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171.
The utility of empirical combination antimicrobial therapy for Gram-negative bloodstream infection (BSI) remains unclear. This retrospective, quasi-experimental matched cohort study examined the impact of empirical combination therapy on mortality in patients with Gram-negative BSI. Hospitalized adults with Gram-negative BSI from 1 January 2010 to 31 December 2013 at Palmetto Health Hospitals in Columbia, SC, USA were identified. Patients receiving combination therapy or beta-lactam monotherapy were matched 1:1 based on age, sex and Bloodstream Infection Mortality Risk Score (BSIMRS). Multivariate Cox proportional hazards regression with propensity score adjustment was used to examine overall 28–day mortality and within predefined BSIMRS categories (<5 and ≥5). A total of 380 patients receiving combination therapy or monotherapy for Gram-negative BSI were included in the study. Median age was 66 years and 204 (54%) were female. Overall, 28-day mortality in patients who received combination therapy and monotherapy was 13% and 15%, respectively (P?=?0.51). After stratification by BSIMRS, mortality in both combination therapy and monotherapy groups was 1.1% in patients with BSIMRS <5 (P?=?0.98) and 27% and 32%, respectively, in patients with BSIMRS ≥5 (P?=?0.47). After adjusting for propensity to receive combination therapy, risk of mortality was not significantly different for combination therapy compared to monotherapy (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.51–1.60). This finding persisted for both subgroups of BSIMRS <5 (HR 0.96, 95% CI 0.04–24.28) and BSIMRS ≥5 (HR 0.83, 95% CI 0.46–1.48). There is no survival benefit from empirical combination therapy over monotherapy in patients with Gram-negative BSI, regardless of predicted prognosis at initial presentation.  相似文献   
172.
Evidence suggests exposure of nicotine-containing e-cigarette aerosol to nonusers leads to systemic absorption of nicotine. However, no studies have examined acute secondhand exposures that occur in public settings. Here, we measured the serum, saliva and urine of nonusers pre- and post-exposure to nicotine via e-cigarette aerosol. Secondarily, we recorded factors affecting the exposure.Six nonusers of nicotine-containing products were exposed to secondhand aerosol from ad libitum e-cigarette use by three e-cigarette users for 2?h during two separate sessions (disposables, tank-style). Pre-exposure (baseline) and post-exposure peak levels (Cmax) of cotinine were measured in nonusers’ serum, saliva, and urine over a 6-hour follow-up, plus a saliva sample the following morning. We also measured solution consumption, nicotine concentration, and pH, along with use behavior.Baseline cotinine levels were higher than typical for the US population (median serum session one?=?0.089?ng/ml; session two?=?0.052?ng/ml). Systemic absorption of nicotine occurred in nonusers with baselines indicative of no/low tobacco exposure, but not in nonusers with elevated baselines. Median changes in cotinine for disposable exposure were 0.007?ng/ml serum, 0.033?ng/ml saliva, and 0.316?ng/mg creatinine in urine. For tank-style exposure they were 0.041?ng/ml serum, 0.060?ng/ml saliva, and 0.948?ng/mg creatinine in urine. Finally, we measured substantial differences in solution nicotine concentrations, pH, use behavior and consumption.Our data show that although exposures may vary considerably, nonusers can systemically absorb nicotine following acute exposure to secondhand e-cigarette aerosol. This can particularly affect sensitive subpopulations, such as children and women of reproductive age.  相似文献   
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BACKGROUND: Airway inflammation in cystic fibrosis (CF) is exaggerated and characterized by neutrophil-mediated tissue destruction, but its genesis and mechanisms remain poorly understood. To further define the pulmonary inflammatory response, we conducted a proteome-based screen of bronchoalveolar lavage fluid (BALF) collected from young children with and without CF experiencing endobronchial infection. METHODS: We collected BALF samples from 45 children younger than 5 years and grouped them according to the presence of respiratory pathogens: > or = 1 x 10(5) colony-forming units (CFU)/mL BALF (18 and 12 samples with and without CF, respectively) and <1 x 10(5) CFU/mL (23 and 15 samples). BALF proteins were analyzed with SELDI-TOF mass spectrometry (MS) and H4 ProteinChips. Proteins were identified and characterized using trypsin digestion, tandem MS, Fourier transform ion cyclotron resonance MS, immunoblotting, and ELISA. RESULTS: The SELDI-TOF MS BALF profiles contained 53 unique, reliably detected proteins. Peak intensities of 24 proteins differed significantly between the CF and non-CF samples. They included the neutrophil proteins, alpha-defensin 1 and 2, S100A8, S100A9, and S100A12, as well as novel forms of S100A8 and S100A12 with equivalent C-terminal deletions. Peak intensities of these neutrophil proteins and immunoreactive concentrations of selected examples were significantly higher in CF than non-CF samples. CONCLUSIONS: Small neutrophil-derived BALF proteins, including novel C-terminal truncated forms of S100A proteins, are easily detected with SELDI-TOF MS. Concentrations of these molecules are abnormally high in early CF lung disease. The data provide new insights into CF lung disease and identify novel proteins strongly associated with CF airway inflammation.  相似文献   
175.
Despite consistent support for Cole’s (1990, 1991) competency-based model of depression in children and adolescents, no studies have examined this model in adult samples and few have focused on congruence between domains of self-perceived competence and specific forms of negative life events. Addressing this gap in the current cross-sectional study, we found that forms of self-perceived competence may both moderate and partially mediate the link between negative events and young adults’ current depressive symptoms. Specifically, there was evidence for both the partial mediating and moderating roles of perceived global self-worth and self-perceived scholastic competence. In contrast, perceived social acceptance and negative social events appeared to be independent correlates of depressive symptoms.
Dorothy J. UhrlassEmail:
  相似文献   
176.
This randomized controlled trial assessed the efficacy of a five-session version of Skills Training in Affective and Interpersonal Regulation (STAIR) among veterans obtaining treatment in primary care. Veterans who screened positive for either posttraumatic stress disorder (PTSD) or depression (N = 26) were enrolled and randomized into either five-session STAIR or treatment as usual (TAU). Assessments of PTSD symptoms (PTSD Checklist for DSM-5; PCL-5), depression (Beck Depression Inventory–II; BDI-II), emotion regulation (Difficulties in Emotion Regulation Scale; DERS), and social engagement difficulties (World Health Organization Disability Assessment 2.0; WHODAS-2) were assessed at pretreatment, posttreatment, and 3-month follow-up assessments. Participants assigned to the five-session STAIR condition reported significant improvements on all measures, whereas those assigned to TAU showed no change. Group × Treatment interactions were significant for all outcomes, and effect sizes for the interactions ranged from moderate to large, Hedge's gs = 0.81 for the PCL-5, 1.15 for the BDI-II, 0.75 for the DERS, and 0.81 for the WHODAS-2. The results indicate that five-session STAIR, a brief, skills-focused treatment, may be effective in reducing a range of symptoms and in improving social functioning among veterans treated in primary care settings.  相似文献   
177.
We compared the effect of a sclerostin antibody to that of a clinically relevant dose of parathyroid hormone (PTH) in a rat model for metaphyseal bone healing. Screws of steel or poly methyl methacrylate (PMMA) were inserted bilaterally into the proximal tibia of young male rats. During 4 weeks the animals then received injections of either phosphate buffered saline (control), sclerostin antibody (25 mg/kg, twice weekly) or PTH (5 µg/kg, daily). The healing response around the screws was then assessed by mechanical testing and X‐ray microtomography (µCT). To distinguish between effects on healing and general effects on the skeleton, other untraumatized bone sites and serum biomarkers were also assessed. After 4 weeks of treatment, PTH yielded a 48% increase in screw pull‐out force compared to control (p = 0.03), while the antibody had no significant effect. In contrast, the antibody increased femoral cortical and vertebral strength where PTH had no significant effect. µCT showed only slight changes that were statistically significant for the antibody mainly at cortical sites. The results suggest that a relatively low dose of PTH stimulates metaphyseal repair (screw fixation) specifically, whereas the sclerostin antibody has wide‐spread effects, mainly on cortical bone, with less influence on metaphyseal healing. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:471–476, 2014.  相似文献   
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ObjectivesTreating high-risk prostate cancer (CaP) with definitive therapy improves survival. We evaluated whether having health insurance reduces racial disparities in the use of definitive therapy for high-risk CaP.Materials and methodsThe Surveillance, Epidemiology, and End Results Program was used to identify 70,006 men with localized high-risk CaP (prostate-specific antigen level >20 ng/ml or Gleason score 8–10 or stage>cT3a) diagnosed from 2007 to 2010. We used multivariable logistic regression to analyze the 64,277 patients with complete data to determine the factors associated with receipt of definitive therapy.ResultsCompared with white men, African American (AA) men were significantly less likely to receive definitive treatment (adjusted odds ratio [AOR] = 0.60; 95% CI: 0.56–0.64; P<0.001) after adjusting for sociodemographics and known CaP prognostic factors. There was a significant interaction between race and insurance status (Pinteraction = 0.01) such that insurance coverage was associated with a reduction in racial disparity between AA and white patients regarding receipt of definitive therapy. Specifically, the AOR for definitive treatment for AA vs. white was 0.38 (95% CI: 0.27–0.54, P<0.001) among uninsured men, whereas the AOR was 0.62 (95% CI: 0.57–0.66, P<0.001) among insured men.ConclusionsAA men with high-risk CaP were significantly less likely to receive potentially life-saving definitive treatment when compared with white men. Having health insurance was associated with a reduction in this racial treatment disparity, suggesting that expansion of health insurance coverage may help reduce racial disparities in the management of aggressive cancers.  相似文献   
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