Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 95
Filtrar
1.
Plant Biol (Stuttg) ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967240

RESUMO

Neotropical seasonal dry forest (NSDF) is one of the most threatened ecosystems according to global climate change predictions. Nonetheless, few studies have evaluated the global climate change impacts on diversity patterns of NSDF plants. The lack of whole biome-scale approaches restricts our understanding of global climate change consequences in the high beta-diverse NSDF. We analysed the impact of global climate change on species distribution ranges, species richness, and assemblage composition (beta diversity) for 1,178 NSDF species. We used five representative plant families (in terms of abundance, dominance, and endemism) within the NSDF: Cactaceae, Capparaceae, Fabaceae, Malvaceae, and Zygophyllaceae. We reconstructed potential species distributions in the present and future (2040-2080), considering an intermediate Shared Socioeconomic Pathway and two dispersal ability assumptions on the taxa. Using a resource use scores index, we related climate-induced range contractions with species' water stress tolerance. Even under a favourable dispersal scenario, species distribution and richness showed future significant declines across those sites where mean temperature and precipitation seasonality are expected to increase. Further, changes in species range distribution in the future correlated positively with potential use of resources in Fabaceae. Results suggest that biotic heterogenization will likely be the short-term outcome at biome scale under dispersal limitations. Nonetheless, by 2080, the prevailing effect under both dispersal assumptions will be homogenization, even within floristic nuclei. This information is critical for further defining new areas worth protecting and future planning of mitigation actions for both species and the whole biome.

2.
Proc Biol Sci ; 291(2025): 20240266, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38920109

RESUMO

Climate change has physiological consequences on organisms, ecosystems and human societies, surpassing the pace of organismal adaptation. Hibernating mammals are particularly vulnerable as winter survival is determined by short-term physiological changes triggered by temperature. In these animals, winter temperatures cannot surpass a certain threshold, above which hibernators arouse from torpor, increasing several fold their energy needs when food is unavailable. Here, we parameterized a numerical model predicting energy consumption in heterothermic species and modelled winter survival at different climate change scenarios. As a model species, we used the arboreal marsupial monito del monte (genus Dromiciops), which is recognized as one of the few South American hibernators. We modelled four climate change scenarios (from optimistic to pessimistic) based on IPCC projections, predicting that northern and coastal populations (Dromiciops bozinovici) will decline because the minimum number of cold days needed to survive the winter will not be attained. These populations are also the most affected by habitat fragmentation and changes in land use. Conversely, Andean and other highland populations, in cooler environments, are predicted to persist and thrive. Given the widespread presence of hibernating mammals around the world, models based on simple physiological parameters, such as this one, are becoming essential for predicting species responses to warming in the short term.


Assuntos
Mudança Climática , Hibernação , Marsupiais , Estações do Ano , Animais , Marsupiais/fisiologia , Dinâmica Populacional , Modelos Biológicos , Ecossistema , Metabolismo Energético
3.
Sci Total Environ ; 924: 171695, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38485025

RESUMO

Increasing aridity associated with climate change may lead to the crossing of critical ecosystem thresholds in drylands, compromising ecosystem services for millions of people. In this context, finding tools to detect at early stages the effects of increasing aridity on ecosystems is extremely urgent to avoid irreversible damage. Here, we assess shifts in plant community functional structure along a spatial aridity gradient in tropical dryland (Brazilian Caatinga), to select the most appropriate plant functional groups as ecological indicators likely useful to predict temporal ecosystem trajectories in response to aridity. We identified seven plant functional groups based on 13 functional traits associated with plant establishment, defense, regeneration, and dispersal, whose relative abundances changed, linearly and non-linearly, with increasing aridity, showing either increasing or decreasing trends. Of particular importance is the increase in abundance of plants with high chemical defense and Crassulacean Acid Metabolism (CAM) photosynthetic pathway, with increasing aridity. We propose the use of these functional groups as early warning indicators to detect aridity impacts on these dryland ecosystems and shifts in ecosystem functioning. This information can also be used in the elaboration of mitigation and ecological restoration measures to prevent and revert current and future climate change impacts on tropical dry forests.


Assuntos
Ecossistema , Florestas , Humanos , Plantas/metabolismo , Mudança Climática , Brasil
4.
J Plant Res ; 137(3): 377-393, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369599

RESUMO

The tree genus Dimorphandra (Fabaceae), which contains 26 species divided into three subgenera, was studied using DNA sequence data from six chloroplast genome regions (cpDNA) and the nuclear internal transcribed spacer (ITS). The analyses, which included Bayesian phylogenies and haplotype networks, ancestral area reconstructions, and ecological niche modeling, allowed for exploring the evolutionary history of Dimorphandra. Within the subgenus Phaneropsia, the cpDNA sequence data were more closely-related to species from the genus Mora, while the ITS sequence data displayed a closer phylogenetic relationship with the subgenus Pocillum. This incongruence may be due to incomplete lineage sorting associated with ancient polymorphisms. The Amazonian Dimophandra lineages were highly polymorphic and divergent, while those from the Cerrado and the Atlantic Forest had low levels of polymorphisms. The Amazon likely gave rise to the Dimophandra lineage that produced the Cerrado species, while a Cerrado lineage likely gave rise to the Atlantic Forest species. Habitat shifts were identified as a key factor in shaping the late evolutionary history of Dimorphandra.


Assuntos
Fabaceae , Florestas , Pradaria , Filogenia , Fabaceae/genética , Fabaceae/classificação , DNA de Cloroplastos/genética , Haplótipos , Evolução Biológica , Análise de Sequência de DNA , Genoma de Cloroplastos/genética , Teorema de Bayes , Evolução Molecular , DNA de Plantas/genética , Ecossistema
5.
J Comput Chem ; 45(12): 863-877, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38153839

RESUMO

This work provides a detailed multi-component analysis of aromaticity in monosubstituted (X = CH3, C H 2 - , C H 2 + , NH2, NH-, NH+, OH, O-, and O+) and para-homodisubstituted (X = CH3, CH2, NH2, NH, OH, and O) benzene derivatives. We investigate the effects of substituents using single-reference (B3LYP/DFT) and multireference (CASSCF/MRCI) methods, focusing on structural (HOMA), vibrational (AI(vib)), topological (ELFπ), electronic (MCI), magnetic (NICS), and stability (S0-T1 splitting) properties. The findings reveal that appropriate π-electron-donating and π-electron-accepting substituents with suitable size and symmetry can interact with the π-system of the ring, significantly influencing π-electron delocalization. While the charge factor has a minimal impact on π-electron delocalization, the presence of a pz orbital capable of interacting with the π-electron delocalization is the primary factor leading to a deviation from the typical aromaticity characteristics observed in benzene.

6.
R Soc Open Sci ; 10(10): 230409, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37830015

RESUMO

Azithromycin (AZM) is a macrolide-type antibiotic used to prevent and treat serious infections (mycobacteria or MAC) that significantly inhibit bacterial growth. Knowledge of the predominant conformation in solution is of fundamental importance for advancing our understanding of the intermolecular interactions of AZM with biological targets. We report an extensive density functional theory (DFT) study of plausible AZM structures in solution considering implicit and explicit solvent effects. The best match between the experimental and theoretical nuclear magnetic resonance (NMR) profiles was used to assign the preferred conformer in solution, which was supported by the thermodynamic analysis. Among the 15 distinct AZM structures, conformer M14, having a short intramolecular C6-OH … N H-bond, is predicted to be dominant in water and dimethyl sulfoxide (DMSO) solutions. The results indicated that the X-ray structure backbone is mostly conserved in solution, showing that large flexible molecules with several possible conformations may assume a preferential spatial orientation in solution, which is the molecular structure that ultimately interacts with biological targets.

7.
PeerJ ; 11: e15915, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663285

RESUMO

Intraspecific variation modulates patterns of resource use by species, potentially affecting the structure and stability of food webs. In human-modified landscapes, habitat disturbance modifies trophic interactions and intraspecific niche variation, impacting population persistence. Here, we investigated the relationship of sex, ontogeny, and habitat factors with the trophic niche of Caiman crocodilus in an agricultural landscape. We evaluated temporal variation in the trophic niche parameters using carbon and nitrogen stable isotope analysis from different body tissues. We found that caimans exploit the same carbon and nitrogen pools through time, with low isotopic variability between seasons, partly due to the slow isotope turnover rates of tissues in crocodilians. Conversely, the trophic niche of caimans varied across habitats, but with no evidence of a difference between natural and anthropogenic habitats. It apparently results from the influence of habitat suitability, connectivity, and caiman movements during the foraging. Our findings highlight the broader niches of juvenile caimans relative to adults, possibly in response of territorialism and opportunistic foraging strategy. Although using similar resources, females had a larger niche than males, probably associated with foraging strategies during nesting. Considering the sex and body size categories, caimans occupied distinct isotopic regions in some habitats, indicating apparent niche segregation. Ontogenetic trophic shifts in the isotopes (δ13C and δ15N) depended on sex, leading to resource partitioning that can potentially reduce intraspecific competition. Decision-makers and stakeholders should consider the trophic dynamics of sex and body size groups for the sustainable management and conservation of caiman populations, which implies in the maintenance of wetland habitats and landscape heterogeneity in the Formoso River floodplain.


Assuntos
Agricultura , Jacarés e Crocodilos , Humanos , Adulto , Feminino , Masculino , Animais , Tamanho Corporal , Carbono , Nitrogênio , Isótopos de Nitrogênio
8.
Integr Zool ; 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550887

RESUMO

Diet composition and its ecological drivers are rarely investigated in coexisting closely related species. We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous ecosystem. DNA metabarcoding revealed that the lizards Sceloporus aeneus, S. bicanthalis, S. grammicus, and S. spinosus mostly consumed arthropods of the orders Hemiptera, Araneae, Hymenoptera, and Coleoptera. The terrestrial lizards S. aeneus and S. bicanthalis mostly predated ants and spiders, whereas the arboreal-saxicolous S. grammicus and saxicolous S. spinosus largely consumed grasshoppers and leafhoppers. The taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season, likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional demands. Dietary and phylogenetic composition varied seasonally depending on the species, but only dietary composition varied with altitude. Seasonal dietary turnover was greater in S. spinosus than in S. bicanthalis, suggesting site-specific seasonal variability in prey availability; no other differences among species were observed. S. bicanthalis, which lives at the highest altitude in our study site, displayed interseasonal variation in diet breadth. Dietary differences were correlated with the species' feeding strategies and elevational distribution, which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

9.
R Soc Open Sci ; 10(4): 230229, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37063994

RESUMO

The Cinchona genus is important for humanity due to its ethnobotanical properties, and in particular its ability to prevent and treat malaria. However, there have been historical changes of Cinchona distribution in the tropical Andes that remain undocumented. In the late eighteenth and early nineteenth centuries, several explorers recorded Cinchona precise localities in present-day Colombia and Ecuador, countries which harbour about half of the species of the genus, including C. officinalis. We compare historical and twentieth-century records to evaluate whether elevational ranges, mean elevation and latitude varied between the two periods. A large expansion of 662.5 m in average elevation for Cinchona and 792.5 m in elevational range for C. officinalis was found. These findings have implications for the conservation of economically important species and help us understand the impacts of the Anthropocene over time.

10.
Clocks Sleep ; 5(1): 47-61, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36810843

RESUMO

Environmental, social, and behavioral variables influence sleep timing and duration. Using wrist-worn accelerometers, we recorded 31 dancers (age = 22.6 ± 3.5) for 17 days and who trained either in the morning (n = 15) or in the late evening (n = 16). We estimated the dancers' daily sleep pattern: onset, end, and duration. In addition, their minutes of moderate-to-vigorous physical activity (MVPA) and mean light illuminance were also calculated daily and for the morning-shift and late-evening-shift time windows. On training days, the shifts involved differences in sleep timing, alarm-driven waking frequency, and the pattern of light exposure and MVPA duration. Sleep was strongly advanced when dancers trained in the morning and when alarms were used, while morning light had a low influence. Sleep was delayed when dancers were more exposed to light and displayed longer MVPA during the late evening. Sleep duration was strongly reduced on weekends and when alarms were used. A small reduction in sleep duration was also observed when morning illuminance was lower or when late evening MVPA was longer. Training in shifts influenced the timing of environmental and behavioral factors, which added up to shape dancers' sleep timing and duration.

11.
REVISA (Online) ; 12(1): 62-79, 2023.
Artigo em Português | LILACS | ID: biblio-1417142

RESUMO

Objetivo: Analisar as evidências científicas dos principais fatores que alteram a qualidade do sono e as consequências na vida de enfermeiros que atuam na unidade de terapia intensiva. Método: Revisão integrativa da literatura, realizado de dezembro de 2021 à maio de 2022. A busca efetuou-se, através da Plataforma BVS, SciELO e CAPES utilizando os descritores: sono, "trabalho em turnos", enfermagem e "unidades de terapia intensiva", combinados ao operador booleano "AND". Resultados: Existe uma relação muito próxima entre a exposição diária a fatores estressores relacionados ao ambiente desgastante e cansativo que é a UTI, a qualidade do sono dos enfermeiros que trabalham em turnos e as consequências na vida destes. Uma vez que o padrão do ciclo do sonovigília é alterado toda qualidade do sono sofre alterações irreparáveis influenciando diretamente com a qualidade de vida social e familiar trazendo prejuízo a saúde do trabalhador. Conclusão: Sendo assim um indicativo que os danos causados pela alteração do ciclo sono-vigília tanto são prejudicial à saúde psico-social do enfermeiro como a qualidade da assistência prestada por esse trabalhador aos pacientes que estão aos seus cuidados.


Objective: To analyze the scientific evidence of principais factors that alter the quality of sleep and the consequences in the lives of nurses working in the intensive care unit. Method: Integrative literature review, conducted from December 2021 to May 2022. The search was carried out, through the VHL, SciELO and CAPES Platform using the descriptors: sleep, "shift work", nursing and "intensive care units", combined with the Boolean operator "AND". Results: There is a very close relationship between daily exposure to stressors related to the exhausting and tiring environment that is the ICU, the quality of sleep of nurses working shifts and the consequences in their lives. Since the sleep-wake cycle pattern is altered all sleep quality undergoes irreparable changes directly influencing the social and family quality of life, harming the worker's health. Conclusion: Thus, it is indicative that the damage caused by the change in the sleep-wake cycle is both harmful to the psycho-social health of nurses and the quality of care provided by this worker to patients who are in their care.


Objetivo: Analizar la evidencia científica de los factores de principais que alteran la calidad del sueño y las consecuencias en la vida de las enfermeras que trabajan en la unidad de cuidados intensivos. Método: Revisión integradora de la literatura, realizada desde diciembre de 2021 hasta mayo de 2022. La búsqueda se realizó, a través de la Plataforma BVS, SciELO y CAPES utilizando los descriptores: sueño, "trabajo por turnos", enfermería y "unidades de cuidados intensivos", combinados con el operador booleano "AND". Resultados: Existe una relación muy estrecha entre la exposición diaria a factores estresantes relacionados con el ambiente agotador y agotador que es la UCI, la calidad del sueño de las enfermeras que trabajan por turnos y las consecuencias en sus vidas. Dado que el patrón del ciclo sueño-vigilia se altera, toda la calidad del sueño sufre cambios irreparables que influyen directamente en la calidad de vida social y familiar, perjudicando la salud del trabajador. Conclusión: Por lo tanto, es indicativo de que el daño causado por el cambio en el ciclo sueño-vigilia es perjudicial tanto para la salud psicosocial de las enfermeras como para la calidad de la atención prestada por este trabajador a los pacientes que están a su cargo.


Assuntos
Qualidade do Sono , Jornada de Trabalho em Turnos , Unidades de Terapia Intensiva , Enfermeiros
12.
Front Plant Sci ; 13: 1005557, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544882

RESUMO

Introduction: The severe Asian form of huanglongbing (HLB), a vascular disease associated with the phloem-limited bacterium 'Candidatus Liberibacter asiaticus', is transmitted by the Asian citrus psyllid (ACP) Diaphorina citri. Disease impacts are known for sweet oranges and acid limes but not lemons. Methods: In a five-year study (2017-2021) we compared yield and fruit quality between naturally-infected and healthy 5-yr-old trees of Sicilian lemon 'Femminello', and shoot phenology on both lemon and 'Valencia' orange, both grafted onto 'Swingle' citrumelo, grown in southeastern São Paulo State, Brazil. HLB severity (percentage of tree canopy area with HLB symptoms) was assessed every 3-4 months, fruit yield and quality in May (2017 to 2019) or June/July (2020-2021), and vegetative and reproductive shoots fortnightly on 50-cm-long branches. The development of ACP on one-year-old seedlings of five lemon varieties, 'Tahiti' acid lime, 'Valencia' orange, and orange jasmine was evaluated. Results: Symptoms increased from 11% in 2017 to 64% in 2021, and a monomolecular model estimated 10 years for symptoms to occupy >90% of the tree canopy. On average, production of trees with symptom on 20%, 50% or 80% of the canopy respectively dropped by 18%, 38%, and 53% compared to healthy trees. Fruits of symptomatic branches of lemons were 4.22% lighter and the number of dropped fruits did not correlate with symptom severity. Flushing on symptomatic branches started earlier by 15 to 55 days as compared to the healthy branches of lemon and orange. On diseased trees, vegetative and reproductive shoots respectively increased by 24.5% and 17.5% on lemon and by 67.2% and 70.6% on sweet orange, but fruit set was reduced by 12.9% and 19.7% on lemon and orange trees, respectively. ACP reproduced similarly on all tested plants. Discussion: The fast symptom progress, significant yield reduction, and earlier flushing on diseased trees, providing conditions highly favorable for the pathogen to spread, reinforce the need of prompt diseased tree removal and frequent ACP preventive control to manage HLB in lemons as in any other citrus crop.

13.
PeerJ ; 10: e14019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36168438

RESUMO

Background: Maize (Zea mays L.) is a staple crop cultivated on a global scale. However, its ability to feed the rapidly growing human population may be impaired by climate change, especially if it has low climatic niche and range lability. One important question requiring clarification is therefore whether maize shows high niche and range lability. Methods: We used the COUE scheme (a unified terminology representing niche centroid shift, overlap, unfilling and expansion) and species distribution models to study the niche and range changes between maize and its wild progenitors using occurrence records of maize, lowland teosinte (Zea mays ssp. parviglumis) and highland teosinte (Zea mays ssp. mexicana), respectively, as well as explore the mechanisms underlying the niche and range changes. Results: In contrast to maize in Mexico, maize did not conserve its niche inherited from lowland and highland teosinte at the global scale. The niche breadth of maize at the global scale was wider than that of its wild progenitors (ca. 5.21 and 3.53 times wider compared with lowland and highland teosinte, respectively). Compared with its wild progenitors, maize at global scale can survive in regions with colder, wetter climatic conditions, as well as with wider ranges of climatic variables (ca. 4.51 and 2.40 times wider compared with lowland and highland teosinte, respectively). The niche changes of maize were largely driven by human introduction and cultivation, which have exposed maize to climatic conditions different from those experienced by its wild progenitors. Small changes in niche breadth had large effects on the magnitude of range shifts; changes in niche breadth thus merit increased attention. Discussion: Our results demonstrate that maize shows wide climatic niche and range lability, and this substantially expanded its realized niche and potential range. Our findings also suggest that niche and range shifts probably triggered by natural and artificial selection in cultivation may enable maize to become a global staple crop to feed the growing population and adapting to changing climatic conditions. Future analyses are needed to determine the limits of the novel conditions that maize can tolerate, especially relative to projected climate change.


Assuntos
Zea mays , Humanos , México
14.
Biology (Basel) ; 11(7)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-36101386

RESUMO

In this study, otolith geochemical signatures (Element:Ca ratios) were used to investigate the long-term spatial shifts of the population structure of Isopisthus parvipinnis, Bigtooth corvina, an economically and ecologically important Brazilian fish species. Two-hundred and ninety-seven juvenile individuals from historical (1975) and contemporary (2018/2019) samples were collected in five subareas [São Paulo: North-NSP, Center-CSP and South-SSP; Paraná (PR) and Santa Catarina (SC)] of the shallow waters off the coast of the South Brazil Bight were analyzed. The main informative single elements were Co:Ca, Cu:Ca, Li:Ca, Mg:Ca, Mn:Ca, Ni:Ca, Na:Ca, and Rb:Ca. Multivariate analysis showed spatial differences in otolith chemical composition over the years. Samples from 1975 presented an overall low reclassification rate (58%), suggesting the existence of two population units: (1) SP + PR; and (2) SC. However, samples from 2018/2019 discriminated four distinct population units with a good overall reclassification (80%): (1) NSP; (2) CSP; (3) SSP + PR; and (4) SC. This spatial differentiation on the geochemical signatures probably reflects the effects of long-term temporal variability in oceanographic conditions, anthropogenic influence, and climate change on this coastal ecosystem. The data also corroborate and refines the population structure scenario of I. parvipinnis recently described using complementary phenotypic tags.

15.
Front Plant Sci ; 13: 924922, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35982706

RESUMO

Full plastome sequences for land plants have become readily accessible thanks to the development of Next Generation Sequencing (NGS) techniques and powerful bioinformatic tools. Despite this vast amount of genomic data, some lineages remain understudied. Full plastome sequences from the highly diverse (>1,500 spp.) subfamily Tillandsioideae (Bromeliaceae, Poales) have been published for only three (i.e., Guzmania, Tillandsia, and Vriesea) out of 22 currently recognized genera. Here, we focus on core Tillandsioideae, a clade within subfamily Tillandsioideae, and explore the contribution of individual plastid markers and data categories to inform deep divergences of a plastome phylogeny. We generated 37 high quality plastome assemblies and performed a comparative analysis in terms of plastome structure, size, gene content and order, GC content, as well as number and type of repeat motifs. Using the obtained phylogenetic context, we reconstructed the evolution of these plastome attributes and assessed if significant shifts on the evolutionary traits' rates have occurred in the evolution of the core Tillandsioideae. Our results agree with previously published phylogenetic hypotheses based on plastid data, providing stronger statistical support for some recalcitrant nodes. However, phylogenetic discordance with previously published nuclear marker-based hypotheses was found. Several plastid markers that have been consistently used to address phylogenetic relationships within Tillandsioideae were highly informative for the retrieved plastome phylogeny and further loci are here identified as promising additional markers for future studies. New lineage-specific plastome rearrangements were found to support recently adopted taxonomic groups, including large inversions, as well as expansions and contractions of the inverted repeats. Evolutionary trait rate shifts associated with changes in size and GC content of the plastome regions were found across the phylogeny of core Tillandsioideae.

16.
G Ital Med Lav Ergon ; 44(3): 352-359, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36622823

RESUMO

SUMMARY: Background. Aim of our study was to measure the first responses to hypobaric hypoxia: changes in ventilation minute, heart rate, and hemoglobin saturation which are important parameters involved in the health of mine-workers at high-altitude. Material and Methods. We develop a study of parameters mentioned on Chilean miners working in an underground mine at high altitude, between 3.070 and 3.656 masl, in an unusual shift system consisting of 12-hour daily work during 4 days, and consecutive 4 resting days. The results obtained at high altitude are contrasted with the corresponding for clerks working at 800 masl. Results. Either miners who has work less than 6 months at HA as those who are exposed at their workplace to contaminants, as diesel and others, show Hemoglobin Saturation below 90%. Heart Rate increases in response to exposure to acute and/or chronic hypoxia at high altitude. Miners during their resting period at 800 masl or less show an average heart rate lower than clerks no exposed to high altitude. Average Minute Volume of miners at high altitude, on each and every day of the shift, is higher than the mean volume of clerks at 800 masl. Conclusions. The most of studied miners present acclimatization responses at high altitude in all the studied parameters. The increase in Minute Volume implies a risky condition due to the increase of inhaled toxic inherent to the production process. It appears as an urgency to study the combined effects of hypobaric at high altitude and toxics present at the underground mine.


Assuntos
Altitude , Hipóxia , Humanos , Mineração , Aclimatação/fisiologia , Hemoglobinas
17.
Nat Prod Res ; 36(7): 1904-1908, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32911984

RESUMO

Hypericin (HYP) is an active compound of Hypericum perforatum. Associated with photodynamic therapy (PDT), HYP has shown a broad therapeutic potential against microorganisms and cancer cells. Due to the low water solubility of HYP, its application in the biological medium becomes limited. To solve this limitation, our research group has been used copolymeric micelles to carrier HYP with high efficiency. However, there is no elucidated mechanism for HYP delivery mediated by copolymeric micelles. In this sense, we believed that the study of binding-sites of copolymeric micelles and HYP is the first step to its understanding. For this purpose, in this work, we employed 1D and 2D NMR techniques to investigate the behaviour of HYP-loaded P84 micelles in different concentrations . 1D and 2D NMR analysis revealed that HYP molecules were arrangement in a π-stacked aggregation form with a specific location on the core of P84 micelles.


Assuntos
Perileno , Fotoquimioterapia , Antracenos , Micelas , Perileno/análogos & derivados , Fotoquimioterapia/métodos
18.
Texto & contexto enferm ; 31: e20210346, 2022. tab, graf
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: biblio-1377405

RESUMO

ABSTRACT Objective: to analyze the association between sleep quality, health symptoms and the physical, psychological and social effects of work in Nursing professionals working the night shift. Method: a cross-sectional study conducted with Nursing professionals working the night shift of a hospital institution. The instruments used were a socio-occupational and health symptoms questionnaire, the Assessment Scale for Work-Related Harms, and the Pittsburgh Sleep Quality Index. Data were collected between September 2017 and April 2018.The analysis was performed by means of descriptive and analytical statistics. Results: a total of 139 workers took part in the study and a statistical difference was identified between poor sleep quality and the female gender and physical illness variables and health symptoms such as appetite disorder, sensation of indigestion, flatulence, insomnia, difficulty concentrating, unhappiness, sensation of decreased self-esteem and mood lability. Conclusion: it was verified that Nursing professionals working the night shift experienced poor sleep quality, and that this relationship exerts an impact on physical, psychological and social health. Interventions targeted at raising awareness about sleep hygiene can promote better outcomes in these individuals' health.


RESUMEN Objetivo: analizar la asociación entre la calidad del sueño, síntomas de salud y los efectos físicos, psicológicos y sociales del trabajo en profesionales de Enfermería que se desempeñaban en el turno nocturno. Método: estudio transversal, realizado con trabajadores de Enfermería que se desempeñaban en el turno nocturno de una institución hospitalaria. Se utilizaron los siguientes instrumentos: un cuestionario sociolaboral y de síntomas de salud, la Escala de Evaluación de los Daños Relacionados al Trabajo y el Índice de Calidad del Sueño de Pittsburgh. Los dados se recopilaron entre septiembre de 2017 y abril de 2018. El análisis se realizó por medio da estadística descriptiva y analítica. Resultados: se contó con la participación de 139 trabajadores y se identificó una diferencia estadística entre calidad de sueño deficiente y las variables sexo femenino y padecimiento físico, síntomas de salud como trastornos del apetito, sensación de indigestión, flatulencia, insomnio, dificultad para concentrarse, desdicha, sensación de disminución de la autoestima y labilidad en el estado de ánimo. Conclusión: se verificó que los trabajadores de Enfermería que se desempeñaban en el turno nocturno presentaron calidad de sueño deficiente, y esa relación afecta la salud física, psicológica y social. Intervenciones con el objetivo de generar conciencia sobre la higiene del sueño pueden promover mejores resultados en la salud de estas personas.


RESUMO Objetivo: analisar a associação entre a qualidade do sono, sintomas de saúde e os efeitos físicos, psicológicos e sociais do trabalho em trabalhadores de enfermagem que atuavam no turno noturno. Método: estudo transversal, realizado com trabalhadores de enfermagem que atuavam em instituição hospitalar no turno noturno. Utilizaram-se como instrumentos questionário sociolaboral e de sintomas de saúde, Escala de Avaliação dos Danos Relacionados ao Trabalho e o Índice de Qualidade do Sono de Pittsburgh. Os dados foram coletados entre setembro de 2017 e abril de 2018. A análise foi realizada por meio da estatística descritiva e analítica. Resultados: participaram 139 trabalhadores e identificou-se diferença estatística entre qualidade do sono ruim e as variáveis sexo feminino, adoecimento físico e sintomas de saúde como distúrbio de apetite, sensação de má digestão, flatulência, insônia, dificuldade de concentração, infelicidade, sensação de diminuição autoestima e labilidade de humor. Conclusão: constatou-se que os trabalhadores de enfermagem que atuavam no turno noturno experimentavam qualidade do sono ruim, e essa relação impacta na saúde física, psicológica e social. Intervenções visando à conscientização sobre a higiene do sono podem promover melhores resultados na saúde dessas pessoas.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Sono , Estudos Transversais , Jornada de Trabalho em Turnos , Qualidade do Sono , Saúde Ocupacional , Higiene do Sono
19.
Enferm. univ ; 18(3): 314-328, jul.-sep. 2021. tab
Artigo em Espanhol | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-1506191

RESUMO

RESUMEN Introducción Las alteraciones metabólicas se vinculan a los ritmos biológicos, dado que es tos sistemas controlan aspectos fisiológicos como patrones de sueño/vigilia, temperatura corporal, presión arterial y liberación de hormonas endocrinas. Objetivo Identificar la relación entre los componentes del síndrome metabólico y disincro nía circadiana en personal de enfermería de un hospital público. Métodos Estudio correlacional. Muestra censal de 30 profesionales de enfermería de dos turnos. Para la recolección de datos se utilizaron tres cédulas: a) antecedentes biosociode mográficos y laborales; b) síndrome metabólico; c) ciclo circadiano. En el procesamiento de datos se utilizó pruebas Chi-cuadrada, R de Pearson y Rho de Spearman, se verificó el su puesto de normalidad con Shapiro-Wilk. Se contó con autorización del Comité de Ética de la institución de salud y con el consentimiento informado de participantes. Resultados 43.3 % del personal de enfermería cumplió con criterios diagnósticos de síndro me metabólico, 100 % del turno nocturno presentó disincronía circadiana con base en el indicador patrón de sueño. El consumo de alcohol y nivel alto de triglicéridos, mostraron relación positiva estadísticamente significativa con la presencia de insomnio (p ≤ 0.001; p ≤ 0.05). Conclusión El síndrome metabólico es un problema de salud con alta prevalencia entre el personal de enfermería, independientemente del nivel académico o del turno laboral. El peso y los triglicéridos fueron indicadores que mostraron relación con patrones de sueño afectados. Esto enfatiza la importancia de incidir en la prevención y tratamiento del sín drome metabólico como una prioridad en el personal de enfermería, desde la salud laboral.


ABSTRACT Introduction Metabolic alterations are linked to biologic rhythms because these cycles control physiologic patterns including sleep/awake, body temperature, blood pressure, and hormones release. Objective To identify the relationship between the metabolic syndrome components and the circadian alterations among nursing personnel in a public hospital in Mexico. Method This is a correlational study. The sample was constituted of 30 nursing professio nals working in 2 shifts. Data were collected using three registers: a) bio socio-demographic and labor-related backgrounds; b) metabolic syndrome; c) circadian cycle. Chi-square, Pearson's R, Spearman's Rho, and Shapiro-Wilk normality test were calculated. The study approval was granted by the Ethics Committee of the Health Institution. The corresponding informed consent was obtained from all participants. Results 43.3 % of the nursing personnel qualified for the metabolic syndrome diagnostic criteria. 100 % of the nurses working the night shift showed circadian alterations in terms of sleep patterns. Alcohol consumption and high levels of triglycerides were positively and significantly related to insomnia (p ≤ 0.001; p ≤ 0.05). Conclusion The metabolic syndrome is a health problem with a high prevalence in all kinds of nursing personnel. Bodyweight and triglyceride levels were indicators suggesting altered sleep patterns. This situation highlights the importance of designing and implementing strategies aimed at preventing and addressing metabolic syndrome among nursing person nel as a labor health priority.


RESUMO Introdução As alterações metabólicas estão ligadas aos ritmos biológicos, pois esses siste mas controlam aspectos fisiológicos como padrões de sono/vigília, temperatura corporal, pressão arterial e liberação de hormônios endócrinos. Objetivo Identificar a relação entre os componentes da síndrome metabólica e a dissincro nia circadiana na equipe de enfermagem de um hospital público. Métodos Estudo correlacional. Amostra censitária de 30 profissionais de enfermagem com dois turnos. Para a coleta de dados foram utilizados três cartões: a) antecedentes biossociodemográficos e laborais; b) síndrome metabólica; c) ciclo circadiano. No processa mento dos dados foram utilizados os testes Qui-quadrado, R de Pearson e Rho de Spearman, a suposição de normalidade foi verificada com Shapiro-Wilk. Contou-se com a autorização do Comitê de Ética da instituição de saúde e o termo de consentimento informado dos participantes. Resultados 43.3 % da equipe de enfermagem atendeu aos critérios diagnósticos para sín drome metabólica, 100 % do plantão noturno apresentou dissincronia circadiana com base no indicador padrão de sono. O consumo de álcool e o nível elevado de triglicerídeos mos traram relação positiva estatisticamente significativa com a presença de insônia (p ≤ 0.001; p ≤ 0.05). Conclusão A síndrome metabólica é um problema de saúde de alta prevalência entre a equipe de enfermagem, independentemente do nível acadêmico ou turno de trabalho. O peso e os triglicerídeos foram indicadores que mostraram relação com os padrões de sono afetados. Isto ressalta a importância de influenciar a prevenção e o tratamento da síndrome metabólica como prioridade na equipe de enfermagem, desde a saúde do trabalhador.

20.
Evolution ; 75(10): 2371-2387, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34375460

RESUMO

The role of historical factors in establishing patterns of diversity in tropical mountains is of interest to understand the buildup of megadiverse biotas. In these regions, the historical processes of range fragmentation and contraction followed by dispersal are thought to be mediated by the interplay between rugged relief (complex topography) and climate fluctuations and likely explain most of the dynamics of diversification in plants and animals. Although empirical studies addressing the interaction between climate and topography have provided invaluable insights into population divergence and speciation patterns in tropical montane organisms, a more detailed and robust test of such processes in an explicit spatio-temporal framework is still lacking. Consequently, our ability to gain insights into historical range shifts over time and the genomic footprint left by them is limited. Here, we used niche modeling and subgenomic population-level datasets to explore the evolution of two species of warbling finches (genus Microspingus) disjunctly distributed across the Montane Atlantic Forest, a Neotropical region with complex geological and environmental histories. Population structure inferences suggest a scenario of three genetically differentiated populations, which are congruent with both geography and phenotypic variation. Demographic simulations support asynchronous isolation of these populations as recently as ∼40,000 years ago, relatively stable population sizes over recent time, and past gene flow subsequent to divergence. Throughout the last 800,000 years, niche models predicted extensive expansion into lowland areas with increasing overlap of species distributions during glacial periods, with prominent retractions and isolation into higher altitudes during interglacials, which are in line with signs of introgression of currently isolated populations. These results support a dual role of cyclical climatic changes: population divergence and persistence in mountain tops during warm periods followed by periods of expansion and admixture in lower elevations during cold periods. Our results underscore the role of the interplay between landscape and climate as an important mechanism in the evolution of the Neotropical montane biota.


Assuntos
Clima , Passeriformes , Animais , Fluxo Gênico , Variação Genética , Geografia , Filogenia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA