungal lacquers (5% amorolfine and 8% ciclopirox) applied to the nails cure about 30% of fungal infections and sometimes cause mild irritation. There is no firm evidence that these solutions are any more effective than other topical antifungals applied daily to the affected nail. Trimming, filing or grinding the nail, in addition to these drug treatments, is likely to be beneficial, but these measures have not been evaluated; 6) Chemical nail destruction with a combination of urea and bifonazole, followed by treatment with an antifungal ointment, can be used when the nail is markedly thickened. Non-comparative trials have shown cure rates close to 70% at three months when the matrix is not involved, and 40% with matrix involvement. Drug application is inconvenient and local reactions are frequent. Surgical nail avulsion carries a risk of local infection and permanent nail dystrophy; 7) Oral terbinafine is effective in more than 50% of cases but its cutaneous, hepatic and haematological adverse effects are severe in about 1 in 2000 patients and can be life
Toma, Paolo; Colafati, Giovanna Stefania; D' Andrea, Maria Luisa [IRCCS Bambino Gesu Children' s Hospital, Department of Imaging, Rome (Italy); Bertaina, Alice; Mastronuzzi, Angela [IRCCS Bambino Gesu Children' s Hospital, Department of Pediatric Hematology/Oncology and Transfusion Medicine, Rome (Italy); Castagnola, Elio [IRCCS Istituto Giannina Gaslini, Department of Infective Diseases, Genoa (Italy); Finocchi, Andrea [IRCCS Bambino Gesu Children' s Hospital, Department of Pediatrics, Rome (Italy); Lucidi, Vincenzina [IRCCS Bambino Gesu Children' s Hospital, Cystic Fibrosis Center, Rome (Italy); Granata, Claudio [IRCCS Istituto Giannina Gaslini, Department of Pediatric Radiology, Genoa (Italy)
Fungal infections of the lungs are relatively common and potentially life-threatening conditions in immunocompromised children. The role of imaging in children with lung mycosis is to delineate the extension of pulmonary involvement, to assess response to therapy, and to monitor for adverse sequelae such as bronchiectasis and cavitation. The aim of this paper is to show imaging findings in a series of patients with fungal pneumonia from two tertiary children's hospitals, to discuss differential diagnoses and to show how imaging findings can vary depending on the host immune response. (orig.)
Full Text Available Objective: The aim of this study was to examine the synchrony of influenza epidemics between Hong Kong and Shenzhen, two neighboring subtropical cities in South China. Methods: Laboratory-confirmed influenza data for the period January 2006 to December 2016 were obtained from the Shenzhen Center for Disease Control and Prevention and the Department of Health in Hong Kong. The population data were retrieved from the 2011 population censuses. The weekly rates of laboratory-confirmed influenza cases were compared between Shenzhen and Hong Kong. Results: Unsynchronized influenza epidemics between Hong Kong and Shenzhen were frequently observed during the study period. Influenza A/H1N1 caused a more severe pandemic in Hong Kong in 2009, but the subsequent seasonal epidemics showed similar magnitudes in both cities. Two influenza A/H3N2 dominant epidemic waves were seen in Hong Kong in 2015, but these epidemics were very minor in Shenzhen. More influenza B epidemics occurred in Shenzhen than in Hong Kong. Conclusions: Influenza epidemics appeared to be unsynchronized between Hong Kong and Shenzhen most of the time. Given the close geographical locations of these two cities, this could be due to the strikingly different age structures of their populations. Keywords: Influenza epidemics, Synchrony, Shenzhen, Hong Kong
Risk from the frontlines of a hidden epidemic sexuality, masculinities and social pressures among men who have sex with men in South Africa: an overview. ... These factors are discussed in this paper with stress put particularly on the hiddenness of the MSM HIV epidemic, and it is concluded that the complex mix of factors ...
Epidemic meningococcal meningitis is a major public health problem still affecting tropical countries, particularly in Sub-Saharan Africa, which lies within African meningitis belt. Repeated large scale epidemics of CSM have been reported in northern Nigeria for the past four decades. It is one of the important causes of ...
G. Magiorkinis (Gkikas); K. Angelis (Konstantinos); I. Mamais (Ioannis); Katzourakis, A. (Aris); A. Hatzakis (Angelos); J. Albert (Jan); Lawyer, G. (Glenn); O. Hamouda (Osamah); D. Struck (Daniel); J. Vercauteren (Jurgen); A. Wensing (Amj); I. Alexiev (Ivailo); B. Åsjö (Birgitta); C. Balotta (Claudia); Gomes, P. (Perpétua); R.J. Camacho (Ricardo Jorge); S. Coughlan (Suzie); A. Griskevicius (Algirdas); Z. Grossman (Zehava); Horban, A. (Anders); L.G. Kostrikis (Leondios); Lepej, S.J. (Snjezana J.); K. Liitsola (Kirsi); M. Linka (Marek); C. Nielsen; D. Otelea (Dan); R. Paredes (Roger); M. Poljak (Mario); E. Puchhammer-Stöckl (Elisabeth); J.C. Schmit; A. Sonnerborg (Anders); D. Stanekova (Danica); M. Stanojevic (Maja); Stylianou, D.C. (Dora C.); C.A.B. Boucher (Charles); Nikolopoulos, G. (Georgios); Vasylyeva, T. (Tetyana); Friedman, S.R. (Samuel R.); D.A.M.C. van de Vijver (David); G. Angarano (Guiseppe); M.L. Chaix (Marie Laure); A. de Luca (Andrea); K. Korn (Klaus); Loveday, C. (Clive); V. Soriano (Virtudes); S. Yerly (Sabine); M. Zazzi; A.M. Vandamme (Anne Mieke); D. Paraskevis (Dimitrios)
textabstractHuman immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa
Magiorkinis, Gkikas; Angelis, Konstantinos; Mamais, Ioannis; Katzourakis, Aris; Hatzakis, Angelos; Albert, Jan; Lawyer, Glenn; Hamouda, Osamah; Struck, Daniel; Vercauteren, Jurgen; Wensing, Annemarie; Alexiev, Ivailo; Åsjö, Birgitta; Balotta, Claudia; Gomes, Perpétua; Camacho, Ricardo J.; Coughlan, Suzie; Griskevicius, Algirdas; Grossman, Zehava; Horban, Anders; Kostrikis, Leondios G.; Lepej, Snjezana J.; Liitsola, Kirsi; Linka, Marek; Nielsen, Claus; Otelea, Dan; Paredes, Roger; Poljak, Mario; Puchhammer-Stöckl, Elizabeth; Schmit, Jean Claude; Sönnerborg, Anders; Staneková, Danica; Stanojevic, Maja; Stylianou, Dora C.; Boucher, Charles A B; Nikolopoulos, Georgios; Vasylyeva, Tetyana; Friedman, Samuel R.; van de Vijver, David; Angarano, Gioacchino; Chaix, Marie Laure; de Luca, Andrea; Korn, Klaus; Loveday, Clive; Soriano, Vincent; Yerly, Sabine; Zazzi, Mauricio; Vandamme, Anne Mieke; Paraskevis, Dimitrios
Human immunodeficiency virus type 1 (HIV-1) was discovered in the early 1980s when the virus had already established a pandemic. For at least three decades the epidemic in the Western World has been dominated by subtype B infections, as part of a sub-epidemic that traveled from Africa through Haiti
Visser, T.; Dijkman, J.J.; Grijpink, J.H.A.M.|info:eu-repo/dai/nl/095130861; Plomp, M.G.A.|info:eu-repo/dai/nl/313946809; Seignette, P.
This article presents the results of the chain analysis of the epidemic control chain according to the method of chain-computerisation. The goal of the epidemic control chain is to prevent the disruption of society that is caused by disease or excess of preventive measures. The current
We present the travelling wave solution for a Susceptible, Exposed, Infective and Removed (SEIR) epidemic disease model. For this SEIR model, the disease is driven by both the latent and infective class (the diffusion term is included in both classes). The population is closed. Keywords: Epidemic model, spatial spread, ...
May 4, 1991 ... During the cholera epidemic in South Africa, 1980-1987,. 25251 cases of cholera were bacteriologically proven. The case-fatality rate was 1,4%. Outbreaks occurred in the summer rainfall season. Age-specific aUack rates followed the pattern typically found during the 'epidemic phase' of the disease in.
Lu, Dan; Yang, Shunkun; Zhang, Jiaquan; Wang, Huijuan; Li, Daqing
Epidemic propagation on complex networks has been widely investigated, mostly with invariant parameters. However, the process of epidemic propagation is not always constant. Epidemics can be affected by various perturbations and may bounce back to its original state, which is considered resilient. Here, we study the resilience of epidemics on networks, by introducing a different infection rate λ 2 during SIS (susceptible-infected-susceptible) epidemic propagation to model perturbations (control state), whereas the infection rate is λ 1 in the rest of time. Noticing that when λ 1 is below λ c , there is no resilience in the SIS model. Through simulations and theoretical analysis, we find that even for λ 2 < λ c , epidemics eventually could bounce back if the control duration is below a threshold. This critical control time for epidemic resilience, i.e., cd max , seems to be predicted by the diameter (d) of the underlying network, with the quantitative relation cd max ∼ d α . Our findings can help to design a better mitigation strategy for epidemics.
Lu, Dan; Yang, Shunkun; Zhang, Jiaquan; Wang, Huijuan; Li, Daqing
Epidemic propagation on complex networks has been widely investigated, mostly with invariant parameters. However, the process of epidemic propagation is not always constant. Epidemics can be affected by various perturbations and may bounce back to its original state, which is considered resilient. Here, we study the resilience of epidemics on networks, by introducing a different infection rate λ2 during SIS (susceptible-infected-susceptible) epidemic propagation to model perturbations (control state), whereas the infection rate is λ1 in the rest of time. Noticing that when λ1 is below λc, there is no resilience in the SIS model. Through simulations and theoretical analysis, we find that even for λ2 < λc, epidemics eventually could bounce back if the control duration is below a threshold. This critical control time for epidemic resilience, i.e., cdmax, seems to be predicted by the diameter (d) of the underlying network, with the quantitative relation cdmax ˜ dα. Our findings can help to design a better mitigation strategy for epidemics.
During the cholera epidemic in South Africa, 1980-1987, 25251 cases of cholera were bacteriologically proven. The case-fatality rate was 1,4%. Outbreaks occurred in the summer rainfall season. Age-specific aUack rates followed the pattern typically found during the 'epidemic phase' of the disease in most years. The vast ...
In some cases, mean:2$D method is used to determine thresholds for malaria epidemics. This involves the calculation of the long-term mean of monthly malaria cases (derived from a minimum 5- year data set from which abnormal years have been excluded) and an epidemic threshold set at two times the standard deviation ...
Hisham Beshara Halasa, Tariq; Bøtner, Anette; Mortensen, Sten
resulted in marginal improvements to the control of the epidemics. However, adding testing of dead animals in the protection and surveillance zones was predicted to be the optimal control scenario for an ASF epidemic in industrialized swine populations without contact to wild boar. This optimal scenario...
The article uses case studies, extracted from published epidemic stories and interprets these cases from a feminist and power analytical framework. The results suggest that while a disease or an epidemic affect a group of individuals, systemic factors regarding responsible governance and the role of national politics and ...
Balci Mehmet Ali
Full Text Available In this study, we present an epidemic model that characterizes the behavior of a financial network of globally operating stock markets. Since the long time series have a global memory effect, we represent our model by using the fractional calculus. This model operates on a network, where vertices are the stock markets and edges are constructed by the correlation distances. Thereafter, we find an analytical solution to commensurate system and use the well-known differential transform method to obtain the solution of incommensurate system of fractional differential equations. Our findings are confirmed and complemented by the data set of the relevant stock markets between 2006 and 2016. Rather than the hypothetical values, we use the Hurst Exponent of each time series to approximate the fraction size and graph theoretical concepts to obtain the variables.
Wu, ChienHsing; Kao, Shu-Chen; Shih, Chia-Hung; Kan, Meng-Hsuan
By using a quantitative approach, this study examines the applicability of data mining technique to discover knowledge from open data related to Taiwan's dengue epidemic. We compare results when Google trend data are included or excluded. Data sources are government open data, climate data, and Google trend data. Research findings from analysis of 70,914 cases are obtained. Location and time (month) in open data show the highest classification power followed by climate variables (temperature and humidity), whereas gender and age show the lowest values. Both prediction accuracy and simplicity decrease when Google trends are considered (respectively 0.94 and 0.37, compared to 0.96 and 0.46). The article demonstrates the value of open data mining in the context of public health care. Copyright © 2018 Elsevier B.V. All rights reserved.
Yang, Lu-Xing; Yang, Xiaofan
This paper addresses the epidemiological modeling of computer viruses. By incorporating the effect of removable storage media, considering the possibility of connecting infected computers to the Internet, and removing the conservative restriction on the total number of computers connected to the Internet, a new epidemic model is proposed. Unlike most previous models, the proposed model has no virus-free equilibrium and has a unique endemic equilibrium. With the aid of the theory of asymptotically autonomous systems as well as the generalized Poincare-Bendixson theorem, the endemic equilibrium is shown to be globally asymptotically stable. By analyzing the influence of different system parameters on the steady number of infected computers, a collection of policies is recommended to prohibit the virus prevalence.
Full Text Available Rabies is a serious concern to public health and wildlife management worldwide. Over the last three decades, various mathematical models have been proposed to study the transmission dynamics of rabies. In this paper we provide a mini-review on some reaction-diffusion models describing the spatial spread of rabies among animals. More specifically, we introduce the susceptible-exposed-infectious models for the spatial transmission of rabies among foxes (Murray et al., 1986, the spatiotemporal epidemic model for rabies among raccoons (Neilan and Lenhart, 2011, the diffusive rabies model for skunk and bat interactions (Bonchering et al., 2012, and the reaction-diffusion model for rabies among dogs (Zhang et al., 2012. Numerical simulations on the spatiotemporal dynamics of these models from these papers are presented.
Schultz et al (2008) raised the question whether regression into autism is triggered, not by the measles-mumps-rubella (MMR) vaccine, but by acetaminophen (Tylenol) given for its fever and pain. Considerable evidence supports this contention, most notably the exponential rise in the incidence of autism since 1980, when acetaminophen began to replace aspirin for infants and young children. The impetus for this shift - a Centers for Disease Control and Prevention warning that aspirin was associated with Reye's syndrome - has since been compellingly debunked. If aspirin is not to be feared as a cause of Reyes syndrome, and acetaminophen is to be feared as a cause of autism, can the autism epidemic be reversed by replacing acetaminophen with aspirin or other remedies?
Lejeune, Gaël; Brixtel, Romain; Doucet, Antoine; Lucas, Nadine
This paper presents a multilingual news surveillance system applied to tele-epidemiology. It has been shown that multilingual approaches improve timeliness in detection of epidemic events across the globe, eliminating the wait for local news to be translated into major languages. We present here a system to extract epidemic events in potentially any language, provided a Wikipedia seed for common disease names exists. The Daniel system presented herein relies on properties that are common to news writing (the journalistic genre), the most useful being repetition and saliency. Wikipedia is used to screen common disease names to be matched with repeated characters strings. Language variations, such as declensions, are handled by processing text at the character-level, rather than at the word level. This additionally makes it possible to handle various writing systems in a similar fashion. As no multilingual ground truth existed to evaluate the Daniel system, we built a multilingual corpus from the Web, and collected annotations from native speakers of Chinese, English, Greek, Polish and Russian, with no connection or interest in the Daniel system. This data set is available online freely, and can be used for the evaluation of other event extraction systems. Experiments for 5 languages out of 17 tested are detailed in this paper: Chinese, English, Greek, Polish and Russian. The Daniel system achieves an average F-measure of 82% in these 5 languages. It reaches 87% on BEcorpus, the state-of-the-art corpus in English, slightly below top-performing systems, which are tailored with numerous language-specific resources. The consistent performance of Daniel on multiple languages is an important contribution to the reactivity and the coverage of epidemiological event detection systems. Most event extraction systems rely on extensive resources that are language-specific. While their sophistication induces excellent results (over 90% precision and recall), it restricts their
Pinto, Oscar A.; Muñoz, Miguel A.
Some epidemics have been empirically observed to exhibit outbreaks of all possible sizes, i.e., to be scale-free or scale-invariant. Different explanations for this finding have been put forward; among them there is a model for “accidental pathogens” which leads to power-law distributed outbreaks without apparent need of parameter fine tuning. This model has been claimed to be related to self-organized criticality, and its critical properties have been conjectured to be related to directed percolation. Instead, we show that this is a (quasi) neutral model, analogous to those used in Population Genetics and Ecology, with the same critical behavior as the voter-model, i.e. the theory of accidental pathogens is a (quasi)-neutral theory. This analogy allows us to explain all the system phenomenology, including generic scale invariance and the associated scaling exponents, in a parsimonious and simple way. PMID:21760930
Pérez-Espigares, Carlos; Marcuzzi, Matteo; Gutiérrez, Ricardo; Lesanovsky, Igor
We explore the nonequilibrium evolution and stationary states of an open many-body system that displays epidemic spreading dynamics in a classical and a quantum regime. Our study is motivated by recent experiments conducted in strongly interacting gases of highly excited Rydberg atoms where the facilitated excitation of Rydberg states competes with radiative decay. These systems approximately implement open quantum versions of models for population dynamics or disease spreading where species can be in a healthy, infected or immune state. We show that in a two-dimensional lattice, depending on the dominance of either classical or quantum effects, the system may display a different kind of nonequilibrium phase transition. We moreover discuss the observability of our findings in laser driven Rydberg gases with particular focus on the role of long-range interactions.
The Chernobyl psychological epidemic was already latent well prior to 1986 fully broke out after the accident, and continues to spread. It must be halted. But how can we counter a belief which has taken on the appearance of reality. It is the unknown, linked to alarming symbols, which sustains fear. To get beyond this state, radioactivity, ionizing radiation and nuclear energy have to become as ordinary as air travel and electronic calculators. In a climate of confidence and openness, it should be possible to successfully communicate several solid scientific reference points by first targeting teachers, doctors, and journalists. Thirty years ago, nuclear energy was presented as a universal panacea (clean, safe, and renewable). Now things have swung to the other extreme, and it is presented as diabolical. We have shifted from a symbolically white level to a symbolically black level, and both are misleading. It is high time to rejoin the world of facts, a world full of shades of gray
Witte, J J; Bigler, W J
Florida ranked fourth in the nation with 1,707 tuberculosis cases reported in 1992 for a rate of 12.7 per 100,000 population. Thirteen percent of these patients had AIDS. Recent cases in prisons, shelters, hospitals and schools have stimulated interest and media coverage. Resurgence of strains of multiple-drug resistant tuberculosis is a serious concern. The Florida Department of Health and Rehabilitative Services, in collaboration with allied agencies, has utilized several initiatives in response. The most significant, Tuberculosis Epidemic Containment Plan, details intervention strategies needed to eliminate TB in the state by the year 2010. Successful implementation depends upon local TB prevention and control coalitions that include private and public sector providers.
Aral, S O
Determinants of evolving epidemics of sexually transmitted diseases (STD) are equally influenced by the evolution of the STD epidemics themselves and by the evolution of human societies. A temporal approach to STD transmission dynamics suggests the need to monitor infectivity, rate of exposure between infected and susceptible individuals, and duration of infectiousness in societies. Different indicators may be used to monitor rate of exposure in the general population and in core groups. In addition, underlying determinants of STD epidemics such as poverty, inequality, racial/ethnic discrimination, unemployment, sex ratio, volume of migration, and health care coverage and quality are important variables to monitor through a surveillance system focused on social context. Ongoing large scale societal changes including urbanisation, globalisation, increasing inequality, and increasing volume of migrant populations may affect the evolution of STD epidemics. Globalised STD epidemics could pose a major challenge to local public health systems.
Ruan, Zhongyuan; Tang, Ming; Gu, Changgui; Xu, Jinshan
The structure of underlying contact network and the mobility of agents are two decisive factors for epidemic spreading in reality. Here, we study a model consisting of two coupled subpopulations with intra-structures that emphasizes both the contact structure and the recurrent mobility pattern of individuals simultaneously. We show that the coupling of the two subpopulations (via interconnections between them and round trips of individuals) makes the epidemic threshold in each subnetwork to be the same. Moreover, we find that the interconnection probability between two subpopulations and the travel rate are important factors for spreading dynamics. In particular, as a function of interconnection probability, the epidemic threshold in each subpopulation decreases monotonously, which enhances the risks of an epidemic. While the epidemic threshold displays a non-monotonic variation as travel rate increases. Moreover, the asymptotic infected density as a function of travel rate in each subpopulation behaves differently depending on the interconnection probability.
Huang, Shouying; Jiang, Jifa
In this paper, we develop and analyze an SIS epidemic model with a general nonlinear incidence rate, as well as degree-dependent birth and natural death, on heterogeneous networks. We analytically derive the epidemic threshold R0 which completely governs the disease dynamics: when R0 1, the disease is permanent. It is interesting that the threshold value R0 bears no relation to the functional form of the nonlinear incidence rate and degree-dependent birth. Furthermore, by applying an iteration scheme and the theory of cooperative system respectively, we obtain sufficient conditions under which the endemic equilibrium is globally asymptotically stable. Our results improve and generalize some known results. To illustrate the theoretical results, the corresponding numerical simulations are also given.
Gao Shujing; Chen Lansun; Sun Lihua
In most of population dynamics, increases in population due to birth are assumed to be time-dependent, but many species reproduce only during a single period of the year. In this paper, we propose an epidemic model with density-dependent birth pulses and seasonal prevention. Using the discrete dynamical system determined by stroboscopic map, we obtain the local or global stability, numerical simulation shows there is a characteristic sequence of bifurcations, leading to chaotic dynamics, which implies that the dynamical behaviors of the epidemic model with birth pulses and seasonal prevention are very complex, including small amplitude oscillations, large-amplitude multi-annual cycles and chaos. This suggests that birth pulse, in effect, provides a natural period or cyclicity that may lead a period-doubling route to chaos
Demirel, Rasime; Sen, Burhan; Kadaifciler, Duygu; Yoltas, Aysegul; Okten, Suzan; Ozkale, Evrim; Berikten, Derya; Samson, Robert A.; Haliki Uztan, Alev; Yilmaz, Neriman; Abaci Gunyar, Ozlem; Aydogdu, Halide; Asan, Ahmet; Kivanc, Merih; Ozdil, Soner; Sakartepe, Erhan
Pathogenic and/or opportunistic fungal species are major causes of nosocomial infections, especially in controlled environments where immunocompromised patients are hospitalized. Indoor fungal contamination in hospital air is associated with a wide range of adverse health effects. Regular
, chemical and drug industries. Since then, new fungal ...... Nesci A, Barros G, Castillo C, Etcheverry M (2006). Soil fungal population in preharvest maize ecosystem in different tillage practices in Argentina. Soil Tillage Res.
Shabalov, Igor; Grigoriev, Igor
MycoCosm is a web-based interactive fungal genomics resource, which was first released in March 2010, in response to an urgent call from the fungal community for integration of all fungal genomes and analytical tools in one place (Pan-fungal data resources meeting, Feb 21-22, 2010, Alexandria, VA). MycoCosm integrates genomics data and analysis tools to navigate through over 100 fungal genomes sequenced at JGI and elsewhere. This resource allows users to explore fungal genomes in the context of both genome-centric analysis and comparative genomics, and promotes user community participation in data submission, annotation and analysis. MycoCosm has over 4500 unique visitors/month or 35000+ visitors/year as well as hundreds of registered users contributing their data and expertise to this resource. Its scalable architecture allows significant expansion of the data expected from JGI Fungal Genomics Program, its users, and integration with external resources used by fungal community.
Joffe, Luna S.; Nimrichter, Leonardo; Rodrigues, Marcio L.; Del Poeta, Maurizio
ABSTRACT Extracellular vesicles (EVs) are produced by virtually all cell types. Within the past few years, work in this field has revealed more information about fungal EVs. Fungal EVs have been shown to carry proteins, lipids, pigments, polysaccharides, and RNA; these components are known virulence factors, a fact which supports the hypothesis that fungal EVs concentrate pathogenic determinants. Additionally, recent studies have demonstrated that fungal EVs stimulate the host immune system. ...
Boreal forests harbour diverse fungal communities with decisive roles in decomposition and plant nutrition. Difficulties in studying soil fungi have limited knowledge about how fungal communities are shaped. The objective of this thesis was to study factors influencing soil fungal communities, aiming for increased understanding of their effect on environmental processes. Using next generation sequencing, responses of fungal communities to their physical-chemical environment, and responses...
Loganathachetti, Dinesh Sanka; Poosakkannu, Anbu; Muthuraman, Sundararaman
The fungal communities of different soil compartments in mangrove ecosystem are poorly studied. We sequenced the internal transcribed spacer (ITS) regions to characterize the fungal communities in Avicennia marina root-associated soils (rhizosphere and pneumatophore) and bulk soil compartments. The rhizosphere but not pneumatophore soil compartment had significantly lower fungal species richness than bulk soil. However, bulk soil fungal diversity (Shannon diversity index) was significantly hi...
Rørtveit, S; Rortveit, G
Little is known about incidence and natural variation of impetigo in general populations. To investigate the natural course of impetigo in a well-defined population, and to study the resistance pattern of the causal bacteria over time. This is a population-based incidence study in Austevoll, an island community of 4457 inhabitants in Norway, in the years 2001-2005. Incidence rates are given as events per person-year. Epidemic periods were identified by statistical process-control analyses. The incidence rate of impetigo for the whole study period was 0.017 events per person-year, corresponding to a total of 334 cases. The incidence rates were 0.009, 0.026, 0.019, 0.016 and 0.009 in the years 2001, 2002, 2003, 2004 and 2005, respectively. Three epidemics were identified, starting in August of 2002, 2003 and 2004, lasting for 11, 11 and 5 weeks, respectively. Incidence rates in these epidemic periods were 0.099, 0.045 and 0.074, respectively. In epidemic periods, Staphylococcus aureus was the causal bacterium in 89% (117/132) of cases, while this proportion was 68% (84/123) in nonepidemic periods (P impetigo cases in epidemic and nonepidemic periods, respectively (P impetigo cases (152/201, 76%) differed significantly from fusidic acid resistance in other infections (18/116, 16%) (P < 0.01). Distinctive epidemic outbreaks occurred during the summer of three of the five follow-up years. In outbreaks, S. aureus was more frequently the causal agent and the sensitivity to fusidic acid decreased significantly.
Jessica L. Chitty
Full Text Available While members of the Kingdom Fungi are found across many of the world’s most hostile environments, only a limited number of species can thrive within the human host. The causative agents of the most common invasive fungal infections are Candida albicans, Aspergillus fumigatus, and Cryptococcus neoformans. During the infection process, these fungi must not only combat the host immune system while adapting to dramatic changes in temperature and pH, but also acquire sufficient nutrients to enable growth and dissemination in the host. One class of nutrients required by fungi, which is found in varying concentrations in their environmental niches and the human host, is the purines. These nitrogen-containing heterocycles are one of the most abundant organic molecules in nature and are required for roles as diverse as signal transduction, energy metabolism and DNA synthesis. The most common life-threatening fungal pathogens can degrade, salvage and synthesize de novo purines through a number of enzymatic steps that are conserved. While these enable them to adapt to the changing purine availability in the environment, only de novo purine biosynthesis is essential during infection and therefore an attractive antimycotic target.
Kunamneni, Adinarayana; Camarero, Susana; García-Burgos, Carlos; Plou, Francisco J; Ballesteros, Antonio; Alcalde, Miguel
Laccases are multi-copper containing oxidases (EC 126.96.36.199), widely distributed in fungi, higher plants and bacteria. Laccase catalyses the oxidation of phenols, polyphenols and anilines by one-electron abstraction, with the concomitant reduction of oxygen to water in a four-electron transfer process. In the presence of small redox mediators, laccase offers a broader repertory of oxidations including non-phenolic substrates. Hence, fungal laccases are considered as ideal green catalysts of great biotechnological impact due to their few requirements (they only require air, and they produce water as the only by-product) and their broad substrate specificity, including direct bioelectrocatalysis. Thus, laccases and/or laccase-mediator systems find potential applications in bioremediation, paper pulp bleaching, finishing of textiles, bio-fuel cells and more. Significantly, laccases can be used in organic synthesis, as they can perform exquisite transformations ranging from the oxidation of functional groups to the heteromolecular coupling for production of new antibiotics derivatives, or the catalysis of key steps in the synthesis of complex natural products. In this review, the application of fungal laccases and their engineering by rational design and directed evolution for organic synthesis purposes are discussed. PMID:19019256
Full Text Available Abstract Laccases are multi-copper containing oxidases (EC 188.8.131.52, widely distributed in fungi, higher plants and bacteria. Laccase catalyses the oxidation of phenols, polyphenols and anilines by one-electron abstraction, with the concomitant reduction of oxygen to water in a four-electron transfer process. In the presence of small redox mediators, laccase offers a broader repertory of oxidations including non-phenolic substrates. Hence, fungal laccases are considered as ideal green catalysts of great biotechnological impact due to their few requirements (they only require air, and they produce water as the only by-product and their broad substrate specificity, including direct bioelectrocatalysis. Thus, laccases and/or laccase-mediator systems find potential applications in bioremediation, paper pulp bleaching, finishing of textiles, bio-fuel cells and more. Significantly, laccases can be used in organic synthesis, as they can perform exquisite transformations ranging from the oxidation of functional groups to the heteromolecular coupling for production of new antibiotics derivatives, or the catalysis of key steps in the synthesis of complex natural products. In this review, the application of fungal laccases and their engineering by rational design and directed evolution for organic synthesis purposes are discussed.
Postolaky, O; Syrbu, T; Poiras, N; Baltsat, K; Maslobrod, S; Boortseva, S
Among natural factors that permanently influence on the plants, the soil microorganisms play a special role for the growing of plants as habitants of their rhizosphere. Mainly they are the representatives of actinomycetes genus Streptomyces and fungal genus Penicillium and their metabolic products stimulate plant growth and inhibit the growth of pathogenic fungi and bacteria. The aim of our study was to determine the antagonism of actinomycetes and micromycetes isolated from soils of R. Moldova against the fungal pathogens of agricultural plants. The strains were isolated from 5 types of chernozem (black soil) from central zone of R. Moldova, with different concentration of humus. Most of micromycetes and streptomycetes were isolated from soil sample 1 (monoculture of maize) and soil sample 2 (Poltava road border) with similar humus content (2.4-2.6%). The antifungal activity of micromycetes strains was occurring mostly against Fusarium solani and Thelaviopsis basicola, at streptomycetes against Alternaria alternata and Botrytis cinerea. It was revealed the strains completely inhibit the growth of Alt. alternata (streptomycetes strains 23, 33, 37), B. cinerea (Streptomyces sp. 17), and F. solani (Penicillium sp. 104). Our results allow to consider the actinomycetes Streptomyces sp.9, Streptomyces sp. 12, Streptomyces sp. 17, Streptomyces sp. 37 Streptomyces sp. 66 and micromycetes Penicillium sp. 5, Penicillium sp. 65, Penicillium sp. 104 isolated from soils of R. Moldova, as prospective strains-antagonists against the phytopathogenic fungus, the causative agents of agricultural plants deseasis.
Full Text Available Soil health, and the closely related terms of soil quality and fertility, is considered as one of the most important characteristics of soil ecosystems. The integrated approach to soil health assumes that soil is a living system and soil health results from the interaction between different processes and properties, with a strong effect on the activity of soil microbiota. All soils can be described using physical, chemical, and biological properties, but adaptation to environmental changes, driven by the processes of natural selection, are unique to the latter one. This mini review focuses on fungal biodiversity and its role in the health of managed soils as well as on the current methods used in soil mycobiome identification and utilization next generation sequencing (NGS approaches. The authors separately focus on agriculture and horticulture as well as grassland and forest ecosystems. Moreover, this mini review describes the effect of land-use on the biodiversity and succession of fungi. In conclusion, the authors recommend a shift from cataloging fungal species in different soil ecosystems toward a more global analysis based on functions and interactions between organisms.
Mueller-Loebnitz, Christoph; Ostermann, Helmut; Franzke, Anke; Loeffler, Juergen; Uharek, Lutz; Topp, Max; Einsele, Hermann
Patients with allogeneic stem cell transplantation (SCT) have a high risk of invasive fungal infections (IFIs) even after neutrophil regeneration. Immunological aspects might play a very important role in the IFI development in these patients. Some data are available supporting the identification of high-risk patients with IFI for example patients receiving stem cells from TLR4 haplotype S4 positive donors. Key defense mechanisms against IFI include the activation of neutrophils, the phagocytosis of germinating conidia by dendritic cells, and the fight of the cells of the innate immunity such as monocytes and natural killer cells against germlings and hyphae. Furthermore, immunosuppressive drugs interact with immune effector cells influencing the specific fungal immune defense and antimycotic drugs might interact with immune response. Based on the current knowledge on immunological mechanism in Aspergillus fumigatus, the first approaches of an immunotherapy using human T cells are in development. This might be an option for the future of aspergillosis patients having a poor prognosis with conventional treatment.
Full Text Available Patients with allogeneic stem cell transplantation (SCT have a high risk of invasive fungal infections (IFIs even after neutrophil regeneration. Immunological aspects might play a very important role in the IFI development in these patients. Some data are available supporting the identification of high-risk patients with IFI for example patients receiving stem cells from TLR4 haplotype S4 positive donors. Key defense mechanisms against IFI include the activation of neutrophils, the phagocytosis of germinating conidia by dendritic cells, and the fight of the cells of the innate immunity such as monocytes and natural killer cells against germlings and hyphae. Furthermore, immunosuppressive drugs interact with immune effector cells influencing the specific fungal immune defense and antimycotic drugs might interact with immune response. Based on the current knowledge on immunological mechanism in Aspergillus fumigatus, the first approaches of an immunotherapy using human T cells are in development. This might be an option for the future of aspergillosis patients having a poor prognosis with conventional treatment.
Wagener, Jeanette; Malireddi, R. K. Subbarao; Lenardon, Megan D.; Köberle, Martin; Vautier, Simon; MacCallum, Donna M.; Biedermann, Tilo; Schaller, Martin; Netea, Mihai G.; Kanneganti, Thirumala-Devi; Brown, Gordon D.; Brown, Alistair J. P.; Gow, Neil A. R.
Chitin is an essential structural polysaccharide of fungal pathogens and parasites, but its role in human immune responses remains largely unknown. It is the second most abundant polysaccharide in nature after cellulose and its derivatives today are widely used for medical and industrial purposes. We analysed the immunological properties of purified chitin particles derived from the opportunistic human fungal pathogen Candida albicans, which led to the selective secretion of the anti-inflammatory cytokine IL-10. We identified NOD2, TLR9 and the mannose receptor as essential fungal chitin-recognition receptors for the induction of this response. Chitin reduced LPS-induced inflammation in vivo and may therefore contribute to the resolution of the immune response once the pathogen has been defeated. Fungal chitin also induced eosinophilia in vivo, underpinning its ability to induce asthma. Polymorphisms in the identified chitin receptors, NOD2 and TLR9, predispose individuals to inflammatory conditions and dysregulated expression of chitinases and chitinase-like binding proteins, whose activity is essential to generate IL-10-inducing fungal chitin particles in vitro, have also been linked to inflammatory conditions and asthma. Chitin recognition is therefore critical for immune homeostasis and is likely to have a significant role in infectious and allergic disease. Authors Summary Chitin is the second most abundant polysaccharide in nature after cellulose and an essential component of the cell wall of all fungal pathogens. The discovery of human chitinases and chitinase-like binding proteins indicates that fungal chitin is recognised by cells of the human immune system, shaping the immune response towards the invading pathogen. We show that three immune cell receptors– the mannose receptor, NOD2 and TLR9 recognise chitin and act together to mediate an anti-inflammatory response via secretion of the cytokine IL-10. This mechanism may prevent inflammation-based damage
Mykrä, Heikki; Sarremejane, Romain; Laamanen, Tiina; Karjalainen, Satu Maaria; Markkola, Annamari; Lehtinen, Sirkku; Lehosmaa, Kaisa; Muotka, Timo
We examined how short-term (19 days) nutrient enrichment influences stream fungal and diatom communities, and rates of leaf decomposition and algal biomass accrual. We conducted a field experiment using slow-releasing nutrient pellets to increase nitrate (NO 3 -N) and phosphate (PO 4 -P) concentrations in a riffle section of six naturally acidic (naturally low pH due to catchment geology) and six circumneutral streams. Nutrient enrichment increased microbial decomposition rate on average by 14%, but the effect was significant only in naturally acidic streams. Nutrient enrichment also decreased richness and increased compositional variability of fungal communities in naturally acidic streams. Algal biomass increased in both stream types, but algal growth was overall very low. Diatom richness increased in response to nutrient addition by, but only in circumneutral streams. Our results suggest that primary producers and decomposers are differentially affected by nutrient enrichment and that their responses to excess nutrients are context dependent, with a potentially stronger response of detrital processes and fungal communities in naturally acidic streams than in less selective environments.
Tayel, Ahmed A; Ibrahim, Sami I A; Al-Saman, Mahmoud A; Moussa, Shaaban H
Raw and processed meat contaminated with pathogenic microorganisms is a continuing worldwide problem facing health and industry overseers. Fungal chitosan was extracted, purified and characterized from Aspergillus brasiliensis (niger) ATCC 16404 grown in date syrup (dips) and applied as a potential meat biopreservative. The main features of produced chitosan were a deacetylation degree of 81.3%, a molecular weight of 31,000Da, 96% solubility in 1% acetic acid solution and a harmonized IR-spectrum to standard commercial chitosan. The application of fungal chitosan, as a natural and safe biopreservative for minced meat, was conducted in comparison with potassium sorbate, as a commercial meat preservative. Treated meat samples with 0.02% chitosan was the least trials in microbial contents, i.e. total count, coliforms, β-glucuronidase-positive Escherichia coli, Enterobacteriaceae, yeasts and molds, Staphylococcus aureus and coagulase positive staphylococci. The antimicrobial activity of fungal chitosan was considerably greater than that of potassium sorbate or their combination at 0.01% from each. Sensory characteristics, e.g. color, odor and texture, of treated meat with chitosan, were higher than those of control and potassium sorbate treated samples. Fungal chitosan, however, could be recommended as a powerful, natural and eco-friendly alternative for meat preservation and overall quality maintenance. Copyright © 2014 Elsevier B.V. All rights reserved.
This podcast gives an overview of the October 2012 multistate fungal meningitis outbreak, including symptoms to watch for and a website for up-to-date information. Created: 10/17/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 10/17/2012.
Almeida, Mariana Cruz; Brand, Alexandra C
The growth and development of most fungi take place on a two-dimensional surface or within a three-dimensional matrix. The fungal sense of touch is therefore critical for fungi in the interpretation of their environment and often signals the switch to a new developmental state. Contact sensing, or thigmo-based responses, include thigmo differentiation, such as the induction of invasion structures by plant pathogens in response to topography; thigmonasty, where contact with a motile prey rapidly triggers its capture; and thigmotropism, where the direction of hyphal growth is guided by physical features in the environment. Like plants and some bacteria, fungi grow as walled cells. Despite the well-demonstrated importance of thigmo responses in numerous stages of fungal growth and development, it is not known how fungal cells sense contact through the relatively rigid structure of the cell wall. However, while sensing mechanisms at the molecular level are not entirely understood, the downstream signaling pathways that are activated by contact sensing are being elucidated. In the majority of cases, the response to contact is complemented by chemical cues and both are required, either sequentially or simultaneously, to elicit normal developmental responses. The importance of a sense of touch in the lifestyles and development of diverse fungi is highlighted in this review, and the candidate molecular mechanisms that may be involved in fungal contact sensing are discussed.
Roden, Anja C; Schuetz, Audrey N
Fungal pneumonias can be a diagnostic problem. However, their recognition is important as they can pose a significant health risk, especially in the immunocompromised host. While many of these infections are accompanied by necrotizing or non-necrotizing granulomas, some might be characterized by cellular interstitial pneumonia, intra-alveolar frothy material or only minimal inflammatory change. Much of the tissue reaction is dependent on the immune status of the patient and the type of fungal organism. While many of the fungi can be identified in tissue, especially if using histochemical stains such as Grocott's Methenamine Silver (GMS) stain and/or Periodic Acid Schiff (PAS) stain, in some cases, these stains are negative and the organisms can only be identified in cultures or using special techniques such as PCR or fungal serology. Some fungi can be accurately identified in tissue based on morphologic features; others require culture for exact classification. Knowledge about immune status, geographic region and social history of the patient are helpful in identifying the fungus and, therefore, detailed clinical and travel histories are important. In this manuscript we aim to describe the most common fungal infections that occur in the lung, their morphologic features, and differential diagnoses. Copyright © 2017 Elsevier Inc. All rights reserved.
The invention provides isolated fungal endophytes and synthetic combinations thereof with host grass plants. Methods for inoculating grass plant with the endophytes, for propagating the grass-endophyte combinations, and for producing feeds and biofuels from grass-endophyte combinations are also provided.
Crous, P.W.; Wingfield, M. J.; Richardson, D. M.; Le Roux, J. J.; Strasberg, D.; Edwards, J.; Roets, F.; Hubka, V.; Taylor, P.W.J.; Heykoop, M.; Martín, M.P.; Moreno, G.; Sutton, D.A.; Wiederhold, N.P.; Barnes, C.W.; Carlavilla, J.R.; Gené, J.; Giraldo, A.; Guarnaccia, V.; Guarro, J.; Hernández-Restrepo, M.; Kolařík, Miroslav; Manjón, J.L.; Pascoe, I.G.; Popov, E.S.; Sandoval-Denis, M.; Woudenberg, J.H.C.; Acharya, K.; Alexandrova, A.V.; Alvarado, P.; Barbosa, R.N.; Baseia, I.G.; Blanchette, R.A.; Boekhout, T.; Burgess, T.I.; Cano-Lira, J.F.; Čmoková, A.; Dimitrov, R.A.; Dyakov, M.Yu.; Dueñas, M.; Dutta, A.K.; Esteve- Raventós, F.; Fedosova, A.G.; Fournier, J.; Gamboa, P.; Gouliamova, D.E.; Grebenc, T.; Groenewald, M.; Hanse, B.; Hardy, G.E.St.J.; Held, B.W.; Jurjević, Ž.; Kaewgrajang, T.; Latha, K.P.D.; Lombard, L.; Luangsa-Ard, J.J.; Lysková, P.; Mallátová, N.; Manimohan, P.; Miller, A.N.; Mirabolfathy, M.; Morozova, O.V.; Obodai, M.; Oliveira, N.T.; Otto, E.C.; Paloi, S.; Peterson, S.W.; Phosri, C.; Roux, J.; Salazar, W.A.; Sánchez, A.; Sarria, G.A.; Shin, H.-D.; Silva, B.D.B.; Silva, G.A.; Smith, M.Th.; Souza-Motta, C.M.; Stchigel, A.M.; Stoilova-Disheva, M.M.; Sulzbacher, M.A.; Telleria, M.T.; Toapanta, C.; Traba, J.M.; Valenzuela-Lopez, N.; Watling, R.; Groenewald, J.Z.
Roč. 36, July (2016), s. 316-458 ISSN 0031-5850 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : ITS DNA barcodes * LSU * fungal species Subject RIV: EE - Microbiology, Virology Impact factor: 7.511, year: 2016
Bolton, M.D.; Thomma, B.P.H.J.
Over the course of evolution, fungi have adapted to occupy specific niches, from symbiotically inhabiting the flora of the intestinal tract of mammals to saprophytic growth on leaf litter resting on the forest floor. In Plant Fungal Pathogens: Methods and Protocols, expert researchers in the field
Jensen, Annette Bruun; Aronstein, Kathrine; Manuel Flores, Jose
Chalkbrood and stonebrood are two fungal diseases associated with honey bee brood. Chalkbrood, caused by Ascosphaera apis, is a common and widespread disease that can result in severe reduction of emerging worker bees and thus overall colony productivity. Stonebrood is caused by Aspergillus spp. ...
The domesticated apple (Malus domestica) is the most significant pome fruit grown and consumed worldwide. China is the largest producer followed by the United States on a global scale. However, fungal plant pathogens cause significant economic losses in the field and in storage which negatively impa...
Yarden, O.; Ebbole, D.J.; Freeman, S.; Rodriguez, R.J.; Dickman, M. B.
Plant pathology has made significant progress over the years, a process that involved overcoming a variety of conceptual and technological hurdles. Descriptive mycology and the advent of chemical plant-disease management have been followed by biochemical and physiological studies of fungi and their hosts. The later establishment of biochemical genetics along with the introduction of DNA-mediated transformation have set the stage for dissection of gene function and advances in our understanding of fungal cell biology and plant-fungus interactions. Currently, with the advent of high-throughput technologies, we have the capacity to acquire vast data sets that have direct relevance to the numerous subdisciplines within fungal biology and pathology. These data provide unique opportunities for basic research and for engineering solutions to important agricultural problems. However, we also are faced with the challenge of data organization and mining to analyze the relationships between fungal and plant genomes and to elucidate the physiological function of pertinent DNA sequences. We present our perspective of fungal biology and agriculture, including administrative and political challenges to plant protection research.
Crous, Pedro W; Schumacher, René K; Wingfield, Michael J; Lombard, Lorenzo; Giraldo, Alejandra; Christensen, Martha; Gardiennet, Alain; Nakashima, Chiharu; Pereira, Olinto L; Smith, Alexander J; Groenewald, Johannes Z
Fungal Systematics and Evolution (FUSE) is introduced as a new series to expedite the publication of issues relating to the epitypification of formerly described species, report new sexual-asexual connections, the merging of sexual and asexual gen¬era following the end of dual nomenclature, and to
Hawksworth, D.L.; Crous, P.W.; Redhead, S.A.; Reynolds, D.R.; Samson, R.A.; Seifert, K.A.; Taylor, J.E.; Wingfield, M.J.; Abaci, Ö.; Aime, C.; Asan, A.; Bai, F.H.; de Beer, Z.W.; Begerow, D.; Berikten, D.; Boekhout, T.; Buchanan, P.K.; Burgess, T.I.; Buzina, W.; Cai, L.; Cannon, P.F.; Crane, J.L.; Damm, U.; Daniel, H.M.; van Diepeningen, A.D.; Druzhinina, I.; Dyer, P.S.; Eberhardt, U.; Fell, J.W.; Frisvad, J.C.; Geiser, D.M.; Geml, J.; Glienke, C.; Gräfenhan, T.; Groenewald, J.Z.; Groenewald, M.; de Gruyter, J.; Guého-Kellermann, E.; Guo, L-D.; Hibbett, D.S.; Hong, S.B.; de Hoog, G.S.; Houbraken, J.; Huhndorf, S.M.; Hyde, K.D.; Ismail, A.; Johnston, P.R.; Kadaifciler, D.G.; Kirk, P.M.; Kõljalg, U.; Kurtzman, C.P.; Lagneau, P-E.; Lévesque, C.A.; Liu, X.S.; Lombard, L.; Meyer, W.; Miller, A.N.; Minter, D.W.; Najafzadeh, M.J.; Norvell, L.L.; Ozerskaya, S.M.; Öziç, R.; Pennycook, S.R.; Peterson, S.W.; Pettersson, O.V.; Quaedvlieg, W.; Robert, V.; Ruibal, C.; Schnürer, J.; Schroers, H.J.; Shivas, R.G.; Slippers, B.; Spierenburg, H.; Takashima, M.; Taşkın, E.; Thines, M.; Thrane, U.; Uztan, A.H.; van Raak, M.; Varga, J.; Vasco, A.; Verkley, G.J.M.; Videira, S.I.R.; de Vries, R.P.; Weir, B.S.; Yilmaz, N.; Yurkov, A.; Zhang, N.
The Amsterdam Declaration on Fungal Nomenclature was agreed at an international symposium convened in Amsterdam on 19-20 April 2011 under the auspices of the International Commission on the Taxonomy of Fungi (ICTF). The purpose of the symposium was to address the issue of whether or how the current
Allan, E.; Ruijven, van J.; Crawley, M.J.
By attacking plants, herbivorous mammals, insects, and belowground pathogens are known to play an important role in maintaining biodiversity in grasslands. Foliar fungal pathogens are ubiquitous in grassland ecosystems, but little is known about their role as drivers of community composition and
Raaijmakers, R.; Schroder, C.; Monnens, L.A.H.; Cornelissen, E.A.M.; Warris, A.
Fungal peritonitis is a rare but serious complication in children on peritoneal dialysis (PD). In this study, risk factors were evaluated, and therapeutic measures were reviewed. A retrospective, multi-centre study was performed in 159 Dutch paediatric PD patients, between 1980 and 2005 (3,573
Kenneth E. Hammel; Dan Cullen
The degradation of lignin by filamentous fungi is a major route for the recycling of photosynthetically fixed carbon, and the oxidative mechanisms employed have potential biotechnological applications. The lignin peroxidases (LiPs), manganese peroxidases (MnPs), and closely related enzymes of white rot basidiomycetes are likely contributors to fungal ligninolysis. Many...
Full Text Available The presence and association of fungi with sessile marine animals such as coral and sponges has been well established, yet information on the extent of diversity of the associated fungi is still in its infancy. Culture- as well as metagenomic- and transcriptomic-based analyses have shown that fungal presence in association with these animals can be dynamic and can include core residents as well as shifts in fungal communities. Evidence for detrimental and beneficial interactions between fungi and their marine hosts is accumulating and current challenges include the elucidation of the chemical and cellular crosstalk between fungi and their associates within the holobionts. The ecological function of fungi in association with sessile marine animals is complex and is founded on a combination of factors such as fungal origin, host health, environmental conditions and the presence of other resident or invasive microorganisms in the host. Based on evidence from the much more studied terrestrial systems, the evaluation of marine animal-fungal symbioses under varying environmental conditions may well prove to be critical in predicting ecosystem response to global change, including effects on the health of sessile marine animals.
Albæk, Mads Orla; Gernaey, Krist; Hansen, Morten S.
We have developed a process model of fungal fed-batch fermentations for enzyme production. In these processes, oxygen transfer rate is limiting and controls the substrate feeding rate. The model has been shown to describe cultivations of both Aspergillus oryzae and Trichoderma reesei strains in 550...
Droce, Aida; Sørensen, Jens Laurids; Giese, Henriette
Transcription of various bioactive compounds and enzymes are dependent on fungal cultivation method. In this study we cultivate Fusarium graminearum and Fusarium solani on glass-beads with liquid media in petri dishes as an easy and inexpensive cultivation method, that resembles in secondary...
Batac, M C R; Denning, D
The Philippines is a low middle-income, tropical country in Southeast Asia. Infectious diseases remain the main causes of morbidity, including tuberculosis. AIDS/HIV prevalence is still low at Philippine Health Statistics 2011, Philippine Dermatological Society Health Information System database, HIV/AIDS and ART registry of the Philippines, epidemiological studies such as The TREAT Asia HIV Observational Database 2005, and personal communication. Aspergillosis and candidiasis were the top causes of fungal infections in the Philippines. Chronic pulmonary aspergillosis (CPA), drawn from the number of tuberculosis patients, affects 77,172 people. Allergic bronchopulmonary aspergillosis (ABPA) and severe asthma with fungal sensitization (SAFS) frequencies, which were derived from the number of asthmatic patients, affect 121,113 and 159,869 respectively. Recurrent vulvovaginal candidiasis (RVVC) affects 1,481,899 women. Other estimates were cryptococcal meningitis 84, Pneumocystis pneumonia 391, oral candidiasis 3,467, esophageal candidiasis 1,522 (all in HIV-infected people), invasive aspergillosis (IA) 3,085, candidemia 1,968, candida peritonitis 246, mucormycosis 20, fungal keratitis 358, tinea capitis 846 and mycetoma 97 annually. A total of 1,852,137 (1.9% of population) are afflicted with a serious fungal infection. Epidemiological studies are needed to validate these estimates, facilitating appropriate medical care of patients and proper prioritization of limited resources.
Nielsen, Per Væggemose; Haasum, Iben
Fungal contamination is one of the most important quality deteriorating factors on cheese. During the last 5 years we have studied in detail the underlying factors controlling these unwanted processes in a collaborative project financed by the Danish Dairy Board and the Ministry of Agriculture. R...
Crous, P. W.; Wingfield, M. J.; Le Roux, J. J.; Richardson, D. M.; Strasberg, D.; Shivas, R.G.; Alvarado, P.; Edwards, J.; Moreno, G.; Sharma, R.; Sonawane, M.S.; Tan, Y.P.; Altés, A.; Barasubiye, T.; Barnes, C.W.; Blanchette, R.A.; Boertmann, D.; Bogo, A.; Carlavilla, J.R.; Cheewangkoon, R.; Daniel, R.; de Beer, Z.W.; de Yáňez-Morales, J.; Duong, T.A.; Fernández-Vicente, J.; Geering, A.D.W.; Guest, D.I.; Held, B.W.; Heykoop, M.; Hubka, V.; Ismail, A.M.; Kajale, S.C.; Khemmuk, W.; Kolařík, Miroslav; Kurli, R.; Lebeuf, R.; Levesque, C.A.; Lombard, L.; Magista, D.; Manjón, J.L.; Marincowitz, S.; Mohedano, J.M.; Nováková, Alena; Oberlies, N.H.; Otto, E.C.; Paguigan, N.D.; Pascoe, I.G.; Peréz-Butrón, J.L.; Perrone, G.; Rahi, P.; Raja, H.A.; Rintoul, T.; Sanhueza, R.M.V.; Scarlett, K.; Shouche, Y.S.; Shuttleworth, L.A.; Taylor, P.W.J.; Thorn, R.G.; Vawdrey, L.L.; Solano-Vidal, R.; Voitk, A.; Wong, P.T.W.; Wood, A.R.; Zamora, J.C.; Groenewald, J.Z.
Roč. 35, December (2015), s. 264-327 ISSN 0031-5850 R&D Projects: GA ČR(CZ) GAP506/12/1064 Institutional support: RVO:61388971 Keywords : ITS DNA barcodes * LSU * novel fungal species Subject RIV: EE - Microbiology, Virology Impact factor: 5.725, year: 2015
Paula Monteiro de Souza
Full Text Available Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications.
de Souza, Paula Monteiro; Bittencourt, Mona Lisa de Assis; Caprara, Carolina Canielles; de Freitas, Marcela; de Almeida, Renata Paula Coppini; Silveira, Dâmaris; Fonseca, Yris Maria; Ferreira, Edivaldo Ximenes; Pessoa, Adalberto; Magalhães, Pérola Oliveira
Proteases hydrolyze the peptide bonds of proteins into peptides and amino acids, being found in all living organisms, and are essential for cell growth and differentiation. Proteolytic enzymes have potential application in a wide number of industrial processes such as food, laundry detergent and pharmaceutical. Proteases from microbial sources have dominated applications in industrial sectors. Fungal proteases are used for hydrolyzing protein and other components of soy beans and wheat in soy sauce production. Proteases can be produced in large quantities in a short time by established methods of fermentation. The parameters such as variation in C/N ratio, presence of some sugars, besides several other physical factors are important in the development of fermentation process. Proteases of fungal origin can be produced cost effectively, have an advantage faster production, the ease with which the enzymes can be modified and mycelium can be easily removed by filtration. The production of proteases has been carried out using submerged fermentation, but conditions in solid state fermentation lead to several potential advantages for the production of fungal enzymes. This review focuses on the production of fungal proteases, their distribution, structural-functional aspects, physical and chemical parameters, and the use of these enzymes in industrial applications. PMID:26273247
J. P. Schmit; D. J. Lodge
In this chapter, we examine the use of classical methods to study fungal diversity. Classical methods rely on the direct observation of fungi, rather than sampling fungal DNA. We summarize a wide variety of classical methods, including direct sampling of fungal fruiting bodies, incubation of substrata in moist chambers, culturing of endophytes, and particle plating. We...
Chen, Yingxin; Yang, Weijia; Gao, Minghong; Belin, Michael Wellington; Yu, Hai; Yu, Jing
Fungal corneal ulcer is one of the major causes of visual impairment worldwide. Treatment of fungal corneal ulcer mainly depends on anti-fungal agents. In the current study, we developed an integrated combination therapy of cryotherapy and anti-fungal agents to facilitate effective treatment of fungal corneal ulcer. Rabbit models of cornea infection were established using a combined method of intrastromal injection and keratoplasty. After treatment with cryotherapy and anti-fungal agents, scanning electron microscopy, transmission electron microscopy, and confocal microscopy were conducted to observe changes in microstructure in the rabbits. Periodic acid Schiff A and hematoxylin and eosin staining were used for detection of histological changes. Continuous scanning electron microscopy and transmission electron microscopy observations showed that cryothermal treatment inhibited growth of fungal mycelium by destroying fungal cellular structures. Typical cryotherapy was effective in curing fungal corneal ulcer. Different fungi showed different susceptibilities to treatment. The curative effect of Candida albicans was the best, while that of Aspergillus fumigates was the worst. Our study provides a novel method of a combination of cryotherapy and anti-fungal agents for treatment of fungal corneal ulcer. This treatment could help facilitate the practice of fungal keratitis treatment in the future.
Full Text Available Objective: To estimate the burden of fungal infections in Jordan for the first time. Material and Methods: Population data was from UN 2011 statistics and TB cases from WHO in 2012. Fewer than 100 patients with HIV were recorded in Jordan in 2013. Approximately 100 renal transplants and eight liver transplants are performed annually. There were 12,233 major surgical procedures in Jordan in 2013, of which 5.3% were major abdominal surgeries; candidemia was estimated in 5% of the population based on other countries, with 33% occurring in the ICU. Candida peritonitis/intra-abdominal candidiasis was estimated to affect 50% of the number of ICU candidemia cases. No adult asthma rates have been recorded for Jordan, so the rate from the Holy Land (8.54% clinical asthma from To et al. has been used. There are an estimated 49,607 chronic obstructive pulmonary disease (COPD patients in Jordan, with 64% symptomatic, 25% Gold stage 3% or 4%, and 7% (3472 are assumed to be admitted to hospital each year. No cystic fibrosis cases have been recorded. Literature searches on fungal infections revealed few data and no prevalence data on fungal keratitis or tinea capitis, even though tinea capitis comprised 34% of patients with dermatophytoses in Jordan. Results: Jordan has 6.3 million inhabitants (65% adults, 6% are >60 years old. The current burden of serious fungal infections in Jordan was estimated to affect ~119,000 patients (1.9%, not including any cutaneous fungal infections. Candidemia was estimated at 316 cases and invasive aspergillosis in leukemia, transplant, and COPD patients at 84 cases. Chronic pulmonary aspergillosis prevalence was estimated to affect 36 post-TB patients, and 175 in total. Allergic bronchopulmonary aspergillosis (ABPA and severe asthma with fungal sensitization (SAFS prevalence in adults with asthma were estimated at 8900 and 11,748 patients. Recurrent vulvovaginal candidiasis was estimated to affect 97,804 patients, using a 6
Thahim, K.; Jawaid, M.A.; Marfani, S.
To assess the presentation of allergic fungal sinusitis and describe the line of management in our setup. Culture and sensitivity / fungal stain proven 20 cases of allergic fungal sinusitis were selected for the study, irrespective of age and gender. Data including age, gender, socioeconomic status, signs, symptoms, laboratory findings (especially Immunoglobulin E and eosinophil count) and imaging studies (Computed Tomography and /or Magnetic Resonance Imaging) were noted for the study. Pre and postoperative medical treatment, surgery performed, follow-up; residual/recurrence disease and revised surgery performed were also recorded. In this series, allergic fungal sinusitis was a disease of younger age group with an average age of 20.75 years with male dominance (70%). Poor socioeconomic status (80%), allergic rhinitis (100%) and nasal polyposis (100%) were important associated factors. Nasal obstruction (100%), nasal discharge (90%), postnasal drip (90%) and unilateral nasal and paranasal sinuses involvement (60%) were the commonest presenting features. Aspergillus (60%) was the most common etiological agent. In all cases (100%), increased eosinophil count and IgE levels were present. Orbital (20%) and intracranial (10%) involvement were also seen. Surgical management was preferred in all cases. Functional endoscopic sinus surgery in 90% cases and lateral rhinotomy in 10% cases were performed. Recurrence / residual disease was seen in 20% cases. In this series, allergic fungal sinusitis was seen in immunocompetent, young males, belonging to poor socioeconomic status, suffering from allergic rhinitis and nasal polyposis, presenting with nasal obstruction, nasal discharge and postnasal drip. Functional endoscopic sinus surgery was the most important problem solving procedure while lateral rhinotomy was reserved for extensive disease. (author)
Andargie, Mebeaselassie; Congyi, Zhu; Yun, Yun; Li, Jianxiong
False smut disease of rice is posing an increasing concern for production, not only because of the hiking epidemic occurrence in rice production, but also because of the challenging specific pathogenesis of the disease. The aim of this work was to evaluate the potential of five fungal endophytes to reduce negative effects of rice false smut fungus (Ustilagonoidea virens) on rice plants, in both the laboratory and greenhouse. Though all the fungal isolates showed the ability to inhibit the growth of U. virens with varying degrees, isolate E337 showed significant antagonistic activity against the pathogenic fungi. The isolate E337 was identified as Antennariella placitae by molecular and morphological data analysis including 18S rDNA sequence analysis. This isolate showed a significant in vitro inhibition of mycelial growth of U. virens by dual culture method and it was subsequently tested for its in vivo biocontrol potential on false smut disease on rice plants. Greenhouse experiments confirmed that applications of conidia of A. placitae protected rice plants by improving rice yield and by decreasing the severity of false smut disease on susceptible rice plants. This is the first report where A. placitae has been identified as a biocontrol organism.
Vittal, R; Paul, C; Hill, C B; Hartman, G L
Soybean rust, caused by the fungus Phakopsora pachyrhizi, is an economically important disease of soybean with potential to cause severe epidemics resulting in significant yield losses. Host resistance is one of the management tools to control this disease. This study compared soybean genotypes exhibiting immunity, complete and incomplete resistance, and susceptibility to an isolate of P. pachyrhizi based on visual assessment of reaction type, other visual traits such as sporulation, quantitative measurements of the amount of fungal DNA (FDNA) present in leaf tissues, and data on infection and colonization levels. Soybean genotype UG5 (immune), and plant introduction (PI) 567102B and PI 567104B (complete resistance) had lower quantities of uredinia and FDNA than four other genotypes with incomplete resistance. Based on microscopic observations, early events of spore germination, appressorium formation, and fungal penetration of the epidermis occurred within 24 h postinoculation and were similar among the tested soybean genotypes. Differences in infection among the genotypes were evident once the hyphae penetrated into the intercellular spaces between the mesophyll cells. At 2 days after inoculation (dai), soybean genotype Williams 82 had a significantly (P pachyrhizi interaction results in restricted hyphal development in mesophyll cell tissue, likely due to hypersensitive apoptosis.
Ouellette, G. B.; Baayen, R. P.; Chamberland, H.; Simard, M.; Rioux, D.; Charest, P. M.
Antibodies to detect pectin in present investigations attached to distinct fibrils in vessel lumina. In carnation infected with an isolate of Fusarium oxysporum f.sp., labeling of pathogen cells also occurred; in a resistant cultivar (cv.), it was coincident with proximate pectin fibrils and linked to altered fungal walls, which was the opposite in the susceptible cv., indicating that hindrance of pathogen ability to degrade pectin may be related to resistance. Labeling of the fungus in culture was nil, except in media containing pectin, showing that pectin is not native to the pathogen. Labeling of fungal walls for cellulose in elm (inoculated with Ophiostoma novo-ulmi) and carnation also occurred, linked to adsorbed host wall components. The chitin probe often attached to dispersed matter, in vessel lumina, traceable to irregularly labeled fungal cells and host wall degradation products. With an anti-horseradish peroxidase probe, host and fungal walls were equally labeled, and with a glucosidase, differences of labeling between these walls were observed, depending on pH of the test solution. Fungal extracellular matter and filamentous structures, present in fungal walls, predominantly in another elm isolate (Phaeotheca dimorphospora), did not label with any of the probes used. However, in cultures of this fungus, extracellular material labeled, even at a distance from the colony margin, with an anti-fimbriae probe.
You, Young-Hyun; Yoon, Hyeokjun; Kang, Sang-Mo; Shin, Jae-Ho; Choo, Yeon-Sik; Lee, In-Jung; Lee, Jin-Man; Kim, Jong-Guk
Endophytic fungi were isolated from roots of six halophytes in Suncheon Bay. The endophytic fungi of 35 species isolated from halophytes were identified by internal transcribed spacer (ITS) containing the ITS1, 5.8s, and ITS2 regions. All fungal strains were analyzed to diversity at the genus level. Fungal culture filtrates (FCF) of endophytic fungi were treated to Waito-c rice (WR) seedling for plant growth-promoting verification. It was confirmed that fungal strain Sj-2-2 provided plant growth promotion (PGP) to WR seedling. Then, PGP of Suaeda japonica was confirmed by treating culture filtrate of Sj-2-2. As a result, it was verified that culture filtrate of Sj-2-2 had more advanced PGP than positive control when treated to S. japonica. The secondary metabolites involved in culture filtrate of Sj-2-2 were identified by HPLC and GC-MS SIM analysis. The presence of physiologically bioactive gibberellins (GAs) and other inactive GAs in culture filtrate of Sj-2-2 was detected. The molecular analysis of sequences of Sj-2-2 showed the similarity to Penicillium sp. of 99% homology. The PGP of Sj-2-2 as well as symbiosis between endophytic fungi and halophytes growing naturally in salt marsh was confirmed. Sj-2-2 was identified as a new fungal strain producing GAs by molecular analysis of sequences. Consequently, the Sj-2-2 fungal strain was named as Penicillium sp. Sj-2-2. In this study, the diversity of endophytic fungi isolated from roots of halophytes in salt marsh and the PGP of a new gibberellin-producing fungal strain were confirmed.
Nagano, Yuriko; Miura, Toshiko; Nishi, Shinro; Lima, Andre O.; Nakayama, Cristina; Pellizari, Vivian H.; Fujikura, Katsunori
We investigated the fungal diversity in a total of 20 deep-sea sediment samples (of which 14 samples were associated with natural asphalt seeps and 6 samples were not associated) collected from two different sites at the Sao Paulo Plateau off Brazil by Ion Torrent PGM targeting ITS region of ribosomal RNA. Our results suggest that diverse fungi (113 operational taxonomic units (OTUs) based on clustering at 97% sequence similarity assigned into 9 classes and 31 genus) are present in deep-sea sediment samples collected at the Sao Paulo Plateau, dominated by Ascomycota (74.3%), followed by Basidiomycota (11.5%), unidentified fungi (7.1%), and sequences with no affiliation to any organisms in the public database (7.1%). However, it was revealed that only three species, namely Penicillium sp., Cadophora malorum and Rhodosporidium diobovatum, were dominant, with the majority of OTUs remaining a minor community. Unexpectedly, there was no significant difference in major fungal community structure between the asphalt seep and non-asphalt seep sites, despite the presence of mass hydrocarbon deposits and the high amount of macro organisms surrounding the asphalt seeps. However, there were some differences in the minor fungal communities, with possible asphalt degrading fungi present specifically in the asphalt seep sites. In contrast, some differences were found between the two different sampling sites. Classification of OTUs revealed that only 47 (41.6%) fungal OTUs exhibited >97% sequence similarity, in comparison with pre-existing ITS sequences in public databases, indicating that a majority of deep-sea inhabiting fungal taxa still remain undescribed. Although our knowledge on fungi and their role in deep-sea environments is still limited and scarce, this study increases our understanding of fungal diversity and community structure in deep-sea environments.
Brightwell, Graham; House, Thomas; Luczak, Malwina
Many real epidemics of an infectious disease are not straightforwardly super- or sub-critical, and the understanding of epidemic models that exhibit such complexity has been identified as a priority for theoretical work. We provide insights into the near-critical regime by considering the stochastic SIS logistic epidemic, a well-known birth-and-death chain used to model the spread of an epidemic within a population of a given size N. We study the behaviour of the process as the population size N tends to infinity. Our results cover the entire subcritical regime, including the "barely subcritical" regime, where the recovery rate exceeds the infection rate by an amount that tends to 0 as [Formula: see text] but more slowly than [Formula: see text]. We derive precise asymptotics for the distribution of the extinction time and the total number of cases throughout the subcritical regime, give a detailed description of the course of the epidemic, and compare to numerical results for a range of parameter values. We hypothesise that features of the course of the epidemic will be seen in a wide class of other epidemic models, and we use real data to provide some tentative and preliminary support for this theory.
Hurt, Ryan T; Frazier, Thomas H; McClave, Stephen A; Kaplan, Lee M
Obesity is one of the leading causes of preventable death in the United States, second only to smoking. The annual number of deaths attributed to obesity is estimated to be as high as 400,000. Nearly 70% of the adult U.S. population is overweight or obese. The historical viewpoint toward obesity has deemed it to be a lifestyle choice or characterological flaw. However, given the emerging research into the development of obesity and its related complications, our perspective is changing. It is now clear that obesity is a heterogeneous disease with many different subtypes, which involves an interplay between genetic and environmental factors. The current epidemic of obesity is the result of an obesogenic environment (which includes energy-dense foods and a lack of physical activity) in individuals who have a genetic susceptibility for developing obesity. The pathophysiology associated with weight gain is much more complex than originally thought. The heterogeneous nature of the disease makes the development of treatment strategies for obesity difficult. Obesity in general is associated with increased all-cause mortality and cause-specific mortality (from cardiovascular, diabetic, hepatic, and neoplastic causes). Yet despite increased overall mortality rates, current evidence suggests that when these same patients are admitted to the intensive care unit (ICU), the obesity provides some protection against mortality. At present, there is no clear explanation for this obesity conundrum in critical illness.
Daniel L. Lindner; Rimvydas Vasaitis; Ariana Kubartova; Johan Allmer; Hanna Johannesson; Mark T. Banik; Jan. Stenlid
Picea abies logs were inoculated with Resinicium bicolor, Fomitopsis pinicola or left un-inoculated and placed in an old-growth boreal forest. Mass loss and fungal community data were collected after 6 yr to test whether simplification of the fungal community via inoculation affects mass loss and fungal community development. Three...
Séne, Seynabou; Avril, Raymond; Chaintreuil, Clémence; Geoffroy, Alexandre; Ndiaye, Cheikh; Diédhiou, Abdala Gamby; Sadio, Oumar; Courtecuisse, Régis; Sylla, Samba Ndao; Selosse, Marc-André; Bâ, Amadou
We studied belowground and aboveground diversity and distribution of ectomycorrhizal (EM) fungal species colonizing Coccoloba uvifera (L.) L. (seagrape) mature trees and seedlings naturally regenerating in four littoral forests of the Guadeloupe island (Lesser Antilles). We collected 546 sporocarps, 49 sclerotia, and morphotyped 26,722 root tips from mature trees and seedlings. Seven EM fungal species only were recovered among sporocarps (Cantharellus cinnabarinus, Amanita arenicola, Russula cremeolilacina, Inocybe littoralis, Inocybe xerophytica, Melanogaster sp., and Scleroderma bermudense) and one EM fungal species from sclerotia (Cenococcum geophilum). After internal transcribed spacer (ITS) sequencing, the EM root tips fell into 15 EM fungal taxa including 14 basidiomycetes and 1 ascomycete identified. Sporocarp survey only weakly reflected belowground assessment of the EM fungal community, although 5 fruiting species were found on roots. Seagrape seedlings and mature trees had very similar communities of EM fungi, dominated by S. bermudense, R. cremeolilacina, and two Thelephoraceae: shared species represented 93 % of the taxonomic EM fungal diversity and 74 % of the sampled EM root tips. Furthermore, some significant differences were observed between the frequencies of EM fungal taxa on mature trees and seedlings. The EM fungal community composition also varied between the four investigated sites. We discuss the reasons for such a species-poor community and the possible role of common mycorrhizal networks linking seagrape seedlings and mature trees in regeneration of coastal forests.
Full Text Available Previous modeling studies have identified the vaccination coverage level necessary for preventing influenza epidemics, but have not shown whether this critical coverage can be reached. Here we use computational modeling to determine, for the first time, whether the critical coverage for influenza can be achieved by voluntary vaccination. We construct a novel individual-level model of human cognition and behavior; individuals are characterized by two biological attributes (memory and adaptability that they use when making vaccination decisions. We couple this model with a population-level model of influenza that includes vaccination dynamics. The coupled models allow individual-level decisions to influence influenza epidemiology and, conversely, influenza epidemiology to influence individual-level decisions. By including the effects of adaptive decision-making within an epidemic model, we can reproduce two essential characteristics of influenza epidemiology: annual variation in epidemic severity and sporadic occurrence of severe epidemics. We suggest that individual-level adaptive decision-making may be an important (previously overlooked causal factor in driving influenza epidemiology. We find that severe epidemics cannot be prevented unless vaccination programs offer incentives. Frequency of severe epidemics could be reduced if programs provide, as an incentive to be vaccinated, several years of free vaccines to individuals who pay for one year of vaccination. Magnitude of epidemic amelioration will be determined by the number of years of free vaccination, an individuals' adaptability in decision-making, and their memory. This type of incentive program could control epidemics if individuals are very adaptable and have long-term memories. However, incentive-based programs that provide free vaccination for families could increase the frequency of severe epidemics. We conclude that incentive-based vaccination programs are necessary to control
Yu, Xiao-Ling; Wu, Xiao; Zhang, Duan-Ming; Li, Zhi-Hao; Liang, Fang; Wang, Xiao-Yu
We have studied the topology and epidemic spreading behaviors on the networks in which deactivation mechanism and long-rang connection are coexisted. By means of numerical simulation, we find that the clustering coefficient C and the Pearson correlation coefficient r decrease with increasing long-range connection μ and the topological state of the network changes into that of BA model at the end (when μ = 1). For the Susceptible Infect Susceptible model of epidemics, the epidemic threshold can reach maximum value at μ = 0.4 and presents two different variable states around μ = 0.4.
Zou, Linyou; Ross, Brian M; Hutchison, Leonard J; Christopher, Lew P; Dekker, Robert F H; Malek, Lada
Demethylation of industrial lignin has been for long coveted as a pathway to the production of an abundant natural substitute for fossil-oil derived phenol. In an attempt to possibly identify a novel Kraft lignin-demethylating enzyme, we surveyed a collection of fungi by using selected ion flow tube-mass spectrometry (SIFT-MS). This method readily identifies methanol resulting from lignin demethylation activity. Absidia cylindrospora, and unidentified Cylindrocladium sp. and Aspergillus sp. were shown to metabolize lignin via different pathways, based on the HPLC analysis of lignin fragments. Of these three, Cylindrocladium and Aspergillus were shown to retain most of the lignin intact after 3 weeks in culture, while removing about 40% of the available methoxy groups. Our results demonstrate that after optimization of culture and lignin recovery methods, biological modification of Kraft lignin may be a feasible pathway to obtaining demethylated lignin for further industrial use. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
Keller, Nancy P
Filamentous fungi are renowned for the production of a diverse array of secondary metabolites (SMs) where the genetic material required for synthesis of a SM is typically arrayed in a biosynthetic gene cluster (BGC). These natural products are valued for their bioactive properties stemming from their functions in fungal biology, key among those protection from abiotic and biotic stress and establishment of a secure niche. The producing fungus must not only avoid self-harm from endogenous SMs but also deliver specific SMs at the right time to the right tissue requiring biochemical aid. This review highlights functions of BGCs beyond the enzymatic assembly of SMs, considering the timing and location of SM production and other proteins in the clusters that control SM activity. Specifically, self-protection is provided by both BGC-encoded mechanisms and non-BGC subcellular containment of toxic SM precursors; delivery and timing is orchestrated through cellular trafficking patterns and stress- and developmental-responsive transcriptional programs.
This study set out to estimate the prevalence of atopy to a variety of common ubiquitous fungi, including A. fumigatus, in cystic fibrosis (CF), and to evaluate the investigations by which the diagnosis was made. Particular attention was paid to the usefulness of skin testing and immunoassays in detecting which patients had simple fungal atopy, and which patients were at high risk of developing allergic bronchopulmonary mycoses. This cross-sectional study included 21 adult CF patients and 20 matched controls. Serum samples were taken for the measurement of total serum IgE and specific serum IgE to nine common fungi. Immediate hypersensitivity skin prick testing to each of the fungi was also performed. Simple fungal atopy was described in subjects fulfilling the following criteria: total serum IgE > 100 KU l(-1) with specific radioimmunoassay > or = grade 1 to at least one fungus and a positive skin prick test (SPT) > or = 3 mm to the same fungus. \\'High risk\\' for developing allergic bronchopulmonary mycosis (ABPM) was described in subjects fulfilling the following criteria: total serum IgE > 200 KU l(-1) with specific radioimmunoassay > or = grade 2 to at least one fungus and a positive skin prick test (SPT) > or = 6 mm to the same fungus. The adult CF group had a significantly higher total SPT score (P=0.005) and mean total serum IgE (P<0.05) than controls. Forty-three percent of CF patients fulfilled the criteria for fungal atopy to at least a single fungus. Over half this group had an atopic tendency to more than one fungus. Nineteen percent of the CF group were at least \\'high risk\\' of developing ABPM. Skin prick testing is a better marker of fungal atopy and a better predictor of those adult CF patients at higher risk of developing ABPM than specific radioimmunoassay serum testing. There is a high prevalence of fungal atopy in the adult CF population. Total serum IgE and skin prick testing are good predictors of fungal atopy and help predict those at
Finger, F.; Bertuzzo, E.; Mari, L.; Knox, A. C.; Gatto, M.; Rinaldo, A.
Epidemiological models can provide crucial understanding about the dynamics of infectious diseases. Possible applications range from real-time forecasting and allocation of health care resources to testing alternative intervention mechanisms such as vaccines, antibiotics or the improvement of sanitary conditions. We apply a spatially explicit model to the cholera epidemic that struck Haiti in October 2010 and is still ongoing. The dynamics of susceptibles as well as symptomatic and asymptomatic infectives are modelled at the scale of local human communities. Dissemination of Vibrio cholerae through hydrological transport and human mobility along the road network is explicitly taken into account, as well as the effect of rainfall as a driver of increasing disease incidence. The model is calibrated using a dataset of reported cholera cases. We further model the long term impact of several types of interventions on the disease dynamics by varying parameters appropriately. Key epidemiological mechanisms and parameters which affect the efficiency of treatments such as antibiotics are identified. Our results lead to conclusions about the influence of different intervention strategies on the overall epidemiological dynamics.
Yip, Cyril C. Y.; Lau, Susanna K. P.; Woo, Patrick C. Y.; Yuen, Kwok-Yung
Human enterovirus 71 (EV71) epidemics have affected various countries in the past 40 years. EV71 commonly causes hand, foot and mouth disease (HFMD) in children, but can result in neurological and cardiorespiratory complications in severe cases. Genotypic changes of EV71 have been observed in different places over time, with the emergence of novel genotypes or subgenotypes giving rise to serious outbreaks. Since the late 1990s, intra- and inter-typic recombination events in EV71 have been increasingly reported in the Asia-Pacific region. In particular, ‘double-recombinant’ EV71 strains belonging to a novel genotype D have been predominant in mainland China and Hong Kong over the last decade, though co-circulating with a minority of other EV71 subgenotypes and coxsackie A viruses. Continuous surveillance and genome studies are important to detect potential novel mutants or recombinants in the near future. Rapid and sensitive molecular detection of EV71 is of paramount importance in anticipating and combating EV71 outbreaks. PMID:24119538
Newsome, Andrew G; Culver, Catherine A; van Breemen, Richard B
The food and beverage industry is seeking to broaden the palette of naturally derived colorants. Although considerable effort has been devoted to the search for new blue colorants in fruits and vegetables, less attention has been directed toward blue compounds from other sources such as bacteria and fungi. The current work reviews known organic blue compounds from natural plant, animal, fungal, and microbial sources. The scarcity of blue-colored metabolites in the natural world relative to metabolites of other colors is discussed, and structural trends common among natural blue compounds are identified. These compounds are grouped into seven structural classes and evaluated for their potential as new color additives.
Dennis L Chao
Full Text Available Mathematical and computer models of epidemics have contributed to our understanding of the spread of infectious disease and the measures needed to contain or mitigate them. To help prepare for future influenza seasonal epidemics or pandemics, we developed a new stochastic model of the spread of influenza across a large population. Individuals in this model have realistic social contact networks, and transmission and infections are based on the current state of knowledge of the natural history of influenza. The model has been calibrated so that outcomes are consistent with the 1957/1958 Asian A(H2N2 and 2009 pandemic A(H1N1 influenza viruses. We present examples of how this model can be used to study the dynamics of influenza epidemics in the United States and simulate how to mitigate or delay them using pharmaceutical interventions and social distancing measures. Computer simulation models play an essential role in informing public policy and evaluating pandemic preparedness plans. We have made the source code of this model publicly available to encourage its use and further development.
Chao, Dennis L; Halloran, M Elizabeth; Obenchain, Valerie J; Longini, Ira M
Mathematical and computer models of epidemics have contributed to our understanding of the spread of infectious disease and the measures needed to contain or mitigate them. To help prepare for future influenza seasonal epidemics or pandemics, we developed a new stochastic model of the spread of influenza across a large population. Individuals in this model have realistic social contact networks, and transmission and infections are based on the current state of knowledge of the natural history of influenza. The model has been calibrated so that outcomes are consistent with the 1957/1958 Asian A(H2N2) and 2009 pandemic A(H1N1) influenza viruses. We present examples of how this model can be used to study the dynamics of influenza epidemics in the United States and simulate how to mitigate or delay them using pharmaceutical interventions and social distancing measures. Computer simulation models play an essential role in informing public policy and evaluating pandemic preparedness plans. We have made the source code of this model publicly available to encourage its use and further development.
Geml, József; Gravendeel, Barbara; van der Gaag, Kristiaan J; Neilen, Manon; Lammers, Youri; Raes, Niels; Semenova, Tatiana A; de Knijff, Peter; Noordeloos, Machiel E
Western European coastal sand dunes are highly important for nature conservation. Communities of the creeping willow (Salix repens) represent one of the most characteristic and diverse vegetation types in the dunes. We report here the results of the first kingdom-wide fungal diversity assessment in S. repens coastal dune vegetation. We carried out massively parallel pyrosequencing of ITS rDNA from soil samples taken at ten sites in an extended area of joined nature reserves located along the North Sea coast of the Netherlands, representing habitats with varying soil pH and moisture levels. Fungal communities in Salix repens beds are highly diverse and we detected 1211 non-singleton fungal 97% sequence similarity OTUs after analyzing 688,434 ITS2 rDNA sequences. Our comparison along a north-south transect indicated strong correlation between soil pH and fungal community composition. The total fungal richness and the number OTUs of most fungal taxonomic groups negatively correlated with higher soil pH, with some exceptions. With regard to ecological groups, dark-septate endophytic fungi were more diverse in acidic soils, ectomycorrhizal fungi were represented by more OTUs in calcareous sites, while detected arbuscular mycorrhizal genera fungi showed opposing trends regarding pH. Furthermore, we detected numerous red listed species in our samples often from previously unknown locations, indicating that some of the fungal species currently considered rare may be more abundant in Dutch S. repens communities than previously thought.
Miwa, C; Watanabe, Y
During the period from May to August, 1984, an epidemic of infectious disease with echovirus type 16 occurred in Tono area of southeast in Gifu prefecture. This virus caused children to have different clinical symptoms, one was a exanthem disease and another was aseptic meningitis. These cases confirmed by virological and serological methods were 48 cases, that is, patients with aseptic meningitis were 24 cases and patients with exanthem disease were 24 cases. By serological examination of antibody against echovirus type 16, it was confirmed that this virus type invaded Gifu Prefecture before 1984.
Fischer, Cristine D B; Gräf, Tiago; Ikuta, Nilo; Lehmann, Fernanda K M; Passos, Daniel T; Makiejczuk, Aline; Silveira, Marcos A T; Fonseca, André S K; Canal, Cláudio W; Lunge, Vagner R
Canine distemper virus (CDV) is a highly contagious pathogen for domestic dogs and several wild carnivore species. In Brazil, natural infection of CDV in dogs is very high due to the large non-vaccinated dog population, a scenario that calls for new studies on the molecular epidemiology. This study investigates the phylodynamics and amino-acid signatures of CDV epidemic in South America by analyzing a large dataset compiled from publicly available sequences and also by collecting new samples from Brazil. A population of 175 dogs with canine distemper (CD) signs was sampled, from which 89 were positive for CDV, generating 42 new CDV sequences. Phylogenetic analysis of the new and publicly available sequences revealed that Brazilian sequences mainly clustered in South America 1 (SA1) clade, which has its origin estimated to the late 1980's. The reconstruction of the demographic history in SA1 clade showed an epidemic expanding until the recent years, doubling in size every nine years. SA1 clade epidemic distinguished from the world CDV epidemic by the emergence of the R580Q strain, a very rare and potentially detrimental substitution in the viral genome. The R580Q substitution was estimated to have happened in one single evolutionary step in the epidemic history in SA1 clade, emerging shortly after introduction to the continent. Moreover, a high prevalence (11.9%) of the Y549H mutation was observed among the domestic dogs sampled here. This finding was associated (p<0.05) with outcome-death and higher frequency in mixed-breed dogs, the later being an indicator of a continuous exchange of CDV strains circulating among wild carnivores and domestic dogs. The results reported here highlight the diversity of the worldwide CDV epidemic and reveal local features that can be valuable for combating the disease. Copyright © 2016 Elsevier B.V. All rights reserved.
Moore, S; Thomson, N; Mutreja, A; Piarroux, R
Since 1817, seven cholera pandemics have plagued humankind. As the causative agent, Vibrio cholerae, is autochthonous in the aquatic ecosystem and some studies have revealed links between outbreaks and fluctuations in climatic and aquatic conditions, it has been widely assumed that cholera epidemics are triggered by environmental factors that promote the growth of local bacterial reservoirs. However, mounting epidemiological findings and genome sequence analysis of clinical isolates have indicated that epidemics are largely unassociated with most of the V. cholerae strains in aquatic ecosystems. Instead, only a specific subset of V. cholerae El Tor 'types' appears to be responsible for current epidemics. A recent report examining the evolution of a variety of V. cholerae strains indicates that the current pandemic is monophyletic and originated from a single ancestral clone that has spread globally in successive waves. In this review, we examine the clonal nature of the disease, with the example of the recent history of cholera in the Americas. Epidemiological data and genome sequence-based analysis of V. cholerae isolates demonstrate that the cholera epidemics of the 1990s in South America were triggered by the importation of a pathogenic V. cholerae strain that gradually spread throughout the region until local outbreaks ceased in 2001. Latin America remained almost unaffected by the disease until a new toxigenic V. cholerae clone was imported into Haiti in 2010. Overall, cholera appears to be largely caused by a subset of specific V. cholerae clones rather than by the vast diversity of V. cholerae strains in the environment. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.
Full Text Available BACKGROUND: Zipf's law and Heaps' law are two representatives of the scaling concepts, which play a significant role in the study of complexity science. The coexistence of the Zipf's law and the Heaps' law motivates different understandings on the dependence between these two scalings, which has still hardly been clarified. METHODOLOGY/PRINCIPAL FINDINGS: In this article, we observe an evolution process of the scalings: the Zipf's law and the Heaps' law are naturally shaped to coexist at the initial time, while the crossover comes with the emergence of their inconsistency at the larger time before reaching a stable state, where the Heaps' law still exists with the disappearance of strict Zipf's law. Such findings are illustrated with a scenario of large-scale spatial epidemic spreading, and the empirical results of pandemic disease support a universal analysis of the relation between the two laws regardless of the biological details of disease. Employing the United States domestic air transportation and demographic data to construct a metapopulation model for simulating the pandemic spread at the U.S. country level, we uncover that the broad heterogeneity of the infrastructure plays a key role in the evolution of scaling emergence. CONCLUSIONS/SIGNIFICANCE: The analyses of large-scale spatial epidemic spreading help understand the temporal evolution of scalings, indicating the coexistence of the Zipf's law and the Heaps' law depends on the collective dynamics of epidemic processes, and the heterogeneity of epidemic spread indicates the significance of performing targeted containment strategies at the early time of a pandemic disease.
Huizer, Y.L.; Kraaij-Dirkzwager, M.M.; Timen, A.; Schuitmaker-Warnaar, T.J.; van Steenbergen, J.E.
When epidemics occur, experts advise the Ministries on effective control measures. There is uncertainty in the translation of epidemiological evidence into effective outbreak management interventions, due to contradicatory problem perspectives, diverse interests and time pressure. Several models
Allen, Linda J S
This monograph provides a summary of the basic theory of branching processes for single-type and multi-type processes. Classic examples of population and epidemic models illustrate the probability of population or epidemic extinction obtained from the theory of branching processes. The first chapter develops the branching process theory, while in the second chapter two applications to population and epidemic processes of single-type branching process theory are explored. The last two chapters present multi-type branching process applications to epidemic models, and then continuous-time and continuous-state branching processes with applications. In addition, several MATLAB programs for simulating stochastic sample paths are provided in an Appendix. These notes originated as part of a lecture series on Stochastics in Biological Systems at the Mathematical Biosciences Institute in Ohio, USA. Professor Linda Allen is a Paul Whitfield Horn Professor of Mathematics in the Department of Mathematics and Statistics ...
Duan, Wei; Qiu, Xiaogang; Quax, Rick; Lees, Michael; Sloot, Peter M A
Many diffusive processes occur on structured networks with weighted links, such as disease spread by airplane transport or information diffusion in social networks or blogs. Understanding the impact of weight-connectivity correlations on epidemic spreading in weighted networks is crucial to support decision-making on disease control and other diffusive processes. However, a real understanding of epidemic spreading velocity in weighted networks is still lacking. Here we conduct a numerical study of the velocity of a Reed–Frost epidemic spreading process in various weighted network topologies as a function of the correlations between edge weights and node degrees. We find that a positive weight-connectivity correlation leads to a faster epidemic spreading compared to an unweighted network. In contrast, we find that both uncorrelated and negatively correlated weight distributions lead to slower spreading processes. In the case of positive weight-connectivity correlations, the acceleration of spreading velocity is weak when the heterogeneity of weight distribution increases. (paper)