Effect of exogenous calcium on seed germination and seedling physiological characteristics of Lycium ruthenium / 中国中药杂志

<p><b>OBJECTIVE</b>In order to get the method for improving the salt resistance of Lycium ruthenium seeds and seedlings under NaCl stress, the seed germination and physiological characteristics of L. ruthenium seedlings was studied.</p><p><b>METHOD</b>Several physiological indexes of L. ruthenium seeds under NaCl stress, such as the germination rate (Gr), germination vigor (Gv), germination index (Gi), vigor index (Vi), and relative salt damage rate were measured. Other indexes of the seedlings like relative water contents (RWC) , chlorophyll contents, soluble protein contents, electrolyte leakage, the contents of malondialdehyde (MDA), and peroxidase (POD) were also measured.</p><p><b>RESULT</b>NaCl at lower concentration could promote the seed germination but inhibit the seed germination at higher concentration. After the treatment by CaCl2 at the different concentrations, all germination indexes were increased. With the increase of salt concentration, the relative water contents and the contents of chlorophyll were decreased, the content of MDA and electrolyte leakage were increased. The change trend of POD activity showed the first increase and then decrease with the increase of salt concentration, which was similar to that of the soluble protein. After the treatment by CaCl2, relative water contents, chlorophyll and POD activities were decreased more slowly, and also electrolyte leakage and MDA contents increased slowly.</p><p><b>CONCLUSION</b>The CaCl2 could significantly alleviate the damages to the seeds and seedlings of L. ruthenium under NaCl stress, and promote the salt resistance to the seeds and seedlings of L. ruthenium.</p>

The impact of fluoride on in vitro cultured human chondrocytes / 中国地方病学杂志

Objective To study the cell vitality and ultra-structure of in vitro cultured fetus chondrocytes exposed to different doses of fluoride.Methods Primary chondrocytes were obtained from articular cartilage of the 24-27 weeks,aborted and dead fetuses.The third generation of primary cultured chondmcytes were exposed to concentrations of 0,10-2,5 × 10-3,10-3,10-4,10-5,10-6,10-7 and 10-8 mol/L fluoride for 24,48 and 72 h.Cell vitality was detected with Cell Counting Kit-8 (CCK-8) and ultra-structure of chondrocytes was observed by transmission electron microscope.Results The cell vitalities of chondrocytes exposed to doses of fluoride (10-2,5 ×10-3,10-3,10-4,10-5,10-6,10-7 and 10-8 moL/L) for 24,48 and 72 h were(15.04 ± 0.55)％,(62.53 ± 1.03)％,(100.34 ± 5.19)％,(111.40 ± 3.69)％,(121.47 + 6.09)％,(129.95 ± 4.96)％,(121.81 ± 4.97)％,(111.00 ± 1.63)％;(10.35 ± 0.64)％,(35.23 ± 2.41)％,(110.30 ± 2.07)％,(113.66 ± 6.98)％,(120.36 ± 6.23)％,(133.40 ± 5.80)％,(126.06 ± 5.40)％,(115.62 ± 7.33)％; (6.19 ± 0.16)％,(18.44 ± 0.21)％,(120.83 ± 4.93)％,(123.77 ± 4.82)％,(129.09 ± 5.21)％,(140.44 + 4.18)％,(131.99 ± 7.00)％,(124.10 ± 3.68)％,respectively.The cell vitalities of 10-2,5 × 10-3 mol/L fluoride groups were significantly lower than that of the control group (all P ＜ 0.05).The cell vitality of 10-2 mol/L group was significantly lower than that of the 5 × 10-3 mol/L group (P ＜ 0.05).Doses of fluoride (10-2,5 × 10-3 mol/L) could inhibit the cell vitality and promote the apoptosis of chondrocytes in vitro with increasing doses and prolonged time.The cell vitalities of 10-3,10-4,10-5,10-6,10-7,10-8 mol/L of fluoride groups were significantly higher than that of the control group (except the 24 h 10-3 mol/L,P ＜ 0.05).Between 10-4 and 10-3 mol/L groups(the vitalities of 48 h and 72 h were higher,but not significantly); 10-5 and 10-4 mol/L groups (the vitality of 72 h was higher,but not significantly); 10-6 and 10-5 mol/L groups,the cell vitalities were significantly higher than that of the control group(all P ＜ 0.05).Between 10-7 and 10-6 mol/L groups,10-8 and 10-7 mol/L groups (the vitality of 72 h was lower,but not significantly),the cell vitalities were significantly lower than that of the control group(all P ＜ 0.05).Doses of fluoride(10-3-10-8 mol/L) could promote the cell vitality of chondrocytes in vitro with prolonged time.The optimal concentration for the promotion was 10-6 mol/L.The cells of the control group were characterized as regular morphology,the abnormal surface microvillis,abundant cytoplasm and mitochondrial,abundant and slightly expanded rough endoplasmic reticulums and low electron-dense materials.The cells of 10-6 mol/L fluoride group had the following changes,increased and swell mitochondrial,hypertrophy and expanded rough endoplasmic reticulums.The cells of 5 × 10-3 mol/L fluoride group had the following changes,decreased microvillis,invaginated cell membrane,pyknosis and apoptotic body.Conclusion Doses of fluoride (10-3-10-8 mol/L) can promote the proliferation of human chondrocytes cultured in vitro.Doses of fluoride (10-2,5 × 10-3 mol/L) can promote the apoptosis of human chondrocytes cultured in vitro.