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The expression of Pseudomonas fluorescens F113 genes in the presence and absence of the phytopathogenic fungus Pythium ultimum was monitored to determine the ability of the fungus to alter genetic expression in Pseudomonas. Results indicate a repression of several gene clusters in P. fluorescens F113 resulting in a reduction of ecological fitness in this strain of bacteria.

Peripheral arterial disease (PAD), is a common manifestation of systemic atherosclerosis. Advances on the development of such vascular disease have described with a number of novel risk factors. Hyperviscosity, due to alterations of blood cells and plasma components, may play a role on the pathogenesis of the disease. Aim of this study was to evaluate the possible association between hemorheological variables and PAD. The hemorheological variables [whole blood viscosity (WBV), erythrocyte deformability index (DI), plasma viscosity (PLV)] were analyzed in 90 patients and in 180 healthy subjects. WBV and PLV were measured by a Rotational Viscosimeter and DI by a filtrometer. DI and PLV were significantly different in patients as compared to controls. To investigate the possible association between these parameters and the disease we divided the study population into tertiles. At the univariate analysis, we found a significant association between the highest tertiles of PLV, of DI and the disease. A model adjusted for traditional risk factors showed an association between highest tertiles of PLV and PAD. After adjustment for confounding parameters highest tertiles of PLV remained to be significantly associated with the disease. Our data indicate that an alteration of plasma viscosity may modulate the predisposition to PAD. [ABSTRACT FROM AUTHOR]

Rhodococcus sp. strain BCP1, known for its capacity to grow on short-chain n-alkanes (C2 to C7) and to cometabolize chlorinated solvents, was found to also utilize medium- and long-chain ,i-alkanes (C12 to C24) as energy and carbon sources. To examine this feature in detail, a chromosomal region which includes the alkB gene cluster encoding a non-heme di-iron monooxygenase (alkB), two rubredoxins, and one rubredoxin reductase was cloned from the BCP1 genome. Furthermore, the activity of the aIkB gene promoter (P alkB) was examined in the presence of gaseous, liquid, and solid n-alkanes along with intermediates of the putative n-alkane degradation pathway. A recombinant plasmid, pTP alkB LacZ, was constructed by inserting the lacZ gene downstream of P a1kB' and it was used to transform Rhodococcus sp. strain BCP1. Measurements of β-galactosidase activity showed that aIkB is induced by C6 to C22 n-alkanes. Conversely, C2 to C5 and >C22 n-alkanes and alkenes, such as hexene, were not inducers of alkB expression. The effects on P alkB expression induced by alternative carbon sources along with putative products of n-hexane metabolism were also evaluated. This report highlights the great versatility of Rhodococcus sp. strain BCP1 and defines for the first time the aIkB gene transcriptional start site and the aIkB promoter-inducing capacities for substrates different from n-alkanes in a Rhodococcus strain. [ABSTRACT FROM AUTHOR]

A histidine-kinase cheA gene in Pseudomonas pseudoalcaligenes KF707 plays a central role in the regulation of metabolic responses as well as in chemotaxis. Non-chemotactic mutants harboring insertions into the cheA gene were screened for their ability to form biofilms in the Calgary biofilm device. Notably, ≥95% decrease in the number of cells attached to the polystyrene surface was observed in cheA mutants compared to the KF707 wild-type biofilm phenotype. The ability to form mature biofilms was restored to wild-type levels, providing functional copies of the KF707 cheA gene to the mutants. In addition, phenotype micro-arrays and proteomic analyses revealed that several basic metabolic activities and a few periplasmic binding proteins of cheA mutant cells differed compared to those of wild-type cells. These results are interpreted as evidence of a strong integration between chemotactic and metabolic pathways in the process of biofilm development by P. pseudoalcaligenes KF707. [ABSTRACT FROM AUTHOR]

BACKGROUND: The mechanism by which high circulating homocysteine concentrations are a risk factor for atherothrombosis is incompletely understood. A proinflammatory state is related to atherosclerosis, and recent studies suggest that acute phase reactants correlate with circulating concentrations of homocysteine. OBJECTIVE: We determined whether high concentrations of inflammatory markers are associated with hyperhomocysteinemia independently of dietary vitamin intakes, vitamin concentrations, and cardiovascular disease risk factors in a large, representative sample of the general population. DESIGN: Five hundred eighty-six men and 734 women were randomly selected from the inhabitants of 2 small towns near Florence, Italy. RESULTS: After adjustment for multiple potential confounders, interleukin 1 receptor antagonist (IL-1ra) and interleukin 6 (IL-6) concentrations were significantly (P < 0.001) associated with plasma homocysteine concentrations in older (>65 y) populations. Compared with participants in the lowest IL-6 tertile, those in the highest tertile had a higher risk of having homocysteine concentrations that were high (>30 micromol/L; odds ratio: 2.6; 95% CI: 1.1, 5.6; P = 0.024) or in the intermediate range 15-30 micromol/L (odds ratio: 1.6; 95% CI: 1.2, 2.2; P = 0.0014). Sedentary state, intakes of vitamin B-6 and folic acid, and serum folate, vitamin B-12, vitamin B-6, and alpha-tocopherol concentrations were significant independent correlates of homocysteine. CONCLUSIONS: High circulating concentrations of IL-1ra and IL-6 are independent correlates of hyperhomocysteinemia and may explain, at least in part, the association between homocysteine and atherosclerosis. Copyright © 2005 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To evaluate dietary habits and lifestyle of Italian subjects, to provide current data on adequacy of the nutritional guidelines and recommendations especially in relation to primary prevention of cardiovascular diseases and to assess the influence of dietary habits on lipid profile and homocysteine levels. DESIGN:: Cross-sectional. SETTING:: Population-based study. SUBJECTS:: A sample of 520 clinically healthy subjects (211 males, 309 females) with a mean age of 46?y, living in Florence area, Italy. INTERVENTIONS:: Dietary pattern was assessed by trained dietitians through a semiquantitative food questionnaire. Fasting blood samples were drawn for assessment of lipid profile, homocysteine and circulating vitamins. RESULTS:: Contribution from total fats was over 30%in about 70%of subjects and intake of saturated fatty acids (SFA) was above the recommended values in at least 40%of the study population. Furthermore, almost the whole (99.6%) population reported low intake of polyunsaturated fatty acids (PUFA). High levels of total cholesterol were present in over 40%of the study population, whereas abnormal values of LDL-cholesterol were observed in about 30%. High levels of homocysteine were found in 11.7%of the study population. An extremely high percentage of subjects reported low intake of vitamins, especially with regard to folic acid (89%), vitamin B6 (70.1%) and vitamin E (99.6%). In a multiple linear regression model, circulating levels of vitamin B12 and folic acid, and intake of alcohol and vitamin C resulted in being independently associated with homocysteine plasma levels. CONCLUSIONS:: In a typical Mediterranean country, general outlines of Mediterranean diet are not completely followed, especially concerning total fats, SFA, PUFA and vitamins'intake. SPONSORSHIP:: Ministero della Salute (Italy)-‘Progetto per la Salute e la Prevenzione di Malattia’2001-2003.European Journal of Clinical Nutrition (2005) 59, 584-591. doi:10.1038/sj.ejcn.1602112 Published online 2 March 2005 [ABSTRACT FROM AUTHOR]

Alginate polymer was evaluated as a carrier for seed inoculation with a genetically modified strain Pseudomonas fluorescens F113LacZY, which protects sugar-beet against Pythium-mediated damping-off. F113LacZY survived in alginate beads at 5 log CFU/ bead or higher counts for 8 weeks of storage, regardless of the conditions of incubation. In plant inoculation experiments, colonisation of the growing area of the root by F113LacZY, derived from alginate beads placed in the soil next to the seed or from an alginate coating around the seeds, was improved compared with application of just free cells of the strain. F113LacZY trapped in alginate beads was an effective producer of antifungal phloroglucinols as indicated by direct HPLC quantification of phloroglucinols and in vitro inhibition of both the indicator bacterium Bacillus subtilis A1 and the pathogenic fungus Pythium ultimum. Alginate polymer represents a promising carrier for the delivery of biocontrol inoculants for root colonisation and production of antifungal metabolites. [ABSTRACT FROM AUTHOR]

Lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) are frequently detected in sera from patients affected by systemic lupus erythematosus (SLE). However, the role of antiphospholipid antibodies (aPL) in thrombus formation has not been defined as yet.Twenty-two patients affected by SLE, all fulfilling the 1982 ARA revised criteria, and twenty healthy subjects were investigated for the presence of LA, aCL and other aPLs. Monocyte procoagulant activity-PCA (Tissue Factor production) was evaluated by one stage plasma recalcification time. In all patients the plasma levels of F1 + 2 and of plasmin ogen activator inhibitor (PAI) were also determined. Monocyte PCA was significantly higher in SLE patients with LA and/or aCL in comparison to SLE patients without LA and/or aCL (p < 0.01) and to controls (p < 0.05). However, no connection was observed between PCA expression by mononuclear cells and LA or aCL levels. No differences in F1 + 2 and PAI plasma levels were found between SLE patients with or without aPL and controls. In our SLE patients LA and/or aCL positivity appears strictly related to an increased monocyte activation that could play an important role in the occurrence of thrombotic events. [ABSTRACT FROM PUBLISHER]