Proteome reveals the mechanism of selenium-sulfur interaction in regulating isothiocyanate biosynthesis and the physiological metabolism of broccoli sprouts.

Broccoli sprouts have a strong ability to accumulate isothiocyanate and selenium. In this study, the isothiocyanate content increased significantly as a result of ZnSO4 stress. Particularly, based on the isothiocyanate content is not affected, the combined ZnSO4 and Na2SeO3 treatment alleviated the inhibition of ZnSO4 and induced selenium content. Gene transcription and protein expression analyses revealed the changes in isothiocyanate and selenium metabolite levels in broccoli sprouts. ZnSO4 combined with Na2SeO3 was proven to activate a series of isothiocyanate metabolite genes (UGT74B1, OX1, and ST5b) and selenium metabolite genes (BoSultr1;1, BoCOQ5-2, and BoHMT1). The relative abundance of the total 317 and 203 proteins, respectively, in 4-day-old broccoli sprouts varied, and the metabolic and biosynthetic pathways for secondary metabolites were significantly enriched in ZnSO4/control and ZnSO4 combined Na2SeO3/ZnSO4 comparisons. The findings demonstrated how ZnSO4 combined with Na2SeO3 treatment reduced stress inhibition and the accumulation of encouraged selenium and isothiocyanates during the growth of broccoli sprouts.

Reduced graphene oxide nanosheets decorated with core-shell of Fe3O4-Au nanoparticles for rapid SERS detection and hyperthermia treatment of bacteria.

In this study, the core-shell of Fe3O4-Au nanoparticles (NPs) were prepared by seeding AuNPs onto Fe3O4 NPs modified with poly-ethylenimine (PEI). Later, Fe3O4-Au NPs were attached to cationic poly(dimethyldiallylammonium chloride) (PDDA)-modified graphene oxide (GO) nanosheets through in situ self-assembly behaviors, termed as Fe3O4-Au@RGO nanocomposites, for surface-enhanced Raman scattering (SERS) detection and hyperthermia treatment of bacteria. The resulting Fe3O4-Au@RGO nanocomposites were evaluated systematically by transmission electron microscope, zeta potential, X-ray diffraction, X-ray photoelectron spectroscopy, and vibrating sample magnetometer. It revealed that the core-shell structured Fe3O4-Au NPs were dispersed homogeneously on the surface of the GO nanosheets. Furthermore, the rapid SERS detection for small biomolecules and bacteria was conducted by Raman spectroscopy. The results showed that the greatest SERS intensity was fne tuned at the weight ratio of Fe3O4-Au/RGO nanosheets was 20/1, displaying the optimal interparticle gap of AuNPs to induce the huge hot-spots effect. The magnetic inductive heating capability of Fe3O4-Au@RGO nanocomposites was produced under high frequency magnetic field exposure and can kill high than 90% of the bacteria at 10 min. Hence, the newly developed Fe3O4-Au@RGO nanocomposites were demonstrated to be viable for SERS detection of biomolecules and microbes and potential applications for magnetically capturing and hyperthermia treatment of bacteria.

Neural network study for standardizing pulse-taking depth by the width of artery.

To carry out a pulse diagnosis, a traditional Chinese medicine (TCM) physician presses the patient's wrist artery at three incremental depths, namely Fu (superficial), Zhong (medium), and Chen (deep). However, the definitions of the three depths are insufficiently clear for use with modern pulse diagnosis instruments (PDIs). In this paper, a quantitative method is proposed to express the pulse-taking depths based on the width of the artery (WA). Furthermore, an index, α, is developed for estimating WA for PDI application. The α value is obtained using an artificial neural network (ANN) model with contact pressure (CP) and sensor displacement (SD) as the inputs. The WA and SD data from an ultrasound instrument and CP and SD data from a PDI were analyzed. The results show that the mean prediction error and the standard deviation (STD) of the ANN model was 1.19% and 0.0467, respectively. Comparing the ANN model with the SD model by statistical method, it showed significant difference and the improvement in the mean prediction error and the STD was 71.62% and 29.78%, respectively. The α value can thus map WA with less individual variation than that of the values estimated directly using the SD model. Pulse signals at different depths thus can be acquired according to α value while using a PDI, providing TCM physicians with more reliable pulse information.

Ligase detection reaction/hybridization assays using three-dimensional microfluidic networks for the detection of low-abundant DNA point mutations.

We have fabricated a flow-through biochip assembly that consisted of two different microchips: (1) a polycarbonate (PC) chip for performing an allele-specific ligation detection reaction (LDR) and (2) a poly(methyl methacrylate) (PMMA) chip for the detection of the LDR products using an universal array platform. The operation of the device was demonstrated by detecting low-abundant DNA mutations in gene fragments (K-ras) that carry point mutations with high diagnostic value for colorectal cancers. The PC microchip was used for the LDR in a continuous-flow format, in which two primers (discriminating primer that carried the complement base to the mutation being interrogated and a common primer) that flanked the point mutation and were ligated only when the particular mutation was present in the genomic DNA. The miniaturized reactor architecture allowed enhanced reaction speed due to its high surface-to-volume ratio and efficient thermal management capabilities. A PMMA chip was employed as the microarray device, where zip code sequences (24-mers), which were complementary to sequences present on the target, were microprinted into fluidic channels embossed into the PMMA substrate. Microfluidic addressing of the array reduced the hybridization time significantly through enhanced mass transport to the surface-tethered zip code probes. The two microchips were assembled as a single integrated unit with a novel interconnect concept to produce the flow-through microfluidic biochip. A microgasket, fabricated from an elastomer poly(dimethylsiloxane) with a total volume of the interconnecting assembly of <200 nL, was used as the interconnect between the two chips to produce the three-dimensional microfluidic network. We successfully demonstrated the ability to detect one mutant DNA in 100 normal sequences with the biochip assembly. The LDR/hybridization assay using the assembly performed the entire assay at a relatively fast processing speed: 6.5 min for on-chip LDR, 10 min for washing, and 2.6 min for fluorescence scanning (total processing time 19.1 min) and could screen multiple mutations simultaneously.