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1.
Heliyon ; 10(11): e31465, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38882363

RESUMO

Chemokines regulate the trophoblast dysfunction involved in the occurrence and development of pathological pregnancy, including missed abortions. In particular, CXC chemokine receptor type 5 mediates cell proliferation, migration, and inflammation; nonetheless, its role in missed abortions remains unclear. This study aimed to examine the expression of CXC chemokine receptor type 5 in missed abortions and to investigate the effects of CXC chemokine receptor type 5 on the biological behaviour of trophoblasts, as well as the underlying mechanisms. Our results indicated that CXC chemokine receptor type 5 was upregulated in the villi of women who experienced unexplained missed abortions, as compared with those who had normal pregnancies. CXC chemokine receptor type 5 inhibited the proliferation and migration of human first-trimester trophoblast/simian virus cells but promoted cell apoptosis. With respect to its mechanisms, CXC chemokine receptor type 5 activated the extracellular signal-regulated protein kinase 1/2 signalling pathway and upregulated the secretion of interleukin-6; however, it had no effect on the secretion of tumour necrosis factor-α. In conclusion, our findings suggest that CXC chemokine receptor type 5 induces trophoblast dysfunction and participates in the processes of unexplained missed abortions, wherein p-ERK and interleukin-6 may be involved.

2.
Opt Express ; 31(23): 38114-38131, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017926

RESUMO

A differential FMCW LiDAR for high-precision distance measurements of remote non-stationary targets is proposed and demonstrated experimentally. The required positive and negative symmetrically oppositely chirped laser beams are generated synchronously through a fixed-frequency laser by employing externally unified broadband optical phase modulation and symmetrical dual-sideband optical filtering. After coaxial transmission and reception, orthogonally polarized optical beat signals containing target distance and vector velocity data are de-chirped separately by optical in-phase and quadrature demodulations and then synchronously received by four-channel photoelectric balance detectors. After differential processing of the received beat signals and a fast Fourier transform, it is possible to implement real-time simultaneous range and vector velocity measurements. The inherent symmetrically oppositely chirped optical frequency make it possible to measure the target distance immune to the internal random phase noise introduced by the spectral linewidth of the frequency-swept laser and the external random phase noise introduced by atmospheric turbulence, speckle, and vibration. Meanwhile, the measurement of the target velocity is immune to the nonlinearity of the frequency-swept laser. These results encourage an approach to overcome the barriers of coherence length, nonlinearity, and external noise, and implement simultaneous real-time ranging and velocimetry of long-range, rapid-moving targets.

3.
Front Physiol ; 14: 1183610, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082242

RESUMO

Introduction: Carboxylesterases (CXEs) and glutathione S-transferases (GSTs) can terminate olfactory signals during chemosensation by rapid degradation of odorants in the vicinity of receptors. The tea grey geometrid, Ectropis grisescens (Lepidoptera, Geometridae), one of the most devastating insect herbivores of tea plants in China, relies heavily on plant volatiles to locate the host plants as well as the oviposition sites. However, CXEs and GSTs involved in signal termination and odorant clearance in E. grisescens remains unknown. Methods: In this study, identification and spatial expression profiles of CXEs and GSTs in this major tea pest were investigated by transcriptomics and qRT-PCR, respectively. Results: As a result, we identified 28 CXEs and 16 GSTs from female and male antennal transcriptomes. Phylogenetic analyses clustered these candidates into several clades, among which antennal CXEs, mitochondrial and cytosolic CXEs, and delta group GSTs contained genes commonly associated with odorants degradation. Spatial expression profiles showed that most CXEs (26) were expressed in antennae. In comparison, putative GSTs exhibited a diverse expression pattern across different tissues, with one GST expressed specifically in the male antennae. Disscussion: These combined results suggest that 12 CXEs (EgriCXE1, 2, 4, 6, 8, 18, 20-22, 24, 26, and 29) and 5 GSTs (EgriGST1 and EgriGST delta group) provide a major source of candidate genes for odorants degradation in E. grisescens.

4.
Appl Opt ; 62(2): 298-313, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36630228

RESUMO

This paper systematically presents the design and performance of an extremely sensitive 1.55-µm free-space monostatic laser Doppler vibrometer (LDV) using optical homodyne detection for real-time acquisition and enhancement of the remote acoustic signals. The phase shifts produced by laser light scattered off a remote target carries the extremely tiny vibration displacement information of the target' surface motivated by the acoustic source around and is demodulated using the optical in-phase/quadrature demodulator. The real-time acquisitions of the remote acoustic signals, including the sinusoidal signal and the speech signal at the target distance of 100 m, is performed between two buildings. The real-time speech enhancement of remote speech signals is also carried out by the different algorithms based on the short-time spectral magnitude, and the comprehensible speech signals can be reconstructed. The results demonstrate that the designed free-space monostatic homodyne LDV has a low system background noise and can offer high precision for the uncooperative targets in the real-time acquisition of the remote acoustic signal.

5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 39(9): 969-973, 2022 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-36082567

RESUMO

OBJECTIVE: To analyze the clinical and genetic characteristics of a Chinese pedigree affected with developmental and epileptic encephalopathy 9. METHODS: N048: epilepsy full version gene detection panel-V2 and genome wide copy number variation analysis were carried out on the genomic DNA extracted from the peripheral blood samples. Amniotic fluid was also sampled for single nucleoticle polymorphism array (SNP-array) analysis. RESULTS: Both the mother and her daughter were found to have loss of heterozygosity at Xq21.31q22.1, with which exons of protocadherin 19 (PCDH19) gene was deleted. SNP-array showed the fetus to be a female and had arr[hg19]Xq21.31q22.1 (89 558 626-99 701 006)x1. The mother, daughter and fetus of this family all had developmental and epileptic encephalopathy 9. CONCLUSION: Variant of the PCDH19 gene probably underlay the Developmental and epileptic encephalopathy 9 in this pedigree.


Assuntos
Epilepsia Generalizada , Epilepsia , Caderinas/genética , China , Variações do Número de Cópias de DNA , Epilepsia/diagnóstico , Epilepsia/genética , Feminino , Humanos , Mutação , Linhagem , Protocaderinas
6.
Cancer Manag Res ; 14: 515-524, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173485

RESUMO

BACKGROUND: Patients with locally advanced (stage III) non-small cell lung cancer (NSCLC) demonstrate broad anatomic heterogeneity with modest survival benefits. Immune checkpoint inhibitors (ICIs) have shown survival benefit in metastatic NSCLC. We conducted this study to evaluate the efficacy and safety of neoadjuvant nivolumab in combination with chemotherapy in the treatment of this population. METHODS: We retrospectively evaluated patients with locally advanced NSCLC receiving neoadjuvant nivolumab and chemotherapy (paclitaxel with carboplatin) followed by surgery at our institution from January 2019 to January 2020. RESULTS: A total of 46 eligible patients, 26 males, and 20 females were diagnosed with NSCLC in a stage IIIA (30 cases) and IIIB (16 cases) to receive neoadjuvant treatment. The treatment was well tolerated with just 7 (15.2%) typical immune-related adverse events (hyperthyroidism, hyperglycemia, and rash) recorded. A total of 45 patients underwent surgical resection, and 43 (95.6%) of them achieved a R0 resection. No major surgical complications were observed. There was a complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) in 2 (4.3%), 26 (56.5%), 17 (37.0%), 6 (26.1%), and 1 (2.2%) patients. Eight patients resulted in a major pathological response (MPR) (17.4%) and 24 patients had a pathological complete response (pCR) (52.2%). At the time of data cutoff (June 1, 2021), the median follow-up period was 15.5 months (IQR 3.9-29) and 27 (60%) of 45 patients who had tumor resection were progression free. At 24 months, progression-free survival was 45.8% and overall survival was 79.9%. CONCLUSION: Nivolumab plus paclitaxel and carboplatin could be a potential neoadjuvant regimen for patients with locally advanced NSCLC, rendering a potentially lethal disease to one that is curable.

7.
Appl Opt ; 59(32): 10026-10034, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33175775

RESUMO

This paper systematically investigates the influences of polarization states on laser-induced domain nucleation in z-cut LiNbO3 crystals. The real-time 2D and 3D phase distributions at the focus during laser-induced domain nucleation were reconstructed by digital holography. The different LiNbO3 samples, including undoped congruent LiNbO3, Mg-doped congruent LiNbO3, Hf-doped congruent LiNbO3, and stoichiometric LiNbO3, were tested. The systematical comparisons of phase mapping and nucleation fields with different polarization states, including linear polarization, circular polarization, and elliptical polarization, have been carried out. The polarization states proved to be a key influence factor for the laser-induced domain nucleation. It was demonstrated that the generated bulk photovoltaic field along the -z direction was an important mechanism for laser-induced preferential domain nucleation. This work is of great significance for the future development of ferroelectric domain engineering of LiNbO3 crystals.

8.
Appl Opt ; 59(2): 315-323, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32225309

RESUMO

Because the physical properties of lithium niobate (LiNbO3) strongly depend on composition, accurate and convenient methods for the determination of the composition are of great significance. Although several optical methods, including the measurement of UV absorption edge, the birefringence, and the second-harmonic generation, have been proved to be convenient for an accurate and fast standard determination of composition in LiNbO3 single crystals, their research and commercial applications are limited by the doping component and the complex nonlinear relationships. Based on preliminary work, a novel optical method to determine the composition of LiNbO3 crystals by digital holography is proposed. This method is based on the static internal field, which is obtained by means of the three-dimensional (3D) static measurement of the phase difference between antiparallel poling states without applying external voltage by digital holography. In order to investigate the influences of composition and doping on the static internal field in LiNbO3 crystals, the measured static internal fields from various LiNbO3 samples with different stoichiometry, doping type, and doping level are summarized and compared. Excluding the influence of dopant, the composition has been proved to be a unique key influencing factor on the static internal field in LiNbO3 crystals. A systematic measurement based on the static internal field from various sources with compositions ranging from 48.5 to 49.9 mol.% (Li/[Li+Nb] ratio) has been carried out. The approximate linear fit between the static internal field and composition can provide an easy, reliable, and sensitive determination of the composition in undoped and doped LiNbO3 samples.

9.
J Biomed Opt ; 21(12): 120502, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27992630

RESUMO

High resolution is important for sensitive detection of subtle distortions of retinal morphology at an early stage of eye diseases. We demonstrate virtually structured detection (VSD) as a feasible method to achieve in vivo super-resolution ophthalmoscopy. A line-scanning strategy was employed to achieve a super-resolution imaging speed up to 127 ?? frames / s with a frame size of 512 × 512 ?? pixels . The proof-of-concept experiment was performed on anesthetized frogs. VSD-based super-resolution images reveal individual photoreceptors and nerve fiber bundles unambiguously. Both image contrast and signal-to-noise ratio are significantly improved due to the VSD implementation.


Assuntos
Oftalmoscopia/métodos , Retina/diagnóstico por imagem , Animais , Anuros , Desenho de Equipamento , Humanos , Microscopia/instrumentação , Microscopia/métodos , Retina/citologia , Razão Sinal-Ruído
10.
Opt Lett ; 40(8): 1683-6, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25872047

RESUMO

Virtually structured detection (VSD) has been demonstrated to break the diffraction limit in scanning laser microscopy (SLM). VSD provides an easy, low-cost, and phase-artifact-free strategy to achieve super-resolution imaging. However, practical application of this method is challenging due to a limited image acquisition speed. We report here the combination of VSD and line-scanning microscopy (LSM) to improve the image acquisition speed. A motorized dove prism was used to achieve automatic control of four-angle (i.e., 0°, 45°, 90°, and 135°) scanning, thus ensuring isotropic resolution improvement. Both an optical resolution target and a living frog eyecup were used to verify resolution enhancement.


Assuntos
Microscopia Confocal/métodos , Animais , Anuros , Processamento de Imagem Assistida por Computador , Retina/citologia , Razão Sinal-Ruído , Fatores de Tempo
11.
Quant Imaging Med Surg ; 5(1): 1-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25694947

RESUMO

BACKGROUND: Angular spectroscopy of light scattering can be used for quantitative analysis of cellular and subcellular properties, and thus promises a noninvasive methodology for in vivo assessment cellular integrity to complement in vitro histological examination. Spatial information is essential for accurate identification of localized abnormalities. However, conventional angular spectroscopy systems only provide single-channel measurement, which suffers from poor spatial resolution or requires time-consuming scanning over extended area. The purpose of this study was to develop a multi-channel angular spectroscopy for light field imaging in biological tissues. MATERIALS AND METHODS: A microlens array (MLA) (8×8) based light field imager for 64-channel angular spectroscopy was developed. A pair of crossed polarizers was employed for polarization-sensitive recording to enable quantitative measurement at high signal specificity and sensitivity. The polarization-sensitive light field imager enables rapid measurement of multiple sampling volumes simultaneously at 18 µm spatial-resolution and 3° angular-resolution. Comparative light field imaging and electrophysiological examination of freshly isolated and physiologically deteriorated lobster leg nerves have been conducted. RESULTS: Two-dimensional (2D) polarization-sensitive scattering patterns of the fresh nerves were highly elliptical, while they gradually lost the ellipticity and became rotationally symmetric (i.e., circular) as the nerves physiologically deteriorated due to repeated electrical stimulations. Characterized parameters, i.e., the ellipticity and the scattering intensity, rendered spatially various characteristics such as different values and deteriorating rates. CONCLUSIONS: The polarization-sensitive light field imager is able to provide multi-channel angular spectroscopy of light scattering with both spatial and angular resolutions. The light scattering properties of nerves are highly dependent on the orientation of nerves and their physiological status. Further development of polarization-sensitive multi-channel angular spectroscopy may promise a methodology for rapid and reliable identification of localized abnormalities in biological tissues.

12.
Crit Rev Biomed Eng ; 43(4): 297-322, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27480461

RESUMO

Light microscopy plays a key role in biological studies and medical diagnosis. The spatial resolution of conventional optical microscopes is limited to approximately half the wavelength of the illumination light as a result of the diffraction limit. Several approaches-including confocal microscopy, stimulated emission depletion microscopy, stochastic optical reconstruction microscopy, photoactivated localization microscopy, and structured illumination microscopy-have been established to achieve super-resolution imaging. However, none of these methods is suitable for the super-resolution ophthalmoscopy of retinal structures because of laser safety issues and inevitable eye movements. We recently experimentally validated virtually structured detection (VSD) as an alternative strategy to extend the diffraction limit. Without the complexity of structured illumination, VSD provides an easy, low-cost, and phase artifact-free strategy to achieve super-resolution in scanning laser microscopy. In this article we summarize the basic principles of the VSD method, review our demonstrated single-point and line-scan super-resolution systems, and discuss both technical challenges and the potential of VSD-based instrumentation for super-resolution ophthalmoscopy of the retina.


Assuntos
Microscopia Confocal/métodos , Retina/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Realidade Virtual , Análise de Fourier , Microscopia/métodos , Microscopia Eletrônica de Varredura , Retina/anatomia & histologia , Doenças Retinianas/patologia
13.
Opt Lett ; 39(24): 6923-6, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25503031

RESUMO

Dynamic near infrared microscopy has revealed transient retinal phototropism (TRP) correlated with oblique light stimulation. Here, by developing a hybrid confocal microscopy and optical coherence tomography (OCT), we tested sub-cellular source of the TRP in living frog retina. Dynamic confocal microscopy and OCT consistently revealed photoreceptor outer segments as the anatomic source of the TRP. Further investigation of the TRP can provide insights in better understanding of Stiles-Crawford effect (SCE) on rod and cone systems, and may also promise an intrinsic biomarker for early detection of eye diseases that can produce photoreceptor dysfunction.


Assuntos
Luz , Segmento Externo das Células Fotorreceptoras da Retina/efeitos da radiação , Tomografia de Coerência Óptica , Animais , Anuros , Estudos de Viabilidade
14.
Appl Opt ; 53(14): 3010-8, 2014 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-24922020

RESUMO

In the paper, the principle and structure of a pupil-matching optical differential receiver consisting of double 4f confocal lens groups is introduced to overcome atmosphere turbulences in space-to-ground laser communication. Using the scalar diffraction theory, a systematic analysis of 4f lens groups is formulated mathematically. Based on Seidel aberration, lens aberrations produced by the inherent unideal lens and mutual alignment errors of double 4f lens groups primarily caused by relative axial displacement of the foci and vertical position change of the optical axes are studied mathematically and detailed. Under the effects of varying aberrations on the double 4f lens groups, we evaluate the performance of this receiving system by the model of power penalty for a given 10(-9) bit error ratio. Simulated results of the relationship between power penalty and the different root-mean-square errors are concluded in order to put forward the requirement of machining precision of individual components. That will be helpful in optimizing the design of these groups in the optical receiver.

15.
Appl Opt ; 53(9): 1846-55, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24663462

RESUMO

A two-dimensional (2D) Fourier transform algorithm for the image reconstruction of synthetic-aperture imaging ladar (SAIL) collected data is suggested. This algorithm consists of quadratic phase compensation in azimuth direction and 2D fast Fourier transform. Based on this algorithm and the parallel 2D Fourier transform capability of spherical lens, an optical principle scheme that processes the SAIL data is proposed. The basic principle, design equations, and necessary analysis are presented. To verify this principle scheme, an experimental optical SAIL processor setup is constructed. The imaging results of SAIL data obtained by our SAIL demonstrator are presented. The optical processor is compact, lightweight, and consumes low power. This optical processor can also provide inherent parallel and speed-of-light computing capability, and thus has potential applications in on-board and satellite-borne SAIL systems.

16.
Opt Lett ; 38(15): 2663-5, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23903105

RESUMO

An improved type of Dammann grating (DG) that could generate an equal-intensity spot array which has only three phases is proposed. Numerical solutions of 1×4 and 1×5 such DGs are given. A 4×4 two-phase DG manufactured by very-large-scale integration (VLSI) techniques is presented. A phase-shift-interferometry-based technique that measures the intensity and sub-beam phases of beam splitting gratings is proposed. The performance measurements of the manufactured 4×4 two-phase DG using the proposed technique is carried out.

17.
Ecotoxicol Environ Saf ; 74(6): 1659-63, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21680020

RESUMO

A residue analytical method for the determination of bromoxynil in soil and maize was developed using high performance liquid chromatography with diode-array detector (HPLC-DAD) and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The residual level and dissipation rate of bromoxynil in the soil and maize crops were determined using the established method. The mean half-life of bromoxynil in soil was 4.12 days with a dissipation rate of 91.25% over 21 days. The mean half-life in maize seedling was 1.14 days with a dissipation rate of 97.79% over 7 days. The final residues of bromoxynil were undetectable in maize grain, maize stem and soil at the harvest time, suggesting that residual levels of bromoxynil in maize plants are safe to humans and animals as well as to the environment.


Assuntos
Herbicidas/análise , Nitrilas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Zea mays/química , Animais , Cromatografia Líquida de Alta Pressão , Meia-Vida , Herbicidas/química , Nitrilas/química , Resíduos de Praguicidas/química , Caules de Planta/química , Solo/química , Microbiologia do Solo , Poluentes do Solo/química , Espectrometria de Massas em Tandem
18.
Bull Environ Contam Toxicol ; 87(1): 50-3, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21533830

RESUMO

A method for residue analysis of fenoxaprop-P-ethyl and its metabolite (i.e., fenoxaprop-P) was developed using high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). This method was then used to evaluate the residual level and dissipation rate of fenoxaprop-P-ethyl and fenoxaprop-P in the soil and wheat. The half-life of fenoxaprop-P-ethyl in wheat plants and soil was 1.50, 2.36 days in Beijing, and 2.28, 1.79 days in Hubei, respectively. The ultimate residues of the two compounds were undetected in soil, wheat grain and stem at the harvest time, suggesting that fenoxaprop-P-ethyl could be safely used in wheat crops with an appropriate dosage and application.


Assuntos
Herbicidas/metabolismo , Oxazóis/metabolismo , Resíduos de Praguicidas/análise , Propionatos/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Triticum/química , China , Cromatografia Líquida de Alta Pressão , Grão Comestível/química , Meia-Vida , Herbicidas/análise , Oxazóis/análise , Resíduos de Praguicidas/metabolismo , Caules de Planta/química , Propionatos/análise , Poluentes do Solo/análise , Espectrometria de Massas em Tandem
19.
Appl Opt ; 50(11): 1554-9, 2011 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21478928

RESUMO

Optimal recording wavelength for maximum diffraction efficiency of thermal fixing in LiNbO(3):Fe crystal is investigated. Holographic gratings are recorded using three typical recording wavelengths including 488, 514, and 633 nm. Optimal switching from recording to thermal fixing is taken into consideration. The fixed holograms are developed by an original recording setup. Diffraction efficiencies of recording and thermal fixing are measured by a two-wave coupling technique. The theoretical and experimental results are analyzed and compared. With a blue beam, the nonvolatile hologram with maximum fixing efficiency is achieved. This work can obtain high persistent diffraction of the nonvolatile holographic storage in LiNbO(3):Fe crystals.

20.
J Opt Soc Am A Opt Image Sci Vis ; 26(1): 135-41, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19109609

RESUMO

The multilayer coupled wave theory is extended to systematically investigate the diffraction properties of multilayer volume holographic gratings (MVHGs) under ultrashort laser pulse readout. Solutions for the diffracted and transmitted intensities, diffraction efficiency, and the grating bandwidth are obtained in transmission MVHGs. It is shown that the diffraction characteristics depend not only on the input pulse duration but also on the number and thickness of grating layers and the gaps between holographic layers. This analysis can be implemented as a useful tool to aid with the design of multilayer volume grating-based devices employed in optical communications, pulse shaping, and processing.

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