Surface coil magnetic resonance imaging

Detection of MR signals with surface coils provides increased signal-to-noise ratio for superficial structures relative to detection by circumferential coils, permitting improved spatial resolution. Different geometries of surface coils can be used for different regions. Coils that are flat or curved to fit body contours are good for general imaging, with a range of coil sizes useful for structures of different size or depth. Solenoidal coils are useful for imaging protruding structures such as breasts, while smaller versions of conventional circumferential coils that can be slipped over limbs are useful for imaging extremities.     

Analysis of outer membrane proteins which are associated with growth of Bacteroides thetaiotaomicron on chondroitin sulfate.

By analyzing outer membrane proteins of Bacteroides thetaiotaomicron on two-dimensional polyacrylamide gels, we were able to identify 10 protein spots that were associated with growth on chondroitin sulfate but not with growth on glucuronic acid or other monosaccharides. These proteins were distinct from the outer membrane polypeptides that were associated with growth on two other negatively charged polysaccharides, polygalacturonic acid and heparin. Of the 10 protein spots that were associated with growth on chondroitin sulfate, 4 could be detected on immunoblots with antiserum that had been raised against outer membranes from bacteria grown on chondroitin sulfate and then cross-adsorbed with membranes from bacteria grown on glucose. Synthesis of these four proteins appeared to be regulated coordinately with synthesis of the two enzymes that degrade chondroitin sulfate, chondroitin lyase I and II. Although one of the four proteins (Mr 110,000) was similar in molecular weight to the chondroitin lyases, the cross-adsorbed antiserum which detected this outer membrane protein did not cross-react with either of these two enzymes.     

Vergleichende Mikromorphologie der Narbenoberflächen bei den Angiospermen; Zusammenhänge mit Pollenoberflächen bei heterostylen Sippen

Stigmatic surfaces of about 250 species from more than 100 families were examined by scanning electron microscopy. There are five main groups which differ by the amount of secretion, the morphology of the surface and the distribution of receptive cells. The types of stigmatic surfaces are often remarkably constant on the family level.Ericaceae andLiliaceae are examples for very heterogenous families. Particular interest was paid to heteromorphic (heterostylous and cleistogamous) species. In most heterostylous species there is a close morphological correlation between the stigmatic surface and the sculpture of compatible pollen. Heterostyly was established for the genusGoniolimon. The dimorphism of plants with chasmogamous and cleistogamous flowers is a phenomenon which is not comparable to the polymorphism of heterostylous forms.

     

Identification and genetic mapping of a herpes simplex virus capsid protein that binds DNA

Herpes simplex virus virion protein 19C (VP19C) is a constituent of both unenveloped (nuclear) and enveloped (cytoplasmic) capsids. In this paper we report that 32P-labeled DNA, either supercoiled or linear double stranded, efficiently bound to VP19C electrically transferred from denaturing polyacrylamide gels containing electrophoretically separated proteins from purified capsids. Analyses of the polypeptides specified by herpes simplex virus type 1 X herpes simplex type 2 recombinants with respect to electrophoretic mobility and binding of 32P-labeled DNA indicate that VP19C maps at the same location as infected cell polypeptide 32 and is derived from it.     

Dietary docosahexaenoic acid is retroconverted in man to eicosapentaenoic acid, which can be quickly transformed to prostaglandin I3

In a 24 h kinetic study docosahexaenoic acid (DCHA, C22:6n-3) or eicosapentaenoic acid (EPA, C20:5n-3) were given in a single dose to healthy male volunteers. PGI₃-M, the main urinary metabolite of prostaglandin I₃ was below the detection limit in the control periods, but was excreted already in the first 4 h after ingestion of DCHA or EPA and decreased thereafter. Excretion of PGI₂-M did not change significantly. In a second dietary trial DCHA and EPA were given cross-over to 7 healthy male volunteers for 6 days. PGI₃-M was formed after DCHA and EPA in amounts of 35 and 20 % of PGI₂-M and showed a considerable interindividual variation. The structure of PGI₃-M was verified by independant biochemical synthesis. Our data indicate that dietary DCHA is retroconverted to EPA in man, which is quickly transformed - like dietary EPA itself - to prostaglandin I₃. DCHA may therefore serve as a precursor fatty acid for EPA and its cyclooxygenated and lipoxygenated products.     

The Electrical Conductivity of Bovine Milk in Mastitis Diagnosis

The electrical conductivity (EC) of milk is mainly a function of the electrolyte concentration in the milk and therefore raised in mastitis. The present investigation was aimed at elaborating, if possible, a diagnostic model for screening purposes based on EC determinations and consistent with the diagnostic procedures and interpretations commonly used in laboratory milk diagnosis in the Nordic countries (Klastrup 1975). According to this diagnosis (here called reference diagnosis) cell numbers above 300,000/ml (cell count or the corresponding CMT-score) in foremilk quarter samples during the main part of the lactation period and significantly above the lowest value on within-udder comparison during late lactation are considered indicative of mastitis and bacteriological examinations are made when called for.     

The structural gene for the mitochondrial aldehyde dehydrogenase maps to human chromosome 12

Summary A cloned 850 bp cDNA fragment corresponding to the 3-coding part of human ALDHI-mRNA was used as a probe for the chromosomal assignment of the ALDHI gene. Southern blot analysis of human-rodent somatic cell hybrids indicates that the human ALDHI gene resides on chromosome 12.Dedicated to Prof. Dr. H. Holzer on the occasion of his 65. birthday     

Inhibition of microbial growth by interference with siderophore biosynthesis. Oxidation of primary amino groups in aerobactin synthesis by Escherichia coli

Abstract The first step of aerobactin biosynthesis, oxidation of an aliphatic primary amino group to an N -hydroxy-amino compound seems to be involved in the biosynthesis of most of the hydroxamatetype siderophores which are widely distributed among bacteria and fungi. Therefore, the first step of aerobactin biosynthesis, oxidation of lysine to N ⁶-hydroxylysine was studied as a model reaction using a strain of Escherichia coli that contains the first gene aerA of aerobactin synthesis on a multi-copy plasmid and which is lacking the gene for the subsequent step in the pathway. In addition, culture conditions are described which lead to the secretion of N ⁶-hydroxylysine into the medium in amounts that can easily be quantitatively determined by a simple, reliable chemical assay. This assay can be used for screening inhibitors of the oxidation of α-amino groups, which should interfere with the biosynthesis of siderophore hydroxamates and thus should create bacteriostatic conditions.     

Molecular characterization of the gene coding for major outer membrane protein OmpA from Enterobacter aerogenes

The ompA gene from Enterobacter aerogenes was subcloned into a low-copy-number plasmid vector and the resultant plasmid, pTU7En, used to study its expression in Escherichia coli K12. Although the gene was strongly expressed and large amounts of OmpA protein were present in the outer membrane its product was not functionally identical to the E. coli polypeptide. In particular, the E. aerogenes OmpA protein was unable to confer sensitivity to OmpA-specific phages of E. coli. When the primary structure of the protein was deduced from the nucleotide sequence of its gene it was found that three domains differed extensively from the corresponding regions of the E. coli protein. As two of these are known to be exposed on the cell surface we inferred that these alterations are responsible for differences in the biological activity of the two proteins.