Search

Molecular imprinting (MI) technology has been used in electrochemical analysis technology because of its unique selectivity and specificity. In this work, an electrochemical sensor based on in-situ inorganic MI-Au-MoO3/graphene for bisphenol A (BPA) analysis is designed, where MI-MoO3 is hybridized with graphene nanosheets and Au nanoparticles, and BPA is acted as the temple molecular. Differential pulse voltammetry (DPV) was used to evaluate the sensing performance of the MI-Au-MoO3/rGO sensor toward BPA determination and it is about 2.0 times that of NI-Au-MoO3/rGO. The as-constructed sensor presents a wide linear range from 0.01 to 106.04 μM and a low limit of detection of 0.003 μM. It also displays outstanding stability and repeatability up to 20 days, and can be used to analyze the content of BPA in dust leachate and plastic bottle. This sensor offers a promising strategy for environment pollution and food analysis via MI technology.

NiMoO4 nanorods (NRs) were successfully fabricated on Ni foam with robust adhesion via a simple and cost-effective hydrothermal treatment, followed by a calcined process. In a three-electrode configuration with 3 mol L−1 KOH aqueous solution. The NiMoO4 NRs supported on Ni foam as working electrodes achieve a high specific capacity of 1320 C g−1 at a charge and discharge current density of 2 mA cm−2, and a desirable rate capability (884 C g−1 even at 10 mA cm−2) and a superior cycling ability with 88% capacity retention after 4000 cycles at 10 mA cm−2. To enhance the energy density and enlarge the voltage window, the aqueous hybrid supercapacitor has subsequently been constructed by employing the NiMoO4 and activated carbon electrodes as positive and negative electrodes, respectively, which delivered a high energy density of 52 Wh kg−1 at a power density of 725 W kg−1. Impressively, the device indicates a long-term cycling stability with capacitance retention of 123% even after 9000 cycles in aa safe voltage range from 0 V to 1.45 V. These results definitely imply the promising prospect of NiMoO4 NR electrodes for application in supercapacitors.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has increased in incidence and prevalence in recent decades. Both clinical and animal studies are critical for understanding the pathogenesis of this disease. Dextran sodium sulfate (DSS)-induced colitis is a frequently used animal model of IBD, but the underlying mechanism of the model remains incompletely understood. In this study, we found that NOD-like receptor family pyrin containing 3 (NLRP3) depletion markedly mitigated DSS-induced colitis and was accompanied by decreased activation of the inflammasome in the colons of mice. However, in vitro assays showed that DSS did not directly trigger but instead potentiated NLRP3 inflammasome assembly in macrophages in response to suboptimal ATP or nigericin stimulation. Mechanistically, DSS potentiated NLRP3 inflammasome activation in macrophages by augmenting KCa3.1-mediated potassium ion (K

In this work, we report a high-performance photodetector based on perovskite CH3NH3PbBr3 quantum dots (QDs) films with a configuration of Au/CH3NH3PbBr3 QDs-Al2O3-indium tin oxide/Au as a bioinspired photoelectric synapse. The uniform CH3NH3PbBr3 QDs thin film is fabricated by a electrodepositing QDs solution and exhibits favorable long-term stability at ambient. By inserting an Al2O3 film, the dark current of the QDs film photodetectors is significantly suppressed as a result of the blocking effect, accompanied by the enhanced ON/OFF ratio. Furthermore, the optimal photodetector is utilized as a photoelectric synapse. Through modulating the light pulse stimuli, some underlying synaptic functions, including paired-pulse facilitation, axon-multi-synapses network function, and the transformation from short-term plasticity to long-term plasticity, are flexibly emulated on a single photoelectric synapse. These remarkable results are promising for building hardware units with neuromorphic architecture to mimic the human brain functionalities.

Due to their highly porous structures, metal organic framework materials are widely used in analytic areas. In this paper, Cr-metal organic framework (MIL-101(Cr)) modified electrode was prepared and then was used as electrochemical sensor for the detection of bisphenol A (BPA). By using one kind of surfactant of cetyltrimethylammonium bromide (CTAB), the analytic performances of MIL-101 (Cr) towards BPA detection were greatly improved. Compared with pure MIL-101 (Cr), the differential pulse voltammetry (DPV) behavior of CTAB/MIL-101 (Cr) was improved 3.0 times in the presence of BPA. The hydrophobic long chain alkanes of CTAB can improve the enrichment and electrochemical oxidation for BPA. The CTAB/MIL-101 (Cr) sensor exhibited a linear range from 20 to 350 nM and a low detection limit of 9.95 nM (LOD = 3sb/S) and showed good reproducibility, stability and selectivity. Finally, real samples of dusts from E-waste recycling area in South China were collected and the CTAB/MIL-101 (Cr) sensor demonstrated satisfactory results for BPA detection from these dust samples.

A new photo-electrochemical sensor based on MIL-101(Cr) MOF/carbon black (CB) is fabricated and characterized. By using differential pulse voltammetry, dopamine (DA) can be effectively detected using a photo-electrochemical MIL-101(Cr)/CB sensor under visible light. The CB acts as the electron bridge to combine with the large specific surface area and photo-catalytic feature of MOF, which contribute to the improvements of sensitivity of DA detection. The concentration of the catalyst, pH value, accumulation potential, and accumulation time were also optimized. Furthermore, the electrochemical performances of MIL-101(Cr)/CB sensor was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scan rate, electrochemically active surface area (ECSA), and amperometric responses. A detection limit of 0.38 nM (LOD = 3 sb/S, sb = 0.028) and a working range of 1 nM to 2.22 μM has been achieved. The MIL-101(Cr)/CB sensor exhibits excellent reproducibility, stability, and selectivity and also has satisfactory recovery rate for the analysis of real samples including calf serum and human urine.

To explore the mechanism of a false-negative result from karyotyping of chorionic villi cells for a trisomy 13 fetus featuring multiple malformations.For a fetus with multiple malformations by ultrasonography and a 46,XY karyotype by chorionic villi analysis, amniocytes were further analyzed with quantitative fluorescence PCR (QF-PCR), G-banded karyotyping and chromosomal microarray analysis (CMA). Meanwhile, non-invasive prenatal testing (NIPT) was conducted on peripheral blood sample from the pregnant woman to determine the chromosomal composition of cytotrophoblast. After induction of labor, common aneuploidies in placenta and fetal tissue were also analyzed by QF-PCR.QF-PCR, chromosomal karyotyping and CMA analysis of the amniocytes all suggested complete trisomy 13 (47,XY,+13) in the fetus. NIPT also suggested existence of fetal trisomy 13. QF-PCR analysis of the placenta and fetal tissues revealed that cells derived from the maternal surface and right side of fetal surface harbored mosaic trisomy 13, while those derived from other sites of fetal surface of the placenta, umbilical cord, amniotic membrane and fetal muscle tissue harbored trisomy 13.Karyotyping of long-term cultured chorionic villus sample may give rise to false negative results due to placental mosaicism. To ensure accurate prenatal diagnosis, discordance between karyotyping of chorionic villi cells, fetal ultrasound and NIPT result should be verified by amniocentesis or cordocentesis and application of multiple cytogenetic and molecular techniques.

In this paper, the detection performances of carbon black (CB) for bisphenol A (BPA) can be greatly improved by using a surfactant of cetyltrimethylammonium bromide (CTAB). The cyclic voltammetry (CV) behavior of CTAB/CB for BPA can be improved 6 times, compared with CB. The hydrophobicity of the CTAB long-chain alkyl end can enhance the enrichment ability of BPA. Meanwhile, CB can act as an electron transmission bridge to accelerate the electrons transfer to external circuit, thereby improving the sensing signal of CTAB/CB sensor for BPA. The sensor displays a linear range of 0.04 to 0.99 μM, a low detection limit of 0.013 μM and has good reproducibility and selectivity. Finally, the sensor can also be successfully used for detecting BPA in actual samples including tap water and human urine.

To detect mutations of SLC25A13 gene in 20 families affected with citrin deficiency and provide prenatal diagnosis for them.The 20 probands and their parents were subjected to high-frequency mutation screening combined with Sanger sequencing. After confirming the genotype of each pedigree, genetic counseling and prenatal diagnosis were performed for their subsequent pregnancies.Biallelic pathogenic mutations of the SLC25A13 gene were identified in all probands. These included three deletions (c.851del4, c.1092_1095delT, and c.495delA), two splice-site mutations (IVS6+5G to A and IVS11+1G to A), two nonsense mutations (c.775C to T (p.Q259X) and c.72T to A (p.Y24X)), one duplication mutation (c.1638_1660dup), one insertion (IVSl6ins3kb), and one missense mutation (c.1775A to C (p.Q592P)). Among 24 fetuses undergoing prenatal diagnosis, 8 had normal genotypes, 11 were mutation carriers, while 5 harbored biallelic mutations. Those with wild type alleles or heterozygous SLC25A13 mutations were delivered. Two fetuses harboring homozygous c.851del4 mutations were also delivered. Three fetuses harboring biallelic mutations were terminated.Analysis of SLC25A13 gene mutations in families affected by citrin deficiency can provide evidence for molecular diagnosis and facilitate genetic counseling and prenatal diagnosis for the subsequent pregnancy, which can effectively reduce the risk of birth of further affected children.

We have established an induced pluripotent stem (iPS) cell line using urine-derived cells from a 27-year-old male patient with retinitis pigmentosa associated with point mutations in the USH2A gene. Feeder-free culture conditions and the integration-free CytoTune™-iPS 2.0 Sendai Reprogramming Kit were used.

To explore the genotype-phenotype correlation of a child with chromosome 18q deletion syndrome.G-banded karyotyping, single nucleotide polymorphism array (SNP array) and fluorescence in situ hybridization (FISH) were performed on the child with abnormal phenotypes. Genotype-phenotype correlation was explored following accurate mapping of the breakpoints on chromosome 18q. SNP array was also performed on the genome DNA derived from peripheral venous blood samples from both parents.Chromosomal analysis revealed that the child has a karyotype of 46, XY, del(18) (q23). SNP array analysis detected a 9.855 Mb deletion (chr18: 68 158 880-78 014 123) at 18q22.2q23. Mapping of the breakpoints suggested that the deletion has overlapped with that of distal chromosome 18q deletion syndrome and encompassed several critical regions for this syndrome. SNP array performed on parental samples suggested that the 18q22.2q23 deletion was de novo in origin. FISH analysis of peripheral blood sample from the child confirmed the presence of 18qter deletion.The phenotype of this child may be attributed to the deletion of distal 18q22.2q23, which has encompassed several critical regions for the 18q deletion syndrome.

Major histocompatibility complex (MHC) tetramer technology is critical for characterization of antigen-specific T cells. In the present study we reported the successful generation of HLA-A*0203 tetramer loaded with Epstein-Barr virus EBNA3(596-604) peptide (SVRDRLARL, SVR). Prokaryotic expression vector for the ectodomain of the heavy chain of HLA-A*0203 fused with a BirA substrate peptide (HLA-A*0203-BSP) was constructed and the expression conditions of the fusion protein in Escherichia coli (E. coli) were optimized. The fusion protein was highly expressed in inclusion bodies within E. coli. It was then refolded in the presence of beta2-microglobulin and SVR peptide to form a soluble HLA-A*0203-SVR monomer. After biotinylation with BirA, the monomer was purified by anion-exchange chromatography and its purity was up to 95%. The tetramer was then formulated by mixing the biotinylated monomer with streptavidin-PE at a ratio of 4:1. Flow cytometry showed that this tetramer could specifically react with antigen-specific CD8+ T cells, indicating that it was biologically functional. These results provide a foundation for further characterization of antigen-specific CD8+ T cells from HLA-A*0203 subjects.

MHC/peptide tetramer technology has been widely used to study antigen-specific T cells, especially for identifying virus-specific CD8+ T cells in humans. The tetramer molecule is composed of HLA heavy chain, beta2-microglobulin (beta2m), an antigenic peptide, and fluorescent-labeled streptavidin. To further investigate the HLA-A*1101-restricted CD8+ T cell responses against human cytomegalovirus (HCMV), we established an approach to prepare HLA-A*1101 tetramer complexed with a peptide from HCMV. The cDNA encoding HLA-A*1101 heavy chain was cloned and the prokaryotic expression vector for the ectodomain of HLA-A*1101 fused with a BirA substrate peptide (HLA-A*1101-BSP) at its carboxyl terminus was constructed. The fusion protein was highly expressed as inclusion bodies under optimized conditions in Escherichia coli. Moreover, HLA-A*1101-BSP protein was refolded in the presence of beta2m and an HCMV peptide pp65(16-24) (GPISGHVLK, GPI). Soluble HLA-A*1101-GPI monomer was biotinylated and purified to a purity of 95%, which was subsequently combined with streptavidin to form tetramers at a yield of80%. The HLA-A*1101-GPI tetramers could bind to virus-specific CD8+ T cells, suggesting soluble HLA-A*1101-GPI tetramers were biologically functional. This study provides the basis for further evaluation of HLA-A*1101-restricted CD8+ T cell responses against HCMV infection.

Major histocompatibility complex (MHC) class I tetramer technology has become the central technique for analyzing antigen-specific CD8(+) T cell responses and it has been widely used to explore the differentiation and formation of memory CD8(+) T cells. Previously, a simplified and efficient procedure for preparing high quality HLA-A*0201 tetramers has been established in our lab and the tetramers loaded with HCMV peptide pp65(495-503) has been successfully applied to investigate HCMV-specific CD8(+) T cells in Chinese populations. Using similar procedure we reported here the construction of HLA-A*0201 tetramer loaded with another dominant epitope derived from immediate early (IE)-1(316-324) (VLEETSVML, VLE) of HCMV (A2-VLE) and characterization of this tetramer. After A2-VLE monomer was prepared and purified, its tetramer was then formed at a yield of 83%. The optimized amount of A2-VLE tetramer for staining 100 microl whole blood was 0.5 microg with incubation at 4 degrees C for 1 h. Furthermore, the dissociation constant of the tetramer binding to the specific CD8(+) T cells of one HLA-A2(+) donor was estimated to be 32.7 nmol/L, which is markedly higher than that of MHC monomer. The construction of A2-VLE tetramer provides an alternative choice for investigating HCMV-specific CD8(+) T cell responses and will deepen our understanding of the differentiation and formation of HCMV-specific memory CD8(+) T cells.