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991.
992.
Frits van Rhee Yin-Zheng Jiang Faye Vigue Martha Kirby Dimitrios Mavroudis Nancy F. Hensel Vaishali Agarwala Emmanuel Clave Richard Childs Anastasios Raptis Elaine Sloand Charles Carter Elizabeth J. Read & John Barrett 《British journal of haematology》1999,105(4):1014-1024
To investigate mechanisms of stem cell graft rejection we studied the allo-stimulatory potential of G-CSF mobilized peripheral blood progenitor cells (PBPC). CD34+ cells were purified (>95%) in a two-step procedure using immunoaffinity columns for CD34 selection and T-depletion. The capacity of CD34+ cells to stimulate allogeneic T-cell responses was compared with other cells from the same individual. CD34+ cells induced potent proliferative responses at stimulator:responder ratios of 1:20, but were approximately 50-fold less efficient compared to dendritic cells. Furthermore, CD34+ cells primed responses from partially matched allogeneic T cells in bulk cultures. Dual-colour flow cytometry showed that the co-stimulatory molecules B7.1, CD40 and ICAM-1 were absent on resting CD34-positive progenitor cells, but were induced during incubation with allogeneic lymphocytes due to a cytokine-mediated effect. Up-regulation of accessory molecules on CD34+ cells was reproduced by incubation with interferon-gamma or GM-CSF which enhanced the allo-stimulatory activity of CD34+ cells. Blocking studies with inhibitory antibodies suggested co-stimulatory functions for B7.2, ICAM-3, CD40 and LFA-3. CD34+ cells were more efficient in inducing allogeneic T-cell responses when compared to the unprocessed leukapheresis products. The reduced allo-stimulatory ability of G-CSF mobilized PBPC could be explained by the presence of CD3+ 4+ and CD3+ 8+ lymphocytes with suppressor activity. We conclude that current methods of stem cell selection for transplantation do not avoid allosensitization of the recipient and that further graft manipulation with add-back of lymphocytes or selection of subsets of CD34+ cells with reduced allo-stimulatory ability may reduce graft rejection. 相似文献
993.
Da Woon Kim Hakeong Jeon Sungmi Kim Wanhee Lee Hyo Jin Kim Harin Rhee Sang Heon Song Eun Young Seong 《Medicine》2021,100(43)
Rationale:Focal segmental glomerulosclerosis (FSGS) is the most common primary glomerular disorder that leads to end-stage kidney disease. Pembrolizumab, an immune checkpoint inhibitor, is an anti-programmed death 1 (PD-1) immunoglobulin G4 antibody approved for the treatment of advanced melanoma and can cause various renal immune-related adverse events (AEs), including acute kidney injury. Several cases of anti PD-1 therapy-induced glomerulonephritis have been reported so far, but FSGS has seldom been reported.Patient concerns:46-year old woman presented to our hospital with generalized edema.Diagnoses:Laboratory examination revealed features of nephrotic syndrome, and kidney biopsy confirmed FSGS. After other etiological factors of secondary FSGS were ruled out, she was diagnosed with FSGS caused by pembrolizumab.Interventions:She did not resume treatment with pembrolizumab and was treated with irbesartan and furosemide according to the American Society of Clinical Oncology Practice guidelines.Outcomes:After 2 months, the features of nephrotic syndrome resolved.Lessons:This case provides valuable insight into the etiology of FSGS that can occur as a renal immune-related AE of PD-1 inhibitor therapy. Therefore, patients should undergo evaluation for renal function and urinalysis at baseline and after treatment. If patients treated with PD-1 inhibitors present with renal injury and/or unexplained proteinuria >1 g/day, we would recommend a kidney biopsy to determine the underlying cause and establish an appropriate therapeutic plan. 相似文献
994.
Major aneuploidies diagnosed prenatally involve the autosomes 13, 18, and 21, and sex chromosomes. Fluorescence in situ hybridization (FISH) allows rapid analysis of chromosome copy number in interphase cells. The purpose of this study was to evaluate the role of multicolor fluorescence in situ hybridization in simultaneous detection of probe sets for chromosome 18, X, and Y in uncultured amniotic fluid cells as a safer alternative method for aneuploidy detection prenatally. Fifty amniotic fluid samples were analyzed by FISH and standard cytogenetics. Mean time to obtain results was three days for fluorescence in situ hybridization and 20 days for karyotype. Fluorescence in situ hybridization was informative in 43 samples (86%), and within this group, two aneuploidies were correctly identified. This evaluation demonstrates that FISH with X, Y, and 18 alpha satellite DNA probes could accurately and rapidly detect aneuploidies involving these chromosomes and could be used in any prenatal clinical laboratory. 相似文献
995.
996.
Yoo EA Kim SD Lee WM Park HJ Kim SK Cho JY Min W Rhee MH 《Phytotherapy research : PTR》2008,22(10):1389-1395
Aloe species are traditionally prescribed for hypertension, burning, and rheumatoid arthritis. To elucidate the mechanism of the antihypertensive and anti-inflammatory activities of this herb, the ethanol fraction from A. saponaria Haw. was evaluated for antioxidative activity using xanthine-xanthine oxidase (XO) assay, 2,2-Diphenyl-lpicrylhydrazyl radical (DPPH) assay, lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cell, and antinociceptive activity using a tail-flick assay and hind paw pressure assay in cisplatin-treated hyperalgesic rats. The ethanol fraction displayed potent antioxidative activities in XO assay. In addition, ethanol fractions showed potent scavenging effects in DPPH assay. We next examined whether ethanol fractions showed anti-inflammatory activities. Ethanol fractions significantly suppressed NO production from LPS-activated RAW264.7 cells. As expected, ethanol fractions dose-dependently inhibited the messenger RNA expression of inducible NO synthase (iNOS). Moreover, ethanol fractions potently suppressed the expression of cycloxygenase (COX)-2 and granulocyte-macrophage colony-stimulating factor (GM-CSF), which are stimulated by LPS in RAW264.7 cells. In addition, ethanol fractions significantly blocked cisplatin-induced hyperalgesia using tail-flick assay and hind paw pressure test in rats. Taken altogether, ethanol extracts of aloe may be useful as a functional food or as a drug against reactive oxygen species (ROS) mediated diseases. 相似文献
997.
Incorporating bortezomib into upfront treatment for multiple myeloma: early results of total therapy 3 总被引:3,自引:0,他引:3
Barlogie B Anaissie E van Rhee F Haessler J Hollmig K Pineda-Roman M Cottler-Fox M Mohiuddin A Alsayed Y Tricot G Bolejack V Zangari M Epstein J Petty N Steward D Jenkins B Gurley J Sullivan E Crowley J Shaughnessy JD 《British journal of haematology》2007,138(2):176-185
Total therapy 3 incorporated bortezomib into a melphalan-based tandem transplant regimen for 303 newly diagnosed patients with myeloma. Induction chemotherapy prior to and consolidation chemotherapy after transplants each consisted of two cycles of VTD-PACE (bortezomib, thalidomide, dexamethasone and 4-d continuous infusions of cis-platin, doxorubicin, cyclophosphamide, etoposide); 3-year maintenance comprised monthly cycles of VTD in the first and TD in the remaining years. The median age was 59 years (age >64 years, 28%). A minimum of 20 x 10(6) CD34 cells/kg was collected in 87% of patients; 83% completed both transplants, and only 5% suffered a treatment-related death. At 24 months, 83% had achieved near-complete remission, which was sustained in 88% at 2 years from its onset. With a median follow-up of 20 months, 2-year estimates of event-free and overall survival were 84% and 86% respectively. The 44 patients who experienced an event more often had a high-risk gene array profile, cytogenetic abnormalities and indicators of high lactate dehydrogenase, beta-2-microglobulin, creatinine and International Staging System stage. Toxicities of grade > 2 included thrombo-embolic events in 27% and peripheral neuropathy in 12%. Results of this phase-2 study demonstrated that bortezomib could be safely combined with multi-agent chemotherapy, effecting near-complete remission status and 2-year survival rates in more than 80% of patients. 相似文献
998.
Jae‐Hwan Lee MD PhD Hyun‐Sook Kim MD PhD Seung‐Whan Lee MD PhD Jae‐Hyeong Park MD PhD Si‐Wan Choi MD PhD Jin‐Ok Jeong MD PhD Yoonhaeng Cho MD Naehee Lee MD PhD Kyoung‐Suk Rhee MD PhD Jae‐Ki Ko MD PhD In‐Whan Seong MD PhD 《Catheterization and cardiovascular interventions》2008,72(1):25-32
Objective: The aim of this study was to compare effectiveness of the Sirolimus‐ (SES) and Paclitaxel‐eluting stent (PES) in primary angioplasty for acute ST‐elevation myocardial infarction (STEMI). Background: It has been reported that SES and PES have been more effective than bare‐metal stents in reducing restenosis and cardiac events in a broad range of patients with coronary artery disease. However, it is unknown whether there may be differences between these two drug‐eluting stents in terms of efficacy in the setting of acute STEMI. Methods: Acute STEMI patients (n = 308) undergoing primary angioplasty were randomly assigned to SES (n = 154) or PES (n = 154) deployment. The routine angiographic follow‐up was performed at 6 months and clinical follow‐up data was obtained at 12 months. The primary end point was major adverse cardiac events (MACE) including death, reinfarction, stent thrombosis, and target lesion revascularization (TLR) at 12 months. Results: The baseline clinical, angiographic, and procedural characteristics were similar between the 2 groups. Two patients (all from the PES group) experienced stent thrombosis (1 acute and 1 subacute). The SES group revealed lower in‐segment restenosis (5.9% vs. 14.8%, P = 0.03) and in‐segment late loss (0.09 ± 0.45 vs. 0.33 ± 0.68 mm, P = 0.002) than PES group on follow‐up angiography. Twelve‐month TLR rates (2.6% vs. 6.5%, P = 0.17) were similar between two groups. MACE rates were lower in the SES group than in the PES group, but it did not reach statistical significance (5.8% vs. 11.7%, P = 0.07). Conclusion: In the setting of primary angioplasty for STEMI, there were no statistically significant differences between the SES and the PES in terms of 12‐month MACE. However, binary angiographic in‐segment restenosis and in‐segment late loss were significantly lower in the SES group. © 2008 Wiley‐Liss, Inc. 相似文献
999.
Genetic and functional confirmation of the causality of the DGAT1 K232A quantitative trait nucleotide in affecting milk yield and composition 总被引:17,自引:0,他引:17
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Grisart B Farnir F Karim L Cambisano N Kim JJ Kvasz A Mni M Simon P Frère JM Coppieters W Georges M 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(8):2398-2403
We recently used a positional cloning approach to identify a nonconservative lysine to alanine substitution (K232A) in the bovine DGAT1 gene that was proposed to be the causative quantitative trait nucleotide underlying a quantitative trait locus (QTL) affecting milk fat composition, previously mapped to the centromeric end of bovine chromosome 14. We herein generate genetic and functional data that confirm the causality of the DGAT1 K232A mutation. We have constructed a high-density single-nucleotide polymorphism map of the 3.8-centimorgan BULGE30-BULGE9 interval containing the QTL and show that the association with milk fat percentage maximizes at the DGAT1 gene. We provide evidence that the K allele has undergone a selective sweep. By using a baculovirus expression system, we have expressed both DGAT1 alleles in Sf9 cells and show that the K allele, causing an increase in milk fat percentage in the live animal, is characterized by a higher Vmax in producing triglycerides than the A allele. 相似文献
1000.
Chan JM Rhee JW Drum CL Bronson RT Golomb G Langer R Farokhzad OC 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(48):19347-19352
Following recent successes with percutaneous coronary intervention (PCI) for treating coronary artery disease (CAD), many challenges remain. In particular, mechanical injury from the procedure results in extensive endothelial denudation, exposing the underlying collagen IV-rich basal lamina, which promotes both intravascular thrombosis and smooth muscle proliferation. Previously, we reported the engineering of collagen IV-targeting nanoparticles (NPs) and demonstrated their preferential localization to sites of arterial injury. Here, we develop a systemically administered, targeted NP system to deliver an antiproliferative agent to injured vasculature. Approximately 60-nm lipid-polymeric NPs were surface functionalized with collagen IV-targeting peptides and loaded with paclitaxel. In safety studies, the targeted NPs showed no signs of toxicity and a ≥3.5-fold improved maximum tolerated dose versus paclitaxel. In efficacy studies using a rat carotid injury model, paclitaxel (0.3 mg/kg or 1 mg/kg) was i.v. administered postprocedure on days 0 and 5. The targeted NP group resulted in lower neointima-to-media (N/M) scores at 2 wk versus control groups of saline, paclitaxel, or nontargeted NPs. Compared with sham-injury groups, an ~50% reduction in arterial stenosis was observed with targeted NP treatment. The combination of improved tolerability, sustained release, and vascular targeting could potentially provide a safe and efficacious option in the management of CAD. 相似文献