A Mild and Efficient Direct α-Amination of β-Dicarbonyl Compounds Using Iodosobenzene and <i>p</i>-Toluenesulfonamide Catalyzed by Perchlorate Zinc Hexahydrate

A direct α-amination of β-dicarbonyl compounds has been achieved by using iodosobenzene (PhIO) as an oxidant and <i>p</i>-toluenesulfonamide (TsNH₂) as an aminating reagent in the presence of a catalytic amount of perchlorate zinc hexahydrate. The present amination reaction proceeds quickly at rt (<30 min needed for most tested substrates) to provide the corresponding α-<i>N</i>-tosylamido β-dicarbonyl compounds in high to excellent yields

Hypervalent-Iodine-Mediated Ring-Contraction Monofluorination Affording Monofluorinated Five-Membered Ring-Fused Oxazolines

The first ring-contraction monofluorination reaction mediated by a hypervalent iodine reagent is reported, and the use of the reaction for the synthesis of monofluorinated five-membered ring-fused oxazolines is described. By means of this reaction, a fluorine atom can be selectively introduced either on the five-membered ring or external to it, depending on whether or not the substrate has C-4 alkyl substituents. The reaction was used for the further conversion of probenecid and isoxepac

Flexible Polydimethylsilane Nanocomposites Enhanced with a Three-Dimensional Graphene/Carbon Nanotube Bicontinuous Framework for High-Performance Electromagnetic Interference Shielding

High-performance electromagnetic interference (EMI)-shielding materials featuring lightweight, flexibility, excellent conductivity, and shielding properties, as well as superior mechanical robustness, are highly required, yet their development still remains a daunting challenge. Here, a flexible and exceptional EMI-shielding polydimethylsilane/reduced graphene oxide/single-wall carbon nanotube (PDMS/rGO/SWCNT) nanocomposite was developed by a facile backfilling approach utilizing a preformed rGO/SWCNT aerogel as the three-dimensional (3D) conducting and reinforcement skeleton. Pristine SWCNTs acting as secondary conductive fillers showed intriguing advantages, whose intrinsically high conductivity could be well preserved in the composites because of no surface acidification treatment. The robust and interconnected 3D network can not only serve as fast channels for electron transport but also effectively transfer external load. Accordingly, a prominent electrical conductivity of 1.2 S cm^–1 and an outstanding EMI-shielding effectiveness of around 31 dB over the X-band frequency range were achieved for the resultant composite with an ultralow loading of 0.28 wt %, which is among the best results for currently reported conductive polymer nanocomposites. Moreover, the composite displayed excellent mechanical properties and bending stability; for example, a 233% increment in the compression strength was obtained compared with that of neat PDMS. These observations indicate the unrivalled effectiveness of 3D rGO/SWCNT aerogel as a reinforcement to endow the polymer composites with outstanding conductive and mechanical properties toward high-performance EMI-shielding application

TIPE2 deficiency increases NO production but decreases urea production in macropahges.

<p>Peritoneal macrophages from WT and <i>TIPE2^−/−</i> mice were treated with 100 ng/mL LPS for 0 h, 3 h, and 24 h. iNOS mRNA (<b>A</b>) and protein (<b>B</b>) levels were determined by quantitative PCR and Western blot, respectively. Expression levels of arginase I and arginase II mRNA were examined by quantitative RT-PCR (<b>D</b> and <b>C</b>). Cells were stimulated with 100 ng/mL LPS for 24 h, and culture supernatants were harvested for measurement of NO and urea (<b>E</b> and <b>F</b>). Data are shown as means ±SE (n = 4) of one representative experiment. *<i>P</i><0.05.</p

Effect of TIPE2 Overexpression on LPS-induced iNOS expression.

<p>RAW264.7 cells were stably transfected with TIPE2 plasmid or vector control. TIPE2 expression levels were determined by quantitative RT-PCR (<b>A</b>) and Western blot (<b>B</b>), respectively. For quantitative PCR, the results were presented as folds expression of TIPE2 RNA to that of β-actin. TIPE2 overexpression RAW264.7 cells or control cells were treated with 100 ng/mL LPS for 24 h, and iNOS mRNA (<b>C</b>) and protein (<b>D</b>) levels were detected by quantitative PCR and Western blot, respectively. Data are shown as mean ±SE of one representative experiment. **<i>P</i><0.01; ***<i>P</i><0.001.</p

Regulation and Methylation of Tumor Suppressor MiR-124 by Androgen Receptor in Prostate Cancer Cells

<div><p>Prostate cancer (PCa) is the most frequently diagnosed cancer for men in the developed world. Androgen receptor signaling pathway plays an important role in prostate cancer progression. Recent studies show that microRNA miR-124 exerts a tumor suppressive function in prostate cancer. However, the relationship between AR and miR-124 is unclear. In the present study, we found a negative feedback loop between AR and miR-124 expression. On one hand, miR-124 was a positively regulated target gene of the AR, on the other hand, overexpression of miR-124 inhibited the expression of AR. In addition, we found that miR-124-2 and miR-124-3 promoters were hypermethylated in AR-negative PCa cells. Furthermore, overexpression of miR-124 inhibited proliferation rates and invasiveness capacity of PCa cells <i>in vitro</i>, and suppressed xenograft tumor growth <i>in vivo</i>. Taken together, our results support a negative feedback loop between AR and miR-124 expression. Methylation of miR-124-2 and miR-124-3 may serve as a biomarker for AR-negative PCa cells, and overexpression of miR-124 might be of potential therapeutic value for the treatment of PCa.</p></div

Flexible Polydimethylsilane Nanocomposites Enhanced with a Three-Dimensional Graphene/Carbon Nanotube Bicontinuous Framework for High-Performance Electromagnetic Interference Shielding

High-performance electromagnetic interference (EMI)-shielding materials featuring lightweight, flexibility, excellent conductivity, and shielding properties, as well as superior mechanical robustness, are highly required, yet their development still remains a daunting challenge. Here, a flexible and exceptional EMI-shielding polydimethylsilane/reduced graphene oxide/single-wall carbon nanotube (PDMS/rGO/SWCNT) nanocomposite was developed by a facile backfilling approach utilizing a preformed rGO/SWCNT aerogel as the three-dimensional (3D) conducting and reinforcement skeleton. Pristine SWCNTs acting as secondary conductive fillers showed intriguing advantages, whose intrinsically high conductivity could be well preserved in the composites because of no surface acidification treatment. The robust and interconnected 3D network can not only serve as fast channels for electron transport but also effectively transfer external load. Accordingly, a prominent electrical conductivity of 1.2 S cm^–1 and an outstanding EMI-shielding effectiveness of around 31 dB over the X-band frequency range were achieved for the resultant composite with an ultralow loading of 0.28 wt %, which is among the best results for currently reported conductive polymer nanocomposites. Moreover, the composite displayed excellent mechanical properties and bending stability; for example, a 233% increment in the compression strength was obtained compared with that of neat PDMS. These observations indicate the unrivalled effectiveness of 3D rGO/SWCNT aerogel as a reinforcement to endow the polymer composites with outstanding conductive and mechanical properties toward high-performance EMI-shielding application

A Negative Feedback Loop Between MiR124 and AR Expression.

<p>(A) PC3/AR cells are a stable cell line overexpressing human AR cDNA; PC3/neo cells are used as a control. (B) LNCaP-sh-AR cells are AR-knockdown cells, in which LNCaP cells were infected with lentivious AR shRNA; LNCaP-sh-control cells are used as a control. (C) 0 nM, 1 nM and 10 nM DHT were added to LNCaP cells and cultured for 12 hour. (D) LNCaP cells were infected with a control lentivirus (LNCaP-control cells) or plenti-CMV-mir-124 lentivirus (LNCaP-miR-124 cells). Relative expression of miR-124 in LNCaP cells was determined by qRT-PCR and corrected to RUN44 levels. Values mean fold-changes normalized to (A) PC3/neo cells; (B) LNCaP-sh-AR cell; (C) LNCaP cells (0 nM DHT) and (D) LNCaP-control cells. (E) Relative expression of AR was determined by qRT-PCR and normalized to β-actin levels. Values mean fold-changes normalized to LNCaP-control cells. (F) A schematic diagram of the pathway described in the study. Data are shown as the means ± SEM from 3 independent experiments, each of which were performed in triplicates</p

Flexible Polydimethylsilane Nanocomposites Enhanced with a Three-Dimensional Graphene/Carbon Nanotube Bicontinuous Framework for High-Performance Electromagnetic Interference Shielding

High-performance electromagnetic interference (EMI)-shielding materials featuring lightweight, flexibility, excellent conductivity, and shielding properties, as well as superior mechanical robustness, are highly required, yet their development still remains a daunting challenge. Here, a flexible and exceptional EMI-shielding polydimethylsilane/reduced graphene oxide/single-wall carbon nanotube (PDMS/rGO/SWCNT) nanocomposite was developed by a facile backfilling approach utilizing a preformed rGO/SWCNT aerogel as the three-dimensional (3D) conducting and reinforcement skeleton. Pristine SWCNTs acting as secondary conductive fillers showed intriguing advantages, whose intrinsically high conductivity could be well preserved in the composites because of no surface acidification treatment. The robust and interconnected 3D network can not only serve as fast channels for electron transport but also effectively transfer external load. Accordingly, a prominent electrical conductivity of 1.2 S cm^–1 and an outstanding EMI-shielding effectiveness of around 31 dB over the X-band frequency range were achieved for the resultant composite with an ultralow loading of 0.28 wt %, which is among the best results for currently reported conductive polymer nanocomposites. Moreover, the composite displayed excellent mechanical properties and bending stability; for example, a 233% increment in the compression strength was obtained compared with that of neat PDMS. These observations indicate the unrivalled effectiveness of 3D rGO/SWCNT aerogel as a reinforcement to endow the polymer composites with outstanding conductive and mechanical properties toward high-performance EMI-shielding application