Air-water exchange of anthropogenic and natural organohalogens on International Polar Year (IPY) expeditions in the Canadian Arctic.

Shipboard measurements of organohalogen compounds in air and surface seawater were conducted in the Canadian Arctic in 2007-2008. Study areas included the Labrador Sea, Hudson Bay, and the southern Beaufort Sea. High volume air samples were collected at deck level (6 m), while low volume samples were taken at 1 and 15 m above the water or ice surface. Water samples were taken within 7 m. Water concentration ranges (pg L(-1)) were as follows: α-hexachlorocyclohexane (α-HCH) 465-1013, γ-HCH 150-254, hexachlorobenzene (HCB) 4.0-6.4, 2,4-dibromoanisole (DBA) 8.5-38, and 2,4,6-tribromoanisole (TBA) 4.7-163. Air concentration ranges (pg m(-3)) were as follows: α-HCH 7.5-48, γ-HCH 2.1-7.7, HCB 48-71, DBA 4.8-25, and TBA 6.4 - 39. Fugacity gradients predicted net deposition of HCB in all areas, while exchange directions varied for the other chemicals by season and locations. Net evasion of α-HCH from Hudson Bay and the Beaufort Sea during open water conditions was shown by air concentrations that averaged 14% higher at 1 m than 15 m. No significant difference between the two heights was found over ice cover. The α-HCH in air over the Beaufort Sea was racemic in winter (mean enantiomer fraction, EF = 0.504 ± 0.008) and nonracemic in late spring-early summer (mean EF = 0.476 ± 0.010). This decrease in EF was accompanied by a rise in air concentrations due to volatilization of nonracemic α-HCH from surface water (EF = 0.457 ± 0.019). Fluxes of chemicals during the southern Beaufort Sea open water season (i.e., Leg 9) were estimated using the Whitman two-film model, where volatilization fluxes are positive and deposition fluxes are negative. The means ± SD (and ranges) of net fluxes (ng m(-2) d(-1)) were as follows: α-HCH 6.8 ± 3.2 (2.7-13), γ-HCH 0.76 ± 0.40 (0.26-1.4), HCB -9.6 ± 2.7 (-6.1 to -15), DBA 1.2 ± 0.69 (0.04-2.0), and TBA 0.46 ± 1.1 ng m(-2) d(-1) (-1.6 to 2.0).

Vernakalant hydrochloride: A novel atrial-selective agent for the cardioversion of recent-onset atrial fibrillation in the emergency department.

OBJECTIVES: Vernakalant is a relatively atrial-selective antiarrhythmic agent that has been shown to successfully convert atrial fibrillation (AF) to normal sinus rhythm for some patients whose onset of dysrhythmia occurred less than 7 days previously. This study sought to evaluate the efficacy and safety of vernakalant for patients with recent-onset AF. METHODS: This was a post hoc analysis of patients with recent-onset AF (> 3 to ≤ 48 hours) enrolled in the double-blind, placebo-controlled Atrial arrhythmia Conversion Trial (ACT) I and the open-label ACT IV trials. The studies enrolled adults presenting with AF to 78 emergency departments (ED) and cardiac clinics in six countries. Patients received a 10-minute intravenous infusion of vernakalant or placebo, followed by an additional infusion if necessary. Efficacy assessments included conversion to sinus rhythm within 90 minutes and median time to conversion. Safety evaluations included telemetry, Holter monitoring, and adverse events (AEs). RESULTS: Of the 290 patients, 229 received vernakalant, 61 received placebo, and the overall mean age was 59 years. The vernakalant and placebo groups were similar. Of all patients given vernakalant, 136 (59.4%) converted to sinus rhythm within 90 minutes, compared with three (4.9%) placebo patients. The median time to conversion with vernakalant was 12 minutes (interquartile range = 7-24.5 minutes). Clinically significant bradycardia and hypotension were uncommon, and no cases of torsade de pointes or ventricular fibrillation occurred. CONCLUSIONS: Vernakalant rapidly converted recent-onset AF to sinus rhythm in over half of patients, was well tolerated, and has the potential to offer an important therapeutic option for rhythm control of recent-onset AF in the ED.

Standardization and in vivo antioxidant activity of ethanol extracts of fruit and leaf of Piper sarmentosum.

The present study aimed to investigate standardized ethanol extracts of fruit and leaves of Piper sarmentosum for their in vivo antioxidant activity in rats using a CCl (4)-induced oxidative stress model. The standardization was based on the quantification of the markers pellitorine, sarmentine and sarmentosine by high performance liquid chromatography (HPLC), and determination of total primary and secondary metabolites. The rats, divided into 7 groups each (n = 6), were used as follows: group 1 (CCl (4), negative control), group 2 (untreated, control), groups 3 and 4 (fruit extract 250 and 500 mg/kg, respectively), groups 5 and 6 (leaf extract 250 and 500 mg/kg, respectively) and group 7 (vitamin-E 100 mg/kg, positive control). The doses were administered orally for 14 days; 4 h following the last dose, a single dose of CCl (4) (1.5 mg/kg) was given orally to all the groups except group 2, and after 24 h, blood and liver of each animal were obtained. Analysis of plasma and liver homogenate exhibited significant preservation of markers of antioxidant activity, total plasma antioxidant activity (TPAA), total protein (TP), superoxide dismutase (SOD), catalase (CAT), and thiobarbituric acid reactive species (TBARS), in the pretreated groups as compared to the CCl (4) group (p < 0.05). Histology of the liver also evidenced the protection of hepatocytes against CCl (4) metabolites in the pretreated groups. The results of this study indicate the IN VIVO antioxidant activity of both extracts of the plant, which may be valuable to combat diseases involving free radicals.

[Comparison on the quality of scolopendra commodities from different gathering periods].

Through physo-chemical analysis and pharmacological study to Scolopendra commodites, it showed that the quality of the commodities from autumn was better but gather, dry and store difficultly. According to market, gathering at Spring is available.