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排序方式: 共有2914条查询结果,搜索用时 78 毫秒
1.
目的探讨双吲哚马来酰亚胺衍生物L6诱导白血病细胞的凋亡作用及其分子机制。方法采用MTT比色法检测L6对白血病细胞HEL、K562、KG1a的杀伤作用。流式细胞术检测L6对HEL细胞凋亡、周期和分化的影响。Western blotting法检测细胞凋亡相关蛋白的表达。通过体内实验研究L6治疗小鼠白血病的作用效果。结果 MTT比色法结果显示L6对HEL、K562、KG1a细胞具有比阳性对照米哚妥林(PKC412)更显著的抑制活性,半数抑制浓度(IC50)分别为(0.05±0.03)、(0.32±0.01)、(0.19±0.10)μmol/L。L6可以诱导HEL细胞发生凋亡和G2/M期阻滞,诱导HEL细胞向巨核细胞方向分化,且呈剂量效应。Western blotting检测结果表明L6主要通过激活Caspase-3执行细胞凋亡。小鼠肝组织苏木精-伊红(HE)染色显示肝组织内HEL细胞浸润有所减轻,但L6组减轻的效果更明显,表明其可延缓白血病细胞的转移,且效果优于米哚妥林。结论双吲哚马来酰亚胺衍生物L6有较强的抗白血病活性,为新型白血病药物的研发提供参考。  相似文献   
2.
Objective: In this study, we aimed to harness some solvent extracts of one wild mushroom Hexagonia glabra and test their anti-cancer activity against cervical human cell lines, namelyHeLa, SiHa, and CaSki. Methods: It includes cell morphological study by microscope, nuclear morphology by DAPI staining under fluorescence microscopy, apoptosis assay by fluorescence technique, anti-proliferation by MTT assay and expression of apoptotic and anti-apoptotic genes by Western blotting and cell cycle analysis was done. Results: The selected cervical cancer cells were treated separately with 150 µg/mL of three extracts, namely of ethanolic (EE), ethyl acetate (EAE), and water extract (WE) and exhibited features like round, shrink and dead. All extracts caused apoptosis in cell lines and EE had the highest effect in this regard. The percentages of apoptotic cells in HeLa, SiHa and CaSki, at the same concentration of EE were 79.23, 75.42, and 76.36% respectively. Cytotoxicity assay showed that all three extracts (50 – 250 μg/mL) were potent for inhibition of cell growth of three cell lines and again EE had the highest effect. The percentages of cell growth inhibition in HeLa, SiHa, and CaSki cells treated with EE at 24 h at 50 µg/mL were 45.79±4.11, 41.66±4.03, and 36.72±2.67, while they were 74.23±7.45, 62.31±5.97, and 54.23±5.04 at 150 µg/mL concentration. At 250 µg/mL concentration, the percentages of cell growth inhibition were 94.25 ±8.11, 90.02 ±8.67, and 85.43±6.21, respectively. The expression of apoptotic gene (Caspase 3, 9) and tumor guard gene (p53), as their proteins in Western blotting increased . However, anti-apoptotic BcL2 gene of all cell lines was decreased following treatment with extracts. In addition, the cell cycle analysis (CaSki cell) showed that treatment (EE) arrested at G2/M check point cell cycle. Conclusion: All extracts of this mushroom were active in arresting growth of three cell lines and EE had the highest effect, indicating that this mushroom can be a valuable source of anticancer agents.  相似文献   
3.
目的优选超临界CO_2提取厚朴有效成分的工艺并探讨厚朴超临界CO_2提取物的抗氧化活性。方法采用HPLC法测定厚朴超临界CO_2提取物中厚朴酚与和厚朴酚的含量,正交试验优选厚朴超临界CO_2提取工艺,MTT法检测提取物抗氧化活性。结果厚朴酚优化工艺为萃取压力25 MPa,萃取温度55℃,CO_2用量30 kg;和厚朴酚最佳提取工艺压力15 MPa、萃取温度50℃、CO_2用量25 kg。厚朴超临界CO_2提取物具有抗氧化活性,且分离参数不同,抗氧化活性有显著差异。结论在所优选的提取工艺条件下,厚朴酚、和厚朴酚的提取效率较高,重复性较好,工艺稳定可行,提取物具有良好的抗氧化活性。  相似文献   
4.
Pancreatic cancer (PC) is one of the common malignant tumors in digestive tract with a high fatality rate. The oncogenic role of lysine-specific demethylase1 (LSD1/KDM1?A) has been well recognized in PC. While, the role of its homolog LSD2 (KDM1B) in regulating PC progression is poorly understood. In this study, we attempted to evaluate the functional role of KDM1B in PC cells. The expression of KDM1B was detected by immunohistochemistry and immunoblotting in PC tissues and cells. Lentivirus-mediated shRNA was applied to silence KDM1B in PANC-1 and SW1990 cells. Cell proliferation was measured by MTT and Celigo assay. Cell apoptosis was determined by both Caspase-Glo®3/7 assay and Flow cytometry. Intracellular signaling molecules were detected using a PathScan intracellular signaling array kit. In this study, we found KDM1B was highly expressed in PC tissues compared to paracancerous tissues. Moreover, elevated expression of KDM1B was detected in PC cell lines (BxPC-3, CFPAC-1, PANC-1 and SW1990) as compared with a normal human pancreatic duct epithelial cell line (HPDE6-C7). Further investigations revealed that KDM1B knockdown significantly inhibited PC cell proliferation. Furthermore, the apoptosis of PANC-1 and SW1990 cells was significantly increased after KDM1B knockdown. Notably, the activations of p-ERK1/2, p-Smad2, p-p53, cleaved PARP, cleaved Caspase-3, cleaved Caspase-7, p-eIF2a and Survivin were promoted by KDM1B knockdown, while IkBa was suppressed. Taken together, our findings provided new insights into the critical and multifaceted roles of KDM1B in the regulation of cell proliferation and apoptosis, and offered a potentially novel target in preventing the progression of PC.  相似文献   
5.
Objective: Tea (Camellia sinensis Linn.; family: Theaceae) is popular as a stimulant beverage across the globe and is also utilized as a functional antioxidant in alternative medicine. This study has evaluated the impact of seasonal variation on phyto-constituents of tea.

Method: The antiproliferative potential of methanolic extracts of tea leaves collected in the rainy season (MECR) was compared with the extract of tea leaves collected in the autumn season (MECA) of the same mother plant. Evaluation of in vivo antitumor activity was carried out in adult female Swiss albino mice groups inoculated with Ehrlich ascites carcinoma (EAC) cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to compare efficacy of MECR with that of MECA in the EAC cell line. Both qualitative and quantitative tests for phytochemical constituents present in MECA and MECR were performed. Antitumor efficacy of both the extracts was determined by evaluating different tumor markers showing dose-dependent cytotoxicity.

Results: Statistically significant reduction in EAC-induced tumor was observed in MECR treated mice compared to MECA treated ones. Cell decimation was significantly higher with MECR treatment, where restoration of different parameters including tissue structures returned to normal. Moreover, gas chromatography–mass spectrometry (GC-MS) study revealed the presence of cyclobarbital and benzazulene derivative in MECR, which is thought to be a novel source of these chemicals.

Conclusions: To our knowledge, there is no report that has attempted to reveal nutritional changes in terms of efficacy and variation in anticancer constituents in tea leaves, plucked in two seasons. This study revealed a novel source of barbital and benzazulene derivative. The unique presence of cyclobarbital and benzazulene, as revealed from GC-MS data, in methanolic extract of tea leaves collected during the rainy season (MECR) may have contributed to its enhanced in vitro (adopting MTT assay) and in vivo (on EAC-infected Swiss albino mice) cytotoxicity vis-à-vis antiproliferative properties compared to methanolic extract of tea leaves collected during the autumn season (MECA). The nature of plucking leaves in the two selected seasons is different.  相似文献   

6.
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   
7.
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.  相似文献   
8.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
9.
Purpose: Preservatives are used in multi-dose ophthalmic topical medications in order to prevent contamination by bacteria and fungi. However, prolonged use of preserved eye drops, as it may happen in dry eye or glaucoma, may damage cells of the ocular surface. Therefore, an important goal is to find preservatives with low toxicity which are mild to host cells, still able to prevent drug contamination so to maintain their sterility and efficacy. Hence, aim of this study has been to compare the relative toxicity on a rabbit corneal cell line of a new preservative, made by the association of N-hydroxy-methyl-glycinate (NIG) with disodium-ethylene diamine tetra-acetate (EDTA), with other known and widely used eye-drops preservatives.

Materials and methods: Rabbit corneal cells (SIRC) were tested either in 96-well plates or in suspension culture. Treatments with preservatives (used at known bacteriostatic concentrations) included: benzalkonium chloride (BAK), polyquaternium-1 (PQ-1), sodium perborate (SP: NaBO3 * H2O), and NIG?±?EDTA at different concentrations (0.001% and 0.002%), and different treatment times (from 30?minutes to 120?hours). At the end of treatment, cell survival was evaluated by a specific spectrophotometric method through the metabolic conversion of MTT [3-(4,5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide] into formazan crystals.

Results: Almost no cell toxicity was evident for NIG and SP at either concentration (0.001% or 0.002%), while a low toxicity was observed for PQ-1 (62% at the highest dose at 120?hours). BAK, as expected, showed the highest toxicity (60–80% at 30?minutes, and over 90% from eight hours onward). EDTA 0.1% alone or in combination with NIG 0.002%, showed no toxicity at 24?hours, and even resulted in cell growth promotion (46% and 38%, respectively), after 48?hours of treatment.

Conclusions: These data show that the new preservative NIG/EDTA, at doses known to have effective antimicrobial properties, has a very low toxicity on corneal cells, and so it can be safely used in multi-dose eye drops.  相似文献   
10.
《Saudi Dental Journal》2022,34(5):346-354
BackgroundLipopolysaccharides (LPS) stimulate production of inflammatory cytokines. Chrysin is flavonoid beneficial for treatment of inflammatory conditions. Bone marrow mesenchymal stem cell (BM-MSC) exosomes have regenerative ability in different tissues.ObjectiveTo assess potential role of chrysin and BM-MSC exosomes on ultra-structure, viability and function of human dermal fibroblasts-adult (HDFa) stimulated by LPS.MethodsHDFa cells were divided into: Group I: Cells received no treatment. Group II: Cells were stimulated with LPS. Group III: LPS stimulated cells were treated with chrysin. Group IV: LPS stimulated cells were treated with exosomes.ResultsAfter 48 h, ultrastructural examination of HDFa cells in Group I revealed intact plasma membrane and numerous cytoplasmic organelles. Group II displayed destructed plasma membrane and apoptotic bodies. Group III showed intact plasma membrane with loss of its integrity at some areas. Group IV demonstrated intact plasma membrane that showed fusion with exosomes at some areas. Statistical analysis of MTT represented highest mean value of cell viability% in Group IV followed by Groups III, I and II respectively. Statistical analysis of enzyme-linked immunosorbent assay (ELISA) showed the highest mean value of interleukin-1β (IL-1β) was in Group II followed by Groups III, IV and I, while highest mean values of interleukin-10 (IL-10), nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins were in Group I, followed by Groups IV, III and II respectively.ConclusionsLPS have harmful consequences on ultra-structure, viability and function of HDFa cells. BM-MSC exosomes have better regenerative action on inflamed fibroblasts in comparison to chrysin.  相似文献   
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