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Cellular growth under hydrostatic pressure using bovine aortic EC-SMC co-cultured ePTFE vascular graft
SUN Lei, NIWA Koichi, LIN Jian-zhong, KARINO Takeshi
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6(2): 1-.
https://doi.org/10.1631/jzus.2005.B0079
High blood pressure (hypertension) is implicated in the development of atherosclerosis. Blood vessels are constantly subjected to stretch due to blood pressure and changes in stretch usually instigate adaptive vascular remodeling, including abnormal growth and proliferation of vascular smooth muscle cells (VSMCs) as well as extracellular matrix (ECM). In this experiment, we used bovine aortic endothelial cells and smooth muscle cells (EC-SMC) co-cultured ePTFE vascular grafts subjected to normal atmospheric pressure (as a control), and 100 mmHg hydrostatic pressure for 7 d. The increase of cell layer thickness was observed. When measured, the cell layer thickness increased by 116.2%. The increase of collagen (Type IV) synthesis was also observed in the immunohistochemistry assay. When stained with toluidine blue, the cells showed metachromatic phenomenon.
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The effect of different initial densities of nematode (Meloidogyne javanica) on the build-up of Pasteuria penetrans population
DARBAN Daim Ali, PATHAN Mumtaz Ali, BHATTI Abdul Ghaffar, MAITELO Sultan Ahmed
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6(2): 113-118.
https://doi.org/10.1631/jzus.2005.B0113
Pasteuria penetrans will build-up faster where there is a high initial nematode density and can suppress root-knot nematode populations in the roots of tomato plants. The effect of different initial densities of nematode (Meloidogyne javanica) (150, 750, 1500, 3000) and P. penetrans infected females (F1, F3) densities (F0=control and AC=absolute control without nematode or P. penetrans inoculum) on the build-up of Pasteuria population was investigated over four crop cycles. Two major points of interest were highlighted. First, that within a confined soil volume, densities of P. penetrans can increase >100 times within 2 or 3 crop cycles. Second, from a relatively small amount of spore inoculum, infection of the host is very high. There were more infected females in the higher P. penetrans doses. The root growth data confirms the greater number of females in the controls particularly at the higher inoculum densities in the third and fourth crops. P. penetrans generally caused the fresh root weights to be higher than those in the control. P. penetrans has shown greater reduction of egg masses per plant at most densities. The effects of different initial densities of M. javanica and P. penetrans on the development of the pest and parasite populations were monitored. And no attempt was made to return the P. penetrans spores to the pots after each crop so the build-up in actual numbers of infected females and spores under natural conditions may be underestimated.
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Light quality and temperature effects on antirrhinum growth and development
KHATTAK Abdul Mateen, PEARSON Simon
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6(2): 119-124.
https://doi.org/10.1631/jzus.2005.B0119
An experiment was carried out to examine the effects of light quality on the growth and development of antirrhinum under three different temperatures 19 °C, 24 °C and 27 °C in glasshouses. Five different colour filters (i.e. ‘Red absorbing’, ‘Blue absorbing’, ‘Blue and Red absorbing’ and two ‘partially Blue absorbing’ materials) were tested, with one clear polythene as a control. Plant height, internode length and leaf area were significantly affected by the spectral filters as well as the temperature. Analysis of color filter’s effect on presumed photoreceptors to exist indicated that antirrhinum plant height was regulated by the action of a blue acting photoreceptor (BAP) and not the phytochrome. There was no evidence for an effect of phytochrome or BAP on time to flowering, however, increasing temperature levels effectively decreased the time to flowering. To predict the effects of different spectral qualities and temperature, simple models were created from data on plant height, internode length and time to flowering. These models were then applied to simulate the potential benefits of spectral filters and temperature in manipulation of growth control and flowering in antirrhinum.
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Transfection and expression of exogenous gene in laying hens oviduct in vitro and in vivo
GAO Bo, SUN Huai-chang, SONG Cheng-yi, WANG Zhi-yue, CHEN Qin, SONG Hong-qin
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6(2): 137-141.
https://doi.org/10.1631/jzus.2005.B0137
To examine whether or not the regulatory sequence of chicken ovalbumin gene can drive transgene expression specifically in hen oviduct, the authors constructed an oviduct-specific expression vector (pOV), containing 3.0 kilobases (kb) of the 5′-flanking sequence and 3.0 kb of the 3′-flanking sequence of the chicken ovalbumin gene. Jellyfish green fluorescence protein (EGFP) reporter gene and bacterial LacZ reporter gene were respectively inserted into the downstream of the 5′-regulatory region. The recombinants were named as pOVEGFP and pOVLacZ. Two transfer systems, in vitro and in vivo, were used to verify the function of the vector. In vitro, the plasmid DNA pOVEGFP and pEGFP-N1 were transfected respectively by the polyethyleneimine procedure into the primary chicken oviduct epithelium (PCOE) and fibroblasts cells isolated from laying hens. In vivo, the recombinant vector pOVLacZ was injected into egg-laying hens via wing vein and the tissues were collected for RT-PCR analysis. The results showed that expression of pEGFP-N1 was achieved at low level in oviduct epithelial cells and at high level in fibroblasts, but that the recombinant vector was not expressed in both cells. RT-PCR analysis showed that the LacZ gene was transcribed in the oviduct, but not in the heart, liver, kidney and spleen of the injected hens. Accordingly, the b-galactosidase activity was only detected in the oviduct magnum (116.7 mU/ml) and eggs (16.47 mU/ml). These results indicated that the cloned regulation regions of chicken ovalbumin gene could drive exogenous gene expression specifically in the oviducts of hens. In vivo gene injection via wing vein may serve as a rapid production system of recombinant proteins in chicken eggs. In addition, the cultured primary oviduct cells from laying hens were not efficient temporary expression systems for analyzing the function of regulating elements of ovalbumin gene.
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13 articles
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