Distinct Prostate Cancer Survival Outcomes in Firefighters: A Population-Based Study.

Introduction: Survival outcomes for prostate cancer among specific occupational groups prone to regular medical check-ups vis-à-vis the general population have been understudied. For firefighters, a demographic subject to rigorous medical evaluations, possessing above-average medical expertise, and exposed to specific carcinogens of interest, prostate cancer survival in the US has never been studied. Methods: We conducted a retrospective study, utilizing data from the Florida Cancer Data System spanning 2004 to 2014, coupled with firefighter certification records from the Florida State Fire Marshal's Office. Our study cohort consisted of 1058 prostate cancer cases among firefighters as well as prostate cases for the Florida general population (n = 150,623). We compared cause-specific survival between the two using Cox regression models adjusted for demographics and clinical characteristics, including PSA levels, Gleason scores, and treatment modalities. Results: Firefighters demonstrated a higher five-year cause-specific survival rate (96.1%, 95% CI: 94.7-97.1%) than the general population (94.2%, 95%CI: 94.1-94.3%). Overall, firefighters' diagnoses were established at younger ages (median age 63 vs. 67 in the general population), exhibited a higher proportion of localized stage cancers (84.7% vs. 81.1%), and had a greater utilization of surgery (46.4% vs. 37.6%), a treatment modality with a high success rate but potential side effects. In multivariable analysis, firefighters displayed a survival advantage for localized stage (adjusted hazard ratio [aHR] = 0.53; 95%CI: 0.34-0.82). However, for regional or distant stages, firefighters aged 65 and above exhibited a higher risk of death (aHR = 1.84; 95% CI: 1.18-2.86) than the general population. Conclusion: Firefighters experience enhanced prostate cancer survival, primarily in cases diagnosed at localized stages, likely due to increased PSA testing. Nonetheless, for regional or distant stage, survival among older firefighters' lags behind that of the general population. Further investigations are warranted to unravel factors influencing the development of aggressive disease beyond PSA and Gleason scores in this population, as well as to assess the impact of a higher rate of surgical treatment on firefighters' quality of life.

Lung cancer survival among Florida male firefighters.

Introduction: Lung cancer is a leading cause of cancer incidence and death in the United States. Although most firefighters are fit and do not smoke, they are exposed to many known carcinogens during and in the aftermath of firefighting activities. Comprehensive epidemiologic investigations on lung cancer survival for both career and volunteer firefighters have not been undertaken. Methods: Data from the Florida Cancer Data System (1981-2014) were linked with firefighter certification records from the Florida State Fire Marshal's Office to identify all patients of this occupational group; lung cancer cause-specific survival data were compared with other occupational groups using Cox regression models with occupation as the main effect. Adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) were calculated. Results: Out of 210,541 male lung cancer cases diagnosed in Florida (1981-2014), 761 were firefighters (604 career, 157 volunteer). Lung cancer death was similar between volunteer (75.2%) and career firefighters (74.0%) but lower than non-firefighters (80.0%). Survival at 5 years was higher among firefighters (29.7%; career: 30.3%; volunteer: 27.4%) than non-firefighters (23.8%). In a multivariable model, compared with non-firefighters, firefighters have significantly higher cause-specific survival (aHR = 0.84; 95% CI: 0.77-0.91; p < 0.001). However, there were no significant survival differences between career and volunteer firefighters (1.14; 0.93-1.39; p = 0.213). In a separate multivariable model with firefighters as the comparator, other broad occupational groups had significantly lower cause-specific survival [white collar: 1.11 (1.02-1.21); blue collar: 1.15 (1.05-1.25); service: 1.13 (1.03-1.25); others/unknown: 1.21 (1.12-1.32); all p-values < 0.02]. Conclusion: Lung cancer survival is significantly higher among firefighters compared with non-firefighters, but there is no significant difference between career and volunteer firefighters. Improved survival for firefighters might be due to a healthy worker effect, lower smoking prevalence relative to other worker groups, and possibly superior treatment adherence and compliance. Many firefighters are cross-trained as EMTs/paramedics and possess a level of medical knowledge that may favorably impact treatment engagement and better navigation of complex cancer care.

An examination of psychometric properties of study quality assessment scales in meta-analysis: Rasch measurement model applied to the firefighter cancer literature.

Most existing quality scales have been developed with minimal attention to accepted standards of psychometric properties. Even for those that have been used widely in medical research, limited evidence exists supporting their psychometric properties. The focus of our current study is to address this gap by evaluating the psychometrics properties of two existing quality scales that are frequently used in cancer observational research: (1) Item Bank on Risk of Bias and Precision of Observational Studies developed by the Research Triangle Institute (RTI) International and (2) Newcastle-Ottawa Quality Assessment Scale (NOQAS). We used the Rasch measurement model to evaluate the psychometric properties of two quality scales based on the ratings of 49 studies that examine firefighters' cancer incidence and mortality. Our study found that RTI and NOQAS have an acceptable item reliability. Two raters were consistent in their assessment, demonstrating high interrater reliability. We also found that NOQAS has more items that show better fit than the RTI scale. The NOQAS produced lower study quality scores with a smaller variation, suggesting that NOQAS items are much easier to rate. Our findings accord with a previous study, which conclude that the RTI scale was harder to apply and thus produces more heterogenous quality scores than NOQAS. Although both RTI and NOQAS showed high item reliability, NOQAS items are better fit to the underlying construct, showing higher validity of internal structure and stronger psychometric properties. The current study adds to our understanding of the psychometric properties of NOQAS and RTI scales for future meta-analyses of observational studies, particularly in the firefighter cancer literature.

Effect of Sample Sources on Heavy Metal Concentration Measured in Beta Vulgaris Organs.

Aim: Heavy metal concentration [mg/dL, MP] in soil and the transfer to vegetable organs may have a sampling effect. We compared the [MP] in soil and organ samples of Beta vulgaris collected in sites with socioeconomic differences potentially inducing phytotoxicity. Materials and Methods: Samples of Beta vulgaris and soils (n = 4 per sample of soil and plant material) were randomly collected from two distant geographic areas (Mosquera and Sibaté, Cundinamarca, Colombia). We determined the [MP] using acid digestion of HCl : HNO3 [1 : 1]; the [MP] was obtained by atomic absorption in Varian AA-140 and Shimadzu AA-7000 equipment. A two-way ANOVA estimated the effect (partial η2) of the sampling site and metal type on the [MP] and transfer to the vegetable. Results: In Sibaté, the means (SD) of As_1.44 (0.18), Co_1.09 (0.51), Cr_6.21 (0.33), Ni_0.22 (0.02), and Pb_4.17 (0.87) were higher than in Mosquera (As_1.06 (0.21), Co_0.81 (0.19), Cr_3.72 (0.51), Ni_0.13 (0.04), and Pb_1.69 (0.40)) (p value <0.05). The effect of the interaction between the metal type and Beta vulgaris organs on the [MP] (0.801) in Sibaté was more meaningful than in Mosquera (0.430). Additionally, there was a strong correlation (Spearman's ρ > 0.8, p value <0.001) between [MP_soil] and [MP_plants] and between the transfer of metals to the plant and to the leaves. Discussion. The sampling location has a differential effect on the [MP] in soil and the transfer to Beta vulgaris. Given the differential effect described, the monitoring and phytoremediation strategies must be adjusted to scenarios with potentially phytotoxic conditions.

Inhibition of Lysyl Oxidase with ß-aminopropionitrile Improves Venous Adaptation after Arteriovenous Fistula Creation.

BACKGROUND: The arteriovenous fistula (AVF) is the preferred hemodialysis access for end-stage renal disease (ESRD) patients. Yet, establishment of a functional AVF presents a challenge, even for the most experienced surgeons, since postoperative stenosis frequently occludes the AVF. Stenosis results from the loss of compliance in fibrotic areas of the fistula which turns intimal hyperplasia into an occlusive feature. Fibrotic remodeling depends on deposition and crosslinking of collagen by lysyl oxidase (LOX), an enzyme that catalyzes the deamination of lysine and hydroxylysine residues, facilitating intra/intermolecular covalent bonds. We postulate that pharmacological inhibition of lysyl oxidase (LOX) increases postoperative venous compliance and prevents stenosis in a rat AVF model. METHODS: LOX gene expression and vascular localization were assayed in rat AVFs and human pre-access veins, respectively. Collagen crosslinking was measured in humans AVFs that matured or failed, and in rat AVFs treated with ß-aminopropionitrile (BAPN), an irreversible LOX inhibitor. BAPN was either injected systemically or delivered locally around rat AVFs using nanofiber scaffolds. The major endpoints were AVF blood flow, wall fibrosis, collagen crosslinking, and vascular distensibility. RESULTS: Non-maturation of human AVFs was associated with higher LOX deposition in pre-access veins (N=20, P=0.029), and increased trivalent crosslinks (N=18, P=0.027) in human AVF tissues. Systemic and local inhibition of LOX increased AVF distensibility, while reducing wall fibrosis and collagen crosslinking in rat fistulas. CONCLUSIONS: Our results demonstrate that BAPN-mediated inhibition of LOX significantly improves vascular remodeling in experimental fistulas.

A Genetic Model of Constitutively Active Integrin CD11b/CD18.

Pharmacological activation of integrin CD11b/CD18 (αMß2, Mac-1, and CR3) shows anti-inflammatory benefits in a variety of animal models of human disease, and it is a novel therapeutic strategy. Reasoning that genetic models can provide an orthogonal and direct system for the mechanistic study of CD11b agonism, we present in this study, to our knowledge, a novel knock-in model of constitutive active CD11b in mice. We genetically targeted the Itgam gene (which codes for CD11b) to introduce a point mutation that results in the I332G substitution in the protein. The I332G mutation in CD11b promotes an active, higher-affinity conformation of the ligand-binding I/A-domain (CD11b αA-domain). In vitro, this mutation increased adhesion of knock-in neutrophils to fibrinogen and decreased neutrophil chemotaxis to a formyl-Met-Leu-Phe gradient. In vivo, CD11bI332G animals showed a reduction in recruitment of neutrophils and macrophages in a model of sterile peritonitis. This genetic activation of CD11b also protected against development of atherosclerosis in the setting of hyperlipidemia via reduction of macrophage recruitment into atherosclerotic lesions. Thus, our animal model of constitutive genetic activation of CD11b can be a useful tool for the study of integrin activation and its potential contribution to modulating leukocyte recruitment and alleviating different inflammatory diseases.

Neonatal hyperoxia exposure induces aortic biomechanical alterations and cardiac dysfunction in juvenile rats.

Supplemental oxygen (O2 ) therapy in preterm infants impairs lung development, but the impact of O2 on long-term systemic vascular structure and function has not been well-explored. The present study tested the hypothesis that neonatal O2 therapy induces long-term structural and functional alterations in the systemic vasculature, resulting in vascular stiffness observed in children and young adults born preterm. Newborn Sprague-Dawley rats were exposed to normoxia (21% O2 ) or hyperoxia (85% O2 ) for 1 and 3 weeks. A subgroup exposed to 3 weeks hyperoxia was recovered in normoxia for an additional 3 weeks. Aortic stiffness was assessed by pulse wave velocity (PWV) using Doppler ultrasound and pressure myography. Aorta remodeling was assessed by collagen deposition and expression. Left ventricular (LV) function was assessed by echocardiography. We found that neonatal hyperoxia exposure increased vascular stiffness at 3 weeks, which persisted after normoxic recovery at 6 weeks of age. These findings were accompanied by increased PWV, aortic remodeling, and altered LV function as evidenced by decreased ejection fraction, cardiac output, and stroke volume. Importantly, these functional changes were associated with increased collagen deposition in the aorta. Together, these findings demonstrate that neonatal hyperoxia induces early and sustained biomechanical alterations in the systemic vasculature and impairs LV function. Early identification of preterm infants who are at risk of developing systemic vascular dysfunction will be crucial in developing targeted prevention strategies that may improve the long-term cardiovascular outcomes in this vulnerable population.

c-Kit deficiency impairs nitric oxide signaling in smooth muscle cells.

INTRODUCTION: Receptor tyrosine kinases have been implicated in various vascular remodeling processes and cardiovascular disease. However, their role in the regulation of vascular tone is poorly understood. Herein, we evaluate the contribution of c-Kit signaling to vasoactive responses. METHODS: The vascular reactivity of mesenteric arteries was assessed under isobaric conditions in c-Kit deficient (KitW/W-v) and littermate control mice (Kit+/+) using pressure myography. Protein levels of soluble guanylyl cyclase beta 1 (sGCß1) were quantified by Western blot. Mean arterial pressure was measured after high salt (8% NaCl) diet treatment using the tail-cuff method. RESULTS: Smooth muscle cells (SMCs) from c-Kit deficient mice showed a 5-fold downregulation of sGCß1 compared to controls. Endothelium-dependent relaxation of mesenteric arteries demonstrated a predominance of prostanoid vs. nitric oxide (NO) signaling in both animal groups. The dependence on prostanoid-induced dilation was higher in c-Kit mutant mice than in controls, as indicated by a significant impairment in vasorelaxation with indomethacin with respect to the latter. Endothelium-independent relaxation showed significant dysfunction of NO signaling in c-Kit deficient SMCs compared to controls. Mesenteric artery dilation was rescued by addition of a cGMP analog, but not with a NO donor, indicating a deficiency in cGMP production in c-Kit deficient SMCs. Finally, c-Kit deficient mice developed higher blood pressure on an 8% NaCl diet compared to their control littermates. CONCLUSION: c-Kit deficiency inhibits NO signaling in SMCs. The existence of this c-Kit/sGC signaling axis may be relevant for vascular reactivity and remodeling.

Performance of the T2Bacteria Panel for Diagnosing Bloodstream Infections: A Diagnostic Accuracy Study.

Background: Blood cultures, the gold standard for diagnosing bloodstream infections (BSIs), are insensitive and limited by prolonged time to results. The T2Bacteria Panel (T2 Biosystems) is a direct-from-blood, nonculture test that identifies the most common ESKAPE bacteria (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli). Objective: To assess performance of the T2Bacteria Panel in diagnosing suspected BSIs in adults. Design: Prospective patient enrollment (8 December 2015 through 4 August 2017). Setting: Eleven U.S. hospitals. Patients: 1427 patients for whom blood cultures were ordered as standard of care. Intervention: Paired blood culture and T2Bacteria testing. Measurements: Performance of T2Bacteria compared with a single set of blood cultures in diagnosing proven, probable, and possible BSIs caused by T2Bacteria-targeted organisms. Results: Blood culture and T2Bacteria results were positive for targeted bacteria in 3% (39 of 1427) and 13% (181 of 1427) of patients, respectively. Mean times from start of blood culture incubation to positivity and species identification were 38.5 (SD, 32.8) and 71.7 (SD, 39.3) hours, respectively. Mean times to species identification with T2Bacteria were 3.61 (SD, 0.2) to 7.70 (SD, 1.38) hours, depending on the number of samples tested. Per-patient sensitivity and specificity of T2Bacteria for proven BSIs were 90% (95% CI, 76% to 96%) and 90% (CI, 88% to 91%), respectively; the negative predictive value was 99.7% (1242 of 1246). The rate of negative blood cultures with a positive T2Bacteria result was 10% (146 of 1427); 60% (88 of 146) of such results were associated with probable (n = 62) or possible (n = 26) BSIs. If probable BSIs and both probable and possible BSIs were assumed to be true positives missed by blood culture, per-patient specificity of T2Bacteria was 94% and 96%, respectively. Limitation: Low prevalence of positive blood cultures, collection of a single set of culture specimens, and inability of T2Bacteria to detect nontargeted pathogens. Conclusion: The T2Bacteria Panel rapidly and accurately diagnoses BSIs caused by 5 common bacteria. Primary Funding Source: T2 Biosystems.

Immature and Mature Collagen Crosslinks Quantification Using High-Performance Liquid Chromatography and High-Resolution Mass Spectrometry in Orbitrap™.

Different methodologies for collagen quantification have been described in the past. Introduction of mass spectrometry combined with high-performance liquid chromatography (HPLC) is a high-resolution tool, which has generated novel applications in biomedical research. In this study, HPLC coupled to electrospray ionization (ESI) tandem mass spectrometry (HPLC-ESI-MS/MS) was used to characterize tissue samples from AVFs done in rats. These findings helped create a protocol for identifying and quantifying components of immature and mature collagen crosslink moieties. Two different internal standards were used: epinephrine and pyridoxine. Quantification curves were drawn by means of these standards. The goal of the experiment was to achieve accurate quantification with the minimum amount of sample. Time and cost of experiment were considerably minimized. Up to date, this method has not been tested for crosslinking quantification.

Transcriptomics of Human Arteriovenous Fistula Failure: Genes Associated With Nonmaturation.

RATIONALE & OBJECTIVE: Improving arteriovenous fistula (AVF) outcomes requires better understanding of the biology underlying maturation or failure. Our current knowledge of maturation relies on extrapolation from other vascular pathologies, which does not incorporate unique aspects of AVF remodeling. This study compares the RNA expression of pre-access (native) veins and AVFs with distinct maturation outcomes. STUDY DESIGN: Case-control study. SETTING & PARTICIPANTS: 64 patients undergoing 2-stage AVF surgeries at a single center. 19 native veins and 19 AVF samples were analyzed using RNA sequencing (RNA-seq). 58 native veins were studied using real-time polymerase chain reaction; 45, using immunohistochemistry; and 19, using Western blot analysis. PREDICTOR: RNA expression in native veins and AVFs. OUTCOME: Anatomic nonmaturation, defined as an AVF that never achieved an internal diameter ≥ 6mm. ANALYTICAL APPROACH: Pre-access native veins and AVF samples were obtained from patients undergoing 2-stage AVF creation. Veins that subsequently matured or failed after access creation were analyzed using RNA-seq to search for genes associated with maturation failure. Genes associated with nonmaturation were confirmed using real-time polymerase chain reaction, immunohistochemistry, and Western blot analysis. In addition, the association between pre-access gene expression and postoperative morphology was evaluated. RNA-seq was also performed on AVFs to search for transcriptional differences between AVFs that matured and those that failed at the time of transposition. RESULTS: Pro-inflammatory genes (CSF3R, FPR1, S100A8, S100A9, and VNN2) were upregulated in pre-access veins that failed (false discovery rate < 0.05), and their expression colocalized to smooth muscle cells. Expression of S100A8 and S100A9 correlated with postoperative intimal hyperplasia and the product of medial fibrosis and intimal hyperplasia (r=0.32-0.38; P < 0.05). AVFs that matured or failed were transcriptionally similar at the time of transposition. LIMITATIONS: Small sample size, analysis of only upper-arm veins and transposed fistulas. CONCLUSIONS: Increased expression of proinflammatory genes in pre-access veins appears to be associated with greater risk for AVF nonmaturation.

Near point-of-care adoption of Cepheid Xpert® Flu/RSV XC testing within an integrated healthcare delivery network.

Flu/RSV testing was implemented in out-patient clinic-based physician office laboratories throughout Pennsylvania. On-site testing reduced the collect-to-result time by 70% when compared to testing in a centralized core laboratory; over- or under-treatment for influenza A and B (measured by anti-viral prescription) was reduced by 15% (P < 0.0001). Antimicrobial prescription was not affected by on-site testing.

Multicenter Evaluation of the Accelerate PhenoTest BC Kit for Rapid Identification and Phenotypic Antimicrobial Susceptibility Testing Using Morphokinetic Cellular Analysis.

We describe results from a multicenter study evaluating the Accelerate Pheno system, a first of its kind diagnostic system that rapidly identifies common bloodstream pathogens from positive blood cultures within 90 min and determines bacterial phenotypic antimicrobial susceptibility testing (AST) results within ∼7 h. A combination of fresh clinical and seeded blood cultures were tested, and results from the Accelerate Pheno system were compared to Vitek 2 results for identification (ID) and broth microdilution or disk diffusion for AST. The Accelerate Pheno system accurately identified 14 common bacterial pathogens and two Candida spp. with sensitivities ranging from 94.6 to 100%. Of fresh positive blood cultures, 89% received a monomicrobial call with a positive predictive value of 97.3%. Six common Gram-positive cocci were evaluated for ID. Five were tested against eight antibiotics, two resistance phenotypes (methicillin-resistant Staphylococcus aureus and Staphylococcus spp. [MRSA/MRS]), and inducible clindamycin resistance (MLSb). From the 4,142 AST results, the overall essential agreement (EA) and categorical agreement (CA) were 97.6% and 97.9%, respectively. Overall very major error (VME), major error (ME), and minor error (mE) rates were 1.0%, 0.7%, and 1.3%, respectively. Eight species of Gram-negative rods were evaluated against 15 antibiotics. From the 6,331 AST results, overall EA and CA were 95.4% and 94.3%, respectively. Overall VME, ME, and mE rates were 0.5%, 0.9%, and 4.8%, respectively. The Accelerate Pheno system has the unique ability to identify and provide phenotypic MIC and categorical AST results in a few hours directly from positive blood culture bottles and support accurate antimicrobial adjustment.

Fibrotic Venous Remodeling and Nonmaturation of Arteriovenous Fistulas.

The frequency of primary failure in arteriovenous fistulas (AVFs) remains unacceptably high. This lack of improvement is due in part to a poor understanding of the pathobiology underlying AVF nonmaturation. This observational study quantified the progression of three vascular features, medial fibrosis, intimal hyperplasia (IH), and collagen fiber organization, during early AVF remodeling and evaluated the associations thereof with AVF nonmaturation. We obtained venous samples from patients undergoing two-stage upper-arm AVF surgeries at a single center, including intraoperative veins at the first-stage access creation surgery and AVFs at the second-stage transposition procedure. Paired venous samples from both stages were used to evaluate change in these vascular features after anastomosis. Anatomic nonmaturation (AVF diameter never ≥6 mm) occurred in 39 of 161 (24%) patients. Neither preexisting fibrosis nor IH predicted AVF outcomes. Postoperative medial fibrosis associated with nonmaturation (odds ratio [OR], 1.55; 95% confidence interval [95% CI], 1.05 to 2.30; P=0.03, per 10% absolute increase in fibrosis), whereas postoperative IH only associated with failure in those individuals with medial fibrosis over the population's median value (OR, 2.63; 95% CI, 1.07 to 6.46; P=0.04, per increase of 1 in the intima/media ratio). Analysis of postoperative medial collagen organization revealed that circumferential alignment of fibers around the lumen associated with AVF nonmaturation (OR, 1.38; 95% CI, 1.03 to 1.84; P=0.03, per 10° increase in angle). This study demonstrates that excessive fibrotic remodeling of the vein after AVF creation is an important risk factor for nonmaturation and that high medial fibrosis determines the stenotic potential of IH.

Loss of c-Kit function impairs arteriogenesis in a mouse model of hindlimb ischemia.

BACKGROUND: Arteriogenesis is a process whereby collateral vessels remodel usually in response to increased blood flow and/or wall stress. Remodeling of collaterals can function as a natural bypass to alleviate ischemia during arterial occlusion. Here we used a genetic approach to investigate possible roles of tyrosine receptor c-Kit in arteriogenesis. METHODS: Mutant mice with loss of c-Kit function (KitW/W-v), and controls were subjected to hindlimb ischemia. Blood flow recovery was evaluated pre-, post-, and weekly after ischemia. Foot ischemic damage and function were assessed between days 1 to 14 post-ischemia while collaterals remodeling were measured 28 days post-ischemia. Both groups of mice also were subjected to wild type bone marrow cells transplantation 3 weeks before hindlimb ischemia to evaluate possible contributions of defective bone marrow c-Kit expression on vascular recovery. RESULTS: KitW/W-v mice displayed impaired blood flow recovery, greater ischemic damage and foot dysfunction after ischemia compared to controls. KitW/W-v mice also demonstrated impaired collateral remodeling consistent with flow recovery findings. Because arteriogenesis is a biological process that involves bone marrow-derived cells, we investigated which source of c-Kit signaling (bone marrow or vascular) plays a major role in arteriogenesis. KitW/W-v mice transplanted with bone marrow wild type cells exhibited similar phenotype of impaired blood flow recovery, greater tissue ischemic damage and foot dysfunction as nontransplanted KitW/W-v mice. CONCLUSION: This study provides evidence that c-Kit signaling is required during arteriogenesis. Also, it strongly suggests a vascular role for c-Kit signaling because rescue of systemic c-Kit activity by bone marrow transplantation did not augment the functional recovery of KitW/W-v mouse hindlimbs.

Multicenter Evaluation of the Xpert MRSA NxG Assay for Detection of Methicillin-Resistant Staphylococcus aureus in Nasal Swabs.

Health care-associated methicillin-resistant Staphylococcus aureus (MRSA) infections are a burden on the health care system. Clinical laboratories play a key role in reducing this burden, as the timely identification of MRSA colonization or infection facilitates infection control practices that are effective at limiting invasive MRSA infections. The Xpert MRSA NxG assay recently received FDA clearance for the direct detection of MRSA from nasal swabs. This multicenter study evaluated the clinical performance characteristics of the Xpert MRSA NxG assay with prospectively collected rayon nasal swabs (n = 1,103) and flocked swab (ESwab) nasal specimens (n = 846). Culture-based identification methods and antimicrobial susceptibility testing were used as the reference standards for comparison. According to the reference method, the positivity rates for MRSA in the population evaluated were 11.1% (122/1,103) for rayon swabs and 11.6% (98/846) for flocked swabs. The overall sensitivity and specificity of the rayon swabs were 91.0% (95% confidence interval [CI], 84.6 to 94.9%) and 96.9% (95% CI, 95.7 to 97.8%), respectively, across eight testing sites. The flocked swab specimens were 92.9% sensitive (95% CI, 86.0 to 96.5%) and 97.6% specific (95% CI, 96.2 to 98.5%) for MRSA detection across six testing sites. The sensitivity and specificity of the combined flocked and rayon swab data were 91.8% (95% CI, 87.4 to 94.8%) and 97.2% (95% CI, 96.3 to 97.9%), respectively. The positive predictive value (PPV) for rayon swabs was 78.7%, versus 83.5% for ESwabs. The negative predictive values (NPVs) for rayon swabs and ESwab specimens were 98.9% and 99.1%, respectively. In conclusion, the Xpert MRSA NxG assay is a sensitive and specific assay for the direct detection of MRSA from nasal swab specimens.

c-Kit modifies the inflammatory status of smooth muscle cells.

BACKGROUND: c-Kit is a receptor tyrosine kinase present in multiple cell types, including vascular smooth muscle cells (SMC). However, little is known about how c-Kit influences SMC biology and vascular pathogenesis. METHODS: High-throughput microarray assays and in silico pathway analysis were used to identify differentially expressed genes between primary c-Kit deficient (KitW/W-v) and control (Kit+/+) SMC. Quantitative real-time RT-PCR and functional assays further confirmed the differences in gene expression and pro-inflammatory pathway regulation between both SMC populations. RESULTS: The microarray analysis revealed elevated NF-κB gene expression secondary to the loss of c-Kit that affects both the canonical and alternative NF-κB pathways. Upon stimulation with an oxidized phospholipid as pro-inflammatory agent, c-Kit deficient SMC displayed enhanced NF-κB transcriptional activity, higher phosphorylated/total p65 ratio, and increased protein expression of NF-κB regulated pro-inflammatory mediators with respect to cells from control mice. The pro-inflammatory phenotype of mutant cells was ameliorated after restoring c-Kit activity using lentiviral transduction. Functional assays further demonstrated that c-Kit suppresses NF-κB activity in SMC in a TGFß-activated kinase 1 (TAK1) and Nemo-like kinase (NLK) dependent manner. DISCUSSION: Our study suggests a novel mechanism by which c-Kit suppresses NF-κB regulated pathways in SMC to prevent their pro-inflammatory transformation.

Multicenter Evaluation of MRSASelect II Chromogenic Agar for Identification of Methicillin-Resistant Staphylococcus aureus from Wound and Nasal Specimens.

Hospitals strive to reduce methicillin-resistant Staphylococcus aureus (MRSA) prevalence via active surveillance of inpatient populations. Rapid and inexpensive screening methods are utilized when molecular methods are not operationally feasible. In this multisite clinical trial, the utility of Bio-Rad's MRSASelect II was evaluated for MRSA identification from remnant nares and wound swabs. The prevalence of MRSA was 11.1% (n = 1,384) from nares samples and 18.1% (n = 842) from wound samples. MRSASelect II had an overall concordance of 95.4% (confidence interval [CI] = 94.5% to 96.2%) compared to a broth-enriched reference standard. Comparisons between results, stratified by examination times, exhibited a nonsignificant trend toward increased positivity at prolonged incubation times. Cefoxitin screening of colonies directly from MRSASelect II was 96.7% (95.8% to 97.3%) concordant compared to testing of colonies following broth enrichment. A comparison of MRSASelect and MRSASelect II revealed no statistical differences; however, the latter exhibited earlier positivity, greater selectivity, and more intense indicator staining, which resulted in facilitated differentiation of positive results. MRSASelect II agar is a simple, rapid, and robust method to routinely screen patients for MRSA colonization without the need for additional testing.

Flavin adenine dinucleotide structural motifs: from solution to gas phase.

Flavin adenine dinucleotide (FAD) is involved in important metabolic reactions where the biological function is intrinsically related to changes in conformation. In the present work, FAD conformational changes were studied in solution and in gas phase by measuring the fluorescence decay time and ion-neutral collision cross sections (CCS, in a trapped ion mobility spectrometer, TIMS) as a function of the solvent conditions (i.e., organic content) and gas-phase collisional partner (i.e., N2 doped with organic molecules). Changes in the fluorescence decay suggest that FAD can exist in four conformations in solution, where the abundance of the extended conformations increases with the organic content. TIMS-MS experiments showed that FAD can exist in the gas phase as deprotonated (M = C27H31N9O15P2) and protonated forms (M = C27H33N9O15P2) and that multiple conformations (up to 12) can be observed as a function of the starting solution for the [M + H](+) and [M + Na](+)molecular ions. In addition, changes in the relative abundances of the gas-phase structures were observed from a "stack" to a "close" conformation when organic molecules were introduced in the TIMS cell as collision partners. Candidate structures optimized at the DFT/B3LYP/6-31G(d,p) were proposed for each IMS band, and results showed that the most abundant IMS band corresponds to the most stable candidate structure. Solution and gas-phase experiments suggest that the driving force that stabilizes the different conformations is based on the interaction of the adenine and isoalloxazine rings that can be tailored by the "solvation" effect created with the organic molecules.

Effects of an epidermal growth factor receptor-based cancer vaccine on wound healing and inflammation processes in murine experimental models.

Anti-epidermal growth factor receptor (EGFR) therapies have been proven clinically effective for a variety of epithelial tumours. Vaccination of mice with the extracellular domain (ECD) of autologous EGFR overcomes the tolerance to self-EGFR and has antimetastatic effect on EGFR+ tumour. Because EGF/EGFR-signalling plays an important role in the inflammation stage of wound healing, the main objective of this study was to explore the possible role of murine (m) EGFR-ECD vaccine in the croton-oil-induced ear oedema and wound healing process in mice as autologous experimental models, mimicking the possible post-surgical wound complication in patients treated with human EGFR-ECD/VSSP vaccine. Mice were intramuscularly immunised four times; biweekly with the mEGFR-ECD/VSSP/Mont. Seven days later, an 8 mm diameter, full-thickness skin wound was created on the back of each animal. Immunisation induced a strong specific humoral response against the mEGFR-ECD protein and a DTH dose-response curve but interestingly, animals treated with mEGFR-ECD/VSSP/Mont had similar inflammatory and healing speed responses compared to control ones. These data suggest that application of mEGFR-ECD/VSSP vaccine as a therapeutic approach in cancer patients could not elicit a poor healing process after surgery.