DNA-Programmed Tuning of the Growth and Enzyme-Like Activity of a Bimetallic Nanozyme and Its Biosensing Applications.

Nanozymes, which combine the merits of both nanomaterials and natural enzymes, have aroused tremendous attention as new representatives of artificial enzyme mimics. However, it still remains to be a great challenge to rationally engineer the morphologies and surface properties of nanostructures that lead to the desired enzyme-like activities. Here, we report a DNA-programming seed-growth strategy to mediate the growth of platinum nanoparticles (PtNPs) on gold bipyramids (AuBPs) for the synthesis of a bimetallic nanozyme. We find that the preparation of a bimetallic nanozyme is in a sequence-dependent manner, and the encoding of a polyT sequence allows the successful formation of bimetallic nanohybrids with greatly enhanced peroxidase-like activity. We further observe that the morphologies and optical properties of T15-mediated Au/Pt nanostructures (Au/T15/Pt) change over the reaction time, and the nanozymatic activity can be tuned by controlling the experimental conditions. As a concept application, Au/T15/Pt nanozymes are used to establish a simple, sensitive, and selective colorimetric assay for the determination of ascorbic acid (AA), alkaline phosphatase (ALP), and the inhibitor sodium vanadate (Na3VO4), demonstrating excellent analytical performance. This work provides a new avenue for the rational design of bimetallic nanozymes for biosensing applications.

Bismuth-doped g-C3N4/ZIF-8 heterojunction photocatalysts with enhanced photocatalytic performance under visible light illumination.

In this work, g-C3N4/ZIF-8 heterojunction photocatalysts were synthesised by the process by which the metal-organic framework ZIF-8 nanoparticles were grown onto the g-C3N4 layer in situ. Bismuth element was doped into the as-prepared g-C3N4/ZIF-8 material and a new type of Bi@g-C3N4/ZIF-8 composite photocatalysts was manufactured, in which the doping element acts in adjusting the bandgap in the photocatalysts. The prepared photocatalysts were characterised by XRD, FESEM, TEM, FTIR, XPS, UV-VIS DRS, photoluminescence and photo-electrochemical experiments. The results show that the ZIF-8 nanoparticles grown in situ were well-formed onto the g-C3N4 layer, and bismuth was evenly doped into the gaps of the g-C3N4/ZIF-8 framework. The degradation rate of methylene blue by CNZ-1.5(Bi)-12, which was a photocatalyst composed of 12% Bi-doped with g-C3N4/ZIF-8 material (the mass ratio of g-C3N4: ZIF-8 = 1:1.5), reached 86.6% under visible light irradiation within 60 min. The free radical scavenging experiment and electron spin resonance spectroscopy showed that ∙OH was the main active substance. Bismuth doping into the photocatalytic system promotes the excitation of electrons from the valence band to the conduction band and provides a good channel for the transmission of photogenerated carriers as well. It is achieved that intensive visible light absorption, the enhanced separation efficiency of photogenerated carriers, and excellent thermal stability and high recyclability in the novel composite photocatalyst, owing to the synergistic effect of the introduced bismuth with the heterostructure of g-C3N4/ZIF-8. Therefore, the synthesised Bi@g-C3N4/ZIF-8 heterojunction photocatalysts may be used as a good photocatalyst for purifying and degrading organic matter in sewage.

Pelvic cavity malignant solitary fibrous tumor with dedifferentiation and multifocal cytokeratin expression.

Pelvic cavity small-sized malignant solitary fibrous tumors are rare. Surgeons easily misjudge these tumors as benign lesions, and they are usually resected by laparoscopic surgery. When accompanied by dedifferentiation, malignant solitary fibrous tumors are difficult to diagnose by pathologists. Here, we describe a challenging case. A 47-year-old man was accidentally found to have a pelvic mass after three months. Surgeons assumed a diagnosis of a benign tumor according to the Computed Tomography and Ultrasonography reports. The patient underwent laparoscopic surgery to resect the tumor. After the operation, the patient was diagnosed as having a malignant solitary fibrous tumor with dedifferentiation. The patient had a recurrence one year later. This pelvic cavity malignant solitary fibrous tumor was a rare case because of its dedifferentiation and cytokeratin expression. The expression of cytokeratin and the absence of vimentin and CD34 were pitfalls to diagnosis. In this case, there was still a high amount of malignancy despite the small size of the tumor. Clinical image and pathologic multidisciplinary analysis and core needle biopsies before surgery had a great effect on diagnosis and therapy of this disease. The case is a cautionary tale not only for pathologists but also for surgeons.

Intravascular fasciitis of the hip joint in a postpartum female: misdiagnosed as low grade fibromyxoid sarcoma.

Intravascular fasciitis is a special type of nodular fasciitis. It is an uncommon lesion. We report here the first case of intravascular fasciitis involving the deep muscle of the hip joint. The female, postpartum patient presented with a large, firm, painless tumoral mass in the anterolateral muscles of the right hip. The diagnosis of intravascular fasciitis was difficult because of the large size and location of the lesion. The false positive immunohistochemistry for MUC4 initially caused our team to misdiagnose the intravascular fasciitis as a low grade malignant fibromyxoid sarcoma. Our case adds to the literature on intravascular fasciitis. Since the operation about 20 months prior, the tumor in this case has not recurred.

Facile synthesize of CdS QDs decorated Bi2MoO6/Bi2Mo3O12 heterojunction photocatalysts and enhanced performance of visible light removal of organic pollutants.

In this work, the CdS quantum dots (QDs) decorated Bi2MoO6/Bi2Mo3O12 (BMO) heterojunction photocatalyst (C/BMO) has been successfully synthesized using a facile two-step hydrothermal method. The as-prepared photocatalysts were characterized by XRD, FTIR, XPS, FESEM, TEM, UV-vis DRS, PL and photoelectrochemical measurements to investigate the effects of CdS(QDs) and BMO heterojunction on the structure, morphology, optical and charge carrier transmission characteristics of the photocatalysts. Narrow band gap and superior catalytic activities were found in C/BMO as compared with pure BMO. Moreover, the C/BMO photocatalyst containing twice CdS content (2-C/BMO) exhibits even higher photocatalytic activity and stability. After exposure to visible light for 30 min, the degradation rate of Rhodamine B (RhB), Methylene blue (MB) and Ofloxacin (OFX) by 2-C/BMO reached 95%, 92% and 76%, respectively. Radicals scavenging experiments and electron spin-resonance spectroscopy (ESR) investigations indicated that the superoxide radical anions (∙O2- ), hole (h+) and hydroxyl radicals (•OH) are the dominating active species in the photodegradation processes. ∙O2- and h+ are the key factors in the degradation of RhB and OFX solutions, and •OH is the major determinant in removal of MB. The process and photocatalytic mechanism on 2-C/BMO was discussed. Well absorption of visible light, effective separation of photoelectron-hole pairs and the transportation of photogenerated carriers at the interfaces of ternary semiconductor heterojunction are suggested as the key factors to enhance the photocatalytic performance of the photocatalysts.

Krüppel-like factor 2 inhibits hepatocarcinogenesis through negative regulation of the Hedgehog pathway.

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. The most important reason for the occurrence of HCC is hepatitis C or B infection. Moreover, genetic factors play an important role in the tumorigenesis of HCC. Here, we demonstrated that Krüppel-like factor 2 (KLF2) expression was downregulated in HCC samples compared with adjacent tissues. Additionally, KLF2 was shown to inhibit the growth, migration and colony-formation ability of liver cancer cells. Further mechanistic studies revealed that KLF2 can compete with Gli1 for interaction with HDAC1 and restrains Hedgehog signal activation. Together, our results suggest that KLF2 has potential as a diagnostic biomarker and therapeutic target for the treatment of HCC.