Structural distortion of g-C3N4 induced by a schiff base reaction for efficient photocatalytic H2 evolution.

Photocatalytic H2 evolution by water splitting is a promising approach to address the challenges of environmental pollution and energy scarcity. Graphitic carbon nitride (g-C3N4) has emerged as a star photocatalyst because of its numerous advantages. To address the limitations of traditional g-C3N4, namely its inadequate visible light response and rapid recombination of photogenerated carriers, we employed a schiff base reaction to synthesize -C=N- doped g-C3N4. The introduction of -C=N- groups at the bridging nitrogen sites induced structural distortion in g-C3N4, facilitating n-π* electronic transitions from the lone pair electrons of nitrogen atom and extending light absorption up to 600 nm. Moreover, the presence of heterogeneous π-conjugated electron distribution effectively traps photogenerated electrons and enhances charge carrier separation. Benefiting from its expanded spectral response range, unique electronic properties, increased specific surface area, the doped g-C3N4 exhibited outstanding photocatalytic H2 evolution performance of 1050.13 µmol/g/h. The value was 5.9 times greater than the pristine g-C3N4.

MiR-15b-5p Promotes Growth and Metastasis of Renal Clear Cell Carcinoma / MiR-15b-5p Promueve el Crecimiento y la Metástasis del Carcinoma Renal de Células Claras

SUMMARY: We investigated the expression and clinical significance of miR-15b-5p in clear cell renal cell carcinoma (RCC) through bioinformatics analysis and experimental verification. The differentially expressed miRNAs were screened in the GEO database. Venn diagram showed that there were 5 up-regulated miRNAs (has-miR-210, has-miR-142-3p, has-miR-142-5p, has-miR-15b-5p, and has-miR-193a-3p) and only 1 down-regulated miRNA (has-miR-532-3p) that were commonly expressed between GSE189331 and GSE16441 datasets. This was further confirmed in TCGA. Further analysis showed that the has-miR-193a-3p, has-miR-142-3p, has- miR-142-5p, and has-miR-15b-5p were closely related to tumor invasion, distant metastasis and survival probability. The expression of miR-15b-5p in ccRCC tissues was significantly higher than that in adjacent normal kidney tissues (P0.05). Following inhibition of miR-15b-5p expression, RCC cells had attenuated proliferation, increased apoptosis, and attenuated migration and invasion. has-miR-15b-5p-WEE1, has-miR-15b-5p-EIF4E, has-miR-15b-5p-PPP2R1B may be three potential regulatory pathways in ccRCC. miR-15b-5p is highly expressed in cancer tissues of ccRCC patients. It may promote proliferation, inhibit apoptosis and enhance cell migration and invasion of RCC cells. The has-miR-15b-5p-WEE1, has-miR-15b-5p-EIF4E, and has-miR-15b-5p-PPP2R1B may be three potential regulatory pathways in ccRCC.

Investigamos la expresión y la importancia clínica de miR-15b-5p en el carcinoma de células renales (CCR) de células claras mediante análisis bioinformático y verificación experimental. Los miARN expresados diferencialmente se examinaron en la base de datos GEO. El diagrama de Venn mostró que había 5 miARN regulados positivamente (has-miR-210, has-miR-142-3p, has-miR-142-5p, has-miR-15b-5p y has-miR-193a-3p). ) y solo 1 miARN regulado negativamente (has-miR-532-3p) que se expresaron comúnmente entre los conjuntos de datos GSE189331 y GSE16441. Esto fue confirmado aún más en TCGA. Un análisis más detallado mostró que has-miR-193a-3p, has-miR-142-3p, has- miR-142-5p y has-miR-15b-5p estaban estrechamente relacionados con la invasión tumoral, la metástasis a distancia y la probabilidad de supervivencia. La expresión de miR-15b-5p en tejidos ccRCC fue significativamente mayor que la de los tejidos renales normales adyacentes (P 0,05). Tras la inhibición de la expresión de miR-15b-5p, las células RCC tuvieron una proliferación atenuada, un aumento de la apoptosis y una migración e invasión atenuadas. has-miR-15b-5p-WEE1, has- miR-15b-5p-EIF4E, has-miR-15b-5p-PPP2R1B pueden ser tres posibles vías reguladoras en ccRCC. miR-15b-5p se expresa altamente en tejidos cancerosos de pacientes con ccRCC. Puede promover la proliferación, inhibir la apoptosis y mejorar la migración celular y la invasión de células RCC. has-miR-15b-5p-WEE1, has- miR-15b-5p-EIF4E y has-miR-15b-5p-PPP2R1B pueden ser tres posibles vías reguladoras en ccRCC.

Synergy of MoO2 with Pt as Unilateral Dual Cocatalyst for Improving Photocatalytic Hydrogen Evolution over g-C3 N4.

Pt is usually used as cocatalyst for g-C3 N4 to produce H2 by photocatalytic splitting of water. However, the photocatalytic performance is still limited by the fast recombination of photo-generated electrons and holes, as well as the poor absorption of visible light. In this work, MoO2 /g-C3 N4 composites were prepared, in which MoO2 synergetic with Pt photo-deposited during H2 evolution reaction worked as unilateral dual cocatalyst to improve the photocatalytic activity. Within 4 hours of irradiation, the hydrogen production rate of MoO2 -Pt dual cocatalyst modified g-C3 N4 reached 3804.89 µmol/g/h, which was 120.18 times of that of pure g-C3 N4 (GCN, 31.66 µmol/g/h), 10.98 times of that of MoO2 modified g-C3 N4 (346.39 µmol/g/h), and 9.18 times of that of Pt modified g-C3 N4 (413.64 µmol/g/h). Characterization results demonstrate that the deficient MoO2 not only promoted visible light absorption of g-C3 N4 , but also worked as a "electron pool" to capture and transfer electrons to Pt.