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731.
732.
Shunji Takahashi Wai-Cheung Yip Toshiko Matsugami Goro Tamura 《Journal of plant research》1996,109(4):363-368
The ferredoxin-sulfite reductase (Fd-SiR; hydrogen-sulfide: ferredoxin oxidoreductase, EC 1.8.7.1) activities of shoot and
root of leek (Allium tuberosum) were increased by sulfate limitation in the early stage of growth. Western blot analysis demonstrated an increased amount
of SiRs in root under sulfate limitation, suggesting that SiRs were derepressed. The derepression was observed in shoot when
1.5 mM nitrate was supplied to the plants under sulfate limitation, and clearly in root when 15 mM nitrate was supplied under
sulfate limitation. When nitrate was absent from the nutrient solution, the SiR activity in both tissues was very low. Combined
with the results of the sulfate- or nitrate-limitation experiments, it is suggested that the degree of the derepression of
SiR in both tissue under sulfate limitation is affected by the concentration of nitrate, and further that the mechanism of
regulation of the SiR activity is different in each tissue. The decreases in the ratios of the total SiR activities (shoot/root)
in the latter stage of seedling growth indicate that root play a very important role in sulfate assimilation. 相似文献
733.
Chun-Wah Marcus Yuen Joanne Yip Liwei Liu Kevin Cheuk Chi-Wai Kan Hing-Cheong Cheung Shuk-Yan Cheng 《Carbohydrate polymers》2012,89(3):795-801
In this paper, a simple and versatile coacervation technique has been developed by using an ultrasound-assisted oil/water emulsion method for the preparation of antifungal agent-loaded microcapsules. Two types of chitosan microcapsules are successfully prepared. The mean particle size of the chitosan/miconazole nitrate microcapsules is 2.6 μm and that of the chitosan/clotrimazole microcapsules is 4.1 μm. The encapsulation efficiency of the chitosan/miconazole nitrate microcapsules (77.58–96.81%) is relatively higher than that of the chitosan/clotrimazole microcapsules (56.66–93.82%). The in vitro drug release performance of the microcapsules shows that the chitosan/miconazole nitrate microcapsules release about 49.5% of the drug while chitosan/clotrimazole microcapsules release more than 66.1% of the drug after 12 h under a pressure of 5 kg at pH 5.5, which is similar to the pH of human skin. The prepared drug-loaded microcapsules could be applied onto bandages or socks, and will continuously release antifungal drugs in a controlled manner under pressure. 相似文献
734.
Hon-Kan Yip Kun-Chen Lin Pei-Hsun Sung John Y. Chiang Tsung-Cheng Yin Re-Wen Wu Kuan-Hung Chen 《Journal of cellular and molecular medicine》2021,25(12):5640-5654
This study tested the hypothesis that combined therapy with human umbilical cord-derived mesenchymal stem cells (HUCDMSCs) and hyperbaric oxygen (HBO) was superior to either one on preserving neurological function and reducing brain haemorrhagic volume (BHV) in rat after acute intracerebral haemorrhage (ICH) induced by intracranial injection of collagenase. Adult male SD rats (n = 30) were equally divided into group 1 (sham-operated control), group 2 (ICH), group 3 (ICH +HUCDMSCs/1.2 × 106 cells/intravenous injection at 3h and days 1 and 2 after ICH), group 4 (ICH +HBO/at 3 hours and days 1 and 2 after ICH) and group 5 (ICH +HUCDMSCs-HBO), and killed by day 28 after ICH. By day 1, the neurological function was significantly impaired in groups 2-5 than in group 1 (P < .001), but it did not differ among groups 2 to 5. By days 7, 14 and 28, the integrity of neurological function was highest in group 1, lowest in group 2 and significantly progressively improved from groups 3 to 5 (all P < .001). By day 28, the BHV was lowest in group 1, highest in group 2 and significantly lower in group 5 than in groups 3/4 (all P < .0001). The protein expressions of inflammation (HMGB1/TLR-2/TLR-4/MyD88/TRAF6/p-NF-κB/IFN-γ/IL-1ß/TNF-α), oxidative stress/autophagy (NOX-1/NOX-2/oxidized protein/ratio of LC3B-II/LC3B-I) and apoptosis (cleaved-capspase3/PARP), and cellular expressions of inflammation (CD14+, F4/80+) in brain tissues exhibited an identical pattern, whereas cellular levels of angiogenesis (CD31+/vWF+/small-vessel number) and number of neurons (NeuN+) exhibited an opposite pattern of BHV among the groups (all P < .0001). These results indicate that combined HUCDMSC-HBO therapy offered better outcomes after rat ICH. 相似文献