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81.
BACKGROUND: The prognostic value of cardiac troponins (cTn) in patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) and chronic kidney disease (CKD) is debated. HYPOTHESIS: We tested the performance of cTnI and cTnT for risk stratification in patients with CKD and evaluated the prognostic significance of cTnI and cTnT elevations by their magnitude across the range of CKD severity. METHODS: We examined correlations among cTn elevation, CKD, and in-hospital mortality in 31,586 high-risk patients with NSTE ACS included in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines initiative (CRUSADE). Cardiac tropinins I and T levels were categorized as ratios of each site's upper limit of normal (ULN) for myocardial necrosis: normal (cTn ratio < or =1 x ULN), mild (cTn ratio > 1-3 x ULN), and major (cTn ratio > 3 x ULN) elevation. Estimated glomerular filtration rate (eGFR) was calculated using the abbreviated Modification of Diet in Renal Disease equation. Stages of CKD were categorized as normal to mild (eGFR > 60 mL/min), moderate (eGFR 30-60 mL/min), or severe (eGFR < 30 mL/min). RESULTS: Mortality increased more steeply across CKD stages (2.0%-12.9%) than across cTn ratio categories (2.7%-5.4%). In normal or mild CKD, mortality was low regardless of cTn elevations. In moderate CKD, mortality increased incrementally with cTnI (3.3% versus 5.4% versus 7.4%) and cTnT (3.7% versus 5.3% versus 7.3%) elevation. Among severe CKD patients, only major cTn elevations further distinguished risk (cTnI: 10.1% versus 9.7% versus 14.6%; cTnT: 7.0% versus 5.7% versus 14.0%). CONCLUSIONS: In patients with CKD, cTnI and cTnT perform equally in differentiating short-term prognosis following NSTE ACS; however, the prognostic impact of cTn is dependent upon the degree of CKD severity.  相似文献   
82.
BACKGROUND & AIMS: Esophagogastroduodenoscopy (EGD) is the current standard for evaluating esophageal varices, yet there is no universally accepted system of grading varices endoscopically and several studies have shown interobserver variability of endoscopic grading. High-resolution endoluminal ultrasound 20 MHz (HRES) has been shown to detect varices accurately and can be performed without sedation. Our aim was to compare the detection of esophageal varices by transnasal HRES and EGD. METHODS: We prospectively studied 37 cirrhotic patients being evaluated for esophageal varices. HRES was used to measure the largest esophageal variceal diameter and then EGD was performed. Photographs were taken for both procedures. Three blinded investigators graded the EGD photographs at 2 periods. End points were as follows: (1) the correlation of HRES variceal diameter and EGD grading of varices, and (2) the assessment of interobserver and intraobserver variation in varix grading by EGD. RESULTS: The correlation between the transnasal HRES and EGD was .63, with a 95% confidence interval of .37-.80. The HRES detected early varices that were not seen by EGD. The interobserver correlation for EGD scoring was .87 or greater in all comparisons and the intraobserver correlation was .91 or greater. CONCLUSIONS: In conclusion, there is a significant correlation between transnasal HRES size measurement of esophageal varices and EGD. HRES is much more sensitive in detecting early esophageal varices and may not require sedation, suggesting that it may be more tolerable to patients and is worth further study.  相似文献   
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Digestive Diseases and Sciences - Acute kidney injury is seen in approximately 30% of patients with severe alcohol-associated hepatitis (AH) and is associated with increased mortality. Controversy...  相似文献   
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Molecular genetic studies on vascular tumors are rare. Recently, possible involvement of MYC and KDR has been documented in a subset of angiosarcomas of soft tissue. We performed a cytogenetic analysis of primary angiosarcomas of bone (n = 13) and soft tissue (n = 5) using high density array‐comparative genomic hybridization (array‐CGH). Regions of interest were validated by fluorescence in situ hybridization (FISH). Antibodies for candidate genes (SKI, MYC, KDR, and MAPK9) were selected and immunohistochemistry was performed. Six angiosarcomas of bone and four angiosarcomas of soft tissue showed chromosomal losses, gains, and high level amplifications. Cluster analysis identified two groups: a group with a complex genetic profile and a group with only few genetic aberrations. Five regions of interest were selected, which were located at chromosome bands 1p36.23, 2q32‐34, 5q35, 8q24, and 17q21.32‐24.2. Interphase FISH confirmed the high‐level amplifications. Immunohistochemical analysis showed high expression of MYC (16/60), MAPK9 (63/69), and SKI (52/62). There were no differences between the two groups with regards to location, immunohistochemical expression nor survival. In summary, we identified two subgroups of angiosarcoma: those with few or no gross aberrations and those which show numerous genetic aberrations consisting of chromosomal losses, gains and high level amplifications or complex aberrations. The most common finding was amplification of 2q and 17q in both angiosarcoma of bone and soft tissue, suggesting overlap in tumorigenesis irrespective of their location. We show MYC amplification in primary angiosarcoma indicating this is not entirely specific for radiation‐induced angiosarcoma. © 2014 Wiley Periodicals, Inc.  相似文献   
87.
Background: Inorganic arsenic is one of the most common naturally occurring contaminants found in the environment. Arsenic is associated with a number of health outcomes, with epigenetic modification suggested as a potential mechanism of toxicity.Objective: Among a sample of 400 adult participants, we evaluated the association between arsenic exposure, as measured by blood and urinary total arsenic concentrations, and epigenome-wide white blood cell DNA methylation.Methods: We used linear regression models to examine the associations between arsenic exposure and methylation at each CpG site, adjusted for sex, age, and batch. Differentially methylated loci were subsequently examined in relation to corresponding gene expression for functional evidence of gene regulation.Results: In adjusted analyses, we observed four differentially methylated CpG sites with urinary total arsenic concentration and three differentially methylated CpG sites with blood arsenic concentration, based on the Bonferroni-corrected significance threshold of p < 1 × 10–7. Methylation of PLA2G2C (probe cg04605617) was the most significantly associated locus in relation to both urinary (p = 3.40 × 10–11) and blood arsenic concentrations (p = 1.48 × 10–11). Three additional novel methylation loci—SQSTM1 (cg01225779), SLC4A4 (cg06121226), and IGH (cg13651690)—were also significantly associated with arsenic exposure. Further, there was evidence of methylation-related gene regulation based on gene expression for a subset of differentially methylated loci.Conclusions: We observed significant associations between arsenic exposure and gene-specific differential white blood cell DNA methylation, suggesting that epigenetic modifications may be an important pathway underlying arsenic toxicity. The specific differentially methylated loci identified may inform potential pathways for future interventions.Citation: Argos M, Chen L, Jasmine F, Tong L, Pierce BL, Roy S, Paul-Brutus R, Gamble MV, Harper KN, Parvez F, Rahman M, Rakibuz-Zaman M, Slavkovich V, Baron JA, Graziano JH, Kibriya MG, Ahsan H. 2015. Gene-specific differential DNA methylation and chronic arsenic exposure in an epigenome-wide association study of adults in Bangladesh. Environ Health Perspect 123:64–71; http://dx.doi.org/10.1289/ehp.1307884  相似文献   
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89.

Background

Pain management guidelines in the emergency department (ED) may reduce time to analgesia administration (TTA). Intranasal fentanyl (INF) is a safe and effective alternative to intravenous opiates. The effect of an ED pain management guideline providing standing orders for nurse-initiated administration of intranasal fentanyl (INF) is not known. The objective of this study was to determine the impact of a pediatric ED triage-based pain protocol utilizing intranasal fentanyl (INF) on time to analgesia administration (TTA) and patient and parent satisfaction.

Methods

This was a prospective study of patients 3–17?years with an isolated orthopedic injury presenting to a pediatric ED before and after instituting a triage-based pain guideline allowing for administration of INF by triage nurses. Our primary outcome was median TTA and secondary outcomes included the proportion of patients who received INF for pain, had unnecessary IV placement, and patient and parent satisfaction.

Results

We enrolled 132 patients; 72 pre-guideline, 60 post-guideline. Demographics were similar between groups. Median TTA was not different between groups (34.5?min vs. 33?min, p?=?.7). Utilization of INF increased from 41% pre-guideline to 60% post-guideline (p?=?.01) and unnecessary IV placement decreased from 24% to 0% (p?=?.002). Patients and parents preferred the IN route for analgesia administration.

Conclusion

A triage-based pain protocol utilizing INF did not reduce TTA, but did result in increased INF use, decreased unnecessary IV placement, and was preferred by patients and parents to IV medication. INF is a viable analgesia alternative for children with isolated extremity injuries.  相似文献   
90.

Background

Botulism is a paralytic disease caused by the neurotoxin produced by Clostridium botulinum. The majority of cases are due to ingestion or injection drug use. Wound botulism from traumatic injury is exceedingly rare, with only one to two cases reported each year in the United States.

Case Report

A 27-year-old man presented to the Emergency Department with diplopia, dysphagia, and progressive weakness 10 days after sustaining a gunshot wound to his right lower leg. He had been evaluated for the same complaints at a different facility the day prior and was discharged. His wound appeared well-healing, but a high suspicion for wound botulism led to rapid consultation with the state Poison Control Center and the Centers for Disease Control and Prevention. The patient developed worsening respiratory insufficiency and required mechanical ventilation. Expeditious treatment with equine heptavalent botulinum antitoxin resulted in significant recovery of strength in 4 days. Serum toxin bioassay tested positive for botulinum neurotoxin type A.

Why Should an Emergency Physician be Aware of This?

Wound botulism now accounts for the majority of adult botulism in the United States. It should be considered in any patient with signs of neuromuscular disease and a recent injury, even if the wound appears uninfected.  相似文献   
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