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Triple-negative breast cancer (TNBC) has an aggressive phenotype and poor prognosis due to the lack of specific targeted treatments. The development of an effective therapeutic strategy with a novel mechanism is essential for TNBC management. Olaparib, a PARP inhibitor, has been approved for the treatment of breast or ovarian cancer patients with breast cancer gene 1/2 (BRCA1/2) mutations. Here, we report the development of a small molecule targeting PARP1 based on the hydrophobic tagging (HyT) method. Targeted protein misfolding and consequent degradation are caused by HyT. Hydrophobic-tagged olaparib induces the proteasome-dependent degradation of PARP1 and shows enhanced antitumor effects compared to olaparib in TNBC cells. In addition, hydrophobic-tagged olaparib causes ER stress-related unfolded protein response (UPR), autophagy, and apoptosis. These results point towards encouraging prospects for chemically modifying approved drugs that not only exhibit superior effects compared to those of the original drugs by triggering novel mechanisms but also provide great feasibility in the translational scenario.

A biomimetic multifunctional nanocomposite was synthesized, in which a polydopamine (PDA) thin film was deposited on a layered double hydroxide (LDH) through an interlayer polymerization. Kinetic controlled polymerization of dopamine (DA) in a basic buffer solution under a nitrogen atmosphere provided a synthetic pathway for the nanostructured PDA/LDH composites without polymer agglomerates, allowing the crystallinity of the pristine LDH nanoparticles to be maintained. The contraction of the interlayer spacing for the (00l) reflection of PDA/LDH nanocomposites demonstrated intercalation of PDA into the LDH interlayer space. The catalytic activity of the PDA/LDH nanocomposites was evaluated by observing the reduction of p-nitrophenol in the presence of NaBH4, in which the PDA layer acts as a protection layer against surface contamination of the nanocomposites. Electrochemical capacitive performance was also observed due to the strong adhesion of PDA to the Ni foam electrode. The nanostructure of the PDA/LDH nanocomposites induced by interlayer polymerization drove the incorporative organic–inorganic functional materials with blocked surfaces and improved the electrochemical properties, providing a reliable synthetic pathway to prepare multifunctional nanohybrid materials.

Glaucoma is one of the leading causes of preventable blindness, affecting > 2 million people in the United States. Recently, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitors were found to exert preventive effects against glaucoma. However, there is no evidence for the role of 11β-HSD1 inhibitors against glaucoma. Here, we developed a novel 11β-HSD1 inhibitor, (1R,2S,3S,5R,6S,7S)-6-(2-(6-(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-methyl-1,1-dioxido-1,2,6-thiadiazinan-2-yl)acetamido)-adamantane-2-carboxamide (KR-67607) and showed its protective effects against ischemia-reperfusion-induced eye injury. We demonstrate that KR-67607 effectively reduced cortisol levels in mouse eyes and maintained the trabecular meshwork (TM) structure in the presence of transient ischemic stress. Furthermore, KR-67607 reversed the elevation of intra-ocular pressure (IOP), suggesting that the TM structure maintained by KR-67607 prevented the excessive rise in IOP that exacerbates glaucoma. KR-67607 was shown to have a higher specificity for 11β-HSD1 than carbenoxolone (CBX) in vitro. Moreover, KR-67607 reduced apoptosis and the structural disruption of TM cells. Antioxidation was the major protective pathway of KR-67607 against chemically-induced ischemia-reperfusion in TM cells and the glucocorticoid receptor (GR) was closely associated with this pathway. When TM cells undergo ischemic stress, GR is activated and then translocates to the cell nucleus where it interferes with Nrf-2-mediated antioxidant gene expression. However, when KR-67607 inhibited GR translocation, Nrf-2 was able to induce antioxidant gene transcription, which consequently, enhanced the antioxidant capacity of the cells. In conclusion, our current work describes a novel selective 11β-HSD1 inhibitor for glaucoma treatment and provides evidence of its physiological role in anti-oxidative pathways in the TM.

Interpenetration is known for the structures of many minerals and ice; most notably for ice, it exists in doubly interpenetrating (VI, VII, and VIII) and non-interpenetrating (Ih) forms with the latter being porous and having nearly half of the density of the former. In synthetic materials, specifically in metal–organic frameworks (MOFs), interpenetration is generally considered undesirable because it reduces porosity. However, on the contrary, many advantageous properties also arise when MOFs are interpenetrated, such as selective guest capture, stepwise gas adsorption, enhanced framework robustness, photoluminescence control, and guest-responsive porosity. Therefore, various strategies have been suggested to control interpenetration during synthesis. However, once these extended network materials are prepared as interpenetrating or non-interpenetrating structures, the degree of interpenetration generally remains unchanged, because numerous chemical bonds must be broken and subsequently reformed in a very concerted way during the process unlike some interlocked coordination compounds in solution (Figure 1a).

Polymerized melanin thin films were electrochemically synthesized in a 5,6-dihydroxyindole precursor solution on indium tin oxide (ITO) substrates using the cyclic voltammetry and constant potential methods. Tris(hydroxymethyl)aminomethane (THAM) and phosphate buffer solutions were applied to prepare the films that were well deposited to the ITO substrates. The films that were synthesized in the THAM buffer solution exhibited a faster growth rate and better adhesion to the ITO electrodes than the films in the phosphate buffer. The film thickness linearly increased at the growth rate of 0.8 nm/s as the deposition time and number of cycles increased. Two electrochemical conditions produced similar thicknesses as well as physical properties in each buffer solution. However, the constant potential method demonstrated that this provides the synthetic advantages of faster deposition and less consumption of electric charge compared to the cyclic voltammetry route.

A dip-coating technique was used to deposit self-assembled monolayer arrays of PMMA colloidal particles with a diameter of 125 nm onto a silicon surface coated with (3-aminopropyl)-triethoxysilane (APTES), exploiting the electrostatic interaction between the negative particle and the positive substrate. The PMMA colloidal arrangement was controlled efficiently by the dipping time and temperature, concentration and pH of the colloidal solutions. A non-close-packed monolayer assembly was prepared without the need for pre-patterned templates. The deposition of platinum metal on the 2D PMMA arrays and subsequent thermal treatment produced ordered hemispherical Pt nanoshells, 74 nm in height, as soft-lithographic templates and biological sensor materials.

Monolayer assemblies of zeolite microcrystals, polymer nanobeads and caged proteins were successfully applied to a highly ordered MgAl-LDH monolayer by using the electrostatic attractions between the negatively charged particles and positively charged MgAl-LDH without chemical modifications. Ultrasonication leads to the monolayer assembly of ZSM-5 microcrystals with a maximum preferred contact over the MgAl-LDH monolayer, where the ZSM-5 microcrystals are oriented in the (0k0) crystallographic direction. PMMA and ferritin were also adsorbed on the monolayer LDH nanocrystal surface through self-assembly in solution. Homogeneous PMMA colloids-LDH composite layers on Si were successfully prepared, thanks to the improved interfacial compatibility between the immobilized LDH and polymer surface charges. Thermal treatment at 150 °C resulted in the formation of continuous polymer coatings over the LDH/Si monolayer. The mixing of colloidal solutions of LDH and PMMA led to the formation of bulk-type polymer-LDH composites after the melting of the polymer phase, where the polymer was homogeneously coated over the LDH crystals without the phase segregation of the LDH nanocrystals. The charged hydroxide layers of the LDH nanocrystals provided the multi-functional interface characteristics required to assemble the functional particles, resulting in the binary hybrid structures of inorganic-inorganic, polymer-inorganic or bio-inorganic composites. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The mercury(II) complexes of 5-pyridin-2-yl-5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiin-2-thione (2PyEDT-DTT: 1), [Hg(2PyEDT-DTT)X2] (X=Cl (2a), Br (2b) and I (2c)) were obtained from the reaction of HgX2 and 2PyEDT-DTT. These complexes adopt a dimeric arrangement of [Hg(2PyEDT-DTT)X2]2 through intermolecular Hg⋯N and Hg⋯S interactions. According to the FT-IR/UV–Vis/NMR spectroscopy data, these intermolecular interactions are cleaved in media containing trace H2O. [Hg(2PyDT-DTT)2] (3; 2PyDT-DTT: 5-(1-pyridin-2-yl-vinylsulfanyl)-2-thioxo-[1,3]dithiole-4-thiolate) was isolated from the filtrate of 2. The Hg(II) ion is located in a center of symmetry and adopts a distorted octahedral geometry with four sulfur atoms (two from the thiolate groups and two from the sulfide groups) and two nitrogen atoms from the pyridyl group. The time-dependent solution UV–Vis and 1H NMR measurements showed the transformation of 2PyDT-DTT to 2PyEDT-DTT caused by trace H2O in organic solvents.

Microscopic images of single crystalline PEN derivatives; (a) commercial PEN chemicals, (b) PEN-V crystal grown on vapor phase (14 days), (c) PEN-V crystal grown on vapor phase (30 days), (d)PQ-S crystal obtained from a saturated solution of PEN, (e) commer-cial PQ chemicals and (f) PQ-V crystal grown on vapor phase (30 days).

o C for 1 h. A solution of OTS in anhydrous hexane (10 mM) was used as an "ink" and applied to the stamp using a spinner at 3000 rpm for 30 s. The inked stamp was placed in contact with Si and held in place for 30 seconds, yielding OTS thin films with approximately 30 A mass coverage. 10 Fe(NO3)3·9H2O and FeCl3·6H2O were used as starting ma- terials to produce hematite and akaganeite, respectively. The hematite thin films were deposited from a 0.05 M iron nitrate solution. The akaganeite thin film was deposited from 0.05 M iron chloride in 0.1 M acetate buffer solution. The OTS-pat- terned Si substrates were immersed in the solution for 2 h at 75 o C with constant stirring. The final pH range of the iron nitrate and iron chloride-acetate buffer solutions was 1.5 ~ 1.7 and 2.5 ~ 3.0, respectively. The color of the nitrate and chloride solutions was red-brown and light ochre, respectively. Both precipitates and thin films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Figure 1(a) and (c) show SEM images of the precipitates and thin film prepared in Fe(NO3)3 solution. The deposited thin film was densely covered with hematite nanoparticles with spherical shapes with an average size of 20 - 50 nm. XRD of both the powder and film showed three predominant peaks at 33.2, 35.6, 65.4° 2θ, which were assigned to (104), (110) and (214) for the hematite phase.

The efficient electron injection by direct dye-to-TiO(2) charge transfer and strong adhesion of mussel-inspired synthetic polydopamine (PDA) dyes with TiO(2) electrode is demonstrated. Spontaneous self-polymerization of dopamine using dip-coating (DC) and cyclic voltammetry (CV) in basic buffer solution were applied to TiO(2) layers under a nitrogen atmosphere, which offers a facile and reliable synthetic pathway to make the PDA dyes, PDA-DC and PDA-CV, with conformal surface and perform an efficient dye-to-TiO(2) charge transfer. Both synthetic methods led to excellent photovoltaic results and the PDA-DC dye exhibited larger current density and efficiency values than those in the PDA-CV dye. Under simulated AM 1.5 G solar light (100 mW cm(-2)), a PDA-DC dye exhibited a short circuit current density of 5.50 mW cm(-2), corresponding to an overall power conversion efficiency of 1.2 %, which is almost 10 times that of the dopamine dye-sensitized solar cell. The PDA dyes showed strong adhesion with the nanocrystalline TiO(2) electrodes and the interface engineering of a dye-adsorbed TiO(2) surface through the control of the coating methods, reaction times and solution concentration maximized the overall conversion efficiency, resulting in a remarkably high efficiency.

We report herein a reliable method of fabricating 2D periodic gold nanopillars with well-defined anisotropic shapes by the combinational actions of colloidal crystals and gold evaporation. The deposition of gold on a polymer template produced dual functional Janus-like nanopillars up to 633 nm in height as well as hemispherical shells with 120 nm. The thermal-induced active migration of the nanopillars from the pristine position in the lateral direction occurred at the colloidal defects while some cavity space was formed inside the gold pillars. The nano-structured gold pillars exhibited a strong surface plasmon resonance at 598 nm, as compared to that of the solid gold nanospheres at 520 nm, and a noticeable red shift to 640 nm was induced by the removal of the polymer template.

This paper presents facile, reproducible soft-lithographic technique for fabricating textured crystalline silicon solar cell with hexagonally close-packed hemispherical arrays using ordered polymeric microspheres. Close-packed monolayers of polymer microspheres were deposited on flat cleaned glass substrate using spin-casting technique. The relief structure of highly ordered microspheres successfully generated their negative replica of elastomers. Hemispherical microlens arrays were molded by dispensing and curing liquid ultraviolet-curable photopolymers into the negative replica on crystalline silicon solar cell module. Sub-micrometer scaled microlens with uniform, cleaned surface morphology were easily reproduced by using the prepared molds, without multi-step engineering processes. The microlens-coated crystalline silicon solar cell showed additional increment of 1% in solar cell efficiency, compared to that of SiNx anti-reflection coated one, as well as remarkable decrease of reflectance in SiNx-uncoated solar cell.

This paper describes a facile, reproducible soft-lithography-based method for fabricating hexagonally close-packed microlens arrays by templating the surface of a colloidal monolayer, which is formed by spin-casting monodisperse polystyrene microspheres. The relief structure of colloidal monolayers has successfully generated PDMS elastomers with hexagonal arrays of hemispherical air voids. Closely packed hemispherical microlens arrays were imprinted on ultraviolet-curable photopolymers which are bound on glass substrates. Atomic force microscopy measurements showed that each spherical hole of the PDMS molds is 103 nm deep and the replicated microlens is 95 nm in height with narrow size distribution and good reproducibility. Without a multistep engineering process, this method might provide a reliable route to fabricate embossed thin layers ranging from nanometer to micrometers by controlling the size of polymer microspheres over a centimeter scale area.

The assembly of Rh(CO)(2)Cl(amine) via molecular orbital symmetry interactions, resulting in the formation of one-dimensional molecular wires, has been discovered. The assembly behavior was quite dependent on the type of amine. The interchain distances and optical properties could be controlled by changing the length of the alkyl chain in the amine. We believe that this discovery can be applied not only to preparing more diverse one-dimensional molecular wires via the introduction of predesigned amines but also to gaining a deeper understanding of the physical properties of molecular metals.

Ni nanoparticles embedded in the pores of a mesoporous MOF (MesMOF-1) act as a catalyst for hydrogenolysis of nitrobenzene or hydrogenation of styrene.

The cover picture shows a wide range of hybrid assemblies; caged proteins (nanometer), polymer beads (hundreds nm) and zeolite crystals (micrometer scale) are self-assembled onto highly ordered monolayers of layered double hydroxide (LDH) nanocrystals by the electrostatic attraction between the negatively charged particles and the positively charged LDH surface. The various composite materials of polymer beads and LDH nanocrystals are also discussed in the article by D.-Y. Jung et al. on p. 5573 ff.