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1.
Int J Biol Macromol ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32057882

RESUMO

The chitin deacetylase CDA3 from C. cinerea deacetylated chitin-oligosaccharides with dp ≥ 2. Since CDA3 firstly removed the intermediate acetyl group of (GlcNAc)4, it was an endo-acting deacetylase. Different from previously reported deacetylation modes, CDA3 deacetylated chitinbiose at either the reducing end or the nonreducing end; CDA3 deacetylated chitintriose at any subsite including the end and the intermediate; CDA3 further removed acetyl groups at any subsite, the intermediate, nonreducing and reducing end of chitintetraose after removal of the first intermediate acetyl group. 3D structural analysis showed that CDA3 has aromatic amino acids distributing at both the +1 and -1 subsites of the catalytic site, which may be responsible for its distinctive deacetylation mode. Furthermore, CDA3 was active on crystalline chitin, its deacetylation activity increased with the DA decreases of chitinous substrates and showed a higher activity towards the cell wall of the basal stipe with the higher molar ratio of GlcN/GlcNAc than that of the apical stipe with the lower molar ratio of GlcN/GlcNAc. CDA3 with distinctive deacetylation mode and activity indicates its function during the maturation of the fruiting bodies of C. cinerea and a potential for preparation of mushroom chitosan for application in the food, cosmetics, and pharmaceutical industries.

2.
BMC Public Health ; 20(1): 150, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005214

RESUMO

BACKGROUND: Food environments have rapidly changed over the past years in China and children have more access to unhealthy food in convenience stores near schools. Since the studies on the association between convenience stores near schools and obesity had inconsistent results and no similar study in China, we conducted a study on the association in Beijing of China, which will provide scientific evidence for the intervention of childhood obesity. METHODS: The study included 2201 students at grade 4 of 37 primary schools in Dongcheng or Miyun district of Beijing. The food environment data was acquired from AMAP, the free web-based geospatial service provider. The numbers of convenience stores were captured within the 800-m network buffer near schools using Geographic Information System. The weight and height of each student were measured by trained health professionals. Students' dietary and physical behaviors and other information associated with obesity were collected with questionnaires for students and their parents. The generalized linear mixed model (GLMM) was used to analyze the data. RESULTS: The average age of the students was 10.2 years (Standard Deviation (SD) = 0.33). The prevalence of obesity in students was 14.9%. The median number of convenience stores within the 800-m network buffer near schools was 24 in two districts. The number of convenience stores near each school varied from 5 to 67 (median: 25) in Dongcheng district and from 1 to 57 (median: 22) in Miyun district. After adjusting for the confounding factors at the family and individual levels, the association between convenience stores and childhood obesity was statistically significant. Additional ten convenience stores near schools were associated with an increased risk of obesity (Odds Ratio (OR) = 1.13, 95% confidence interval (CI): 1.03,1.24, P = 0.011). Compared with less than 24 convenience stores near schools, the students with more than or equal to 24 convenience stores near schools had an increased risk of obesity (OR = 1.49, 95% CI: 1.09, 2.03, P = 0.013). CONCLUSION: The students with more convenience stores near their schools had an increased risk of obesity. The findings provided evidence for developing public health policy to restrict the number of convenience stores near schools to prevent and control childhood obesity.

3.
Food Chem ; 315: 126273, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32032832

RESUMO

Sea cucumber (Stichopus japonicus) is a high-protein food with the potential to release certain peptides through enzymolysis. This work is to explore the characteristics of peptides released from Stichopus japonicus protein in the process of digestion. Hydrolysates were obtained by gastrointestinal digestion and fractioned to <3, 3-10, 10-30 and >30 kDa fractions. Fifty-eight peptides from <3 kDa fraction were characterized using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Hydrolysates could improve glucose uptake of 3 T3-L1 cells and high insulin-induced insulin-resistant Hep G2 cells. Molecular docking showed that the released peptides had similar binding mode with anagliptin, a dipeptidyl peptidase IV (DPP-IV) inhibitor. The <3 kDa fraction in gastro and intestinal digestion showed the greatest DPP-IV inhibitory potency (IC50 0.51 and 0.52 mg/mL, respectively). The results indicated that sea cucumber could be used as a functional food to release antidiabetic peptides through gastrointestinal digestion.

4.
ACS Nano ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053346

RESUMO

Polymeric nanoparticles (NPs) are important category of drug delivery systems, and their in vivo fate is closely associated with delivery efficacy. Analysis of the protein corona on surface of NPs to understand the in vivo fate of different NPs has been shown to be reliable but complicated and time-consuming. In this work, we establish a simple approach for predicting the in vivo fate of polymeric NPs. We prepared a series of poly(ethylene glycol)-block-poly(D,L-lactide) (PEG-b-PLA) NPs with different protein binding behaviors by adjusting their PEG densities, which were determined by analyzing the serum protein adsorption. We further determined the protein binding affinity, denoted as the equilibrium association constant (KA), to correlate with in vivo fate of NPs. The in vivo fate, including blood clearance and Kupffer cell uptake, was studied, and the maximum concentration (Cmax), the area under the plasma concentration-time curve (AUC) and the mean residence time (MRT) were negatively linearly dependent, while Kupffer cell uptake was positively linearly dependent on KA. Subsequently, we verified the reliability of the approach for in vivo fate prediction using poly(methoxyethyl ethylene phosphate)-b-poly(D,L-lactide) (PEEP-b-PLA) and poly(vinylpyrrolidone)-b-poly(D,L-lactide) (PVP-b-PLA) NPs, and the linear relationship between the KA value and their PK parameters further suggest that the protein binding affinity of polymeric NPs can be a direct indicator of their pharmacokinetics.

5.
Arch Virol ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32056004

RESUMO

Hypoviruses are positive-sense single-stranded RNA mycovirus that infect filamentous fungi. However, hypoviruses have not been reported in Bipolaris oryzae, an important phytopathogenic fungus in water bamboo and rice. Here, we report the characterization of a novel hypovirus, tentatively named "Bipolaris oryzae hypovirus 1" (BoHV1), isolated from strain ES35 of B. oryzae infecting water bamboo. The complete genome of BoHV1 consists of 13,596 nucleotides and a poly(A) tail at the 3' end. BoHV1 has single open reading frame (ORF) and encodes a putative polyprotein (4,218 amino acids) containing four potential conserved domains for a papain-like protease, a protein of unknown function (DUF3525), RNA-dependent RNA polymerase (RdRp), and helicase. Phylogenetic analysis of the polyprotein, RdRp, and helicase domains suggested that BoHV1 belongs to the genus Hypovirus within the family Hypoviridae. This is the first report of the presence of a hypovirus in the phytopathogenic fungus B. oryzae.

6.
Br Poult Sci ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32019334

RESUMO

The study objectives were to determine the direct effects of gonadotropin-releasing hormone (GnRH) on the proliferation of ovarian granulosa cells (GCs) and the development of follicles in geese (Anser cygnoides) by colorimetry and ethynyl-2'-deoxyuridine (EdU) cell proliferation assays, in which primary GCs were treated with different concentrations of GnRH agonist (alarelin acetate) and an antagonist (cetrorelix acetate). Differently expressed genes (DEGs) were identified by RNA-sequencing and validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting.The EdU assays showed that the proliferation of GCs was affected by the GnRH agonist and antagonist in a dose-dependent manner. The effect of treatment on cell proliferation was statistically significant at the concentrations of 10-5 mol/l alarelin and 1 mg/l cetrorelix acetate. A total of 134 DEGs (76 downregulated and 58 upregulated for alarelin treatment) and 226 DEGs (90 downregulated and 136 upregulated for cetrorelix) were identified by RNA-sequencing analysis, respectively. Enrichment analysis indicated that DEGs were enriched in the GO terms of cell-cell signalling and cell junctions. The pathways that regulate the development of follicles were identified, including the biological progress of cAMP accumulation, ovulation cycle and vasculature that are essential to follicular selection.The results suggested that GnRH might directly regulate GC proliferation via autocrine or paracrine pathways related to cell junctions. In particular, it was confirmed that the mRNA and protein expression levels of the oestrogen receptor 2 (ESR2) gene, a negative transcription factor involved in follicular maturation and ovulation, were affected by GnRH agonist or antagonist in GCs.In conclusion, GnRH might play an important role in follicular development by changing the expression of genes that participate in cAMP accumulation, ovulation cycle and cell junctions in ovarian GCs.

7.
BMC Anesthesiol ; 20(1): 39, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024465

RESUMO

BACKGROUND: The comparative efficacy of epidural bupivacaine alone and bupivacaine combined with magnesium sulfate in providing postoperative analgesia remains controversial. METHODS: We searched Mediline (OvidSP), EMBASE (OvidSP) and Cochrane Central Register of Controlled Trials (CENTRAL) to identify trials that compared epidural bupivacaine and magnesium sulfate combination (intervention) with bupivacaine alone (control). Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework was used to assess the quality of evidence. RESULTS: Eleven studies fulfilled our inclusion criteria after screening. We found that epidural bupivacaine combined with magnesium sulfate could prolong the time for first rescue analgesics (SMD 4.96; 95% CI [2.75, 7.17], P < 0.00001, I2 = 98%), reduce the number of patients who need rescue analgesics (RR 0.38; 95% CI [0.20, 0.74], P = 0.004, I2 = 75%) and requirement for rescue analgesics (SMD -2.65; 95% CI [- 4.23, - 1.06], P = 0.001, I2 = 96%). CONCLUSIONS: Magnesium suifate as an adjuvant of epidural bupivacaine improved postoperative analgesia. However, we rated the quality of evidence to be very low because of high heterogeneity, imprecise of results and small sample sizes. Furthermore, further large high-quality trials are still needed to confirm the effects of magnesium sulfate on postoperative analgesia.

8.
Biomed Chromatogr ; : e4810, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32043607

RESUMO

Rifampicin is a semi-synthetic broad-spectrum antibiotic obtained from rifamycin B. It is one of the most effective first-line anti-tuberculosis drugs widely used in clinical practice. In the present study, we described a rapid and sensitive method for the determination of rifampin in aquatic products by stable isotope-dilution high liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Samples were extracted with the acetonitrile, degreased by hexane, and then concentrated by nitrogen blowing. After separation by C18 column with mixture of acetonitrile and water as mobile phase, it was determined by HPLC-MS/MS with stable isotope-dilution calibration method. The performance of our method was validated. The limit of detection (LOD) was 0.25 µg kg-1 and the limit of quantification (LOQ) was 0.5 µg kg-1 . At the three spiked levels of 0.5, 1.0 and 5.0 µg kg-1 , the average recoveries of rifampicin in different aquatic products were between 75.28% and 107.6%, and the relative standard deviation ranged from 0.81% to 13.23%. This method was successfully applied for the determination of rifampin in different kinds of aquatic products and rifampicin residue was found in aquatic products obtained from markets in Beijing, China.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32004941

RESUMO

Despite the development of an off-line packed fiber solid phase extraction procedure (PFSPE) for urinary catecholamines, automation remains a challenge. Here, we propose an on-line PFSPE-HPLC procedure for automated sample processing and analysis of urinary catecholamines, with good recovery and precision, to avoid manual operation errors. The on-line PFSPE-HPLC procedure has been thoroughly optimized concerning the gradient, valve switch timing, the effects of complexing reagent and buffer solution, and the stability of the nanofibers. Validation of the developed on-line PFSPE-HPLC protocol in urine yielded satisfactory accuracies of 99.6-104.2%, precision below 7.0%, as well as a linear range from 1 ng/mL to 100 ng/mL with a correlation coefficient of 0.999. The developed protocol is herein presented as a potential technology for automated sample pretreatment for the determination of urinary catecholamines.

10.
Pharmacology ; : 1-11, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32008007

RESUMO

BACKGROUND: Although Platycodin D (PLD) is the main active saponin of Platycodon grandiflorum (PG) and responsible for multiple therapeutic benefits, including antioxidant and antiaging, only few direct demonstrations have been reported on the role of PLD in antiaging process. The present investigation was carried out to elucidate the protection of PLD against aging in vitro and associated molecular mechanisms on H2O2-induced premature senescence model in human -fetal lung diploid fibroblasts 2BS cells. METHODS: The cellular morphology, cell cycle, and senescence-associated ß-galactosidase activity assays were used for senescence-like phenotypes determination in the oxidant challenged model. The oxygen-free radicals reactive oxygen species (ROS), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) determinations were estimated by enzyme-linked immunosorbent assay assay. The potential of the mitochondria mass and the mitochondrial membrane were used to observe the alteration of mitochondria. Western blot analysis was performed to determine the protein expression. RESULTS: The results showed that PLD significantly reversed senescence-like phenotypes in the oxidant challenged model, as well as related molecules expression such as p53, p21, and p16. Moreover, PLD treatment significantly decreased the levels of ROS, 4-HNE, and MDA in H2O2-treated 2BS cells. The mechanisms responsible for the antioxidant and antiaging effects of PLD were investigated, we found that mitochondria under PLD conditions show increase membrane potential ratio and stimulate the proliferation of mitochondria mass. In addition, the protein expression of peroxisome proliferator activated receptor gamma coactivator 1α and its downstream targets, that is, nuclear respiratory factor and mitochondrial transcription factor A were also increased in mitochondrial biogenesis. CONCLUSION: These results indicated that PLD prevented H2O2-induced premature senescence in vitro by improving mitochondrial biogenesis to attenuate age-dependent endogenous oxidative damage. Key Message: The study revealed the antioxidant and antiaging potential of PLD against H2O2-induced premature senescence.

11.
Chembiochem ; 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32009294

RESUMO

Nitrogen (N) is one of the most important nutrients for plant growth. To enhance crop productivity, chemical N fertilizer is commonly applied in agriculture. Biological nitrogen fixation, the conversion of atmospheric N2 to NH3, is an important source of N input in agriculture and represents a promising substitute for chemical N fertilizers. However, nitrogen fixation is only sporadically distributed within bacteria and archaea (diazotrophs). Thus, many biologists hope to reconstitute a nitrogenase biosynthetic pathway in a eukaryotic host with the final aim of developing N2-fixing cereal crops. With the advent of synthetic biology and a deep understanding of the fundamental genetic determinants necessary to sustain nitrogen fixation in bacteria, much progress has been made toward this goal. Transfer of the native and refactored nif (nitrogen fixation) genes to non-diazotrophs has been attempted in model bacteria, yeast, and plants. Specifically, nif genes from Klebsiella oxytoca, Azotobacter vinelandii and Paenibacillus polymyxa have been successfully transferred and expressed in Escherichia coli, Saccharomyces cerevisiae and even in tobacco plant. These advances have laid the groundwork to enable cereal crops to "fix" nitrogen themselves to sustain their growth and yield.

12.
World Neurosurg ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32035204

RESUMO

An 11-year-old girl underwent posterior spinal fusion surgery for scoliosis. The surgery was complicated with intraoperative bleeding and hemostasis was achieved by topically applying gelatin sponges. She suffered from acute pulmonary embolism and cardiac arrest during the surgery which was confirmed by TEE. Autopsy shortly after revealed that her death was associated with unintended intravascular entry of gelatin sponge fragments resulting in embolic event and secondary cardiopulmonary collapse.

13.
J Physiol ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32052864

RESUMO

KEY POINTS: During exercise, blood pressure (BP) response is exaggerated in peripheral artery disease (PAD). We examined whether heat treatment (HT) has beneficial effects on the exaggerated exercise pressor reflex in PAD rats. With HT (increase in the Tm of ∼1.5°C for 30 min, 2 times daily for 3 continuous days), the amplified BP response to muscle contraction is alleviated in PAD. We demonstrated that HT attenuates the enhancement of the BP response induced by stimulation of P2X in muscle afferent nerves of PAD rats. HT also attenuates the upregulation of the P2X3 and the increase in P2X currents in the muscle afferent neurons of PAD rats. Prior heat exposure plays a beneficial role in modifying the exaggeration of the exercise pressor reflex in PAD and a reduction in the activity of the P2X receptor pathway is likely a part of the mechanism mediating this improvement. ABSTRACT: The current study was performed to examine if heat treatment (HT) has beneficial effects on the exaggerated exercise pressor reflex in rats with peripheral artery disease (PAD). We further determined if the temperature sensitive P2X receptor is involved in the effects of HT. The pressor response to static muscle contraction and α, ß-methylene ATP (αß-me ATP, a P2X agonist) was examined. Western blot analysis was used to determine the protein levels of P2X3 in the dorsal root ganglion (DRG), and the whole cell patch clamp was used to examine the amplitude of P2X currents in the DRG neurons. The basal muscle temperature (Tm) was lower in PAD rats than in control rats. As the Tm was increased by ∼1.5°C and this increase was maintained for 30 min. This HT protocol was performed 2 times daily for 3 continuous days. A greater blood pressure (BP) response to contraction was observed in PAD rats. HT attenuated the amplification of the BP response in PAD rats. HT also attenuated the enhancement of the BP response induced by the arterial injection of αß-me ATP in PAD rats. In addition, HT attenuated the upregulation of the P2X3 and increased P2X currents in the DRG neurons of PAD rats. In conclusion, prior heat exposure plays an inhibitory role in modifying the exaggeration of the exercise pressor reflex in PAD and a reduction of the activity of the P2X receptor pathway is likely a part of mechanisms leading to the beneficial effects of HT. This article is protected by copyright. All rights reserved.

14.
Sensors (Basel) ; 20(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012920

RESUMO

Emotion recognition and monitoring based on commonly used wearable devices can play an important role in psychological health monitoring and human-computer interaction. However, the existing methods cannot rely on the common smart bracelets or watches for emotion monitoring in daily life. To address this issue, our study proposes a method for emotional recognition using heart rate data from a wearable smart bracelet. A 'neutral + target' pair emotion stimulation experimental paradigm was presented, and a dataset of heart rate from 25 subjects was established, where neutral plus target emotion (neutral, happy, and sad) stimulation video pairs from China's standard Emotional Video Stimuli materials (CEVS) were applied to the recruited subjects. Normalized features from the data of target emotions normalized by the baseline data of neutral mood were adopted. Emotion recognition experiment results approved the effectiveness of 'neutral + target' video pair simulation experimental paradigm, the baseline setting using neutral mood data, and the normalized features, as well as the classifiers of Adaboost and GBDT on this dataset. This method will promote the development of wearable consumer electronic devices for monitoring human emotional moods.

16.
Environ Sci Technol ; 54(3): 2022-2030, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31909975

RESUMO

Mercury emission from industrial activities is a great threat to public health and ecosystems. Developing new strategies and materials to remove mercury still remains a serious task. Herein, selenide-decorated copper foam prepared by a heating-stirring method (Cu-hs) was used as a monolithic mercury adsorption material. The Cu-hs exhibited much better adsorption of elemental mercury (Hg0) compared with the selenide-decorated cordierite honeycomb prepared by the same method (Cordierite-hs). Nearly 100% Hg0 adsorption efficiency was obtained under a high gaseous hourly space velocity of 6.0 × 104. Excellent Hg0 adsorption capacity was obtained in a wide range of reaction temperatures from 40 to 120 °C, suggesting the good adaptability of Cu-hs in different operating conditions. The Cu-hs exhibited high selectivity for Hg0 against H2O and SO2, which is advantageous for real applications in industrial flue gas. The Hg0 adsorption capacity of Cu-hs reached 3743 g/m3, about 14 times higher than the 243 g/m3 of Cordierite-hs. The excellent Hg0 adsorption performance of Cu-hs was attributed to the high affinity of the selenium in Cu2Se for mercury, the homogeneous distribution of Cu2Se, and the superior fluid characteristics of the Cu foam substrate. The adsorption performance of the spent Cu-hs could be effectively recovered by HCl solution leaching and subsequent reselenization. The utilization of recyclable Cu-hs provides a cost-effective and environmentally friendly method for removing mercury from industrial flue gas.

17.
Chin J Integr Med ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31919749

RESUMO

OBJECTIVE: To evaluate the effects of a 48-week course of adefovir dipivoxil (ADV) plus Chinese medicine (CM) therapy, namely Tiaogan Jianpi Hexue () and Tiaogan Jiedu Huashi () fomulae, in hepatitis B e antigen (HBeAg)-positive Chinese patients. METHODS: A total of 605 HBeAg-positive Chinese CHB patients were screened and 590 eligible participants were randomly assigned to 2 groups in 1:1 ratio including experimental group (EG, received ADV plus CM) and control group (CG, received ADV plus CM-placebo) for 48 weeks. The major study outcomes were the rates of HBeAg and HBV-DNA loss on week 12, 24, 36, 48, respectively. Secondary endpoints including liver functions (enzymes and bilirubin readings) were evaluated every 4 weeks at the beginning of week 24, 36, and 48. Routine blood, urine, and stool analyses in addition to electrocardiogram and abdominal B scan were monitored as safety evaluations. Adverse events (AEs) were documented. RESULTS: The combination therapy demonstrated superior HBeAg loss at 48 weeks, without additional AEs. The full analysis population was 560 and 280 in each group. In the EG, population achieved HBeAg loss on week 12, 24, 36, and 48 were 25 (8.90%), 34 (12.14%), 52 (18.57%), and 83 (29.64%), respectively; the equivalent numbers in the CG were 20 (7.14%), 41 (14.64%), 54 (19.29%), and 50 (17.86%), respectively. There was a statistically significant difference between these group values on week 48 (P<0.01). No additional AEs were found in EG. Subgroup analysis suggested different outcomes among treatment patterns. CONCLUSION: Combination of CM and ADV therapy demonstrated superior HBeAg clearance compared with ADV monotherapy. The finding indicates that this combination therapy may provide an improved therapeutic effect and safety profile (ChiCTR-TRC-11001263).

18.
Sci Rep ; 10(1): 121, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924832

RESUMO

In this study, we determined the influences of different drying techniques such as natural air (ND), hot-air (HD), vacuum (VD), infrared (ID), microwave (MD), and freeze drying (FD) methods on the color, shrinkage ratio (SR), rehydration ratio (RR), firmness, crispness, microstructures, nutritional components, and free amino acids of Pleurotus eryngii. The results showed that these parameters were markedly influenced by different drying techniques. Among them, FD was the most effective drying method which retained the main characteristics of the fresh P. eryngii in above mentioned indexes, followed by ND and HD at 40 °C. Finally, despite the least drying time, MD treatment was not suitable to the drying process of P. eryngii slices since it damaged physicochemical properties and caused massive losses of the main nutrients and free amino acids. The results will provide a theoretical basis for industrial processing of P. eryngii.

19.
Sleep Breath ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907823

RESUMO

PURPOSE: Intermittent hypoxia is a characteristic pathological change in obstructive sleep apnoea (OSA) that can initiate oxidative stress reaction and pro-inflammatory cytokine release. The purpose of this study was to assess the effect and protective mechanism of Astragaloside IV (AS-IV) in intermittent hypoxia-induced human lung epithelial Beas-2B cells. METHODS: Human lung epithelial Beas-2B cells were exposed to intermittent hypoxia or normoxia in the absence or presence of AS-IV. MTT assay was performed to determine the cell viability. The levels of reactive oxygen species (ROS), lactate dehydrogenase (LDH), malonaldehyde (MDA), and superoxide dismutase (SOD) were measured to evaluate oxidative stress. The levels of cytokines interleukin (IL)-8, IL-1ß, and IL-6 were evaluated by enzyme-linked immunosorbent assay and real-time PCR. The expression of Toll-like receptor 4 (TLR4), mitogen-activated protein kinase (MAPK), and nuclear transcription factor-kappa B (NF-κB) signalling pathways was analysed by western blot. RESULTS: The results showed that AS-IV significantly reduced the levels of ROS, LDH, MDA, IL-8, IL-1ß, and IL-6, and increased the level of SOD in intermittent hypoxia-induced Beas-2B cells. It also suppressed the phosphorylation of MAPKs, including P38, c-Jun N-terminal kinase and extracellular signal-regulated kinase, and inhibited the activation of the NF-κB signalling pathway by reducing the phosphorylation of IκBα and p65. CONCLUSIONS: AS-IV attenuates inflammation and oxidative stress by inhibiting TLR4-mediated MAPK/NF-κB signalling pathways in intermittent hypoxia-induced Beas-2B cells.

20.
J Mater Chem B ; 8(6): 1202-1211, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31942915

RESUMO

The development of nanotheranostic agents integrating diagnosis and therapy has gained tremendous attention in the past few decades, but many of them are inherently hydrophobic and need complicated phase-transfer and tedious surface modifications. This work proposed a facile method of transferring hydrophobic Fe3O4@Cu2-xS nanoparticles from oil to water by using red blood cell membrane to create theranostic nanobeads for T2-weighted MRI and second near-infrared photothermal ablation. The obtained nanoplatform, namely SCS@RBCM, showed a core-shell structure with the inner core densely packed with Fe3O4@Cu2-xS nanoclusters and the surface coated with a layer of RBCM. SCS@RBCM displayed a stable nanostructure, high NIR II light absorption and photothermal conversion ability, T2-weighted MR imaging and magnetic field targeting ability. Meanwhile, the RBCM cloaking endowed SCS with reduced elimination by macrophages. With the navigation of an external magnetic field (MF), the tumor accumulation of SCS@RBCM was dramatically increased, thus achieving good performance of MR imaging and antitumor efficacy through the PTT effect under NIR II irradiation. Therefore, our strategy presents a new and desirable paradigm in the phase-transfer of hydrophobic nanotheranostics for optimizing their biomedical performance.

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