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121.
Acute leukaemia (AL) is a critical neoplasm of white blood cells. Diagnosing AL requires bone marrow puncture procedure, which many patients do not consent to for it is invasive. Hence sensitive and specific early diagnostic biomarkers are essential for non‐invasive diagnosis, new therapeutics and improving the disease prognosis. To differentiate the metabolic alterations associated with acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML), we investigated serum of ALL and AML patients in comparison with two controls using gas chromatography coupled with triple quadrupole tandem mass spectrometry and multivariate statistical analysis. Twenty seven out of 1425 metabolites were found differentiative among ALL, AML, aplastic anaemia (APA) patients and healthy control using p‐value ≤ 0.001. ALL is the most dissimilar group from other three groups as in hierarchical clustering showed 72.1% dissimilarity. Model generation using PLSDA gave an overall accuracy of 91.9%. This study helps in metabolic fingerprinting of control and disease serum at high significance levels and could be used for early diagnosing of AL. Based on pathways analysis, fatty acid metabolism is deregulated in patients with AL and may represent an underlying metabolic pathway associated with disease progression. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Molecular mimicry between Campylobacter jejuni lipopolysaccharide and host gangliosides induces an immune response leading to axonal damage and Guillain-Barré syndrome (GBS). TLR polymorphisms are associated with many autoimmune diseases. The role of the TLR4 gene in GBS susceptibility largely remains unknown. We investigated TLR4 polymorphism in GBS. One hundred and twenty GBS patients and 150 healthy controls were included. TLR4 (Asp299Gly and Thr399Ile) genes were studied by PCR-RFLP. TLR4 (Asp299Gly) polymorphism was significantly associated with GBS (p, 0.045; OR, 8.75; 95% CI, 1.05–72.88); only acute motor axonal neuropathy (AMAN) was associated with Gly299Gly homozygote (p, 0.027; OR, 12.40; 95% CI, 1.33–115.77) and Thr399Ile (p, 0.019; OR, 3.42; 95% CI, 1.22–9.54) heterozygote, and TLR4–399Ile allele (p, 0.045; OR, 2.63; 95% CI, 1.02–6.75) compared to controls. In conclusion, TLR4 (Asp299Gly) polymorphism is associated with an increased susceptibility to GBS. Besides Asp299Gly, AMAN subtype is also associated with Thr399Ile polymorphism.  相似文献   
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In recent years a number of reports have documented the chemopreventive effect of green tea consumption on various types of cancers such as those of bladder, prostate, esophagus and stomach. This property is attributed to the presence in green tea of polyphenols known as catechins. These include epigallocatechin-3-gallate, epigallocatechin and epicatechin. In addition to their antioxidant properties plant derived polyphenolics are also capable of oxidative DNA damage particularly in the presence of transition metal ions. We have recently proposed a mechanism for cytotoxic action of plant-derived polyphenols against cancer cells that involves mobilization of endogenous copper and consequent prooxidant action. In partial support of the idea, in the present paper we show that water extract of green tea is considerably more efficient than black tea extract in DNA cleavage in the presence of copper ions. Green tea extract also shows a higher rate of Cu(II) reduction and consequent hydroxyl radical formation. Cu(II) reduction is presumably accompanied by the formation of 'oxidized species' of tea polyphenols, which in turn also appear to catalyze the reduction of Cu(II) leading to redox cycling of copper ions. The results are discussed in relation to the structural differences between polyphenols of green and black tea.  相似文献   
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Oral immunization of rabbits with four doses of 10(11) heat-killed Shigella flexneri 2a showed 100% protection against challenge with virulent S. flexneri 2a. After orally immunizing Guinea pigs with four doses of heat-killed S. flexneri 2a 100% protection could be shown against ocular challenge with the same virulent S. flexneri 2a strain but this conferred no protection against challenge with Shigella dysenteriae type 1. In enzyme-linked immunosorbent assay (ELISA) and immunoblot experiments both whole cell lysate-envelope (WCL-E) fraction and outer membrane proteins (OMPs) were recognized by the antisera. Though protective mechanism in shigellosis is not established with certainty, outer membrane proteins (specially 38, 34, 23 and 20kDa proteins) may be the major antigens in the induction of protective immune responses as indicated by this observation.  相似文献   
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PURPOSE: To identify novel treatments for pediatric solid tumors and/or for malignancies with low-level Her2/neu expression. EXPERIMENTAL DESIGN: Using fluorescence-activated cell sorting and immunohistochemistry, Her2/neu expression was determined on cell lines derived vfrom Ewing's family tumors (EFT) and neuroblastoma. Sensitivity to trastuzumab treatment was investigated using an in vitro proliferation assay. Cytotoxicity against EFT cell lines was done with either freshly isolated or ex vivo activated and expanded T cells (cytokine-induced killer cells, CIK cells), with or without addition of a CD3xHer2/neu bispecific antibody. The effects of either trastuzumab, CIK cells alone, or CD3xHer2/neu bispecific antibody redirected CIK cells was determined using a SCID/hu model of EFTs and serial, noninvasive bioluminescent imaging. RESULTS: EFT cell lines express 5- to 10-fold lower levels of her2/neu than either breast (BT-474) or ovarian (SK-OV-3) cell lines. Treatment of EFT cell lines with trastuzumab did not induce growth inhibition either in vitro or in vivo. In contrast, Her2/neu could be used to redirect CIK cell to mediate cytotoxicity against EFTs both in vitro and in vivo (using two different treatment schemas). CONCLUSIONS: CD3xHer2/neu bispecific antibody and CIK cells may be a suitable approach to treat malignancies with low-level Her2/neu expression not responsive to trastuzumab.  相似文献   
128.
It has been postulated that mushroom has beneficial effect of lowering blood glucose and cholesterol in diabetic subjects. The literature so far searched and found that there was no published data in this regard. This study was undertaken to assess the effect of reducing blood glucose, cholesterol and triglycerides in diabetic patients. Additionally, this study addressed whether there was any hepatic and renal toxicity of mushroom. This clinical investigation was conducted in BIRDEM hospital from July 2005 to January 2006. Eighty-nine subjects were recruited. Baseline investigations included height, weight, blood pressure (SBP, DBP), plasma glucose for fasting (FPG) and 2-h after-breakfast (2hPG), total cholesterol (T-chol), triglycerides (TG) and high-density lipoprotein (HDL-c). Twenty- four days' study constitutes 7-days mushroom, 7-days no mushroom and then 7-days mushroom. Investigations were done at the start and each after every 7-days. Thirty subjects (M / F = 17 / 13) followed to ensure full compliance with the designed protocol for 24 days. The mean (SD) age of the participants was 46.3 (10) years. Mushroom significantly reduced systolic and diastolic blood pressure (SBP, p<0.01; DBP, p<0.05). It also lowered both plasma glucose significantly (FPG & 2-hPG, p<0.001). Mushroom also lowered total cholesterol and TG significantly; whereas, there was no significant change in weight and HDL-c. When mushroom was withdrawn, there were significant increases of DBP, FPG, 2hPG, T-cholesterol and TG, whereas, no significant change was observed in weight, SBP and HDL-c. Restarting mushroom there was again significant reduction of blood glucose, TG and cholesterol. We conclude that mushroom significantly reduced blood glucose, blood pressure, TG and cholesterol of diabetic subjects without any deleterious effect on liver and kidney. The effect of mushroom may be investigated in a large sample for a longer duration to evaluate its efficacy and toxicity.  相似文献   
129.
Andrographolide, a diterpenoid lactone and a major constituent of Andrographis paniculata Nees, exhibits remarkable anticancer activity. However, the effect of andrographolide on colon cancer has not been completely elucidated yet. Thus, we investigated the chemopreventive potential of andrographolide in colon cancer HT-29 cells. The cytotoxic potential of andrographolide on HT-29 cells was determined by MTT assay, trypan blue exclusion assay, colony formation assay, and morphological analysis; and apoptotic property by DAPI and Hoechst staining, FITC-Annexin V assay, DNA fragmentation assay and caspase-3 activity assay. To elucidate andrographolide action, intracellular reactive oxygen species (ROS) level was determined by DCFDA dye; change in mitochondrial potential by Rhodamine123 and Mito Tracker Red CMXRos dye; and cell cycle modulatory property by flow cytometric analysis. Results of the study have shown that andrographolide decreased cell viability of HT-29 cells in a dose- and time-dependent manner. Furthermore, andrographolide induced apoptosis in HT-29 cells which seemed to be linked with augmented intracellular ROS level and disruption of mitochondrial membrane potential. Interestingly, andrographolide caused significant cell cycle arrest in G2/M phase at lower doses, but, in G0/G1 phase at higher doses. In summary, our results indicated that andrographolide exhibited antiproliferative and apoptotic properties against colon cancer HT-29 cells.  相似文献   
130.
Solar UV radiation, in particular its UVB component, is the primary cause of many adverse biological effects, the most damaging of which is skin cancer. Here, we assessed the photochemopreventive effect of delphinidin, a major anthocyanidin present in many pigmented fruits and vegetables, on UVB-mediated responses in human immortalized HaCaT keratinocytes and SKH-1 hairless mouse skin. We found that pretreatment of cells with delphinidin (1-20 microM for 24 hours) protected against UVB (15-30 mJ/cm2, 24 hours)-mediated (i) decrease in cell viability and (ii) induction of apoptosis. Furthermore, we found that pretreatment of HaCaT cells with delphinidin inhibited UVB-mediated (i) increase in lipid peroxidation; (ii) formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG); (iii) decrease in proliferating cell nuclear antigen expression; (iv) increase in poly(ADP-ribose) polymerase cleavage; (v) activation of caspases; (vi) increase in Bax; (vii) decrease in Bcl-2; (viii) upregulation of Bid and Bak; and (ix) downregulation of Bcl-xL. Topical application of delphinidin (1 mg/0.1 ml DMSO/mouse) to SKH-1 hairless mouse skin inhibited UVB-mediated apoptosis and markers of DNA damage such as cyclobutane pyrimidine dimers and 8-OHdG. Taken together our results suggest that treatment of HaCaT cells and mouse skin with delphinidin inhibited UVB-mediated oxidative stress and reduced DNA damage, thereby protecting the cells from UVB-induced apoptosis.  相似文献   
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