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Xiujuan Zhang

Publications and source records attributed to Xiujuan Zhang.

6 recordsLinked to original sources
PubMed2006

Viral vectors for gene delivery in tissue engineering.

The goal of tissue engineering is the production of functional, biocompatible tissues by seeding cells within biological or synthetic scaffolds. One tissue engineering approach involves the genetic modification of cells that are seeded onto (or into) scaffolds prior to implantation. The genetic modification is achieved through gene delivery, with can utilize viral transduction or non-viral transfection systems. Although novel non-viral systems have continued to emerge as innovative vehicles for controlled gene delivery, viruses remain the most efficient means by which exogenous genes can be introduced into and expressed by mammalian cells. Retrovirus, adenovirus, adeno-associated virus and herpes virus are widely studied viral gene transfer systems and have attracted the most attention in the field of transduction. This review thoroughly discusses the genomic structures of each virus type, along with the advantages and disadvantages of their use in tissue engineering applications.

Adenoviridae↗
PubMed2006

[Root decomposition and nutrient release of Fraxinus manshurica and Larix gmelinli plantations].

A two-year buried bag experiment with different sizes of Fraxinus mandshurica and Larix gmelinii roots showed that the coarse (5 to approximately 10 mm), medium (2 to approximately 5 mm) and fine ( <2 mm) roots of F. mandshurica had an annual decomposition coefficient of 0.3649, 0.4381 and 0.2720, while those of L. gmelinii had the coefficient of 0.1967, 0.1955 and 0.2464, respectively. During root decomposition, large amounts of carbon and nutrients released. After buried into soil for 150 days, more than 90% of soluble sugar in all sizes of the two species roots was released, and about 40%, 71% and 95% of potassium was released from the coarse and medium, and fine roots of F. mandshurica, and all sizes of L. gmelinii roots, respectively. In the second year of the experiment, about 50% of nitrogen and 40% of phosphorus were released from the coarse and medium roots of the two species, and 60% of nitrogen and phosphorus were released from their fine roots. In the study of forest ecosystem's carbon and nutrient cycles, root decomposition shouldn't be ignored.

Carbon↗
PubMed2005

Morphology-controllable synthesis of pyrene nanostructures and its morphology dependence of optical properties.

Morphology-controllable synthesis of various pyrene nanostructures from nanoparticles to short nanorods and nanowires (long nanorods) was achieved by a simple self-assembly method. In this approach, aqueous sodium dodecyl sulfate (SDS) micelles were used as templates to direct the self-assembly of the pyrene molecules into nanorods. It was found that changing the concentration ratio of the pyrene to SDS molecules could be employed to control the aspect ratio (length to diameter) of the pyrene nanostructures from 1 to 50 or higher. Moreover, the dimensional variation was accompanied by changes of their optical properties. With the increase of the aspect ratio, the characteristic fluorescence of the isolated pyrene molecules was suppressed and concurrently replaced by the excimer emission of the pyrene nanostructures. A blue-shift was observed in the excimer emission peaks as the length of the nanorods increased. The growth mechanism and the change in optical properties of these pyrene nanostructures were discussed in detail.

Journal Article↗
PubMedDate not supplied

The influence of preparation conditions on the fluorescence properties of Eu(Sal)(3)Phen.

The influence of the synthesis conditions (method and sequence of adding reagents, reaction temperature, stirring rate) on the luminescence performance of the rare earth ternary complex compound europium-salicylic acid-(1,10-phenanthroline) [Eu(Sal)(3)Phen] was studied. We show that the method and sequence of adding reagents greatly affects the luminescence properties of the products. Within the range of synthesis temperatures (30-70 degrees C), the complex has a better luminescence performance at the lower temperature. However, performance decreased when the temperature decreased to 20 degrees C. Increase of stirring rate led to better performance in the range 200-700 r.p.m. Infrared (IR) spectroscopy, scanning electron microscopy (SEM) and wide-angle X-ray diffraction (WAXD) were utilized to characterize the structure and morphology of Eu(Sal)(3)Phen. The studies demonstrate that the crystallization of the product increased with increasing luminescence of the product. Therefore, it is proposed that increasing the crystallization of the product will enhance its luminescence performance.

Europium↗