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1.
Biotechnol Lett ; 46(3): 409-430, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38416309

RESUMO

One of the four cutinases encoded in the Aspergillus nidulans genome, ANCUT1, is described here. Culture conditions were evaluated, and it was found that this enzyme is produced only when cutin is present in the culture medium, unlike the previously described ANCUT2, with which it shares 62% amino acid identity. The differences between them include the fact that ANCUT1 is a smaller enzyme, with experimental molecular weight and pI values of 22 kDa and 6, respectively. It shows maximum activity at pH 9 and 60 °C under assayed conditions and retains more than 60% of activity after incubation for 1 h at 60 °C in a wide range of pH values (6-10) after incubations of 1 or 3 h. It has a higher activity towards medium-chain esters and can modify long-chain length hydroxylated fatty acids constituting cutin. Its substrate specificity properties allow the lipophilization of alkyl coumarates, valuable antioxidants and its thermoalkaline behavior, which competes favorably with other fungal cutinases, suggests it may be useful in many more applications.


Assuntos
Aspergillus nidulans , Hidrolases de Éster Carboxílico , Aspergillus nidulans/genética , Aspergillus nidulans/enzimologia , Especificidade por Substrato , Concentração de Íons de Hidrogênio , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/química , Temperatura , Peso Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Estabilidade Enzimática , Meios de Cultura/química
2.
J Surg Oncol ; 127(6): 1054-1061, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36821093

RESUMO

Patients with cancer facing complex and invasive urologic and gynecologic cancer surgery often experience symptoms and rapid declines in functional capacity postoperatively. Remote patient monitoring that leverages patient-generated health data is a potential approach to assess and promote postoperative recovery. This integrative review aims to provide an overview of the current literature and research on remote patient monitoring in gynecologic and urologic surgical oncology.


Assuntos
Neoplasias dos Genitais Femininos , Oncologia Cirúrgica , Feminino , Humanos , Procedimentos Cirúrgicos em Ginecologia , Monitorização Fisiológica , Neoplasias dos Genitais Femininos/cirurgia
3.
Ann Bot ; 124(1): 15-26, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30715148

RESUMO

BACKGROUND AND AIM: Quaternary glaciations strongly affected the distribution of species from arid and semi-arid environments, as temperature drops were accompanied by strong fluctuations in rainfall. In this study, we examined the response of xerophytic species to glacial cycles, determining the genetic patterns and climatic niche of Echinopsis chiloensis var. chiloensis, an endemic columnar cactus of arid and semi-arid regions of Chile. METHODS: We analysed 11 polymorphic microsatellites for 130 individuals from 13 populations distributed across the entire distribution of the species. We examined genetic diversity and structure, identified possible patterns of isolation by distance (IBD) and tested two competing population history scenarios using Approximate Bayesian Computation. The first scenario assumes a constant population size while the second includes a bottleneck in the southern population. The latter scenario assumed that the southernmost populations experienced a strong contraction during glaciation, followed by a postglacial expansion; by contrast, the area of the northernmost populations remained as a stable refugium. We also used ecological niche modelling (ENM) to evaluate the location and extension of suitable areas during the Last Glacial Maximum (LGM) and the mid-Holocene. KEY RESULTS: We found a decline in genetic diversity towards high latitudes and a significant IBD pattern that together with ENM predictions suggest that E. chiloensis var. chiloensis experienced range contraction northwards during wet-cold conditions of the LGM, followed by expansion during aridification of the mid-Holocene. In addition to IBD, we detected the presence of a strong barrier to gene flow at 32°30'S, which according to coalescence analysis occurred 44 kyr BP. The resulting genetic clusters differed in realized climatic niche, particularly in the variables related to precipitation. CONCLUSIONS: Our results suggest that the cactus E. chiloensis var. chiloensis experienced range contraction and fragmentation during the wet-cold conditions of the LGM, which may have facilitated ecological differentiation between northern and southern populations, promoting incipient speciation.


Assuntos
Variação Genética , Refúgio de Vida Selvagem , Teorema de Bayes , Chile , Haplótipos , Filogenia , Filogeografia
4.
J Plant Res ; 131(3): 429-441, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29564658

RESUMO

We present a comparative flower ontogenetic study in five species of the genus Eucryphia with the aim of testing whether differences in the organ number observed can be explained by changes in the meristematic size of floral meristem and floral organs. Species native to Oceania, viz. E. milliganii, E. lucida and E. moorei, have the smallest gynoecia with ca. 6 carpels, while the Chilean E. glutinosa and E. cordifolia present more than ten carpels. E. milliganii has the smallest flower with the lowest stamen number (ca. 50), while the other species produce around 200 stamens and more. Standardized measurements of meristematic sectors were taken in 49 developing flowers that were classified into three well-defined ontogenetic stages. Sizes of meristems varied significantly among species within each developmental stage as revealed by ANOVA analyses. Significant regressions between organ number and corresponding meristem size were consistent with the premise that a larger meristem size prior to organ initiation could be determining for a higher organ number. Flower organogenesis in Eucryphia also involves relevant meristem expansion while the organs are initiated, which results in a particular androecium patterning with a chaotic stamen arrangement. Meristem expansion also appears to be slower but more extensive in species with larger initial meristematic size, suggesting that flower phenotype can be determined in ontogeny by this heterochronic interplay of space and time.


Assuntos
Flores/crescimento & desenvolvimento , Magnoliopsida/crescimento & desenvolvimento , Meristema/crescimento & desenvolvimento , Organogênese Vegetal , Flores/genética , Flores/fisiologia , Flores/ultraestrutura , Magnoliopsida/genética , Magnoliopsida/fisiologia , Magnoliopsida/ultraestrutura , Meristema/genética , Meristema/fisiologia , Meristema/ultraestrutura , Fenótipo
5.
Am J Bot ; 104(10): 1533-1545, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29885223

RESUMO

PREMISE OF THE STUDY: Plant responses to past climate change could have been shaped by life-history traits. Here we explore the influence of life form on the response of xerophytic plants to Quaternary climate fluctuations, through a comparison of genetic patterns of codistributed herbaceous and shrubby lineages of the genus Nolana. METHODS: We reconstructed the phylogeographic history of a herbaceous lineage of three species of Nolana distributed from a northern arid zone (30°S) to a southern wet-temperate (42°S) zone, by sequencing two cpDNA regions. Results were compared with similar data published earlier for a congeneric, codistributed shrubby lineage. KEY RESULTS: We detected significant genetic differentiation among populations. Divergence of all haplotypes occurred during the Pleistocene, between 245 and 62 kyr ago. For both the shrubby and herbaceous lineages, the greatest haplotype diversity was found in their northern range. However, herbs also retained some diversity at higher latitude. Herbaceous populations were less genetically structured and less differentiated than shrubby ones. CONCLUSION: Genetic evidence revealed that both lineages of Nolana survived climate change through the Quaternary, experiencing population collapses and recoveries. Phylogeographic histories present similarities between the two lineages, but also marked differences that can be explained by their differences in life form and life cycle. While the shrubby lineage followed the classical pattern of postglacial expansion toward higher latitudes, species in the herbaceous lineage showed evidence of long-lasting persistence at the southern edge of their current range, suggesting for the first time multiple glacial refugia for a xerophytic plant in southern South America.


Assuntos
Variação Genética , Solanaceae/genética , Mudança Climática , Clima Desértico , Meio Ambiente , Deriva Genética , Haplótipos , Estágios do Ciclo de Vida , Filogeografia , Refúgio de Vida Selvagem , Solanaceae/fisiologia , América do Sul
6.
Ann Bot ; 118(1): 149-58, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27311572

RESUMO

BACKGROUND AND AIMS: Mycorrhizal associations are influenced by abiotic and biotic factors, including climate, soil conditions and the identity of host plants. However, the effect of environmental conditions on orchid mycorrhizal associations remains poorly understood. The present study examined how differences in soil nutrient availability are related to the diversity and composition of mycorrhizal fungi associated with two terrestrial orchid species from central Chile. METHODS: For 12 populations of Bipinnula fimbriata and B. plumosa, OTU (operational taxonomic unit) richness, phylogenetic diversity and community composition of mycorrhizal fungi in root samples were estimated using internal transcribed spacer (ITS) sequences. Then, these mycorrhizal diversity variables were related to soil nutrients and host species using generalized linear models and non-metric multidimensional scaling. KEY RESULTS: Variation in OTU composition of mycorrhizal fungi among sites was explained mainly by orchid host species. Fungi in Tulasnellaceae and Ceratobasidiaceae were isolated from both orchid species, but the former were more frequent in B. fimbriata and the latter in B. plumosa. Soil nutrients and orchid host species had significant effects on OTU richness and phylogenetic diversity. Mycorrhizal diversity decreased in habitats with higher N in both species and increased with P availability only in B. fimbriata CONCLUSIONS: The results suggest that soil nutrient availability modulates orchid mycorrhizal associations and provide support for the hypothesis that specialization is favoured by higher soil nutrient availability. Inter-specific differences in mycorrhizal composition can arise due to a geographical pattern of distribution of orchid mycorrhizal fungi, host preferences for fungal partners or differential performance of mycorrhizal fungi under different nutrient availabilities. Further experiments are needed to evaluate these hypotheses.


Assuntos
Micorrizas/fisiologia , Orchidaceae/microbiologia , Microbiologia do Solo , Solo/química , Chile , Ecossistema , Micorrizas/genética , Nitrogênio/análise , Fósforo/análise , Filogenia
7.
Mol Biol Rep ; 43(12): 1315-1320, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27631640

RESUMO

The aim of this study was to develop microsatellite markers as a tool to study population structure, genetic diversity and effective population size of Echinopsis chiloensis, an endemic cactus from arid and semiarid regions of Central Chile. We developed 12 polymorphic microsatellite markers for E. chiloensis using next-generation sequencing and tested them in 60 individuals from six sites, covering all the latitudinal range of this species. The number of alleles per locus ranged from 3 to 8, while the observed (Ho) and expected (He) heterozygosity ranged from 0.0 to 0.80 and from 0.10 to 0.76, respectively. We also detected significant differences between sites, with FST values ranging from 0.05 to 0.29. Microsatellite markers will enable us to estimate genetic diversity and population structure of E. chiloensis in future ecological and phylogeographic studies.


Assuntos
Cactaceae/genética , Sequenciamento de Nucleotídeos em Larga Escala/normas , Análise de Sequência de DNA/normas , DNA de Plantas/genética , Genes de Plantas , Repetições de Microssatélites , Filogenia , Padrões de Referência
8.
Front Plant Sci ; 15: 1403273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39474225

RESUMO

The Andean uplift and the concomitant aridification drove the rapid diversification of several plant lineages that were able to colonize warmer and drier habitats at low elevations and wetter and colder habitats at high elevations. These transitions may be facilitated by shifts in plant strategies to cope with drought and cold, which in turn can trigger episodes of accelerated species diversification. Here, we used four nuclear DNA markers to infer phylogenetic relationships of 80 Adesmia species of annuals, perennial herbs, shrubs and small shrubs that occur in Chile and Argentina. We reconstructed ancestral states for area, climatic niche and growth form to explore how Andean uplift and aridification promoted Adesmia diversification. We also performed logistic and linear regression analyses between different components of growth form (life span, woodiness and plant height) and climate. Finally, we estimated speciation rates across the phylogeny. Our results suggest that the ancestor of Chilean Adesmia was a perennial herb that probably originated in the high Andes of northern and central Chile. The low elevations of Central Chile were colonized in the late Miocene, whereas the high latitudes of Patagonia and the hyperarid coastal Atacama Desert were colonized repeatedly since Pliocene by lineages with different growth forms. Multiple and bidirectional transitions between annual and perennial habits and between herbaceous and woody habits were detected. These shifts were not correlated with climate, suggesting that the different growth forms are alternative and successful strategies to survive unfavorable seasons of both desert and high Andes. Net diversification analysis indicated a constant rate of diversification, suggesting that the high species diversity of Adesmia that occur in Chile is due to a uniform speciation process rather than to accelerated episodes of speciation.

9.
Sao Paulo Med J ; 142(4): e2023167, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38477734

RESUMO

BACKGROUND: Patients with severe coronavirus disease 2019 (COVID-19) often require hospital admission and experience sequelae such as chronic fatigue or low muscle mass. OBJECTIVE: To analyze the functional capacity of a cohort of patients with severe acute respiratory syndrome coronavirus 2 who required hospitalization. DESIGN AND SETTING: An observational descriptive study was conducted on post-COVID-19 patients referred to the Rehabilitation Department of Gregorio Marañón Hospital (Madrid, SPAIN). METHODS: Cardiorespiratory fitness, muscle strength, body composition, and perception of fatigue and dyspnea were analyzed. Furthermore, the existing correlations between clinical variables and physical conditions were analyzed. RESULTS: Forty-two patients who required hospital admission (80 ± 22.45 days) or intensive care unit (ICU) admission (58 ± 10.52 days) were analyzed. They presented with decreased strength, respiratory capacity, and moderate-to-severe perceived fatigue. Additionally, an inverse correlation was found between right-handgrip strength and days in the ICU, as well as the 6-minute walk test for women. Similarly, strength and fitness were negatively associated with perceived fatigue. CONCLUSIONS: Post-COVID-19 patients showed low muscle function and low levels of physical fitness associated with high perceived fatigue.


Assuntos
COVID-19 , Aptidão Cardiorrespiratória , Feminino , Humanos , Composição Corporal , Progressão da Doença , Força da Mão , Masculino
10.
Oecologia ; 173(3): 625-35, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23576107

RESUMO

The study of functional traits and physiological mechanisms determining species' drought tolerance is important for the prediction of their responses to climatic change. Fog-dependent forest patches in semiarid regions are a good study system with which to gain an understanding of species' responses to increasing aridity and patch fragmentation. Here we measured leaf and hydraulic traits for three dominant species with contrasting distributions within patches in relict, fog-dependent forests in semiarid Chile. In addition, we assessed pressure-volume curve parameters in trees growing at a dry leeward edge and wet patch core. We predicted species would display contrasting suites of traits according to local water availability: from one end favoring water conservation and reducing cavitation risk, and from the opposite end favoring photosynthetic and hydraulic efficiency. Consistent with our hypothesis, we identified a continuum of water use strategies explaining species distribution along a small-scale moisture gradient. Drimys winteri, a tree restricted to the humid core, showed traits allowing efficient water transport and high carbon gain; in contrast, Myrceugenia correifolia, a tree that occurs in the drier patch edges, exhibited traits promoting water conservation and lower gas exchange rates, as well low water potential at turgor loss point. The most widespread species, Aextoxicon punctatum, showed intermediate trait values. Osmotic compensatory mechanism was detected in M. correifolia, but not in A. punctatum. We show that partitioning of the pronounced soil moisture gradients from patch cores to leeward edges among tree species is driven by differential drought tolerance. Such differences indicate that trees have contrasting abilities to cope with future reductions in soil moisture.


Assuntos
Adaptação Biológica/fisiologia , Demografia , Secas , Árvores/fisiologia , Tempo (Meteorologia) , Vento , Análise de Variância , Chile , Folhas de Planta/fisiologia , Transpiração Vegetal/fisiologia , Pressão , Especificidade da Espécie
11.
PhytoKeys ; 188: 83-103, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095294

RESUMO

Nicotianaknightiana is recorded for the first time for the flora of Chile. A new species of Nicotiana, endemic to the coast of the Coquimbo region is described and illustrated. Molecular analysis placed the new species within the N.sect.Paniculatae, as sister to N.cordifolia, an endemic to Juan Fernandez islands. The new species can be considered critically endangered (CR) according to the IUCN categories due to its restricted and fragmented distribution, small population number, and the threat that urbanization and mining activities represent for the conservation of the biodiversity of the area.

12.
Am J Bot ; 98(5): e114-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21613175

RESUMO

PREMISE OF THE STUDY: Seven microsatellite loci were developed for the two closely related high Andean species Schizanthus hookeri and S. grahamii. These species are annual to biannual herbs with zygomorphic and showy flowers that differ in floral morphology, autonomous selfing capacity, and in the identities of major flower visitors. METHODS AND RESULTS: Polymorphisms were evaluated in a total of 45 plants, including individuals from two populations of S. grahamii and one population of S. hookeri. The number of alleles per locus ranged from two to nine in each population. We also tested these loci for cross-amplification in another seven species of the genus. Four primer pairs amplified in these seven species. CONCLUSIONS: Characterized microsatellites are conserved in the closely related species S. hookeri and S. grahamii, and they have enough polymorphism to be used in future studies of their mating systems and genetic structure.


Assuntos
Primers do DNA/genética , DNA de Plantas/genética , Repetições de Microssatélites , Solanaceae/genética , Alelos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético , Especificidade da Espécie
13.
PhytoKeys ; 185: 99-116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34840505

RESUMO

A new species of Calceolariasect.Cheiloncos endemic to central Chile is described. A comparison with the morphologically similar species Calceolariaasperula and Calceolariapetioalaris is made, and a key as well as detailed images to differentiate them is provided. The species is only known from the Natural Sanctuary Cerro El Roble, which is part of the coastal mountain range of central Chile and can be considered as Critically Endangered (CR) under the IUCN categories and criteria.

14.
Front Plant Sci ; 12: 763446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868160

RESUMO

Echinopsis chiloensis is an endemic cactus from Chile, distributed in a temperature and rainfall gradient between 30° and 35° South latitude, with mean temperatures increasing and precipitation decreasing toward the north. It is the main host of the mistletoe Tristerix aphyllus, a holoparasite completely dependent on the cactus for water, carbon, and minerals. In this study, we investigated the consequences of parasitism over the fitness and physiology of this cactus throughout its distribution range and how it is affected by the environment. We measured five functional traits in eight populations latitudinally distributed, the first three only for the host: reproductive fitness, stomatal traits (density and size), and photosynthesis (during winter and summer); and the last two for the host and parasite: stable isotopes (∂13C and ∂15N), and nutrients (carbon and nitrogen content). The results showed a negative effect of parasitism over fitness of infected cacti. However, the higher nitrogen concentrations in cactus tissues toward the south improved overall fitness. Regarding photosynthesis, we only observed a negative effect of parasitism during the dry season (summer), which is also negatively affected by the increase in summer temperatures and decrease in winter rainfall toward the north. There were no differences in nutrient concentration or in the isotopic signature of healthy and infected cacti. Conversely, we observed a higher carbon and lower nitrogen concentration in mistletoes than in cacti regardless of latitude. The loss of temperature seasonality toward the north increases the C:N ratio, and the values between the parasite and its host diverge. ∂15N was similar between parasites and hosts while ∂13C of the parasite was enriched when compared to its host. Overall, the infection by T. aphyllus affects Echinopsis chiloensis fitness but showed no strong effects over the cactus physiology, except for the summer photosynthesis. Therefore, our data revealed that E. chiloensis response to T. aphyllus infection is sensitive to environmental changes in a way that could be strongly impacted by the desertification projected for this area due to climate change.

15.
Int Wound J ; 7(3): 191-3, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20602649

RESUMO

The aim of this work was to dynamically study pressure variations exerted by elastic compression stockings during walking. While study participants walked, the pressure variations at the interface between elastic stockings and the skin were measured dynamically. Three healthy individuals wearing 10/20 and 20/30 elastic compression stockings manufactured by Sigvaris((R)) (Jundiai, São Paulo-Brazil) were requested to walk along a course for ten times at a constant speed. For every event, an apparatus specifically developed for the study and programmed to take readings at half-second intervals was used to measure the pressure exerted by the elastic stockings. The pressure exerted by the 10/20 stockings varied between 5 and 32 mmHg and for the 20/30 stockings it varied from 10 to 52 mmHg. Elastic stockings with larger pressures generate larger pressure variations during muscle activity (P-value < 0.001). In conclusion, muscle movements during walking cause the pressure exerted by elastic stockings on the leg to vary; thus, the pressure is not constant but has peaks and troughs according to the type of muscle movement and the gradient of the stockings.


Assuntos
Fenômenos Fisiológicos da Pele , Meias de Compressão , Caminhada/fisiologia , Adulto , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Teste de Materiais/instrumentação , Teste de Materiais/métodos , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Postura/fisiologia , Pressão , Meias de Compressão/normas
16.
Plants (Basel) ; 9(10)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081098

RESUMO

One of the most common evolutionary transitions in angiosperms is the reproductive change from outcrossing to selfing, commonly associated with changes in floral biology and genetic diversity. Here, we aim to test whether self-compatibility leads to a reduction of floral traits and genetic diversity. For this, we experimentally estimate levels of self-compatibility, measure three floral traits and estimate four genetic diversity parameters using nine microsatellites in nine Calceolaria species. Our analysis indicated that four of the study species were self-incompatible. In addition, we found that self-compatible species did not show a reduction in floral traits size, but rather displayed larger corolla and elaiophore areas. Our analyses of genetic diversity identified larger allele number and observed heterozygosity in selfers than in outcrossers, but did not find larger inbreeding in the self-compatible species. Even though our results contradict our expectations, in the case of Calceolaria, their high dependence on only two genera of oil-bees puts the genus in a vulnerable reproductive position, probably facilitating the evolution of reproductive assurance mechanisms in the absence of pollinators. As a result, plants maintain their pollinator attraction traits while evolving the ability to self, possibly in a delayed way.

17.
Front Plant Sci ; 11: 714, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582248

RESUMO

Understanding why some plant lineages move from one climatic region to another is a mayor goal of evolutionary biology. In the southern Andes plant lineages that have migrated along mountain ranges tracking cold-humid climates coexist with lineages that have shifted repeatedly between warm-arid at low elevations and cold habitats at high elevations. Transitions between habitats might be facilitated by the acquisition of common traits favoring a resource-conservative strategy that copes with drought resulting from either low precipitation or extreme cold. Alternatively, transitions might be accompanied by phenotypic divergence and accelerated evolution of plant traits, which in turn may depend on the level of coordination among them. Reduced integration and evolution of traits in modules are expected to increase evolutionary rates of traits, allowing diversification in contrasting climates. To examine these hypotheses, we conducted a comparative study in the herbaceous genus Leucheria. We reconstructed ancestral habitat states using Maximum Likelihood and a previously published phylogeny. We performed a Phylogenetic Principal Components Analysis on traits, and then we tested the relationship between PC axes, habitat and climate using Phylogenetic Generalized Least Squares (PGLS). Finally, we compared the evolutionary rates of traits, and the levels of modularity among the three main Clades of Leucheria. Our results suggest that the genus originated at high elevations and later repeatedly colonized arid-semiarid shrublands and humid-forest at lower elevations. PGLS analysis suggested that transitions between habitats were accompanied by shifts in plant strategies: cold habitats at high elevations favored the evolution of traits related to a conservative-resource strategy (thicker and dissected leaves, with high mass per area, and high biomass allocation to roots), whereas warm-arid habitats at lower elevations favored traits related to an acquisitive-resource strategy. As expected, we detected higher levels of modularity in the clades that switched repeatedly between habitats, but higher modularity was not associated with accelerated rates of trait evolution.

18.
Front Plant Sci ; 10: 1595, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921244

RESUMO

Angiosperms are highly diverse in their reproductive systems, including predominantly selfing, exclusive outcrossing, and mixed mating systems. Even though selfing can have negative consequences on natural populations, it has been proposed that plants having a predominantly selfing strategy are also associated with fast development strategies through time limitation mechanisms that allow them to complete their life cycle before the onset of severe drought. This relationship might be affected by the challenges imposed by global change, such as a decrease in pollinator availability and the earlier and more severe onset of droughts. In this work, our aim was to investigate whether selfing is correlated with a dehydration avoidance strategy, and how this could affect drought resistance and survival in two species with different types of selfing: pollinator-independent delayed selfing (Schizanthus grahamii) and pollinator-dependent selfing (Schizanthus hookeri), representing a gradient in selfing rates. We hypothesize that delayed selfing species and highly selfing populations will show "fast" plant traits whereas we will find no pattern in more outcrossed populations of the pollinator-dependent species. However, we predicted that high selfing populations would have lower survival rates when exposed to chronic drought early in their development since fast traits imply physiological compromises that will affect their drought survival. To evaluate these hypotheses, we characterized different physiological and morphological traits in response to two contrasting treatments (moist and dry) in a total of six populations of the two species. We found a relationship between the delayed selfing species and a dehydration avoidance strategy and also with low drought survival. Our work offers evidence to support the importance of abiotic factors, such as drought, on the possible variation in selfing rates on natural populations, and the effect that this mating system could have in their ability to face new environmental conditions such as those imposed by climate change.

19.
São Paulo med. j ; São Paulo med. j;142(4): e2023167, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1536911

RESUMO

ABSTRACT BACKGROUND: Patients with severe coronavirus disease 2019 (COVID-19) often require hospital admission and experience sequelae such as chronic fatigue or low muscle mass. OBJECTIVE: To analyze the functional capacity of a cohort of patients with severe acute respiratory syndrome coronavirus 2 who required hospitalization. DESIGN AND SETTING: An observational descriptive study was conducted on post-COVID-19 patients referred to the Rehabilitation Department of Gregorio Marañón Hospital (Madrid, SPAIN). METHODS: Cardiorespiratory fitness, muscle strength, body composition, and perception of fatigue and dyspnea were analyzed. Furthermore, the existing correlations between clinical variables and physical conditions were analyzed. RESULTS: Forty-two patients who required hospital admission (80 ± 22.45 days) or intensive care unit (ICU) admission (58 ± 10.52 days) were analyzed. They presented with decreased strength, respiratory capacity, and moderate-to-severe perceived fatigue. Additionally, an inverse correlation was found between right-handgrip strength and days in the ICU, as well as the 6-minute walk test for women. Similarly, strength and fitness were negatively associated with perceived fatigue. CONCLUSIONS: Post-COVID-19 patients showed low muscle function and low levels of physical fitness associated with high perceived fatigue.

20.
BMJ Glob Health ; 3(5): e000862, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30397514

RESUMO

By early-2016, the international community began to pressure Brazil for a stronger policy response to Zika. In contrast to what was seen in the past, however, these international pressures did not elicit such a response. In this article, we explore why this was the case, reviewing the government's policy response and the broader political and economic context shaping this response. The authors used single case study analysis and qualitative sources, such as books, journal articles, and government policy reports to support their empirical claims. We found that despite increased international pressures from the WHO, domestic political factors and economic recession hampered the government's ability to strengthen its health systems response to Zika. Consequently, those states most afflicted by Zika have seen policy initiatives that lack sufficient funding, administrative and human resource capacity. This study revealed that despite a government's deep foreign policy history of positively responding to international pressures through a stronger policy response to health epidemics, a sudden change in government, rising political instability, and economic recession can motivate governments to abandon this foreign policy tradition and undermine its response to new public health threats.

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