BackgroundTreatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis.Methodology/Principal FindingsThis was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO®) were obtained. 45 of 311 blood cultures (14.5%) and 94 of 311 PCRs (30.1%) were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5) hours for the PCR and 68 (52.2, 88.5) hours for BC (p<0.01). PCR median time to result was dependent on technician availability (53.5 hours on Saturdays, 7.2 hours under optimal logistic conditions). PCR results showed good correlation with procalcitonin (p<0.001). In 34% of patients with positive PCRs antimicrobial therapy was considered inadequate according to assessment of clinical arbitrators including 5 patients with vancomycin-resistant enterococci (VRE), 3 cases with multiresistant staphylococci, and 4 patients with fungi.ConclusionsThe results of this observational study support the hypothesis that PCR results are available faster, are more frequently positive, and may result in earlier adjustment of antimicrobial therapy. However, shorter time to result can only be fully exploited when the laboratory is adequately staffed for a 24 hour/7 day service, or when point of care/automated assay systems become available.

The transportation of wet gas fluid in carbon steel pipelines for onshore processing offers an economically attractive strategy. Although a substantial saving in capital cost can be realised, the risks of hydrate formation and corrosion damage are two of the main issues with such an approach. The standard industrial practice is to apply chemical solutions to reduce the risks. A thermodynamic hydrate inhibitor, such as monoethylene glycol (MEG) and corrosion inhibitors are commonly utilized to provide hydrate and corrosion control, respectively. Other production chemicals, such as an oxygen scavenger, may also be deployed as part of the risk management process. Consequently, the main challenge to the corrosion inhibitor is to provide corrosion protection throughout the production and processing facility while subjected to high temperatures in the MEG regeneration process and exposure to other production chemicals. Thermal stability and performance assessments should be an important aspect of the qualification process in the selection of corrosion inhibitors. This paper presents data from laboratory corrosion inhibitor evaluation programs, using thermally stressed MEG/chemicals under simulated wet gas pipeline operating conditions, which resulted in the successful qualification of a corrosion inhibitor for the production facility. In addition, the performance of oxygen scavengers for use in MEG systems is reviewed, including details of an oxygen scavenger that performs in lean MEG.

Chlamydia pneumoniae infection has been associated with asthma and atherosclerosis. Smooth muscle cells represent host cells for chlamydiae during chronic infection. In this study we demonstrated that C. pneumoniae infection of human smooth muscle cells in vitro increased production of interleukin 6 (IL-6) and basic fibroblast growth factor (bFGF) as shown by reverse transcription-PCR, immunoblotting, and enzyme-linked immunosorbent assay. In contrast, levels of platelet-derived growth factor A-chain mRNA were not affected after infection. The stimulation of bFGF and IL-6 production was most effective when viable chlamydiae were used as inoculum. Furthermore, inhibition of bacterial protein synthesis with chloramphenicol prevented up-regulation of IL-6 and bFGF in infected cells. Addition of IL-6 antibody to infected cultures diminished bFGF expression, indicating involvement of produced IL-6. These findings suggest that chlamydial infection of smooth muscle cells elicits a cytokine response that may contribute to structural remodeling of the airway wall in chronic asthma and to fibrous plaque formation in atherosclerosis.Chlamydia pneumoniae (in a recent paper renamed Chlamydophila pneumoniae) is an obligate intracellular bacterial pathogen that causes acute respiratory infections (9). Moreover, chronic or recurrent chlamydial infections have been associated with asthma and atherosclerosis. C. pneumoniae has a biphasic growth cycle. Infectious elementary bodies (EBs) enter the host cell and differentiate into reticulate bodies (RBs). These RBs divide by binary fission within the expanding endosome, resulting in development of an intracellular inclusion. After a period of growth, RBs reorganize into new EBs that are released by host cell lysis or exocytosis. Chronic infections are obviously associated with lytic and nonlytic phases in which chlamydiae do not replicate.Evidence for C. pneumoniae in asthma comes from serodiagnostic studies and culture (3,13,14). The association of asthma with elevated specific immunoglobulin G (IgG) antibodies seems to be strongest for nonatopic long-standing asthma (37). These studies suggest an important role for chronic infection as a promoting factor that would produce a tendency to severe chronic asthma. It is possible that chlamydiae amplify the inflammation in patients with early mild asthma, leading to permanent changes in the airways (37). Furthermore, C. pneumoniae can probably initiate adult-onset asthma (15). Activation of a synthetic phenotype of smooth muscle cells (SMC) plays an important role in the pathogenesis of asthma (17). Chronic inflammation and cycles of repair in chronic asthma lead to structural remodeling of the airway wall. This process is characterized by smooth muscle hyperplasia and hypertrophy and by thickening of the basement membrane with deposition of collagen types III and V (31, 33). The increase in the amount of SMC results in an enhanced contractile response and in irreversible airflow obstruction.The pathogenesis of atherosclerosis also invo...

Identification of ascitic bactDNA is an appropriate alternative to bacterial ascite culture for pathogen identification in patients at risk for SBP. Its prognostic relevance as a proposed marker of bacterial translocation for certain risk groups has to be further evaluated.

The large volume and diversified nanomedicine market, undergoing a rapid growth, relies not only on the creation and applicative exploration of nanocarrier-based medicines showing significant potential, but in particular, demands a quantitative assessment of their physicochemical properties. In this study, we demonstrate the in situ assessment of multifunctional biodegradable nanoparticle (NP) entries as core components of nanoscale drug delivery systems (NDDSs) by making use of analytical ultracentrifugation (AUC). We determine and elucidate the following characteristics of NPs in NDDSs: NP density and size, targeting dye functionality, encapsulated and free drug, surfactant, and also NP drug release dynamics, quantitatively interconnected to NP degradation. In concept, we demonstrate this by multidetection AUC experiments at variable speed and time profiles. We could verify the quantitative and accurate nature of AUC for assessment of NDDSs, that is, also future nanomedicines. This concerns modeled and real life solution application formats such as cell culture media and human serum.

A trunk of human cytidylate-phosphate-deoxyguanylate-binding protein/CXXC finger protein 1 (CFP1), immobilized onto an aminohexyl-Sepharose column, can be used as a preanalytical tool for the selective enrichment of bacterial DNA from mixed solutions with high amounts of human background DNA for nucleic acid amplification technique-based detection of pathogens. The transcriptional activator protein exhibits a high affinity for nonmethylated CpG dinucleotide motifs, which are differentially distributed in prokaryotic and higher eukaryotic genomes. The feasibility of the affinity chromatography (AC) step was tested with DNA from severely septic patients. AC using 16S rRNA gene primers substantially increased PCR sensitivity. Approximately 90% of eukaryotic DNA was removed, which significantly increased the signal-to-noise ratio. Threshold cycle values revealed that sensitivity was elevated at least 10-fold. The change in the ratio of bacterial DNA to human DNA increased from 26% to 74% the likelihood of culture-independent PCR-based identification of bacterial presence. Compared to the results seen with blood culture (which is the clinical gold standard for systemic infections, exhibiting 28% positives), the combination of AC and PCR achieves a significant increase in sensitivity and contributes to shortening the time to results for the initiation of guided antibiotic therapy.The routine methods utilized in clinical microbiology laboratories, such as the demonstration of the presence of pathogens in samples from patients suspected of systemic infections, are predominantly culture based and exhibit drawbacks due to antibiotic treatment of the patient prior to sample withdrawal (e.g., from blood, wound swabs, or cerebrospinal fluid), low abundance of causative agents in exclusive samples, and, frequently, noncultivable or growth-repressed organisms. The gold standard, blood culture (BC), for example, returns negative results for 80% to 90% of all invasive infection incidents even when the presence of an infection is obvious from the medical history and additional clinical diagnostics. Cultural results usually take periods of 24 to 72 h to be obtained, whereas a sample can be reliably declared negative within up to 7 days' incubation (26, 27). These results are therefore only the basis for further microbial diagnostics, e.g., species differentiation and/or generation of antibacterial susceptibility profiles, which are also laborious and time-consuming processes. The derivation of an antibiotic therapy from the results obtained with the gold standard (e.g., in the case of sepsis) within the first "golden hours" would determine the course and prognosis for the case (17); however, such an approach is currently not feasible, while adequate (directed) and early antibiotic therapies are mandatory for the avoidance of mortal outcomes (7,8,11,28). In the case of sepsis, an increase of mortality of 7% to 8% per hour was proven after delay of adequate antibiotic treatment (12). Moreover, the rise in the rate of infective disea...

PCR assays designed for the diagnosis of invasive aspergillosis (IA) in high-risk patients have to detect minute amounts of target DNA to reach sufficient analytical sensitivity to be of clinical use. This prospective study assessed the use of a novel strategy for selective pathogen DNA enrichment for enhancing the performance of diagnostic PCR in a direct comparison with a highly sensitive in-house quantitative PCR (qPCR) assay and the galactomannan enzyme-linked immunosorbent assay (ELISA). Surprisingly, and in contrast to experience with other patient groups, the novel protocol for selective pathogen DNA enrichment did not enhance but instead significantly impaired sensitivity. This could be explained by the small amounts of host DNA in the specimens, which were derived mostly from severely neutropenic patients. In the qPCR assay, positive samples required an average of 43.5 amplification cycles (range, 39.2 to 50) for detection in the in-house PCR. Repetitive testing of selected samples showed test positivity to be variable, most likely due to the small amounts of target DNA. Despite this, the in-house protocol proved helpful in the diagnosis of IA, detecting 2 out of 3 patients with probable IA and 10 out of 19 patients with possible IA. Our results underline the necessity for diagnostic PCR protocols that help diagnose IA to be highly sensitive and show that selective pathogen DNA enrichment using affinity purification may not be useful in severely neutropenic patients.

Summary This study investigates the oxygen-scavenging behavior of bisulfite ions in monoethylene glycol (MEG)/water mixtures at concentrations commonly found in gas-transportation pipelines. Temperatures and pH values were varied. The influence of transition-metal (TM) ions to catalyze the bisulfite oxygen scavenging was studied. Experimental results indicate that MEG significantly inhibits bisulfite oxygen removal, which is hindered at low pH values and, to some extent, temperature. TMs can accelerate the oxygen-scavenging reaction in pH-unadjusted solutions, although the rate was still lower than that of the pH-adjusted solutions. The possible mechanism for such behavior and industrial implications are discussed.