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As a typical mimic of natural enzymes, carbon-based peroxidase-like nanozymes have developed vigorously recent years, which are widely used in biomedical research. In this paper, borocarbonitride nanotubes (BCNNTs) were synthesized via assembly and pyrolysis of small organic molecules achieving boron (B) and nitrogen (N) co-doping in carbon nanotubes. As non-metallic nanozymes, BCNNTs exhibited high peroxidase-like activity and photothermal conversion capability, which were applied to bacterial colorimetric point-of-care testing (POCT) and in situ synergistic inactivation. By BCNNTs functionalized with specific antibody of Staphylococcus aureus, sensitive visible and rapid POCT of Staphylococcus aureus was accomplished. Right after the bacterial assay, the bacterial inactivation proceeded efficiently owing to both the catalytic decomposition of H2O2 and photothermal disinfection induced by BCNNT nanozymes, that eliminated bacterial contamination and further transmission without delay. The multifunctional BCNNT nanozymes possessed high peroxidase-like activity, photothermal property, good biocompatibility and stability, which had great potentials in food safety testing, environmental monitoring, and microbial control and therapy. [ABSTRACT FROM AUTHOR]

Gangliosides are important components of the neuronal cell membrane and play a vital role in the development of neurons and the brain. They participate in neurotransmission and are considered as the structural basis of learning and memory. Gangliosides participate in several and important physiological processes, such as cell differentiation, cell signaling, neuroprotection, nerve regeneration and apoptosis. The stability of ion concentration in excitable cells is particularly important in the maintenance of a steady state of cells and in the regulation of physiological functions. Ion concentration has been found to be related to the ganglioside's regulation in many neurological diseases, and several studies have found that they can stabilize intracellular ion concentration by regulating ion channels, which highlights their important regulatory role in neuronal excitability and synaptic transmission. Gangliosides can influence some forms of ion transport, by directly binding to ion transporters or through indirect binding and activation of transport proteins via appropriate signaling pathways. Therefore, the important and special role of gangliosides in the homeostasis of ion concentration is becoming a hot topic in the field and a theoretical basis in promoting help gangliosides use as key drugs for the treatment of nervous system diseases. [ABSTRACT FROM AUTHOR]

Analgesic-antitumor peptide (AGAP), one of the scorpion toxin polypeptides, has been shown to have an antitumor activity. Recombinant AGAP (rAGAP) was shown to affect the migration and invasion of HepG2 cells via a voltage-gated sodium channel (VGSC) β1 subunit. The VGSC β1 subunit was validated as a cell adhesion molecule (CAM) in human hepatocellular carcinoma (HCC) cell lines. rAGAP suppresses the migration and invasion of HepG2 cells but has no significant effect of human liver HL7702 cells without β1 subunit expression. rAGAP inhibits the migration and invasion of the cells when the VGSC β1 subunit is overexpressed in HL7702 cells. To explain these findings, VGSC β1 subunit messenger RNA (mRNA) and protein levels were measured. The β1 subunit protein level was upregulated in a dose-dependent manner following treatment with rAGAP while there was no significant change in the mRNA level, so rAGAP might be an active component of the VGSC β1 subunit. [ABSTRACT FROM AUTHOR]

The purposes of this study are to investigate the antitumor activities of NSK-01105, a novel sorafenib derivative, in in vitro and in vivo models, and explore the potential mechanisms. The effects of NSK-01105 on proliferation and apoptosis of prostate cancer cells were established by cytotoxicity assays, apoptosis analysis, flow cytometry analysis, and Western blot analysis. Two xenograft tumor models were used to verify the therapeutic effect of NSK-01105 in vivo. NSK-01105 exhibited broad-spectrum antitumor activity, particularly in prostate cancer cells. Characterization of apoptosis morphology was observed, and the percentage of apoptosis-positive cells significantly increased after NSK-01105 treatment for 24 h. Furthermore, a significant increase of the 'sub-G1' population in LNCaP and PC-3 cells after NSK-01105 treatment was determined by cell cycle analysis. Tumor growth was significantly suppressed by once daily oral 30 mg/kg dose of NSK-01105 with the inhibition rates of 63.82 % in LNCaP models and 64.29 % in PC-3 models, respectively. The activation of Raf-1 kinase and epidermal growth factor receptor was downregulated by NSK-01105 at 10 μmol/L. Consequently, the dual inhibitions of Raf/MEK/ERK and PI3K/Akt/mTOR signal pathways were observed by Western blot analysis. Collectively, our results suggest a role of NSK-01105 in treatment for human prostate tumors by inhibiting cell proliferation and inducing apoptosis. NSK-01105 appears to be a promising orally active anticancer drug and deserves further investigation. [ABSTRACT FROM AUTHOR]

Genomic compositions of representatives of thirteen S. dysenteriae serotypes were investigated by performing comparative genomic hybridization (CGH) with microarray containing the whole genomic ORFs (open reading frames, ORFs) of E. coli K12 strain MG1655 and specific ORFs of S. dysenteriae A1 strain Sd51197. The CGH results indicated the genomes of the serotypes contain 2654 conserved ORFs originating from E. coli. However, 219 intrinsic genes of E. coli including those prophage genes, molecular chaperones, synthesis of specific O antigen and so on were absent. Moreover, some specific genes such as type II secretion system associated components, iron transport related genes and some others as well were acquired through horizontal transfer. According to phylogenic trees based on genetic composition, it was demonstrated that A1, A2, A8, A10 were distinct from the other S. dysenteriae serotypes. Our results in this report may provide new insights into the physiological process, pathogenicity and evolution of S. dysenteriae. [ABSTRACT FROM AUTHOR]

A facile colorimetric Pb2+ assay system has been developed based on the visible color change of gold nanoparticles (GNPs) modified with α2-microglobulin (α2M) protein. The α2M protein is a soluble and high-affinity receptor for Pb2+, which is well studied and regarded as the comparable positive control in Pb-binding protein researches. It was obtained through purifying recombinant protein from the expression of recombinant plasmids in Escherichia coli and was attached on GNPs to form GNPs-α2M sensor nanoparticles for detecting Pb2+, which has never been used for sensing Pb2+ in previous studies. When Pb2+ was introduced into the assay system, GNPs-α2M sensor nanoparticles can be triggered aggregation with the color change from pink to blue. The detection system exhibited good selectivity and sensitivity, which was attributed to the receptor specificity of α2M protein. Using this assay system, it can be distinguished 1.00 μM concentration of Pb2+ or more by naked eyes clearly. Furthermore, the UV-Vis absorbance ratio between 620 and 523 nm exhibited linearity relationship with the concentration of Pb2+ from 0.05 to 3 μM in assay system. In this research, GNPs-α2M sensor nanoparticles have highly specific capability to recognize Pb2+. The assay system constituted by GNPs-α2M sensor nanoparticles displays excellent convenience, selectivity, and sensitivity that provide promising potentials for on-site rapid test of Pb2+. [ABSTRACT FROM AUTHOR]