Multicolonization of human nasopharynx due to Neisseria spp.

The colonization due to Neisseria spp. in the nasopharynx of forty healthy adults was studied by using a selective medium that allows the differentiation of Neisseria species and inhibits the rest of pharyngeal microbiota. The medium detected a variety of colonial morphology types and some metabolic characteristics of the isolates. We demonstrated the multicolonization by several Neisseria spp. in the same individual, and we isolated several strains of the same species, after analysis by pulsed-field gel electrophoresis (PFGE) patterns obtained from the different colonial types previously identified as the same species. The forty adults studied were colonized by 112 forms of Neisseria spp., and twelve colonization patterns were obtained: one species (45%), two (45%), three (7.5%) and four (2.5%). N. perflava-N. sicca, either alone or in combination with other species was the most frequent isolate (92.5%). The analysis of PFGE patterns obtained from different colonial types revealed the multicolonization by several strains of the same species in some individuals. This fact was found in N. perflava-N. sicca (50%) and N. mucosa (2.5%)

Dynamics of a Sporadic Nosocomial Acinetobacter calcoaceticus – Acinetobacter baumannii Complex Population

Our objective was to improve current knowledge of sporadic (Spo) nosocomial Acinetobactercalcoaceticus-Acinetobacter baumannii (Acb) complex populations, and thus better understand the epidemiology of Spo and endemoepidemic (EE) strains. Between 1999 and 2010, 133 isolates of Spo Acb complex were obtained from a single hospital. Species were identified by gyrB-PCR, and via gyrB- and rpoB-sequencing. Clonal analysis was undertaken using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Susceptibility to antimicrobial agents was determined by microdilution and E-tests. Carbapenemase genes were detected by PCR. One hundred and one PFGE types were detected. A. baumannii was the most common (67/101 PFGE types), followed by Acinetobacter pittii (22/101), Acinetobacter lactucae (6/101), and Acinetobacter calcoaceticus (2/101). gyrB, rpoB1, and rpoB2 sequencing returned 49, 13, and 16 novel sequences, respectively. Sixty-three sequence types (STs) (38 new STs and 66 new alleles) were detected; the most common were ST2 (29/133 isolates) and ST132 (14/133). Twenty-six OXA-51 allelic variants were detected, nine of which were novel. The PFGE types were generally susceptible (88/101) to all the tested antimicrobials; 3/101 were carbapenem-resistant due to the presence of the genetic structure ISAba2-blaOXA-58-like-ISAba3, and 2/101 were multidrug-resistant. It can be concluded that the examined Spo Acb complex population was mainly composed of A. baumannii. Many different clones were detected (with ST2 clearly dominant), all largely susceptible to antimicrobials; multidrug resistance was rare. In contrast, a previously examined EE Acb population was composed of just four expanding, multidrug-resistant A. baumannii clones -ST2, ST3, ST15, and ST80-

Gold behavior in supergene profiles under changing redox conditions : the example of the Las Cruces Deposit, Iberian Pyrite Belt

The Las Cruces deposit is in the eastern end of the Iberian Pyrite Belt (SW Spain). It is currently being mined by Cobre Las Cruces S.A. The main operation is focused on the supergene Cu-enriched zone (initial reserves of 17.6 Mt @ 6.2% Cu). An Au-Ag-Pb–rich gossan resource (3.6 Mt @ 3.3% Pb, 2.5 g/t Au, and 56.3 g/t Ag) occurs in the upper part of the deposit. The Au grade ranges from 0.01 ppm to >100 ppm, and occurs as three different Au ore types: (1) Au mineralization in the upper part of the gossan linked to Fe-oxides lithofacies, (2) Au concentration in the lower part of the gossan associated with leached black shales, and (3) Au ore in the cementation zone related to subvertical fractures. A hydroseparation device has been used to obtain heavy mineral concentrates from selected samples of different ore types. Reflected-light microscopy, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and electron probe microanalysis (EPMA) were used to study the separated Au particles. Significant differences between the defined ore types include the Au-bearing lithologies, mineral associations, textural features, particle sizes, morphologies, and fineness. Au-rich minerals include native Au, Au-Ag electrum, and Au-Ag-Hg amalgams. Gold-bearing mineral associations include Pb-oxihalides, Fe-oxides, galena, pyrite, cinnabar, and Ag-sulfosalts. The Au enrichment mechanism in the supergene profile involves (1) dissolution of Au from the primary sulfides as chloride-rich ionic complexes during the weathering of the deposit under subaerial exposure; dissolved Au is transported downward through the supergene profile under acidic and oxidized conditions; (2) destabilization of the Au complexes by Fe-controlled redox reactions; as a consequence, coarse-grained, high-fineness Au particles precipitated in association with Fe-oxyhydroxides. This resulted in secondary concentration in the upper gossan; and (3) after deposition of cover sediments took place a progressive change in the system conditions resulting in a later Au remobilization as hydroxidehalide, hydroxide, thiosulfate, and bisulfide complexes in the lowermost gossan and cementation zone. The main pathways for migration of enriched fluids to the cementation zone are secondary permeability zones linked to Alpine reactivated faults. Deposition of Au seems to be related to fluid interaction with reductant lithologies, including black shales and the primary sulfides.This research is a contribution to projects P-S Anoxia (CGL2011-30011) and Metodica (CGL2010-21956-C02-02), which are supported by the Spanish government. The authors thank Cobre Las Cruces S.A. for the field assistance and the ongoing collaboration. We are also grateful to Joel Brugger, Steve Hill, and Tim Baker for their constructive suggestions to improve the manuscript

Association Between Preexisting Versus Newly Identified Atrial Fibrillation and Outcomes of Patients With Acute Pulmonary Embolism

Background Atrial fibrillation (AF) may exist before or occur early in the course of pulmonary embolism (PE). We determined the PE outcomes based on the presence and timing of AF. Methods and Results Using the data from a multicenter PE registry, we identified 3 groups: (1) those with preexisting AF, (2) patients with new AF within 2 days from acute PE (incident AF), and (3) patients without AF. We assessed the 90-day and 1-year risk of mortality and stroke in patients with AF, compared with those without AF (reference group). Among 16 497 patients with PE, 792 had preexisting AF. These patients had increased odds of 90-day all-cause (odds ratio [OR], 2.81; 95% CI, 2.33-3.38) and PE-related mortality (OR, 2.38; 95% CI, 1.37-4.14) and increased 1-year hazard for ischemic stroke (hazard ratio, 5.48; 95% CI, 3.10-9.69) compared with those without AF. After multivariable adjustment, preexisting AF was associated with significantly increased odds of all-cause mortality (OR, 1.91; 95% CI, 1.57-2.32) but not PE-related mortality (OR, 1.50; 95% CI, 0.85-2.66). Among 16 497 patients with PE, 445 developed new incident AF within 2 days of acute PE. Incident AF was associated with increased odds of 90-day all-cause (OR, 2.28; 95% CI, 1.75-2.97) and PE-related (OR, 3.64; 95% CI, 2.01-6.59) mortality but not stroke. Findings were similar in multivariable analyses. Conclusions In patients with acute symptomatic PE, both preexisting AF and incident AF predict adverse clinical outcomes. The type of adverse outcomes may differ depending on the timing of AF onset.info:eu-repo/semantics/publishedVersio

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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