New approaches to the study of cell vital activity cultivated in different growing conditions with analysis of oxygen in the medium

Objectives to develop new approaches to the study of morphofunctional state of chondroblasts, cultured at 37C on a 3D carrier in different environments: in a CO2incubator with 5% of CO2and in a thermostat in an air-proof tube. Material and methods.The study cell culture chondroblasts, isolated from the cartilage of the articular surfaces of the extra-fingers' phalanges. 3D carrier for cells the demineralized lyophilized human spongiosa Lioplast. The resulting tissue-engineered structures were grown in a complete cell culture medium at 37С under different conditions: in a closed system in thermostat and in an open system in CO2incubator (5% CO2). To assess the morphofunctional state of the cells on the surface of the 3D carrier, the picrosirius red staining, a LIVE/DEADfluorescent dye kit, and scanning electron microscopy were used. The oxygen concentration in the culture medium was evaluated by the modified Winkler titration method. Results.The complex of morphological methods revealed the presence of living cells on the surface of human spongiosa within the 7-day period of cultivation. The cells either are fusiform or have a polygonal form and have a capacity to grow in 2 or more layers. The titrimetric analysis has demonstrated a decline in the concentration of dissolved oxygen in the medium with cellular tissue material in 7 days of cultivation. The concentration declined by 72.4% in a thermostat and by 63.5% in a CO2incubator. In the tests tubes which contained only the medium and no cells, there was a similar decline in oxygen concentration by 47.3% in a thermostat and by 66.1% in a CO2incubator. Conclusion.1. A method of measuring the amount of dissolved oxygen in a culture medium, during the adhesive cell cultivation on a 3D carrier, was developed, based on the Winkler titration method. 2. A comparative analysis of the amount of dissolved oxygen in the medium in the process of chondroblast cultivation on a 3D human spongiosa carrier, both in a CO2incubator and in a closed test tube, revealed an overall tendency to a decrease in the concentration of oxygen within 7 days of cultivation. 3. A decrease in oxygen concentration in the test tubes with human spongiosa samples (without cells), within the 7 days of cultivation, was registered. 4. An efficient and cost-saving method of graft manufacturing for the purposes of chondroplasty is the transfer of juvenile joint cartilage chondroblasts to 3D human spongiosa carriers and their further cultivation in air-proof test tubes copletely filled with medium within a period of 7 days

Efficacy of embedded metribuzin and tribenuron-methyl herbicides in field-grown vegetable crops infested by weeds

The purpose of the present study was to investigate the efficacy of the experimental formulations of the metribuzin (MET) and tribenuron-methyl (TBM) herbicides embedded in the matrix of degradable poly-3-hydroxybutyrate blended with wood flour in field-grown tomato and beet crops infested by weeds. There is a necessity to develop environmentally friendly and effective means to protect plants because of the shortcomings of the free herbicide forms such as the environmentally unsafe spray application of solutions and suspensions of the widespread metribuzin and tribenuron-methyl herbicides, removal from soil during watering events and rains, and transport to natural aquatic environments, where the herbicides accumulate in the trophic chains of biota. Free TBM is also rapidly inactivated in soil and metabolized to nontoxic products in plants. The efficacy of experimental formulations of metribuzin and tribenuron-methyl embedded in the matrix of degradable poly-3-hydroxybutyrate blended with wood flour was tested in field-grown tomato and beet crops infested with weeds. Application of metribuzin resulted in the highest productivity of tomatoes (2.3 kg/m2) and table beet (3.4 kg/m2), improved biometric parameters of tomato fruits and beet roots, and caused reduction in nitrate nitrogen concentrations in them. The mode of herbicide delivery did not affect sugar contents, but application of both metribuzin and tribenuron-methyl induced a 1.7-fold and 1.4-fold, respectively, increase in vitamin C concentrations in tomato fruits and beet roots relative to the vegetables grown on the subplots treated with free herbicides and the intact plants. Embedded herbicides can be used as preemergence herbicides in the field

Efficacy of embedded metribuzin and tribenuron-methyl herbicides in field-grown vegetable crops infested by weeds

The purpose of the present study was to investigate the efficacy of the experimental formulations of the metribuzin (MET) and tribenuron-methyl (TBM) herbicides embedded in the matrix of degradable poly-3-hydroxybutyrate blended with wood flour in field-grown tomato and beet crops infested by weeds. There is a necessity to develop environmentally friendly and effective means to protect plants because of the shortcomings of the free herbicide forms such as the environmentally unsafe spray application of solutions and suspensions of the widespread metribuzin and tribenuron-methyl herbicides, removal from soil during watering events and rains, and transport to natural aquatic environments, where the herbicides accumulate in the trophic chains of biota. Free TBM is also rapidly inactivated in soil and metabolized to nontoxic products in plants. The efficacy of experimental formulations of metribuzin and tribenuron-methyl embedded in the matrix of degradable poly-3-hydroxybutyrate blended with wood flour was tested in field-grown tomato and beet crops infested with weeds. Application of metribuzin resulted in the highest productivity of tomatoes (2.3 kg/m2) and table beet (3.4 kg/m2), improved biometric parameters of tomato fruits and beet roots, and caused reduction in nitrate nitrogen concentrations in them. The mode of herbicide delivery did not affect sugar contents, but application of both metribuzin and tribenuron-methyl induced a 1.7-fold and 1.4-fold, respectively, increase in vitamin C concentrations in tomato fruits and beet roots relative to the vegetables grown on the subplots treated with free herbicides and the intact plants. Embedded herbicides can be used as preemergence herbicides in the field