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1.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37958940

RESUMO

As members of pathogen-associated molecular patterns, bacterial heat shock proteins (HSPs) are widely recognized for their role in initiating innate immune responses. This study aimed to examine the impact of DnaJ, a homolog of HSP40 derived from Pseudomonas aeruginosa (P. aeruginosa), on the regulation of IL-1ß expression in macrophages. We demonstrated that DnaJ modulates macrophages to secrete IL-1ß by activating NF-κB and MAPK signaling pathways. Specifically, ERK was identified as a positive mediator for IL-1ß expression, while p38 acted as a negative mediator. These results suggest that the reciprocal actions of these two crucial MAPKs play a vital role in controlling IL-1ß expression. Additionally, the reciprocal actions of MAPKs were found to regulate the activation of inflammasome-related molecules, including vimentin, NLRP3, caspase-1, and GSDMD. Furthermore, our investigation explored the involvement of CD91/CD40 in ERK signaling-mediated IL-1ß production from DnaJ-treated macrophages. These findings emphasize the importance of understanding the signaling mechanisms underlying IL-1ß induction and suggest the potential utility of DnaJ as an adjuvant for stimulating inflammasome activation.


Assuntos
Inflamassomos , Pseudomonas aeruginosa , Inflamassomos/metabolismo , Pseudomonas aeruginosa/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais , Macrófagos/metabolismo , NF-kappa B/metabolismo , Interleucina-1beta/metabolismo
2.
Microb Pathog ; 165: 105465, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35247500

RESUMO

Toll-like receptor 7 (TLR7) signaling plays pivotal roles in innate immunity by sensing viral single-stranded RNA thereby triggering inflammatory signaling cascades and eliciting protective antiviral responses. In this study, we found that TLR7 expression is highly induced in response to Pseudomonas aeruginosa (P. aeruginosa) infection in a dose- and time-dependent manner. P. aeruginosa-derived DnaJ, a homolog of HSP40, was identified as a related inducing agent for TLR7 expression, and expression of DnaJ was stimulated when host cells were infected with P. aeruginosa. Interestingly, DnaJ was not involved in mediating an increase in the expression levels of TLR3 and TLR8, other well-known antiviral receptors. The induction of TLR7 in response to DnaJ was mediated by the activation of the AKT (Thr308 and Ser473)/NF-κB and p38/JNK MAPKs signaling pathways, consequently transmitting related signals for the expression of interferons (IFNs). Of note, these antiviral responses were regulated, at least in part, by TLR4, which senses the presence of DnaJ and then promotes downstream activation of the AKT (Ser473)/NF-κB and JNK signaling cascades. Taken together, these results suggest that P. aeruginosa-derived DnaJ is sufficient to promote an increase in TLR7 expression in the TLR4-engaged AKT/NF-κB and JNK signaling pathways, thereby promoting an increased antiviral response through the elevated expression of IFNs.


Assuntos
NF-kappa B , Receptor 7 Toll-Like , Antivirais , Interferons/metabolismo , Sistema de Sinalização das MAP Quinases , Macrófagos/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pseudomonas aeruginosa/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo
3.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925033

RESUMO

Microbe-derived factors trigger innate immune responses through the production of inflammatory mediators, including pentraxin 3 (PTX3). PTX3 is a soluble pattern recognition molecule that stimulates the clearance of clinically important bacterial pathogens such as Pseudomonas aeruginosa. However, the P. aeruginosa factors responsible for the production of PTX3 have not been elucidated. In this study, we found that P. aeruginosa DnaK, a homolog of heat shock protein 70, induced PTX3 production. Induction was mediated by intracellular signals transmitted through the Toll-like receptor 4 (TLR4) signaling pathway. Following receptor engagement, the stimulatory signals were relayed initially through the nuclear factor kappa B (NF-κB) signaling pathway and subsequently by extracellular signal-regulated kinases (ERK), which are mitogen-activated protein kinases. However, ERK activation was negatively controlled by NF-κB, implying the existence of negative crosstalk between the NF-κB and the ERK pathways. These data suggest that P. aeruginosa DnaK acts as a pathogen-associated molecular pattern to trigger modulation of host defense responses via production of PTX3.


Assuntos
Proteínas de Bactérias/metabolismo , Proteína C-Reativa/biossíntese , Interações entre Hospedeiro e Microrganismos/imunologia , Pseudomonas aeruginosa/patogenicidade , Componente Amiloide P Sérico/biossíntese , Alarminas/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Imunidade Inata , Sistema de Sinalização das MAP Quinases , NF-kappa B/metabolismo , Pseudomonas aeruginosa/imunologia , Pseudomonas aeruginosa/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Células THP-1 , Receptor 4 Toll-Like/metabolismo
4.
Int J Mol Sci ; 21(23)2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33276561

RESUMO

IL-27, a heterodimeric cytokine composed of the p28 subunit and Epstein-Barr virus-induced gene 3 (EBI3), acts as a potent immunosuppressant and thus limits pathogenic inflammatory responses. IL-27 is upregulated upon Pseudomonas aeruginosa infection in septic mice, increasing susceptibility to the infection and decreasing clearance of the pathogen. However, it remains unclear which P. aeruginosa-derived molecules promote production of IL-27. In this study, we explored the mechanism by which P. aeruginosa DnaK, a heat shock protein 70-like protein, induces EBI3 expression, thereby promoting production of IL-27. Upregulation of EBI3 expression did not lead to an increase in IL-35, which consists of the p35 subunit and EBI3. The IL-27 production in response to DnaK was biologically active, as reflected by stimulation of IL-10 production. DnaK-mediated expression of EBI3 was driven by two distinct signaling pathways, NF-κB and Akt. However, NF-κB is linked to TLR4-associated signaling pathways, whereas Akt is not. Taken together, our results reveal that P. aeruginosa DnaK potently upregulates EBI3 expression, which in turn drives production of the prominent anti-inflammatory cytokine IL-27, as a consequence of TLR4-dependent activation of NF-κB and TLR4-independent activation of the Akt signaling pathway.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Interleucina-27/biossíntese , Infecções por Pseudomonas/metabolismo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/metabolismo , Proteínas de Bactérias/genética , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Interações Hospedeiro-Patógeno , Interleucinas/genética , Interleucinas/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pseudomonas aeruginosa/genética , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
5.
Opt Express ; 25(7): 8036-8047, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28380926

RESUMO

We propose and demonstrate a system for wavefront shaping, which generates optical foci through complex disordered media and achieves an enhancement factor of greater than 100,000. To exploit the 1 megapixel capacity of a digital micro-mirror device and its fast frame rate, we developed a fast and efficient method to handle the heavy matrix algebra computation involved in optimizing the focus. We achieved an average enhancement factor of 101,391 within an optimization time of 73 minutes with amplitude control. This unprecedented enhancement factor may open new possibilities for realistic image projection and the efficient delivery of energy through scattering media.

6.
Opt Lett ; 41(8): 1837-40, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082358

RESUMO

We present a simple but effective method to measure the pressure inside a deformable microchannel using laser scattering in a translucent Scotch tape. Our idea exploits the fact that the speckle pattern generated by a turbid layer is sensitive to the changes in the optical wavefront of an impinging beam. A change in the internal pressure of a channel deforms the elastic channel, which can be detected by measuring the speckle patterns of a coherent laser beam that has passed through the channel and the Scotch tape. We demonstrate that with a proper calibration, internal pressure can be remotely sensed with the resolution of 0.1 kPa within a pressure range of 0-3 kPa after calibration.

7.
Opt Lett ; 40(8): 1667-70, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25872043

RESUMO

We demonstrate that polarization modulation of an illumination beam can effectively control the spatial profile of the light transmitted through turbid media. Since the transmitted electric fields are completely mingled in turbid media, polarization states of an illumination beam can be used effectively to control the propagation of light through turbid media. Numerical simulations were performed which agree with experimental results obtained using a commercial in-plane switching liquid crystal display for modulating the input polarization states.


Assuntos
Luz , Espalhamento de Radiação , Cristais Líquidos , Modelos Teóricos , Fenômenos Ópticos
8.
Opt Express ; 22(20): 24304-11, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25322005

RESUMO

We present measurements of the full Jones matrix of individual pixels in a liquid-crystal display (LCD) panel. Employing a polarization-sensitive digital holographic microscopy based on Mach-Zehnder interferometry, the complex amplitudes of the light passing through individual LCD pixels are precisely measured with respect to orthogonal bases of polarization states, from which the full Jones matrix components of individual pixels are obtained. We also measure the changes in the Jones matrix of individual LCD pixels with respect to an applied bias. In addition, the complex optical responses of a LCD panel with respect to arbitrary polarization states of incident light were characterized from the measured Jones matrix.

9.
Opt Express ; 22(7): 7514-23, 2014 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-24718125

RESUMO

We report the enhancement in the obtained signal and penetration depth of 2-D depth-resolved images that were taken by shaping the incident wavefront in optical coherence tomography (OCT). Limitations in the penetration depth and signal to noise ratio (SNR) in OCT are mainly due to multiple scattering, which have been effectively suppressed by controlling the incident wavefront using a digital mirror device (DMD) in combination with spectral-domain OCT. The successful enhancements in the penetration depth and SNR are demonstrated in a wide-range of tissue phantoms, reaching depth enhancement of up to 92%. The hidden structures inside a tissue phantom that could not be seen in conventional OCT are clearly revealed through our proposed system. Its 2-D imaging capability, assisted by further optimization of the system for real-time acquisition speed will boost wide-spread use of OCT for in-vivo tissue diagnosis.


Assuntos
Aumento da Imagem/instrumentação , Imagens de Fantasmas , Tomografia de Coerência Óptica/instrumentação , Desenho de Equipamento , Humanos
10.
Phys Rev Lett ; 113(11): 113901, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25259979

RESUMO

Light-matter interaction gives optical microscopes tremendous versatility compared with other imaging methods such as electron microscopes, scanning probe microscopes, or x-ray scattering where there are various limitations on sample preparation and where the methods are inapplicable to bioimaging with live cells. However, this comes at the expense of a limited resolution due to the diffraction limit. Here, we demonstrate a novel method utilizing elastic scattering from disordered nanoparticles to achieve subdiffraction limited imaging. The measured far-field speckle fields can be used to reconstruct the subwavelength details of the target by time reversal, which allows full-field dynamic super-resolution imaging. The fabrication of the scattering superlens is extremely simple and the method has no restrictions on the wavelength of light that is used.

11.
Appl Opt ; 53(27): G111-22, 2014 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-25322118

RESUMO

The identification and quantification of specific molecules are crucial for studying the pathophysiology of cells, tissues, and organs as well as diagnosis and treatment of diseases. Recent advances in holographic microspectroscopy, based on quantitative phase imaging or optical coherence tomography techniques, show promise for label-free noninvasive optical detection and quantification of specific molecules in living cells and tissues (e.g., hemoglobin protein). To provide important insight into the potential employment of holographic spectroscopy techniques in biological research and for related practical applications, we review the principles of holographic microspectroscopy techniques and highlight recent studies.


Assuntos
Biopolímeros/análise , Holografia/métodos , Imageamento Tridimensional/métodos , Microscopia de Contraste de Fase/métodos , Imagem Molecular/métodos , Análise Espectral/métodos , Tomografia de Coerência Óptica/métodos , Avaliação da Tecnologia Biomédica
12.
Opt Express ; 21(3): 2890-902, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23481747

RESUMO

We report on an approach to exploit multiple light scattering by shaping the incident wavefront in optical coherence tomography (OCT). Most of the reflected signal from biological tissue consists of multiply scattered light, which is regarded as noise in OCT. A digital mirror device (DMD) is utilized to shape the incident wavefront such that the maximal energy is focused at a specific depth in a highly scattering sample using a coherence-gated reflectance signal as feedback. The proof-of-concept experiment demonstrates that this approach enhances depth-selective focusing in the presence of optical inhomogeneity, and thus extends the penetration depth in spectral domain-OCT (SD-OCT).


Assuntos
Aumento da Imagem/instrumentação , Lentes , Processamento de Sinais Assistido por Computador/instrumentação , Tomografia de Coerência Óptica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Tomografia de Coerência Óptica/métodos
13.
Phys Rev Lett ; 111(15): 153902, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-24160602

RESUMO

We report a measurement of the large optical transmission matrix (TM) of a complex turbid medium. The TM is acquired using polarization-sensitive, full-field interferometric microscopy equipped with a rotating galvanometer mirror. It is represented with respect to input and output bases of optical modes, which correspond to plane wave components of the respective illumination and transmitted waves. The modes are sampled so finely in angular spectrum space that their number exceeds the total number of resolvable modes for the illuminated area of the sample. As such, we investigate the singular value spectrum of the TM in order to detect evidence of open transmission channels, predicted by random-matrix theory. Our results comport with theoretical expectations, given the experimental limitations of the system. We consider the impact of these limitations on the usefulness of transmission matrices in optical measurements.


Assuntos
Óptica e Fotônica/instrumentação , Óptica e Fotônica/métodos , Microscopia de Interferência/instrumentação , Microscopia de Interferência/métodos , Modelos Teóricos , Nanopartículas/química , Nefelometria e Turbidimetria , Teoria Quântica , Espalhamento de Radiação , Óxido de Zinco/química
14.
Nat Commun ; 14(1): 3534, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316495

RESUMO

While recent research has shown that holographic displays can represent photorealistic 3D holograms in real time, the difficulty in acquiring high-quality real-world holograms has limited the realization of holographic streaming systems. Incoherent holographic cameras, which record holograms under daylight conditions, are suitable candidates for real-world acquisition, as they prevent the safety issues associated with the use of lasers; however, these cameras are hindered by severe noise due to the optical imperfections of such systems. In this work, we develop a deep learning-based incoherent holographic camera system that can deliver visually enhanced holograms in real time. A neural network filters the noise in the captured holograms, maintaining a complex-valued hologram format throughout the whole process. Enabled by the computational efficiency of the proposed filtering strategy, we demonstrate a holographic streaming system integrating a holographic camera and holographic display, with the aim of developing the ultimate holographic ecosystem of the future.

15.
Opt Lett ; 37(13): 2577-9, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22743460

RESUMO

We present measurements of the scalar-field light scattering of individual dimer, trimer, and tetrahedron shapes among colloidal clusters. By measuring the electric field with quantitative phase imaging at the sample plane and then numerically propagating to the far-field scattering plane, the two-dimensional light-scattering patterns from individual colloidal clusters are effectively and precisely retrieved. The measured scattering patterns are consistent with simulated patterns calculated from the generalized multiparticle Mie solution.


Assuntos
Análise de Fourier , Luz , Polimetil Metacrilato/química , Espalhamento de Radiação , Coloides , Dimerização , Microscopia
16.
Nat Commun ; 13(1): 6012, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224198

RESUMO

Holography is one of the most prominent approaches to realize true-to-life reconstructions of objects. However, owing to the limited resolution of spatial light modulators compared to static holograms, reconstructed objects exhibit various coherent properties, such as content-dependent defocus blur and interference-induced noise. The coherent properties severely distort depth perception, the core of holographic displays to realize 3D scenes beyond 2D displays. Here, we propose a hologram that imitates defocus blur of incoherent light by engineering diffracted pattern of coherent light with adopting multi-plane holography, thereby offering real world-like defocus blur and photorealistic reconstruction. The proposed hologram is synthesized by optimizing a wave field to reconstruct numerous varifocal images after propagating the corresponding focal distances where the varifocal images are rendered using a physically-based renderer. Moreover, to reduce the computational costs associated with rendering and optimizing, we also demonstrate a network-based synthetic method that requires only an RGB-D image.

17.
IEEE Trans Vis Comput Graph ; 25(5): 1940-1950, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30794180

RESUMO

Multi-focal plane and multi-layered light-field displays are promising solutions for addressing all visual cues observed in the real world. Unfortunately, these devices usually require expensive optimizations to compute a suitable decomposition of the input light field or focal stack to drive individual display layers. Although these methods provide near-correct image reconstruction, a significant computational cost prevents real-time applications. A simple alternative is a linear blending strategy which decomposes a single 2D image using depth information. This method provides real-time performance, but it generates inaccurate results at occlusion boundaries and on glossy surfaces. This paper proposes a perception-based hybrid decomposition technique which combines the advantages of the above strategies and achieves both real-time performance and high-fidelity results. The fundamental idea is to apply expensive optimizations only in regions where it is perceptually superior, e.g., depth discontinuities at the fovea, and fall back to less costly linear blending otherwise. We present a complete, perception-informed analysis and model that locally determine which of the two strategies should be applied. The prediction is later utilized by our new synthesis method which performs the image decomposition. The results are analyzed and validated in user experiments on a custom multi-plane display.

18.
Sci Rep ; 7: 44435, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28322268

RESUMO

Here, we present a concept based on the realization that a complex medium can be used as a simple interferometer. Changes in the wavefront of an incident coherent beam can be retrieved by analyzing changes in speckle patterns when the beam passes through a light diffuser. We demonstrate that the spatial intensity correlations of the speckle patterns are independent of the light diffusers, and are solely determined by the phase changes of an incident beam. With numerical simulations using the random matrix theory, and an experimental pressure-driven wavefront-deforming setup using a microfluidic channel, we theoretically and experimentally confirm the universal sensitivity of speckle intensity correlations, which is attributed to the conservation of optical field correlation despite multiple light scattering. This work demonstrates that a light diffuser works as a simple interferometer, and presents opportunities to retrieve phase information of optical fields with a compact scattering layer in various applications in metrology, analytical chemistry, and biomedicine.

19.
J Biomed Opt ; 21(12): 121510, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27792807

RESUMO

We demonstrate that simultaneous application of optical clearing agents (OCAs) and complex wavefront shaping in optical coherence tomography (OCT) can provide significant enhancement of penetration depth and imaging quality. OCA reduces optical inhomogeneity of a highly scattering sample, and the wavefront shaping of illumination light controls multiple scattering, resulting in an enhancement of the penetration depth and signal-to-noise ratio. A tissue phantom study shows that concurrent applications of OCA and wavefront shaping successfully operate in OCT imaging. The penetration depth enhancement is further demonstrated for

Assuntos
Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Animais , Meios de Contraste , Orelha/diagnóstico por imagem , Desenho de Equipamento , Glicerol , Camundongos , Imagens de Fantasmas , Reprodutibilidade dos Testes
20.
J Biomed Opt ; 21(10): 101406, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26895566

RESUMO

Multiple light scattering in tissue limits the penetration of optical coherence tomography (OCT) imaging. Here, we present in vivo OCT imaging of a live mouse using wavefront shaping (WS) to enhance the penetration depth. A digital micromirror device was used in a spectral-domain OCT system for complex WS of an incident beam which resulted in the optimal delivery of light energy into deep tissue. Ex vivo imaging of chicken breasts and mouse ear tissues showed enhancements in the strength of the image signals and the penetration depth, and in vivo imaging of the tail of a live mouse provided a multilayered structure inside the tissue.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Processamento de Sinais Assistido por Computador , Tomografia de Coerência Óptica/métodos , Animais , Galinhas , Orelha/fisiologia , Camundongos , Músculos/fisiologia , Espalhamento de Radiação
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