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1.
Chem Rev ; 124(6): 2889-2954, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483065

RESUMO

In recent years, the issues of global warming and CO2 emission reduction have garnered increasing global attention. In the 21st Conference of the Parties (convened in Paris in 2015), 179 nations and the European Union signed a pivotal agreement to limit the global temperature increase of this century to well below 2 K above preindustrial levels. To fulfill this objective, extensive research has been conducted to use renewable energy sources as potential replacements for traditional fossil fuels. Among them, the production of hydrocarbon transportation fuels from CO2-neutral and renewable biomass has proven to be a particularly promising solution due to its compatibility with existing infrastructure. This review systematically summarizes research progress in the synthesis of liquid hydrocarbon biofuels from lignocellulose during the past two decades. Based on the chemical structure (including n-paraffins, iso-paraffins, aromatics, and cycloalkanes) of hydrocarbon transportation fuels, the synthesis pathways of these biofuels are discussed in four separate sections. Furthermore, this review proposes three guiding principles for the design of practical hydrocarbon biofuels, providing insights into future directions for the development of viable biomass-derived liquid fuels.

2.
Molecules ; 29(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38998927

RESUMO

2-methylfuran is a significant organic chemical raw material which can be produced by hydrolysis, dehydration, and selective hydrogenation of biomass hemicellulose. 2-methylfuran can be converted into value-added chemicals and liquid fuels. This article reviews the latest progress in the synthesis of liquid fuel precursors through hydroxyalkylation/alkylation reactions of 2-methylfuran and biomass-derived carbonyl compounds in recent years. 2-methylfuran reacts with olefins through Diels-Alder reactions to produce chemicals, and 2-methylfuran reacts with anhydrides (or carboxylic acids) to produce acylated products. In the future application of 2-methylfuran, developing high value-added chemicals and high-density liquid fuels are two good research directions.

3.
Opt Lett ; 48(4): 1028-1031, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791002

RESUMO

We present a photonics-based method of estimating Doppler frequency shift (DFS) and angle of arrival (AOA). The proposed identification method for the DFS and AOA is simultaneous and unambiguous. A reference radio frequency signal is introduced to realize the frequency downconversion. By monitoring the frequency of the downconverted signals generated after the photodetection, the direction ambiguity of the DFS is canceled out. The AOA can be instantaneously calculated through two downconverted signals via a Hilbert transform. Experimental results verify that a -77.90° to 77.90° AOA measurement with errors of less than ±1° is implemented, and a DFS measurement with errors of no more than ±3.1 Hz is also realized. Our proposed method not only removes the direction ambiguities of both DFS and AOA, but also avoids the dependence on echo signal power in AOA measurement, which largely increases the feasibility in realistic applications.

4.
Bioorg Chem ; 138: 106603, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37210825

RESUMO

Viscosity and peroxynitrite (ONOO-) are two significant indicators to affect and evaluate the mitochondrial functional status, which are nearly relational with pathophysiological process in many diseases. Developing suitable analytical methods for monitoring mitochondrial viscosity changes and ONOO- is thus of great importance. In this research, a new mitochondria-targeted sensor DCVP-NO2 for the dual determination of viscosity and ONOO- was exploited based on the coumarin skeleton. DCVP-NO2 displayed a red fluorescence "turn-on" response toward viscosity along with about 30-fold intensity increase. Meanwhile, it could be used as ratiometric probe for detection of ONOO- with excellent sensitivity and extraordinary selectivity for ONOO- over other chemical and biological species. Moreover, thanks to its good photostability, low cytotoxicity and ideal mitochondrion-targeting capability, DCVP-NO2 was successfully utilized for fluorescence imaging of viscosity variations and ONOO- in mitochondria of living cells through different channels. In addition, the results of cell imaging revealed that ONOO- would lead to the increase of viscosity. Taken together, this work provides a potential molecular tool for researching biological functions and interactions of viscosity and ONOO- in mitochondria.


Assuntos
Corantes Fluorescentes , Ácido Peroxinitroso , Corantes Fluorescentes/química , Ácido Peroxinitroso/análise , Dióxido de Nitrogênio/análise , Viscosidade , Mitocôndrias/química
5.
Phytother Res ; 37(4): 1293-1308, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36751854

RESUMO

Citrus peel has long been used in traditional medicine in Asia to treat common cold, dyspepsia, cough, and phlegm. Narirutin-a flavanone-7-O-glycoside-is the major flavonoid in citrus peel, and has anti-oxidative, anti-allergic, and anti-inflammatory activities. However, the anti-inflammatory mechanism of narirutin has not been fully elucidated. This study is aimed to investigate the effects of narirutin on the Nod-like receptor protein 3 (NLRP3)-mediated inflammatory response in vitro and in vivo, and determine the underlying mechanism. THP-1 differentiated macrophages and bone marrow-derived macrophages (BMDMs) were used for in vitro experiments, while dextran sulfate sodium (DSS)-induced colitis and alum-induced peritonitis mouse models were constructed to test inflammation in vivo. Narirutin suppressed secretion of interleukin (IL)-1ß and pyroptosis in lipopolysaccharide (LPS)/ATP-stimulated macrophages. Narirutin decreased the expression of NLRP3 and IL-1ß in the LPS-priming step through inhibition of NF-κB, MAPK and PI3K /AKT signaling pathways. Narirutin inhibited NLRP3-ASC interaction to suppress NLRP3 inflammasome assembly. Furthermore, oral administration of narirutin (300 mg/kg) alleviated inflammation symptoms in mice with peritonitis and colitis. These results suggest that narirutin exerts its anti-inflammatory activity by suppressing NLRP3 inflammasome activation via inhibition of the NLRP3 inflammasome priming processes and NLRP3-ASC interaction in macrophages.


Assuntos
Colite , Flavanonas , Peritonite , Animais , Camundongos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos , Flavanonas/farmacologia , Colite/induzido quimicamente , Inflamação/metabolismo , Anti-Inflamatórios/farmacologia , Peritonite/metabolismo
6.
Angew Chem Int Ed Engl ; 62(13): e202300008, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36734176

RESUMO

Cyclopentadiene (CPD) and methylcyclopentadiene (MCPD) are important intermediates that have been widely used in the production of high-energy-density rocket fuels, polymers and valuable chemicals. Currently, CPD and MCPD are produced from fossil energies at very low yields, which greatly limits their application. As a solution to this problem, we disclose an alternative two-step bio-route to access CPD and MCPD using xylose or extracted hemicellulose as the feedstock. In the first step, cyclopentanone (CPO) was directly produced by the selective hydrogenolysis of xylose or extracted hemicellulose over a commercial Ru/C catalyst in an acid-free toluene/NaCl aqueous solution biphasic system. In the second step, CPO was selectively converted to CPD by a cascade hydrodeoxygenation/dehydrogenation reaction over zinc molybdate catalysts. When methanol was introduced with CPO and hydrogen, MCPD was selectively obtained by a cascade dehydrogenation/aldol condensation/selective hydrodeoxygenation reaction over zinc molybdate catalysts.

7.
Opt Lett ; 47(18): 4750-4753, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107081

RESUMO

We propose a microwave photonic temperature interrogation system with high resolution and sensitivity based on temperature-to-time mapping with a simple structure. In this work, a bidirectional chirped optical signal is constructed, and the temperature information is mapped to the time interval change of the output pulses by filtering the bidirectional chirped optical signal using the transmission spectrum of a Fabry-Perot filter. Only a low-speed oscilloscope is required to extract the time interval of the output pulses in the proposed scheme, and complex data processing as well as synchronizing processes are avoided. In a proof-of-concept experiment, a high temperature interrogation sensitivity of 18.24 µs/°C and a high resolution of 0.035°C are realized, demonstrating good potential for practical applications.

8.
Appl Opt ; 61(36): 10700-10706, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606929

RESUMO

A radio-over-fiber (RoF) link with high spectral efficiency using digital phase cancellation is proposed and experimentally verified. The link can be utilized to transmit four microwave vector signals. The four microwave vector signals are modulated on optical signals by using a dual-polarization dual-parallel Mach-Zehnder modulator at the transmitter. The optical signals subsequently pass through a spool of single-mode fiber (SMF) and are sent into a coherent receiver. A digital signal processing (DSP) algorithm is proposed to eliminate the phase noise and frequency difference caused by two free-running lasers at transmitter and receiver. Two 16-quadrature amplitude modulation (16-QAM) vector signals at 6 GHz and another two 16-QAM vector signals at 7 GHz transmit over a 10-km SMF and are successfully recovered after a DSP algorithm. In order to evaluate the transmission performance of the RoF link, error vector magnitudes and bit error rates are also estimated.

9.
Angew Chem Int Ed Engl ; 61(4): e202113471, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34850519

RESUMO

PCTA is an important copolyester that has been widely used in our daily necessities. Currently, its monomers are industrially produced from petroleum-derived xylene. To reduce the reliance on fossil energy, we herein disclose an alternative route to access PCTA monomer (terephthalate/isophthalate=2.4/1) in 61 % overall yield using plant-based acrylate and acetaldehyde as the feedstocks. The process includes Morita-Baylis-Hillman (MBH) reaction of acetaldehyde with acrylate, subsequent one-step dehydration/Diels-Alder reaction with acrylate over H2 SO4 /SiO2 catalyst, and final Pd/C-catalyzed dehydrogenation. Besides, when varying the final step to hydrogenation, another important monomer UNOXOL™ diol (1,4-trans/1,4-cis/1,3-trans/1,3-cis=5.2/2/2.5/1) can be produced in 67 % overall yield.

10.
Opt Express ; 29(13): 19515-19524, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34266060

RESUMO

We propose and experimentally demonstrate a microwave frequency measurement system based on the photonic technique. An amplitude comparison function is constructed to perform frequency-to-power mapping based on a non-sliced broadband optical source. The results are fed into a machine learning module which can be utilized to minimize the differential mode noise of the system caused by the polarization fluctuation. The system is reconfigurable with adjustable measurement bandwidth by adjusting the dispersion group delay of the signals at orthogonal polarizations by a polarization division multiplexed emulator (PDME). In addition, the mapping relationship is reconstructed by stacking method. The results are fed into four machine learning models: support vector regressor (SVR), KNeighbors regressor (KNN), polynomial regressor (PR) and random forest regressor (RFR). The output of the four models then combined by adding them together using linear regression method. By fitting the relationship between frequency and microwave power ratio with machine learning method, the accuracy of microwave frequency measurement system is further improved. The results show that for a measurement system with a bandwidth of 2 GHz and 4 GHz, the maximum error and the average measurement errors are all reduced. The results are promising for applications of modern radar and electronic warfare systems.

11.
Biomarkers ; 26(4): 335-342, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33617373

RESUMO

PURPOSE: Dyslipidemia is an emerging metabolic disorder among pesticide-exposed agricultural workers, and this study was aimed to explore biomarkers of hypertriglyceridaemia susceptibility. METHODS: This cross-sectional study recruited 72 pesticide-exposed subjects and 78 non-exposed controls. Lipid profile, cholinesterase activity, and thyroid hormones were analysed with routine assays. Six loci, including rs11206244 and rs2235544 for deiodinase 1, rs12885300 and rs225014 for deiodinase 2, rs1803274 for butyrylcholinesterase, and rs3757869 for acetylcholinesterase were genotyped using an improved multiplex ligation detection reaction technique. RESULTS: Pesticide-exposed subjects showed higher levels of triglyceride than controls (p = 0.009), although there were comparable cholinesterase activity and genotype frequencies of all six loci between pesticide-exposed subjects and controls. Pesticide-exposed subjects with homozygous genotype of cholinesterase had increased triglyceride levels than controls (p < 0.05). The percentage of hypertriglyceridaemia was 28.6% and 8.8% for pesticide-exposed subjects and controls with homozygous butyrylcholinesterase genotype (p = 0.007) and 20.8% and 14.3% with homozygous acetylcholinesterase genotype (p = 0.792), respectively. Multivariate logistic regression analyses found that odds ratio of hypertriglyceridaemia is 21.92 and 4.56 for pesticide-exposed subjects with homozygous genotype of butyrylcholinesterase (p = 0.001) and acetylcholinesterase (p = 0.036), respectively. CONCLUSIONS: Cholinesterase homozygous genotype might be a potential susceptible biomarker in screening pesticide-exposed agricultural workers vulnerable to hypertriglyceridaemia.


Assuntos
Acetilcolinesterase/genética , Butirilcolinesterase/genética , Predisposição Genética para Doença/genética , Hipertrigliceridemia/genética , Exposição Ocupacional/efeitos adversos , Praguicidas/intoxicação , Polimorfismo de Nucleotídeo Único , Adulto , Agricultura , Alelos , Biomarcadores/metabolismo , Estudos Transversais , Fazendeiros/estatística & dados numéricos , Feminino , Frequência do Gene , Genótipo , Homozigoto , Humanos , Hipertrigliceridemia/diagnóstico , Hipertrigliceridemia/etiologia , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise
12.
Appl Opt ; 60(36): 11217-11221, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-35201111

RESUMO

We report a photonic-assisted radio frequency self-interference cancellation (RF-SIC) and frequency down-conversion scheme based on a dual-polarization Mach-Zehnder modulator (DP-MZM) by using a polarization manipulation method. In the proposed scheme, the self-interference signal is directly canceled in the optical domain by simply controlling the polarization states between the output of the DP-MZM and the polarizer. Frequency down-conversion is achieved by optoelectronic frequency mixing. In the proof-of-concept experiment, the interference cancellation of the single-frequency signal and wideband signal was conducted. The proposed RF-SIC and frequency down-conversion system has flexible tunability, simple structure, and low cost, which can find potential applications in radio-over-fiber systems.

13.
Ann Rheum Dis ; 79(6): 811-818, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32269059

RESUMO

OBJECTIVES: Obesity is a well-recognised risk factor for osteoarthritis (OA). Our aim is to characterise body mass index (BMI)-associated pathological changes in the osteochondral unit and determine if obesity is the major causal antecedent of early joint replacement in patients with OA. METHODS: We analysed the correlation between BMI and the age at which patients undergo total knee replacement (TKR) in 41 023 patients from the Australian Orthopaedic Association National Joint Replacement Registry. We then investigated the effect of BMI on pathological changes of the tibia plateau of knee joint in a representative subset of the registry. RESULTS: 57.58% of patients in Australia who had TKR were obese. Patients with overweight, obese class I & II or obese class III received a TKR 1.89, 4.48 and 8.08 years earlier than patients with normal weight, respectively. Microscopic examination revealed that horizontal fissuring at the osteochondral interface was the major pathological feature of obesity-related OA. The frequency of horizontal fissure was strongly associated with increased BMI in the predominant compartment. An increase in one unit of BMI (1 kg/m2) increased the odds of horizontal fissures by 14.7%. 84.4% of the horizontal fissures were attributable to obesity. Reduced cartilage degradation and alteration of subchondral bone microstructure were also associated with increased BMI. CONCLUSIONS: The key pathological feature in OA patients with obesity is horizontal fissuring at the osteochondral unit interface. Obesity is strongly associated with a younger age of first TKR, which may be a result of horizontal fissures.


Assuntos
Cartilagem Articular/patologia , Obesidade/complicações , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/patologia , Tíbia/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho , Índice de Massa Corporal , Epífises/patologia , Feminino , Humanos , Peso Corporal Ideal , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia
14.
Opt Lett ; 45(22): 6190-6193, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-33186947

RESUMO

We report a photonic scheme to generate multiband and multi-format microwave signals based on a commercial dual-polarization Mach-Zehnder modulator (DP-MZM). The key novelty of this work is the compact signal generator benefitting from the single modulator and the flexible multi-format signals at the multiband. The upper Mach-Zehnder modulator (MZM) of the DP-MZM is used to generate an optical frequency comb, while the lower MZM is driven by baseband electrical coding or single-chirp signal to obtain the multi-format modulated optical signal. The proposed scheme is theoretically analyzed and experimentally demonstrated. A multiband phase-coded microwave signal with a bit rate of 2 Gb/s and complementary linearly chirped microwave waveform pairs with a time duration of 1 µs and a bandwidth of 2 GHz have been successfully generated. The performance of pulse compression of generated signals is also demonstrated.

15.
BMC Infect Dis ; 20(1): 837, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183253

RESUMO

PURPOSES: Surgical site infection (SSI) after colorectal surgery is a frequent complication associated with the increase in morbidity, medical expenses, and mortality. To date, there is no nationwide large-scale database of SSI after colorectal surgery in China. The aim of this study was to determine the incidence of SSI after colorectal surgery in China and to further evaluate the related risk factors. METHODS: Two multicenter, prospective, cross-sectional studies covering 55 hospitals in China and enrolling adult patients undergoing colorectal surgery were conducted from May 1 to June 30 of 2018 and the same time of 2019. The demographic and perioperative characteristics were collected, and the main outcome was SSI within postoperative 30 days. Multivariable logistic regressions were conducted to predict risk factors of SSI after colorectal surgery. RESULTS: In total, 1046 patients were enrolled and SSI occurred in 74 patients (7.1%). In the multivariate analysis with adjustments, significant factors associated with SSI were the prior diagnosis of hypertension (OR, 1.903; 95% confidence interval [CI], 1.088-3.327, P = 0.025), national nosocomial infection surveillance risk index score of 2 or 3 (OR, 3.840; 95% CI, 1.926-7.658, P < 0.001), laparoscopic or robotic surgery (OR, 0.363; 95% CI, 0.200-0.659, P < 0.001), and adhesive incise drapes (OR, 0.400; 95% CI, 0.187-0.855, P = 0.018). In addition, SSI group had remarkably increased length of postoperative stays (median, 15.0 d versus 9.0d, P < 0.001), medical expenses (median, 74,620 yuan versus 57,827 yuan, P < 0.001), and the mortality (4.1% versus 0.3%, P = 0.006), compared with those of non-SSI group. CONCLUSION: This study provides the newest data of SSI after colorectal surgery in China and finds some predictors of SSI. The data presented in our study can be a tool to develop optimal preventive measures and improve surgical quality in China.


Assuntos
Cirurgia Colorretal/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Idoso , China/epidemiologia , Infecção Hospitalar/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Incidência , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
16.
J Cell Mol Med ; 23(8): 5782-5793, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31225702

RESUMO

Osteoporosis has become a worldwide problem as the population ages. Although many advances have been made in the treatment of osteoporosis in the past few years, the outcome are sometimes disturbing because of the adverse effects of these treatments. Further studies are still needed to identify novel alternate agents to improve the therapeutic effect. Ginkgolide B (GB), a derivative of Ginkgo biloba leaves, has numerous pharmacological effects, including anticancer and anti-inflammation activities. However, the effect of GB on the regulation of osteoblast activity and bone formation effect has not yet been investigated. In this study, we showed the in vitro and in vivo effects of GB on osteoblast differentiation and bone formation. We found that GB promotes osteoblast differentiation of Bone Mesenchymal Stem Cells (BMSCs) and MC3T3-E1 cells in vitro in a Wnt/ß-catenin-dependent manner. In an in vivo study, we constructed a cranial defect model in rats and treated with GB. Histomorphometric and histological analyses confirmed that the usage of GB significantly promotes bone formation. Further study on ovariectomy (OVX) rats demonstrated that GB is capable of alleviating ovariectomy-induced bone loss by enhancing osteoblast activity. Our findings indicate that GB is a potential therapeutic agent of osteoporosis through an anabolic way in bone.


Assuntos
Osso e Ossos/patologia , Diferenciação Celular/efeitos dos fármacos , Ginkgolídeos/farmacologia , Lactonas/farmacologia , Osteoblastos/metabolismo , Osteoblastos/patologia , Osteoporose/patologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Osso e Ossos/efeitos dos fármacos , Linhagem Celular , Masculino , Camundongos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ovariectomia , Ratos Sprague-Dawley , beta Catenina/metabolismo
17.
Angew Chem Int Ed Engl ; 58(35): 12154-12158, 2019 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-31245892

RESUMO

The synthesis of renewable jet fuel from lignocellulosic platform compounds has drawn a lot of attention in recent years. So far, most work has concentrated on the production of conventional jet fuels. JP-10 is an advanced jet fuel currently obtained from fossil energy. Due to its excellent properties, JP-10 has been widely used in military aircraft. However, the high price and low availability limit its application in civil aviation. Here, we report a new strategy for the synthesis of bio-JP-10 fuel from furfuryl alcohol that is produced on an industrial scale from agricultural and forestry residues. Under the optimized conditions, bio-JP-10 fuel was produced with high overall carbon yields (≈65 %). A preliminary economic analysis indicates that the price of bio-JP-10 fuel can be greatly decreased from ≈7091 US$/ton (by fossil route) to less than 5600 US$/ton using our new strategy. This work makes the practical application of bio-JP-10 fuel forseeable.

18.
Mol Pharmacol ; 93(4): 368-375, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29436491

RESUMO

Angiogenesis in atherosclerotic plaque promotes plaque growth, causes plaque hemorrhage, and violates plaque stability. LINC00657 is a long noncoding RNA highly conserved and abundantly expressed in vascular endothelial cells. The present study was designed to investigate the effects and mechanisms of LINC00675 on low concentrations of oxidized low-density lipoprotein (oxLDL)-induced angiogenesis. Cell proliferation, transwell, wound healing, and tube formation assays were conducted to detect the effects of low concentrations of oxLDL on angiogenesis; the results discovered that oxLDL promoted cell proliferation, migration, and tube formation. oxLDL also upregulated LINC00657 expression. Inhibition of LINC00657 by siRNA significantly suppressed oxLDL-induced endothelial cell proliferation, migration, and tube formation. Bioinformatic assay indicated six binding sites in the LINC00657 sequence to miR-590-3p. The upregulation of LINC00657 was related to the downregulation of miR-590-3p in oxLDL-treated endothelial cells; while downregulation of LINC00657 resulted in upregulation of miR-590-3p. The antiangiogenesis effects of si-LINC00657 were partly abrogated by miR-590-3p inhibitor. Further dual-luciferase assay found miR-590-3p inhibited the expression of hypoxia-inducible factor 1α (HIF-1α) by binding to the position of 689-696 in HIF-1α 3'-untranslated region directly. MiR-590-3p also inhibited the oxLDL-induced upregulation of HIF-1α, vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-9 (MMP-9). These results suggested that in oxLDL-treated endothelial cells, LINC00657 acted as a miR-590-3p sponge to attenuate the suppression of miR-590-3p on HIF-1α, and to promote angiogenesis through VEGF, MMP-2, and MMP-9. The present study provided new insight into the roles of LINC00657 and miR-590-3p in preventing oxLDL-induced angiogenesis and may provide a novel strategy for atherosclerosis treatment.


Assuntos
Indutores da Angiogênese/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , MicroRNAs/biossíntese , RNA Longo não Codificante/biossíntese , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , MicroRNAs/genética , Oxirredução/efeitos dos fármacos , RNA Longo não Codificante/genética
19.
Angew Chem Int Ed Engl ; 57(23): 6901-6905, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29673054

RESUMO

Valuable polyester monomers and plasticizers-1,4-cyclohexanedimethanol (CHDM), 1,4-cyclohexanedicarboxylic acid (CHDA), and 1,2-cyclohexanedicarboxylates-have been prepared by a new strategy. The synthetic processes involve a proline-catalyzed formal [3+1+2] cycloaddition of formaldehyde, crotonaldehyde, and acrylate (or fumarate). CHDM is produced after a subsequent hydrogenation step over a commercially available Cu/Zn/Al catalyst and a one-pot hydrogenation/oxidation/hydrolysis process yields CHDA, whereas 1,2-cyclohexanedicarboxylate is obtained by a Pd/C-catalyzed tandem decarbonylation/hydrogenation step.

20.
Mediators Inflamm ; 2016: 5308170, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27403035

RESUMO

Objective. The present study was performed to investigate the effects and mechanisms of miR-99a on LPS-induced endothelial cell inflammation, as well as the regulation of NF-κB on miR-99a production. Methods and Results. ELISA showed that LPS treatment significantly promoted the secretion of inflammatory factors (TNF-α, IL-6, IL-1ß, and MCP-1). LPS treatment also inhibited miR-99a production and promoted mTOR expression and NF-κB nuclear translocation. Overexpression of miR-99a suppressed the LPS-induced TNF-α, IL-6, IL-1ß, and MCP-1 overproduction, mTOR upregulation, and NF-κB nuclear translocation. The PROMO software analysis indicated NF-κB binding site in the -1643 to -1652 region of miR-99a promoter. Dual luciferase reporter analysis, electrophoretic mobility shift assays (EMSA), and chromosome immunoprecipitation (ChIP) assays demonstrated that NF-κB promoted the transcription of miR-99a by binding to the -1643 to -1652 region of miR-99a promoter. Further studies on HUVECs verified the regulatory effects of NF-κB on miR-99a production. Conclusion. MiR-99a inhibited the LPS-induced HUVECs inflammation via inhibition of the mTOR/NF-κB signal. NF-κB promoted miR-99a production by binding to the -1643 to -1652 region of miR-99a promoter. Considering the importance of endothelial inflammation on cardiovascular diseases, such as atherosclerosis, our results may provide a new insight into the pathogenesis and therapy of atherosclerosis.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Sítios de Ligação , Quimiocina CCL2/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Ensaio de Imunoadsorção Enzimática , Células HEK293 , Histonas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , MicroRNAs/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
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