Self-formed silver nanoparticles on freestanding silicon nanowire arrays featuring SERS performances.

Herein, the universal luminescence characteristics of porous Si nanowire arrays were exploited using a wide range of doping types and concentrations; we found that the dual-band photoluminescence intensities were correlated with the formation rates of Si nanowires with porous features; however, these intensities exhibited no evident dependence on the doping conditions. Furthermore, we demonstrated a facile and reliable transfer method implementing the freestanding Si nanowire arrays while maintaining the robust photoluminescence behaviors under bending conditions. The fabrication protocol, involving lateral etching locally at the nanowire ends, enabled the controlled formation of uniform and large-area transferred nanowires with vertical regularity. Without the additional deposition of Ag nanoparticles, these transferred Si nanowire films inherently possessed SERS sensing capability with a relative enhancement factor over 1.8 times that of the Si nanowires with electroless-deposited Ag nanoparticles, which could practically emerge as a functional design for the integration of practical biochip devices.

Paraptosis-Inducing Nanomedicine Overcomes Cancer Drug Resistance for a Potent Cancer Therapy.

Most chemotherapeutic drugs and their nanomedicine formulations exert anticancer activity by inducing cancer cell apoptosis. However, cancer cells inherently have and acquire many antiapoptosis mechanisms, causing cancer drug resistance and poor prognoses in patients. Herein, a potent paraptosis-inducing nanomedicine is reported that causes quick nonapoptotic death of cancer cells, overcoming apoptosis-based resistance and effectively inhibiting drug-resistant tumor growth. The nanomedicine is composed of micelles made from an amphiphilic 8-hydroxyquinoline (HQ)-conjugate block copolymer with polyethylene glycol. Cu2+ can catalyze the hydrolysis of the HQ conjugation linker and liberate HQ, and these molecules can form the complex Cu(HQ)2 , a strong proteasome inhibitor effective at inducing cell paraptosis. In vivo, the Cu2+ -responsive HQ-releasing micelles respond to elevated tumor Cu2+ levels or externally administered Cu2+ and effectively inhibit the growth of human breast adenocarcinoma doxorubicin-resistant (MCF-7/ADR) tumors. Compared with other nanomedicines that overcome drug resistance via delivering several agents or even siRNA, this paraptosis-inducing nanomedicine provides a simple but potent approach to overcoming cancer drug resistance.

Synergistic Improvement in Thermal Conductivity of Polyimide Nanocomposite Films Using Boron Nitride Coated Copper Nanoparticles and Nanowires.

Electronic devices are increasingly dense, underscoring the need for effective thermal management. A polyimide (PI) matrix nanocomposite film combining boron nitride (BN)-coated copper nanoparticles (CuNPs@BN) and nanowires (CuNWs@BN) was fabricated by a flexible and fast technique for enhanced thermal conductivity and the dielectric properties of nanocomposite films. The thermal conductivity of (CuNPs-CuNWs)@BN/PI composite comprising 10 wt % filler loading rose to 4.32 W/mK, indicating a nearly 24.1-fold increase relative to the value obtained for pure PI matrix. The relative permittivity and dielectric loss approximated 4.92 and 0.026 at 1 MHz, respectively. The results indicated that the surface modification of CuNPs and CuNWs by introducing a ceramic insulating layer BN effectively promoted the formation of thermal conductive networks of nanofillers in the PI matrix. This study enabled the identification of appropriate modifier fillers for polymer matrix nanocomposites to improve electronic applications.

GDC-0449 improves the antitumor activity of nano-doxorubicin in pancreatic cancer in a fibroblast-enriched microenvironment.

Pancreatic cancer is one of the most lethal human cancers that currently does not have effective therapies. Novel treatments including nanomedicines and combination therapies are thus urgently needed for these types of deadly diseases. A key feature of pancreatic cancer is its tumor protective dense stroma, which is generated by cancer-associated fibroblasts (CAFs). The interaction between CAFs and pancreatic cancer cells abnormally activates sonic hedgehog (SHH) signaling and facilitates tumor growth, metastasis, and drug resistance. Here, we report that the commercial SHH inhibitor GDC-0449 reverses fibroblast-induced resistance to doxorubicin in Smoothened (SMO)-positive pancreatic cancer cells by downregulating SHH signaling proteins. Importantly, the synergistic combination of GDC-0449 with PEG-PCL-Dox exhibited potent antitumor efficacy in a BxPC-3 tumor xenograft model, whereas single treatments did not significantly inhibit tumor growth. Our findings reveal a potential treatment strategy for fibroblast-enriched pancreatic cancer.

Long Noncoding RNA CRNDE Promotes Multiple Myeloma Cell Growth by Suppressing miR-451.

It has been determined that long noncoding RNAs (lncRNAs) are identified as a potential regulatory factor in multiple tumors as well as multiple myeloma (MM). However, the role of colorectal neoplasia differentially expressed (CRNDE) in the pathogenesis of MM remains unclear. In this study, we found that the CRNDE expression level, in MM samples and cell lines, is higher than that in the control detected by real-time qPCR, which is also closely related to tumor progression and poor survival in MM patients. Knockdown of CRNDE significantly inhibits the proliferative vitality of MM cells (U266 and RPMI-8226), induces cell cycle arrest in the G0/G1 phase, and promotes apoptosis. After being transfected with siRNA, miR-451 expression observably increases. Bioinformatics analysis and luciferase assay reveal the interaction by complementary bonding between CRNDE and miR-451. Pearson's correlation shows that CRNDE is negatively correlated to miR-451 expression in human MM samples. Subsequently, miR-451 inhibitor rescues the inhibited tumorigenesis induced by CRNDE knockdown. Our study illustrates that lncRNA CRNDE induces the proliferation and antiapoptosis capability of MM by acting as a ceRNA or molecular sponge via negatively targeting miR-451, which could act as a novel diagnostic marker and therapeutic target for MM.

The use of polyimide-modified aluminum nitride fillers in AlN@PI/epoxy composites with enhanced thermal conductivity for electronic encapsulation.

Polymer modified fillers in composites has attracted the attention of numerous researchers. These fillers are composed of core-shell structures that exhibit enhanced physical and chemical properties that are associated with shell surface control and encapsulated core materials. In this study, we have described an apt method to prepare polyimide (PI)-modified aluminum nitride (AlN) fillers, AlN@PI. These fillers are used for electronic encapsulation in high performance polymer composites. Compared with that of untreated AlN composite, these AlN@PI/epoxy composites exhibit better thermal and dielectric properties. At 40 wt% of filler loading, the highest thermal conductivity of AlN@PI/epoxy composite reached 2.03 W/mK. In this way, the thermal conductivity is approximately enhanced by 10.6 times than that of the used epoxy matrix. The experimental results exhibiting the thermal conductivity of AlN@PI/epoxy composites were in good agreement with the values calculated from the parallel conduction model. This research work describes an effective pathway that modifies the surface of fillers with polymer coating. Furthermore, this novel technique improves the thermal and dielectric properties of fillers and these can be used extensively for electronic packaging applications.

A poly(vinylidene fluoride) composite with added self-passivated microaluminum and nanoaluminum particles for enhanced thermal conductivity.

A polymer composite was prepared by embedding fillers made of self-passivated aluminum particles in two kind of sizes, micrometer size and nanometer size with different volume proportions into polyvinylidene fluoride matrix. The thermal conductivity and dielectric properties of the composite were studied. The results showed that the thermal conductivity of composites was significantly increased to 3.258 W∕mK when the volume proportion of micrometer size Al particles to nanometer size Al particles is at 20:1, also the relative permittivity was about 75.8 at 1 MHz. The effective simulation model values were in good accordance with experimental results.