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1.
Biodivers Data J ; 12: e120292, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38469225

RESUMEN

Background: Bioblitzes are a tool for the rapid appraisal of biodiversity and are particularly useful in remote and understudied regions and for understudied taxa. Lichens are an example of an often overlooked group, despite being widespread in virtually all terrestrial ecosystems and having many important ecological functions. New information: We report the lichens and allied fungi collected during the 2018 terrestrial bioblitz conducted on Calvert Island on the Central Coast of British Columbia, Canada. We identified 449 specimens belonging to 189 species in 85 genera, increasing the total number of species known from Calvert Island to 194, and generated Internal Transcribed Spacer (ITS) sequences for 215 specimens from 121 species. Bryoriafurcellata, Chaenothecopsislecanactidis and C.nigripunctata were collected for the first time in British Columbia. We also found Pseudocyphellariarainierensis, which is listed as Special Concern on the federal Species at Risk Act, and other rarely reported species in British Columbia including Opegraphasphaerophoricola, Protomicarealimosa, Raesaeneniahuuskonenii and Sareadifformis. We demonstrate that DNA barcoding improves the scope and accuracy of expert-led bioblitzes by facilitating the detection of cryptic species and allowing for consistent identification of chemically and morphologically overlapping taxa. Despite the spatial and temporal limitations of our study, the results highlight the value of intact forest ecosystems on the Central Coast of British Columbia for lichen biodiversity, education and conservation.

2.
Mycologia ; 115(2): 187-205, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36736327

RESUMEN

Variation in mitochondrial genome composition across intraspecific, interspecific, and higher taxonomic scales has been little studied in lichen obligate symbioses. Cladonia is one of the most diverse and ecologically important lichen genera, with over 500 species representing an array of unique morphologies and chemical profiles. Here, we assess mitochondrial genome diversity and variation in this flagship genus, with focused sampling of two clades of the "true" reindeer lichens, Cladonia subgenus Cladina, and additional genomes from nine outgroup taxa. We describe composition and architecture at the gene and the genome scale, examining patterns in organellar genome size in larger taxonomic groups in Ascomycota. Mitochondrial genomes of Cladonia, Pilophorus, and Stereocaulon were consistently larger than those of Lepraria and contained more introns, suggesting a selective pressure in asexual morphology in Lepraria driving it toward genomic simplification. Collectively, lichen mitochondrial genomes were larger than most other fungal life strategies, reaffirming the notion that coevolutionary streamlining does not correlate to genome size reductions. Genomes from Cladonia ravenelii and Stereocaulon pileatum exhibited ATP9 duplication, bearing paralogs that may still be functional. Homing endonuclease genes (HEGs), though scarce in Lepraria, were diverse and abundant in Cladonia, exhibiting variable evolutionary histories that were sometimes independent of the mitochondrial evolutionary history. Intraspecific HEG diversity was also high, with C. rangiferina especially bearing a range of HEGs with one unique to the species. This study reveals a rich history of events that have transformed mitochondrial genomes of Cladonia and related genera, allowing future study alongside a wealth of assembled genomes.


Asunto(s)
Genoma Mitocondrial , Líquenes , Líquenes/genética , Líquenes/microbiología , Sintenía , Evolución Biológica , Filogenia
3.
J Fungi (Basel) ; 8(5)2022 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-35628746

RESUMEN

Robust species delimitations provide a foundation for investigating speciation, phylogeography, and conservation. Here we attempted to elucidate species boundaries in the cosmopolitan lichen-forming fungal taxon Lecanora polytropa. This nominal taxon is morphologically variable, with distinct populations occurring on all seven continents. To delimit candidate species, we compiled ITS sequence data from populations worldwide. For a subset of the samples, we also generated alignments for 1209 single-copy nuclear genes and an alignment spanning most of the mitochondrial genome to assess concordance among the ITS, nuclear, and mitochondrial inferences. Species partitions were empirically delimited from the ITS alignment using ASAP and bPTP. We also inferred a phylogeny for the L. polytropa clade using a four-marker dataset. ASAP species delimitations revealed up to 103 species in the L. polytropa clade, with 75 corresponding to the nominal taxon L. polytropa. Inferences from phylogenomic alignments generally supported that these represent evolutionarily independent lineages or species. Less than 10% of the candidate species were comprised of specimens from multiple continents. High levels of candidate species were recovered at local scales but generally with limited overlap across regions. Lecanora polytropa likely ranks as one of the largest species complexes of lichen-forming fungi known to date.

5.
Investig Clin Urol ; 58(6): 447-452, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29124245

RESUMEN

Purpose: To report our outcomes with the use of a thermo-expandable metallic intraprostatic stent (Memokath) for patients with bladder outlet obstruction (BOO) secondary to prostatic obstruction, and to assess it is a feasible option for many frail and elderly men unsuitable for surgery. Materials and Methods: We reviewed patients who underwent insertion of a Memokath stent for BOO over 17 years (January 1999 to December 2015) at one regional center over a long follow-up period (median, 7 years). Patients were selected if they had obstructive urinary symptoms or urinary retention with an indwelling catheter in situ, and were ineligible for transurethral resection of the prostate (TURP) under general or spinal anesthesia. Primary outcomes assessed were the improvement in urinary symptoms and voiding parameters, as well as the ability to void spontaneously if catheterized, along with complications. Results: One hundred forty-four patients who presented with BOO or urinary retention had a Memokath stent inserted. Ninety patients (62.5%) had a successful stent insertion with a significant difference between the median preoperative (550 mL) and postoperative residual volume (80 mL, p<0.0001). Nearly two-thirds of men (64%) returned to unassisted voiding with no increased risk of complications over time. Fifty-four patients (37.5%) experienced stent failure. Main complications requiring stent removal or repositioning were migration, occlusion, refractory urinary retention and irritative voiding symptoms. Conclusions: In elderly and frail men with BOO deemed unsuitable to undergo TURP, prostatic stent is a safe and practical alternative to long-term catheterization.


Asunto(s)
Hiperplasia Prostática/complicaciones , Stents , Obstrucción del Cuello de la Vejiga Urinaria/terapia , Retención Urinaria/terapia , Anciano , Anciano de 80 o más Años , Remoción de Dispositivos , Fragilidad/complicaciones , Humanos , Masculino , Próstata , Diseño de Prótesis , Falla de Prótesis , Stents/efectos adversos , Obstrucción del Cuello de la Vejiga Urinaria/etiología , Retención Urinaria/etiología
6.
Environ Sci Pollut Res Int ; 22(12): 9323-31, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25598157

RESUMEN

Pollution control initiatives in Greater Sudbury, Ontario, Canada, resulted in the decommissioning of the Coniston Smelter in 1972. The last assessment of the effects from the smelter on the surrounding lichen biota was in 1990, which showed an overall improvement in richness following these initiatives, but still few species were present close to the smelter. We examined five sites along this gradient to determine if this pattern is still present on the landscape. Sixty-four macrolichen species in 15 genera were found. Lichen richness and Shannon diversity increased at all sites, but the increase was no longer linear with distance from the smelter. There was no significant difference between lichen richness and diversity at sites at increasing distances from the smelter. We show that past air pollution from the Coniston Smelter is no longer restricting lichen growth and development in the Greater Sudbury area as it was historically. Lichen populations are, therefore, now shaped by other environmental variables.


Asunto(s)
Cobre/toxicidad , Contaminantes Ambientales/toxicidad , Líquenes/efectos de los fármacos , Níquel/toxicidad , Canadá , Cobre/química , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/química , Líquenes/crecimiento & desarrollo , Metalurgia , Níquel/química , Factores de Tiempo
7.
Conserv Biol ; 27(5): 1020-30, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23869621

RESUMEN

Lichens are an important component of the boreal forest, where they are long lived, tend to accumulate in older stands, and are a major food source for the threatened woodland caribou (Rangifer tarandus caribou). To be fully sustainable, silvicultural practices in the boreal forest must include the conservation of ecological integrity. Dominant forest management practices, however, have short-term negative effects on lichen diversity, particularly the application of herbicides. To better understand the long-term effects of forest management, we examined lichen regeneration in 35 mixed black spruce (Picea mariana) and jack pine (Pinus banksiana) forest stands across northern Ontario to determine recovery following logging and postharvest silvicultural practices. Our forest stands were 25-40 years old and had undergone 3 common sivilcultural treatments that included harvested and planted; harvested, planted, and treated with N-[phosphonomethyl] glycine (glyphosate); and harvested, planted, and treated with 2,4-dichlorophenoxyacetic acid (2,4-D). Forest stands with herbicide treatments had lower lichen biomass and higher beta and gamma diversity than planted stands that were not treated chemically or control stands. In northwestern Ontario, planted stands that were not treated chemically had significantly greater (p < 0.05) alpha diversity than stands treated with herbicides or control stands. Our results show that common silvicultural practices do not emulate natural disturbances caused by wildfires in the boreal forest for the lichen community. We suggest a reduction in the amount of chemical application be considered in areas where lichen biomass is likely to be high and where the recovery of woodland caribou is an objective.


Asunto(s)
Conservación de los Recursos Naturales , Líquenes/fisiología , Árboles , Animales , Biodiversidad , Agricultura Forestal , Análisis Multivariante , Ontario , Dinámica Poblacional , Reno/fisiología
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