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Kühn MW Radtke I Bullinger L Goorha S Cheng J Edelmann J Gohlke J Su X Paschka P Pounds S Krauter J Ganser A Quessar A Ribeiro R Gaidzik VI Shurtleff S Krönke J Holzmann K Ma J Schlenk RF Rubnitz JE Döhner K Döhner H Downing JR 《Blood》2012,119(10):e67-e75
To identify cooperating lesions in core-binding factor acute myeloid leukemia, we performed single-nucleotide polymorphism-array analysis on 300 diagnostic and 41 relapse adult and pediatric leukemia samples. We identified a mean of 1.28 copy number alterations per case at diagnosis in both patient populations. Recurrent minimally deleted regions (MDRs) were identified at 7q36.1 (7.7%), 9q21.32 (5%), 11p13 (2.3%), and 17q11.2 (2%). Approximately one-half of the 7q deletions were detectable only by single-nucleotide polymorphism-array analysis because of their limited size. Sequence analysis of MLL3, contained within the 7q36.1 MDR, in 46 diagnostic samples revealed one truncating mutation in a leukemia lacking a 7q deletion. Recurrent focal gains were identified at 8q24.21 (4.7%) and 11q25 (1.7%), both containing a single noncoding RNA. Recurrent regions of copy-neutral loss-of-heterozygosity were identified at 1p (1%), 4q (0.7%), and 19p (0.7%), with known mutated cancer genes present in the minimally altered region of 1p (NRAS) and 4q (TET2). Analysis of relapse samples identified recurrent MDRs at 3q13.31 (12.2%), 5q (4.9%), and 17p (4.9%), with the 3q13.31 region containing only LSAMP, a putative tumor suppressor. Determining the role of these lesions in leukemogenesis and drug resistance should provide important insights into core-binding factor acute myeloid leukemia. 相似文献
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Background
Iron metabolism during pregnancy maintains fetal iron levels at the expense of the mother. The mechanism behind this regulation is still not clear despite recent advances. Here we examine the role of maternal and fetal Hfe, its downstream signaling molecule, hepcidin and dietary iron in the regulation of placental iron transfer.Design and Methods
Hfe wild-type, knockout and heterozygote dams were fed iron deficient (12.5 ppm), adequate (50 ppm) and replete (150 ppm) iron diets and mated with heterozygote males to produce pups of all genotypes. Dams and pups were sacrificed at Day 18 of gestation; serum, placenta, body and liver iron parameters were measured. Protein and mRNA levels of various iron transporter genes were determined in duodenum, liver and placenta by Western blotting and real time PCR.Results
Maternal liver iron levels were dependent on both dietary iron intake and Hfe genotype. Increasing iron levels in the maternal diet resulted in increased total iron in the fetus, primarily in the liver. However, fetuses of Hfe-knockout mothers showed further elevation of liver iron levels, concomitant with elevated expression of Tfr1, Dmt1 and Fpn in the placenta. Hfe-knockout fetuses that express low levels of liver hepcidin accumulated more iron in their liver than wild-type fetuses due to increased ferroportin levels in the placenta.Conclusions
Maternal and fetal status, as well as dietary iron, is important in regulating iron transfer across placenta. Maternal Hfe regulates iron transfer by altering gene expression in the placenta. Fetal Hfe is important in regulating placental iron transfer by modulating fetal liver hepcidin expression. 相似文献66.
Autoimmune thrombocytopenic purpura (ITP) is characterized by an abnormally low platelet count and bleeding risks. The exact triggering event remains elusive. Oxidative stress may play a role in several autoimmune diseases. A direct link between platelets in ITP and oxidative stress has not yet been addressed. The intracellular platelet antioxidant capacity (AOC) in ITP patients in the active phase (n?=?24) and remission (n?=?12), and 44 healthy controls were analysed with 2',7'-dichlorodihydrofluorescein diacetate, and in combination with hydrogen peroxide. Enzyme activities (EA) of serum glutathione peroxidase (GPx), glutathione reductase (GRed) and catalase (CAT) were investigated colourimetrically in patients and controls. The AOC of ITP patients in the active phase was drastically reduced, with significantly high mean fluorescence intensity values. Higher GPx activity was observed in both active phase and remission in comparison to healthy controls (p?0.001), with greater activity observed in active ITP than remission (p?=?0.001). However, GRed EA was not elevated indicating that reduced glutathione (GSH) is not comparably recovered as consumed, leading to a decreased bioavailability of GSH and increased oxidative stress. These results suggest that oxidative stress is implicated in active ITP and may play a crucial role in its pathophysiology. 相似文献
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Gina Shetty BS Georgia M. Beasley MD Sara Sparks BS MT ASCP Michael Barfield MD Melanie Masoud BS Paul J. Mosca MD PhD Scott K. Pruitt MD PhD April K. S. Salama MD Cliburn Chan MD PhD Douglas S. Tyler MD Kent J. Weinhold PhD 《Annals of surgical oncology》2013,20(4):1128-1135
Background
Preprocedure clinical and pathologic factors have failed to consistently differentiate complete response (CR) from progressive disease (PD) in patients after isolated limb infusion (ILI) with melphalan for unresectable in-transit extremity melanoma.Methods
Multiplex immunobead assay technology (Milliplex MAP Human Cytokine/Chemokine Magnetic Bead Panel, Millipore Corp., Billerica, MA; and Magpix analytical test instrument, Luminex Corp., Austin, TX) was performed on pre-ILI plasma to determine concentrations of selected cytokines (MIP-1α, IL-1Rα, IP-10, IL-1β, IL-1α, MCP-1, IL-6, IL-17, EGF, IL-12p40, VEGF, GM-CSF, and MIP-1β) on a subset of patients (n = 180) who experienced CR (n = 23) or PD (n = 24) after ILI. Plasma from normal donors (n = 12) was also evaluated.Results
Of 180 ILIs performed, 28 % (95 % confidence interval 22–35, n = 50) experienced a CR, 14 % (n = 25) experienced a partial response, 11 % (n = 21) had stable disease, 34 % (n = 61) had PD, and 13 % (n = 23) were not evaluable for response. Tumor characteristics and pharmacokinetics appeared similar between CR (n = 23) and PD (n = 24) patients who underwent cytokine analysis. Although there were no differences in cytokine levels between CR and PD patients, there were differences between the melanoma patients and controls. MIP-1α, IL-1Rα, IL-1β, IL-1α, IL-17, EGF, IL-12p40, VEGF, GM-CSF, and MIP-1β were significantly higher in normal controls compared to melanoma patients, while IP-10 was lower (p < 0.001) in controls compared to melanoma patients.Conclusions
Patients with unresectable in-transit melanoma appear to have markedly decreased levels of immune activating cytokines compared to normal healthy controls. This further supports a potential role for immune-targeted therapies and immune monitoring in patients with regionally advanced melanoma. 相似文献70.
Sally Abou Taleb Asmaa Badawy Darwish Amira Abood Amany M. Mohamed 《Drug development research》2020,81(3):374-388
The main goal of this study was to prepare and evaluate nanosponges containing ciprofloxacin (CIP) or its binary mixture with N-acetyl carnosine (NAC). Nanosponges were prepared by ultrasound-assisted synthesis technique using hydroxypropyl βeta-cyclodextrin (HPβ-CD), as the polymer and diphenyl carbonate (DPC) as the crosslinker. Entrapment efficiency (EE%) of CIP or its binary mixture with NAC in nanosponges was deduced spectrophotometrically. Nanosponges were characterized using several methods. EE% of CIP or its binary mixture with NAC inside nanosponges ranged from 98.63 ± 3.1 to 100 ± 0.07%. Particle size of nanosponges ranged from 66.7 to 90.1 nm. Release of drugs from nanosponges was biphasic and the release pattern followed Korsmeyer–Peppas model. Ex vivo and in vivo studies results showed that the antibacterial effect was enhanced with encapsulation of drugs in the nanosponge system. Furthermore, a potent antifungal activity was obtained from all examined formulae against Candida albicans (10231). The study revealed that successful encapsulation of CIP or its binary mixture with NAC in nanosponge formulations has innovated a new promising therapeutic activity for both drugs. 相似文献