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1.
Med Sci Monit ; 26: e919820, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31902939

RESUMO

BACKGROUND Thyroid cancer is the most common endocrine system malignancy. Scientists have done considerable research into the molecular mechanisms involved, but many mechanisms remain undiscovered. MATERIAL AND METHODS We performed a comprehensive analysis of the whole-transcriptome resequencing derived from thyroid tissues and paired papillary thyroid cancer (PTC) and showed that lysophosphatidic acid receptor 5 (LPAR5) is strongly overexpressed in thyroid carcinoma. Then, we used TPC-1 and KTC-1 to explore the effect of LPAR5 knockdown on colony formation, migration, proliferation, invasion, and apoptosis of PTC cell line cells. AKT activator was used for the recovery test. Finally, we designed proteomic experiments to explore the role of LPAR5 in the AKT pathway and the EMT process. RESULTS Cell function experiments showed that LPAR5 knockdown can significantly induce apoptosis of KTC-1 and TPC-1 cells. Furthermore, LPAR5 can promote PTC metastasis and tumorigenesis by activating the PI3K/AKT pathway and decreasing its cancer-promoting effect when using AKT agonist. We also found that LPAR5 can regulate the expression of EMT-related proteins, which affect invasion and migration. CONCLUSIONS In summary, downregulation of LPAR5 expression can inhibit the physiological process of PTC, and this phenomenon is related to the PI3K/AKT pathway and EMT.

2.
Huan Jing Ke Xue ; 41(1): 273-283, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854928

RESUMO

We determine the efficiency and mechanism of Mg/Fe layered double hydroxides (Mg/Fe-LDH) addition for the control of phosphorus (P) release from sediments by studying the adsorption behavior and mechanism of phosphate from an aqueous solution on Mg/Fe-LDH. The impact of Mg/Fe-LDH addition on the mobilization of P in sediments as well as the adsorptive removal of phosphate by sediments is investigated, and the stabilization of P bound by Mg/Fe-LDH is also evaluated. Results showed that the kinetics data of phosphate adsorption onto Mg/Fe-LDH fitted better with the Elovich kinetics model than with the pseudo-first-order and pseudo-second-order kinetics models, and that the Freundlich and Dubinin-Radushkevich models were more suitable for describing the adsorption isotherm behavior of phosphate on Mg/Fe-LDH than the Langmuir model. Phosphate adsorption possessed a wide effective pH range of 4-10. Coexisting Ca2+ and Mg2+ enhanced phosphate adsorption onto Mg/Fe-LDH, while coexisting Na+, K+, and Cl- had negligible impacts on the phosphate adsorption. The presence of SO42- and HCO3- in aqueous solution inhibited the adsorption of phosphate on Mg/Fe-LDH. The phosphate adsorption mechanisms were deduced to be anion exchange, electrostatic attraction, ligand exchange and inner-sphere complex formation. The addition of Mg/Fe-LDH into sediments not only greatly reduced the concentration of reactive soluble P (SRP) in the overlying water, but also significantly decreased the level of SRP in the pore water. In addition, Mg/Fe-LDH addition also increased the adsorption capacity for the sediments, and the phosphate adsorption ability for the Mg/Fe-LDH-amended sediments increased with increased amendment dosage. Almost half of the phosphate bound by Mg/Fe-LDH existed in the form of relatively stable P, i.e., metal oxide-bound P (NaOH-rP), which was difficult to release back into the water column under normal pH and anoxic conditions. Nearly half of the phosphate bound by Mg/Fe-LDH existed in the form of easily released P, i.e., NH4Cl extractable P (NH4Cl-P) and redox-sensitive P (BD-P), which had a high risk of re-releasing into the water column. We conclude that it is very necessary for Mg/Fe-LDH to be recycled from the sediments after the application of Mg/Fe-LDH as an amendment to control sedimentary P liberation.

3.
Langmuir ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31885276

RESUMO

Because of the unique optical properties of gold nanomaterials, the preparation of gold nanomaterials with excellent chirality has received extensive attention. In order to develop a simple fabrication method for three-dimensional chiral Au nanostructures with a size of several hundred nanometers, chiral gold nanoparticles were developed to transfer chirality of a peptide to gold nanoparticles. In this study, the controlled synthesis of asymmetric gold nanopolyhedrons was achieved. The asymmetric gold nanopolyhedrons prepared via peptide-directed growth can exhibit strong circular dichroism (∼±50 mdeg) couplets in the visible range (500-600 nm). Also, the morphology of chiral Au nanododecahedrons-peptide particles showed distorted and asymmetric properties. In order to prove that the size and spatial structure of gold nanopolyhedrons have an influence on their chiral optical properties, Au nanotrioctahedron-peptide particles were prepared by using Au nanotrioctahedrons with different morphologies. Au nanotrioctahedron-peptide particles also exhibited circular dichromatic couplets in the visible region.

4.
Food Funct ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31819940

RESUMO

Mallotus oblongifolius (MO), an edible medicinal plant from Hainan in China, shows a wide range of bioactivities. The daily consumption of MO or its extracts has been observed to ameliorate ischemic nerve injury. However the mechanisms remain unclear. In this study, the effects of MO both in vitro and in vivo were investigated. The results indicated that MO improved the motor ability, neurosensory ability, balance and grasping ability of mice with ischemic injuries, induced by bilateral common carotid artery ligation (BCCAL). In addition, MO improved the morphology of neurons, resisted the loss of neurons, and enhanced the content of the nestin protein in the cerebral cortex and subgranular zone (SGZ) area. Furthermore, in the oxygen-glucose deprivation and reperfusion (OGD/R) treated cell model, MO could effectively activate the Wnt/ß-catenin signaling pathway and promote the proliferation of neural stem cells (NSCs) and increase the protein expression levels of ß-catenin and CyclinD1. Our results suggest that Mallotus oblongifolius may be used as nutraceuticals or functional foods to alleviate ischemic nerve damage and promote recovery from ischemic stroke.

5.
J Therm Biol ; 86: 102448, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31789236

RESUMO

Human thermal adaptation is an important factor of indoor thermal comfort and energy conservation. To study the effect of indoor thermal history on cold adaptation in the early winter, climate chamber tests were conducted in cold environments at 16 °C with two different thermal experience groups. The groups are divided as follows: the natural ventilation (NV) group consisted of subjects living in naturally ventilated buildings (approximately 11.8 ±â€¯3.4 °C in winter (Liu, H., Wu, Y., Li, B., Cheng, Y., Yao, R., 2017. Seasonal variation of thermal sensations in residential buildings in the Hot Summer and Cold Winter zone of China. Energy and Buildings 140, 9-18)) and the air conditioning (AC) group consisted of subjects living in air-conditioned buildings for at least one year before the climate chamber experiments. The experiments on the NV and AC groups were conducted between December 1-13 and December 15-25, respectively. Each group consisted of 20 subjects wearing winter clothes (1.15 ±â€¯0.05 clo). The thermal sensation votes (TSVs) and thermal comfort votes (TCVs) in both groups were investigated and the subjects' skin temperatures were monitored during the experiments. The results showed that the mean TCV and TSV of both groups were not significantly different in the early winter. However, differences were observed in the subjects' localized body parts. The skin temperatures of the chest and arms of subjects in the NV group were higher than those in the AC group after exposure for 60 min at 16 °C, while calves skin temperatures of subjects in the NV group were lower. In addition, subjects in the AC group were found to feel colder compared to those in the NV group in cold environments at the same skin temperature. Thus, this study provides information about thermal comfort based on thermal experience in early winter.

6.
Molecules ; 24(23)2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801194

RESUMO

Two new octanorlanostane-type triterpenes, euphraticanoids A and B (1 and 2), two new trinorsesquiterpenoids, euphraticanoids C and D (3 and 4), and eight known triterpenoids (5, 6, 8-13) along with one steroid (7) were isolated from Populus euphratica resins. The structures of these new compounds, including their absolute configurations, were characterized by spectrocsopic, chemical, and computational methods. Biological evaluation revealed that compounds 4, 7-9, 12, and 13 display neuroprotective activities in H2O2-induced HT-22 cells with 4, 8, and 9 occurring in a concentration-dependent manner and 7, 12, and 13 reaching the maximum effects at 20 µM. Meanwhile, the neuroprotective properties of all isolates were accessed using glutamate-induced SH-SY5Y cells and disclosed that compounds 3, 4, 8, and 9 could dose-dependently protect neural cell injury in a concentration range of 10-40 µM. Finally, a brief structure-activity relationship was briefly discussed.

7.
Clin Exp Optom ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802528

RESUMO

BACKGROUND: To evaluate the refractive outcomes in children treated with intravitreal injection of ranibizumab (IVR) for retinopathy of prematurity (ROP). METHODS: A retrospective study of 95 patients (186 eyes) was conducted. All patients received IVR treatment. The cycloplegic refraction was evaluated at three months, six months, 12 months and 24 months. RESULT: The average spherical equivalent (SE) refraction value for patients with ROP who were treated with IVR as a monotherapy at the three, six, 12 and 24 months was +1.84 ± 2.11 D, +1.02 ± 2.41 D, +0.43 ± 2.23 D and +0.13 ± 2.73 D, respectively (p < 0.001). Myopia (SE < -0.25 D) was observed in 24 eyes (15.9 per cent) at the three-month follow-up, 33 eyes (21.8 per cent) at the six-month follow-up, 33 eyes (26.5 per cent) at the 12-month follow-up and 34 eyes (37.5 per cent) at the 24-month follow-up, respectively (p < 0.05). The percentage of eyes with high myopia (SE < -5.0 D) was 0.6 per cent, 1.4 per cent, 1.7 per cent and 3.4 per cent at the three-month, six-month, 12-month and 24-month follow-up visits in the IVR group. There were 59 eyes that received repeated IVR injections at the follow-ups. The average SE of patients receiving repeated injections at the three-, six-, 12- and 24-month visits was +1.53 ± 2.03 D, +1.25 ± 1.95 D, +0.58 ± 2.24 D and -0.17 ± 3.22 D, respectively (p = 0.04). CONCLUSION: Our large sample study found that 37.5 per cent and 3.4 per cent of patients treated with IVR developed myopia and high myopia respectively, at the 24-month follow-up. Furthermore, the mean SE decreased, and the trend of myopia increased, in the IVR group at the follow-ups. Repeated injections might promote myopia in ROP patients. The refractive status needs to be monitored in patients treated with ranibizumab.

8.
Nano Lett ; 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31846340

RESUMO

Full exploitation of graphene's superior properties requires the ability to precisely control its morphology and edge structures. We present such a structure-tailoring approach via controlled atom removal from graphene edges. With the use of a graphitic-carbon-capped tungsten nanoelectrode as a noncontact "milling" tool in a transmission electron microscope, graphene edge atoms approached by the tool tip are locally evaporated, thus allowing a freestanding graphene sheet to be tailored with high precision and flexibility. A threshold for the tip voltage of 3.6 ± 0.4 V, independent of polarity, is found to be the determining factor that triggers the controlled etching process. The dominant mechanisms involve weakening of carbon-carbon bonds through the interband excitation induced by tunneling electrons, assisted with a resistive-heating effect enhanced by high electric field, as elaborated by first-principles calculations. In addition to the precise shape and size control, this tip-based method enables fabrication of graphene edges with specific chiralities, such as "armchair" or "zigzag" types. The as-obtained edges can be further "polished" to become entirely atomically smooth via edge evaporation/reconstruction induced by in situ TEM Joule annealing. We finally demonstrate the potential of this technique for practical uses through creating a graphene-based point electron source, whose field emission characteristics can effectively be tuned via modifying its geometry.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31884532

RESUMO

Soil methane generation mainly driven by soil prokaryotic microbes can be coupled with the degradation of petroleum hydrocarbons (PHCs); however, the relationship between prokaryotic community structure and methane production activity in soil with the potential risk of PHC contamination is seldom reported. In this study, 3 soil samples (CS-1 to CS-3) in the area nearby an exploratory gas well and 5 soil samples (DC-1 to DC-5) in a drill cutting dump area were obtained from the Fuling shale gas field (Chongqing City, China). Then, the prokaryotic community structure was examined by Illumina Miseq sequencing, and the linkage between soil methane production rate (MPR) and prokaryotic community composition was analyzed. The results indicated that 2 samples (DC-4 and DC-5) collected from the drill cutting dump area had significantly higher MPR than the other samples, and a significant and positive relationship (r = 0.44, P < 0.05) was found between soil MPR and soil organic matter (OM) content. The prokaryotic community composition in the sample (DC-5) with the highest MPR was different from those in the other samples, and soil OM and MPR were the major factors significantly correlated with the prokaryotic community structure in this soil. The samples (DC-4 and DC-5) with higher MPR had a higher relative abundance of Archaea and different archaeal community structures from the other samples, and the MPR was the sole factor significantly correlated with the archaeal genus composition in this soil. Therefore, both the prokaryotic and archaeal community structures are essential in the determination of soil MPR, and the bacterial genus of Saccharibacteria and the archaeal genus of Methanolobus might be the key contributors for methane generation in this soil from the shale gas field.

10.
Aging (Albany NY) ; 11(24): 12202-12212, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31860872

RESUMO

Abnormal ß-amyloid (Aß) levels were found in patients with Down syndrome (DS). However, Aß levels in patients with DS and DS with dementia (DSD) vary considerably across studies. Therefore, we performed a systematic literature review and quantitatively summarized the clinical Aß data on the cerebrospinal fluid (CSF) and blood of patients with DS and those with DSD using a meta-analytical technique. We performed a systematic search of the PubMed and Web of Science and identified 27 studies for inclusion in the meta-analysis. Random-effects meta-analysis indicated that the levels of blood Aß1-40 and Aß1-42 were significantly elevated in patients with DS compared with those in healthy control (HC) subjects. In contrast, there were no significant differences between patients with DS and those with DSD in the blood Aß1-40 and Aß1-42 levels. The CSF Aß1-42 levels were significantly decreased in patients with DS compared to those in HC subjects. Further, CSF Aß1-42 levels were significantly decreased in patients with DSD compared to those with DS, with a large effect size. Taken together, our results demonstrated that blood Aß1-40 and Aß1-42 levels were significantly increased in patients with DS while CSF Aß1-42, but not Aß1-40 levels were significantly decreased in patients with DS.

11.
Nat Commun ; 10(1): 5048, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31695122

RESUMO

Metal-organic frameworks (MOFs) have been recognized as compelling platforms for the development of miscellaneous applications because of their structural diversity and functional tunability. Here, we propose that the electrocatalytic properties could be well modified by incorporating missing linkers into the MOF. Theoretical calculations suggest the electronic structure of MOFs can be tuned by introducing missing linkers, which improves oxygen evolution reaction (OER) performance of the MOF. Inspired by these aspects, we introduced various missing linkers into a layered-pillared MOF Co2(OH)2(C8H4O4) (termed as CoBDC) to prepare missing-linker MOFs. Transmission electron microscope and synchrotron X-ray measurements confirmed that the missing linkers in the MOF could be introduced and well controlled by our strategy. The self-supported MOF nanoarrays with missing linkers of carboxyferrocene exhibit excellent OER performance with ultralow overpotential of 241 mV at 100 mA cm-2. This work opens a new prospect to develop efficient MOF-based electrocatalysts by introducing missing linkers.

12.
Oncol Rep ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31746412

RESUMO

The present study aimed to assess the performance of positron emission tomography­magnetic resonance imaging (PET/MR) for the visualization and characterization of lesions. In addition, the present study investigated whether the apparent diffusion coefficient (ADC) and intravoxel incoherent motion parameters exhibited any significant correlation with standardized uptake values (SUV) in patients with nasopharyngeal carcinoma (NPC). A total of 35 patients with NPC underwent whole body PET­computed tomography (CT) and head and neck MR imaging (MRI) scans using the PET/CT­MRI system. Image quality, lesion conspicuity and the diagnostic confidence of PET/CT, T1 weighted (T1w) PET/MR and T2w PET/MR imaging were assessed. The true diffusion coefficient (D), the pseudo­diffusion coefficient or diffusion within the microcirculation (D*), and the perfusion fraction or the contribution of water moving in the capillaries (f), and ADC, were calculated. The correlation between the ADC, D*, D and f values and the SUV were analyzed using Pearson's correlation analysis. Similar image quality was obtained using PET/CT, T1w PET/MR and T2w PET/MR imaging. However, the T1w PET/MR and T2w PET/MR imaging were more effective than PET/CT in analyzing the lesion conspicuity of the primary tumors and lymph nodes. In addition, T2w PET/MR imaging was more efficient than T1w PET/MR imaging in analyzing primary tumors and lymph nodes. Pearson's correlation analysis showed no significant correlation between the SUV and ADC, and D*, D and f values in NPC. The present results suggested that the application of PET/MR is feasible and could serve as a reliable alternative to PET/CT, while SUV and ADC, D*, D and f values were identified as independent biomarkers in NPC.

13.
J Mech Behav Biomed Mater ; 103: 103529, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31783283

RESUMO

The cutting of tooth enamel using a high-speed air-turbine handpiece and carbide bur is a key procedure in oral surgeries, such as the minimally invasive extraction. However, presently little is known about the cutting mechanics and material removal mechanism related to tooth enamel machinability. In this study, the machinability of high-speed enamel cutting with carbide bur is studied by a computer-aided numerical control system. The dynamic cutting forces of enamel of the occlusal, buccal/lingual, and proximal surfaces were measured by the force measuring system. The force ratio, cutting torque, rotating speed, specific cutting energy, and bur wear were analyzed. The microstructure of enamel and carbide burs was observed by the scanning electron microscope, and the relationship between enamel microstructures and machinability was further analyzed. The results show that during the high-speed enamel cutting with carbide bur, the chip thickness is on the nano-scale, and the plastic deformation of the machined surface is obvious. With increased material removal rate, the cutting force, torque, specific cutting energy, and bur wear increases accordingly, whereas the rotating speed decelerates (p < 0.05). The different angles between the cutting direction and the axial direction of the enamel rods give rise to the large differences in the cutting mechanics and mechanism of the proximal, buccal/lingual, and occlusal surfaces of the teeth. When the cutting direction is parallel, vertical, and oblique 45° to the axial direction of the enamel rods, the force required for material fracture and crack propagation increases, and the cutting force increases as a consequence. Parallel and oblique 45° cutting are the main modes of tooth segmentation in the minimally invasive extraction. In comparison with the parallel cutting mode, the cutting force, torque, and cutting ratio of the oblique 45° cutting mode can be significantly increased, and the tool wear is obviously accelerated. This is the lowest priority in segmentation surgery, hence the problems of overload and temperature rise need to be considered. The cutting mechanics and cutting mechanism obtained in this study will provide scientific process guidance for dental cutting operations with the air-turbine handpiece driving bur.

14.
J Food Sci ; 84(12): 3411-3417, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31750940

RESUMO

Aroma assessment remains difficult and uncertain in the present sensory assessment system. It is highly desirable to develop a new assessment method to discriminate the quality of various teas in the tea market. In the present work, based on linear discriminant analysis and principal component analysis, the aroma of dry and wet samples of different Xi-hu Longjing and Pu-erh teas were tested and differentiated by electronic noses (e-nose). The results confirm that e-nose can discriminate different priced Xi-hu Longjing tea samples in the range of 80-800 RMB/500 g and varying storage years of Pu-erh tea samples. Furthermore, for the detection of both dry and wet samples of Longjing and Pu-erh teas, the results reveal that all samples have specific aroma characteristics that e-nose can recognize. More importantly, contribution analysis in sensors indicates that nitrogen oxides, methane and alcohols are the characteristic components that contribute to the fragrances of different priced Xi-hu Longjing teas, while nitrogen oxides, aromatic benzene and amines make the fragrances of Pu-erh teas with different storage years disparate. PRACTICAL APPLICATION: This work demonstrates that e-nose can rapidly distinguish tea products with different price levels and varying storage years. With the advantages of ease of use, high portability and flexibility, e-nose will be widely expanded and applied in refined processing and the development of flavored foods.

15.
Schizophr Bull ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31738422

RESUMO

Prenatal administration of mitotoxin methylazoxymethanol acetate (MAM) in rats produces behavioral, pharmacological, and anatomical abnormalities once offspring reach adulthood, thus establishing a widely used neurodevelopmental model of schizophrenia. However, the molecular aspects underlying this disease model are not well understood. Therefore, this study examines epigenetic and transcriptional dysregulation in the prefrontal cortex and hippocampus of MAM rats as these are brain regions closely associated with schizophrenia pathogenesis. Upon sequencing messenger and microRNA (mRNA and miRNA, respectively), differential expression was revealed in the prefrontal cortex and hippocampus between MAM- and saline-treated rats; sequencing data were validated by qualitative real-time polymerase chain reaction. Bioinformatic analyses demonstrated that the differentially expressed (DE) genes were strongly enriched in interactive pathways related to schizophrenia, including chemical synaptic transmission, cognition, and inflammatory responses; also, the potential target genes of the DE miRNAs were enriched in pathways related to synapses and inflammation. The blood of schizophrenia patients and healthy controls was further analyzed for several top DE mRNAs: DOPA decarboxylase, ret proto-oncogene, Fc receptor-like 2, interferon lambda receptor 1, and myxovirus (influenza virus) resistance 2. The results demonstrated that the expression of these genes was dysregulated in patients with schizophrenia; combining these mRNAs sufficiently differentiated schizophrenia patients from controls. Taken together, this study suggests that the MAM model has the potential to reproduce hippocampus and prefrontal cortex abnormalities, relevant to schizophrenia, at the epigenetic and transcriptional levels. These data also provide novel targets for schizophrenia diagnoses and treatments.

16.
Nat Prod Res ; : 1-7, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31741407

RESUMO

Two new mertoterpenoids, australins A (1) and B (2), and a new alkaloid, australine (4), together with five known compounds (3, 5-8) were isolated from the fruiting bodies of Ganoderma australe. Their structures including absolute configurations were assigned by using spectroscopic methods and electronic circular dichroism (ECD) calculations. Racemic australin A was further purified by chiral HPLC. Biological assessments reveal that compounds (+)-1 and 7 could significantly protect SH-SY5Y cells from glutamate-induced neural excitotoxicity.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31758622

RESUMO

The chemical nanospace confinement effect on the physicochemical properties of host-guest systems is of pivotal interest to enzyme-mimicking study. Herein we demonstrate a nanocage coupling effect from a redox Ru(II)-Pd(II) metal-organic cage (MOC-16) for efficient photochemical H 2 production by virtue of redox-guest modulation of the photo-induced electron transfer (PET) process. Through coupling with photoredox cycle of MOC-16, tetrathiafulvalene (TTF) guests act as electron relay mediator to improve the overall electron transfer efficiency in the host-guest system in a long-time scale, leading to significant promotion of visible-light driven H 2 evolution. By contrast, the presence of larger TTF-derivatives in bulk solution without host-guest interactions results in interference with PET process of MOC-16, leading to inefficient H 2 evolution. Such interaction protocol provides an example to understand the interplay between redox active nanocage and guest for optimization of redox events and photocatalytic activities in a spatially confined chemical nanoenvironment, which might be extendable to other enzyme-mimicking photochemical molecular device (PMD) at a supramolecular level.

18.
Inorg Chem ; 58(21): 14652-14659, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31603662

RESUMO

The development of cost-effective, high-performance, and robust bifunctional electrocatalysts for overall water splitting remains highly desirable yet quite challenging. Here, by selecting appreciate precursors of dopamine and a Co-containing metal-organic framework of ZIF-67, we subtly couple their reaction processes to develop a facile approach for the synthesis of a hollow CoP nanostructure with N-doped carbon skeleton (H-CoP@NC). Benefiting from the highly porous nanostructure and conductive carbon skeleton, H-CoP@NC is capable of working as highly active and durable bifunctional electrocatalyst for both hydrogen and oxygen evolution reaction. When further used as the electrocatalyst for overall water splitting, H-CoP@NC delivers excellent activity (cell voltage of 1.72 V at a current density of 10 mA cm-2), close to that of the noble-metal-based benchmark catalyst couple of Pt/C||RuO2. Our work thus provides new insights into the development of transitional metal phosphides based hollow hybrid nanostructures, particularly those with multiple functionalities in sustainable energy conversion technologies and systems.

19.
Chem Biodivers ; 16(11): e1900416, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31631505

RESUMO

The frequent disease of Panax notoginseng caused by the pathogenic fungi in field cultivation has become the major threaten to the sustainable development of it. The present study was conducted to find natural agent with potential inhibition against pathogen. Therefore, the inhibitory effects of Cinnamomum cassia (L.) J.Presl essential oils (EOs) against P. notoginseng associated pathogenic fungi were conducted both in vitro and in vivo experiments. The results of the Oxford cup test revealed that C. cassia dry bark EO (50 mg/mL) had significant inhibitory activity on the growth of all tested fungi, and the growth of various pathogens was completely inhibited, except for that of Fusarium solani. Therefore, the constituents of C. cassia EOs were analyzed by GC/MS, and the research demonstrated that the main constituents of C. cassia dry bark EO were trans-cinnamaldehyde (75.65 %), (E)-2-methoxycinnamaldehyde (6.08 %), cinnamaldehyde (3.47 %) and cinnamyl acetate (1.02 %). The MIC results showed that C. cassia dry bark EO and the main compounds had good antifungal effect on the tested strains, and the inhibitory effect was similar to that of hymexazol (chemical pesticide). By analyzing the value of the fraction inhibitory concentration index (FICI), additive effects, irrelevant effects and synergistic effects were observed after the mixture of hymexazol against various pathogens. Moreover, in vivo model showed that C. cassia dry bark EO could reduce the occurrence of anthrax in P. notoginseng. To widen the resources of C. cassia available, the compositions of both C. cassia fresh bark and leaf EOs were also tested and many common compositions existed among them. Taken together, it was concluded that C. cassia EO had the potential use in the field to reduce the pathogenic disease.

20.
Arch Toxicol ; 93(11): 3305-3320, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612242

RESUMO

Aflatoxin B1 (AFB1), a food contaminant derived from Aspergillus fungi, has been reported to cause hepatic immunotoxicity via inflammatory infiltration and cytokines release. As a pro-inflammatory factor, cyclooxygenase-2 (COX-2) is widely involved in liver inflammation induced by xenobiotics. However, the mechanism by which AFB1-induced COX-2 regulates liver inflammatory injury via hepatocytes-Kupffer cells (KCs) crosstalk remains unclear and requires further elucidation. Here, we established a COX-2 upregulated model with AFB1 treatment in vivo (C57BL/6 mice, 1 mg/kg body weight, i.g, 4 weeks) and in vitro (human liver HepaRG cells, 1 µM for 24 h). In vivo, AFB1-treated mice exhibited NLRP3 inflammasome activation, inflammatory infiltration, and increased recruitment of KCs. In vitro, dephosphorylated COX-2 by protein phosphatase 2A (PP2A)-B55δ promoted NLRP3 inflammasome activation, including mitochondrial translocation of NLRP3, caspase 1 cleavage, and IL-1ß release. Moreover, phosphorylated COX-2 at serine 601 (p-COX-2Ser601) underwent endoplasmic reticulum (ER) retention for proteasome degradation. Furthermore, pyroptosis and inflammatory response induced by AFB1 were relieved with COX-2 genetic (siPTGS2) intervention or pharmaceutic (celecoxib, 30 mg/kg body weight, i.g, 4 weeks) inhibition of COX-2 via NLRP3 inflammasome suppression in vivo and in vitro. Ex vivo, in a co-culture system with murine primary hepatocytes and KCs, activated KCs induced by damaged signals from pyroptotic hepatocytes, formed a feedback loop to amplify NLRP3-dependent pyroptosis of hepatocytes via pro-inflammatory signaling, leading to liver inflammatory injury. Taken together, our data suggest a novel mechanism that protein quality control of COX-2 determines the intracellular distribution and activation of NLRP3 inflammasome, which promotes liver inflammatory injury via hepatocytes-KCs crosstalk.

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