Magnesium alleviates growth inhibition under low potassium by enhancing photosynthesis and carbon-nitrogen metabolism in apple plants.

Potassium (K) and magnesium (Mg) play analogous roles in regulating plant photosynthesis and carbon and nitrogen (C-N) metabolism. Based on this consensus, we hypothesize that appropriate Mg supplementation may alleviate growth inhibition under low K stress. We monitored morphological, physiological, and molecular changes in G935 apple plants under different K (0.

MdBT2 regulates nitrogen-mediated cuticular wax biosynthesis via a MdMYB106-MdCER2L1 signalling pathway in apple.

Cuticular waxes play important roles in plant development and the interaction between plants and their environment. Researches on wax biosynthetic pathways have been reported in several plant species. Also, wax formation is closely related to environmental condition.

[Effects of potassium levels on translocation of C-photoassimilates to fruit in 'Fuji' apple during fruit expanding period].

A field experiment was carried out in a six-year old 'Fuji'3/M26/Malus hupehensis Rehd. apple with the C tracer method to examine the changes of chlorophyll fluorescence parameters, photosynthetic characteristics of leaf, sugar transporter gene expression, C assimilation capability and the characteristics of translocation and distribution of C-photoassimilates to fruit under different levels of potassium addition (KO 0, 0.5%, 1.

[Effects of potassium supply on the growth, photosynthesis and N and C absorption and utilization of M9T337 seedling].

Hydroponic experiment was carried out on M9T337 seedlings using N and C isotope tracer technology to study the effects of different potassium supply levels (K, K, K, K and K were equivalent to 0, 3, 6, 9 and 12 mmol·L, respectively) on the growth, photosynthetic characteristics and N and C absorption and utilization of M9T337 seedlings. The results showed that dry mass, root length, root surface area, number of tips and root activity of M9T337 seedlings under the K level were significantly higher than those under other levels. The net photosynthetic rate (P) of leaves increased at low K concentration and then decreased with the increases of potassium supply level, and reached the maximum value at K treatment (15.

[Effects of nitrogen application levels on translocation and distribution of C-photosynthate and N to fruit from leaves of apple tree].

A field experiment was carried out in a six-year old 'Fuji3'/M26/Malus hupehensis Rehd. apple with N and C labeled tracers, to understand C assimilation capability and the characteristics of translocation and distribution of C-photosynthate and N to fruit under different nitrogen application levels (urea 0%, 0.6%, 1.

Dynamics of growth and nitrogen accumulation and utilization of young apple trees.

Taking 6-year-old Yanfu3/SH6/Malus hupehensis Rehd. as the test material, the dynamics of plant growth and nitrogen (N) accumulation under seven periods from germination stage to fruit maturity stage were examined by destructive analysis. The absorption, utilization, and distribution of fertilizer N were studied by N isotope tracer technique to clarify the N accumulation dynamics of apple trees and the maximum efficiency period of fertilizer N, and to provide theoretical basis for scientific application of N fertilizer.

Green fluorescent protein as marker in chondrocytes overexpressing human insulin-like growth factor-1 for repair of articular cartilage defects in rabbits.

Objective: To label the primary articular chondrocytes overexpressing human insulin-like growth factor (hIGF 1) with green fluorescent protein (GFP) for repair of articular cartilage defects in rabbits.

Methods: GFP cDNA was inserted into pcDNA3.1 hIGF 1 to label the expression vector.

[Effects of BMP-2 gene therapy on vascularization in repairing bone defects].

Objective: To study the effects of BMP-2 gene therapy on vascularization in repairing bone defects.

Methods: The isolated rabbit mesenchymal stem cells (rBMSC), after being transfected by adenovirus carrying BMP-2 gene (Ad-BMP-2) and seeded on xenogeneic bone scaffolds, were used to repair 1.5 cm-long radius bone defects.

The expression of N-cadherin, fibronectin during chondrogenic differentiation of MSC induced by TGF-beta(1).

Objective: To investigate the role of N-cadherin and fibronectin during chondrogenesis.

Methods: Immunohistochemical method and autibody induced changes of aggregation of cells were used to assay the expressions of N-cadherin and fibronectin during cell differentiation.

Results: The N-cadherin was present in the area of the cell nodular area in the 24 hours group after adding chondrogenic revulsant, then there was a down-regulating trend.

[Research on chondrogenic differentiation and immunologic response of allogeneic mesenchymal stem cells implanted into joint cavity].

Objective: To evaluate the cartilage formation ability of allogeneic mesenchymal stem cells implanted into sheep joint cavity without the use of immunosuppressive therapy.

Methods: Allogeneic mesenchymal stem cells (MSCs) loaded onto porous beta-tricalcium phosphate ceramic (beta-TCP) were implanted into normal sheep joint cavity. A complete mismatch between donor stem cells and recipient sheep was confirmed by mixed lymphocyte reaction assays prior to implantation.

Labeling of human insulin-like growth factor-I eukaryotic expression vector with green fluorescent protein.

Objective: To label human insulin-like growth factor-I (hIGF-I) eukaryotic expression vector with green fluorescent protein (GFP) for the repair of articular cartilage defects.

Methods: GFP cDNA was inserted into pcDNA(3.1)-hIGF-1 to construct the co-expression vector with two multiple cloning sites mammalian expression vector under two cytomegalovirus promoters/enhancers respectively.

[Experimental study on the prevention of epidural scar adhesion with polycaprolactone/polylactic acid membrane].

Objective: To evaluate the ability of a polycaprolactone/polylactic acid (PCL/PLA) membrane to inhibit epidural scar adhesion after laminectomy, and observe the responsive changes of the pain media in the spinal cord.

Methods: L(1), L(3) laminectomies were performed on 96 Wistar rats. The rats were divided into 3 groups: None-implant Control Group (NC), Autologous free fat graft group (AFFG) and PCL/PLA membrane group (PCL/PLAm).

Comparative study on seeding methods of human bone marrow stromal cells in bone tissue engineering.

Background: In general the traditional static seeding method has its limitation while the dynamic seeding method reveals its advantages over traditional static method. We compared static and dynamic seeding method for human bone marrow stromal cells (hBMSCs) in bone tissue engineering.

Methods: DNA assay was used for detecting the maximal initial seeding concentration for static seeding.

[Orthopaedic applications for biodegradable and absorbable internal fixation of fractures].

Objective: To illustrate the effect and complication of orthopedic applications for biodegradable and absorbable internal fixation of fractures, and to indicate the existent problem and research aspect currently.

Methods: The recent literatures on orthopedic applications and study of biodegradable and absorbable internal fixation for fractures were reviewed. The effect of biodegradable materials on bone healing was summarized.