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1.
Opt Express ; 27(20): 27562-27572, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684521

RESUMO

A noteworthy challenge in actual wireless sensors is the intrinsic sensing resolution and the sensitivity associated with the response to external perturbation to be measured. To address the issue, we report the realization of enhanced sensitivity in a passive wireless sensing system, consisting of three coupled passive resonators. The input wave is exploited as an effective gain in our open system, thus the ideal parity-time (PT) symmetry can be established, rather than balancing real gain and loss. Then the third-order exceptional points are obtained in ternary PT symmetric systems. With the extrinsic perturbation imposed on any one of resonators, we demonstrate analytically and experimentally that the resonance response of the system follows the cube-root dependence on perturbation. Making use of the effective gain, our results pave a new way, to the best of our knowledge, to realize the ultra-sensitivity of a passive wireless sensing system.

3.
Am J Nephrol ; : 1-10, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694015

RESUMO

BACKGROUND: Inflammation plays an important role in polycystic kidney disease (PKD). Cordyceps sinensis, a prized -Chinese medicinal herb, exerts anti-tumor, anti-inflammatory and anti-metastatic effects and benefits patients with kidney diseases. The aim of this study was to test the efficacy of FTY720, an immunosuppressant derived from C. sinensis, in a rat cystic kidney disease model, and explore its underlining mechanism. METHODS: Male wild type and Cy/+ Han:SPRD rats were treated with FTY720 at 3 and 10 mg/kg/day for 5 weeks and 12 weeks by gavage. Blood and kidney were collected for functional, morphological, RNA, and protein analysis. RESULTS: Inflammation is activated in Cy/+ Han:SPRD rats. Inflammatory cytokines including interleukin 6 and tumor necrosis factor alpha were upregulated and inflammation-related pathways were activated, such as nuclear factor κB and signal transducer and activator of transcription 3 (STAT3) pathways. Furthermore, the bioactive sphingolipid mediator sphingosine-1-phosphate (S1P), a regulator of inflammation, was accumulated in the Cy/+ Han:SPRD rats. FTY720 significantly reduced cyst growth and delayed disease progression by reducing the accumulation of S1P, thereby inhibiting inflammatory responses. CONCLUSION: FTY720 treatment reduced the expression of inflammatory cytokines and attenuated the activation of NK-κB and STAT3 pathways in Cy/+ Han:SPRD rats. It suggests that FTY720 may serve as a therapeutic agent for clinical autosomal dominant PKD treatment.

4.
Dev Comp Immunol ; 103: 103529, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669309

RESUMO

The myeloid differentiation protein 2 (MD2)-related lipid-recognition (ML) proteins display diverse biological functions in host immunity and lipid metabolism by interacting with different lipids. Human MD2, an indispensable accessory protein in TLR4 signaling pathway, specifically recognizes lipopolysaccharides (LPS), thereby leading to the activation of TLR4 signaling pathway to produce many effectors that participate in inflammatory and immuneresponses against Gram-negative bacteria. Toll and immune deficiency (IMD) pathways are first characterized in Drosophila and are reportedly present in crustaceans, but the recognition and activation mechanism of these signaling pathways in crustaceans remains unclear. In the present study, a novel ML protein was characterized in mud crab (Scylla paramamosain) and designated as SpMD2. The complete SpMD2 cDNA sequence is 1114 bp long with a 465 bp open reading frame; it encodes a protein that contains 154 amino acids (aa). In the deduced protein, a signal peptide (1-21 aa residues) and a ML domain (43-151 aa residues) were predicted. SpMD2 shared a similar three-dimensional structure and a close evolutionary relationship with human MD2. SpMD2 was highly expressed in gills, hemocytes, intestine, and hepatopancreas and was upregulated in gills and hemocytes after challenges with bacteria, thereby suggesting its involvement in antibacterial defense. Western blot assay showed that SpMD2 possesses strong binding activities to different bacteria and two fungi. ELISA demonstrated that SpMD2 exhibits binding abilities to LPS, lipid A, peptidoglycan (PGN), and lipoteichoic acid (LTA). Its binding ability to LPS and lipid A were stronger than to PGN or LTA, implying that SpMD2 was an important LPS-binding protein in mud crab. Bacterial clearance assay revealed that the pre-incubation of Vibrio parahemolyticus with SpMD2 facilitates bacterial clearance in vivo and that knockdown of SpMD2 dramatically suppresses the bacterial clearance and decreases the expression of several antimicrobial peptides (AMPs). Furthermore, SpMD2 overexpression could enhance the promoter activity of SpALF2. These results revealed that SpMD2 affects bacterial clearance by regulating AMPs. Thus, by binding to LPS and by regulating AMPs, SpMD2 may function as a potential receptor, which is involved in the recognition and activation of a certain immune signaling pathway against Gram-negative bacteria. This study provides new insights into the diverse functions of ML proteins and into the antibacterial mechanisms of crustaceans.

5.
BMC Surg ; 19(1): 161, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31690303

RESUMO

BACKGROUND: Wound-related complications are an inevitable issue faced by spinal surgeons. Negative pressure drainage remains the most commonly used method to prevent postoperative hematoma and related complications. This prospective, randomized, controlled study was conducted to evaluate the efficacy of compression therapy following posterior lumbar interbody fusion, with emphasis on pain, anemia, and inflammation. METHODS: Sixty consecutive patients who have undergone posterior lumbar interbody fusion in the age range 43-78 years, with an average age of 59 years, were selected and randomly assigned into two groups. Factors, such as drainage volume, visual analog scale (VAS) pain score for back pain, white blood cell (WBC) count, red blood cell (RBC) count, hemoglobin (Hb) levels, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels assessed on the 1st, 3rd, and 10th days postoperatively, were compared between the two groups. RESULTS: The average follow-up was 6 months, ranging from 3 to 11 months. Drainage volume, VAS score, and CRP levels on the 10th day after the surgery were found to be significantly lower in the treatment group than in the control group. RBC count and Hb levels on the 3rd and 10th postoperative days were observed to be significantly higher in the treatment group than in the control group (P < 0.05). During discharge, the wounds of the patients of the both groups had healed and neither showed any symptoms of infection, hematoma, or necrosis. CONCLUSION: Compression therapy relieves pain, alleviates anemia, and the inflammatory response following posterior lumbar interbody fusion. TRIAL REGISTRATION: ChiCTR1800015825 on chictr.org.cn, April 23, 2018, the trial registry is Chinese Clinical Trial Registry.

6.
Molecules ; 24(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671644

RESUMO

Sesquiterpenoids constitute a marvelously varied group of natural products that feature a vast array of molecular architectures. Among them, the unusual bicyclo [6.3.0] undecane sesquiterpenoids are one of the most representative. To date, only approximately 42 naturally occurring compounds with this unique scaffold, which can be classified into seven different groups, have been reported. As the first-found member of each type, dactylol, asteriscanolide, dumortenol, toxicodenane C, and capillosanane S are characteristic of the four methyl groups on the five-eight-membered ring system. Only 11-hydroxyjasionone and sinuketal decorate the core with an isopropyl group. These natural products exhibit a wide range of bioactivities, including antifouling, anti-inflammatory, immune suppression, cytotoxic, antimutagenic, antiplasmodial, and antiviral activities. It was noted that some total syntheses of precapnellane-sesquiterpenoids (dactylol, poitediol, precapnelladiene), asteriscanolide, and 11-hydroxyjasionone have been achieved, because their cyclooctanoid core represents an important target for the development of synthetic strategies to prepare eight-membered ring-containing compounds. This review focuses on these natural sesquiterpenoids and their biological activities and synthesis, and aims to provide a foundation for further research of these interesting compounds.

7.
Chemistry ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573724

RESUMO

Since the first perovskite CaTiO3 was discovered in 1839s, the development of perovskite has a history of 180 years. The emergence of solar cells-(CH3NH3)PbI3 has set off the trend of hybrid organic-inorganic perovskite (HOIP) materials. Since then, various HOIPs have sprung up and been widely used in various material devices. Among them, HOIP ferroelectrics have gained widespread attention. However, antiperovskite, as a twin brother of perovskite, has been neglected although it has similar structure with perovskite. Here, we successfully found that [C3H7FN]3[SnCl6]Cl (1) has a three-dimensional (3D) antiperovskite structure with the formula M3AB. Importantly, 1 exhibits obvious ferroelectric properties with an Aizu notation of 622F6 at 391 K. To the best of our knowledge, this is the first 3D hybrid organic-inorganic antiperovskite ferroelectric, which will greatly promote the development of antiperovskite families with more superior physical properties.

8.
Biomark Med ; 13(15): 1255-1261, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31580146

RESUMO

Aim: The prognostic role of neutrophil-to-lymphocyte ratio (NLR) in bloodstream infection (BSI) deserves further investigation. Patients & methods: The NLR values were measured and compared in BSI patients and healthy controls. The receiver operating characteristic of NLR and cut-off values were measured in BSI patients and subgroups. Results: We have measured the NLR of study group with 2160 BSI patients and normal group with 2523 healthy controls, which was significantly high in study group (11.36 ± 21.38 vs 2.53 ± 0.86; p < 0.001) and the area under the curve was 0.834 (95% CI: 0.825-0.842; p < 0.001). The critical value of NLR for diagnosis of BSI was 3.09, with a sensitivity of 75.3%, and a specificity of 93.6%. Conclusion: NLR is an effective diagnostic indicator of including BSIs of Gram-negative bacteria, Gram-positive bacteria and fungus.

9.
J Orthop Surg (Hong Kong) ; 27(3): 2309499019879540, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31645192

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. METHODS: Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. RESULTS: OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). CONCLUSION: OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.

10.
J Immunol ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645417

RESUMO

The pharyngeal organ is located at the crossroad of the respiratory and digestive tracts in vertebrate, and it is continuously challenged by varying Ags during breathing and feeding. In mammals, the pharyngeal mucosa (PM) is a critical first line of defense. However, the evolutionary origins and ancient roles of immune defense and microbiota homeostasis of PM are still unknown. In this study, to our knowledge, we are the first to find that diffuse MALT is present in PM of rainbow trout, an early vertebrate. Importantly, following parasitic infection, we detect that strong parasite-specific mucosal IgT and dominant proliferation of IgT+ B cell immune responses occurs in trout PM, providing, to our knowledge, the first demonstration of local mucosal Ig responses against pathogens in pharyngeal organ of a nonmammal species. Moreover, we show that the trout PM microbiota is prevalently coated with secretory IgT and, to a much lesser degree, by IgM and IgD, suggesting the key role of mucosal Igs in the immune exclusion of teleost pharyngeal bacteria. Overall, to our knowledge, our findings provide the first evidence that pharyngeal mucosal immunity appear earlier than tetrapods.

11.
Crit Rev Anal Chem ; : 1-32, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31646873

RESUMO

Cephalosporins, one of the classic ß-lactam antibiotics, has been widely concerned by global population as the most commonly used broad-spectrum antibiotic. Serious health hazards are possible to be posed by quality control problems caused by its unstable structure, as well as food and environmental pollution introduced by improper use. Given the reasons above, the sensitive and valid methods for monitor and determination of cephalosporins in different matrices are urgently required. This review aims to provide a comprehensive overview on the current status of the pretreatment and analysis methods of cephalosporins in bulk drug, pharmaceutics, animal-derived foodstuffs including eggs, milk, meat, environment samples, and biological samples. Pretreatment methods including simple steps (protein precipitation, centrifugation, filtration), liquid-liquid extraction, solid phase extraction, QuECHERS, and detection methods covering LC, LC-MS/MS, voltammetric sensor, capillary electrophoresis spectroscopy, biological methods from January 2005 to October 2018 are updated, elaborated and compared here. Moreover, advanced materials and prospects for development are discussed. Highlights Determination of cephalosporins in different newly found matrix are represented. Comparisons between different mass analyzers and progress in HRMS methods are in detailed. Optimization of experimental conditions are discussed. Newly emerged eco-friendly methods are introduced.

12.
Eur J Pharmacol ; 864: 172719, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586634

RESUMO

Gambogic acid (GA) is a potential anti-cancer compound that is extracted from the resin of Garciania hanburyi. The present study was designed to evaluate the anti-metastatic effect of GA on melanoma cell lines in vitro and to explore the underlying mechanism. The anti-proliferative activity of GA on melanoma cells was assessed by CCK-8 assay. The Wound-healing, transwell, adhesion, and tube formation assays were performed to examine the inhibition of GA on the cell's migration, invasion, adhesion, and angiogenesis capacities, respectively. Enzymatic activity of MMP-2 and MMP-9 were detected by gelatin zymography assay. Protein expressions regulated by GA treatment were tested by Western blot assay. The present results showed that GA significantly inhibited the proliferation of highly metastatic melanoma A375, B16-F10 cells and human umbilical vein endothelial cells (HUVECs) in time- and doses-dependent manners. Furthermore, GA significantly inhibited the migratory, invasive and adhesive properties of A375 and B16-F10 cells, and tube-forming potential of HUVECs at sub-IC50 concentrations, where no significant cytotoxicity was observed. Mechanistically, GA treatment suppressed the EMT and angiogenesis processes and reduced the enzymatic activity of MMP-2 and MMP-9. Moreover, abnormal PI3K/Akt and ERK signaling pathways in A375 and B16-F10 cells and HUVECs were notably suppressed by GA treatment. Collectively, our results suggest that GA exerts anti-metastasis activity in melanoma cells by suppressing the EMT and angiogenesis through the PI3K/Akt and ERK signaling pathways, and might be used as a phytomedicine against metastatic melanoma.

13.
Analyst ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31663528

RESUMO

A novel YVO4:Eu3+@CDs core-shell nanomaterial with two main emission peaks at 405 and 617 nm was synthesized through a simple mixing method, in which the carbon quantum dots (CDs) self-assembled with the YVO4:Eu3+ nanoparticle, due to the high affinity of oxygen-containing groups such as -COOH or -OH of CDs to the metal ions on the surface of YVO4:Eu3+. The red fluorescence of YVO4:Eu3+@CDs located at 617 nm can be quenched by Cu2+ ions efficiently, while the blue emission remains invariable; based on this, we construct a ratio fluorescent probe YVO4:Eu3+@CDs for Cu2+ ion detection, in which the blue emission of CDs is selected as the reference signal, and the red emission of YVO4:Eu3+ acts as an output signal. Furthermore, the addition of biothiol recovers the quenched red fluorescence quickly, which can be completed in 18 minutes. Thus, YVO4:Eu3+@CDs can also be used as a 'turn on' ratio fluorescent probe for biothiol rapid detection. Taking l-cysteine (l-Cys) as the model, the fluorescence intensity of the 617 nm peak increases with increasing Cys, and the ratio of F617/F405 is linear to the concentration of Cys in the range of 0.1 µM to 10 µM with a detection limit of 41 nM. Compared with these single wavelength emission biothiol fluorescent probes, an obvious change in the fluorescence color from blue to pink can be conveniently observed by the naked eye under a UV lamp. Meanwhile, this ratiometric probe has also been demonstrated to be used for the visual identification of biothiols in real blood serum samples.

14.
Zhongguo Gu Shang ; 32(9): 802-806, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31615174

RESUMO

OBJECTIVE: To explore the influence of individual characteristics of patients on the kinematics parameters of sitting lumbar spine manipulation. METHODS: From January 2016 to December 2016, 30 patients with degenerative lumbar spondylolisthesis were treatede, including 18 males and 12 females, aged from 45 to 61(52.33±2.34) years old, with a course of 2 to 72(29.13±3.23) months. Motion capture technique was used to measure the kinematics parameters of the same manipulator in sitting lumbar spine manipulation for 30 patients, including rotation time, maximum speed and maximum acceleration. The parameters of the left and right hands of the operator were different. The effects of individual characteristics on the kinematics parameters of sitting lumbar spine manipulation were analyzed. RESULTS: The kinematic and mechanical parameters of manipulation were as follows:spin time, maximum speed, maximum acceleration, the manipulation done by right or left hand showed the similar parameters(P>0.05). According to multivariate linear regression, there was a significant correlation between the age of the patient and the rotation time of the operator(P<0.01); the height of patient had a significant correlation with the maximum speed and maximum acceleration of the operator(P<0.01). CONCLUSIONS: There is no difference between the manipulation of left and right hand in clinical application. Age and height are important influencing factors of sitting lumbar rotation manipulation.

15.
Zhongguo Zhong Yao Za Zhi ; 44(14): 3022-3034, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31602849

RESUMO

To characterize the chemical constituents of Huanbei Zhike Prescription by ultra-high performance liquid chromatography-time of flight mass spectrometry( UPLC-Q-TOF-MS/MS). A Thermo Syncronls C18 column( 2. 1 mm×100 mm,1. 7 µm) was used with methanol( A)-0. 1% formic acid solution( B) as the mobile phase for gradient elution. The injection volume was 2 µL; the column temperature was 40 ℃; the flow rate was 0. 3 m L·min-1; and electrospray ionization( ESI) source was used to collect data in positive and negative ion modes. The ion scanning range was m/z 50-1 200,with capillary voltage of 3 000 V,ion source temperature of100 ℃,atomization gas flow rate of 50 L·h-1,desolvent gas flow rate of 800 L·h-1,desolvent temperature of 400 ℃,cone hole voltage of 40 V,with argon as the collision gas and the collision energy was 20-35 V. The excimer ion peak information was analyzed by Waters UNIFI data processing software. The molecular formula with error within 1×10-5 was compared with the data in database to identify the compounds. The secondary fragment ion information of the target compound was selected,and then compared with the retention time and fragmentation patterns provided by the database and the existing literature to further confirm the compositions and structures of the compounds. A total of 68 main compounds in Huanbei Zhike Prescription were identified,including 38 flavonoids,10 organic acids,6 terpenoids and 10 nitrogen-containing compounds,of which 12 compounds were verified by the control substances. This method is rapid and accurate,which provides a new strategy for the qualitative analysis of the chemical constituents of Huanbei Zhike Prescription,and lays a foundation for the further study and quality control of the compound pharmacodynamic substance.


Assuntos
Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Espectrometria de Massas em Tandem , Terpenos/análise
16.
Molecules ; 24(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627373

RESUMO

Sweet potato anthocyanins are water-soluble pigments with many physiological functions. Previous research on anthocyanin accumulation in sweet potato has focused on the roots, but the accumulation progress in the leaves is still unclear. Two purple sweet potato cultivars (Fushu No. 23 and Fushu No. 317) with large quantities of anthocyanin in the leaves were investigated. Anthocyanin composition and content were assessed with ultra-performance liquid chromatography diode-array detection (UPLC-DAD) and ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS), and the expressions of genes were detected by qRT-PCR. The two cultivars contained nine cyanidin anthocyanins and nine peonidin anthocyanins with an acylation modification. The acylation modification of anthocyanins in sweet potato leaves primarily included caffeoyl, p-coumaryl, feruloyl, and p-hydroxy benzoyl. We identified three anthocyanin compounds in sweet potato leaves for the first time: cyanidin 3-p-coumarylsophoroside-5-glucoside, peonidin 3-p-coumarylsophoroside-5-glucoside, and cyanidin 3-caffeoyl-p-coumarylsophoroside-5-glucoside. The anthocyanidin biosynthesis downstream structural genes DFR4, F3H1, anthocyanin synthase (ANS), and UDP-glucose flavonoid 3-O-glucosyltransferase (UFGT3), as well as the transcription factor MYB1, were found to be vital regulatory genes during the accumulation of anthocyanins in sweet potato leaves. The composition of anthocyanins (nine cyanidin-based anthocyanins and nine peonidin-based anthocyanins) in all sweet potato leaves were the same, but the quantity of anthocyanins in leaves of sweet potato varied by cultivar and differed from anthocyanin levels in the roots of sweet potatoes. The anthocyanidin biosynthesis structural genes and transcription factor together regulated and controlled the anthocyandin biosynthesis in sweet potato leaves.

17.
Plant Physiol ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628150

RESUMO

Circular RNAs (circRNAs) play roles in various biological processes, but their functions in the rice (Oryza sativa) response to Magnaporthe oryzae remain elusive. Here, we demonstrate that circRNAs are involved in the rice-M. oryzae interaction using comparative circRNA-seq and transgenic approaches. We identified 2932 high-confidence circRNAs from young leaves of the blast-resistant accession International Rice Blast Line Pyricularia-Kanto51-m-Tsuyuake (IRBLkm-Ts, IR25) and the blast-susceptible accession Lijiangxin Tuan Heigu (LTH) under M. oryzae-infected or uninfected conditions; 636 were detected specifically upon M. oryzae infection. The circRNAs in IR25 were significantly more diverse than those in LTH, especially under M. oryzae infection. Particularly, the number of circRNAs generated per parent gene was much higher in IR25 than in LTH and increased in IR25 but decreased in LTH upon M. oryzae infection. The higher diversity of circRNAs in IR25 was further associated with more frequent 3' and 5' alternative back-splicing and usage of complex splice sites. Moreover, a subset of circRNAs was differentially responsive to M. oryzae in IR25 and LTH. We further confirmed that circR5g05160 promotes rice immunity against M. oryzae. Therefore, our data indicate that circRNA diversity is associated with different responses to M. oryzae infection in rice and provide a starting point to investigate a new layer of regulation in the rice-M. oryzae interaction.

18.
Nat Prod Res ; : 1-8, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31631686

RESUMO

A rare sinulariane-type norcembranoid sinulariadiolide B (1) with a unique cyano group, and a eunicellin-based diterpenoid multifloralin (2), along with two known related analogues, sinulariadiolide (3) and sclerophytin E (4), were isolated from the extract of the South China Sea soft coral Sinularia multiflora. Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with previously reported data. Compounds 2 and 4 showed potent antifouling activity against barnacle Balanus albicostatus.

19.
Drug Des Devel Ther ; 13: 3171-3180, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564833

RESUMO

Background: Emodin, a major component of Polygonum multiflorum (PM), has been reported to exert both protective and toxic effects in several cell types. However, the effects and underlying mechanisms of action of emodin in hepatic cells are still obscure. Methods: The present study used the normal human liver cell line L02 to investigate the effects and mechanisms of emodin in hepatic cells. After treatment with emodin, L02 cells were examined for viability, apoptosis and autophagy with the Cell Counting Kit-8 (CCK-8), annexin V/PerCP staining and GFP-LC3 plasmid transfection. The expression of proteins including cleaved caspase-3, LC3B-I/II, p-PI3K, PI3K, p-AKT, AKT, p-mTOR, mTOR and actin was examined by using Western blot. Results: Emodin significantly inhibited the viability of and induced apoptosis in L02 cells in a dose- and time-dependent manner. In addition, emodin increased the number of GFP-LC3 puncta in L02 cells and upregulated the expression of LC3B-II compared to those in control cells. Furthermore, emodin significantly decreased the expression of p-PI3K, p-AKT and p-mTOR in a dose-dependent manner compared to that in control cells without altering the expression of PI3K, AKT and mTOR. Notably, cotreatment with emodin and 3-methyladenine (3-MA) or rapamycin significantly increased and decreased the apoptosis rate of L02 cells, respectively, compared to that of cells treated with emodin alone. Conclusion:  In conclusion, emodin exhibited cytotoxicity in the L02 human hepatic cell line by promoting apoptosis, and it also induced autophagy through the suppression of the PI3K/AKT/mTOR signalling pathway. The autophagy could play a protective role following emodin treatment.

20.
Org Biomol Chem ; 17(41): 9217-9225, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31595928

RESUMO

An asymmetric catalytic multicomponent reaction of malononitrile, benzaldehyde, and α-arylidene pyrazolinones to produce spiropyrazolones has been reported. The [1 + 2 + 3] multicomponent reaction was catalyzed by chiral cinchona alkaloids to provide spiropyrazolones in high yields, with excellent enantioselectivities and good diastereoselectivities. We also performed control experiments and proposed a plausible catalytic cycle based on the observed experimental results to explain the reaction process and stereoselectivity of the asymmetric multicomponent reaction.

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