The sensitive and label-free detection of multiple biomarkers on a single electrode by photoelectrochemical (PEC) sensors based on light addressing strategies is very attractive for developing ...portable and high-throughput biosensing systems. The essential prerequisite of this proposal is the employment of uniform photovoltaic material modified electrodes with high conversion efficiency. Herein, a novel two-step constant potential deposition method for the rapid fabrication of bismuth sulfide film modified ITO electrodes (Bi2S3/ITO) was established. The produced Bi2S3/ITO, with excellent uniformity and high conversion efficiency in visible light ranges, was further modified with gold nanoparticles (AuNPs) and then divided into separated identical sensing zones by insulative paints. The adsorption-based immobilization of antibodies of three tumor markers, i.e., a-fetoprotein (AFP), carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9), onto different sensing zones of the electrode and the further blocking with BSA established a label-free and light-addressable PEC sensor (LF-LAPECS), which can achieve the rapid and sensitive detection of these biomarkers with wide linear ranges, low detection limits and self-calibration ability. Moreover, the detection throughput can be conveniently improved by enlarging the size of the substrate electrode and increasing the number of separated sensing zones. The present work thus demonstrates the promising applications of PEC techniques for developing sensitive, time-saving, cost-effective and high-throughput biosensing methods.
•A simple deposition method for producing uniform Bi2S3 films was established.•A label-free and light-addressable PEC sensor was constructed on the Bi2S3 films.•The sensor can achieve sensitive multiplexed detection on a single electrode.•The sensor possesses properties of high throughput and self-calibration ability.
Mutations in the proline-rich transmembrane protein 2 （PRRT2） are associated with paroxysmal kinesigenic dys- kinesia （PKD） and several other paroxysmal neurological diseases, but the PRRT2 function ...and pathogenic mecha- nisms remain largely obscure. Here we show that PRRT2 is a presynaptic protein that interacts with components of the SNARE complex and downregulates its formation. Loss-of-function mutant mice showed PKD-like phenotypes triggered by generalized seizures, hyperthermia, or optogenetic stimulation of the cerebellum. Mutant mice with spe- cific PRRT2 deletion in cerebellar granule cells （GCs） recapitulate the behavioral phenotypes seen in Prrt2-null mice. Furthermore, recording made in cerebellar slices showed that optogenetic stimulation of GCs results in transient elevation followed by suppression of Purkinje cell firing. The anticonvulsant drug carbamazepine used in PKD treat- ment also relieved PKD-like behaviors in mutant mice. Together, our findings identify PRRT2 as a novel regulator of the SNARE complex and provide a circuit mechanism underlying the PRRT2-related behaviors.
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•The interfacial redox reaction between NiOx and perovskite is obstructed.•SaC-100 is developed as a modifier layer in NiOx-based perovskite solar cells.•SaC-100 can efficiently ...reduce the open-circuit voltage loss of device.•SaC-100 can inhibit perovskite decomposition ascribed from interfacial reaction.
In NiOx-based perovskite solar cells (PVSCs), the interfacial redox reaction between Ni3+ (on the surface of NiOx) and A-site cation salt (MAI in perovskite precursor solution) is invariably ignored. This adverse reaction will generate PbI2-rich hole extraction barriers at the NiOx-perovskite interface, which limits hole transmission and increases charge recombination, thus resulting in open-circuit voltage (Voc) loss. Furthermore, it will accelerate perovskite degradation by deprotonating the precursor amine and oxidizing iodide to interstitial iodine, which induces the severe instability of devices. Herein, a physical separation strategy by introducing a modifier layer to obstruct the detrimental reaction is explored. The results demonstrate that the trimethylolpropane tris(2-methyl-1-aziridinepropionate) (SaC-100) depositing onto NiOx can suppress the reaction between Ni3+ and MAI to endow the improvement of conductivity and reduction of interfacial defects, thus reducing Voc loss and enhancing device stability. Moreover, the interfacial energy level alignment and the morphology of perovskite are also optimized. As a result, the PVSCs device based on NiOx/SaC-100 presents the best power conversion efficiency (PCE) of 20.21% with a superior Voc value of 1.12 V. Furthermore, the device shows better light and thermal stability because of the hindering effect and defect passivation effect of SaC-100.
Neuroinflammation and Alzheimer’s-related pathology play essential roles in postoperative cognitive dysfunction (POCD). High-mobility group box 1 (HMGB1) is well known as a pivotal mediator in ...neuroinflammation, and its associations with Alzheimer’s-related pathology and POCD have been also revealed. Glycyrrhizin is a nature inhibitor of HMGB1 and is reported with neuroprotective effects through oral administration. Therefore, the present study aims to test the hypothesis that the oral pretreatment of glycyrrhizin prevents POCD by inhibiting HMGB1-induced neuroinflammation and Alzheimer’s-related pathology in aged mice. Aged male C57BL/6 mice were subjected to the splenectomy surgery under general anesthesia and the oral pretreatment of glycyrrhizin. The postoperative cognitive changes were evaluated by using Morris water maze (MWM) test. The protein expressions of HMGB1, TLR4, NF-κB, p-Tau, and pro-inflammatory cytokines were determined by Western blot assay. The hippocampal level of β-amyloid (Aβ) was assessed by ELISA assay. We found that the oral pretreatment of glycyrrhizin inhibited HMGB1 cytosolic expression, increased the PSD-95 protein expression, and attenuated the severity of postoperative memory impairment, as indicated by the shorter swimming latency and distance in MWM trials when compared with the mice subjected to the surgery alone. Additionally, the pretreatment of glycyrrhizin reduced the postoperative neuroinflammation (production of pro-inflammatory cytokines including IL-1β, TNF-α, and IL-6 as well as NF-κB nuclear expression) and Alzheimer’s-related pathology (Tau phosphorylation at the site of AT-8 and Ser396 as well as Aβ40 and 42 concentrations) in the hippocampus of the aged mice undergoing splenectomy surgery. In conclusion, our results suggest that the oral pretreatment of glycyrrhizin can prevent the postoperative cognitive impairment by reducing neuroinflammation and Alzheimer’s-related pathology in the hippocampus of aged mice via HMGB1 inhibition.
Enzyme promiscuity is critical to the acquisition of evolutionary plasticity in cells and can be recruited for high‐value chemical synthesis or xenobiotic degradation. The molecular determinants of ...substrate ambiguity are essential to this activity; however, these details remain unknown. Here, we performed the directed evolution of a prolidase to enhance its initially weak paraoxonase activity. The in vitro evolution led to an unexpected 1,000,000‐fold switch in substrate selectivity, with a 30‐fold increase in paraoxon hydrolysis and 40,000‐fold decrease in peptide hydrolysis. Structural and in silico analyses revealed enlarged catalytic cavities and substrate repositioning as responsible for rapid catalytic transitions between distinct chemical reactions.
Yang and colleagues perform laboratory evolution of a bacterial prolidase to enhance its initially promiscuous paraoxonase activity, leading to a substrate selectivity switch of >106‐fold and expanded specificity toward organophosphorus compounds. Moreover, the authors reveal reshaped active cavity perturbs substrate positioning to facilitate rapid transition between native and promiscuous catalysis by structural and in silico analyses.
The aberrant activation of sonic hedgehog (SHH) pathway contributes to initiation and progression of various malignancies. However, the roles and underlying mechanisms of SHH signaling pathway in ...invasion and metastasis of liver cancer have not been well understood. In this study, we found that SHH signaling was activated and correlated with invasion and metastasis in hepatocellular carcinoma (HCC). Enhanced SHH signaling by recombinant human SHH N-terminal peptide (rSHH-N) promoted hepatoma cell adhesion, migration and invasion, whereas blockade of SHH signaling with SHH neutralizing antibody or cyclopamine suppressed hepatoma cell adhesion, migration and invasion. Furthermore, matrix metalloproteinase (MMP)-2 and MMP-9 expressions and activities were upregulated and downregulated by rSHH-N and SHH signaling inhibitor, respectively. The rSHH-N-mediated hepatoma cell migration and invasion was blocked by MMP-specific inhibitors or neutralizing antibodies to MMP-2 and MMP-9. In addition, phosphorylations of AKT and focal adhesion kinase (FAK) were increased and decreased by rSHH-N and SHH signaling inhibitor, respectively. Further investigations showed that activation of AKT and FAK were required for rSHH-N-mediated upregulation of MMP-2 and MMP-9, cell migration and invasion. Finally, we found that SHH protein expression was positively correlated with phosphorylatd FAK Tyr397, phosphorylatd AKT Ser473, MMP-2 and MMP-9 protein expressions in HCC samples. Taken together, our findings suggest that SHH pathway induces cell migration and invasion through FAK/AKT signaling-mediated MMP-2 and MMP-9 production and activation in liver cancer.
Aim: Recent studies have underlined causative links between microRNA (miRNA) deregulation and cancer development. However, the relevance of abnormally expressed miRNA to tumor biology has not been ...well understood in hepatocellular carcinoma (HCC).
Methods: A bead‐based miRNA expression profiling method was performed on 20 pairs of surgically removed HCC and adjacent non‐tumorous tissue (NT). Special miR‐338 downregulations and miR‐338 associated with clinical characteristics was validated in an extended samples set of 36 paired HCC and adjacent non‐tumorous liver tissues by real‐time reverse transcription polymerase chain reaction (RT‐PCR) analysis.
Results: Out of our bead‐based microarray data, 12 upregulated and 19 downregulated miRNA were found to be associated with HCC. Further characterization of miRNA‐338, in which 20 pairs of the samples were clustered clearly into two groups according to expression of miR‐338, revealed that the level of miR‐338 expression can be associated with clinical aggressiveness, such as, tumor size, tumor–node–metastasis stage, vascular invasion and intrahepatic metastasis. These results were validated by real‐time RT‐PCR analysis.
Conclusion: Our study suggests that miRNA expression could have relevance to the clinical behavior of HCC and that the bead‐based miRNA expression profiling method might be a suitable system to assay miRNA expression in large‐scale diagnostic trails.
Aim: To investigate the status of Phosphatidylinositol 3‐kinase (PI3K)/PTEN/AKT/mammalian target of rapamycin (mTOR) pathway and its correlation with clinicopathological features and matrix ...metalloproteinase‐2, ‐9 (MMP‐2, 9) in human hepatocellular carcinoma (HCC).
Methods: PTEN, Phosphorylated AKT (p‐AKT), Phosphorylated mTOR (p‐mTOR), MMP‐2, MMP‐9 and Ki‐67 expression levels were evaluated by immunohistochemistry on tissue microarrays containing 200 HCCs with paired adjacent non‐cancerous liver tissues. PTEN, MMP‐2 and MMP‐9 mRNA levels were determined by real‐time RT‐PCR in 36 HCCs. The relationships between PI3K/PTEN/AKT/mTOR pathway and clinicopathological factors and MMP‐2, 9 were analyzed in HCC.
Results: In HCC, PTEN loss and overexpression of p‐AKT and p‐mTOR were associated with tumor grade, intrahepatic metastasis, vascular invasion, TNM stage and high Ki‐67 labeling index (P < 0.05). PTEN loss was correlated with p‐AKT, p‐mTOR and MMP‐9 overexpression. Furthermore, PTEN and MMP‐2, 9 mRNA levels were down‐regulated and up‐regulated in HCC compared with paired non‐cancerous liver tissues, respectively (P < 0.01). PTEN, MMP‐2 and MMP‐9 mRNA levels were correlated with tumor stage and metastasis. There was an inverse correlation between PTEN and MMP‐9 mRNA expression. However, PI3K/PTEN/AKT/mTOR pathway was not correlated with MMP‐2.
Conclusions: PI3K/PTEN/AKT/mTOR pathway, which is activated in HCC, is involved in invasion and metastasis through up‐regulating MMP‐9 in HCC.
Transforming growth factor β (TGF-β) signaling controls diverse cellular processes during embryogenesis as well as in mature tissues of multicellular animals. Here we carried out a comprehensive ...analysis of TGF-β pathway members in 24 representative animal species. The appearance of the TGF-β pathway was intrinsically linked to the emergence of metazoan. The total number of TGF-β ligands, receptors, and smads changed slightly in all invertebrates and jawless vertebrates analyzed. In contrast, expansion of the pathway members, especially ligands, was observed in jawed vertebrates most likely due to the second round of whole genome duplication (2R) and additional rounds in teleosts. Duplications of
,
,
,
and
, which were resulted from 2R, were first isolated. Type II receptors may be originated from the
-like ancestor. Interestingly,
was not identified in Chimaeriformes and Cypriniformes even though they had the ligand
. Based on transcriptome data, TGF-β ligands exhibited a tissue-specific expression especially in the heart and gonads. However, most receptors and smads were expressed in multiple tissues indicating they were shared by different ligands. Spatial and temporal expression profiles of 8 genes in gonads of different developmental stages provided a fundamental clue for understanding their important roles in sex determination and reproduction. Taken together, our findings provided a global insight into the phylogeny and expression patterns of the TGF-β pathway genes, and hence contribute to the greater understanding of their biological roles in the organism especially in teleosts.
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