Programmable Chromism and Photoluminescence of Spiropyran-Based Liquid Crystalline Polymer with Tunable Glass Transition Temperature.

Spiropyran-based materials (SPBMs) can give responses to the stimulations induced by the light, heat, force, or pH, which have been used as triggers for many smart materials. Here, a cross-linkable SPBM containing mesogenic-units is synthesized, which is pale-colored, non-photoluminescent and non-mesogenic at a spiro form, but dark-colored, photoluminescent, and mesogenic at a merocyanine form. Moreover, the dynamic interconversion behavior of the form in the different chemical environments are distinct. Liquid crystalline polymers (LCPs) containing the SPBMs cross-linked via visible light, own a photoswitchable glass transition temperature (Tg ) and retain the switchable property; however, the SPBMs cross-linked via UV light will be locked at the MC state, because the molecular movement was frozen at the room temperature lower than the given Tg of the LCP. Thus, programmable chromism and photoluminescence based on the tunable Tg can be endowed to the functional materials prepared from the SPBMs.

LncRNA LEF1-AS1 promotes metastasis of prostatic carcinoma via the Wnt/ß-catenin pathway.

BACKGROUND: Long noncoding RNAs (lncRNAs) are important functional regulators of many biological processes of cancers. However, the mechanisms by which lncRNAs modulate androgen-independent prostate cancer (AIPC) development remain largely unknown. METHODS: Next-generation sequencing technology and RT-qPCR were used to assess LEF1-AS1 expression level in AIPC tissues and adjacent normal tissues. Functional in vitro experiments, including colony formation, EDU and transwell assays were performed to assess the role of LEF1-AS1 in AIPC. Xenograft assays were conducted to assess the effect of LEF1-AS1 on cell proliferation in vivo. Chromatin immunoprecipitation (ChIP) and RNA binding protein immunoprecipitation (RIP) assays were performed to elucidate the regulatory network of LEF1-AS1. RESULTS: The next-generation sequencing results showed that LEF1-AS1 is significantly overexpressed in AIPC. Furthermore, our RT-qPCR assay data showed that LEF1-AS1 is overexpressed in AIPC tissues. Functional experiments showed that LEF1-AS1 promotes the proliferation, migration, invasion and angiogenic ability of AIPC cells in vitro and tumour growth in vivo by recruiting the transcription factor C-myb to the promoter of FZD2, inducing its transcription. Furthermore, LEF1-AS1 was shown to function as a competing endogenous RNA (ceRNA) that sponges miR-328 to activate CD44. CONCLUSION: In summary, the results of our present study revealed that LEF1-AS1 acts as a tumour promoter in the progression of AIPC. Furthermore, the results revealed that LEF1-AS1 functions as a ceRNA and regulates Wnt/ß-catenin pathway activity via FZD2 and CD44. Our results provide new insights into the mechanism that links the function of LEF1-AS1 with AIPC and suggests that LEF1-AS1 may serve as a novel potential target for the improvement of AIPC therapy.

Chiral differentiation of limonene in chiral nematic liquid crystals.

Chirality is of great importance in physical and biological systems. It helps differentiate chemical reactions and physical processes. It was reported that the diffusion of mesogenic chiral guests in chiral nematic liquid crystal hosts profoundly depends on the chirality of the guest and host molecules. When the guest and host molecules have the same handedness, the diffusion is much faster than that when the guest and host molecules have the opposite handedness. In this paper, we report the discovery that chiral differentiation also exists in the diffusion of limonene, which is non-mesogenic in chiral nematic liquid crystals. The diffusion of l-limonene (right-handed) in chiral nematic liquid crystals with a right handed helical structure is faster than that of d-limonene (left-handed). This result might be important in understanding the effects of chirality on physical processes that take place in biological systems. In addition, this effect could be utilized for enantiomer separation in the pharmaceutical industry.

Image flickering-free polymer stabilized fringe field switching liquid crystal display.

Liquid crystal displays are the leading technology for flat panel displays. Their energy efficiency is low, however, due to the light absorption caused by polarizers and color filters and power consumption by driving circuitries. In displaying static images, their energy efficiency can be improved if a low driving frequency is used. As the driving frequency is decreased, the transmittance of the displays may change with time, a phenomenon known as image flickering. In this research we demonstrated that polymer stabilization can significantly reduce the flickering in fringe field switching (FFS) liquid crystal display. Under the polymer stabilization, the driving voltage remains low and the response time becomes shorter. Through simulation study, we find that the polymer stabilization smooths the spatial variation of the liquid crystal orientation in the display, and thus reduce the flexoelectric effect which is responsible for image flickering. The polymer stabilization can be implemented in the current main stream manufacturing to produce displays that can show static images under low power consumption.

Effect of biaxiality on chirality in chiral nematic liquid crystals.

Biaxiality and chirality are two of the most interesting topics in materials and biological science, particularly in liquid crystals. What is even more interesting is that these two properties are related. It was theoretically predicted that morphological chirality is impossible without morphological biaxiality in chiral nematic liquid crystals. We experimentally study the effect of biaxiality on chirality. We show that when achiral liquid crystal dimers with large molecular biaxiality are doped into chiral nematic liquid crystals, their helical pitch is significantly decreased. We have also observed an abnormal fingerprint texture of the chiral nematic liquid crystal doped dimers, which suggests morphological biaxiality. Our experimental results support the biaxial theory of chiral nematic liquid crystals.

Relationship Between SLC22A1 and SLC22A4 Gene Polymorphisms and Risk of Type 2 Diabetes in Chinese Han Population.

BACKGROUND: This study was to investigate the relationship between SLC22A1 and SLC22A4 gene polymorphisms and genetic susceptibility to type 2 diabetes in Chinese Han population. METHODS: The research group comprised 110 Chinese Han patients with type 2 diabetes, and the control group included 110 healthy volunteers. The polymorphisms of SLC22A1 gene rs628031 and rs2282143 loci and SLC22A4 gene rs2073838 and rs272893 loci were detected in the two groups. RESULTS: Statistically significant differences were identified in the genotype distributions of SLC22A1 gene rs628031 and rs2282143 loci between the two groups (p < 0.05). The A allele frequency of SLC22A1 gene rs628031 locus and the T allele frequency of rs2282143 locus were higher in the research group than in the control group (p < 0.05). The genotype distributions of rs272893 locus showed a significant difference between the two groups (p < 0.05), but not SLC22A4 gene rs2073838 locus (p > 0.05). CONCLUSIONS: The polymorphisms of SLC22A1 gene rs628031 and rs2282143 loci and SLC22A4 gene rs272893 locus of patients with type 2 diabetes indicated a significant difference between the two groups, suggesting that these genetic locus mutations increase the risk of type 2 diabetes in Chinese Han patients.

Selective scattering polymer dispersed liquid crystal film for light enhancement of organic light emitting diode.

We developed a novel light enhancing film for an organic light emitting diode (OLED) based on polymer dispersed liquid crystal (PDLC). In the film, the liquid crystal droplets are unidirectionally aligned along the film normal direction and exhibit selective scattering. The film scatters light emitted only in directions with large incident angles but not light emitted in directions with small incident angles. When the light is scattered, it changes propagation direction and exits the OLED. The PDLC film reduces the total internal reflection and thus can significantly increase the light efficiency of the OLED.

Flexoelectric in-plane switching (IPS) mode with ultra-high-transmittance, low-voltage, low-frequency, and a flicker-free image.

The demands for a power-saving mode for displaying static images are ubiquitous not only in portable devices but also in price tags and advertising panels. At a low-frequency driving in liquid crystal displays (LCDs) for low-power consumption, the flexoelectric effect arises even in calamitic liquid crystals and the optical appearance of this physical phenomenon is found to be unusually large, being noticed as an image-flickering. Although the inherent integrated optical transmittance of in-plane switching (IPS) mode is relatively lower than that of fringe-field switching (FFS) mode, the IPS mode shows no static image-flickering but an optical spike (the so-called optical bounce), at the transient moment between signal positive and negative frames. Here, we demonstrate an IPS mode using negative dielectric anisotropy of liquid crystals (Δε < 0) and fine-patterned electrodes (the width w of and the space l between electrodes ≤ 3 µm) with reduced operation voltage (up to 40.7% to a conventional FFS mode with Δε < 0), reduced optical bounce (up to 4.4%. to a conventional FFS mode with Δε < 0) and enhanced transmittance (up to 32.1% to a conventional IPS mode with Δε > 0). We believe the result will contribute not only to the scientific understanding of the optical appearance of flexoelectric effect but also pave the way for engineering of a superior low-power consumption LCD.

Full color waveguide liquid crystal display.

We developed a waveguide liquid crystal display from a liquid crystal (LC)/polymer composite. It does not need polarizers or color filters. It is illuminated by color LEDs installed on its edge. The light produced by the edge LEDs is coupled into the display and then waveguided through the display. When the LC is in the transparent state, the incident light is waveguided through and no light comes out of the viewing side of the display. When the LC is in the scattering state, the incident light is scattered and comes out of the display. It can be used either for transparent display or for direct view display. The composite has a submillisecond response time, and a field sequential scheme can be used to display full color images. Because the display does not need polarizers or color filters, its energy efficiency is much higher than current liquid crystal displays.

Stabilized electrically induced Helfrich deformation and enhanced color tuning in cholesteric liquid crystals.

When subjected to an AC electric field perpendicular to its layers, the cholesteric planar state may undergo a periodic layer undulation, known as the Helfrich deformation, which generates a color change of the reflected light. The Helfrich deformation of regular cholesteric liquid crystals is, however, unstable and easily taken over by the focal conic state, and thus the color tuning range is narrow. We demonstrated that the Helfrich deformation can be stabilized in a large electric field region by doping a bent dimer with an anomalously small bend elastic constant and dispersing a small amount of polymer network. By varying the dimer concentration, we were able to systematically change the bend elastic constant and thus verify the theoretical prediction of the undulation threshold electric field and periodicity. We also achieved reflectance tuning with electric field less than 2 V µm-1 and color tuning covering the entire visible light region with electric field as low as 4 V µm-1.

HOXA13 is associated with unfavorable survival and acts as a novel oncogene in prostate carcinoma.

AIM: To investigate the clinical relevance and functional role of HOXA13 in prostate cancer Methods: PCR, western blot and immunohistochemistry were performed to determine the expression. Kaplan-Meier and Cox regression survival analyses investigated the clinical relevance. Cell viability, flow cytometry and transwell assays were used to determine the functional roles. RESULTS: HOXA13 expression is sharply increased in carcinoma tissues and is significantly associated with poor prognosis of prostate cancer patients. Interestingly, nucleus not cytoplasm HOXA13 expression is associated with unfavorable survival of the patients. Furthermore, nucleus HOXA13 expression represents an unfavorable and independent prognosis factor of histological grade 2 or Gleason grade <8 patients. Functionally, forced expression of HOXA13 obviously promotes tumor cell proliferation, migration and invasion, whereas inhibits tumor cell apoptosis. CONCLUSION: HOXA13 is an unfavorable prognostic factor and a novel oncogene for prostate cancer.

Field-symmetrization to solve luminance deviation between frames in a low-frequency-driven fringe-field switching liquid crystal cell.

The development of low-frequency-driven liquid crystal displays (LCDs) has recently received intense attention to open up low-power consumption display devices, such as portable displays, advertising panels and price tags. In fringe-field switching (FFS) LCD mode, a unidirectional electric field gives rise to head-tail symmetry breaking in liquid crystals, so that the flexoelectric effect, a coupling between the elastic distortion and the electric polarization, becomes enormously significant. The effect is thus linked to an unusual optical effect, which badly damages the quality of images by image-flickering, and this image-flickering is mainly caused by transmittance difference between the applied signal frames. Here, we intensively investigate the mechanism of the transmittance deviation, and propose an essential and promising approach to solve the poor image-quality, that is, symmetrization of electric fields between the frames. The result of our work clearly demonstrates that the field-symmetry is crucial to reduce the image-flickering, and it can be obtained by optimization of the thickness of an insulation layer with respect to the ratio of the space between electrodes to the electrode width.

Single-cell gap polymer-stabilized fringe-field switching transflective liquid crystal display.

Transflective liquid crystal displays are highly desired for mobile devices because they can be operated either in transmissive mode, illuminated by backlight in dark ambient light conditions, or reflective mode, illuminated by ambient light in bright ambient light conditions. We developed a single-cell gap transflective display based on fringe-field switching. The display consists of transmissive and reflective subpixels whose operations are synchronized through polymer stabilization. This display has a high contrast ratio because the transmittance-voltage dependences of the two subpixels are similar (they are both in dark state at 0 V and in bright state at an applied voltage) and do not interfere with each other. It has the advantages of single-cell gap and no in-cell retarder and its manufacturing process is simple.

Matched elastic constants for a perfect helical planar state and a fast switching time in chiral nematic liquid crystals.

Chiral nematic liquid crystals possess a self-assembled helical structure and exhibit unique selective reflection in visible and infrared light regions. Their optical properties can be electrically tuned. The tuning involves the unwinding and restoring of the helical structure. We carried out an experimental study on the mechanism of the restoration of the helical structure. We constructed chiral nematic liquid crystals with variable elastic constants by doping bent-dimers and studied their impact on the restoration. With matched twist and bend elastic constants, the helical structure can be restored dramatically fast from the field-induced homeotropic state. Furthermore, defects can be eliminated to produce a perfect planar state which exhibits high selective reflection.

[Efficacy and safety of Yimusake Tablets plus dapoxetine hydrochloride in the treatment of premature ejaculation].

OBJECTIVE: To evaluate the effect and safety of Yimusake Tablets combined with dapoxetine hydrochloride and either of them used alone in the treatment of premature ejaculation (PE). METHODS: We randomly assigned 180 PE patients to oral medication of Yimusake Tablets at 1.5 g per night (group A), dapoxetine hydrochloride at 30 mg at 1－3 hours before anticipated sexual activity (group B), the Yimusake Tablets plus dapoxetine hydrochloride simultaneously (group C), all for 8 weeks. After 4 and 8 weeks of medication, we recorded and compared the changes in the intravaginal ejaculation latency time (IELT), measures of the PE profile (PEP), and adverse events among the three groups of patients. RESULTS: The treatment was accomplished and complete data obtained from 154 of the patients, 56 in group A, 52 in group B, and 46 in group C. After 4 and 8 weeks of medication, the mean IELT was dramatically prolonged in all the three groups as compared with the baseline (P<0.01), most significantly at 8 weeks in group C (ï¼»2.08±0.68ï¼½ min), followed by B (ï¼»1.76±0.52ï¼½ min) and A (ï¼»1.47±0.44ï¼½ min), with statistically significant differences among the three groups (P<0.01). The PEP measures were remarkably improved in group A at 8 weeks (P<0.05), and both in B and C at 4 and 8 weeks (P<0.05), most significantly at 8 weeks in group C (P<0.05), in which the patients scored 1.96±0.77 in perception of control over ejaculation, 2.62±0.98 in satisfaction with sexual intercourse, 3.04±0.62 in PE-related distress, and 3.57±0.80 in PE-induced difficult relationship with their partners, all markedly improved as compared with groups A and B (P<0.05). Adverse reactions were observed in 2 cases (3.6%) in group A, 6 cases (9.6%) in B, and 5 cases (10.9%) in C. No severe adverse events occurred in any of the patients during the study. CONCLUSIONS: Combined medication of Yimusake Tablets and dapoxetine hydrochloride, with its advantages of effectiveness and safety, deserves to be recommended for the treatment of PE.

Light-Driven Reversible Alignment Switching of Liquid Crystals Enabled by Azo Thiol Grafted Gold Nanoparticles.

Stimuli-directed alignment control of liquid crystals (LCs) with desired molecular orientation is currently in the limelight for the development of smart functional materials and devices. Here, photoresponsive azo thiol (AzoSH) was grafted onto gold nanoparticles (GNPs). The resulting hybrid GNPs were able to homogeneously mix with a commercially available nematic LC host, as evidenced by Cryo-TEM. Interestingly, the LC nanocomposites were found to undergo reversible alignment transition upon light irradiation as a consequence of the trans-cis photoisomerization of the azo groups on the GNP surface. LC molecules in either planar or bare glass cells were able to change their alignment to vertical upon UV irradiation, while the vertically aligned LC molecules returned to the planar or random orientation under visible irradiation. Neither the azo thiol molecules nor the unfunctionalized GNPs alone promoted the alignment of the LC molecules in the system upon light irradiation. The photoinduced vertical alignment without applied electric or magnetic field was very stable over time and with respect to temperature. Furthermore, an optically switchable device based on the photostimulated reversible alignment control of LCs was demonstrated.

Mechanism of electrically induced photonic band gap broadening in polymer stabilized cholesteric liquid crystals with negative dielectric anisotropies.

We experimentally observed that the photonic band gap (reflection band) of polymer stabilized cholesteric liquid crystals with negative dielectric anisotropies can be greatly broadened under DC electric fields. We explored the underlying mechanism. We found that the dispersed polymer network moved when DC voltages were applied across the liquid crystal cell. The motion of the polymer network stretched the helical pitch of the liquid crystal on one side of the cell and compressed the helical pitch on the other side of the cell. We proposed a phenomenological theory to explain the motion of the polymer network and the effect of the polymer network on the helical pitch, and this theoretical prediction agreed well with the experimental results.

Light-directing omnidirectional circularly polarized reflection from liquid-crystal droplets.

Constructing and tuning self-organized three-dimensional (3D) superstructures with tailored functionality is crucial in the nanofabrication of smart molecular devices. Herein we fabricate a self-organized, phototunable 3D photonic superstructure from monodisperse droplets of one-dimensional cholesteric liquid crystal (CLC) containing a photosensitive chiral molecular switch with high helical twisting power. The droplets are obtained by a glass capillary microfluidic technique by dispersing into PVA solution that facilitates planar anchoring of the liquid-crystal molecules at the droplet surface, as confirmed by the observation of normal incidence selective circular polarized reflection in all directions from the core of individual droplet. Photoirradiation of the droplets furnishes dynamic reflection colors without thermal relaxation, whose wavelength can be tuned reversibly by variation of the irradiation time. The results provided clear evidence on the phototunable reflection in all directions.

Programmable Dynamic Information Storage Composite Film with Highly Sensitive Thermochromism and Gradually Adjustable Fluorescence.

The development of an integrated material system capable of effectively organizing and combining multisource information, such as dynamic pigmentary, structural, and fluorescent colors, is significant and challenging. Achieving such programmable dynamic information storage can considerably enhance the diversity and security of information deliveries. Here, a polymer-stabilized cholesteric liquid crystal system with highly temperature-sensitive structural color and light-sensitive pigmentary and fluorescence colors is presented. The prepared cholesteric liquid crystals (clcs) can reversibly change their structural color from red to blue within variational 3 °C near room temperature, and exhibit a gradually adjustable fluorescence which can transform from blue to pink and finally to bright red. All this dynamic information is programmable and tailored, hundreds of thousands of (>540 000) pattern combinations can easily be achieved by optical writing with a "bagua" pattern photomask. Therefore, if the corresponding code combinations to the pattern are assigned particular meanings, encrypted transmission of information with very high security can be achieved by utilizing applicable information encoding tables and decryption rules.

Hsa_circ_0014784-induced YAP1 promoted the progression of pancreatic cancer by sponging miR-214-3p.

BACKGROUND: Pancreatic cancer (PC) is one of the most common gastrointestinal tumors globally. Former investigations discovered that circular RNAs (circRNAs) play an important role in PC development. circRNAs belong to a new class of endogenous noncoding RNAs, which have been found to mediate the progression of diverse types of tumors. Nevertheless, the roles of circRNAs and the underlying regulatory mechanisms in PC remain unknown. METHODS: In this study, our team employed next-generation sequencing (NGS) to examine the abnormal circRNA expression in PC tissues. The circRNA expression in PC cell lines and tissues was detected. Then, regulatory mechanism and targets were examined with bioinformatics analysis, luciferase reporting analysis, Transwell migration, 5-ethynyl-2'-deoxyuridine, and CCK-8 analysis. An in vivo experiment was employed to elucidate hsa_circ_0014784 roles in PC tumor growth and metastasis. RESULTS: The results showcased abnormal circRNA expression in PC tissues. Our lab also found that hsa_circ_0014784 expression incremented in PC tissues and cell lines, implying that hsa_circ_0014784 functioned in PC progression. hsa_circ_0014784 downregulation inhibited PC proliferation and invasion in vivo and in vitro. The bioinformatics and luciferase report data validated that both miR-214-3p and YAP1 were hsa_circ_0014784 binding partners. The overexpression of YAP1 reversed the migration, proliferation, and epithelial - mesenchymal transition (EMT) of PC cells and the angiogenic differentiation of HUVECs after miR-214-3p overexpression. CONCLUSION: Taken together, our study found that hsa_circ_0014784 downregulation decremented invasion, proliferation, EMT, and angiogenesis of PC by regulating miR-214-3p/YAP1 signaling.