Cytogenetic Damage in Shallot (<Emphasis Type="Italic">Allium cepa</Emphasis>) Root Meristems Induced by Oil Industry “High-Density Brines”

Saturated water solutions of calcium chloride, calcium bromide (densities 1.30 kg dm⁻³ and 1.61 kg dm⁻³, respectively) and their 1:1 mixture have been commonly used as oil industry “high-density brines.” In our experiment they were added to tap water in amounts appropriate to achieve concentrations of 0.025, 0.05, 0.075, and 0.1 mol dm⁻³ to study their cytotoxic effect on the root tip cells of shallot (Allium cepa L. var. ascalonicum). All tested solutions in concentrations of 0.075 and 0.1 mol dm⁻³ caused significant inhibition of shallot root growth. CaBr₂ showed this effect in concentration 0.05 mol dm⁻³. The investigated solutions in all concentrations applied decreased mitotic activity in root tip cells. The most of mitotic abnormalities were the consequence of spindle failure and chromosome stickiness. Furthermore, the cell microtubules were investigated by indirect immunofluorescence to confirm that most abnormalities observed were the consequence of spindle failure. The present study, as well as previously done Lemna tests and Chlorella tests showed that investigated samples have certain effects on plants, so constant control of their presence in the environment is needed. Received: 3 November 2001/Accepted: 5 April 2002     

Determination of benzene in urine by static headspace gas chromatography

This paper describes the application of static headspace gas chromatography in determining benzene in urine. The method was analytically validated for sensitivity (DL = 42 ng/l), repeatability (RSD = 3% and 4%), and accuracy (71%), and was applied in measuring urine benzene in nonsmokers (N = 14) and smokers (N = 18). All urine samples had measurable benzene concentrations. The method proved sensitive enough to establish a significant statistical difference (P < 0.000614) in urine benzene concentrations between smokers (mean = 760; range = 181-1869 ng/l) and nonsmokers (mean = 214; range = 61-515 ng/l).     

Workplace stressors and lifestyle-related cancer risk factors among female physicians: assessment using the Occupational Stress Index

This study examined the relationship between work stressors and lifestyle-related cancer risk factors (LRCRF): smoking, obesity, sedentariness and alcohol consumption, among 112 female physicians in Novi Sad, a region of high LRCRF prevalence. The participation rate was 92.6%. Participants completed the physician-specific version of the Occupational Stress Index (OSI). Self-reported data concerning LRCRF and working conditions were cross-validated with medical records, as well as with worksite measurements and expert observations. A total of 35 (31.3%) of the physicians were current smokers and 10 (8.9%) were heavy smokers (>20 cigarettes/day); 23 (20.5%) had a body mass index (BMI) of 28 or more, and 11 (9.8%) were obese (BMI> or =30). Only 27 (24.1%) regularly engaged in recreational physical activity (PA). Slightly over 5% consumed alcohol daily. Altogether 15 (13.4%) had a low lifestyle-related cancer risk profile (not a current smoker, BMI<28, regular recreational PA and no daily alcohol consumption). Total OSI and several OSI aspects, particularly threat avoidance alone or in combination, showed significant multivariate associations with LRCRF, as did individual OSI elements. The latter included long work hours, restricted problem-solving strategy, insufficient help with clinical difficulties and supervisory responsibility (obesity and/or sedentariness) and problems hampering patient care (smoking). There is an urgent need to lower the LRCRF among female physicians in this high risk region. Our findings suggest that diminishing the work stressor burden should be considered when developing intervention strategies aimed at these risk factors.     

Genome analysis linking recent European and African influenza (H5N1) viruses

To better understand the ecology and epidemiology of the highly pathogenic avian influenza virus in its transcontinental spread, we sequenced and analyzed the complete genomes of 36 recent influenza A (H5N1) viruses collected from birds in Europe, northern Africa, and southeastern Asia. These sequences, among the first complete genomes of influenza (H5N1) viruses outside Asia, clearly depict the lineages now infecting wild and domestic birds in Europe and Africa and show the relationships among these isolates and other strains affecting both birds and humans. The isolates fall into 3 distinct lineages, 1 of which contains all known non-Asian isolates. This new Euro-African lineage, which was the cause of several recent (2006) fatal human infections in Egypt and Iraq, has been introduced at least 3 times into the European-African region and has split into 3 distinct, independently evolving sublineages. One isolate provides evidence that 2 of these sublineages have recently reassorted.     

Glucocorticoid-induced osteoporosis

Glucocorticoids are the most common cause of drug-induced osteoporosis. Given the widespread use of oral glucocorticoids in the treatment of autoimmune, pulmonary, gastrointestinal disorders and organ transplantation, attention to glucocorticoid-induced osteoporosis has substantially increased. Bone loss occurs rapidly in the first few months of glucocorticoid therapy. Trabecular bone is affected more than cortical bone. Glucocorticoid treatment is associated with a substantially increased risk of fractures, particularly hip and vertebral fractures. The skeletal effects of glucocorticoids are both dose- and duration-dependent. The patophysiology of glucocorticoid-induced osteoporosis is a complex process, several mechanisms are proposed but not yet fully highlighted. Despite several evidence-based guidelines for the prevention and treatment of glucocorticoid-induced osteoporosis and the availability of effective therapeutic options, the proportion of individuals with appropriate evaluation and treatment remains relatively low.     

Seasonality of 214Bi activity in the human body and of 222Rn concentration in home ambient air

We studied the seasonal variation of the environmental radon progeny (214)Bi activity in the whole bodies (WB) of women and men participating in community-based studies at the Grand Forks Human Nutrition Research Center (GFHNRC), the (214)Bi background activity of the GFHNRC whole body counter (WBC) steel room, and ambient air (222)Rn concentration in the homes of Grand Forks residents, over the 1988-2004 time period. In this cross-sectional epidemiological study, (214)Bi activity in women and men, in the WBC steel room, and (222)Rn concentration in resident homes fluctuated such that the highest values were observed in winter and the lowest in summer, respectively. (214)Bi activity in the WB of human subjects was higher in women who have more (214)Bi activity per unit mass than men. Apart from their common seasonal pattern, human WB (214)Bi activity (lnBq) was comparatively higher than that for the ambient air (222)Rn activity in a human-equivalent volume of 72 L.     

Effect of Wine Polyphenol Resveratrol on the Contractions Elicited Electrically or by Norepinephrine in the Rat Portal Vein

We investigated the effects of resveratrol on rat portal vein (RPV) contractility without endothelium. Contractions were produced by electrical field stimulation of perivascular nerves (EFS), norepinephrine (NE), adenosine 5′‐triphosphate (ATP), high K⁺ solution and by calcium chloride (CaCl₂) in Ca²⁺‐free and high K⁺, Ca²⁺‐free solution. The EFS‐evoked contractions were more sensitive to resveratrol and to NS1619‐selective openers of big calcium‐sensitive (BK_Ca) channels, than NE‐evoked contractions. Effects of resveratrol on the ATP‐evoked contractions were weak. Blockers of BK_Ca channels partly inhibited the effect of resveratrol only in EFS‐contracted preparations. Western blotting showed that RPV expressed K_Ca1.1 protein. Inhibitors of ATP‐ and voltage‐sensitive K⁺ channels did not modify the effects of resveratrol. None of the antagonists of K⁺ channels affected the resveratrol inhibition of NE‐evoked contractions and effect of high concentrations of resveratrol on the EFS‐evoked contractions. Resveratrol more potently inhibited CaCl₂ than potassium chloride contractions of RPV. Thus, BK_Ca channels partly mediate the inhibitory effect of resveratrol on the neurogenic contractions of RPV. The smooth muscle Ca²⁺ channels and/or Ca²⁺ mobilizing through cells might be involved in the effects of resveratrol on the contractility of RPV. Our results are important for better understanding the impact of resveratrol on the portal circulation. Copyright © 2013 John Wiley & Sons, Ltd.     

Korean red ginseng (Panax ginseng C.A. Meyer) root fractions: differential effects on postprandial glycemia in healthy individuals

Ethnopharmacological relevance

Variations in ginsenoside profile may predict the postprandial glucose (PPG)-lowering efficacy of ginseng. Previously we reported differential PPG-lowering effects with two Korean red ginseng (KRG) root.

Fractions

body and rootlets, of variable ginsenoside profiles. Whether this effect is reproducible with a different KRG source is unclear. We therefore tested two root fractions from a KRG source with elevated ginsenoside levels to assess its effect on PPG.

Materials and Methods

After a 12-h overnight fast, 13 healthy individuals (6M:7F; age = 28 ± 10 y; BMI = 24.1 ± 3 kg/m2; FBG = 4.77 ± 0.04 mmol/L) randomly received either 3 g of KRG-body, rootlets or placebo, on three separate visits. Treatments were consumed 60 min prior to a standard test meal with capillary blood samples at −60, 0, 15, 30, 45, 60, 90 and 120 min.

Results

The KRGrootlets had > 6 fold total ginsensosides than the KRG-body but did not significantly affect PPG. Despite a reduced ginsenoside profile, KRG-body lowered PPG levels at 45, 60, 90 and 120 min during the test (p < 0.05), rendering an overall reduction of 27% in incremental area under the glucose curve compared to the control (p < 0.05).

Conclusions

Comparing the results with a previously studied batch of KRG suggests a potential therapeutic dose range for ginsenosides. This observation should be clinically verified with acute screening and ginsenoside composition analysis.     

Antioxidant activity of yellow dock (Rumex crispus L., Polygonaceae) fruit extract

The methanol extract of ripe Rumex crispus L. fruits was evaluated for its antioxidant potential by assays for ferric‐reducing antioxidant power (FRAP), DPPH‐free radical scavenging activity (DPPH) and the influence on lipid peroxidation in liposomes (LP). Considerable activity was observed in all test systems (FRAP: 9.9 mmol Fe²⁺/g; DPPH IC₅₀: 3.7 μg/mL; LP IC₅₀: 4.9 μg/mL), comparable to that of BHT (FRAP: 8.0 μg/mL; DPPH IC₅₀: 19.4 μg/mL; LP IC₅₀: 3.5 μg/mL), but lower than the activity of ascorbic acid, rutin and quercetin, used as positive control substances. The in vivo effects were evaluated in several hepatic antioxidant systems (activities of LPx, GSH‐Px, Px, CAT and XOD, as well as GSH content), after treatment with the studied yellow dock extract in different doses, or in combination with carbon tetrachloride (CCl₄). Pretreatment with the R. crispus extract inhibited CCl₄‐induced oxidative stress by decreasing LPx and increasing GSH content in a dose dependent manner, bringing the levels of antioxidant enzymes to near control values. Copyright © 2010 John Wiley & Sons, Ltd.