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1.
BMC Microbiol ; 23(1): 42, 2023 02 15.
Article in English | MEDLINE | ID: mdl-36792979

ABSTRACT

BACKGROUND: Artisanal and small-scale gold mining activities are producing contamination with heavy metals and metalloids (HMM) into soils and water worldwide. The HMM are considered as one of the major abiotic stresses due to their long-term persistence in soil. In this context, arbuscular mycorrhizal fungi (AMF) confer resistance to a variety of abiotic plant stressors including HMM. However, little is known regarding the diversity and composition of AMF communities in heavy metal polluted sites in Ecuador. METHODS: In order to investigate the AMF diversity, root samples and associated soil of six plant species were collected from two sites polluted by heavy metals, located in Zamora-Chinchipe province, Ecuador. The AMF 18S nrDNA genetic region was analyzed and sequenced, and fungal OTUs were defined based on 99% sequence similarity. Results were contrasted with AMF communities from a natural forest and from reforestation sites located in the same province and with available sequences in GenBank. RESULTS: The main pollutants in soils were Pb, Zn, Hg, Cd and Cu with concentrations exceeding the soil reference value for agricultural use. Molecular phylogeny and OTU delimitation showed 19 OTUs, the family Glomeraceae was the most OTU-rich followed by Archaeosporaceae, Acaulosporaceae, Ambisporaceae and Paraglomeraceae. Most of the OTUs (11 of 19) have been found at other locations worldwide, 14 OTUs were proven from nearby non-contaminated sites in Zamora-Chinchipe. CONCLUSION: Our study showed that there are no specialized OTUs at the studied HMM polluted sites, but rather generalists adapted to a wide variety of habitats. Their potential role in phytoremediation approaches remains to be investigated.


Subject(s)
Glomeromycota , Metals, Heavy , Mycorrhizae , Soil Pollutants , Mycorrhizae/genetics , Gold , Ecuador , Metals, Heavy/toxicity , Glomeromycota/genetics , Soil , Plants , Mining , Plant Roots/microbiology , Soil Pollutants/analysis , Soil Microbiology , Fungi/genetics
2.
New Phytol ; 227(5): 1505-1518, 2020 09.
Article in English | MEDLINE | ID: mdl-32368801

ABSTRACT

Anthropogenic atmospheric deposition can increase nutrient supply in the most remote ecosystems, potentially affecting soil biodiversity. Arbuscular mycorrhizal fungal (AMF) communities rapidly respond to simulated soil eutrophication in tropical forests. Yet the limited spatio-temporal extent of such manipulations, together with the often unrealistically high fertilization rates employed, impedes generalization of such responses. We sequenced mixed root AMF communities within a seven year-long fully factorial nitrogen (N) and phosphorus (P) addition experiment, replicated at three tropical montane forests in southern Ecuador with differing environmental characteristics. We hypothesized: strong shifts in community composition and species richness after long-term fertilization, site- and clade-specific responses to N vs P additions depending on local soil fertility and clade life history traits respectively. Fertilization consistently shifted AMF community composition across sites, but only reduced richness of Glomeraceae. Compositional changes were mainly driven by increases in P supply while richness reductions were observed only after combined N and P additions. We conclude that moderate increases of N and P exert a mild but consistent effect on tropical AMF communities. To predict the consequences of these shifts, current results need to be supplemented with experiments that characterize local species-specific AMF functionality.


Subject(s)
Mycorrhizae , Ecosystem , Ecuador , Forests , Fungi , Phosphorus , Plant Roots , Soil , Soil Microbiology
3.
Mycorrhiza ; 27(3): 225-232, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27882467

ABSTRACT

In epiphytic orchids, distinctive groups of fungi are involved in the symbiotic association. However, little is known about the factors that determine the mycorrhizal community structure. Here, we analyzed the orchid mycorrhizal fungi communities associated with three sympatric Cymbidieae epiphytic tropical orchids (Cyrtochilum flexuosum, Cyrtochilum myanthum, and Maxillaria calantha) at two sites located within the mountain rainforest of southern Ecuador. To characterize these communities at each orchid population, the ITS2 region was analyzed by Illumina MiSeq technology. Fifty-five mycorrhizal fungi operational taxonomic units (OTUs) putatively attributed to members of Serendipitaceae, Ceratobasidiaceae and Tulasnellaceae were identified. Significant differences in mycorrhizal communities were detected between the three sympatric orchid species as well as among sites/populations. Interestingly, some mycorrhizal OTUs overlapped among orchid populations. Our results suggested that populations of studied epiphytic orchids have site-adjusted mycorrhizal communities structured around keystone fungal species. Interaction with multiple mycorrhizal fungi could favor orchid site occurrence and co-existence among several orchid species.


Subject(s)
Mycorrhizae/classification , Mycorrhizae/isolation & purification , Orchidaceae/microbiology , Sequence Analysis, DNA/methods , Biodiversity , DNA, Fungal/analysis , Ecuador , Mycorrhizae/genetics , Orchidaceae/classification , Phylogeny , Plant Roots/microbiology , Species Specificity , Symbiosis
4.
Medicina (B Aires) ; 76(6): 338-342, 2016.
Article in Spanish | MEDLINE | ID: mdl-27959840

ABSTRACT

Organizing pneumonia is a clinical entity asociated with nonspecific symptoms and radiological findings and abnormalities in pulmonary function tests. It is defined by the characteristic histopathological pattern: filling of alveoli and respiratory bronchioles by plugs of granulation tissue. It can be idiopathic (COP) or secondary to other causes (SOP). It is an unusual finding and the clinical and radiographic findings are nonspecific. For specific diagnosis an invasive procedure has to be done, but often empirical treatment is started when there's a clinical suspicion. We describe the clinical characteristics of 13 patients with histological diagnosis of organizing pneumonia. Data was obtained from their medical records. The median age was 76 years and the median time to diagnosis from the onset of symptoms was 31 days. In 10 cases the diagnosis was made by transbronchial biopsy. 8 patients required hospitalization, 4 of them received high doses of steroids and 3 required ventilatory support. One patient died from a cause attributable to this entity and 5 relapsed. Dyspnea, cough and fever were the most frequent symptoms. Most patients had more than one tomographic pattern being the most common ground glass opacities and alveolar consolidation. Nine patients were diagnosed with COP and 4 with SOP. The most frequent underlying cause of SOP was drug toxicity. The clinical characteristics of the reported cases are consistent with previously published series. As an interesting feature, there was a group of patients that needed high doses of steroids and ventilatory support.


Subject(s)
Cryptogenic Organizing Pneumonia/pathology , Lung/pathology , Adrenal Cortex Hormones/therapeutic use , Adult , Aged , Aged, 80 and over , Biopsy , Cough/etiology , Cryptogenic Organizing Pneumonia/complications , Cryptogenic Organizing Pneumonia/diagnostic imaging , Cryptogenic Organizing Pneumonia/drug therapy , Dyspnea/etiology , Female , Fever/etiology , Humans , Lung/diagnostic imaging , Male , Middle Aged , Thoracoscopy , Tomography, X-Ray Computed , Treatment Outcome , Young Adult
5.
Microb Ecol ; 69(3): 652-67, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25339308

ABSTRACT

Food security (a pressing issue for all nations) faces a threat due to population growth, land availability for growing crops, a changing climate (leading to increases in both abiotic and biotic stresses), heightened consumer awareness of the risks related to the use of agrichemicals, and also the reliance on depleting fossil fuel reserves for their production. Legislative changes in Europe mean that fewer agrichemicals will be available in the future for the control of crop pests and pathogens. The need for the implementation of a more sustainable agricultural system globally, incorporating an integrated approach to disease management, has never been more urgent. To that end, the Valorizing Andean Microbial Diversity (VALORAM) project (http://valoram.ucc.ie), funded under FP7, examined the role of microbial communities in crop production and protection to improve the sustainability, food security, environmental protection, and productivity for rural Andean farmers. During this work, microbial volatile organic compounds (mVOCs) of 27 rhizobacterial isolates were identified using gas chromatography/mass spectrometry (GC/MS), and their antifungal activity against Rhizoctonia solani was determined in vitro and compared to the activity of a selection of pure volatile compounds. Five of these isolates, Pseudomonas palleroniana R43631, Bacillus sp. R47065, R47131, Paenibacillus sp. B3a R49541, and Bacillus simplex M3-4 R49538 trialled in the field in their respective countries of origin, i.e., Bolivia, Peru, and Ecuador, showed significant increase in the yield of potato. The strategy followed in the VALORAM project may offer a template for the future isolation and determination of putative biocontrol and plant growth-promoting agents, useful as part of a low-input integrated pest management system.


Subject(s)
Bacteria/chemistry , Mycorrhizae/chemistry , Soil Microbiology , Solanum tuberosum/growth & development , Solanum tuberosum/microbiology , Volatile Organic Compounds/pharmacology , Bacteria/isolation & purification , Bolivia , Ecuador , Fungicides, Industrial/isolation & purification , Fungicides, Industrial/pharmacology , Gas Chromatography-Mass Spectrometry , Peru , Plant Roots/chemistry , Plant Roots/microbiology , Rhizoctonia/drug effects , Solanum tuberosum/chemistry , Solid Phase Microextraction , Volatile Organic Compounds/isolation & purification
6.
Molecules ; 20(10): 18047-65, 2015 Oct 01.
Article in English | MEDLINE | ID: mdl-26437395

ABSTRACT

Non-targeted ¹H-NMR methods were used to determine metabolite profiles from crude extracts of Alpine and Ecuadorian lichens collected from their natural habitats. In control experiments, the robustness of metabolite detection and quantification was estimated using replicate measurements of Stereocaulon alpinum extracts. The deviations in the overall metabolite fingerprints were low when analyzing S. alpinum collections from different locations or during different annual and seasonal periods. In contrast, metabolite profiles observed from extracts of different Alpine and Ecuadorian lichens clearly revealed genus- and species-specific profiles. The discriminating functions determining cluster formation in principle component analysis (PCA) were due to differences in the amounts of genus-specific compounds such as sticticin from the Sticta species, but also in the amounts of ubiquitous metabolites, such as sugar alcohols or trehalose. However, varying concentrations of these metabolites from the same lichen species e.g., due to different environmental conditions appeared of minor relevance for the overall cluster formation in PCA. The metabolic clusters matched phylogenetic analyses using nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) sequences of lichen mycobionts, as exemplified for the genus Sticta. It can be concluded that NMR-based non-targeted metabolic profiling is a useful tool in the chemo-taxonomy of lichens. The same approach could also facilitate the discovery of novel lichen metabolites on a rapid and systematical basis.


Subject(s)
Lichens/chemistry , Metabolomics/methods , Plant Extracts/analysis , Proton Magnetic Resonance Spectroscopy/methods , Ascomycota/chemistry , Ascomycota/classification , DNA, Ribosomal/analysis , Lichens/classification , Lichens/genetics , Phylogeny , Plant Extracts/chemistry , Principal Component Analysis , Species Specificity
7.
Mycologia ; 106(4): 708-22, 2014.
Article in English | MEDLINE | ID: mdl-24874921

ABSTRACT

Delimitation of species and the search for a proper threshold for defining phylogenetic species in fungi are under discussion. In this study, morphological and molecular data are correlated to delimit species of Tulasnella, the most important mycobionts of Orchidaceae, which suffer from poor taxonomy. Resupinate basidiomata of Tulasnella species were collected in Ecuador and Germany, and 11 specimens (seven from Ecuador, four from Germany) were assigned to traditional species concepts by use of morphological keys. The specimens were compared by micro-anatomical examination with 75 specimens of Tulasnella borrowed from fungaria to obtain better insights on variation of characters. Sequences of the ITS region (127) were obtained after cloning from the fresh basidiomata and from pure cultures. Proportional variability of ITS sequences was analyzed within and among the cultures and the specimens designated to different morphospecies. Results suggested an intragenomic variation of less than 2%, an intraspecific variation of up to 4% and an interspecific divergence of more than 9% in Tulasnella. Cryptic species in Tulasnella, mostly from Ecuador, were revealed by phylogenetic analyses with 4% intraspecific divergence as a minimum threshold for delimiting species. Conventional diagnostic morphological characters appeared insufficient for species characterization. Arguments are presented for molecular delimitation of the established species Tulasnella albida, T. asymmetrica, T. eichleriana, T. cf. pinicola, T. tomaculum and T. violea.


Subject(s)
Basidiomycota/genetics , Orchidaceae/microbiology , Base Sequence , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Ecuador , Germany , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , Spores, Fungal , Trees
8.
Medicina (B Aires) ; 74(5): 393-6, 2014.
Article in Spanish | MEDLINE | ID: mdl-25347903

ABSTRACT

Inflammatory myopathies comprise a heterogeneous group of subacute, chronic and sometimes acute acquired muscle diseases. The most common inflammatory myopathies seen in practice can be separated into four distinct subsets: polymyositis, dermatomyositis, necrotizing autoimmune myositis and inclusion body myositis. These disorders present as proximal and symmetric muscle weakness but rarely respiratory muscles may also be affected. We report the case of a 39 year-old female with inflammatory myopathy with acute respiratory failure due to alveolar hypoventilation secondary to respiratory muscle dysfunction that required mechanical ventilation. The treatment with steroids, methotrexate and intravenous immune globulin was successful as well as the implementation of non-invasive ventilation as an alternative to endotracheal intubation.


Subject(s)
Arthritis, Rheumatoid/complications , Myositis/immunology , Respiratory Insufficiency/etiology , Respiratory Muscles/pathology , Adult , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Biopsy , Deltoid Muscle/pathology , Female , Humans , Immunoglobulins, Intravenous/therapeutic use , Myositis/drug therapy , Noninvasive Ventilation , Respiratory Insufficiency/therapy
9.
Am J Bot ; 100(12): 2339-48, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24252216

ABSTRACT

PREMISE OF THE STUDY: The presence of compatible fungi is necessary for epiphytic orchid recruitment. Thus, identifying associated mycorrhizal fungi at the population level is essential for orchid conservation. Recruitment patterns may also be conditioned by factors such as seed dispersal range and specific environmental characteristics. METHODS: In a forest plot, all trees with a diameter at breast height >1 cm and all individuals of the epiphytic orchid Epidendrum rhopalostele were identified and mapped. Additionally, one flowering individual of E. rhopalostele per each host tree was randomly selected for root sampling and DNA extraction. KEY RESULTS: A total of 239 E. rhopalostele individuals were located in 25 of the 714 potential host trees. Light microscopy of sampled roots showed mycorrhizal fungi in 22 of the 25 sampled orchids. Phylogenetic analysis of ITS1-5.8S-ITS2 sequences yielded two Tulasnella clades. In four cases, plants were found to be associated with both clades. The difference between univariate and bivariate K functions was consistent with the random labeling null model at all spatial scales, indicating that trees hosting clades A and B of Tulasnella are not spatially segregated. The analysis of the inhomogenous K function showed that host trees are not clustered, suggesting no limitations to population-scale dispersal. χ(2) analysis of contingency tables showed that E. rhopalostele is more frequent on dead trees than expected. CONCLUSIONS: EPIDENDRUM RHOPALOSTELE establishes mycorrhizal associations with at least two different Tulasnella species. The analysis of the distribution patterns of this orchid suggests a microsite preference for dead trees and no seed dispersal limitation.


Subject(s)
Basidiomycota/genetics , Ecosystem , Mycorrhizae , Orchidaceae , Phylogeny , Plant Roots/microbiology , Trees , Base Sequence , Basidiomycota/classification , DNA, Fungal , DNA, Ribosomal Spacer , Orchidaceae/growth & development , Orchidaceae/microbiology , Plant Dispersal , Sequence Analysis, DNA , Species Specificity , Symbiosis
10.
J Fungi (Basel) ; 9(9)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37755002

ABSTRACT

BACKGROUND: The delimitation of species of Tulasnella has been extensively studied, mainly at the morphological (sexual and asexual states) and molecular levels-showing ambiguity between them. An integrative species concept that includes characteristics such as molecular, ecology, morphology, and other information is crucial for species delimitation in complex groups such as Tulasnella. OBJECTIVES: The aim of this study is to test evolutionary relationships using a combination of alignment-based and alignment-free distance matrices as an alternative molecular tool to traditional methods, and to consider the secondary structures and CBCs from ITS2 (internal transcribed spacer) sequences for species delimitation in Tulasnella. METHODOLOGY: Three phylogenetic approaches were plotted: (i) alignment-based, (ii) alignment-free, and (iii) a combination of both distance matrices using the DISTATIS and pvclust libraries from an R package. Finally, the secondary structure consensus was modeled by Mfold, and a CBC analysis was obtained to complement the species delimitation using 4Sale. RESULTS AND CONCLUSIONS: The phylogenetic tree results showed delimited monophyletic clades in Tulasnella spp., where all 142 Tulasnella sequences were divided into two main clades A and B and assigned to seven species (T. asymmetrica, T. andina, T. eichleriana ECU6, T. eichleriana ECU4 T. pinicola, T. violea), supported by bootstrap values from 72% to 100%. From the 2D secondary structure alignment, three types of consensus models with helices and loops were obtained. Thus, T. albida belongs to type I; T. eichleriana, T. tomaculum, and T. violea belong to type II; and T. asymmetrica, T. andina, T. pinicola, and T. spp. (GER) belong to type III; each type contains four to six domains, with nine CBCs among these that corroborate different species.

11.
J Fungi (Basel) ; 9(1)2022 Dec 29.
Article in English | MEDLINE | ID: mdl-36675874

ABSTRACT

Bacterial resistance to antibiotics is a serious public health problem that needs new antibacterial compounds for control. Fungi, including resupinated fungi, are a potential source to discover new bioactive compounds efficient again to bacteria resistant to antibiotics. The inhibitory capacity against the bacterial species was statistically evaluated. All the species (basidiomata and strains) were molecularly characterized with the ITS1-5.8S-ITS2 barcoding marker. The strains Ceraceomyces sp., Fuscoporia sp., Gloeocystidiellum sp., Oliveonia sp., Phanerochaete sp., and Xenasmatella sp. correspond to resupinate Basidiomycetes, and only the strain Hypocrea sp. is an Ascomycete, suggesting contamination to the basidiome of Tulasnella sp. According to the antagonistic test, only the Gloeocystidiellum sp. strain had antibacterial activity against the bacterial species Escherichia coli of clinical interest. Statistically, Gloeocystidiellum sp. was significantly (<0.001) active against two E. coli pathotypes (O157:H7 and ATCC 25922). Contrarily, the antibacterial activity of fungi against other pathotypes of E. coli and other strains such as Serratia sp. was not significant. The antibacterial activity between 48 and 72 h increased according to the measurement of the inhibition halos. Because of this antibacterial activity, Gloeocystidiellum sp. was taxonomically studied in deep combined morphological and molecular characterization (ITS1-5.8S-ITS2; partial LSU D1/D2 of nrDNA). A new species Gloeocystidiellum lojanense, a resupinate and corticioid fungus from a tropical montane rainforest of southern Ecuador, with antibacterial potential against E. coli, is proposed to the science.

12.
Environ Microbiol Rep ; 14(5): 775-784, 2022 10.
Article in English | MEDLINE | ID: mdl-36085412

ABSTRACT

Root associated fungal (RAF) communities can exert strong effects on plant communities and are potentially sensitive to shifts in soil fertility. As increased atmospheric nitrogen (N) and phosphorus (P) deposition can alter the nutrient balance in natural ecosystems, we assessed the response of RAF communities to a fertilization experiment deployed on a highly diverse Andean forest. The stand level fine root fraction was sampled after 7 years of systematic N and P additions and RAF communities were characterized by a deep sequencing approach. We expected that fertilization will enhance competition of fungal taxa for limiting nutrients, thus eliciting diversity reductions and alterations in the structure of RAF communities. Fertilization treatments did not reduce RAF richness but affected community composition. At the phylum level fertilization reduced richness exclusively among Glomeromycota. In contrast, N and P additions (alone or in combination) altered the composition of several fungal phyla. The lack of a generalized response to long-term fertilization among RAF lineages suggests that most of these lineages will not be directly and immediately affected by the increasing rates of atmospheric N and P deposition expected for this region by 2050.


Subject(s)
Nitrogen , Phosphorus , Ecosystem , Forests , Nitrogen/analysis , Plant Roots/microbiology , Soil/chemistry , Soil Microbiology
13.
Proc Biol Sci ; 277(1685): 1289-98, 2010 Apr 22.
Article in English | MEDLINE | ID: mdl-20007181

ABSTRACT

Distinctive groups of fungi are involved in the diverse mycorrhizal associations of land plants. All previously known mycorrhiza-forming Basidiomycota associated with trees, ericads, liverworts or orchids are hosted in Agaricomycetes, Agaricomycotina. Here we demonstrate for the first time that Atractiellomycetes, members of the 'rust' lineage (Pucciniomycotina), are mycobionts of orchids. The mycobionts of 103 terrestrial and epiphytic orchid individuals, sampled in the tropical mountain rainforest of Southern Ecuador, were identified by sequencing the whole ITS1-5.8S-ITS2 region and part of 28S rDNA. Mycorrhizae of 13 orchid individuals were investigated by transmission electron microscopy. Simple septal pores and symplechosomes in the hyphal coils of mycorrhizae from four orchid individuals indicated members of Atractiellomycetes. Molecular phylogeny of sequences from mycobionts of 32 orchid individuals out of 103 samples confirmed Atractiellomycetes and the placement in Pucciniomycotina, previously known to comprise only parasitic and saprophytic fungi. Thus, our finding reveals these fungi, frequently associated to neotropical orchids, as the most basal living basidiomycetes involved in mycorrhizal associations of land plants.


Subject(s)
Mycorrhizae/genetics , Mycorrhizae/physiology , Orchidaceae/microbiology , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Ecuador , Mycorrhizae/classification , Mycorrhizae/ultrastructure , Phylogeny
14.
Clin Nucl Med ; 45(2): e122-e124, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31714280

ABSTRACT

Immunoglobulin G4-related disease (IgG4-RD) is a systemic inflammatory condition that can manifest in atypical locations. We present the case of a middle-aged woman presenting with isolated IgG4-RD of left maxilla and nasal septum, confirmed with F-FDG PET/CT. She achieved complete metabolic response with multiple pharmacologic treatment, but 1 year later, she experienced local relapse, and FDG PET/CT found new additional lesions in humeral vasculature and lungs. This case illustrates the usefulness of FDG PET/CT for initial evaluation and monitoring of IgG4-RD with unusual nasomaxillary involvement.


Subject(s)
Fluorodeoxyglucose F18 , Immunoglobulin G4-Related Disease/diagnostic imaging , Maxilla/diagnostic imaging , Nasal Septum/diagnostic imaging , Positron Emission Tomography Computed Tomography , Female , Follow-Up Studies , Humans , Middle Aged , Recurrence
15.
PLoS One ; 14(8): e0221091, 2019.
Article in English | MEDLINE | ID: mdl-31419262

ABSTRACT

Arbuscular mycorrhizal fungi (AMF) are the most prominent mycobionts of plants in the tropics, yet little is known about their diversity, species compositions and factors driving AMF distribution patterns. To investigate whether elevation and associated vegetation type affect species composition, we sampled 646 mycorrhizal samples in locations between 1000 and 4000 m above sea level (masl) in the South of Ecuador. We estimated diversity, distribution and species compositions of AMF by cloning and Sanger sequencing the 18S rDNA (the section between AML1 and AML2) and subsequent derivation of fungal OTUs based on 99% sequence similarity. In addition, we analyzed the phylogenetic structure of the sites by computing the mean pairwise distance (MPD) and the mean nearest taxon difference (MNTD) for each elevation level. It revealed that AMF species compositions at 1000 and 2000 masl differ from 3000 and 4000 masl. Lower elevations (1000 and 2000 masl) were dominated by members of Glomeraceae, whereas Acaulosporaceae were more abundant in higher elevations (3000 and 4000 masl). Ordination of OTUs with respect to study sites revealed a correlation to elevation with a continuous turnover of species from lower to higher elevations. Most of the abundant OTUs are not endemic to South Ecuador. We also found a high proportion of rare OTUs at all elevations: 79-85% of OTUs occurred in less than 5% of the samples. Phylogenetic community analysis indicated clustering and evenness for most elevation levels indicating that both, stochastic processes and habitat filtering are driving factors of AMF community compositions.


Subject(s)
Altitude , Mycobiome/genetics , Mycorrhizae/genetics , Plant Roots/microbiology , Soil Microbiology , DNA, Fungal/isolation & purification , DNA, Ribosomal/genetics , Ecuador , Forests , Mycorrhizae/isolation & purification , Phylogeny
16.
Front Plant Sci ; 9: 1664, 2018.
Article in English | MEDLINE | ID: mdl-30505314

ABSTRACT

Orchids are known for their vast diversity and dependency on mycorrhizal fungi. Under in situ conditions, the biotic and abiotic factors determining the composition and distribution of orchid mycorrhizal fungi (OMF) communities remain largely unexplored. Therefore in situ experiments are needed to better understand the interactions between orchids and fungi. A seedling-trap experiment was conducted in the Reserva Biológica San Francisco, a well-known biodiversity hotspot located in the Andes of southern Ecuador. The objective was to investigate the effect of orchid species, site, elevation or temporal variation on the assembly and structure of OMF associated with Cyrtochilum retusum and Epidendrum macrum. The OMF community composition was determined using the Illumina MiSeq sequencing of the internal transcribed spacer 2 (ITS2) region. The results exhibited 83 OMF operational taxonomic units belonging to Tulasnellaceae, Ceratobasidiaceae, Serendipitaceae and Atractiellales. It was observed that the composition of the OMF communities was different among orchid species and temporal variation but was not different among sites. The results further support that orchids have a core of keystone OMF that are ubiquitously distributed and stable across temporal change, whereas the majority of these fungi are randomly associated with the plants.

17.
Oncol Rep ; 15(4): 1091-1100, 2006.
Article in English | MEDLINE | ID: mdl-16525707

ABSTRACT

TENPET (Trans European Network for Positron Emission Tomography) aims to evaluate the provision of integrated teleconsultation and intelligent computer supported cooperative work services for clinical positron emission tomography (PET) in Europe at its current stage, as it is a multi-centre project financially supported by the European Commission (Information Society, eTEN Program). It addresses technological challenges by linking PET centres and developing supporting services that permit remote consultation between professionals in the field. The technological platform (CE-marked) runs on Win2000/NT/XP systems and incorporates advanced techniques for image visualization, analysis and fusion, as well as for interactive communication and message handling for off-line communications. Four PET Centres from Spain, France and Germany participate to the pilot system trials. The performance evaluation of the system is carried out via log files and user-filled questionnaires on the frequency of the teleconsultations, their duration and efficacy, quality of the images received, user satisfaction, as well as on privacy, ethical and security issues. TENPET promotes the co-operation and improved communication between PET practitioners that are miles away from their peers or on mobile units, offering options for second opinion and training and permitting physicians to remotely consult patient data if they are away from their centre. It is expected that TENPET will have a significant impact in the development of new skills by PET professionals and will support the establishment of peripheral PET units. To our knowledge, TENPET is the first telemedicine service specifically designed for oncological PET. This report presents the technical innovations incorporated in the TENPET platform and the initial pilot studies at real and diverse clinical environments in the field of oncology.


Subject(s)
Medical Oncology/trends , Positron-Emission Tomography , Remote Consultation , Artificial Intelligence , Communication , Computer Security , Confidentiality , Europe , Humans , Neoplasms/diagnostic imaging
18.
Indian J Nucl Med ; 31(2): 156-7, 2016.
Article in English | MEDLINE | ID: mdl-27095871

ABSTRACT

Femoroacetabular impingement (FAI) is a structural abnormality of proximal femur and/or acetabulum. It has been recently described, and there are limited reports in nuclear medicine literature because bone scintigraphy is not listed in its diagnostic protocol, but it should be included on differential diagnosis when evaluating patients, with hip-related symptoms because it may be misinterpreted as degenerative changes or avascular necrosis, and its early treatment avoid progression to osteoarthritis. We describe the case of a male who suffered from hip pain. Bone planar scintigraphic appearance mimicked avascular necrosis, but single photon emission computed tomography (CT) imaging and CT examination confirmed the diagnosis of FAI.

19.
Rev. nefrol. diál. traspl ; Rev. nefrol. diál. traspl. (En línea);41(1): 21-30, mar. 2021. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1377118

ABSTRACT

RESUMEN Introducción: La insuficiencia renal aguda en pacientes internados en unidades de terapia intensiva es frecuente y se asocia con alta mortalidad. El objetivo del trabajo fue identificarfactores relacionados con mortalidad en pacientes internados en unidades de terapia intensiva con insuficiencia renal aguda que requirieron tratamiento sustitutivo de la función renal.Material y métodos:Se identificaron, en forma retrospectiva, 3.732pacientes internados en unidades de terapia intensiva. El 2,7% presentaron insuficiencia renal aguda con requerimiento de tratamiento sustitutivo de la función renal. Se excluyeron pacientes con antecedentes de enfermedad renal crónica con filtrado glomerular menor de 15 ml/m o en diálisis crónica. Resultados:Se analizaron 97 casos, 55% mujeres, mediana de edad 74 años (rango intercuartil: 68-78). Los motivos de insuficiencia renal aguda más frecuentes fueron sepsis (41,2%) y necrosis tubular aguda isquémica (36,1%). El 22,7% eran diabéticos. La mediana de APACHE II fue 23 (rango intercuartil: 19-28). El 75,3% requirió asistencia respiratoria mecánica y el 81,4%, inotrópicos. La mediana de tiempo de internación en unidades de terapia intensiva fue de 8 días (rango intercuartil: 4-11) y la mortalidad fue 58,76%.En el análisis individual, la mortalidad se asoció con asistencia respiratoria mecánica (p<0,0001), el uso de inotrópicos (p<0,0001) y el antecedente deenfermedad renal crónica (p=0.008), pero no se encontró asociación con sexo, edad, APACHE II, diabetes ni otros factores de riesgo cardiovascular. Modelo multivariable de factores asociados con mortalidad: asistencia respiratoria mecánica (Odds Ratio=14,16; p=0,003), inotrópicos (Odds Ratio=8,73; p=0,07) y enfermedad renal crónica (Odds Ratio=0,27; p=0,020).Conclusiones:Los pacientes con insuficiencia renal agudaque requirieron tratamiento sustitutivo de la función renal ingresados a unidades de terapia intensiva presentaron alta mortalidad. El requerimiento de asistencia respiratoria mecánica se asoció con mayor mortalidad, también el uso de inotrópicos, aunque no alcanzó significación estadística en el multivariable. El antecedente de enfermedad renal crónica se asoció con menor mortalidad.


ABSTRACT Introduction: Acute renal failure in patients admitted to intensive care units is common and is associated with high mortality. The aim of the study was to identify factors related to mortality in patients with acute renal failure, hospitalized in intensive care units, who required renal replacement therapy. Methods: We retrospectively identified 3,732 patients admitted to intensive care units; 2.7% had acute renal failure requiring replacement therapy for renal function. Patients with a history of chronic kidney disease with a glomerular filtration rate of less than 15 mL/m or on chronic dialysis were excluded. Results: 97 cases were analyzed, 55% women, median age: 74 years (interquartile range: 68-78). The most frequent reasons for acute renal failure were sepsis (41.2%) and ischemic acute tubular necrosis (36.1%); 22.7% were diabetic. The median APACHE II score was 23 (interquartile range: 19-28). 75.3% required mechanical ventilation and 81.4%, inotropic drugs. Median time of hospitalization in intensive care units was 8 days (interquartile range: 4-11) and the mortality rate was 58.76%. In the individual analysis, mortality was associated with mechanical ventilation (p<0.0001), the use of inotropic drugs (p<0.0001) and a history of chronic kidney disease (p=0.008), but no association was found with sex, age, APACHE II score, diabetes, or other cardiovascular risk factors. Multivariate model of factors associated with mortality: mechanical ventilation (Odds Ratio=14.16; p=0.003), inotropic drugs (Odds Ratio=8.73; p=0.07) and chronic kidney disease (Odds Ratio=0.27; p=0.020). Conclusions: Patients with acute renal failure who required renal replacement therapy and were admitted to intensive care units presented high mortality. The requirement for mechanical ventilation was associated with higher mortality, as was the use of inotropic drugs, although it did not reach statistical significance in the multivariate analysis. A history of chronic kidney disease was associated with lower mortality.

20.
Plant Signal Behav ; 10(2): e988076, 2015.
Article in English | MEDLINE | ID: mdl-25723847

ABSTRACT

Colonization of plant rhizosphere/roots by beneficial microorganisms (e.g. plant growth promoting rhizobacteria - PGPR, arbuscular mycorrhizal fungi - AMF) confers broad-spectrum resistance to virulent pathogens and is known as induced systemic resistance (ISR) and mycorrhizal-induced resistance (MIR). ISR or MIR, an indirect mechanism for biocontrol, involves complex signaling networks that are regulated by several plant hormones, the most important of which are salicylic acid (SA), jasmonic acid (JA) and ethylene (ET). In the present study, we investigated if inoculation of potato plantlets with an AMF (Rhizophagus irregularis MUCL 41833) and a PGPR (Pseudomonas sp R41805) either alone or in combination, could elicit host defense response genes in the presence or absence of Rhizoctonia Solani EC-1, a major potato pathogen. RT-qPCR revealed the significant expression of ethylene response factor 3 (EFR3) in mycorrhized potato plantlets inoculated with Pseudomonas sp R41805 and also in mycorrhized potato plantlets inoculated with Pseudomonas sp R41805 and challenged with R. solani. The significance of ethylene response factors (ERFs) in pathogen defense has been well documented in the literature. The results of the present study suggest that the dual inoculation of potato with PGPR and AMF may play a part in the activation of plant systemic defense systems via ERF3.


Subject(s)
Ethylenes/metabolism , Glomeromycota/physiology , Plant Proteins/metabolism , Pseudomonas/physiology , Solanum tuberosum/immunology , Solanum tuberosum/microbiology , Gene Expression Regulation, Plant , Mycorrhizae/physiology , Plant Proteins/genetics , Solanum tuberosum/genetics
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