Design and Synthesis of a Fluorescent Reporter of Protein Kinase Activity

There is widespread interest in developing fluorescent reporters of protein kinase activity, species that can furnish a visual readout of both when and where intracellular kinases are activated in response to a stimulus. We have constructed and identified, via a combination of rational design, library synthesis, and screening, a difluorofluorescein-appended peptide-based species that responds to protein kinase C phosphorylation in a fluorescently sensitive fashion. The phosphorylation-induced divalent metal ion-mediated 265% enhancement in fluorescence proceeds with a Vmax of 8.5 μmol/min·mg and a Km of 20.5 μM

Highly Enantioselective Arylation of Aldehydes and Ketones Using AlArEt₂(THF) as Aryl Sources

A series of AlArEt2(THF) (Ar = Ph (1a), 4-MeC6H4 (1b), 4-MeOC6H4 (1c), 4-Me3SiC6H4 (1d), 2-naphthyl (1e)) were synthesized from reactions of AlEt2Br(THF) with ArMgBr. In CDCl3 solution, the 1H NMR spectra showed that AlArEt2(THF) compounds exist as a mixture of four species of formulas of AlArxEt3-x (THF) (x = 0, 1, 2, or 3). AlArEt2(THF) compounds were found to be superior and atom-economic reagents for asymmetric aryl additions to organic carbonyls. Aryl additions of AlArEt2(THF) to aldehydes catalyzed by the titanium(IV) complex of (R)-H8−BINOL were efficient with a short reaction time of 1 h, affording aryl addition products as exclusive or main products in high yields and excellent enantioselectivities of up to 98% ee. Although ethyl additions to aldehydes occurred in minor extent, this study demonstrates that increasing the amount of AlArEt2(THF) from 1.2 to 1.4 or to 1.6 equiv significantly improved the aryl addition products of up to >99%. On the other hand, asymmetric arylations of AlArEt2(THF) to ketones employing a titanium(IV) catalyst of (S)-BINOL produced optically active tertiary alcohols exclusively in excellent enantioselectivities of up to 94% ee

Tuning Perovskite Morphology by Polymer Additive for High Efficiency Solar Cell

Solution processable planar heterojunction perovskite solar cell is a very promising new technology for low cost renewable energy. One of the most common cell structures is FTO/TiO₂/CH₃NH₃PbI_3‑<i>x</i>Cl_<i>x</i>/spiro-OMeTAD/Au. The main issues of this type of solar cell are the poor coverage and morphology control of the perovskite CH₃NH₃PbI_3‑<i>x</i>Cl_<i>x</i> film on TiO₂. For the first time, we demonstrate that the problems can be easily resolved by using a polymer additive in perovskite precursor solution during the film formation process. A 25% increase in power conversion efficiency at a value of 13.2% is achieved by adding 1 wt % of poly­(ethylene glycol) in the perovskite layer using a 150 °C processed TiO₂ nanoparticle layer. The morphology of this new perovskite was carefully studied by SEM, XRD, and AFM. The results reveal that the additive controls the size and aggregation of perovskite crystals and helps the formation of smooth film over TiO₂ completely. Thus, the <i>V</i>_oc and <i>J</i>_sc are greatly increased for a high efficiency solar cell. The amount of additive is optimized at 1 wt % due to its insulating characteristics. This research provides a facile way to fabricate a high efficiency perovskite solar cell by the low temperature solution process (<150 °C), which has the advancement of conserving energy over the traditional high temperature sintering TiO₂ compact layer device

Lung metastatic rate in mice.

Lung metastatic rate in mice.</p

Andrographolide and radiation reduces MMP-2 expression.

Gelatin zymography was performed using the conditioned media that were harvested after 48 hours in the presence or absence of 10 uM andrographolide, and then treated with/without radiation (2 or 4Gy) for 24 hours. The samples were applied without reduction to a 10% polyacrylamide gel containing gelatin, and proteolytic activity was demonstrated by digestion of the gelatin and clearing of the gel.</p

Andrographolide with radiation suppressed angiotensin II-induced MMP-2 expression through inhibition of ERK1/2 signaling.

Cells were incubated with 300 nM Ang II for 1 hour and then treated with andrographolide, irradiation, or both for 24 hours. Protein level was determined by Western blotting.</p

Andrographolide with radiation enhanced downregulation of radiation-induced MMP-2 leading to the suppression of ERK signaling.

The cells were treated with 10 uM andrographolide with/without 2Gy or 4 Gy radiation for 24 hours. The figure displays typical data of MMP-2, phosphor-ERK1/2, total-ERK1/2 and NF-κB activity by Western blotting. Relative band intensities were analyzed by the Image J software. β-actin was used as an internal control for normalization. The numbers beneath the blots indicate the relative expression of each band when compared to the respective untreated control.</p

Andrographolide plus radiation reduced angiotensin II-induced MMP-2 activation and invasion.

The Ras-transformed cells were incubated with/without 300 nM angiotensin II (Ang II) for 1 hour, and then treated with andrographolide, or radiation, or both for 24 hours. (A) The typical data show the gelatin zymography analysis band of the MMP-2 in conditioned media. (B) Invasion assays were performed using Transwell inserts of 8-micron pore size membrane and matrigel. After treatment, the cells were seeded in Transwell plates for 72 hours. The invaded cells were stained and quantified at an optical density of 560 nm. The experiments have been repeated three times; representative results of three independent experiments were shown. Quantification of cell invasion expressed as the percentage of control; one-way ANOVA was used for statistical analysis.</p

Effects of andrographolide and radiation on the expression EMT-related markers (E-cadherin, vimentin) and matrix metalloproteinases MMP-2 and -9.

(A) RAS-transformed cells were treated with 10 uM andrographolide for 6 hours with and without 2 or 4 Gy radiation. After 24 hours, the cells were harvested for preparation of whole-cell protein lysates followed by Western blotting to detect the given proteins. (B) Quantitative analyses of MMP-2 expression evaluated by MMP-2/GAPDH ratio. The results are shown as mean ± SD (n = 3). *p < 0.05 for andrographolide combined with 4 Gy vs. andrographolide alone.</p