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Worldwide Distribution (worldwide + distribution)
Selected AbstractsWorldwide distribution of Pseudomonas aeruginosa clone C strains in the aquatic environment and cystic fibrosis patientsENVIRONMENTAL MICROBIOLOGY, Issue 7 2005Ute Römling Summary Highly successful bacterial clones have the ability to effectively colonize environmental niches and patients. However, the factors which determine the complex interplay between the colonization of environmental niches and patients are mainly unknown. In this study we show that Pseudomonas aeruginosa clone C strains are distributed worldwide and highly prone to infect cystic fibrosis (CF) patients in Canada, England, France and Germany. In Hanover, Germany and Vancouver, Canada, clone C strains are highly prevalent in the CF patient community, although the mechanisms of acquisition may have been different. All clone C strains showed highly related macrorestriction fragment pattern of the whole genome as visualized by pulsed-field gel electrophoresis and harboured the 102 kbp plasmid pKLC102. Comparison of three prevalent P. aeruginosa clones with different distribution between the environment and patients revealed that neither enhanced biofilm formation nor antibiotic resistance was responsible for the spread of clone C. Clone M, which was highly prevalent in the clinical environment such as sanitary facilities, lacked motility, which could explain its relatively low prevalence in CF patients. Elucidation of the mechanisms which lead to the prevalence of clone C strain in patients and the environment requires the investigation of additional phenotypes. [source] Effects of exposure to oxamyl, carbofuran, dichlorvos, and lindane on acetylcholinesterase activity in the gills of the Pacific oyster Crassostrea gigasENVIRONMENTAL TOXICOLOGY, Issue 4 2010Gerardo A. Anguiano Abstract Acetylcholinesterase (AChE) activity has been used to test the exposure of mollusk bivalves to pesticides and other pollutants. The Pacific oyster Crassostrea gigas is a species with a worldwide distribution, and it has a high commercial value. The use of this species as a bioindicator in the marine environment, and the use of measurements of AChE activity in tissues of C. gigas require prior evaluation of organisms exposed to several toxic compounds in the laboratory. In our study, the effects of pesticides on AChE activity in the gills and mantle tissues of C. gigas were analyzed by exposing animals to organophosphate (dichlorvos), carbamate (carbofuran and oxamyl), and organochlorine (lindane) pesticides. Adult Pacific oysters were exposed to several concentrations (0.1,200 ,M) of dichlorvos, carbofuran, and oxamyl for 96 h, and lindane (1.0 and 2.5 ,M) was applied for 12 days. In gill tissues, all pesticides analyzed caused a decrease in AChE activity when compared to the control unexposed group. The mean inhibition concentration (IC50) values were determined for dichlorvos, carbofuran, and oxamyl pesticides. Dichlorvos had the highest toxic effect, with an IC50 of 1.08 ,M; lesser effects were caused by oxamyl and carbofuran, with IC50s of 1.67 and 3.03 ,M, respectively. This study reports the effects of pesticides with several chemical structures and validates measurement of AChE activity in the gill tissues of C. gigas for use in environmental evaluations or food quality tests. © 2009 Wiley Periodicals, Inc. Environ Toxicol 25: 327,332, 2010. [source] Equine recurrent uveitis: A clinical manifestation of leptospirosisEQUINE VETERINARY EDUCATION, Issue 10 2009L. Frellstedt Summary Leptospirosis is a zoonosis of worldwide distribution affecting domestic animals, wildlife and man. The bacterial disease is caused by pathogenic Leptospira spp., which are transmitted from reservoir hosts to accidental hosts. Horses are accidental hosts and can become susceptible to leptospiral infections. Widespread exposure to leptospires exists and is significantly more common than clinical disease. Leptospirosis can have different clinical manifestations including abortion, still birth, systemic disease with hepatic or renal dysfunction, and equine recurrent uveitis (ERU). ERU is the most frequently encountered clinical manifestation and this article will focus on the review of leptospira-associated ERU. Equine recurrent uveitis is the most common cause of vision impairment and blindness in horses. The pathogenesis of leptospira-associated ERU involves direct bacterial effects and immune-mediated responses. Clinical signs vary between the acute and chronic phases of the disease and progress over time. The diagnosis of leptospira-associated ERU can be difficult and usually requires a combination of diagnostic tests. Medical and surgical treatments have been described with varying outcomes. The prognosis for sight is usually poor, although core vitrectomy may improve the outcome. Avoidance of leptospiral exposure of horses is the only reliable prevention of leptospira-associated disease. [source] New taxonomic concepts for the important forest pathogen Cryphonectria parasitica and related fungiFEMS MICROBIOLOGY LETTERS, Issue 2 2006Marieka Gryzenhout Abstract Species of Cryphonectria include some of the world's most important and devastating tree pathogens. Largely through the application of DNA sequence phylogenies, the taxonomy of these fungi has undergone major changes in recent years. Cryphonectria, including the chestnut blight pathogen Cryphonectria parasitica, has been restricted to species that have semi-immersed stromata, orange and pulvinate conidiomata, and one-septate ascospores. Other species of Cryphonectria with different morphological characteristics have been transferred to new genera that are strongly supported by phylogenetic data. This review represents a summary of the taxonomic changes to species of Cryphonectria sensu lato, and we discuss the impact that these changes might have on the understanding of their ecology, pathology and worldwide distribution. [source] Screening of ARHSP-TCC patients expands the spectrum of SPG11 mutations and includes a large scale gene deletion,HUMAN MUTATION, Issue 3 2009Paola S. Denora Abstract Autosomal recessive spastic paraplegia with thinning of corpus callosum (ARHSP-TCC) is a complex form of HSP initially described in Japan but subsequently reported to have a worldwide distribution with a particular high frequency in multiple families from the Mediterranean basin. We recently showed that ARHSP-TCC is commonly associated with mutations in SPG11/KIAA1840 on chromosome 15q. We have now screened a collection of new patients mainly originating from Italy and Brazil, in order to further ascertain the spectrum of mutations in SPG11, enlarge the ethnic origin of SPG11 patients, determine the relative frequency at the level of single Countries (i.e., Italy), and establish whether there is one or more common mutation. In 25 index cases we identified 32 mutations; 22 are novel, including 9 nonsense, 3 small deletions, 4 insertions, 1 in/del, 1 small duplication, 1 missense, 2 splice-site, and for the first time a large genomic rearrangement. This brings the total number of SPG11 mutated patients in the SPATAX collection to 111 cases in 44 families and in 17 isolated cases, from 16 Countries, all assessed using homogeneous clinical criteria. While expanding the spectrum of mutations in SPG11, this larger series also corroborated the notion that even within apparently homogeneous population a molecular diagnosis cannot be achieved without full gene sequencing. © 2008 Wiley-Liss, Inc. [source] Severe pulmonary haemorrhage accompanying hepatorenal failure in fulminant leptospirosisINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 1 2007B. Dursun Summary Leptospirosis is a re-emerging spirochetal zoonosis with a worldwide distribution affecting both animals and humans. The clinical syndromes may vary from a subclinical infection to a severe illness. Although it may potentially have a fulminant and fatal course, leptospirosis usually remains as an underdiagnosed cause of multiorgan failure. In this study, we report a patient with leptospirosis who presented with a fulminant course of diffuse alveolar haemorrhage and hepatorenal failure. His clinical condition deteriorated, despite appropriate antibiotic therapy and haemodialysis. However, he showed prompt clinical improvement when corticosteroids and plasma exchange were instituted in addition to the original therapy. We conclude that leptospirosis should be considered in any case presenting with pulmonary haemorrhage and hepatorenal failure. Plasma exchange and corticosteroids may be a choice of treatment in selected patients unresponsive to conventional therapy. Potential benefits of plasma exchange and corticosteroids may be based on a toxin- and/or cytokine-mediated pathogenesis of the disease. [source] Comparisons of calling behaviour of different geographical populations of Helicoverpa armigeraJOURNAL OF APPLIED ENTOMOLOGY, Issue 9-10 2007X.-C. Zhao Abstract:, The cotton bollworm, Helicoverpa armigera, with worldwide distribution, evolves into different geotypes for adapting to the changes of geographical climates. Comparisons of calling behaviour of the insect collected from the temperate region in northern China (Beijing), the temperate region in north-western China (Kashi) and the tropical region in southern China (Haikou) were investigated in the laboratory as a first step to understanding the influence of reproductive behaviour on its population differentiation. There were more than 80% of virgin females of each population that showed calling behaviour. The age at which the moths of all three populations initiated calling varied significantly. The durations of calling in scotophase and the percentages of females calling also differed between populations. Only a few females of the Beijing and Haikou populations called in the first 2 h after the onset of scotophase, whereas many Kashi females called at this time. However, the main calling peak occurred during the second half of scotophase for all three populations. Females of the Beijing and Haikou populations exhibited similar calling onset times at the same age, whereas the Kashi females initiated calling significantly earlier than those of Beijing and Haikou from nights 3 to 7. The durations of each calling bout and the time spent by both Beijing and Haikou populations were similar to each other at the same age, but were significantly shorter than that of the Kashi population from nights 3 to 7. These results suggest that there are genetic variations not only in pre-period calling but also in the calling behaviour of H. armigera. [source] Multiplex PCR detection of slowly-evolving trypanosomatids and neogregarines in bumblebees using broad-range primersJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2010I. Meeus Abstract Aims:, The aims of this study were to design universal markers for different protozoan parasites of Bombus spp. based on the phylogenetic position of two important bumblebee parasites Crithidia bombi and Apicystis bombi. Methods and Results:, Standard PCR and extraction techniques were used to amplify and sequence 18S rDNA. Phylogenetic analysis of the rDNA was performed in order to predict the parasite range of the primers. Conclusions:,Crithidia bombi phylogenetically clusters with the trypanosomatids with slowly-evolving SSU-rRNA sequences (SE), while A. bombi is the closest sister group of Mattesia. A multiplex was designed containing an internal control and two broad-range primer pairs, detecting C. bombi and other SE trypanosomatids and also A. bombi and other neogregarines. Significance and Impact of the Study:, Sequence data generated will further improve the current systematics of insect trypanosomatids and gregarines that remain troublesome. Broad-range markers for bumblebee parasites are necessary tools enabling the screening of commercially imported colonies and thus controlling their worldwide distribution and to discover related emerging parasites. [source] Intra-oral Dirofilaria repens infection: report of seven casesJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2003W. M. Tilakaratne Abstract Cutaneous dirofilariasis usually affects animals such as cats and dogs which are known to be the natural host of Dirofilaria. Dirofilariasis displays a worldwide distribution. Certain geographic regions account for the majority of reported cases. South-eastern United States, Australia and Europe have been identified as endemic regions (1, 2). However, new endemic areas are arising with increased awareness in African and Asian regions. Out of about 40 different species of Dirofilaria only a few species are commonly known to infect man, namely Dirofilaria immitus, D. tenices and D. repens. Human infection occurs when a human becomes a blood meal of an infected arthropod vector and on accidental entering of the worm. Rarely this zoonotic infection affects the oral mucosa (3). Man is the dead end of this parasite. Since the human body is an abnormal environment for the parasite, the development of the larvae is inhibited by means of retardation of sexual maturity. Lesions are presented as single non-tender subcutaneous nodules, and most patients are asymptomatic. Diagnosis is established by H&E sections prepared from excised nodules. In a majority of the cases, only a single worm either a male or a female could be identified. The worm is usually dead and degenerated with a massive inflammatory cell infiltration. Seven new cases presented as intra-oral nodules with their clinicopathological correlation are discussed. [source] SYSTEMATICS OF GRACILARIOPSIS (GRACILARIALES, RHODOPHYTA) BASED ON rbcL SEQUENCE ANALYSES AND MORPHOLOGICAL EVIDENCE,JOURNAL OF PHYCOLOGY, Issue 1 2003Carlos Frederico D. Gurgel A phylogeny has been inferred from parsimony and likelihood analyses of plastid rbcL DNA sequences for seven recognized and six undescribed species of Gracilariopsis (Gp.) (Gracilariales, Rhodophyta). New descriptions and illustrations of cystocarp morphology are provided for four Gracilariopsis species from North and South America. The generitype, Gp. sjoestedtii (Kylin) Dawson, is reinstated to include plants distributed from British Columbia to Pacific Baja California, and the name is corrected to Gp. andersonii (Grunow) Dawson. Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik is shown not to have a worldwide distribution but to be restricted to the vicinity of Peru. Gracilariopsis costaricensis is recognized with the provision that it may prove to be conspecific with Gp. lemaneiformis. Gracilariopsis "lemaneiformis" from North and South Carolina is described as a new species, Gp. carolinensis Liao et Hommersand sp. nov. Gracilariopsis longissima (Gmelin) Steentoft, Irvine et Farnham from Western Europe and the Mediterranean Sea and Gp. tenuifrons (Bird et Oliveira) Fredericq et Hommersand from the Ca-ribbean Sea and Brazil are recognized. Entities that have been referred to Gp. "lemaneiformis" from China and Japan constitute an undescribed species that is related to Gp. heteroclada Zhang et Xia. An invasive species from the Gulf of California, Mexico, and South Australia that has been assigned to Gp. "lemaneiformis" is resolved in a clade that includes Gp. longissima. Four undescribed species are included in the molecular analyses. The systematics of Gracilariopsis is discussed in the light of the morphological and molecular evidence. [source] BIOGEOGRAPHY OF MARINE RED ALGAE: MYTHS AND REALITIESJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Hommersand, M. H. Department of Biology, Coker Hall, University of North Carolina, Chapel Hill, NC 27599-3280 USA Theories about the geographical distribution of marine algae fall roughly into two categories: (1) a concept of biogeographical regions in which algal distribution is determined primarily by growth, reproductive and lethal temperature boundaries (Setchell, van den Hoek, Breeman, Lüning) and (2) an historical perspective in which distribution is determined primarily by patterns of dispersal and the establishment of barriers to dispersal (vicariance biogeography) (Svedelius, Garbary, Lindstrom, Hommersand). Setchell proposed the 5° isotherm rule in 1920, and in 1924 Svedelius advocated a worldwide distribution for tropical and subtropical groups followed by discontinuous distribution upon closure of the connection between the Indian Ocean and Mediterranean Sea and, later, between North and South America (Wegener's theory). Transarctic dispersal routes have received special attention in recent years (Lindstrom, Lüning, van Oppen, Olsen, Stam), as have special relationships between Australasia, South Africa and South America (Hommersand). Less well understood are the climatic changes that have taken place in the Cenozoic which are strategic to an understanding vicariant biogeography. The advent of molecular methods combined with the tools of phylogenetic systematics now make it possible to identify ancestral taxa, test the consistency of tree topologies, and calculate mean branch lengths between sister lineages diverging from an interior node of a tree. With such methods it may be possible to infer ancestral areas, identify dispersal pathways, determine the chronology of isolating events, assess the impact of multiple invasions, and generally relate dispersal and vicariance models to phylogenetic hypotheses for red, brown and green algal taxa. [source] A new model organism among the lower Bilateria and the use of digital microscopy in taxonomy of meiobenthic Platyhelminthes: Macrostomum lignano, n. sp. (Rhabditophora, Macrostomorpha)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2005P. Ladurner Abstract Macrostomum lignano n. sp. is a member of the Macrostomorpha, the basal-most subtaxon of the Platyhelminthes,Rhabditophora. This new species can be easily cultured in the laboratory and has been already the subject of several developmental/evolutionary studies. The small size, with only about 25 000 cells constituting the major bilaterian organ systems, makes this simultaneous hermaphrodite a possible candidate for a new model organism that is phylogenetically more basal than any of the model organisms currently used in such studies within the Bilateria. M. lignano belongs to the largest genus of the Macrostomorpha. Over 100 marine, fresh water and brackish water species are contained in the genus Macrostomum, some of them with worldwide distribution pattern. Within it, M. lignano is a member of the M. tuba -species group, which we have summarized here. In the species description, we have used a novel approach to document such small soft-bodied meiobenthic organisms: we provide extensive digital micrographical documentation, which are deposited as a CD together with the type material. Zusammenfassung Macrostomum lignano n. sp. gehört zu den Macrostomorpha, dem ursprünglichsten Subtaxon der Plathelminthes-Rhabditophora. An der neuen Art, die sich im Labor besonders einfach züchten lässt, wurden bereits zahlreiche entwicklungsbiologische und evolutionsbiologische Studien durchgeführt. Die kleinen simultan-hermaphroditischen Tiere, bei denen nur etwa 25'000 Zellen alle wichtigen Organsysteme der Bilateria ausbilden, sind für derartige Untersuchungen ein möglicher Modellorganismus, der phylogenetisch weit ursprünglicher ist als die üblichen Modellorganismen. Macrostomum ist die größte Gattung der Macrostomorpha. Sie umfasst mehr als 100 Meer-, Süss- und Brackwasser-Arten, einige davon mit weltweiter Verbreitung. Innerhalb der Gattung ist M. lignano der M. tuba -Artengruppe zuzurechnen, die zusammenfassend dargestellt wird. Zur Charakterisierung dieser meiobenthischen neuen Art wird als neuartige Dokumentationsform digitales Bildmaterial verwendet, das als CD zusammen mit dem Typenmaterial hinterlegt wird. [source] Bipolaris sorokiniana, a cereal pathogen of global concern: cytological and molecular approaches towards better control,MOLECULAR PLANT PATHOLOGY, Issue 4 2002Jagdish Kumar Summary Bipolaris sorokiniana (teleomorph Cochliobolus sativus ) is the causal agent of common root rot, leaf spot disease, seedling blight, head blight, and black point of wheat and barley. The fungus is one of the most serious foliar disease constraints for both crops in warmer growing areas and causes significant yield losses. High temperature and high relative humidity favour the outbreak of the disease, in particular in South Asia's intensive ,irrigated wheat,rice' production systems. In this article, we review the taxonomy and worldwide distribution, as well as strategies to counteract the disease as an emerging threat to cereal production systems. We also review the current understanding of the cytological and molecular aspects of the interaction of the fungus with its cereal hosts, which makes B. sorokiniana a model organism for studying plant defence responses to hemibiotrophic pathogens. The contrasting roles of cell death and H 2O2 generation in plant defence during biotrophic and necrotrophic fungal growth phases are discussed. [source] A parasite-driven wedge: infectious diseases may explain language and other biodiversityOIKOS, Issue 9 2008Corey L. Fincher Parasite,host coevolutionary races are spatially variable across species' or human cultural ranges. Assortative sociality, biased toward local conspecifics, and limited dispersal (philopatry) in humans and other organisms can be adaptive through reduced contact with dangerous contagions harbored by distant/non-local conspecifics. These factors can generate cultural or population divergence. Thus, parasites are like a wedge driving groups apart through their effective creation of anticontagion behaviors. If this proposition is correct, then biological diversity should positively correlate with parasite diversity. Here we show that the worldwide distribution of indigenous human language diversity, a form of biodiversity, is strongly, positively related to human parasite diversity indicative of a legacy of parasite-mediated diversification. The significant pattern remains when potential confounds are removed. The pattern too is seen in each of the six world regions and is not confounded by regional differences in their history of colonization and conquest. We hypothesize that variation in limited dispersal and assortative sociality with conspecifics in response to the worldwide spatial variation in pathogen diversity provides a fundamental mechanism of population divergence explaining many important aspects of the geographic patterns of biodiversity. This hypothesis has broad implications for a diversity of research topics including language diversity, cultural evolution, speciation, phylogeny and biogeography. [source] Photodynamic Treatment of the Dermatophyte Trichophyton rubrum and its Microconidia with Porphyrin Photosensitizers,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2004Threes G. M. Smijs ABSTRACT The application of photosensitizers for the treatment of fungal infections is a new and promising development within the field of photodynamic treatment (PDT). Dermatophytes, fungi that can cause infections of the skin, hair and nails, are able to feed on keratin. Superficial mycoses are probably the most prevalent of infectious diseases in all parts of the world. One of the most important restrictions of the current therapeutic options is the return of the infection and the duration of the treatment. This is especially true in the case of infections of the nail (tinea unguium) caused by Trichophyton rubrum, an anthropophilic dermatophyte with a worldwide distribution. Recently, we demonstrated that 5,10,15-tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride (Sylsens B) and deuteroporphyrin monomethylester were excellent photosensitizers toward T. rubrum when using broadband white light. This study demonstrates the photodynamic activity of these photosensitizers with red light toward both a suspension culture of T. rubrum and its isolated microconidia. The higher penetration depth of red light is important for the PDT of nail infections. In addition, we tested the photodynamic activity of a newly synthesized porphyrin, quinolino-[4,5,6,7-efg]-7-demethyl-8-deethylmesoporphyrin dimethylester, displaying a distinct peak in the red part of the spectrum. However, its photodynamic activity with red light toward a suspension culture of T. rubrum appeared to be only fungistatic. Sylsens B was the best photosensitizer toward both T. rubrum and its microconidia. A complete inactivation of the fungal spores and destruction of the fungal hyphae was found. In studies into the photostability, Sylsens B appeared to be photostable under the conditions used for fungal PDT. A promising result of this study is the demonstration of the complete degradation of the fungal hyphae in the time after the PDT and the inactivation of fungal spores, both with red light. These results offer the ingredients for a future treatment of fungal infections, including those of the nail. [source] Effect of external pH on the growth, photosynthesis and photosynthetic electron transport of Chlamydomonas acidophila Negoro, isolated from an extremely acidic lake (pH 2.6)PLANT CELL & ENVIRONMENT, Issue 10 2005ANTJE GERLOFF-ELIAS ABSTRACT In extremely acidic lakes, low primary production rates have been measured. We assumed that proton stress might explain these observations and therefore investigated the photosynthetic behaviour of a Chlamydomonas species, a main primary producer in acidic lakes, over a range of pH values. Identified as C. acidophila using small subunit rDNA analysis, this species is identical to other isolates from acidic environments in Europe and South America, suggesting a worldwide distribution. Laboratory experiments with C. acidophila, revealed a broad pH-tolerance for growth and photosynthesis, the lower pH limit lying at pH 1.5 and the upper limit at pH 7. Growth rates at optimum pH conditions (pH 3 and 5) were equal to those of the mesophilic Chlamydomonas reinhardtii. In contrast, photosynthetic rates were significantly higher, suggesting that higher photosynthetic rates compensated for higher dark respiration rates, as confirmed experimentally. Electron transport capacities of PSI and PSII, P700+ re-reduction times and measurements of PSII fluorescence revealed the induction of alternative electron transport mechanisms, such as chlororespiration, state transitions and cyclic electron transport, only at suboptimal pH values (pH 1.5; 4 and 6,7). The results indicate, that C. acidophila is well adapted to low pH and that the relatively low primary production rates are not a result of pH stress. [source] The History of Toxoplasma gondii,The First 100 YearsTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 6 2008JITENDER P. DUBEY ABSTRACT. In this paper the history of Toxoplasma gondii and toxoplasmosis is reviewed. This protozoan parasite was first discovered in 1908 and named a year later. Its medical importance remained unknown until 1939 when T. gondii was identified in tissues of a congenitally infected infant, and veterinary importance became known when it was found to cause abortion storms in sheep in 1957. The discovery of a T. gondii specific antibody test, Sabin,Feldman dye test in 1948 led to the recognition that T. gondii is a common parasite of warm-blooded hosts with a worldwide distribution. Its life cycle was not discovered until 1970 when it was found that felids are its definitive host and an environmentally resistant stage (oocyst) is excreted in feces of infected cats. The recent discovery of its common infection in certain marine wildlife (sea otters) indicates contamination of our seas with T. gondii oocysts washed from land. Hygeine remains the best preventive measure because currently there is no vaccine to prevent toxoplasmosis in humans. [source] Detection of the Dinozoans Pfiesteria piscicida and P. shumwayae: A Review of Detection Methods and Geographic Distribution,THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2 2005PARKE A. RUBLEE Abstract. Molecular methods, including conventional PCR, real-time PCR, denaturing gradient gel electrophoresis, fluorescent fragment detection PCR, and fluorescent in situ hybridization, have all been developed for use in identifying and studying the distribution of the toxic dinoflagellates Pfiesteria piscicida and P. shumwayae. Application of the methods has demonstrated a worldwide distribution of both species and provided insight into their environmental tolerance range and temporal changes in distribution. Genetic variability among geographic locations generally appears low in rDNA genes, and detection of the organisms in ballast water is consistent with rapid dispersal or high gene flow among populations, but additional sequence data are needed to verify this hypothesis. The rapid development and application of these tools serves as a model for study of other microbial taxa and provides a basis for future development of tools that can simultaneously detect multiple targets. [source] Colonisation of barley roots by endophytic Fusarium equiseti and Pochonia chlamydosporia: Effects on plant growth and diseaseANNALS OF APPLIED BIOLOGY, Issue 3 2009J.G. Maciá-Vicente Abstract Colonisation of plant roots by endophytic fungi may confer benefits to the host such as protection against abiotic or biotic stresses or plant growth promotion. The exploitation of these properties is of great relevance at an applied level, either to increase yields of agricultural crops or in reforestation activities. Fusarium equiseti is a naturally occurring endophyte in vegetation under stress in Mediterranean ecosystems. Pochonia chlamydosporia is a nematode egg-parasitic fungus with a worldwide distribution. Both fungi have the capacity to colonise roots of non-host plants endophytically and to protect them against phytopathogenic fungi under laboratory conditions. The aim of this study was to evaluate the root population dynamics of these fungi under non-axenic practical conditions. Both fungal species were inoculated into barley roots. Their presence in roots and effects on plant growth and incidence of disease caused by the pathogen Gaeumannomyces graminis var. tritici were monitored periodically. Both fungi colonised barley roots endophytically over the duration of the experiment and competed with other existing fungal root colonisers. Furthermore, colonisation of roots by P. chlamydosporia promoted plant growth. Although a clear suppressive effect on disease could not be detected, F. equiseti isolates reduced the mean root lesion length caused by the pathogen. Results of this work suggest that both F. equiseti and P. chlamydosporia are long-term root endophytes that confer beneficial effects to the host plant. [source] Recombinant proteins in the diagnosis of toxoplasmosisAPMIS, Issue 8 2010DUPADAHALLI KOTRESHA Kotresha D, Rahmah N. Recombinant proteins in the diagnosis of toxoplasmosis. APMIS 2010; 118: 529,42. Toxoplasma gondii is an important human pathogen with a worldwide distribution. It is primarily of medical importance for pregnant women and immunocompromised patients. Primary infection of the former is often associated with fetal infection, which can lead to abortion or severe neonatal malformation. Immunocompromised patients are at risk of contracting the severe form of the disease that may be fatal. Thus, detection of T. gondii infection with high sensitivity and specificity is crucial in the management of the disease. Toxoplasmosis is generally diagnosed by demonstrating specific immunoglobulin M (IgM) and IgG antibodies to toxoplasma antigens in the patient's serum sample. Most of the commercially available tests use T. gondii native antigens and display wide variations in test accuracy. Recombinant antigens have great potential as diagnostic reagents for use in assays to detect toxoplasmosis. Thus in this review, we address recent advances in the use of Toxoplasma recombinant proteins for serodiagnosis of toxoplasmosis. [source] Creutzfeldt,Jakob disease with PRNP G114V mutation in a Chinese familyACTA NEUROLOGICA SCANDINAVICA, Issue 6 2010Z. Liu Liu Z, Jia L, Piao Y, Lu D, Wang F, Lv H, Lu Y, Jia J. Creutzfeldt,Jakob disease with PRNP G114V mutation in a Chinese family. Acta Neurol Scand: 2010: 121: 377,383. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Background,,, Recent evidence has shown clinical phenotypic heterogeneity of inherited prion diseases, even between patients harbouring the same mutation in the PRNP gene. Objective and methods,,, We collected clinical data from a Chinese family with autosomal dominant dementia and screened the PRNP gene on 28 living members. A stereotactic biopsy of the right frontal lobe of the proband was performed. Results,,, The family comprised four affected individuals within two successive generations. The age of onset was in 30 or 40 s, and the duration was about 2,3 years. Clinical features of the affected members included neuropsychiatric disturbances, progressive dementia and extrapyramidal symptoms. Immunostaining for prion protein showed fine granular deposits of PrPsc in the neuropil. The PRNP gene analysis demonstrated a heterozygous G114V mutation in 15 family members. The proband was diagnosed as familial Creutzfeldt,Jakob disease (fCJD). Conclusion,,, This study strengthens the linkage of the G114V mutation to CJD. It supports the worldwide distribution of fCJD despite differences in genetic background. [source] Guidelines for the diagnosis of tick-borne bacterial diseases in EuropeCLINICAL MICROBIOLOGY AND INFECTION, Issue 12 2004P. Brouqui Abstract Ticks are obligate haematophagous acarines that parasitise every class of vertebrate (including man) and have a worldwide distribution. An increasing awareness of tick-borne diseases among clinicians and scientific researchers has led to the recent description of a number of emerging tick-borne bacterial diseases. Since the identification of Borrelia burgdorferi as the agent of Lyme disease in 1982, 11 tick-borne human bacterial pathogens have been described in Europe. Aetiological diagnosis of tick-transmitted diseases is often difficult and relies on specialised laboratories using very specific tools. Interpretation of laboratory data is very important in order to establish the diagnosis. These guidelines aim to help clinicians and microbiologists in diagnosing infection transmitted by tick bites and to provide the scientific and medical community with a better understanding of these infectious diseases. [source] | |||||||||||||