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1.
J Dr Nurs Pract ; 2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33468613

ABSTRACT

BACKGROUND: Heart failure (HF) is a chronic condition associated with high rates of hospital readmissions. The prevalence and costs of HF are expected to rise dramatically by 2030 (Heidenreich,et al., 2013). OBJECTIVE: A 24-month, retrospective study was conducted using electronic medical record (EMR) chart review, seeking to identify if postdischarge follow-up phone calls decreased 30-day readmissions in individuals with HF. METHODS: The study included 705 adult participants who were admitted to the hospital for HF. Some received a postdischarge call within 2 business days of discharge, and some did not. RESULTS: Participants who received the postdischarge call were less likely to be readmitted (20.1%) than participants who did not receive a postdischarge call (28.8%; p = .007). Participants who received the postdischarge call were more likely to have a follow-up visit within 14 days (70.1%) than participants who did not receive a postdischarge call (30.2%; p < .001). CONCLUSIONS: The findings from this study may help to drive future transitional care strategies for individuals diagnosed with HF. IMPLICATIONS FOR NURSING: Nurse-led transitional care interventions offer potential solutions to ensure safe, effective hospital discharges.

2.
Blood ; 137(20): 2817-2826, 2021 05 20.
Article in English | MEDLINE | ID: mdl-33259589

ABSTRACT

Intolerance is the most common reason for kinase inhibitor (KI) discontinuation in chronic lymphocytic leukemia (CLL). Umbralisib, a novel highly selective phosphatidylinositol 3-kinase Î´ (PI3Kδ)/CK1ε inhibitor, is active and well tolerated in CLL patients. In this phase 2 trial (NCT02742090), umbralisib was initiated at 800 mg/d in CLL patients requiring therapy, who were intolerant to prior BTK inhibitor (BTKi) or PI3K inhibitor (PI3Ki) therapy, until progression or toxicity. Primary end point was progression-free survival (PFS). Secondary end points included time to treatment failure and safety. DNA was genotyped for CYP3A4, CYP3A5, and CYP2D6 polymorphisms. Fifty-one patients were enrolled (44 BTKi intolerant and 7 PI3Kδi intolerant); median age was 70 years (range, 48-96), with a median of 2 prior lines of therapy (range, 1-7), 24% had del17p and/or TP53 mutation, and 65% had unmutated IGHV. Most common adverse events (AEs) leading to prior KI discontinuation were rash (27%), arthralgia (18%), and atrial fibrillation (16%). Median PFS was 23.5 months (95% CI, 13.1-not estimable), with 58% of patients on umbralisib for a longer duration than prior KI. Most common (≥5%) grade ≥3 AEs on umbralisib (all causality) were neutropenia (18%), leukocytosis (14%), thrombocytopenia (12%), pneumonia (12%), and diarrhea (8%). Six patients (12%) discontinued umbralisib because of an AE. Eight patients (16%) had dose reductions and were successfully rechallenged. These are the first prospective data to confirm that switching from a BTKi or alternate PI3Ki to umbralisib in this BTKi- and PI3Ki-intolerant CLL population can result in durable well-tolerated responses.


Subject(s)
Antineoplastic Agents/therapeutic use , Class I Phosphatidylinositol 3-Kinases/antagonists & inhibitors , Heterocyclic Compounds, 4 or More Rings/therapeutic use , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Neoplasm Proteins/antagonists & inhibitors , Protein Kinase Inhibitors/therapeutic use , Adenine/adverse effects , Adenine/analogs & derivatives , Adenine/therapeutic use , Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Cardiovascular Diseases/chemically induced , Drug Eruptions/etiology , Drug Resistance, Neoplasm , Female , Gastrointestinal Diseases/chemically induced , Heterocyclic Compounds, 4 or More Rings/adverse effects , Humans , Kaplan-Meier Estimate , Leukemia, Lymphocytic, Chronic, B-Cell/enzymology , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Male , Middle Aged , Piperidines/adverse effects , Piperidines/therapeutic use , Progression-Free Survival , Protein Kinase Inhibitors/adverse effects
3.
J Dr Nurs Pract ; 13(2): 148-155, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32817504

ABSTRACT

BACKGROUND: Acute respiratory distress syndrome (ARDS) is characterized by an acute, diffuse, inflammatory lung injury, leading to increased alveolar capillary permeability, increased lung weight, and loss of aerated lung tissue (Fan, Brodie, & Slutsky, 2018). Primary treatment for ARDS is artificial mechanical ventilation (AMV) (Wu, Huang, Wu, Wang, & Lin, 2016). Given recent advances in technology, the use of veno-venous extracorporeal membrane oxygenation (VV-ECMO) to treat severe ARDS is growing rapidly (Combes et al., 2014). OBJECTIVE: This 49-month quantitative, retrospective inpatient EMR chart review compared if cannulation with VV-ECMO up to and including 48 hours of admission and diagnosis in adult patients 30 to 65 years of age diagnosed with ARDS, decreased duration on AMV, as compared to participants who were cannulated after 48 hours of admission and diagnosis with ARDS. METHODS: A total of 110 participants were identified as receiving VV-ECMO during the study timeframe. Of the 58 participants who met all inclusion criteria, 39 participants were cannulated for VV-ECMO within 48 hours of admission and diagnosis with ARDS, and 19 participants were cannulated with VV-ECMO after 48 hours of admission and diagnosis with ARDS. RESULTS: Data collected identified no statistically significant (p < 0.579) difference in length of days on AMV between participant groups. CONCLUSIONS: Further studies are needed to determine if earlier initiation of VV-ECMO in adult patients with ARDS decrease time on AMV. IMPLICATIONS FOR NURSING: Although the results related to length of time on AMV did not produce statistical significance, the decreased duration of AMV in the participants who were cannulated within 48 hours (21 days vs. 27 days) may support several benefits associated with this participant population including increased knowledge of healthcare providers, decreased lung injury, earlier discharge which decreases hospital and patient cost, ability for patients to communicate sooner, decreased risk of pulmonary infection, decreased length of stay, decreased cost, and improved patient and family satisfaction.


Subject(s)
Catheterization/methods , Extracorporeal Membrane Oxygenation/methods , Length of Stay/statistics & numerical data , Respiration, Artificial/methods , Respiration, Artificial/statistics & numerical data , Respiratory Distress Syndrome/therapy , Adult , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies , Time Factors
4.
Ann Plast Surg ; 74(2): 157-62, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25590251

ABSTRACT

BACKGROUND: The National Surgical Quality Improvement Program (NSQIP) and the Tracking Operations and Outcomes for Plastic Surgeons (TOPS) registries gather outcomes for plastic surgery procedures. The NSQIP collects hospital data using trained nurses, and the TOPS relies on self-reported data. We endeavored to compare the TOPS and NSQIP data sets with respect to cohort characteristics and outcomes to better understand the strengths and weakness of each registry as afforded by their distinct data collection methods. STUDY DESIGN: The 2008 to 2011 TOPS and NSQIP databases were queried for breast reductions and breast reconstructions. Propensity score matching identified similar cohorts from the TOPS and NSQIP databases. Shared 30-day surgical and medical complications rates were compared across matched cohorts. RESULTS: The TOPS captured a significantly greater number of wound dehiscence occurrences (4.77%-5.47% vs 0.69%-1.17%, all P<0.001), as well as more reconstructive failures after prosthetic reconstruction (2.82% vs 0.26%, P<0.001). Medical complications were greater in NSQIP (P<0.05). Other complication rates did not differ across any procedure (all P>0.05). CONCLUSIONS: The TOPS and NSQIP capture significantly different patient populations, with TOPS' self-reported data allowing for the inclusion of private practices. This self-reporting limits TOPS' ability to identify medical complications; surgical complications and readmissions, however, were not underreported. Many surgical complications are captured by TOPS at a higher rate due to its broader definitions, and others are not captured by NSQIP at all. The TOPS and NSQIP provide complementary information with different strengths and weakness that together can guide evidence-based decision making in plastic surgery.


Subject(s)
Mammaplasty , Postoperative Complications/epidemiology , Registries/standards , Adult , Cohort Studies , Female , Humans , Mammaplasty/methods , Mammaplasty/standards , Middle Aged , Outcome Assessment, Health Care , Propensity Score , Quality Improvement , Self Report , United States
5.
PLoS One ; 9(7): e103076, 2014.
Article in English | MEDLINE | ID: mdl-25072467

ABSTRACT

Pakaraimaea dipterocarpacea, a member of the Dipterocarpaceae endemic in the Guayana region, is associated with a diverse community of ectomycorrhizal (ECM) fungi. Amongst the 41 ECM fungal species detected in a 400 m2 P. dipterocarpacea ssp. nitida plot in Southern Venezuela, three species belonged to the Sebacinales. We tested whether ECM anatomotype characterization can be used as a feasible element in an integrative taxonomy in this diverse fungal group, where the relevance of fruitbody morphology for species delimitation seems limited. Using a combination of ECM morpho-anatomical characterizations and phylogenetic analyses based on nuclear ITS and LSU sequences, we report three new species. The main distinguishing features of Sebacina guayanensis are the yellowish cell walls together with conspicuous undifferentiated, uniform compact (type B) rhizomorphs. Staghorn-like hyphae are characteristic of S. tomentosa. The combination of clusters of thick-walled emanating hyphae, including hyphae similar to awl-shaped cystidia with basal dichotomous or trichotomous ramifications, and the presence of type B rhizomorphs were characteristic of a third, yet unnamed species. The three species belong to three different, possibly specifically tropical clades in Sebacinales Group A. The geographic distribution of phylogenetically related strains was wide, including a Dicymbe forest in Guyana and an Ecuadorian rainforest with Coccoloba species. We show that ECM morpho-anatomy can be used, in combination with other analyses, to delineate species within Sebacinales Group A. In addition to phylogenetic information, type B rhizomorphs observed in different Sebacinales clades have important ecological implications for this fungal group. The phylogeography of Sebacinales suggests that dispersion and host jump are important radiation mechanisms that shaped P. dipterocarpacea ECM fungal community. This study emphasizes the need for more sequence data to evaluate the hypothesis that phylogeographic relationships between neo- and paleotropical ECM fungal species could be attributed to the vicariance of cross-continental hosts such as the Dipterocarpacae.


Subject(s)
Basidiomycota/classification , Basidiomycota/genetics , Biodiversity , Dipterocarpaceae/microbiology , Phylogeny , Phylogeography , DNA, Fungal/genetics , Forests , Venezuela
6.
Mycorrhiza ; 20(3): 147-59, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19730896

ABSTRACT

Aneura pinguis (Aneuraceae) is a cosmopolitan thalloid liverwort that shows a specific mycorrhiza-like interaction with basidiomycetes. To date, tropical specimens have not been studied in great depth. Samples of A. pinguis were collected from 48 individuals in one plot in South Ecuador and 54 individuals in five European countries. Light and transmission electron microscopy and molecular analyses based on nuclear rDNA coding for the ribosomal large subunit (nucLSU) and from the 5.8s-ITS2 regions were carried out to identify the associated mycobionts and to study their phylogenetic relationships. Microscopic and ultrastructural investigations of the fungal colonisation showed a high congruence between the European and the Ecuadorian sites and confirmed previous results. Tulasnellales are the only mycobionts that could be detected from ultrastructural characters with certainty. Molecular phylogenetic analysis indicated the presence of tulasnelloid fungi from at least 13 distinct clades. The composition of the communities of tulasnelloid fungi in A. pinguis differs between Ecuador and Europe. The diversity of tulasnelloid fungal partners was much higher at the Ecuadorian site.


Subject(s)
Basidiomycota/classification , Basidiomycota/isolation & purification , Biodiversity , Hepatophyta/microbiology , Mycorrhizae/growth & development , Basidiomycota/cytology , Basidiomycota/genetics , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Ecuador , Europe , Microscopy , Microscopy, Electron, Transmission , Molecular Sequence Data , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNA
7.
BMC Evol Biol ; 9: 1, 2009 Jan 02.
Article in English | MEDLINE | ID: mdl-19121213

ABSTRACT

BACKGROUND: Section Calochroi is one of the most species-rich lineages in the genus Cortinarius (Agaricales, Basidiomycota) and is widely distributed across boreo-nemoral areas, with some extensions into meridional zones. Previous phylogenetic studies of Calochroi (incl. section Fulvi) have been geographically restricted; therefore, phylogenetic and biogeographic relationships within this lineage at a global scale have been largely unknown. In this study, we obtained DNA sequences from a nearly complete taxon sampling of known species from Europe, Central America and North America. We inferred intra- and interspecific phylogenetic relationships as well as major morphological evolutionary trends within section Calochroi based on 576 ITS sequences, 230 ITS + 5.8S + D1/D2 sequences, and a combined dataset of ITS + 5.8S + D1/D2 and RPB1 sequences of a representative subsampling of 58 species. RESULTS: More than 100 species were identified by integrating DNA sequences with morphological, macrochemical and ecological data. Cortinarius section Calochroi was consistently resolved with high branch support into at least seven major lineages: Calochroi, Caroviolacei, Dibaphi, Elegantiores, Napi, Pseudoglaucopodes and Splendentes; whereas Rufoolivacei and Sulfurini appeared polyphyletic. A close relationship between Dibaphi, Elegantiores, Napi and Splendentes was consistently supported. Combinations of specific morphological, pigmentation and molecular characters appear useful in circumscribing clades. CONCLUSION: Our analyses demonstrate that Calochroi is an exclusively northern hemispheric lineage, where species follow their host trees throughout their natural ranges within and across continents. Results of this study contribute substantially to defining European species in this group and will help to either identify or to name new species occurring across the northern hemisphere. Major groupings are in partial agreement with earlier morphology-based and molecular phylogenetic hypotheses, but some relationships were unexpected, based on external morphology. In such cases, their true affinities appear to have been obscured by the repeated appearance of similar features among distantly related species. Therefore, further taxonomic studies are needed to evaluate the consistency of species concepts and interpretations of morphological features in a more global context. Reconstruction of ancestral states yielded two major evolutionary trends within section Calochroi: (1) the development of bright pigments evolved independently multiple times, and (2) the evolution of abruptly marginate to flattened stipe bulbs represents an autapomorphy of the Calochroi clade.


Subject(s)
Cortinarius/genetics , Phylogeny , Cell Nucleus/genetics , Central America , Cortinarius/classification , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Europe , Evolution, Molecular , North America , Sequence Alignment , Sequence Analysis, DNA , Species Specificity
8.
New Phytol ; 174(4): 864-878, 2007.
Article in English | MEDLINE | ID: mdl-17504468

ABSTRACT

Previous reports of sequences of Sebacinales (basal Hymenomycetes) from ericoid mycorrhizas raised the question as to whether Sebacinales are common mycorrhizal associates of Ericaceae, which are usually considered to associate with ascomycetes. Here, we sampled 239 mycorrhizas from 36 ericoid mycorrhizal species across the world (Vaccinioideae and Ericoideae) and 361 mycorrhizas from four species of basal Ericaceae lineages (Arbutoideae and Monotropoideae) that do not form ericoid mycorrhizas, but ectendomycorrhizas. Sebacinales were detected using sebacinoid-specific primers for nuclear 28S ribosomal DNA, and some samples were investigated by transmission electron microscopy (TEM). Diverging Sebacinales sequences were recovered from 76 ericoid mycorrhizas, all belonging to Sebacinales clade B. Indeed, some intracellular hyphal coils had ultrastructural TEM features expected for Sebacinales, and occurred in living cells. Sebacinales belonging to clade A were found on 13 investigated roots of the basal Ericaceae, and TEM revealed typical ectendomycorrhizal structures. Basal Ericaceae lineages thus form ectendomycorrhizas with clade A Sebacinales, a clade that also harbours ectomycorrhizal fungi. This further supports the proposition that Ericaceae ectendomycorrhizas involve ectomycorrhizal fungal taxa. When ericoid mycorrhizas evolved secondarily in Ericaceae, a shift of mycobionts occurred to ascomycetes and clade B Sebacinales, hitherto not described as ericoid mycorrhizal fungi.


Subject(s)
Ericaceae/classification , Ericaceae/microbiology , Mycorrhizae/isolation & purification , DNA Primers , DNA, Plant/genetics , Ericaceae/genetics , Ericaceae/ultrastructure , Europe , Geography , Microscopy, Electron , Mycorrhizae/classification , Mycorrhizae/genetics , Mycorrhizae/ultrastructure , Phylogeny , Plant Roots/microbiology , Plant Roots/ultrastructure , Polymerase Chain Reaction , South America , Species Specificity
9.
Mycol Res ; 110(Pt 11): 1257-70, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17081740

ABSTRACT

The mycorrhizal state of epiphytic orchids has been controversially discussed, and the state and mycobionts of the pleurothallid orchids, occurring abundantly and with a high number of species on stems of trees in the Andean cloud forest, were unknown. Root samples of 77 adult individuals of the epiphytic orchids Stelis hallii, S. superbiens, S. concinna and Pleurothallis lilijae were collected in a tropical mountain rainforest of southern Ecuador. Ultrastructural evidence of symbiotic interaction was combined with molecular sequencing of fungi directly from the mycorrhizas and isolation of mycobionts. Ultrastructural analyses displayed vital orchid mycorrhizas formed by fungi with an imperforate parenthesome and cell wall slime bodies typical for the genus Tulasnella. Three different Tulasnella isolates were obtained in pure culture. Phylogenetic analysis of nuclear rDNA sequences from coding regions of the ribosomal large subunit (nucLSU) and the 5.8S subunit, including parts of the internal transcribed spacers, obtained directly from the roots and from the fungal isolates, yielded seven distinct Tulasnella clades. Tulasnella mycobionts in Stelis concinna were restricted to two Tulasnella sequence types while the other orchids were associated with up to six Tulasnella sequence types. All Tulasnella sequences are new to science and distinct from known sequences of mycobionts of terrestrial orchids. The results indicate that tulasnelloid fungi, adapted to the conditions on tree stems, might be important for orchid growth and maintenance in the Andean cloud forest.


Subject(s)
Mycorrhizae/genetics , Orchidaceae/microbiology , Ecuador , Microscopy, Electron, Transmission , Molecular Sequence Data , Mycorrhizae/classification , Mycorrhizae/ultrastructure , Phylogeny , Plant Roots/microbiology , Plant Roots/ultrastructure , RNA, Ribosomal/genetics , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNA , Symbiosis
10.
New Phytol ; 169(2): 355-65, 2006.
Article in English | MEDLINE | ID: mdl-16411938

ABSTRACT

Cavendishia nobilis var. capitata is an endemic member of the Ericaceae growing as a hemiepiphyte in the tropical mountain rain forest of southern Ecuador. Mycorrhizas were collected from 20 individuals along an altitudinal gradient between 1850 and 2300 m. Transmission electron microscopy was used to study the symbiotic association in detail, and phylogenetic analyses based on nuclear rDNA coding for the ribosomal large subunit (nucLSU) were carried out to identify the associated mycorrhizal fungi. Microscopic and ultrastructural investigations showed the formation of a hyphal sheath, intercellular penetration of fine hyphae and colonization of the cortical cells by swollen hyphae of the same fungus. These structures were formed by hymenomycetes and ascomycetes. Molecular phylogenetic analysis detected seven groups of mycorrhizal fungi belonging to the Sebacinales. This is the first study to obtain evidence of ectendomycorrhizas in the Vaccinioideae. The ascomycetous nucLSU sequences belonged to members of the Leotiomycetes. The ectendomycorrhiza of C. nobilis with Sebacinales is discussed as a specific, hitherto undescribed mycorrhizal subcategory of ectomycorrhizas. We propose the term 'cavendishioid mycorrhiza'. This subcategory is most likely specific for the Andean clade of Ericaceae.


Subject(s)
Ecosystem , Ericaceae/microbiology , Mycorrhizae/classification , Mycorrhizae/isolation & purification , Rain , Tropical Climate , Ecuador , Genes, Fungal , Mycorrhizae/genetics , Mycorrhizae/ultrastructure , Phylogeny , Plant Roots/microbiology , Plant Roots/ultrastructure , Symbiosis
11.
New Phytol ; 165(3): 923-36, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15720703

ABSTRACT

* Three members of the Nyctaginaceae, two Neea species and one Guapira species, occurred scattered within a very species-rich neotropical mountain rain forest. The three species were found to form ectomycorrhizas of very distinctive characters, while all other tree species examined formed arbuscular mycorrhizas. * The ectomycorrhizas were structurally typified according to light and transmission electron microscope investigations. The internal transcribed spacer (ITS) rDNA and part of the nuclear large subunit (LSU, 28S) rDNA of the mycorrhiza forming fungi were amplified and sequenced. Phylogenetic analyses were carried out. * Neea species 1 was found to form typical ectomycorrhizas with five different fungal species, Russula puiggarii, Lactarius sp., two Tomentella or Thelephora species, and one ascomycete. Neea species 2 and the Guapira species were associated with only one fungus each, a Tomentella/Thelephora species clustering closely together in an ITS-neighbour-joining tree. The long and fine rootlets of the Guapira species showed proximally a hyphal mantle and a Hartig net, but distally intracellular fungal colonization of the epidermis and root hair development. The ectomycorrhizal segments of the long roots of Neea species 2 displayed a hyphal mantle and a Hartig net around alive root-hair-like outgrowths of the epidermal cells. * The distribution and the evolution of ectomycorrhizas in the predominantly neotropic Nyctaginaceae are discussed.


Subject(s)
Mycorrhizae/physiology , Nyctaginaceae/microbiology , Ascomycota/physiology , Basidiomycota/physiology , Ecuador , Phylogeny , Plant Roots/microbiology , Plant Roots/ultrastructure
12.
J Pediatr ; 144(1): 93-9, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14722525

ABSTRACT

OBJECTIVE: The autosomal-dominant form of the hyperimmunoglobulin E syndrome (AD-HIES) has been described as a multisystem disorder including immune, skeletal, and dental abnormalities. Variants of AD-HIES are known but not well defined. METHODS: We evaluated 13 human immunodeficiency virus-seronegative patients from six consanguineous families with an autosomal-recessive form of hyperimmunoglobulin E syndrome (AR-HIES) and 68 of their relatives. RESULTS: Persons affected with AR-HIES presented with the classical immunologic findings of hyperimmunoglobulin E syndrome, including recurrent staphylococcal infections of the skin and respiratory tract, eczema, elevated serum immunoglobulin E, and hypereosinophilia. In addition, severe recurrent fungal and viral infections with molluscum contagiosum, herpes zoster, and herpes simplex were noted. Autoimmunity was seen in two patients. Central nervous system sequelae, including hemiplegia, ischemic infarction, and subarachnoid hemorrhages, were common and contributed to high mortality. Notably, patients with AR-HIES did not have skeletal or dental abnormalities and did not develop pneumatoceles, as seen in AD-HIES. In lymphocyte proliferation assays, patients' cells responded poorly to mitogens and failed to proliferate in response to antigens, despite the presence of normal numbers of lymphocyte subpopulations. CONCLUSION: The autosomal-recessive form of hyperimmunoglobulin E syndrome is a primary immunodeficiency with elevated immunoglobulin E, eosinophilia, vasculitis, autoimmunity, central nervous system symptoms, and high mortality. AR-HIES lacks several of the key findings of AD-HIES and therefore represents a different, previously unrecognized disease entity.


Subject(s)
Job Syndrome/genetics , Autoimmunity , Child , Child, Preschool , Female , Humans , Infant , Job Syndrome/diagnosis , Job Syndrome/immunology , Male , Pedigree
13.
Mycol Res ; 107(Pt 10): 1143-56, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14635763

ABSTRACT

Thirty South American species of Cortinarius belonging to the subgenera Telamonia, Dermocybe, Myxacium, Phlegmacium, and Cystogenes were studied using an integrated approach that included morphological, anatomical, and ultrastructural data, and also molecular phylogenetic analysis of nuclear rDNA sequences. The micromorphology of the basidiomes was studied by light microscopy, and the principal structures were illustrated by line drawings. Basidiospore ornamentation was studied by scanning electron microscopy (SEM). Nuclear internal transcribed spacers (ITS, including the 5.8S gene) and the rDNA coding for the D1/D2 domains of the large ribosomal subunit (LSU) were sequenced and analysed using a Bayesian Markov chain Monte Carlo method to estimate phylogenetic relationships between the studied Cortinarius species. Morphology and anatomy of the pileus surface and basidiome pigmentation appeared to be the most useful characters to delimit some natural groups, whereas microcharacters related to the structure of pileus context, hymenophoral and stipe trama were of little taxonomic value. Basidiospore morphology and cheilocystidia seem to be taxonomically relevant at the species level. The following five infrageneric groups were supported by the morphological, chemical and molecular data: (1) Telamonia characterized by wide hyaline hyphae of the veil and by small basidiomes; (2) Dermocybe spp. with an epicutis as the most external layer of the pileus, and skyrin and hypericin pigments; (3) Dermocybe spp. with a thin viscid layer on the pileus, and endocrocin and dermolutein pigments; (4) Phlegmacium spp. characterized by a long and radicating stipe; and (5) Phlegmacium spp. that overlap in some macrocharacters with Telamonia species. Our analyses suggest that classification concepts based mainly on macromorphological characters are likely to lead to artificial grouping, whereas certain microscopical and chemical characters seem to be useful in constructing a more natural classification system for Cortinarius.


Subject(s)
Agaricales/cytology , Agaricales/genetics , Agaricales/classification , Base Sequence , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Evolution, Molecular , Microscopy, Electron, Scanning , Phylogeny , South America
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