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1.
Environ Manage ; 74(1): 4-12, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38856731

RESUMO

Landscapes are conceptually fuzzy and rich, and subject to plural framings. They are places of inquiry and intervention for scientists and practitioners, but also concepts bound to peoples' dynamic identities, knowledge systems, inspiration, and well-being. These varying interpretations change the way landscapes function and evolve. Developed in the 1930s, Q-methodology is increasingly recognized for being useful in documenting and interrogating environmental discourses. Yet its application in the context of how integrated landscape approaches better navigate land-use dilemmas is still in its infancy. Based on our experience and emerging literature, such as the papers in this special collection, this article discusses the value of Q-methodology in addressing landscape sustainability issues. Q-methodology helps unravel and communicate common and contradicting landscape imaginaries and narratives in translational and boundary-spanning ways, thus bridging actors' different understandings of problems and solutions and revealing common or differentiated entry points for negotiating trade-offs between competing land uses. The methodology can be empowering for marginalized people by uncovering their views and aspirational values to decision-makers and policymakers. We argue that this potential can be further strengthened by using Q to identify counter-hegemonic discourses and alliances that combat injustices regarding whose knowledge and visions count. In this way, applying Q-methodology in integrated landscape approaches can become a key tool for transitioning toward just, inclusive, and sustainable landscapes.


Assuntos
Conservação dos Recursos Naturais , Negociação , Conservação dos Recursos Naturais/métodos , Humanos , Tomada de Decisões , Empoderamento
2.
Mov Disord ; 38(1): 82-91, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36258659

RESUMO

BACKGROUND: Isolated rapid-eye-movement sleep behavior disorder (iRBD) is in most cases a prodrome of neurodegenerative synucleinopathies, affecting 1% to 2% of middle-aged and older adults; however, accurate ambulatory diagnostic methods are not available. Questionnaires lack specificity in nonclinical populations. Wrist actigraphy can detect characteristic features in individuals with RBD; however, high-frequency actigraphy has been rarely used. OBJECTIVE: The aim was to develop a machine learning classifier using high-frequency (1-second resolution) actigraphy and a short patient survey for detecting iRBD with high accuracy and precision. METHODS: The method involved analysis of home actigraphy data (for seven nights and more) and a nine-item questionnaire (RBD Innsbruck inventory and three synucleinopathy prodromes of subjective hyposmia, constipation, and orthostatic dizziness) in a data set comprising 42 patients with iRBD, 21 sleep clinic patients with other sleep disorders, and 21 community controls. RESULTS: The actigraphy classifier achieved 95.2% (95% confidence interval [CI]: 88.3-98.7) sensitivity and 90.9% (95% CI: 82.1-95.8) precision. The questionnaire classifier achieved 90.6% accuracy and 92.7% precision, exceeding the performance of the Innsbruck RBD Inventory and prodromal questionnaire alone. Concordant predictions between actigraphy and questionnaire reached a specificity and precision of 100% (95% CI: 95.7-100.0) with 88.1% sensitivity (95% CI: 79.2-94.1) and outperformed any combination of actigraphy and a single question on RBD or prodromal symptoms. CONCLUSIONS: Actigraphy detected iRBD with high accuracy in a mixed clinical and community cohort. This cost-effective fully remote procedure can be used to diagnose iRBD in specialty outpatient settings and has potential for large-scale screening of iRBD in the general population. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Transtorno do Comportamento do Sono REM , Sinucleinopatias , Pessoa de Meia-Idade , Humanos , Idoso , Actigrafia/métodos , Transtorno do Comportamento do Sono REM/diagnóstico , Inquéritos e Questionários , Sono
3.
Wilderness Environ Med ; 33(3): 340-343, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35691768

RESUMO

Allium tricoccum (commonly known as "ramps") is an edible plant known for its strong garlic-like odor and onion flavor. Unfortunately, A tricoccum mimics such as Lily of the Valley (Convallaria majalis) and False Hellebore (Veratrum viride) can lead to foraging errors and subsequent patient harm/toxicity. We describe 3 adults who foraged and ate what they believed were A tricoccum and then subsequently became symptomatic with detectable digoxin concentrations. A 41-y-old woman, 41-y-old man, and a 31-y-old man presented to the emergency department after ingesting an unknown plant that was believed to be A tricoccum. On arrival to the emergency department, the patients were hypotensive and bradycardic. They had detectable digoxin concentrations ranging from 0.08 ng·mL-1 to 0.13 ng·mL-1. One patient received 20 vials of digoxin antibody fragments. All 3 patients recovered without complication. Laboratory analysis of plant specimen was positive for cyclopamine, a teratogenic alkaloid found in Veratrum californicum. A tricoccum foraging errors can be a source of morbidity given their similarity in appearance to plants like C majalis and V viride. C majalis causes a detectable digoxin concentration via its cardiac steroid compound (convallatoxin) that is similar to digoxin. V viride contains alkaloid compounds (such as veratridine) that can cross react with digoxin assays and lead to a falsely elevated digoxin concentration. Clinicians should be prompted to think about ingestion of C majalis or Veratrum spp. when patients present with bradycardia, gastrointestinal symptoms, and detectable digoxin concentrations after plant ingestion and/or foraging for A tricoccum.


Assuntos
Gastroenteropatias , Veratrum , Adulto , Digoxina , Feminino , Humanos , Fragmentos de Imunoglobulinas , Masculino , Veratridina
4.
Environ Manage ; 66(1): 72-90, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32333037

RESUMO

Tropical forest landscapes are undergoing rapid transition. Rural development aspirations are rising, and land use change is contributing to deforestation, degradation, and biodiversity loss, which threaten the future of tropical forests. Conservation initiatives must deal with complex social, political, and ecological decisions involving trade-offs between the extent of protected areas and quality of conservation. In Cambodia, smallholders and industrial economic land concessions drive deforestation and forest degradation. Rural economic benefits have not kept pace with development aspirations and smallholders are gradually expanding agriculture into protected forests. We examine the drivers and effects of rural forest landscape transitions in Cambodia to identify trade-offs between conservation and development. Using historical trends analysis and information gathered through key informant interviews, we describe how local communities perceive social and ecological changes, and examine the implications of local development aspirations for conservation. We explore three scenarios for the future of conservation in Cambodia, each with different conservation and community development outcomes. We contend that conservation efforts should focus on strengthening governance to meet social and environmental requirements for sustainable forest landscapes. We suggest potential entry points for governance improvements, including working with local decision-makers and fostering collaboration between stakeholders. There is a need for realistic priority setting in contested tropical forest landscapes. Prosperous rural economies are a necessary but not sufficient condition for conservation.


Assuntos
Conservação dos Recursos Naturais , Florestas , Agricultura , Biodiversidade , Camboja
6.
J Anal Toxicol ; 48(4): 210-216, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38581653

RESUMO

Monofluoroacetate is a highly lethal toxin that causes death by inhibiting cellular adenosine triphosphate (ATP) production. The heart and brain are the primary target organs. Acute death is attributed to cardiac fibrillation and/or convulsions. Although it occurs naturally in some plants, a major source of animal intoxication is access to sodium monofluoroacetate (NaMFA) pesticide, which continues to be a concern in the USA and around the world despite restricted use in some countries including the USA. There are also concerns about misuse of this pesticide for malicious poisoning. Currently, a tissue-based diagnostic method for NaMFA intoxication in animals is lacking. There is a critical need by the veterinary diagnostic community for a simple, sensitive and reliable tissue-based diagnostic test to confirm NaMFA poisoning in animals. We have developed and extensively evaluated a sensitive novel liquid chromatography combined with tandem mass spectrometry method suitable for this purpose. The limits of detection and limits of quantitation are 1.7 and 5.0 ng/g, respectively. The accuracy and precision met or exceeded expectations. The method performance was verified using the incurred kidney obtained from animal diagnostic cases. This novel kidney-based method is now available for clinical use and can help with diagnostic purposes, including detecting potential issues related to animal foods.


Assuntos
Fluoracetatos , Rim , Espectrometria de Massas em Tandem , Fluoracetatos/intoxicação , Animais , Rim/metabolismo , Cromatografia Líquida , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massa com Cromatografia Líquida
7.
J Vet Diagn Invest ; 36(1): 95-102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38018662

RESUMO

Astylus atromaculatus is a pollen beetle native to South America, commonly found in crop flowers. Experimental intoxication of sheep and guinea pigs by this beetle resulting in fibrinonecrotizing enteritis has been reported. We describe here 6 natural outbreaks of intoxication in cattle associated with consumption of alfalfa (5 of 6) and mixed native (1 of 6) pastures heavily contaminated with A. atromaculatus. The outbreaks occurred during the summer (January-February) of 2023 in Argentina (n = 4) and Uruguay (n = 2), in beef cattle under extensive or semi-extensive rearing systems, with overall cumulative incidence and mortality of 22.3% and 17.8%, respectively. The main clinical signs included acute onset of anorexia, lethargy, hyperthermia, hindlimb weakness, reluctance to move, and diarrhea, for up to 15 d. In 2 outbreaks, sudden death was observed. Eight Hereford, Angus, and/or crossbreed heifers, cows, steers, and/or calves were autopsied. Gross and microscopic findings included multifocal necrosis with fibrinous pseudomembranes in the forestomachs and/or small and large intestines. Fragments or whole specimens of A. atromaculatus were identified in the ruminal content of all animals. Testing for multiple gastroenteric pathogens was negative as was testing of A. atromaculatus for cantharidin and batrachotoxin. GC-MS and LC-MS/MS performed on the beetles did not identify any known toxic compounds. Based on the exposure to A. atromaculatus-contaminated pasture, gross and microscopic lesions, and negative results of all testing for multiple gastroenteric pathogens, a diagnosis of intoxication by A. atromaculatus is proposed. Disease caused by A. atromaculatus consumption has not been reported previously in cattle, to our knowledge.


Assuntos
Doenças dos Bovinos , Besouros , Doenças dos Ovinos , Animais , Bovinos , Feminino , Ovinos , Cobaias , Cromatografia Líquida/veterinária , Espectrometria de Massas em Tandem/veterinária , Pólen , Surtos de Doenças/veterinária , Doenças dos Bovinos/patologia , Doenças dos Ovinos/patologia
8.
Biochim Biophys Acta ; 1824(6): 802-12, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22484439

RESUMO

The enzyme cellobiose dehydrogenase (CDH) is of considerable interest, not only for its biotechnological applications, but also its potential biological role in lignocellulosic biomass breakdown. The enzyme catalyzes the oxidation of cellobiose and other cellodextrins, utilizing a variety of one- and two-electron acceptors, although the electron acceptor employed in nature is still unknown. In this study we show that a CDH is present in the secretome of the thermophilic ascomycete Thielavia terrestris when grown with cellulose, along with a mixture of cellulases and hemicellulases capable of breaking down lignocellulosic biomass. We report the cloning of this T. terrestris CDH gene (cbdA), its recombinant expression in Aspergillus oryzae, and purification and characterization of the T. terrestris CDH protein (TtCDH). The TtCDH shows spectral properties and enzyme activity similar to other characterized CDH enzymes. Substrate specificity was determined for a number of carbohydrate electron donors in the presence of the two-electron acceptor 2,6-dichlorophenol-indophenol. The TtCDH also shows dramatic synergy with Thermoascus aurantiacus glycoside hydrolase family 61A protein in the presence of a ß-glucosidase for the cleavage of cellulose.


Assuntos
Desidrogenases de Carboidrato/biossíntese , Celulose/metabolismo , Proteínas Fúngicas/biossíntese , Sordariales/enzimologia , Desidrogenases de Carboidrato/química , Desidrogenases de Carboidrato/genética , Desidrogenases de Carboidrato/metabolismo , Celobiose/química , Celulose/química , Clonagem Molecular , Meios de Cultura , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Cinética , Proteoma/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
9.
Appl Environ Microbiol ; 77(19): 7007-15, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21821740

RESUMO

Several members of the glycoside hydrolase 61 (GH61) family of proteins have recently been shown to dramatically increase the breakdown of lignocellulosic biomass by microbial hydrolytic cellulases. However, purified GH61 proteins have neither demonstrable direct hydrolase activity on various polysaccharide or lignacious components of biomass nor an apparent hydrolase active site. Cellobiose dehydrogenase (CDH) is a secreted flavocytochrome produced by many cellulose-degrading fungi with no well-understood biological function. Here we demonstrate that the binary combination of Thermoascus aurantiacus GH61A (TaGH61A) and Humicola insolens CDH (HiCDH) cleaves cellulose into soluble, oxidized oligosaccharides. TaGH61A-HiCDH activity on cellulose is shown to be nonredundant with the activities of canonical endocellulase and exocellulase enzymes in microcrystalline cellulose cleavage, and while the combination of TaGH61A and HiCDH cleaves highly crystalline bacterial cellulose, it does not cleave soluble cellodextrins. GH61 and CDH proteins are coexpressed and secreted by the thermophilic ascomycete Thielavia terrestris in response to environmental cellulose, and the combined activities of T. terrestris GH61 and T. terrestris CDH are shown to synergize with T. terrestris cellulose hydrolases in the breakdown of cellulose. The action of GH61 and CDH on cellulose may constitute an important, but overlooked, biological oxidoreductive system that functions in microbial lignocellulose degradation and has applications in industrial biomass utilization.


Assuntos
Ascomicetos/enzimologia , Ascomicetos/metabolismo , Desidrogenases de Carboidrato/metabolismo , Celulose/metabolismo , Glicosídeo Hidrolases/metabolismo , Oligossacarídeos/metabolismo , Oxirredução , Especificidade por Substrato
10.
Planta ; 231(3): 677-91, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20012086

RESUMO

Industrial processes to produce ethanol from lignocellulosic materials are available, but improved efficiency is necessary to make them economically viable. One of the limitations for lignocellulosic conversion to ethanol is the inaccessibility of the cellulose and hemicelluloses within the tight cell wall matrix. Ferulates (FA) can cross-link different arabinoxylan molecules in the cell wall of grasses via diferulate and oligoferulate bridges. This complex cross-linking is thought to be a key factor in limiting the biodegradability of grass cell walls and, therefore, the reduction in FA is an attractive target to improve enzyme accessibility to cellulose and hemicelluloses. Unfortunately, our knowledge of the genes responsible for the incorporation of FA to the cell wall is limited. A bioinformatics prediction based on the gene similarities and higher transcript abundance in grasses relative to dicot species suggested that genes from the pfam family PF02458 may act as arabinoxylan feruloyl transferases. We show here that the FA content in the cell walls and the transcript levels of rice genes Os05g08640, Os06g39470, Os01g09010 and Os06g39390, are both higher in the stems than in the leaves. In addition, an RNA interference (RNAi) construct that simultaneously down-regulates transcript levels of these four genes is associated with a significant reduction in FA of the cell walls from the leaves of the transgenic plants relative to the control (19% reduction, P < 0.0001). Therefore, our experimental results in rice support the bioinformatics prediction that members of family PF02458 are involved in the incorporation of FA into the cell wall in grasses.


Assuntos
Parede Celular/metabolismo , Ácidos Cumáricos/metabolismo , Regulação para Baixo , Oryza/genética , Proteínas de Plantas/genética , Transferases/genética , Etiquetas de Sequências Expressas , Oryza/enzimologia , Oryza/metabolismo , Filogenia , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo
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