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1.
Sci Total Environ ; 948: 174737, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004365

RESUMO

In recent years, there has been a growing focus on the toxicity and mortality induced by nanoplastics (NPs) in aquatic organisms. However, studies investigating mechanisms underlying oxidative stress (OS), apoptosis, and inflammation induced by NPs in fish remain limited. This study observed that polystyrene NPs (PS-NPs) were accumulated into zebrafish larvae and zebrafish embryonic fibroblast (ZF4 cells), accompanied by the occurrence of pathological damage both at the cellular and tissue-organ level. Additionally, the transcriptional up-regulation of NADPH oxidases (NOXs) and subsequent excessive generation of reactive oxygen species (ROS) resulted in notable changes in the relative mRNA and protein expression levels associated with antioxidant oxidase systems in larvae. Furthermore, the study identified the impact of NPs on mitochondrial ultrastructural, resulting in mitochondrial depolarization and downregulation of mRNA expression related to the electron transport chain due to excessive ROS generation. Short-term exposure to NPs also triggered apoptosis and inflammation in zebrafish larvae, evident from significant up-regulation in mRNA expressions of proapoptotic factors and NF-κB proinflammatory signaling pathway, as well as increased transcription and protein levels of pro-inflammatory factors in larvae. Inhibition of intracellular excessive ROS effectively reduced the induction of apoptosis, NF-κB P65 nuclear migration levels, and cytokine secretion, underscoring OS as a pivotal factor throughout the process of apoptosis and inflammatory responses induced by NPs. This research significantly advances our comprehension of biological effects and underlying mechanisms of NPs in freshwater fish.

2.
Mater Today Bio ; 22: 100753, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37593216

RESUMO

A coordinated interaction between osteogenesis and the osteoimmune microenvironment plays a vital role in regulating bone healing. However, disturbances in the pro- and anti-inflammatory balance hinder the therapeutic advantages of biomaterials. In this study, a novel composite hydrogel was successfully fabricated using graphene oxide (GO)-loaded processed pyritum (PP) in combination with poly(ethylene glycol) diacrylate (PEGDA) and carboxymethyl chitosan (CMC). Subsequently, the immunomodulatory effects and bone regenerative potential of PP/GO@PEGDA/CMC were investigated. The results demonstrated that the PP/GO@PEGDA/CMC hydrogel possessed excellent mechanical properties, swelling capacity, and stability. Moreover, PP/GO@PEGDA/CMC prominently promoted M2 polarization and increased the levels of anti-inflammatory factors (interleukin (IL)-4, IL-10, and transforming growth factor-ß). These beneficial effects facilitated the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells in vitro. Additionally, the in vivo results further verified that the implantation of PP/GO@PEGDA/CMC markedly reduced local inflammation while enhancing bone regeneration at 8 weeks post-implantation. Therefore, the results of this study provide potential therapeutic strategies for bone tissue repair and regeneration by modulating the immune microenvironment.

3.
Sci Total Environ ; 895: 164939, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37348719

RESUMO

Exploring the carbon sequestration capacity of water ecosystems would contribute to coping with climate change. This study conducted an integrated method framework to achieve an improved understanding of the relationship between carbon sequestration and lake ecosystem components, as well as provide a new perspective on climate change for policymakers. The vertically generalized production model revealed the carbon sequestration capacity of lakes. The hierarchical linear model identified the cross-scale factors affecting phytoplankton. Then a developed multi-agents-based model with scenario analysis provided adaptive management strategies for carbon sequestration. Furthermore, we applied the integrated framework in the 63 polluted lakes of Wuhan. The results showed that the average carbon sequestration per unit area was at 0.87 kgC·m-2·a-1, which was greater than that of the ocean and forest ecosystems, indicating that the lakes had a potential capacity for carbon sequestration. Total phosphorus had the strongest effect on the Chl-a (chlorophyll a) concentration (fixed effect (γ) =6.82, P < 0.1), followed by total nitrogen (γ = 6.38, P < 0.05), Rotifer biomass (γ = 1.95, P < 0.01) and water temperature (γ = 1.27, P < 0.05). These results indicated that the bottom-up effect of chemical factors on phytoplankton was greater than the top-down effect of zooplankton. The proportion of grassland at the whole-lakes level would have a negative synergistic impact on the Chl-a with changing the micro water temperature at the part-lakes level (γ = -46.64, P < 0.05). There was no significant interaction effect between land cover change and total nitrogen (phosphorus) on the Chl-a. Therefore, we could indirectly confirm that point source pollution emissions would synergistically affect the Chl-a and carbon sequestration along with the effects of physical-chemical conditions. The coordinated proportional control of nitrogen and phosphorus and the artificial controlling biomass of zooplankton-feeding fish were proposed to improve carbon sequestration and water quality for lake management.


Assuntos
Ecossistema , Lagos , Animais , Lagos/análise , Clorofila A , Sequestro de Carbono , Mudança Climática , Fitoplâncton , Zooplâncton , Fósforo/análise , Nitrogênio/análise , Carbono
4.
PLoS One ; 18(4): e0284186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37043522

RESUMO

To exploretheeffects of physical, mechanical, anti-deterioration properties of graphene oxide (GO) on cement-based cementitious materials, GO sheet dispersions areprepared by the improved Hummers method and ultrasonic dispersion method. The influence of theGO content on the compressive and flexural strengths of cement paste is investigated, and the penetration process of chloride ions in graphene oxide concrete is discussed by the electric accelerated erosion method. Combined with the rapid freeze-thaw test, the deterioration of graphene oxide concrete ismethodically analyzed. Theobtained results reveal that an appropriate amount of GO improves both the compressive and flexural strengths of cement pastev. In the chloride environment, the chloride diffusion coefficient of 0.03% GO concrete is 18.75% less than that of ordinary concrete.Under the action of freeze-thaw cycles, with the increase of salt freezing times, the deterioration mode of GO concrete is a combination of mortar shedding, micro-crack expansion, denudation, and block shedding; The stress-strain curve of the specimen tends to be flat with the growth of salt freezing times. The peak stress gradually lessens, the peak strain gradually grows, and the elastic modulus remarkably reduces. Compared with ordinary cement paste, theGO is capable of promoting the growth of cement paste hydration crystals, changing the size and shape of crystals, and realizingthe regulation of cement paste microstructure. Incorporating an appropriate amount of theGO could promote the cement hydration process and enhance the chemical water-binding amount in the cement paste. The optimal GO content is reported to be 0.03% of the cement mass.


Assuntos
Cloretos , Compressão de Dados , Cloreto de Sódio , Cimentos Ósseos , Cimentos de Ionômeros de Vidro , Halogênios
5.
Math Biosci Eng ; 19(11): 10741-10761, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-36124568

RESUMO

In this paper, considering that sometimes signal transmission may be interrupted, or signal input errors may occur, we establish a novel class of parametric uncertainty hybrid control system models including the impulsive control signals under saturated inputs, which can reflect the signal transmission process more realistically. Based on the step-function method, improved polytopic representation approach and Schur complement, we find the stability conditions, which are less conservative than those with the traditional Lyapunov method, of the considered control system. In addition, we investigate the design of the control gains and the auxiliary control gains for easily finding the suitable control signals, the auxiliary signals and the estimation of the attraction domain. Moreover, our proposed methods are applied to the fixed time impulse problems of uncertain systems with or without Zeno behavior. Simulation results for the uncertain neural network systems are presented to show the feasibility and effectiveness of our stabilization methods using the step-function.

6.
BMC Nurs ; 21(1): 217, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35932073

RESUMO

BACKGROUND: International guidelines advocate providing prompt structured education to individuals with diabetes at diagnosis. However, among the few eligible structured education programs, heterogeneous intervention regimens and inconsistent findings were reported. Eligible programs for Chinese individuals with diabetes are lacking. This study aimed to investigate the effects of a nurse-led integrative medicine-based structured education program on self-management behaviors, glycemic control and self-efficacy among individuals with newly diagnosed type 2 diabetes. METHODS: Employing a randomized controlled trial, 128 individuals with type 2 diabetes diagnosed in the preceding three to nine months were recruited from four university-affiliated tertiary hospitals in Xi'an City, Northwest China, and randomly allocated to the intervention or control groups after baseline assessments. Participants in the intervention group received a 4-week nurse-led integrative medicine-based structured education program, which is theoretically based on the Health Belief Model and Self-Efficacy Theory, in line with updated diabetes management guidelines, and informed by relevant systematic reviews. Participants in the control group received routine care. Self-management behaviors and self-efficacy were measured with the Summary of Diabetes Self-Care Activities and the Diabetes Management Self-Efficacy Scale at baseline, immediate post-intervention and 12 weeks following the intervention while Glycated Hemoglobin A was measured at baseline and the 12th-week follow-up. The intervention effects were estimated using the generalized estimating equation models. RESULTS: Participants in the intervention group exhibited significantly better self-management performance in specific diet regarding intake of fruits and vegetables at both follow-ups (ß = 1.02, p = 0.011 and ß = 0.98, p = 0.016, respectively), specific diet regarding intake of high-fat foods at the immediate post-intervention follow-up (ß = 0.83, p = 0.023), blood glucose monitoring at the 12th-week follow-up (ß = 0.64, p = 0.004), foot care at both follow-ups (ß = 1.80, p <  0.001 and ß = 2.02, p <  0.001, respectively), and medication management at both follow-ups (ß = 0.83, p = 0.005 and ß = 0.95, p = 0.003, respectively). The intervention also introduced significant improvements in Glycated Hemoglobin A (ß = - 0.32%, p <  0.001), and self-efficacy at both follow-ups (ß = 8.73, p <  0.001 and ß = 9.71, p <  0.001, respectively). CONCLUSIONS: The nurse-led integrative medicine-based structured education program could produce beneficial effects on multiple diabetes self-management behaviors, glycemic control and self-efficacy. TRIAL REGISTRATION: This study was retrospectively registered in the ClinicalTrials.gov . on 25/08/2017; registration number: NCT03261895 .

7.
Sci Data ; 9(1): 276, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672328

RESUMO

While there is growing global concern about the impact of antibiotic residues on emergence and enhancement bacteria's resistance, toxicity to natural organisms, and, ultimately, public health, a concise picture of measured environmental concentrations of antibiotic occurrence in multiple environmental matrices, particularly in solid matrices (e.g., sludge, soil, and sediments) is still elusive, especially for China. In this paper, we present an up-to-date dataset of the distribution of antibiotic occurrence in solid environmental matrices in China, derived from 210 peer-reviewed literature published between 2000 and 2020. We extracted geographical sampling locations and measured concentration associated with antibiotic occurrence reported in English and Chinese original publications, and applied quality-control procedures to remove duplicates and ensure accuracy. The dataset contains 6929 records of geo-referenced occurrences for 135 antibiotics distributed over 391 locations distinguished at four levels of scale i.e., provincial, prefectural, county, and township or finer. The geographical dataset provides an updated map of antibiotic occurrence in solid environmental matrices in China and can be used for further environmental health risk assessment.


Assuntos
Antibacterianos , Solo , China , Monitoramento Ambiental
8.
ISA Trans ; 130: 316-324, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35537873

RESUMO

In many actual discontinuous control systems, the state might undergo some abrupt changes when the impulsive effects appear and the impulsive effect will stay active for a period of time which cannot be ignored. Obviously, the traditional instantaneous impulsive system models cannot describe the above process. Then in this paper, considering the actuator saturation and non-instantaneous impulse existing in the real environment, we formulate the new models to describe the nonlinear intermittent control system subject to actuator saturation with non-instantaneous impulsive effects occurring at the moments of system switching. Some exponential stability criteria of this considered intermittent control systems in the form of matrix inequalities are first put forward. Meanwhile, some LMI optimization problems are also proposed to design the control gain for estimating the attraction domain with a fixed decay rate. Finally, simulation results demonstrate the feasibility of the obtained theoretical results.

9.
J Healthc Eng ; 2022: 1499927, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432822

RESUMO

To evaluate the application effect of the 360° safe indwelling infusion program of peripheral venous indwelling needle in the infusion room of pediatric outpatient clinic. A total of 1,000 children who received indwelling needle infusion were randomly divided into experimental group (n = 500; 360° safe indwelling needle) and control group (n = 500; a routine indwelling needle). The incidence of indwelling needle-related complications and adverse events in the experimental group was significantly lower than that in the control group, and the number of indwelling days, indwelling needle usage rate, and parent satisfaction were significantly higher than those in the control group. The 360° safe indwelling infusion program can significantly reduce the incidence of complications and adverse events, and improve the quality of the indwelling needle infusion. The 360° safe indwelling infusion can effectively improve the comprehensive quality and safety of nursing care in the outpatient infusion room.


Assuntos
Instituições de Assistência Ambulatorial , Agulhas , Criança , Humanos
10.
Fish Physiol Biochem ; 48(1): 161-171, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35039993

RESUMO

A study was conducted to evaluate the gonad differentiation of juvenile yellow perch (YP, Perca flavencens) and determine the latest labile period related to hormone treatment. Juvenile fish were subjected to two dietary concentrations of methyltestosterone (MT; 20 and 50 mg/kg feed) for 60 days in three (3) age groups of 38-, 46-, and 67-days post-hatching (dph), where control group were fed with standard commercial feed. Following a 10-month on-growing period, sex phenotypes were determined by gross and histological gonad morphology. Results showed the juvenile YP responded to the exogenous hormone when it was applied at 38 dph for both 20 and 50 mg/kg feed resulting in 100% males. At 46 dph, only 50 mg/kg feed resulted in 100% males. Both MT-treated at 38 and 46 dph significantly differed (P < 0.01) from the expected normal population of male:female (1:1). MT-treated at 67 dph resulted in 37% and 25% intersex fish for both 20 and 50 mg/kg feed dosage groups, respectively. MT-treated at 38 and 46 dph promoted growth and showed significantly heavier mean body weight (P < 0.05) compared to control. The gonadosomatic index (GSI) of MT-treated at 38 and 46 dph was significantly lower than that in control. This study provides the first evidence that juvenile YP can be successfully masculinized when the treatment is initiated at the age of up to 46 dph. The result is important for sex control in aquaculture.


Assuntos
Metiltestosterona , Percas , Diferenciação Sexual , Animais , Feminino , Gônadas , Masculino , Metiltestosterona/farmacologia , Percas/crescimento & desenvolvimento
11.
Int J Parasitol ; 51(9): 749-759, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33798559

RESUMO

Ticks are known as vectors of several pathogens causing various human and animal diseases including Lyme borreliosis, tick-borne encephalitis, and Crimean-Congo hemorrhagic fever. While China is known to have more than 100 tick species well distributed over the country, our knowledge on the likely distribution of ticks in the future remains very limited, which hinders the prevention and control of the risk of tick-borne diseases. In this study, we selected four representative tick species which have different regional distribution foci in mainland China. i.e., Dermacentor marginatus, Dermacentor silvarum, Haemaphysalis longicornis and Ixodes granulatus. We used the MaxEnt model to identify the key environmental factors of tick occurrence and map their potential distributions in 2050 under four combined climate and socioeconomic scenarios (i.e., SSP1-RCP2.6, SSP2-RCP4.5, SSP3-RCP7.0 and SSP5-RCP8.5). We found that the extent of the urban fabric, cropland and forest, temperature annual range and precipitation of the driest month were the main determinants of the potential distributions of the four tick species. Under the combined scenarios, with climate warming, the potential distributions of ticks shifted to further north in China. Due to a decrease in the extent of forest, the distribution probability of ticks declined in central and southern China. In contrast with previous findings on an estimated amplification of tick distribution probability under the extreme emission scenario (RCP8.5), our studies projected an overall reduction in the distribution probability under RCP8.5, owing to an expected effect of land use. Our results could provide new data to help identify the emerging risk areas, with amplifying suitability for tick occurrence, for the prevention and control of tick-borne zoonoses in mainland China. Future directions are suggested towards improved quantity and quality of the tick occurrence database, comprehensiveness of factors and integration of different modelling approaches, and capability to model pathogen spillover at the human-tick interface.


Assuntos
Encefalite Transmitida por Carrapatos , Ixodes , Doença de Lyme , Doenças Transmitidas por Carrapatos , Animais , China/epidemiologia , Mudança Climática , Humanos , Doenças Transmitidas por Carrapatos/epidemiologia
12.
Carbohydr Polym ; 256: 117575, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33483070

RESUMO

Chitosan-modified zinc hydroxystannate (ZHS-CS) was synthesized using the cations of the biomaterial chitosan (CS) and ion replacement strategy. A ZHS-CS and reduced graphene oxide (rGO) hybrid flame retardant (ZHS-CS/rGO) was synthesized for use in flexible poly (vinyl chloride) (PVC). Scanning electron microscopy images indicated that ZHS-CS and rGO were evenly dispersed in ZHS-CS/rGO without agglomeration. Fourier transform infrared spectroscopy results showed that rGO was fully reduced. The flame-retardant and mechanical properties of PVC composites were investigated using the limiting oxygen index (LOI), a cone calorimeter, and mechanical equipment. By replacing one-fifth of the zinc ions in ZHS by chitosan cations to obtain Sn-4Zn-1CS/rGO, the ZHS-CS/rGO was found to improve PVC composite performance. The total heat release and total smoke release of PVC/Sn-4Zn-1CS/rGO were reduced by 24.2 and 40.0 %, respectively, from those of pure PVC.


Assuntos
Quitosana/química , Grafite/síntese química , Cloreto de Polivinila/química , Compostos de Estanho/química , Zinco/química , Materiais Biocompatíveis/química , Retardadores de Chama , Grafite/química , Microscopia Eletrônica de Varredura , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração , Compostos de Zinco , Óxido de Zinco
13.
Pharmazie ; 75(11): 590-594, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33239135

RESUMO

Objective: Several studies have suggested an involvement of the immune system in the occurrence and development of chronic obstructive pulmonary disease (COPD), but the mechanism is still unclear. The aim of this study was to explore the mechanism of ginsenoside in inhibiting inflammation by regulating FOXP3 in COPD. Methods: Eighty COPD patients were selected and 35 healthy people were enrolled in the study to determine clinical efficacy, observation index, and SGRQ scores. Percentage of Treg and Th17 cells were detected by flow cytometry; HE staining was used to detect the effect of ginsenoside therapy on pathological changes of COPD in mice. Additionally, we transfected FOXP3 inhibitor; RT-PCR and western blot were used to detect the inflammation related genes and proteins. Results: The basic information of the patients were comparable. The clinical outcome in the treatment group was better than that in the control group, which indicated that ginsenoside has a certain therapeutic effect on COPD patients. The lung function and 6MWT distance results indicated that ginsenoside could stabilize the clinical symptoms of COPD patients and improve their quality of life. Flow cytometry results showed that ginsenoside can increase Treg expression while reducing Th17 cell expression. RT-PCR and western blot results showed that the expression of TNF-α and IL-17 in the model group was significantly increased after treatment, obviously caused by an increased expression of FOXP3. Conclusion: Ginsenoside can inhibit inflammation in COPD by up-regulating FOXP3.


Assuntos
Anti-Inflamatórios/farmacologia , Ginsenosídeos/farmacologia , Inflamação/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Estudos de Casos e Controles , Feminino , Fatores de Transcrição Forkhead/genética , Ginsenosídeos/administração & dosagem , Humanos , Inflamação/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Qualidade de Vida , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-32708816

RESUMO

Ticks are known as the vectors of various zoonotic diseases such as Lyme borreliosis and tick-borne encephalitis. Though their occurrences are increasingly reported in some parts of China, our understanding of the pattern and determinants of ticks' potential distribution over the country remain limited. In this study, we took advantage of the recently compiled spatial dataset of distribution and diversity of ticks in China, analyzed the environmental determinants of ten frequently reported tick species and mapped the spatial distribution of these species over the country using the MaxEnt model. We found that presence of urban fabric, cropland, and forest in a place are key determents of tick occurrence, suggesting ticks were likely inhabited close to where people live. Besides, precipitation in the driest month was found to have a relatively high contribution in mapping tick distribution. The model projected that theses ticks could be widely distributed in the Northwest, Central North, Northeast, and South China. Our results added new evidence on the potential distribution of a variety of major tick species in China and pinpointed areas with a high potential risk of tick bites and tick-borne diseases for raising public health awareness and prevention responses.


Assuntos
Doenças Transmitidas por Carrapatos , Carrapatos , Animais , China/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia
15.
PeerJ ; 8: e8665, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296597

RESUMO

In order to investigate the mechnism of hepatoprotective of N-acetyl-L-tryptophan (L-NAT) against ischemia-reperfusion (I/R) injury, the effects of L-NAT were investigated in hepatic ischemia-reperfusion injury (HIRI) models both in vitro and in vivo, which were made by BRL cells and Sprague-Dawley (SD) rats, respectively. The cell viability of hepatocyte was assessed by cell counting kit-8 (CCK-8) staining. The activation of autophagy was detected by electron microscopy (EM), quantitative real-time PCR (qRT-PCR), Western blotting and immunofluorescence. The activation of mitophagy was determined by the change of autophagy related protein, change of mitochondrial structure and function, co-location of autophagy protein and MitoTracker. Results showed that the morphological structures of hepatocytes were changed significantly after HIRI, and the cell viability of hydrogen peroxide (H2O2)-induced BRL cells was decreased. Autophagy markers Beclin1, microtubule associated protein 1 light chain 3-II (LC3-II) and autophagy related protein-7 (ATG-7) were highly expressed and the expression of SQSTM1 (P62) was decreased after HIRI, which suggested that autophagy of hepatocytes was activated after I/R. The reduction of ATP, mitochondrial DNA (mtDNA) and the mitochondrial transmembrane potential (ΔΨm) after H2O2-induced revealed that function of mitochondrial had also undergone significant changes. The increased expression of autophagy protein, destructure of mitochondria and mitochondrial dysfunction, the increased co-location of Beclin1 and MitoTracker induced by H2O2 implied the excessive mitophagy. The expression of the autophagy protein was increased by 3-Methyladenine (3-MA), providing another piece of evidence. Importantly, all changes were restored by L-NAT pretreament. In conclusion, the present findings demonstrate that excessive mitophagy involved in the process of HIRI and L-NAT may protect hepatocytes against HIRI by inhibiting activation of mitophagy and improving the structure and function of mitochondria.

16.
Int J Nanomedicine ; 15: 1101-1115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32110010

RESUMO

BACKGROUND: The clinical use of doxorubicin (DOX) is severely limited due to its cardiotoxicity. Thus, there is a need for prophylactic and treatment strategies against DOX-induced cardiotoxicity. PURPOSE: The purpose of this study was to develop a liquiritigenin-loaded submicron emulsion (Lq-SE) with enhanced oral bioavailability and to explore its efficacy against DOX-induced cardiotoxicity. METHODS: Lq-SE was prepared using high-pressure homogenization and characterized using several analytical techniques. The formulation was optimized by central composite design response surface methodology (CCD-RSM). In vivo pharmacokinetic studies, biochemical analyses, reactive oxygen species (ROS) assays, histopathologic assays, and Western blot analyses were performed. RESULTS: Each Lq-SE droplet had a mean particle size of 221.7 ± 5.80 nm, a polydispersity index (PDI) of 0.106 ± 0.068 and a zeta potential of -28.23 ± 0.42 mV. The area under the curve (AUC) of Lq-SE was 595% higher than that of liquiritigenin (Lq). Lq-SE decreased the release of serum cardiac enzymes and ameliorated histopathological changes in the hearts of DOX-challenged mice. Lq-SE significantly reduced oxidative stress by adjusting the levels of ROS, increasing the activity of antioxidative enzymes and inhibiting the protein expression of NOX4 and NOX2. Furthermore, Lq-SE significantly improved the inflammatory response through the mitogen-activated protein kinase (MAPK)/nuclear factor-κB (NF-κB) signalling pathway and induced cardiomyocyte apoptosis. CONCLUSION: Lq-SE could be used as an effective cardioprotective agent against DOX in chemotherapy to enable better treatment outcomes.


Assuntos
Cardiotoxicidade/prevenção & controle , Doxorrubicina/efeitos adversos , Emulsões/química , Flavanonas/farmacologia , Administração Oral , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Disponibilidade Biológica , Cardiotônicos/farmacologia , Cardiotoxicidade/metabolismo , Emulsões/administração & dosagem , Feminino , Flavanonas/administração & dosagem , Flavanonas/farmacocinética , Coração/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Nus , Miocárdio/metabolismo , Miocárdio/patologia , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
17.
J Environ Manage ; 260: 110140, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090834

RESUMO

While planning and management of urban green space (UGS) remain primarily driven by policymakers and expert knowledge, increasing attention has been paid to the general public's perception of and demand for UGS. This study was conducted to provide price-related outcomes to support UGS-related decision making and achieve an improved understanding of the causal relationships underpinning the residents' willingness-to-pay (WTP) for UGS conservation. An extensive survey with 3000 urban residents from three provincial capital cities in central China (i.e., Wuhan, Changsha and Nanchang) was conducted. We applied structural equation modelling to examine a range of hypothetical causal relationships among residents' perceptions about ecosystem services/disservices provided by UGS, frequency of UGS visits, socioeconomic status (SES) and WTP for the conservation of five different types of UGS. We found that residents had an average WTP of 202.4 CNY or 30.6 USD per year cross UGS types, with the attached green space having the greatest WTP (223.0 CNY or 33.7 USD per year), followed by park (215.4 CNY or 32.6 USD year), square (201.7 CNY or 30.5 USD year), suburban ecological (190.1 CNY or 28.7 USD year) and protective (182.0 CNY or 27.5 USD year) green spaces. Perceptions of UGS's ecosystem services had a positive causal impact on WTP, while perceptions of ecosystem disservices would have a negative impact. The frequency of UGS visits was found to amplify WTP at a limited level. It could further heighten and diminish the perceptions of ecosystem services and disservices. Participants with higher SES typically had greater perceptions of UGS's ecosystem services and WTP. Finally, we found that the structure of the causal relationships on WTP varied between cities, highlighting the importance of considering the fine-level impacts of biophysical environment jointly. Our results could help urban planners to understand better the ways urban green space was perceived and anticipate the likely effects of changing spatial patterns of UGS on the benefits and nuisances experienced by the general public.


Assuntos
Ecossistema , China , Cidades , Inquéritos e Questionários
18.
Sci Total Environ ; 704: 135399, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31836234

RESUMO

China has experienced rapid residential land expansion in both urban and rural areas over the past three decades, causing complex ecological and environmental challenges. Much research attention has been paid on urbanisation, yet little is known about rural development. In this study, we analysed and compared the changes in a selected number of landscape indices describing the spatial patterns of both urban and rural area in the Middle Reaches of the Yangtze River in central China from 2005 to 2015 and explored how these changes could be associated with the development of high-speed rail (HSR) using spatial error models. We found a partial synchronised spatial development pattern between urban and rural areas in central China, with an increasingly fragmented pattern for both urban and rural areas, albeit rural areas were expanded in a less contiguous but more complex and dispersed fashion. The impacts of the provision of HSR services on the region's spatial development were found to be multi-level. It was associated with greater urban expansion and dispersion at the county/district level and amplified rural patch size and complexity at the patch level. The departure frequency of HSR trains and proximity to HSR station were found to have affected the magnitude of the impact of HSR service provision on regional spatial development. Our results shed lights on the spatio-temporal evolution of an ecologically important region, add new evidence into the expanding fields of urban and rural morphological studies in China, and provide valuable decision support information for integrated spatial planning of transportation and land use.

19.
J Cell Biochem ; 121(4): 2802-2810, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31692055

RESUMO

BAX is an important proapoptotic protein of the BCL-2 family, and its stability is essential for the regulation of the mitochondrial apoptotic pathway. A previous study revealed that BAX could undergo degradation through the ubiquitin-proteasome pathway. In this study, we identified two lysine sites, K21 and K123, that were critical ubiquitin-binding sites in BAX. Mutation of these two sites prolonged the half-life of BAX and also affected its proapoptotic ability. Intriguingly, we found that ABT-737, a BCL-2 inhibitor, significantly enhanced TRAIL-induced BAX degradation in HCT116 cells and increased TRAIL-induced apoptosis in the HCT116 only with the BAX K21R/K123R mutant, not other BAX mutants. In addition, overexpression of PARKIN, an E3 ubiquitin ligase targeting BAX, dramatically decreased BAX protein level when only treated with ABT-737 in HCT116 cells. Therefore, we speculated that BAX activation is essential for its ubiquitin-dependent degradation.


Assuntos
Ubiquitina/metabolismo , Proteína X Associada a bcl-2/metabolismo , Apoptose , Sítios de Ligação , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Células HCT116 , Humanos , Lisina/química , Mitocôndrias/metabolismo , Mutação , Nitrofenóis/farmacologia , Fases de Leitura Aberta , Piperazinas/farmacologia , Sulfonamidas/farmacologia , Ubiquitina/química , Ubiquitinação
20.
Aquat Toxicol ; 214: 105257, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31336221

RESUMO

The interactions between nanoparticles (NPs) and metals in aquatic environments may modify the bioavailability and toxicity of metals to organisms. In this study, we investigated the effects of titanium dioxide NPs (n-TiO2) on the bioconcentration, depuration, and neurotoxic effects of lead (Pb) in zebrafish larvae. Transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy showed that Pb2+ was adsorbed by n-TiO2 to form NP-Pb complexes in suspension, and these complexes were observed in larval tissues. The bioconcentration of Pb in larvae along with the depuration rates of Pb were higher in the presence of n-TiO2 compared to when n-TiO2 was absent. Exposure to Pb alone induced the expression of the biomarker metallothionein, downregulated neurodevelopment-related genes, and reduced swimming activity of larvae. However, the addition of n-TiO2 to the exposure solution alleviated these effects. The results suggest that n-TiO2 can act as a carrier of Pb to increase its bioconcentration; however, the formation of NP-Pb complexes likely reduces the amount of free Pb2+, thereby reducing toxicity to larvae.


Assuntos
Chumbo/toxicidade , Nanopartículas/toxicidade , Titânio/toxicidade , Peixe-Zebra/metabolismo , Adsorção , Animais , Comportamento Animal/efeitos dos fármacos , Disponibilidade Biológica , Larva/efeitos dos fármacos , Larva/genética , Larva/ultraestrutura , Locomoção/efeitos dos fármacos , Metalotioneína/metabolismo , Nanopartículas/ultraestrutura , Suspensões , Transcrição Gênica/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética
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