Hyperkalemia in a Hemolyzed Sample in Pediatric Patients: Repeat or Do Not Repeat?

OBJECTIVE: The aim of the study is to analyze whether repeat testing is necessary in healthy children presenting to a pediatric emergency department (ED) who are found to have hyperkalemia on a hemolyzed specimen. METHODS: A 5-year retrospective analysis of pediatric ED patients found to have elevated potassium values on laboratory testing of a sample reported to be hemolyzed. All patients aged 0 to 17 years who had an elevated potassium level after an intravenous draw resulted from a serum sample that was reported as hemolyzed during an ED visit were included in the study. RESULTS: One hundred eighty-seven patients with some degree of both hemolysis and hyperkalemia were included in the final analysis. The median age was 1.9 years of age. The most common race among all patients was White, followed by African American, and Asian. One hundred forty-five children had repeat sampling for hemolyzed hyperkalemia, 142 children, 97.9% (95% confidence interval, 95.6%-100%) had a normal potassium on repeat and 3 children, 2.1% (95% confidence interval, 0.0%-4.4%) had true hyperkalemia. The frequency of true hyperkalemia in our study population was 2% (3/145). All 3 of these patients had underlying conditions that would appropriately have raised clinician suspicion for hyperkalemia. CONCLUSIONS: It may be unnecessary to obtain repeat samples to confirm normal potassium in a hemolyzed sample with normal blood urea nitrogen and creatinine.

Incidental coronary calcium in cancer patients treated with anthracycline and/or trastuzumab.

AIMS: Cancer patients are at increased risk of cardiovascular disease (CVD) after treatment with potentially cardiotoxic treatments. Many cancer patients undergo non-gated chest computed tomography (NCCT) for cancer staging prior to treatment. We aimed to assess whether coronary artery calcification on NCCT predicts CVD risk in cancer patients. METHODS AND RESULTS: Six hundred and three patients (mean age: 61.3 years, 30.8% male) with either breast cancer, lymphoma, or sarcoma were identified retrospectively. Primary endpoint was a major adverse cardiac event (MACE) composite including non-fatal myocardial infarction, new heart failure (HF) diagnosis, HF hospitalization, and cardiac death, with Fine-Gray analysis for non-cardiac death as competing risk. Secondary endpoints included a coronary composite and a HF composite. Coronary artery calcification was present in 194 (32.2%) and clinically reported in 85 (43.8%) patients. At a median follow-up of 5.3 years, 256 (42.5%) patients died of non-cardiac causes. Coronary artery calcification presence or extent was not an independent predictor of MACE [sub-distribution hazards ratio (SHR) 1.28; 0.73-2.27]. Coronary artery calcification extent was a significant predictor of the coronary composite outcome (SHR per two-fold increase 1.14; 1.01-1.28), but not of the HF composite outcome (SHR per two-fold increase 1.04; 0.95-1.14). CONCLUSION: Coronary artery calcification detected incidentally on NCCT scans in cancer patients is prevalent and often not reported. Coronary artery calcification presence or extent did not independently predict MACE. Coronary artery calcification extent was independently associated with increased risk of CAD events but not HF events.

High-Resolution Linkage Map and QTL Analyses of Fruit Firmness in Autotetraploid Blueberry.

Blueberry (Vaccinium corymbosum and hybrids) is an autotetraploid crop whose commercial relevance has been growing steadily during the last 20 years. However, the ever-increasing cost of labor for hand-picking blueberry is one main constraint in competitive marketing of the fruit. Machine harvestability is, therefore, a key trait for the blueberry industry. Understanding the genetic architecture of traits related to machine harvestability through Quantitative Trait Loci (QTL) mapping is the first step toward implementation of molecular breeding for faster genetic gains. Despite recent advances in software development for autotetraploid genetic mapping, a high-resolution map is still not available for blueberry. In this study, we crafted a map for autotetraploid low-chill highbush blueberry containing 11,292 SNP markers and a total size of 1,953.97 cM (average density of 5.78 markers/cM). This map was subsequently used to perform QTL analyses in 2-year field trials for a trait crucial to machine harvesting: fruit firmness. Preliminary insights were also sought for single evaluations of firmness retention after cold storage, and fruit detachment force traits. Significant QTL peaks were identified for all the traits and overlapping QTL intervals were detected for firmness across the years. We found low-to-moderate QTL effects explaining the phenotypic variance, which suggest a quantitative nature of these traits. The QTL intervals were further speculated for putative gene repertoire. Altogether, our findings provide the basis for future fine-mapping and molecular breeding efforts for machine harvesting in blueberry.

Advancements in Low-Chill Blueberry Vaccinium corymbosum L. Tissue Culture Practices.

The demand for blueberry Vaccinium corymbosum L. (and hybrids) plants has significantly increased in the last 30 years due to its market expansion. In vitro propagation of sterile plants are required for commercial purposes but also for research applications such as plant transformation. Thus far, tissue culture characteristics of the tropical-adapted blueberry have been scarcely studied. In this study we present the following findings: (i) zeatin, a hormone used to promote plant growth, should be used in the 1-2 mg/L range to promote plant architecture optimal for transformation experiments; (ii) red-blue LED lights induce more production of meristems and biomass than white LED or fluorescent lights; (iii) levels as high as 1000 mg/L of decontamination agents (the antibiotics timentin and cefotaxime) can be used to eliminate Agrobacterium overgrowth without inhibiting plant growth during plant transformation experiments; (iv) kanamycin, paromomycin, and geneticin, which are widely used antibiotics to select transgene-carrying transformants, cannot be efficiently used in this system; (v) glufosinate, a widely used herbicide, shows potential to be used as an effective selectable marker for transformed plants.

Hepatic gene expression response to acute indomethacin exposure.

BACKGROUND: Rising morbidity and mortality related to the use of NSAIDs has led to the withdrawal of some of these agents and reconsideration of the adverse effects and usage paradigms of commonly available NSAIDs. Our objective in this study was to assay molecular indicators of acute hepatic injury associated with the administration of indomethacin, a prototypical NSAID, metabolized by the liver that undergoes enterohepatic circulation with associated gastrointestinal adverse effects. METHODS: Analysis of gene expression, using high-throughput, ADME (absorption, distribution, metabolism, excretion)-specific microarrays, was performed on RNA extracted from the livers of control or indomethacin treated rats, in parallel with serum enzyme tests and histological analysis of paraffin-embedded liver specimens. Male Sprague-Dawley rats (n = 45) were administered intraperitoneal injections of indomethacin for 3 days at the recommended normal dose (6.7 mg/kg), indomethacin at a high dose (20 mg/kg) or vehicle alone (controls). RESULTS: Upon termination of the study on day 4, serum gamma-glutamyl transferase activity and alkaline phosphatase/alanine aminotransferase ratios were significantly elevated in both high- and normal-dose cohorts compared with vehicle-treated animals. Diffuse microvascular steatosis was present in hepatic serial sections obtained from all animals subjected to the high-dosage regimen. High-resolution microarray analysis (six replicates/gene/animal) identified 256 genes, after outlier removal, in 17 functional classifications that were significantly altered by the high, but not by the normal dosage. These included depression of 10 of 11 cytochrome P450 genes (2B3, 2C70, 1A2-P2, 4F1, 2E1, 3A1, 2F1, 3AP7, 2C11, phenobarb-inducible P6) and 7 of 9 genes involved in the response to reactive oxygen species (e.g. glutathione reductase, glutathione transferase, and superoxide dismutase). Of 16 genes associated with toxin removal, nine exhibited significantly decreased transcripts. There was a marked shift away from lipid metabolism (decreased expression of eight genes) towards glucose utilization associated with steatosis. Despite the compromise of detoxification programs and a shift in metabolic substrate utilization, a compensatory remodeling response was activated, including genes for metalloproteases (ADAM10, MMP10, MMP11), integrins (integrin alpha-1 and alpha-E1), and extracellular matrix molecules (platelet/endothelial cell adhesion molecule-1 and heparan sulfate proteoglycan, perlecan), as well as transcripts associated with cell proliferation. The expression levels of only five genes were significantly altered among animals receiving the normal indomethacin dosage. CONCLUSION: These data confirmed that even brief exposure to indomethacin altered serum enzymatic activities and that high levels significantly altered gene expression in the liver and hepatic histology (by interfering with the clearance of toxins and xenobiotic substrates) and the regulation of basal metabolism.