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1.
J Fungi (Basel) ; 9(9)2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37755012

RESUMEN

Armillaria altimontana is a fungus (Basidiomycota, Agaricomycetes, Agaricales, and Physalacriaceae) that is generally considered as a weak/opportunistic pathogen or saprophyte on many tree hosts. It widely occurs across the northwestern USA to southern British Columbia, Canada, but relatively little is known about its ecological role in the diverse forest ecosystems where it occurs. This review summarizes the biology and ecology of A. altimontana, including its identification, life cycle, distribution, host associations, and bioclimatic models under climate change.

2.
Microb Ecol ; 85(2): 708-729, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35312808

RESUMEN

Armillaria species show considerable variation in ecological roles and virulence, from mycorrhizae and saprophytes to important root pathogens of trees and horticultural crops. We studied two Armillaria species that can be found in coniferous forests of northwestern USA and southwestern Canada. Armillaria altimontana not only is considered as a weak, opportunistic pathogen of coniferous trees, but it also appears to exhibit in situ biological control against A. solidipes, formerly North American A. ostoyae, which is considered a virulent pathogen of coniferous trees. Here, we describe their genome assemblies and present a functional annotation of the predicted genes and proteins for the two Armillaria species that exhibit contrasting ecological roles. In addition, the soil microbial communities were examined in association with the two Armillaria species within a 45-year-old plantation of western white pine (Pinus monticola) in northern Idaho, USA, where A. altimontana was associated with improved tree growth and survival, while A. solidipes was associated with reduced growth and survival. The results from this study reveal a high similarity between the genomes of the beneficial/non-pathogenic A. altimontana and pathogenic A. solidipes; however, many relatively small differences in gene content were identified that could contribute to differences in ecological lifestyles and interactions with woody hosts and soil microbial communities.


Asunto(s)
Armillaria , Pinus , Tracheophyta , Armillaria/genética , Suelo , Árboles , Bosques , Genómica
3.
Plant Dis ; 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33174801

RESUMEN

Armillaria root and butt diseases, which are a global issue, can be influenced by changing environmental conditions. Armillaria gallica is a well-known pathogen of diverse trees worldwide (Brazee and Wick 2009). Besides A. gallica causing root rot of Hemerocallis sp. and Cornus sp. in South Carolina (Schnabel et al. 2005), little is reported on the distribution and host range of A. gallica in the southeastern USA. In July 2017, three Armillaria isolates were obtained from two naturally occurring hosts in Georgia, USA and cultured on malt extract medium (3% malt extract, 3% dextrose, 1% peptone, and 1.5% agar). One isolate (GA3) was obtained in Unicoi State Park near Helen, Georgia (Lat. 34.712275, Long. -83.727765, elev. 498 m) from the basal portion of Rhododendron sp. with extensive root/butt decay, but no crown symptoms were evident (Supplementary Figure 1). GA4 and GA5 (Lat. 33.902433, Long. -83.382453, elev. 215 m) were isolated from wind-felled Quercus rubra (red oak) with root disease at the State Botanical Gardens in Athens, Georgia. GA4 was associated with a large root ball (ca. 4-m diameter) (Supplementary Figure 2), and GA5 was obtained from a mature tree with infected roots, with characteristic spongy rot of Armillaria root disease. Crown symptoms could not be evaluated because the crowns had been removed before the collections. Several other oaks with Armillaria root disease were noted throughout the State Botanical Gardens. Pairing tests reduced these three isolates (whiteish mycelia with a dark, brownish crust and rhizomorphs), to two genets with GA4 = GA5. Both genets (GA3 and GA4) were identified as A. gallica using translation elongation factor 1α (tef1) sequences (Genbank Nos. MT761697 and MT761698, respectively) that showed ≥ 97% identity (≥ 98% coverage) with A. gallica sequences (KF156772, KF156775). Also, nine replications of somatic pairing tests showed 33 - 67% compatibility with A. gallica (occurs in southeastern USA), compared with 0 - 22% for A. mexicana, A. mellea (occurs in southeastern USA), A. solidipes, and Desarmillaria tabescens (occurs in southeastern USA). To our knowledge, this note represents the first report of A. gallica on Rhododendron and Q. rubra in Georgia, USA, which has experienced severe drought in recent decades (e.g., Park Williams et al. 2017) that could predispose trees to Armillaria infection (e.g., Wargo 1996). Quercus rubra was previously reported as a host of A. gallica in Arkansas (Kelley et al. 2009) and Massachusetts (Brazee and Wick 2009), USA. In Missouri, USA, A. gallica has been reported as a weak pathogen with potential biological control against A. mellea (Bruhn et al. 2000). Other reports from several regions on various hosts suggest pathogenicity of A. gallica is associated with changing climate (Nelson et al. 2013, Kim et al. 2017, Kubiak et al. 2017). Wide genetic variation and/or cryptic speciation within A. gallica may account for differences in ecological behavior (Klopfenstein et al. 2017), but this is difficult to evaluate because Armillaria pathogenicity tests cannot be used on most forest tree seedlings. This study suggests that A. gallica is more widespread than previously known and its adverse impacts on woody plants may intensify over time, depending on the environmental conditions. Further studies are needed to determine environmental influences on A. gallica, the full distribution of A. gallica, and its effects in forests of the southeastern USA.

4.
Plant Dis ; 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32720881

RESUMEN

In July-August 2019, seven Armillaria isolates (derived from rhizomorphs and mycelial fans of infected roots) were collected in association with woody hosts in the central Mexico: states of Guanajuato (MEX204), Jalisco (MEX206, MEX208, MEX209), and Michoacan (MEX211, MEX214, MEX216). All seven isolates were identified as Armillaria gallica based on translation elongation factor 1α (tef1) gene sequences (GenBank accession Nos.: MN839636 - MN839642 for MEX204, MEX206, MEX208, MEX209, MEX211, MEX214, and MEX216) and somatic pairing tests against known tester isolates. GenBank nucleotide BLAST results showed tef1 similarity for all isolates was highest for with A. gallica (≥ 97%; GenBank Accession Nos. KF156775 and KF156772). In replicated pairings against three tester isolates each for A. gallica, A. mellea, and A. mexicana, all isolates showed the highest compatibility with A. gallica (67-100%), with lower compatibility against A. mellea and A. mexicana, with 3-11% and 2-11%, respectively. Variations in compatibility among different tester isolates could reflect cryptic speciation within A. gallica (Klopfenstein et al., 2017). In Tarimoro, Guanajuato, MEX204 was isolated from infected Quercus jonesii (20°13'46.2"N 100°42'51.1"W, elevation 2286 m) that displayed root disease symptoms/signs (wilting/defoliation and mycelial fans within the roots). In a forested area of Mazamitla, Jalisco, MEX206 was isolated from infected Quercus laevis (19°54´52"N 103°00´07"W, elevation 2564 m) with root disease symptoms/signs (e.g., wilting, foliar chlorosis, and mycelial fans within the root crown); MEX208 was isolated from infected Pinus pseudostrobus (19°54´53"N 102°59´54"W, elevation 2554 m) with basal resinosis and mycelial fans; and MEX209 was collected from a symptomless P. devoniana (19°54'13.1"N 103°00'14.1"W, elevation 2566 m). In Zinapecuaro, Michoacan, MEX211 (19°53'28.8"N 100°39'44.0"W, elevation 2587 m) was isolated from infected Malus domestica with root disease that resulted in mortality; in Hidalgo, Michoacan, MEX214 (19°46'49"N 100°39'25.2"W, elevation 2961 m) and MEX216 (19°46'58"N 100°39'24"W, elevation 2958 m) were isolated from infected P. devoniana and P. teocote, respectively, which both displayed root disease symptoms/signs (basal resinosis and mycelial fans). Previously, A. gallica was reported in the State of Mexico, Veracruz, Oaxaca, Mexico (Elías-Román et al. 2013; Klopfenstein et al. 2014), but this represents the first report of A. gallica in Guanajuato, Jalisco, and Michoacan, Mexico. In contrast to other regions of North America (e.g., Bruhns et al. 2000), A. gallica was demonstrated to be a virulent pathogen on peach (Prunus persica) in central Mexico (Elías-Román et al. 2013). Unfortunately, tree seedlings cannot be used for Armillaria pathogenicity tests in a greenhouse or nursery; however, all root-diseased trees in this report showed Armillaria mycelial fans under the bark of a living tree, which are reliable indicators of pathogenicity, and no other root diseases were found. This report demonstrates that A. gallica is distributed across central Mexico, where it is associated with disease on Quercus, Pinus, and Malus. Such information is critical to increase our understanding of Armillaria root disease across diverse geographic regions and climates.

5.
Mycologia ; 110(2): 347-360, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29608410

RESUMEN

Armillaria mexicana (Agaricales, Physalacriaceae) is described as a new species based on morphology, DNA sequence data, and phylogenetic analyses. It clearly differs from previously reported Armillaria species in North, Central, and South America. It is characterized by the absence of fibulae in the basidioma, abundant cheilocystidia, and ellipsoidal, hyaline basidiospores that are apparently smooth under light microscope, but slightly to moderately rugulose under scanning electron microscope. It is differentiated from other Armillaria species by macromorphological characters, including annulus structure, pileus and stipe coloration, and other structures. DNA sequence data (nuc rDNA internal transcribed spacers [ITS1-5.8S-ITS2 = ITS], 28S D-domain, 3' end of 28S intergenic spacer 1, and translation elongation factor 1-α [TEF1]) show that A. mexicana sequences are quite distinct from sequences of analogous Armillaria species in GenBank. In addition, sequences of ITS of the A. mexicana ex-type culture reveal an ITS1 of 1299 bp and an ITS2 of 582 bp, the longest ITS regions reported thus far in fungi. Phylogenetic analysis based on TEF1 sequences place A. mexicana in a well-separated, monophyletic clade basal to the polyphyletic A. mellea complex.


Asunto(s)
Armillaria/clasificación , Armillaria/aislamiento & purificación , Armillaria/citología , Armillaria/genética , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , México , Microscopía , Microscopía Electrónica de Rastreo , Factor 1 de Elongación Peptídica/genética , Filogenia , ARN Ribosómico 28S/genética , Análisis de Secuencia de ADN
6.
Mycologia ; 109(1): 75-91, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28402796

RESUMEN

Armillaria possesses several intriguing characteristics that have inspired wide interest in understanding phylogenetic relationships within and among species of this genus. Nuclear ribosomal DNA sequence-based analyses of Armillaria provide only limited information for phylogenetic studies among widely divergent taxa. More recent studies have shown that translation elongation factor 1-α (tef1) sequences are highly informative for phylogenetic analysis of Armillaria species within diverse global regions. This study used Neighbor-net and coalescence-based Bayesian analyses to examine phylogenetic relationships of newly determined and existing tef1 sequences derived from diverse Armillaria species from across the Northern Hemisphere, with Southern Hemisphere Armillaria species included for reference. Based on the Bayesian analysis of tef1 sequences, Armillaria species from the Northern Hemisphere are generally contained within the following four superclades, which are named according to the specific epithet of the most frequently cited species within the superclade: (i) Socialis/Tabescens (exannulate) superclade including Eurasian A. ectypa, North American A. socialis (A. tabescens), and Eurasian A. socialis (A. tabescens) clades; (ii) Mellea superclade including undescribed annulate North American Armillaria sp. (Mexico) and four separate clades of A. mellea (Europe and Iran, eastern Asia, and two groups from North America); (iii) Gallica superclade including Armillaria Nag E (Japan), multiple clades of A. gallica (Asia and Europe), A. calvescens (eastern North America), A. cepistipes (North America), A. altimontana (western USA), A. nabsnona (North America and Japan), and at least two A. gallica clades (North America); and (iv) Solidipes/Ostoyae superclade including two A. solidipes/ostoyae clades (North America), A. gemina (eastern USA), A. solidipes/ostoyae (Eurasia), A. cepistipes (Europe and Japan), A. sinapina (North America and Japan), and A. borealis (Eurasia) clade 2. Of note is that A. borealis (Eurasia) clade 1 appears basal to the Solidipes/Ostoyae and Gallica superclades. The Neighbor-net analysis showed similar phylogenetic relationships. This study further demonstrates the utility of tef1 for global phylogenetic studies of Armillaria species and provides critical insights into multiple taxonomic issues that warrant further study.


Asunto(s)
Armillaria/clasificación , Armillaria/genética , Factor 1 de Elongación Peptídica/genética , Filogenia , Asia , Europa (Continente) , América del Norte , Análisis de Secuencia de ADN
7.
Curr Med Res Opin ; 32(7): 1225-32, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26973059

RESUMEN

OBJECTIVES: The gene expression classifier (GEC, Afirma ) reclassifies as molecularly benign approximately one half of thyroid nodule fine-needle aspiration (FNA) biopsies with an initial indeterminate cytopathology diagnosis, facilitating clinical monitoring in lieu of diagnostic thyroid surgery. This study evaluated the long-term management patterns and thyroid surgery rates of GEC benign patients compared to a control group of cytopathology benign patients and also described the costs of thyroid surgery. METHODS: This retrospective cohort study used laboratory test results linked to payer medical claims data. Patients who underwent FNA biopsy between 1 January 2011 and 31 July 2013 were selected. GEC benign patients were matched 1:3 to cytopathology benign patients on biopsy year, gender, nodule size and age. Outcomes measured included thyroid-related follow-up clinic visits, ultrasound examinations and surgeries. RESULTS: Out of 2059 patients, matched groups consisting of 201 GEC benign patients and 603 cytopathology benign patients were evaluated over an average follow-up of 20 months. The proportions of GEC benign and cytopathology benign patients that underwent thyroid surgery (11.4% versus 10.1%, p = 0.594), and received a follow-up ultrasound exam (60.2% versus 61.7%, p = 0.706), respectively, were not significantly different. Average thyroid-related medical cost for the surgical episode and during 6 months following surgery were $10,432.00 (SD $8301) and $10,939.00 (SD $9656) respectively. LIMITATIONS: The study cohort included only patients whose diagnostic laboratory test results and administrative claims data were uniquely identifiable and could be linked on multiple identifiers; the rigorous matching and patient selection algorithms utilized improved the robustness and internal validity of the study. Claims were used as a proxy for clinical utilization without chart review confirmation. CONCLUSION: Patients with GEC and cytopathology benign diagnoses were managed similarly. The majority of patients in both groups did not undergo surgery and were managed with usual care, consisting of clinical follow-up and ultrasound exams.


Asunto(s)
Nódulo Tiroideo/genética , Nódulo Tiroideo/terapia , Adulto , Biopsia con Aguja Fina , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/patología
8.
J Multidiscip Healthc ; 8: 255-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26060404

RESUMEN

BACKGROUND AND AIMS: Few studies evaluate the impact of anesthesia providers during procedures, such as colonoscopy, on low-risk patients. The objective of this study was to compare the effect of anesthesia providers on several outcome variables, including major morbidity, following screening colonoscopies. METHODS: A propensity-matched cohort study of 14,006 patients who enrolled with a national insurer offering health maintenance organization (HMO), preferred provider organization (PPO), and Medicare Advantage plans for a screening colonoscopy between July 1, 2005 and June 30, 2007 were studied. Records were evaluated for completion of the colonoscopy, new cancer diagnosis (colon, anal, rectal) within 6 months of the colonoscopy, new primary diagnosis of myocardial infarction (MI), new primary diagnosis of stroke, hospital admission within 7 days of the colonoscopy, and adherence to guidelines for use of anesthesia providers. RESULTS: The presence of an anesthesia provider did not affect major morbidity or the percent of completed exams. Overall morbidity within 7 days was very low. When an anesthesia provider was present, a nonsignificant trend toward greater cancer detection within 6 months of the procedure was observed. Adherence to national guidelines regarding the use of anesthesia providers for low-risk patients was poor. CONCLUSION: A difference in outcome associated with the presence or absence of an anesthesia provider during screening colonoscopy in terms of MI, stroke, or hospital admission within 7 days of the procedure was not observed. Adherence to published guidelines for the use of anesthesia providers is low. The incidence of completed exams was unaffected by the presence of an anesthesia provider. However, a nonstatistically significant trend toward increased cancer detection requires further study.

10.
Surgery ; 154(6): 1420-6; discussion 1426-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24094448

RESUMEN

BACKGROUND: To provide population-based estimates of trends in thyroid nodule fine-needle aspirations (FNA) and operative volumes, we used multiple claims databases to quantify rates of these procedures and their association with the increasing incidence of thyroid cancer in the United States. METHOD: Private and public insurance claims databases were used to estimate procedure volumes from 2006 to 2011. Rates of FNA and thyroid operations related to thyroid nodules were defined by CPT4 codes associated with International Classification of Diseases, Ninth Revision Clinical Modification codes for nontoxic uni- or multinodular goiter and thyroid neoplasms. RESULTS: Use of thyroid FNA more than doubled during the 5-year study period (16% annual growth). The number of thyroid operations performed for thyroid nodules increased by 31%. Total thyroidectomies increased by 12% per year, whereas lobectomies increased only 1% per year. In 2011, total thyroidectomies accounted for more than half (56%) of the operations for thyroid neoplasms in the United States. Thyroid operations became increasingly (62%) outpatient procedures. CONCLUSION: Thyroid FNA and operative procedures have increased rapidly in the United States, with an associated increase in the incidence of thyroid cancer. The more substantial increase in number of total versus partial thyroid resections suggests that patients undergoing thyroid operation are perceived to have a greater risk of cancer as determined by preoperative assessments, but this trend could also increase detection of incidental microcarcinomas.


Asunto(s)
Biopsia con Aguja Fina/tendencias , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/cirugía , Biopsia con Aguja Fina/estadística & datos numéricos , Bases de Datos Factuales , Humanos , Incidencia , Neoplasias de la Tiroides/epidemiología , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/epidemiología , Nódulo Tiroideo/cirugía , Tiroidectomía/estadística & datos numéricos , Tiroidectomía/tendencias , Estados Unidos/epidemiología
12.
Neurosurgery ; 70(1): 211-9; discussion 219, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21768918

RESUMEN

This second part of a comprehensive review of primary vertebral tumors focuses on locally aggressive and malignant tumors. As discussed in the earlier part of the review, both benign and malignant types of these tumors affect the adult and the pediatric population, and an understanding of their subtleties may increase their effective resection. In this review, we discuss the epidemiologic, histological, and imaging features of the most common locally aggressive primary vertebral tumors (chordoma and giant-cell tumor) and malignant tumors (chondrosarcoma, Ewing sarcoma, multiple myeloma or plasmacytoma, and osteosarcoma). The figures used for illustration are from operative patients of the senior authors (Z.L.G. and J.H.C.). Taken together, parts 1 and 2 of this article provide a thorough and illustrative review of primary vertebral tumors.


Asunto(s)
Diagnóstico por Imagen , Neoplasias de la Columna Vertebral , Cordoma , Tumores de Células Gigantes , Humanos , Sarcoma de Ewing , Neoplasias de la Columna Vertebral/diagnóstico , Neoplasias de la Columna Vertebral/epidemiología , Neoplasias de la Columna Vertebral/cirugía
13.
Am J Manag Care ; 17(11): 753-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22084895

RESUMEN

OBJECTIVES: To describe persistence with teriparatide and other biologic therapies in Medicare Part D plans with and without a coverage gap. STUDY DESIGN: Retrospective (2006) cohort study of Medicare Part D prescription drug plan beneficiaries from a large benefits company. Two plans with a coverage gap (defined as "basic") were combined and compared with a single plan with coverage for generic and branded medications (defined as "complete"). METHODS: Patients taking alendronate (nonbiologic comparator), teriparatide, etanercept, adalimumab, interferon ß-1a, or glatiramer acetate were selected for the study. For patients with complete coverage, equivalent financial thresholds were used to define the "gap."The definition of discontinuation was failure to fill the index prescription after reaching the gap. RESULTS: For alendronate, 27% of 133,260 patients had enrolled in the complete plan. Patients taking biologic therapies had more commonly enrolled in complete plans: teriparatide (66% of 6221), etanercept (58% of 1469), adalimumab (52% of 824), interferon ß-1a (60% of 438), and glatiramer acetate (53% of 393). For patients taking either alendronate or teriparatide, discontinuation rates were higher in the basic, versus complete, plan (adjusted odds ratios, 2.02 and 3.56, respectively). Discontinuation did not significantly vary by plan type for etanercept, adalimumab, interferon ß-1a, or glatiramer acetate. CONCLUSIONS: For patients who reached the coverage gap, discontinuation was more likely for patients taking osteoporosis (OP) medication. Not having a coverage gap was associated with improved persistence with OP treatment.


Asunto(s)
Terapia Biológica/estadística & datos numéricos , Política de Salud , Cobertura del Seguro/estadística & datos numéricos , Pacientes no Asegurados/estadística & datos numéricos , Medicare Part D/estadística & datos numéricos , Adalimumab , Anciano , Alendronato/economía , Alendronato/uso terapéutico , Anticuerpos Monoclonales Humanizados/economía , Anticuerpos Monoclonales Humanizados/uso terapéutico , Terapia Biológica/economía , Terapia Biológica/métodos , Etanercept , Femenino , Acetato de Glatiramer , Accesibilidad a los Servicios de Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Inmunoglobulina G/economía , Inmunoglobulina G/uso terapéutico , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Péptidos/economía , Péptidos/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Estudios Retrospectivos , Teriparatido/economía , Teriparatido/uso terapéutico , Factores de Tiempo , Estados Unidos
14.
Neurosurgery ; 69(6): 1171-80, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21725252

RESUMEN

Primary vertebral tumors, although less common than metastases to the spine, make up a heterogeneous group of neoplasms that can pose diagnostic and treatment challenges. They affect both the adult and the pediatric population and may be benign, locally aggressive, or malignant. An understanding of typical imaging findings will aid in accurate diagnosis and help neurosurgeons appreciate anatomic subtleties that may increase their effective resection. An understanding of the histological similarities and differences between these tumors is imperative for all members of the clinical team caring for these patients. In this first review of 2 parts, we discuss the epidemiological, histological, and imaging features of the most common benign primary vertebral tumors-aneurysmal bone cyst, chondroma and enchondroma, hemangioma, osteoid osteoma, and osteoblastoma-and lesions related to eosinophilic granuloma and fibrous dysplasia. In addition, we discuss the basic management paradigms for each of these diagnoses. In combination with part II of the review, which focuses on locally aggressive and malignant tumors, this article provides a comprehensive review of primary vertebral tumors.


Asunto(s)
Neoplasias Óseas/patología , Diagnóstico por Imagen/métodos , Neoplasias de la Columna Vertebral/patología , Neoplasias Óseas/epidemiología , Humanos , Neoplasias de la Columna Vertebral/epidemiología
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