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1.
J Environ Manage ; 302(Pt B): 114130, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34801868

RESUMO

Although soil fungi play a pivotal role in determining soil ecosystematic feedbacks to afforestation, there remains a big knowledge gap in the effects of afforestation on soil fungal communities, especially at a watershed scale. In this study, the variations of soil fungal diversity and community structures under afforestation were investigated in Nanliu River Basin, where paddy field and dry farmland were converted to eucalyptus plantation at an unprecedented speed. Spatial distance along the upper, middle and lower reaches of the Basin were also considered to analyze the dominant sources of the variations. The results demonstrated that eucalyptus afforestation had little effect on soil fungal diversity but could significantly influence fungal community structures. As paddy field and dry farmland converted to eucalyptus plantation, dominant fungal phylum shifted from Ascomycota to Ascomycota and Basidiomycota. Compared with afforestation from dry farmland, much bigger variation of fungal community structures was found in afforestation from paddy field. In addition, the significant change of fungal community structures exhibited in the upper reaches was from dry farmland, while presented in the middle reaches was from paddy field. However, afforestation comprised a larger source of variation than spatial distance within the soil fungal community structures, and Fusarium, Westerdykella,Zopfiella and Scleroderma were the most sensitive genera affected by afforestation. These results showed that afforestation did not always cause soil fungal diversity change and the heterogeneity of fungal community structures under afforestation was mainly controlled by original land use practices, while spatial distance partly decided the results.

2.
J Sci Food Agric ; 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312873

RESUMO

BACKGROUND: Astaxanthin (ASTA) is a kind of food-derived active ingredient (FDAI) with antioxidant and antidiabetic functions. It is nontoxic but its poor solubility and low bioavailability hinder its application in the food industry. In this study, a novel carrier, polyethylene glycol-grafted chitosan (PEG-g-CS) was applied to enhance the bioavailability of astaxanthin. It encapsulated astaxanthin completely by solvent evaporation to manufacture astaxanthin using poly (ethylene glycol)-graft-chitosan nanoparticles (ASTA-PEG-g-CS) nanoparticles to improve absorption. RESULTS: The ASTA-PEG-g-CS nanoparticles were spherical, with a particle size below 200 nm and a ζ potential of about -26 mV. Polyethylene glycol-grafted chitosan can encapsulate astaxanthin well, and the encapsulated astaxanthin was released rapidly - in 15 min in an in vitro release study. In a rat single-pass intestinal perfusion study, a low concentration of ASTA-PEG-g-CS nanoparticle (0.2 µg mL-1 ) was better absorbed in the intestine. In particular, the jejunum could absorb most astaxanthin without a change in the concentration. An in vivo release study also demonstrated that ASTA-PEG-g-CS nanoparticles enhanced oral bioavailability significantly. CONCLUSION: This novel carrier, PEG-g-CS, provided a simple way to encapsulate food, which improved the bioavailability of hydrophobic ingredients. © 2021 Society of Chemical Industry.

3.
Pharmacol Res Perspect ; 9(4): e00825, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34310866

RESUMO

Bronchial pneumonia in children is a common infectious disease in toddlers and infants, which may cause hyperpyrexia, pulmonary moist rales, and even respiratory failure. Traditional drugs for bronchial pneumonia in children often lead to drug resistance and side effects. Recently, naringenin has been reported to be a potential treatment for several airway inflammatory diseases due to its anti-inflammatory and anti-microbial activities. The current clinical study aimed to evaluate the safety and therapeutic effect of naringenin in treating bronchial pneumonia in children. A total of 180 eligible patients were randomly assigned into naringenin (NAR) group and azithromycin (AZI) group. All participants were required to follow a 5-day oral administration, and their serum cytokine levels were measured during the clinical intervention. After the treatment, the disappearance time of clinical symptoms, and the incidences of complications and adverse reactions were compared between the two groups. Naringenin was able to inhibit inflammation, shorten the disappearance time of clinical symptoms, reduce the incidences of bronchial pneumonia complications and related adverse reactions, and improve the health conditions of the patients. Our results suggested that naringenin was safe and beneficial to children with bronchial pneumonia, providing new insights into the clinical application of naringenin.

4.
Microbiome ; 9(1): 128, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082826

RESUMO

BACKGROUND: Freshwater salinization may result in significant changes of microbial community composition and diversity, with implications for ecosystem processes and function. Earlier research has revealed the importance of large shifts in salinity on microbial physiology and ecology, whereas studies on the effects of smaller or narrower shifts in salinity on the microeukaryotic community in inland waters are scarce. Our aim was to unveil community assembly mechanisms and the stability of microeukaryotic plankton networks at low shifts in salinity. RESULTS: Here, we analyzed a high-resolution time series of plankton data from an urban reservoir in subtropical China over 13 consecutive months following one periodic salinity change ranging from 0 to 6.1‰. We found that (1) salinity increase altered the community composition and led to a significant decrease of plankton diversity, (2) salinity change influenced microeukaryotic plankton community assembly primarily by regulating the deterministic-stochastic balance, with deterministic processes becoming more important with increased salinity, and (3) core plankton subnetwork robustness was higher at low-salinity levels, while the satellite subnetworks had greater robustness at the medium-/high-salinity levels. Our results suggest that the influence of salinity, rather than successional time, is an important driving force for shaping microeukaryotic plankton community dynamics. CONCLUSIONS: Our findings demonstrate that at low salinities, even small increases in salinity are sufficient to exert a selective pressure to reduce the microeukaryotic plankton diversity and alter community assembly mechanism and network stability. Our results provide new insights into plankton ecology of inland urban waters and the impacts of salinity change in the assembly of microbiotas and network architecture. Video abstract.


Assuntos
Ecossistema , Plâncton , China , Ecologia , Salinidade
5.
FEBS Open Bio ; 11(7): 2041-2049, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34081837

RESUMO

Ring finger protein 6 (RNF6) is implicated in various human malignancies, but its function in cervical cancer (CC) is incompletely understood. Here, we explored the biological significance of RNF6 in HeLa CC cells and the underlying regulatory mechanisms. The expression of RNF6 was observed to be high in both primary tissues and CC cells. RNF6 promoted HeLa CC cell growth. Knockdown of RNF6 in CC cells resulted in suppression of proliferation and promotion of apoptosis. Moreover, elevation of RNF6 had an adverse effect on the prognosis of CC. Subsequent analyses showed that these effects may be mediated via activation of ERK signaling. These findings provide evidence that the knockdown of RNF6 suppresses the MAPK/ERK pathway to regulate the growth of CC cells, which suggests that RNF6 may have potential as a target for diagnosis and treatment for CC.

6.
Mol Ther ; 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34174443

RESUMO

Myosin VI(MYO6) is an unconventional myosin that is vital for auditory and vestibular function. Pathogenic variants in the human MYO6 gene cause autosomal-dominant or -recessive forms of hearing loss. Effective treatments for Myo6 mutation causing hearing loss are limited. We studied whether adeno-associated virus (AAV)-PHP.eB vector-mediated in vivo delivery of Staphylococcus aureus Cas9 (SaCas9-KKH)-single-guide RNA (sgRNA) complexes could ameliorate hearing loss in a Myo6WT/C442Y mouse model that recapitulated the phenotypes of human patients. The in vivo editing efficiency of the AAV-SaCas9-KKH-Myo6-g2 system on Myo6C442Y is 4.05% on average in Myo6WT/C442Y mice, which was ∼17-fold greater than editing efficiency of Myo6WT alleles. Rescue of auditory function was observed up to 5 months post AAV-SaCas9-KKH-Myo6-g2 injection in Myo6WT/C442Y mice. Meanwhile, shorter latencies of auditory brainstem response (ABR) wave I, lower distortion product otoacoustic emission (DPOAE) thresholds, increased cell survival rates, more regular hair bundle morphology, and recovery of inward calcium levels were also observed in the AAV-SaCas9-KKH-Myo6-g2-treated ears compared to untreated ears. These findings provide further reference for in vivo genome editing as a therapeutic treatment for various semi-dominant forms of hearing loss and other semi-dominant diseases.

7.
Environ Pollut ; 285: 117336, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34052609

RESUMO

Biological monitoring and assessment are the first and most fundamental steps towards diagnosing ecological or environmental quality. Increasing anthropogenic impact on urban ecosystems has prompted the development of less expensive and more efficient bioassessment approaches. Generally, a morphospecies based approach is effective for plants and large organisms but challenging for the microbial biosphere. To overcome this challenge, we used high-throughput DNA sequencing for predicting anthropogenic effects on microeukaryotic communities in urban waterbodies along a pollution gradient in Wuhan City, central China in summer 2019. Our results indicated that microeukaryotic community structure was distinct between non-urban polluted reservoir and urban polluted waterbodies. The heterogeneity of environmental condition significantly affected the microeukaryotic diversity, community structure, and species interactions. Integrated co-occurring network analysis revealed that the pollution gradient has a significant adverse impact on network complexity and network dissimilarity. These results revealed that the significant variation in anthropogenically-driven environmental condition shaped microeukaryotic communities in urban freshwater ecosystems. Furthermore, we observed that the relative abundance of indicative OTUs were significantly and negatively correlated with pollution level and these indicative OTUs could be used to predict the water quality status with up to 77% success. Thus, our multiple approaches combining 18S rDNA amplicon sequencing, co-occurring network and indicator species analyses suggest that this study gives a novel approach based on microeukaryotic communities to assess and predict the water quality status of urban aquatic environments.


Assuntos
Código de Barras de DNA Taxonômico , Ecossistema , DNA Ribossômico , Monitoramento Ambiental , Estações do Ano , Qualidade da Água
8.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785593

RESUMO

During vertebrate embryogenesis, fetal hematopoietic stem and progenitor cells (HSPCs) exhibit expansion and differentiation properties in a supportive hematopoietic niche. To profile the developmental landscape of fetal HSPCs and their local niche, here, using single-cell RNA-sequencing, we deciphered a dynamic atlas covering 28,777 cells and 9 major cell types (23 clusters) of zebrafish caudal hematopoietic tissue (CHT). We characterized four heterogeneous HSPCs with distinct lineage priming and metabolic gene signatures. Furthermore, we investigated the regulatory mechanism of CHT niche components for HSPC development, with a focus on the transcription factors and ligand-receptor networks involved in HSPC expansion. Importantly, we identified an endothelial cell-specific G protein-coupled receptor 182, followed by in vivo and in vitro functional validation of its evolutionally conserved role in supporting HSPC expansion in zebrafish and mice. Finally, comparison between zebrafish CHT and human fetal liver highlighted the conservation and divergence across evolution. These findings enhance our understanding of the regulatory mechanism underlying hematopoietic niche for HSPC expansion in vivo and provide insights into improving protocols for HSPC expansion in vitro.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas/fisiologia , Nicho de Células-Tronco , Animais , Linhagem da Célula , Feto/metabolismo , Perfilação da Expressão Gênica , Humanos , Fígado/metabolismo , Camundongos , Análise de Célula Única , Peixe-Zebra
9.
Blood ; 137(2): 190-202, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-32756943

RESUMO

Nascent hematopoietic stem and progenitor cells (HSPCs) acquire definitive hematopoietic characteristics only when they develop into fetal HSPCs; however, the mechanisms underlying fetal HSPC development are poorly understood. Here, we profiled the chromatin accessibility and transcriptional features of zebrafish nascent and fetal HSPCs using ATAC-seq and RNA-seq and revealed dynamic changes during HSPC transition. Functional assays demonstrated that chromatin remodeler-mediated epigenetic programming facilitates fetal HSPC development in vertebrates. Systematical screening of chromatin remodeler-related genes identified that smarca5 is responsible for the maintenance of chromatin accessibility at promoters of hematopoiesis-related genes in fetal HSPCs. Mechanistically, Smarca5 interacts with nucleolin to promote chromatin remodeling, thereby facilitating genomic binding of transcription factors to regulate expression of hematopoietic regulators such as bcl11ab. Our results unravel a new role of epigenetic regulation and reveal that Smarca5-mediated epigenetic programming is responsible for fetal HSPC development, which will provide new insights into the generation of functional HSPCs both in vivo and in vitro.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Epigênese Genética/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Proteínas de Peixe-Zebra/metabolismo , Adenosina Trifosfatases/genética , Animais , Proteínas Cromossômicas não Histona/genética , Camundongos , Camundongos Endogâmicos C57BL , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
10.
Water Res ; 188: 116470, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33045638

RESUMO

Intense storms pose a serious threat to ecosystem functioning and services. However, the effects of typhoons (tropical cyclones) on the biogeochemical processes mediating risk of eutrophication in deep freshwater ecosystems remain unclear. Here, we conducted a three-year study to elucidate linkages between environmental change, stable isotopes and the stoichiometry of particulate organic matter (POM), and nutrient cycling (i.e., carbon, nitrogen and phosphorus) in a subtropical deep reservoir subjected to typhoon events. The typhoons significantly changed the nutrient levels in the deep waters as well as the thermocline position. Increased typhoon-driven organic matter input, algae sinking and heterotrophic decomposition interacted with each other to cause steep and prolonged increases of total nitrogen, ammonium nitrogen and total phosphorus in the bottom waters of the reservoir. Small-sized or pico-sized POM (i.e., 0.2-3 µm) showed a substantial increase in bottom waters, and it exhibited stronger response than large-sized POM (i.e., 3-20, 20-64, 64-200 µm) to the typhoons. Our results also indicated that typhoons boost the nutrient cycling in deep waters mainly through pico-sized POM.


Assuntos
Tempestades Ciclônicas , Ecossistema , Eutrofização , Água Doce , Nitrogênio/análise , Nutrientes , Material Particulado , Papel (figurativo)
11.
Polymers (Basel) ; 12(11)2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33153103

RESUMO

Studies on the influence of drying processes on cellulose nanofiber (CNF) aerogel performance has always been a great challenge. In this study, CNF aerogels were prepared via two different drying techniques. The CNF solution was prepared via existing chemical methods, and the resultant aerogel was fabricated through supercritical CO2 drying and liquid nitrogen freeze-drying techniques. The microstructure, shrinkage, specific surface area, pore volume, density, compression strength, and isothermal desorption curves of CNF aerogel were characterized. The aerogel obtained from the liquid nitrogen freeze-drying method showed a relatively higher shrinkage, higher compression strength, lower specific surface area, higher pore volume, and higher density. The N2 adsorption capacity and pore diameter of the aerogel obtained via the liquid nitrogen freeze-drying method were lower than the aerogel that underwent supercritical CO2 drying. However, the structures of CNF aerogels obtained from these two drying methods were extremely similar.

12.
Huan Jing Ke Xue ; 41(7): 3102-3111, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608882

RESUMO

To explore the variation of mercury in the atmosphere in Suzhou, continuous monitoring of gaseous element mercury (GEM), gaseous oxidized mercury (GOM), and particulate bound mercury (PBM) was conducted from January 1 to December 31, 2018, in Suzhou. The weights trajectory analysis method (CWT) and concentration rose were used to analyze the atmospheric mercury sources and concentration variation. The results showed that during the monitoring period, the concentration ranges of GEM, GOM, and PBM in Suzhou were 0-53.3 ng·m-3, 0-256 pg·m-3, and 0-5208 pg·m-3, respectively. The corresponding annual average concentrations of the three mercury species were (2.57±2.09) ng·m-3, (5.27±15.7) pg·m-3, and (16.0±157) pg·m-3, respectively. GEM was the main component of atmospheric mercury in Suzhou. During the monitoring period, the average concentration of GEM in Suzhou was highest in winter, higher in spring than in autumn, and lowest in summer. According to the CWT, the mercury-containing air mass in spring and winter predominantly originated from inland; in summer, it mainly originated from the local area, the Yellow Sea, and the East China Sea, and in autumn from inland, the Yellow Sea, and the Bohai Sea. The wind and mercury rose charts showed that atmospheric mercury concentrations were higher from inland and lower from the ocean. During the monitoring period, the average concentrations of GEM and PBM in Suzhou were lower during the day than the night. The diurnal variation of GEM and PBM was significantly and strongly correlated with solar radiation, humidity, and air temperature. The average concentration of GOM showed multiple peaks and valleys in one day. Some peaks were caused by fuel oil combustion emissions, and some by O3 oxidation with GEM.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 235: 118306, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32247256

RESUMO

A new method based on fluorescence spectroscopy for the sensitive determination of aminophylline (AP), an antiasthmatic drug, was developed in this work. Amino-functionalized graphene quantum dots (afGQDs) were synthesized based on a two-step method and they were characterized by transmission electron microscope, UV-vis absorption spectrum and infrared spectrum. The fluorescence of afGQDs was quenched by riboflavin (Rf) via both dynamic quenching and inner filter effect. Photoilluminated Rf-AP system in the presence of oxygen produced hydroxyl radicals (OH). The latter accepted electrons from afGQDs owing to a photo-induced electron transfer process and led to the further fluorescence decline. The changing extent of the fluorescence intensity was found to be proportional to the concentration of AP in the range of 0.10-10 µg mL-1 and the limit of detection arrived at 40 ng mL-1. The proposed method was successfully employed for the determination of AP in a pharmaceutical sample and the recovery rate varied in the range of 99%-106%.


Assuntos
Aminofilina/análise , Grafite/química , Pontos Quânticos , Riboflavina/química , Ácido Cítrico/química , Concentração de Íons de Hidrogênio , Radical Hidroxila , Microscopia Eletrônica de Transmissão , Fotoquímica/métodos , Pirólise , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
14.
ACS Appl Mater Interfaces ; 12(12): 14064-14070, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32125818

RESUMO

One-dimensionally (1D) hollow noble meal nanotubes are attracting continuous attention because of their huge potential applications in catalysis and electrocatalysis. Herein, we successfully synthesize hollow iridium nanotubes (Ir NTs) with the rough porous surface by the 1-hydroxyethylidene-1, 1-diphosphonic acid-induced self-template method under hydrothermal conditions and investigate their electrocatalytic performance for oxygen evolution (OER) and nitrate reduction reactions (NO3-RR) in an acidic electrolyte. The unique 1D and porous structure endow Ir NTs with big surface areas, high conductivity, and optimal atom utilization efficiency. Consequently, Ir NTs exhibit significantly enhanced activity and durability for acidic OERs compared with commercial Ir nanocrystals (Ir c-NCs), which only require the overpotential of 245 mV to deliver the current density of 10 mA cm-2. Meanwhile, Ir NTs also show higher electrocatalytic activity for NO3-RR than that of Ir c-NCs, such as a Faraday efficiency of 84.7% and yield rate of 921 µg h-1 mgcat-1 for ammonia generation, suggesting that Ir NTs are universally advanced Ir-based electrocatalysts.

15.
Mikrochim Acta ; 187(4): 210, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152671

RESUMO

A one-pot method based on cyclic voltammetric scan was used to fabricate a glassy carbon electrode modified with nanocomposites consisting of poly(thionine) and amino-functionalized graphene quantum dots (afGQDs). Under near-neutral conditions, the dye polymer was effectively oxidized by hydroxyl radicals (·OH) that were derived from the copper-catalyzed Fenton-like reaction, and the cathodic peak current on the modified electrode greatly increased. The reaction of Cu2+ with thiourea (TU) and the generation of a complex, CuTU2+, led to the decrease of Cu2+/Cu+ species, which inhibited the Fenton-like reaction and reduced the electrochemical response change. Due to a displacement reaction, the addition of Hg2+ into the H2O2-Cu2+-TU system resulted in the release of cuprous ions that benefited the Fenton-like reaction. Under the following optimal conditions: 6 mg mL-1 afGQDs and the 25-cycle potential cycling for the fabrication of the modified electrode, pH 6.5, and the [Formula: see text] ratio of 1.0, the increasing extent of the cathodic peak current exhibited a good linear response to the logarithm of the Hg2+ concentration in the range of 1 pM-1 µM with a detection limit of 0.6 pM. Mercury ions in a water sample were determined with good recovery, ranging from 97 to 103%. The investigation on the uptake of Hg2+ into human vascular endothelial cells, HUVEC, shows that the cells incubated in the high-concentration glucose medium absorbed more mercury ions than HUVEC incubated in the normal medium. As a result, Hg2+ could lead to the greater damage to the former. Graphical abstract.

16.
Front Microbiol ; 11: 118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117142

RESUMO

Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has evolved signal transduction systems to control the expression of virulence determinants. It was previously shown that two cysteine residues in the periplasmic domain of TcpP are important for TcpP dimerization and activation of virulence gene expression by responding to environmental signals in the small intestine such as bile salts. In the cytoplasmic domain of TcpP, there are another four cysteine residues, C19, C51, C58, and C124. In this study, the functions of these four cysteine residues were investigated and we found that only C58 is essential for TcpP dimerization and for activating virulence gene expression. To better characterize this cysteine residue, site-directed mutagenesis was performed to assess the effects on TcpP homodimerization and virulence gene activation. A TcpPC 58 S mutant was unable to form homodimers and activate virulence gene expression, and did not colonize infant mice. However, a TcpPC 19 / 51 / 124 S mutant was not attenuated for virulence. These results suggest that C58 of TcpP is indispensable for TcpP function and is essential for V. cholerae virulence factor production and pathogenesis.

17.
J Fluoresc ; 30(2): 301-308, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32002726

RESUMO

Copper is an important trace element involved in several physiological processes. The deficiency or excess of Cu in the human body may cause some serious diseases. EDTA has been widely employed in many industry fields owing to its excellent chelating ability. The poor biodegradability of EDTA makes itself a persistent substance in the natural environment. This work provided a fluorescence "on-off-on" strategy for the sequential determination of trace Cu2+ and EDTA. Amino-functionalized graphene quantum dots (afGQDs) were synthetized via the thermal pyrolysis of citric acid. Fluorescence resonance energy transfer (FRET) between afGQDs and 1-(2-pyridylazo)-2-naphthol (PAN) effectively quenched the fluorescence of this carbon-based nanomaterial. The generation of the Cu2+-PAN complex caused the increased FRET efficiency and the further fluorescence decline. The change of the fluorescence intensity sensitively responded to copper ions. The linear range and the limit of detection (LOD) were 1 nM-10 µM and 0.87 nM, respectively. EDTA could decompose the Cu2+-PAN complex and liberate PAN, which weakened the FRET efficiency and led to the fluorescence recovery. The increasing degree of the fluorescence intensity was closely related to EDTA within a concentration range from 10 nM to 10 µM with a LOD at 4 nM. Copper ions in the water and human serum samples and EDTA in the trypsin-EDTA sample were successfully detected based on the proposed fluorescence method.


Assuntos
Cobre/análise , Ácido Edético/análise , Corantes Fluorescentes/química , Grafite/química , Pontos Quânticos/química , Fluorescência , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Íons/análise , Estrutura Molecular , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície
18.
Polymers (Basel) ; 11(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817674

RESUMO

As one of the main consumables of interior decoration and furniture, decorative paper can be seen everywhere in the indoor space. However, because of its high content of formaldehyde, it has a certain threat to people's health. Therefore, it is necessary to develop and study new formaldehyde-free decorative paper to meet the market demand. In this work, we have obtained formaldehyde-free decorative paper with high CO2 adsorption capacity. Here, cellulose nanocrystals (CNC) were prepared by hydrolyzing microcrystalline cellulose with sulfuric acid. The N-(2-aminoethyl) (3-amino-propyl) methyldimethoxysilane (AEAPMDS) was grafted onto the CNCs by liquid phase hydrothermal treatment, and the aqueous solution was substituted by tert-butanol to obtain aminated CNCs (AEAPMDS-CNCs). The as-prepared AEAPMDS-CNCs were applied to formaldehyde-free decorative paper by the spin-coating method. The effects of various parameters on the properties of synthetic materials were systematically studied, and the optimum reaction conditions were revealed. Moreover, the surface bond strength and abrasion resistance of modified formaldehyde-free decorative paper were investigated. The experimental results showed that AEAPMDS grafted successfully without destroying the basic morphology of the CNCs. The formaldehyde-free decorative paper coated with AEAPMDS-CNCs had high CO2 adsorption capacity and exhibited excellent performance of veneer to plywood. Therefore, laminating the prepared formaldehyde-free decorative paper onto indoor furniture can achieve the purpose of capturing indoor CO2 and have a highly potential use for the indoor decoration.

20.
J Chem Neuroanat ; 102: 101687, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31562918

RESUMO

Perinatal hypoxic-ischemia (HI) is a leading cause of acute mortality and neurologic complications in newborns. Geniposide, a natural product extracted from the herb Gardenia jasminoides, has been shown to possess neuroprotective effects in neurologic deficits. This study aims to investigate whether Geniposide has therapeutic potential to HI brain injury and the underlying mechanisms. C57/bl6 mice were subjected to HI insult on postnatal day 10. Geniposide (20 mg/kg b.w.) was administered intragastrically every day after HI insult for 7 successional days. Then mice at P18 were sacrificed and brain tissues were collected for further analysis. Geniposide treatment significantly inhibited cell apoptosis, reduced serum IgG leakage into brain tissue, attenuated astrogliosis and microgliosis, prevented loss of pericytes, loss of tight junction and adherens junction proteins. The PI3K/Akt signaling pathway, which related proteins were downregulated after HI insult, was activated by Geniposide treatment. Geniposide treatment after neonatal HI insult attenuated HI-induced cell apoptosis, IgG leakage, microgliosis, astrogliosis, pericytes loss and junction protein degradation. Geniposide could protect against HI-induced brain injury, which might be through the activation of PI3K/Akt signaling pathway.


Assuntos
Hipóxia-Isquemia Encefálica/tratamento farmacológico , Iridoides/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Feminino , Hipóxia-Isquemia Encefálica/metabolismo , Iridoides/farmacologia , Masculino , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fármacos Neuroprotetores/farmacologia
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