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目的 通过测定大鼠局灶性脑缺血-再灌流后不同时点脑组织中髓过氧化物酶(MPO)和神经元特异性烯醇化酶(NSE)活性的变化,探讨炎症反应与脑缺血损伤的关系.方法 用线栓法制备大鼠左侧大脑中动脉缺血-再灌流模型,检测缺血3h再灌流后6h、12h、24h、48h、72h和7d脑组织中MPO和NSE活性、脑梗死体积的变化.结果 缺血组脑组织中NSE和MPO活性升高,再灌流后48h的NSE为(5.44±0.95)ng/ml,MPO为4.49±0.22;72h分别为(5.36±0.65)ng/l和5.96±0.19,升高最为明显.脑梗死体积随再灌流时间延长而增加,第7d梗死体积百分比为(39.18±0.63)%.局灶性缺血脑组织中MPO活性与组织损伤(NSE活性)间具有高度正相关性.结论 炎症反应是加重脑缺血损伤的重要因素. 相似文献
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Feng Li Wenqiang Guo Li Wu Tianjiao Zhu Qianqun Gu Dehai Li Qian Che 《Archives of pharmacal research》2018,41(1):30-34
Three new diketopiperazine derivatives (DKPs), saroclazines A–C (1–3) along with three known DKPs (4–6) were isolated from mangrove-derived fungi Sarocladium kiliense HDN11-84. Saroclazines A–B (1 and 2) possessed a free amide structure, which was first found in sulfur-containing aromatic DKPs. Their structures were elucidated by NMR, HRESIMS and X-ray. The cytotoxic activity of new compounds (1–3) was tested against HeLa cell lines, among which compound 2 showed an IC50 value of 4.2 µM. 相似文献
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Linfeng Wu Wu Chen Feng Li Brian R. Morrow Franklin Garcia-Godoy Liang Hong 《Journal of pharmaceutical sciences》2018,107(12):3134-3142
It is important to address the periodontitis-associated bacteria in the residual subgingival plaque after scaling and root planing to successfully treat periodontitis. In this study, we explored the possibility of exploiting the ion pairing/complexation of minocycline, Ca2+, and sulfate/sulfonate-bearing biopolymers to develop an intrapocket delivery system of minocycline as an adjunct to scaling and root planing. Minocycline-calcium-dextran sulfate complex microparticles were synthesized from minocycline, CaCl2, and dextran sulfate. They were characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. An in vitro release study was conducted to evaluate the release kinetics of minocycline from these microparticles. Agar disk diffusion assays and biofilm-grown bacteria assays were used to assess antibacterial capability. High loading efficiency (96.98% ± 0.12%) and high loading content (44.69% ± 0.03%) for minocycline were observed for these complex microparticles. Mino-Ca-DS microparticles achieved sustained release of minocycline for at least 9 days at pH 7.4 and 18 days at pH 6.4 in phosphate-buffered saline, respectively. They also demonstrated potent antimicrobial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans in agar disk diffusion and biofilm assays. These results suggested that the ion pairing/complexation of minocycline, Ca2+, and sulfonate/sulfate-bearing biopolymers can be exploited to develop complex microparticles as local delivery systems for periodontitis treatment. 相似文献
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Shuai Huang Run Wu Feng Gao Chunying Li Xianli Zhou 《Journal of natural medicines》2018,72(3):768-773
Two new flavonol glycosides, bootanenside I and II (1 and 2), along with ten known compounds (3–12), were isolated from whole plant of Liparis bootanensis Griff. Their structures were elucidated on the basis of extensive spectroscopic analyses, including high-resolution electrospray-ionization mass spectrometry (HR–ESIMS) and one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR). The cytotoxicity of the compounds was investigated against HCT116 human cancer cell line, revealing that none of them possessed considerable cytotoxic activity. Bioassays of the new metabolites showed that compounds 1 and 2 displayed moderate in vitro antiinflammatory activity by inhibiting expression of inducible nitric oxide synthase (iNOS) protein in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. 相似文献
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Huilong Wen Zhong Wu Huidong Hu Yixiong Wu Gang Yang Jiajun Lu Guang Yang Gang Guo Qirong Dong 《Journal of natural medicines》2018,72(1):57-63
Pachymic acid (PA) is a lanostane type triterpenoid isolated from Poria cocos, which possesses an anti-tumor effect in breast cancer, prostate cancer, lung cancer, and bladder cancer cells. In this study, we investigated the effect of PA on the growth and apoptosis of human immortalized cell line (HOS) and primary osteosarcoma cells by a Cell Counting Kit-8 (CCK-8) and Annexin V and propidium iodide (PI) staining, respectively. Western blot was used to measure the expression of cleaved Caspase 3, PTEN, and AKT, as well as the AKT phosphorylation. The Caspase 3 activity was determined using the Caspase-3 Colorimetric Assay Kit. From the results, PA significantly reduced cell proliferation in a concentration- and time-dependent manner. PA also induced cell apoptosis in a dose-dependent fashion. PA treatment led to increased Caspase 3 activation and PTEN expression, as well as reduced AKT phosphorylation. Moreover, Ac-DEVD-CHO (a Caspase 3/7 inhibitor) pre-treatment or PTEN knockdown partially blocked the effects of PA on cell proliferation and apoptosis. Caspase 3/7 inhibitor had an additive effect with PTEN knockdown. Collectively, our results suggested that induction of apoptosis by PA was mediated in part by PTEN/AKT signaling and Caspase 3/7 activity. This study provides evidence that PA might be useful in the treatment of human osteosarcoma. 相似文献
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In this study, chitosan-assembled zinc oxide nanoparticle (CZNP) was successfully prepared for evaluated for its anticancer efficacy against cervical cancer cells. The CZNP particles were nanosized and spherical in shape. The zinc oxide nanoparticle (ZNP) and CZNP showed significant cytotoxicity in cervical cancer cells in a concentration-dependent manner. Results showed that the enhanced cytotoxicity was mainly attributed to the reactive oxygen species (ROS) generation in the cancer cells. The apoptosis assay further revealed that apoptosis was the main reason behind the cell killing effect of the zinc oxide nanoparticles. The apoptosis was further confirmed by the nuclear chromatin assay. Live dead assay showed increased red fluorescent cell for CZNP treated cancer cells. Overall, metal oxide present in nanoparticulate dimensions will be advantageous in imparting the cytotoxicity to cervical cancer cell. 相似文献
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