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1.
Bot Stud ; 64(1): 17, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410314

RESUMO

BACKGROUND: Globally, many undescribed fungal taxa reside in the hyperdiverse, yet undersampled, tropics. These species are under increasing threat from habitat destruction by expanding extractive industry, in addition to global climate change and other threats. Reserva Los Cedros is a primary cloud forest reserve of ~ 5256 ha, and is among the last unlogged watersheds on the western slope of the Ecuadorian Andes. No major fungal survey has been done there, presenting an opportunity to document fungi in primary forest in an underrepresented habitat and location. Above-ground surveys from 2008 to 2019 resulted in 1760 vouchered collections, cataloged and deposited at QCNE in Ecuador, mostly Agaricales sensu lato and Xylariales. We document diversity using a combination of ITS barcode sequencing and digital photography, and share the information via public repositories (GenBank & iNaturalist). RESULTS: Preliminary identifications indicate the presence of at least 727 unique fungal species within the Reserve, representing 4 phyla, 17 classes, 40 orders, 101 families, and 229 genera. Two taxa at Los Cedros have recently been recommended to the IUCN Fungal Red List Initiative (Thamnomyces chocöensis Læssøe and "Lactocollybia" aurantiaca Singer), and we add occurrence data for two others already under consideration (Hygrocybe aphylla Læssøe & Boertm. and Lamelloporus americanus Ryvarden). CONCLUSIONS: Plants and animals are known to exhibit exceptionally high diversity and endemism in the Chocó bioregion, as the fungi do as well. Our collections contribute to understanding this important driver of biodiversity in the Neotropics, as well as illustrating the importance and utility of such data to conservation efforts. RESUMEN: Antecedentes: A nivel mundial muchos taxones fúngicos no descritos residen en los trópicos hiper diversos aunque continúan submuestreados. Estas especies están cada vez más amenazadas por la destrucción del hábitat debido a la expansión de la industria extractivista además del cambio climático global y otras amenazas. Los Cedros es una reserva de bosque nublado primario de ~ 5256 ha y se encuentra entre las últimas cuencas hidrográficas no explotadas en la vertiente occidental de los Andes ecuatorianos. Nunca antes se ha realizado un estudio de diversidad micológica en el sitio, lo que significa una oportunidad para documentar hongos en el bosque primario, en hábitat y ubicación subrepresentatadas. El presente estudio recopila información entre el 2008 y 2019 muestreando material sobre todos los sustratos, reportando 1760 colecciones catalogadas y depositadas en el Fungario del QCNE de Ecuador, en su mayoría Agaricales sensu lato y Xylariales; además se documenta la diversidad mediante secuenciación de códigos de barras ITS y fotografía digital, la información está disponible en repositorios públicos digitales (GenBank e iNaturalist). RESULTADOS: La identificación preliminar indica la presencia de al menos 727 especies únicas de hongos dentro de la Reserva, que representan 4 filos, 17 clases, 40 órdenes, 101 familias y 229 géneros. Recientemente dos taxones en Los Cedros se recomendaron a la Iniciativa de Lista Roja de Hongos de la UICN (Thamnomyces chocöensis Læssøe y "Lactocollybia" aurantiaca Singer) y agregamos datos de presencia de otros dos que ya estaban bajo consideración (Hygrocybe aphylla Læssøe & Boertm. y Lamelloporus americanus Ryvarden). CONCLUSIONES: Se sabe que plantas y animales exhiben una diversidad y endemismo excepcionalmente altos en la bioregión del Chocó y los hongos no son la excepción. Nuestras colecciones contribuyen a comprender este importante promotor de la biodiversidad en el Neotrópico además de ilustrar la importancia y utilidad de dichos datos para los esfuerzos de conservación.

2.
Rev Sci Instrum ; 79(4): 043105, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18447521

RESUMO

This article presents a new type of low-energy crossed-beam electron spectrometer for measuring angular differential cross sections of electron-impact excitation of atomic and molecular targets. Designed for investigations at energies close to excitation thresholds, the spectrometer combines a pulsed electron beam with the time-of-flight technique to distinguish between scattering channels. A large-area, position-sensitive detector is used to offset the low average scattering rate resulting from the pulsing duty cycle, without sacrificing angular resolution. A total energy resolution better than 150 meV (full width at half maximum) at scattered energies of 0.5-3 eV is achieved by monochromating the electron beam prior to pulsing it. The results of a precision measurement of the differential cross section for electron-impact excitation of helium, at an energy of 22 eV, are used to assess the sensitivity and resolution of the spectrometer.

3.
Neurology ; 49(2): 568-72, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9270598

RESUMO

The clinical presentation of amyotrophic lateral sclerosis (ALS) is variable and overlaps with that of other motor neuron diseases such as spinobulbar muscular atrophy (SBMA; Kennedy disease). With the identification of disease-specific mutations such as the CAG repeat expansion in the androgen receptor in SBMA, an accurate molecular diagnosis can be made in some patients with motor neuron disease. To determine the extent of misdiagnosis of ALS we screened 147 male ALS patients and 100 unrelated male patients from 100 familial ALS (FALS) kindreds for the presence of the SBMA mutation using polymerase chain reaction methods. We show that ALS was clinically misdiagnosed in 2% of sporadic cases and in two of the 100 FALS kindreds. This study underscores the difficulty in distinguishing SBMA from ALS clinically, particularly in patients who lack the classic signs of each disease.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Testes Genéticos , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Caracteres Sexuais , Esclerose Lateral Amiotrófica/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Sequências Repetitivas de Ácido Nucleico
4.
J Neurol Sci ; 129 Suppl: 38-41, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7595616

RESUMO

We report 4 patients with amyotrophic lateral sclerosis (ALS) complaining of thoracic radicular symptoms. We postulate that in some patients paraspinal muscle weakness can result in an increased thoracic kyphosis, possibly producing traction on the thoracic roots.


Assuntos
Esclerose Lateral Amiotrófica/complicações , Cifose/etiologia , Radiculopatia/etiologia , Vértebras Torácicas/diagnóstico por imagem , Idoso , Esclerose Lateral Amiotrófica/diagnóstico por imagem , Feminino , Humanos , Cifose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiculopatia/diagnóstico por imagem , Ultrassonografia
6.
Neurology ; 71(22): 1770-5, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19029516

RESUMO

BACKGROUND: Previous human clinical trials of insulin-like growth factor type I (IGF-1) in amyotrophic lateral sclerosis (ALS) have been inconsistent. This phase III, randomized, double-blind, placebo-controlled study was undertaken to address whether IGF-1 benefited patients with ALS. METHODS: A total of 330 patients from 20 medical centers were randomized to receive 0.05 mg/kg body weight of human recombinant IGF-1 given subcutaneously twice daily or placebo for 2 years. The primary outcome measure was change in their manual muscle testing score. Secondary outcome measures included tracheostomy-free survival and rate of change in the revised ALS functional rating scale. Intention to treat analysis was used. RESULTS: There was no difference between treatment groups in the primary or secondary outcome measures after the 2-year treatment period. CONCLUSIONS: Insulin-like growth factor type I does not provide benefit for patients with amyotrophic lateral sclerosis.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/fisiopatologia , Fármacos do Sistema Nervoso Central/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Fármacos do Sistema Nervoso Central/efeitos adversos , Deglutição , Método Duplo-Cego , Feminino , Força da Mão , Humanos , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Tromboembolia/induzido quimicamente , Fatores de Tempo , Traqueostomia , Falha de Tratamento
7.
Headache ; 29(2): 82-5, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2708040

RESUMO

Two adults presented with new-onset migrainous-type visual disturbances and had angiographically demonstrated filling defects near the torcular Herophili. Neither patient had a visual field deficit nor cerebral computed tomography evidence of an occipital infarction. The association of migraine-like visual phenomena with cerebral venous thrombosis may provide insight into the pathogenesis of migraine.


Assuntos
Embolia e Trombose Intracraniana/complicações , Transtornos de Enxaqueca/etiologia , Transtornos da Visão/etiologia , Adulto , Feminino , Humanos , Embolia e Trombose Intracraniana/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia
8.
Stroke ; 19(4): 525-8, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3363582

RESUMO

We report a young migraine sufferer who developed bilateral posterior cerebral artery territory infarcts during the course of his classic migraines, the second of which was associated with intraluminal clot in the posterior cerebral artery. To our knowledge, bilateral posterior cerebral artery stroke from spontaneous migraine has not been reported. Head computed tomographic, magnetic resonance imaging, and angiographic correlation is presented. The mechanism of migrainous infarction may be in part explained by caliber changes in arterioles and capillaries leading to flow reduction in the more proximal conduit arteries combined with the associated coagulopathy that has been previously documented during migraine attacks.


Assuntos
Transtornos Cerebrovasculares/etiologia , Transtornos de Enxaqueca/complicações , Adulto , Angiografia Cerebral , Artérias Cerebrais , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/etiologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/diagnóstico por imagem , Humanos , Embolia e Trombose Intracraniana/diagnóstico por imagem , Embolia e Trombose Intracraniana/etiologia , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
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