Self-Powered Implantable Skin-Like Glucometer for Real-Time Detection of Blood Glucose Level In Vivo

Implantable bioelectronics for analyzing physiological biomarkers has recently been recognized as a promising technique in medical treatment or diagnostics. In this study, we developed a self-powered implantable skinlike glucometer for real-time detection of blood glucose level in vivo. Based on the piezo-enzymatic-reaction coupling effect of GOx@ZnO nanowire, the device under an applied deformation can actively output piezoelectric signal containing the glucose-detecting information. No external electricity power source or battery is needed for this device, and the outputting piezoelectric voltage acts as both the biosensing signal and electricity power. A practical application of the skin-like glucometer implanted in mouse body for detecting blood glucose level has been simply demonstrated. These results provide a new technique path for diabetes prophylaxis and treatment.

Calcium-dependent protein kinases CPK21 and CPK23 phosphorylate and activate the iron-regulated transporter IRT1 to regulate iron deficiency in Arabidopsis

Iron(Fe)is an essential micronutrient for all organisms.Fe availability in the soil is usually much lower than that required for plant growth,and Fe deficiencies seriously restrict crop growth and yield.Calcium(Ca2+)is a second messenger in all eukaryotes;however,it remains largely unknown how Ca2+regulates Fe deficiency.In this study,mutations in CPK21 and CPK23,which are two highly homologous calcium-dependent protein kinases,conferredimpaired growth and rootdevelopment under Fe-deficient conditions,whereas constitutively active CPK21 and CPK23 enhanced plant tolerance to Fe-deficient conditions.Furthermore,we found that CPK21 and CPK23 interacted with and phosphorylated the Fe transporter IRONREGULATED TRANSPORTER1(IRT1)at the Ser149 residue.Biochemical analyses and complementation of Fe transport in yeast and plants indicated that IRT1 Ser149 is critical for IRT1 transport activity.Taken together,these findings suggest that the CPK21/23-IRT1 signaling pathway is critical for Fe homeostasis in plants and provides targets for improving Fe-deficient environments and breeding crops resistant to Fe-deficient conditions.

Enhanced Photothermal Selective Conversion of CO_(2)to CH4 in Water Vapor over Rod-Like Cu and N Co-Doped TiO_(2)

Enhancing catalytic efficiency and selectivity is critical issues for CO_(2) conversion.The rod-like Cu/N co-doped TiO_(2) samples(Cu/N-TiO_(2)) were synthesized by the electrospinning-calcination method.The substitutional Cu and interstitial N doping not only enhanced visible-light absorption ability,but also formed the Ti(Ⅲ)sites.The obviously synergistic effect between the photocatalysis and thermalcatalysis appeared for CO_(2) conversion over the 8-Cu/N-TiO_(2) catalyst.After 9 h visible-light-illumination at 160℃,the CO,CH4and O_(2) yields reached 49.7,1455.1 and 2910.2μmol/gcat,respectively.In the 7thcycling,the yields of two main CH4and O_(2) products were slightly down by less than 11.5%,and the selectivity of CH_(4) product kept above 98%.Combined with the theoretical surface mode,Cu/N co-doping could promote the adsorption-ability for H_(2)O and CO_(2) molecules and reduce activation-energy for CO_(2)conversion.Hence,the co-doping construction showed a great significance of designing efficient photothermal catalysts for the CO_(2)conversion application.

GTPase ROP6 negatively modulates phosphate deficiency through inhibition of PHT1;1 and PHT1;4 in Arabidopsis thaliana

Phosphorus,an essential macroelement for plant growth and development,is a major limiting factor for sustainable crop yield.The Rho of plant(ROP)GTPase is involved in regulating multiple signal transduction processes in plants,but potentially including the phosphate deficiency signaling pathway remains unknown.Here,we identified that the rop6 mutant exhibited a dramatic tolerant phenotype under Pi-deficient conditions,with higher phosphate accumulation and lower anthocyanin content.In contrast,the rop6 mutant was more sensitive to arsenate(As(V))toxicity,the analog of Pi.Immunoblot analysis displayed that the ROP6 protein was rapidly degraded through ubiquitin/26S proteasome pathway under Pi-deficient conditions.In addition,pull-down assay using GST-RIC1 demonstrated that the ROP6 activity was decreased obviously under Pi-deficient conditions.Strikingly,protein-protein interaction and two-voltage clamping assays demonstrated that ROP6 physically interacted with and inhibited the key phosphate uptake transporters PHT1;1 and PHT1;4 in vitro and in vivo.Moreover,genetic analysis showed that ROP6 functioned upstream of PHT1;1 and PHT1;4.Thus,we conclude that GTPase ROP6 modulates the uptake of phosphate by inhibiting the activities of PHT1;1 and PHT1;4 in Arabidopsis.