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•TFE can increase the secretion of TNF-α, IL-1β and IL-6, and up-regulate IL-10.•The mRNA and proteins expressions of iNOS and COX-2 were down-regulated by TFE.•TFE exhibited ...anti-inflammatory activity via inhibition NF-κB and MAPKs pathways.
Accompanied by the damages of epithelial and capillary endothelial cell, acute lung injury is diagnosed with the typical pathological symptoms in clinic, including diffusing of pulmonary interstitial, alveolar oedema and hypoxic respiratory insufficiency. Current study focused on the investigation the anti-inflammatory action and mechanisms of total flavonoids extract (TFE) from Abutilon theophrasti Medic. leaves on ALI mice induced by LPSs. Mice were administrated intragastrically with TFE at the concentrations of 0.25, 0.5, or 1.0 g/kg for 5 days, and on last day, nasal administration of LPSs for 6 h after 30 min for intragastric administration of TFE. Pretreatment with TFE not only reduced oxidative damage but also alleviated lung edema in ALI mice. Increased secretion of pro-inflammatory cytokines TNF-α, IL-1β and IL-6, caused by LPSs was reversed by TFE; on the contrary, the anti-inflammatory cytokine IL-10 was upregulated. The proteins expressions of pro-inflammatory mediators iNOS and COX-2 induced by LPSs, were down-regulated by TFE. Moreover, the activation of NF-κB and MAPK signalling pathways was inhibited by TFE in LPSs induced ALI mice. The results revealed that the anti-inflammatory mechanisms of TFE were via inhibition of NF-κB and MAPK activation. Combined, the results suggested that TFE might exert in vivo antioxidant and anti-inflammatory functions in LPSs stimulated mice, and will be potential in adjuvant treatment in oxidative stress and inflammation diseases.
Object detection in unmanned aerial vehicle (UAV) images is an important and challenging task for many applications, which often needs highly efficient detection algorithms to meet the accuracy and ...real-time requirements of the applications. In this article, we investigate efficient mechanisms for detecting dense and small objects in UAV images. Specifically, 1) kernel K-means is used to obtain optimal anchors for dense and small object detection; 2) a spatial information enhancement module is proposed to improve the detection accuracy of dense objects by extracting object spatial location information; 3) a Coord_C3 module is proposed to improve the receptive field of the network and to reduce the number of network parameters; and 4) a small detection head is added in the Head of the network and skip connections are employed in the Neck of the network to improve the detection accuracy of small objects. Experimental results on the VisDrone-2019, LEVIR-ship, and Stanford Drone datasets show that our method not only has higher detection accuracy but also runs faster compared to state-of-the-art detection methods.
TatD960 and TatD825 are DNases that contribute to biofilm formation and virulence in Trueperella pyogenes (T. pyogenes). Luteolin is a natural flavonoid commonly found in plants that exhibits ...antimicrobial capacity. Our study aims to investigate the effects of luteolin on TatD DNases as a natural inhibitor. In this research, the expression of tatD genes and TatD proteins in T. pyogenes treated with luteolin was detected, and then the effect of luteolin on the hydrolysis of DNA by TatD DNases was analyzed using agarose gel electrophoresis. Moreover, the interactions between luteolin and TatD DNases were tested using surface plasmon resonance (SPR) assays and molecular docking analysis. After 1/2 MIC luteolin treatment, the transcription of tatD genes and expression of TatD proteins appeared to be reduced in 80–90% of T. pyogenes (n = 20). The gel assay revealed that luteolin can inhibit the activity of TatD DNases. The SPR assay showed that the KD values of luteolin to TatD960 and TatD825 were 6.268 × 10−6 M and 5.654 × 10−6 M, respectively. We found through molecular docking that hydrogen bonding is predominant in the interaction of luteolin and TatD DNases. Our data indicate that luteolin inhibited the ability of TatD DNases by decreasing their binding to DNA. The current study provides an insight into the development of luteolin as a DNase inhibitor in preventing biofilm formation and virulence in T. pyogenes.
Trueperella pyogenes (T. pyogenes) is an opportunistic pathogen associated with a variety of diseases in many domestic animals. Therapeutic treatment options for T. pyogenes infections are becoming ...limited due to antimicrobial resistance, in which efflux pumps play an important role. This study aims to evaluate the inhibitory activity of luteolin, a natural flavonoid, on the MsrA efflux pump and investigate its mechanism. The results of antimicrobial susceptibility testing indicated that the susceptibility of msrA-positive T. pyogenes isolates to six macrolides increased after luteolin treatment, while the susceptibility of msrA-negative isolates showed no change after luteolin treatment. It is suspected that luteolin may increase the susceptibility of T. pyogenes isolates by inhibiting MsrA activity. After 1/2 MIC luteolin treatment for 36 h, the transcription level of the msrA gene and the expression level of the MsrA protein decreased by 55.0-97.7% and 36.5-71.5%, respectively. The results of an affinity test showed that the equilibrium dissociation constant (KD) of luteolin and MsrA was 6.462 × 10
M, and hydrogen bonding was predominant in the interaction of luteolin and MsrA. Luteolin may inhibit the ATPase activity of the MsrA protein, resulting in its lack of an energy source. The current study illustrates the effect of luteolin on MsrA in T. pyogenes isolates and provides insight into the development of luteolin as an innovative agent in combating infections caused by antimicrobial-resistant bacteria.
As an atmospheric phenomenon, haze significantly reduces the visibility of outdoor and remote sensing images. Remote sensing and outdoor imaging have different mechanisms, existing dehazing methods ...are hard to be applied for both outdoor images and remote sensing images. In this paper, an efficient dehazing method is proposed which can be applied for both outdoor and remote sensing images. Dehazing methods based on image enhancement and image restoration methods are both advantages of the proposed method. To address the problem of inaccurate calculation of transmittance in existing methods, a Gaussian-weighted image fusion is introduced to obtain a refined transmittance. In addition, to solve the problem of image colour distortion after dehazing, an unsharp mask method is used to correct the dehazed image. Experiments on the synthetic dataset and real dataset show that the proposed method is able to dehaze both the outdoor and remote sensing images, and outperforms existing methods by visual inspection. On the RICE remote sensing image dataset, the proposed method has an image peak signal-to-noise ratio of 27.08 and structural similarity of 0.94, which are higher than other methods.
TatD DNases are conserved proteins in a variety of organisms and are considered potential virulence factors in
Plasmodium falciparum
and
Streptococcus pneumoniae
. However, the function of TatD ...DNases has not yet been determined in
Trueperella pyogenes
, which causes various infections in animals and leads to economic losses. In this study, we describe the roles of TatD DNases in
T. pyogenes
(TpTatDs). A bioinformatics analysis was performed to investigate the sequence characteristics of TpTatDs, and then the ability of recombinant TatD proteins to hydrolyze DNA was determined in the presence of divalent cations. Moreover, we constructed
tatD
-deficient mutants. The biofilms formed by the wild-type and mutant strains were observed under a microscope. The mortality and bacterial load in the spleen of mice infected with the wild-type strain and
tatD
-deficient mutants were determined to obtain insights into the role of TatDs in the virulence of
T. pyogenes.
Two TatD DNases were identified in
T. pyogenes
. They were Mg
2+
-dependent DNases and exhibited DNA endonuclease activity. Compared with those formed by the parental strain, biofilms formed by mutants showed a significantly reduced thickness and biomass. Moreover, mutants produced a lower bacterial load in the spleen of mice and compromised virulence. Our data indicated that TatD DNases in
T. pyogenes
are involved in biofilm formation and required for virulence during infections.
The flavonoid fraction was extracted from the leaves of Abutilon theophrasti Medic., which are usually used as a traditional Chinese herbal medicine for the treatment of inflammation and joint pain. ...The current study focused on the extraction process, component analysis, and in vitro antioxidant, antibacterial, and anti-inflammatory activities of the flavonoid fraction as a part of ongoing research on bioactive substances from natural plant sources. This study evaluated the antioxidant activities via assays of DPPH radical scavenging capacity, ABTS radical scavenging capacity, and reducing power and investigated inhibitory activities against Escherichia coli, Salmonella, Staphylococcus aureus, and Streptococcus. Moreover, the inflammatory activity of the flavonoid fraction was estimated by measurement of the content of tumor necrosis factor alpha, interleukin-1-beta, interleukin-6, interleukin-10, nitric oxide, and cyclooxygenase-2 and the gene expression levels of several inflammation markers, such as inducible nitric oxide synthase and cyclooxygenase-2, in RAW 264.7 macrophages after LPS treatment. In addition, the underlying anti-inflammatory mechanisms, that is, the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways, were also revealed from the gene and protein expression levels. Taken together, these results suggested that the flavonoid fraction might exert in vitro antioxidant, antibacterial, and anti-inflammatory effects on LPS-stimulated RAW 264.7 macrophages and will be potentially useful as an adjuvant treatment for oxidative stress and bacterial and inflammatory diseases.
•The hybrid hollow-core polarization-maintaining fiber is based on hybrid light guiding effects, i.e. photonic bandgap mechanism and anti-resonant effect.•The birefringence of the fiber can reach ...above 10-3 with higher-order mode suppression ratio (HOMSR) greater than 100 within the wavelength range from 1.45 μm to 1.65 μm.•The high birefringence of the fiber can be achieved up 3.91 × 10-3 and the single mode bandwidth is up to 200 nm with the birefringence greater than 10-3.
A novel hybrid hollow-core polarization-maintaining fiber is proposed by combining the photonic bandgap mechanism and anti-resonant effect. High birefringence can be achieved by introducing a pair of negative curvature anti-resonant layers into the air core of a 7-cell HC-PBGF to obtain two-fold rational symmetry. Within the wavelength range from 1.45 μm to 1.65 μm, the birefringence reaches up to the magnitude order of 10-3 and high-order mode suppression ratio, which is defined as the ratio of the lowest loss of high-order modes to the highest loss of fundamental modes, is greater than 100. Hence, the proposed fiber can realize high birefringence and single mode simultaneously in the 200 nm wide wavelength range. Besides, an extended structure by changing the position of the anti-resonant layers also proves the advantages of hybrid structure in achieving high birefringence and single mode operation. The proposed hybrid structure owns great potential for polarization-sensitive applications and provides a new idea to design hollow-core polarization-maintaining fibers with high birefringence and single mode.
Petroleum ether extract from Abutilon theophrasti Medic. leaves was optimized by response surface methodology, and the optimal extraction conditions were as follows: ratio of solvent to material ...(20.12 mL/g), extraction time (5.45 h), and Soxhlet extraction temperature (61.32°C). And the yield of petroleum ether extract collected in August, September, and October was (2.05 ± 0.02)%, (2.39 ± 0.01)%, and (2.32 ± 0.02)%, respectively. The September and October extracts exhibited a better antioxidant activity, which was proved by DPPH·scavenging ability (IC
50
value of 327.5 and 331.5 μg/mL), ABTS
·+
scavenging ability (IC
50
value of 170.1 and 182.1 μg/mL), and reducing power (0.31 and 0.28 mmol Fe
2+
/100 μg/mL). Meanwhile, the gas chromatograph-mass spectrometry analysis revealed that the main antioxidant components contained 9, 12, 15-octadecatrienoic acid and 9, 12, 15-octadecatrienoic acid, ethyl ester (Z,Z,Z) in three petroleum ether extracts. Therefore, petroleum ether extract from Abutilon theophrasti Medic. leaves can be a potential resource of natural antioxidants in pharmaceutical, medicine, food, and chemical industries.
This article addresses the problem of the average stochastic finite-time synchronization (ASFTS) for a set of coupled neural networks (NNs) with energy-bounded noises. Due to the channel capacity ...constraint, the impulsive approach is introduced so as to cut down the communication times among the leader NNs and the follower NNs. Then, a nonfragile controller is designed to improve the robustness of the controller with randomly occurred uncertainty. The sufficient conditions that guarantee the ASFTS of the coupled NNs and the leader NNs are achieved. The boundary of the synchronization error is also obtained by constructing the monotonic increasing functions. Finally, the controller gains are given based on the derived conditions, and their effectiveness is illustrated by a numerical example.
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