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1.
Chemosphere ; 238: 124648, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524610

RESUMO

Deoxynivalenol (DON) is one of the most globally prevalent mycotoxins mainly produced by Fusarium species. It can cause pollution to water environmental quality due to its water solubility. Therefore, it is necessary to develop a green and efficient detoxification technology for DON. More importantly, the toxicity of the degradation products should be assessed. Photocatalytic degradation technology has attracted increasing attention in the field of pollutants treatment, especially for wastewater treatment. Herein, the as-prepared NaYF4:Yb,Tm@TiO2 composite (UCNP@TiO2) was employed as a novel photocatalyst for the NIR-enhanced photocatalytic degradation of DON. Three intermediate products were identified by using the ESI/MS analysis and secondary mass spectrogram, with the m/z values of 329.399, 311.243 and 280.913, respectively. Furthermore, the in vitro safety of the product mixtures with various degradation time (30 min, 60 min, 90 min and 120 min) were evaluated through the influences on cell viability, cell morphology, cell cycle, intracellular reactive oxygen species (ROS) level, cell apoptosis and antioxidant capacity of HepG2 cells. There were no significant differences in these investigated indicators between the control (free of DON) and 120 min products treatment. Overall, the results indicated that the toxicity of degradation products after 120 min irradiation was much lower and even nontoxic than that of DON.

2.
J Neurosci Res ; 98(1): 155-167, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31257634

RESUMO

Neurosurgical procedures result in surgically induced brain injury (SBI) that causes postoperative complications including brain edema and neuronal apoptosis in the surrounding brain tissue. SBI leads to the release of cytokines that indirectly cause the stimulation of kynurenine 3-monooxygenase (KMO) and the release of neurotoxic quinolinic acid (QUIN). This study tested a KMO inhibitor, RO 61-8048, to prevent postoperative brain edema and consequent neuronal apoptosis in an in vivo model of SBI. A rodent model of SBI was utilized which involves partial resection of the right frontal lobe. A total of 127 Sprague-Dawley male rats (weight 275-325 g) were randomly divided into the following groups: Sham surgical group, SBI, SBI + DMSO, SBI + RO 61-8048 (10 mg/kg), SBI + RO 61-8048 (40 mg/kg), and SBI + RO 61-8048 (40 mg/kg) + KAT II inhibitor PF-04859989 (5 mg/kg). RO 61-8048 was administered by intraperitoneal injection after SBI. Postoperative assessment at different time points included brain water content (brain edema), neurological scoring, and western blot. SBI increased brain water content (ipsilateral frontal lobe), decreased neurological function, and increased apoptotic markers compared with sham animals. Treatment with RO 61-8048 (40 mg/kg) reduced brain water content and improved long-term neurological function after SBI. RO 61-8048 increased the expression of kynurenic acid while reducing QUIN and apoptotic markers in the surrounding brain tissue after SBI. These neuroprotective effects were reversed by PF-04859989. This study suggests KMO inhibition via RO 61-8048 as a potential postoperative therapy following neurosurgical procedures.

3.
Water Res ; 168: 115099, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604174

RESUMO

Cow manure (CM) was added to a dynamic membrane bioreactor (DMBR) operated under anaerobic condition for enhancing food waste (FW) digestion for over 300 days with stepwise increase of organic loading rates (OLRs) from 1.07 to 11.9 g COD/L/day. At a FW/CM ratio of 3.5:1 (based on volatile solids), the mixed liquor pH was always above 8.0 and no apparent volatile fatty acids (VFAs) accumulation occurred even at the highest OLR of 11.9 g COD/L/day (hydraulic retention time as 10 days and solid retention time as 15.5 days, correspondingly), indicating a very stable operation condition which resulted in an average CH4 yield as high as 250 mL/g COD and CH4 production as high as 2.71 L CH4/L/day. The hardly biodegradable organic components, such as cellulose, hemicellulose, and lignin, were effectively degraded by 78.3%, 58.8%, and 47.5%, respectively. Significantly high anaerobic digestion reaction ratios, especially the hydrolysis ratio which is usually the limiting factor, were calculated based on experimental results. Furthermore, the high lignocellulase contents and coenzyme F420 levels, along with the decrease of cellulose crystallinity from 72.6% to 16.4% in the feedstock, provided strong evidence of an enhanced biological activity by CM addition. By high-throughput sequencing analysis, more abundant and diverse bacterial, archaeal, and fungal genera were identified from the DMBR sludge. With CM addition, the biodegradation of lignocellulose might have produced sufficient H2 and CO2 for the hydrogenotrophic methanogens such as Methanoculleus, Methanomassiliicoccus, and Methanobacterium, which were highly tolerant to ammonium inhibition, and then the elevated ammonium level would have provided high buffering capacity in the DMBR thus ensuring a stable condition for high rate FW digestion and CH4 production.


Assuntos
Microbiota , Eliminação de Resíduos , Anaerobiose , Animais , Biocombustíveis , Reatores Biológicos , Bovinos , Feminino , Alimentos , Esterco , Metano
4.
Physiol Biochem Zool ; 93(1): 13-22, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31657971

RESUMO

The surface area (SA) theory proposes that resting metabolic rate (RMR) scales with body mass, which parallels the exchange SA of organisms, and that a species with a larger scaling exponent of exchange SA has a larger scaling exponent of RMR. However, the effects of exchange SA on metabolic scaling may be eclipsed because oxygen transfer across the respiratory surface is determined not only by the exchange SA but also by ventilation. We hypothesize that the scaling of both gill surface area (GSA) and ventilation frequency (VF) positively affects the scaling of metabolic rate. In six closely related species of carp maintained under the same experimental conditions, the scaling exponents of RMR and GSA were analyzed. In the goldfish, RMR scaled with body mass by an exponent significantly lower than that of GSA but not different from the exponents of GSA in the remaining five species. The scaling exponent of RMR was positively related to those of both GSA and VF among the species. In addition, the VF-corrected metabolic scaling exponent was positively related to the scaling exponent of GSA among the species. These results suggest that variations in GSA scaling and in VF scaling among species mutually affect metabolic scaling.

5.
Mater Sci Eng C Mater Biol Appl ; 107: 110311, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761197

RESUMO

In this study, a small-diameter, double-layered eggshell membrane/thermoplastic polyurethane (ESM/TPU) vascular graft with a wavy structure was developed. The avian eggshell membrane, a fibrous structure similar to the extracellular matrix (ECM), has the potential to yield rapid endothelialization in vitro. The dopamine and heparin modification of the ESM surface not only promoted human umbilical vein endothelial cell (HUVEC) proliferation via cytocompatibility assessment, but also improved its anticoagulation properties as verified in platelet adhesion tests. The biomimetic mechanical properties of the vascular graft were provided by the elastic TPU fibers via electrospinning using a wavy cross-section rotating collector. The advantage of combining these two materials is to make use of the bioactivity of ESM as the internal membrane and the tunable mechanical properties of TPU as the external layer. The circumferentially wavy structure of the vascular graft produced a toe region in the non-linear section of the stress-strain curve similar to that of natural blood vessels. The ESM/TPU graft's circumferential ultimate strength was 2.57 MPa, its strain was 339% mm/mm, and its toe region was found to be around 20% mm/mm. Cyclical tension tests showed that the vascular graft could maintain good mechanical properties and showed no structural damage under repeated extension tests.

6.
Mater Sci Eng C Mater Biol Appl ; 107: 110212, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761208

RESUMO

A critical challenge to the development of tissue engineering small-diameter vascular grafts is to achieve rapid endothelialization and long-term anticoagulation. It is necessary to graft both adhesion and antithrombus factors onto the surface of polycaprolactone without burst release to promote endothelial cell affinity and antithrombogenicity. A bionic structure with a nanocoating that allows a biologically responsive, long-term release was employed in this work to enable the grafting of various bioactive molecules such as gelatin, polylysine, and heparin. This approach involved orienting the biomimetic vascular structures; the self-assembly grafting of gelatin, polylysine, and heparin nanoparticles; and genipin crosslinking to form a multiphase crosslinked nanocoating. In this biologically inspired design, vascular endothelialization and long-term anticoagulation were successfully induced through a matrix metallopeptidase 2 regulative mechanism by delivering both adhesion and antithrombus factors with a responsive, long-term release without burst release. The method provided a simple and effective approach for delivering dual factors for tissue engineering small-diameter vascular grafts.

7.
FASEB J ; : fj201901149RR, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718280

RESUMO

Reactive oxygen species (ROS) generation and mitochondrial dysfunction are related to neuron loss in multiple sclerosis (MS). Although peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) appears to play a key role in modulating levels of mitochondrial ROS, antioxidants, and uncoupling proteins (UCPs), and PGC-1α expression is reduced in the neocortex of patients with MS, it is unclear what its role is in neurons and in the manifestation of clinical symptoms of MS. Here, we show in wild-type (WT) experimental autoimmune encephalomyelitis (EAE) mice that PGC-1α is decreased 13 d after EAE induction followed by a steady decline up to 20 d. These changes were accompanied by parallel alterations in levels of superoxide dismutase 2, peroxiredoxin 3, thioredoxin 2, UCP4, and UCP5. In transgenic (TG) mice with neuron-specific overexpression of PGC-1α (PGC-1αf/fEno2-Cre), clinical symptoms after EAE induction were delayed and less severe than in WT mice. The degrees of apoptotic neuron loss and demyelination were also less severe in PGC-1α-TG mice. Overexpression of PGC-1α in neuronal neuroblastoma spinal cord 34 cells subjected to EAE inflammatory conditions showed similar results to those obtained in vivo. RNA sequencing analysis showed that apoptotic processes were significantly enriched in the top 10 significant gene ontology (GO) terms of differentially expressed genes, and the apoptotic pathway was significantly enriched in Kyoto Encyclopedia of Genes and Genomes pathway analysis. Our findings indicate that up-regulation of neuronal PGC-1α protected neurons from apoptosis in EAE. Manipulating PGC-1α levels in MS may help stave off this devastating disease.-Dang, C., Han, B., Li, Q., Han, R., Hao, J. Up-regulation of PGC-1α in neurons protects against experimental autoimmune encephalomyelitis.

8.
J Exp Clin Cancer Res ; 38(1): 447, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684985

RESUMO

Molecular targeted therapy for advanced hepatocellular carcinoma (HCC) has changed markedly. Although sorafenib was used in clinical practice as the first molecular targeted agent in 2007, the SHARPE and Asian-Pacific trials demonstrated that sorafenib only improved overall survival (OS) by approximately 3 months in patients with advanced HCC compared with placebo. Molecular targeted agents were developed during the 10-year period from 2007 to 2016, but every test of these agents from phase II or phase III clinical trial failed due to a low response rate and high toxicity. In the 2 years after, 2017 through 2018, four successful novel drugs emerged from clinical trials for clinical use. As recommended by updated Barcelona Clinical Liver cancer (BCLC) treatment algorithms, lenvatinib is now feasible as an alternative to sorafenib as a first-line treatment for advanced HCC. Regorafenib, cabozantinib, and ramucirumab are appropriate supplements for sorafenib as second-line treatment for patients with advanced HCC who are resistant, show progression or do not tolerate sorafenib. In addition, with promising outcomes in phase II trials, immune PD-1/PD-L1 checkpoint inhibitors nivolumab and pembrolizumab have been applied for HCC treatment. Despite phase III trials for nivolumab and pembrolizumab, the primary endpoints of improved OS were not statistically significant, immune PD-1/PD-L1 checkpoint therapy remains to be further investigated. This review summarizes the development and progression of molecular targeted and immune-based checkpoint therapies in HCC.

9.
Drug Metab Dispos ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699809

RESUMO

Human liver microsomes (HLM) and S9 fractions (HLS9) are commonly used to study drug metabolism in vitro. However, a quantitative comparison of HLM and HLS9 proteomes is lacking, resulting in the arbitrary selection of one hepatic preparation over another and in difficulties with data interpretation. In this study, we applied a label-free global absolute quantitative proteomics method to the analysis of HLS9 and the corresponding HLM prepared from 102 individual human livers. A total of 3,137 proteins were absolutely quantified, and 3,087 of those were determined in both HLM and HLS9. Protein concentrations were highly correlated between the two hepatic preparations (R=0.87, P<0.0001). We reported the concentrations of 98 drug-metabolizing enzymes (DMEs) and 51 transporters, and demonstrated significant differences between their abundances in HLM and HLS9. We also revealed the protein-protein correlations among these DMEs and transporters and the sex effect on the HLM and HLS9 proteomes. Additionally, HLM and HLS9 displayed distinct expression patterns for protein markers of cytosol and various cellular organelles. Moreover, we evaluated the interindividual variability of three housekeeping proteins, and identified five proteins with low variation across individuals that have the potential to serve as new internal controls for Western blot experiments. In sum, these results will lead to a better understanding of data obtained from HLM and HLS9 and assist in in vitro-in vivo extrapolations. Knowing the differences between HLM and HLS9 also allows us to make a better-informed decision when choosing between these two hepatic preparations for an in vitro drug metabolism study. SIGNIFICANCE STATEMENT: This investigation revealed significant differences in protein concentrations of numerous drug-metabolizing enzymes and transporters between human liver microsomes and S9 fractions. The study also determined the protein-protein correlations among the drug-metabolizing enzymes and transporters and the sex effect on the proteomes of these two hepatic preparations. The results will help interpret data obtained from these two hepatic preparations and also allow us to make a more informed decision when choosing between human liver microsomes and S9 fractions for an in vitro drug metabolism study.

10.
PLoS One ; 14(11): e0223847, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31703074

RESUMO

Plants harbor diverse bacterial communities, which play crucial roles in plant health and growth, in their rhizosphere, phyllosphere and endosphere. Tomato is an important model for studying plant-microbe interactions, but comparison of its associated bacterial community is still lacking. In this study, using Illumina sequencing of 16S rRNA amplicons, we characterized and compared the bacterial size and community from rootzone soil as well as the rhizosphere, phyllosphere and endosphere of roots, stems, leaves, fruits and seeds of tomato plants that were grown in greenhouse conditions. Habitat (soil, phyllospheric, and endophytic) structured the community. The bacterial communities from the soil-type samples (rootzone soil and rhizosphere) showed the highest richness and diversity. The lowest bacterial diversity occurred in the phyllospheric samples, while the lowest richness occurred in the endosphere. Among the endophytic samples, both bacterial diversity and richness varied in different tissues, with the highest values in roots. The most abundant phyla in the tomato-associated community was Proteobacteria, with the exception of the seeds and jelly, where both Proteobacteria and Firmicutes were dominant. At the genus level, the sequences of Pseudomonas and Acinetobacter were prevalent in the rhizosphere, and in the phyllosphere, more than 97% of the sequences were assigned to Acinetobacter. For the endophytes, Acinetobacter, Enterobacter, and Pseudomonas were the abundant genera in the roots, stems and leaves. In the fruits, the bacterial endophytes varied in different compartments, with Enterobacter being enriched in the pericarp and seeds, Acinetobacter in the placenta, and Weissella in the jelly. The present data provide a comprehensive description of the tomato-associated bacterial community and will be useful for better understanding plant-microbe interactions and selecting suitable bacterial taxa for tomato production.

11.
Bosn J Basic Med Sci ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733641

RESUMO

Metastasis associated lung adenocarcinoma transcript 1 (MALAT1) is a highly conserved long noncoding RNA, which has been related to various pathological processes, including cancer. The role and mechanism of MALAT1 in colon cancer are not clear. We investigated MALAT1 expression in colon cancer tissues, the effect of MALAT1 on proliferation and apoptosis of SW480 cells, and the signaling pathway involved in the MALAT1 effects. MALAT1 expression was determined in 60 colon cancer and para-carcinoma tissues using reverse transcription polymerase chain reaction (RT-PCR). Knockdown of MALAT1 in SW480 cells was induced by small interfering RNA (siRNA), and the cells were divided into three groups: untreated control, nonsense siRNA-treated control, and MALAT1 siRNA-treated group. SW480 cell apoptosis was assessed using TUNEL assay and flow cytometry. Apoptosis-related and Wnt/ß-catenin signaling pathway-related proteins were detected by Western blotting in SW480 cells. SW480 cell proliferation was assessed by CCK-8 assay. MALAT1 expression was significantly higher in colon cancer vs. para-carcinoma tissues. Knockdown of MALAT1 by siRNA increased the number of apoptotic cells and the apoptosis rate at 24 h post-transfection in SW480 cells. Bcl2 associated X protein (Bax) expression was increased, B-cell lymphoma 2 (Bcl-2) expression was decreased, and the ratio of cleaved caspase-3 to truncated caspase-3 was increased in MALAT1 siRNA-transfected SW480 cells. MALAT1 knockdown decreased the proliferation of SW480 cells at 24 h, 48 h, and 72 h post-transfection. Wnt and ß-catenin expression was inhibited in MALAT1 siRNA-transfected SW480 cells. Inhibition of MALAT1 expression in colon cancer may promote apoptosis and hinder cell proliferation by suppressing the activation of Wnt/ß-catenin signaling pathway.

12.
BMC Public Health ; 19(1): 1460, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694609

RESUMO

BACKGROUND: Monitoring inequalities in chronic disease prevalence and their preventive care can help build effective strategies to improve health equality. Using hypertension and diabetes as a model, this study measures and decomposes socioeconomic inequalities in their prevalence and preventive care among Chinese adults aged 45 years and older in Shaanxi Province, an underdeveloped western region of China. METHODS: Data of 27,728 respondents aged 45 years and older who participated in the fifth National Health Services Survey conducted in 2013 in Shaanxi Province were analyzed. The relative indexes of inequalities based on Poisson regressions were used to assess disparities in the prevalence of hypertension and diabetes and their preventive care between those with the lowest and the highest socioeconomic status, and the concentration index was used to measure the magnitude of the socioeconomic-related inequality across the entire socioeconomic spectrum. The contribution of each factor to the inequality was further estimated via the concentration index decomposition. RESULTS: Our results indicate a higher prevalence of hypertension and diabetes among the rich than the poor individuals aged 45 years and older in Shaanxi Province, China. Among individuals with hypertension or diabetes, significant inequalities favoring the rich were observed in the use of preventive care, i.e. in adequate use of medication and of blood pressure/blood glucose monitoring. Furthermore, economic status, educational level, employment status, and urban-rural areas were identified as the key socioeconomic indicators for monitoring the inequalities in the patient preventive care. CONCLUSIONS: Our study suggests that the existence of clear inequities in the prevalence of chronic diseases and preventive care among adults aged 45 and older in Shaanxi Province, China. These inequalities in chronic diseases could be as much a cause as a consequence of socioeconomic inequalities.

13.
Int J Biol Macromol ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31751695

RESUMO

Hydroxypropyl methylcellulose (HPMC) / sodium citrate (SC) / lipid tea polyphenol (LTP) photophobic films with different pore sizes from micron scale to nanometer scale were prepared by regulating the SC content (1%-7%). The microstructures, physical and sustained antioxidant properties of these films were studied by using wide angel X-ray diffraction, small angle X-ray scattering (SAXS), scanning electron microscope, whiteness meter, ultraviolet spectrophotometer, texture analyzer and peroxide value test. Composite films with higher SC content showed larger pore size and whiteness. With the increasing SC content, crystallinity first increased then decreased. The addition of SC decreased the Ds (surface fractal dimension) value, smoothness of the cross-section structure, tensile strength, elongation and modulus of composite films. HPMC/SC/LTP microporous films possessed control-release property in oil system, reflected by the lowest peroxide value of peanut oil enclosed in film with 3% SC during three weeks, meaning this film showed the best sustained antioxidant property.

14.
Nanotechnology ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31751987

RESUMO

The ability of ZnO photodetectors to absorb UV light plays a key role in enhancing responsivity and performance in electronic, optical, and photonic devices. Herein, the light trapping effect of ZnO is used to design and fabricate a novel honeycomb-like ZnO nanomaterial-based UV photodetector with an excellent photoelectric performance. Compared with the traditional ZnO film UV photodetector, the photoresponsivity of the film with honeycomb nanomaterials can reach up to 4.79 A W-1, which is an improvement of about 300 times. In addition, the honeycomb ZnO nanomaterials UV photodetectors exhibit an improved light absorption, a very photo-to-dark current ratio (2.46 × 103), and an excellent detectivity (4.61 × 1012 Jones). The ZnO honeycomb nanostructure synthesized in this work exhibits a strong trapping effect, providing new insights into the research of nanomaterials used for UV photodetectors.

15.
Viruses ; 11(11)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752179

RESUMO

Foot and mouth disease (FMD) endemicity in Ethiopia's livestock remains an ongoing cause for economic concern, with new topotypes still arising even in previously unaffected areas. FMD outbreaks occur every year almost throughout the country. Understanding the outbreak dynamics, endemic serotypes, and lineage profiles of FMD in this country is very critical in designing control and prevention programs. For this, detailed information on outbreak dynamics in Ethiopia needs to be understood clearly. In this article, therefore, we review the spatial and temporal patterns and dynamics of FMD outbreaks from 2008 to 2018. The circulating serotypes and the topotypic profiles of the virus are also discussed. FMD outbreak data were obtained from; reports of MoARD (Ministry of Agriculture and Rural Development)/MoLF (Ministry of livestock and Fishery, NVI (National Veterinary Institute), and NAHDIC (National Animal Health Diagnostic and Investigation Center); published articles; MSc works; PhD theses; and documents from international organizations. To effectively control and prevent FMD outbreaks, animal health agencies should focus on building surveillance systems that can quickly identify and control ongoing outbreaks and implement efficient preventive measures.

16.
Molecules ; 24(22)2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31752282

RESUMO

To discover novel potent cytotoxic diterpenoids, a series of hybrids of dehydroabietic acid containing 1,2,3-triazole moiety were designed and synthesized. The target compounds were characterized by means of FT-IR, 1H NMR, 13C NMR, ESI-MS and elemental analysis techniques. The in vitro cytotoxicity of these compounds was evaluated by standard MTT (methyl thiazolytetrazolium) assay against CNE-2 (nasopharynx), HepG2 (liver), HeLa (epithelial cervical), BEL-7402 (liver) human carcinoma cell lines and human normal liver cell (HL-7702). The screening results revealed that most of the hybrids showed significantly improved cytotoxicity over parent compound DHAA. Among them, [1-(3-fluorobenzyl)-1H-1,2,3-triazole-4-yl]dehydroabietic acid methyl ester (3c), and [1-(2-nitrobenzyl)-1H-1,2,3-triazole-4-yl]dehydroabietic acid methyl ester (3k) displayed better antiproliferative activity with IC50 (50% inhibitory concentration) values of 5.90 ± 0.41 and 6.25 ± 0.37 µM toward HepG2 cells compared to cisplatin, while they exhibited lower cytotoxicity against HL-7702. Therefore, the 1,2,3-triazole-hybrids could be a promising strategy for the synthesis of antitumor diterpenoids and it also proved the essential role of 1,2,3-triazole moiety of DHAA in the biological activity.

17.
Exp Cell Res ; : 111745, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31765611

RESUMO

Orthodontic tooth movement (OTM) is initiated by mechanical force and featured as alveolar bone remodeling. Periodontal ligament cells (PDLCs) are one of the major cell components in periodontium and responsible for the signal transduction during OTM. Up to now, the mechanical stress-induced genetic alteration and mechanotransduction mechanisms in PDLCs still remain not fully understood. In this study, we identified a novel compressive force responsive gene-Growth differentiation factor 15 (GDF15), whose expression transcriptionally increased in human periodontal ligament cells (PDLCs) after exposure to the static compressive force in vitro. Functional analyses proved that GDF15 could promote osteoclast differentiation of the murine macrophage cell line RAW264.7 cells. Molecular investigation uncovered that GDF15 could promote the expression of several pro-inflammatory cytokines and RANKL/OPG ratio in PDLCs, while knockdown of GDF15 impaired their upregulation induced by compressive force. Additionally, administration of recombinant GDF15 protein stimulated the M1-like polarization of RAW264.7 cells and THP-1 induced macrophages. Mechanistically, siRNA-mediated suppression of GDF15 significantly disrupted the nuclear translocation of NF-κB and ERK phosphorylation in response to compressive force. Finally, Yes-associated protein (YAP) was demonstrated to be the upstream regulator of GDF15 in human PDLCs, implying a force-induced YAP-GDF15 regulation mechanism. Overall, these data suggested important roles of GDF15 in the functional modulation of both PDLCs and osteoclast progenitors in response to compressive force, providing novel insights into the molecular mechanism of mechanotransduction during OTM process.

18.
Nanotechnology ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31766044

RESUMO

Fabricating large-scale nanoarrays is a significant and challenging work in the field of nanometer devices. Anodic aluminum oxide (AAO) membrane is considered as a promising mask due to its inherent advantages such as low-cost and tunable pore diameter. However, there are few reports on the use of non-through-hole large-area AAO membrane as a mask. Due to its higher mechanical strength, non-through-hole AAO membrane has the advantage of self-supporting for large-area fabrication. Herein, we present a robust approach to transferring nanopattern to substrates with high fidelity by using the non-through-hole AAO membrane as an etching mask. A novel two-step inductively coupled plasma (ICP) etching method is adopted. The morphological evolution of the AAO during ICP etching is systematically investigated. The aspect ratio of the AAO can be quantitatively controlled by adjusting etching time. The AAO nanopore arrays with an area of 7.1 cm2 are successfully transferred to gallium nitride wafer to enhance photoluminescence. The luminous intensity of the nano-array LED with a pore diameter of 400 nm and a depth of 150 nm is improved by 3.4 times compared with the LED without the nano-array. This method extends the opportunities for AAO mask to serve as generic templates for novel applications that are previously impractical due to the difficulty of large-scale nano-pattern transfer.

19.
Int J Mol Sci ; 20(23)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766739

RESUMO

Chrysanthemum (Chrysanthemum morifolium (Ramat.) Kitamura) plants have great ornamental value, but their flowers can also be a source of pollen contamination. Previously, morphological and cytological studies have shown that anthers of some chrysanthemum cultivars such as 'Qx-115' fail to dehisce, although the underlying mechanism is largely unknown. In this study, we investigated the molecular basis of anther indehiscence in chrysanthemum via transcriptome analysis of a dehiscent cultivar ('Qx-097') and an indehiscent cultivar ('Qx-115'). We also measured related physiological indicators during and preceding the period of anther dehiscence. Our results showed a difference in pectinase accumulation and activity between the two cultivars during dehiscence. Detection of de-esterified pectin and highly esterified pectin in anthers during the period preceding anther dehiscence using LM19 and LM20 monoclonal antibodies showed that both forms of pectin were absent in the stomium region of 'Qx-097' anthers but were abundant in that of 'Qx-115' anthers. Analysis of transcriptome data revealed a significant difference in the expression levels of two transcription factor-encoding genes, CmLOB27 and CmERF72, between 'Qx-097' and 'Qx-115' during anther development. Transient overexpression of CmLOB27 and CmERF72 separately in tobacco leaves promoted pectinase biosynthesis. We conclude that CmLOB27 and CmERF72 are involved in the synthesis of pectinase, which promotes the degradation of pectin. Our results lay a foundation for further investigation of the role of CmLOB27 and CmERF72 transcription factors in the process of anther dehiscence in chrysanthemum.

20.
J Agric Food Chem ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31707781

RESUMO

Dietary interventions alter the formation of the disease-associated metabolite, trimethylamine (TMA), via intestinal microbial TMA lyase activity. Nevertheless, the mechanisms regulating microbial enzyme production are still unclear. Sequencing of the gut bacteria 16S rDNA demonstrated that dietary intervention changed the composition of the gut microbiota and the functional metagenome involved in the choline utilization pathway. Characterization of the functional profile of the metagenomes and metabonomics analysis revealed that a series of Kyoto Encyclopedia of Genes and Genomes orthologous groups and enzyme groups related to accumulation of methylglyoxal (MG) and glycine were enriched in red meat diet-fed animals, whereas fiber-rich diet suppressed glycine formation via the MG-dependent pathway. Our observations suggest associations between choline-TMA lyase expression and MG formation, which are indicative of a novel role of the gut microbiota in choline metabolism and highlight it as a potential target for inhibiting TMA production.

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