Warm red blood cell autoantibodies and clinical diagnoses in patients with or without autoimmune hemolysis.

OBJECTIVES: Red blood cell autoantibodies (RBC autoAbs) of IgG class are found in the majority of patients with warm autoimmune hemolytic anemia (wAIHA) but sometimes also during the pretransfusion testing of patients with different diagnoses but without hemolysis. The aim of the study was to identify the main differences between these two groups of patients according to age, gender, subclass and titer of IgG RBC autoAbs and diagnosis. MATERIAL AND METHODS: In the 9-year retrospective study, data were collected from records of 291 patients with IgG RBC autoAbs detected by gel technique, from which 111 with wAIHA. RESULTS: More than 85% of patients in both groups were over 40 years old, with male to female ratio 1:1.9 in wAIHA vs 1:1.3 in patients without hemolysis (P=0.0916). The main characteristics of patients with wAIHA vs patients without hemolysis were: IgG only 38% vs 70%, IgG+Complement 62% vs 30%, total IgG1 79% vs 55%, IgG1+IgG3 35% vs 11%, titer of 100 for IgG1+IgG3 17% vs 3% (P<0.0001), respectively, while titer of 100 for IgG1 18% vs 9% (P=0.0241). The underlying diagnosis in wAIHA vs patients without hemolysis: hematologic disorders 41% vs 22% (P=0.0006), autoimmune disorders 12% vs 13% (P=0.8033), solid tumors 5% vs 14% (P=0.0154) and surgery procedures 6% vs 26% (P<0.0001). CONCLUSION: We observed more wAIHA patients with high titer of IgG1 and high prevalence of IgG1+IgG3 and consider that patients without hemolysis having identical results might be interesting to find out how they are protected from damage by RBC autoAbs.

GIS-based probability assessment of natural hazards in forested landscapes of Central and South-Eastern Europe.

We assessed the probability of three major natural hazards--windthrow, drought, and forest fire--for Central and South-Eastern European forests which are major threats for the provision of forest goods and ecosystem services. In addition, we analyzed spatial distribution and implications for a future oriented management of forested landscapes. For estimating the probability of windthrow, we used rooting depth and average wind speed. Probabilities of drought and fire were calculated from climatic and total water balance during growing season. As an approximation to climate change scenarios, we used a simplified approach with a general increase of pET by 20%. Monitoring data from the pan-European forests crown condition program and observed burnt areas and hot spots from the European Forest Fire Information System were used to test the plausibility of probability maps. Regions with high probabilities of natural hazard are identified and management strategies to minimize probability of natural hazards are discussed. We suggest future research should focus on (i) estimating probabilities using process based models (including sensitivity analysis), (ii) defining probability in terms of economic loss, (iii) including biotic hazards, (iv) using more detailed data sets on natural hazards, forest inventories and climate change scenarios, and (v) developing a framework of adaptive risk management.

Characterization of a novel DNA binding domain within the amino-terminal region of the RAG-1 protein.

Rag-1 and Rag-2 are the critical components of the V-(D)-J recombinase required for site-specific recombination of the antigen receptor genes. In this study, we have examined the ability of recombinant (r) Rag-1 and Rag-2 to bind the recombination signal sequences (RSS) and have determined that rRag-1, but not rRag-2, is able to directly bind DNA. rRAG-1 DNA binding activity was found to reside within a novel amino-terminal arginine-rich (RR) domain with partial homology to a variety of nucleic acid binding domains. Although the RR-domain did not demonstrate RSS-specificity, this DNA binding domain may stabilize the interaction of RAG-1 with, or increase the affinity for, the V-(D)-J recombination signals.

Regulation of the RAG-1 promoter by the NF-Y transcription factor.

We have cloned the RAG-1 promoter region and have determined that almost all detectable promoter activity resides within a 208-bp fragment. Sequence analysis of this promoter region has identified potential recognition motifs for a number of lymphocyte-restricted and ubiquitous transcription factors. Subsequent assays have revealed that the NF-Y transcription factor interacts with a CCAAT site within the RAG-1 promoter and appears to play an important role in the positive transcriptional regulation of this gene.