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1.
Inorg Chem ; 63(17): 7746-7753, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38609344

RESUMO

A novel two-dimensional (2D) Hofmann-type coordination polymer, {FeII(PyHbim)2[Pd(CN)4]}·2CH3OH [1·2CH3OH, PyHbim = 2-(4-pyridyl)benzimidazole], has been synthesized, which can undergo a spontaneous guest exchange, transforming to 1·2H2O in a single-crystal-to-single-crystal (SCSC) manner, shifting from orthorhombic Cmmm to monoclinic C2/m involving the displacement of 2D layers. The solvent-induced SCSC transformation process was reversible and verified through powder X-ray diffraction (PXRD) and single-crystal X-ray crystallography analyses. Both 1·2CH3OH and 1·2H2O exhibit complete and abrupt spin crossover (SCO) behaviors in two steps, while their SCO temperature ranges drastically shift by ca.100 K, spanning room temperature, owing to different intermolecular interactions resulting from diverse interlayer packing manners and host-guest interactions. Besides, a structural phase transition is observed in 1·2CH3OH, contributing to the two-step spin transition.

2.
Opt Express ; 31(10): 16795-16811, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157751

RESUMO

Metal coatings can protect the fragile optical fiber sensors and extend their life in harsh environments. However, simultaneous high-temperature strain sensing in a metal-coated optical fiber remains relatively unexplored. In this study, a nickel-coated fiber Bragg grating (FBG) cascaded with an air bubble cavity Fabry-Perot interferometer (FPI) fiber optic sensor was developed for simultaneous high temperature and strain sensing. The sensor was successfully tested at 545 °C for 0-1000 µÉ›, and the characteristic matrix was used to decouple temperature and strain. The metal layer allows easy attachment to metal surfaces that operate at high temperatures, enabling sensor-object integration. As a result, the metal-coated cascaded optical fiber sensor has the potential to be used in real-world structural health monitoring.

3.
Pain Manag Nurs ; 24(2): 157-170, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36400656

RESUMO

OBJECTIVES: To evaluate the effectiveness and safety of traditional Chinese medicine (TCM) mind-body therapies in patients with neuropathic pain. DESIGN: This systematic review was undertaken according to the PRISMA 2020 statement. DATA SOURCES: We searched randomized controlled trials (RCTs) in seven English databases and four Chinese databases up to March 2022. REVIEW/ANALYSIS METHODS: The Cochrane Risk of Bias 2 was used for the quality assessment, and the mean difference with a 95% confidence interval for data pooling. The review was registered in the INPLASY (INPLASY202240016). RESULTS: Twenty-three RCTs were identified, including 1,693 patients with lumbar herniated discs (LHD), cervical spondylotic radiculopathy (CSR), sympathetic cervical spondylosis (SCS), trigeminal neuralgia, and central poststroke pain. Pooled results showed that for LHD, TCM mind-body therapy used alone (MD: -0.57, [-0.77, -0.36], P<0.01, week 8) or combined with physiotherapy (MD: -1.02, [-1.12, -0.91], P<0.01, week 4) showed advantages over physiotherapy alone on pain relief. However, there was no statistical difference on physical function. For CSR, TCM mind-body movement combined with physiotherapy had better effect than physiotherapy alone on pain relief (MD: -1.15, [-1.37, -0.94], P<0.01, week 4). Six trials reported safety. Nausea, dizziness, fatigue, and pain at the acupuncture point were observed. CONCLUSIONS: Low-quality evidence showed that TCM mind-body therapies might reduce pain intensity and improve physical function when used as an adjuvant therapy or monotherapy. There is a need to conduct high-quality trials to confirm the effectiveness and safety of TCM mind-body therapies for neuropathic pain.


Assuntos
Medicina Tradicional Chinesa , Neuralgia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Neuralgia/terapia , Terapias Mente-Corpo , Manejo da Dor
4.
Sensors (Basel) ; 23(10)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37430570

RESUMO

In the process of ocean exploration, highly accurate and sensitive measurements of seawater temperature and pressure significantly impact the study of seawater's physical, chemical, and biological processes. In this paper, three different package structures, V-shape, square-shape, and semicircle-shape, are designed and fabricated, and an optical microfiber coupler combined Sagnac loop (OMCSL) is encapsulated in these structures with polydimethylsiloxane (PDMS). Then, the temperature and pressure response characteristics of the OMCSL, under different package structures, are analyzed by simulation and experiment. The experimental results show that structural change hardly affects temperature sensitivity, and square-shape has the highest pressure sensitivity. In addition, with an input error of 1% F.S., temperature and pressure errors were calculated, which shows that a semicircle-shape structure can increase the angle between lines in the sensitivity matrix method (SMM), and reduce the effect of the input error, thus optimizing the ill-conditioned matrix. Finally, this paper shows that using the machine learning method (MLM) effectively improves demodulation accuracy. In conclusion, this paper proposes to optimize the ill-conditioned matrix problem in SMM demodulation by improving sensitivity with structural optimization, which essentially explains the cause of the large errors for multiparameter cross-sensitivity. In addition, this paper proposes to use the MLM to solve the problem of large errors in the SMM, which provides a new method to solve the problem of the ill-conditioned matrix in SMM demodulation. These have practical implications for engineering an all-optical sensor that can be used for detection in the ocean environment.

5.
Opt Express ; 30(6): 9714-9726, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299391

RESUMO

Based on the polymer encapsulation method, a compact structure and high-sensitivity temperature and pressure dual parametric sensor was developed in this paper by wrapping an optical microfiber coupler (OMC) in polydimethylsiloxane (PDMS). Benefiting from the stable chemical properties and good optical field control ability of PDMS, the sensor showed good stability and repeatability. The dependence of the sensor sensitivity on wavelength, temperature, and pressure was experimentally investigated. The results showed that the temperature and pressure sensitivity could reach -2.283 nm/°C and 3.301 nm/Mpa in the C-band range. To overcome the cross-sensitivity of sensor temperature and pressure, a sensitivity matrix was established to realize dual-parameter simultaneous demodulation. In addition, the pressure repeatability of the sensor was tested. Based on this, the sensitivity matrix was further calibrated to reduce the error and improve the accuracy of demodulation. Finally, we also designed a protective shell for the sensor to meet the requirements of practical marine applications. Compared with other existing types of optical fiber sensors, this sensor has the advantages of simple fabrication, high sensitivity, and environmental adaptability, and has great potential for application in the field of marine environmental monitoring.

6.
Opt Express ; 30(16): 29271-29286, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36299105

RESUMO

To improve the sensing performance of optical fiber magnetic field sensor based on magneto-refractive effect, a D-shaped photonic crystal fiber-surface plasmon resonance (PCF-SPR) sensor based on magneto-refractive effect is proposed and its magnetic field sensing characteristics are investigated. The designed D-shaped PCF has a core-analyte-gold structure. Within the D-shaped PCF, the side polishing surface is coated with the gold film and the special hole is sandwiched between the core and the gold film. To realize the high magnetic field sensitivity for the fiber SPR magnetic field sensor, the special hole is filled with magnetic fluid (MF). In this paper, we analyze the mode transmission characteristics and magnetic field sensing characteristics of this fiber sensor by finite element method. We also obtain a general rule for the optimization of PCF-SPR sensors by analyzing the dispersion curves, the energy of the surface plasmon polariton mode and the core mode on the sensing performance of the designed fiber sensor. The maximum refractive index sensitivity and magnetic field sensitivity of the optimized fiber are 59714.3 nm/RIU and 21750 pm/mT (50-130 Oe), respectively. Compared with optical fiber magnetic field sensors based on magneto-refractive effect reported previously, the magnetic field sensitivity in this paper is nearly two orders of magnitude higher and it can initially achieve nT magnitude magnetic field resolution and testing capability. The proposed fiber sensor has the advantages of simple structure, easy production, high sensitivity, and strong environmental adaptability. It not only improves the sensing performance of optical fiber magnetic field sensors, but also provides an ideal alternative platform for biosensors like microfluidics because of its high refractive index sensitivity and the special structure.

7.
Kidney Blood Press Res ; 47(1): 1-12, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34784607

RESUMO

AIM: The present study aimed to elucidate the potential function of microRNA 1228 (miR-1228) on the high glucose (HG)-damaged human renal proximal tubule cells (HK-2) and the underlying mechanism. METHODS: The datasets GSE47185 and GSE51674 were downloaded from the Gene Expression Omnibus database for mining differently expressed mRNAs and miRNAs, respectively. Bioinformatics online tools were applied to predict the binding sites between miR-1228 and thrombospondin 2 (THBS2), which was confirmed by dual-luciferase assay. Real-time quantitative polymerase chain reaction was used to detect the mRNA level of miR-1228/THBS2. Western blot was used to detect the protein level of THBS2 and the PI3K/AKT signaling pathway-associated markers. HK-2 cells were cultured in HG (30 mM) to mimic hyperglycemia. Cell counting kit 8 and flow cytometry assays were utilized to determine the cell proliferation and apoptosis. RESULTS: The expression of THBS2 was significantly upregulated in diabetic nephropathy (DN) based on bioinformatics tools and identified as a direct target of miR-1228. miR-1228 was downregulated in DN and HG-damaged HK-2 cells. HG notably reduced HK-2 cell proliferation. This negative effect was attenuated by transfecting with an miR-1228 mimic and aggravated by transfecting with an miR-1228 inhibitor. However, under basal condition, there was no significant effect on the HK-2 cell proliferation among blank control, mimic, and inhibitor groups. Overexpression of THBS2 abolished the elevating effect of the miR-1228 mimic on the HG-damaged HK-2 cell proliferation, while restored the inhibitory effects of the miR-1228 mimic on the cell apoptosis. On the contrary, the suppressive effects on the proliferation and the enhancive effects on the apoptosis by silencing miR-1228 in HK-2 cells stimulated with HG can be weakened by recommendation of THBS2 small interference RNAs. Furthermore, we also found that HG significantly enhanced the phosphorylation levels of PI3K and AKT. In terms of overexpression and knockdown experiments, Western blot analysis further revealed that miR-1228 inhibited the activation of the PI3K/AKT signaling pathway in HG-damaged HK-2 cells by regulating THBS2. CONCLUSION: The findings illustrated that miR-1228 improved survivability and inhibited apoptosis in HK-2 cells stimulated with HG partly by restraining the activation of the PI3K/AKT signaling pathway.


Assuntos
Glucose/metabolismo , Túbulos Renais Proximais/metabolismo , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombospondinas/genética , Linhagem Celular , Sobrevivência Celular , Regulação da Expressão Gênica , Humanos , Túbulos Renais Proximais/citologia , MicroRNAs/metabolismo , Transdução de Sinais , Trombospondinas/metabolismo
8.
Sensors (Basel) ; 22(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36501961

RESUMO

The two-stage suspension system (TSSS) is designed for the fiber optic vector hydrophone (FOVH) to isolate the vibration from the mooring rope. The acceleration transmissibility of the TSSS is studied theoretically and experimentally. The results show that the TSSS has a major advantage over the traditional one-stage suspension system (OSSS). Typically, the vibration isolation of the TSSS is demonstrated to be over 25 dB higher than that of the OSSS at 100 Hz. Meanwhile, it is demonstrated that the TSSS has little negative influence on the in-band acceleration response of the FOVH. The TSSS has the prospect of reducing the mechanical noise of the FOVH, which is conducive to suppressing the self-noise and enhancing the ability of weak signal detection.

9.
Sensors (Basel) ; 22(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36365887

RESUMO

Modulation instability (MI) is the main limitation factor of the maximum optical power in long-haul phase-sensitive optical time domain reflectometry (Φ-OTDR), and induces signal fading and serious phase noise. In this paper, a method of coherent seed injection is proposed to suppress the MI-induced phase noise in long-haul Φ-OTDR. The spontaneous MI is suppressed by stimulating induced MI in an optical fiber. The visibility of the signal in Φ-OTDR is enhanced and the phase noise is suppressed significantly. This paper offers an effective method to increase the maximum input power with the MI-induced phase noise suppressed in the long-haul Φ-OTDR system. As a result, the maximum input power and sensing distance can be potentially increased, which is greatly beneficial to the enhancement of the performance of long-haul Φ-OTDR.

10.
Appl Opt ; 60(34): 10643-10648, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200928

RESUMO

To the best of our knowledge, we present what we believe is a novel approach for fading noise reduction in distributed acoustic sensing (DAS). Rayleigh signals in multiple optical modes are collected by a phase-sensitive optical time-domain reflectometry system with a diversity detection scheme. An optimal weighted average algorithm is proposed to synthesize the phase demodulated from the Rayleigh signals, leading to the aggregate phase that presents acoustic signals with optimal fading noise reduction. The validity of the proposed approach is experimentally confirmed by comparison of the fading noise along a 12.8 km sensing fiber in a conventional DAS system and a DAS system that employs the proposed approach.

11.
BMC Public Health ; 21(1): 1180, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154553

RESUMO

BACKGROUND: Digital interventions have potential to efficiently support improved hygiene practices to reduce transmission of COVID-19. OBJECTIVE: To evaluate the evidence for digital interventions to improve hygiene practices within the community. METHODS: We reviewed articles published between 01 January 2000 and 26 May 2019 that presented a controlled trial of a digital intervention to improve hygiene behaviours in the community. We searched MEDLINE, Embase, PsycINFO, Cochrane Controlled Register of Trials (CENTRAL), China National Knowledge Infrastructure and grey literature. Trials in hospitals were excluded, as were trials aiming at prevention of sexually transmitted infections; only target diseases with transmission mechanisms similar to COVID-19 (e.g. respiratory and gastrointestinal infections) were included. Trials had to evaluate a uniquely digital component of an intervention. Study designs were limited to randomised controlled trials, controlled before-and-after trials, and interrupted time series analyses. Outcomes could be either incidence of infections or change in hygiene behaviours. The Risk of Bias 2 tool was used to assess study quality. RESULTS: We found seven studies that met the inclusion criteria. Six studies reported successfully improving self-reported hygiene behaviour or health outcomes, but only one of these six trials, Germ Defence, confirmed improvements using objective measures (reduced consultations and antibiotic prescriptions). Settings included kindergartens, workplaces, and service station restrooms. Modes of delivery were diverse: WeChat, website, text messages, audio messages to mobiles, electronic billboards, and electronic personal care records. Four interventions targeted parents of young children with educational materials. Two targeted the general population; these also used behaviour change techniques or theory to inform the intervention. Only one trial had low risk of bias, Germ Defence; the most common concerns were lack of information about the randomisation, possible bias in reporting of behavioural outcomes, and lack of an analysis plan and possible selective reporting of results. CONCLUSION: There was only one trial that was judged to be at low risk of bias, Germ Defence, which reduced incidence and severity of illness, as confirmed by objective measures. Further evaluation is required to determine the effectiveness of the other interventions reviewed. TRIAL REGISTRATION: PROSPERO CRD42020189919 .


Assuntos
COVID-19 , Pais , Adulto , Criança , China , Comportamentos Relacionados com a Saúde , Educação em Saúde , Humanos , Incidência , SARS-CoV-2
12.
Biotechnol Lett ; 43(2): 393-405, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33165673

RESUMO

OBJECTIVE: Myocardial infarction (MI) is a prevalent cardiovascular puzzle and a mainspring of disease-induced mortality. We performed this investigation to detect the role of putative important miRNAs or genes in MI. RESULTS: CCL20 may be a potential therapeutic target, which was directly targeted and negatively regulated by miR-19a. CCL20 expression was significantly increased in MI tissue samples, but miR-19a was expressed at lower levels in MI. H/R treatment inhibited cell viability and induced an increase of apoptotic rate compared with Sham group. However, miR-19a mimic relieved the H/R-stimulated injury to cardiomyocytes. Protective effect of miR-19a against H/R in cardiomyocytes was reversed by CCL20 enhancement, and MAPK pathway was inactivated during this progression. CONCLUSIONS: miR-19a eliminates the H/R-induced injury in cardiomyocytes through directly targeting CCL20 and attenuating the activity of MAPK signaling pathway. These observations highlighted the therapeutic roles of miR-19a and CCL20 for MI treatment.


Assuntos
Quimiocina CCL20/genética , MicroRNAs/genética , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/genética , Apoptose/genética , Hipóxia Celular/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica/genética , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Terapia de Alvo Molecular , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/terapia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Oxigênio/metabolismo , Transdução de Sinais/genética
13.
J Med Internet Res ; 23(2): e22197, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33566791

RESUMO

BACKGROUND: To control the COVID-19 pandemic, people should adopt protective behaviors at home (self-isolation, social distancing, putting shopping and packages aside, wearing face coverings, cleaning and disinfecting, and handwashing). There is currently limited support to help individuals conduct these behaviors. OBJECTIVE: This study aims to report current household infection control behaviors in the United Kingdom and examine how they might be improved. METHODS: This was a pragmatic cross-sectional observational study of anonymous participant data from Germ Defence between May 6-24, 2020. Germ Defence is an open-access fully automated website providing behavioral advice for infection control within households. A total of 28,285 users sought advice from four website pathways based on household status (advice to protect themselves generally, to protect others if the user was showing symptoms, to protect themselves if household members were showing symptoms, and to protect a household member who is at high risk). Users reported current infection control behaviors within the home and intentions to change these behaviors. RESULTS: Current behaviors varied across all infection control measures but were between sometimes (face covering: mean 1.61, SD 1.19; social distancing: mean 2.40, SD 1.22; isolating: mean 2.78, SD 1.29; putting packages and shopping aside: mean 2.75, SD 1.55) and quite often (cleaning and disinfecting: mean 3.17, SD 1.18), except for handwashing (very often: mean 4.00, SD 1.03). Behaviors were similar regardless of the website pathway used. After using Germ Defence, users recorded intentions to improve infection control behavior across all website pathways and for all behaviors (overall average infection control score mean difference 0.30, 95% CI 0.29-0.31). CONCLUSIONS: Self-reported infection control behaviors other than handwashing are lower than is optimal for infection prevention, although handwashing is much higher. Advice using behavior change techniques in Germ Defence led to intentions to improve these behaviors. Promoting Germ Defence within national and local public health and primary care guidance could reduce COVID-19 transmission.


Assuntos
COVID-19/prevenção & controle , COVID-19/transmissão , Controle de Infecções/métodos , Intervenção Baseada em Internet , COVID-19/epidemiologia , Estudos Transversais , Transmissão de Doença Infecciosa/prevenção & controle , Características da Família , Comportamentos Relacionados com a Saúde , Humanos , SARS-CoV-2 , Inquéritos e Questionários , Reino Unido/epidemiologia
14.
Appl Opt ; 59(21): 6333-6339, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32749297

RESUMO

Phase-sensitive optical time-domain reflectometry (Φ-OTDR) implements distributed vibration measurements by demodulation of vibration-induced phase of Rayleigh backscattered light waves (RBLs), and suffers from measurement instability. The weak intensities of RBLs and the resulting low signal-to-noise ratios (SNRs) of intensity measurements are the dominating factors that cause the instability of vibration measurements. In this paper, dependence of the measurement stability of heterodyne Φ-OTDR on the SNR of the intensity measurement is investigated analytically and experimentally. An analytical solution of the probability density function of the demodulated phase as a function of SNR is obtained through rigorous derivation, and the dependence of the measurement stability on the SNR is investigated by analyzing the probability density function distribution of the demodulated phase. Both the theoretical predictions and experimental results reveal the impact of SNR on the measurement stability of heterodyne Φ-OTDR. This study fulfills the Φ-OTDR theory and would lead to an effective approach to stabilizing vibration quantization.

15.
J Cell Physiol ; 234(7): 10554-10565, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30623413

RESUMO

TCEA3 is a member of the transcription elongation factor family that not only promotes transcription but may also participate in other cytoplasmic processes. However, its mechanisms of action remain unclear. Our previous study indicated that TCEA3 may affect muscle differentiation. In this study, we investigated the expression and localization of TCEA3 in C2C12 cells and examined the role of TCEA3 in differentiation, its interaction with other cell proteins, and mechanisms of action. We found that the expression of TCEA3 increased gradually with an increase in the number of differentiation days and that it is mainly expressed in the cytoplasm of C2C12 cells, of which it promotes differentiation. Coimmunoprecipitation experiments and western blot analysis revealed that TCEA3 interacts with Annexin A1 (ANXA1), which is located in the cytoplasm and also promotes cell differentiation. Collectively, our results indicate that TCEA3 promotes cell differentiation by interacting with ANXA1 and affecting transforming growth factor-ß signaling pathways.


Assuntos
Anexina A1/genética , Transcrição Gênica , Fatores de Elongação da Transcrição/genética , Fator de Crescimento Transformador beta/genética , Animais , Diferenciação Celular/genética , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento/genética , Camundongos , Transdução de Sinais/genética
16.
Metab Brain Dis ; 34(5): 1355-1363, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31134481

RESUMO

Accumulation of extracellular amyloid-ß (Aß) in hippocampal subregions is a hallmark of Alzheimer's disease (AD), which promotes neuronal apoptosis, potentiates cognitive decline and play a causative role in AD pathogenesis. However, whether this process is controlled by distinct miRNAs at the posttranscriptional level remain fascinating but poorly understood. Using post mortem hippocampal samples from human AD patients and 3xTg-AD mouse, we demonstrate that miR-342-3p expression was significantly induced during the AD development. With the aid of intrahippocampal injection of miR-342-3p antagomir, we further show that in vivo miR-342-3p inhibition synergistically improved cognitive deficits in 3xTg-AD mice. The hippocampal Aß-plaque burden in 3xTg-AD mice, as revealed by immunohistochemical analysis with 4G8 antibody, was attenuated also. Mechanistically, the upregulation of neuronal miR-342-3p is linked to an increase in the activation of the stress kinase c-Jun N-terminal kinase with the subsequent death of the neurons in Aß-challenged HT22 hippocampal neuronal cells. These findings support the model that derangement of hippocampus signal transduction and subsequent neuronal apoptosis in AD arises as a consequence of increased Aß burden and chronic activation of the JNK MAPK cascade in a miR-342-3p-dependent manner. Overall, we described for the first time the regulatory activity of miR-342-3p on relevant Aß metabolism pathways in Alzheimer's disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antagomirs/uso terapêutico , Hipocampo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Placa Amiloide/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Antagomirs/administração & dosagem , Linhagem Celular , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Placa Amiloide/genética , Placa Amiloide/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
17.
Opt Lett ; 43(15): 3642-3645, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30067644

RESUMO

A method is proposed to suppress spontaneous modulation instability (MI) and phase noise with a coherent seed in the interferometric fiber sensing systems. By generating coherent seeds with phase modulation, induced MI is excited in an optical fiber. The preferential gain of the coherent seeds compared to the amplified spontaneous emission noise suppresses spontaneous MI. As a result, the induced MI dominates in the optical fiber. The coherence of the output light is enhanced, and the phase noise is suppressed significantly. The maximum input power can be increased significantly, and the sensing range can be extended.

18.
Int J Clin Pharmacol Ther ; 56(4): 197-204, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29424335

RESUMO

A simple and fast ultra-performance liquid chromatography-tandem mass spectrometry method was developed and validated to determine entecavir in human plasma with the stable isotopically labeled internal standard entecavir-13C215N. Samples (100 µL each) were pretreated by protein precipitation with methanol, and then separated on an ACQUITY UPLC BEH C18 analytical column (2.1 × 50 mm, 1.7 µm) with a simple isocratic elution. The detection was operated by a positive ionization electrospray mass spectrometry in multiple reaction monitoring mode. The method had a short chromatographic run time of 2 minutes, and obtained sharp peaks of entecavir and the internal standard. Good linearity was found within 0.1 - 20 ng/mL. The intra- and inter-day precision and accuracy met the acceptance criteria, and no matrix effect was observed. This method was successfully applied in a bioequivalence study of two kinds of entecavir tablets in healthy Chinese volunteers. And the results showed that no significant differences were found between the test and reference preparations in pharmacokinetic parameters (p > 0.05) by ANOVA. The 90% confidence intervals for the geometric mean ratios (test/reference) of Cmax, AUC0-tlast, and AUC0-∞ fell within the bioequivalence acceptance criteria (80 - 125%). No significant difference was found in tmax between the two preparations. The two one-sided t-tests showed that these two products were bioequivalent.
.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Guanina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Guanina/sangue , Guanina/farmacocinética , Humanos , Equivalência Terapêutica
19.
Biochem Biophys Res Commun ; 485(2): 535-541, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28131828

RESUMO

EP3 is a receptor for prostaglandin E2 (PGE2), and although its effect on bladder excitability has attracted considerable attention, the underlying mechanism remains unclear. To investigate whether the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in the interstitial cells of Cajal (ICCs) of the bladder are involved in the effect of EP3 activation on bladder excitability, wild-type mice, HCN1 knockout (HCN1-/-) mice and rats were used in our study. Double immunofluorescence staining and immunoprecipitation assays demonstrated the interaction between EP3 and the HCN channels. Sulprostone is a selective agonist of EP3. The current density of HCN channels was enhanced by sulprostone or PGE2 using whole-cell patch clamping. Western blot analyses showed that the expression levels of HCN1 and HCN4 were higher in bladders that had undergone intravesical instillation with sulprostone than in bladders treated with normal saline (NS). Both PGE2 and sulprostone increased the calcium concentration of the ICCs, and their effects were inhibited by ZD7288 (antagonist of HCN channels) treatment. In bladder detrusor strip testing, both PGE2 and sulprostone enhanced the amplitude of the bladder detrusor in HCN1-/- mice; however, these effects were less than those in the wild-type mice. Furthermore, the effects of PGE2 and sulprostone were inhibited by ZD7288. Taken together, our results indicate that EP3 is expressed in bladder ICCs and facilitates bladder excitability via HCN channels. This study provides more comprehensive insights into the mechanism between inflammation and bladder excitability and highlights methods that can resolve bladder hyperactivity.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Células Intersticiais de Cajal/metabolismo , Receptores de Prostaglandina E Subtipo EP3/metabolismo , Bexiga Urinária/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Células Cultivadas , Dinoprostona/análogos & derivados , Dinoprostona/farmacologia , Feminino , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/antagonistas & inibidores , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Células Intersticiais de Cajal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Contração Muscular/efeitos dos fármacos , Ligação Proteica , Pirimidinas/farmacologia , Ratos Sprague-Dawley , Receptores de Prostaglandina E Subtipo EP3/agonistas , Bexiga Urinária/citologia , Bexiga Urinária/efeitos dos fármacos
20.
Appl Opt ; 56(35): 9793-9803, 2017 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29240127

RESUMO

The dynamic characteristics of the cavity mirror support structure strongly influence the quality of the output beam. However, the contradiction between excellent dynamic performance and light weight make the design process challenging. To cope with the problems encountered in the original design of a chemical oxygen iodine laser system, this paper presents a two-dimensional adjustable support structure based on spherical constraints with large specific stiffness in the initial design phase. Subsequently, a two-level optimization strategy containing a macro design and a detailed design is adopted to optimize the initial structure. At the macro design stage, a two-step topology optimization procedure is introduced, in which the scale of the optimization model is dramatically reduced using the independent continuous mapping algorithm to improve the calculation speed in the first step, and the gray elements are eliminated using the bi-directional evolutionary structural optimization method to clearly obtain the optimal topology in the second step. This method is verified to overcome the defect of low efficiency, while still eliminating gray elements. At the detailed design stage, an adaptive surrogate model and the multi-objective design optimization method are employed to seek the best compromise between the lower weight and higher dynamic performance. The results from the application to the example of the cavity mirror support structure show that the mass is reduced by 41.8%, and the dynamic performance requirement is fulfilled.

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