Evaluation of Serum Interleukin-21 and HLA-C1 Polymorphism in Pediatrician Hematopoietic Stem Cell Transplantation for Early Diagnosis of Acute Graft-Versus-Host Disease

Background: Allogenic hematopoietic stem cell transplantation (HSCT) is a strategy used for treatment of different malignant diseases. However, success of allo-HSCT can be hampered by graft-versus-host-disease (GVHD). Natural killer (NK) cells may play an important role in activating antigen presenting cells and subsequent activation of T cells. The main purpose of this study was the evaluation of IL-21, as a blood biomarker, for early detection of acute GVHD (aGVHD) in children after HSCT and also the study of human leukocytes antigen (HLA)-C1 polymorphism, as a targeting ligand for NK cells in these patients. Methods: Fifty one children receiving HSCT were studied. Blood samples were collected at -8, 7, and 14 days of transplantation. The -8-day samples were analyzed for HLA-C1 polymorphism by PCR-sequence-specific primer technique and pre-transplantation IL-21 assay. To study the serum levels of IL-21, two blood samples were collected on days +7 and +14 and analyzed by ELISA technique. Results: The results indicated that the incidence of aGVHD in pediatric is associated with a polymorphism of HLA-C1, as alleles HLA-C01:12 (P<0.001), HLA-C01:22 (P<0.004), and HLA-C01:67 (P<0.009). On the other hand, the serum levels of IL-21 in children with aGVHD were decreased after transplantation compared to before transplantation. The serum levels of the IL-21 at 14 days after transplantation had a significant correlation with the occurrence of aGVHD (P=0.05). Conclusion: Based on the findings of this study, there is a significant correlation between HLA-C1 polymorphisms and the serum levels of IL-21 with the incidence of aGVHD.

Emergencies in the air: problems, management, and prevention.

Medical emergencies may arise on board commercial airlines. Although infrequent, such events annually affect a substantial number of air travelers. Physicians should be aware of the options available to them should they find themselves in an emergency situation on an aircraft. This article examines the incidence of in-flight emergencies, surveys the onboard medical kit, and explores various in-flight medical problems and treatments. It concludes with a discussion of various methods of prevention.

SU-E-T-150: The Basic Dosimetric Properties of NIPAM Polymer Gel Dosimeter.

PURPOSE: To asses a series of basic dosimetric properties such as reproducibility, linearity, tissue equivalency, dose rate and energy independency for NIPAM polymer gel dosimeter. METHODS: The NIPAM gel was manufactured according to the method, described by senden et al (2006). The gels were irradiated approximately 2 h after manufacturing and MR images of the gel were made 24 h after irradiation. Transverse relaxation rates (R2=T2?1 ) were obtained from the signal decay data using the proper data analyzer. In order to investigate the absorbed dose response reproducibility, the experiment was repeated three times using the same batch of monomer, irradiation method, scanning parameters and conditions, also with analyzing two set of the gel with different batches of chemical the effect of different batches were investigated . For assessing if the NIPAM gel dosimeter response is dependent on different photon energies, two sets of NIPAM gel were irradiated using a 9 MV linear accelerator and a 60co. The effect of different dose rate on gel response was studied in SSD of 80, 90, 100, 110 and 120 and radiation beam were calibrated to give 5Gy in each SSD. To investigate the linearity of the gel, the vials were irradiated from 1 to 35 Gy. In order to verify tissue equivalency, effective atomic number and relative electron density of NIPAM dosimeter were calculated using CT number, and compared with tissue. RESULTS: This polymer gel found to be tissue equivalent. The results showed that the dose response of NIPAM polymer gel is highly reproducible in same and different batches of chemical and its response was linear up to 26 Gy. Energy and dose rate had no effect on NIPAM gel response. CONCLUSIONS: NIPAM gel dosimeter appears to be a promising dosimeter in all aspects of dosimetric properties which were assessed in this study.

Characterization of a multifunctional methyltransferase from the orchid Vanilla planifolia.

The final enzymatic step in the synthesis of the flavor compound vanillin (4-hydroxy-3-methoxybenzaldehyde) is believed to be methylation of 3,4-dihydroxybenzaldehyde. We have isolated and functionally characterized a cDNA that encodes a multifunctional methyltransferase from Vanilla planifolia tissue cultures that can catalyze the conversion of 3,4-dihydroxybenzaldehyde to vanillin, although 3,4-dihydroxybenzaldehyde is not the preferred substrate. The higher catalytic efficiency of the purified recombinant enzyme with the substrates caffeoyl aldehyde and 5-OH-coniferaldehyde, and its tissue distribution, suggest this methyltransferase may primarily function in lignin biosynthesis. However, since the enzyme characterized here does have 3,4-dihydroxybenzaldehyde-O-methyltransferase activity, it may be useful in engineering strategies for the synthesis of natural vanillin from alternate sources.