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51.
Wei Dai Yong gang Dai Dong feng Ren Da wei Zhu 《Journal of biochemical and molecular toxicology》2023,37(5):e23313
This study investigated that dieckol (DKL), a natural drug, inhibits colon cancer cell proliferation and migration by inhibiting phosphoinositide-3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) phosphorylation in HCT-116 cells. The cells were treated with DKL in various concentrations (32 and 50 μM) for 24 h and then analyzed for various experiments. MTT (tetrazolium bromide) and crystal violet assay investigated DKL-mediated cytotoxicity. Dichlorodihydrofluorescein diacetate staining was used to assess the reactive oxygen species (ROS) measurement, and apoptotic changes were studied by dual acridine orange and ethidium bromide staining. Protein expression of cell survival, cell cycle, proliferation, and apoptosis protein was evaluated by western blot analysis. Results indicated that DKL produces significant cytotoxicity in HCT-116, and the half-maximal inhibitory concentration was found to be 32 μM for 24-h incubation. Moreover, effective production of ROS and enhanced apoptotic signs were observed upon DKL treatment in HCT-116. DKL induces the expression of phosphorylated PI3K, AKT, and mToR-associated enhanced expression of cyclin-D1, proliferating cell nuclear antigen, cyclin-dependent kinase (CDK)-4, CDK-6, and Bcl-2 in HCT-116. In addition, proapoptotic proteins such as Bax, caspase-9, and caspase-3 were significantly enhanced by DKL treatment in HCT-116. Hence, DKL has been considered a chemotherapeutic drug by impeding the expression of PI3K-, AKT-, and mTOR-mediated inhibition of proliferation and cell cycle-regulating proteins. 相似文献
52.
Yasuiki Umezu Lazel B Augustus Dai Seito Kazuhiro Hayakawa Merric I Ross Omar Eton David A Swanson Kyogo Itoh 《Cancer immunology, immunotherapy : CII》1993,37(6):392-399
The roles of ultraviolet-B (UV) radiation in the immunogenicity of human cancer cells have not been fully studied. We have investigated the effects of UV radiation on metastatic melanoma and renal cell carcinoma cells with regard to MHC antigen expression and the ability to induce cytotoxic T lymphocyte (CTL) activity in peripheral blood mononuclear cells (PBMC) or tumor-infiltrating lymphocytes (TIL) against untreated autologous tumor cells. UV radiation respectively decreased or increased MHC class I expression of freshly isolated tumor cells or cultured tumor cells, and also decreased MHC class I expression of starved cultured tumor cells. It increased the ability of both freshly isolated and cultured tumor cells to induce CTL activity from PBMC against untreated autologous tumor cells. UV-irradiated subclones that were more susceptible to CTL lysis were more potent for CTL induction from TIL than either an untreated parental clone or a UV-irradiated subclone that was resistant to CTL lysis. In summary, UV radiation increased the ability of tumor cells to induce CTL activity without a corresponding effect on MHC antigen expression.This work was supported in part by a grant CA47891 from the National Cancer Institute, USA, a grant-in-aid of the comprehensive 10-years strategy for cancer control from ministry of a Health and Welfare, Japan, and the Ishibashi Research Fund, Japan 相似文献
53.
Dai Xiao-bing 《植被学杂志》1993,4(1):109-114
Vegetation and biomass in six plots, each with five quadrats, in Vitex shrubland in northern China were related to type and degree of human disturbance. Canonical correspondence analysis of the vegetation and environmental data showed two lines of variation, the first one highly correlated with the degree of disturbance, but the second one appearing within the disturbed plots cannot yet be fully explained. Changes in life-form spectrum were small, but the geographical spectrum changed under heavy disturbance towards a higher proportion of tropical, subtropical and cosmopolitan species. The number of shrub species also decreased noticeably. The above-ground biomass of both Vitex and the accompanying species and the total above-ground biomass of the shrubland was negatively correlated with the intensity of disturbance. The root/stem biomass ratio in Vitex reaches values of over 5 in disturbed plots, but only between 1 and 2 in the protected plots. 相似文献
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55.
Zhizhong Dai Henry Lackland Stanley Stein Qian Li Robin Radziewicz Stephanie Williams Leonard H. Sigal 《生物化学与生物物理学报:疾病的分子基础》1993,1181(1):97-100
A monoclonal antibody (H9724), specific for the 41-kDa flagellar protein of the Lyme disease pathogen Borrelia burgdorferi, cross-reacts with human axons and detects one major protein in human neuroblastoma cell extracts. The homologous cross-reacting protein has now been isolated from calf adrenal and identified as chaperonin-HSP60 by N-terminal sequencing. 相似文献
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58.
稻根象甲种群空间格局及其受耕法的影响 总被引:5,自引:1,他引:4
本文根据36块田的调查,用种群空间格局参数I、C_A、I_δ、m~*/m和α、β值进行分析,稻根象甲幼虫和(?)≥0.6头/样方(每样方为0.5m~2)的成虫种群,在稻田均属具公共k值的负二项分布;(?)<0.6头/样方的成虫种群则为随机分布。成虫聚块的大小和面积与平均密度有关。低密度时种群的聚集主要由于环境的异质性;高密度时种群的聚集则由本身的行为习性所致。随着耕作强度的增加,幼虫种群的聚集度和越冬死亡率增大。 相似文献
59.
从四川省汶川县产平截独活Heracleum vicinum根的乙醇提取物中分离鉴定了6个成分,分别为虎耳草素(pimpinellin)(1),异佛手柑内酯(2),6-甲氧基当归素(sphondin)(3)。佛手柑内酯(bergapten)(4),异虎耳草素(isopimpincllin)(5),falcarindi01)(6). 相似文献
60.
Nguyen Huy Hung Pham Minh Quan Do Ngoc Dai Prabodh Satyal Le Thi Huong Le Duc Giang Le Thanh Hung William N. Setzer 《化学与生物多样性》2023,20(3):e202200210
There is an ongoing interest to identify alternative pesticidal agents to avoid the chronic problems associated with synthetic pesticides. Essential oils have shown promise as botanical pest control agents. In the present study, the essential oils of four members of the Lamiaceae (Callicarpa candicans, C. erioclona, C. macrophylla, and Karomia fragrans; Vietnamese names: Nàng nàng, Tu châu lông mem, Tu châu lá to and Cà diện, respectively), obtained from wild populations in Vietnam, have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils were formulated into microemulsions and the essential oils and their microemulsions were screened for mosquito larvicidal activity against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and for molluscicidal activity against Pomacea canaliculata. Atractylone and (E)-caryophyllene dominated the volatiles of C. candicans (CCEO) and C. erioclona (CEEO), while the major component in C. macrophylla (CMEO) and K. fragrans (KFEO) was (E)-caryophyllene. The essential oils and microemulsions of both C. candicans and C. erioclona exhibited excellent larvicidal activity against all three mosquito species (Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus) with LC50 values <10 μg/mL. Additionally, the larvicidal activity of the microemulsions were significantly improved compared with their free essential oils, especially for C. candicans and C. erioclona. All four essential oils and their microemulsions showed excellent molluscicidal activity with LC50 <10 μg/mL. In most cases, the essential oils and microemulsions showed greater pesticidal activity against target organisms than the non-target freshwater fish, Oreochromis niloticus. The in silico studies on physicochemical and ADMET properties of the major components in the studied essential oils were also investigated and most of the compounds possessed a favorable ADMET profile. Computational modeling studies of the studied compounds demonstrated a favorable binding interaction with the mosquito odorant-binding protein target and support atractylone, β-selinene, and caryophyllene oxide as potential inhibitors. Based on the observed pesticidal activities of the essential oils and their microemulsions, the Callicarpa species and K. fragrans should be considered for potential cultivation and further exploration as botanical pesticidal agents. 相似文献