[Role of TGF-ß/Smad signaling pathway in diabetic kidney disease and research progress of traditional Chinese medicine intervention].

Diabetic kidney disease is an important microvascular complication of diabetes and the leading cause of end-stage renal disease. Its pathological characteristics mainly include epithelial mesenchymal transition(EMT) in glomerulus, podocyte apoptosis and autophagy, and damage of glomerular filtration barrier. Transforming growth factor-ß(TGF-ß)/Smad signaling pathway is specifically regulated by a variety of mechanisms, and is a classic pathway involved in physiological activities such as apoptosis, proliferation and differentiation. At present, many studies have found that TGF-ß/Smad signaling pathway plays a key role in the pathogenesis of diabetic kidney disease. Traditional Chinese medicine has significant advantages in the treatment of diabetic kidney disease for its multi-component, multi-target and multi-pathway characteristics, and some traditional Chinese medicine extracts, traditional Chinese medicines and traditional Chinese medicine compound prescription improve the renal injury of diabetic kidney disease by regulating TGF-ß/Smad signaling pathway. This study clarified the mechanism of TGF-ß/Smad signaling pathway in diabetic kidney disease by expounding the relationship between the key targets of the pathway and diabetic kidney disease, and summarized the research progress of traditional Chinese medicine in the treatment of diabetic kidney disease by interfering with TGF-ß/Smad signaling pathway in recent years, to provide reference for drug research and clinical treatment of diabetic kidney disease in the future.

Waterproof Narrow-Band Fluoride Red Phosphor K2TiF6:Mn4+ via Facile Superhydrophobic Surface Modification.

With unique and efficient narrow-band red emission and broadband blue light absorption characteristics, Mn4+-activated fluoride red phosphors have gained increasing attention in warm white LEDs (WLEDs) and liquid crystal display (LCD) backlighting applications, whereas the intrinsic hygroscopic nature of these phosphors have inevitably limited their practical applications. Herein, a waterproof narrow-band fluoride phosphor K2TiF6:Mn4+ (KTF) has been demonstrated via a facile superhydrophobic surface-modification strategy. With the use of superhydrophobic surface modification with octadecyltrimethoxysilane (ODTMS) on KTF surfaces, the moisture-resistance performance and thermal stability of the phosphor KTF can be significantly improved. Meanwhile, the absorption, and quantum efficiency did not show obvious changes. The surface-modification processes and mechanism, as well as moisture-resistance performances and luminescence properties, of the phosphors have been carefully investigated. It was found that the luminous efficiency (LE) of the modified KTF was maintained at 83.9% or 84.3% after being dispersed in water for 2 h or aged at high temperature (85 °C) and high humidity (85%) atmosphere (HTHH) for 240 h, respectively. The WLEDs fabricated with modified KTF phosphor showed excellent color rendition with lower color temperature (2736 K), higher color rendering index (CRI, Ra = 87.3, R9 = 80.6), and high luminous efficiency (LE = 100.6 lm/W) at 300 mA. These results indicate that hydrophobic silane coupling agent (SCA) surface modification was a promising strategy for enhancing moisture resistance of humidity-sensitive phosphors, exhibiting great potential for practical applications.

Confining the polymerization degree of graphitic carbon nitride in porous zeolite-Y and its luminescence.

Graphitic carbon nitride (g-C3N4) has aroused broad interest in the field of photocatalysis and luminescence as a kind of metal-free semiconductor with a suitable band gap of ∼2.7 eV. The properties largely depend on the polymerization degree of g-C3N4. This research exploits the nanocages of zeolite-Y to confine the polymerization of the melamine monomer to form g-C3N4. The composites are achieved via a facile two-step method, i.e., melamine-Na+ ion exchange reaction in the cage of the zeolite and subsequent calcination. BET measurement and transmission electron microscopy (TEM) confirm that the g-C3N4 is encapsulated in zeolite-Y, and the polymerization degree can be controlled by the melamine contents exchanged with Na+ in the cages of zeolite-Y. Photoluminescence and vibration spectroscopy also show the features of g-C3N4 with different polymerization degrees in the zeolite-Y composites. This research gives a perspective of fabricating subnanoscale g-C3N4 in porous zeolite, which may find potential applications in photocatalysis and optoelectronics.

Confining Mn2+-Doped Lead Halide Perovskite in Zeolite-Y as Ultrastable Orange-Red Phosphor Composites for White Light-Emitting Diodes.

CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) have emerged as competitive candidate luminescent materials in the photoelectric fields due to their superior luminescence properties. However, the major drawback such as poor resistance to temperature, moisture, and irradiation of light, especially for the red QDs with I-, hinders their practical applications. Herein, we synthesized Mn2+-doped CsPbCl3 embedded in the cage of zeolite-Y as a new orange-red phosphor for the white light-emitting diode (WLED). The composites have significantly improved resistance to both elevated temperature and water over the bare Mn2+-doped QDs. The former exhibits little degradation whereas the latter shows apparent decline upon the irradiation of lights in the orange LED devices, which are fabricated by employing each material as a color-conversion phosphor coated on a 365 nm UV chip. A WLED is also achieved with a 365 nm UV chip coated with a CsPb(Cl0.5,Br0.5)3-Y blue phosphor and a CsPb0.75Mn0.25Cl3-Y orange phosphor. The device possesses a Commission Internationale de l'Éclairage coordinate of (0.34, 0.36), a correlated color temperature of 5336 K and a color rendering index of 81.

Transition Metal-Involved Photon Upconversion.

Upconversion (UC) luminescence of lanthanide ions (Ln3+) has been extensively investigated for several decades and is a constant research hotspot owing to its fundamental significance and widespread applications. In contrast to the multiple and fixed UC emissions of Ln3+, transition metal (TM) ions, e.g., Mn2+, usually possess a single broadband emission due to its 3d5 electronic configuration. Wavelength-tuneable single UC emission can be achieved in some TM ion-activated systems ascribed to the susceptibility of d electrons to the chemical environment, which is appealing in molecular sensing and lighting. Moreover, the UC emissions of Ln3+ can be modulated by TM ions (specifically d-block element ions with unfilled d orbitals), which benefits from the specific metastable energy levels of Ln3+ owing to the well-shielded 4f electrons and tuneable energy levels of the TM ions. The electric versatility of d0 ion-containing hosts (d0 normally viewed as charged anion groups, such as MoO66- and TiO44-) may also have a strong influence on the electric dipole transition of Ln3+, resulting in multifunctional properties of modulated UC emission and electrical behaviour, such as ferroelectricity and oxide-ion conductivity. This review focuses on recent advances in the room temperature (RT) UC of TM ions, the UC of Ln3+ tuned by TM or d0 ions, and the UC of d0 ion-centred groups, as well as their potential applications in bioimaging, solar cells and multifunctional devices.

Gelatin-siloxane nanoparticles to deliver nitric oxide for vascular cell regulation: synthesis, cytocompatibility, and cellular responses.

Nitric oxide (NO) is an important mediator in cardiovascular system to regulate vascular tone and maintain tissue homeostasis. Its role in vascular cell regulation makes it promising to address the post-surgery restenosis problem. However, the application of NO is constrained by its high reactivity. Here, we developed a novel NO-releasing gelatin-siloxane nanoparticle (GS-NO NP) to deliver NO effectively for vascular cell regulation. Results showed that gelatin-siloxane nanoparticles (GS NPs) could be synthesized via sol-gel chemistry with a diameter of ∼200 nm. It could be modified into GS-NO NPs via S-nitrosothiol (RSNO) modification. The synthesized GS-NO NPs could release a total of ∼0.12 µmol/mg NO sustainably for 7 days following a first-order exponential profile. They showed not only excellent cytocompatibility, but also rapid intracellularization within 2 h. GS-NO NPs showed inhibition of human aortic smooth muscle cell (AoSMC) proliferation and promotion of human umbilical vein endothelial cell (HUVEC) proliferation in a dose-dependent manner, which is an important approach to prevent restenosis. With GS-NO NP dose at 100 µg/mL, the proliferation of AoSMCs could be slowed down whereas the growth of HUVECs was significantly promoted. We concluded that GS-NO NPs could have potential to be used as a promising nano-system to deliver NO for vascular cell regulation.

Biomimetic three-dimensional anisotropic geometries by uniaxial stretching of poly(ε-caprolactone) films: degradation and mesenchymal stem cell responses.

Geometric cues have been used for a variety of cell regulation and tissue regenerative applications. While the function of geometric cues is being recognized, their stability and degradation behaviors are not well known. Here, we studied the influence of degradation on uniaxial-stretch-induced poly(ε-caprolactone) (UX-PCL) ridge/groove arrays and further cellular responses. Results from accelerated hydrolysis in vitro showed that UX-PCL ridge/groove arrays followed a surface-controlled erosion, with an overall geometry remained even at ∼45% film weight loss. Compared to unstretched PCL flat surfaces and/or ridge/groove arrays, UX-PCL ridge/groove arrays achieved an enhanced morphological stability against degradation. Over the degradation period, UX-PCL ridge/groove arrays exhibited an "S-shape" behavior of film weight loss, and retained more stable surface hydrophilicity and higher film mechanical properties than those of unstretched PCL surfaces. Human mesenchymal stem cells (MSCs) aligned better toward UX-PCL ridge/groove arrays when the geometries were remained intact, and became sensitive with gradually declined nucleus alignment and elongation to the geometric degradation of ridges. We speculate that uniaxial stretching confers UX-PCL ridge/groove arrays with enhanced stability against degradation in erosive environment. This study provides insights of how degradation influences geometric cues and further cell responses, and has implications for the design of biomaterials with stability-enhanced geometric cues for long-term tissue regeneration.

Biomimetic three-dimensional anisotropic geometries by uniaxial stretch of poly(ε-caprolactone) films for mesenchymal stem cell proliferation, alignment, and myogenic differentiation.

Anisotropic geometries are critical for eliciting cell alignment to dictate tissue microarchitectures and biological functions. Current fabrication techniques are complex and utilize toxic solvents, hampering their applications for translational research. Here, we present a novel simple, solvent-free, and reproducible method via uniaxial stretching for incorporating anisotropic topographies on bioresorbable films with ambitions to realize stem cell alignment control. Uniaxial stretching of poly(ε-caprolactone) (PCL) films resulted in a three-dimensional micro-ridge/groove topography (inter-ridge-distance: ~6 µm; ridge-length: ~90 µm; ridge-depth: 200-900 nm) with uniform distribution and controllable orientation by the direction of stretch on the whole film surface. When stretch temperature (Ts) and draw ratio (DR) were increased, the inter-ridge-distance was reduced and ridge-length increased. Through modification of hydrolysis, increased surface hydrophilicity was achieved, while maintaining the morphology of PCL ridge/grooves. Upon seeding human mesenchymal stem cells (hMSCs) on uniaxial-stretched PCL (UX-PCL) films, aligned hMSC organization was obtained. Compared to unstretched films, hMSCs on UX-PCL had larger increase in cellular alignment (>85%) and elongation, without indication of cytotoxicity or reduction in cellular proliferation. This aligned hMSC organization was homogenous and stably maintained with controlled orientation along the ridges on the whole UX-PCL surface for over 2 weeks. Moreover, the hMSCs on UX-PCL had a higher level of myogenic genes' expression than that on the unstretched films. We conclude that uniaxial stretching has potential in patterning film topography with anisotropic structures. The UX-PCL in conjunction with hMSCs could be used as "basic units" to create tissue constructs with microscale control of cellular alignment and elongation for tissue engineering applications.