Exploring the oncogenic potential of circSOD2 in clear cell renal cell carcinoma: a novel positive feedback loop.

BACKGROUND: Existing studies have found that circular RNAs (circRNAs) act as sponges for micro RNAs (miRNAs) to control downstream genes. However, the specific functionalities and mechanisms of circRNAs in human clear cell renal cell carcinoma (ccRCC) have yet to be thoroughly investigated. METHODS: Patient cohorts from online databases were used to screen candidate circRNAs, while another cohort from our hospital was obtained for validation. CircSOD2 was identified as a potential oncogenic target, and its relevant characteristics were investigated during ccRCC progression through various assays. A positive feedback loop containing downstream miRNA and its target gene were identified using bioinformatics and validated by luciferase reporter assays, RNA pull-down, and high-throughput sequencing. RESULTS: CircSOD2 expression was elevated in tumor samples and significantly correlated with overall survival (OS) and the tumor stage of ccRCC patients, which appeared in the enhanced proliferation, invasion, and migration of tumor cells. Through competitive binding to circSOD2, miR-532-3p can promote the expression of PAX5 and the progression of ccRCC, and such regulation can be salvaged by miR-532-3p inhibitor. CONCLUSION: A novel positive feedback loop, PAX5/circSOD2/miR-532-3p/PAX5 was identified in the study, indicating that the loop may play an important role in the diagnosis and prognostic prediction in ccRCC patients.

Total flavonoids of Broussonetia papyrifera alleviate non-alcohol fatty liver disease via regulating Nrf2/AMPK/mTOR signaling pathways.

BACKGROUNDS: Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent chronic liver diseases. The leaves of Broussonetia papyrifera contain a large number of flavonoids, which have a variety of biological functions. METHODS: In vitro experiments, free fatty acids were used to stimulate HepG2 cells. NAFLD model was established in vivo in mice fed with high fat diet (HFD) or intraperitoneally injected with Tyloxapol (Ty). At the same time, Total flavonoids of Broussonetia papyrifera (TFBP) was used to interfere with HepG2 cells or mice. RESULTS: The results showed that TFBP significantly decreased the lipid accumulation induced by oil acid (OA) with palmitic acid (PA) in HepG2 cells. TFBP decreased the total cholesterol (TC), the triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and increased high-density lipoprotein cholesterol (HDLC) in serum. TFBP could also effectively inhibit the generation of reactive oxygen species (ROS) and restrained the level of myeloperoxidase (MPO), and enhance the activity of superoxide dismutase (SOD) to alleviate the injury from oxidative stress in the liver. Additionally, TFBP activated nuclear factor erythroid-2-related factor 2 (Nrf2) pathway to increasing the phosphorylation of AMP-activated protein kinase (AMPK). Meanwhile, protein levels of mTORC signaling pathway were evidently restrained with the treatment of TFBP. CONCLUSION: Our experiments proved that TFBP has the therapeutic effect in NAFLD, and the activation of Nrf2 and AMPK signaling pathways should make sense.

LRP1 induces anti-PD-1 resistance by modulating the DLL4-NOTCH2-CCL2 axis and redirecting M2-like macrophage polarisation in bladder cancer.

The tumour microenvironment (TME) drives bladder cancer (BLCA) progression. Targeting the TME has emerged as a promising strategy for BLCA treatment in recent years. Furthermore, checkpoint blockade therapies are only beneficial for a minority of patients with BLCA, and drug resistance is a barrier to achieving significant clinical effects of anti-programmed cell death protein-1 (PD-1)/programmed death protein ligand-1 (PD-L1) therapy. In this study, higher low-density lipoprotein receptor-related protein 1 (LRP1) levels were related to a poorer prognosis for patients with various cancers, including those with higher grades and later stages of BLCA. Enrichment analysis demonstrated that LRP1 plays a role in the epithelial-mesenchymal transition (EMT), NOTCH signalling pathway, and ubiquitination. LRP1 knockdown in BLCA cells delayed BLCA progression both in vivo and in vitro. Furthermore, LRP1 knockdown suppressed EMT, reduced DLL4-NOTCH2 signalling activity, and downregulated M2-like macrophage polarisation. Patients with BLCA and higher LRP1 levels responded weakly to anti-PD-1 therapy in the IMvigor210 cohort. Moreover, LRP1 knockdown enhanced the therapeutic effects of anti-PD-1 in mice. Taken together, our findings suggest that LRP1 is a potential target for improving the efficacy of anti-PD-1/PD-L1 therapy by preventing EMT and M2-like macrophage polarisation by blocking the DLL4-NOTCH2 axis.

Adventitious root culture of Lessertia frutescens for the production of triterpenoid saponins and polysaccharides.

Lessertia frutescens is a perennial shrub of commercial importance in South Africa, but the scarcity of plant resources has limited current product production. In this study, to provide an alternative approach for obtaining L. frutescens material, adventitious roots (ARs) were induced from sterilized seedlings and cultured in a suspension culture system. During this process, selection tests were conducted to find a suitable auxin and its concentration for AR induction and a suitable basal medium for AR growth and metabolite accumulation; a kinetic study was then performed to constructure kinetic models. The results showed that compared to other auxins and concentrations, indole-3-butyric acid at 3 mg/L was suitable for increasing the number and length of ARs during AR induction. In AR suspension culture, Schenk and Hildebrandt (SH) was better than other basal media, and the maximum AR fresh (86.9 g/L) or dry weight (5.5 g/L), total triterpenoid saponin (92.6 mg/g DW), and polysaccharide (114.7 mg/g DW) contents were determined in the 1.5×SH medium. In addition, AR biomass and metabolite contents reached the maximum on day 42. The kinetic models for AR growth and triterpenoid and polysaccharide production were constructed, providing the basis for further optimization of culture conditions and large-scale culture.

Improving Flavonoid Accumulation of Bioreactor-Cultured Adventitious Roots in Oplopanax elatus Using Yeast Extract.

Oplopanax elatus is an endangered medicinal plant, and adventitious root (AR) culture is an effective way to obtain its raw materials. Yeast extract (YE) is a lower-price elicitor and can efficiently promote metabolite synthesis. In this study, the bioreactor-cultured O. elatus ARs were treated with YE in a suspension culture system to investigate the elicitation effect of YE on flavonoid accumulation, serving for further industrial production. Among YE concentrations (25-250 mg/L), 100 mg/L YE was the most suitable for increasing the flavonoid accumulation. The ARs with various ages (35-, 40-, and 45-day-old) responded differently to YE stimulation, where the highest flavonoid accumulation was found when 35-day-old ARs were treated with 100 mg/L YE. After YE treatment, the flavonoid content increased, peaked at 4 days, and then decreased. By comparison, the flavonoid content and antioxidant activities in the YE group were obviously higher than those in the control. Subsequently, the flavonoids of ARs were extracted by flash extraction, where the optimized extraction process was: 63% ethanol, 69 s of extraction time, and a 57 mL/g liquid-material ratio. The findings provide a reference for the further industrial production of flavonoid-enriched O. elatus ARs, and the cultured ARs have potential application for the future production of products.

A synthetic lethal approach to drug targeting of G-quadruplexes based on CX-5461.

DNA G-quadruplex (G4) structures are enriched at human genome loci critical for cancer development, such as in oncogene promoters, telomeres, and rDNA. Medicinal chemistry approaches to developing drugs that target G4 structures date back to over 20 years ago. Small-molecule drugs were designed to target and stabilize G4 structures, thereby blocking replication and transcription, resulting in cancer cell death. CX-3543 (Quarfloxin) was the first G4-targeting drug to enter clinical trials in 2005; however, because of the lack of efficacy, it was withdrawn from Phase 2 clinical trials. Efficacy problems also occurred in the clinical trial of patients with advanced hematologic malignancies using CX-5461 (Pidnarulex), another G4-stabilizing drug. Only after the discovery of synthetic lethal (SL) interactions between Pidnarulex and the BRCA1/2-mediated homologous recombination (HR) pathway in 2017, promising clinical efficacy was achieved. In this case, Pidnarulex was used in a clinical trial to treat solid tumors deficient in BRCA2 and PALB2. The history of the development of Pidnarulex highlights the importance of SL in identifying cancer patients responsive to G4-targeting drugs. In order to identify additional cancer patients responsive to Pidnarulex, several genetic interaction screens have been performed with Pidnarulex and other G4-targeting drugs using human cancer cell lines or C. elegans. Screening results confirmed the synthetic lethal interaction between G4 stabilizers and HR genes and also uncovered other novel genetic interactions, including genes in other DNA damage repair pathways and genes in transcription, epigenetic, and RNA processing deficiencies. In addition to patient identification, synthetic lethality is also important for the design of drug combination therapy for G4-targeting drugs in order to achieve better clinical outcomes.

Optimizing elicitation strategy of salicylic acid for flavonoid and phenolic production of fed-batch cultured Oplopanax elatus adventitious roots.

Oplopanax elatus is a valuable medicinal plant, but its plant resource is lacking. Adventitious root (AR) culture of O. elatus is an effective way for the production of plant materials. Salicylic acid (SA) exerts enhancement effect on metabolite synthesis in some plant cell/organ culture systems. To clarify the elicitation effect of SA on fed-batch cultured O. elatus ARs, this study investigated the effects of SA concentration, and elicitation time and duration. Results showed that flavonoid and phenolic contents, and antioxidant enzyme activity obviously increased when the fed-batch cultured ARs were treated with 100 µM SA for 4 days starting on day 35. Under this elicitation condition, total flavonoid and phenolic contents reached 387 rutin mg/g DW and 128 gallic acid mg/g DW, respectively, which were significantly (p < 0.05) higher than those in the SA-untreated control. In addition, DPPH scavenging and ABTS+ scavenging rates, and Fe2+ chelating rate also greatly increased after SA treatment, and their EC50 values were 0.0117, 0.61, and 3.34 mg/L, respectively, indicating the high antioxidant activity. The findings of the present study revealed that SA could be used as an elicitor to improve the flavonoid and phenolic production in fed-batch O. elatus AR culture.

Aescin can alleviate NAFLD through Keap1-Nrf2 by activating antioxidant and autophagy.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic liver disease worldwide. It has been proven that aescin (Aes), a bioactive compound derived from the ripe dried fruit of Aesculus chinensis Bunge, has a number of physiologically active properties like anti-inflammatory and anti-edema, however it has not been investigated as a potential solution for NAFLD. PURPOSE: This study's major goal was to determine whether Aes can treat NAFLD and the mechanism underlying its therapeutic benefits. METHODS: We constructed HepG2 cell models in vitro that were affected by oleic and palmitic acids, as well as in vivo models for acute lipid metabolism disorder caused by tyloxapol and chronic NAFLD caused by high-fat diet. RESULTS: We discovered that Aes could promote autophagy, activate the Nrf2 pathway, and ameliorate lipid accumulation and oxidative stress both in vitro and in vivo. Nevertheless, in Autophagy-related proteins 5 (Atg5) and Nrf2 knockout mice, Aes lost its curative impact on NAFLD. Computer simulations show that Aes might interact with Keap1, which might allow Aes to increase Nrf2 transfer into the nucleus and perform its function. Importantly, Aes's stimulation of autophagy in the liver was hampered in Nrf2 knockout mice. This suggested that the impact of Aes in inducing autophagy may be connected to the Nrf2 pathway. CONCLUSION: We first discovered Aes's regulating effects on liver autophagy and oxidative stress in NAFLD. And we found Aes may combine the Keap1 and regulate autophagy in the liver by affecting Nrf2 activation to exert its protective effect.

Gomphrena globosa L. extract alleviates carbon tetrachoride-induced liver injury in mice by activating antioxidant signaling pathways and promoting autophagy.

BACKGROUND: Carbon tetrachloride (CCl4) is highly toxic to animal liver and is a major contributor to liver injury. Gomphrena globosa L. (GgL) is an edible plant with anti-inflammation and antioxidation properties. The aim of this study was to investigate the potential therapeutic effects of GgL on liver injury. METHODS AND RESULTS: A model of chronic liver injury in mice was established by intraperitoneal injection of CCl4 (0.4 mL/kg) for 3 weeks, and the mice were treated intraperitoneally with different concentrations of GgL crude extract (GgCE; 100, 200, 300 mg/kg) or Bifendatatum (Bif; 20 mg/kg) in the last 2 weeks. The results showed that GgCE treatment alleviated the liver injury, improved the pathological changes caused by CCl4 on the mice liver, and enhance the antioxidant capacity. We also found that GgCE increased the expression of antioxidant stress related proteins, decreased the phosphorylation levels of autophagy related proteins PI3K and mTOR, and decreased the expression of LC3 II and P62 proteins. CONCLUSION: These results suggest that GgCE alleviated CCl4-induced chronic liver injury in mice by activating antioxidant signaling pathways and promoting autophagy, indicating a potential therapeutic effect of GgCE on liver injury.

Phellinus linteus polysaccharides mediates acetaminophen-induced hepatotoxicity via activating AMPK/Nrf2 signaling pathways.

Overdose of acetaminophen (APAP) is currently one of the main causes of hepatoxicity and acute liver injury, which is often linked to oxidative stress. Phellinus linteus polysaccharides (Phps) have shown many hepatoprotective effects, however, the mechanism of Phps on APAP-induced acute liver injury has not been further elucidated. The aim of this study is to investigate the underlying mechanism of Phps to acute liver injury. The expression of AMPK/Nrf2 and autophagy were detected using western blot. The results indicated that Phps treatment effectively alleviated APAP-induced acute liver injury by reducing alanine transaminase (ALT) and aspartate aminotransferase (AST) levels in serum. Phps significantly attenuated myeloperoxidase (MPO) activity and glutathione (GSH) depletion. Meanwhile, Phps remarkably alleviated histopathological changes. Further research found that Phps promoted AMPK pathway and up-regulated nuclear factor erythroid-2-related factor (Nrf2) transported into nucleus, and elevated heme oxygenase 1(HO-1), glutamate-cysteine ligase catalytic (GCLC), glutamate cysteine ligase modifier (GCLM) and quinone oxidoreductase (NQO1). Additionally, Phps apparently facilitated the expression of autophagy proteins (ATG3, ATG5, ATG7, and ATG12). However, the protection of pathologic changes was nearly absent in Nrf2-/- mice. Phps have potential in preventing oxidative stress in APAP-induced acute liver injury.

Enterobacter cloacae aggravates metabolic disease by inducing inflammation and lipid accumulation.

It is well known that gut microbiota imbalance can promote the development of metabolic disease. Enterobacter cloacae (E. cloacae) is a kind of opportunistic pathogen in the intestine. Therefore, we hypothesized that E. cloacae accelerated the development of metabolic disease. To answer this question, we used E. cloacae to induce disease in guinea pigs. We used H&E staining to detect the pathological changes of liver and aorta and used Oil Red O staining to evaluate the lipid accumulation in the liver. And that we used a kit to detect AST content and used Western blot to detect protein levels in the liver. We found that E. cloacae could induce liver pathological changes and lipid accumulation as well as aortic wall pathological changes in guinea pigs. And E. cloacae increased the liver index to 5.94% and the serum AST level to 41.93 U/L. Importantly, E. cloacae activated liver high mobility group protein (HMGB1)/toll-like receptor 4 (TLR4)/myeloiddifferentiationfactor88 (MYD88)/nuclear factor-kappa B (NF-κB) signal and sterol regulatory element-binding protein 1c (SREBP-1c) and inhibited AMP-activated protein kinase (AMPK). We conclude that E. cloacae promote nonalcoholic fatty liver disease (NAFLD) by inducing inflammation and lipid accumulation, and E. cloacae also promote atherosclerosis. These findings are important for study on the pathogenesis and drug screening of NAFLD and atherosclerosis.

Lipopolysaccharide and tyloxapol accelerate the development of atherosclerosis in mice.

The occurrence of atherosclerosis is closely related to inflammation and lipid metabolism disorder. It has been found that lipopolysaccharide (LPS) could induce inflammation, and tyloxapol (Ty) could induce hyperlipidemia. However, the effects of LPS and Ty on the development and mechanism of atherosclerosis have not been investigated thoroughly. To answer this question, we used assay kits to detect total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) content to evaluate dyslipidemia. We used hematoxylin and eosin staining to evaluate the pathological structure of the aorta and liver, and then used Oil Red O staining to access lipid accumulation in the aortic wall. Subsequently, we used the alanine transaminase (ALT) kit to examine the liver injury. Finally, we used the Western blot experiment to measure proteins that regulate lipid metabolism. We found that the LPS + Ty group could increase the levels of TC, TG, and LDL in the serum and promote lipid accumulation in the aortic wall in mice. Moreover, our study showed that the LPS + Ty group induced pathological changes in hepatocytes and increased ALT content in mice. Significantly, we found that the LPS + Ty group could activate acetyl-CoA carboxylase, sterol regulatory element-binding protein-1c, and inhibit peroxisome proliferator-activated receptors α in mice. Therefore, we suppose that LPS and Ty aggravated the development of atherosclerosis by promoting hyperlipidemia and the disorder of lipid metabolism in mice. These findings are significant for the study of the pathogenesis of atherosclerosis and the selection of animal models.

Erythritol Improves Nonalcoholic Fatty Liver Disease by Activating Nrf2 Antioxidant Capacity.

Nonalcoholic fatty liver disease (NAFLD) is a kind of serious fat disorder that has become a critical problem to human society. Therefore, finding drugs that are safe and effective has become more and more important. Erythritol (Ery) is a polyol sweetener with a variety of biological functions. However, whether Ery has a relieving effect on NAFLD has not been reported yet. Therefore, we induced HepG2 cells with oleic acid and palmitic acid as our in vitro model. Moreover, we choose wild-type mice with tyloxapol and high-fat diet and nuclear factor E2-related factor 2 (Nrf2) knockout mice with high-fat diet as our in vivo model. We found that Ery could reverse the lipid accumulation, oxidative stress, and endoplasmic reticulum stress caused by the NAFLD model. The mechanism studies showed that Ery promoted the translocation of Nrf2 from cytoplasm to nucleus, and the molecular simulation docking results of Ery and Nrf2 showed that there was a hydrogen bond between them. Moreover, Ery could promote the production of HO-1 and NQO1 antioxidant proteins and inhibit the expression of endoplasmic reticulum stress proteins GPR78, p-PERK, and CHOP. On the contrast, when Nrf2 was knocked out in mice, Ery lost its protective effect on NAFLD. In conclusion, we found that the potential mechanism of Ery's protective effect is that it plays an antioxidant role by activating the Nrf2 signaling pathway, thereby inhibiting endoplasmic reticulum stress and lipid accumulation in NAFLD.

Gentiopicroside Ameliorates Oxidative Stress and Lipid Accumulation through Nuclear Factor Erythroid 2-Related Factor 2 Activation.

The activation of nuclear factor erythroid 2-related factor 2 (Nrf2) is closely related to the alleviation of nonalcoholic fatty liver disease (NAFLD) by regulating oxidative stress and lipid homeostasis. Gentiopicroside (GPS), an iridoid glycoside found in the Gentianaceae, possesses anti-inflammatory and antioxidant effects. However, the protective effects of GPS on lipid accumulation and oxidative damage have not been investigated thoroughly in free fatty acid- (FFA-) induced HepG2 cells and tyloxapol- (Ty-) induced hyperlipidemia mice. Cell counting kit-8 assays, Oil Red O staining, Western blotting analysis, extraction of nuclear and cytosolic proteins, and biochemical index assay were employed to explore the mechanisms by which GPS exerts a protective effect on FFA-induced HepG2 cells and Ty-induced hyperlipidemia mouse model. This paper demonstrates that GPS could effectively alleviate NAFLD by elevating cell viability, reducing fatty deposition, downregulating TG, and activating nucleus Nrf2 in FFA-induced HepG2 cells. Meanwhile, GPS significantly regulated the activation of phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, Nrf2 antioxidant pathway, peroxisome proliferator-activated receptor α (PPARα), and GPS-inhibited sterol regulatory element-binding protein-1c (SREBP-1c) expression in FFA-stimulated lipid accumulation of HepG2 cells and Ty-treated mice. Interestingly, we highlight that PI3K/AKT inhibitor (LY294002) markedly increased the expression of Nrf2 antioxidant pathway, PPARα, and downregulated SREBP-1c in FFA-stimulated HepG2 cells. For these reasons, we found that the deletion of Nrf2 could lose the protective effects of GPS on the Nrf2 antioxidant pathway and PPARα activation and SREBP-1c inactivation in FFA-stimulated HepG2 cells and Ty-treated mice. GPS treatment had no effect on abnormal lipogenesis and antioxidant enzymes in Ty-induced Nrf2-/- mice. This work gives a new explanation that GPS may be a useful therapeutic strategy for NAFLD through upregulation of the Nrf2 antioxidant pathway, which can alleviate oxidative damage and lipid accumulation.

Graph-based multi-user scheduling for indoor cooperative visible light transmission.

Recent progress in the indoor visible light communication (VLC) has shown promising signs of alleviating an increasing strain on the radio frequency spectrum and enhancing transmission capacity. Nevertheless, the indoor VLC usually suffers from inter-channel interference (ICI) due to the dense light-emitting diode (LED) deployment. The ICI is considered as a key factor affecting signal to interference and noise ratio (SINR) and spectral efficiency. To address this challenge, an efficient multi-user scheduling framework that employs interference coordination and cooperative transmission is investigated based on the graph theory. To effectively mitigate ICI and maximize benefit of the cooperative transmission, the cell-centric (CC) and user-centric (UC) clustering are introduced for cooperative transmission. For the CC clustering, the multi-user scheduling problem under the proportional fairness criterion is formulated to maximize spectral efficiency while ensuring user fairness. Such a problem is solved by linear programming and greedy algorithms after transforming it into a maximum weighted independent set problem with the aid of a modified interference graph. For the UC clustering, the multi-user scheduling problem under the max-min criterion is formulated and solved by a proposed heuristic approach based on the bipartite graph theory. Numerical results show that the proposed graph-based scheduling is capable of providing up to 7.7 dB gain in SINR over the non-cooperative transmission. The bipartite graph scheduling offers high spectral efficiency and service fairness index. In the worst case with an occlusion probability of 1, a small SINR penalty of up to 1 dB is observed with the greedy algorithm. It is shown that the graph-based scheduling is robust to receiver rotation and occlusion in terms of spectral efficiency, SINR, and user fairness.

Geniposide alleviates non-alcohol fatty liver disease via regulating Nrf2/AMPK/mTOR signalling pathways.

Non-alcohol fatty liver disease (NAFLD) is a common disease which causes serious liver damage. Geniposide (GEN), a kind of iridoid glycoside extracted from Gardenia jasminoides fruit, has many biological effects, such as resistance to cell damage and anti-neurodegenerative disorder. Lipid accumulation was obvious in tyloxapol-induced liver and oil acid (OA) with palmitic acid (PA)-induced HepG2 cells compared with the control groups while GEN improved the increasing conditions. GEN significantly lessened the total cholesterol (TC), the triglyceride (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), myeloperoxidase (MPO), reactive oxygen species (ROS) and increased high-density lipoprotein (HDL), superoxide dismutase (SOD) to response the oxidative stress via activating nuclear factor erythroid-2-related factor 2 (Nrf2), haeme oxygenase (HO)-1 and peroxisome proliferator-activated receptor (PPAR)α which may influence the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) signalling pathway in mice and cells. Additionally, GEN evidently decreased the contents of sterol regulatory element-binding proteins (SREBP)-1c, phosphorylation (P)-mechanistic target of rapamycin complex (mTORC), P-S6K, P-S6 and high mobility group protein (HMGB) 1 via inhibiting the expression of phosphoinositide 3-kinase (PI3K), and these were totally abrogated in Nrf2-/- mice. Our study firstly proved the protective effect of GEN on lipid accumulation via enhancing the ability of antioxidative stress and anti-inflammation which were mostly depend on up-regulating the protein expression of Nrf2/HO-1 and AMPK signalling pathways, thereby suppressed the phosphorylation of mTORC and its related protein.

Comparison of interpolation-based sampling frequency offset compensation schemes for practical OFDM-VLC systems.

Sampling frequency offset (SFO) is an important issue in the orthogonal frequency-division multiplexing (OFDM)-based visible light communication (VLC) systems with low-cost analog-to-digital or digital-to-analog converters (ADCs/DACs). A digital interpolation or resampling filter can be used to effectively compensate the SFO. In such case, oversampling at the receiver ADC is required to mitigate the aliasing effect due to imperfect DACs and nonlinearity of visible light sources that cause extra frequency components inside/outside the OFDM signal spectrum. The oversampling factor (rate) is mainly determined by the order of the digital interpolation filter and nonlinear VLC links. The design of the OFDM-VLC receiver incorporating the digital interpolation filter is vital as it affects not only the transmission performance but also the complexity of digital signal processing (DSP). To evaluate the feasibility of the digital interpolation-based SFO compensation schemes for cost-sensitive VLC applications, in this paper, a real-time OFDM-VLC receiver incorporating the 2nd/3rd/4th order interpolation filters is experimentally demonstrated. An OFDM frame structure is designed for the synchronization including SFO estimation and compensation, in which the precision and latency of DSP are considered. On the basis of the real-time OFDM-VLC receiver, the comparison in the VLC transmission performance and DSP complexity between different interpolation-based SFO compensation schemes is discussed.

Chicoric acid ameliorate inflammation and oxidative stress in Lipopolysaccharide and d-galactosamine induced acute liver injury.

Chicoric acid is polyphenol of natural plant and has a variety of bioactivity. Caused by various kinds of stimulating factors, acute liver injury has high fatality rate. The effect of chicoric acid in acute liver injury induced by Lipopolysaccharide (LPS) and d-galactosamine (d-GalN) was investigated in this study. The results showed that CA decreased the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and reduced the mortality induced by LPS/d-GalN. CA can restrain mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) to alleviate inflammation. Meanwhile, the results indicated CA can active nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway with increasing the level of AMP-activated protein kinase (AMPK). And with the treatment of CA, protein levels of autophagy genes were obvious improved. The results of experiments indicate that CA has protective effect in liver injury, and the activation of AMPK and autophagy may make sense.

Real-time investigation of CAP transceivers with hybrid digital equalization for visible light communication.

In a practical light emitted diodes (LEDs)-based visible light communication (VLC) system, high-speed transmission is generally limited by the LED bandwidth. To address the bandwidth limitation, a hybrid digital linear and decision-feedback equalization (DFE) is investigated to improve the transmission performance (or spectral efficiency) in the carrier-less amplitude phase modulation (CAP)-based VLC systems. A real-time CAP-VLC transceiver with the hybrid digital equalization is designed, based on which 200 Mb/s transmission is successfully demonstrated over a 15 m VLC link with the commercial red LEDs (bandwidth: 6.5 MHz). In the real-time CAP-VLC system, the baseline wander (BLW) is observed, due to the removal of the low-frequency components with a direct current (DC) block. The BLW effect can be mitigated by increasing the roll-off factor. However, this roll-off factor affects the equalization performance, due to an increased loss in the signal spectrum beyond the system bandwidth. Optimization of the roll-off factor and filter length is required. Experimental results show that, with the optimized real-time transceiver design, the hybrid Wiener/recursive least squares (RLS) and DFE significantly improves the error vector magnitude (EVM) performance compared with the DFE. In addition, the digital signal processing (DSP) complexity is discussed.

Berberine inhibits lipopolysaccharide-induced expression of inflammatory cytokines by suppressing TLR4-mediated NF-ĸB and MAPK signaling pathways in rumen epithelial cells of Holstein calves.

Subacute ruminal acidosis (SARA) can increase the level of inflammation and induce rumenitis in dairy cows. Berberine (BBR) is the major active component of Rhizoma Coptidis, which is a type of Chinese anti-inflammatory drug for gastrointestinal diseases. The purpose of this study was to investigate the anti-inflammatory effects of BBR on lipopolysaccharide (LPS)-stimulated rumen epithelial cells (REC) and the underlying molecular mechanisms. REC were cultured and stimulated with LPS in the presence or absence of different concentrations of BBR. The results showed that cell viability was not affected by BBR. Moreover, BBR markedly decreased the concentrations and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in the LPS-treated REC in a dose-dependent manner. Importantly, Western blotting analysis showed that BBR significantly suppressed the protein expression of toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein (MyD88) and the phosphorylation of nuclear factor-κB (NF-κB), inhibitory kappa B (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in LPS-treated REC. Furthermore, the results of immunocytofluorescence showed that BBR significantly inhibited the nuclear translocation of NF-κB p65 induced by LPS treatment. In conclusion, the protective effects of BBR on LPS-induced inflammatory responses in REC may be due to its ability to suppress the TLR4-mediated NF-κB and MAPK signaling pathways. These findings suggest that BBR can be used as an anti-inflammatory drug to treat inflammation induced by SARA.