Experimental Arthritis in the Rat Induced by the Superantigen Staphylococcal Enterotoxin A.

The pathogenesis of rheumatoid arthritis (RA) is incompletely understood. Human endogenous retroviruses (HERVs) and their superantigenic envelope protein (env) have been implicated in the pathogenesis of RA. In the present investigation, the arthritogenic potential of the superantigen staphylococcal enterotoxin A (SEA) has been investigated. In the present investigation, the bacterial superantigen staphylococcal enterotoxin A (SEA) was injected into the right knee joint of 15 Lewis rats. Further nine animals received saline. Animals were sacrificed one, five and 10 days after the injection, respectively. The antigens CD3, CD4, CD8, MHC class I, MHC class II, Pax5 and CD138 were investigated by immunohistochemistry on cryo-sections. After intra-articular SEA injection, the inflammation was initially dominated by CD8+ T cells. In the course of the investigation, the numbers of CD4+, Pax5+, CD138+ and MHC class II+ cells increased. CD3 was expressed in low numbers as compared to CD8. After saline injection, no similar inflammatory response has been detected. The arthritis induced by the superantigen SEA may be a novel model for inflammatory joint diseases, that is rheumatoid arthritis or juvenile idiopathic arthritis.

[A handicap for life - overweight and obesity in pre-school children in Karlsruhe]. / Ballast fürs Leben - Ubergewicht und Adipositas bei Karlsruher Vorschulkindern.

BACKGROUND: Within the past few years the number of children and adolescents in Germany presenting with overweight and obesity has continually increased. A final review of the present situation is not possible, since the investigations in different regions of Germany vary greatly. The body weight data in different age categories of schoolchildren are mostly collected as a part of the school enrollment medical checkup. GOAL: The present situation of overweight and obesity in preschool children in Karlsruhe is reported in two prevalence studies. METHOD: The data and facts on preschool children were collected within the enrollment medical checkup between the ages of three to seven years. RESULTS: Every 13 th child in Karlsruhe's kindergartens is overweight. Every 8 th child with the school enrollment medical checkup is overweight, and almost half of them are obese. The number of overweight children begins at about the age of five, it increases continuously and doubles within two years from 8 to 16 %. Every 5 (th) child of families of non-German origin is overweight. DISCUSSION: The number of overweight and obese children increases continually during preschool age. In the modern way of living, children with genetic predisposition hardly have a chance to keep their overweight in control through sports and healthy eating habits. Hence children of socioeconomically underprivileged families need more support and guidance to achieve a healthy life. The consequence of these alarming results prompted Karlsruhe in 2002 to carry out a project with intervention-programmes for kindergartens within the areas of physical exercise and eating habits.

Molecular characterization of co-transcribed genes from Streptomyces tendae Tü901 involved in the biosynthesis of the peptidyl moiety and assembly of the peptidyl nucleoside antibiotic nikkomycin.

Six genes (nikP1, nikP2, nikS, nikT, nikU, and nikV) from Streptomyces tendae Tu901 were identified by analysis of the nucleotide sequence of the nikkomycin gene cluster. These genes, together with the previously described nikQ and nikR, span 9.39 kb and are transcribed as a polycistronic mRNA in a growth-phase-dependent manner. The nikP1 gene encodes a non-ribosomal peptide synthase consisting of an adenylation domain, a thiolation domain, and an N-terminal 70-residue segment of unknown function. The amino acid sequence encoded by the nikP2 gene displays similarity to the sequences of thioesterases, and the nikS product belongs to a superfamily of proteins characterized by a specific ATP-binding fold. The N-terminal 70 amino acids of the predicted nikT gene product show significant sequence similarity to acyl carrier proteins, and the C-terminal 330 amino acids to aminotransferases. The sequences of the deduced proteins NikU and NikV exhibit similarity to components S and E, respectively, of glutamate mutase from Clostridium. Disruption of the nikP1, nikS, nikT, or nikV gene by insertion of a kanamycin resistance cassette abolished formation of nikkomycins I, J, X, and Z, all of which contain hydroxypyridylhomothreonine as the peptidyl moiety. The nikP1 mutants, and the nikS and nikT mutants accumulated the nucleoside moieties nikkomycin Cz, and nikkomycins Cx and Cz, respectively. The nikV mutants formed nikkomycins Ox and Oz, which contain 2-amino-4-hydroxy-4-(3'-hydroxy-6'-pyridyl) butanoic acid as the peptidyl moiety. The nikP2 mutants synthesized nikkomycins I, J, X, and Z, but amounts of nikkomycins I and X, which contain formylimidazolone as the base, were lower. Feeding formylimidazolone to nikP2 mutants restored the ability to form nikkomycins I and X. Our results indicate that nikU and nikV are required for the synthesis of hydroxypyridylhomothreonine, the genes nikP1, nikP2 and nikS are required for the assembly of nikkomycins, and nikT is required for both pathways. The putative activities of each of their products are discussed.