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81.
A cancer microenvironment generates strong hydrogen bond network system by the positive feedback loops supporting cancer complexity and robustness. Such network functions through the AKT locus generating high entropic energy supporting cancer metastatic robustness. Charged lepton particle muon follows the rule of Bragg effect during a collision with hydrogen network in cancer cells. Muon beam dismantles hydrogen bond network in cancer by the muon-catalyzed fusion, leading to apoptosis of cancer cells. Muon induces cumulative energy appearance on the hydrogen bond network in a cancer cell with its fast decay to an electron and two neutrinos. Thus, muon beam, muonic atom, muon neutrino shower, and electrons simultaneously cause fast neutralization of the AKT hydrogen bond network by the conversion of hydrogen into deuterium or helium, inactivating the hydrogen bond networks and inducing failure of cancer complexity and robustness with the disappearance of a malignant phenotype. 相似文献
82.
Cheng Qian MD Danqi Chang MD Hang Li MD Yanggan Wang 《Journal of cellular biochemistry》2019,120(5):7771-7777
Heart failure (HF) remains a common complication after acute ST-segment elevation myocardial infarction (STEMI). Here, we aim to identify critical genes related to the developed HF in patients with STEMI using bioinformatics analysis. The microarray data of GSE59867, including peripheral blood samples from nine patients with post-infarct HF and eight patients without post-infarct HF, were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between HF and non-HF groups were screened by LIMMA package. Functional enrichment analyses of DEGs were conducted, followed by construction of a protein-protein interaction (PPI) network. The dynamic messenger RNA (mRNA) level of the hub genes during the follow-up was analyzed to further elucidate their role in HF development. A total of 58 upregulated and 75 downregulated DEGs were screen out. They were mainly enriched in biological processes about inflammatory response, extracellular matrix organization, response to cAMP, immune response, and positive regulation of cytosolic calcium ion concentration. Pathway analysis revealed that the DEGs were also involved in hematopoietic cell lineage, pathways in cancer, and extracellular matrix-receptor interaction. In the PPI network consisting of 58 nodes and 72 interactions, CXCL8 (degree = 15), THBS1 (degree = 8), FOS (degree = 7), and ITGA2B (degree = 6) were identified as the hub genes. In the comparison of patients with and without post-infarct HF, the mRNA level of these hub genes were all higher within 30 days but reached similar at 6 months after STEMI. In conclusion, CXCL8, THBS1, FOS, and ITGA2B may play important roles in the development of HF after acute STEMI. 相似文献
83.
Eight Danish Holstein cows were milked with a 1-mm thick specially designed soft liner on their right rear teat and a standard
liner mounted under extra high tension on their left rear teat. Four of the animals were overmilked for 5 min. Rear teats
were subjected to ultrasound examination on the first day and to infrared thermography on the second day. Teats were submersed
in ethanol 20 min post-milking on the second day. Ultrasonography measurements showed that teat canal length increased by
30–41% during milking. Twenty minutes after milking, teats milked with modified standard liners still had elongated teat canals
while teats milked with the soft liner were normalized. Overmilking tended to increase teat wall thickness. Approximately
80% of variability in teat canal length, from before teat preparation to after milking, could be explained by changes during
teat preparation. Thermography indicated a general drop in teat temperature during teat preparation. Teat temperature increased
during milking and continued to increase until the ethanol challenge induced a significant drop. Temperatures approached pre-challenge
rather than pre-milking temperatures within 10 minutes after challenge. Teat temperatures were dependent on type of liner.
Mid-teat temperatures post-challenge relative to pre-teat preparation were dependent on overmilking. Thermography and ultrasound
were considered useful methods to indirectly and non invasively evaluate teat tissue integrity. 相似文献
84.
Libnow S Methling K Hein M Michalik D Harms M Wende K Flemming A Köckerling M Reinke H Bednarski PJ Lalk M Langer P 《Bioorganic & medicinal chemistry》2008,16(10):5570-5583
The first indirubin-N'-glycosides were prepared based on reactions of isatin-N'-glycosides with indoxyls. The products show a significant anti-proliferative activity against various human cancer cell lines. Good results were observed for an indirubin-N'-mannoside which was shown to have medium to high anti-proliferative activity against all investigated cell lines. The highest activities and selectivities against the MCF-7 breast cancer cell line were observed for indirubin-N'-rhamnosides. 相似文献
85.
86.
C. Willemann R. Grünert P.J. Bednarski R. Troschütz 《Bioorganic & medicinal chemistry》2009,17(13):4406-4419
A series of 5,6-heteroaromatically annulated pyridine-2,4-diamines have been synthesized and their in vitro cytotoxic activities evaluated against six human cancer cell lines. Benzo[g] annulated pyrido[2,3-b]indolediamines 7a–b and 8 showed relatively high cytotoxic activity as well as most of the diamines with pyrrolo[2,3-b]pyridine 17, thieno[2,3-b]pyridine and furo[2,3-b]pyridine 26–28, 1,8-naphthyridine 32 and 34 and benzo[h]quinoline 37 skeletons. Surprisingly, pyrido[2,3-b]indolediamines 13 and 14 without benzo[g] annulation were inactive. None of the new compounds were as potent as ellipticine, the reference compound. 相似文献
87.
There are numerous reports of spiders that have become established outside of their native ranges, but few studies examine
their impact on native spiders. We examined the effect of the European hammock spider Linyphia triangularis (Araneae, Linyphiidae) on the native bowl-and-doily spider Frontinella communis (Araneae, Linyphiidae) in Acadia National Park, Maine, USA. First, we added L. triangularis to established plots of F. communis. Significantly more F. communis abandoned their webs when L. triangularis were added compared to control plots. Second, we tested whether F. communis were deterred from building webs in areas where L. triangularis was established. Significantly fewer F. communis built webs on plots with L. triangularis than on control plots. In both experiments, L. triangularis sometimes took over webs of F. communis or incorporated F. communis webs into their own webs, but F. communis never took over or incorporated L. triangularis webs. Competition between L. triangularis and F. communis for both webs and web sites may contribute to the decline of F. communis. 相似文献
88.
89.
Paracoccidioidomycosis was induced in immunized (IM) and non-immunized (NI) mice. The histopathology, the number of fungi in the lungs, the cellular (footpad test — FPT and macrophage inhibition factor assay — MIF) and humoral (immunodiffusion test) immune response were investigated serially postinfection. In the IM mice, at days 1 and 3, there was intense and predominant macrophagic-lymphocytic alveolitis with loose granulomatous reaction; at day 30, inflammation was mild. In the NI group, up to day 3, the lesions were focal; later there was formation of extensive epithelioid granuloma. The number of fungi in IM mice were always smaller than those of NI group. Immunization alone induced positive FPT and MIF indices with low titer of antibody. After infection, there was a significant decrease of the FPT indices in the IM group, which we interpreted as desensitization due to trapping of sensitized lymphocytes in the lungs. In conclusion, (1) The lesional pattern of pulmonary paracoccidioidomycosis in IM mice was similar to that of a hypersensitivity pneumonitis. This reaction was probably effective in reducing the extension of the infection and decrease the number of fungi. (2) In this model, pulmonary resistance against P. brasiliensis seems to be related to local and systemic delayed-type hypersensitivity reaction. 相似文献
90.
Intragastric ethanol infusion model for cellular and molecular studies of alcoholic liver disease 总被引:8,自引:0,他引:8
French SW 《Journal of biomedical science》2001,8(1):20-27
The intragastric alcohol infusion rat model (IAIRM) of alcoholic liver disease (ALD) has been utilized in various laboratories to study various aspects of ALD pathogenesis including oxidative stress, cytokine upregulation, hypoxic damage, apoptosis, ubiquitin-proteasome pathway and CYP2E1 induction. The basic value of the model is that it produces pathologic changes which resemble ALD including microvesicular and macrovesicular fat, megamitochondria, apoptosis, central lobular and pericellular fibrosis, portal fibrosis, bridging fibrosis, central necrosis, and mixed inflammatory infiltrate including PMNs and lymphocytes. The model is valuable because the diet and ethanol intake are totally under the control of the investigator. A steady state can be maintained with high or low blood alcohol levels for long periods. The cycling of the blood alcohol levels, when a constant infusion rate of alcohol is maintained, simulates binge drinking. Using this model the importance of dietary fat, especially the degree of saturation of the fatty acids on the induction of liver pathology, has been documented. The role of endotoxin, the Kupffer cell, TNFalpha, and NADPH oxidase have been demonstrated. The importance of 2E1 in oxidative stress induction has been shown using inhibitors of the isozyme. The importance of dietary iron in the pathogenesis of cirrhosis has been documented. Acetaldehyde has been shown to play a role in preventing liver pathology by preventing NFkappaB activation. Using the model, to maintain high blood alcohol levels is found to be necessary to demonstrate proteasomal peptidase inhibition. Ubiquitin synthesis is also inhibited at high blood alcohol levels in the IAIRM model. Oxidized proteins accumulate in the liver at high blood alcohol levels. Neoantigens derived from protein adducts formed with products of oxidation induce autoimmune mechanisms of liver injury. Thus, in many ways the model has revolutionized our understanding of the pathogenesis of ALD. 相似文献