[Protease-resistant prion protein (PrPres) in the blood of offspring of cows that developed BSE]. / Untersuchung von BSE-Nachkommen auf Proteaseresistentes Prion Protein (PrPres) im Blut.

The goal of the present study was to investigate whether protease-resistant prion protein (PrPres) occurs in plasma samples of offspring of cows that developed bovine spongiform encephalopathy (BSE; group A) and to compare the prevalence with that of a healthy control group in 2006 (Group B). Group A consisted of 181 offspring of cows that developed BSE and group B consisted of 240 healthy animals from a region in Switzerland where no cases of BSE occurred from 2001 to the end of 2006. All plasma samples were evaluated using Alicon PrioTrap, an antemortem test for PrPres. The time between birth of the offspring and onset of BSE in the dam was calculated to determine its relationship with the presence of PrPres in the plasma of the offspring. From 181 offspring, 29 (16.1%) had PrPres-positive plasma samples. Offspring that were born within one year of the onset of BSE in the dam had a significantly higher prevalence of PrPres-positive plasma samples than those born more than one year before the onset of BSE in the dam. Ten (4.2%) of 240 control cattle had PrPres-positive plasma samples. Thus, PrPres can be detected in bovine blood and occurs more frequently in the offspring of cows that develop BSE than in cattle of a healthy control population.

Discovery of new DNA amplification loci in prostate cancer by comparative genomic hybridization.

BACKGROUND: DNA sequence amplifications are involved in the progression of many tumor types, and have also been found in advanced prostate cancer. The aim of this study was to detect new loci of DNA amplifications in prostate cancer. METHODS: Comparative genomic hybridization (CGH) was used for whole genome screening of DNA sequence copy number alterations in 27 advanced prostate cancers. RESULTS: The most prevalent changes were losses of 8p, 13q (52%, each), 6q (48%), 18q (37%), 5q (30%), 2q, 4q and 16q (26%, each), and gains of 8q (48%), Xq (40%), and Xp (26%). In addition, 16 high-level amplifications were found. These included Xq12 (five), 8q24 (two), and 11q13 (one) with known putative target genes (androgen receptor, MYC and Cyclin D1), and 1q21-25 (three), 10q22 (two), 17q23-24 (two), and 8q21 (one) where the target genes remain unknown. CONCLUSIONS: High-level amplifications at different chromosomal sites occur in advanced prostate cancer. The detection of amplified chromosomal regions may serve as a starting point to discover novel oncogenes involved in prostate cancer progression.

Expression profile and subcellular location of the plasmid-encoded virulence (Spv) proteins in wild-type Salmonella dublin.

The plasmid-encoded virulence genes (spvABCD) in nontyphoid Salmonella strains mediate lethal infections in a variety of animals. Previous studies have shown that these genes are transcriptionally regulated by stationary-phase growth. We studied the expression profile and the subcellular locations of the SpvABCD proteins in wild-type S. dublin by using polyclonal antibodies against SpvA, SpvB, SpvC, and SpvD. The cellular levels of the individual proteins were determined during growth by quantitative immunoblotting. As expected, SpvA, SpvB, SpvC, and SpvD were not detectable before the late logarithmic growth phase and appeared in the sequence SpvA, SpvB, SpvC, and SpvD. In contrast to the transcriptional regulation, however, SpvA and SpvB reached their maximal expression shortly after induction and declined during further growth whereas SpvC and SpvD expression remained high throughout the stationary phase, indicating that the Spv proteins are individually regulated at a posttranscriptional level. To localize SpvABCD within the bacteria, the cells were fractionated into the periplasmic, cytoplasmic, inner membrane, and outer membrane components. The cell fractions and the culture supernatant were analyzed by immunoblotting. SpvA was present in the outer membrane, SpvB was present in the cytoplasm and the inner membrane, and SpvC was present in the cytoplasm. SpvD was secreted into the supernatant; however, a substantial portion of this protein was also detected in the cytoplasm and membranes. The molecular weights of SpvD in the supernatant and in the cytoplasm appeared to be equal, suggesting that SpvD is not cleaved upon secretion.

Plasmid virulence gene expression induced by short-chain fatty acids in Salmonella dublin: identification of rpoS-dependent and rpo-S-independent mechanisms.

The Salmonella plasmid virulence spvABCD genes are growth phase regulated and require RpoS for maximal expression in stationary phase. We identified a growth phase-independent expression of spv which is mediated by short-chain fatty acids. During this fatty acid-mediated expression of spv, RpoS is required for induction only during exponential phase. In stationary phase, an rpoS-independent mechanism is responsible for expression of spv.

Mutational analysis of SpvR binding to DNA in the regulation of the Salmonella plasmid virulence operon.

The Salmonella plasmid-borne spvR gene encodes a 33-kDa regulatory protein that activates transcription of the spvABCD operon during the stationary phase of bacterial growth. We used gel mobility shift assays to demonstrate that SpvR recognizes a specific target DNA sequence within a 318-bp EcoRI-ApaI fragment upstream of spvA. The addition of unlabeled target DNA to the radioactive labeled DNA-SpvR complex resulted in competitive inhibition of band retardation confirming the specificity of SpvR binding. Introduction of target DNA on a high copy number plasmid into wild-type Salmonella dublin Lane resulted in a substantial decrease of SpvB synthesis, confirming the binding properties of this DNA segment in vivo. Three SpvR mutants were constructed and were shown to abolish the positive regulatory function of SpvR. By site-specific mutagenesis of spvR, three single amino acids within the putative SpvR N-terminal alpha-helix domains were substituted by prolines. This resulted in loss of binding to the spvA promoter sequence and in loss of activation of the spvABCD genes. This study demonstrates that the regulatory function of SpvR is mediated by specific binding to the promoter region of the spvABCD operon.

Studies on some Egyptian foods. Part 1: Biochemical and biological evaluation.

General chemical analysis of some Egyptian legumes (lupinus termis and fenugreek seeds) and biological evaluation for their proteins were investigated. Results showed that lupinus termis and fenugreek seeds have high protein contents (with the exception of germinated fenugreek). They are good sources of calcium and phosphorus. Raw seeds gave low PER and NPR values. However, these values increase after roasting or germination.

Studies on some Egyptian foods. Part 2: The effect of protein on blood constituents of rats.

This study was undertaken to study the changes of the blood constituents of rats fed different proteins (lupinus termis, Guiza 1, 2 and balady; fenugreek seeds, raw, roasted, and germinated). The total serum protein for animals fed casein was slightly higher than those fed other proteins. Total serum protein of animals fed lupinus termis, roasted and germinated fenugreek was higher than those fed raw seeds. The albumin/globulin ratios showed a similar trend. The ratio of nonessential to essential free serum amino acids of rats fed non-protein diet was higher than those fed protein. Lupinus termis and fenugreek seeds are good sources of protein. Treatment of seeds either by heat of germination improves the nutritive value of the proteins.