OsAPX4 gene response to several environmental stresses in rice (Oryza sativa L.)

Expression of the gene, OsAPX4, coding for ascorbate peroxidase in leaves and roots of rice were induced by abiotic stresses, such as NaCl, NaHCO3 and Na2CO3, polyethylene glycol (PEG) 6000, H2O2, CuCl2. Yeast (Saccharomyces cerevisiae) over-expressing ascorbate peroxidase exhibited greater tolerance to NaCl and NaHCO3 and transgenic Arabidopsis over-expressing OsAPX4 had a greater salt tolerance than wild-type plants in 1/2 Murashige and Skoog (MS) medium with 150, 200 mM NaCl and 5, 7.5 mM NaHCO3. These results suggest that OsAPX4 plays an important role in multiple environmental stresses.Keywords: Arabidopsis, Oryza sativa, thaliana, carbonic anhydrase ascorbate peroxides, gene expression stressAfrican Journal of Biotechnology Vol. 9(36), pp. 5908-5913, 6 September, 201

Study on Matching Ability Between Cement Particle Size and Permeability in the Process of Oil Reservoir Plugging

In order to satisfy the plugging demands of injecting the cement plugging agent into reservoirs with different radial depths, the technical studies of cement particle size optimization should be conducted. Through indoor experiment, the relationship between cement particle size and permeability was investigated by both macroscopic and microcosmic analysis. It is observed that the reservoirs which permeabilities are within 50~200mD are matching well with the cement agents which particle sizes are less than 5μm. And the permeabilities within 200~400mD are matching well with the cement agents which particle sizes are within 5~10μm, the permeabilities within 400~700mD are matching well with the cement agents which particle sizes are within 10~20μm, the permeabilities are above 700mD are matching well with the cement agents which particle sizes are more than 20μm. The plugging success rates of all the matching experiments are exceeding 90%. This research result is important to direct the plugging operation in the field.Key words: Plugging off and channeling prevention; Cement particle size; Permeability; Matching relationship; Experimental stud

A near-perfect invisibility cloak constructed with homogeneous materials

A near-perfect, non-singular cylindrical invisibility cloak with diamond cross section is achieved by a two-step coordinate transformation. A small line segment is stretched and then blown up into a diamond space, and finally the cloak consisting of four kinds and eight blocks of homogeneous transformation media is obtained. Numerical simulations confirm the well performance of the cloak. The operation bandwidth of the cloak is also investigated. Our scheme is promising to create a simple and well-performed cloak in practice.Comment: 7 pages, 4 figures, published in Optics Expres

Genetic transformation and analysis of rice OsAPx2 gene in Medicago sativa.

The OsAPx2 gene from rice was cloned to produce PBI121::OsAPx2 dual-expression plants, of which expression level would be increasing under stressful conditions. The enzyme ascorbate peroxidase (APX) in the leaves and roots of the plants increased with increasing exposure time to different sodium chloride (NaCl) and hydrogen peroxide (H(2)O(2))concentrations, as indicated by protein gel blot analysis. The increased enzyme yield improved the ability of the plants to resist the stress treatments. The OsAPx2 gene was localized in the cytoplasm of epidermal onion cells as indicated by the instantaneous expression of green fluorescence. An 80% regeneration rate was observed in Medicago sativa L. plants transformed with the OsAPx2 gene using Agrobacterium tumefaciens, as indicated by specific primer PCR. The OsAPx2 gene was expressed at the mRNA level and the individual M. sativa (T#1,T#2,T#5) were obtained through assaying the generation of positive T2 using RNA gel blot analysis. When the seeds of the wild type (WT) and the T2 (T#1,T#5) were incubated in culture containing MS with NaCl for 7 days, the results as shown of following: the root length of transgenic plant was longer than WT plants, the H(2)O(2) content in roots of WT was more than of transgenic plants, the APX activity under stresses increased by 2.89 times compared with the WT, the malondialdehyde (MDA) content of the WT was higher than the transgenic plants, the leaves of the WT turned yellow, but those of the transgenic plants remained green and remained healthy. The chlorophyll content in the WT leaves was less than in the transgenic plants, after soaking in solutions of H(2)O(2), sodium sulfite (Na(2)SO(3)), and sodium bicarbonate (NaHCO(3)). Therefore, the OsAPx2 gene overexpression in transgenic M. sativa improves the removal of H(2)O(2) and the salt-resistance compared with WT plants. A novel strain of M. sativa carrying a salt-resistance gene was obtained

The role of high mobility group box 1 (HMGB1) in the pathogenesis of kidney diseases

High mobility group box 1 (HMGB1) is a nuclear protein that can bind to DNA and act as a co-factor for gene transcription. When released into extracellular fluid, it plays a proinflammatory role by acting as a damage-associated molecular pattern molecule (DAMP) (also known as an alarmin) to initiate innate immune responses by activating multiple cell surface receptors such as the receptor for advanced glycation end-products (RAGE) and toll-like receptors (TLRs), TLR2, TLR4 or TLR9. This proinflammatory role is now considered to be important in the pathogenesis of a wide range of kidney diseases whether they result from hemodynamic changes, renal tubular epithelial cell apoptosis, kidney tissue fibrosis or inflammation. This review summarizes our current understanding of the role of HMGB1 in kidney diseases and how the HMGB1-mediated signaling pathway may constitute a new strategy for the treatment of kidney diseases

Antioxidative activity in the leaves of transgenic and WT alfalfa under different salinity levels.

<p>Antioxidative activity in the leaves of transgenic and WT alfalfa under different salinity levels.</p

RNA gel blot analysis on T2 transgenic alfalfa expressing <i>OsAPx2</i>.

<p>WT: untransferred alfalfa #1, 2, and 5:T2 transferred alfalfa with <i>OsAPx2.</i></p

The growth status of the WT and T2 plants under NaCl stress.

<p>WT = wild type; T2 = the first generation carried <i>OsAPx2</i>, the root of the adult plants were soaked in 200 mMNaCl solution and the plants were maintained in natural light for 7 days.</p

Subcellular localization of GFP fusion protein in the onion epidermis instant expression system.

<p>A: Localization of pBI121-<i>OsAPx2</i>::GFP protein in the cytoplasm in the micrographs; B: pBI121-GFP proteins were located throughout the cytoplasm.</p

RNA gel blot analysis of <i>OsAPx2</i> gene expression under different stresses.

<p>RNA gel blot analysis of <i>OsAPx2</i> gene expression in rice roots and leaves treated with 100 mM NaCl, 20 mM NaHCO₃, and 10% PEG 6000 for 0, 6, 12, 24, 48, and 72 h. 10 µg sample volume of total RNA.</p