The rat brain hippocampus proteome

The hippocampus is crucial in memory storage and retrieval and plays an important role in stress response. In humans, the CA1 area of hippocampus is one of the first brain areas to display pathology in Alzheimer's disease. A comprehensive analysis of the hippocampus proteome has not been accomplished yet. We applied proteomics technologies to construct a two-dimensional database for rat brain hippocampus proteins. Hippocampus samples from eight months old animals were analyzed by two-dimensional electrophoresis and the proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The database comprises 148 different gene products, which are in the majority enzymes, structural proteins and heat shock proteins. It also includes 39 neuron specific gene products. The database may be useful in animal model studies of neurological disorders.     

Determinants of breeding dispersal in the sand lizard, Lacerta agilis, (Reptilia, Squamata)

We studied determinants of breeding dispersal (the distance that an animal shifts its mean home range co-ordinate between reproductive events) in an individually marked population of sand lizards (Lacerta agilis) in south west Sweden during 1987–1991. Female breeding dispersal was not determined by age, size, body condition, or number of partners, and females and males that dispersed further did not experience a higher mortality. However, females with a low reproductive output dispersed further than females that reproduced more successfully, and males that lost in bodily condition dispersed further than males that better maintained body condition. We also looked for relationships between age-differences and band-sharing similarity (DNA fingerprinting = DFP) in three categories of lizards — all females, all males, and males and females — to establish whether males would be likely to mate with close kin. Age-difference was strongly correlated with band-sharing in only one category, males and females. When males were older than females this relationship was not significant. However, when females were older than males, age-difference was strongly correlated with band-sharing. Furthermore, females that were old enough to be the mothers of the courting males shared significantly more bands with these males than did the younger females, including the females of the same age as the males. Although parental-specific DFP bands necessary for establishing paternity among our adult lizards were inaccessible to us, we suggest that our circumstantial evidence strongly suggests that some males mate with their mothers. Males that were more closely related with their neighbours also moved further when we controlled statistically for age and mating success. We suggest that by mating with many partners males not only increase their mating success, but also increase the probability of mating with females with ‘good genes’: mean heterozygosity of parents (as revealed by micro-satellites) were strongly correlated with offspring survival.     

Analysis of vitelline envelope synthesis and composition during early oocyte development in gilthead seabream (Sparus aurata)

The oocyte vitelline envelope (VE) of gilthead seabream is composed of four known zona pellucida (ZP) proteins, ZPBa, ZPBb, ZPC, and ZPX. We have previously shown that the gilthead seabream ZP proteins are differentially transcribed in liver and ovary, with the expression in liver being under estrogenic control. However, although mRNA was found in both liver and ovary, only low ZPBa protein levels were detected in liver and plasma. Using isoform-specific ZP antibodies we show that ZPBa and ZPX translation products are present in the cytosol of stage I and II oocytes. In addition, the zpBa and zpX mRNAs were detected in early developing oocytes. During oocyte growth (vitellogenesis), the VE increased in thickness (>10 microm), and we show that the four ZP isoforms are present in different regions of the VE. ZPX was detected closest to the oocyte plasma membrane while the intermediate region was composed of ZPBa, ZPBb, and ZPC. At the outer layer, only ZPC was detected. When oocytes reach the fully grown stage they resume meiosis and hydration. As the oocyte expands, thinning to 4 microm, the VE acquire a striped and compact appearance at the electron microscopy level. This study provides further evidence for the oocyte origin of some ZP proteins in the gilthead seabream and suggests that the ZP proteins are differentially distributed within the VE.     

Direct microscopy of bacillus endospore germination in soil microcosms

Antagonistic endospore-forming Bacillus spp. offer a large potential as seed inoculants for control of soil-borne pathogens. In the soil, however, inoculated Bacillus endospores may remain dormant without germination, and plant protection can therefore be inefficient and unpredictable. A method based on direct fluorescence microscopy in soil microcosms was used to determine whether low-cost organic additives incorporated into seed coating material could stimulate endospore germination. Complex organic additives supported a high level of endospore germination of the fungal antagonist Paenibacillus polymyxa CM5-5. Skim milk is a low-cost additive that may be incorporated into seed coating material for efficient induction of Bacillus endospore germination in soil.     

A relation between TGF-β and mast cell tryptase in experimental emphysema models

Chronic obstructive pulmonary disease (COPD) is a multicomponent disease characterized by emphysema and/or chronic bronchitis. The aim of this study was to investigate the effect of cigarette smoke exposure on mast cells and mast cell function in vitro and in vivo in order to get further insight in the role of mast cells in the pathogenesis of emphysema. Cigarette smoke conditioned medium (CSM) induced the expression of mast cell tryptase (MMCP-6) in primary cultured mast cells. This tryptase expression was caused by the CSM-stimulated production of TGF-β in culture and neutralization of TGF-β suppressed the CSM-induced expression of tryptase in mast cells. An increase in mast cell tryptase expression was also found in an experimental model for emphysema. Exposure of mice to cigarette smoke increased the number of mast cells in the airways and the expression of mast cell tryptase. In accordance with the in vitro findings, TGF-β in bronchoalveolar lavage fluid of smoke-exposed animals was significantly increased. Our study indicates that mast cells may be a source of TGF-β production after cigarette smoke exposure and that in turn TGF-β may change the tryptase expression in mast cells.     

Identification of nine sequence types of the 16S rRNA genes of <Emphasis Type="Italic">Campylobacter jejuni</Emphasis> subsp. <Emphasis Type="Italic">jejuni</Emphasis> isolated from broilers

Background  

Campylobacter is the most commonly reported bacterial cause of enteritis in humans in the EU Member States and other industrialized countries. One significant source of infection is broilers and consumption of undercooked broiler meat. Campylobacter jejuni is the Campylobacter sp. predominantly found in infected humans and colonized broilers. Sequence analysis of the 16S rRNA gene is very useful for identification of bacteria to genus and species level. The objectives in this study were to determine the degree of intraspecific variation in the 16S rRNA genes of C. jejuni and C. coli and to determine whether the 16S rRNA sequence types correlated with genotypes generated by PFGE analysis of Sma I restricted genomic DNA of the strains.