BiFeO 3 (BFO) is of considerable interest because of its potential applications in the design of devices combining magnetic, electronic, and optical functionalities. Effects of the Gd dopant on the structural, photocatalytic activity, and ferromagnetic properties of BFO nanoparticles have been studied. X-ray diffraction and Raman spectra results of Bi 1-x Gd x FeO 3 (BGFO x , x ) 0, 0.05, 0.1, and 0.15) reflect that the crystal structure of the samples remain stable for x < 0.1, while compositional-driven phase transition from rhombohedral to orthorhombic is observed at x ) 0.1. The photocatalytic activity to decompose Rhodamine-B under visiblelight illumination increases in BGFO x as x increases from zero to 0.1 and then decreases for x ) 0.15. The maximum in photocatalytic activity near the phase boundary of x ) 0.1 is associated with the changing of the polar behavior of the nanoparticles. Comparing with the linear magnetization-magnetic field (M-H) relation in pure BFO nanoparticles, obvious M-H loops can be observed in the doped samples, which are ascribed to the distorted spin cycloid and magnetically active characteristic of Gd 3+ ions.

Dysregulated alternative splicing events have been implicated in many types of cancer, but the underlying molecular mechanisms remain unclear. Here, we observe that the splicing factor SRSF1 regulates DBF4B exon6 splicing by specifically binding and promoting its inclusion. Knockdown of the exon6-containing isoform (DBF4B-FL) significantly inhibits the tumorigenic potential of colon cancer cells in vitro and in mice, and SRSF1 inactivation phenocopies DBF4B-FL depletion. DBF4B-FL and SRSF1 are required for cancer cell proliferation and for the maintenance of genomic stability. Overexpression of DBF4B-FL can protect against DNA damage induced by SRSF1 knockdown and rescues growth defects in SRSF1-depleted cells. Increased DBF4B exon6 inclusion parallels SRSF1 upregulation in clinical colorectal cancer samples. Taken together, our findings identify SRSF1 as a key regulator of DBF4B pre-mRNA splicing dysregulation in colon cancer, with possible clinical implications as candidate prognostic factors in cancer patients.

The shape of a drug delivery system impacts its in vivo behavior such as circulation time, accumulation, and penetration. Considering the advantages of functional dyes in bioapplications, we synthesize a class of nanoaggregates based on BF 2 -azadipyrromethene (aza-BODIPY) dyes, which can realize long blood circulation and deep tumor penetration simultaneously in vivo through morphological transformation modulated by a nearinfrared (NIR) laser. First, when the temperature increases, the wormlike nanofibers of the aza-BODIPY-1 aggregate, possessing a long blood circulation time, can be transformed into spherical nanoparticles, which are conducive to increasing the penetration in the solid tumor. Second, without any postmodification, the nanofibers exhibit an outstandingly narrow absorption band in the NIR spectral range, so that they possess ideal photothermal properties. Through 655 nm laser irradiation, the intrinsic photothermal effect causes a local temperature increase to ∼48 °C, realizing the transformation of 1-NFs to 1-NPs. Third, the morphological transformation is real-time detected by photoacoustic (PA) imaging. By monitoring the change of the PA signal at a specific wavelength, the in vivo deformation process of nanomaterials can be traced. Consequently, the in situ morphology transformation of aza-BODIPY-based nanomaterials can simultaneously realize long blood circulation and deep penetration, resulting in the enhanced antitumor outcome.

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Selenium nanoparticles (Se NPs) possess well-known excellent biological activities and low toxicity, and have been employed for numerous applications except as inhibitors to protein glycation. Herein, the present study is carried out to investigate the inhibitory effect of Se NPs on protein glycation in a bovine serum albumin (BSA)/glucose system. By measuring the amount of glucose covalently bound onto BSA, the formation of fructosamine and fluorescent products, it is found that Se NPs can hinder the development of protein glycation in a dose-dependent but time-independent manner under the selected reaction conditions (55 °C, 40 h). And after comparing the increase of inhibitory rate in different stages, it is observed that Se NPs show the greatest inhibitory effect in the early stage, then in the advanced stage, but no effect in the intermediate stage. Fourier transform infrared spectroscopy characterization of Se NPs collected after glycation and determination of ·OH influence and glyoxal formation show that the mechanism for the inhibitory efficacy of Se NPs is related to their strong competitive activity against available amino groups in proteins, their great scavenging activity on reactive oxygen species and their inhibitory effect on α-dicarbonyl compounds' formation. In addition, it is proved that Se NPs protect proteins from structural modifications in the system and they do not exhibit significant cytotoxicity towards BV-2 and BRL-3A cells at low concentrations (10 and 50 μg mL(-1)). Consequently, Se NPs may be suitable for further in vivo studies as novel anti-glycation agents.

Nanoceria (cerium oxide nanoparticles) exhibits excellent catalytic activity towards chromogenic substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H 2 O 2 ), which has been reported. However, the understanding on the interaction between H 2 O 2 and nanoceria is far from complete. Herein, we further studied the interaction between H 2 O 2 and dextran-coated nanoceria and found that H 2 O 2 plays a dual role on nanoceria's oxidase activity both as an inhibitor and a promoter, depending on its concentration. In millimolar levels, H 2 O 2 can promote nanoceria's oxidase activity, however, micromolar concentration of H 2 O 2 could inhibit its catalytic activity. In addition, this inhibiting effect is linearly dependent on the concentration of H 2 O 2 . Based on these findings, a simple, rapid and highly sensitive colorimetric method was established for the determination of H 2 O 2 with a limit of detection (LOD) of 2.5 µM (3σ/slope) and a linear range from 4−40 µM. When coupled with glucose oxidase, glucose can be detected down to 2 µM in the linear range of 4−40 µM. Furthermore, this method was successfully applied for the determination of glucose in mouse serum samples. With the new understanding of the interaction between H 2 O 2 and nanoceria, applications of nanoceria-based sensors in engineering, biotechnology and environmental chemistry can be further exploited.