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Objective: Identification of plasma markers indicative for atrial fibrillation-associated silent brain lesions., Design and Methods: 1. Comparative determination of the plasma concentrations of secretagogin, S100B, neuropeptide Y, brain fatty acid binding protein, matrix metalloprotease 9, brain natriuretic peptide, and of D-Dimer in 222 patients with atrial fibrillation and 28 controls by immunoassays. 2. Correlation of the biochemical marker plasma concentration with the extent of silent white matter brain lesions, as determined by the Fazekas score and N-acetylaspartate-spectroscopy., Results: 1. Plasma concentrations of brain natriuretic peptide, of neuropeptide Y, and of matrix metalloprotease 9 were significantly higher (all with a p<0.05) in patients suffering from atrial fibrillation than in control subjects. 2. Brain natriuretic peptide correlated significantly with the Fazekas score (R=0.41; p<0.005). 3. Brain natriuretic peptide plasma concentrations were significantly higher in patients with a pathological N-acetylaspartate magnetic resonance-spectrometry (p<0.05)., Conclusion: Brain natriuretic peptide plasma concentrations correlate with the extent of atrial fibrillation-associated silent brain lesions.

Problem: Expression of heat shock proteins has been described in different tissues relevant to human reproduction, including placenta. AlphaB-crystallin is a member of the small heat shock protein family (sHsp) exerting biologically important chaperon functions., Method of Study: Immunofluorescence; immunoblot analysis; quantitative real-time-PCR; CpG island methylation analysis., Results: In this study, we once again describe the expression of alphaB-crystallin in the stroma of the placental villi and in the cytoplasm of decidual cells by immunofluorescence. In contrast, Hsp27--another sHsp family member--was detected exclusively in the syncytiotrophoblast layer. This varying expression pattern provides additional support to earlier reports of functional differences between both proteins. Semi-quantitative immunoblot analysis of placenta tissue specimens (n = 6) revealed Hsp27 expression exceeding that of alphaB-crystallin, albeit with interindividual variations. Inter-individual alphaB-crystallin expression variations were confirmed by quantitative RT-PCR. CpG island methylation was ruled out as the underlying cause for the inter-individual alphaB-crystallin expression variations. However, the expression extent of GATA3, which is a transcription factor with corresponding elements within the alphaB-crystallin gene (CRYAB) promoter, paralleled that of alphaB-crystallin. We demonstrated remarkable GATA3 expression in placental tissue, exceeding that of other endocrine organs., Conclusion: We can conclude that the differential expression patterns of alphaB-crystallin and Hsp27 indicate functional differences between these highly related proteins in placental tissues.

Expression of the small heat shock protein alphaB-crystallin in differentiated thyroid tumors has been described recently. In this study, we investigated the molecular mechanisms that affect the expression of alphaB-crystallin in benign goiters (n = 7) and highly malignant anaplastic thyroid carcinomas (ATCs) (n = 3). AlphaB-crystallin expression was compared with that of Hsp27-1. Immunoblot and quantitative real-time (RT) polymerase chain reaction revealed marked downregulation of alphaB-crystallin in all the tested ATCs and the ATC-derived cell line C-643 . In contrast, considerable expression of Hsp27-1 in benign and malignant thyroid tissue was demonstrated. Immunofluorescence analysis revealed no relevant topological differences between benign and malignant thyrocytes in the cytoplasmic staining of both proteins. Consistent and marked downregulation of TFCP2L1 was identified as one of the main mechanisms contributing to CRYAB gene silencing in ATCs. In addition, CRYAB gene promoter methylation seems to occur in distinct ATCs. In silico analysis revealed that the differential expression of alphaB-crystallin and Hsp27-1 results from differences between the alphaB-crystallin and Hsp27-1 promoter fragments (712 bp upstream from the transcriptional start site). Biological activity of the analyzed promoter element is confirmed by its heat shock inducibility. In conclusion, we demonstrate downregulation of alphaB-crystallin expression in highly dedifferentiated ATCs because of a tumor-specific transcription factor pattern. The differential expression of alphaB-crystallin and Hsp27-1 indicates functional differences between both proteins.

Multiple RET proto-oncogene transcripts, due to genomic variations and alternate splicing, have been described. To investigate endocrine tumor tissue characteristic RET proto-oncogene expression, we performed quantitative RT-PCR, Northern blot and Southern blot analyses of benign and malignant endocrine-derived tissues. We newly describe RET proto-oncogene expression in carcinoid-, gastrinoma- and insulinoma-derived tissue samples. In addition, the presence of a 3'-terminally truncated RET proto-oncogene mRNA variant in benign and malignant thyroid neoplasias, as well as in a pheochromocytoma, an ovarian carcinoma and a medullary thyroid carcinoma, is demonstrated. Southern blot analysis revealed no evidence of gross RET proto-oncogene rearrangements or deletions. As the underlying cause for a bi-allelic TaqI restriction fragment length polymorphism (RFLP), a C (allele 1)/T (allele 2) transition within intron 19, was characterized. This polymorphism is close to a recently described polyadenylation site and lies within a binding site for the nucleic acid binding protein Pbx-1. Screening of healthy subjects and of patients suffering from various endocrine malignancies revealed exclusively allele 1 homozygous and allele 1/allele 2 heterozygous genotypes. Heterozygous genotypes were found in a significantly higher percentage in samples derived from endocrine tumor patients when compared with those from healthy control subjects. Homozygosity for allele 2 was found exclusively in somatic DNA derived from endocrine tumors with high malignant potential. Analysis of DNA derived from varying regions within individual anaplastic thyroid carcinomas revealed an allele 1/allele 2 switch of the RFLP banding pattern, indicating loss of heterozygosity at the RET proto-oncogene locus. In conclusion, our data demonstrate presence of a 5'-terminal RET proto-oncogene transcript in endocrine tissues and reveal a bi-allelic RET proto-oncogene polymorphism. A heterozygous genotype for this polymorphism is found in a considerable number of endocrine tumor patients.

We describe two new variants of the recently identified hexa-EF-hand calcium binding protein secretagogin. The first variant (secretagogin-R22) is characterized by one single amino acid exchange (Q/R) at codon 22, most likely due to RNA editing. The second variant of secretagogin (setagin) consists of 49 amino acids. Due to a frame shift, only the first 27 amino acids are identical to secretagogin. We demonstrate that this protein truncation results in complete loss of the calcium binding capacity. Setagin expression was found in considerable amounts in the pancreas whereas secretagogin and secretagogin-R22 were also found in the central nervous system and organs containing neurendocrine cells.

A specific buffered antigen has been obtained, employing a method developed by the authors, stained with Bengal rose and intended for performing a fast agglutination reaction to confirm brucellosis. The antigen produces a clear and demonstrative agglutination reaction with positive sera. Practically, the test is readily carried out, and can be made a routine both in every serologic laboratory and for investigations under field conditions. The reaction produced with this antigen can determine dependably the epizootic status on a farm or in the herd. The diagnostic value of the antigen is essential, especially with swine. Besides, it shows a wide a diagnostic scope for brucellosis with all species of animals (97--98 per cent).

A Brucella buffered antigen, stained with Bengal rose by a method of the authors, was obtained. It showed a high distinguishing capacity with regard to the nonspecific agglutinations after Huddleson and Wright at a negative complement-fixation test for brucellosis with sera from cattle, pigs, sheep, and horses. Such differentiation, however, proved to be incomplete and for sera of different animals varied within the range of 34 to 0.0 per cent.