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91.
Bovine viral diarrhea virus (BVDV) infection during early gestation results in persistently infected (PI) immunotolerant calves that are the primary reservoirs of the virus. Pathologies observed in PI cattle include congenital defects of the brain, heart, and bone as well as marked functional defects in their immune system. It was hypothesized that fetal BVDV infection alters T cell activation and signaling genes by epigenetic mechanisms. To test this, PI and control fetal splenic tissues were collected on day 245 of gestation, 170 days post maternal infection. DNA was isolated for reduced representation bisulfite sequencing, protein was isolated for proteomics, both were analyzed with appropriate bioinformatic methods. Within set parameters, 1951 hypermethylated and 691 hypomethylated DNA regions were identified in PI compared to control fetuses. Pathways associated with immune system, neural, cardiac, and bone development were associated with heavily methylated DNA. The proteomic analysis revealed 12 differentially expressed proteins in PI vs. control animals. Upregulated proteins were associated with protein processing, whereas downregulated proteins were associated with lymphocyte migration and development in PI compared to control fetal spleens. The epigenetic changes in DNA may explain the immune dysfunctions, abnormal bone formation, and brain and heart defects observed in PI animals.  相似文献   
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Fanconi anaemia (FA) is a genetically heterogeneous disease with at least eight complementation groups (A-H). In the present study, we investigated the molecular basis of the disease in 13 unrelated Israeli Jewish (non-Ashkenazi) patients with FA. All 43 exons of the Fanconi anaemia A (FANCA) gene were amplified from genomic DNA and screened for mutations by single-strand conformation polymorphism and DNA sequencing. We identified four ethnic-specific mutations: (1) 2172-2173insG (exon 24), the first 'Moroccan mutation': (2) 4275delT (exon 43), the second 'Moroccan mutation'; (3) 890-893del (exon 10), the 'Tunisian mutation'; and (4) 2574C > G (S858R), the 'Indian mutation'. The tetranucleotide CCTG motif, previously identified as a mutation hotspot in FANCA and other human genes, was found in the vicinity of 2172-2173insG and 890-893del. According to our study, the four mutations account for the majority (88%) of the FANCA alleles in the Israeli Jewish (non-Ashkenazi) FA population. A screening of 300 Moroccan Jews identified three carriers of the first 'Moroccan mutation', but we did not find any carrier of the second 'Moroccan mutation' among 140 Moroccan Jews, nor any carrier of the 'Tunisian mutation' among 50 Tunisian Jews. Two 'Indian mutation' carriers were identified among 53 Indian Jews. All carriers within each ethnic group had the same haplotype, suggesting a common founder for each mutation.  相似文献   
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Congenital dyserythropoietic anaemia (CDA) type I is a rare, inherited disorder characterised by ineffective erythropoiesis and macrocytic anaemia. Complex bone disease has only occasionally been associated with this disease. CDA I is caused by mutations in the CDAN1 gene encoding for codanin-1. Our aim was to characterise the CDAN1 mutation in eight unrelated patients with sporadic CDA I, three of whom had complex bone disease. Six novel mutations in the CDAN1 gene were identified. In two patients, one mutation and in another, both mutations were elusive. No patient was homozygous for a null-type mutation. However, one patient with complex bone disease was homozygous for a splice-site mutation (IVS-12+5G>A). Western blotting revealed that codanin-1 synthesis was 65% less than the control. Five single nucleotide polymorphisms (SNPs) previously unreported in the literature or the SNP database were also identified. Although the absence of codanin-1 is probably lethal, the presence of 35% of the protein was compatible with life but was associated with severe clinical manifestations. However, in most patients studied, no correlation could be established between the expected levels of codanin-1 or the nature of the mutation and the severity of the clinical manifestations.  相似文献   
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Background: Though recent reports have indicated a higher prevalence of latent tuberculosis infection (LTBI) in laboratory personnel than in other healthcare workers, these studies included only a limited number of laboratory personnel. Methods: We have thus focused on the laboratory personnel, who had a high level of exposure to specimens from patients with TB. We recruited 173 laboratory personnel and performed QuantiFERON‐TB Gold In‐Tube test (QFT‐G) and tuberculin skin test (TST). Results: QFT‐G was positive in 21.4% of the enrolled laboratory personnel, and TST was positive in 33.3%. The agreement between the two tests was fair (κ = 0.234). In multivariate analyses, household contactwith TBpatients (P = 0.013), the laboratory sections of microbiology (P = 0.045) and chemistry/immunology (P = 0.014) were shown to be significantly associated with positive QFT‐G results. Conclusion: Our data show a high prevalence of TST and QFT‐G positivity in laboratory personnel and emphasize the importance of LTBI screening for laboratory personnel. In BCG‐vaccinated populations with an intermediate incidence setting, QFT‐G seems to be superior to TST as a screening tool for the detection of LTBI. Further study, including results of follow‐up tests will be helpful for confirmation of our findings. J. Clin. Lab. Anal. 25:382–388, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
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BackgroundWhole blood viscosity (WBV) is the resistance of blood flow in blood vessels. Increased WBV may be a cardiovascular risk factor. The proper screening of WBV can help the early detection of cardiovascular disease. We investigated the performance of a new scanning capillary tube viscometer (SCTV) for the measurement of WBV.MethodsWe evaluated the total precision of the SCTV for 20 days using three control viscosity materials, and the within-day precision with the whole blood samples of three different individuals. For the linearity evaluation, serial dilutions of a high concentration standard material were used. For the method comparison, the results of the SCTV method were compared to those of Brookfield rotating viscometer on 227 subjects.ResultsThe SCTV had good within-run and total-run coefficient of variant (CV)s at low-, medium-, and high-concentration samples, at shear rates of 1 and 300 s? 1. The within-day CVs with the three human blood samples were 6.3%, 3.7% and 3.8% at a shear rate of 1 s? 1, and 3.2%, 3.0% and 4.1% at a shear rate of 300 s? 1. The SCTV method showed an excellent linearity in the range of 84.9 to 558.2 milliPoise (mP) and 28.8 to 71.0 mP at shear rates of 1 and 300 s? 1, respectively. For the comparison study, the SCTV and the rotating viscometer showed comparable results.ConclusionsThe SCTV showed a stable analytical performance, and was comparable with the rotational viscometer. This new SCTV method can be used in the clinical laboratory for various needs.  相似文献   
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