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11.
Serum concentrations of the thrombopoiesis-enhancing cytokines thrombopoietin (TPO), erythropoietin (EPO), interleukin (IL)-6 and IL-11 were determined in 119 healthy whole-blood (WBD) and 101 platelet donors (PD) prior to donation. The 90% TPO reference interval in WBD of 64-867 pg/ml (median 163, 100% range 45-7572) was significantly higher than in PD of 56-524 (median 122, range 44-801, P = 0.004), whereas their platelet counts were lower (P < 0.001). EPO levels were not different (WBD 7.7 +/- 3.8, PD 8.0 +/- 4.9 IU/l), IL-6 and IL-11 were below the detection limit in >/=90% of cases (IL-6 < 3.2 pg/ml, IL-11 < 31.2 pg/ml). None of the cytokines correlated with platelet counts, other blood parameters, or in the PD group with the frequency of platelet donations within the last 6 months. We conclude that plateletpheresis does not lead to a lasting increase of thrombopoietic cytokines and provide reference data for potential platelet mobilization strategies with recombinant growth factors.  相似文献   
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Paying for blood donations: still a risk?   总被引:4,自引:0,他引:4  
It is presently disputed whether studies indicating a higher risk of infectious diseases among paid blood donors are lessons of the past, or still hold relevance. Comparative studies published between 1968 and 2001 were assessed for a possible trend of change in the relative risk for infectious disease markers between paid and unpaid blood or plasma donors. Studies reporting that paid donors had lower risk were found, but most studies, including recent ones, continued to report that paid donors have higher rates of infectious disease markers than unpaid donors. By log-linear regression analysis of the relative risk estimates for infectious disease markers among paid and unpaid donors from 28 published data sets, evidence was not found to indicate that the difference in risk for infectious disease markers between paid donors and unpaid donors had diminished over time (P = 0.128, not significant). Paid donors are still more likely than unpaid donors to donate blood in the period during which infectious donations escape detection by blood-screening tests (the "window-period"). Therefore, paid donations have a higher risk that labile blood components (such as red blood cells and platelets) are infected. Additional safety measures for handling plasma donations, and the preparation, purification and viral-inactivation steps employed for the production of plasma derivatives, may render the difference in infectious disease marker rates in donors irrelevant for plasma products. However, not all viruses are inactivated and paid donors were repeatedly found to have higher frequencies of markers for emerging agents. In a quality system, critical steps of the process should be addressed, and selection of the donor population is one of the first steps in this process. It is advised that blood establishments present yearly reports (with complete and raw data) to authorities on the incidence and prevalence of infectious disease markers among their donors as an ongoing surveillance on the "quality" of their donor populations. Paid blood or plasma donors still have higher rates for infectious disease markers than unpaid donors.  相似文献   
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Microsatellite stable (MSS), CpG island methylator phenotype (CIMP)‐negative colorectal tumors, the most prevalent molecular subtype of colorectal cancer, are associated with extensive copy number alteration (CNA) events and aneuploidy. We report on the identification of characteristic recurrent CNA (with frequency >25%) events and associated gene expression profiles for a total of 40 paired tumor and adjacent normal colon tissues using genome‐wide microarrays. We observed recurrent CNAs, namely gains at 1q, 7p, 7q, 8p12‐11, 8q, 12p13, 13q, 20p, 20q, Xp, and Xq and losses at 1p36, 1p31, 1p21, 4p15‐12, 4q12‐35, 5q21‐22, 6q26, 8p, 14q, 15q11‐12, 17p, 18p, 18q, 21q21‐22, and 22q. Within these genomic regions we identified 356 genes with significant differential expression (P < 0.0001 and ±1.5‐fold change) in the tumor compared to adjacent normal tissue. Gene ontology and pathway analyses indicated that many of these genes were involved in functional mechanisms that regulate cell cycle, cell death, and metabolism. An amplicon present in >70% of the tumor samples at 20q11‐20q13 contained several cancer‐related genes (AHCY, POFUT1, RPN2, TH1L, and PRPF6) that were upregulated and demonstrated a significant linear correlation (P < 0.05) for gene dosage and gene expression. Copy number loss at 8p, a CNA associated with adenocarcinoma and poor prognosis, was observed in >50% of the tumor samples and demonstrated a significant linear correlation for gene dosage and gene expression for two potential tumor suppressor genes, MTUS1 (8p22) and PPP2CB (8p12). The results from our integration analysis illustrate the complex relationship between genomic alterations and gene expression in colon cancer. © 2013 Wiley Periodicals, Inc.  相似文献   
14.
BackgroundConvalescent plasma is one of the treatment options for COVID-19 which is currently being investigated in many clinical trials. Understanding of donor and product characteristics is important for optimization of convalescent plasma.MethodsPatients who had recovered from CO­VID-19 were recruited as donors for COVID-19 convalescent plasma (CCP) for a randomized clinical trial of CCP for treatment of severe COVID-19 (CAPSID Trial). Titers of neutralizing antibodies were measured by a plaque-reduction neutralization test (PRNT). Correlation of antibody titers with host factors and evolution of neutralizing antibody titers over time in repeat donors were analysed.ResultsA series of 144 donors (41% females, 59% males; median age 40 years) underwent 319 plasmapheresis procedures providing a median collection volume of 850 mL and a mean number of 2.7 therapeutic units per plasmapheresis. The majority of donors had a mild or moderate course of COVID-19. The titers of neutralizing antibodies varied greatly between CCP donors (from <1:20 to >1:640). Donor factors (gender, age, ABO type, body weight) did not correlate significantly with the titer of neutralizing antibodies. We observed a significant positive correlation of neutralization titers with the number of reported COVID-19 symptoms and with the time from SARS-CoV-2 diagnosis to plasmapheresis. Neutralizing antibody levels were stable or increased over time in 58% of repeat CCP donors. Mean titers of neutralizing antibodies of first donation and last donation of repeat CCP donors did not differ significantly (1:86 at first compared to 1:87 at the last donation). There was a significant correlation of neutralizing antibodies measured by PRNT and anti-SARS-CoV-2 IgG and IgA antibodies which were measured by ELISA. CCP donations with an anti-SARS-CoV-2 IgG antibody content above the 25th percentile were substantially enriched for CCP donations with higher neutralizing antibody levels.ConclusionWe demonstrate the feasibility of collection of a large number of CCP products under a harmonized protocol for a randomized clinical trial. Titers of neutralizing antibodies were stable or increased over time in a subgroup of repeat donors. A history of higher number of COVID-19 symptoms and higher levels of anti-SARS-CoV-2 IgG and IgA antibodies in immunoassays can preselect donations with higher neutralizing capacity.  相似文献   
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OBJECTIVE: Addison's disease is associated with particular haplotypes of the human leucocyte antigen (HLA) region [DQA1*0501-DQB1*0201 (DQ2) and DQA1*0301-DQB1*0302 (DQ8)]. This locus harbours several human endogenous retroviral (HERV) long-terminal repeats (LTR). LTRs within the HLA region have been shown to confer additional susceptibility to type 1 diabetes and rheumatoid arthritis. DESIGN: We investigated the role of LTR3 and LTR13, both of which are located adjacent to the DQB1 gene, in Addison's disease. PATIENTS: Eighty-seven patients and 160 controls were genotyped for HLA-DQA, -DQB, and the presence or absence of LTR3 and LTR13. RESULTS: Significantly more patients' HLA alleles than those of controls carried the LTR13 insertion (19.0% vs. 10.6%, P = 0.0143), whereas there was only a trend for LTR3 (allele-wise chi-squared test: P = 0.0941). Both, LTR3 and LTR13 are in strong linkage disequilibrium with DQ8, which itself was significantly more frequent in patients than in controls (29.9% vs. 15.0%, P = 0.0089). However, significantly more alleles of DQ8+ patients than of DQ8+ controls carried the LTR13 insertion (44.2% vs. 18.8%, P = 0.0119), whereas we did not observe any difference for LTR3 in the DQ8+ subset (30.5 vs. 23.1%, P = 0.9416). CONCLUSIONS: We have found preliminary evidence that the endogenous retroviral element DQ-LTR13, but not LTR3, is associated with Addison's disease. LTR13 appears to enhance HLA-DQ8 mediated disease risk. This retroviral insertion therefore might represent a novel susceptibility factor in Addison's disease, but these findings need to be confirmed in a larger data set.  相似文献   
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BACKGROUND: Growth hormone (GH) may be associated with the development of colorectal tumors directly and/or indirectly via an increased plasma level of insulin-like growth factor-I (IGF-I), which has been associated with colorectal cancer risk. Because a T-to-A polymorphism in the human GH1 gene at position 1663 is putatively associated with lower levels of GH and IGF-I, we investigated the relationship of this polymorphism to the risk of colorectal neoplasia. METHODS: We analyzed data from two case-control studies conducted in Hawaii: a population-based study of 535 case patients with colorectal adenocarcinoma and 650 control subjects and a sigmoidoscopy screening-based study with 139 case patients with adenoma and 202 control subjects. All subjects were tested for the GH1 polymorphism. Logistic regression was used to adjust for known risk factors. Plasma IGF-I and IGF binding protein-3 (IGFBP-3) levels were measured in a subset of 293 subjects in the adenoma study (135 case patients and 158 control subjects). All statistical tests were two-sided. RESULTS: Adjusted odds ratios (ORs) for colorectal cancer associated with T/T, T/A, and A/A genotypes were 1.00, 0.75 (95% confidence interval [CI] = 0.58 to 0.99), and 0.62 (95% CI = 0.43 to 0.90), respectively (P(trend) =.006). Adjusted ORs for adenoma were 1.00, 0.76 (95% CI = 0.46 to 1.24), and 0.62 (95% CI = 0.31 to 1.22), respectively (P(trend) =.17). Data from both studies consistently showed that the A allele was associated with a lower risk of colorectal neoplasia than the T allele, although the association with adenoma was not statistically significant. These associations were consistently suggested in Caucasians and Native Hawaiians but not in Japanese. The ratio of plasma IGF-I/IGFBP-3 was lower in individuals with the A allele than in individuals with the T allele (P =.01). CONCLUSION: The human T1663A GH1 gene polymorphism, which may confer lower levels of GH and IGF-I, appears to be associated with a decreased risk of colorectal cancer.  相似文献   
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