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1.
Opt Lett ; 48(11): 2973-2976, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262257

RESUMO

A high sensitivity optical fiber temperature and gas pressure sensor with integrated micro-cavity is proposed. First, a single-mode optical fiber (SMF) is spliced with a section of capillary, and then the sensitive material polydimethylsiloxane (PDMS) is filled into the capillary to form a Fabry-Perot interferometer (FPI). Finally, a femtosecond laser is used to ablate the fiber core of the SMF to form the third reflecting surface, constituting two cascaded FPIs. When two FPIs have a similar free spectral range, a Vernier effect is produced. The temperature and gas pressure sensitivity of the sensor reached 14.41 nm/°C and 113.82 nm/MPa, respectively, after using the sensitive material and Vernier effect double sensitization technology. In addition, a fiber Bragg grating is cascaded with the sensor, which can realize the simultaneous measurement of temperature and gas pressure and eliminate cross-sensitivity.

2.
Opt Lett ; 48(7): 1674-1677, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221738

RESUMO

An ultra-sensitive sensor, based on two Fabry-Perot interferometers (FPIs), has been realized for temperature and pressure sensing. A polydimethylsiloxane (PDMS)-based FPI1 was used as a sensing cavity, and a closed capillary-based FPI2 was used as a reference cavity for its insensitivity to both temperature and pressure. The two FPIs were connected in series to obtain a cascaded FPIs sensor, showing a clear spectral envelope. The temperature and pressure sensitivities of the proposed sensor reach up to 16.51 nm/°C and 100.18 nm/MPa, which are 25.4 and 21.6 times, respectively, larger than these of the PDMS-based FPI1, showing a great Vernier effect.

3.
Appl Opt ; 62(2): 275-283, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36630225

RESUMO

In this paper, an enhanced Vernier effect temperature sensor based on two parallel Fabry-Perot interferometers (FPIs) is proposed and demonstrated experimentally. Among them, F P I 1 is composed of a single-mode fiber (SMF), a quartz capillary, and AB glue filled in the capillary. F P I 2 is formed by filling a capillary with polyimide (PI) solution and inserting two-segment SMF from both sides of the capillary. Since AB glue and PI have good thermal sensitivity, F P I 1 and F P I 2 are highly sensitive to temperature. Due to their different structures, the temperature sensitivity of F P I 1 is negative, and that of F P I 2 is positive. When F P I 1 and F P I 2 with similar free spectral range are connected in parallel, they will act as reference cavities for each other, resulting in an enhanced Vernier effect, which enlarges the sensitivity of the sensor more. In the temperature range of 40°C-58°C, the temperature sensitivity of the sensor is as high as -13.09n m/∘ C, and the fitting coefficient is 0.9974. The experimental results show that in the enhanced Vernier effect sensor structure, only two FPIs with opposite temperature sensitivity are required, which does not increase the difficulty and cost of sensor manufacturing. In addition, the sensor has good stability and repeatability.

4.
Opt Express ; 30(19): 34956-34972, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36242499

RESUMO

A high sensitivity optical fiber gas pressure sensor based on the enhanced Vernier effect is proposed. The sensor is composed of a fiber Fabry-Perot interferometer (FPI) and Mach-Zehnder interferometer (MZI). Since the interference fringes of FPI and MZI drift in the opposite direction with the change of gas pressure, when their free spectral ranges are similar, the enhanced Vernier effect is formed after their cascading. Compared with the traditional Vernier effect gas pressure sensor, the enhanced Vernier effect gas pressure sensor realizes much higher sensitivity gas pressure measurement without complex manufacturing process or desensitized reference interferometer. The experimental results show that the sensitivity of the enhanced Vernier effect sensor is 241.87 nm/MPa. In the two traditional Vernier effect gas pressure sensors formed by cascading FPI and MZI, the sensitivity of sensor is 63.02 nm/MPa and 171.26 nm/MPa, respectively. Compared with the two traditional Vernier effect sensors, the sensitivity of the enhanced Vernier effect sensor is increased by 3.8 times and 1.4 times, respectively. The proposed sensor also has the advantages of good repeatability and stability, fast response, low cost and easy manufacture. Our structure also provides a new design scheme for a high sensitivity optical fiber gas pressure sensor.

5.
Bioorg Chem ; 124: 105813, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35447405

RESUMO

A series of dihydrotriazine derivatives bearing 5-aryloxypyrazole moieties were designed, and their anticancer activities against three human cancer cell lines (SGC-7901, HepG-2 and MCF-7) and one non-cancer cell line (LO2) were explored using the MTT assay in vitro. Most of the compounds exhibited potent antiproliferative activities against the three cancer cell lines, with compound 10e (IC50 = 2.12 µM) exhibiting the most potent antiproliferative activity against HepG-2 cells. Interestingly, autophagy was observed in the 10e-treated HepG-2 cells. Compound 10e also increased reactive oxygen species (ROS) levels and resulted in marked HepG-2 cells apoptosis. Further studies revealed that compound 10e could enhance the expression of Cl-PARP, Cl-caspase-3, and Cl-caspase-9. In addition, 10e triggered the formation of autophagosomes by promoting LC3-II and Beclin-1 expression. These results might be useful for exploring and developing dihydrotriazine derivatives as novel anticancer agents.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
6.
Mol Divers ; 26(2): 1129-1139, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34080112

RESUMO

In order to discover novel anti-inflammatory agents, three series of compounds obtained by appending 1,2,3-triazole moieties on ursolic acid were designed and synthesized. All compounds have been screened for their anti-inflammatory activity by using an ear edema model. The potent anti-inflammatory compound was subjected to in vitro cyclooxygenase COX-1/COX-2 inhibition assays. In general, the derivatives were found to be potent anti-inflammatory activity. Especially, the compound 11b exhibited the strongest activity of all of the compounds prepared, with 82.81% inhibition after intraperitoneal administration, which was better than celecoxib as a positive control. Molecular docking results unclose the rationale for the interaction of the compound 11b with COX-2 enzyme. Further studies revealed that compound 11b exhibited effective COX-2 inhibitory activity, with half-maximal inhibitor concentration (IC50) value of 1.16 µM and selectivity index (SI = 64.66) value close to that of celecoxib (IC50 = 0.93 µM, SI = 65.47). Taken together, these results could suggest a promising chemotype for development of new COX-2-targeting anti-inflammatory agent.


Assuntos
Inibidores de Ciclo-Oxigenase 2 , Triazóis , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Celecoxib/farmacologia , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Relação Dose-Resposta a Droga , Desenho de Fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/farmacologia , Triterpenos , Ácido Ursólico
7.
J Cell Mol Med ; 23(4): 2801-2812, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30734467

RESUMO

Here, we report that LMK235, a class I and histone deacetylase (HDAC6)-preferential HDAC inhibitor, reduces hypertension via inhibition of vascular contraction and vessel hypertrophy. Angiotensin II-infusion mice and spontaneously hypertensive rats (SHRs) were used to test the anti-hypertensive effect of LMK235. Daily injection of LMK235 lowered angiotensin II-induced systolic blood pressure (BP). A reduction in systolic BP in SHRs was observed on the second day when SHRs were treated with 3 mg/kg LMK235 every 3 days. However, LMK235 treatment did not affect angiotensin-converting enzyme 1 and angiotensin II receptor mRNA expression in either hypertensive model. LMK235, acting via the nitric oxide pathway, facilitated the relaxing of vascular contractions induced by a thromboxane A2 agonist in the rat aortic and mesenteric artery ring test. In addition, LMK235 increased nitric oxide production in HUVECs and inhibited the increasing of aortic wall thickness in both animal hypertensive models. LMK235 decreased the enhanced cell cycle-related genes cyclin D1 and E2F3 in angiotensin II-infusion mice and restored the decreased p21 expression. In addition, LMK235 suppressed calcium calmodulin-dependent protein kinase II (CaMKII) α, which is related to vascular smooth muscle cell proliferation. Inhibition or knockdown of HDAC5 blocked the CaMKIIα-induced cell cycle gene expression. Immunoprecipitation demonstrated that class I HDACs were involved in the inhibition of CaMKII α-induced HDAC4/5 by LMK235. We suggest that LMK235 should be further investigated for its use in the development of new therapeutic options to treat hypertension via reducing vascular hyperplasia or vasoconstriction.


Assuntos
Anti-Hipertensivos/farmacologia , Doenças da Aorta/tratamento farmacológico , Benzamidas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão/complicações , Vasoconstrição/efeitos dos fármacos , Angiotensina II/toxicidade , Animais , Doenças da Aorta/etiologia , Doenças da Aorta/patologia , Inibidores de Histona Desacetilases/farmacologia , Hipertensão/induzido quimicamente , Hipertensão/patologia , Masculino , Camundongos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley
8.
J Cell Mol Med ; 22(12): 5964-5977, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30256522

RESUMO

We previously reported that gentisic acid (2,5-dihydroxybenzoic acid) is the third most abundant phenolic component of Dendropanax morbifera branch extracts. Here, we investigated its effects on cardiac hypertrophy and fibrosis in a mouse model of pressure overload and compared them to those of the beta blocker bisoprolol and calcium channel blocker diltiazem. Cardiac hypertrophy was induced in mice by transverse aortic constriction (TAC). Beginning 2 weeks after this procedure, the mice were given daily intraperitoneal injections of gentisic acid (100 mg/kg/d), bisoprolol (5 mg/kg/d) or diltiazem (10 mg/kg/d) for 3 weeks. Cardiac hypertrophy was evaluated by the heart weight-to-body weight ratio, the cardiomyocyte cross-sectional area after haematoxylin and eosin staining, and echocardiography. Markers of cardiac hypertrophy and fibrosis were tested by reverse transcription-quantitative real-time polymerase chain reaction, western blotting and Masson's trichrome staining. The suppressive effects of gentisic acid treatment on TAC-induced cardiac hypertrophy and fibrosis were comparable to those of bisoprolol administration. Cardiac hypertrophy was reversed and left ventricular septum and posterior wall thickness were restored by gentisic acid, bisoprolol and diltiazem treatment. Cardiac hypertrophic marker gene expression and atrial and brain natriuretic peptide levels were decreased by gentisic acid and bisoprolol, as were cardiac (interstitial and perivascular) fibrosis and fibrosis-related gene expression. Cardiac hypertrophy-associated upregulation of the transcription factors GATA4 and Sp1 and activation of extracellular signal-regulated kinase 1/2 were also negated by these drugs. These results suggest that gentisic acid could serve as a therapeutic agent for cardiac hypertrophy and fibrosis.


Assuntos
Cardiomegalia/tratamento farmacológico , Cardiomegalia/enzimologia , Gentisatos/uso terapêutico , Sistema de Sinalização das MAP Quinases , Miocárdio/patologia , Pressão , Animais , Aorta/patologia , Cardiomegalia/genética , Cardiomegalia/patologia , Constrição Patológica , Eletrocardiografia , Fibrose , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Gentisatos/farmacologia , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo
9.
J Cell Mol Med ; 22(3): 1517-1526, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29266709

RESUMO

Hypertension causes cardiac hypertrophy and leads to heart failure. Apoptotic cells are common in hypertensive hearts. Ca2+ /calmodulin-dependent protein kinase II (CaMKII) is associated with apoptosis. We recently demonstrated that gallic acid reduces nitric oxide synthase inhibition-induced hypertension. Gallic acid is a trihydroxybenzoic acid and has been shown to have beneficial effects, such as anti-cancer, anti-calcification and anti-oxidant activity. The purpose of this study was to determine whether gallic acid regulates cardiac hypertrophy and apoptosis in essential hypertension. Gallic acid significantly lowered systolic and diastolic blood pressure in spontaneously hypertensive rats (SHRs). Wheat germ agglutinin (WGA) and H&E staining revealed that gallic acid reduced cardiac enlargement in SHRs. Gallic acid treatment decreased cardiac hypertrophy marker genes, including atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), in SHRs. The four isoforms, α, ß, δ and γ, of CaMKII were increased in SHRs and were significantly reduced by gallic acid administration. Gallic acid reduced cleaved caspase-3 protein as well as bax, p53 and p300 mRNA levels in SHRs. CaMKII δ overexpression induced bax and p53 expression, which was attenuated by gallic acid treatment in H9c2 cells. Gallic acid treatment reduced DNA fragmentation and the TUNEL positive cells induced by angiotensin II. Taken together, gallic acid could be a novel therapeutic for the treatment of hypertension through suppression of CaMKII δ-induced apoptosis.


Assuntos
Anti-Hipertensivos/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cardiotônicos/farmacologia , Ácido Gálico/farmacologia , Hipertensão/tratamento farmacológico , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Angiotensina II/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Regulação da Expressão Gênica , Hipertensão/enzimologia , Hipertensão/genética , Hipertensão/patologia , Hipertrofia Ventricular Esquerda/enzimologia , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/patologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Fatores de Transcrição de p300-CBP/genética , Fatores de Transcrição de p300-CBP/metabolismo
10.
Photochem Photobiol Sci ; 14(4): 853-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25694154

RESUMO

Quaterthiophene is used as a fluorescent marker for biological applications, but the intrinsic excited state dynamics for its high triplet-formation yield are still under debate due to the complexity of the molecule structure and the undetermined energy level order. In this work, ultrafast geometry relaxation and intersystem crossing of quaterthiophene in 1,4-dioxane are studied by femtosecond time-resolved spectroscopy combined with quantum calculations. Transient absorption spectra at a pump wavelength of 400 nm are completely recorded up to the delay time of 1 ns. The kinetic traces of excited state absorption indicate that geometry relaxation occurs on the S1 potential energy surface with a time constant of ∼70 ps. Two triplet-triplet absorption bands centered at 563 nm and 600 nm show a direct dynamical conversion. The intersystem crossing is determined to be ∼398 ps. The high triplet yield is measured as ∼0.7 via the efficient intersystem crossing. On the basis of quantum chemical calculations, a general mechanism is proposed to describe the geometry relaxation and intersystem crossing processes.

11.
J Cardiovasc Pharmacol Ther ; : 10742484241264673, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39033435

RESUMO

OBJECTIVE: This study evaluates the 3-year clinical outcomes of high Killip grade (III/IV) acute myocardial infarction (AMI) patients treated with either ß-blockers (BB) and angiotensin-converting enzyme inhibitors (ACEI) or BB and angiotensin receptor blockers (ARB). METHODS: A total of 13,105 patients were registered at the Korea Acute Myocardial Infarction Registry at the National Institute of Health (KAMIR-NIH). Among them, 871 patients with high Killip classification AMI were divided into the BB + ACEI group (n = 489) and the BB + ARB group (n = 381). Following propensity score matching, 343 patients were selected in each group. All patients completed a 3-year follow-up period. RESULTS: The results indicate no significant differences between the BB + ACEI group and BB + ARB group in terms of cardiac death, recurrent myocardial infarction, and the rate of repeat percutaneous coronary intervention. However, the BB + ACEI group exhibited significantly lower risks in major adverse cardiac events (HR = 0.574, 95% CI: 0.421-0.783, p < .001), all-cause mortality (HR = 0.561, 95% CI: 0.404-0.778, p = .001), and non-cardiac death (HR = 0.365, 95% CI: 0.208-0.639, p < .001) compared to the BB + ARB group. CONCLUSION: Our results suggest that BB + ACEI treatment is more beneficial than BB + ARB for high Killip grade AMI patients. Additionally, the BB + ACEI group has a superior preventative effect on mortality compared to the BB + ARB group.

12.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38456759

RESUMO

A hollow core fiber (HCF) is spliced with a single-mode fiber, and then, the end face of the HCF is etched to form a microsphere interferometer for measuring gas pressure and environmental temperature. The total length of each microsphere is less than 200 µm. We fabricated two such structures and used femtosecond laser pulses to drill micro-holes on the HCF walls of both structures. One of the structures is directly used to measure air pressure, achieving a sensitivity of up to 2.857 nm/MPa while being almost insensitive to temperature. This structure is capable of assessing pressure down to 3.4 kPa within the range of 0-0.5 MPa. Another structure is filled with thermally sensitive material dimethyl silicone oil through a micro-hole, and then, it is sealed with AB adhesive to form a harmonic Vernier effect temperature sensor, with a sensitivity of up to -5.16 nm/°C. This structure is capable of assessing temperature down to 0.38 °C within the range of 30-60 °C. Additionally, the sensors have good repeatability and stability and compact structure and simple manufacturing and can be used as a sensing probe for monitoring gas pressure and temperature under extreme environments.

13.
Am J Transl Res ; 15(5): 3639-3646, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303642

RESUMO

OBJECTIVE: To analyze the clinical effects and economic costs between Warfarin and novel oral anticoagulants in elderly patients with atrial fibrillation (AF). METHODS: This is a retrospective study. A total of 680 elderly AF patients receiving oral anticoagulants for the first time were selected as subjects and assigned into Group A, B and C. Patients in group A, B and C were given dabigatran etexilate, rivaroxaban and warfarin, respectively. Patients were followed up for 2 years. This study compared indicators of left ventricular diastolic function such as left ventricular posterior wall in end-diastole (LVPWd), minimum peak velocity in early diastole phase and maximum peak velocity in late diastole phase, indicators of myocardial ischemia including creatine kinase isoenzyme, lactate dehydrogenase (LDH) and myoglobin, as well as other outcomes including adverse events incidences and treatment costs, among the three groups. RESULTS: After treatment, LVPWd was found to be obviously lower in group A and group B than that in group C, while the minimum peak velocity in early diastole phase was markedly more in group A and B than that in group C (all P<0.05). In addition, the concentrations of myoglobin and LDH were significantly reduced in group A and B than those in group C (all P<0.05). The occurrence rate of adverse events was significantly lower in group A and B than that in group C (P<0.05). Moreover, treatment cost was markedly less in group A and B than that in group C (P<0.05). CONCLUSION: Compared with warfarin, dabigatran etexilate and rivaroxaban not only have the ability to inhibit the myocardial ischemia indicators and improve left ventricular diastolic function while reducing the incidence of adverse events, but they also offer certain cost-effectiveness advantages for elderly patients with AF.

14.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051177

RESUMO

Two different structures, long period fiber grating (LPFG) and a Mach-Zehnder interferometer (MZI), were cascaded to fabricate a sensor for sensing humidity and temperature simultaneously. Due to the humidity sensitive characteristic of polyimide (PI) and the temperature sensitive characteristic of polydimethylsiloxane (PDMS), the LPFG was coated with PI and the MZI was wrapped in PDMS to improve the humidity and temperature sensitivities, respectively. Humidity and temperature experiments and the stability and repeatability of the proposed sensors were performed. The sensor shows humidity and temperature sensitivities of ∼164 pm/%RH and 183 pm/°C in the humidity and temperature increasing experiments, respectively. Combining increasing, decreasing, and repeatable experiments of temperature and humidity, the proposed sensor shows stable performance in humidity sensitivity of ∼159 pm/%RH and temperature sensitivity of ∼175 pm/°C, with good linearity of ∼0.994. The structure of the proposed sensor has the advantages of low implementation cost, easy fabrication, and good stability.

15.
Chemosphere ; 332: 138782, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37142106

RESUMO

The compounds including furan-2,5-dicarboxylic acid (FDCA), 2-methyl-3-furoic acid (MFA), and 2-furoic acid (FA), containing Furan ring are considered to be possessing high ozone reactivity, although in depth studies of their ozonation processes have not been carried out yet. Hence, mechanism, kinetics and toxicity by quantum chemical, and their structure activity relationship are being investigated in this study. Studies of reaction mechanisms revealed that during the ozonolysis of three furan derivatives containing C=C double bond, furan ring opening occurs. At temperature (298 K) and pressure of 1 atm, the degradations rates of 2.22 × 103 M-1 s-1 (FDCA), 5.81 × 106 M-1 s-1 (MFA) and 1.22 × 105 M-1 s-1 (FA) suggested that the reactivity order is: MFA > FA > FDCA. In the presence of water, oxygen and ozone, the Criegee intermediates (CIs) as the primary products of ozonation would produce lower molecule weight of aldehydes and carboxylic acids by undergoing degradation pathways. The aquatic toxicity reveals that three furan derivatives play green chemicals roles. Significantly, most of the degradation products are least harmful to organisms residing in the hydrosphere. The mutagenicity and developmental toxicity of FDCA is minimum as compared to FA and MFA, which shows the applicability of FDCA in a wider and broader field. Results of this study reveal its importance in the industrial sector and degradation experiments.


Assuntos
Ozônio , Poluentes Químicos da Água , Oxirredução , Furanos/toxicidade , Água , Ozônio/química , Cinética , Modelos Teóricos , Poluentes Químicos da Água/análise
16.
Chemosphere ; 303(Pt 3): 135142, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35636604

RESUMO

In this study, we investigated the reaction mechanism and kinetics of ozone with trans-2-pentenal using density functional theory (DFT) and conventional transition state theory (CTST). At 298 K and 1 atm, the gas-phase reaction mechanisms and kinetic parameters were calculated at the level of CCSD(T)/6-311+G(d,p)//M06-2X/6-311+G(d,p). Both CC and CO bond cycloaddition as well as hydrogen abstraction were found. The calculations indicated that the main reaction path is 1,3-dipole cycloaddition reactions of ozone with CC bond with the relatively lower syn-energy-barrier of 3.35 kcal mol-1 to form primary ozonide which decomposed to produce a carbonyl oxide called a Criegee intermediate (CI) and an aldehyde. The subsequent reactions of CIs were analysed in detail. It is found that the reaction pathways of the novelty CIs containing an aldehyde group are extremely similar with general CIs when they react with NO, NO2, SO2, H2O, CH2O and O2. The condensed Fukui function were calculated to identify the active site of the chosen molecules. At 298 K and 1 atm, the reaction rate coefficient was 9.13 × 10-18 cm3 molecule-1 s-1 with atmospheric lifetime of 1.3 days. The calculated rate constant is in general agreement with the available experimental data. The branching ratios indicated that syn-addition pathways are prior to anti-addition. The atmospheric ratios for CIs formation and the bimolecular reaction rate constants for the Criegee intermediates with the variety of partners were calculated. Our theoretical results are of importance in atmospheric chemistry of unsaturated aldehyde oxidation by ozone.


Assuntos
Ozônio , Aldeídos , Cinética , Modelos Teóricos , Ozônio/química
17.
Autoimmunity ; 55(8): 661-669, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36226520

RESUMO

Gouty arthritis (GA) is mainly caused by the precipitation of monosodium urate (MSU) crystals in the joint. Recently, different regulatory roles of microRNAs (miRNAs) in arthritis have been widely verified. Nevertheless, the specific function of microRNA-486-5p (miR-486-5p) in GA is still unclear. GA cell models in vitro were established by the treatment of 250 µg/mL MSU crystals into THP-1 cells or J774A.1 cells. Then, the accumulation of tumor necrosis factor (TNF)-α, interleukin (IL)-8, and IL-ß was estimated by ELISA. The mRNA levels of TNF-α, IL-8, and IL-ß were measured through RT-qPCR. The protein level of forkhead box protein O1 (FOXO1) was tested via western blot. Furthermore, the interplay of miR-486-5p and FOXO1 was evaluated via the luciferase reporter assay. In this study, MSU treatment successfully stimulated the inflammatory response in macrophage cells. MiR-486-5p downregulation was observed in THP-1 and J774A.1 cells treated with MSU, and its upregulation markedly decreased the concentration and mRNA levels of TNF-α, IL-8, and IL-ß. Furthermore, FOXO1 was demonstrated to be negatively modulated by miR-486-5p. The rescue assay indicated that overexpressing FOXO1 reversed the effects of overexpressing miR-486-5p on inflammatory cytokines. Overall, this study proves that miR-486-5p inhibits GA inflammatory response via modulating FOXO1.


Assuntos
Artrite Gotosa , MicroRNAs , Artrite Gotosa/genética , Artrite Gotosa/metabolismo , Artrite Gotosa/patologia , Citocinas/metabolismo , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/farmacologia , Humanos , Interleucina-8 , Macrófagos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ácido Úrico/metabolismo , Ácido Úrico/farmacologia
18.
Rev Sci Instrum ; 93(8): 085002, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050096

RESUMO

In this paper, a highly sensitive optical fiber gas pressure sensor is proposed and experimentally verified. The sensor is composed of two Fabry-Pérot (F-P) cavities, and two F-P cavities are fabricated by a single-mode fiber and two quartz capillaries with different inner diameters splicing. Among them, the small inner diameter capillary is used as a gas channel connecting the large inner diameter capillary and the external environment. The manufacturing process of the sensor only involves capillary cleaver and splicing and does not involve other complex manufacturing technologies. By correctly adjusting the length of the two quartz capillaries, when the free spectral range of the two F-P cavities is very close, the optical Vernier effect will be observed and used as a sensitive probe for detecting gas pressure. The experimental results show that, in the pressure range of 0-0.8 MPa, the gas pressure sensitivity of the sensor reaches -81.73 nm/MPa with a linearity of 99.7%, and the temperature cross-sensitivity is only 1.82 kPa/°C. Due to its easy manufacture, high sensitivity, compact structure, and small volume, the sensor has become one of the preferred structures for large-scale use in the field of gas sensing.

19.
Artigo em Inglês | MEDLINE | ID: mdl-35911142

RESUMO

Purpose: Complete detachment of the medial collateral ligament (MCL) may occur during medial release of total knee arthroplasty (TKA) in patients with severe varus knee osteoarthritis. This study was to determine functional and stability outcomes of repaired knee with complete detachment of MCL compared to those of contralateral nondetached MCL in patients with bilateral TKA. Methods: Records of 1052 consecutive knees undergoing bilateral TKA from 2003 to 2015 were retrospectively reviewed. Of which, 45 patients were repaired for complete MCL detachment injury (2.1%) at tibial insertion in one side (repaired group). MCL was not detached in the contralateral side (control group). Clinical evaluation was performed preoperatively and at the final follow-up using KS and WOMAC scores between two groups. Similarly, stability was compared on a valgus stress radiograph between two groups. Results: Two patients had insufficient data. Hence, 43 patients were included after a minimum of 5 years follow-up. There were no significant differences in terms of alignment and clinical outcomes between the two groups either preoperatively or at the final follow-up (p > 0.05). Radiographic stability also showed no differences between repaired and control groups in extension and 30° of flexion (p=0.208 and p=0.125). Conclusions: For tibial detachment of the MCL during TKA, repair with suture anchor provided good clinical and stability results, similar to TKA without MCL injury. Therefore, repair with a suture anchor is a reliable method that provides good clinical and stability outcomes in patients with MCL injury during TKA.

20.
Rev Sci Instrum ; 92(12): 125003, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34972480

RESUMO

In this paper, a Mach-Zehnder interferometer temperature sensor with a single-mode fiber-thin-core fiber-single-mode fiber cascaded is designed. When the light is transmitted from the single-mode fiber to the thin-core fiber, different modes will be excited because of the mode-field mismatch. Optical power from the input fiber can be partly coupled to the cladding modes of the thin-core fiber, and the cladding modes of the thin-core fiber then re-coupled to the lead-out fiber, which constitutes the Mach-Zehnder interferometer in the output single-mode fiber. To improve the temperature sensitivity of the sensor, we coated the thermal-sensitive material (such as polymethoxane or ultraviolet glue) on the surface of the thin-core fiber. The experimental results show that the temperature sensitivity of the sensor coated with a polydimethylsiloxane film was increased from 32.0 to 90.0 pm/°C, about three times, compared to the uncoated thin-core fiber sensor. When the surface of the thin-core fiber is coated with an ultraviolet glue film, the temperature sensitivity of the sensor was increased from 32.0 to 166.8 pm/°C, about six times. The designed sensor, with compact structure, simple production, strong robustness, and high sensitivity, has a wide application prospect in industrial production and national defense technology.

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