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1.
Int J Nurs Sci ; 11(1): 46-56, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38352284

RESUMEN

Objectives: Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) patients experience a lower quality of life, frequent exacerbations, and worse pulmonary function. Environmental management is essential in a complex chronic condition, as pollutant exposure can worsen symptoms and increase morbidity and mortality. We aimed to identify evidence that informs nursing interventions in promoting self-management of air quality in asthmatic people with COPD. Methods: We conducted an integrative review in March of 2023. We searched the databases CINAHL, MEDLINE, Academic Search Complete, Cochrane Database of Systematic Reviews (CDSR), Scopus, Web of Science, Joanna Briggs Institute (JBI) Evidence-Based Practice Database, and Google Scholar. We included articles whose participants were adults with asthma, COPD, or both; the intervention was air quality management and the outcome of any exacerbations. We excluded editorials, letters, commentaries, opinion papers, position papers, study protocols, conference abstracts, and reviews. Data extraction and synthesis were performed, categorizing interventions according to nursing actions. Methodological quality assessment was conducted using the JBI Critical Appraisal Checklist tools. The review protocol was registered at Open Science Framework (https://doi.org/10.17605/OSF.IO/5Y4KW). Results: We included five articles from different countries. The interventions promoting air quality self-management for individuals with asthma and COPD included vigilance interventions (health professional regular visits, assessment of symptoms), monitoring interventions (measurement of indoor and outdoor trigger factors), and educational interventions (air quality alerts, allergen avoidance). Policy interventions such as smoke-free policies and comprehensive strategies to improve air quality were also identified. These areas of focus represent critical components of nurses' interventions and can integrate the fundamental patterns of knowing in nursing. Although the studies reveal heterogeneous interventions and the methodological quality is variable, these interventions showed potential for preventing exacerbations, reducing emergency department visits, and minimizing hospitalizations. Conclusions: The study emphasizes the need for a comprehensive approach involving nurses in multidisciplinary teams to air quality self-management. They can use these results to inform their interventions and ways of knowing, benefiting individuals with asthma and COPD. Further research is needed to expand the evidence base and refine these interventions.

2.
An Acad Bras Cienc ; 87(4): 2001-11, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26628022

RESUMEN

We investigated the loss of desiccation tolerance (DT) in Adenanthera pavonina seeds during germination. Seeds were subjected to imbibition for 0, 24, 36, 48, 60 and 81 h, then dried to their initial moisture content (13%), rehydrated and evaluated for survival (resumption of growth and development of normal seedlings) and membrane system integrity (electrolyte leakage). Embryonic axes of seeds subjected only to imbibition during the same early time periods were used to investigate the electrophoretic patterns of heat-stable proteins and the relative nuclear DNA content. In A. pavonina seeds, DT remained unchanged until 36 h of imbibition (resulting in germination and 82% normal seedlings), after which it was progressively lost, and seeds with a protruded radicle length of 1 mm did not withstand dehydration. The loss of desiccation tolerance could not be related to either membrane damage caused by drying or the resumption of the cell cycle during germination. However, the decrease in heat-stable protein contents observed throughout germination may be related to the loss of DT in A. pavonina seeds.


Asunto(s)
Desecación , Fabaceae/fisiología , Germinación/fisiología , Semillas/crecimiento & desarrollo , Adaptación Fisiológica , Fabaceae/clasificación , Semillas/metabolismo , Factores de Tiempo , Agua/metabolismo
3.
An Acad Bras Cienc ; 86(3): 1273-86, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25140505

RESUMEN

This work aimed to characterize the re-induction of desiccation tolerance (DT) in germinated seeds, using polyethylene glycol (PEG 8000). Cell changes were investigated through cytological assays (cell viability and transmission electronic microscopy) as well as DNA integrity during loss and re-establishment of DT. The loss of DT was characterized by drying germinated seeds with different radicle lengths (1, 2, 3, 4 and 5 mm) in silica gel, decreasing the moisture content to ten percentage points intervals, followed by pre-humidification (100% RH / 24 h) and rehydration. To re-induce DT, germinated seeds were treated for 72 h with PEG (-2.04 MPa) and PEG (-2.04 MPa) + ABA (100 µM) before dehydration. Germinated seeds did not tolerate desiccation to 10% moisture content, irrespectively of the radicle length. However, when incubated in PEG, those with 1 and 2 mm long radicle attained 71% and 29% survival, respectively. The PEG+ABA treatment was efficient to re-establish DT in seeds with 1 mm long radicles (100% survival). The ultrastructural assays of the cells of germinated seeds with 2 and 5 mm length confirmed the obtained physiological results. Germinated seeds of C. fissilis constitute a useful tool for desiccation tolerance investigations.


Asunto(s)
Cedrela/crecimiento & desarrollo , Desecación , Germinación/fisiología , Semillas/fisiología , Adaptación Fisiológica/fisiología , Cedrela/fisiología , Cedrela/ultraestructura , Microscopía Electrónica de Rastreo , Polietilenglicoles , Semillas/ultraestructura , Factores de Tiempo
4.
An Acad Bras Cienc ; 85(1): 223-33, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23460438

RESUMEN

This study aims to analyze the maturation and dispersal of Eugenia pyriformis Cambess. seeds produced in different years, and the influence of variation in thermal and hydric environment on seed physical and physiological characteristics at dispersal. Fruits at different developmental stages were harvested in the city of São Paulo between 2003 and 2010, as well as in the cities of Campinas and Lavras, in 2009 and 2010 and analyzed for size and color. The seeds were extracted from the fruits and their dry mass, water content, germination and vigor were assessed. Results showed that seed maturation is unsynchronized to the maturation of the fruit, taking 45 days on average (430 growing degree-days), longer in rainy times or lower temperatures. Seeds with higher physiological quality were produced in rainy years and when the temperature range was larger. We concluded therefore that hydric and thermal environmental variations during development influence the maturation of Eugenia pyriformis seeds and are able to determine the formation cycle and the final seed quality.


Asunto(s)
Germinación/fisiología , Semillas/crecimiento & desarrollo , Syzygium/crecimiento & desarrollo , Syzygium/clasificación , Temperatura , Agua
5.
Ann Bot ; 99(5): 823-30, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17329406

RESUMEN

BACKGROUND AND AIMS: Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species native to the Cerrado of Brazil, in an ecophysiological context. METHODS: Morphological and biochemical characteristics of both embryo and endosperm were monitored during dormancy break and germination at field conditions. Seeds were buried in the field and exhumed monthly for 2 years. Germination, embryo length and endosperm digestion, with endo-beta-mannanase activity as a marker, were measured in exhumed seeds, and scanning electron microscopy was used to detect cell division. The effect of constant low and high temperatures and exogenous gibberellins on dormancy break and germination was also tested under laboratory conditions. KEY RESULTS: After burial in April, A. crassiflora seeds lost their physiological dormancy in the winter months with lowest monthly average minimum temperatures (May-August) prior to the first rainfall of the wet season. The loss of physiological dormancy enabled initiation of embryo growth within the seed during the first 2 months of the rainy season (September-October), resulting in a germination peak in November. Embryo growth occurred mainly through cell expansion but some dividing cells were also observed. Endosperm digestion started at the micropylar side around the embryo and diffused to the rest of the endosperm. Exogenous gibberellins induced both embryo growth and endo-beta-mannanase activity in dormant seeds. CONCLUSIONS: The physiological dormancy component is broken by low temperature and/or temperature fluctuations preceding the rainy season. Subsequent embryo growth and digestion of the endosperm are both likely to be controlled by gibberellins synthesized during the breaking of physiological dormancy. Radicle protrusion thus occurred at the beginning of the rainy season, thereby maximizing the opportunity for seedlings to emerge and establish.


Asunto(s)
Annona/fisiología , Germinación , Annona/anatomía & histología , Annona/embriología , Frío , Germinación/efectos de los fármacos , Giberelinas/farmacología , Estaciones del Año , Semillas/crecimiento & desarrollo , beta-Manosidasa/fisiología
6.
J Exp Bot ; 56(418): 2119-30, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15967778

RESUMEN

Desiccation tolerance (DT) in orthodox seeds is acquired during seed development and lost upon imbibition/germination, purportedly upon the resumption of DNA synthesis in the radicle cells. In the present study, flow cytometric analyses and visualization of microtubules (MTs) in radicle cells of seedlings of Medicago truncatula showed that up to a radicle length of 2 mm, there is neither DNA synthesis nor cell division, which were first detected in radicles with a length of 3 mm. However, DT started to be lost well before the resumption of DNA synthesis, when germinating seeds were dried back. By applying an osmotic treatment with polyethylene glycol (PEG) before dehydration, it was possible to re-establish DT in seedlings with a radicle up to 2 mm long. Dehydration of seedlings with a 2 mm radicle, with or without PEG treatment, caused disassembly of MTs and appearance of tubulin granules. Subsequent pre-humidification led to an almost complete disappearance of both MTs and tubulin granules. Upon rehydration, neither MTs nor tubulin granules were detected in radicle cells of untreated seedlings, while PEG-treated seedlings were able to reconstitute the microtubular cytoskeleton and continue their normal development. Dehydration of untreated seedlings also led to an apoptotic-like DNA fragmentation in radicle cells, while in PEG-treated seedlings DNA integrity was maintained. The results showed that for different cellular components, desiccation-tolerant seedlings may apply distinct strategies to survive dehydration, either by avoidance or further repair of the damages.


Asunto(s)
ADN de Plantas/metabolismo , Medicago truncatula/fisiología , Microtúbulos/fisiología , Semillas/fisiología , Adaptación Fisiológica , Deshidratación , Germinación/fisiología , Medicago truncatula/metabolismo , Medicago truncatula/ultraestructura , Plantones/fisiología , Plantones/ultraestructura , Semillas/metabolismo , Semillas/ultraestructura
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