Bilan initial d’imagerie de l’adénocarcinome pancréatique : données de la littérature sur la place actuelle de la tomographie par émission de positons au 18F-fluorodéoxyglucose (TEP FDG)

In pancreatic adenocarcinoma, initial imaging is essential to better select patients for surgery. Recent literature analysis of F18-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET) in pancreatic adenocarcinoma is summarized in the present article. Performances of FDG PET in the fields of lymph node involvement, metastatic involvement and therapeutic efficacy assessment are described for its correct use in pancreatic adenocarcinoma.     

Technological properties of Oenococcus oeni strains isolated from typical southern Italian wines

Aims: To isolate indigenous Oenococcus oeni strains suitable as starters for malolactic fermentation (MLF), using a reliable polyphasic approach. Methods and Results: Oenococcus oeni strains were isolated from Nero di Troia wines undergoing spontaneous MLF. Samples were taken at the end of alcoholic fermentation and during MLF. Wine samples were diluted in a sterile physiological solution and plated on MRS and on modified FT80. Identification of O. oeni strains was performed by a polymerase chain reaction (PCR) experiment using strain‐specific primers. Strains were further grouped using a multiplex RAPD‐PCR analysis. Then, six strains were inoculated in two wine‐like media with two different ethanol concentrations (11 and 13% vol/vol) with a view to evaluate their capacity to grow and to perform MLF. In addition, a quantitative PCR (qRT‐PCR) approach was adapted to monitor the physiological state of the strains selected. Conclusion: A positive correlation between the malolactic activity performance and the ability to develop and tolerate stress conditions was observed for two selected O. oeni strains. Significance and Impact of the Study: The results reported are useful for the selection of indigenous MLF starter cultures with desired oenological traits from typical regional wines. It should be the base for the improvement in organoleptic quality of typical red wine.     

Molecular taxonomy and biodiversity of rock fungal communities in an urban environment (Vienna, Austria)

The diversity of fungal communities on three different historical monuments in the city of Vienna (Austria) was analyzed and compared to the fungal diversity of microfungi on rock in the original quarry located in a rural area (Zogelsdorf, Austria). The fungal strains isolated were characterized by morphology and the complete rock fungal community was identified based on molecular data, that is, by sequencing parts of the small ribosomal subunit (18S) and internal transcribed spacer region 1 (ITS1). The genera Coniothyrium, Epicoccum and Phoma were found to be dominant {on} monument and rock surfaces. Additionally, black yeasts such as Exophiala species and microcolonial fungi like Sarcinomyces and Coniosporium which hitherto were regarded as typical rock inhabitants in semi-arid environments are frequently found on all rock surfaces in Vienna. The biodiversity of the fungi in the urban environment was much higher than on the same rock type in a rural environment, this difference can be attributed to the elevated organic pollution in the city.     

Quantification of illegitimate V(D)J recombinase-mediated mutations in lymphocytes of newborns and adults

We used a direct polymerase chain reaction (PCR) method for quantification of HPRT exons 2+3 deletions and t(14;18) translocations as a measure of illegitimate V(D)J recombination. We determined the baseline frequencies of these two mutations in mononuclear leukocyte DNA from the umbilical cord blood of newborns and from the peripheral blood of adults. In an initial group of 21 newborns, no t(14;18) translocations were detected (<0.049×10⁻⁷). The frequency of HPRT exons 2+3 deletions was 0.10×10⁻⁷ per mononuclear leukocyte, lower than expected based on the T-cell proportion of this cell fraction (55%–70%) and previous results using the T-cell cloning assay (2–3×10⁻⁷ per clonable T-cell). Phytohemagglutinin (PHA), as used in the T-cell cloning assay, was examined for its effect on the frequencies of these mutation events in mononuclear leukocytes from an additional 11 newborns and from 12 adults. There was no significant effect of PHA on t(14;18) translocations which were rare among the newborns (1 detected among 2.7×10⁸ leukocytes analyzed), and which occurred at frequencies from <1×10⁻⁷ (undetected) to 1.6×10⁻⁴ among the adults. The extremely high frequencies of t(14;18)-bearing cells in three adults were due mainly to in vivo expansion of two to six clones. However, PHA appeared to stimulate a modest (although not significant) increase in the frequency of HPRT exons 2+3 deletions in the leukocytes of the newborns, from 0.07×10⁻⁷ to 0.23×10⁻⁷. We show that both the direct PCR assay and the T-cell cloning assay detect similar frequencies of HPRT exons 2+3 deletions when calculations are normalized to blood volume, indicating that the apparent discrepancy is probably due to the different population of cells used in the assays. This direct PCR assay may have utility in characterizing the effects of environmental genotoxic agents on this clinically important recombination mechanism.     

Phylogenetic relationships of Eurasian pines (Pinus, Pinaceae) based on chloroplast rbcL, MATK, RPL20-RPS18 spacer, and TRNV intron sequences

The sequence divergence of chloroplast rbcL, matK, trnV intron, and rpl20-rps18 spacer regions was analyzed among 32 Pinus species and representatives of six other genera in Pinaceae. The total aligned sequence length is 3570 bp. Of the four sequences examined, matK evolved much faster than rbcL in Pinus and in other Pinaceae genera. The two noncoding regions did not show more divergence than the two coding regions, especially within each Pinus subgenus. Phylogenetic analyses based on these four sequences gave consistent results and strongly supported the monophyly hypothesis for the genus Pinus and its two recognized subgenera. Pinus krempfii, the two-flat-needle pine endemic to Vietnam, was placed in subgen. Strobus and showed closer affinity to subsect. Gerardianae. The ancient character of sect. Parrya is further confirmed. However, monophyly of the sect. Parrya is not supported by our data. Among the Eurasian pines of subgen. Pinus, Mediterranean pines formed one clade and the Asian members of subsect. Sylvestres formed another. The Himalayan P. roxburghii showed considerable divergence from all the other hard pines from both regions. Pinus merkusii was distinctly separated from all the Asian members of subsect. Sylvestres. The implications of our results for Pinus classification are discussed.     

Phylogenetic relationships ofPolemoniaceae inferred from 18S ribosomal DNA sequences

Cladistic analyses of chloroplast DNA disagree with current classifications by placingPolemoniaceae near sympetalous families with two staminal whorls, includingFouquieriaceae andDiapensiaceae, rather than near sympetalous families with a single staminal whorl, such asHydrophyllaceae andConvolvulaceae. To explore further the affinities ofPolemoniaceae, we sequenced 18S ribosomal DNA for eight genera ofPolemoniaceae and 31 families representing a broadly definedAsteridae. The distribution of variation in these sequences suggest some sites are hypervariable and multiple hits at these sites have obscured much of the hierarchical structure present in the data. Nevertheless, parsimony, least-squares minimum evolution, and maximum likelihood methods all support a monophyleticPolemoniaceae that is placed nearFouquieriaceae, Diapensiaceae and related ericalean families.     

Phenazine-1-carboxylic acid is negatively regulated and pyoluteorin positively regulated by gacA in Pseudomonas sp. M18

The biosynthesis of antimicrobial metabolites is controlled by the GacS/GacA two-component regulatory system in Pseudomonas species. The production of phenazine-1-carboxylic acid and pyoluteorin is differentially regulated by GacA in Pseudomonas sp. M18. Pyoluteorin was reduced to nondetectable level in culture of the gacA insertional mutant strain M18G grown in King's medium B broth, whereas phenazine-1-carboxylic acid production was increased 30-fold over that of the wild-type strain. Production of both antibiotics was restored to wild-type levels after complementation in trans with the wild-type gacA gene. Expression of the translational fusions phzA'-'lacZ and pltA'-'lacZ confirmed the effect of GacA on both biosynthetic operons.     

Expression of equine interleukin-18 by baculovirus expression system and its biologic activity

The equine interleukin-18 (IL-18) cDNA that contains the coding sequence was cloned and a recombinant baculovirus, named AcEIL-18, was constructed. The recombinant protein of the equine IL-18 was expressed by AcEIL-18 and its expression was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Insect cells infected with AcEIL-18 secreted a precursor IL-18 with 24 kilo dalton (kDa) into the culture supernatant. Western blot analysis showed that mature equine IL-18 about 18 kDa was also confirmed without co-expression of caspase-1. Culture supernatant from AcEIL-18 infected cells showed a synergistic effect with recombinant human interleukin-12 for induction of interferon-gamma gene expression in equine peripheral mononuclear cells, indicating that the recombinant equine IL-18 expressed in this study also has biological activity without any treatment.