望春花(M.biondi)花提取物缓解UVB导致皮肤损伤的作用研究

富含木兰脂素的望春花(M.biondi)花提取物(MB)被用来研究其缓解紫外线导致的皮肤损伤作用。在中波紫外线(UVB)诱导的人永生化表皮细胞(HaCaT)和以UVB诱导的HaCaT细胞培养上清液作为刺激物诱导的血管内皮细胞(HUVEC)上,通过免疫荧光染色、酶联免疫吸附法检测细胞损伤下的不同关键指标的变化。结果显示,HaCaT细胞经UVB照射后16~72 h,环丁烷嘧啶二聚体(CPD)产生量显著升高,高迁移率族蛋白B1(HMGB1)表达上升,且逐步从细胞核迁移至细胞质,热休克家族蛋白27(Hsp27)表达量也上升,同时白介素6(IL-6)、白介素8(IL-8)、前列腺素E2(PGE-2)的表达量显著增加。而HaCaT细胞培养上清液刺激HUVEC细胞24 h后,内皮素-1(ET-1)、细胞间粘附分子-1(ICAM-1)表达量均显著升高。0.1%~0.5%的MB同步处理下,可显著抑制HaCaT细胞中CPD的产生量、HMGB1的表达量,减少HMGB1的核转移,促进Hsp27的表达,降低细胞因子的表达量,同时可显著减少HUVEC细胞中的ET-1,ICAM-1表达量。因此,MB可通过降低DNA损伤,减少HMGB1的合成与核转移,减少细胞因子表达量,降低血管通透性,来缓解皮肤受到紫外线照射后的损伤作用。

植物复合舒缓剂(CAP)对外源性皮肤刺激的保护作用

作为抵御外部环境的第一道防线,皮肤不仅是一种物理屏障,而且是一种具有多种免疫细胞的免疫器官。这些免疫细胞在不同的皮肤层中组织结构良好,并与非免疫结构细胞(如角质形成细胞)建立通信网络,参与先天和适应性免疫反应,以确保皮肤免疫稳态。通过探讨皮肤免疫反应的起始感知、初始传递、初级效应阶段下不同类型细胞所产生的关键调节剂来研究植物复合舒缓剂(CAP)对外源性皮肤刺激的潜在保护作用及机制。同时,利用三维(3D)重建的人类表皮模型(EpiKutis)来模拟弱屏障下的皮肤免疫反应研究CAP在组织层面的作用。结果显示,在外源性刺激时,关键免疫调节因子如胸腺基质淋巴细胞生成素(TSLP)、白细胞介素-8(IL-8)、前列腺素E2(PGE-2)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)在角质形成细胞、3D EpiKutis模型、THP-1衍生细胞和肥大细胞中含量均显著升高,而CAP同步处理下可显著降低这些因子的表达量。此外,CAP剂量依赖性地改善由Poly(I:C)和LPS诱导导致的丝聚蛋白降低。结果表明,CAP通过促进皮肤屏障修复,调控皮肤免疫反应的起始、传递和效应阶段发挥重要作用。

青皮提取物缓解皮肤敏感的作用机制研究

青皮提取物(CR)是将未成熟的柑橘幼果经过特定工艺制备而成,富含黄酮和生物碱。本项目通过瞬时电位受体香草酸亚型1(TRPV1)高表达细胞、前列腺素受体1(EP1)高表达细胞、神经母细胞,研究CR通过TRPV1缓解皮肤敏感的作用机制。于TRPV1高表达细胞和正常细胞上对比研究发现,辣椒素(CAP)、苯氧乙醇可通过激活TRPV1引起伤害性细胞因子白介素8、趋化因子MCP-1、前列腺素E2(PGE-2)的表达量增加,细胞划痕损伤后的迁移速度下降。而CR能显著降低细胞因子的过表达,特别是针对PGE-2,也可加速划痕损伤后的细胞迁移。再对PGE-2-EP1信号通路进行研究发现,0.5%体积分数的CR也可显著抑制PGE-2通过其受体EP1引发的荧光素酶激活。最后于神经母细胞上进行验证,发现0.06%~0.25%体积分数的CR也能抑制CAP、苯氧乙醇通过激活TRPV1导致的细胞外Ca^(2+)内流,进而抑制皮肤敏感或受刺激后的信号传导,最终缓解皮肤热、痒、痛等症状。因此,CR可通过调控TRPV1激活,进而抑制伤害性细胞因子分泌及下游信号传导,促进皮肤屏障修复,缓解皮肤因受到外界刺激过度反应后,导致的敏感和刺激。

Large aperture and non-critical phase-matched fourth harmonic generation of Nd:Glass lasers

A fourth harmonic generation(FHG)scheme in focusing beams is proposed and demonstrated for large aperture Nd:glass laser facilities.By placing the focusing lens before the FHG crystal,the problem of ultraviolet damage can be overcome,largely without affecting FHG conversion efficiency owing to the large angular acceptance of the non-critical phase matching technique.A numerical simulation of the FHG process indicates that angular acceptance can be appropriately increased by lowering the working temperature and jointing the two adjacent compensating angles,so that FHG in focusing beams with relatively small F numbers becomes feasible.With a 170mm3170mm37mmand 65%deuterated potassium dihydrogen phosphate crystal mounted in a high-precision,temperature-controlled system,high-efficiency FHG has been demonstrated in the focusing beam with a full beam convergence angle of 36 mrad.When driven with a 223 J,second harmonic radiation(2ω),1 ns flat-top pulse with a beam area of 130 cm2,corresponding to 1.7 GW/cm22ωinput intensity,182 J of fourth harmonic radiation(4ω)were generated.

桃树脂提取物的抗衰老功效研究

皮肤老化由多种因素引起,主要包括年龄导致的自然老化和暴露于环境导致的光老化。大气中的紫外线、雾霾中的多环芳烃均能造成皮肤炎症、细胞活性和功能下降,最终导致皮肤松弛、老化,形成皱纹、斑点。本研究以桃树脂提取物(PG)为研究对象,通过多种方法对其紧致、抗皱的功效进行研究。结果显示,在成纤维细胞衰老模型上,PG在质量分数为0.3%~10%的范围下能剂量依赖性地促进成纤维细胞增殖、Ⅰ型胶原蛋白合成,降低β-半乳糖苷酶的活性。在紫外线(UVA)和雾霾类似物苯并芘(BaP)造成的角质形成细胞衰老模型上,质量分数为0.1%~10%的PG可以抑制细胞因子前列腺素E2和基质金属蛋白酶1表达,恢复细胞活性,并降低β-半乳糖苷酶的活性。在人体临床评价上,质量分数为2%~10%的PG具有显著的即时提升皮肤含水量、降低经皮失水率、提升紧肤感、减少皱纹效果。PG作为一种天然来源的活性原料,可应用于皮肤保湿、紧致、抗皱系列产品中。

Broadband photonic structures for quantum light sources

Quantum light sources serve as one of the key elements in quantum photonic technologies. Such sources made from semiconductor material, e.g., quantum dots (QDs), are particularly appealing because of their great potential of scalability enabled by the modern planar nanofabrication technologies. So far, non-classic light sources based on semiconductor QDs are currently outperforming their counterparts using nonlinear optical process, for instance, parametric down conversion and four-wave mixing. To fully exploring the potential of semiconductor QDs, it is highly desirable to integrate QDs with a variety of photonic nanostructures for better device performance due to the improved light-matter interaction. Among different designs, the photonic nanostructures exhibiting broad operation spectral range is particularly interesting to overcome the QD spectral inhomogeneity and exciton fine structure splitting for the generations of single-photon and entangled photon pair respectively. In this review, we focus on recent progress on high-performance semiconductor quantum light sources that is achieved by integrating single QDs with a variety of broadband photonic nanostructures i.e. waveguide, lens and low-Q cavity.

Controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force of femtosecond laser pulses

Nanoparticles made of different materials usually support optical resonances in the visible to near infrared spectral range,such as the localized surface plasmons observed in metallic nanoparticles and the Mie resonances observed in dielectric ones.Such optical resonances,which are important for practical applications,depend strongly on the morphologies of nanoparticles.Laser irradiation is a simple but effective way to modify such optical resonances through the change in the morphology of a nanoparticle.Although laser-induced shaping of metallic nanoparticles has been successfully demonstrated,it remains a big challenge for dielectric nanoparticles due to their larger Young’s modulus and smaller thermal conductivities.Here,we proposed and demonstrated a strategy for realizing controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force induced by femtosecond laser pulses.It was found that both Si and Ge nanoparticles can be lit up by resonantly exciting the optical resonances with femtosecond laser pulses,leading to the luminescence burst when the laser power exceeds a threshold.In addition,the morphologies of Si and Ge nanoparticles can be modified by utilizing the giant absorption force exerted on them and the reduced Young’s modulus at high temperatures.The shape transformation from sphere to ellipsoid can be realized by laser irradiation,leading to the blueshifts of the optical resonances.It was found that Si and Ge nanoparticles were generally elongated along the direction parallel to the polarization of the laser light.Controllable shaping of Si and Ge can be achieved by deliberately adjusting the excitation wavelength and the laser power.Our findings are helpful for understanding the giant absorption force of femtosecond laser light and are useful for designing nanoscale photonic devices based on shaped highindex nanoparticles.

Metasurface-enabled polarization-independent LCoS spatial light modulator for 4K resolution and beyond

With the distinct advantages of high resolution,small pixel size,and multi-level pure phase modulation,liquid crystal on silicon(LCoS)devices afford precise and reconfigurable spatial light modulation that enables versatile applications ranging from micro-displays to optical communications.However,LCoS devices suffer from a long-standing problem of polarization-dependent response in that they only perform phase modulation on one linear polarization of light,and polarization-independent phase modulation-essential for most applications-have had to use complicated polarization-diversity optics.We propose and demonstrate,for the first time,an LCos device that directly achieves high-performance polarization-independent phase modulation at telecommunication wavelengths with 4K resolution and beyond by embedding a polarization-rotating metasurface between the LCoS backplane and the liquid crystal phase-modulating layer.We verify the device with a number of typical polarization-independent application functions including beam steering,holographical display,and in a key optical switching element-wavelength selective switch(WsS),demonstrating the significant benefits in terms of both configuration simplification and performance improvement.

Whether and When Superhydrophobic/Superoleophobic Surfaces Are Fingerprint Repellent

Driven by the ever-increasing demand for fingerprint-resistant techniques in modern society,numerous researches have proposed to develop innovative antifingerprint coatings based on superhydrophobic/superoleophobic surface design.However,whether superhydrophobic/superoleophobic surfaces have favorable repellency to the microscopic fingerprint is in fact an open question.Here,we establish a reliable method that enables evaluating the antifingerprint capability of various surfaces in a quantitative way.We show that superhydrophobicity is irrelevant with fingerprint repellency.Regarding superoleophobic surfaces,two distinct wetting states of microscopic fingerprint residues,i.e.,the"repellent"and the“collapsed”states,are revealed.Only in the"repellent"state,in which the fingerprint residues remain atop surface textures upon being pressed,superoleophobic surfaces can bring about favorable antifingerprint repellency,which correlates positively with their receding contact angles.A finger-deformation-dependent intrusion mechanism is proposed to account for the formation of diferent fingerprint wetting states.Our findings offer important insights into the mechanism of fingerprint repellency and will help the design of high-performance antifingerprint surfaces for diverse applications.

Bias-drift-free Mach–Zehnder modulators based on a heterogeneous silicon and lithium niobate platform

Optical modulators have been and will continue to be essential devices for energy-and cost-efficient optical communication networks.Heterogeneous silicon and lithium niobate modulators have demonstrated promising performances of low optical loss,low drive voltage,and large modulation bandwidth.However,DC bias drift is a major drawback of optical modulators using lithium niobate as the active electro-optic material.Here,we demonstrate high-speed and bias-drift-free Mach–Zehnder modulators based on the heterogeneous silicon and lithium niobate platform.The devices combine stable thermo-optic DC biases in silicon and ultra-fast electro-optic modulation in lithium niobate,and exhibit a low insertion loss of 1.8 d B,a low half-wave voltage of 3 V,an electro-optic modulation bandwidth of at least 70 GHz,and modulation data rates up to 128 Gb/s.

Surface phase defects induced downstream laser intensity modulation in high-power laser facility

Optics surface phase defects induced intensity modulation in high-power laser facility for inertial confinement fusion research is studied. Calculations and experiments reveal an exact mapping of the modulation patterns and the optics damage spot distributions from the surface phase defects. Origins are discussed during the processes of optics manufacturing and diagnostics, revealing potential improvements for future optics manufacturing techniques and diagnostic index, which is meaningful for fusion level laser facility construction and its operation safety.