Effects of U stress on physiological tolerance characteristics and mineral element distribution of sunflower seedlings.

The metabolism of plant mineral nutrients is crucial for plant growth and development and is a key parameter for characterising the growth state of plants in various environments. However, as a non-essential element for plants, radionuclide uranium readily accumulates in the roots, causing root toxicity and metabolic disorders of plant mineral nutrients. We used hydroponic sunflowers as experimental materials to explore the uranium tolerance features of sunflower seedlings and to compare the absorption of mineral nutrients by different root components and organs of the sunflower.

[The Effect of Doxycycline on the Expression of MMP-2 and MMP-9 in Multiple Myeloma].

Objective: To investigate the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in multiple myeloma (MM) patients, and analyze the effect of doxycycline (DOX) on the expression of MMP-2 and MMP-9 in MM cells.

Methods: The peripheral blood and bone marrow samples of MM patients were collected, and the patients were divided into three groups: newly diagnosed group, remission group and relapsed/refractory group, while the peripheral blood samples of 34 health people and the bone marrow samples of 17 IDA patients were selected as normal control and control group. The levels of MMP-2 and MMP-9 were detected by ELISA.

[Effect of Doxycycline on Intrinsic Apoptosis of Myeloma Cell Line H929 and Its Mechanism].

Objective: To investigate the mechanism of the in vitro toxicity of doxycycline to myeloma cell line H929 and also the possible pathway involved its toxicity.

Methods: Myeloma cell line H929 was treated with DOX, MEK inhibitor U0126 or RAS agonist ML-098, either alone or in combination. Then, the expression of p-MEK, caspase-3, caspase-9 and c-Jun in H929 were used to detected by Western blot; the cells proliferation and apoptosis were detected by CCK-8 assay and flow cytometry, respectively.

[Up-Regulation of PI3K/Akt Signaling Pathway in H929 Cell Line by Doxycycline Not Beneficial to Its Anti-Myeloma Effect].

Objective: To investigate the effect and possible mechanism of up-regulation of p-Akt by doxycycline (DOX) on myeloma cell line H929.

Methods: Multiple myeloma cell line H929 was treated with DOX at different concentrations for different times, and cell proliferation rate was measured by CCK-8 assay. The protein expression level of p-Akt, PTEN, p-PDK1, p-mTOR, p-GSK-3β, and p-BAD was analyzed by Western blot.