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1.
Opt Lett ; 49(13): 3644-3647, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950230

RESUMO

Entangled dynamic and deterministic inter-symbol interferences (ISIs) induced by complicated channel impairments, limit the transmission capacity of intensity modulation and direct detection (IM/DD) systems. This Letter proposes a colored noise-suppressed channel shortening filter (CNS-CSF)-enabled maximum a posteriori (MAP) estimation (CNS-CSF-MAP) scheme to disentangle and mitigate deterministic and dynamic ISIs, where the CNS-CSF is deployed to perform the optimized dynamic ISI equalization with equalization-enhanced noise suppression, and the subsequent MAP algorithm is used to eliminate the residual deterministic ISI. The performance of the CNS-CSF-MAP scheme is evaluated and demonstrated in a C-band 61-Gb/s 100-km optical on-off keying (OOK) IM/DD system. The experimental results show that the proposed CNS-CSF-MAP scheme reaches the 20% and 7% forward error correction (FEC) thresholds at received optical powers (ROPs) of -6.6 dBm and -4 dBm, achieving 0.5- and 1.5-dB gains over a conventional post-filter-enabled MAP (PF-MAP) scheme.

2.
Sci Total Environ ; 930: 172861, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38685417

RESUMO

The mechanism of carboxymethylammonium chloride (CC) regulating cadmium (Cd) accumulation in rice was studied in field and hydroponic experiments. Field experiments showed that 0.2-1.2 mmol L-1 CC spraying effectively reduced Cd accumulation by 44 %-77 % in early rice grains and 39 %-78 % in late rice grains, significantly increased calcium (Ca) content and amino acids content in grains, as well as alleviated Cd-induced oxidative damage in leaves. Hydroponic experiments further verified the inhibition effect of CC on Cd accumulation. 1.2 mmol L-1 CC made the highest decrease of Cd content in shoots and roots of hydroponic seedlings by 45 % and 53 %, respectively. Exogenous CC significantly increased glutamate (Glu), glycine (Gly) and glutathione (GSH) content, and improved the activities of catalase (CAT) and superoxide dismutase (SOD) by 41-131 % and 11-121 % in shoots of hydroponic seedlings, respectively. Exogenous CC also increased the relative expression of OsGLR3.1-3.5 in the shoots and roots of hydroponic seedlings. The quantum computational chemistry was used to clarify that the Gly radical provided by CC could form various complexes with Cd through carboxyl oxygen atoms. These results showed that exogenous application of CC improved the tolerance to Cd by enhancing the antioxidant capacity; inhibited the absorption, transport and accumulation of Cd in rice by (1) promoting chelation, (2) increasing the GLRs activity through upregulating the content of Glu, Gly, as well as the expression of OsGLR3.1-3.5.


Assuntos
Cádmio , Oryza , Oryza/metabolismo , Oryza/genética , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas
3.
Sensors (Basel) ; 24(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474934

RESUMO

The demand for precise indoor localization services is steadily increasing. Among various methods, fingerprint-based indoor localization has become a popular choice due to its exceptional accuracy, cost-effectiveness, and ease of implementation. However, its performance degrades significantly as a result of multipath signal attenuation and environmental changes. In this paper, we propose an indoor localization method based on fingerprints using self-attention and long short-term memory (LSTM). By integrating a self-attention mechanism and LSTM network, the proposed method exhibits outstanding positioning accuracy and robustness in diverse experimental environments. The performance of the proposed method is evaluated under two different experimental scenarios, which involve 2D and 3D moving trajectories, respectively. The experimental results demonstrate that our approach achieves an average localization error of 1.76 m and 2.83 m in the respective scenarios, outperforming the existing state-of-the-art methods by 42.67% and 31.64%.

4.
Biochem Pharmacol ; 220: 115962, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043717

RESUMO

Puerarin (PUE), a flavonoid derivative with vasodilatory effects found in the traditional Chinese medicine kudzu, has anti-sensorineural hearing loss properties. However, the mechanism of its protective effect against ototoxicity is not well understood. In this study, we used in vitro and in vivo methods to investigate the protective mechanism of puerarin against cisplatin (CDDP)-induced ototoxicity. We established an ototoxicity model of CDDP in BALB/c mice and assessed the degree of hearing loss and cochlear cell damage. We used bioinformatics analysis, molecular docking, histological analysis, and biochemical and molecular biology to detect the expression of relevant factors. Our results show that puerarin improved CDDP-induced hearing loss and reduced hair cell loss. It also blocked CDDP-induced activation of TRPV1 and inhibited activation of IP3R1 to prevent intracellular calcium overload. Additionally, puerarin blocked CDDP-stimulated p65 activation, reduced excessive ROS production, and alleviated cochlear cell apoptosis. Our study provides new evidence and potential targets for the protective effect of puerarin against drug-induced hearing loss. Puerarin ameliorates cisplatin-induced ototoxicity and blocks cellular apoptosis by inhibiting CDDP activated TRPV1/IP3R1/p65 pathway, blocking induction of calcium overload and excessive ROS expression.


Assuntos
Antineoplásicos , Perda Auditiva , Isoflavonas , Ototoxicidade , Animais , Camundongos , Antineoplásicos/efeitos adversos , Apoptose , Cálcio/metabolismo , Linhagem Celular , Cisplatino/efeitos adversos , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , Perda Auditiva/metabolismo , Simulação de Acoplamento Molecular , Espécies Reativas de Oxigênio/metabolismo , Canais de Cátion TRPV/genética
5.
Opt Express ; 31(20): 32529-32542, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859054

RESUMO

A polynomial nonlinear filter (PNLF)-based electrical dispersion pre-compensation (pre-EDC) scheme assisted with Gerchberg-Saxton (GS) algorithm is proposed to compensate the chromatic dispersion (CD) for intensity-modulation and direct-detection (IM/DD) optical transmission systems, where PNLF is utilized to fit the nonlinear transfer function of the iterative GS algorithm-based pre-EDC scheme to realize a low-complexity non-iterative CD pre-compensation. The capability of PNLF to fit the nonlinear iterative process enables the PNLF-based pre-EDC scheme to compensate for CD-induced linear distortions and address CD-induced nonlinear distortions, which are typically captured through iterative approaches. Additionally, to further reduce the computational complexity, we also introduce the k-means clustering algorithm to eliminate the weight redundancy and propose a lower-complexity clustered PNLF-based pre-EDC scheme. Simulation results show that PNLF-based and clustered PNLF-based pre-EDC schemes save 76.0% and 97.5% complexity with only 0.3 dB receiver sensitivity penalty at 20% forward error correction (FEC) threshold, compared with GS-based pre-EDC scheme in C-band 56 GBaud 80-km on-off keying (OOK) system. Furthermore, the effectiveness of PNLF-based and clustered PNLF-based pre-EDC schemes is also evaluated through the experimental demonstration. Experimental results show that under C-band 32 GBaud 80-km OOK system, bit error ratio (BER) satisfying 20% FEC threshold is achieved by applying PNLF-based and clustered PNLF-based pre-EDC schemes, which save 78.3% and 94.2% complexity with only 0.4 dB receiver sensitivity penalty compared with GS-based pre-EDC scheme, respectively. The research results indicate that the (clustered) PNLF-based pre-EDC scheme has the great application potential for CD compensation in high-performance and low-cost IM/DD optical transmission systems.

6.
Environ Monit Assess ; 195(11): 1379, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37882903

RESUMO

Nitrogen dioxide (NO2) concentration is a crucial indicator of ground-level air quality, and elevated concentrations can adversely affect human health and the atmospheric environment. In this study, we utilized Tropospheric Monitoring Instrument (TROPOMI) tropospheric NO2 vertical column density data (VCD) and multi-source geographic data to establish a random forest regression (RF) model that accurately estimates NO2 concentrations near the ground in the Fenwei Plain. The model addresses the inherent limitations of traditional ground-based monitoring and provides data support for analyzing regional pollution spatial and temporal characteristics. (1) The RF model based on TROPOMI and geographic data demonstrates high estimation accuracy, with monthly average RF model fit and validation coefficient of determination (R2) reaching 0.949 and 0.875, respectively. (2) A complex nonlinear relationship exists between near-surface NO2 concentration and multi-source geographic data. The RF model's estimations reveal clear seasonal and regional variations in near-surface NO2 concentration. Concentrations are generally highest in winter, followed by spring and autumn, and lowest in summer. The high NO2 concentrations are primarily mainly distributed in the plains and river valleys with low elevation and dense population density. The model estimation results also indicate that the estimated effect is better when the NO2 concentration fluctuates less and anthropogenic emission reduction measures significantly impact the NO2 concentration near the ground. (3) The population exposure risk results indicate that most cities in the Fenwei Plain face varying exposure risks. These findings offer valuable insights for regional NO2 pollution management.


Assuntos
Dióxido de Nitrogênio , Algoritmo Florestas Aleatórias , Humanos , Monitoramento Ambiental , China , Rios
7.
Opt Express ; 31(12): 18888-18897, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381318

RESUMO

In this paper, a low-complexity optimized detection scheme consisting of a post filter with weight sharing (PF-WS) and cluster-assisted log-maximum a posteriori estimation (CA-Log-MAP) is proposed. Besides, a modified equal-width discrete (MEWD) clustering algorithm is proposed to eliminate the training process during clustering. After channel equalization, optimized detection schemes improve performance by suppressing the in-band noise raised by the equalizers. The proposed optimized detection scheme was experimentally performed in a C-band 64-Gb/s on-off keying (OOK) transmission system over 100-km standard single-mode fiber (SSMF) transmission. Compared with the optimized detection scheme with the lowest complexity, the proposed method saves 69.23% required number of real-valued multiplications per symbol (RNRM) at 7% hard-decision forward error correction (HD-FEC). In addition, when the detection performance reaches saturation, the proposed CA-Log-MAP with MEWD saves 82.93% RNRM. Compared with the classic k-means clustering algorithm, the proposed MEWD has the same performance without a training process. To the best of our knowledge, this is the first time clustering algorithms have been applied to optimize decision schemes.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37274058

RESUMO

Background: Recent therapeutic approaches have improved survival rate for women with breast cancer, but the survival rate for metastatic breast cancer is still low. Exosomes released by various cells are involved in all steps of breast cancer development. Methods: We established the multimodal imaging report expression in breast cancer cells with lentivirus vectors pGluc and pBirA to investigate the secreted exosomes. Comparative microRNA (miRNA) analysis was performed with miRNA qPCR array in mice with breast cancer lung metastasis. The co-immunoprecipitation and chromatin immunoprecipitation assays were used to identify the mechanism of miRNA sorting to exosomes. The potential therapeutic strategy using an anti-sorting antibody was used to investigate breast cancer lung metastasis. Results: We identified 26 high- and 32 low-expression level miRNAs in exosomes from metastasis compared to those from primary tumors and normal tissues. The tumor suppressors, including miR-200c and let-7a, were reduced in tumor tissues and metastasis but increased in the respective exosomes compared to normal tissues. Furthermore, the Ras-related protein (Rab1A) facilitated miR-200c sorting to exosomes circumventing the influence of tumor suppressor miR-200c on tumor cells, while the metastatic exosome cargo miR-200c inhibited F4/80+ macrophage immune response. Administration of anti-Rab1A antibody significantly repressed the trafficking of miR-200c to exosomes and breast cancer lung metastasis. Conclusion: Our study has identified a novel molecular mechanism for breast cancer lung metastasis mediated by exosome cargo miRNAs and provided a new therapeutic strategy for cancer immunotherapy.

9.
Nanomaterials (Basel) ; 13(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37110973

RESUMO

Perovskites with nano-flexible texture structures and excellent catalytic properties have attracted considerable attention for persulfate activation in addressing the organic pollutants in water. In this study, highly crystalline nano-sized LaFeO3 was synthesized by a non-aqueous benzyl alcohol (BA) route. Under optimal conditions, an 83.9% tetracycline (TC) degradation and 54.3% mineralization were achieved at 120 min by using a coupled persulfate/photocatalytic process. Especially compared to LaFeO3-CA (synthesized by a citric acid complexation route), the pseudo-first-order reaction rate constant increased by 1.8 times. We attribute this good degradation performance to the highly specific surface area and small crystallite size of the obtained materials. In this study, we also investigated the effects of some key reaction parameters. Then, the catalyst stability and toxicity tests were also discussed. The surface sulfate radicals were identified as the major reactive species during the oxidation process. This study provided a new insight into nano-constructing a novel perovskite catalyst for the removal of tetracycline in water.

10.
Toxics ; 11(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36668797

RESUMO

To explore the effect of exogenous application of chlorinated amino acetic acid on cadmium (Cd) transport characteristics in rice seedlings, X24 and Z35 rice were taken as the research objects to carry out hydroponics experiments, and the changes of Cd content in rice seedlings, rice mineral elements and amino acid content in rice were analyzed. The results showed that exogenous application of 1.2 mmol·L-1 chlorinated amino acetic acid inhibited cadmium in shoots and roots of rice seedlings; Cd content in shoots and roots were reduced by up to 62.19% and 45.61%, respectively. The majority of cadmium was in the cell wall of shoots and roots; this decreased with the increase of the concentration of chlorinated acetic acid. In addition, the Mn content in shoots and Ca content in roots of rice seedlings increased significantly after the application of chlorinated amino acetic acid. The results of amino acid analysis showed that the contents of aspartic acid, glutamic acid and cystine in rice seedlings were increased. These results indicate that exogenous application of chlorinated amino acetic acid is beneficial to the synthesis of aspartic acid, glutamic acid and cysteine in rice seedlings, increases the content of Mn in shoots and Ca in roots of rice seedlings, and significantly alleviates cadmium stress in seedlings. This provides a theoretical basis for the development of an environmentally friendly Cd-lowering foliar fertilizer for rice.

11.
Front Psychiatry ; 14: 1267415, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38356614

RESUMO

Background: Depression is a common mental illness that is widely recognized by its lack of pleasure, fatigue, low mood, and, in severe cases, even suicidal tendencies. Photobiomodulation (PBM) is a non-invasive neuromodulation technique that could treat patients with mood disorders such as depression. Methods: A systematic search of ten databases, including randomized controlled trials (RCTs) for depression, was conducted from the time of library construction to September 25, 2023. The primary outcome was depression. The secondary outcome was sleep. Meta-analysis was performed using RevMan (version 5.4) and Stata (version 14.0). Subgroup analyses were performed to identify sources of heterogeneity. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Results: Three thousand two hundred and sixty-five studies were retrieved from the database and screened for inclusion in eleven trials. The forest plot results demonstrated that PBM alleviated depression (SMD = -0.55, 95% CI [-0.75, -0.35], I2 = 46%). But it is not statistically significant for patients' sleep outcomes (SMD = -0.82, 95% CI [-2.41, 0.77], I2 = 0%, p > 0.05). Subgroup analysis showed that s-PBM was superior to t-PBM in relieving symptoms of depression. The best improvement for t-PBM was achieved using a wavelength of 823 nm, fluence of 10-100 J/cm2, irradiance of 50-100 mW/cm2, irradiance time of 30 min, treatment frequency < 3/week, and number of treatments >15 times. The best improvement for s-PBM was achieved using a wavelength of 808 nm, fluence ≤1 J/cm2, irradiance of 50-100 mW/cm2, irradiance time ≤ 5 min, treatment frequency ≥ 3/week, number of treatments >15 times. All results had evidence quality that was either moderate or very low, and there was no bias in publication. Conclusion: We conclude that PBM is effective in reducing depression symptoms in patients. However, the current number of studies is small, and further studies are needed to extend the current analysis results. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/, CRD42023444677.

12.
J Gen Appl Microbiol ; 68(3): 125-133, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35650022

RESUMO

Flavone C-glycosides are not easily degraded because of their strong C-C bond between sugar moieties and aglycones. However, some bacteria such as intestinal species can produce specific enzymes to degrade them. In this study, a bacterial strain P581a, which is capable of deglycosylating flavone C-glycosides, was isolated from human intestinal bacteria and was identified as Enterococcus gallinarum by morphological examination, physiological and biochemical analysis and 16S rRNA gene sequencing. This strain may produce a specific flavonoside glycosidase. The activity of the enzyme in the culture medium containing different quantity of carbon sources was also studied, and it was found that the content of carbon sources is negatively correlated with the deglycosylation efficiency of this strain.


Assuntos
Flavonas , Glicosídeos , Humanos , RNA Ribossômico 16S/genética , Glicosídeos/análise , Glicosídeos/química , Glicosídeos/metabolismo , Bactérias/genética , Carbono
13.
Front Cell Dev Biol ; 9: 757747, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869346

RESUMO

miR-92a-3p (microRNA-92a-3p) has been reported to be dysregulated in several cancers, and as such, it is considered to be a cancer-related microRNA. However, the influence of miR-92a-3p on biological behaviors in cervical cancer (CC) still remains unclear. Quantitative real-time PCR was used to detect miR-92a-3p levels in CC stem cells. Here, Cell Counting Kit-8 (CCK8) assay, Transwell cell invasion assay and flow cytometry assay were used to characterize the effects that miR-92a-3p and large tumor suppressor l (LATS1) had on proliferation, invasion and cell cycle transition. The luciferase reporter gene assay was used to verify the targeting relationship between miR-92a-3p and LATS1. Western Blotting was used to investigate the related signaling pathways and proteins. Data from The Cancer Genome Atlas (TCGA) showed that miR-92a-3p was upregulated in CC tissues and closely associated with overall survival. miR-92a-3p promoted proliferation, invasion and cell cycle transition in CC stem cells. The luciferase reporter assay showed that miR-92a-3p bound to the 3'-untranslated region (3'-UTR) of the LATS1 promoter. LATS1 inhibited proliferation, invasion and cell cycle transition. Results measured by Western Blotting showed that LATS1 downregulated expressions of transcriptional co-activator with PDZ-binding motif (TAZ), vimentin and cyclin E, but upregulated the expression of E-cadherin. Re-expression of LATS1 partly reversed the effects of miR-92a-3p on proliferation, invasion and cell cycle transition, as well as on TAZ, E-cadherin, vimentin, and cyclin E. miR-92a-3p promoted the malignant behavior of CC stem cells by targeting LATS1, which regulated TAZ and E-cadherin.

14.
Pak J Pharm Sci ; 34(5): 1743-1748, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34803011

RESUMO

The effects of crude extract from the flowers of Trollius chinensis on expressions of mRNA and proteins related to vital genes (TLR 3, TBK 1, IRF 3 and IFN ß) in TLR 3 signaling pathway were investigated in the presence/absence of Polyinosinic acid-polycytidylic acid (PolyI: C) to ascertain the antiviral mechanism of these flowers. Real-time PCR and western blot were applied to determine the expressions of mRNA and proteins, respectively, and immunofluorescence assay was employed to study the effect on IRF 3 distribution between nuclei and cytoplasma. In the absence of PolyI:C, the crude extract reduced the mRNA expression of TLR 3, IRF 3 and IFN ß and the protein expression of TLR 3, and increased the protein expression of IRF 3 and the distribution of IRF 3 in nuclei. In the presence of PolyI:C, the extract reduced the mRNA and protein expressions of TLR 3 and the mRNA expression of IFN ß, meanwhile inhibited the translocation of IRF 3 into nuclei. The antiviral mechanism of the crude extract from the flowers of T. chinensis is to protect the host from inflammatory damage through intervening the TLR 3 signaling pathway and reducing the secretion of inflammatory factors.


Assuntos
Antivirais/farmacologia , Flores/química , Extratos Vegetais/farmacologia , Ranunculaceae/química , Transdução de Sinais/efeitos dos fármacos , Receptor 3 Toll-Like/metabolismo , Animais , Antivirais/química , Sobrevivência Celular , Cães , Regulação da Expressão Gênica/efeitos dos fármacos , Células Madin Darby de Rim Canino , Extratos Vegetais/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor 3 Toll-Like/genética
15.
Clin Transl Med ; 10(5): e175, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32997414

RESUMO

Pulmonary vascular remodeling is the most important pathological characteristic of pulmonary arterial hypertension (PAH). No effective treatment for PAH is currently available because the mechanism underlying vascular remodeling is not completely clear. CD248, also known as endosialin, is a transmembrane protein that is highly expressed in pericytes and fibroblasts. Here, we evaluated the role of CD248 in pulmonary vascular remodeling and the processes of PAH pathogenesis. Activation of CD248 in pulmonary artery smooth muscle cells (PASMCs) was found to be proportional to the severity of PAH. CD248 contributed to platelet-derived growth factor-BB (PDGF-BB)-induced PASMC proliferation and migration along with the shift to more synthetic phenotypes. In contrast, treatment with Cd248 siRNA or the anti-CD248 therapeutic antibody (ontuxizumab) significantly inhibited the PDGF signaling pathway, obstructed NF-κB p65-mediated transcription of Nox4, and decreased reactive oxygen species production induced by PDGF-BB in PAMSCs. In addition, knockdown of CD248 alleviated pulmonary vascular remodeling in rat PAH models. This study provides novel insights into the dysfunction of PASMCs leading to pulmonary vascular remodeling, and provides evidence for anti-remodeling treatment for PAH via the immediate targeting of CD248.

16.
Int J Mol Med ; 46(2): 806-816, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32626955

RESUMO

Cisplatin (CDDP) is widely used in clinical settings for the treatment of various cancers. However, ototoxicity is a major side effect of CDDP, and there is an associated risk of irreversible hearing loss. We previously demonstrated that CDDP could induce ototoxicity via activation of the transient receptor potential vanilloid receptor 1 (TRPV1) pathway and subsequent induction of oxidative stress. The present study investigated whether ursolic acid (UA) treatment could protect against CDDP­induced ototoxicity. UA is a triterpenoid with strong antioxidant activity widely used in China for the treatment of liver diseases. This traditional Chinese medicine is mainly isolated from bearberry, a Chinese herb. The present results showed that CDDP increased auditory brainstem response threshold shifts in frequencies associated with observed damage to the outer hair cells. Moreover, CDDP increased the expression of TRPV1, calpain 2 and caspase­3 in the cochlea, and the levels of Ca2+ and 4­hydroxynonenal. UA co­treatment significantly attenuated CDDP­induced hearing loss and inhibited TRPV1 pathway activation. In addition, UA enhanced CDDP­induced growth inhibition in the human ovarian cancer cell line SKOV3, suggesting that UA synergizes with CDDP in vitro. Collectively, the present data suggested that UA could effectively attenuate CDDP­induced hearing loss by inhibiting the TRPV1/Ca²+/calpain­oxidative stress pathway without impairing the antitumor effects of CDDP.


Assuntos
Antineoplásicos/farmacologia , Cálcio/metabolismo , Cisplatino/toxicidade , Canais de Cátion TRPV/metabolismo , Triterpenos/farmacologia , Animais , Western Blotting , Calpaína/metabolismo , Caspase 3/metabolismo , Cóclea/efeitos dos fármacos , Cóclea/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Medicina Tradicional Chinesa , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPV/genética , Ácido Ursólico
17.
J Ethnopharmacol ; 253: 112634, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32004628

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Flos Trollii is the dried flowers of Trollius chinensis. It has been used as a traditional herbal medicine for the treatment of upper respiratory tract infection, tonsillitis and pharyngitis in China for a long history. Veratric acid, vitexin, and trolline are the representative compounds of phenolic acids, flavonoids and alkaloids in this herbal medicine. All of these three compounds show antiviral activity which is related to the efficacy of Flos Trollii. AIM OF THE STUDY: To investigate the anti-influenza A virus mechanism of the three representative compounds from the perspective of regulating TLRs signaling pathways, so as to understand the relevant efficacy of Flos Trollii. MATERIALS AND METHODS: Influenza A virus A/FM/1/47 (H1N1) and mouse peritoneal macrophages (RAW264.7) were used in the whole process of investigation. MTT assay was conducted to select the appropriate experimental concentrations of the three compounds on RAW264.7 cells. Western blot, RT-PCR, and ELISA assays were performed to determine the protein and mRNA expression of key factors and related inflammatory factors of TLRs signaling pathways. Griess method was employed to detect the production of NO. RESULTS: The three representative compounds reduced the inflammatory factors including NO, IL-6, and TNF-α and enhanced the production of IFN-ß through dynamically regulating the TLRs 3, 4 and 7 pathways. Veratric acid significantly down-regulated the protein expression of TLR3 and IRF3 as well as the mRNA expression of TBK1 and TRIF. Vitexin significantly down-regulated the protein expression of TBK1 and IRF3 as well as the mRNA expression of TLR3, TBK1, TRIF and IRF3 while up-regulated the protein expression of TLR4 and IKKα. Trolline significantly down-regulated the protein expression of TLR7 whereas significantly up-regulated the protein expression of TLR4, IKKα and TAK1. CONCLUSIONS: The three representative compounds from Flos Trollii play their parts in anti-H1N1 viral effect through partially down-regulating TLRs 3 and 7 pathways and up-regulating TLR4 pathway. They counteract the inflammatory injury caused by excessive production of NO, IL-1, IL-6, and TNF-α induced by virus infection and enhance the production of IFN-ß so as to eliminate the virus.


Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Ranunculaceae/química , Animais , Antivirais/isolamento & purificação , Regulação para Baixo/efeitos dos fármacos , Flores , Interferon beta/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/virologia , Camundongos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Receptores Toll-Like/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
Opt Express ; 27(18): 25708-25717, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31510438

RESUMO

In this paper, a memory polynomial equalizer combined with decision feedback equalizer (MPE-DFE) is proposed to eliminate channel distortions for intensity modulation and direct detection (IM/DD) systems. Compared with traditional feedforward equalizer and decision feedback equalizer (FFE-DFE), the proposed MPE-DFE introduces extra square terms and cubic terms to jointly equalize chromatic dispersion and nonlinear distortions. We demonstrated a C-band 56-Gb/s four-level pulse-amplitude modulation (PAM4) system over 80-km standard single mode fiber (SSMF) transmission. Experimental results show that the proposed MPE-DFE achieved up to 6.2 dB higher SNR than traditional FFE-DFE. Moreover, the achieved bit error ratio (BER) with MPE-DFE reaches 3.1 × 10-3, which is below 7% feedforward error correction (FEC) threshold of 3.8 × 10-3. To the best of our knowledge, we achieved a record transmission distance for C-band 56-Gb/s PAM4 signal with only electrical equalization at the receiver.

19.
Zhen Ci Yan Jiu ; 44(4): 242-7, 2019 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-31056875

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on neurological behavior and activity of Toll-like receptor 2 / nuclear factor kappa B (TLR2/NF-κB) signaling of the ischemic cerebral area in cerebral ischemia-reperfusion injury (CIRI) rats, so as to explore its mechanisms underlying improvement of CIRI. METHODS: A total of 120 male SD rats were randomly divided into blank control, sham operation, model, EA and EA+NF-κB inhibitor (Pyrrolidine Dithiocarbamate Hydrochloride, PDTC, EA+PDTC) groups which were further divided into 3, 7, 14 and 28 d subgroups (n=6 in each subgroup). The CIRI model was established by occlusion of the middle cerebral artery for 90 min, followed by reperfusion. EA (1-20 Hz, 6 V) was applied to "Shuigou" (GV26), "Neiguan" (PC6), "Sanyinjiao" (SP6) and "Weizhong" (BL40) for 30 min, once a day for 28 days. For rats of the EA+PDTC group, PDTC solution (120 mg/kg) was intraperitoneally injected on the 3rd day after successful modeling and before EA intervention. The neurological deficit severity (Zea Longa score) was assessed 3, 7, 14 and 28 days after modeling. The expression levels of TLR2, Interleukin-1 receptor-associated kinase (IRAK) and NF-κB mRNAs in the ischemic penumbra region of brain tissue were detected by real-time fluorescence quantitative PCR. RESULTS: Following modeling, the neurological deficit scores were significantly increased from the 3rd day on after CIRI (P<0.05), the expression levels of TLR2 mRNA on day 3, 7, 14 and 28, and IRAK mRNA on day 3 and 7, as well as NF-κB mRNA on day 3, 7 and 14 were significantly up-regulated in the model group relevant to the blank control group (P<0.05). After EA intervention, the neurological deficit scores were significantly decreased in the EA group on day 3, 7 and 28 and in the EA+PDTC group on day 3, 7, 14 and 28 in comparison with those of the model group (P<0.05). In addition, the expression levels of TLR2 mRNA and NF-κB mRNA on day 3, 7 and 14 in the EA group, and on day 3, 7, 14 and 28 in the EA+PDTC group, IRAK mRNA on day 3 in the EA and EA+PDTC group were significantly down-regulated (P<0.05), but those of IRAK mRNA on day 14 and 28 in the EA group were significantly up-regulated in comparison with those of the model group (P<0.05). The effect of the EA+PDTC was obviously superior to that of simple EA in down-regulating the expression of TLR2 (on day 28), and IRAK (on day 3, 14, 28), and NF-κB (on day 3, 7 and 14) (all P<0.05). CONCLUSION: EA stimulation can improve the symptoms of neurological deficits in CIRI rats, which may be related to its effect in suppressing the expression of TLR2, NF-κB and IRAK mRNAs of the ischemic cerebral tissue, i.e., down-regulating the activity of TLR2/NF-κB signaling.


Assuntos
Isquemia Encefálica , Eletroacupuntura , Traumatismo por Reperfusão , Animais , Humanos , Masculino , NF-kappa B , Ratos , Ratos Sprague-Dawley , Receptor 2 Toll-Like
20.
Microb Cell Fact ; 18(1): 94, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138294

RESUMO

BACKGROUND: Flavone C-glycosides are difficult to be deglycosylated using traditional chemical methods due to their solid carbon-carbon bond between sugar moieties and aglycones; however, some bacteria may easily cleave this bond because they generate various specific enzymes. RESULTS: A bacterial strain, named W12-1, capable of deglycosylating orientin, vitexin, and isovitexin to their aglycones, was isolated from human intestinal bacteria in this study and identified as Enterococcus faecalis based on morphological examination, physiological and biochemical identification, and 16S rDNA sequencing. The strain was shown to preferentially deglycosylate the flavone C-glycosides on condition that the culture medium was short of carbon nutrition sources such as glucose and starch, and its deglycosylation efficiency was negatively correlated with the content of the latter two substances. CONCLUSION: This study provided a new bacterial resource for the cleavage of C-glycosidic bond of flavone C-glycosides and reported the carbon nutrition sources reduction induced deglycosylation for the first time.


Assuntos
Enterococcus faecalis/metabolismo , Fezes/microbiologia , Flavonas/metabolismo , Microbioma Gastrointestinal , Glicosídeos/metabolismo , Intestinos/microbiologia , Adulto , Apigenina/metabolismo , Carbono/metabolismo , Enterococcus faecalis/classificação , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Flavonoides/metabolismo , Glucosídeos/metabolismo , Humanos , Masculino , RNA Ribossômico 16S , Análise de Sequência de RNA
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