Aims The EURO-ENDO registry aimed to study the management and outcomes of patients with infective endocarditis (IE). Methods and results Prospective cohort of 3116 adult patients (2470 from Europe, 646 from non-ESC countries), admitted to 156 hospitals in 40 countries between January 2016 and March 2018 with a diagnosis of IE based on ESC 2015 diagnostic criteria. Clinical, biological, microbiological, and imaging [echocardiography, computed tomography (CT) scan, 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)] data were collected. Infective endocarditis was native (NVE) in 1764 (56.6%) patients, prosthetic (PVIE) in 939 (30.1%), and device-related (CDRIE) in 308 (9.9%). Infective endocarditis was community-acquired in 2046 (65.66%) patients. Microorganisms involved were staphylococci in 1085 (44.1%) patients, oral streptococci in 304 (12.3%), enterococci in 390 (15.8%), and Streptococcus gallolyticus in 162 (6.6%). 18F-fluorodeoxyglucose positron emission tomography/computed tomography was performed in 518 (16.6%) patients and presented with cardiac uptake (major criterion) in 222 (42.9%) patients, with a better sensitivity in PVIE (66.8%) than in NVE (28.0%) and CDRIE (16.3%). Embolic events occurred in 20.6% of patients, and were significantly associated with tricuspid or pulmonary IE, presence of a vegetation and Staphylococcus aureus IE. According to ESC guidelines, cardiac surgery was indicated in 2160 (69.3%) patients, but finally performed in only 1596 (73.9%) of them. In-hospital death occurred in 532 (17.1%) patients and was more frequent in PVIE. Independent predictors of mortality were Charlson index, creatinine > 2 mg/dL, congestive heart failure, vegetation length > 10 mm, cerebral complications, abscess, and failure to undertake surgery when indicated. Conclusion Infective endocarditis is still a life-threatening disease with frequent lethal outcome despite profound changes in its clinical, microbiological, imaging, and therapeutic profiles.

Ammonium oxidation by autotrophic ammonia-oxidizing bacteria (AOB) is a key process in agricultural and natural ecosystems and has a large global impact. In the past, the ecology and physiology of AOB were not well understood because these organisms are notoriously difficult to culture. Recent applications of molecular techniques have advanced our knowledge of AOB, but the necessity of using PCR-based techniques has made quantitative measurements difficult. A quantitative real-time PCR assay targeting part of the ammoniamonooxygenase gene (amoA) was developed to estimate AOB population size in soil. This assay has a detection limit of 1.3 ؋ 10 5 cells/g of dry soil. The effect of the ammonium concentration on AOB population density was measured in soil microcosms by applying 0, 1.5, or 7.5 mM ammonium sulfate. AOB population size and ammonium and nitrate concentrations were monitored for 28 days after (NH 4 ) 2 SO 4 application. AOB populations in amended treatments increased from an initial density of approximately 4 ؋ 10 6 cells/g of dry soil to peak values (day 7) of 35 ؋ 10 6 and 66 ؋ 10 6 cells/g of dry soil in the 1.5 and 7.5 mM treatments, respectively. The population size of total bacteria (quantified by real-time PCR with a universal bacterial probe) remained between 0.7 ؋ 10 9 and 2.2 ؋ 10 9 cells/g of soil, regardless of the ammonia concentration. A fertilization experiment was conducted in a tomato field plot to test whether the changes in AOB density observed in microcosms could also be detected in the field. AOB population size increased from 8.9 ؋ 10 6 to 38.0 ؋ 10 6 cells/g of soil by day 39. Generation times were 28 and 52 h in the 1.5 and 7.5 mM treatments, respectively, in the microcosm experiment and 373 h in the ammonium treatment in the field study. Estimated oxidation rates per cell ranged initially from 0.5 to 25.0 fmol of NH 4 ؉ h ؊1 cell ؊1 and decreased with time in both microcosms and the field. Growth yields were 5.6 ؋ 10 6 , 17.5 ؋ 10 6 , and 1.7 ؋ 10 6 cells/mol of NH 4 ؉ in the 1.5 and 7.5 mM microcosm treatments and the field study, respectively. In a second field experiment, AOB population size was significantly greater in annually fertilized versus unfertilized soil, even though the last ammonium application occurred 8 months prior to measurement, suggesting a long-term effect of ammonium fertilization on AOB population size.Ammonium oxidation by autotrophic ammonia-oxidizing bacteria (AOB) is a key process in agricultural and natural ecosystems, with a large global impact. The product of this process, nitrite, is immediately oxidized by nitrite-oxidizing bacteria to nitrate, a nitrogen form susceptible to leaching. Nitrogen leaching can lead to groundwater pollution and surface and groundwater eutrophication. Nitrous oxide and nitric oxide, by-products of ammonia oxidation, contribute to the greenhouse effect and ozone layer depletion. On a local scale, loss of nitrate to groundwater and nitrous oxide and nitric oxide to the atmosphere reduces the amount of nitrogen available ...

CuO nanoparticles (CuO-NP) were synthesized in a hydrogen diffusion flame. Particle size and morphology were characterized using scanning mobility particle sizing, Brunauer–Emmett–Teller analysis, dynamic light scattering, and transmission electron microscopy. The solubility of CuO-NP varied with both pH and presence of other ions. CuO-NP and comparable doses of soluble Cu were applied to duckweeds, Landoltia punctata. Growth was inhibited 50% by either 0.6 mg L−1 soluble copper or by 1.0 mg L−1 CuO-NP that released only 0.16 mg L−1 soluble Cu into growth medium. A significant decrease of chlorophyll was observed in plants stressed by 1.0 mg L−1 CuO-NP, but not in the comparable 0.2 mg L−1 soluble Cu treatment. The Cu content of fronds exposed to CuO-NP is four times higher than in fronds exposed to an equivalent dose of soluble copper, and this is enough to explain the inhibitory effects on growth and chlorophyll content.

A Gram-negative, rod-shaped, motile, non-pigmented, facultative aerobe that grew optimally at pH 6?5 and 30 6C (strain PM1 T ) was isolated for its ability to completely degrade the gasoline additive methyl tert-butyl ether. Analysis of the 16S rRNA gene sequence indicated that this bacterium was a member of the class Betaproteobacteria in the Sphaerotilus-Leptothrix group. The 16S rRNA gene sequence identity to other genera in this group, Leptothrix, Aquabacterium, Roseateles, Sphaerotilus, Ideonella and Rubrivivax, ranged from 93 to 96 %. The chemotaxonomic data including Q-8 as the major quinone, C16 : 1v7c and C16 : 0 as the major fatty acids and a DNA G+C content of 69 mol%, support the inclusion of strain PM1 T in the classBetaproteobacteria. It differed from other members of the Sphaerotilus-Leptothrix group by being a facultative methylotroph that used methanol as a sole carbon source, and by also being able to grow heterotrophically in defined media containing ethanol, toluene, benzene, ethylbenzene and dihydroxybenzoates as sole carbon sources. On the basis of the morphological, physiological, biochemical and genetic information, a new genus and species, Methylibium petroleiphilum gen. nov., sp. nov., is proposed, with PM1 T (=ATCC BAA-1232 T =LMG 22953 T ) as the type strain.Organisms that can use one-carbon compounds as energy sources are called methylotrophs (Lidstrom, 2001). A subset of this group, the methanotrophs, can use methane as their sole carbon source. Methylotrophs have been extensively studied because of their potential use in biotechnology and bioremediation (Lidstrom & Stirling, 1990;Hanson & Hanson, 1996). The aerobic methylotrophs have representatives in the Proteobacteria, high-G+C and low-G+C Gram-positive bacteria that have been isolated from diverse environments. Within the Proteobacteria, the majority of the methylotrophs that have been isolated belong to either the Alphaproteobacteria or Gammaproteobacteria. Three genera, Methylobacillus (Urakami & Komagata, 1986), Methylophilus (Jenkins et al., 1987) and Methylovorus (Govorukhina & Trotsenko, 1991), in the class Betaproteobacteria are considered to be restricted facultative methylotrophs because they can use methanol but not methane as a sole carbon source, and can use only a limited number of other carbon sources such as glucose and fructose. Phylogenetic analysis based on their 16S rRNA gene sequence resulted in all of them being grouped in the order Methylophilales (Bratina et al., 1992;Garrity & Holt, 2001). Currently, none of the described methanotrophs belong to the class Betaproteobacteria. However, comparison of the 16S rRNA gene sequence indicated that isolate PM1T was most closely related to the class Betaproteobacteria in the SphaerotilusLeptothrix group (Bruns et al., 2001). In this study, morphological, physiological, biochemical and genetic information is used to propose a new genus and species, Methylibium petroleiphilum gen. nov., sp. nov. Strain PM1T was isolated from a mixed bacterial culture enriched with m...

Intestinal sulfate-reducing bacteria (SRB) growth and resultant hydrogen sulfide production may damage the gastrointestinal epithelium and thereby contribute to chronic intestinal disorders. However, the ecology and phylogenetic diversity of intestinal dissimilatory SRB populations are poorly understood, and endogenous or exogenous sources of available sulfate are not well defined. The succession of intestinal SRB was therefore compared in inbred C57BL/6J mice using a PCR-based metabolic molecular ecology (MME) approach that targets a conserved region of subunit A of the adenosine-5-phosphosulfate (APS) reductase gene. The APS reductase-based MME strategy revealed intestinal SRB in the stomach and small intestine of 1-, 4-, and 7-day-old mice and throughout the gastrointestinal tract of 14-, 21-, 30-, 60-, and 90-day-old mice. Phylogenetic analysis of APS reductase amplicons obtained from the stomach, middle small intestine, and cecum of neonatal mice revealed that Desulfotomaculum spp. may be a predominant SRB group in the neonatal mouse intestine. The toxic gas hydrogen sulfide (H 2 S) is generated from sulfate during anaerobic respiration by sulfate-reducing Archaea and Bacteria (21, 58). A possible link between H 2 S and chronic intestinal disorders has been evoked by data indicating increased numbers of intestinal sulfate-reducing bacteria (SRB) and rates of sulfidogenesis in inflammatory bowel disease (IBD) patients compared to healthy humans (12, 37). Hydrogen sulfide selectively impairs the oxidation of n-butyrate by colonic epithelial cells (42). Because membrane lipid biosynthesis, ion absorption, mucin synthesis, and detoxification processes in colonocytes depend on the oxidation of n-butyrate, diminished n-butyrate metabolism is likely to compromise the epithelial cell barrier (42). Sulfide-induced damage of the epithelial barrier function would promote translocation of bacterial and food antigens, resulting in local inflammatory responses to normally benign antigens, an outcome consistent with histopathological features of IBD (16, 61). Chronic exposure to H 2 S might also perturb normal cycles of epithelial renewal in the intestine, thereby predisposing to proliferative disorders such as colon cancer.Intestinal sulfate can be derived either from exogenous sources, namely sulfate in drinking water and dietary foodstuffs, or from endogenous sources such as sulfated mucins (sulfomucins), sulfate-conjugated bile, and chondroitin sulfate. Use of chemically bound, endogenous sulfate by SRB is facilitated through interactions with sulfatase-harboring bacteria (e.g., Bacteroides spp. [56]). Most goblet cells, a differentiated epithelial cell subtype that produces mucins, generate sulfomucins (22). The degree of sulfation, however, increases from proximal to distal segments of the intestine and is highest in those segments harboring dense bacterial populations, such as the cecum and colon (9,20).The ecology and taxonomy of intestinal SRB and their metabolic activities remain uncharacterized. Most studies of...

To reduce the cost of algal biomass production, mathematical model was developed for the first time to describe microalgae growth, lipid production and glycerin consumption under photoheterotrophic conditions based on logistic, Luedeking–Piret and Luedeking–Piret-like equations. All experiments were conducted in a 2 L batch reactor without considering CO2 effect on algae’s growth and lipid production. Biomass and lipid production increased with glycerin as carbon source and were well described by the logistic and Luedeking–Piret equations respectively. Model predictions were in satisfactory agreement with measured data and the mode of lipid production was growth-associated. Sensitivity analysis was applied to examine the effects of certain important parameters on model performance. Results showed that S0, the initial concentration of glycerin, was the most significant factor for algae growth and lipid production. This model is applicable for prediction of other single cell algal species but model testing is recommended before scaling up the fermentation of process.

Methylibium petroleiphilum PM1 is a methylotroph distinguished by its ability to completely metabolize the fuel oxygenate methyl tert-butyl ether (MTBE). Strain PM1 also degrades aromatic (benzene, toluene, and xylene) and straight-chain (C 5 to C 12 ) hydrocarbons present in petroleum products. Whole-genome analysis of PM1 revealed an ϳ4-Mb circular chromosome and an ϳ600-kb megaplasmid, containing 3,831 and 646 genes, respectively. Aromatic hydrocarbon and alkane degradation, metal resistance, and methylotrophy are encoded on the chromosome. The megaplasmid contains an unusual t-RNA island, numerous insertion sequences, and large repeated elements, including a 40-kb region also present on the chromosome and a 29-kb tandem repeat encoding phosphonate transport and cobalamin biosynthesis. The megaplasmid also codes for alkane degradation and was shown to play an essential role in MTBE degradation through plasmid-curing experiments. Discrepancies between the insertion sequence element distribution patterns, the distributions of best BLASTP hits among major phylogenetic groups, and the G؉C contents of the chromosome (69.2%) and plasmid (66%), together with comparative genome hybridization experiments, suggest that the plasmid was recently acquired and apparently carries the genetic information responsible for PM1's ability to degrade MTBE. Comparative genomic hybridization analysis with two PM1-like MTBE-degrading environmental isolates (ϳ99% identical 16S rRNA gene sequences) showed that the plasmid was highly conserved (ca. 99% identical), whereas the chromosomes were too diverse to conduct resequencing analysis. PM1's genome sequence provides a foundation for investigating MTBE biodegradation and exploring the genetic regulation of multiple biodegradation pathways in M. petroleiphilum and other MTBE-degrading beta-proteobacteria.Methylibium petroleiphilum strain PM1, which belongs to a newly described genus and species (57), is a motile bacterium belonging to the Comamonadaceae family of the Betaproteobacteria and is an important member of subsurface microbial communities in many gasoline-contaminated aquifers. Furthermore, PM1 is a methylotroph that can grow aerobically on the fuel oxygenate methyl tert-butyl ether (MTBE) and oxidize it completely to carbon dioxide (9, 34). MTBE is a suspected carcinogen that has contaminated drinking water wells throughout the United States due to the preponderance of underground leaking storage tanks, the widespread usage of MTBE, and its recalcitrance and mobility in groundwater. PM1 can also oxidize aromatic hydrocarbons (toluene, benzene, oxylene, and phenol) (20) and n-alkanes (C 5 to C 12 ) (57; K. Hristova, unpublished data) and has been used in two bioaugmentation field trials in gasoline-contaminated aquifers in California (67) and Montana (18,73). In contaminated sites amended with oxygen, in situ MTBE degradation was observed and corresponded to increases in native populations of Methylibium sp. (ϳ99% similarity to PM1, based on the 16S rRNA gene) (38,67,82). PM1-l...

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