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Zhang X.,University of North Carolina at Chapel Hill | Hu H.,Marine Fishery Institute of Zhejiang Province
Central European Journal of Chemistry | Year: 2014

In addition to its role as a carrier of genetic information, DNA has been recognized as a construction material for the assembly of different objects and structural arrangements with nanoscale features. As a result of DNA's self-recognition properties (based on the specific base-pairing of G-C and T-A), monolayer films of nucleic acids on solid supports have attracted an escalating attentions. Recently, numerous novel materials based on two-dimensional (2D) and three-dimensional (3D) DNA structures have been reported, which extends their utility to a large number of appliations. This review paper intends to be a new and comprehensive overview of recent strategies to site- specifically immobilized DNA on various materials, including carbonaceous substances, gold, and silica substrate, emphasizing the applications of site-specific DNA nanostructure-based devices for diagnostic, bioanalytical, food safety and environmental monitoring. Additionally, an up-to-date perspective is proposed at the end of this review. © Versita Sp. z o.o.

Zhang X.-N.,Paine College | Hu H.-M.,Marine Fishery Institute of Zhejiang Province
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2016

The alignment of the ionic liquid (IL) cation and anion at the interface is of interest because it would affect the surface structures and properties of IL at the interfaces. In this study, Kelvin probe force microscopy (KPFM), a scanning probe microscopy technique, was used to investigate the interfacial properties of the IL at room temperature. A model molecule, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), was selectively assembled on the lyophilic chemical patterns prepared on a substrate, forming ultrathin solid-like adsorbate layers and droplets. Because the surface potential is a direct indicator of the surface dipole, which is useful for examining molecular orientation, the surface potential maps captured by KPFM indicated that the [Bmim]Cl molecules demonstrated different orientations at the gas-liquid interface (in the form of a droplet) and at the gassolid interface (in the form of a solid-like adsorbate layer). Our results indicate that KPFM has potential for the characterization of IL molecular alignment at interfaces. © Editorial office of Acta Physico-Chimica Sinica.

Oulhen N.,Brown University | Xu D.,Brown University | Xu D.,Marine Fishery Institute of Zhejiang Province | Wessel G.M.,Brown University
Biochemical and Biophysical Research Communications | Year: 2014

Conservation of the cortical granule serine protease during fertilization in echinoderms was tested both functionally in sea stars, and computationally throughout the echinoderm phylum. We find that the inhibitor of serine protease (soybean trypsin inhibitor) effectively blocks proper transition of the sea star fertilization envelope into a protective sperm repellent, whereas inhibitors of the other main types of proteases had no effect. Scanning the transcriptomes of 15 different echinoderm ovaries revealed sequences of high conservation to the originally identified sea urchin cortical serine protease, CGSP1. These conserved sequences contained the catalytic triad necessary for enzymatic activity, and the tandemly repeated LDLr-like repeats. We conclude that the protease involved in the slow block to polyspermy is an essential and conserved element of fertilization in echinoderms, and may provide an important reagent for identification and testing of the cell surface proteins in eggs necessary for sperm binding. © 2014 Elsevier Inc. All rights reserved.

Hu H.-M.,Zhejiang University | Hu H.-M.,Marine Fishery Institute of Zhejiang Province | Yin X.-F.,Zhejiang University | Wang X.-Z.,Zhejiang University | And 2 more authors.
Journal of Separation Science | Year: 2013

This article describes a further development of our previously reported miniaturized analysis system of microchip electrophoresis with on-line chemiluminescence detection. The system, developed first time for nonaqueous microchip electrophoresis with peroxyoxalate chemiluminescence detection, consists of a suction pressure device for sample or reagent introduction, a constant voltage supplied for electrophoretic separation, an either hydrophilic or hydrophobic porous polymer plug for preventing chemiluminescence reagent flowing upstream and a spiral detection channel for enhancement of both detection sensitivity and reproducibility. Especially, by using organic solvent as BGE medium, the developed system avoided the interface problem between aqueous running buffer and low-water-content chemiluminescence solvent in previous reports. The influencing factors on chemiluminescence signal were optimized using rhodamine 6G as model molecule. The system performance was further investigated in the experiment of separation of hydrophilic rhodamine dyes and analysis of hydrophobic polycyclic aromatic hydrocarbon, providing the detection limit (S/N = 3) of 3.5 nmol/L for rhodamine 123, 6.8 nmol/L for rhodamine 6G, and 60 nmol/L for 1-aminopyrene, respectively. The experimental results showed the system offered a number of benefits, including compact structure, high sensitivity, good reproducibility, and a wide range of application prospect. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Xu D.,Marine Fishery Institute of Zhejiang Province | Xu D.,Zhejiang Ocean University | Lou B.,Marine Fishery Institute of Zhejiang Province | Bertollo L.A.C.,Federal University of Sao Carlos | Cioffi M.D.B.,Federal University of Sao Carlos
Molecular Cytogenetics | Year: 2013

Despite the theoretical and experimental progress, our understanding on sex chromosome differentiation is still diagrammatic. The accumulation of repetitive DNA sequences is believed to occur in early stages of such differentiation. As fish species present a wide range of sex chromosome systems they are excellent models to examine the differentiation of these chromosomes. In the present study, the chromosomal distribution of 9 mono-, di- and tri-nucleotide microsatellites were analyzed using fluorescence in situ hybrization (FISH) in rock bream fish (Oplegnathus fasciatus), which is characterized by an X1X2Y sex chromosome system. Generally, the males and females exhibited the same autosomal pattern of distribution for a specific microsatellite probe. The male specific Y chromosome displays a specific amount of distinct microsatellites repeats along both arms. However, the accumulation of these repetitive sequences was not accompanied by a huge heterochromatinization process. The present data provide new insights into the chromosomal constitution of the multiple sex chromosomes and allow further investigations on the true role of the microsatellite repeats in the differentiation process of this sex system. © 2013 Xu et al.; licensee BioMed Central Ltd.

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