Hypertensive emergencies: guidelines and best-practice recommendations.

Due to a variety of demographic and public health factors, the number of emergency department visits related to hypertensive emergencies has increased dramatically in recent decades, making it imperative that clinicians clearly understand the current treatment guidelines and definitions for the spectrum of hypertensive disease. This issue reviews current evidence on identifying and managing hypertensive emergencies and the differences between expert opinions on diagnosing and managing these emergencies. Clear protocols differentiating patients with hypertension from patients with hypertensive emergencies are needed to appropriately manage this patient population.

A Randomized Trial on the Efficacy of Topical Anesthesia for Pain Reduction during Frame Placement for Gamma Knife Radiosurgery.

BACKGROUND/AIMS: Frame application for gamma knife radiosurgery (GKR) may be perceived as painful by patients. This study was designed to assess the efficacy of EMLA (2.5% lidocaine/2.5% prilocaine) in pain reduction. METHODS: This was a prospective, randomized, and controlled trial approved by our institutional review board. Fifty-four patients undergoing outpatient GKR were divided into EMLA and placebo groups. Prior to frame placement, EMLA/placebo was applied to the patient's forehead. A visual analog scale (VAS) was used to measure pain during 4 intervals: frontal injections, occipital injections, frontal screw insertion, and overall discomfort. This study was designed to observe a difference of 1.0 on the VAS at a power of 95%. RESULTS: VAS for EMLA versus placebo for frontal injections (5.2 ± 2.7 vs. 5.7 ± 2.0, respectively; p < 0.45), back injections, (6.5 ± 2.2 vs. 5.9 ± 2.3, respectively; p < 0.30), frontal pins (4.6 ± 2.7 vs. 4.6 ± 2.2, respectively; p < 0.99), and overall discomfort (p < 0.29) were not significantly different. A comparison between back and frontal injections for EMLA (6.54 vs. 5.19, respectively; p < 0.16) and placebo (5.89 vs. 5.68, respectively; p < 0.69) showed no significant difference between group and location (p < 0.21). CONCLUSION: Application of EMLA did not significantly reduce pain when used preoperatively for frame fixation. EMLA is no longer used as part of our routine for patients undergoing GKR.

Impact of ozonation on naphthenic acids speciation and toxicity of oil sands process-affected water to Vibrio fischeri and mammalian immune system.

Oil sands process-affected water (OSPW) is the water contained in tailings impoundment structures in oil sands operations. There are concerns about the environmental impacts of the release of OSPW because of its toxicity. In this study, ozonation followed by biodegradation was used to remediate OSPW. The impacts of the ozone process evolution on the naphthenic acids (NAs) speciation and acute toxicity were evaluated. Ion-mobility spectrometry (IMS) was used to preliminarily separate isomeric and homologous species. The results showed limited effects of the ozone reactor size on the treatment performance in terms of contaminant removal. In terms of NAs speciation, high reactivity of NAs with higher number of carbons and rings was only observed in a region of high reactivity (i.e., utilized ozone dose lower than 50 mg/L). It was also found that nearly 0.5 mg/L total NAs was oxidized per mg/L of utilized ozone dose, at utilized ozone doses lower than 50 mg/L. IMS showed that ozonation was able to degrade NAs, oxidized NAs, and sulfur/nitrogenated NAs. Complete removal of toxicity toward Vibrio fischeri was achieved after ozonation followed by 28-day biodegradation period. In vitro and in vivo assays indicated that ozonation reduced the OSPW toxicity to mice.

Commercial naphthenic acids and the organic fraction of oil sands process water induce different effects on pro-inflammatory gene expression and macrophage phagocytosis in mice.

Naphthenic acids (NAs) are believed to be the major toxic component of oil sands process water (OSPW). Different OSPW preparations have distinct NA compositions, and additional organics, that differ from the commercial NAs (C-NAs) often used for toxicology studies. To evaluate whether C-NAs are an adequate model to study OSPW toxicity in complex organisms, we compared the effects of C-NAs and the extractable organic fraction of OSPW (OSPW-OF) on mice immune mechanisms. Mice were orally exposed to different C-NA doses, or OSPW-OF at the same NA dose, for up to 8 weeks, and the expression of pro-inflammatory genes in different organs was determined using quantitative PCR. C-NAs and OSPW-OF altered the expression of pro-inflammatory genes, inducing either expression down-regulation or up-regulation, depending on the organ examined and time after exposure. The time at which gene expression alterations occurred, and the specific sets of genes whose expression was altered, were very different between animals exposed to C-NAs or to OSPW-OF. We evaluated the ability of mouse peritoneal macrophages to phagocytose yeast cell wall, as a measure of the ability of mice to mount a central function of the innate immune response. Phagocytosis was significantly reduced in animals exposed to C-NAs, but enhanced in mice exposed to OSPW-OF. Our results indicate that studies using C-NAs may not necessarily reflect the possible effects induced in animals by process water from tailing ponds.

Commercial naphthenic acids and the organic fraction of oil sands process water downregulate pro-inflammatory gene expression and macrophage antimicrobial responses.

This is the first report showing that the organic fraction of oil sands process water (OSPW-OF), and commercial naphthenic acids (C-NAs), cause immunotoxicity. The exposure of mouse bone marrow-derived macrophages (BMDM) to different amounts of C-NAs or OSPW-OF, did not affect cell viability in vitro. We examined whether exposure of BMDM to C-NAs or OSPW-OF affected various antimicrobial responses of these cells. A dose-dependent decrease in nitric oxide response was observed after treatment of BMDM with OSPW-OF, but not with C-NAs. Although OSPW-OF and C-NAs both down-regulated the respiratory burst response of BMDM, the suppression of the production of reactive oxygen intermediates was more pronounced in cells treated with OSPW-OF. Treatment with OSPW-OF or C-NAs reduced BMDM phagocytosis of zymosan and latex beads. The decrease of BMDM antimicrobial response after exposure to OSPW-OF or C-NAs, was accompanied by decreased pro-inflammatory cytokine gene expression. Oral exposure of mice to OSPW-OF caused down-regulation in the expression of genes encoding pro-inflammatory cytokines IFNγ, IL-1ß and CSF-1. Our findings indicated that OSPW causes immunotoxic effects that may impair the ability of an exposed host to defend against infectious disease. Furthermore, given the differences between the effects of OSPW-OF and C-NAs, C-NAs should not be assumed to be a direct surrogate for the immunotoxic chemical species in OSPW.