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31.
Metabolomics have been widely used in pregnancy-related diseases. However, physiological variations induced by chronic hypoxia during pregnancy are not well characterized. We aimed to investigate physiological variations induced by chronic hypoxia during pregnancy. A Sprague–Dawley (SD) pregnant rat model of chronic hypoxia was established. Plasma and urine metabolite profiles at different stages of the pregnancy were detected by 1H NMR (nuclear magnetic resonance). Multivariate statistical analysis was used to analyze changes in plasma and urine metabolic trajectories at different time-points. We identified hypoxia-induced changes in the levels of 30 metabolites in plasma and 29 metabolites in urine during different stages of pregnancy; the prominently affected metabolites included acetic acid, acetone, choline, citric acid, glutamine, isoleucine, lysine, and serine. Most significant hypoxia-induced changes in plasma and urine sample metabolites were observed on the 11th day of gestation. In summary, chronic hypoxia has a significant effect on pregnant rats, and may cause metabolic disorders involving glucose, lipids, amino acids, and tricarboxylic acid cycle. Metabolomics study of the effect of hypoxia during pregnancy may provide insights into the pathogenesis of obstetric disorders.  相似文献   
32.
Cancer is one of the most common malignant diseases in the world. Hence, there is an urgent need to search for novel drugs with antitumor activity against cancer cells. AMP-17, a natural antimicrobial peptide derived from Musca domestica, has antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria, and fungi. However, its antitumor activity and potential mechanism of action in cancer cells remain unclear. In this study, we focused on evaluating the in vitro antitumor activity and mechanism of AMP-17 on leukemic K562 cells. The results showed that AMP-17 exhibited anti-proliferative activity on K562 cells with an IC50 value of 58.91 ± 3.57 μg/mL. The membrane integrity of K562 was disrupted and membrane permeability was increased after AMP-17 action. Further observation using SEM and TEM images showed that the cell structure of AMP-17-treated cells was disrupted, with depressions and pore-like breaks on the cell surface, and vacuolated vesicles in the cytoplasm. Furthermore, further mechanistic studies indicated that AMP-17 induced excessive production of reactive oxygen species and calcium ions release in K562 cells, which led to disturbance of mitochondrial membrane potential and blocked ATP synthesis, followed by activation of Caspase-3 to induce apoptosis. In conclusion, these results suggest that the antitumor activity of AMP-17 may be achieved by disrupting cell structure and inducing apoptosis. Therefore, AMP-17 is expected to be a novel potential agent candidate for leukemia treatment.  相似文献   
33.
This study aims to observe the differentiating effect of shikonin on Wilms’ tumor 1 (WT1)-positive HL-60 cells and investigate the fate of the differentiated leukemia cells. WT1 overexpression unaffected cell viability but promoted resistance to H2O2-induced DNA injury and cell apoptosis. The binding of shikonin to the WT1 protein was confirmed by molecular docking and drug affinity reaction target stability (DARTS). Shikonin at the non-cytotoxic concentration could decrease the WT1 protein and simultaneously reduced the CD34 protein and increased the CD11b protein in a dose-dependent manner in normal HL-60 cells but not in WT1-overexpressed HL-60 cells. Shikonin unaffected HL-60 cell viability in 48 h. However, it lasted for 10 days; could attenuate cell proliferation, mitochondrial membrane potential (MMP), and self-renewal; prevent the cell cycle; promote cell apoptosis. In a mouse leukemia model, shikonin could decrease the WT1 protein to prevent leukemia development in a dose-dependent manner. In this study, we also confirmed preliminarily the protein–protein interactions between WT1 and CD34 in molecular docking and CO-IP assay. Our results suggest that: 1. shikonin can down-regulate the WT1 protein level for leukemia differentiation therapy, and 2. the interaction between WT1 and CD34 proteins may be responsible for granulocyte/monocyte immaturity in HL-60 cells.  相似文献   
34.
With technological advancements in the medicinal and pharmaceutical industries, numerous research studies have focused on the propolis produced by stingless bees (Meliponini tribe) and Apis mellifera honeybees as alternative complementary medicines for the potential treatment of various acute and chronic diseases. Propolis can be found in tropical and subtropical forests throughout the world. The composition of phytochemical constituents in propolis varies depending on the bee species, geographical location, botanical source, and environmental conditions. Typically, propolis contains lipid, beeswax, essential oils, pollen, and organic components. The latter include flavonoids, phenolic compounds, polyphenols, terpenes, terpenoids, coumarins, steroids, amino acids, and aromatic acids. The biologically active constituents of propolis, which include countless organic compounds such as artepillin C, caffeic acid, caffeic acid phenethyl ester, apigenin, chrysin, galangin, kaempferol, luteolin, genistein, naringin, pinocembrin, coumaric acid, and quercetin, have a broad spectrum of biological and therapeutic properties such as antidiabetic, anti-inflammatory, antioxidant, anticancer, rheumatoid arthritis, chronic obstruct pulmonary disorders, cardiovascular diseases, respiratory tract-related diseases, gastrointestinal disorders, as well as neuroprotective, immunomodulatory, and immuno-inflammatory agents. Therefore, this review aims to provide a summary of recent studies on the role of propolis, its constituents, its biologically active compounds, and their efficacy in the medicinal and pharmaceutical treatment of chronic diseases.  相似文献   
35.
系统研究了具有急性和慢性两个阶段的MSIS流行病模型.由两节构成,第1节建立和研究了具有急慢性阶段的MSIS流行病模型;第2节在第1节的基础上建立和研究了具有慢性病病程的MSIS流行病模型.第1节的模型是四个常微分方程构成的方程组.第2节的模型既含有常微分方程,又含有偏微分方程.运用微分方程和积分方程中的理论和方法,得到了这两个模型再生数R0的表达式.证明了当R0<1时,无病平衡态是全局渐近稳定性,给出了各模型地方病平衡态的存在性和稳定性条件.  相似文献   
36.
Cytotoxicity of organotin compounds is assessed and their effectiveness against leukemia is discussed. The functional groups attached to the tin atom in organotin compounds control the cytotoxicity of the compound towards the thymus gland. The four organotin moieties which have the greatest toxic effect upon the thymus gland are the tri-n-butyltin, di-n-butyltin, tri-n-propyltin and di-n-octyltin groups. Compounds containing these groups also exhibit the poorest test-control ratio (T/C) values when tested as anti-cancer agents against leukemic mice using NCI protocol.  相似文献   
37.
During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, we identified that the extracts of Thuja occidentalis (Cupressaceae) showed potent anti-proliferative activity in MT-1 and MT-2 cells. Therefore, we attempted to isolate the active components from this plant. We isolated and identified 32 compounds (1–32; eight lignans, 18 terpenoids, and six flavonoids) from the extracts of the leaves and cones. Their structures were determined by spectroscopic analysis. Several of the isolated compounds inhibited the growth of both cell lines. Lignans showed more potent activity than other classes of compounds. A comparison of the activities of compounds 1–8 revealed that the presence of a trans-lactone (linkage of C-6 to C-7) correlated with increased activity. Diterpenes showed moderate activity, and the presence of a ketone moiety at the C-7 position correlated with increased activity in compounds 12–21. In addition, biflavones showed moderate activity, and the presence of methoxy functions appeared to influence the activity of these compounds. Several lignans were lead compound of anti-cancer reagent (etoposide). In conclusion, not only lignans, but also diterpenes and/or biflavones, may be promising candidates for the treatment of adult T-cell leukemia/lymphoma.  相似文献   
38.
Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function.  相似文献   
39.
Omacetaxine is a natural product extract originating from Chinese medicine and finding therapeutic use as a potent myelosuppressive agent in leukemia. When planning in vitro cell biology experiments to assess omacetaxine activity against primary leukemic stem cells, it became apparent that the literature rarely describes the in vitro stability of the molecule, although accessible chromatographic methods have been published. Clearly whole organisms vs their component cells will differ in the way in which they handle xenobiotics, with the latter more dependent on physiochemical parameters such as pH and temperature in the absence of active metabolism or excretion. This could impact on the cells' experience of drug in culture. We therefore report here on examination of a modified, high‐performance liquid chromatography (HPLC) method with assessment of degradant production from a 72 h solution stability study, clearly demonstrating that omacetaxine is highly stable in representative cell culture conditions (37 °C, neutral pH) and persists for many days in marked contrast to its short‐half life in vivo. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
40.
为尽早预防疾病, 开展健康管理, 改善教职工的健康现状, 对2018—2021年期间宁波大学教职工的健康体检资料采用SPSS 23.0软件进行统计分析. 结果表明 2018—2021年检出前10种疾病略有不同, 4年间检出率均位于前10位的疾病有甲状腺结节、肺结节、血脂异常、高尿酸血症、心电图异常、乳腺异常. 其中每年血脂异常、肺结节及高尿酸血症检出率男性高于女性(P< 0.05), 甲状腺结节的检出率则是女性高于男性(P<0.05); 甲状腺结节、肺结节和高尿酸血症的检出率呈现逐年升高趋势(P<0.05); 每年检出的疾病随年龄变化的态势各不相同, 其中血脂异常、甲状腺结节、肺结节、心电图异常、前列腺异常的检出率随着年龄的增长而增加(P<0.05). 表明慢性非传染性疾病已成为影响教职工健康的首要危险因素. 因此, 应倡导科学的生活方式, 积极进行健康体检, 建立健康管理档案, 并进一步强化健康管理理念和教职工的健康意识, 尽可能改善教职工的健康状况.  相似文献   
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