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•A bi-directionally amplified ratiometric electrochemical aptasensor.•Based on RecJf exonuclease and bioconjugate probe.•Wide dynamic range and a remarkable detection limit.•This ...aptasensor was successfully applied for clinical sample analysis.
Alpha-fetoprotein (AFP) is always employed as a biomarker for liver cancer. The detection of AFP with high sensitivity and good anti-interference property is extremely imperative for clinical cancer diagnosis and effective treatment. In this work, a novel bi-directionally amplified ratiometric electrochemical aptasensor based on exonuclease-assisted target recycling and bioconjugate probe was developed for the ultrasensitive detection of AFP. The aptasensor was fabricated by attaching ferrocene-labeled capture probe (Fc-CP) onto electrode surface through the hybridization with thiolated DNA1. The recognition of AFP caused the disassociation of Fc-CP from the DNA1/Fc-CP duplex, and further triggered the cleavage process of RecJf exonuclease and recycling of AFP. As a result, numerous Fc labels were released, accompanied by plenty exposed DNA1 on the electrode surface for the hybridization with bioconjugate probe containing vast methylene blue (MB) molecules. This strategy significantly amplified the decrease of Fc signal and the increase of MB signal, finally achieving a wide detection range of seven orders of magnitude and an ultralow AFP detection limit down to 269.4 ag/mL. The anti-interference property of the aptasensor was verified by analyzing clinical human serum samples. This aptasensor is promising for the development of reliable electrochemical devices for point-of-care diagnosis.
Surface-enhanced Raman scattering method for sensitive and selective monitoring of Pb2+ was realized by in situ regulation the nanoarchitecture of gold nanoparticles/reduced graphene oxide through ...Pb2+-enhanced gold dissolution reaction. Display omitted
In this work, the colloid of Au nanoparticles (AuNPs)/reduced graphene oxide (rGO) was synthesized by growth AuNPs on rGO via the reduction of HAuCl4 on graphene oxide (GO) nanosheets. The nanoarchitecture of the colloid could be controllably regulated through in-situ Pb2+-enhanced gold leaching reaction, which made the colloid be a flexible surface-enhanced Raman scattering (SERS) platform for Pb2+ detection. Upon the addition of Pb2+, the Raman signal of graphene underwent significant descent due to the decrease of the amount of the “hot spots”, which was originated from Pb2+-accelerated dissolution of AuNPs on the graphene surface in the present of thiosulfate (S2O32−). Based on the change of SERS signal through in situ regulation the nanoarchitecture of the colloid, a sensitive and selective strategy for Pb2+ measurement was developed with a linear range from 5nM to 4μM as well as a low detection limit of 1nM. Furthermore, the SERS-based method was applied for the determination of Pb2+ in water samples with satisfactory results.
Abscisic acid (ABA) plays an essential role in seed germination. In this study, we demonstrate that one SNF1-RELATED PROTEIN KINASE3-type protein kinase, SOS2-LIKE PROTEIN KINASE5 (PKS5), is involved ...in ABA signal transduction via the phosphorylation of an interacting protein, ABSCISIC ACID-INSENSITIVE5 (ABI5). We found thatpks5-3andpks5-4, two previously identified PKS5 superactive kinase mutants with point mutations in the PKS5 FISL/NAF (a conserved peptide that is necessary for interaction with SOS3 or SOS3-LIKE CALCIUM BINDING PROTEINs) motif and the kinase domain, respectively, are hypersensitive to ABA during seed germination. PKS5 was found to interact with ABI5 in yeast (Saccharomyces cerevisiae), and this interaction was further confirmed in planta using bimolecular fluorescence complementation. Genetic studies revealed thatABI5is epistatic toPKS5. PKS5 phosphorylates a serine (Ser) residue at position 42 in ABI5 and regulates ABA-responsive gene expression. This phosphorylation was induced by ABA in vivo and transactivated ABI5. Expression of ABI5, in which Ser-42 was mutated to alanine, could not fully rescue the ABA-insensitive phenotypes of theabi5-8andpks5-4abi5-8mutants. In contrast, mutating Ser-42 to aspartate rescued the ABA insensitivity of these mutants. These data demonstrate that PKS5-mediated phosphorylation of ABI5 at Ser-42 is critical for the ABA regulation of seed germination and gene expression in Arabidopsis (Arabidopsis thaliana).
Basic helix-loop-helix (bHLH) transcription factors (TFs) are one of the largest gene families in plants. They regulate gene expression through interactions with specific motifs in target genes. bHLH ...TFs are not only universally involved in plant growth but also play an important role in plant responses to abiotic stress. However, most members of this family have not been functionally characterized.
Here, we characterized the function of a bHLH TF in the peanut, AhHLH112, in response to drought stress. AhHLH112 is localized in the nucleus and it was induced by drought stress. The overexpression of this gene improves the drought tolerance of transgenic plants both in seedling and adult stages. Compared to wild-type plants, the transgenic plants accumulated less reactive oxygen species (ROS), accompanied by increased activity and transcript levels of antioxidant enzymes (superoxide dismutase, peroxidase and catalase). In addition, the WT plants demonstrated higher MDA concentration levels and higher water loss rate than the transgenic plants under drought treatment. The Yeast one-hybrid result also demonstrates that AhbHLH112 directly and specifically binds to and activates the promoter of the peroxidase (POD) gene. Besides, overexpression of AhHLH112 improved ABA level under drought condition, and elevated the expression of genes associated with ABA biosynthesis and ABA responding, including AtNCED3 and AtRD29A.
Drawing on the results of our experiments, we propose that, by improving ROS-scavenging ability, at least in part through the regulation of POD -mediated H
O
homeostasis, and possibly participates in ABA-dependent stress-responding pathway, AhbHLH112 acts as a positive factor in drought stress tolerance.
Workplace stressors were identified to have critical impacts on employee creativity. However, little is known about how and when involuntary citizenship behavior i.e., compulsory citizenship behavior ...(CCB)-induced stress might exert an influence on employee creativity. To fill this knowledge gap, the present study firstly develops a moderated mediation model to investigate the CCB–employee creativity association as well as the underlying mechanism and contextual condition of this relationship. By integrating social cognitive theory such as self-efficacy theory and conservation of resources (COR) theory, we propose that CCB predicts employee creativity through the mediating role of creative self-efficacy (CSE), with the individual characteristics (i.e., personality traits) of negative affect acting as a boundary condition. Using two-wave time-lagged survey data collected from a sample of 251 frontline employees in 10 manufacturing firms in Southern China, the results show that: (a) CSE mediates the negative relationship between CCB and employee creativity; (b) negative affect moderates the relationship between CCB and CSE; (c) negative affect moderates the indirect influence of CCB on employee creativity through CSE. As the level of negative affect rises, this indirect relationship is stronger. Finally, important theoretical and managerial implications and promising avenues for future research are addressed.
The epididymis is divided into three regions including the caput, corpus and cauda. Gene expression profiles in different regions indicate the different functions of epididymis which are crucial for ...sperm maturation. In this study, three one-year-old rams was used as the experimental animal. Transcriptome sequencing technology was used to sequence mRNA in the caput, corpus and cauda of the epididymis. Based on the spatiotemporal-specific expression pattern in the epididymis, the mRNA expression profiles of the three parts of the epididymis were analysed. Region-specifically expressed genes were analysed by GO and KEGG analyses to screen the key genes involved in sheep sperm maturation. We obtained 129, 54 and 99 specifically expressed genes in the caput, corpus and cauda, respectively. And twenty specific expressed genes related to sperm maturation were used to construct functional networks. The heatmap showed that 6 genes of LCN protein family were highly expressed in the head of epididymis of sheep. We infer that sperm maturation is gradual in the epididymis and that there are significant differences in epididymal gene expression patterns between different species. This provides a data resource for analysing the regulatory mechanism of epididymis genes related to sperm maturation in rams.
ALK-positive anaplastic large-cell lymphoma (ALK + ALCL) is characterized by expression of ALK and CD30. The current World Health Organization (WHO) classification recognizes five morphologic ...patterns: common, small-cell, lymphohistiocytic, Hodgkin-like, and composite. There are few reports about the morphologic transformation of ALK + ALCL. Today, we report an intriguing case of presumed transformation from common-pattern to composite-pattern (lymphohistiocytic and small-cell pattern) ALK + ALCL, with CD30 expression changing from positive to negative. This case expands understanding of morphologic transformation between different subtypes of ALK + ALCL and highlights common diagnostic pitfalls, including atypical morphology and negative CD30. Morphologic transformation of ALK + ALCL should be assigned importance, and comprehensive clinical history, histologic and immunophenotypic evaluation are vital to rendering the correct diagnosis of ALK + ALCL.
Tibetan cashmere goats are served as a valuable model for high altitude adaptation and hypoxia complications related studies, while the cashmere produced by these goats is an important source of ...income for the herders. The aim of this study was to investigate the differences in protein abundance underlying the fine (average 12.20 ± 0.03 μm of mean fiber diameter) and coarse cashmere (average 14.67 ± 0.05 μm of mean fiber diameter) producing by Tibetan cashmere goats. We systematically investigated the genetic determinants of fiber diameter by integrated analysis with proteomic and transcriptomic datasets from skin tissues of Tibetan cashmere goats.
We identified 1980 proteins using a label-free proteomics approach. They were annotated to three different databases, while 1730 proteins were mapped to the original protein coding genes (PCGs) of the transcriptomic study. Comparative analyses of cashmere with extremely fine vs. coarse phenotypes yielded 29 differentially expressed proteins (DEPs), for instance, APOH, GANAB, AEBP1, CP, CPB2, GPR142, VTN, IMPA1, CTSZ, GLB1, and HMCN1. Functional enrichment analysis of these DEPs revealed their involvement in oxidation-reduction process, cell redox homeostasis, metabolic, PI3K-Akt, MAPK, and Wnt signaling pathways. Transcription factors enrichment analysis revealed the proteins mainly belong to NF-YB family, HMG family, CSD family. We further validated the protein abundance of four DEPs (GC, VTN, AEBP1, and GPR142) through western blot, and considered they were the most potential candidate genes for cashmere traits in Tibetan cashmere goats.
These analyses indicated that the major biological variations underlying the difference of cashmere fiber diameter in Tibetan cashmere goats were attributed to the inherent adaptations related to metabolic, hypoxic, and stress response differences. This study provided novel insights into the breeding strategies for cashmere traits and enhance the understanding of the biological and genetic mechanisms of cashmere traits in Tibetan cashmere goats.
The adaptive evolution of plateau indigenous animals is a current research focus. However, phenotypic adaptation is complex and may involve the interactions between multiple genes or pathways, many ...of which remain unclear. As a kind of livestock with important economic value, cashmere goat has a high ability of plateau adaptation, which provides us with good materials for studying the molecular regulation mechanism of animal plateau adaptation.
In this study, 32 Jiangnan (J) and 32 Tibetan (T) cashmere goats were sequenced at an average of 10. Phylogenetic, population structure, and linkage disequilibrium analyses showed that natural selection or domestication has resulted in obvious differences in genome structure between the two breeds. Subsequently, 553 J vs. T and 608 T vs. J potential selected genes (PSGs) were screened. These PSGs showed potential relationships with various phenotypes, including myocardial development and activity (LOC106502520, ATP2A2, LOC102181869, LOC106502520, MYL2, ISL1, and LOC102181869 genes), pigmentation (MITF and KITLG genes), hair follicles/hair growth (YAP1, POGLUT1, AAK1, HES1, WNT1, PRKAA1, TNKS, WNT5A, VAX2, RSPO4, CSNK1G1, PHLPP2, CHRM2, PDGFRB, PRKAA1, MAP2K1, IRS1, LPAR1, PTEN, PRLR, IBSP, CCNE2, CHAD, ITGB7, TEK, JAK2, and FGF21 genes), and carcinogenesis (UBE2R2, PIGU, DIABLO, NOL4L, STK3, MAP4, ADGRG1, CDC25A, DSG3, LEPR, PRKAA1, IKBKB, and ABCG2 genes). Phenotypic analysis showed that Tibetan cashmere goats has finer cashmere than Jiangnan cashmere goats, which may allow cashmere goats to better adapt to the cold environment in the Tibetan plateau. Meanwhile, KRTs and KAPs expression in Jiangnan cashmere goat skin was significantly lower than in Tibetan cashmere goat.
The mutations in these PSGs maybe closely related to the plateau adaptation ability of cashmere goats. In addition, the expression differences of KRTs and KAPs may directly determine phenotypic differences in cashmere fineness between the two breeds. In conclusion, this study provide a reference for further studying plateau adaptive mechanism in animals and goat breeding.
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