Interleukin-6 and E-selectin in acute coronary syndromes and stable angina pectoris. A comparative study.

OBJECTIVES: The purpose of the study was to compare the serum levels of interleukin-6 (IL-6), E-selectin, and trans-fatty acids (TFA) between those with stable and unstable angina pectoris. METHODS: From September 2008 to March 2009, a case-control study was performed at two university hospitals. We included 89 patients with acute coronary syndrome (ACS) including patients with myocardial infarction and those with unstable angina pectoris (case group) and 93 patients with stable angina pectoris (control group). The two groups were matched with respect to demographic characteristics and risk factors of cardiovascular diseases. Serum levels of IL-6 and E-selectin were measured using the enzyme linked immunosorbent assay, while TFA and lipoproteins were measured using gas chromatography and enzymatic methods, respectively. RESULTS: No significant differences between baseline characteristics of the two study groups were observed. Patients with stable angina had significantly higher serum levels of total cholesterol (187.0 ± 3.7 vs. 171.6 ± 4.2 mg/dl; p = 0.009), low density lipoproteins (104.8 ± 2.4 vs. 95.4 ± 2.7; p = 0.017), and TFA (1.41 ± 0.47 vs. 1.24 ± 0.69 mg/dl; p = 0.047) compared to those with ACS. Serum levels of IL-6 were found to be significantly higher in those with stable angina compared to those with ACS (102.4 ± 1.9 vs. 224.6 ± 3.6; p = 0.007). However, patients with ACS had higher levels of E-selectin (53.5 ± 25.7 vs. 49.2 ± 23.5 µg/dl; p = 0.52), but the difference did not reach statistical significance. CONCLUSION: In the current study, inflammation as measured by IL-6 and E-selectin was not found to play an important role in progression of ischemic heart disease from stable angina to unstable angina or myocardial infarction, which is contrary to previous studies.

Increasing contaminant burdens in an arctic fish, Burbot ( Lota lota ), in a warming climate.

The temporal patterns of mercury (Hg), polychlorinated biphenyls (PCBs), and other contaminants in Arctic aquatic biota are usually attributed to changing atmospheric sources. However, climate variability and change is another means of altering contaminant fate and bioavailability. We show here that the concentrations of Hg and PCBs in Mackenzie River burbot ( Lota lota ), a top predator fish and important staple food for northern Canadian communities, have increased significantly over the last 25 years despite falling or stable atmospheric concentrations, suggesting that environmental processes subsequent to atmospheric transport are responsible. Using a dated sediment core from a tributary lake near the Mackenzie River sampling site, we show that variations in Hg concentrations downcore are strongly associated with labile, algal-derived organic matter (OM). Strong temporal correlations between increasing primary productivity and biotic Hg and PCBs as reflected by burbot suggest that warming temperatures and reduced ice cover may lead to increased exposure to these contaminants in high trophic level Arctic freshwater biota.

Historical interrelated variations of mercury and aquatic organic matter in lake sediment cores from a subArctic lake in Yukon, Canada: further evidence toward the algal-mercury scavenging hypothesis.

This study investigates the role of climate-driven aquatic productivity increases in conrolling the sedimentary accumulation of mercury (Hg) in Kusawa Lake, Yukon, Canada. Organic geochemistry data reveals a significant link between the increasing trends of Hg and of labile algal-derived organic matter (OM) over the centuries and in particular over recent decades. Sedimentary Hg accumulation rates continue to increase even though atmospheric concentrations of Hg have remained the same or even declined. Together, these findings indicate that the significant rise in Hg content recorded in the sediments since the early 1950s may not be representative of increasing atmospheric Hg levels but are strongly influenced by elevated concentrations of algal-derived OM in the water-column. These likely increase the scavenging rate of "available" Hg from the water column. Therefore, recent increases in algal productivity may result in overestimation of the historical rates of atmospheric Hg deposition recorded in the sediments. This study confirms earlier published findings from two High Arctic lakes, and shows that the Hg-OM scavenging hypothesis may also apply to sub-Arctic lakes.

Monitoring the distribution and deposition of trace elements associated with a zinc-lead smelter in the Trail area, British Columbia, Canada.

The atmospheric deposition and regional dispersion pattern of the elements As, Cd, Cu, Hg, Pb and Zn, emitted from Pb-Zn smelters at Trail, British Columbia, Canada, were studied for a period of two years using the passive collection moss-monitoring method. Concentrations of these elements in moss bags, exposed to atmospheric deposition for three months, were first corrected for geogenic input and then site-specific local background level to produce common background elemental concentrations for all monitoring stations. The results of this study indicate that the deposition of these elements is greatest in proximity to the smelter and decreases with an increase in distance. The regional dispersion pattern generally varies seasonally, with the magnitude of variation being dependent on the element under study and the location of the monitoring station. Overall, the deposition of these elements (as registered by moss-monitoring stations) appears to be a complex phenomenon involving various factors such as meteorological conditions (prevailing wind direction and precipitation), physiography (topography, valley shape and orientation) and in-process activities at the smelters (production level, emission control efficiency and the geochemistry of feed). However, the results of this study indicate that, on an annual basis, in-process activities, particularly production levels of Pb and Zn and the quantity of emissions from the stack, are more directly related to the observed deposition of the elements than any of the other factors.

Historical variation of elements with respect to different geochemical fractions in recent sediments from Pigeon Lake, Alberta, Canada.

Geochemical analysis of elements and organic matter were conducted on vertical profiles of the recent sediments from Pigeon Lake, Alberta, Canada, to determine historical variations in elemental content of the sediments as related to their geochemical fractions. The elements are grouped according to their affinity with different geochemical fractions, by using cluster analysis and sequential extraction experiments. As a result, four elemental fractions were identified: clastic mineral detritus; carbonate; organic; and elements that show less similarity to the previous groups perhaps due to anthropogenic input or the influence of other fractions, such as oxyhydroxides. Following the identification of geochemical fractions in the sediments, a three-step normalizing method was applied using parameters that represent each geochemical fraction. These normalizing techniques appear to be important in verifying whether the variation of elements is indeed the result of anthropogenic and/or natural activities. The normalized data are correlated with the recent history of human activity and natural events near Pigeon Lake. Given the age of the lake sediments, this correlation indicates that the depth profiles of elements after being normalized to the organic and carbonate fractions reflect the variation of detrital input into the lake. However, the former mainly corresponds to the coarse-grained clastic minerals originating from high-energy erosion as the result of natural events (e.g., flooding), whereas the latter corresponds to the low-energy erosion of the fine particles (enriched in lithophile elements) due to deforestation in the drainage basin. Normalizing to the clastic mineral detritus fraction results in the increase of heavy metals in the uppermost part of the sediment profiles, which coincides with industrial activities during the past two decades in central Alberta. However, the concentration of these elements is negligible, as compared to the quantities released by geogenic processes (erosion).