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Fine roots and absorptive roots play key roles in acquiring resources throughout soil profiles and determining plant functions along environmental gradients. Yet, the geographical pattern of carbon allocation in fine roots, particularly in absorptive roots, and their relations with plant sizes and evironment are less understood. We sampled 243 xerophytic shrubs from 63 species distributed along the latitudinal gradient (23°N to 32°N) in dry valleys of southwest China and synthetically measured biomass fractions of plant organs, especially fine roots and absorptive roots (1st to 3rd root order). We identified latitudinal patterns of biomass allocation fractions of organs and their relationships with plant sizes and environmental factors. The latitudinal patterns of both absorptive root and fine-root fractions followed weak unimodal distributions; stem biomass fraction increased with the latitude, while the leaf biomass fraction decreased. The fraction of fine-root biomass had negative relationships with plant height and root depth. The fractions of root, fine root, and absorptive root biomass were largely explained by soil moisture. Furthermore, fraction of fine-root biomass increased in a relatively humid environment. Overall, soil moisture was the most important factor in driving latitudinal patterns of biomass fraction. Our study highlighted that functional redistribution of root system biomass was the critical adaptive strategy along a latitudinal gradient.
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Fine-root architecture is critical feature reflecting root explorative and exploitative strategies for soil resources and soil space occupancy. Yet, studies on the variation of fine-root architecture across different species are scare and little work has been done to integrate the potential drivers on these variations along a biogeographical gradient in arid ecosystems. We measured root branching intensity, topological index, and root branching ratios as well as morphological traits (root diameter and length) in dry valley along a 1000 km latitudinal gradient. Influence of phylogeny, environmental factors on fine-root architecture and trade-offs among root traits were evaluated. With increasing latitude, the topological index and second to third root order branching ratio decreased, whereas first-to-second branching ratio increased. Root branching intensity was associated with short and thin fine roots, but has no significant latitudinal pattern. As a whole, soil microbial biomass was the most important driver in the variation of root branching intensity, and soil texture was the strongest predictor of topological index. Additionally, mean annual temperature was an important factor influencing first-to-second branching ratio. Our results suggest variations in fine-root architectures were more dependent on environmental variables than phylogeny, signifying that fine-root architecture is sensitive to environmental variations.
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BACKGROUND: Poor sleep quality is associated with multiple factors in cardiac surgery patients. AIM: To examine the trajectory of sleep quality and its associated factors over 3 months in Taiwanese patients undergoing cardiac surgery. STUDY DESIGN: A longitudinal study. This study enrolled 95 patients undergoing cardiac surgery in northern Taiwan. Sleep quality was measured using the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale before surgery, at discharge, and at 1 month and 3 months postsurgery. RESULTS: The majority of participants reported poor sleep quality before cardiac surgery (76.8%) and at discharge (81.6%), and they showed significant improvements in sleep quality at 1 month (B = -0.93, p = .023) and 3 months postsurgery (B = -1.50, p < .001). Significant daytime sleepiness was reported by 25.3% of patients before cardiac surgery, and this proportion significantly decreased at 3 months postsurgery (B = -2.59, p < .001). The significant predictors of sleep quality in cardiac surgery patients were symptom distress, sleep medications, occupation, left ventricular ejection fraction, ACE-I drugs and potassium ions, which explained 53.7% of the total variance in sleep quality. Having a nap habit was an independent predictor of daytime sleepiness in cardiac surgery patients, which could explain 3.7% of the total variation. CONCLUSION: Poor sleep quality was common in patients undergoing cardiac surgery and was associated with multiple factors, including symptom distress, cardiac function, medications, and psychosocial and environmental factors. RELEVANCE TO CLINICAL PRACTICE: Poor sleep quality was observed in cardiac surgical patients before surgery and at discharge postsurgery. Patient education on symptom management, medication adherence and sleep hygiene are suggested to improve sleep quality in patients undergoing cardiac surgery.
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The COVID-19 pandemic outbreak significantly challenged the cities' abilities to recover from shocks, and cities' responses have widely differed. Understanding these disparate responses has been insufficient, especially from a social recovery perspective. In this study, we propose the concept of social recovery and develop a comprehensive perspective on how a city's socioeconomic characteristics affect it. The analytical framework is applied to 296 prefecture-level cities in China, with social recovery measured by the changes in intercity intensity between the pre-pandemic baseline (2019 Q1 and Q2) and the period in which the pandemic slightly abated (2020 Q1 and Q2) through anonymized location-based big data. The results indicate that the social recovery of Chinese cities during the COVID-19 pandemic are significantly spatially correlated. Cities with larger populations, a higher proportion of GDP in the secondary industry, higher road density or more adequate medical resources tend to recover socially better. Moreover, these municipal characteristics have significant spatial spillover effects. Specifically, city size, government intervention and industrial structure show negative spillover effects on neighboring areas while information dissemination efficiency, road density, and the number of community health services per capita have positive spillover. This study fills the knowledge gap regarding the different performances of cities when they face pandemic shocks. The assessment of a city's social recovery is an insight into the theoretical framework of vulnerability that aids in translating it into urban resilience. Hence our findings provide practice implications for China and beyond as the interest in urban-resilience development surges around the post-pandemic world.
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New nanocarrier technologies are emerging, and they have great potential for improving drug delivery, targeting efficiency and bioavailability. Virus-like particles (VLPs) are natural nanoparticles from animal and plant viruses and bacteriophages. Hence, VLPs present several great advantages, such as morphological uniformity, biocompatibility, reduced toxicity and easy functionalisation. VLPs can deliver many active ingredients to the target tissue and have great potential as a nanocarrier to overcome the limitations associated with other nanoparticles. This review will focus primarily on the construction and applications of VLPs, particularly as a novel nanocarrier to deliver active ingredients. Herein, the main methods for the construction, purification and characterisation of VLPs, as well as various VLP-based materials used in delivery systems are summarised. The biological distribution of VLPs in drug delivery, phagocyte-mediated clearance and toxicity are also discussed.
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Bacteriófagos , Nanopartículas , Animais , Sistemas de Liberação de Medicamentos/métodosRESUMO
BACKGROUND: Fatigue is associated with multidimensional factors in heart failure patients. Investigating longitudinal changes in fatigue and its association in patients undergoing cardiac surgery is needed to create interventions for improving fatigue during recovery. AIMS: This study examined the trajectory of fatigue and its associated factors over time in patients undergoing cardiac surgery. METHODS: This longitudinal study enrolled 125 patients undergoing cardiac surgery in northern Taiwan. Patients completed questionnaires before surgery, at discharge, and at 1, 3 and 6 months post-discharge. Fatigue was measured using the General Fatigue Scale. Generalised estimating equation models were fitted to identify variables associated with fatigue over time. This study complied with the STROBE checklist. RESULTS: The sample (mean age = 60.70 ± 10.42) was mostly male (68%). High fatigue was found in 73.6% of patients before cardiac surgery and significantly decreased over the six months after discharge. NYHA III/IV, lower haemoglobin level, more symptom distress, poor sleep quality, higher anxiety and depression and lower social and family support were significantly associated with an increase in fatigue levels over time. Compared with before discharge, decreases in sleep quality at 1, 3 and 6 months were significantly associated with an increase in fatigue levels (p < .001). The increases in social support (B = 0.20, p = .016) and family support (B = 0.37, p = .002) at 6 months were significantly associated with an increase in the fatigue scores. CONCLUSION: Fatigue was common and associated with symptoms, sleep quality, emotion and social support in patients undergoing cardiac surgery. In addition to symptom management, improving sleep quality and social support are important to manage fatigue for the long-term care of patients undergoing cardiac surgery. RELEVANCE TO CLINICAL PRACTICE: Patient education on symptom management, sleep hygiene and family support is suggested to improve fatigue in patients recovering from cardiac surgery.
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Assistência ao Convalescente , Procedimentos Cirúrgicos Cardíacos , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Longitudinais , Alta do Paciente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Depressão , Fadiga/etiologia , Inquéritos e Questionários , Qualidade de VidaRESUMO
Liposomes are among the most extensively applied drug carriers due to their excellent biocompatibility, controllable size and ease of modification. In the present study, we prepared untargeted liposomes (LP) and targeting liposomes modified with Arg-Gly-Asp (RGD-LP), and Doxorubicin Hydrochloride (DOX) or fluorescent probe was loaded. RGD-LP/DOX was identified to be uniformly spherical in size 131.2 ± 2.7 nm. Based on flow cytometry analysis and the confocal laser scanning microscopy, RGD-LP had a higher uptake into HRT-18 colorectal cancer cells than LP. Further, in vivo imaging study further suggested that RGD-LP could significantly increase the liposome accumulation in the tumour tissues of the mice bearing subcutaneous tumours. By investigating the targeting mechanism of RGD-LP, we found that they entered the cell via macropinocytosis. When loaded with DOX, RGD-LP exerted stronger tumour growth inhibitory activity against tumours of colorectal carcinoma compared to LP. Moreover, RGD-LP induced autophagy. Therefore, RGD-LP have the potential to be applied as a targeted colorectal carcinoma therapy.
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Autofagia/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Lipossomos/administração & dosagem , Oligopeptídeos/administração & dosagem , Animais , Linhagem Celular Tumoral , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Camundongos , Camundongos NusRESUMO
OBJECTIVE: We investigated the variation in dimensionality (D2) of neuromagnetic activity over the primary sensorimotor cortex (SM1) in healthy adults performing motor tasks of different difficulty. METHODS: Magnetoencephalography (MEG) was used to record neuromagnetic activity during self-paced, brisk unimanual finger extension at a rate of 1 and 2 Hz using the index finger of the dominant and non-dominant hands in 16 healthy subjects. Motor task difficulty was rated by the relative difference in time measurement between 1 and 2 Hz finger movements of both hands. The relative difference in dimensionality of SM1 activity was calculated by subtracting the D2 value in 2 Hz movement from that in 1 Hz one within subjects. RESULTS: Simple regression analyses show a significantly negative relationship between the relative dimensional complexity and the relative motor task difficulty in the contralateral SM1 for the left- (p<0.05), but not the right- (p=0.447) hand movement. CONCLUSIONS: The present data suggest that a motor task of greater difficulty may engender a reduction of simultaneously active quasi-independent neuronal generators in the contralateral SM1 underpinned by stronger neuronal connectivity of a relatively low dimensionality. SIGNIFICANCE: The decrease in dimensional complexity of MEG activity associated with a motor task of greater difficulty gives new insights to motor control strategy.