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MicroRNAs (miRNAs) are commonly used as biomarkers for the diagnosis of tumors. Since miRNA expression is strongly correlated to carcinogenesis, the detection of miRNA concentration in cells would be valuable for the diagnosis and evaluation of tumors. In this study, we proposed a system using two strands of DNA, one modified by a phosphate group at the 5' end, called Cap, and the other with a hairpin structure, called HP. The Cap chain could open the hairpin structure of HP and expose the sequences rich in G bases to form the G-quadruplex structure. Then, a strong fluorescence signal was emitted in the presence of N-methyl mesoporphyrin IX (NMM). However, with the addition of miRNA-21, Cap hybridized with it to form double chains, which were then cleaved by the digestion of lambda exonuclease, resulting in a weak fluorescent signal. The proposed method could detect miRNA-21 at a concentration of 1.4 pM with a broad dynamic linear range from 5 pM to 5 nM.

As a representative biochemical indicator, alkaline phosphatase (ALP) is of great importance in indicating and diagnosing clinical diseases. Herein, we developed a signal-on fluorescence sensing method for sensitive ALP activity detection based on the enzyme-assisted target recycling (EATR) technique. In this method, a two-step signal amplification process is designed. In the presence of ALP, the 3' phosphate group of an ss-DNA is removed explicitly by ALP, thus releasing free 3'-OH. Terminal deoxynucleotidyl transferase (TdT) can subsequently extend this substrate to generate poly(A) tails, converting the trace-level ALP information into multiple sequences and achieving the first-time amplification. A poly(T) Taqman probe labeled with FAM and BHQ1 provides the second one under the assistance of T7 exonuclease (T7 Exo) through alternate hybridization and degradation of ds-DNA regions. The previously quenched fluorescence is recovered due to the departure of FAM/BHQ1 during the cleavage of T7 Exo. Thus, taking advantage of template-free TdT-mediated polymerization and T7 Exo-based EATR, this strategy shows a sensitive LOD at 0.0074 U/L (S/N = 3) and a linear range of 0.01-8 U/L between ALP concentration and fluorescence intensity. To further verify the specificity and accuracy in practical application, we challenged it in a set of co-existing interference and biological environments and have gained satisfying results. The proposed method successfully quantified the ALP levels in clinical human serum samples, suggesting its applicability in practical application. Moreover, we have used this method to investigate the inhibition effects of Na

Alkaline phosphatase is one of the most important tool enzymes and diseases indicator, monitoring ALP activity with convenient, precise, efficient and sensitive methods plays a fundamental role in modern life and healthcare industries. In this study, we described a novel method for ALP analysis based on Pb

Nanodrug carrier-based cancer therapy has been actively developed in the past decades. The main challenges faced by nanodrug carriers include poor drug loading capacity, rapid clearance from blood circulation, and low antitumor efficiency. In this work, a new type of antineoplastic agents, F-RGID, were developed using a two-dimensional graphene oxide (GO) with an incorporated photosensitizer (Indocyanine Green, ICG) and a chemotherapeutic drug (Doxorubicin, DOX) as the internally wrapped nanoparticles, and the RBC membrane (RM) inserted with the targeting molecule (folic acid, F) as a shell. The endogenous nature of RM confers F-RGID excellent biocompatibility and the ability to evade from clearance by the reticuloendothelial system (RES). In addition, F-RGID is decorated with folic acid for selective recognition of tumor cells via a lipid-insertion approach. Another salient feature of the antineoplastic platform is the combination of photothermal-chemotherapy with ICG and DOX. In vitro and in vivo experiments revealed that F-RGID could provide a bionic nanoplatform for tumor-targeted photothermal-chemotherapy in clinic.

This study describes a novel quencher-free fluorescent method for ochratoxin A (OTA) detection based on the photoinduced electron transfer (PIET) between guanine and fluorophore. In the absence of OTA, carboxyfluorescein (FAM)-labeled aptamer can partly hybridize with the complementary strand of OTA aptamer (OTA-cAPT), which contains four guanines at its 3&prime, end. As a result, the fluorescence of FAM is quenched due to PIET and stacked guanines. In the presence of OTA, FAM-labeled OTA aptamer can bind specifically to OTA, and thereby the high fluorescence intensity of the dye can be maintained. Under the optimal conditions, the method had a detection limit of 1.3 nM. In addition, the method we proposed is highly sensitive and specific for OTA. Furthermore, the method was proven to be reliable based on its successful application in the detection of OTA in red wine samples. Therefore, this promising, facile, and quencher-free method may be applied to detect other toxins by using other appropriate aptamers.

In this work, we developed a facile fluorescence method for quantitative detection of human serum albumin (HSA) based on the inhibition of poly(thymine) (poly T)-templated copper nanoparticles (CuNPs) in the presence of HSA. Under normal circumstances, poly T-templated CuNPs can display strong fluorescence with excitation/emission peaks at 340/610 nm. However, in the presence of HSA, it will absorb cupric ion, which will prevent the formation of CuNPs. As a result, the fluorescence intensity will become obviously lower in the presence of HSA. The analyte HSA concentration had a proportional linear relationship with the fluorescence intensity of CuNPs. The detection limit for HSA was 8.2 × 10−8 mol·L−1. Furthermore, it was also successfully employed to determine HSA in biological samples. Thus, this method has potential applications in point-of-care medical diagnosis and biomedical research.

Lipopolysaccharide induced TNFα factor (LITAF) is an important transcription factor responsible for regulation of tumor necrosis factor α. In this study, a novel litaf gene (designated as Malitaf) was identified and characterized from blunt snout bream, Megalobrama amblycephala. The full-length cDNA of Malitaf was of 956 bp, encoding a polypeptide of 161 amino acids with high similarity to other known LITAFs. A phylogenetic tree also showed that Malitaf significantly clustered with those of other teleost, indicating that Malitaf was a new member of fish LITAF family. The putative maLITAF protein possessed a highly conserved LITAF domain with two CXXC motifs. The mRNA transcripts of Malitaf were detected in all examined tissues of healthy M. amblycephala, including kidney, head kidney, muscle, liver, spleen, gill, and heart, and with the highest expression in immune organs: spleen and head kidney. The expression level of Malitaf in spleen was rapidly up-regulated and peaked (1.29-fold, p < 0.05) at 2 h after lipopolysaccharide (LPS) stimulation. Followed the stimulation of Malitaf, Matnfα transcriptional level was also transiently induced to a high level (51.74-fold, p < 0.001) at 4 h after LPS stimulation. Taken together, we have identified a putative fish LITAF ortholog, which was a constitutive and inducible immune response gene involved in M. amblycephala innate immunity during the course of a pathogenic infection.

Toll-like receptors (TLRs) are central players in the innate immune system in response to a wide range of pathogen infection. Among various TLRs, TLR4 plays a key role in recognition of bacterial lipopolysaccharides (LPS). In the present study, we identified and characterized a novel TLR4 homologue (maTLR4b) in blunt snout bream (Megalobrama amblycephala) which was significantly distinct from previously reported M. amblycephala TLR4 (tentatively named maTLR4a). The results showed that the complete cDNA sequence of maTLR4b was 3261 bp with an open reading frame encoding a polypeptide of 820 amino acids, and that its genomic sequence was 3793 bp, which had 3 exons. Structurally, the deduced maTLR4b protein showed a typical TLR domain architecture, including a signal peptide, eight leucine-rich repeats (LRRs) in the extracellular region, a transmembrane domain, and a Toll-Interleukin 1 receptor (TIR) domain in the cytoplasmic region. Phylogenetic analysis revealed that all TLR4s from teleost fish formed a monophyletic clade. Both maTLR4a and maTLR4b were divided into two distinct branches, and showed the highest level of similarity with the grass carp TLR4.2 and TLR4.4 homologue, respectively. MaTLR4b was constitutively expressed in all healthy tissues tested although at different levels. After LPS stimulation, the expression levels were significantly up-regulated in spleen, and peaked at 4 h between maTLR4a and maTLR4b, but with a distinct and complementary expression patterns. Taken together, these results suggested that maTLR4b is indeed a functional homologue of TLR4 in other species, which may play vital role in innate immune.

Autism is a heterogeneous childhood neurodevelopmental disorder that is characterised by deficits in verbal communication, impaired social interactions, restricted interests and repetitive behaviours. Using an Illumina HumanCNV370-Quad BeadChip, we identified two Han Chinese individuals with autism and large duplications (~1.6 Mb and ~2.4 Mb) disrupting the same CNTN4 gene. CNTN4 encodes a protein that functions as a cell-adhesion molecule and may play an essential role in the formation of axon connections in the developing nervous system. The disruption of this gene has been reported to be the cause of the 3p deletion syndrome and also a possible susceptibility factor for autism spectrum disorders (ASDs). Our results suggest that rare copy number variations (CNVs) in CNTN4 may also influence autism susceptibility in Asian populations. Interestingly, a comparison of the clinical phenotypes between the two subjects revealed that the subject with the 2.4 Mb CNV (involving several other genes) presented with a more severe phenotype than the subject with the 1.6 Mb CNV (disrupting only CNTN4 and CNTN6). This suggests that other genes in the nearby region may contribute to the pathogenesis.

Purpose To investigate the etiology in a family with autosomal-dominant congenital simple microphthalmia of Chinese origin. Methods A whole-genome scan was performed by using 382 microsatellite DNA markers after the exclusion of reported candidates linked to microphthalmia. Additional fluorescent markers were genotyped for fine mapping. To find out the novel predisposing gene, 14 candidate genes including CRYBA1 and NCOR1 were selected to screen for the mutation by the PCR direct-sequencing method. Genome-wide single-nucleotide polymorphism (SNP) genotyping was performed to find out the pathogenetic copy number variation, as well. Results The most statistically significant linkage results were obtained at D17S1824 (maximum LOD score, 4.97, at recombination fraction 0.00). Haplotype analyses supported the location of the disease-causing gene to a 21.57-cM interval between loci D17S900 and D17S1872 of chromosome 17, region p12-q12. However, no mutation or CNV (copy number variation) was identified to be responsible for the microphthalmia phenotype of this pedigree. Conclusions A novel suggestive linkage locus for congenital microphthalmia was detected in a Chinese family. This linkage region provides a target for susceptibility gene identification.