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BACKGROUND & AIMS: Colorectal cancer is a leading cause of cancer death, and a major risk factor is chronic inflammation. Despite the link between colitis and cancer, the mechanism by which inflammation leads to colorectal cancer is not well understood. METHODS: To investigate whether different forms of inflammation pose the same risk of cancer, we compared several murine models of colitis (dextran sodium sulfate [DSS], 2,4,6-trinitrobenzene sulfonic acid, 4-ethoxylmethylene-2-phenyloxazol-5-one, Citrobacter rodentium, Fusobacterium nucleatum, and doxorubicin) with respect to their ability to lead to colonic tumorigenesis. We attempted to correlate the severity of colitis and inflammatory profile with the risk of tumorigenesis in both azoxymethane-dependent and Dclk1/APCfl/fl murine models of colitis-associated cancer. RESULTS: DSS colitis reproducibly led to colonic tumors in both mouse models of colitis-associated cancer. In contrast, all other forms of colitis did not lead to cancer. When compared with the colitis not associated with tumorigenesis, DSS colitis was characterized by significantly increased CD11b+F4/80+Ly6Chigh macrophages and CD11b+Ly6G+ neutrophils. Interestingly, depletion of the CD11b+F4/80+Ly6Chigh macrophages inhibited tumorigenesis, whereas depletion of CD11b+Ly6G+ neutrophils had no effect on tumorigenesis. Furthermore, the macrophage-derived cytokines interleukin-1ß, tumor necrosis factor-α, and interleukin-6 were significantly increased in DSS colitis and promoted stemness of Dclk1+ tuft cells that serve as the cellular origin of cancer. CONCLUSIONS: We have identified CD11b+F4/80+Ly6Chigh macrophages as key mediators of cancer initiation in colitis-associated cancer. Development of new therapies that target these cells may provide an effective preventative strategy for colitis-associated cancer.
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Neoplasias Associadas a Colite , Colite , Animais , Camundongos , Azoximetano , Carcinogênese/metabolismo , Plasticidade Celular , Colite/induzido quimicamente , Colite/complicações , Colite/metabolismo , Neoplasias Associadas a Colite/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Hypersonic target detection based on infrared intensity characteristics is easily disturbed by sea surface and cloud flares when detected by space-based optical systems, which results in a low detection rate, high false alarm, and difficulty in stable detection. This paper explores a method to improve target detection performance based on the correlation of infrared radiation, multi-spectral and polarization. Firstly, the comprehensive factors that influence complex ambient illumination, atmospheric transmission, and clutter background on spectral-polarization characteristics of hypersonic targets are analyzed. Based on the global radiation scattering theory, the temperature distribution model of the hypersonic target is established by using FLUENT. The polarization emission and pBRDF model of the target is established, and the radiation polarization transfer model is generated. Secondly, the sea surface temperature distribution is obtained by inversion of Landsat8 remote sensing data. The radiation polarization transfer model of the sea surface is established based on the Cox-Munk model combined with pBRDF and the polarization emission model. Thirdly, the polarization scattering effect of atmospheric particles on the upward radiation of the interaction of the target with the sunlight is considered comprehensively, and the 6SV radiative transfer model is used to calculate the polarization effect of atmospheric particles on the upward radiation transmission of the target and the background. Then, combined with the point diffusion of the optical system and the photoelectric conversion of the detector, the multi-dimensional full-chain imaging prediction model of the hypersonic target-sea background-ambient atmosphere-optical system-detector is established. The imaging characteristics and detection performance of the target in different imaging dimensions are simulated and analyzed with the signal-to-clutter ratio (SCR). The research shows that in the direction of reflected sunlight from the sea surface, the sea surface glare is suppressed and the target is highlighted through a target detection method of multi-dimensional information. This method has better detection results than the infrared multi-spectral detection method.
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We report a structure of silicon eccentric shell particles array, fabricated by the SiO2particles monolayer array assisted deposition of amorphous Si, for high-efficiency light confinement. The SiO2particles monolayer array is tailored to regulate its interparticle distance, followed by silicon film deposition to obtain silicon eccentric shell arrays with positive and negative off-center distancee. We studied the Mie resonances of silicon solid sphere, concentric shell, eccentric shell and observed that the eccentric shell with positive off-centeresupports superior light confinement because of the enhanced Mie magnetic resonances. Spectroscopic measurements and finite difference time domain simulations were conducted to examine the optical performance of the eccentric shell particles array. Results show that the Mie magnetic resonance wavelength can be easily regulated by the size of the inner void of the silicon shell to realize tunable enhanced light confinement. It was found silicon shell withD= 460/520 nm offered high enhanced light absorption efficiency at wavelength ofλ= 830 nm, almost beyond the bandgap of the amorphous silicon.
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Fusobacterium nucleatum (Fn) is a Gram-negative oral commensal, prevalent in various human diseases. It is unknown how this common commensal converts to a rampant pathogen. We report that Fn secretes an adhesin (FadA) with amyloid properties via a Fap2-like autotransporter to enhance its virulence. The extracellular FadA binds Congo Red, Thioflavin-T, and antibodies raised against human amyloid ß42. Fn produces amyloid-like FadA under stress and disease conditions, but not in healthy sites or tissues. It functions as a scaffold for biofilm formation, confers acid tolerance, and mediates Fn binding to host cells. Furthermore, amyloid-like FadA induces periodontal bone loss and promotes CRC progression in mice, with virulence attenuated by amyloid-binding compounds. The uncleaved signal peptide of FadA is required for the formation and stability of mature amyloid FadA fibrils. We propose a model in which hydrophobic signal peptides serve as "hooks" to crosslink neighboring FadA filaments to form a stable amyloid-like structure. Our study provides a potential mechanistic link between periodontal disease and CRC and suggests anti-amyloid therapies as possible interventions for Fn-mediated disease processes.
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Adesinas Bacterianas , Fusobacterium nucleatum , Adesinas Bacterianas/metabolismo , Animais , Transporte Biológico , Camundongos , Sinais Direcionadores de Proteínas , VirulênciaRESUMO
An analytical expression for a partially coherent azimuthally polarized beam with an astigmatic phase (PCAPBAP) is derived. The statistical properties of the PCAPBAP propagating in a paraxial-focused system are studied through numerical examples. It is shown that the beam's shape changes in a unique way during propagation, and this type of change is related to the rotating factor of the astigmatic phase. Moreover, the influence of the rotating factor and source coherence length on the beam's polarization and coherence is investigated in detail. The results show that the coherence and polarization properties of the beam also change obviously due to the astigmatic phase's effect. This paper will be helpful to the fields of optical tweezers, optical needles, imaging, and so on.
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The terahertz band is considered to be the next breakthrough point to revolutionize communication technology, attributed to its rich spectrum resources. The study of terahertz atmospheric transmission characteristics is important in guiding the terahertz communication window selection process. In this report, based on the equivalent medium theory, the scattering characteristics of terahertz Gaussian beams by moist media are discussed. Numerical results show that the extinction coefficient of particles is mainly affected by the humidity, and the scattering efficiency is affected by both temperature and humidity. When the temperature is over 273 K and the humidity is 0.5, the extinction efficiency shows a trend of increasing initially and decreasing afterwards. Hence, the appropriate temperature is beneficial to minimizing the attenuation coefficient.
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Structural health monitoring is currently a crucial measure for the analysis of structural safety. As a structural asset management approach, it can provide a cost-effective measure and has been used successfully in a variety of structures. In recent years, the development of fiber optic sensing technology and vision sensing technology has led to further advances in structural health monitoring. This paper focuses on the basic principles, recent advances, and current status of applications of these two sensing technologies. It provides the reader with a broad review of the literature. It introduces the advantages, limitations, and future directions of these two sensing technologies. In addition, the main contribution of this paper is that the integration of fiber optic sensing technology and vision sensing technology is discussed. This paper demonstrates the feasibility and application potential of this integration by citing numerous examples. The conclusions show that this new integrated sensing technology can effectively utilize the advantages of both fields.
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With the help of generalized Huygens-Fresnel integral, an analytical expression for the self-healing of a partially coherent radially polarized twisted (PCRPT) beam is derived. The coherence and polarization properties of the PCRPT beam in self-healing propagation are studied in detail. It shows that the existence of the twist phase is a double-edged sword for the self-healing properties of the beam. With the increase of the twist factor, the self-healing ability of beam intensity distribution decreases. However, the anti-disturbance performance of beam polarization improves at the same time. Besides, the polarization and coherence distribution of the beam are proved that own a slight self-healing ability when the obstacle is small. Our results will be helpful to the fields of optical tweezers, microscopy, optical communication, and so on.
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The link between oral health and adverse pregnancy outcomes has been suggested by numerous epidemiological studies. More recent studies indicate the relationship between severity of periodontal disease and adverse pregnancy outcomes. Two virulence mechanisms are proposed: direct invasion of oral microorganisms or their components into the fetal-placenta unit and inflammatory mediators produced in the oral cavity affecting the fetal-placenta unit. While interventional periodontal therapy still yielded contradictory results, animal studies suggest that maternal supplementation of omega-3 fatty acids protects the fetus by suppressing inflammation as well as bacteria proliferation in the placenta. This article reviews the recent epidemiological, mechanistic, interventional, and therapeutic studies of oral health and adverse pregnancy outcomes.
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Doenças Periodontais , Resultado da Gravidez , Animais , Feminino , Fusobacterium nucleatum , Humanos , Saúde Bucal , Doenças Periodontais/microbiologia , Doenças Periodontais/terapia , Porphyromonas gingivalis , GravidezRESUMO
In this work, we report an implementation of typical structured light beams, including the Hermite-Gaussian beams, Laguerre-Gaussian beams, Bessel beams, and Airy beams, in the discrete dipole approximation (DDA) for scattering problems of small particles. The analytical expressions for the electric field components of these beams are presented, and the detailed processes for the implementation of these beams in DDA are given, with particular emphasis on the explicit codes. The calculated result for our codes of Gaussian beams is compared with that from the Amsterdam DDA codes, and very good agreement is observed. The internal and near-surface fields of a sphere illuminated by the typical structured light beams with different beam parameters are illustrated and discussed. Also, the intensity distributions of internal and near-surface fields as well as the scattering efficiency factor for the scattering of structured light beams as mentioned above by sphere, spheroid, and cylinder are presented. The proposed codes can be directly used for the investigation of scattering of typical structured light beams by complex particles within the framework of the DDA.
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Compared to the experimental progresses made in the optical trapping of aerosol particles in gaseous media by means of photophoretic forces, the theoretical analysis of photophoretic forces is less developed, the underlying mechanisms being yet not fully understood. In this paper, theoretical derivations of photopheresis of a dielectric sphere in gaseous media illuminated by a circularly symmetric Bessel beam of arbitrary order is presented within the framework of generalized Lorenz-Mie theory. An analytic and closed-form formula for the asymmetry factor, which ultimately determines the sense of direction of photophoretic force, is provided. The influences of particle size, absorptivity of the particle, half-cone angle, beam order of the Bessel beam on the asymmetry factor are explored in detail. The method proposed in this paper can be applied to a wider class of axisymmetric beams carrying nonzero topological charges.
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Fusobacterium nucleatum, a Gram-negative oral anaerobe, is a significant contributor to colorectal cancer. Using an in vitro cancer progression model, we discover that F. nucleatum stimulates the growth of colorectal cancer cells without affecting the pre-cancerous adenoma cells. Annexin A1, a previously unrecognized modulator of Wnt/ß-catenin signaling, is a key component through which F. nucleatum exerts its stimulatory effect. Annexin A1 is specifically expressed in proliferating colorectal cancer cells and involved in activation of Cyclin D1. Its expression level in colon cancer is a predictor of poor prognosis independent of cancer stage, grade, age, and sex. The FadA adhesin from F. nucleatum up-regulates Annexin A1 expression through E-cadherin. A positive feedback loop between FadA and Annexin A1 is identified in the cancerous cells, absent in the non-cancerous cells. We therefore propose a "two-hit" model in colorectal carcinogenesis, with somatic mutation(s) serving as the first hit, and F. nucleatum as the second hit exacerbating cancer progression after benign cells become cancerous. This model extends the "adenoma-carcinoma" model and identifies microbes such as F. nucleatum as cancer "facilitators".
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Anexina A1/metabolismo , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , Infecções por Fusobacterium/complicações , Infecções por Fusobacterium/microbiologia , Fusobacterium nucleatum/fisiologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Retroalimentação Fisiológica , Xenoenxertos , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Modelos Biológicos , Prognóstico , Ligação Proteica , Transdução de SinaisRESUMO
Laguerre-Gaussian (LG) beams with vortex phase possess a handedness, which would produce chiroptical interactions with chiral matter and may be used to probe structural chirality of matter. In this paper, we numerically investigate the light scattering of LG vortex beams by chiral particles. Using the vector potential method, the electric and magnetic field components of the incident LG vortex beams are derived. The method of moments (MoM) based on surface integral equations (SIEs) is applied to solve the scattering problems involving arbitrarily shaped chiral particles. The numerical results for the differential scattering cross sections (DSCSs) of several selected chiral particles illuminated by LG vortex beams are presented and analyzed. In particular, we show how the DSCSs depend on the chiral parameter of the particles and on the parameters describing the incident LG vortex beams, including the topological charge, the state of circular polarization, and the beam waist. This research may provide useful insights into the interaction of vortex beams with chiral particles and its further applications.
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BACKGROUND: Ischemia reperfusion injury (I/RI) is a common complication of cardiovascular diseases. Resolution of detrimental I/RI-generated prothrombotic and proinflammatory responses is essential to restore homeostasis. Platelets play a crucial part in the integration of thrombosis and inflammation. Their role as participants in the resolution of thromboinflammation is underappreciated; therefore we used pharmacological and genetic approaches, coupled with murine and clinical samples, to uncover key concepts underlying this role. METHODS: Middle cerebral artery occlusion with reperfusion was performed in wild-type or annexin A1 (AnxA1) knockout (AnxA1-/-) mice. Fluorescence intravital microscopy was used to visualize cellular trafficking and to monitor light/dye-induced thrombosis. The mice were treated with vehicle, AnxA1 (3.3 mg/kg), WRW4 (1.8 mg/kg), or all 3, and the effect of AnxA1 was determined in vivo and in vitro. RESULTS: Intravital microscopy revealed heightened platelet adherence and aggregate formation post I/RI, which were further exacerbated in AnxA1-/- mice. AnxA1 administration regulated platelet function directly (eg, via reducing thromboxane B2 and modulating phosphatidylserine expression) to promote cerebral protection post-I/RI and act as an effective preventative strategy for stroke by reducing platelet activation, aggregate formation, and cerebral thrombosis, a prerequisite for ischemic stroke. To translate these findings into a clinical setting, we show that AnxA1 plasma levels are reduced in human and murine stroke and that AnxA1 is able to act on human platelets, suppressing classic thrombin-induced inside-out signaling events (eg, Akt activation, intracellular calcium release, and Ras-associated protein 1 [Rap1] expression) to decrease αIIbß3 activation without altering its surface expression. AnxA1 also selectively modifies cell surface determinants (eg, phosphatidylserine) to promote platelet phagocytosis by neutrophils, thereby driving active resolution. (n=5-13 mice/group or 7-10 humans/group.) Conclusions: AnxA1 affords protection by altering the platelet phenotype in cerebral I/RI from propathogenic to regulatory and reducing the propensity for platelets to aggregate and cause thrombosis by affecting integrin (αIIbß3) activation, a previously unknown phenomenon. Thus, our data reveal a novel multifaceted role for AnxA1 to act both as a therapeutic and a prophylactic drug via its ability to promote endogenous proresolving, antithromboinflammatory circuits in cerebral I/RI. Collectively, these results further advance our knowledge and understanding in the field of platelet and resolution biology.
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Anexina A1/genética , Plaquetas/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Inflamação/genética , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Transdução de SinaisRESUMO
The phytohormone abscisic acid (ABA) is produced via a multistep de novo biosynthesis pathway or via single-step hydrolysis of inactive ABA-glucose ester (ABA-GE). The hydrolysis reaction is catalyzed by ß-glucosidase (BG, or BGLU) isoforms localized to various organelles, where they become activated upon stress, but the mechanisms underlying this organelle-specific activation remain unclear. We investigated the relationship between the subcellular distribution and stress-induced activation of BGLU18 (BG1), an endoplasmic reticulum enzyme critical for abiotic stress responses, in Arabidopsis thaliana leaves. High BGLU18 levels were present in leaf petioles, primarily in endoplasmic reticulum bodies. These Brassicaceae-specific endoplasmic reticulum-derived organelles responded dynamically to abiotic stress, particularly drought-induced dehydration, by changing in number and size. Under stress, BGLU18 distribution shifted toward microsomes, which was accompanied by increasing BGLU18-mediated ABA-GE hydrolytic activity and ABA levels in leaf petioles. Under non-stress conditions, impaired endoplasmic reticulum body formation caused a microsomal shift of BGLU18 and increased its enzyme activity; however, ABA levels increased only under stress, probably because ABA-GE is supplied to the endoplasmic reticulum only under these conditions. Loss of BGLU18 delayed dehydration-induced ABA accumulation, suggesting that ABA-GE hydrolysis precedes the biosynthesis. We propose that dynamics of the endoplasmic reticulum modulate ABA homeostasis and abiotic stress responses by activating BGLU18-mediated ABA-GE hydrolysis.
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Ácido Abscísico , Proteínas de Arabidopsis , Proteínas de Arabidopsis/metabolismo , Retículo Endoplasmático/metabolismo , Ésteres , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Estresse Fisiológico , beta-Glucosidase/genéticaRESUMO
Adverse pregnancy outcomes (APOs) have been defined as (a) pre-term birth, when there is a delivery before 37 completed weeks (<259 days); (b) pre-eclampsia, which is a multisystem disorder of pregnancy characterized by maternal hypertension and proteinuria after the 20th gestational week; (c) low and very low birthweight, depending on whether the weight of the baby is less of 2500 g or <1500 g and (d) the spontaneous death of the fetus with <20 weeks (miscarriage) or between 20 and 36 weeks (stillbirth). In 2012, during the Consensus Report from the Joint EFP/AAP workshop on periodontitis and systematic diseases the role of periodontal diseases on APOs was reviewed. Some years later, this evidence has grown, and an update on the literature regarding the mechanisms related to this potential association (APOs and periodontal diseases) needs to be presented. The two major pathways (direct and indirect) already accepted in 2012 are still valid nowadays. Most evidence published in the last 5 years deals with a strong and solid evidence coming from the direct pathway while there is as scarce new evidence regarding indirect pathway. In this direct pathway, the haematological dissemination of oral microorganisms and their products, would later induce an inflammatory/Immune response in the foetal-placental unit. The most plausible route for this direct pathway is the hematogenous transmission through dental bacteremia, although not many new studies dealing with bacteremia has been performed lately.
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Doenças Periodontais , Periodontite , Complicações na Gravidez , Nascimento Prematuro , Feminino , Humanos , Gravidez , Resultado da GravidezRESUMO
As a kind of typical self-accelerating laser beam, Airy beams have attracted much attention due to their fascinating properties and various potential applications. In this work, we carry out a full vector wave analysis of Airy beams upon reflection and refraction. A hybrid method based on the angular spectrum representation and vector potential in the Lorenz gauge is introduced to describe the vectorial structure of Airy beams upon reflection and refraction. The explicit analytical expressions for the electric and magnetic field components of arbitrarily incident Airy beams reflected and refracted at an air-medium interface are derived in detail. Local-field patterns and magnitude profiles with different parameters are displayed. The analytical formulas obtained in this work can be practically applied to explore the local dynamical characteristics, including the energy, momentum, spin, and orbital angular momentum of Airy beams upon reflection and refraction.
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Photonic jets (PJs) formed on the shadow side of micro-sized dielectric spheres excited by focused Gaussian beams are investigated within the framework of the generalized Lorenz-Mie theory (GLMT). The intrinsic advantages of rapidity and high accuracy of the GLMT in calculations enable us to conduct a systematic study of PJs at a low cost and a high reliability. To reveal the influence of beam parameters on the properties of PJs, numerical results concerning variations of key parameters of PJs, including the maximal intensity, the focal distance, which is linked to the position of maximal intensity, and longitudinal and transversal dimensions are presented with the change of the beam waist radius and the focal center location of the Gaussian beam. The results show that as the beam waist radius approaches the radius of the particle, the energy stream of the Gaussian beam contributes more efficiently to the formation of PJs. By properly tuning the location of the beam focal center, the PJ pattern can be efficiently engineered to a large extent.
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For practical wireless communication links, one of the critical challenges is the random fluctuation of turbulence that will impair link performance. Here a transmission model of partially coherent elegant Laguerre-Gaussian (ELG) beams in oceanic turbulence is established. An analytical formula for channel capacity of a partially coherent ELG beam propagating through a turbulent ocean is derived. The effects of oceanic turbulence on the evolution of channel capacity performance are studied quantitatively in a series of numerical simulations. Research results show that decreasing the rate of dissipation of mean-square temperature and ratio of temperature to salinity, as well as increasing the dissipation rate of turbulent kinetic energy per unit mass of fluid of a turbulent ocean can significantly improve communication channel capacity. Furthermore, choosing optimum beam source parameters is favorable to mitigate the influence of oceanic turbulence. Results also show that in the underwater turbulence, the partially coherent ELG beams are more affected by turbulence as compared to the fully coherent ELG beams. These study results may provide potential help in designing the free-space optical vortex communication systems.
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In this paper, the nondiffracting Bessel beam sources are implemented in finite-difference time-domain (FDTD) method. The high-order scattered-field algorithm of the FDTD (SF-FDTD (2, 4)) method is employed to investigate the scattering of particles illuminated by Bessel beams. In the SF-FDTD (2, 4) method, the scattered fields of the whole region are calculated directly by time stepping and the incident fields are obtained by the vector expressions of the diffraction-free Bessel beam. Some numerical results are included to illustrate the validity and capability of the proposed method. This study is expected to provide a new efficient method to investigate the interactions between nondiffracting beams and complex particles.